Paper Glossary



A4 (size)

A common ISO A-size of about 8 ¼ by 11 ¾ inches or 210 x 297mm. For all

sizes see International Paper and Board Sizes.


A fiber also known as manila hemp or manila fiber, prepared from the outer

sheath of the stems of manila.

ABCD Scheme

An initiative in the UK designed to classify the type and amount of

Recycled Fiber in a paper product. The scheme grades four types of waste

used in paper manufacturing, as follows:

A – Woodfree, approved own mill waste (waste that has not left the mill.

i.e. mill broke).

B – Woodfree unprinted waste (waste that has left the mill but not reached

the consumer, typically from the printer or converter).

C – Woodfree printed waste (post consumer waste, collected from homes,

offices etc).

D – Printed mechanical waste (post consumer waste, typically newspapers).

To be classified as recycled, the grade has to contain no less than 50% of

the total fiber from any combination of the above sources, with the

percentages given for each..


A material that resists adhesion. Abhesive coatings are applied to

surfaces to prevent sticking, etc.

Abrasion Resistance

The extent to which paper can withstand continuous scuffing or rubbing.

Abrasive Papers

Papers covered on one or both sides with abrasive powder, e.g. emery,

sandpaper etc.

Absolute Humidity

The actual weight of water vapor contained in a unit weight of air,

expressed in grams per cubic meter in metric system and pounds per cubic

feet in English system.

Absolute Viscosity

A characteristic of one-component liquids which have a constant ratio of

shear stress over shear rate (constant viscosity)

Absolute White

In theory a material that perfectly reflects all light energy at every

visible wavelength; in practice a solid white with known spectral data

that is used as the “reference white” for all measurements of absolute

reflectance. (When calibrating a spectrophotometer, often a white ceramic

plaque is measured and used as the absolute white reference).

Absorbable Organic Halogen (AOX)

A measure of the amount of chlorine that is chemically bound to the

soluble organic matter in the effluent.


The extent to which a paper will take up and hold a liquid.

Absorbent Core

The principal fluid-holding component of disposable hygiene products.

Absorbent cores usually contain a combination of absorbent cellulose

fibers (fluff pulps) and super-absorbent polymers composed of

polyacrylates. Advanced cores can contain very specialized absorbent

cellulose fibers, synthetic fibers and super-absorbent polymers as well as

fluff pulps.

Absorbent Paper

Papers having the specific characteristic of absorbing liquids such as

water and ink. These papers are soft, loosely felted, un-sized and bulky

e.g. blotting paper.

Absorbent Paper

Papers having the specific characteristic of absorbing liquids such as

water and ink. These papers are soft, loosely felted, unsized and bulky

e.g. blotting paper.

Accelerated Aging

Exposing paper at elevated temperature usually at 110C in an oven or on a

hot plate. The purpose of accelerated aging is to simulate the effect of

aging in the laboratory.


Accepted portion of pulp after cleaning and or screening operation.

Accordion Fold

A term for two or more parallel folds that result in the sheet opening

like a fan. Accordion folds are used on products such as brochures and


Acetate Pulp

A highly purified (high alpha cellulose) pulp made especially to be

dissolved in acetic acid, acetic anhydride and sulfuric acid to make

acetate rayon and acetate fiber.


Material that is white, gray and black and have no color or hue.

Acid Detergent Fiber (ADF)

Organic matter that is not solubilized after 1 hour of refluxing in an

acid detergent of cetyltrimethylammonium bromide in 1N (Normal) sulfuric

acid. ADF includes cellulose and lignin.

Acid Free Paper

A type of paper, which does not contain any acidic substance that may

affect acid sensitive material. Acid free paper is anti rust and is used

for metal wrapping.

Acid Hydrolysis

The treatment of cellulosic, starch, or hemicellulosic materials using

acid solutions (usually mineral acids) to break down the polysaccharides

to simple sugars..

Acid Migration

The transfer of acid from an acidic material to a less acidic or

neutral-pH material. Occurs when neutral materials are exposed to

atmospheric pollutants or when two paper materials come in contact. Acid

can also migrate from adhesives, boards, endpapers, protective tissues,

paper covers, acidic art supplies, and memorabilia.

Acid Proof Paper

A paper that is not affected by acid physically or chemically. This paper

is used with substance containing acid.

Acid Sizing

Internal sizing carried out in acidic pH range (0-7). Rosin and alum

sizing is acid sizing.

Activated Carbon

A highly absorbent powdered or granular carbon used for purification by


Activated Sludge

The biomass produced by rapid oxygenation of effluent.

Active Alkali (AA)

Caustic (NaOH) and Sodium sulfide (Na2S) expressed as Na2O in alkaline

pulping liquor.


Clay, fillers, dyes, sizing and other chemicals added to pulp to give the

paper greater smoothness, color, fibered appearance or other desirable


Adhesive Paper

Base paper for coating with an adhesive, the type depending upon end use.

Aerated Lagoon

A biological wastewater treatment method in which air (oxygen) fed into an

aeration basin reduces the effluent load.

Against the Grain

Cutting, folding or feeding paper at right angles to the grain or machine

direction of the paper.


Irreversible alteration, generally deterioration, of the properties of

paper in course of time. Aging also causes reduction in brightness and

yellowing effect.


Equipment used to keep content of a tank or chest in motion and well


Air Brush Coater

A coater, which uses the pressurized air to atomize the coating mixture

and spray it on the paper.

Air Dry (AD)

Refers to the weight of dry pulp/paper in equilibrium with the atmosphere.

Though the amount of moisture in dry pulp/paper will depend on the

atmospheric condition of humidity and temperature but as a convention 10%

moisture is assumed in air dry pulp/paper.

Air Drying

Using hot air to dry pulp or paper sheets.

Air Filter Paper

A type of paper used for filtration of air to remove suspended particles.

(car air filter, vacuum bag etc.)

Air Knife Coater

A device that applies an excess coating to the paper and then removes the

surplus by impinging a flat jet of air upon the fluid coating, leaving a

smooth, metered film on the paper.

Air Mail Paper

It is lightweight, high opacity, good quality writing/printing type paper

used for letters, flyers and other printed matter to be transported by


Air Permeability

Commonly referred to as “porosity.” The ease with which pressurized air

can flow through a paper’s thickness. Typically measure by the Gurley or

the Sheffield porosity tests, which measure the volumetric flow of air

through the paper thickness.

Air Pollution

The contamination of air around the plant due to the emission of gases,

vapors and particulate material in the atmosphere.

Album Paper

Paper used in photographic albums. It has a soft surface which will not

wrinkle or cockle when photographs are pasted or glued on it, and when wet

with such adhesive, it will not ‘bleed’.

Albumin Paper

A coated paper used in photography; the coating is made of albumen (egg

whites) and ammonium chloride.


Micro organic plant life that forms in paper mill water supplies.

Alkali Lignin

Lignin obtained by acidification of an alkaline extract of wood.

Alkali Proof Paper

A paper, either white or colored, which does not discolor when in contact

with alkaline materials, such as soap. Careful selection of fibers and

coloring matters is necessary, but no particular strength requirements

need be met. Many book papers are sufficiently alkali-proof and glassine

and waxed papers are also satisfactory.

Alkali Resistance

Freedom of paper from a tendency to become stained or discolored or to

undergo a color change when brought in contact with alkaline products such

as soap and adhesives.

Alkaline Extraction

Alkaline extraction, i.e. E stage, is used in lignin removal before or

between bleaching stages; the stage is often enhanced with an oxidizing

agent, oxygen (Eo stage), hydrogen peroxide (Ep stage) or both (Eop


Alkaline Paper

Paper having pH values greater than 7 and made by using an alkaline sizing


Alkaline Papermaking

Paper manufactured under alkaline conditions, using additives, basic

fillers like calcium carbonate and neutral size. The anti-aging properties

in alkaline paper make it a logical choice for documents where permanence

is essential.

Alkaline Pulping

Pulping by alkaline solutions of sodium hydroxide, with or without sodium

sulfide. Without sodium sulfide it is called soda process and with sodium

sulfide it is known as Kraft or sulfate process.

Alkenyl Succinic Anhydride (ASA)

ASA is a sizing agent designed to increase resistance to water penetration

in the case of paper formed under neutral or alkaline conditions. ASA is

especially used in cases where full cure is desired before the size press

and where it is important to maintain a high frictional coefficient in the

paper product. ASA can improve paper machine runnability and preserve

paper’s dimensional stability by limiting penetration of size-press

solution into the sheet.

Alpha Cellulose

The portion of the pulp or other cellulosic material that will not

dissolve in 17.5% NaOH (Sodium Hydroxide) solution at 20oC.

Alpha Pulp

A specially processed, high alpha cellulose content, chemical pulp. It is

also called dissolving pulp.

Alternative Fibers

Common name for non-wood or tree free fibers.


The paper maker alum is hydrated Aluminum Sulfate {Al2(SO4)3}. Used to

adjust the pH of the mill water or as a sizing chemical in combination

with rosin size.

Aluminum Foil Lamination

The combination of thin Aluminum foil with a paper backing used as a

positive moisture barrier. Normal combination is kraft backing with

Aluminum foil laminated to the kraft by means of asphalt, adhesive, or

polyethylene. The Aluminum foil can also be coated with polyethylene.

Ammunition Paper

The type of papers used in the manufacture of ammunition such as cartridge

paper, which forms the tube section of shotgun shell and basewad paper,

which is used in the base of the shell.

Anaerobic Reactor System

An effluent treatment system that uses microbes in the absence of oxygen

to break down effluent constituents into methane, carbon dioxide and

hydrogen sulfide.

Announcement Cards Paper

Cards of paper with matching envelopes generally used for social

stationery, announcements, weddings, greetings, etc.

Annual Vegetable Fiber or Agricultural Residue Fiber

A source of fiber for pulp and papermaking, including, for example, wheat

or rice straw or other fibrous by-products of agriculture.

Anthra Quinone (AQ)

A quinoid compound added to white liquor (alkaline cooking liquor) to

improve pulp yield and to increase the rate of delignification.

Anti Rust Paper

Paper containing added substances which give it the property of protecting

the surfaces of ferrous metals against rusting.

Anti-foam or Defoamer

Chemical additives used at wet end to reduce or eliminate tendencies of

the machine white water to foam.

Antique Finish

A term describing the surface, usually on book and cover papers, that have

a natural rough finish.

Antique Paper

Printing paper having good bulk and opacity with rough or matt surface.

Anti-Tarnish Paper

A term originally applied to tissues used for wrapping silverware, but now

used for all papers so prepared that they will not rust or discolor razor

blades, needles, silverware, etc. Various fibers are used and weights of

paper made; the chief requirements are freedom from acidity and reducible

sulfur compounds. Copper salts or other inhibitors are sometimes used for

silver tissues.

Apparent Density

Weight (mass) per unit volume of a sheet of paper obtained by dividing the

basis weight by the Caliper (thickness).

Apparent Viscosity

A characteristic of multi-component liquids that have a variable ratio of

shear stress over shear rate (variable viscosity depending on conditions).


Means of applying the aqueous coating, sizing or coloring to the paper


Approach Flow System

The stock flow system from Fan pump to headbox slice.

Aqueous Coating

A water-based coating applied after printing, either while the paper is

still on press (“in line”), or after it’s off press. An aqueous coating

usually gives a gloss, dull, or matte finish and helps prevent the

underlying ink from rubbing off. Unlike a UV coating or a varnish, an

aqueous coating will accept ink-jet printing, making it a natural choice

for jobs that require printing addresses for mass mailings.

Archival Paper

A paper that is made to last for long time and used for long lasting


Art Paper

High quality and rather heavy two-side coated printing paper with smooth

surface. The reproduction of fine screen single- and multicolor pictures

(“art on paper”) requires a paper that has an even, well closed surface

and a uniform ink absorption.

Artificial Parchment

Wood free paper that is produced by fine and extended grinding of certain

chemical pulps and/or the admixture of special additives. As a result of

the “smeary” grinding, the fiber structure closes homogeneously. It is

used e.g. for wrapping meat and sausages or as corrugating medium for

biscuit packaging

Asbestos Paper

A fire retardant and heat insulating paper made chiefly from asbestos

fiber on a cylinder machine. Generally not over 0.06 of an inch thick.

Aseptic Packaging

Extends the shelf life of non-refrigerated beverages and foods. Laminates

and extruded coatings applied by the customer ensure an appropriate liquid

barrier. Aseptic grade board is clay-coated on one side and is suitable

for gravure, offset, and flexographic printing.

Ash Content

The residue left after complete combustion of paper at high temperature.

It is generally expressed as percent of original test sample and

represents filler content in the paper.

Asphalt Laminated Paper

Two sheets of natural kraft paper laminated in a single ply by means of

asphalt. This is used as a moisture barrier; also to resist action of weak

acids and alkalis .

Automatic Packaging System

Term applicable to any one of several available systems for open mouth and

valve bag packaging where bags are automatically applied to filler spout,

filled, weighed, closed (if open mouth), palletized, and shrink wrapped.


The light blue color used in the nomenclature of “laid” and “wove” papers.

Azurelaid Paper

A laid paper usually bluish green in colour having a good writing surface.


Back Liner

The back side layer in a multi-ply paperboard. Normally back liner is made

out of inferior grade pulp compared to top liner.

Back Liner

The back side layer in a multi-ply paperboard. Normally back liner is made

out of inferior grade pulp compared to top liner.

Back Water

See White Water.


The back of a bound book; also called the spine.

Backing Roll

Rubber covered roll against which the metering device such as rod or blade

can press.

Backing up

Printing the reverse or back side of a sheet that has already been printed

on one side.


A device which obstructs the flow of fluid, whether to aid mixing or

restrict the flow rate.

Bag House

An air pollution control device that captures particulate in filter bags.

Bag Paper

Any paper made to be used in the manufacturing of bags.


Sugarcane residue left after extracting the juice.

Baggy Roll

Mill roll defect usually associated with a variation in caliper and/or

basis weight across the width. Rolls are normally checked for baggy areas

by striking with a baton and listening for variations in audible pitch.


A large rectangular shaped compressed package of waste paper, rag, pulp

etc. Bale dimensions and weight varies widely depending on the baling

material and handling capabilities.


Compressing and wrapping a material with wire, twine, string to form a

unit which is more readily handled, stored and transported.


A plant of grass family grown in Asian countries and used for papermaking


Banknote or Currency Paper

Used for printing currency. De-facto highest grade of paper. Very high

folding endurance, permanency, tensile strength, suitable for 4-colour

printing, with watermark and other falsification safeguards such as

embedded metal strip. Often contains cotton fibers.


The outer protective layer of a tree outside the cambium comprising the

inner bark and the outer bark. The inner bark is a layer of living bark

that separates the outer bark from the cambium and in a living tree is

generally soft and moist. The outer bark is a layer of dead bark that

forms the exterior surface of the tree stem. The outer bark is frequently

dry and corky

Barker or Debarker

Equipment used to remove bark from wood.

Barking or de-barking

Removing bark from wood.

Barograph Paper

Red thin paper coated on one side with a white wax, so that the needle of

the barograph make a red line on a white ground, sold in rolls and coils

and to suit the type of barograph.

Barograph Paper

Red thin paper coated on one side with a white wax, so that the needle of

the barograph leaves a red line on a white ground, sold in rolls and coils

and to suit the type of barograph.

Baryta Paper

A paper coated with barium sulfate to give a smooth, low-gloss surface;

used chiefly as a base for photographic emulsions.

Base Paper

Refers to paper that will be subsequently be treated, coated or laminated

in other ways.

Basic Dye

Dye that have a positive charge due to amine groups and have a strong

affinity for the surfaces of high-yield fibers. Basic dyes are economical,

have high color strength but very poor light-fastness.

Basis Weight

In English system of units, basis weight is the weight in pounds of a ream

(500 sheets) of paper cut to a basic size. (Basic size differs from

category to category of the paper. Basic size for Bond and Ledger is

20″x26″, book, offset and text paper have basic size of 25″x38″). In

metric system of units, basis weight is the weight in grams of a single

sheet of area one square meter. Basis weight is also called as substance

and grammage in metric system of units.

Bast Fibers

Fibers derived from the bark of some annual plants such as flax, gampi,

hemp, jute, kozo and mitsumata etc. Main characteristic of these fibers is

long length.

Bastard Size

The non-standard sheet size of a given grade.

Batch Cooking

A chemical pulping process in which a discrete quantity of fibrous raw

material is individually process.


Equipment used for beating, refining and mixing pulps.

Beater Dye

Dye added to the beater to color the pulp.

Beater Loading

Addition of a filler to the pulp in the beater.

Beating or Refining

The mechanical treatment of the fibers in water to increase surface area,

flexibility and promote bonding when dried.

Beedi Wrap Paper

Used for wrapping beedi (east Indian style cigarette) and decorative

purposes in different colours.

Belt Washer

Washer, which uses rotating wire for dewatering and washing of pulp.

Bending Resistance/Flexural Stiffness

Corrugated board’s ability to resist bending, along with its edge crush

resistance, relates to the top-to-bottom compression strength and general

performance of corrugated containers.

Bible Paper

Thin white opaque heavily loaded, used for printing bibles. Not suitable

for pen and ink, because of its absorbency.


Chemicals which facilitate fiber bonding.

Binder (Coating)

A natural or synthetic compound used to adhere coating to the paper


Biochemical Oxygen Demand (BOD)

When effluent containing biodegradable organic matter is released into a

receiving water, the biodegradation of the organic matter consumes

dissolved oxygen from the water. The BOD of an effluent is an estimate of

the amount of oxygen that will be consumed in 5 days following its release

into a receiving water; assuming a temperature of 20°C.


A biological control chemical such as fungicide or a bactericide used in



Capable of destruction by biological action.

Biological Waste Water Treatment

A method of cleaning up waste water using living micro-organisms such as



Any plant-derived organic matter. Biomass available for energy on a

sustainable basis includes herbaceous and woody energy crops, agricultural

food and feed crops, agricultural crop wastes and residues, wood wastes

and residues, aquatic plants, and other waste materials including some

municipal wastes. Biomass is a very heterogeneous and chemically complex

renewable resource..

Biomass Boiler or Hogged Fuel Boiler

Biomass boilers burn bark, saw mill dust, primary clarifier sediment and

other solid waste, and other wood-related scrap not usable in product

production. Also called “hogged fuel” boilers, biomass boilers make steam

and heat for mill use.


Sludge formed (in the aeration basin) during biological waste water

treatment or other biological treatment process.


Bitoko/Bitokoshi is a grade of printing and writing paper unique to Japan.

It is a very lightly coated paper, occupying a niche market between LWC

and coated woodfree papers. The furnish includes both chemical and

mechanical pulp in variable proportions, thus the Japan Paper Association

(JPA) recognizes both woodfree bitokoshi and mechanical bitokoshi

depending on the proportion of mechanical pulp in the furnish.

Black Liquor

The liquor that exits the digester with the cooked chips at the end of the

Kraft cook is called “black” liquor.


Defect associated with calendered paper occurring as unintended local

areas of apparently darker or grayer color due, for example, to the paper

being too damp when passed through the calender.

Blade Coater

A device that first applies a surplus coating to paper and then remove

extra color after evenly leveling by means of a flexible steel blade.

Blade Wrapping Paper

Translucent paper used for individual wrapping of razor blades.


A name applied to thick cardboards, coated or uncoated, pasted or

unpasted, and made in standard thicknesses with either white or colored

liners. They should have maximum smoothness of surface and stiffness. They

range from 0.012 to 0.078 of an inch with corresponding ream weights of

120 to 775 pounds (22 x 28-500). Their use is for calendar backs, signs,

and window displays.

Blank or Black Box

A flat sheet of corrugated or solid fiberboard that has been cut, slotted

and scored so that, when folded along the score lines and joined, it will

take the form of a box.

Bleach Plant

Section of a pulp mill where pulp is bleached


A chemical process used to whiten and purify the pulp. Bleaching also adds

to the sheet’s strength and durability.

