Process for making sound insulation components

Abstract

A process for making composite contoured sound insulating panels of a type suitable for use adjacent to structural panels of automobile vehicle bodies, which in accordance with one embodiment of the present invention, comprises forming a fibrous pad incorporating controlled amounts of a heat curable thermosetting binder and a heat softenable thermoplastic binder distributed in a controlled manner therethrough. The pad is subjected to a preliminary curing step to bond the fibers together into an integral mass, whereafter a dense liquid vinyl plastisol coating is applied to at least one face surface of the pad, which thereafter is heated to effect a fusion of the coating into a heat softened integral layer, effecting a simultaneous heat softening of the thermoplastic binder, whereafter the heated pad is placed between appropriately contoured mold surfaces and is compressed to impart a preselected contour thereto and localized embossments therein and a desired surface finish to the plastisol layer, while simultaneously cooling the pad to effect a rigidification of the thermoplastic binder and the layer so as to retain the composite pad in the preselected contoured and embossed configuration. In accordance with an alternative embodiment of the disclosed process, the pad is subjected to a preliminary molding step followed by the coating step and is subjected to a final molding step after the plastisol coating has been fused at an elevated temperature.