Process for producing modified alumina hydrate crystals

US4340579A · kind A · utility

Assignee

• Vereinigte Aluminum - Werke Aktiengesellschaft · DE

Inventors

• Jorg F. Greber · Bonn, DE
• Gunter Winkhaus · Rübhausen, DE

Key dates

• Filing date: Nov 30, 1979
• Grant date: Jul 20, 1982
• Expiry date: Nov 30, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/22
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a modified form of alumina hydrate filler, thermosetting and thermoplastic compositions having improved workability and mechanical properties containing such filler and methods of manufacturing such modified alumina hydrate filler. More specifically, the invention provides for the admixture of modified alumina hydrate crystals with a resinous composition in which the individual alumina hydrate crystal edges are substantially rounded, have a mean crystal size of less than about 35 microns and less than about 0.1% by volume of alumina hydrate crystals have a diameter of less than 2 microns. The resulting compositions have improved viscosity properties and exhibit good bending strength and flame retardant characteristics.