摘要 |
A galvanization bath additive, which comprises a copolymer of (A) urea, (B) N,N-dimethyl ethylenediamine, (C) N,N,N',N'-tetraalkyl alkylenediamine, and (D) at least one of dichloroalkylether, dichloroalkane and epichlorohydrin, is added to a galvanization bath comprising 1-50 g/L of zinc and 30-250 g/L of sodium hydroxide. As a result, the plating film formation rate is increased and it is possible to prevent abnormal deposition at high current density. |