Insulative moisture vapor permeable membrane and method

Abstract

An insulative moisture vapor transmission membrane with reflective barrier is provided. A method of manufacturing the membrane includes providing metallic powder and incorporating it into a liquefied polyurethane. The membrane may be incorporated into wearable garments either directly, or in a laminate form.

1 . A insulative membrane comprising:
 a mixture of polyurethane and metallic powder wherein the metallic powder is configured to act as a radiant barrier while maintaining the moisture vapor transmission and wind resistant and water resistant capabilities provided by the polyurethane.   
     
     
         2 . The insulative membrane of  claim 1 , wherein the metallic powder comprises aluminum nano-particles. 
     
     
         3 . The insulative membrane of  claim 1 , further configured to be integrated into wearable articles. 
     
     
         4 . Insulative clothing comprising:
 a wearable garment   means for reflecting heat so that the garment maintains moisture vapor transmission.   
     
     
         5 . The insulative clothing of  claim 6 , wherein the means for reflecting heat comprises a metallic reflective powder incorporated into the polyurethane laminate. 
     
     
         6 . An insulative fabric comprising:
 a base fabric;   a microporous film made from a mixture of polyurethane and metallic powder   wherein the metallic powder provides radiant reflection and the polyurethane provides a waterproof barrier while maintaining moisture vapor transmission.   
     
     
         7 . The insulative fabric of  claim 7 , wherein the metallic powder comprises aluminum powder. 
     
     
         8 . A method of making a waterproof, water vapor permeable, reflective membrane comprising:
 liquefying polyurethane grain;   mixing aluminum powder into the liquefied polyurethane grain; and   building up the membrane.   
     
     
         9 . The method of  claim 8 , wherein building up the membrane comprises building it directly on a fabric. 
     
     
         10 . The method of  claim 8 , wherein building up the membrane comprises building it on a substrate to form a sheet.