A - Z list of keywords and terms from the coatings industry.



Hard settlement of pigments in a coating, which is not easily re-dispersed by stirring.

Carbon Black

The most intense black pigment, virtually pure carbon, made from the incomplete combustion of petrochemical oils.


The pan-European trade association of the coatings industry, the Confederation European des Associations de Fabricants de Pientures, d'Encres d'Impriemerie et de Couleurs d'Art includes as sitting members the National Trade Associations and, as Corporate Associate Members, many of the major pan-European coatings producers. It promotes the interests of the industry, particularly with the Community and other international organisations. Health, safety and environmental issues are of particular concern.


Powdering effect experienced on coating after exposure to weathering.


A black, porous material left over when wood or bones are burned without a full air supply. Consists almost entirely of carbon.


Formation of short, shallow cracks on a coating film.

Chemical Resistance

Some coatings have to be used in situations in which they have a resist chemical attack on themselves the substrate. Polyurethane & Epoxy resins are frequently used as the binder for such coatings.

Chlorinated Rubber

Natural rubber which has been chlorinated and is soluble in organic solvents.



Coated profiled sheets of steel or aluminium used for walls or roofs of buildings.


A process of grading particles of power according to particle size. Sieves or air vortexes may be used, particularly to remove 'fines' that may cause problems in application equipment.


The top, clear coat of a car coating system. Usually used in vehicle refinishing, as well as for original painting of cars.

Coalescing Solveny

Coating System

Term used to describe the layers of coatings applied or specified for a particular project.


Spider's web effect , generally noticed in spray application. Usually caused by the solvent /thinner evaporating too quickly at the spray tip.


Term used to describe the internal strength of a coating.

Coil Coating

Painting (and/or laminating with sheet plastic) metal in coil from before forming the metal into cladding or finished components. Also known as refinishing.

Cold Checking

Formation of short, shallow cracks due to a sudden drop in tempertaure.

Colour Fast

Ability of a coating (or pigment) not too fade.

Colour Retention

Ability of a coating to retain its original colour.


Ability of a coating to be intermixed or applied onto another coating.

Convertible Coating

Forms film that will not re-dissolve in the original solvent and are characterised by undergoing a chemical change when drying

Correct Colour

On some coatings systems, such as primers and undercoats, high levels of colour accuracy are not important. In most topcoats and inks, however, accurate colour is vital, and the aim is always to keep consistency of colour between batches, as well as matching the standard. On each batch, therefore, the aim is to set the colour between the last batch and the standard. Colours may be compared by eye using various standard illuminations in a light cabinet. More usually they are also compared using colour computers, which can not only measure the closeness of the match, but can calculate the amounts of stainers required to improve the match to the standard colour. A key problem in matching colours is to make sure that the match is acceptable, not just in daylight but also in, say artificial light. Colours that match in one light but do not match in other lights are said to show metamerism.


The process of oxidisation of a metal. Seen on iron or steel as rusting, it may be accelerated by moisture or chemical in the air.

Corrosion Resistance

The ability of a coating system to prevent or slow corrosion, often achieved by the inclusion of pigments based on metallic zinc or compounds of zinc, strontium, lead or calcium. Good adhesion and water resistance of the coating is generally also important, to prevent access of moisture to the metal substrate. Other systems offer corrosion resistance such as coating with zinc (galvanising) and may be used on their own or in conjunction with a coating system.


The area that will be covered by a volume of coating, norammly express as square metres per litre.


Non-uniform, deep cracks in the coating.


The process by which polymers become interlinked to form a solid, three-dimensional matrix. Chemical bonds are formed between neighbouring molecules of the polymer(s) present, by allowing them into contact by evaporation of solvent; or by heating; or by chemical reaction using a cross-linking agent.

Cup Gun

A conventional air assisted spray gun with the paint supplied from a small reservoir fitted either on top or below the gun.


Converting the wet or powder applied coating to a dry, continuous film by the application of heat, a reactive chemical, some form of radiation or atmospheric action.

Curing Agent

Normally a term used to descibe a component in 2 Pack coatings that is involved in the curing / hardening / drying process.

Curtain Coating

A method of applying a liquid industrial coating by passing a substrate (which is usually flat) at a steady speed under a 'curtain' of the coating.


A Machine into which powder coatings are blown during manufacture, which uses an air vortex to separate oversized particles (which drop through the centre), undersized powder dust (which is blown out of the current of air) and powder of the correct particle size, which is collected for packing.

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