The application of organic barrier coatings is one of the methods for steel protection against corrosion. The protective action of such coatings consists, principally, in reducing the permeability of electrolytes and gases through a paint film. The reduced permeability of water vapour, oxygen and electrolytes is greatly dependent on the thickness and structure of the paint film (i.e. the vehicle type), the degree of organic binder crosslinking, the pigment volume concentrations, and the type and particle shape of the pigments and fillers. In barrier coatings, only pigments and fillers which are completely insoluble in water are used. Lamellar pigments and fillers are considered to be the most suitable for this purpose. They demonstrate a tendency to orientate in parallel to the substrate and to form an inorganic barrier inside the organic coating rendering the penetration of aggressive media difficult. Among lamellar pigments and fillers, one may distinguish non-metallic materials such as mica, micaceous iron oxide, glass flakes and metallic flakes of aluminium, zinc, stainless steel, nickel and cupro-nickel.