Aqueous solution and method for phosphatizing metallic surfaces

US6497771B1 · kind B1 · utility

Assignee

• Metallgesellschaft AG · DE

Inventors

• Peter Schubach · Nidderau, DE
• Joachim Heitbaum · Bad Homburg vor der Höhe, DE
• Thomas Kolberg · Heppenheim, DE
• Margit Fleischhacker-Jeworrek · Usingen, DE
• Peter Jorns · Frankfurt am Main, DE
• Michael Deemer · Frankfurt am Main, DE
• Ralf Stickler · Kahl am Main, DE
• Jurgen Specht · Rodgau, DE
• Michael Lenhard · Bad Vilbel, DE

Key dates

• Filing date: Jan 9, 2001
• Grant date: Dec 24, 2002
• Expiry date: Jan 9, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23C22/365
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

An aqueous solution contains phosphate for producing layers of phosphate on metal surfaces selected from the group consisting of iron, steel, zinc, zinc alloys, aluminum and aluminum alloys. The solution contains 0.3 to 5 g Zn2+/1, 0.1 to 2 g nitroguanidine/1 and 0.05 to 0.5 g hydroxylamine/l, with an S-value amounting to 0.03 to 0.3 and the ratio of the weight of Zn2+ to P2O5=1:5 to 1.30.