Patent ID: 8084509

Claim:
A pre-expanded particulate polypropylene-based resin comprising a resin X, wherein said resin X consists of: a polypropylene-based resin A having a melting point of 140° C. or lower; and a polypropylene-based resin B having a melting point of 145° C. or higher, and said resin X is modified by melt-extruding together with an organic peroxide so as to have a melt index of 5 g/10 min or more and less than 20 g/10 min, wherein said resin X contains polypropylene-based resin A in a content of 60 wt % or more and 95 wt. % or less and the polypropylene-based resin B in a content of 5 wt % or more and 40 wt % or less, wherein the melt index of said modified resin X is higher in comparison with a melt index of an unmodified resin X to which the organic peroxide is not added, and wherein no resin other than said resin X is present.