Air-Permeable Composite Fabric

Abstract

An air-permeable composite fabric is provided. The composite fabric has an inner fabric layer, an outer fabric layer, and an intermediate vapor barrier. The vapor barrier is selected from adhesive material and an adhesive/membrane combination designed so the composite fabric has a level of air permeability to allow air flow between the first fabric layer and the second fabric layer and a variable level of water vapor diffusion resistance that decreases as air speed impinging on the composite fabric increases.

1 . An air-permeable composite fabric comprising:
 a first fabric layer;   a second fabric layer; and   an intermediate, air-permeable vapor barrier disposed between and bonded to said first fabric layer and said second fabric layer, wherein:
 said intermediate, air-permeable barrier layer is a continuous film mechanically altered by crushing the composite fabric between a plurality of rollers; 
 said intermediate, air-permeable vapor barrier layer has a level of air permeability to allow air flow between said first fabric layer and said second fabric layer, and 
 said intermediate, air-permeable vapor barrier layer has a variable level of water vapor diffusion resistance that substantially decreases as air speed of moving air impinging on said composite fabric increases. 
   
     
     
         2 . The air-permeable composite fabric of  claim 1 , wherein said membrane is made from a material selected from the group consisting of polyurethane, polyamide, polytetrafluoroethylene, polyester and combinations thereof. 
     
     
         3 . The air-permeable composite fabric of  claim 1 , wherein said intermediate, air-permeable barrier layer is a continuous film mechanically altered by crushing the composite fabric between a plurality of rollers that are heated. 
     
     
         4 . The air-permeable composite fabric of  claim 3 , wherein said plurality of rollers are heated to a temperature of between about 100° F. and 375° F. 
     
     
         5 . The air-permeable composite fabric of  claim 1 , wherein at least one of said first fabric layer and said second fabric layer has a raised surface. 
     
     
         6 . The air-permeable composite fabric of  claim 1 , wherein said intermediate, air-permeable vapor barrier is adhered to said first fabric layer and said second fabric layer with an adhesive. 
     
     
         7 . The air-permeable composite fabric of  claim 6 , wherein said adhesive is selected from the group consisting of polyurethane, acrylics, polyamides, polyesters and combinations thereof.