Henkel Kommanditgesellschaft Auf Aktien

Henkel Ag & Company, Kgaa

Annette Willer

Jan-Willem Brouwer

Bernd Mayer

Juergen Geke

William E Fristad

Horst-Dieter Speckmann

Peter Kuhm

Jens Kroemer

Jens Krömer

Thomas Molz

Markus Senner

Pietro Balboni

Melita Krause

Karl-Dieter Brands, Deceased

The present invention relates to an aqueous alkaline composition (A) for alkaline passivation of metallic components comprising at least in part surfaces of zinc or zinc alloys, containing iron(III) ions, phosphate ions, and one or more complexing agents, where a free alkalinity ranges from 1 to 6 points, and the pH is at least 11. The aqueous compositions (A) can additionally contain nonionic surfactants, so that such compositions are suitable for use in a method in which both cleaning and alkaline passivation of the metallic component occur in one step. The present invention further relates to a method for alkaline passivation of metallic components by contacting them with composition (A), and further a method for surface treatment in automobile body production, in which the alkaline passivation step using composition (A) is followed by an acid passivation step using a composition (B).

Composition for the alkaline passivation of zinc surfaces

An acidic aqueous phosphating solution is presented having 0.2 to 3 g/l of zinc ions, 3 to 50 g/l of phosphate ions expressed as PO , and 0.05 to 4 g/l of an organic N-oxide containing a saturated, unsaturated or aromatic 5- or 6-membered ring system, where the N atom of the N-oxide is part of said ring system, and where the ratio by weight of phosphate ions to zinc ions is from 3.7 to 30:1. The solution is free of hydroxylamine and useful in phosphating metal surfaces.

Phosphating method accelerated by N-oxides

Iron phosphating using substituted monocarboxylic acids

Growing community of inventors

Neuss, Germany

Annette Willer