The coating is generally composed of film forming materials, fillers (pigments and fillers), solvents and additives. Sometimes the composition will change slightly according to the performance requirements, for example, there is no pigment or filler in the varnish, and there may be no solvent in the powder coating.

It belongs to organic chemical polymer material, and the film formed belongs to the type of polymer compound. According to the classification of modern chemical products, coatings belong to fine chemical products. Modern coatings are gradually becoming a kind of multifunctional engineering materials and an important industry in the chemical industry.