CATHODIC ELECTRODEPOSITION COATING MATERIAL COMPOSITION

摘要

PROBLEM TO BE SOLVED: To provide a cathodic electrodeposition coating material composition which can form a corrosion-resistant coating film particularly on an untreated cold-rolled steel sheet without using a toxic rust preventive pigment. SOLUTION: This cathodic electrodeposition coating material composition comprises an aqueous dispersion containing both a hydrophilic film-forming resin having a cationic group and a crosslinking agent, which composition contains an organic acid and/or a cerium salt of an organic acid, and cerium carbonate and/or cerium pyrophosphate and wherein the metallic cerium derived from the cerium carbonate and/or cerium pyrophosphate accounts for 0.05-10 mass% of the coating material solids.