Bleaching Sequences

Series of subsequent bleaching stages, typically described by abbreviation

such as CEHH (Chlorination, Extraction Hypochlorite, Hypochlorite .


The feathered edge of inks caused by absorption into un-sized paper.

Bleed (corrugation)

The penetration of laminating agents, such as asphalt, through the kraft

plies making up the combination.

Bleed Through

When printing on one side of a sheet of paper shows through to the other


Blending or Mixing

Blending of different pulps in a chest to achieve quality of the final


Blind Drilled Roll

A matrix of small holes drilled into the soft press roll which aid the

water removal capability of that roll.

Blind Embossing

A printing technique in which a bas-relief design is pushed forward

without foil or ink.


Defect on a paper surface often shaped like a human blister. It is due to

de-lamination of a limited portion of paper without breaking either


Blister Resistance

Resistance of paper to developing blister during printing and print


Bloodproof Paper or Butcher Paper

A high strength paper having maximum resistance to animal blood. It is

used for wrapping fresh meat. It is normally sized with wax emulsion or

other anti-absorption chemicals.

Blotting Paper

An un-sized paper used generally to absorb excess ink from freshly written

manuscripts, letters and signatures.


It is the discharging of the pressure and contents of the digester in to

blow tank.

Blow Heat Recovery System

The system used to recover heat from the flash steam generated while

digester is blown in to blow tank.

Blow Tank

The tank in which cooked chips and spent liquor is blown from digester at

the end of the cooking cycle.

Blueprint Paper

Base paper for blue printing. See Diazo Base Paper.


Thick and stiff paper, often consisting of several plies, widely used for

packaging or box making purposes. Its grammage normally is higher than 150

g/m2 or thickness is more than 9 point (thousandth of an inch).

Bogus Paper

Bogus refer to a product that is made from recycled fiber or an inferior

pulp to imitate higher quality grades. There are bogus back liner, bogus

bristol, bogus kraft, bogus wrapping etc. Gray bogus is used for packaging

material, void fill, wipes, bedding, and a variety of other industrial and

agricultural purposes. It is biodegradable.

Bond Paper

The name “bond” was originally given to a paper, which was used for

printing bonds and stock certificates. It is now used in referring to

paper used for letterheads and many printing purposes. Important

characteristics are finish, strength, freedom from fuzz, and rigidity.

Bonding Strength

The internal strength of a paper; the ability of the fibers within a paper

to hold to one another. Bonding strength measures the ability of the paper

to hold together on the printing press or other converting processing

machines. Good bonding strength prevents fibers from coming loose

(“picking”). Bonding strength of fiber is improved by beating/refining

and/or adding bonding agent.

Bone Dry

Moisture free or zero moisture.

Book Paper

A general term used to define a class or group of papers having in common

A paperboard used in the manufacture of light non-corrugated container.


A rigid container having closed faces and completely enclosing its



A class of board frequently lined on one or both sides, with good folding

properties and used for making box and cartons.

Braille Printing Paper

Used for embossing dot patterns used by blinds in touch reading. It is

bulky. The sheet must be smooth so the dots will be pronounced. The

caliper should be uniform, so all dots are of same height.

Bread Wrapping Paper

Used for wrapping sliced bread. It is thin, waxed paper normally made

opaque for printing by loading with titanium dioxide.

Breaking Length

The length beyond which a strip of paper of uniform width would break

under its own weight if suspended from one end. Usually expressed in



Rupture of paper on the paper machine during paper making. It the paper on

couch roll, it is termed couch break. If the paper breaks in paper

section, it is termed as press break. If the paper breaks in dryer

section, it is dryer breaks and so on.

Breast Roll

A medium size metal or plastic/fiberglass/granite covered roll located at

the headbox side of the paper machine to support the wire.


The reflectance or brilliance of the paper when measured under a specially

calibrated blue light. Not necessarily related to color or whiteness.

Brightness is expressed in %.

CIE Brightness: An internationally-recognized standard of paper

brightness developed in Europe by the Centre Internationale d’Eclairage


Bristol Board

A fine quality cardboard made by pasting several sheets together, the

middle sheets usually of inferior grade.


Property of paper causing it to break while bending.


Paper that is unusable because of damage or non-conformity to the

specifications. It is put back in to the pulping system.

Broke Pit

A pit below the machine in to which broke is disposed from the machine


Broke Pulper

A broke pulper is used to break down the broke into a stock that can be

pumped and treated. This term can cover a wide range of machines and is

often used to refer to both stand alone broke pulpers and under the

machine (or UTM) pulpers which receive paper directly from the machine

including any trim. A stand alone broke pulper is used to process finished

reels that have been rejected or for broke that for any reason has been

baled or collected away from the UTM pulpers

Brown Pulp

A mechanical pulp made from wood, which is steamed before grinding. The

color-bearing, non-cellulosic components of the wood remain with the pulp.

The pulp is generally used for wrapping and bag paper.

Brown Stock

The unbleached chemical pulp.

Brush Coating

A Coating method in which the freshly applied coating color is regulated

and smoothed by means of brushes, some stationary and some oscillating,

before drying.


The neutralizing of acids in paper by adding an alkaline substance

(usually calcium carbonate or magnesium carbonate) into the paper pulp.

The buffer acts as a protection from the acid in the paper or from

pollution in the environment.


Reverse of density, expressed as cubic centimeter per gram.


The loss of color during drying.

Burnt Paper

Paper, which has been discolored and is brittle, but otherwise intact.

Burnt Paper

Paper, which has been discolored and is brittle, but otherwise intact.


An irregular separation or rupture through the paper or package.

Air Shear burst: Burst caused by air trapped in the winding roll

producing rupture of the web along the machine direction.

Caliper shear burst. Cross Machine tension burst that generally

occurs between an area or relatively high and low caliper extending for

some distance in the machine direction; due to non uniform nip velocities

between hard and soft sections of the roll.

Core burst: Inter-layer slippage just above the core, often over the

key way, which terminates an Air Shear Burst. Core bursts are most often

seen on core-supported unwinds and winders.

Burst Factor

The ratio of the bursting strength (expressed in g/cm2 ) and the substance

of paper/paperboard (expressed in g/m2) determined by standard methods of


Burst Index

The ratio of the bursting strength (expressed in kilo Pascal ) and the

substance of paper/paperboard (expressed in g/m2) determined by standard

methods of test.

Burst Ratio

The ratio of the bursting strength (expressed in lb/inch2 ) and the

substance of paper/paperboard (expressed in lb/ream) determined by

standard methods of test.

Bursting Strength

The resistance of paper to rapture as measured by the hydrostatic pressure

required to burst it when a uniformly distributed and increasing pressure

is applied to one of its side.

Business Form Paper

Used for business forms and data processing such as computer printouts.

Butter Wrapping Paper

Paper, which is used for wrapping butter, margarine etc.



Coated on one side of the paper.


Coated on both sides of the paper.

Cable paper

A strong paper suitable for cutting into narrow strips and winding on wire

as insulation. High tensile strength is essential.

Calcium Carbonate

CaCO3, a naturally occurring substance found in a variety of sources,

including chalk, limestone, marble, oyster shells, and scale from boiled

hard water. Used as a filler in the alkaline paper manufacturing process,

calcium carbonate improves several important paper characteristics, like

smoothness, brightness, opacity, and affinity for ink; it also reduces

paper acidity. It is a key ingredient in today’s paper coatings.


A stack of highly polished metal cylinders at the end of a paper machines

that smoothes and shines the paper surface as sheets pass through.

Calender Blackening

Coverage of calendered paper web with glazed translucent spots due to

excessive calender roll heat, calender pressure, poor and/or excessive and

uneven moisture.

Calender Cut

Weak lines or fractures in paper that break easily under tension, caused

by wrinkles going through the calender stack of the paper machine.

Calender Spots

Paper defect usually indicated as a transparent spot in the sheet; caused

by foreign material adhering to a calender roll and being impressed into

the sheet with each revolution.


The thickness of paper usually expressed in thousandths of an inch in

English system of units and in millimeter in Metric system of units.


Larger diameter in the centre of a papermaking rolls (press & calender

etc), compared to the ends, to compensates the deflection of roll due to

its own weight.

Canadian Standard Freeness (CSF)

It is a measure of pulp freeness. The unit of measurement is ml CSF.

Candy Twisting Tissue

A light-weight paper, generally waxed for wrapping candy kisses, taffy,


Capacity Utilization Rate

The production rate a plant or machine is operating with respect to design

capacity. Also in some cases it indicates the efficiency (%) at which a

plant or machine is operating.


Organic compounds made up of carbon, hydrogen, and oxygen and having

approximately the formula (CH2O) n; includes cellulosics, starches, and


Carbon Offsets

The financial instrument, utilized by individuals or companies,

representing a reduction in greenhouse gas emissions.

Carbon paper

A low basis weight paper (8 to 15 g/m2) with very low air permeability,

free of pin holes and with a waxy coating that is used to produce carbon

copies on typewriters or other office equipment.

Carbonless Paper

A paper that uses a chemical reaction between two different contacting

coatings to transfer image when pressure is applied.


A thin, stiff paperboard made of pressed paper pulp or sheets of paper

pasted together. Used for playing cards, greeting cards, etc.


A thin, stiff paperboard made of pressed p


A folding box made from boxboard, used for consumer quantities of product.

A carton is not recognized as a shipping container

Carton board

A rigid wood fibre based packaging material. Carton-board is normally of

at least 180 g/m2 substance and 250 microns thickness.

Cartridge paper

Tough, slightly rough surfaced paper used for a variety of purposes such

as envelopes; the name comes from the original use for the paper which

formed the tube section of a shotgun shell.

Cast Coated Paper

A coated paper with high gloss and absorptivity in which the coating has

been allowed to harden or set while in contact with a mirror like polished

chrome surface.

Cast Coater

A device that applies a wet coating color to a paper web before it

contacts a heated drum having a highly polished surface, which cast the

coating in to an image of the smooth, mirror-like drum surface.

Catalog Paper

A light weight, highly opaque and good strength paper typically used for

mail order catalog and telephone directory..


It is the process in which Green Liquor is converted in to White Liquor.

Technically speaking it is the process of converting sodium carbonate in

to sodium hydroxide.


It is a high molecular weight, stereoregular, and linear polymer of

repeating beta-D-glucopyranose units. Simply speaking it is the chief

structural element and major constituents of the cell wall of trees and


Cellulose Fiber

An elongated, tapering, thick walled cellular unit, which is the main

structural component of woody plants. Fibers in the plants are cemented

together by lignin. In British English Fiber is spelled as Fibre. Thermal

conductivity of cellilose fiber varies from 0.034 to 0.05W/m K, making it

a good insulator.


Improper drying of ink. Ink vehicle has been absorbed too rapidly into the

paper leaving a dry, weak pigment layer which dusts easily.

Chart Paper

A paper with the characteristics of bond or ledger papers. It must have

good printing and erasing properties and low expansion and contraction

with changing humidities. Used for making charts and graphs.

Check or Cheque Paper (MICR)

A strong, durable paper made for the printing of bank checks or cheques.

By careful formulations the paper is designed to react against a wide

range of ink eradicators. It gives a characteristic coloured stain of

“flare up” on contact with acid, alkali, bleach and organic solvents like

acetone, benzene, ethanol.

Chelating Agent

An organic compound that forms more than one coordinate bond with metals

in solution; organic compound participating in chelation; e.g. EDTA and



A chemical complexing (forming or joining together) of metallic cations

(such as iron) with certain organic compounds, such as EDTA (ethylene

diamine tetracetic acid); a reaction between a metallic ion and an organic

compound that removes the metallic ion from solution.

Chemical Ghosting

A light duplication of a printed image on the other side of the same

sheet, created by chemical reaction by the ink during the drying stages;

also referred to as “gas ghosting.”.

Chemical Oxygen Demand (COD)

The amount of oxygen consumed in complete chemical oxidation of matter

present in waste water; indicates the content of slowly degradable organic

matter present. COD is easier to measure compared to BOD (Biological

Oxygen Demand).

Chemical Pulp

Pulp obtained from the chemical cooking or digestion of wood or other

plant material.

Chemical Recovery

It is the process in which cooking chemicals are recovered.

Chemo-Thermo-Mechanical Pulp (CTMP)

Mechanical pulp produced by treating wood chips with chemicals (usually

sodium sulfite) and steam before mechanical defibration.


Vessel equipped with an agitating device for storing, collecting, mixing,

blending and/or chemical treatment of pulp suspension. Chest can be

horizontal and or vertical. Tower are special type of chest generally used

in bleached plant to provide retention time and to provide down/upward

flow out of pulp.

Chief Sustainability Officer

An executive put in charge of a corporation’s environmental programs.

China Clay

Natural mineral, consisting essentially of hydrated silicate of alumina,

used as a filler or as a component in a coating color. (Also see clay)


Wood chips produced by a chipper; used to produce pulp, fiberboard and

particle board, and also as fuel.


A paperboard, thicker than cardboard, used for backing sheets on padded

writing paper, partitions within boxes, shoeboxes, etc.


The machine that converts wood logs in to chips.

Chlorine Number

A test method to determine the bleach requirement of a pulp. It indicates

the number of grams of chlorine consumed by 100 g of pulp under specified



A term used to describe both papers and boards used for subsequent brush

coating. The various qualities are determined both by the actual grade of

base material used and the quality of the coating, which may be gummed.

Coating may be applied to one or both sides, depending on end use.

Cigarette Paper

This light weight, unsized paper (grammage 18 to 24g/m2), converted to

improve glowing. It normally has approx. 30% calcium carbonate as filler

to control the burning rate and match it with tobacco burning rate. Very

long fiber such as jute, cotton etc is used to achieve high strength and



Basin where sludge is removed from treated effluent by settling.


A natural substance used as both a filler and coating ingredient to

improve a paper’s smoothness, brightness, opacity and/ or affinity for


Clay Coated Boxboard

A grade of paperboard that has been clay coated on one or both sides to

obtain whiteness and smoothness. It is characterized by brightness,

resistance to fading, and excellence of printing surface. Colored coatings

may also be used and the body stock for coating may be any variety of



A conical or partly cylindrical device with no moving parts, designed to

remove grit from thin-stock furnish by the centrifugal action of rotating


Closed System

Papermaking system wherein white water is mainly re-circulated and not

discharged as effluent.


Thick element composed of several entangled fibers. Its presence is

harmful to the production process and needs to be eliminated.

Coarse Paper (also Industrial Paper)

Various grades of papers used for industrial application (abrasive, filter

etc.) rather than cultural purposes (writing, printing etc.)

Coat Weight

The amount of coating applied to base paper, expressed as pounds of

air-dried coating on the surface of a 25X38 in ream or grams per meter


Coated Paper

Term that applies to paper which has a special coating applied to its

surface. Material such as clay, casein, bentonite, talc, applied by means

of roller or brush applicators; or plastics applied by means of roll or

extrusion coaters.

Coated White Top Liner

White liner that is coated to produce superior printability.


Process by which paper or board is coated with an agent to improve its

brightness and/or printing properties.

Coating Color

Mixture used to coat paper and board: contains pigment, binder, special

additives and water.

Coating Color Kitchen

Section of Coating Plant where coating colour is prepared and mixed

Cobb Test

Measures paper’s water absorption rate and is expressed as the amount of

water pick-up per unit surface area of paper by Tappi method T441. The

test duration must be specified to properly know the absorption rate.

United Nations (UN) and Code of Federal Regulations require the 30-minute

pick-up must be 155 grams per square meter or less for containerboard used

in hazardous material transport.

Cockle Finish

Produced by air drying paper with controlled tension. This uneven surface

is available in bond papers.

Cockle Finish Paper

A finish that simulates characteristics of hand made paper with a wavy,

rippled, puckered finish. The effect is obtained by air drying the paper

under minimum tension.


When the surface of the paper has wave like appearance.

Coffee Filter Paper

Used for coffee filtering. Paper should have no impurities or fillers. It

is a wet strength paper and able to withstand boiling water. Synthetic

resins are used for to provide wet strength.


It is the process to generate electricity from high pressure steam and

using low and/or medium pressure steam in the mill process.

Cold Blow

Pressure ejection of cooked pulp from batch or continuous digesters after

the pulp has been cooled to below 100oC. The cooling step reduces damage

to the fibers.

Colored Kraft

Natural or bleached kraft paper to which a dye or pigment has been added.

Colored Pigments

These are water insoluble colored materials. They belong in the category

of fillers and loading material but are colored and used in small

quantity. Pigments have no affinity to fiber and must be used in

conjunction with alum or a cationic retention aid in order to retain them.

Color-fast papers

Colored papers that will not run when wet or fade under bright light.

Combined Deinking

Deinking process combining flotation and washing.

Commodity Paper

A classification for low-quality bond and offset papers.

Compression Strength (CD or MD)

Can be referred to as ring crush or “STFI (stiffy)”. The amount of force

needed to crush paper resting on its edge. Compression testers hold and

support the paper specimen so as to emulate its position and orientation

in the walls of a corrugated container. Due to the corrugated board making

process, paper must support compressive loads orthogonal to their grain (a

CD orientation). The test is unidirectional so the paper orientation

during testing must be known.

Condenser Tissue

A very thin paper of uniform thickness, good formation, and especially

free from conducting particles. Used as a dielectric between the foils of


Coniferous Trees

Cone bearing and evergreen trees. Also known as soft wood trees. e.g.

pine, spruce etc.


The percentage of bone dry solids by weight in pulp or stock.

Consistency Regulator

A device or instrument used to regulate the consistency of the pulp

on-line. Regulator works only in reducing the consistency i.e. add water,

but can’t remove water or thicken.

Construction Paper

Sheathing paper, roofing, floor covering, automotive, sound proofing,

industrial, pipe covering, refrigerator, and similar felts.


The paperboard components (linerboard, corrugating material and chipboard)

used to manufacture corrugated and solid fiberboard. The raw materials

used to make containerboard may be virgin cellulose fiber, recycled fiber

or a combination of both.

Continuous Pulping

Production of pulp in continuous digester as compared to a batch digester.


Unsuitable material found in wastepaper which must be removed from the

pulp before making it into paper, e.g. paperclips, string, plastics.


The degree of difference between light and dark areas in an image. Extreme

lights and darks give an image high contrast. An image with a narrow tonal

range has lower contrast.


The operation of treating, modifying, or otherwise manipulating the

finished paper and paperboard so that it can be made into end-user



Reacting fibrous raw material with chemical under pressure and temperature

to soften and or remove lignin to separate fibers.

Cooking Liquor

Liquor made up of selected chemicals and used for cooking pulp. e.g.

cooking liquor in kraft pulping mainly consist of NaOH and Na2S.

Cooling Cylinders or Cooling Drums

Water cooled cylindrical metal vessel over which dry paper web after

dryers is passed to cool the paper before calendering..

Copier Paper or Laser Paper

Lightweight grades of good quality and dimensionally stable papers used

for copying correspondence and documents. For detailed characteristics of

copier/Laser paper, please visit Paper Needs of Xerographic Machines (A

Summary) by Chuck Green

Copper Number

It is the measure of degree of fiber degradation. It is weight of copper

in grams reduced to cuprous state by 100 grams of pulp.


Pulpwood volume measurement indicating a pile measuring 4 ft x 4 ft x 8

ft, equaling 128 ft³ (3.62 in³). Also see cunit


Fibrous tube used to wound paper for shipment.

Core Plug

Metal, wood, particleboard, or other material plugs which are driven into

the ends of the paper core of finished roll to prevent crushing of the


Corona Treatment

An electrostatic treatment that reduces the surface tension of a substrate

(e.g., a polycoated substrate) to ensure adhesion of ink and glue.

The Corona treatment involves high voltage, high frequency electricity

discharged from an electrode when it pours through the polycoated board

increases the surface energy of the board to better receive inks or glue.

Correspondence Papers

Writing papers in attractive finishes, weights or colors.

