Reaction injection molded article with threads and method of molding same

Abstract

A reaction injection molded article formed with threads and a method of molding same, wherein threaded members, such as threaded inserts, helicoils, etc., are positioned in the cavity of a reaction injection mold, and molding material is injected into the cavity to form the threaded members into a unitary structure with a body of the reaction injection molded article. The threaded members are securedly held in place by a surface layer of relatively high density. The molding material is a mixture of an A liquid and a B liquid, the A liquid containing 100 weight parts of polyether polyol obtained by adding alkylene oxide to various kinds of alcohol or amine, 1-5 weight parts of a reaction promoting agent (catalyst) comprising tertiary amines, tin compounds, etc., 3-50 weight parts of water and a foaming agent, such as low boiling point alkylhalide, 1-5 weight parts of a foaming regulating agent, such as alkylene oxide denatured polydimethyl siloxane and 1-20 weight parts, if necessary, of pigment, dyestuff and filler, such as carbon black, diazo compound, silica, glass fiber, etc., and the B liquid containing 100-200 weight parts of MDI, TDI, crude MDI or crude TDI.