| abstract |
The present invention is the method for surface treatment of a metal material containing iron and/or zinc, comprising component (A) and component (B); n (A) a compound containing at least one metal element selected from the group consisting of Ti, Zr, Hf and Si, n (B) a compound containing fluorine as a supplying source of HF, wherein, ratio K=A/B between total mole weight A of metal elements of Ti, Zr, Hf and Si in the compound of component (A) and mole weight B which when total fluorine atom in fluorine containing compound of component (B) is converted to HF is within the range of 0.06≦K≦0.18, and the concentration of component (A) indicated by the total mole concentration of metal elements of Ti, Zr, Hf and Si is within the region of 0.05 to 100 m mol/L. To the treating solution for surface treatment, at least one compound containing at least one metal element selected from the group consisting of Ag, Al, Cu, Fe, Mn, Mg, Ni, Co and Zn can be blended. n It is possible to form a surface treated film which is superior at corrosion resistance after coated on the surface of a metal containing iron or zinc, in the solution which does not contain harmful component to the environmental. |