Weathering-resistant pearlescent pigments

US4544415A · kind A · utility

Assignee

• Merck Patent GmbH · DE

Inventors

• Klaus-Dieter Franz · Kelkheim, DE
• Manfred Kieser · Darmstadt, DE
• Otto Stahlecker · Darmstadt, DE

Key dates

• Filing date: Sep 21, 1984
• Grant date: Oct 1, 1985
• Expiry date: Sep 21, 2004

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2998
• WIPO field: Pharmaceuticals
• WIPO sector: Chemistry

Abstract

Pearlescent pigments having improved weathering resistance are based on mica flakes coated with metal oxides, these pigments possessing on top of the coat of metal oxide a topcoat which contains a polysiloxane and a rare earth metal compound.