Epoxy resin composition, cured article thereof, semiconductor sealing material, novel phenol resin, novel epoxy resin, method for producing novel phenol resin, and method for producing novel epoxy resin

An epoxy resin composition comprising an epoxy resin and a curing agent as essential components,

• wherein the epoxy resin has each structure of a glycidyloxy group-containing aromatic hydrocarbon group (E), an alkoxy group-containing aromatic hydrocarbon group (B) and a divalent aralkyl group (X), and also has, in a molecular structure, a structure in which the glycidyloxy group-containing aromatic hydrocarbon group (E) and the alkoxy group-containing aromatic hydrocarbon group (B) are bonded to another glycidyloxy group-containing aromatic hydrocarbon group (E) or alkoxy group-containing aromatic hydrocarbon group (B) via the divalent aralkyl group (X),
• wherein the alkoxy group-containing aromatic hydrocarbon group (B) is a divalent or trivalent aromatic hydrocarbon group formed from a molecular structure selected from methoxybenzene, methoxynaphthalene, ethoxybenzene, ethoxynaphthalene, and a compound having a methyl group as a substituent on the aromatic nucleus of them,
• wherein the divalent aralkyl group (X) is a divalent hydrocarbon group having a structure represented by the following structural formula (1):
• wherein R1 represents a hydrogen atom or a methyl group, and Ar represents a phenylene group, a biphenylene group or a diphenyl ether-4,4′-diyl group, and
• wherein the glycidyloxy group-containing aromatic hydrocarbon group (E) is a divalent or trivalent aromatic hydrocarbon group formed from a molecular structure selected from glycidyloxybenzene, glycidyloxynaphthalene, and a compound having a methyl group as a substituent on the aromatic nucleus of them.