Vinylbenzylated phenol compound, method of manufacturing vinylbenzylated phenol compound, activated ester resin, method of manufacturing activated ester resin, thermoset resin composition, hardened material of thermoset resin composition, interlayer insulating material, prepreg, and method of manufacturing prepreg

An active ester resin comprising a component represented by General Formula (6) below,

• where, in General Formula (6), X is a structure represented by General Formula (7), General Formula (8) or General Formula (13) below, Ar1 and Ar2 may be the same or different and are each a phenyl group, a phenyl group having one to three alkyl groups each with one to four carbon atoms on an aromatic nucleus, a naphthyl group, or a naphthyl group having one to three alkyl groups each with one to four carbon atoms on an aromatic nucleus, and an average number of repetition n is 0.5 to 30,
• where, in General Formula (7) and General Formula (8), R1 to R15 may be the same or different and are each hydrogen or a methyl group, an average number of repetition m is 0.1 to 4, and an average number of repetition 1 and an average number of repetition k are each independently 0.1 to 2, and Y in General Formula (8) is a direct bond, —CH2—, —C(CH3)2—, —CH(CH3)—, an ether bond, a fluorenyl group, a sulfone group, a cyclohexylidene group, a 3,3,5-trimethylcyclohexylidene group, —C(CF3)2—, or —C(CH3)(Ph)-;
• or a structure represented by General Formula (21), General Formula (22) or General Formula (23) below.
• (R26 to R33 may be the same or different and are each hydrogen or a methyl group.)
• (Z in General Formula (13) is a direct bond, —CH2—, —C(CH3)2—, —CH(CH3)— —CH(Ph)-, —C(CH3)(Ph)-, a fluorenyl group, a cyclohexylidene group, or a 3,3,5-trimethylcyclohexylidene group;
• or a structure represented by General Formula (21), General Formula (22) or General Formula (23) above, and R16 to R25 may be the same or different and are each hydrogen or a methyl group, and average numbers of repetition j and I are each independently 0.1 to 2.)