Additive-free, fast precipitating palladium electrolyte bath and process

US4451336A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Frank Vangaever · Brugge, BE
• Jacky Vanhumbeeck · Brugge, BE
• Laurent Danneels · Varsenare, BE
• Luc Boone · Beernem, BE
• Luc Demaegd · Drongen, BE

Key dates

• Filing date: Nov 19, 1982
• Grant date: May 29, 1984
• Expiry date: Nov 19, 2002

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25D3/50
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

An additive-free, fast-precipitating electrolyte bath for precipitating lustrous, crack-free palladium layers on workpieces is formulated, by successively adding to distilled water heated up to about 90.degree. C., phosphoric acid, sufficient ammonia to neutralize the phosphoric acid and palladium, in the form of palladium chloride. After dissolution of the palladium salt, the operating pH value is adjusted by additions of ammonia or phosphoric acid as required and the volume of the bath can be increased as desired by additions of further distilled water. The bath can be filtered prior to use.