C1S:

Describes paper stock that is coated on one side.

C2S:

Describes paper stock that is coated on two sides.

CAB:

Shortened form of "cabriolet" or carrier; a glass, film, or paper carrier for negatives taped in position. Identical to the term 'flat" used in offset plate making.

Caking:

The collecting of ink particles upon rollers and plates caused primarily by the inability of the vehicle to hold the pigment in suspension. Also known as Piling.

Calender:

A process to make paper smooth or glossy by passing it through a series of metal rollers during the last steps of a papermaking machine.

Calender Cut:

Slits, glazed lines, or discolored lines across the paper caused when wrinkles pass through the calender rollers.

Calender Scale:

Foreign materials not strongly attached and randomly distributed on the surface of the web, appearing as shiny spots.This can cause nonuniform ink absorbency or lead to picking.

Calibration:

The process of adjusting a device or process to match certain criteria. This is usually done by measuring the device's deviation from standard values and then, during operation of the device, applying values to compensate the deviation. In prepress, in particular, calibration is the fine-tuning of scanners, monitors, printers, and image-setters in order to increase the accuracy of their output.

Caliper:

Thickness of a substrate expressed in thousandths of an inch (mils or points), pages per inch (ppi), thousandths of a millimeter (microns) or pages per centimeter (ppc), measured with a micrometer. (2) Device on a sheetfed press that detects double sheets or on a binding machine that detects missing signatures or inserts. (3) A disc brake pad or braking mechanism involving opposing brake pads that grip a rotating disc.

Callout:

1. A staging sheet prepared to initiate delivery of materials from the warehouse. 2. a visual device for associating annotations with an image, program listing, or similar figure. Each location is identified with a mark, and the annotation is identified with the same mark. This is somewhat analagous to the notion of footnotes in print.

Calls:

Seconds, paper with damage or imperfections outside mill tolerances.

Camera-ready Art:

Any artwork or type that is ready to be scanned for reproduction purposes.

Candela, cd:

The unit of luminous intensity. The candela is the liminous intensity, in a given direction, of a source emitting a monochromatic radiation of frequency 540 x 1012 Hz, the radiant intensity of which in that direction is equal to 1/683 Watt per steradian.

Capillary Action:

A phenomenon associated with surface tension and contact angle; examples are the rise of liquids in capillary tubes and the action of blotting paper and wicks.

Capture Efficiency:

The fraction of all organic HAP emissions generated by a process that are delivered to a control device, expressed as a percentage.

Capture System:

A hood, enclosed room, or other means of collecting organic HAP emissions into a closed-vent system that exhausts to a control device.

Carbon Black:

An intensely black, finely divided pigment obtained by burning natural gas or oil with a restricted air supply.

Carbon Tissue:

Light-sensitive material attached to gravure cylinders, used as a resist in the chemical etching process. It consists of layers of gelatin, dye, photosensitive material, and a paper or plastic backing. Exposed to a screen and a continuous-tone image, carbon tissue permits the etching of cells of variable depth according to the degree of exposure in each cell area. Until the advent of electronic engraving, the predominant method of imaging a cylinder.

Carbonless Paper:

Chemically coated paper so that duplicate copies can be produced without the use of carbons.

Carcinogen:

A substance known or suspected to cause cancerous growths in living tissues.

Carload:

Selling unit of paper that may weigh anywhere from 20,000 to 100,000 pounds (9,090 to 45, 454 kilos), depending on which mill or merchant uses the term. Abbreviated CL.

Carrier:

The backing material for labels. Labels consist of the printable material, the adhesive, and the carrier.

Case bind:

To bind using glue to hold signatures to a case made of binder board covered with fabric, plastic or leather. Also called cloth bind, edition bind, hard bind and hard cover.

Cast Coating:

Special paper-coating method using a heated, highly polished chrome drum, providing the smoothest and glossiest of all paper finishes.

Catalog:

A bound booklet of 16 or more pages promoting products or services of one organization.

Catalyst:

A substance that makes possible or enhances a chemical reaction, but which is not consumed in the reaction. Catalysts are added in various chemical processes (plating, ink drying) and are engineered, where possible, to be continually reused as other materials are removed and replenished.

