Patent ID: 11913131
Assignee: MACDERMID, INCORPORATED
Field: Surface technology, coating (Chemistry)
Classification: CPC C  B  H | IPC B  C  H

Claim 0:
1. An aqueous alkaline zinc-nickel-iron electroplating bath for depositing a ternary zinc-nickel-iron alloy on a substrate, the aqueous alkaline zinc-nickel-iron electroplating bath comprising:
zinc ions,
nickel ions,
an alkaline compound selected from the group consisting of sodium hydroxide and potassium hydroxide, and
a complex consisting of an iron salt and an iron complexing agent, wherein the iron complexing agent is selected from the group consisting of sodium gluconate, sodium tartrate, sodium hydroxybutyrate, potassium gluconate, potassium tartrate, and/or potassium hydroxybutyrate, and wherein the complex is formed prior to addition to the electroplating bath,
wherein a concentration of iron ions in the electroplating bath provided by the complex is from about 0.1 gram per liter to about 25 grams per liter,
wherein the electroplating bath is maintained at a pH of more than about 13
wherein the electroplating bath is configured to deposit a ternary zinc-nickel-iron alloy containing 7 to 16 wt. % nickel, 0.5 to 8.0 wt. % iron, and the balance zinc, and
wherein the electroplating bath is at least essentially free of iron hydroxide.