Biege-brown encapsulated pigments and method of their production

US5035746A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Dietrich Speer · Hanau, DE
• Akos Kiss · Alzenau, DE
• Peter Kleinschmit · Hanau, DE

Key dates

• Filing date: Mar 2, 1990
• Grant date: Jul 30, 1991
• Expiry date: Mar 2, 2010

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2002/52
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Beige-brown encapsulated pigments are obtained by means of the encapsulation of iron titanates of the formula Fe.sub.2 TiO.sub.5 in zirconium silicate crystals. The production takes place by calcining a mixture of zirconium oxide with a particle size distribution of .ltoreq.5 .mu.m and specific surfaces of .gtoreq.4 m.sup.2 /g, silicon dioxide and iron oxides and titanium oxides or oxide-forming Fe compounds and Ti compounds in the presence of mineralizers under oxidizing conditions at 800.degree. to 1300.degree. C.