Corrugated Board

Usually a nine-point board after if has passed through a corrugating

machine. When this corrugated board is pasted to another flat sheet of

board, it becomes single-faced corrugated board; if pasted on both sides,

it becomes double-faced corrugated board or corrugated (shipping)


Corrugated Container

Containers made with corrugating medium and linerboard.

Corrugated Medium or Fluting Media or Media

The wavy center of the wall of a corrugated container, which cushions the

product from shock during shipment (see flute). Media can contain up to

100% post-consumer recycled fiber content without reducing its ability to

protect the product.


Machine that presses medium into flutes, applies glue to the medium and

affixes sheets of linerboard to form corrugated board .

Cotton Fiber

Cotton is a natural fiber and is one of the strongest and most durable

fibers known to man. Papers manufactured of cotton fiber will last longer

and hold up better under repeated handling and variant environmental

conditions than paper made from wood pulp. Generally, given reasonable

care, one can expect one year of usable life for every 1% of cotton

contained in the sheet. Typically cotton fiber papers are made of either

all cotton fiber (100% cotton) or a blend of cotton and wood pulp.

Cotton Linter

The cotton fibers that adhere to the cottonseed used to produce pulp for

cotton fiber papers.

Cotton Paper or Rag Paper

Paper made with a minimum of 25% cotton fiber. Cotton paper is also called

rag paper.

Couch Pit or Hog Pit

This is the pit below the couch roll. It collects water draining from this

section, wet wire trim and any wet broke generated due to the paper break

at the wire part. Couch pit has agitator (s).

Couch Roll

Couch roll serves the following functions 1) Main drive for the wire, 2)

Transfer the wet sheet from wire part to press part and 3) Removes water

(if suction type couch roll). Couch roll can be solid or suction type.

Cover Paper

Any wide variety of fairly heavy plain or embellished papers, which are

converted into, covers for books, catalogs, brochures, pamphlets, etc.

Good folding qualities, printability, and durability characterize it.


1. A defect in coated paper, caused by the separation of the coating layer

on the formation of fissures in the surface of the coating due to printing

or other converting process.

2. Crack at fold: Fissures in the crease when any paper is folded

along a fold line. May be due to separation of coating or separation of

fibers. More prevalent when the paper has been over-dried. In boards it

may occur along score-folds even though the scoring has been done to

minimize cracking at the fold. The term is also applied when coatings

crack without fiber failure during a folding operation.

Creamwove Paper

Medium brightness paper now mainly used for computer stationery purposes

or school children note books.


1. Deformation remaining from a fold over.

2. Cross direction wrinkles (Washboard): Fold over of a web in the

cross machine direction, giving a crease running in the machine direction.

3. Blade crease: A crease essentially in the machine direction

devoid of coating in the creased area.

4. Calender Crease: Usually a sharp crease caused by passage through

the Calender of a crease or of a fold generated at the Calender; often cut

through when it is preferable to call it a Calender out.

5. Smoothed crease: A flattened-out crease running mainly in the

machine direction. Can occur at the wet press section, dryer (dryer

wrinkles), size press, winder or sheeter.

Crepe Paper

A light weight paper, normally colored, with crinkly finish used for party



The operation of crinkling a sheet of paper to increase its stretch and


Crescent Former

Sheet forming section in a tissue machine, with the pulp suspension

jet-out of the headbox flowing between a felt and a wire both moving at

the same speed.


A defect in linerboards caused by the separation of the liner ply and/or

the formation of fissures (cracks) in the surface of the liner during


Cross-machine Direction

A direction perpendicular to the direction of web travels through the

paper machine.


A condition of a dried ink film, which repels another ink printed on top

of it.


A term used in the measurement of pulpwood, i.e. 100 cubic feet of solid

wood, bark excluded. One cunit corresponds to 2.83 cubic meter of wood.

Also see Cord


Tendency of paper by itself to bend or partly wrap around the axis of one

of its directions. For more details on Curl, please read Curl Basics by

Chuck Green.


A customark is a watermark made with a rubber printing plate treated with

a tranparentizing solution that leaves a mark in the paper. This process

produces a wire appearance in which the mark is lighter than the

surrounding paper. It can be produced in smaller quantities and at a lower

price than a genuine watermark, which requires a dandy roll.

Cut Sheet

Paper cut in sheets (letter, legal, A, B or any other standard size) to be

used in printer, photocopier, fax machines etc.


A machine in the Finishing House of a paper mill, used for converting

paper from reel to specific sheet sizes.

Cutter Dust

Small loose paper particles which chip out of the edges of a sheet of

papers as it is cut by the chopping blade and/or disc knives on a sheet


Cutting (Refining)

A refining or beating action that splits the fibers in to two or more


Cylinder Mould or Cylinder Machine

It is a type of papermaking machine. Wire-covered cylinders are rotated

through a vat of pulp, and paper is formed as the water drains from the

cylinder. Cylinder machines are used primarily to manufacture paperboard.

Multi-cylinder machines produce multi-layered paperboard (one layer for

each cylinder).


Damask Paper

Paper with a finish that resembles linen.

Damp Streaks

Streaks caused by uneven pressing of drying during paper manufacturing.


The process of keeping the non-image areas of lithographic plates to be

ink repellent by applying aqueous Fountain solution to the plate from the

Dampening system.

Dandy Roll

A hollow wire covered roll that rides on the paper machine wire and

compacts the newly formed wet web to improve the formation and if required

to impart watermark or laid finish the paper.


Pressing letters or illustrations into a sheet of paper using a metal or

plastic die to create a depressed (debossed) image.

Decalcomania Paper

A type of transfer paper that allows the transfer a printed image to

another object such as glass. Also called a decal.

Deciduous Trees

Broad leafed or hardwood trees which lose their leaves in fall such as

birch, maple etc.


A drum type filter used for pulp thickening.


The width of the wet sheet as it comes off the wire of a paper machine.

Also defied as the wood frame resting on or hinged to the edges of the

mould that defines the edges of the sheet in handmade papermaking or strap

or board on the wet end of a paper machine that determines the width of

the paper web.

Deckle Edge

The untrimmed, feathery edges of paper formed where the pulp flows against

the deckle.


A device that removes entrained and dissolved air from dilute stock

furnish by applying vacuum as the stock is sprayed into an open chamber,

usually at the outlet of cleaners.


A device on a web press or sheeter used to remove paper curl.


Separation of wood fibers by mechanical and/or chemical means.


Deflaker mechanically treat the fiber flakes and bundles of fibers in the

stock in order that they are broken down into individual fibers in a

suspension if possible. This is done for a number of reasons and in a

number of positions within the system. It can be installed to reduce

remaining flakes after a pulper, in the broke system to reduce flakes

going back to the machine from the broke pulpers and can also be used in

the final stages of a screening system in a recycled fiber line to treat

the concentrated rejects and the flakes contained within it.

Degree of Polymerization (DP)

As applied to cellulose, refers to the average number of glucose unit in

each cellulose molecule of a pulp sample. Usually determined by the CED

viscosity test.

Deinked Pulp (DIP)

Paper pulp produced by deinking of recovered paper


The process of removing inks, coatings, sizing, adhesives and/ or

impurities from waste paper before recycling the fibers into a new sheet.

Deinking Cell

A vessel or chest used to treat recycled paper with chemical to remove



The separation of the layers of a multiplex paper/paperboard.


The removal of lignin, the material that binds wood fibers together,

during the chemical pulping process.


Material that has the ability to absorb enough moisture from the

surrounding atmosphere to revert it to a liquid form. Examples of

deliquescent include calcium chloride and ammonium nitrate.


A sensitive photoelectric instrument that measures the density of

photographic images or of colors. Used in quality control to accurately

determine the consistency of color throughout the run.


Reducing the resin (pitch) content of wood prior to cooking either by

storage or using bleaching chemicals to reduce the resin content in pulp.

Diazo Base Paper

The process involves coating of paper with Diazo solutions and a coupler.

This is exposed to ultra violet rays coming through the image. The final

print is developed by making the coating alkaline. In some cases it is

developed by ammonia vapor.


The reaction vessel in which wood chips or other plant materials are

cooked with chemical to separate fiber by dissolving lignin.

Digital Printing

1. Printing by imaging systems that are fed imaging information as digital

data from pre-press systems.

2. Computer –to-plate Systems, which use printing plates, or other

images carriers that do not require intermediate films.

3. Computer-to-print (Plateless): Systems that produce reproductions

directly on the substrate without the need for intermediate films or


A. Electronic printers: Electrophotographic printers, for black or

single color, used for short-run variable information and on-demand book


B. Color copiers: Usually Electrophotographic printers, for spot or

four color process printing, used for making one or several copies of spot

or four color process subjects.

C. Electronic printing systems: Electrophotographic, magnetographic,

monographic, field effect, ink jet or thermal transfers printing. For

One-color, four color process or up to six-color printing. Used for some

degree of variable information, on-demand. Examples of use are direct

mail, temporary product labels for trade shows, billboard posters and the


Dimensional Stability

The ability of paper or paperboard to maintain size. It is the resistance

of paper to dimensional change with change in moisture content or relative

humidity. Dimensional stability is essential for keeping forms in

registration during printing and keeping sheets from jamming or wrinkling

on press or in laser printers.


A group of 75 chlorinated compounds. Dioxins are formed in a complex

process, where chlorine combines with other additives during bleaching..

Direct Cooking

Batch cooking in which digester contents are heated by blowing steam

directly into the digester.

Direct Dye

Dye molecules that are sufficiently large and planar that they tend to

remain on a fiber surface without need of a fixative. Direct dyes have

moderate lightfastness but duller shades


Dependency of a given paper property on the orientation of the fiber in

paper e.g. CD or MD.

Directory Paper

A light weight grade of catalog or printing paper with good strength, high

opacity and good printability. It is made from a mixture of bleached

chemical, semi-chemical, CMP and recycled fiber and used for printing

telephone directory.


Dirt in paper consists of any imbedded foreign matter or specks, which

contrast in color to the remainder of the sheet.

Dirt Count

The average amount of dirt specks in a specific size of paper area. Both

virgin sheets and recycled sheets have “dirt,” although recycled paper

usually has a slightly higher dirt count than virgin paper. However, it

rarely affects recycled paper’s quality and use.


Substances such as phosphates or acrylates that cause finely divided

particles to come apart and remain separate from each other in suspension.


Following the deinking process of waste papers, residual ink particles are

dispersed into tiny bits that are usually invisible to the eye. Bleaching

the fibers helps to remove the last of the inks and improve paper


Displacement Washing

An event of pulp washing in which washing liquid displaces free liquor

from a pulp bed in order to improve the washing; enables washing with

reduced amount of water.

Dissolving Pulp

A high purity special grade pulp made for processing in to cellulose

derivatives including rayon and acetate.

Doctor Blade

Thin metal plate or scraper in contact with a roll along its entire length

to keep it clean. Blades are also used for creping.

Document Paper

Document paper is paper with a high ageing resistance. It is woodfree but

may also contain rags or be fully made from rags and is used for documents

that have to be preserved for a longer period.

Document Paper

Document paper is paper with a high ageing resistance. It is woodfree but

may also contain rags or be fully made from rags and is used for documents

that have to be preserved for a longer period.

Double Coating

Coating of paper or paperboard twice on one or both sides.

Down Cycling

Every time cellulose fibers are recycled they deteriorate slightly and

become contaminated, so the new product is of lower quality than the

original product which went to form the waste; the progressive

deterioration of fibers means that there is a limit to the number of times

they can be recycled, thus the term down cycling is used as a more

accurate description of recycling.

Drainage or Dewatering

Removal of water from wet web during formation of paper sheet.


Difference in speed between two adjacent section of the paper machine.

Drawing Paper

Dull finished paper that is of good quality and stable enough to withstand



The solids which settle down in the clarifiers in the Causticizing


Drum Reel

The reel drum (also called a “pope reel”) is motor driven under sufficient

load to ensure adequate tension on the sheet coming from the calendars.

The web wraps around the reel drum and feeds into the nip formed between

the drum and the collecting reel.

Drum Washer

One type of pulp washers; uses pressure gradient and filtration for

dewatering and displacement.

Dry Coating

Coating method in which a binder is applied to the paper surface followed

by dry coating pigment.

Dry End

That part of the paper machine where the paper is dried, surface sized,

calendered and reeled.

Dry Line

The dry line is the location on a Fourdrinier paper machine forming

section where the appearance of the wet web of paper changes abruptly.

Before the dry line the furnish has a glossy, wet appearance. After the

dry line the wet web appears dull. The optical change is related to the

effect of fibers poking through the air-water interface. On a

well-adjusted paper machine the dry line ought to be straight. Increased

refining and lower freeness of the pulp tend to move the dry line in the

direction of the couch. Chemicals that promote drainage tend to move the

dry line in the direction of the slice.

Dry Offset

Uses a rotary letterpress plate on an offset press. Because the image is

relief, the method requires no dampening. Image is transferred to a rubber

blanket, then to paper.

Dryer Felt

A continuous cotton and or synthetic belt and used in the dryer section of

a paper machine to press and maintain positive contact of the web against

the surface of the dryer cylinder.

Dryer Screen

A type of dryer felt made of synthetic material, with very high open area

to provide easy escape to vapors formed due to water evaporation. Dryer

screens are used in the later part of dryer section where paper is >60%

dry to avoid any screen impression.


This is the final stage of water removal from wet web of the paper formed

on wire. After pressing the moisture content of the web is apprx. 40-45%.

The remaining water (up to 95% dryness) is removed by evaporation . This

is done by moving the web around a series of steam heated iron drums in

the dry end of the paper machine.

Duplex Bag

Two-ply bags.

Duplex Board

Paperboard made with two plies or layers. Normally two layers are formed

and joined together at wire part.

Duplex Paper

Paper made with two plies or layers. Normally two layers are formed and

joined together at wire part.


Loose flecks of fiber, filler and/or coating on the paper that sometimes

sticks to the printing blanket and prevents ink from reaching the paper



A chemical compound having the ability to absorb visible light over a

certain range of wavelengths so that the diffusely reflected light appears

colored. Dye can be basic, acidic or direct.


Edge Crush Resistance

The amount of force needed to crush on-edge of combined board is a primary

factor in predicting the compression strength of the completed box. When

using certain specifications in the carrier classifications, minimum edge

crush values must be certified.

Edge Cutter

Device comprising two jets of water which are adjustable across the wire

and which divide the wet web on the wire lengthwise so that the edges may

be removed, generally at the couch. In this way they control the width of

the web going forward from the wire part and give it comparatively clean


Effective Alkali

Caustic (NaOH) and one half of Sodium sulfide (05*Na2S) expressed as Na2O

in alkaline pulping liquor.


Waste backwater and rejects from which fiber is recovered prior to

discharge from the mill.

Electric Resistivity

Resistivity characterizes how a sheet of paper accepts and holds a charge.

Since the electrostatic processes uses an electrical charge to form the

print image, the electrical properties of the sheet are important to the

overall imaging process.

Electrical Grade Paper

Strong, pin-hole free paper, sometimes impregnated with synthetic resins

and made from unbleached Kraft pulp. Electrical insulating paper must

neither contain fillers nor conductive contaminants (metals, coal, etc.)

nor salts or acids. Lava stone bars are used on rotor and stator to avoid

any metal contamination. Cable papers, that are wound around line wires in

a spiral-like fashion, are electrical insulating papers with a

particularly high strength in machine direction. Electrical grade papers

include cable papers, electrolytic papers and capacitor paper.

Electro photography

A printing process that uses principles of electricity and electrically

charged particles to create images – e.g., photocopiers and laser


Electronic Printing

Photocopiers, ink jet, laser printers and other similar printing methods

that create images using electrostatic charges rather than a printing


Electrostatic Precipitator (ESP)

Used to clean up flue and process gases. Removes 99.5-99.8% of dust

particles emitted from recovery boilers, lime kilns and bark-fired


Elemental Chlorine Free (ECF)

ECF papers are made exclusively with pulp that uses chlorine dioxide

rather than elemental chlorine gas as a bleaching agent. This virtually

eliminates the discharge of detectable dioxins in the effluent of pulp

manufacturing facilities.


A property of paper that allows it to stretch.


Pressing a shape into a sheet of paper with a metal or plastic die,

creating a raised (embossed) image.

Emulsion Coating

Coating of paper with an emulsion containing plastic or resin.


A general term referring to coated paper that has a higher basis weight

than coated publication (magazine) paper but a lower basis weight and

caliper than coated cover paper.

End-leaf Paper

Strong, fine quality papers, either plain or coated and sometimes colored

or marbled used at both ends of a book. Also called sheets.

Engine Sizing

Old term used for beater sizing when sizing chemicals used to be added in

Engine or Beater.

English Finish

A smooth-finished, machine made and calendered book paper. It is soft,

dull and pliable. Normally used for letterpress printed magazines.


A printing process using intaglio, or recessed, plates. Made from steel or

copper, engraved plates cost more than plates used in most other printing

processes, such as lithography. Ink sits in the recessed wells of the

plate while the printing press exerts force on the paper, pushing it into

the wells and onto the ink. The pressure creates raised letters and images

on the front of the page and indentations on the back. The raised

lettering effect of engraving can be simulated using a less costly process

called thermography.

Entrained Air

Entrained air consists of bubbles that are small enough (say less than 1

mm) to move along with the fibers.

Envelop Paper

The paper made specifically for die cutting and folding of envelopes on

high-speed envelop machine.

Environmental Stewardship Policy

A formalized mission statement establishing companywide green objectives

for both employees and customers.

Environmentally Preferable Paper (EPP)

EPP should have at least two of the following three characteristics:

1. 30% or more Post Consumer Recycled Content

2. TCF Bleaching

3. Forest Stewardship Council certified Forest Management for virgin

fiber sources.


A protein that has the ability to direct or catalyze a chemical reaction.

Enzyme Bleaching

Bleaching technique in which cooked and oxygen-delignified chemical pulp

is treated with enzymes prior to final bleaching. Allows pulp to be

bleached without chlorine chemicals.

Equilibrium Moisture Content

The moisture content of a paper that has reached a balance with the

atmosphere surrounding it, i.e. in a condition in which it will neither

give up nor absorb moisture

Equivalent Black Area

Of a dirt speck is defined as the area of a round black spot on a white

background of the TAPPI Dirt Estimation Chart which makes the same visual

impression on its background as does the dirt speck on the particular

background in which it is embedded.


A grass from North Africa which makes a soft, ink receptive sheet.

Ethers Pulp

Generally these are high purity, high viscosity pulps that are swollen in

sodium hydroxide initially, followed by reaction with organic epoxides or

chlorides like ethylene oxide or methyl chloride to form an organic

polymer called cellulose ethers (methyl cellulose, hydroxyethyl cellulose,

carboxymethyl cellulose, etc.). Cellulose ethers are used for thickening

of fluids such as toothpaste, ketchup, shampoos, diet drinks and hundreds

of other applications.

Extended Cooking

Method of cooking pulp to low lignin content, thereby reducing the need

for bleaching chemicals.

Extensible Kraft

Very strong virgin Kraft papers which stretches (approximately 6%) more in

MD and tears less easily than regular Kraft paper.

External Fibrillation

A refining action that results in partial detachment of fibrils from outer

layer of a fiber.


Any number of different compounds in biomass that are not an integral part

of the cellular structure. The compounds can be extracted from wood by

means of polar and non-polar solvents including hot or cold water, ether ,

benzene, methanol, or other solvents that do not degrade the biomass

structure. The types of extractives found in biomass samples are entirely

dependent upon the sample itself

Extruded Coating

Coating applied to paper or board using an extruder.

Extrusion Coated Board

Board that has been covered with a continuous layer of a thermoplastic

material, typically polyethylene or polypropylene, by the extrusion

coating process i.e. where a thermoplastic material is melted and forced

through a narrow slot onto a moving web of board.


Fabric Press

Paper machine wet press that uses a special multiple weave fabric belt

sandwiched between the regular felt and the rubber covered roll,

increasing the capacity to receive and remove water from the nip between

the rolls.

