Patent ID: 8420743

Claim:
A propylene-based copolymer composed of 60 to 90% by weight of Component (A) that is a polymer component whose major structural unit is a structural unit derived from propylene and 10 to 40% by weight of Component (B) that is a propylene-ethylene copolymer component whose content of a structural unit derived from ethylene is 50 to 80% by weight, wherein the sum total of Component (A) and Component (B) is 100% by weight, wherein the ratio of the intrinsic viscosity of Component (B) ([η]B) to the intrinsic viscosity of Component (A) ([η]A) ([η]B/[η]A) satisfies a formula: 1.3<[η]B/[η]A≦2.0, and the melt flow rate, measured at a temperature of 230° C. and a load of 21.18 N, of the copolymer is not less than 5 g/10 minutes and not more than 30 g/10 minutes.