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Glossary

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b* (ClE Starlab):
Refers to the system used to describe and measure color. b* indicates yellowness, a positive value, and blueness, a negative value.

BACKBONE
The bound edge of a book; also called a spine.

BACK CYLINDER PRINT
An image unintentionally printed on the backside of the paper. In offset lithography, a printing malfunction, where the ink image is transferred from the blanket to the impression cylinder, and then to the back side of the next sheet of paper run.

BACK LINING
A paper or fabric adhering to the backbone or spine in a hardcover book.

BACK PRESSURE
See impression; the squeeze pressure between the blanket cylinder and the impression cylinder, usually measured in thousandths of an inch.

BACKING UP
Printing the reverse side of a sheet already printed on one side. The name given to the process of feeding paper through a press a second time to print the other side.

BACKTRAP MOTTLE
This is the printed surface mottle resulting from improper ink tack sequence, with a subsequent color not wet trapping, uniformly on a previous color. Also, see mottle.

BAGGY ROLL (of paper)
Refers to a roll with nonuniform draw; the web width does not uniformly support web tension. There are slack and tight sections across the width of the web, and these are usually caused by stretched portions in the paper resulting from a ridge, rope or other defect in the machine direction. This condition can result in web tension difficulties in subsequent operations.

BAKING
A term given to the procedure of drying coatings onto papers.

BAR CODES
Machine-readable (often OCR), preprinted vertical bars used extensively in labeling, for automated materials handling, inventory control, and point of sale terminals. A multitude of systems exists, usually not compatible with each other and the respective reading devices.

BARRIER COAT
A coating that is applied onto the non-printing side of paper to add to the opacity or stability of the paper.

BASE PAPER/STOCK
Paper made for further converting by coating, laminating, etc. The paper for coating or other types of finishing including laminating and consisting mainly of fibers, but may contain other additives depending on its use. For example, for coated printing papers it will contain filler and sizing, but may also be surface sized.

BASIC
See alkaline sizing and pH.

BASIC SIZE
The sheet size (dimensions) of a ream of paper (usually 500 sheets) used to determine basis weight; see basis weight. The generally recognized sheet size from which the basis weight is determined. The basic size of book paper is 25 X 38 inches.

BASIS WEIGHT
Weight per a selected unit of area of a grade of paper; grammage or "grams per square meter" is used throughout the world and scientifically in the United States; the U.S. uses many different basis weight designations, depending upon the type of paper, including in fine paper, but not limited to: lbs. per 25" X 38"-500 sheets: text, book, offset lbs. per 17" X 22"-500 sheets: writing, bond, ledger lbs. per 20" X 26"-500 sheets: cover lbs. per 24" X 36"-500 sheets: newsprint, tag, tissue, board The 500 sheets represent the standard "ream" count, and is the basic unit for determining area. Also called substance weight, particularly in the bond or business grades of paper. The weight in pounds of a ream of paper, typically consisting of 500 sheets cut to its basic size.

BAUME' HYDROMETER
See hydrometer; a flotation device used to give the specific gravity, density, and thus concentration of a solution. Can be expressed in Baume' units.

BEARERS
Rings of steel at the ends of offset printing press plate and blanket cylinders that make rolling contact on impression for meshing of drive gears and for structural support of wide press cylinders. These rings are raised above the cylinder plane to provide a fixed base for determining the packing of plate and blanket.

BEATER
Large, longitudinally partitioned vat used to mix and mechanically work pulp with other ingredients to make paper. See refining.

BEATING
The mechanical treatment of the fibers in water to increase surface area, flexibility and promote bonding when dried. See refining.

BEKK SMOOTHNESS
The smoothness of paper as measured by the Bekk instrument, expressed as the time required for a given volume of air to flow between the measuring surface and the paper surface.

BELT PRESS
A printing press that uses two continuous belts for printing books in an inline operation from a paper roll to a delivered book block, ready for binding at the end of the press. Individual polymer plates for each pager are mounted on the belts. The plates are raised types. The most common belt press is the Cameron.

BIBLE PAPER
Thin printing paper for use in deluxe productions such as bibles, dictionaries and high-quality publicity productions.

BILL OF LADING
Transportation term referring to the contract between a supplier and carrier, listing number of packages, total weight, and address of destination.

BINDER
Material in a coating or ink which holds the coating or ink together and to the paper surface.

BINDERY
A department in a book manufacturing plant that takes the paper after printing, folds it, collates the signatures and binds them into a finished book. This department also makes the covers.

BIOCHEMICAL OXYGEN DEMAND
The amount of dissolved oxygen, measured in parts per million, utilized in the aerobic biochemical oxidation of the decomposable organic matter in facility wastewater.

BIOCIDE
See slime.

BLADE COATER
A device that first applies a surplus coating to a paper web and then evenly levels and distributes it by means of a flexible steel blade.

BLADE COATING
The coating method which uses a knife blade to apply a smooth and level, but non-uniform thickness, of coating to the surface of a sheet of paper. The primary paper coating process.

