Acoustical insulator for a vehicle

Abstract

An acoustical and thermal insulator provided which is suitable for use in a vehicle. The insulator includes a nonlaminate acoustical and thermal insulating layer of blend of polymer fibers and natural fibers. The fiber blend provides a lower cost material with similar acoustical, thermal properties. The insulator includes a relatively high density, nonlaminate layer of the fiber blend and/or one or more facing layers constructed from various materials.

1 . An acoustical and thermal insulator, comprising: 
 a single, multidensity nonlaminate acoustical and thermal insulating layer formed of a combination of polymeric and natural fibers, wherein said acoustical and thermal insulating layer includes a first processed surface formed by the application of heat to a first surface of said acoustical and thermal insulating layer, said first processed surface having a higher density than an adjacent portion of said insulating layer.    
     
     
         2 . The insulator of  claim 1 , wherein said acoustical and thermal insulating layer has a weight per unit area of between about 20-130 g/ft 2 .  
     
     
         3 . The insulator of  claim 1 , further comprising a first facing layer over the first processed surface of said acoustical and thermal insulating layer, said first facing layer being constructed from a material selected from a group consisting of polyester, rayon, polyethylene, polypropylene, ethylene vinyl acetate, polyvinyl chloride, fibrous scrim, metallic foil and mixtures thereof.  
     
     
         4 . The insulator of  claim 3 , wherein said acoustical and thermal insulating layer and said first facing layer are approximately the same color.  
     
     
         5 . The insulator of  claim 1 , further comprising, a second processed surface formed by the application of heat to a second surface of said acoustical and thermal insulating layer, said second processed having a higher density than an adjacent portion of said insulating layer.  
     
     
         6 . The insulator of  claim 5 , further comprising a second facing layer over said second processed surface, said second facing layer selected from a group consisting of polyester, rayon, polyethylene, polypropylene, ethylene vinyl acetate, polyvinyl chloride, fibrous scrim, metallic foil and mixtures thereof.  
     
     
         7 . An insulator panel, comprising: 
 a single, nonlaminate acoustical and thermal insulating layer including a mixture of polymer and natural fibers, wherein said acoustical and thermal insulating layer includes a first densified surface being formed by the application of heat to a first surface of said acoustical and thermal insulating layer, said first densified surface having a higher density than an adjacent portion of said insulating layer.    
     
     
         8 . The insulator panel of  claim 7 , wherein the polymer fibers are selected from the group consisting essentially of polyester, polypropylene, polyethylene, rayon, nylon and any mixtures thereof.  
     
     
         9 . The insulator panel of  claim 7 , wherein the natural fibers are selected from the group consisting essentially of cotton, hemp and kenaf and any mixtures thereof.  
     
     
         10 . The insulator of  claim 7 , further comprising a first facing layer over the first densified surface.  
     
     
         11 . The insulator of  claim 10 , wherein said first facing layer is selected from the group consisting of polyester, rayon, polyethylene, polypropylene, ethylene vinyl acetate, polyvinyl chloride, fibrous scrim, metallic foil and mixtures thereof.  
     
     
         12 . The insulator of  claim 7 , further comprising, a second densified surface being formed by the application of heat to a second surface said second densified surface having a higher density than an adjacent portion of said insulating layer.  
     
     
         13 . The insulator of  claim 12 , including a second facing layer over said second densified surface.  
     
     
         14 . The insulator of  claim 7 , wherein said acoustical and thermal insulating layer has a weight per unit area of between about 20-130 g/ft 2 .  
     
     
         15 . A process for forming a multilayer insulator, comprising the steps of: 
 forming an insulator precursor of polymer and natural fibers, said polymer fibers being selected from the group consisting essentially of polyester, polypropylene, polyethylene, rayon, nylon and mixtures thereof and said natural fibers being selected from the group consisting essentially of cotton, hemp, kenaf and mixtures thereof.    applying heat to a first major surface of said insulator precursor;    applying pressure to said insulator precursor whereby said applied heat and said applied pressure mold said insulator precursor to a desired shape while also providing said precursor with a first zone having a first density (A) adjacent said first major surface and a second zone having a second density (B) adjacent said first zone.    
     
     
         16 . The process of  claim 15 , wherein said heat and said pressure are applied by a first molding element and wherein said first molding element is heated to provide a first temperature in said first zone above a softening temperature characteristic of said polymer fiber.  
     
     
         17 . The process of  claim 15 , further comprising the step of: 
 applying heat applying a second major surface of said insulator precursor to provide said precursor with a third zone having a third density (C) adjacent said second major surface and a second zone having a second density (B) adjacent said third zone.    
     
     
         18 . The process of  claim 17 , wherein said heat and said pressure are applied by a first and second molding elements and wherein said first and second molding elements are heated to provide a temperature above a softening temperature characteristic of said polymer fiber.  
     
     
         19 . The process of  claim 15 , wherein said pressure is sufficient to compress said insulator precursor between approximately 10-95% when applying said pressure.  
     
     
         20 . The process of  claim 15 , wherein said pressure is sufficient to compress said insulator precursor between approximately 50-90% when applying said pressure.