Patent ID: 7507440

Claim:
A method of forming a composite coating upon the surface of a substrate, comprising the steps of: (a) applying a first powder base coating composition to the surface of the substrate to form a first base coat; (b) applying a second powder base coating composition to the first base coat to form a second base coat; (c) applying a liquid or powder top coating composition to the second base coat to form a transparent top coat and thereby form a composite coating; and (d) heating the composite coating so as to substantially cure the composite coating; the application and heating steps being conducted in the following ways: (1) prior to heating the first base coat, applying the second base coating composition comprising an effect pigment in flake or platelet form to the first base coat; (2) heating the first and second base coats to a temperature sufficient and for a period of time sufficient to melt and substantially level the second base coat composition and allow migration of the effect pigment to a surface region of the second base coat but not sufficient to cause the second base coat to cure; and (3) applying the top coating composition to the second base coat after the heating step and heating the resultant composite coating at a temperature and for a period of time sufficient to substantially cure the entire composite coating.