CATION ELECTRODEPOSITION COATING METHOD AND COATED MATERIAL OBTAINABLE THEREFROM

摘要

PROBLEM TO BE SOLVED: To provide a cation electrodeposition coating method which is capable of forming a coating film having high filiform corrosion product resistance by subjecting the surface of an aluminum blank to chemical conversion treatment with a surface treating agent not containing heavy metals, such as chromium ions, and a coated material obtainable therefrom. SOLUTION: The cation electrodeposition coating method or subjecting the surface of the aluminum blank to electrodeposition coating with a cation electrodeposition coating material composition includes a process step of previously subjecting the surface of the aluminum blank to the chemical conversion treatment by using the surface treating not containing the heavy metals, in which the cation electrodeposition coating material composition contains a resin composition having a sulfonium group and propagagyl group. The coated material is obtained by the cation electrodeposition coating method described above.