Abstract: Spherical fused silica with an average particle diameter within the range of 10 to 50 .mu.m and having a particle size distribution of 1 to 100 .mu.m in diameter is a useful filler for resin compositions having improved mechanical and electrical properties as well as good flowability and low viscosity. The spherical fused silica is preferably treated on its surface with a silane coupling agent. Resin compositions containing said spherical fused silica as the major filler are particularly useful as casting materials.

Abstract: One-component epoxy resin coating materials comprising(A) an epoxy resin or a mixture of epoxy resins,(B) as hardener for the epoxy resin at least one aromatic dicarboxylic acid dihydrazide or a triazine compound of the formula I ##STR1## (R=alkylamino or dialkylamino having 1 or 2 carbon atoms in the alkyl moieties, phenylamino or hydrazino) and(C) an anti-sagging agent or an inorganic filler or a mixture of anti-sagging agent and an inorganic filler, are used for the coating of fixed resistors. The resultant coatings exhibit good heat, moisture and cracking resistance.