CHROMIUM-FREE PROCESS FOR IMPROVING THE ADHERENCE CHROMIUM-FREE PROCESS FOR IMPROVING THE ADHERENCE OF PAINT APPLIED BY THIN-FILM ANODIC OXIDATION OF PAINT APPLIED BY THIN-FILM ANODIC OXIDATION

摘要

PCT No. PCT/EP96/00829 Sec. 371 Date Sep. 8, 1997 Sec. 102(e) Date Sep. 8, 1997 PCT Filed Feb. 29, 1996 PCT Pub. No. WO96/27698 PCT Pub. Date Sep. 12, 1996A process for improving the adherence of paint applied after thin-film anodization is characterized in that the anodized metal surfaces are brought into contact with an aqueous solution containing one or more of the following components: (a) 200 to 2000 ppm of a homopolymer or copolymer of acrylic acid, methacrylic acid, and/or their esters; (b) 200 to 3000 ppm of a poly(vinyl phenol) compound in which at part of the phenol rings carry an alkylamino substituent; (c) 200 to 3000 ppm of hexafluorotitanic acid, hexafluorozirconic acid, and/or their anions.