Catalytic Coating:

Coatings formulated as two-part systems, available in both water- and solvent-reducible formulas. They use reactive resins that cure to form a thermoset film. They have heat and abrasion resistance, high gloss, sol- vent resistance, and adhere to a wide variety of substrates.

Cation:

A positively charged ion.

Cathode:

A negative electrode. In electroplating, the cathode is usually the item to be plated.

Cathode Efficiency:

The current efficiency of a specified cathodic process.

Cathode Film:

The layer of solution in contact with the cathode that differs in composition from that of the bulk of the solution.

Cathode Polarization:

The portion of the electrolyte in the vicinity of the cathode.

Cation:

A positively charged ion.

CCD:

(Charged-Coupled Device) A very small light-sensitive photocell that is sensitized by giving it an electrical charge prior to exposure. CCDs have a broad range of uses in graphic arts optical devices.

CD-ROM:

(Compact Disk-Read Only Memory) A medium for storing between 500 and 600 megabytes of digital information that can be retrieved repeatedly, but cannot be changed.

Cell:

A small etched or engraved depression in a gravure cylinder that carries the ink.

Cell Post:

The point at which the cells of four adjacent etched gravure cells meet, forming a common post that braces and adds strength to the walls. The dimensions and configuration of the cell post influence the wear life of the engraving and its ability to carry ink.

Cellosive™:

A trade name of Union Carbide Corporation for ethylene glycol monoethyl ether, a slow drying, active solvent.

Cellulose:

The essential structural material of all plants. In its pure state, an amorphous white carbohydrate, insoluble in ordinary organic solvents, made up of 44% carbon, 6% hydrogen, adn 50% oxygen, used to make paper.

Centipoise:

A unit of measure of viscosity; 100 centipoises equal one poise. Water has a viscosity of 1 centipoise (CP).

CEPS:

(Color Electronic Prepress System) A high-end computer-based system that is used to color correct scanned images and assemble image elements into final pages.

Certified Product Data Sheet (CPDS):

Documentation furnished by suppliers of inks, coatings, varnishes, adhesives, primers, solvents, and other materials or by an outside laboratory that provides the organic HAP content of these materials, by weight, measured using Method 311 of appendix A of this Part 63 or an equivalent or alternative method (or formulation data as provided in § 63.827(b)) and the solids content of these materials, by weight, determined in accordance with § 63.827(c). The purpose of the CPDS is to assist the owner or operator in demonstrating compliance with the emission limitations presented in §§ 63.824-63.825.

CGATS TR011:

Approved in 2002. The report, CGATS TR011 Graphic Technology, Package Development Workflow, Design Concept Through Approved Production File, provides guidelines for producing a packaging project from concept through an approved production file. It establishes tools, recommends roles and responsibilities of participants, provides default specifications for communicating color issues, and identifies guidelines and standards that can be used to further define required parameters. TR011 can help packaging companies with workflow development.

Chain Dot:

(1) Alternate term for elliptical dot, so called because midtone dots touch at two points, so look like links in a chain. (2) Generic term for any midtone dots whose corners touch.

Chain Lines:

(1) Widely spaced lines in laid paper. (2) Blemishes on printed images caused by tracking.

Chalking:

A condition resulting from the improper drying of ink. The vehicle has been absorbed to rapidly into the paper causing the pigment to dust off.

Channel:

Carbon black produced by impinging a natural gas flame against a metal surface.

Character:

A letter, number, punctuation mark, or special graphic used for the production of text.

Characterization:

The process of creating an ICC profile that describes the unique color characteristics of color reproduction devices such as monitors, scanners, color printers, and four-color presses.

Character Set:

(1) A finite set of different characters that is complete for a given purpose; for example, the character set in ISO Standard 646, "7-bit Coded Character Set of Information Processing Interchange." (2) A group of characters used for a specific reason; for example, the set of characters a printer can print.

Check Copy:

(1) Production copy of a publication verified by the customer as printed, finished and bound correctly. (2) One set of gathered book signatures approved by the customer as ready for binding.

China Clay:

A natural white mineral pigment used in paper coatings and as an ink extender.

Chlorinated Rubber:

A chemical compound of chlorine and rubber latex forming a binder for Type T gravure inks. Commercial trade names are Parlon and Alloprene.

Choke:

Technique of slightly reducing the size of an image to create a hairline trap or to outline. Also called shrink and skinny.

