Patent ID: 6645362
Filing Date: 2003-11-11
Classification: B05D,Y10T

Abstract:
A method for forming a multi-layer paint film, comprising:applying a cationic electrodeposition paint (A) containing a block polyisocyanate compound as a cross-linking agent on a surface of a substrate, applying a water based intermediate coat paint (B) containing a block polyisocyanate compound as a cross-linking agent on the electrodeposition paint film surface without curing the electrodeposition paint film to form an intermediate coat paint film, and then heating to cure both of the electrodeposition paint film and the intermediate coat paint film at the same time to thereby form a multi-layer paint film, wherein said cationic electrodeposition paint (A) contains a tin base catalyst of at least 10 parts by weight per 100 parts by weight of the resin solid content, and a cross-linking curing reaction in the electrodeposition paint film is controlled so that it starts earlier than a cross-linking curing reaction in the intermediate coat paint film.