IMPROVEMENT OF ADHESIVE STRENGTH OF PAINT FILM FORMED BY ANIONIC ELECTRODEPOSITION

摘要

PURPOSE:To improve the adhesive strength of a paint film to the plating of a plated article by subjecting the article to electrolysis as a cathode in an aqueous soln. contg. sexivalent Cr ions and by coating the article by anionic electrodeposition. CONSTITUTION:A plated metallic or synthetic resin material is subjected to electrolysis as a cathode in an aqueous soln. contg. sexivalent Cr ions as an electrolytic bath to form a colorless transparent chromate film contg. sexivalent Cr on the surface of the plating of the plated material. The chromate film is coated by anionic electrodeposition. Since the chromate film acts as a binder, the adhesive strength of the resulting paint film to the plating is improved.