Chroma:

The attribute of color that specifies the amount of saturation or strength in the Munsell color space model.

Chromatic color:

Color exhibiting hue, as opposed to achromatic color.

Chromaticity coordinates (CIE):

The ratios of each of the three tristimulus values X, Y and Z in relation to the sum of the three, designated as x, y and z respectively. They are sometimes referred to as the trichromatic coefficients. When written without subscripts, they are assumed to have been calculated for illuminant C and the 2° (1931) standard observer unless specified otherwise. If they have been obtained for other illuminants or observers, a subscript describing the observer or illuminant should be used. For example, x10 and y10 are chromaticity coordinates for the 10° observer and illuminant C.

Chromaticity diagram (CIE):

A two-dimensional graph of the chromaticity coordinates (x as the abscissa and y as the ordinate), which shows the spectrum locus (chromaticity coordinates of monochromatic light, 380-770nm). It has many useful properties for comparing colors of both luminous and non-luminous materials.

Chromaticity--Chromaticity Coordinates:

Dimensions of a color stimulus expressed in terms of hue and saturation, or redness-greenness and yellowness-blueness, excluding the luminous intensity. Generally expressed as a point in a plane of constant luminance.

Chrome:

A slang term referring to a color trans-parency that is used as the original copy. Chrome is not incorrectly used as a short term for Cromalin.

Chromium Trioxide (Chromic Acid):

A chemical compound ("salt") consisting of one chromium atom bonded to three oxygen atoms, i.e., CrO3. This molecule ionizes in water to form chromium ions carrying a +6 charge. At the cathode, six electrons are supplied to each ion resulting in chromium metal, Cr. Chromium trioxide is a strong oxidizing agent and is toxic. It is commercially known as chromic acid.

CIE (Commission Internationale de l'Eclairage):

The International Commission on Illumination, the primary international organization concerned with color and color measurement.

CIE 1931 standard colorimetric observer:

One of the first mathematically defined color spaces. An ideal observer whose color matching properties correspond to the CIE color matching functions for the 2º field size.

CIE 1964 supplementary standard colorimetric observer:

An ideal observer whose color matching properties correspond to the CIE color matching functions for the 10º field size.

CIE 1976 L*a*b* color space:

A uniform color space utilizing an Adams-Nickerson cube root formula, adopted by the CIE in 1976 for use in the measurement of small color differences. Appropriate for use in additive mixing of light (e.g., color TV).

CIE 94:

The CIE94 tolerancing method utilizes three-dimensional ellipsoids as "containers" for color acceptance. CIE94 is conceptually similar to CMC2:1 but lacks some of the hue and lightness adjustments. It is expected that CIE94 will evolve over the next few years as additional studies are performed.

CIE L*a*b*:

A color model using lightness (L*) and two color values (a*&b*). The color coordinates define where a specific color lies in a Cartesian graph: the a* value defining a red-green axis and the b* value defining the blue-yellow axis. The L* value adding a third dimension to the color space.

CIE primaries:

The three standard primaries, defined by CIE in 1931 and called X, Y, Z, that can be used to match, with only positive weights, all visible colors. The Y primary is intentionally defined to have a color-matching function that exactly matches the luminous-efficiency function of the human eye.

CIE standard illuminants:

Known spectral data established by the CIE for four different types of light sources. When using tristimulus data to describe a color, the illuminant must also be defined. These standard illuminants are used in place of actual measurements of the light source.

CIE standard observer:

A hypothetical observer having the tristimulus color-mixture data recommended in 1931 by the CIE for a 2° viewing angle. A supplementary observer for a larger angle of 10° was adopted in 1964. If not specified, the 2° Standard Observer should be assumed. If the field of view is larger than 4°, the 10° Standard Observer should be used.

CIE Tristimulus Values:

Amounts of the three components necessary in a three-color additive mixture required for matching a color: in the CIE System, they are designated as X, Y, and Z. The illuminant and standard observer color matching functions used must be designated; if they are not, the assumption is made that the values are for the 1931 CIE 2° Standard Observer and Illuminant C. CIE Chromaticity Coordinates: x and y values that specify the location of a color within the CIE chromaticity diagram.

CIE xy Chromaticity Diagram:

A two-dimensional graph of the chromaticity coordinates, x as the abscissa and y as the ordinate, which shows the spectrum locus (chromaticity coordinates of monochromatic light, 380-770nm). It has many useful properties for comparing colors of both luminous and non-luminous materials.

