MICROCAPSULE TYPE PHOSPHOROUS CURING ACCELERATOR AND EPOXY RESIN COMPOSITION USING THE SAME AND USED FOR SEALING SEMICONDUCTOR

摘要

PROBLEM TO BE SOLVED: To obtain the subject curing accelerator having excellent storage stability and molding curability and useful as a sealing material for semiconductors by coating cores comprising a specific curing accelerator with a shell resin. SOLUTION: This curing accelerator is obtained by coating (A) cores comprising a phosphorous curing accelerator with (B) a shell resin. The component A preferably contains the phosphobetaine of a triorganophosphine of the formula [R is a 1-4C alkyl or the like; (m) is an integer of 0, 1, 2 or 3]. The component B is preferably a thermosetting resin or a thermoplastic resin having a melting point or softening point of >=40 deg.C. The component A is preferably contained in an amount of 5-90 wt.% in the curing accelerator. The curing accelerator may be obtained by grinding the kneaded product of the components A and B, classifying the ground products into a class having a prescribed volume- average particle diameter, and subsequently treating the class with a specific device to stick and fuse the fine particles of the component B to the surfaces of the component A.