Preparation of particularly bluish pearl luster pigments

US4948631A · kind A · utility

Assignee

• BASF SE

Inventors

• Werner Ostertag · Havelsee, DE
• Norbert Mronga · Dossenheim, DE
• Ulrich Graessle · Haßloch, DE

Key dates

• Filing date: Mar 9, 1989
• Grant date: Aug 14, 1990
• Expiry date: Mar 9, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09C2220/20
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Particularly bluish pearl luster pigments are produced by treating titanium dioxide coated mica pigments where the optical thickness of the titanium dioxide coating is from 50 to 100 nm or from 300 to 340 nm with ammonia at from 750 to 850.degree. C. with constant agitation.