| abstract |
An active ester resin having a low hardening shrinkage, excellent dielectric properties in a cured product, and high solvent solubility, a curable resin composition containing the same, a cured product thereof, a printed wiring board and a semiconductor encapsulating material. A novolak resin having a naphthol compound (a) as a reaction raw material, which comprises a novolak resin (A) containing a component having a nuclear number of 3 or more as an essential component, a compound (B) having a phenolic hydroxyl group in the molecule, And an aromatic polycarboxylic acid or an acid halide thereof (C) as an essential reaction raw material. |