| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface-treated steel sheet for can manufacturing which is excellent in the content resistance after working by successively forming a first layer of a nickel-diffusion layer or a tin-diffusion layer through the heat treatment of the prescribed quantity, a second layer containing metallic chromium of the prescribed quantity, and a third layer containing chromium hydrated oxide of the prescribed quantity on the surface of the steel sheet. SOLUTION: The electrolytic cleaning is achieved on a cold-rolled steel sheet. After the nickel plating or tin plating of 1000-50000 mg/m<2> is achieved on the surface of the steel sheet, the heat treatment of 520-750 deg.C and 10-300 seconds is performed in the non-oxidizing atmosphere. A heat diffusion layer containing approximately >=95% of the plated nickel or tin is formed on the surface of the steel sheet. After a nickel plated layer of 500-5000 mg/m<2> as necessary is provided on the nickel diffusion layer or the tin diffusion layer, a metallic chromium layer of 50-300 mg/m<2> and a chromium hydrated oxide layer of 5-50 mg/m2 are precipitated through the electrolytic chromic acid treatment, etc. Then, the polyester resin is covered over at least one side of the surface-treated steel sheet with excellent adhesibility as necessary. |
