| 摘要 |
The object of the present invention is to provide a process for producing a metal substrate of superior corrosion resistance and finish, and a surface-treated metal substrate obtained by the process; and a surface treatment process that is capable of providing a metal substrate of superior corrosion resistance and finish, and a surface-treated metal substrate obtained by the process. Specifically, the present invention provides a process for producing a surface-treated metal substrate, comprising the steps of immersing a metal substrate for use as a cathode in a treatment composition (I) comprising water and metal component (A), and applying electric current thereto for 10 to 600 seconds by superposing an AC voltage (Va) with a frequency of 0.1 to 1,000 Hz and a peak-to-peak voltage of 1 to 40 V onto a 1 to 50 V DC voltage (Vd). |