BLADE SCRATCH
See blade streak.

BLADE STREAK
Also called blade scratch; a very fine line or indentation in the coated surface (less than 1/8" wide), in the machine direction, and varying in length from a few feet to several hundred feet. Streaks can be visible under low angle illumination on the surface or appear less opaque than the general coated area when viewed by transmitted light. This defect can sometimes be observed as an actual cut in the sheet, when the streak is deep enough to sever the sheet. The blade streak, scratch or cut is caused by a piece of fiber, dried coating or coating ingredient, or other foreign material being caught under the blade for a period of time, during the blade coating operation.

BLANKET-TO-BLANKET PRESS
An offset lithographic perfecting press that has no impression cylinders; during printing, the blanket for one side acts as the impression cylinder for the other side, and vice versa. Also called perfecting press unit.

BLANKET CREEP
See creep.

BLANKET GAP
See cylinder gap.

BLANKET
A fabric coated with rubber or other synthetic material which is clamped around the blanket cylinder and which transfers the ink from the press plate to the paper.

BLEACHING
The material or the process used to whiten paper pulp; while cellulose fibers are naturally transparent and appear white in Color, wood impurities and staining colorants are encountered in the pulping process giving the fibers a brownish color, as in grocery bags, which are unbleached Kraft pulp. Chemical pulps are bleached in multiple stage processes (3 to 7 stages), with materials like chlorine, chlorine dioxide, hypochlorites, peroxides or ozone (the last 2 being oxygen type bleaching materials). Pertains to the type of bleaching the pulp has been exposed to. The three types are ECF, Non-ECF and TCF. The purpose is to remove color from the pulp.

BLEED
An extra amount of printing image which extends beyond the trim edge of the sheet or page. 1) An illustration that extends to one or more of the edges of a printed piece; bleed illustrations are usually printed 1/8" beyond the planned trim edge(s). 2) Term applied to a lithographic ink pigment, which dissolves in the fountain solution and causes it to be tinted. 3) The discoloration of dyed pulp and paper due to the removal of color by liquid, thereby making it susceptible to staining other materials it contacts.

BLINDING
In offset lithography, a condition of the plate where the image has lost its ability to accept and/or transfer ink.

BLISTER
An undesirable result that occurs in paper arising from the rapid expansion of moisture in the interior of a well-sealed sheet, when subjected to high drying temperatures; occurs most frequently on a heat-set, web offset printing press. Caused by too rapid or too high temperature drying, or a weak internal bond strength of the paper. Small eruptions in a paper's coating, usually from paper being dried too quickly on high-speed web offset presses.

BLOCK-OUT INKS
Inks applied to selected areas of some plies of multiple part business forms, such that any transferred image is unreadable in or on that printed area. The block-out ink is usually the same color as the transferred image or darker, so that any image transferred in or on that printed area is unreadable. These inks might be used to block out a price that does not need to be known by an individual ply recipient.

BLOCKING
The sticking together of a stack of sheets or paper in a roll, because of wet ink or coating.

BLOTTING PAPER
Very absorbent and bulky, wood free paper, sometimes made from a pulp of cotton or wool fibers.

BMI
Book Manufacturing Institute, a leading nationally recognized trade association of the book manufacturing industry responsible for producing the majority of books ordered annually by the U.S. book publishing industry. The Institute plays a leading role within the industry by providing an intra-industry communications link among book manufacturers and between book manufacturers, publishers, suppliers and governmental bodies.

BOARD
The board material used to make the covers of hardback books. Sometimes called binder board.

BODY
A term referring to the viscosity or flow characteristics of an ink or vehicle; an ink with too much body is stiff or is said to have high consistency.

BOLD FACE
Heavy line characters or type, in contrast to normal or light-face type; used for emphasis, captions, sub-headings, etc.

BOND
Class of printing/writing papers made from bleached chemical wood pulps and cotton fibers.

BONDED AIRLAID
a thermal bonding process in which airlaid fibers are cured in a large oven and passed through heated rollers to create an overall or a patterned bond.

BOND PAPER
Originally referred to paper used for printing BONDS and other certificates, but now a generic term applied to business papers; also called writing, or ledger (heavier weight); generally are less opaque than an equivalent weight book paper and are measured on a 17" X 22" basic size. Bond paper normally used in any office for copier, laser printer, and general typing or writing

BOND STRENGTH
An intralayer binding force in a paperboard or laminate. This term also refers to the degree of adherence of coating and film on a sheet and to the binding force in a sheet. See plybond.

BONE DRY (b.d.)
This term refers to the moisture-free conditions of pulp paper. It also refers to air containing no vapor.

BOOK BLOCK
A partially bound book without its cover.

BOOK JACKET
Paper which is printed and folded over the cover of bound books for protective and advertising purposes. These papers are usually 80-110 lb. coated one-side, and are often UV coated or film laminated by the book manufacture.

