| 摘要 |
PROBLEM TO BE SOLVED: To provide a cresol novolak resin having a narrow molecular weight distribution and a reduced amount of a binucleate component which can form a coating film having excellent curability when used as the curing agent for epoxy resin based coating materials. SOLUTION: The cresol novolak resin composition for coating materials is obtained by reacting cresols composed of o-cresol and p-cresol with formaldehyde in the presence of an acidic catalyst, and has a bonding ratio of the o- cresol to the p-cresol in the resin, obtained by the NMR measurement, of 1/9 to 7/3, a bonding molar number of the formaldehyde per mole cresol component of 0.7-0.95 mole, a content of a binuleate component, obtained by the GPC measurement, of <=6%, a number average molecular weight of 600-3,000 and, simultaneously, a degree of dispersion (a ratio of the weight average molecular weight to the number average molecular weight) of <=3.2.
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