CIE XYZ color space:

The cone-shaped space formed by (x, y, z) weights, that when applied to the CIE primaries, match any visible color.

CIELAB (CIE L*a*b*) color space:

The color space in which L*, a* and b* are plotted at right angles to one another. Equal distances in the space represent approximately equal color difference.

Clean Hole:

A paper defect caused by restricted drainage on the wire in the paper machine in the absence of any foreign matter or contamination.

Cleaning:

The removal of grease or other foreign material from a surface. In electroplating, cleaning implies readying the surface of the metal to be plated to allow acceptable plating to occur.

Clipping:

The severe transformation of colors that are re-purposed to another device's color gamut. These colors lie within the original color space but outside the destination color space.

CMC (Colour Measurement Committee of the Society of Dyes and Colourists of Great Britain):

Developed and published in 1988 a more logical, ellipse-based equation based on L*C*h° color space for computing DE (see delta E*) values as an alternative to the rectangular coordinates of the CIE LAB color space.

CMM:

Color management module. A set of color algorithms used to transform color values. The CMM is the engine that calculates color values based on predefined color characteristics in the ICC profiles.

CMS:

Color management system. This is system-level functionality that maps, or translates, the color space of one device to the color space of another. ColorSync on the Mac OS and ICM 2.0 on Windows are examples of CMSs.

CMYK (Cyan, Magenta, Yellow and Black):

The four so-called process colors (technically, they are "subtractive" colors) that are used in four-color printed reproduction. In desktop publishing it's one of the color models; the others being HSB, PMS and RGB.

Coarse Screen:

Halftone screen with ruling of 65, 85 or 100 lines per inch (26, 34 or 40 lines centimeter).

Coated Freesheet:

The highest grade of gravure coated paper, containing no groundwood and offering the highest brightness.

Coated Groundwoods:

The most widely used grade of paper for gravure-printed magazines, classed as #5 Publication Coated papers.

Coated paper:

Paper with a coating of clay and other substances that improves reflectivity and ink holdout. Mills produce coated paper in the four major categories cast, gloss, dull and matte.

Coating Operation:

The application of a uniform layer of material across the entire width of a substrate.

Coating station:

A workstation on which a coating operation is conducted.

Cobwebbing:

A filmy, web-like build-up of dried ink or clear material on the doctor blade, or on the ends of impression rolls.

Coefficient of Friction:

The ratio of the frictional force resisting movement of the surface being tested to the force applied normal to that surface (the weight of the material above that surface).

Cohesion:

Attraction that causes the particles of a substance to become united throughout its mass.

Cold Color:

In printing and separations, colors which are on the bluish or greenish side. An additive or subtractive solution may be found with a print viewing filter kit if a color correction is needed.

Cold Seal:

An adhesive product that can be applied on a gravure press. The adhesive only adheres to itself and is usually printed in a registered pattern. It is most commonly used for frozen confectionary packaging.

Cold Soda Process:

A variation of chemical pulping in which pulp is processed at room temperatures.

Collate:

The assembly of signatures or sheets in reading sequence for binding.

Collating Marks:

Mostly in the book arena, specific marks on the back of signatures indicating exact position in the collating stage.

Color:

The perceived shade or hue of an object, based upon the reflected light. Paper is generally described as white, but most sheets have a slight colorcast, a slight tinge of yellow, red or blue.

Color Balance:

Maintaining the ratio of cyan, magenta, and yellow ink during printing. This will keep all color hues consistent and produce a picture with the desired color, one without an unwanted color cast or color bias.

Color blanks:

Press sheets printed with photos or illustrations, but without type. Also called shells.

Color Blocks:

Small square patches of a single color attached to artwork to indicate colors specified by the artist; or also placed on cylinders to indicate ink colors to be used in the press.

Color Break:

In multicolor printing, the point, line or space at which one ink color stops and another begins. Also called break for color.

Color Cast:

An unwanted overall discoloration of an original copy, color proof or reproduction caused by an overabundance of one color pigment or light. Color casts result in bluish red, pinkish blue, etc. reproduction. The color cast can be digitally altered during or after scanning by using gamma correction.

Color control bar:

Strip of small blocks of color on a proof or press sheet to help evaluate features such as density and dot gain.

