An electrical encapsulation composition is disclosed comprising (a) an epoxy resin which is the product of glycidating a polyphenolic compound which is the condensation product of (i) a substituted phenol which can be represented by the formula ##STR1## in which each R is selected independently from hydrogen, C.sub.1-5 alkyl and phenyl, with the provisos that at least two R groups are not hydrogen and that the R groups may be bonded in a ring structure, and (ii) an aromatic aldehyde or aromatic ketone having a phenolic hydroxyl group as represented by the general formula ##STR2## in which R' is selected from hydrogen, C.sub.1-5 alkyl and phenyl, R" is selected from C.sub.1-5 alkyl, phenyl, methoxy and halogen, and n is an integer from 0 to 4; (b) a curing agent for the epoxy resin; and (c) an inorganic filler.