摘要 |
PROBLEM TO BE SOLVED: To provide a surface treated steel sheet comprising no hexavalent chromium in a film and further capable of obtaining excellent corrosion resistance, flawing resistance, discoloration resistance and water resistance. SOLUTION: In the surface treated steel sheet, the surface of a galvanized steel sheet is provided with a surface treatment film formed of a surface treatment agent comprising a resin compound having a specified chemical structure, a cationic urethane resin having a quaternary ammonium base, a zinc compound, a zirconium compound, phosphoric acid or/and phosphate, and at least one acid compound selected from hydrofluoric acid, acetic acid, nitric acid, sulfuric acid and their salts in specified blending ratios, and the upper layer thereof is provided with an organic film comprising a specified resin composition, a specified rust prevention additional component(s) and a solid lubricant. COPYRIGHT: (C)2007,JPO&INPIT |