The production methodological null carbonic acid zirconium complex ion and the vanadyl ion of the plated steel which is superior corrosion-resistant

摘要

PROBLEM TO BE SOLVED: To provide plated steel with a chromate-free treated film, which has excellent corrosion resistance.;SOLUTION: In the plated steel, at least on side is provided with a corrosion resistant coated layer obtained by a treatment solution containing zirconium carbonate complex ions, vanadyl ions (VO²⁺) and oxycarboxylic acid, and containing, as the concentration in the solid contents, 10 to 30% zirconium, 5 to 20% vanadium, 20 to 50% oxycarboxylic acid, 0.01 to 1% meso-2,3- dimercaptosuccinic acid, and 0.01 to 1% ammonium phosphate by 200 to 1,200 mg/m² as the coating weight of a film. Preferably, the corrosion resistant coated layer contains a zirconium compound by 10 to 30% in terms of zirconium, a vanadyl compound by 5 to 20% in terms of vanadium, and meso-2,3- dimercaptosuccinic acid by 0.01 to 1%.;COPYRIGHT: (C)2003,JPO