A4 Paper:

ISO-defined paper size 210 x 297mm used for letterhead.

Abrasion:

The process of wearing down by friction. Surface damage casued by rubbing of a part against another part or surface.

Abrasion Resistance:

The ability of a material to withstand actions such as rubbing, scraping, or erosion that tend progressively to remove material from its surface.

Abrasion Test:

A trial designed to determine the ability to withstand the effects of rubbing and scuffing.

Absolute Humidity:

The mass of water vapor per unit volume of air in the atmosphere.

Absolute White:

In theory, a material that perfectly reflects all light energy at every visible wavelength. In practice, a solid white with known spectral reflectance 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.

Absorbency:

That property of a porous material, which causes it to take up liquids or vapors.

Absorption:

The penetration of one substance into the mass of another.

Acid-free Paper:

Paper made from pulp containing little or no acid so it resists deterioration from age. Also called alkaline paper, archival paper, neutral pH paper, permanent paper and thesis paper.

Accordion Fold:

Bindery term, two or more parallel folds which open like an accordion.

Acetate:

A transparent type of plastic. The term is often used to refer to a sheet made of this plastic that can be used for overhead transparencies.

Acetone:

A very active solvent used in packaging gravure inks. The fastest-drying solvent in the ketone family.

ACFM:

Actual cubic feet per minute of air flow—i.e., air flow in drying sytems or catalytic/thermal oxidizers.

Achromatic Color :

Devoid of hue (white, black, grey, neutral).

Acidity:

PH of the paper that tests below 7, usually 5-6

Activated Carbon:

A highly absorbent form of carbon used to remove odors and toxic substances from liquid or gaseous emissions.

Addition Agent:

A material added in small quantities to an electroplating solution to modify the character of the deposit produced by the bath.

Additive Primaries:

Red, green, and blue light. When all three additive primaries are combined at 100% intensity, white light is produced. When these three are combined at varying intensities, a gamut of different colors is produced. Combining two primaries at 100% produces a subtractive primary, either cyan, magenta, or yellow: 100% red + 100% green = yellow; 100% red + 100% blue = magenta;   100% green + 100% blue = cyan

Adhesion:

(1.) The sticking together of any two materials, e.g., adhesion of ink to paper or film. (2.) The attractive force that exists between an electrodeposit and its substrate that can be measured as the force required to separate the two.

Adhesives:

Glues, fixatives or waxes that bind coated paper ingredients together.

Adsorb:

To attract and hold molecules on a surface, i.e., solvent molecules in a solvent-recovery adsorption bed.

Aerosol:

A broad term applied to any suspension of solid or liquid particles in a gas. The particles can be liquid (mist) or solid (dust or fume).

After-tack:

Tack that develops after ink has apparently dried or after a heat-drying operation.

Against the Grain:

At right angles to the grain direction of the paper being used, as compared to with the grain. Also called “across the grain” and “cross grain.”

Age Stability:

A test to determine whether an ink formulation can withstand a specific temperature for a specified period without change.

Agglomerate (Agglomeration):

A cluster of undispersed particles.

Aggregate:

A chain of undispersed particles or clusters.

Agitation:

A stirring or mixing action; setting in violent or irregular motion.

Air Knife Coating:

A paper-coating method wherein a thin blade of air is used to apply coating to the sheet evenly.

Air Stripping:

A treatment system that removes volatile organic compounds (VOCs) from contaminated ground water or surface water by forcing an airstream through the water and causing the compounds to evaporate.

Alcohol:

A series of organic compounds characterized by the presence of the hydroxyl group; volatile solvents, the most common being ethyl alcohol.

Algorithm:

A sequence of exact instructions that define a method to solve a particular problem. For example, algorithms are used to create a digital halftone screen.

Aliphatic Solvents:

Saturated hydrocarbon solvents derived from petroleum, such as hexane, heptane, and VM&P naphtha, used primarily in A-type gravure inks or as diluents for other inks and coatings.

Alkali Resistance:

Property of an ink, coating, or substrate so that it resists film breakdown, color change, or color bleed when printed material is subjected to contact with alkaline materials such as soap or detergent.

Allotophic:

Term referring to substances existing in different colors or forms, usually due to different crystal structures; carbon black and a diamond are allotropic forms of carbon.

Alteration:

Any change made by the customer after copy or artwork has been given to the service bureau, separator or printer. The change could be in copy, specifications or both. Also called “AA,” “author alteration” and “customer alteration.”

