Resistance to frictional rubbing as distinct from resistance to knocks and impacts. Abrasion tests may be made by means of the finger alone, or with a cloth or a pad with or without a mildly abrasive powder. The pressure, speed and time of rubbing as well as the character of the rubbing agent should be controlled when making comparisons of abrasion resistance.

Acrylonitrile-butadiene-styrene, a thermoplastic. Hs good impact resistance and a surface that is easily decorated.

In theory, a material that perfectly reflects all light energy at every visible wavelength. In practice, a solid white with known spectral data used as the "reference white" for all measurements of absolute reflectance.

A solvent, or other material, which is added to an ink in order to increase its drying rate, i.e.. to make it dry quicker.

Cellulose based thermoplastic

Neutral colour & white, grey, or black & that has no hue.

A thermoplastic. A common one is known commercially as "Perspex"

An adhesive made of acrylic polymers.

Ink with an acrylic component.

Actinic light is a light that causes a chemical reaction to take place. Ultra violet light is an example.

The three additive primary colours are red, green and blue. When these three colours of light are mixed in equal proportions, they will produce white light. Also known as additive primaries.

The power of an ink to stick to the surface on which it was printed. In general, measured by scratching off method, using a fingernail, or a pull-off method using self-adhesive tape (Scotchtape test). The measure of the strength by which two materials bond together.

Test methods used to determine the adequacy of ink coating adhesion to a substrate. A common test is the Cross-cut tape test.

A mathematical routine that solves a problem or equation. In imaging, the term is usually used to describe the set of routines that make up a compression or colour-management program.

The visual stair-stepping of edges (jagged edges) that occurs in an image when the resolution is too low. Can be caused by improper image sampling or improper image processing.

The official US standards organisation, the U.S. member of the International Standards Organisation (ISO), responsible for industry standards.

Undesirable fine threads of ink caused when the ink pulls away from the printed surface. (see cobwebbing)

The smoothing and removing of aliasing effects by electronic filtering and other techniques, such as blending of hard edges. Also, blending object-oriented art with bit-mapped art.

The percentage of dot coverage in a specific area, as measured using a densitometer.

The difference between the Apparent Dot Area of the film, as measured by a transmission densitometer, and the Apparent Dot Area of the proof or printed sheet, as measured with a reflection densitometer.

(See "Water Based").

Laboratory test designed to simulate, but at the same time to intensify and accelerate the destructive action of natural weathering on ink films. The test involves exposure to artificially produced components of natural weather, e.g. light, heat, cold, water vapour, rain, etc. which are arranged and repeated in a given cycle.

British Standard.

A material which in itself is not an ink, but which may be used to produce an ink, as in extender base.

The non-volatile portion of the vehicle of an ink; it binds the pigment particles together to form the ink film and binds that film to the material to which it is applied.

The fourth colour in four-colour printing. It is listed as the K in "CMYK." Black is required in the printing process because equal amounts of cyan, magenta and yellow inks will not produce a true black; ideally, the complete absorption of incident light; the absence of any reflection. In the practical sense, any colour which is close to this ideal in a relative viewing situation, i.e. a colour of very low saturation and of low luminance.

The addition of black ink to the other process colours when separating an RGB colour image into CMYK colours. Black generation is typically handled in one of two ways, GCR or UCR.

Loss of colour in an ink. This may be due to internal chemical or physical action in the ink itself; to influences from the surface on which it is applied; or to weathering or contamination from the atmosphere.

Migration of an ink component or dye into an area it is not wanted. Can also be the running of a pigment colour by action of the solvent. Also: Extension of an image or background beyond the trim edge of a page.

Technology in its first phase of development.

An unwanted adhesion between layers of material placed in contact under moderate pressure and/or temperature in storage or use. Usually occurs when stacked prior to thorough drying.

The process used during stencil production where areas left without emulsion but not part of the image are filled with a material that stops ink passing through the mesh.

A deposit like the bloom on a grape which sometimes forms on gloss ink or varnish films, causing loss of gloss and dulling of the colour. Sometimes bloom may be removed by wiping with a damp cloth. It is usually the result of too rapid solvent evaporation which causes condensation of moisture on the surface.

One of the three additive primary colours of light.

A milky opalescence which sometimes develops as a film of ink dries and is due to the deposition of moisture from the air and/or precipitation of one or more of the solid constituents of the ink; usually confined to inks which dry solely by solvent evaporation.

The apparent viscosity of an ink or varnish, as assessed subjectively when applying a shearing force, e.g. when pouring material from a can, stirring it or otherwise spreading it over a surface.

Dimension of colour that is referred to an achromatic scale, ranging from black to white; also called lightness or luminous reflectance or transmittance (q.v.).

Brightness The overall intensity of the image. The lower the brightness value, the darker the image; the higher the value, the lighter the image will be.

A characteristic metallic lustre shown by certain highly coloured pigments in full strength, e.g. certain Prussian Blues.

A printing defect which may result in the dry print containing a lot of small air bubbles.

Another word for ink film.

Cellulose based thermoplastic.