Surface treatment liquid for a zinc-based metal material and method for surface treatment of a zinc-based metal material

摘要

A surface treatment liquid whose pH is from 2 to 5 for a zinc-based metal material comprising the following components (A) and (B): (A) at least one metal element selected from the group consisting of Ti, Zr and Hf; (B) at least one imino compound selected from 2-propanimine, 1,2-ethanediimine, N-methyl-ethanimine, ethyleneimine, polyethyleneimine, propyleneimine and polypropyleneimine; (C) fluorine and (D) at least one metallic element selected from the group consisting of Mg, Al, Zn, Cu and Co, in which the total concentration of the metallic elements of said component (A) is 500 to 2,000 mg / l, the total concentration of the compounds of said component (B) is 300 to 3,000 mg / l and the total concentration of the metallic elements of said component (D) is 500 to 10,000 mg / l.