Patent ID: 8256572

Claim:
A sound insulating part for a vehicle, comprising: a mass layer including: a porous fibrous layer formed of a material having a dynamic Young's modulus, wherein the dynamic Young's modulus for the material of the porous fibrous layer has a value of at least about 96·AW·t(Pa), with AW being an area weight (g/m 2 ), and t being a thickness (mm) of the porous fibrous layer; and a barrier layer that is substantially air impervious and that has a thickness of less than about 80(μm); and a decoupling layer adjacent to the mass layer, the decoupling layer comprised of a solid-phase material, wherein the barrier layer is disposed between the porous fibrous layer and the decoupling layer, and wherein the barrier layer, the porous fibrous layer, and the decoupling layer are laminated together.