Sound-dampening polyurethane-based composite

Abstract

A sound- and vibration-dampening (NVH) layered composition may be prepared by spraying or spray-foaming a polyurethane heavy layer, and spray-foaming a flexible polyurethane foam layer, under conditions such that the two layers bond integrally with one another without use of glue or other adhesive. Additional layers, that are the same as, or different from, these two layers may also be included in the composition. The layered composition may be used in, for example, automotive applications. The method is faster and requires less hardware and space than conventional methods that include gluing steps or employ heavy molds to withstand the pressures generated therein by methods such as injecting or pouring; however, it may still attain relatively uniform thicknesses even when spraying is done on a substrate that does not become part of the final construction.

Dependencies are inferred from the claim text.