Alumina Hydrate:

A white inorganic pigment used as an extender in inks and noted for its transparency. Also known as hydrate.

Always-Controlled Workstation:

A workstation associated with a dryer from which the exhaust is delivered to a control device, with no provision for the dryer exhaust to bypass the control device. Sampling lines for analyzers and relief valves needed for safety purposes are not considered bypass lines.

Ambient Conditions:

Temperature, pressure and other characteristics of the surrounding air.

Ambient Temperature:

Normal fluctuating temperatures in an environment that are not closely controlled, e.g., in a typical warehouse, boxcar, office building, etc.

American National Standards Institute (ANSI):

A non-profit, privately funded voluntary membership organization that develops national consensus standards for a wide variety of devices and procedures.

Amine:

Class of organic compounds derived from ammonia.

Ampere:

The current that will deposit silver at the rate of 0.001180 grams per second. Current flowing at the rate of one coulomb per second.

Angle Bar:

A metal bar or roll used either singly or in succession to reorient the web direction.

Angle of Wipe:

Angle the doctor blade is set from the centerline of cylinder, before loading. Also called Set Angle.

Anhydrous:

Containing no water.

Aniline Ink:

Known as flexographic ink.

Anilox Roll:

Mechanically or laser-engraved ceramic or chrome-plated steel roll that has been engraved with cells that carry and transfer liquids (varnishes, adhesives, inks, scents, etc.). Used in flexo presses.

Anion:

An ion having a negative charge. Because of this charge, anions are attracted to the anode in an electrolytic cell

Anode:

The positively charged electrode in an electrolytic cell. In an electroplating operation, the anode is frequently the source of the plating metal (soluble anodes, as in copper plating).

Anode Film:

(1.) The layer of solution in contact with the anode that differs in composition from that of the bulk of the solution. (2.) The outer layer of the anode itself, consisting of oxidation or reaction products of the anode metal.

Anode Polarization:

The material upon which coatings are deposited.

Anodized Plate:

An offset printing plate having a treated surface in order to reduce wear for extended use.

Anti-aliasing:

The rendering of hard-edged objects so that they blend smoothly into the background. A technique for merging object-oriented art into bitmaps.

Antifoaming Agent:

An additive that prevents or eliminates foam in ink.

Anti-Offset Spray:

A dry or liquid spray attachment on presses to prevent ink from transferring from the top of one printed sheet to the bottom of the next.

Antioxidant:

An agent that retards the action of oxygen in drying oils and other substances subject to oxidation.

Appearance:

Visual attributes of an object such as size, shape, color, texture, glossiness, transparency, opacity, etc.

Application software:

A computer program or system designed to perform specific tasks. Broad examples of computer applications are word processing and spreadsheet programs, computer aided design and illustration, and applications for management and administration.

Aquatint:

An early plate-engraving method that created tonal variation by etching through granular material with varying concentrations of etchant. Used only for fine art engraving.

Aqueous Coating:

Coating in a water base and applied like ink by a printing press to protect and enhance the printing underneath.

Area Mask:

An outline mask that isolates a specific area of an image either by shape, color or tone value.

Aromatic Solvents:

Unsaturated hydrocarbon solvents such as, toluene and xylene, originally derived from coal tar, but now made from petroleum. They possess excellent solvent properties for Type-A inks.

Artboard:

Alternate term for mechanical art.

Artwork:

All original copy, including type, photos and illustrations, intended for printing. Also called art.

Artifacts:

A visible indication (defect) in an image, caused by limitations in the reproduction process (hardware or software).

Artificial daylight:

Term loosely applied to light sources, frequently equipped with filters, that attempt to reproduce the color and spectral distribution of daylight. A more specific definition of the light source is preferred.

ASCII:

An acronym for American Standard Code for Information Interchange. A standard format for representing digital information in 8-bit chunks.

Ash Content:

Mineral residue left after burning a piece of paper

Attribute:

Distinguishing characteristic of a sensation, perception or mode of appearance. Colors are often described by their attributes of hue, chroma (or saturation) and lightness.

Author's Alterations (AAs):

At the proofing stage, changes that the client requests to be made concerning original art provided. AAs are considered an additional cost to the client usually.

Autotrace:

A computer operation that traces the edges of simple shapes in a bitmap so that they can be stored as vector-based objects, which can be edited or manipulated by a drawing/ illustration program.

Azeotrope:

A mixture of solvents that exhibits a constant maximum or minimum boiling point.