| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a colored or galvanized steel colored into black or gray even if blackening alloy elements are not contained as essential components and excellent in the adhesion of a colored film. SOLUTION: This colored zinc or galvanized steel excellent in film adhesion is the one in which a colored film essentially consisting a copper compd., a chromic acid compd. and a phosphoric acid compd., and in which the contents (mg/m<2> ) of Cu, Cr and P satisfy O<Cu-Cr-P <=300 is formed on the surface of a zinc or galvanized steel. This steel contains <=30 wt.% black pigment in a film B2 on the colored film B1. In the method for producing the colored zinc or galvanized steel, a zinc or galvanized steel is dipped into an aqueous soln. having a compsn. essentially consisting of copper ions, sexivalent chromium ions and phosphoric acid ions and satisfying the concn. of copper ions/the concn. of sexivalent chromium ions >1.6 and 1.5 <= the concn. of phosphoric acid/the total chromium concn. <=3.0.</p> |
