Patent ID: 6749923
Filing Date: 2004-06-15
Classification: A61L,C08K,Y10T

Abstract:
A moisture vapour permeable liquid impervious composite substrate comprising:(a) a thermoplastic film made from a moisture vapour permeable, liquid impervious, non water degradable thermoplastic composition, said composition comprising a blend of from 10% to 80% by weight of a polymer, and from 20% to 90% by weight of a plasticizer, wherein said polymer is selected from the group consisting of polyurethanes, poly-ether-amides block copolymers, polyester block copolymers, and poly-ether-ester-amide block copolymers and mixtures thereof; said composition having a viscosity of from 50 poise to 400 poise at any of 1 rad/s at a temperature of 210Â° C. or less and a viscosity of less than 2000 poise at a frequency of 1000 rad/s at a temperature of 210Â° C. or less; said film having a thickness of from 0.5 micrometers to 10 micrometers; and (b) a support layer, said layer being moisture vapour permeable; wherein said composite substrate has a water vapour transfer rate of at least 300 g/m2/24 hrs at 23Â° C.