Patent ID: 7182896

Claim:
A method of producing a composite foamed polypropylene resin molding, comprising: providing a mold having a mold cavity including a plurality of contiguous spaces; filling expanded beads of a base resin including a polypropylene resin in each of said spaces; and heating said expanded beads in each of said spaces to fuse-bond respective expanded beads together to form the composite foamed molding with a plurality of sections, corresponding to the plurality of contiguous spaces, fuse-bonded together, at least two of said sections differing from each other in apparent density; wherein each of said expanded beads shows a high temperature endothermic peak, in a DSC curve thereof, in addition to an intrinsic endothermic peak located at a lower temperature side of said high temperature peak, and wherein those expanded beads which are filled in at least one of said spaces are specific expanded beads which satisfy the following conditions (a) to (c) at the same time: (a) said specific expanded beads are formed of a base resin having a tensile modulus of at least 1,200 MPa, (b) said specific expanded beads have an apparent density D 1 g/L which is not smaller than 10 g/L but not greater than 700 g/L, and (c) the high temperature endothermic peak of said specific expanded beads has a calorific value of E 1 J/g, wherein D 1 and E 1 have the following relationship 20−0.014× D 1≦ E 1≦65−0.072× D 1.