Process for phosphating metals

US4637838A · kind A · utility

Assignee

• Metallgesellschaft AG · DE

Inventors

• Werner Rausch · Hopewell Junction, US
• Gerhard Mueller · Freilassing, DE

Key dates

• Filing date: Mar 5, 1985
• Grant date: Jan 20, 1987
• Expiry date: Mar 5, 2005

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23C22/362
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

The quality of coatings in a low zinc phosphating process is improved by including an activator of formate, nitrilotriacetate, trichloroacetate or ethylenediamenetetraacetate to produce more uniform coatings particularly desirable in advance of electrocoating.