| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a surface-treated steel sheet which is excellent in corrosion resistance in spite of containing no Cr and can attain excellent wet resin adhesion even when laminated with a resin film under conditions which favor a heightened BO value of the resin film. SOLUTION: There is provided a method for producing a surface-treated steel sheet comprising forming a corrosion-resistant film consisting of at least one layer selected from among an Ni layer, an Sn layer, an Fe-Ni alloy layer, an Fe-Sn alloy layer, and an Fe-Ni-Sn alloy layer on the surface of a steel sheet and further forming an adhesive film by subjecting the resultant steel sheet to a cathode electrolysis in an aqueous solution containing 0.008-0.07 mol/l of Ti and further containing, in total, 0.01-10 (a molar ratio to the Ti) of at least one member selected from among Co, Fe, Ni, V, Cu, Mn, and Zn by using an electric current which has a current density changing at a cycle time of 0.01-0.4 sec between the current density (current density 1) at which Ti deposits and the current density (current density 2) at which Ti does not deposit and has a time duration during which it stays at the current density 2 per cycle is 0.005-0.2 sec under conditions in which the cycle is 10 or more, and the total electric quantity density at the current density 1 is 4 C/dm<SP POS="POST">2</SP>or more, wherein the upper limit of the current density 2 depends on the composition and the pH of the aqueous solution used in the cathode electrolysis. COPYRIGHT: (C)2012,JPO&INPIT |
