| CPC A61L 27/48 (2013.01) [B32B 27/40 (2013.01); A61L 2430/20 (2013.01); B32B 2255/02 (2013.01); B32B 2255/26 (2013.01); B32B 2262/0253 (2013.01); B32B 2270/00 (2013.01); B32B 2307/538 (2013.01); B32B 2307/546 (2013.01); B32B 2307/7265 (2013.01)] | 16 Claims |

|
1. A composite sheet having a thickness of 25-250 μm and comprising:
(a) 10-70 mass %, based on the total mass of the composite sheet, of a knit fabric having thickness of 15-225 μm and comprising strands of 2-50 dtex, the strands comprising biocompatible polymer fibers, the strands comprising biocompatible polymer fibers, wherein the fabric comprises a thickness in a plurality of first locations, and pores in a plurality of second locations; and
(b) 30-90 mass %, based on the total mass of the composite sheet, of a polyurethane coating, wherein the polyurethane coating coats the fabric and fills the pores of the fabric such that the composite sheet is substantially impermeable to water; wherein
the composite sheet has a 1% secant modulus of from 1 to 100 MPa and a hardening transition point of from 5 to 75% in each of two orthogonal directions and the diagonal thereof.
|