Patent ID: 7968180

Claim:
An extruded propylene-based resin composite foam formed by extrusion-foaming a molding material comprising a propylene-based resin, comprising: a first extruded foam having a closed cell content of 40 percent or more and an expansion ratio of 10 or more; and a second extruded foam having a closed cell content of less than 40 percent and an expansion ratio of 10 or more, wherein a propylene-based multistage polymer comprising the following first constituent (A) and second constituent (B) is used as the propylene-based resin to form at least one of the first extruded foam and the second extruded foam: (A) the first constituent containing a propylene homopolymer component or a copolymer component of propylene and α-olefin having carbon number of 2 to 8, each having an intrinsic viscosity [η] of more than 10 dL/g, which is measured in a tetralin solvent at 135° C., the first constituent occupying 5 to 20 mass % of the propylene-based multistage polymer; and (B) the second constituent containing a propylene homopolymer component or a copolymer component of propylene and α-olefin having carbon number of 2 to 8, each having an intrinsic viscosity [η] of 0.5 to 3.0 dL/g, which is measured in a tetralin solvent at 135° C., the second constituent occupying 80 to 95 mass% of the propylene-based multistage polymer.