A pigment of the class of pigments which are usually mixed directly from the earth, dried and ground. They are frequently also termed "natural pigments". Most earth pigments consist of complex mixtures of iron or manganese oxides with aluminium silicates. Typical examples are red and yellow oxides of iron, yellow ochre, raw sienna and raw umber.

The final appearance of a scan that has been enhanced to produce more data than the scanner can record. This is done by interpolation.

The point at which a mesh when under tension will no longer return to its original size.

This term is sometimes used incorrectly in the context of an ink or varnish film to describe its flexibility. In this sense its use is not recommended.

The complete range of electromagnetic waves, as measured by wavelength. Different wavelengths have different properties. These include sound, radio, microwave, heat, light, ultra-violet, X-rays, cosmic rays.

Process used in digital halftone production that allows negatives or plates to be generated by grouping micro dots into regular groups to function in the same manner as a photographically produced halftone.

A process of imaging where a "toner" is used to form an image by controlled static charges. Toner printing adheres to the charged areas.

Measurement of the amount of stretching.

Used as a term with reference to screen printing mesh. It is the degree to which a mesh will stretch and still return to its original size.

An object that emits light and/or other radiant energy, such as the burning gasses of the sun or the heated filament of a light bulb.

In scientific terminology this is an homogeneous material formed by the incorporation of two liquids which are normally immiscible. It is also the term applied to the photosensitive material used to produce photopositives used in pad printing. In screen printing the coating applied to the mesh during the creation of a stencil is also known as the emulsion.

The side of photographic film or paper coated with the light sensitive silver halide emulsion. Film output is specified for use as emulsion up, or emulsion down.

The improvement of an image either through colour and/or density change.

To remove metal by chemical or electrochemical means in order to produce an image on a printing Plate.

An inorganic mixture in powder form which has little obliterating power, but is used as a constituent of inks to adjust the properties of the ink. A liquid material added to an ink to increase its transparency. See also "Varnish".

The destruction of colouring matter in a printed surface as a result of ageing, weathering or exposure to sunlight.

Wisps of ink around the printed image, normally caused by static charges in the component or pad. Can be a result from the ink being too thick. Also called static, splashes, wisps.

The material used for blocking out. Also a material added to an ink to increase opacity. Much cheaper than pigment. Normally this is chalk or china clay.

Determination of the print characteristics of a printing press. This will give the dot gain curves to allow compensation during production of original file.

The surface property of a material determined by its surface contour and gloss.

A fault in the stencil emulsion normally caused by dirty mesh. An undesirable circular flaw in the printed image usually caused by bubbling of the ink.

Lifting of the ink from the underlying surface in the form of flakes or scales (poor adhesion).

The treatment of the surface of polyethylene and polypropylene by passing through a gas/air flame (alternative system to Corona Discharge). Can also be used to accelerate the drying of ink

A liquid having a flash point below 100 degrees Fahrenheit (37.8 degrees C).

Non image-forming illumination, e.g., scattered light that causes a "haze."

The minimum temperature of a saturated vapour of a specified liquid at which the vapour will ignite in the presence of a spark or flame. The flashpoint is an arbitrary figure and depends on the method of test.

A technique of imaging graphics from regions of solid colour with no gradations at all. Often used in fabric and wallpaper imaging.

A low-gloss finish, with little reflective quality.

A scanner that utilises CCD linear arrays, where the image is placed on a glass platen, and the array moves past the artwork.

The degree to which an ink film, after drying, is able to conform to movement or deformation of its supporting surface without cracking or flaking.

Printing from a rubber roller; i.e. direct rotary printing using resilient raised image plates.

The process by which an aggregation of pigment particles in ink form clusters or chains changing the hue and/or chroma of that ink. Also called Livering.

Flock is precision-cut lengths of nylon or rayon fibres which vary in length from .5 mm to 5 mm and also vary in denier. It is applied electrostatically onto an adhesive.

A weathering panel exposed in Florida at 45 degrees to the sky and facing south. Generally, considered to be one of the harshest exposures to sunlight.

The degree to which a wet ink film can flow out after application so as to eliminate marks and thus produce a uniform surface on drying.

An additive used to disturb the surface tension and increase the ink flow.

A physical process at which the materials pigments absorb light and re-radiate this light as a different colour, giving the colour of the material extra light or brilliance.

Refers to an object that is mounted directly to a surface, with no raised surface space between, i.e.: "Flush Mount Letters."

A dithering method that uses uniform dot sizes and varies the distance between them. This method is different from conventional halftone screening, which aligns dots of varying sizes on a regular grid.

Term for donor medium for thermal-transfer printing; usually involves wax-based or resin-based colorant on rolls of thin plastic that travel over heated print head and are placed on a substrate by combinations of heat and pressure by the printer. Also, a very thin, metal sheet of various alloys used mainly as an overlay, veneer, or cut out appliqué.

Historically, an assortment of letters and/or numbers, all the same size and type having a pre-determined amount of each letter or number. The term today refers generically to letter styles.

A unit used to measure light, a measure of illuminance, light level incident on a surface. LUX x .0929 = Foot candles

Printing Reproducing full colour by photographically separating the art into its three primary colours: process yellow, magenta and cyan plus process black and printing them in that configuration. All these colours are transparent.

Printing term used when an image or background extends to the final trim edge of a printed page