Falling Film Evaporator

A type of heat exchanger used for concentrating a solution consisting of a

non-volatile solute and a volatile solvent; solution flows downward on the

heat exchange surface by gravity; the heat exchange surface is typically a

bundle of plates, lamellas or tubes; commonly used in pulp mills and

chemical recovery process.

Fan Pump

A high flow rate, low head pump used to pump diluted stock to paper

machine headbox.


Continuous multiple ply form manufactured from a single wide web which is

folded longitudinally.


A dimensional change in paper associated with its passage through a

printing unit. In web offset printing it is the increase in web width

after each blanket impression.

Fax Base Paper

It is first coated with photo conductive zinc oxide on which images are

exposed. Hence electrical conductivity / resistivity is to be controlled

to ensure that the image is not conducted through the paper to the other



The tendency of liquid ink to spread along the paper fibers so that the

image produced does not have sharp, clean edges.


A woven cloth used to carry the web of paper between press and dryer rolls

on the paper machine.

Felt Finish

Surface characteristics of paper formed at the wet end of a paper machine,

using woven wool or synthetic felts with distinctive patterns to create a

similar texture in the finish sheets.

Felt Mark

Imprint left on the paper by one or more of the felts used in making the

paper. The mark may be wanted or unwanted and special effects can be

introduced in this way.

Felt Side

The side of the paper which does not touch the wire on the paper machine.

The “top side” or felt side is preferred for printing because it retains

more fillers.

Fiber Axis Ratio

Ratio of fiber width to fiber thickness.

Fiber Coarseness

Weight per unit length of fiber.

Fiber Cut

A fiber cut is a short, straight cut located on the edge of the web,

caused by a fiber imbedded in the web of paper.

Fiber Debris

Pieces of material which has been separated from the main body of the


Fiber Floc

Fibers that have agglomerated as a result of poor formation.

Fiber or Fibre

The slender, thread-like cellulose structures that forms the main part of

tree trunk and from separated and suitably treated, cohere to form a sheet

of paper.

Fiber Orientation

Refers to the alignment of the fibers in the sheet.


Board made from defibrated wood chips, used as a building board.

Fibrillae or Fibrils

String-like elements that are loosened from the paper fibers during the

beating process. They aid in the bonding processes when paper is being



A structural change occurring in the walls of chemical pulp fibers during



Any inorganic substance added to the pulp during manufacturing of paper.

Filter Paper

Unsized paper made from chemical pulp, in some cases also with an

admixture of rags, sometimes with a wet strength finish. Filtration rate

and selectivity, which are both dependent on the number and the size of

the pores, can be controlled by specific grinding of the pulps and



The effluent from the washing or filtering process.

Fine Papers

Uncoated writing and printing grade paper including offset, bond,

duplicating and photocopying.


Small particles fiber defined arbitrarily by classification.


The surface characteristic of a sheet created by either on-machine or

off-machine papermaking processes. Popular text and cover finishes include

smooth, vellum, felt, laid, and linen.


The trimming, winding, rewinding and packing of paper rolls or trimming,

cutting, counting and packing of paper sheets from parent roll.

Finishing Broke

Discarded paper resulting from any finishing operation.

First Pass Retention

First-pass retention gives a practical indication of the efficiency by

which fine materials are retained in a web of paper as it is being formed.

First-pass retention values can be calculated from just two consistency

measurements, the headbox consistency, and the white water consistency.

There is a very wide diversity of first-pass retention on different paper

machines, from less than 50% to almost 100%. The key rules that

papermakers follow are that (a) first-pass retention should have a steady

value, and (b) that value should be high enough to avoid operational

problems or an excessively two-sided sheet. Some operational problems that

can be caused by low values of first-pass retention are increased

frequency of deposit problems, filling of wet-press felts, poor drainage,

and unsteady drainage rates and sheet moistures.

Fish Eye

A paper defect appearing as glazed, translucent spot caused by slime,

fiber bundles, and/or improperly prepared chemical additives in the stock.


A strip of paper protruding from a roll or skid of paper. May be used to

mark a splice in a roll of paper or used to mark off reams in a skid.

Flame Resistant

Treatment applied to kraft paper to make it resistant to catching on fire

(not fire proof—will char but not burst into flame).


Spontaneous boiling and cooling of a liquid caused by the reduction of

pressure below the vapor pressure of the liquid. Flashing occurs in blow

tank during blowing.

Flat Crush of Corrugated Board

A laboratory test (Tappi T808 or T825) of a single wall combined board

specimen to measure its resistance to crushing forces from conversion and

handling. Test can also be an indicator of flute formation and the

presence of crushed or leaning flutes.


A form of rotary letterpress using flexible rubber or photopolymer plates.

Flexural Rigidity

The measurement of a combined board resistance to flexing. Combined with

ECT box perimeter and flute type, it is key to predicting box compression

resistance or static load resistance (Tappi T566).

Flocked Paper

Paper with a velvet-like, smooth unglazed surface.

Flotation Cell

Main equipment of Flotation Deinking, Large number of tiny air bubbles are

injected into the cleaned pulp, the free ink particles attach themselves

to these bubbles and float to the surface where it is skimmed off and


Flotation Deinking

Using flotation method for removing ink from paper during the de-inking


Flotation Dryer

Non contacting dryer used in pulp drying or coating applications, drying

is achieved by passing sheet between two dryer hoods where hot dry air is

impinged onto the sheet and the moisture is evaporated and removed by an

air system.*

Fluff Pulp

A chemical, mechanical or combination of chemical/mechanical pulp, usually

bleached, used as an absorbent medium in disposable diapers, bed pads and

hygienic personal products. Also known as “fluffing” or “comminution” pulp

Fluorescent Dye

A coloring agent added to pulp to increase the brightness of the paper. It

may give a slight blue or green cast to the sheet.

Fluorescent Inks

Printing inks that emit and reflect light. Generally, they are brighter

and more opaque than traditional inks, but they are not color fast, so

they will fade in bright light over time. Their metallic content will also

affect dot gain and trapping.

Fluorescent Paper

Paper coated or surface treated with fluorescent dye to make it glow in

dark. Used for labels, posters and decorative application.

Fluorescent Whitening Agent

Also referred to as an “optical brightener.” A chemical compound when

expose to a light containing an ultraviolet component will absorb and

re-emit light in the blue spectrum or in other words fluoresce. FWA’s will

enhance brightness and blueness quality of white paper.


One of the wave shapes pressed into corrugated medium. Flutes are

categorized by the size of the wave. A, B, C, E and F are common flute

types, along with a variety of much larger flutes and smaller flutes.

Flute (A,B,C,E,F&G)

These letters define the type of corrugated material in terms of the

number of corrugations per unit length and the height of the corrugations

– specifically these are:


Corrugations per metre

Height of corrugation (mm)


105 – 125

4.5 – 4.7


150 – 185

2.1 – 2.9


120 – 145

3.5 – 3.7


290 – 320

1.1 – 1.2


410 – 420

0.7 – 0.8


550 – 560

0.5 – 0.6

Fluted Edge Crush

Measures the edgewise compression strength of corrugating medium using a

fluted test specimen per Tappi T824.


Waves or corrugation in heat-set web offset prints that runs in the press


Fly Leaf/Shaving

Trim scrap from printing operation.


C1S paperboard designed for lamination to a foam backing for

point-of-purchase displays, posters, and signs.

Foil of Hydrafoil

The flat strip used to support wire. Only the leading edge of the wire

touches the foil. Foil helps in removing water by creating gentle suction

and also doctor the water removed in previous section.


Doubling up a sheet of paper so that one part lies on top of another.

Folding stresses the paper fibers. To create a smooth, straight fold,

heavy papers like cover stocks and Bristol need to be scored before

they’re folded.

Folding Boxboard

Single or multi-layer paperboard made from primary and/or secondary

fibers, sometimes with a coated front, used to make consumer packaging


Folding Strength or Folding Endurance

Folding strength is most important in currency paper. Multiple fold

strength is also important for paper used in books, maps, and pamphlets.

It’s far less important in one-fold greeting cards or envelopes, where

fold cracking is the vital consideration. Folding endurance or strength is

measured and reported in numbers.

Forest Stewardship Council-certified

Certification from an international non-profit which verifies responsible

forest practices.

Form Bond

A lightweight commodity paper designed primarily for printed business

forms. It is usually made from chemical wood and/or mechanical pulps.

Important product qualities include good perforating, folding, punching,

and manifolding properties. The most common end use for this grade is

carbon-interleaved multi-part computer printout paper, which is marginally

punched, cross-perforated, and fanfolded.


The dispersion of fibers in a sheet of paper. The more uniform and tightly

bound the fibers, the better the sheet will print and look. Close

Formation – Uniform distribution of fibers. Cloudy formation: A spotty,

non-uniform dispersion of fibers, the opposite of close formation.

Forming Board

Forming Board is the leading forming unit under the fabric closest to the

slice. The stock jet velocity, the impingement angle and the position of

the impingement onto the forming board will determine the water removal

and the activity produced at this point. Modern Forming Boards are stepped

to create activity at high speeds – this greatly enhances the formation.

Fountain Roller

The roller on a printing machine which initiates the supply of moisture to

the damping system.

Four-color Printing Process

A printing method that uses dots of magenta (red), cyan (blue), yellow,

and black to simulate the continuous tones and variety of colors in a

color image. Reproducing a four-color image begins with separating the

image into four different halftones by using color filters of the opposite

(or negative) color. For instance, a red filter is used to capture the

cyan halftone, a blue filter is used to capture the yellow halftone, and a

green filter is used to capture the magenta halftone. Because a printing

press can’t change the tone intensity of ink, four-color process relies on

a trick of the eye to mimic light and dark areas.

Each halftone separation is printed with its process color (cyan,

magenta, yellow, and black). When we look at the final result, our eyes

blend the dots to recreate the continuous tones and variety of colors we

see in a color photograph, painting, or drawing.


Named after its inventor, the Fourdrinier papermaking machine is

structured on a continuously moving wire belt on to which a watery slurry

of pulp is spread. As the wire moves, the water is drained off and pressed

out, and the paper is then dried.

Free Stock

Unrefined stock. Stock that, when drained under gravity, parts easily with

the water of suspension


A term used to define how quickly water is drained from the pulp. The

opposite of freeness is slowness. Freeness or slowness is the function of

beating or refining. Freeness and slowness reported in ml CSF and degree

SR respectively are also the measurement of degree of refining or beating.


Paper containing less than 10% mechanical wood pulp, which is true of

virtually all fine printing papers. Sometimes referred to as wood-free.

French Fold

A sheet printed on one side and folded first vertically and then

horizontally to produce a four-page folder.

Fruit Wrapping Paper

A lightweight tissue used for wrapping fruit for shipment. Sometimes

treated chemically to retard decay of the fruit with which it is in


Fully Bleached Pulp

Pulp that has been bleached to the highest brightness attainable (> 60



A blend of fibers, pigments, dyes, fillers and other materials that are

fed to the wet end of the paper machine.


Fibrous projections on the surface of a sheet of paper, caused by

excessive suction, insufficient beating or lack of surface sizing. Lint

appears in much the same manner but is not attached to the surface.


Gasket Board

A highly absorbent pulp board, which is chemically treated for use in

making gaskets.


Two or more parallel folds on a sheet of paper with the end flaps folding



Variation in ink gloss, density or color that are not part of the original

design, but appear as a repeat or ghost image associated with another area

of the copy.

Glassine Paper

A translucent paper made from highly beaten chemical pulp and subsequently


Glazed Paper

Paper with high gloss or polish, applied to the surface either during the

process of manufacture or after the paper is produced, by various methods

such as friction glazing, calendering, plating or drying on a Yankee



The property that’s responsible for a paper’s shiny or lustrous

appearance; also the measure of a sheet’s surface reflectivity. Gloss is

often associated with quality: higher quality coated papers exhibit higher


Gloss Mottle

Blotchiness or non-uniformity in the paper’s gloss (unprinted or printed).

Typically only visible at certain viewing angles. Usually attributable to

poor formation and heavy calendering.


Papers are differentiated from each other by their grade. Different grades

are distinguished from each other on the basis of their content,

appearance, manufacturing history, and/or their end use.


The direction in which most fibers lie in a sheet of paper. As the pulp

slurry moves forward on the papermaking machine’s formation wires, the

fibers tend to align themselves in the direction of movement. Binding

books parallel to the grain allows for a smoother fold then working across

the grain. Grain direction of sheet fed papers is usually indicated by

underlining the number, e.g., 23″ X -35″. On a web press, the grain

direction should run along the length of the paper web.

Grain Long

Grain running lengthwise along a sheet of paper.

Grain Short

Grain running widthwise along a sheet of paper.


Weight in grams of one square meter of paper or board (g/m2); also basis


Granite Paper

A paper containing a small percentage of deeply dyed fibers to give a

characteristic mottled effect.


A printing process that uses intaglio, or recessed, image carriers. The

image carrier, which is flat or cylindrical, moves through an ink pool. A

blade scrapes excess ink off the plane of the plate, leaving ink in the

recessed wells. A second cylinder presses the paper onto the plates, where

it picks up ink from the wells. The high speed of gravure presses and the

durability of the metal intaglio plates make gravure an economical

printing method suitable for large print runs (more than two million


Gravure Paper

Paper for gravure printing that has very low print roughness and good

wettability of gravure inks.

Gray Board

A homogeneous board made usually of mixed waste papers with or without

screenings and mechanical pulp on a continuous board machine, in thickness

less then 1 mm.

Greaseproof Paper

A protective wrapping paper made from chemical wood pulps, which are

highly hydrated in order that the resulting paper may be resistant to oil

and grease.

Green House Gases

Gases that provide an insulating effect in the earth’s atmosphere,

potentially leading to global climate change. These gases include carbon

dioxide, methane, nitrous oxide, ozone, and water vapor.

Green Fatigue

The eco-exhaustion experienced by those bombarded with green products,

services and news from advertisers, the media and companies.

Green Liquor

The liquor that results when the inorganic smelt from the recovery furnace

is dissolved in water is called “green” liquor.

Green Paper

Immature paper which has not been conditioned or had the opportunity to

mature naturally.


A term used to describe the perception by many consumers that they are

being misled on environmental practices of a company, or the benefits of a

company’s product or service.

Greenfield Mill

Mill or production facility built on undeveloped site.


A machine in which logs are defibrated against a revolving grindstone.

Groundwood Papers

A general term applied to a variety of papers made with substantial

proportions of mechanical wood pulp together with bleached or unbleached

chemical wood pulps (generally sulfite), or a combination of these, and

used mainly for printing and converting purposes.

Groundwood Pulps

A mechanically prepared (by grinding wood logs against a rough surfaced

roll rotating at very high speed) coarse wood pulp used in newsprint and

other low cost book grades where it contributes bulk, opacity, and

compressibility. Groundwood pulp is economical since all the wood is used;

however, it contains impurities that can cause discoloration and weakening

of the paper.

Guar Gum

A natural polymer that is used as a dry-strength additive, often as a

cationic derivative.


A machine used to trim stacks of paper, which works the same way the

original French guillotine worked. A cutting blade moves between two

upright guides and slices the paper uniformly as it moves downward.

Gummed Paper

The main ingredient in gypsum board is gypsum (calcium sulfate – Ca2SO4),

a mineral.. Board is lined with sheet of paper on both sides. This is used

for making panel boards for interior partitions, false ceiling etc.

Gurley Porosity

A method to measure the air permeability of paper by TAPPI method T536.

See “Air permeability.”

Gypsum Board

The main ingredient in gypsum board is gypsum (calcium sulfate – Ca2SO4),

a mineral.. Board is lined with sheet of paper on both sides. This is used

for making panel boards for interior partitions, false ceiling etc.


Half + Letter Fold

This fold is perfect for newsletters. An 11″ x 17″ sheet folded this way

has only one open side and fits into a #10 envelope. The newsletter looks

good and is easy to handle.

Half Fold

The half fold is commonly used for brochures and greeting cards. For cover

weight paper, a score is usually required to produce a smooth folded edge.

Half Tone

Picture with gradations of tone, formed by dots of varying sizes in one


Handmade Paper

A sheet of paper, made individually by hand, using a mould and deckle.

Hanging Paper

The raw stock used in making wall paper. The converter usually coats it

with a ground coat of clay, and then prints it with any decorative design


Hard Cook

Undercooked pulp with respect to target conditions.

Hard Pulp

Chemical pulp with a high lignin content.

Hard Sized Paper

Paper treated with high degree of internal sizing.


Wood from trees of angiosperms class, usually with broad leaves. Trees

grown in tropical climates are generally hardwood. Hardwood grows faster

than softwood but have shorter fibers compared to softwood.

Head Box or Flow Box or Breast Box

The part of the paper machine whose primary function is to deliver a

uniform dispersion of fibers in water at the proper speed through the

slice opening to the paper machine wire.

Heart Wood

The dark colored , center of a tree trunk, consisting of dormant wood.

Heat Seal Paper

Paper that has an adhesive coating applied to it that requires heat to

activate the adhesion properties.

Heat Set Web

An offset printing process done on a web of paper supplied in a roll. The

term heat set originates from the inks used in the process. They contain

high amounts of solvent flashed off in ovens to dry at very high speeds.

Web presses perfect or print both sides of the sheet simultaneously.

Heat Transfer Paper

The paper used in Thermal transfer printing (Sublimation printing).

Heat Transfer Paper

The paper used in Thermal transfer printing (Sublimation printing).


A constituent of woods that is, like cellulose, a polysaccharide, but less

complex and easily hydrolysable.

Herbaceous Plants

Non-woody species of vegetation, usually of low lignin content such as



An irregularity in the ink coverage of a printed page. Hickeys are caused

by paper or pressroom dust, dirt, or pick out on the printing blanket, all

of which prevent the ink from adhering to the paper surface.

Hi-Fi (High Finish) Paper

Machine calendered newsprint.

High Finish

Smooth finish applied to paper to improve the printing surface.

Hold Out

Resistance of paper surfaces to the absorption of ink. High Hold Out

offers higher resistance to ink absorption. Regular Hold Out allows

greater ink absorption.


The total carbohydrate fraction of wood — cellulose plus hemicellulose.


Printining process by which great continuous 3D depth is achieved using

textures and patterns.


A hood covering the paper machine drying section and designed for moist

air removal.

Hot Groundwood Pulp

Mechanical pulp produced by grinding logs that have been pre-treated with


Hot Melt

A type of glue or adhesive applied while hot/warm.


The prolonged beating or refining of cellulose pulp in water to reduce it

to a semi-gelatinous mass.

Hydrogen Peroxide Bleaching

A method in which pulp is bleached in an alkaline environment with

hydrogen peroxide (H2O2), sometimes using oxygen reinforcement. The method

considerably reduces the need for chlorine-containing chemicals in the

final bleaching of chemical pulps.


Having strong affinity for water.


Lacking affinity for water.


An equipment used to slush broke/paper in to pulp.


Having the property to absorb water vapor from the surrounding atmosphere.

Most of the papers (except glassine, greaseproof or wet strength etc.) are

hygroscopic in nature.



The absorption of liquid by a fiber without a corresponding increase in



Process of treating a sheet of paper with a chemical or wax so that the

treatment penetrates into the paper.

Impression Cylinder

The cylinder or flat bed of a printing press that holds paper while an

inked image from the blanket is pressed upon it.

Impression Watermark

Semi-genuine watermark made in the paper machine press section using

engraved rolls while the web is still wet.

Index Paper

A stiff, inexpensive paper with a smooth finish. The high bulk but low

weight of this paper makes it a popular choice for business reply cards.

Industrial Papers

A very general term, which is used to indicate papers manufactured for

industrial uses as opposed to cultural purposes. Thus, building papers,

insulating papers, wrapping papers, packaging papers, etc. would be

considered industrial papers.

Infra Red Drying

Electric or gas infra red dryers used to initially achieve immobilization

of the fluid coating and commence the drying process.


