Process for preparing rutile-coated mica pigments

US4867794A · kind A · utility

Assignee

• Merck Patent GmbH · DE

Inventors

• Klaus Ambrosius · Frankfurt, DE
• August Knapp · Dieburg, DE
• Helmut Plamper · Dieburg, DE
• Reiner Esselborn · Darmstadt, DE

Key dates

• Filing date: Dec 11, 1987
• Grant date: Sep 19, 1989
• Expiry date: Dec 11, 2007

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09C2220/106
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

In mica/titanium dioxide pigments reliable rutilization is obtained with small amounts of tin by precipitating tin dioxide directly on the mica and completing this precipitation before the precipitation of titanium dioxide is started.