| abstract |
[PROBLEMS] To provide a curable epoxy resin composition capable of forming a cured product having high heat resistance, light resistance, and thermal shock resistance, and particularly capable of improving moisture absorption reflow resistance of an optical semiconductor device. An epoxy compound (A), an acid anhydride curing agent (B), a silane coupling agent (C) having a thiol group, and a curing accelerator (D) represented by the formula (1) And a curable epoxy resin composition. [R 1 is independently a C1-10 alkyl group; R 2 is a C1-4 alkyl group; X − is a conjugate base of a carboxylic acid] [Selection figure] None |