PURPOSE: To obtain the titled product having improved appearance, mechanical strength and heat resistance by the one-shot method at a low cost efficiently, by reacting a mixture of two specific polyols with a polyisocyanate and a specified blowing agent.
CONSTITUTION: (A) 100pts.wt. mixture consisting of (a) 30W70pts.wt. polyol derived from an aromatic amine expressed by formula I [R1, R2, R3, R4, R5 and R6 are groups expressed by formula II (R' is H or CH3; m is 1W10; n is 0W3)] and (b) 70W30pts.wt. polyol derived from an aliphatic amine and ammonia is mixed with (B) 5W45pts.wt. halogenated hydrocarbon, e.g. methylene chloride, having a low boiling point (20W100°C) as a blowing agent. The resultant mixture is then mixed with (C) a liquid consisting of a polyisocyanate, preferably hexamethylene diisocyanate, essentially, preferably in a high pressure impact mixer, in a short time injected into a mold and foamed to give the aimed product.
TSUZUKI SUSUMU
GOTOU MASAO
YOKONO ATARU
NAKA REIJI
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