Printing inks are made up of pigment, pigment carrier and additives

formulated to reduce smudging, picking and other printing problems

associated with ink. The choice of ink depends on the type of paper and

printing process.

Ink Absorption

A paper’s capacity to accept or absorb ink.

Ink Coverage

The portion of the total surface area of the paper which is covered by

ink. The portion of the coverage usually is expressed in terms of percent

of ink coverage.

Ink Holdout

The way the ink pigment sits on the surface of the paper. Strong ink

holdout results in a sharp, bright image.

Ink Jet Printing

Printing process of an image or text by small ink particles projected onto

the paper surface.

Ink Tack

The body or cohesiveness of ink. The measure of tack as the force required

to split an ink film.

Insect Resistant

Paper treated with insecticide compounds to make it resistant to insect


Insider Liner

The liner bonded to the medium at the single facer. Called inside liner

because it is the inside facing of a corrugated box. Also called the

single face liner.

Insulating Board

A type of board composed of some fibrous material, such as wood or other

vegetable fiber, sized throughout, and felted or pressed together in such

a way as to contain a large quantity of entrapped or “dead” air. It is

made either by cementing together several thin layers or forming a

non-laminated layer of the required thickness. It is used in plain or

decorative finishes for interior walls and ceilings in thickness of 0.5

and 1 inch (in some cases up to 3 inches) and also as a water-repellent

finish for house sheathing. Desirable properties are low thermal

conductivity, moisture resistance, fire resistance, permanency, vermin and

insect resistance, and structural strength. No single material combines

all these properties but all should be permanent and should be treated to

resist moisture absorption.

Insulating Board

A type of board composed of some fibrous material, such as wood or other

vegetable fiber, sized throughout, and felted or pressed together in such

a way as to contain a large quantity of entrapped or “dead” air. It is

made either by cementing together several thin layers or forming a

non-laminated layer of the required thickness. It is used in plain or

decorative finishes for interior walls and ceilings in thicknesses of 0.5

and 1 inch (in some cases up to 3 inches) and also as a water-repellent

finish for house sheathing. Desirable properties are low thermal

conductivity, moisture resistance, fire resistance, permanency, vermin and

insect resistance, and structural strength. No single material combines

all these properties but all should be permanent and should be treated to

resist moisture absorption.


A method of printing in which an image or letter is cut into the surface

of wood or metal, creating tiny wells. Printing ink sits in these wells,

and the paper is pressed onto the plate and into the wells, picking up the


1. Gravure is considered an intaglio printing process.

2. In papermaking, watermarking from countersunk depressions in the dandy

roll to provide a whiter or denser design instead of increased


Integrated Mill

A mill which starts with logs or wood chips and first produces wood pulp

which it then processes to make paper or board.

Intermittent Board Machine

A machine for producing sheets of thick board by winding the web formed on

a Fourdrinier wire or cylinder mould (s) around a making roll to form a

sheet consisting of several layers. When the thickness is sufficient the

layers are cut, so forming a sheet which is removed from the machine for

drying and any further processing.

Internal Bonding Strength

Determines how strongly the coating is fused to the body stock. Caused by

long periods of hydration, paper with high internal bonding strength

resists picking during the printing process

Internal Fibrillation

Loosening of internal bond within a fiber.

Internal Sizing

Occurs when sizing materials are added to the water suspension of pulp

fibers in the papermaking process. Also known as Beater, or Engine sizing.

International Paper and Board Sizes

Also known as ISO sizes are widely used in metric countries. ISO standards

are based on a rectangle whose sides have a ratio of one to the square

root of 2 (1.414). No matter how many times a sheet of these proportions

is halved, each will retain the same constant proportions. There are three

ISO series A, B, and C.

The A Series: The A series is for general printed matter including

stationary and publications.

SIZE Millimeters

4A0 1682 x 2378

2A0 1189 x 1682

A0 841 x 1189

A1 594 x 841

A2 420 x 594

A3 297 x 420

A4 210 x 297

A5 148 x 210

A6 105 x 148

A7 74 x 105

A8 52 x 74

The B series: The B series is about half way between two A sizes. It

is intended as an alternative to the A series, used primarily for posters

and wall charts.

SIZE Millimeter

B0 1000 x 1414

B1 707 x 1000

B2 500 x 707

B3 353 x 500

B4 250 X 353

B5 176 x 250

B6 125 x 176

B7 88 x 125

B8 62 x 88

B9 44 x 44

B10 31 x 44

The C series: The C series is used for folders, post cards and

envelopes. C series envelope is suitable to insert A series sizes.

SIZE Millimeter

C0 917 x 1297

C1 648 x 917

C2 458 x 648

C3 324 x 458

C4 229 x 324

C5 162 x 229

C6 114 x 162

C7 81 x 114

C8 57 x 81

RA Series Formats

RA0 860 x 1220

RA1 610 x 860

RA2 430 x 610

RA3 305 x 430

RA4 215 x 305

SRA Series Formats

SRA0 900 x 1280

SRA1 640 x 900

SRA2 450 x 640

SRA3 320 x 450

SRA4 225 x 320


DL 110 x 220

C6 114 x 162

C5 162 x 229

C4 229 x 458

C3 324 x 458

ISO Brightness

The brightness of paper and board measured at a wavelength of 457

nanometers under standard conditions.

Ivory Board

High-quality board made in white or colors with a bright, clear

appearance, particularly used for visiting cards and similar high-class

printed work. Original Ivory Board was and still is made in Holland,

although the grade is made in many countries.


Japan Paper

An imitation of the Japanese vellum paper in which the fibers are very

long and have a very irregular formation, giving the surface a

characteristic mottled effect. Used for greeting cards, novelties and

artistic printing of various types. The real Japanese paper is made from

very long native fibers, such as paper mulberry, mitsumata, etc.

Jet to Wire Speed Ratio

Papermakers adjust the jet-to-wire speed ratio to fine-tune the paper

structure. The “jet” is the narrow stream of dilute stock that comes out

of the headbox slice opening. The “wire” is the continuous belt of forming

fabric. Often it is possible to improve the uniformity of paper by running

jet-to-wire speed ratio as one. “Rushing the sheet” means that the jet

speed is higher than the wire speed. “Dragging the sheet” means that the

wire speed is higher than the jet speed. Especially in the case of

dragging, increasing values of jet-to-wire speed ratio tend to align

fibers in the machine direction. For square sheet (paper which has same

strength properties in CD and MD), jet to wire ratio should be kept as

close to one as possible.

Job Lot

Out of specification, defective or discontinued types of paper made in

small quantities for special orders and sometimes sold at lower than

regular prices.


To shake a stack of papers, either on a machine or by hand, so that the

edges line up. Finisher jog the paper to remove any improperly cut sheet.

Printers jog the paper to get rid of any dust or particles and to ensure

proper feeding into the press.

Jumbo Roll

A roll of paper, direct from the paper machine, wound on a machine winder

spool as distinct from rolls that have been slit and rewound on cores.

Jute Paper

Any paper made from jute fiber or burlap waste. The fiber is long and the

paper has high strength and good folding properties. The name is becoming

misleading because of its application to fiber furnishes which contain

little or no jute.



White clay used as an additive and filler in paper and coating made up

chiefly of minerals of the kaolinite type.

Kappa Number

A term used to define the degree of delignification. Modified permanganate

test value of pulp which has been corrected to 50 percent consumption of

the chemical. Kappa number has the advantage of a linear relationship with

lignin content over a wide range. Kappa Number x 0.15% = % lignin in pulp


An annual agricultural plant, native of India, which has along fiber in

the bark that, is suitable for papermaking.

Kiss Impression

The lightest impression (anilox and plate to substrate) possible to

properly reproduce the image on paper.


Vibratory screens used for separating knots, uncooked chips and shives

from the pulp at the blow tank.

Knotter Pulp

Pulp made from the rejects from chemical pulp screening.


The most common fiber used in Japanese papermaking, it comes from the

mulberry tree. It is a long, tough fiber that produces strong absorbent


Kraft Bag Paper

A paper made of sulfate pulp and used in the manufacture of paper bags. It

normally has a greater bulk and a rougher surface than the usual kraft

wrapping paper.

Kraft Paper

A paper of high strength made from sulfate pulp. Kraft papers vary from

unbleached Kraft used for wrapping purposes to fully bleached Kraft used

for strong Bond and Ledger papers.

Kraft Pulp

Chemical wood pulp produced by digesting wood by the sulfate process

(q.v.). Originally a strong, unbleached coniferous pulp for packaging

papers, kraft pulp has now spread into the realms of bleached pulps from

both coniferous and deciduous woods for printing papers

Kraft Waterproof Paper

A highly moisture resistant paper made of sulfate pulp and treated with

moisture repellent material such as paraffin wax or asphalt and used for

wrapping purposes.


Paperboard of grammages of 120g and more, generally made from bleached or

unbleached sulfate pulp and used as an outer ply in corrugated board.



A separate slip or sheet of paper affixed to a surface for identification

or description. For fiberboard boxes, includes: Full Label, Mailing or

shipping Label, Spot Label and UPC (Universal Product Code) Label.

Label Paper

Mostly one-side coated papers which must be printable in 4-colour offset

and gravure printing. These papers are usually suitable for varnishing,

bronzing and punching and sometimes also feature wet strength and alkali

resistance (See “Wet strength and alkali resistant paper”) in order to

en-sure the removal of the labels e.g. in the bottle rinsing machines of



A finished produced with a dandy roll having closely spaced wires.

Laid Lines

A continuous watermark consisting of very close parallel lines, generally

associated with spaced lines (chain lines) at right angles to these.

Laid Paper

Paper that has a laid finish. Commonly used for letterheads and

personalized stationary.

Laminated Linerboard

Two or more plies of linerboard adhered to one another for increased

structural stability.

Laminated Paper

A paper built up to a desired thickness or a given desired surface by

joining together two or more webs or sheets. The papers thus joined may be

alike or different; a totally different material, such as foil, may be

laminated with paper.


A machine that adheres multiple plies of paper or fiberboard. May be used

to adhere full labels to a facing, or, for enhanced structural properties,

multiple facings, corrugating mediums or sheets of combined board.

Laser Printing

Xerographic printing where a modulated laser ray is projected on to a

photoconductive cylinder or belt by a rotating mirror. The laser serves to

product the electrostatic latent image, which is developed with toners.


A device at the end of cutter for jogging sheets in to a square pile.


Water that has as a component of dissolved matter accumulated as a result

of passing through material. e.g. rain water passing through waste dump.

Ledger Paper

A strong paper usually made for accounting and records. It is similar to

Bond paper in its erasure and pen writing characteristics.


Abbreviation for “Leadership in Energy and Environmental Design”, a green

building rating system that encourages global adoption of sustainable

green buildings and development practices.

Letter Fold

This common fold, used for mailings and brochures, is much like a letter


by hand for inserting in an envelope. The letter fold produces a

self-contained unit,

easily handled by automated envelope inserters.

Letter Press

A process of printing in which raised images are coated with ink and

pressed directly onto a paper or paperboard surface

Lick Coating

A light form of mineral coating, achieved by supplying the surface sizing

press of the paper making machine with coating material instead of normal

surface sizing solution.


Analysis of a product from production stage to disposal.

Light Weight Coated (LWC)

Coating applied at 7-10 g/m2 on one or both sides of the paper

Light Weight Coating (LWC)

Coating applied at 7-10 g/m2 on one or both sides of the paper.

Light Weight Paper

Papers having a grammage (basis weight) normally less than 40 g/m2.


The speed at which a pigment or colored paper fades in sunlight. or

How permanent a color is or how unaffected by light it is.


A complex constituent of the wood that cement the cellulose fibers

together. Lignin is brown in color. Lignin is largely responsible for the

strength and rigidity of plants, but its presence in paper is believed to

contribute to chemical degradation. To a large extent, lignin can be

removed during manufacturing.


Refers to plant materials made up primarily of lignin, cellulose, and



Paper that has the same appearance and characteristics on both sides.

Lime Sludge or Sludge

Sludge of calcium carbonate (CaCO3) formed during preparation of white

liquor in the chemical recovery process.

Linear Paper

A watermarked sheet with lines to guide the user.

Linen Finish

A finished paper that has an overall embossed pattern on the surface

resembling the look and feel of linen cloth, and one manufactured with

engraved embossing rolls.

Linen Paper

Paper with a finish that resembles linen cloth.


A creased fiberboard sheet inserted as a sleeve in a container and

covering all side walls. Used to provide extra stacking strength or

cushioning. Also used as a short hand for “linerboard” or facing.”


The inner and outer layers of paper that form the wall of a corrugated


Lines Per Inch (LPI)

The number of lines in an inch, as found on the screens that create

halftones and four-color process images (for example, “printed 175-line

screen”). The more lines per inch, the more detailed the printed image

will be. With the demand for computer-generated imagery, the term “dots

per inch” (which refers to the resolution of the output), is replacing the

term “lines per inch.”


Loosely bonded fibers at the paper surface that attached to the plate or

blanket of the printing machine.


A generic term for any printing process in which the image area and the

non-image area exist on the same plate and are separated by a chemical

repulsion. Usually oil based offset printing.

Litmus Paper

An absorbent paper saturated with, litmus, a water-soluble dye extracted

from certain lichens. The resulting piece of paper becomes a pH indicator,

used to test materials for acidity. Blue litmus paper turns red under

acidic conditions and red litmus paper turns blue under basic conditions,

the color change occurring over the pH range 4.5-8.3 (at 25°C).


Addition of fillers

Look Through

The appearance of the paper when held up to transmitted light. It

discloses whether the formation is even and uniform or lumpy and ‘wild’.

For book publishing papers, a regular, even look through is desirable,

indicating a well made, uniform sheet


M Weight

The weight of one thousand sheets of paper, any size; or double the ream


M2 Yield/Ton

A measure of the surface area of paper/paperboard which is obtained from a

ton of paper.

Machine Chest

Usually the last large chest or tank that contains thick-stock pulp before

it is made into paper.

Machine Clothing or Paper Machine Clothing

Fabrics of various types employed on the paper machine to carry the web

and perform other functions. It includes the machine wire, dandy roll

cover, press felts and dryer felts etc., which may be composed of natural

or synthetic materials.

Machine Crepe

Crepe paper produced on the paper machine, and not as a secondary option.

Machine Direction

The direction of the web through the paper machine.

Machine Finish

Finished produced on the paper as it leaves either the machine or the

calender stack. For increased printability, or smoothness when used as a

liner, etc.

Machine Glazed

Machine glazed. Paper with a glossy finish on one side produced on the

paper machine by a Yankee cylinder.

Machine Speed

The rate at which paper machine runs, expressed as m/min or ft/min.

Machine Width

Width of the paper web in the paper machine.

Manifold Paper

A light weight bond paper used for making carbon or manifold copies or for

airmail correspondence.


A semi-bleached chemical sulfate paper. Not as strong as Kraft, but have

better printing qualities.

Manufacturing Order

Also known as making order. A quantity of paper manufactured to custom

specifications, such as a special weight, color, or size not available as

a standard stocking item.

Map Paper

Paper used for making maps must be subject to minimum change in dimensions

with moisture to avoid poor register of colors. Wet strength properties

are often demanded.


Addition of strongly stained fibers to the stock to give the paper a

marbled appearance.

Market Pulp

Pulp which is made to be used elsewhere for the production of paper.

Usually dried to reduce freight costs but may be “wet lap” ( 50% water).

Matrix Paper

A bulky, absorbent paper used for making molds for casting printing

plates. It must have high compressibility and strength when wet, and

become rigid and hard when molded and dried. It is sometimes made by

allowing a thin web to wind up on the cylinder of a wet-machine and

cutting it off when of the proper thickness.

Matte Finish

A dull, clay-coated paper without gloss or luster.

Maximum Trimmed Width

The greatest width of usable paper that is possible to make on a given

paper making machine, i.e. the full width less the necessary trim to give

clean edges. There is 3-10% width shrinkage (depending on freeness of

stock) in dryers. It is not possible to specify sizes which, in aggregate,

exceed this width.

Mechanical Paper

This paper contains mechanical pulp, thermomechanical pulp (TMP) or

chemithermo-mechanical pulp (CTMP) and also chemical pulp. The shares of

chemical and mechanical pulp vary depending on the application. Highly

mechanical papers such as newsprint tend to yellow more rapidly if exposed

to light and oxygen than woodfree papers so that they are mainly used for

short-lived products. In printing papers the mechanical pulp improves


Mechanical Pulp

Pulp produced by mechanically grinding logs or wood chips. It is used

mainly for newsprint and as an ingredient of base stock for lower grade

printing papers.

Medium Density Fiberboard (MDF)

A composite panel made from wood fibers and resin and formed under

pressure and heat. MDF has a smooth surface and good machinability, and is

used for furniture, cabinetry and millwork.

Metalization Base Paper

Paper used for very high vacuum deposition. Metals are vaporized at low

temperature but very high vacuum and deposited on paper. Base paper is

light weight, no conductive particles and no pin holes.


The tendency of color to appear different under different light sources

such as fluorescent or natural sunlight.


Machine finished. Smooth paper calendered on the paper machine.


Machine glazed. Paper with a glossy finish on one side produced on the

paper machine by a Yankee cylinder.

MG Machine

A paper machine incorporating a Yankee or a MG drying cylinder in the

drying section to produce MG paper.

Micro Crystalline Cellulose Pulp

Like Ethers Pulps, these pulps are used in thickening and pharmaceutical

applications, particularly in construction of tablets and other

non-capsular pills.


The physical site where paper is manufactured; also refers to a company

that manufactures paper.

Mill Broke

Paper generated at the paper mill prior to completion of the manufacturing

process. Wet mill broke originates at the wet end of the papermaking

machine, while dry mill broke comes from the dry end of the papermaking



A thick, dense, homogeneous board, for book production, made generally

from wastepaper, on a special board making machine one sheet at a time.

Used in binding case bound books, ledgers etc. as binders’ boards.

Mineral Filler

Materials such as chalk and china clay that are added to paper in order to

change its density or improve its surface and optical properties.

Mixed Office Waste

Wastepaper generated from offices, such as letters, memos, invoices, etc.

which are collected and sorted for paper qualities. This is the major

source of post consumer fiber.

Moisture Content

The amount of moisture or water in a sheet of paper, expressed in percent.

6 to 7% is desirable.

Moisture Resistant

Paper Treated with asphalt, wax, plastic, etc. to control penetration of


Molding Pulp

Pulp, which is used for producing pulp-based or fibrous products by

pressing; example products: egg packages, trays and boxes for fruits and



A random non-uniformity in the visual density, color or gloss of a printed

area; also known as orange peel, back-trap mottle, wet-trap mottle,

pigment flocculation, striations, etc.

Mulberry Paper

A This term is given to a wide range of actual handmade and “handmade”

papers. “Handmade” meaning that is has the rough look of actual handmade

paper but it is in fact mass produced by machine. Many mulberry papers are

made from Kozo and other similar fibers. Some in fact do contain mulberry

bark and/or fibers.

It is easy to recognize Mulberry papers as they generally have distinct

fibers running through the papers. There are some mulberry papers that

have finer fibers that are not as noticeable but a large majority have the

easy to recognize large fibers. It is very pretty stuff and can be used in

all sorts of crafts applications.


Measurement of the force required, in pounds per square inch, to rupture a

sheet of kraft paper. Also known as bursting strength.

Multiply Board Machine

A machine in which a number of plies of paper can be combined together in

the wet state to produce thick paperboard..

Multiply Paper Making Process

A paper/board making process in which different layers of fibers are

deposited one over the other to form the sheet. The multiply process is

used to make the optimum use of various type of fibers available. It is

also used to make heavy basis weight papers.

Multi-stage Cooking

Chemical pulping process in which the alkalinity of the cooking liquor is

varied by charging the alkali in several stages.


Native Lignin

The lignin as it exists in the lignocellulosic complex before separation.

Neutral Detergent Fiber (NDF)

Organic matter that is not solubilized after one hour of refluxing in a

neutral detergent consisting of sodium lauryl sulfate and EDTA at pH 7.

