Electrolytic bath and process for the deposition of gold alloy coatings

US4391679A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Wolfgang Zilske · Hanau, DE
• Werner Kuhn · Rodenbach, DE

Key dates

• Filing date: Apr 2, 1981
• Grant date: Jul 5, 1983
• Expiry date: Apr 2, 2001

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25D3/62
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

In the electro industry, there are needed acid gold alloy baths which give glossy, ductile coatings, operate at high current densities, and contain little non-metallic impurities. This is attained by a bath based on potassium cyanoaurate (III) and an acid whereby the bath contains at least one of the alloying metals cobalt, nickel, indium, tin, zinc, or cadmium in the form of a water soluble salt, together with an amine, an aminocarboxylic acid, or a phosphonic acid and has a pH of below 3.