METHOD FOR PREPARING NOVOLAK TYPE AROMATIC HYDROCARBON-FORMALDEHYDE RESIN, EPOXY RESIN CURING AGENT AND EPOXY RESIN COMPOSITION

摘要

PURPOSE:To prepare the subject resin useful as a curing agent for epoxy resins and giving cured products having excellent water resistance, by reacting a resol type phenolic resin with a condensed polycyclic aromatic hydrocarbon containing phenolic hydroxyl groups. CONSTITUTION:(A) A resol type phenolic resin (preferably a resin produced from a phenol compound and an aldehyde in the presence of a basic catalyst) is reacted with (B) a condensed polycyclic aromatic hydrocarbon having a phenolic hydroxyl group) (e.g. alpha-naphthol) preferably so that the equivalent of the methylol groups in the component A is the same as the equivalent of hydrogen atoms capable of reacting with the formaldehyde in the component B or so that the equivalent of the hydrogen atoms in the component B is excessive, thus providing the objective resin.