NDF includes hemicellulose, cellulose, and lignin.


A paper manufactured mostly from mechanical pulps specifically for the

printing of newspaper. Pulp and Paper Product Council provides the

following definition for newsprint. “A general term used to describe paper

between 40 g/m2 and 57 g/m2 generally used in the publication of

newspapers. The furnish is largely mechanical wood pulp with some chemical

wood pulp.”

Newsprint – Europe

Newsprint is that quality of paper used chiefly for the publication of

newspapers and which has a basis weight of 40 – 57 grams. Other properties

correspond to the EU harmonized definition, with a brightness up to and

including 71 ISO.




Ash content


Bulky Factor


40 – 57 grams per square metre;

white or slightly coloured;

59 – 71ISO;

not exceeding 10 percent by weight;

not exceeding 200 seconds BEKK;

below 1.7;

not less than 65 percent mechanical pulp by weight.

Newsprint – North America

The definition of newsprint used by the PPPC for statistical purposes is

as follows:





Ash Content



40 – 57 grams per square metre;

white or slightly coloured;

under 100.0 microns (0.00394 inches);

less than or equal to 65 ISO;

not exceeding 8.0% by weight;

unsized or lightly sized;

greater than or equal to 2.61 PPS :m (S10)

Newsprint – Rest of the world

Uncoated paper of a kind used for the printing of newspapers, of which not

less than 65% by weight of the total fibre content consists of wood fibres

obtained by a mechanical or chemi-mechanical process, unsized or very

lightly sized, having a surface roughness Parker Print Surf (1 MPa) on

each side exceeding 2.5 micrometres (microns), weighing not less than

40g/m2 and not more than 65g/m2.


Point where two rolls on the paper machine come in contact.

Nitration Pulps

High purity pulps that are reacted with nitric acid to form a class of

chemical derivatives called cellulose nitrates. Cellulose nitrates are

used in applications ranging from solvents to smokeless (gunpowder)


Non Wood Fibers

Papermaking fibers derived from plants other than trees such as cotton,

hemp, bagasse, jute, bamboo or straws.


Fabric-like material made from long fibers, bonded together by chemical,

mechanical, heat or solvent treatment.


Oatmeal Paper

A paper such as wallpaper to which fine sawdust is added to its stock.

Odd Lot

Off standard paper. Also the term used for side rolls or sheet left after

cutting standard size/order.

Off-machine Coating

Coating of paper on a separate coating machine.

Off-machine Creping

A method whereby paper is creped in a separate operation rather than by

the paper machine’s Yankee cylinder.

Offset Paper

Also known as book paper. General description of any paper primarily

suited for offset printing. Can be coated or uncoated. Characterized by

strength, dimensional stability, lack of curl and freedom from foreign

surface material. Finish can be vellum or smooth.

Offset Paper

Also known as book paper. General description of any paper primarily

suited for offset printing. Can be coated or uncoated. Characterized by

strength, dimensional stability, lack of curl and freedom from foreign

surface material. Finish can be vellum or smooth.

Offset Printing

Also know as web offset or lithography. Offers highest degree of

precision, clarity, and quality.

Old Corrugated Container (OCC)

Brown boxes that have been used for their intended purpose, then collected

for recycling.


Abbreviation for a recovered paper grade including old magazines, catalogs

and similar materials.

On Machine Coating

Application of coating to the paper off the paper machine, or as a

separate operation to the papermaking.

One Time Carbon Base Paper

Unlike regular carbon paper which is used multiple time, one time carbon

as name suggest is used only once e.g. government form. The specification

on this paper is not as stringent as regular carbon paper.

Onionskin Paper

A lightweight, bond-type, thin and semitransparent paper used for

duplicate copies of typed matter to save filing space.


That properties of paper which minimizes the “show-through” of printing

from the backside or the next sheet. The higher the opacity the less

likely that the printing on one side will be visible from the other side.

Open End Envelope

An envelope that opens on the short dimension.

Optical Brightener

Fluorescent dyes added to paper to enhance the visual brightness; the dye

absorbs ultraviolet light and re-emits it in the visual spectrum.

Optical Brightness

Optical brighteners or fluorescent dyes are extensively used to make high,

bright blue – white papers. They absorb invisible ultraviolet light and

convert to visible light, falling into the blue to violet portion of the

spectrum, which is then reflected back to our eyes.

Optical Whitener

A dye that is added to the fiber stock or applied to the paper surface at

the size press to enhance its brightness.

Orange Peel

A type of sheet surface that looks like orange.

Organosolv Pulping

Pulping method using organic solvent, e.g. organic acid or alcohol, as

delignification/cooking chemical.

Out of Square

Paper which is trimmed improperly so the corners are not true 90 degrees.

This will result in difficulty when the presser does not have a good guide

edge to work from for accurate register.

Out Turn Sheet

A sheet of paper, taken during manufacture, serving as a reference for the

mill or client.

Oven Dry Moisture Content

The percentage loss in weight of a paper specimen when dried to constant

weight in an oven maintained at the temperature of 105 +/- 2 C.

Oxygen Bleaching

A process in which pulp is initially treated with oxygen followed by 4-5

bleaching stages.

Oxygen Delignification

A process in which oxygen gas and sodium hydroxide are used to remove

lignin from brown stock.

Ozone (O3)

A highly reactive gas with molecules made up of three oxygen atoms.

Ozone Bleaching

A process that uses ozone to whiten cellulose fibers following the Kraft

pulping and oxygen delignification processing.


Packaging Paper

A paper or paperboard used for wrapping or packing good.

Packaging Paper

A paper or paperboard used for wrapping or packing good.


A platform with a slatted bottom, used to hold and ship cartons of paper

stacked on top of each other. A standard amount of paper that fits on a

wooden pallet. In cut-size sheets, a pallet equals 40 cartons.


A homogeneous sheet formed by irregularly intervening cellulose fibers.

Paper Cut

The excruciating, often unforeseeable, and usually

invisible-to-the-naked-eye cut received when skin slides along the edge of

a piece of paper at just the wrong angle.

Paper Surface Efficiency (printing)

Measure of the printability of a sheet of paper which is dependent upon

the amount of ink the paper absorbs, the smoothness of its surface, and

the evenness of its caliper.


A heavy weight, thick, rigid and single or multi-layer sheet. What

differentiates paperboard from paper is the weight of the sheet. If

paperboard is very heavy it is called Board. Paper heavier than 150 gram

per meter square are normally called Paperboard and paperboard heavier

than 500 gram per meter square are called board.

Paper-ink Affinity

The tendency for paper and ink to attract and stay attracted to each

other. This keeps the ink on the paper and off the reader’s hands or the

next sheet. An incompatibility between ink and paper can cause printing



Invented in China by T’sai Lun some 2,000 years ago, papermaking still

follows the same basic procedures. Today wood chips are cooked with

chemicals to release cellulose fibers and dissolve lignin, then washed to

remove impurities. Most printing papers are then bleached to lighten the

color of the pulp. Pulp is mechanically and chemically treated to impart

certain desired characteristics such as strength, smoothness and sizing.

Large quantity of water is added to uniformly distribution of fibers and

additives. The resulting slurry, which is 99 to 99.5% water, is cascaded

onto the continuously moving forming fabric of the Fourdrinier paper

machine. Side-to-side shaking distributes the slurry, forming a tangled

web of fiber as the water drains off. A wire mesh roll called a dandy

roll, moves over the surface to modulate the turbulence and smooth the

topside of the paper. A felt blanket absorbs more water from the paper and

sends the sheet on through a channel of hot metal drums that dry and press

the paper at the same time to give it a more even-sided finish. At this

point the paper is fully dry and ready for off-machine processes such as

coating, embossed finishes and supercalendering.


A paper used for greeting cards, stationery, etc…which is distinctive from

regular stock in that special watermarks and embossing may be used.


The Egyptians used this aquatic plant to create a writing sheet by peeling

apart the plant’s tissue-thin layers and stacking them in overlapping,

crosshatched pieces to form a sheet. Despite giving us the word “paper,”

papyrus is not a true paper.


A sheet of writing material made from the skins of goats or other animals.

Vegetable or imitation parchment is made to resemble animal parchment by

passing a sheet of unsized, pure fiber paper through a bath of sulfuric

acid and then washing it very thoroughly and drying. The acid gelatinizes

the surface fibers and the dried surface is grease-proof, has a high wet

strength and is very resistant to disintegration by water and many



Method of treating a paper sheet with sulfuric acid to make it



Airborne solid impurities such as those present in gaseous emissions

(sodium sulfate, lime, calcium carbonate, soot).

Peel Strength

The amount of normal force required to delaminate a multiply paper.

Strength measured by TAPPI useful method UM808 or other similar methods.

Perfecting Press

A printing press that simultaneously prints both sides of a sheet of paper

as it passes through the press. On other presses, printing both sides

means running the sheet through the press to print one side, allowing the

ink to dry, turning the paper over, and then running the sheet through the

press again to print the other side.


The degree to which paper resists deterioration over time.

Permanent Paper

A paper that can resist large chemical and physical changes over and

extended time (several hundred years). This paper is generally acid-free

with alkaline reserve and a reasonably high initial strength.

Permanganate Number (K Number)

Chemical test performed on pulp to determine the degree of



Degree to which a fluid (gas or liquid) permeates or penetrate a porous

substance such as paper or fabric.

Pernicious Contraries

Any material present in waste paper that is difficult to see or detect and

which might be detrimental to the paper being manufactured from the

wastepaper or which might either damage paper making equipment or render

repulping difficult

Peroxide Bleaching or Hydrogen Peroxide Bleaching

Method of bleaching pulp with hydrogen peroxide (H2O2) to remove lignin;

reduces or avoids the need for chlorine dioxide in final bleaching.

pH (Hydrogen Ion Concentration)

A measure of the acidity (or alkalinity) of a solution. Range from 0-14

with 7 being neutral, less than 7 being acid; higher than 7 being



A material which undergoes destruction of its chemical structure when

exposed to light. Typically, the materials become brittle with time and

fragment into small pieces or powder.

Photographic Paper

The base paper used for the production of photographic papers is a

dimensionally stable, chemically neutral chemical pulp paper with wet

strength properties, that must be free from contaminants. Today papers are

coated on both sides with a thin polyethylene film. The cooking prevents

chemicals and water entering the paper during development. This also

permits shorter rinsing and drying cycles.

Pick Out

A problem on press caused by unevenly sealed paper, or paper with low

bonding strength. The ink “picks” off weak areas of the paper, lifting

coating from a coated stock or lifting fibers from an uncoated stock, and

transferring them to the printing blanket.

These fibers will eventually be transferred back onto the sheets

being printed, causing inking and surface inconsistencies.

Pick Resistance

The ability of paper fibers to hold together during the printing process.

Pick Up Roll

Roll, which lifts the wet paper or paperboard off the wire to transfer to


Picking (Papermaking)

To transfer the wet sheet from wire part to press part. If the sheet moves

unsupported is called “poor man pick up”. If a solid/suction roll is used

to lick/pick the sheet, it is referred as closed transfer.

Picking (Printing)

The problem of ink picking off paper fibers during printing. This may be

an indication of a paper with low bonding strength or the use of an ink

with too much tack for the paper it is printed on.


An ingredient added to pulp to increase the brightness and opacity of

white paper or dye the pulp to create a colored sheet. Pigments have very

high lightfastness and bleedfastness.


Coating of paper with a chemical agent (pigment) to reduce surface

porosity and increase opacity.

Pin Holes

Imperfections in paper which appear as minute holes upon looking through

the sheet. They originate from foreign particles, which are pressed

through the sheet.


Defect in reels, consisting of ridges running around the circumference,

due to moisture take-up by the surface layers or uneven binding or hard

and soft spots.


Resinous material present in wood (mainly softwood) that carry over into

the pulping and papermaking system to form insoluble deposits.

Playing Card Stock

A stiff board, usually made by pasting sheets of fourdrinier paper, and

given a coating which will take a high polish.


The separate webs, which make up the sheet formed on a multi-cylinder

machine. Each cylinder adds one web or ply, which is pressed to the other,

the plies adhering firmly upon drying.


A unit of paper or paperboard thickness measuring one-thousandth of an


Poly Extrusion Paper

Paper used for plastic extrusion. Hot melted plastic is applied at the

paper surface, so the base paper should be able to withstand heat.


A chemical term for several classes of organic or carbon containing

chemicals where a monomer or single chemical molecule is connected to

itself in repeating units to form a chemical “chain.” An example of a

polymer is cellulose, a repeating chain of glucose (sugar). Other examples

are polyesters, nylons, viscose, lyocell, polyolefins and polystyrenes.


The property of paper that allows the permeation of air, an important

factor in ink penetration.

Postcard Board

Postcard board is either slightly mechanical or woodfree and calendered.

Post-Consumer Waste Paper

Waste paper materials recovered after being used by consumers.

Poster Paper

Poster paper is a highly mechanical, highly filled, mostly coloured paper

that has been made weather resistant by sizing.

Poster Paper

Poster paper is a highly mechanical, highly filled, mostly coloured paper

that has been made weather resistant by sizing.

Precision Sheeting

Converting rolls of paper into finished sheet sizes in a single operation.

Pre-Consumer Waste Paper

Waste material from manufacturing operations – dry mill and printer

factory waste, newsstand returns- that has not reached its end-user. This

is highly desirable waste because it normally contains fewer contaminants

and is easier to process.


A combination of two or more rolls used to press out water from wet paper

web. Following are some of the types of the press.

1. Plain Press or Solid Press

This is the simplest and the oldest type of press which is now a

days rarely used except on very slow speed machine. The solid press

consists of two solid rolls covered with rubber and or granite. The top

roll is somewhat offset for the squeezed out water to flow by gravity.

2. Suction Press

In this type of press, one roll is drilled and shell of the drilled

roll rotates over a suction box. The squeezed water is sucked out through

the felt.

3. Grooved Press

In this type of press, one roll is grooved. The squeezed water is

hold in the groves and removed by doctoring or sucking out on the return

run of the roll.

4. Smoothing Press

A plain roll press just before the dryer section start, used to

smoothen the paper surface.

Press Part or Press Section

The section of the paper machine which contains press (es). It is usually

located between wire part and dryer part.

Pressure Sensitive Coated Paper

Paper coated with a self-adhesive material which in dry form (solvent

free) is permanently tacky at room temperature. A bond with the receiving

surface may be formed by the application of pressure (e.g. by the finger

or hand). A permanent adhesive is characterized by relatively high

ultimate adhesion and a removable adhesive by low ultimate adhesion. Until

the time of application, the adhesive surface should be covered by a

suitable release coated paper.

Pressurized Groundwood Pulp (PGW)

Mechanical pulp produced by treating logs with steam before defibration

against a grindstone under externally applied pressure.


The overall performance of the paper on press.


The transfer of ink onto paper or other materials to reproduce words and


Publishing Paper

On-machine coated printing paper. Suitable for color printing or toning

with low grid number or single color printing. Our products in this

category includes: Wood-free printing and writing paper, Ivory wood-free

printing and writing paper.


A suspension of cellulose fibers in water.

Pulp Board

Also known as Printers’ Board, this grade is made from a single web of

pulp on a paper making machine, and is produced in various substances.

Used for index cards and other general products, these boards may be white

or colored.


Unit for defibrating (slushing) pulps and paper machine broke, usually at

the wet end of the paper machine.

Puncture Resistance

The puncture resistance of combined board indicates the ability of the

finished container to withstand external and internal point pressure

forces and to protect the product during rough handling.




The term “rag” is often used interchangeably with “cotton fiber content”

and harkens to a period of time when paper was actually made using cotton

rags which were cleaned and then broken down into fibers which were then

used to manufacture paper. In a sense it could be stated that the fine

paper business has been engaged in recycling materials for production

since its very beginning. Today paper is no longer made from rags and the

term “rag” is falling in disfavor by the industry in lieu of the phrase

“cotton fiber content”.

Rag Paper

Today rag paper is mostly made from vegetable fibers consisting of

cellulose, such as cotton, linen, hemp and ramie. Rags are the most

precious raw material for the papermaker. Rag papers and rag-containing

papers with admixtures of chemical pulp are used for banknotes, deeds,

documents, books of account, maps and copperplate engravings and as

elegant writing papers. They are also used for special technical


Rag Pulp

Papermaking pulp made from textile waste, cotton, hemp or flax.

Ragger Rope

A rope used to remove contraries from the pulper.


That combination of properties such as stiffness, density etc. which is

responsible for noise when the sheet is shaken or flexed.


500 Sheets of paper.

Recovered Paper

Paper recovered for recycling into new paper products. Recovered paper can

be collected from industrial sources (scraps, transport packaging, unsold

newspapers…) or from household collections (old newspapers and

magazines, household packaging).

Recovered Paper Grades

Recovered paper sorted by types in order to be recycled by paper mills.

Specific grades are used by paper mills, in order to produce different

types of paper and boards.

Recovery Boiler

Boiler used to burn black liquor from chemical pulping for recovery of

inorganic chemicals as well as for energy production.

Recovery Rate (Chemical)

Amount of chemical recovered in chemical recovery process as a percentage

of chemical used in pulping. Chemical loss is compensated my make up


Recovery Rate (Paper)

Amount of paper recovered as a percentage of amount of paper consumed.

Rectifier Roll or Holey Roll

Hollow perforated roll in headbox used for even out the flow of fibers and

prevent settling of fibers in headbox by providing gentle agitation.

Recycled Fiber

Fiber obtained from recovered paper; also secondary fiber (cf. virgin


Recycled Fiber Pulp

Pulp produced from recovered paper to be used in papermaking.


Use of recovered waste paper and board by paper mills to produce paper and



General name of various perennial plants; e.g. common reed, reed canary

grass, giant reed; potential feedstock for pulping and papermaking.


A continuous sheet of paper wound on a core.


An equipment used to give mechanical treatment to the fibers.

Refiner Mechanical Pulp (RMP)

Mechanical pulp produced by passing wood chips between the plates of a


Refiner Sawdust Pulp

Mechanical pulp produced from sawmill dust.


Mechanical treatment of fibers to enhance bonding.


Ability of paper or board to reflect light; a measure of gloss.


A measure of how much a sheet of paper deflects the light that hits it.

The more light a sheet deflects, the greater its refractiveness, allowing

a printed image to be more brilliant and detailed.


Putting two or more images together so that they are exactly aligned and

the resulting image is sharp.


Method for strengthening paper with an insert or surface layer of glass or

other synthetic fiber or metal.

Reinforcement Pulp

Softwood chemical pulp added to give paper greater strength and to improve

runnability on the paper machine or printing press.


Material removed and discarded during the cleaning and screening of


Release Paper

Release paper is used to prevent the sticking of glue, paste or other

adhesive substances. Coating paper with silicone yields papers with a

surface that prevents adhesion of most substances. Application: cover

material for self-adhesive papers or films, e.g. in label production.


A method for printing ink on paper, using type or images that rise above

the surface of the printing plate. Ink sits on top of these raised

surfaces, and as the paper is pressed onto them it picks up ink.

Letterpress, flexography, and rubber stamps all use relief plates. In

letterpress, intense pressure can cause images to be slightly debossed or

depressed below the surface of the paper.

Residual Fibers

Fibers derived from sawmills scraps, plywood plants and other timber

management activities.


A paper’s ability to return to its original form after being stretched,

bent or compressed during the printing and bindery process.


The amount of filler or other material which remain in the finished paper

expressed as a percentage that added to the furnish before sheet

formation. Retention can occur by various mechanisms. The simplest of

these is mechanical sieving by the forming fabric. Once a fiber mat begins

to form, the mat itself usually can act as a much more effective and finer

sieve than the forming fabric. But even then, particles less than about 10

micrometers in size are not effectively retained by sieving. Rather,

retention of fine particles requires the action of colloidal forces,

including polymeric bridging or a charged patch mechanism. Retention aid

chemicals can be effective either by attaching fine particles to fiber

fines or fibers or by agglomerating them so that they can be sieved more


Retention Aid

Chemical additives, especially high molecular weight copolymers of

acrylamide, designed to increase the retention efficiency of fine

materials during paper formation.


