Patent ID: 8329019

Claim:
A zinc or zinc alloy electroplating bath comprising: zinc ions and a brightening agent, the brightening agent comprising at least one polyamine or a mixture of polyamines, the at least one polyamine or mixture of polyamines including a first repeating unit that has the general formula: and a second repeating unit having the general formula: where Δ 1 is O, N, or S; x is an integer from 2 to 6; y is an integer from 1 to 6; R 1 , R 2 , R 3 , and R 4 , which is the same or different, is methyl, ethyl, isopropyl, n-propyl, hydroxyethyl, or —CH 2 CH 2 (OCH 2 CH 2 ) m OH; m is a number between 0-6; R 5 represents a group of atoms necessary to complete a heterocyclic compound having a five or six membered ring containing at least two nitrogen atoms; and R 6 is nothing or an alkyl group, wherein the first repeating unit and the second repeating unit are in the same polymer chain.