No-rinse phosphating process

US5976272A · kind A · utility

Assignee

• Henkel Kommanditgesellschaft auf Aktien · DE

Inventors

• Reinhard Seidel · Windeck, DE
• Bernd Mayer · Graz, AT
• Melanie Joppen · Niederkrüchten, DE
• Melitta Krause · Goldkronach, DE
• Joerg Riesop · Niederzier, DE

Key dates

• Filing date: Mar 24, 1997
• Grant date: Nov 2, 1999
• Expiry date: Mar 24, 2017

Classification

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

Abstract

A process for phosphating metal surfaces by treatment with an acidic zinc- and phosphathe-containing solution which does not require rinsing. The metal substrate is contacted with a phosphating solution containing 2 to 25 g/l of zinc ions, 2 to 25 g/l of manganese ions and 50 to 300 g/l of phosphate ions. The solution has a pH value of 1 to 3.6, a free acid content of 0 to 100 points, a total acid content of 40 to 400 points and a ratio of free acid to total acid of 1:4 to 1:20.