Equipment which slits and rewinds paper webs into smaller rolls.

Rice Paper

A common misnomer applied to lightweight Oriental papers. Rice alone

cannot produce a sheet of paper. Rice or wheat straw is used occasionally

mixed with other fibers in paper making. The name may be derived from the

rice size (starch) once used in Japanese papermaking


Roll defect where there are raised bands or rings of material around the

circumference of the roll.

Ring Crush Test (RCT)

A test method for measuring the edgewise crush resistance by forming the

paper into a cylinder and applying a crushing force to the edge. (TAPPI


Rising Film Evaporator

A type of tubular heat exchanger used for concentrating a solution

consisting of a non-volatile solute and a volatile solvent; solution flows

upward on the heat exchange surface; vaporization ‘ of the volatile

solvent reduces the density of the mixture and causes the vapour-liquid

mixture to rise; commonly used in pulp mills but less common in new


Rod Coater

In rod coater, the rod is the metering device, which controls how much wet

coating is allowed to leave the coating station. Typically thirty times

more will be applied compared to the actual target coat weight.

Roe Number

Measure of the amount of chlorine required for bleaching pulp.

Roll Coating

A process in which the coating is applied by roll and subsequently

smoothed by means of reverse rolls contacting the freshly coated surface.

Roofing Paper

Board that is impregnated with tar, bitumen and/or natural asphalt.


Rosin, a natural resin from pine trees in combination with alum, is used

for internal sizing of paper in acidic paper making. The chemical formula

of rosin is C19H29COOH.

Rosin Size

Partially or completely saponified (neutralized) rosin. The chemical

formula of rosin is C19H29CONa.


The opposite of letterpress printing in that the design areas are recessed

into the plate instead of being a relief. It is web-fed and prints thin,

quick drying ink to produce multiple colors. Used in corrugated packaging.


Heavily textured surfaces produced by minimal pressing after sheet


Rough Finish

Paper having an exceptionally rough or coarse textured surface.


The ease with which a paper moves through a printing press or converting

machine. This is primarily determined by the paper’s strength, tear

resistance, dimensional stability, bonding strength and water resistance



The term is used interchangeably with the word “bag” applied to a

non-rigid container made from paper or other flexible material.

Safety Paper

Papers with a special protection against abusive imitation. The safeguards

used during the production of the paper – some of them chemicals are


Salt Cake

Or sodium sulfate added to the black liquor to compensate for the soda


Sanitary Papers

The group of sanitary papers includes cellulose wadding, tissue and crepe

paper, made from waste paper and/or chemical pulp – also with admixtures

of mechanical pulp. As a consequence of the importance of tissue today,

this name is now used internationally as a collective term for sanitary

papers. These grades are used to make toilet paper and numerous other

sanitary products such as handkerchiefs, kitchen wipes, towels and

cosmetic tissues.

Sanitary Tissue Paper

Tissue is a sanitary paper made from chemical or waste paper pulp,

sometimes with the admixture of mechanical pulp. It has a closed structure

and is only slightly creped. It is so thin that it is hardly used in a

single layer. Depending on the requirements the number of layers is

multiplied. Creping is made at a dryness content of more than 90 %. The

dry creping (unlike with sanitary crepe papers) and the low grammage of a

single tissue layer result in a high softness of the tissue products. For

consumer products it is normally combined in two or more layers. The

flexible and highly absorbent product [is mainly produced from chemical

pulp and/or DIP – sometimes also with admixture of groundwood pulp] can

also be provided with wet strength. Applications: facial tissues, paper

handkerchiefs, napkins, kitchen rolls, paper towels, toilet paper.

Sap Wood

The fluid part of the tree that moves up from the roots through the outer

portion of the trunk and branches and contributes to its growth.

Satin Finish

A smooth, satin-like, semi-glossy finish of paper or Bristol.


Equipment used to reclaim fibers from white water.

Saw Dust

Fine wood particles created when sawing wood; used as biofuel, pulping raw

material, panel board production, animal litter etc.


To impress or indent a mark with a string or rule in the paper to make

folding easier.


To impress or indent a mark with a string or rule in the paper to make

folding easier.

Scott Bond

An internal bond test that measures the force needed to separate fibers

within a single ply by TAPPI method.


Device used to remove large solids particles such as fiber bundles and

flakes from stock. In good old days screen used to be open type and could

deal with thin stock only. Modern screen are closed (pressurized) and can

handle low, medium and even high consistency stock. Perforation in screen

basket can be circular, counter shrink or slotted. The screen used just

before headbox not only remove large particles but also align fibers in

the direction of stock flow.

Scuff Resistance

Linerboard’s ability to resist abrasion in the shipping environment may

affect external appearance.


The means of joining the two ends of the fabric together.

Secondary Fibers

Fibers recovered from waste paper and utilized in making paper or


Security paper

Paper which includes identification features such as metallic strips and

watermarks to assist in detecting fraud and to prevent counterfeiting.

Self Adhesive paper

Used essentially for labeling purposes, this grade has a self-adhesive

coating on one side and a surface suitable for printing on the other. The

adhesive is protected by a laminate which enables the sheet to be fed

through printers or printing machines, the laminate subsequently being

stripped when the label is applied

Self Contained paper

A self imaging carbonless paper that does not need the use of any other

carbonless stock to make an image appear. When pressure is applied, it

causes the chemicals on the front of the sheet to create an image. This

paper is used in ribbonless impact printers.

Semi-Alkaline Pulp (SAP)

Sulfite pulp cooked at slightly alkaline pH (normal sulfite pulp is cooked

at acid pH). SAP is superior in strength to normal sulfite pulp. Used

mainly in printing papers.

Semi-Bleached Pulp

Pulp bleached to a brightness somewhere between that of unbleached and

fully bleached pulp.

Semi-chemical Pulp

Pulp produced by chemical treatment followed by mechanical treatment.


A number of units or bales picked up at the same time by crane or truck.


The color depth and hue in comparison to papers that are the same color;

also used to describe the color achieved by adding dye to pulp slurry.

There is a wide shade variety in white papers, as well as in colored


Shadow Mark

A defect in paper appearance which looks like the drilling pattern in a

suction roll. It is due to opacity effects caused by areas of vacuum and

pressure as the wet web passes over a suction roll.


The device to shake the wire at the breast roll end from side to side.

Sheeter or Cutter

Machine for cutting the paper web into sheets.

Sheffield Porosity

A test used to measure the smoothness of paper by measuring the rate of

air flow over the surface of the sheet. The lower the number, the smoother

the sheet.


Small bundles of fibers that have not been separated completely during


Show Through

The degree to which a printed film is visible through paper due to the low

opacity of the paper. The undesirable condition in which the printing on

the reverse side of a sheet can be seen through the sheet under normal

lighting conditions. The more opaque a sheet, the less the show-through.


Water jets or sprays used throughout the pulp and paper mills to wash wire

mesh screen, forming wires, press felts, pulp mat, to dilute pulp etc.

High Pressure Showers A shower consisting of numerous needle jet

nozzles along its length at a pressure of up to 300 psi.

Lubrication Showers A shower consisting of fan nozzles along its

length to provide full coverage of the felts surface with water. This

lubricates the felt as it passes over the suction boxes.

Oscillation Showers The movement from side to side of the shower bar

to ensure full coverage of the felts surface by the water jets.

Side Run

(1) A narrow reel removed from a web during processing, the width of which

is less than the size ordered, but is large enough to permit its use for

purposes other than re-pulping.

(2) An additional part of an order placed in order to better utilize

the maximum trimmed machine width of the making machine.

Silicon Treated Paper

A strong paper with a glazed finish that is treated with silicones on one

side. This produces a release quality that is necessary for the liners

used for pressure sensitive paper.

Single Faced Corrugated Board

Corrugated fiberboard consisting of two layers, one of fluted paper and

one of facing.

Size Press

Section of paper machine where surface treatments are applied to the sheet

of paper to give it special qualities. Normally comprised of a pair of

rolls towards the end of the dryer train between which the dry or

partially dry web is passed, and into the nip of which a liquid, usually

starch, is applied to impart strength to the sheet. Sometimes a chemical

may be added to produce a water-resistant sheet

Sized Paper

Sizing reduces the water absorbency of the paper and thus creates the

condition for the writability with ink. Sized paper is also used for many

other purposes (printing, coating, gluing, etc.), and the sizing agents

must fulfil a wide range of tasks. For instance, they control the water

absorbency and increase the ability to retain water and ink (pick



The treatment of paper which gives it resistance to the penetration of

liquids (particularly water) or vapors. Sizing improves ink holdout.


Outlet from the head box through which the pulp suspension is fed into the

forming section.

Slide Resistance

The ability of containers to resist sliding in unit loads can be predicted

for the coefficient of friction of the combined board. A low coefficient

demonstrates containers slipping from the load.

Slime Holes

A hole in paper, characterized by brownish translucent material around the

edges. Caused by a lump of slime which has formed in stock system from the

growth microorganisms, then becoming detached and flowing onto the paper

machine wire with the fiber to form a non-fibrous area.


Fungus or other bacteriological growth. If not controlled in papermaking

system, may cause process and quality problems.


Rotary knife used to slit or trim a paper web into specified width.


Dividing a web of paper in the lengthwise direction into two or more

narrower webs.


Measure of pulp drainage. Has an inverse relationship to freeness.


The waste material left over after pulping and deinking. Although some

sludge is produced in the virgin papermaking process, far more is produced

in the deinking (recycling) process. Recycling breaks recovered paper down

into fibers, which are sent to the paper machine for new production, and

other materials, which drop into the sludge. These “other materials”

include clay coatings, fillers from the previous paper, paper clips and

staples, fibers too short to be made into paper, ink if it wasn’t skimmed

off in the deinking process, and any “junk” that crept into the wastepaper



Inorganic chemicals obtained in molten form from the recovery furnace.

Smooth Finish

A highly calendered or machine-finished sheet.


The surface uniformity of paper. Sheets that are flat and even provide

better ink dot formation and sharper images.

Soda Pulping

An alkaline pulping process that uses a simple, sulfur- free sodium

hydroxide as cooking liquor.

Soft Cook

Over-cooked pulp.

Soft Nip Calendar

A machine device consisting of two or more pairs of steel and composition

rolls; it is designed to achieve much of the quality of a Supercalender,

with much of the production advantage of being on machine, but without the

severe operating difficulties of an on-machine Supercalender.


Woods obtained from coniferous trees. Generally grown in cold climates.

Softwood grows slower than hardwood but have longer fibers compared to


Solid Fiberboard

Collective term for all solid board grades.

Soy Inks

Inks containing soybean oil.

Specialty Paper

The group of specialty papers comprises numerous paper grades, each

characterized by particular properties. These properties often require

special raw materials.

Specialty Pulp

Chemical pulps used for purposes other than ordinary papermaking (e.g. in

textile production)

Specific Energy (Refining)

Energy applied per unit weight on oven dry basis (KWH/MT) during refining.

Specific Surface (Fiber)

Fiber surface area per unit weight (OD basis)

Specific Surface Load (Refining)

Specific edge load divided by refiner bar width factor (Watt-Sec/m2)


A small defect of foreign substance with contrasting appearance to the

surrounding paper.

Spent Liquor

Liquor recovered from cooked pulp.

Spinning Paper

Paper with a particularly high tensile strength in the machine direction;

suitable for being spun into yarn or string.


Formed by overlapping webs and joining with a strip of double-faced

adhesive tape. Used for lighter-weight grades of paper.

Spread Coating

A method of coating a web of paper by means of a vertical plate

restraining a pond of viscous coating material, for example resins,

plastics or adhesives, which is drawn through an adjustable gap between

the plate and the paper by the forward movement of the web over a

horizontal support

Stamp Paper

Paper used for printing postal stamp. Paper should have good printability,

high strength, good glueability, permanence and high dimensional



The wooden hammers used in a watermill to pulp rags in order to separate

the fibers.

Standard Test Conditions

Atmospheric conditions of temperature and humidity in which laboratories

agree to conduct tests, eliminating those variables in comparing results.


A natural product from corn, potatoes, tapioca, etc., and used for dry

strength. Cationic starch is added at the paper machine wet end.

Starch is a free flowing white powder. Typically, starch used in the

paper industry is extracted from maize kernels, wheat or potatoes; in rare

cases, tapioca or rice can be the source. Starches from the different

plants each have a characteristic granule size and shape.

Potato starch is often referred to as farina, and maize starch is

sometimes called corn. Native starch is sometimes called pearl starch.

Steam Finishing or Steam Calendering

A way of treating paper before calendering to improve its density and

surface smoothness


Wood chips are often treated with steam prior to pulping; used in

thermo-mechanical pulping. Also injection of steam in direct or indirect

cooking digester for chip packing and or cooking.


A sheet of plastic, paper, or other material with letters or an image cut

out of it. When placed on a surface and inked, it reproduces the cut-away

images onto the material behind it.


Sticky materials in recycled papermaking pulp, often resulting from

pressure-sensitive labels.


The ability of paper or paperboard to resist an applied bending force and

to support its own weight while being handled. A sheet that is too limp

can cause feeding and transport problems in copiers and printers. An

adequate degree of stiffness is important to avoid distortion of the paper

due to the pull of ink during offset printing. Stiffness is critical to

many converting operations for forms and envelope grades.


A term used to define pulp after mechanical (refining or beating) and /or

chemical treatment (sizing, loading, dying etc.) in the paper making

process. A pulp ready to make paper.

Stock Preparation

Collective term for all treatment necessary for the preparation of the

stock before it reaches the paper machine.

Straw Pulp

Pulp that is made from the straw of grains such as rice straw. It is

cooked by soda process.


Board made from partially cooked straw, bagasse or grass or a mixture of



The maximum tensile strain developed in paper before rupture. The stretch

or percentage elongation is expressed as a percentage.


The penetration of ink through paper.


The base material on which a substance (such as ink, adhesive, coating) is


Suction Box (Vacuum Box)

Device that removes water from the paper machine by a suction action

located beneath the wire at the wet end.

Suede Paper

Paper that has a velour finish.

Sulfate Pulping

Alkaline process of cooking pulp.

Sulfite Pulping

Acid process of cooking pulp

Super Art Paper

Highest grade of art paper with double or triple coating. Coat weight of

25g/m2 per side, with gloss level over 80%, surface feels smooth and

shiny, superb printing quality, suitable for high-quality picture books,

product catalogues, and refined printing products..


A stack of alternating steel and fiber-covered rolls at the end of the

paper machine which is used to increase a sheet’s gloss and smoothness.


Treatment of paper on an off-machine supercalender to improve smoothness

and gloss.

Surface Roughness

For coated boards, Parker Print Surf (PPS) roughness tester is used where

the test result is expressed as an average of the surface profiles in

micrometers ( m ) low results show smooth surface while high results

indicate poor surface.

For coated board, Bendtsen method readings given as total leakage of air

in ml/min. Smoother surface has lower readings

Surface Smoothness

The smoothness of the linerboard surface may affect printing quality

because slight depressions may not receive complete ink coverage. Surface

smoothness may also affect the coefficient of friction, gloss and coating


Surface Strength Test

The method consists of printing a strip of paper in a print tester at an

accelerating rate. The method is preferable to Wax Pick.


Paper that has been treated with starch or other sizing material at the

size press of the paper machine. This term is used interchangeably with

the term “tub-sized”, although tub-size more properly refers to surface

sizing applied as a separate operation where the paper is immersed in a

tub of sizing (starch or glue), after which it passes between squeeze

rolls and is air dried.

Sustainable Forest Management

Managing a forest in a way that enhances its ecosystem while providing

environmental, economic, social and cultural opportunities for present and

future generations.


An increase in volume of fiber due to the absorption of liquid.

Synthetic Fiber Paper

Papers made from synthetic fibers such as polyamide and polyester, from

viscose staple fiber or sometimes also with fillers. The fibers are mainly

held together by binders. The durable synthetic fiber papers are used for

maps and highly important documents such as driving licenses or vehicle

registration books.



Abbreviation indicating that the paper has been guillotine trimmed on all

four sides. Literal translation: trimmed four sides.

Table Roll

The small diameter rolls used to support the wire.

Tack or Stickiness

Tack is a critical property of the ink used in lithography. Because the

ink sits on a flat surface, it needs internal cohesion; in other words, it

needs to stick to itself so that it doesn’t run all over the plate.

However, too much tack can cause it to pull the paper apart. When printing

two or more ink colors in line, the ink tack and sequence must be adjusted

in order for the inks to adhere to each other as well as to the paper.

Tag Paper

A heavy utility grade of paper used to print tags, such as the store tags

on clothing. Tag paper must be strong and durable, yet have good affinity

for printing inks.


Mineral used in papermaking as a filler and coating pigment.

Tea Bag Paper

Used to pack tea leaves. Paper should not have any impurities. It should

have high liquid permeability and should withstand boiling water.

Tear Index

Tear index = tearing resistance/basis weight.

Tear Resistance

The mean force required to continue the tearing of paper from an initial

cut under standardized conditions.

Tear Strength

A measure of how likely a paper will continue to tear once started. Tear

strength will differ with and against the grain.

Technical Paper

Variety of medium-grammage papers used in different industrial purposes.

Tensile Energy Absorption (TEA)

It is the work done when a paper specimen is stressed to rupture in

tension under prescribed conditions as measured by the integral of tensile

strength over the range of tensile strain from 0 to maximum.

Tensile Index

Tensile index = tensile strength (N/m) /basis weight (g/m2).

Tensile Strength

A measure of how likely a paper is to break when pulled at opposite ends.

This is very important when running through high-speed web presses.

Terms of Sale

The point at which sellers have fulfilled their obligations so the goods

in a legal sense could be said to have been delivered to the buyer. They

are shorthand expressions that set out the rights and obligations of each

party when it comes to transporting the goods. Following, are the thirteen

terms of sale in international trade as Terms of Sale reflected in the

recent amendment to the International chamber of Commerce Terms of Trade (INCOTERMS),

effective July 1990: exw, fca, fas, fob, cfr, cif, cpt, cip, daf, des, deq,

ddu and ddp.

Terms of Sale – CFR (Cost and Freight) (…Named Port of

Destination) A Term of Sale where the seller pays the costs and freight

necessary to bring the goods to the named port of destination, Terms of

Sale but the risk of loss of or damage to the goods, as (continued) well

as any additional costs due to events occurring after the time the goods

have been delivered on board the vessel, is transferred from the seller to

the buyer when the goods pass the ship’s rail in the port of shipment. The

CFR term requires the seller to clear the goods for export.

Terms of Sale – CIF (Cost, Insurance and Freight) (…Named Place of

Destination) A Term of Sale where the seller has the same obligations as

under the CFR but also has to procure marine insurance against the buyer’s

risk of loss or damage to the goods during the carriage. The seller

contracts for insurance and pays the insurance premium. The CIF term

requires the seller to clear the goods for export.

Terms of Sale – CIP (Carriage and Insurance Paid To) (…Named Place

of Destination) A Term of Sale which means the seller has the same

obligations as under CPT, but with the addition that the seller has to

procure cargo insurance against the buyer’s risk of loss of or damage to

the goods during the carriage. The seller contracts for insurance and pays

the insurance premium. The buyer should note that under the CIP term the

seller is required to obtain insurance only on minimum coverage. The CIP

term requires the seller to clear the goods for export.

Terms of Sale – CPT (Carriage Paid To) (…Named Place of

Destination) A Term of Sale which means the seller pays the freight for

the carriage of the goods to the named destination. The risk of loss of or

damage to the goods, as well as any additional costs due to events

occurring after the time the goods have been delivered to the carrier, is

transferred from the seller to the buyer when the goods have been

delivered into the custody of the carrier. If subsequent carriers are used

for the carriage to the agreed upon destination, the risk passes when the

goods have been delivered to the first carrier. The CPT term requires the

seller to clear the goods for export.

