BINDER FOR CASTING

摘要

PURPOSE:To obtain a twin pack binder for castings which cures at a room temp. by mixing a polyisocyanate compd. and a polyol compd. having a tertiary amino group. CONSTITUTION:Diphenylmethane diisocyanate as a polyisocyanate compd. and a polyol compd. having a tertiary amino group in the molecule obtd. by the reaction of a glycidyl ether type epoxy compd., which is a compd. having >=2 diethanol amines or monoethanol amines and oxirane rings and a bisphenol type epoxy resin are added to silica sand under kneading, and the mixture prepd. in such a way is used as a binder. Ethylene glycol or the like is dissolved in a solvent contg. no active hydrogen and the soln. thereof is used in combination with said binder at the concn. ranging 40-80wt% so that the rate of curing is requlated or the binder is made adequate for use in a high temp. range.