Copper-tin electrolyte and method for depositing bronze layers

US8211285B2 · kind B2 · utility

Assignee

• Umicore Galvanotechnik GmbH · DE

Inventors

• Klaus Bronder · Tegernsee, DE
• Bernd Weyhmueller · Hintersteinenberg, DE
• Frank Oberst · Schwäbisch Gmünd, DE
• Sascha Berger · Schwäbisch Gmünd, DE
• Michael Lauster · Schwäbisch Gmünd, DE

Key dates

• Filing date: Jan 24, 2008
• Grant date: Jul 3, 2012
• Expiry date: Apr 2, 2028

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25D3/58
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Consumer goods and industrial articles are electro-plated with bronze layers for decorative reasons and to protect them against corrosion. The electrolytes used hitherto for producing decorative bronze layers are either cyanide-containing or, as in the case of baths based on organosulphonic acids, highly corrosive or have, as in the case of cyanide-free baths based on diphosphoric acid, unsatisfactory long-term stabilities. Electrolytes which are used for applying solderable bronze layers in the electronics industry usually contain toxic or very toxic thio compounds. The present invention provides a non-toxic electrolyte which displays long-term stability for the electrolytic deposition of decorative bronze layers and a corresponding process for the application of such decorative bronze layers to consumer goods and industrial articles.