Highly filled epoxy casting resin compositions

US5552459A · kind A · utility

Assignee

• Ciba-Geigy · US

Inventors

• Dieter Baumann · Greven, DE
• Werner Hollstein · Schliengen, DE
• Claus W. Rabener · Wedel, DE
• Peter R uger · Oberwil, CH

Key dates

• Filing date: May 10, 1994
• Grant date: Sep 3, 1996
• Expiry date: May 10, 2014

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08K3/22
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to flame-retarded compositions comprising A) an epoxy resin mixture consisting of PA1 A1) 15-35% by weight of at least one liquid epoxy resin, PA1 A2) 55-85% by weight of aluminum oxide trihydrate having a particle size of D.sub.50 20-25 .mu.m as determined by sieving, PA1 A3) 0-20% by weight of at least one further filler and PA1 A4) 0-5% by weight of at least one conventional additive and B) at least one carboxylic acid anhydride or PA1 a cycloaliphatic diamine of the formula I or II ##STR1## in which the radicals R.sub.1 to R.sub.4 independently of one another are hydrogen or C.sub.1 -C.sub.4 alkyl and Z is a direct bond, --CH.sub.2 --, --C(CH.sub.3).sub.2 --, --S--, --O--, --SO.sub.2 -- or --CO--, in an amount sufficient to cure component A, the content of components A2 and A3 together being 63-80% by weight, with respect to the total weight of the composition. These compositions are suitable for use in high voltage components, such as flyback transformers.