| 摘要 |
PROBLEM TO BE SOLVED: To obtain a surface treated steel sheet which does not substantially comprise hexavalent chromium in a sealing treatment film, and has excellent corrosion resistance and coating material adhesion as well. SOLUTION: The surface of a galvanized steel sheet is provided with a phosphate film of a prescribed coating weight. The upper layer is provided with a chromate film in which the coating weight of chromium (expressed in terms of metal chromium) is 2 to 30 mg/m<SP>2</SP>, and formed by performing cathode electrolytic treatment in a chromate treatment liquid comprising hexavalent chromium and the subsequent water washing. The surface treated steel sheet does not substantially comprise hexavalent chromium in the chromate film, and exhibits excellent corrosion resistance and coating material adhesiveness. COPYRIGHT: (C)2004,JPO
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