Patent ID: 7998885

Claim:
A liquid-penetration-resistant water-vapor-permeable multi-layer composite material consisting of; a porous nanofiber web of polymeric fibers, wherein the polymeric fibers of the nanofiber web have a diameter of less than 1000 nanometers and wherein the nanofiber web has a basis weight of 5 to 40 grams per square meter and a surface roughness (ΔRMS) of 1 to 15 micrometers, wherein, the porous nanofiber web has an upper surface and a lower surface, and a water-vapor-permeable, hydrophilic, monolithic, water transport layer, and wherein, said porous nanofiber web is coated on said upper surface with a 5 to 15 micrometers layer of said water-vapor-permeable, hydrophilic, monolithic, water transport layer.