Color pure iron oxide pigments, a process for their preparation and their use

US5049195A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Wilfried Burow · Krefeld, DE
• Hans-Ulrich Hofs · Krefeld, DE
• Karl-Werner Ganter · Krefeld, DE
• Gerd-Hermann Schulten · Duisburg, DE

Key dates

• Filing date: Nov 22, 1989
• Grant date: Sep 17, 1991
• Expiry date: Nov 22, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/60
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Red iron oxide pigments having a lower metal impurity content and enhanced purity of color are disclosed as being comprised of clusters of spherical particles.