BOOK MANUFACTURER
A company whose business is to manufacture books for the publishing industry. These companies offer a wide range of services ranging from prepress to final product.

BOOK PAPERS
Also called text or offset. A general term for a group of coated, uncoated or film coated papers suitable for graphic arts. Book Papers are made from all types of virgin, reclaimed and recycled pulps and mixtures thereof in basis weights usually ranging from 30 to 100 lbs. (25 X 38). They are characterized by a wide variety of finishes such as Antique, Eggshell, Machine Finish, Dull Coated, Matte Coated, Gloss Coated and Film Coated. Most book papers are made to a precise thickness, which becomes critical in the binding process. Book papers are generally more opaque than an equivalent weight bond paper.

BOOK PAPER, PREMIUM
As the name implies, these are high cost papers. Their most important qualities are high opacity with low caliper or thickness. These papers also have very high longevity properties.

BOOK PAPER, UNCOATED
Term descriptive of those papers (exclusive of newsprint) that are most suitable for use in the graphic arts, particularly in the commercial, book and publication sectors. They can be wove or laid with a wide range of finishes. Basic size: 25 X 38. Basic weight: 22 to 150 lbs.

BRAILLE PAPER
Smooth, high strength papers suitable for the production of raised dots needed to manufacture reading material for the blind.

BREAKING LENGTH
A mathematical calculation based on paper's tensile strength and grammage. This represents the theoretical length of a uniform width of paper that, when suspended by one end, would break by its own weight. See tensile.

BREAST ROLL
The first or number one roll over which a Fourdrinier wire passes, as the furnish exits the slice.

BRIGHTNESS
The reflectivity of paper for a specified blue light measured under standard conditions, on an instrument (brightness meter) calibrated and designed for this purpose. In paper, is the amount of light, diffusely reflected from a surface, compared to that which would be reflected from a block of bright Magnesium Oxide; measurement is made with a specific wave length of light (blue), with the surface of an opaque pad of paper being illuminated at a 45 degree angle and the reflection being measured at a 90 degree angle; the human eye sees only reflected light, and brightness influences printed contrast and the amount of illuminating light which is reflected.

BRISTOL BOARD
A good quality board made from rag content papers prepared or plied together, usually with a thickness of .006" and up. Types of bristols include engraver bristols, folding, index, and wedding bristols.

BRISTOLS
A heavyweight paper possessing higher-than-average quality characteristics.

BROADSIDE
Any large advertising circular.

BROKE
Paper trimmings or paper damaged from breaks on the paper machine and in finishing operations. The term applied to wastage in the manufacture and finishing of paper, in the paper mill. Technically, the wastage that occurs on the paper machine, prior to subsequent finishing operations. Most broke or wastage in the paper mill is returned to the paper machine furnish for reprocessing into saleable paper.

BROKEN CARTON
A carton of paper that has been opened and some of its contents removed.

BRUSH FINISH
A paper that is run under stiff brushes, after coating, to give a high finish.

BUCKLES
1) The edge of a roll, usually only part of the diameter, where the paper along that edge is thinner and longer than the balance of the width of the paper on the roll. To compensate for this extra length, it buckles as it is wound. 2) In the binding operation of making books, usually from dry paper, buckles can develop along the bound edge. The paper picking up moisture and increasing in dimensions, resulting in extra dimensions influencing durability causes this and corresponding poor appearance buckles being formed.

BUCKLE FOLDER
A fold or folding device which accomplishes a fold in a sheet or signature. The sheet or signature is fed against a constrained flat stop to affect a bend in the sheet, which is completed into a fold by the action of two rollers, pinching the sheet at the point of buckle or maximum bend.

BUFFER
In offset lithography, a material to maintain an acid condition and stable pH in the press fountain solution.

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
The thickness of paper, commonly measured in four sheet thickness and expressed in terms of pages per inch. Measure of the density, or the thickness in relation to the basis weight of a sheet of paper; used in the binding of books and is measured as pages per inch (ppi). Individual sheet calipers do not necessarily total to ppi, because of how the sheets pack together. See caliper.

BULKING DUMMY
A given number of blank sheets of paper folded and put together to determine the actual thickness of a book. An estimate of book thickness prior to the manufacturing process.

BUM
In plate making, a common term used for exposing the plate.

BURST
A rupture in a web of paper resulting from stresses caused by adjacent areas of high and low caliper, too tight winding of adjacent areas of high and low caliper, or just too tight winding where the wound in tension exceeds the ultimate strength of the paper.

BURSTER
A business forms handling device for detaching continuous forms at cross perforations.

BURSTING STRENGTH
The resistance of paper to rupture when pressure is applied to a side by a specified instrument. This is also referred to as burst and pop strength. See Mullen test.

BUSINESS FORMS BOND
A bond paper manufactured for the specific requirements of web printing and converting and the end use of continuous business forms.

BUTT SPLICE
Formed by trimming the ends of two webs of paper, placing them end-to-end, and pasting a strip over and under to make a continuous web without overlapping. See splice.


 
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