| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a chemical conversion-treated Zn-based plated steel sheet having a chemical conversion-treated film including organic resins, and excellent in all of weatherability, water resistance, blackening resistance, film adhesion and processability. <P>SOLUTION: The chemical conversion-treated film having a thickness of 0.5-10 μm is formed by coating a chemical conversion treatment liquid on the surface of an Al-containing Zn-based alloy plated steel sheet and drying. The chemical conversion treatment liquid contains: a fluorine-containing resin including 0.05-5 mass% hydrophilic functional group and 7-20 mass% F atom and having a number-average molecular weight within the range from 1,000 to 2,000,000; any of oxyacid salts, fluorides, hydroxides, organic acid salts, carbonates or peroxide salts of group 4A metals; and resin particles having the average grain size of 0.1-10 μm. The amount of the above salts of group 4A metals relative to the fluorine-containing resin in the chemical conversion treatment liquid is within the range of 0.1-5 mass% in terms of metal. <P>COPYRIGHT: (C)2013,JPO&INPIT |
