PULP AND PAPER DICTIONARY
This page contains definitions of the terms, words and phrase commonly used in pulp and papermaking, printing, converting and paper trading.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
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.
BACKBONE 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.
BACK WATER See White Water.
BAFFLE 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.
BAGASSE Sugarcane residue left after extracting the juice.
BAGGY ROLL Mill roll defect usually associated with a variation in calliper 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.
BALE 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.
BALING Compressing and wrapping a material with wire, twine, string to form a unit which is more readily handled, stored and transported.
BAMBOO A plant of grass family grown in Asian countries and used for papermaking fibres.
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 fibres.
BARK 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 An 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.
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 fibres. Basic dyes are economical, have high colour strength but very poor light fastness.
BASIS WEIGHT In English system of units, Weight per unit area of a paper product. Reported in grams per square meter (gsm) or 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 Fibres derived from the bark of some annual plants such as flax, gampi, hemp, jute, kozo and mitsumata etc. Main characteristic of these fibre 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.
BATH TISSUE Also called bathroom tissue, toilet paper, or just TP. Its primary use is to clean and dry the skin after eliminating bodily wastes. It is supplied in roll form in most of the world, perforated for easy dispensing. Embossing is used to increase bulk, absorbency ,softness, and product roll size.
BEATER An equipment used for beating, refining and mixing pulps.
BEATER DYE Dye added to the beater to colour the pulp.
BEATER LOADING Addition of a filler to the pulp in the beater.
BEATING OR REFINING The mechanical treatment of the fibres in water to increase surface area, flexibility and promote bonding when dried. One of the unintended effect of beating is fibre length reduction.
EFFECT OF DEGREE OF BEATING ON PAPER PROPERTIES Properties Increased Decreased
Apparent Density Increases Decreases
Calliper Decreases Increases
Compressibility Decreases Increases
Dimensional Stability Decreases Increases
Formation More Uniform, less wild Less Uniform, more wild
Hardness/Softness Harder Softer
Ink Holdout Becomes more Becomes less
Internal Bond Strength Increases Decreases
Porosity Decreases Increases
Smoothness Increases Decreases
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.
BINDER Chemicals which facilitate fibre bonding.
BINDER (COATING) A natural or synthetic compound used to adhere coating to the paper surface.
BIOCIDE A biological control chemical such as fungicide or a bactericide used in papermaking.
BIODEGRADABLE Capable of destruction by biological action.
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.
BIOLOGICAL WASTE WATER TREATMENT A method of cleaning up waste water using living micro-organisms such as bacteria
BIOMASS 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.
BIO-SLUDGE Sludge formed (in the aeration basin) during biological waste water treatment or other biological treatment process.
BITOKOSHI 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) recognises 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.
BLACKENING Defect associated with calendared paper occurring as unintended local areas of apparently darker or greyer colour due, for example, to the paper being too damp when passed through the calendar.
BLANK OR BLACK BOX A flat sheet of corrugated or solid fibreboard 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.
BLADE COATER A device that first applies a surplus coating to paper and then remove extra colour after evenly levelling by means of a flexible steel blade.
BLEACH PLANT Section of a pulp mill where pulp is bleached
BLEACHING 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 .
BLEED 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 side.
BLENDING OR MIXING Blending of different pulps in a chest to achieve quality of the final product.
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.
BLISTER 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 surface .
BLISTER RESISTANCE Resistance of paper to developing blister during printing and print drying.
BLOTTING PAPER An un-sized paper used generally to absorb excess ink from freshly written manuscripts, letters and signatures.
BLOW 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.
BLUE ANGEL It is label defined by the German Federal Environmental Agency. The Blue Angel label is awarded to papers which do little damage to the environment. The paper is controlled in detail: its composition, its production process and its conversion. Only papers made from 100 % post consumer waste paper are certified..
BOARD 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).
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 fibres 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 fibres from coming loose ("picking"). Bonding strength of fibre 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.
BOX A rigid container having closed faces and completely enclosing its contents.
BOXBOARD A class of board frequently lined on one or both sides, with good folding properties and used for making box and cartons.
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 meters.
BREAKS 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/fibreglass/granite covered roll located at the headbox side of the paper machine to support the wire.
BRIGHTNESS The reflectance or brilliance of the paper when measured under a specially calibrated blue light. Not necessarily related to colour or whiteness. Brightness is expressed in %.
CIE BRIGHTNESS: An internationally-recognised standard of paper brightness developed in Europe by the Centre Internationale d'Eclairage (CIE).
BRISTOL BOARD A fine quality cardboard made by pasting several sheets together, the middle sheets usually of inferior grade.
BRITTLENESS Property of paper causing it to break while bending.
BROCADE A heavily embossed paper.
BROKE 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 floor.
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 colour-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 Coating method in which the freshly applied coating colour is regulated and smoothed by means of brushes, some stationary and some oscillating, before drying.
BUFFERING 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.
BULK Reverse of density, expressed as cubic centimetre per gram.
BULK A measure of the height of a stack of paper. The terms thickness and caliper usually refer to a single layer of paper. The number of layers in the stack varies from company to company, as well as what constitutes a single layer. Forbase paper, one layer usually consists of a single ply of paper. For the finished product, in its final form, one layer is often a unit of product, which may be several plies combined together. Some companies use the term "bulk" to mean thickness divided by basis weight, which is essentially a measure of specific volume. The test result is very dependent upon how much compressive force is applied to the product by the test instrument. The effect of embossing upon bulk is more obvious when a relatively light compressive force is used.
BURNOUT The loss of colour during drying.
BURNT PAPER Paper, which has been discoloured and is brittle, but otherwise intact.
BURST 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 calliper 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 test.
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.