MANUFACTURE OF FLASHLESS POLYURETHANE PRODUCT

摘要

PURPOSE:To manufacture at high productivity a polyurethane product which is free from flashes and looks well, by a method wherein a polyurethane sealing agent constituted of a combination of specific materials is applied to a joining part of a split molds. CONSTITUTION:At the time of molding of a polyurethane product, a sealing agent containing at least one kind of polyester polyol as a polyol component and at least one kind of polyisocyanate as a curing agent is applied to a joint of a split mold. Since the sealing agent obtained by combining the polyol component and curing agent is used like this, and it is not only that a polyurethane product free from generation of flashes is obtained but also that when the sealing agent is applied once to the mold, continuous molding becomes possible by lasting its effect, a coating process of the sealing agent is unnecessary in the next cycle after the molding of the polyurethane and repeating use of at least scores of times or that or more is possible.