Colouring is one of the physical properties of a surface coating and is key to the optical appearance of a component.

In the area of technical surfaces – for example in engineering –  the coating is often merely required to meet fundamental requirements of colouring such as “black” or “silver”. In contrast, decorative surfaces - such as in the car industry - have very specific requirements for the colouring of components. The colour tones are specified in detail to achieve the desired surface. The coating or top coat is subsequently co-ordinated precisely to this. This involves precise colour impressions being determined in accordance with the CIE system (CIELAB system as per EN ISO 11664-4)., under defined artificial lighting and with the aid of special colourimetric values.