Abstract: An epoxy material that provides a cured product having a reduced modulus of elasticity and thereby maintaining reliability even under conditions of wide environmental variation. The epoxy resin composition provided includes (A) an epoxy compound A of formula (1) below, (B) phenyl glycidyl ether substituted with a C6-20 hydrocarbon group, and (C) a curing agent. In formula (1), R1 and R2 each independently represent C2-4 alkylene; R3 represents methylene or —C(CH3)2—; and a and b each independently represent a number of 1 to 10.

Abstract: Disclosed is a charge transfer complex capable of obtaining a curable resin composition having an excellent balance between curability and storage stability when used as an epoxy-resin curing agent. The charge transfer complex has an imidazole moiety as an electron donor moiety. The charge transfer complex may be an assembly wherein electrons included in a compound (a) having an imidazole moiety are accepted by a compound (b) having an electron acceptor moiety, or may be a compound having an imidazole moiety and an electron acceptor moiety in its molecule, and the electron acceptor moiety accepts electrons included in the imidazole moiety.