摘要 |
An additive for an alkaline zinc or zinc alloy electroplating bath medium, the additive comprising a random co-polymer comprising the reaction product of: (i) one or more di-tertiary amines including an amide or thioamide functional group, and (ii) optionally, one or more saturated second di-tertiary amines and/or one or more second di-tertiary amines including an unsaturated moiety, with (iii) one or more saturated or unsaturated linking agents capable of reacting with said di-tertiary amines (i) and (ii), provided that, where all the linking agents are saturated, an unsaturated di-tertiary amine must he present. Preferably, the polymer has the general formula n(2x+2y+zE<SUB>p</SUB>)j-. |