Aqueous dispersion containing pyrogenically prepared metal oxide particles and dispersants

US7470423B2 · kind B2 · utility

Assignees

• Degussa AG · DE
• GOLDSCHMIDT HOLDING GMBH · DE

Inventors

• Wolfgang Lortz · Wächtersbach, DE
• Christoph Batz-Sohn · Hanau, DE
• Steffen Hasenzahl · Hanau, DE
• Gabriele Perlet · Großkrotzenburg, DE
• Werner Will · Gelnhausen, DE
• Ralf Mathiak · Gladbeck, DE
• Klaus Jenni · Witten, DE

Key dates

• Filing date: May 14, 2003
• Grant date: Dec 30, 2008
• Expiry date: Dec 16, 2024

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2004/64
• WIPO field: Pharmaceuticals
• WIPO sector: Chemistry

Abstract

An aqueous dispersion containing pyrogenically prepared oxide particles of titanium, zinc, iron or cerium with an average particle size, expressed as the median, in the dispersion of less than 250 nm, that the particle sizes of the oxide particles in the dispersion are not distributed symmetrically and the dispersion contains, as a dispersant, at least one compound of the formula (I) and/or a maleic anhydride/acrylate copolymer of the general formula (IIa) and/or a maleate/acrylate copolymer of the general formula (IIb). It is prepared by dispersing a predispersion stream by means of a high energy mill. It can be used in sunscreen formulations.