| 摘要 |
PROBLEM TO BE SOLVED: To produce the subject resin which is useful as an adhesive, an adhesive film, etc., for electronic materials and has hitherto been difficult to synthesize by reacting a phenolic novolak type epoxy resin having a softening point within a specific temperature range with a bifunctional phenol compound. SOLUTION: This epoxy resin is obtained by providing a phenolic novolak skeleton as a main skeleton and has >=75 deg.C softening point. The epoxy resin is prepared by reacting a phenolic novolak type epoxy resin having 50-72 deg.C softening point with a bifunctional phenol compound in an amount of (1/25) to (1/40) equivalent by using preferably phosphines as a catalyst, preferably in the presence of an organic solvent. The content of the phosphines in the resultant epoxy resin is preferably <=500 ppm. The epoxy resin can be used by mixing thereof with an organic solvent or providing an epoxy resin solution synthesized by using the organic solvent in the same manner as described above as a varnish, etc., for laminates.
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