Patent · US Active

Essentially chromium-free method for passivating metallic surfaces consisting of Zn, Zn alloys, Al or Al alloys

US8241745B2 · kind B2 · utility

0Cited by

8References

18Claims

0Family size

Assignee

BASF SE

Inventors

Frank Dietsche · Schriesheim, DE
Frank Klippel · Ludwigshafen, DE
Matthias Kluglein · Ludwigshafen, DE
Alexander Gothlich · Mannheim, DE

Key dates

Filing date	Oct 15, 2004
Grant date	Aug 14, 2012
Priority date	—
Expiry date	Dec 25, 2026

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T428/31692
WIPO fieldSurface technology, coating
WIPO sectorChemistry

Abstract

The present invention relates to a substantially chromium-free process for passivating metallic surfaces of Zn, Zn alloys, Al or Al alloys by treating the surface with an acidic aqueous formulation which comprises at least one substantially noncrosslinked, water-soluble polymer or copolymer containing at least 50% by weight of (meth)acrylic acid units and comprises water or an aqueous solvent mixture comprising at least 50% by weight of water, and by further treating the surface with at least one water-soluble crosslinker comprising at least 2 crosslinking groups selected from the group consisting of azirane, oxirane, and thiirane groups. The invention further relates to passivating layers obtainable by means of the process and to a formulation suitable for this process.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.