Color correction:

The process of adjusting an image to enhance color reproduction. Adjustment can be done locally or overall. Color correction can be done through hue change or gradient curve change on an electronic system or through conventional etching.

Color curves:

Instructions in computer software that allow users to change or correct colors. Also called HLS and HVS tables.

Color difference:

The magnitude and character of the difference between two colors under specified conditions.

Color Electronic Prepress System:

Computer, scanner, printer and other hardware and software designed for image assembly, color correction, retouching and output onto proofing materials, film or printing plates. Abbreviated CEPS.

Color Key:

A printer's proof, actually four sheets of colored acetate, for examining the quality of process color separations. This process is normally used when printing on a press capable of fewer than four colors at once. All AA's and corrections should have been made prior to seeing a color key.

Color Management:

Matching colors between an orginal image, scanner, monitor, color printer and final press sheet.

Color Matching Functions:

The tristimulus values of monochromatic stimuli of equal radiant power.

Color Measurement:

Physical measurement of light radiated, transmitted or reflected by a specimen under specified conditions and mathematically transformed into standardized colorimetric terms.

Color Model:

A color measurement scale or system that numerically specifies the perceived attribute or color. Used in computer graphics applications and by color measurement instruments. . See CMYK, PMS and RGB.

Color Picker:

A utility for specifying colors on a computer monitor.

Color Proof:

A representation of what the final printed composition should look like. The resolution and quality of different types of color proofs can vary greatly.

Color Resolution:

The number of bits that record the color for one pixel. This is also known as bit depth or color depth. The higher the color resolution, the greater range of possible colors in the image, and the larger the file size. Typical color resolutions are 8-bit, 16-bit, or 32-bit, although others are possible.

Color saturation:

Describes the amount of gray in a color. The more gray, the lower the saturation; the less gray, the higher the saturation.

Color Separation:

Literally separating the areas of a piece to be printed into its component spot and/or process ink colors. Each color to be printed must have it's own printing plate.

Color Sequence:

Order in which inks are printed. Also called laydown sequence and rotation.

Color Shift:

In-process printing, the undesired change in a printed image's appearance during the run.

Color Space:

The parts of the visible spectrum that can be reproduced in a given medium (i.e., RGB for computer monitors, CMYK for print, web safe index colors for online sites).

Color Strength:

The effective concentration of coloring material per unit of volume.

Color Temperature:

A measurement of the color of light radiated by an object while it is being heated. This measurement is expressed in terms of absolute scale, or degrees Kelvin. Lower Kelvin temperatures such as 2400°K are red; higher temperatures such as 9300°K are blue. Neutral temperature is gray, at 6504°K.

Color Transparency:

A photographic image on transparent film used as artwork.

Color Wedge:

A tone scale showing graduated tones in primary printing colors, with or without density readings.

Color Wheel:

The visible spectrum's continuum of colors arranged into a circle, where complementary colors such as red and green are located directly across from each other.

Colorant:

The color portion of an ink, may be a pigment, dye or combination of the two.

Colorimeter:

An optical measurement instrument that responds to color in a manner similar to the human eye by filtering reflected light into its dominat regions of red, green, and blue.

Colorimetric:

Of or relating to values giving the amounts of three colored lights or receptors—red, green, and blue.

Color-Matching Functions:

Relative amounts of three additive primaries required to match each wavelength of light. The term is generally used to refer to the CIE standard observer color-matching functions.

ColorSync:

Built-in color management architecture for Apple Macintosh computers. Third-party vendors utilize the ColorSync framework to provide device calibration, device characterization, and device profile-building methods.

Comb Bind:

To bind by inserting the teeth of a flexible plastic comb through holes punched along the edge of a stack of paper. Also called plastic bind and GBC bind (a brand name).

Comets:

Intermittent ink deposits in the shape of a comet's tail. Sometimes referred to as Darts. See also –Soft Streaking.

Commercial Printer:

Printer producing a wide range of products such as announcements, brochures, posters, booklets, stationery, business forms, books and magazines. Also called job printer because each job is different.

Comp:

Comprehensive artwork used to present the general color and layout of a page.

Compatibility:

The ability of two or more differing solutions or substances to be mixed together without resultant kick-out or haziness.

