| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a molded product of a Zn-based alloy plated steel sheet having a chemical conversion coating, capable of forming a chemical conversion coating excellent in weather resistance, water resistance and coating adhesion even when a post coat method is used. <P>SOLUTION: In this method for manufacturing the molded product, the chemical conversion treatment liquid is coated on the surface of the molded product made of an Al-containing Zn-based alloy plated steel sheet and is dried to form the chemical conversion coating having a film thickness of 0.5-10 μm. The chemical conversion treatment liquid contains: an emulsion of a fluorine-containing resin with an average particle size of 50-300 nm; and an oxysalt of a Group 4A metal, fluoride, hydroxide, an organic acid salt, carbonate or a peroxide salt. The fluorine-containing resin contains 0.05-5 mass% of hydrophilic functional groups selected from the group consisting of a carboxyl group, a sulfonic acid group and the salts thereof, and 7-20 mass% of F atoms, and has a number average molecular weight within the range of 1,000-2,000,000. <P>COPYRIGHT: (C)2012,JPO&INPIT |
