| abstract |
(57) [Abstract] [Purpose] Epoxy resin prepolymer is made into a varnish by using an alcohol solvent as a solvent, and odor control at the time of manufacturing a laminated board is inexpensive and unnecessary. [Structure] A bifunctional epoxy resin selected from a bifunctional epoxy resin having an epoxy equivalent of 250 or less and a brominated bifunctional epoxy resin having an epoxy equivalent of 500 or less, and a polyfunctional phenol having more than 2 phenolic hydroxyl groups in one molecule. Reaction in an alcoholic solvent in the presence of a catalyst, based on 1 equivalent of epoxy resin, 0.05 to 0.6 equivalents of phenols, solid concentration of 30 to 95%, temperature of 50 to 130 ° C, and inert atmosphere. Let |