PURPOSE: To obtain a phenolic resin foam compsn. having a uniform, fine cell structure and a high closed-cell ratio, by blending a surfactant contg. an ether compd., an acidic hardener and a low-boiling org. blowing agent.
CONSTITUTION: A phenolic resin foam compsn. is obtd. by blending a surfactant, an acidic hardener and a low-boiling org. blowing agent. Said surfactant contains an ether derived from a nonionic surfactant and a methylol group-contg. phenol as at least one surfactant. The surfactant is used in a quantity of 0.1W10pts.wt. per 100pts.wt. resol type phenolic resin precondensate. Said surfactant may be mixed with at least one conventional surfactant. The resol type phenolic resin precondensate can be prepd. by reacting a phenol with an equimolar or excessive amount of an aldehyde in the presence of an alkaline catalyst.
ICHIHARA AKINOBU
UKAI MASAHIRO
DAI ICHI KOGYO SEIYAKU CO LTD