Patent ID: 7264858

Claim:
A multilayered tube consisting essentially of: a first layer of soft aliphatic polyether polyurethane having an inner and outer surface, wherein said soft aliphatic polyether polyurethane has a Shore hardness from about 40 A to about 95 A as measured according to ASTM D2240; and at least one second layer of hard aliphatic polyurethane selected from the group consisting of polyether polyurethane and polycarbonate polyurethane on at least one of said inner and outer surface of said first layer, wherein said hard aliphatic polyurethane has a Shore hardness from about 95 A to about 85 D as measured according to ASTM D2240, with the proviso that if said hard aliphatic polyurethane is a polycarbonate polyurethane, said Shore hardness of said hard aliphatic polyurethane is from about 70 A to about 80 D; and wherein both of said soft aliphatic polyurethane and said hard aliphatic polyurethane are biocompatible and biostable.