| 摘要 |
PURPOSE:To obtain the titled resin having improved fluidity, by adding a specific amount of an ammonium halide to a reaction system having a specific conversion of aldehyde and a specific water-content in the reaction of a phenolic compound with an aldehyde in the presence of an acidic catalyst. CONSTITUTION:A phenolic resin having improved fluidity and curability and suitable as a shell mold, etc., is produced by adding an ammonium halide (preferably ammonium chloride and/or ammonium bromide) to a reaction system having an aldehyde conversion of >=90wt% and a water-content of >=5wt% in the production of a novolac phenolic resin by the reaction of a phenolic compound with an aldehyde in the presence of an acidic catalyst. The amount of the ammonium halide is 0.05-3wt% based on the solid component of the resin.
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