Terms of Sale – DAF (Delivered At Frontier) (…Named Place) A Term

of Sale which means the sellers fulfill their obligation to deliver when

the goods have been made available, cleared for export, at the named point

and placed at the frontier, but before the customs Terms of Sale border of

the adjoining country. (continued)

Terms of Sale – DDP (Delivered Duty paid) (…Named Port of

Destination) Delivered Duty Paid means that the seller fulfills his

obligation to deliver when the goods have been made available at the named

place in the country of importation. The seller has to bear the risks and

costs, including duties, taxes and other charges of delivering the goods

thereto, clear for importation. While the EXW term represents the minimum

obligation for the seller, DDP represents the maximum.

Terms of Sale – DDU (Delivered Duty Unpaid) (…Named Port of

Destination) A Term of Sale where the seller fulfills his obligation to

deliver when the goods have been made available at the named place in the

country of importation. The seller has to bear the costs and risks

involved in bringing the goods thereto (excluding duties, taxes and other

official charges payable upon importation) as well as the costs and risks

of carrying out customs formalities. The buyer has to pay any additional

costs and to bear any risks caused by failure to clear the goods for in


Terms of Sale – DEQ (Delivered Ex Quay, [Duty Paid]) (…Named Port

of Destination) A Term of Sale which means the DDU term has been fulfilled

when the goods have been available to the buyer on the quay (wharf) at the

named port of destination, cleared for importation. The seller has to bear

all risks and costs including duties, taxes and other charges of

delivering the goods thereto.

Terms of Sale – DES (Delivered Ex Ship) (…Named Port of

Destination) A Term of Sale where the seller fulfills his/her obligation

to deliver when the goods have been made available to the buyer on board

the ship, not cleared for import at the named port of destination. The

seller has to bear all the costs and risks involved in bringing the goods

to the named port destination.

Terms of Sale – EXW (Ex Works) (…Named Place) A Term of Sale which

means that the seller fulfills the obligation to deliver when he or she

has made the goods available at his/her premises (i.e., works, factory,

warehouse, etc.) to the buyer. In particular, the seller is not

responsible for loading the goods in the vehicle provided by the buyer or

for clearing the goods for export, unless otherwise agreed. The buyer

bears all costs and risks involved in taking the goods from the seller’s

premises to the desired destination. This term thus represents the minimum

obligation for the seller.

Terms of Sale – FAS (Free Alongside Ship) (…Named Port of

Shipment) A Term of Sale which means the seller fulfills his obligation to

deliver when the goods have been placed alongside the vessel on the quay

or in lighters at the named port of shipment. This means that the buyer

has to bear all costs and risks of loss of or damage to the goods from

that moment.

Terms of Sale – FCA (Free Carrier) (… Named Place) A Term of Sale

which means the seller fulfills their obligation when he or she has handed

over the goods, cleared for export, into the charge of the carrier named

by the buyer at the named place or point. If no precise point is indicated

by the buyer, the seller may choose, within the place or range stipulated,

where the carrier should take the goods into their charge.

Terms of Sale – FOB (Free On Board) (…Named Port of Shipment) An

International Term of Sale that means the seller fulfills his or her

obligation to deliver when the goods have passed over the ship’s rail at

the named port of shipment. This means that the buyer has to bear all

costs and risks to loss of or damage to the goods from that point. The FOB

term requires the seller to clear the goods for export.


Mainly produced from waste paper used as even facing for corrugated board

or as liner of solid board. They are often produced as duplex (two-layer)

paper. The grammage is higher than 125 gsm.

Text Paper

Text papers are defined as fine, high quality uncoated papers. Typically,

they are made in various colors, with numerous textures and a variety of

surface finishes. Text papers are made from high-grade bleached wood pulp,

cotton fibers, or tree-free pulp such as bamboo. Recycled sheets include

high quality recycled waste paper and post-consumer waste pulp, in

addition to bleached wood pulp, tree-free pulp or cotton fibers.

Thermal Paper

Any paper with a heat-sensitive coating on which an image can be produced

by the application of heat.

Thermal Transfer Printing

Printing whereby a design image is first printed on heat transfer paper

using inks with sublimable dispersed dyes.

Thermo Mechanical Pulping (TMP)

Mechanical pulp made by steaming wood chips under pressure prior to and

during refining, producing a higher yield and stronger pulp than regular

stone groundwood or regular refiner wood pulp.

Thin Paper

Includes carbonizing, cigarette, bible, air mail and similar papers.


A practice in which certain trees are removed from a dense stand to allow

the remaining trees adequate sunlight, nutrients and moisture to grow at

an even rate.


To vary a color by adding white. Also, a very light or delicate variation

of a color.


A low weights and thin sheet. Normally a paper sheet weighing less than 40

gram per meter square is called tissue.

At Home products: Also known as Consumer Products, these are the

tissue products you purchase in the grocery store and convenience store

for use in your home and include toilet paper and facial tissue, napkins

and paper towels, and other special sanitary papers.

Away from Home products: Also known as Commercial & Industrial

Tissue, these are the products that serve markets such as hospitals,

restaurants, businesses, institutions, and janitorial supply firms.

Specialty: These types of tissue papers are often high end,

decorative papers that are glazed, unglazed, or creped, and include

wrapping tissue for gifts and dry cleaning, as well as crepe paper for


Facial tissue: The class of soft, absorbent papers in the sanitary

tissue group. Originally used for removal of creams, oil, and so on, from

the skin, it is now used in large volume for packaged facial tissue,

toilet paper, paper napkins, professional towels, industrial wipes, and

for hospital items. Most facial tissue is made of bleached sulfite or

sulfate pulp, sometimes mixed with bleached and mechanical pulp, on a

single-cylinder or Fourdrinier machine. Desirable characteristics are

softness, strength, and freedom from lint.

Titanium Dioxide

An opaque and expensive compound used as a white pigment and opacifier in

papermaking. Elemental titanium is a lustrous, lightweight, white metal

with exceptional strength.


Permissible degree of variation from a pre-set standard.

Ton on Tonne

Metric ton or Metric Tonne is equal to 1000 Kgs. or 2240 lbs. English tons

are as defined. Long Ton = 2240 lbs is similar to metric ton. Standard

English ton is 2200 lbs. Short ton is 2000 lbs.

Top Side

Side of the paper opposite to the wire side.

Total Alkali

NaOH + Na2S + Na2CO3 + 0.5*Na2SO3 all expressed as Na2O in alkaline

pulping liquor.

Totally Chlorine Free (TCF)

Totally chlorine free applies to virgin fiber papers that are unbleached

or processed with a sequence that includes no chlorine or chlorine

derivatives. (Also see ECF)

Translucent Drawing Paper

A paper suitable for drawing office use; sufficiently translucent for an

image on it to be reproduced by processes using transmitted light and for

a design to be traced on it from an original placed beneath it. Such

processes include blueprint and diazo.

Transparent Paper

Extended and particularly careful grinding of high quality fibers (hard

chemical pulps, rags) yields a raw material permitting the production of

transparent paper.

Treated Paper

Papers which have functional characteristics added through special

treatment. Among the most common are insect resistant, mold resistant,

clay coated, and flame retardant.


To cut true to exact size, by cutting away the edges of paper in the web

or sheet.

Tub Sizing

The operation of surface sizing paper by passing it through a bath of a

suitable solution such as gelatin.

Tube Digester

Single or multi-tube continuous digester; used mainly in nonwood pulping

and sawdust pulping purposes; horizontal tubes..

Twin-wire Machine

A papermaking machine with two continuous forming wires, rather than just

one. Twin-wires were designed to create a less two-sided paper than paper

manufactured on a Fourdrinier paper machine.

Other techniques for reducing two-sidedness have since been

developed, enabling paper manufacturers to create paper on single-wire

machines with little side-to-side variation.

Twisting Paper

A paper of high tensile strength in the machine direction which is cut

into narrow widths and spun or twisted into yarn or twine.

Two Parallel Fold

An excellent fold for legal size (or larger) pieces that are to be mailed.

A legal sheet (8.5″ x 14″) is folded to 3.5″ x 8.5″. A 9″ x 16″ sheet

produces a 4″ x 9″, four panel brochure. Note: A perforation added at one

of the folds can create a three panel brochure with detachable reply card.


The property denoting a difference in appearance and printability between

its top (felt) and wire sides.


Unglazed Paper

Un-calendered paper.

Union Kraft

A packaging material comprising two layers of Kraft paper bonded together

by means of a laminate that is resistant to the transmission of water in

liquid or vapor form. E.g. bitumen or plastic.

Un-sized Paper

A paper which has not been sized.

Urban Forest

A description of towns and cities which are the source of wastepaper as

one of the raw materials used for paper making.

Urban Wood

Used pallets, wooden shipping crates and clean construction wood diverted

from the waste stream and chipped for use in making particleboard and

medium density board.

UV Coating

A very glossy, slick coating applied to the printed paper surface and

dried on press with ultraviolet (UV) light. UV coating can cause slight

variations in match colors, so consult an ink manufacturer or printer for

best results.

UV Ink

An ink specially formulated to dry quickly with ultraviolet light while

still on press. Fast UV drying eliminates the need to wait for the first

side to dry before printing the second side.


V Fold

V-fold has one fold which creates two panels.

Vacuum Box

See Suction Box

Vat Machine

A paper or board making machine comprising one open ended cylinder, or

more than one open ended cylinder in series, covered with fine mesh wire,

which revolves in a vat of stock. Water draining through the wire leaves a

mat of fibers on its surface and the ultimate thickness of the product may

be determined by the number of cylinders used. The resultant web is

removed from the last cylinder and then passed through conventional

pressing and drying sections

Vegetable Parchment

Paper that has acquired, by the action of sulfuric acid, a continuous

texture. It offers high resistance to disintegration by water and grease.

Vegetable Parchment

Paper that has acquired, by the action of sulfuric acid, a continuous

texture. It offers high resistance to disintegration by water and grease.


The liquid part of the ink, giving it the flow properties that enable it

to be applied to a surface.


Uneven coloring of pulp.

Vellum Paper

(1) Paper finish that exhibits a toothy surface similar to eggshell or

antique and is relatively absorbent for fast ink penetration.

(2) A high-grade paper made to resemble parchments originally made

from calf’s skin.

(3) Social and personal stationery is often called vellum.

Virgin Fiber

Fiber that has never been used before in the manufacture of paper or other


Virgin forest

Forest in its natural state, untouched by man.

Viscose Pulp

Dissolving pulp intended for the manufacture of viscose.

Viscosity (ink)

A measurement of the fluidity of ink. A higher viscosity is the thicker,

and the lower viscosity is thinner.

Vulcanizing Paper

Paper made specifically for treatment with zinc chloride (ZnCl2) and

sulfuric acid (H2SO4) to gelatinize the surface cellulose. Vulcanizing

converts the paper in to a hard, dense and tough sheet which is used in

electrical insulation, luggage, mechanical assemblies and building




A single or multi-layer loosely matted fiber pad made from chemical pulp

and used in packaging, thermal insulation and /or acoustical applications.

It is also used in diaper and as absorbent material in other sanitary


Wall Paper

A paper used for wall covering. Also known as hanging paper.

Wall Paper

A paper used for wall covering. Also known as hanging paper.


The machine direction yarns in a woven fabric (press felt, dryer screen

etc.) See also weft

Wash Press

One type of pulp washer; uses pressing action for dewatering and



Japanese handmade paper. For more detail, please visit


A process of separating spent cooking or bleaching chemicals from pulp


Washing Deinking

Deinking in which solid particles are separated on the basis of their size

by washing. Also see Flotation Deinking and Combination Deinking.

Water Finished Paper

A high glazed paper produced by moistening the sheet with water or steam

during calendering.

Water Finished Paper

A high glazed paper produced by moistening the sheet with water or steam

during calendering.

Water Resistant Paper

Paper which has been impregnated, coated or laminated to resist the

penetration of water.

Water Retention Value (WRV)

The water retention value test provides an indication of fibers’ ability

to take up water and swell. The WRV is also highly correlated to the

bonding ability of kraft fibers.

Water Vapor Transmission

The rate of water vapor transmission through containerboard indicates the

ability of the finished container to protect its contents from undesirable

effects of high humidly or moisture loss of the product.

Water-Color Paper

A medium weight, hard sized, coarse surface paper, suitable for painting

with water based colors.

Water-Color Paper

A medium weight, hard sized, coarse surface paper, suitable for painting

with water based colors.


A paper with little or no sizing, like blotter, making it very absorbent

If dampening is desired, this paper can be sprayed with an atomizer.


The image impressed into the formation of paper by the dandy roll on the

wet end of the paper machine; can be seen by holding the watermarked sheet

up to the light. Can be either a wire mark or a shaded image.


A form of paper curl resulting when the sheet edges in the pile absorb

moisture that the center of the pile cannot absorb; or the sheet edges

surrendering moisture while the center remains moist.

Wavy Edges

Warping effect in paper that is the result of the edges of the sheet

having picked up moisture and expanded. Will normally happen only in a

pile that prevents the center of the sheets from picking up the same

amount of moisture and leveling out or cockling. It is usually a warm

weather problem caused by improper balance between moisture content of the

paper or too high humidity in the air.

Waxed Paper

Nearly woodfree papers that are impregnated with paraffin, wax or

wax/paraffin/plastic mixtures. With the appropriate saturation agent and

process the product may be tailored for specific applications, e.g.

packaging of bread or sweets or wrapping razor blades.


Coating or impregnating of paper or board with paraffin or wax.


Term used for the full width of the paper sheet in the process of being

formed, pressed, dried, finished and/or converted.

Web Break

A tear in a web during the printing process.


The cross machine direction yarns in a woven fabric (press felt, dryer

screen etc.). See also warp

Wet Break

A paper break at the wet end (on wire or press) during papermaking


Wet End

First part of the paper machine consisting of wire part and press part.

Wet Lap Machine

Paper machine consisting essentially of a wire covered cylinder rotating

in a vat of pulp stock on which a mat of varying thickness is formed by

drainage. These mats are removed either intermittently in thick sheets

called laps, or continuously.

Wet End Chemical Additives

Chemical additives added with the stock at the wet end. Following are some

of the wet end additives.



Acids and bases

To control pH


Control pH

Improves Retention

Attach additives on fibers

Part of Rosin-alum sizing

Coloring chemical (dyes & pigments)

Impart desired color


Kill/control foam to improve drainage & retention

Drainage Aids

Improve drainage (water removal) at wire/press.

Dry Strength Additives (Starches, Gum)

Improves burst, tensile, pick resistance etc.

Fiber Deflocculants

Reduce fiber flocculation and thus improve formation

Filler (clay, CaCO3, TiO2 etc.)

Improve opacity, printing, surface smoothness etc.

Optical Brighteners

Improve optical brightness

Pitch Control

Prevent deposition & accumulation of pitch

Retention Aids

Improves retention of fibers and fillers

Sizing Chemical ( rosin, ASA etc.)

To control liquid (water, ink etc.) penetration


Control slime growth and other organisms

Specialty Chemicals

Corrosion Inhibitors

Flame Proofing


Wet Strength Resin

To impart wet strength to such papers as coffee filter

Wet Strength Paper

A chemically treated paper strong enough to withstand tear, rupture or

falling apart when saturated with water.

Wet Tensile Strength

The measure of the force necessary to break a one inch strip if paper

after it has been immersed in water.

Wetting Agent

Substance that increases the wettability of a surface for a liquid.

White Liquor

White liquor is the aqueous solution of sodium hydroxide & sodium sulfide

used as the cooking liquor in Kraft pulping.

White Top Liner

A two-ply sheet comprised of one bleached and one unbleached layer.

White Water

The filtrate from the wet end of the paper machine.

White Water System

Flow circuit for paper machine white water (includes pipes, storage tanks,

cleaning equipment, water from forming section and return feed).


Whiteness of pulp and paper is generally indicated by its brightness,

which is the reflectance of a wavelength of blue light. So-called white

papers have a definite hue. Most are made with a blue white tint.

Whole Tree Chip

Wood chips produced by chipping whole trees, usually in the forest. Thus

the chips contain both bark and wood. They are frequently produced from

the low-quality trees or from tops, limbs, and other logging residues.


The bleeding of ink from the ink jet printing process into unwanted areas

of the paper, causing a blurring effect of the printed character or image.

Willesden Paper

Paper made waterproof by immersing in a bath of cuprammonium hydroxide,

washing and drying. The treatment partially dissolves and gelatinizes the

surface and the final paper is parchment-like, tough, waterproof, rotproof

and distasteful to insects. It is used for roof covering and insulating


Winder, Rewinder

Machine for cutting the paper web longitudinally into narrower webs, which

are then wound to reels; also slitter-winder


Operation whereby a web of paper or board is wound into one or more reels.

Wipes or Wiper

Folded absorbent tissue used for cleaning purpose.

Wire Guide Roll

The small diameter roll used for guiding (keeping on track) the wire. One

end of the roll is adjusted to compensate any misalignment.

Wire Mark

On the bottom or wire side of the paper, these are impressed traces of the

machine wire.

Wire or Machine Wire

The moving “screen” at the wet end of a paper machine where the sheet is


Wire Return Roll (s)

The small diameter rolls used at the return run (Couch roll to Breast

roll) of the wire.

Wire Side

The side of a sheet next to the wire in manufacturing; opposite from the

felt or top side; usually not as smooth as the felt or topside.

Wire Tension Roll

The small diameter rolls used at the return run (Couch roll to Breast

roll) of the wire to adjust the tension of the wire.

Wood Pulp

Mechanical or chemical pulp made from wood (cf. Non-wood pulp).


Pulp furnish without mechanical pulp.


The Paper having a uniform surface and no discernible marks. Soft, smooth

finish, most widely used writing, printing, book and envelope paper.

Relatively low opacity, brightness and bulk.


The materials, consisting usually of paper or paperboard, sometimes with

treatment for moisture barrier properties, which are used to protect the

roll or pile form damage.


Blade Wrinkle: Blade coating defect, an irregular line on the coated

surface, essentially in the machine direction.

Winder Wrinkle: Ridges at an angle to the machine direction, caused

by hard sport in the reel.

Writing Paper

Uncoated paper that is suitable for writing with ink on both sides. The

writing must neither bleed nor strike through. Writing paper is always

fully sized and also suitable for printing. It can be woodfree or

mechanical, depending on the intended purpose. The admixture of fillers

makes it less translucent.



The printing process used by photocopying machines. Electric charge

creates the image on an eloctro-photographic surface that works as a

plate. This surface is cleared after each copy is made, and used over

again for the next copy.


A type of hemi-cellulose in wood. Yellow, water-soluble, gummy

polysaccharide found in plant (e.g. hardwood or cereal straws) cell walls;

main structural components are xylose and other pentoses; yields xylose

and other pentoses upon hydrolysis.


Enzyme used for hydrolysis of xylan in pulp bleaching.


Yankee Machine

A type of Fourdrinier paper machine employing a single dryer of large

circumference with highly polished surface.

Yellow Pages

Used for telephone directory advertising. Paper used for this needs to

have high bulk (1.1 to 1.2), high tensile strength of about 2 kg/15 mm in

MD and good opacity (90%) so that the fine print made on thin paper like

40 gsm would be readable on both side. Excellent reel build up is required

for smooth feeding during printing. This requires every uniform profile of

bulk, gsm, caliper, moisture etc.


Or brightness reversion is the discoloration of white paper primarily due

to aging.


Ratio of product output and raw material input, expressed in percentage.



The direction perpendicular to the plane of a sheet of paper.

Z-Direction Tensile Strength

The tensile strength measured in Z-direction.

Zero (Effluent) Discharge

No effluent discharge from pulp & papermaking plant.


A paper fold represented by back and forth folds into three panels.

Zig Zag Folding

Folding used with continuous forms with alternating position (head and

foot). Commonly used to convert roll paper to easily managed flat-back

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