Microporous breathable building and construction materials comprising coated woven and/or nonwoven fabrics, and method

摘要

Breathable materials comprise a fabric layer and a polymer film layer thereon, the polymer film layer comprising a polymer composition and a filler, wherein the breathable material has undergone a physical manipulation to render the polymer film layer microporous such that the WVTR of the breathable material is greater than about 50 g/m 24 hr, and wherein the breathable material has a first length dimension and a first width dimension before said physical manipulation and a second length dimension and a second width dimension after said physical manipulation, wherein the second length dimension is no more than about 2% greater than the first length dimension and the second width dimension is no more than about 2% greater than the first width dimension. Methods of making a breathable material comprise forming a polymer film layer comprising a polymer composition and a filler; bonding the polymer film layer to a fabric layer to form a laminate; and applying a physical manipulation to the laminate to render the polymer film layer microporous such that the WVTR of the resulting breathable material is greater than about 50 g/m2 24 hr; wherein the breathable material has a first length dimension and a first width dimension before said physical manipulation and a second length dimension and a second width dimension after said physical manipulation, wherein the second length dimension is no more than about 2% greater than the first length dimension and the second width dimension is no more than about 2% greater than the first width dimension.