| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface-treated steel sheet which is suitable to an Al-Zn-based alloy plated steel sheet used under non-coating in the use for building materials and the field of household electric appliances, mainly used in the outdoor environment, and contains no chromium in a film. SOLUTION: Regarding the surface-treated steel sheet, the surface of an Al-Zn-based alloy plating film is provided with a first surface treatment layer formed by applying a surface treatment composition comprising a titanium-containing liquid obtained by mixing at least one titanium compound selected from a hydrolyzable titanium compound, a low condensate of a hydrolyzable titanium compound, titanium hydroxide and a low condensate of titanium hydroxide with a hydrogen peroxide solution; a nickel compound; an aluminum compound; a fluorine-containing compound; and a silane compound, and drying the same, and the surface of the first surface treatment layer is provided with a second surface treatment layer formed by applying a surface treatment composition comprising a copolymerized resin obtained from: acrylic acid and/or methacrylic acid; acrylic acid ester and/or methacrylic acid ester having an alkyl chain of the carbon number of 1 to 6; and vinyl monomers copolymerizable with the acrylic acid and/or methacrylic acid and the acrylic acid ester and/or methacrylic acid ester, and drying the same. COPYRIGHT: (C)2010,JPO&INPIT |