Complex Ion:

An ion composed of two or more ions or radicals, both of which are capable of independent existence, for example cuprocyanide Cu(CN)-3.

Complementary Colors:

Colors that can be additively mixed to produce as achromatic color.

Complementary Wavelength:

The wavelength of the monochromatic stimulus that, when additively mixed with the color stimulus considered, matches the specified achromatic stimulus.

Complements:

Two colors that create neutral gray when combined. On a color wheel, complements are directly opposite from each other

Complexing Agent:

A compound that will combine with metallic ions to form complex ions. See also - Complex Ions.

Composite Image:

A photograph or other graphic image that is made of a combination of multiple images.

Composition:

(1) In typography, the assembly of typographic elements, such as words and paragraphs, into pages ready for printing. (2) In graphic design, the arrangement of type, graphics and other elements on the page.

Compound:

A wax, grease or other material intended to be added to an ink to improve laying, prevent offset, sticking and picking, and to shorten or reduce an ink.

Comprehensive Dummy:

Simulation of a printed piece complete with type, graphics and colors. Also called color comprehensive and comp.

Compressibility:

The behavior of paper under pressure, such as that applied by the gravure impression roller. A function of basis weight and caliper. No separate test for compressibility exists, but it is evaluated during tests for smoothness.

Condition

To keep paper in the pressroom for a few hours or days before printing so that its moisture level and temperature equal that in the pressroom. Also called cure, mature and season.

Conductance:

The capacity of a medium, usually expressed in ohms, for transmitting electric current.

Conductivity-Specific Conductance:

The current transferred across unit area per potential gradient. In the metric system, K = amperes per square centimeter divided by volts per centimeter. The reciprocal of Resistivity.

Cones:

Photoreceptors in the retina that contain light-sensitive pigments capable of initiating the process of photopic vision.

Consistency:

Refers to the body characteristics of an ink.

Constant Gloss Test:

A paper test for gloss used on matte or uncoated papers, used to determine if undesirable reflections will hamper readability of the printed sheet under normal viewing conditions.

Contact Angle:

Actual wiping angle of blade on cylinder. Resultant of forces at work in the particular application.

Contact Area:

Area of blade in actual contact with print cylinder when wiping.

Contact Positive:

A positive made from a negative by exposure to light in a contact frame, either continuous tone or screened.

Continuous Tone:

Term used to describe any camera or scanner input material that has varying tones of gray formed by the grain pattern of a photographic emulsion, made without the use of screens or dots. All traditional photo- graphs (prints and transparencies) are continuous-tone materials.

Contrast:

The tonal gradation between highlights, middle tones, and shadows in an original or a reproduction. This is the visual relationship of the original to the reproduction when comparing white to black ranges.

Contrast Range:

The amount of variance between highlights and shadows in an original or halftone, quantified as the difference between the top highlight and deepest shadow density readings as measured by a densitometer.

Conversion:

The process of creating a 3-D item from a flat sheet of paper, such as envelope conversion or box conversion.

Control Limits:

The amount of acceptable variation in press capabilities over the course of a press run.

Converter:

Business that makes products such as boxes, bags, envelopes and displays.

Converting:

The processing of a web material from one form to another. Converting processes include calendaring, coating, die cutting, embossing, laminating, printing, punching, sheeting, slitting, treating, winding and unwinding.

Copper Cyanide:

Source of copper ions in an alkaline cyanide electrolyte. Copper cyanide is a toxic substance.

Copper Plating:

The process of applying a coating of copper to a base cylinder by electrolytic means.

Copper Sulfate:

CuSO4• 5H20. Source of copper ions in an acid copper-plating bath. Toxic by ingestion.

Copy:

All furnished material or disc used in the production of a printed product.

Copy Viewer:

Any device for viewing copy, such as an overhead light from viewing reflective copy, or a light box for viewing transparencies.

Core:

A hollow tube or spool, often of fiber, plastic, or metal, upon which a roll is wound. Most cores are 3-inches ID except for the jumbo rolls that require 6-inch ID.

Corona Treatment:

A high-voltage discharge and ionization of the air in the space above the moving web, causing ozone to form. The ozone, a powerful oxidizing agent, affects the surface of the substrate, improving the ability of inks and coatings to adhere it.

Corrugation Marks:

A paper defect having the appearance of "rope" or "chain" marks parallel to the direction of web travel, caused by adjacent hard and soft spots.

