| 摘要 |
PURPOSE:To provide the title binder which allows curing time to be greatly shortened, scarcely causes lowering of its softening point and is suitable for use in bonding molds, felt, grinding stones, etc. to substrates, by blending a novolak phenolic resin with a specific org. acid and an amino compd. CONSTITUTION:A phenolic resin binder is obtd. by blending a novolak phenolic resin (A) obtd. by condensing one mol. of a phenol (e.g., phenol) with 0.50-0.95mol. of formaldehyde (e.g., formalin) in the presence of an acid catalyst (e.g., oxalic acid) with an org. acid (B) selected from among benzoic acid, salicyl ic acid, adipic acid, succinic acid and phthalic acid and an amino compd. (C) selected from among aminophenols, urea, nitroaniline and melamine. The binder allows curing time to be greatly shortened as compared with conventional agents. Further, the binder scarcely causes lowering of its softening point and does not cause blocking.
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