Preparation of magnetite pigments: control of particle size

US4702775A · kind A · utility

Assignee

• BASF SE

Inventors

• Werner Ostertag · Havelsee, DE
• Henning Wienand · Neulußheim, DE
• Roland Bauer · West Milford, US

Key dates

• Filing date: Jun 25, 1986
• Grant date: Oct 27, 1987
• Expiry date: Jun 25, 2006

Classification

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

Abstract

Magnetite pigments are prepared from iron(II) salt solutions by a process in which the mean particle size can be brought to a value within the range from 0.06 to 0.5 .mu.m by means of a residence stage between the precipitation stage and the oxidation stage.