Method for treatment of a chromium finish surface

US11078585B2 · kind B2 · utility

Assignee

• Atotech Deutschland GmbH & Co. KG · DE

Inventors

• Christina Pfirrmann · Berlin, DE
• Berkem ÖZKAYA · Berlin, DE
• Philipp Wachter · Berlin, DE
• Nancy Born · Berlin, DE

Key dates

• Filing date: Sep 26, 2017
• Grant date: Aug 3, 2021
• Expiry date: Sep 18, 2038

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25D9/06
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A method for post-treatment of a chromium finish surface to improve corrosion resistance comprising a) providing a substrate having a chromium finish surface, and at least one intermediate layer between the chromium finish surface and the substrate, selected from the group consisting of nickel, nickel alloys, copper and copper alloys, wherein the chromium finish surface is a surface of a trivalent chromium plated layer, obtained by electroplating the substrate, having the at least one intermediate layer, in a plating bath, the plating bath comprising chromium (III) ions; b) contacting the chromium finish surface with an aqueous solution, comprising a permanganate, at least one compound which is selected from a phosphorus-oxygen compound, a hydroxide, a nitrate, a borate, boric acid, a silicate, or a mixture of two or more of these compounds; c) forming a transparent corrosion protection layer onto the chromium finish surface during step b.