Coulomb:

A current of one ampere flowing for one second (one amp-second).

Cover Paper:

A heavy printing paper used to cover books, make presentation folders, etc.

Coverage:

Extent to which ink covers the surface of a substrate. Ink coverage is usually expressed as light, medium or heavy.

Covering Power:

The ability of a plating solution under a specified set of plating conditions to deposit metal on the surfaces of recesses. (To be distinguished from throwing power).

Crash:

Coarse cloth embedded in the glue along the spine of a book to increase strength of binding. Also called gauze, mull and scrim.

Crawling:

See also - Mottle.

Creasing:

The folding of a sheet material without the appearance in the zone of folding cracks, sharp lines of bending failure, splitting away of surface coating, or other unsightly manifestations of fractures. This should be carefully distinguished from brittleness, as the latter involves a small degree of bending.

Creep:

Phenomenon of middle pages of a folded signature extending slightly beyond outside pages. Also called feathering, outpush, push out and thrust. See also Shingling.

CREF (Computer Ready Electronic Files):

Designed by a number of printers and separators to draft a flexible set of standards or guidelines for preparing desktop publishing files for successful output to film. See also – Mechanical.

Crimping:

Puncture marks holding business forms together.

Cromalin:

A color-proofing system created by DuPont. All AA's and corrections should have been made prior to seeing a Cromalin.

Crop:

In order to eliminate portions of the copy, photograph or artwork, crop marks are placed on the original or overlay to indicate which portions are to be eliminated. Careful cropping can save money in the final separation stage because color separations are billed for their final reproduction size on film, not just the portion being used at the printing stage.

Crop Mark:

A line printed outside the finished size of a piece that shows where the piece is to be cut to size.

Cross-Deckle Misregister:

Misregister caused by shrinking of a web between printing units. Cure or Curing-(l) Conversion by chemical reaction of a wet coating or printing ink film to a solid film. (2) Also refers to the addition of a catalyst.

Crosshairs:

A single or series of engraved cells in the shape of a cross, engraved on an image carrier. Used to visually check register, predominately for skew.

Crossover:

Type or art that continues from one page of a book or magazine across the gutter to the opposite page. Also called bridge, gutter bleed and gutter jump.

Crystallization:

A condition in which a dried ink film repels a second ink that must be printed on top of it.

CT:

(Continuous Tone) A file format used for exchanging high-level scan information.

Cure or Curing:

(1.) Conversion by chemical reaction of a wet coating or printing ink film to a solid film. (2.) Also refers to the addition of a catalyst.

Current Density:

Current per unit area. (1.) Average total current divided by the total area of the electrode in solution. (2.) The value of the current density at a given point on the electrode.

Current Efficiency:

The ratio of liberated to theoretical mass: in an electrolytic process, the mass of the substance liberated by a current divided by the theoretical mass, as predicted by Faraday's law.

Customer Service Representative:

Employee of a printer, service bureau, separator or other business who coordinates projects and keeps customers informed. Abbreviated CSR.

Cut:

To dilute an ink, lacquer or varnish with solvents or with clear base; to thin.

Cutoff:

A specified length of converted material, usually relating to a gravure cylinder repeat length.

Cutting Die:

Usually a custom ordered item to trim specific and unusual sized printing projects.

Cutting Machine:

A machine that cuts stacks of paper to desired sizes. The machine can also be used in scoring or creasing.

CWT:

A unit of weight measurement created by U.S. merchants in the late 1800s. A hundred weight is equal to exactly 100 pounds. C is the Roman numeral for the number 100 and WT is the abbreviation for weight, i.e., 100 lbs.

Cyan:

A shade of blue used for process color printing.

Cyanide:

A cyanide is any chemical compound that contains the cyano group -C≡N, with the carbon atom triple-bonded to the nitrogen atom. The CN group can be found in many kinds of compounds. Some are gases, others are solids or liquids. Some are salt-like, some covalent. Some are molecular, some ionic, and many are polymeric. Those that can release the cyanide ion CN− are highly toxic.The anion CN, widely used in electroplating processes. It must be used in alkali form (pH greater than 7) to prevent formation of hydrogen cyanide gas (HCN), which is extremely toxic.

Cylinder:

Rollers in the printing press upon which the rubber plates are mounted and which receive the impressions.