| abstract |
(57) [Summary] [Structure] 3,3 ', 5,5'-Tetramethylbiphenol diglycidyl ether, a melt mixture of a flexible phenol resin curing agent of the following formula and tetraphenylphosphonium tetraphenylborate and a melt An epoxy resin composition comprising silica powder. [Chemical 1] [Effects] Improvements in moldability and curability, which could not be obtained with conventional technology, can be achieved, and it is extremely excellent in crack resistance when subjected to thermal stress due to rapid temperature changes in the soldering process. Is good. |