| 摘要 |
Disclosed herein are foamed and expanded beads of a polypropylene resin for molding, which comprise an uncrosslinked propylene random copolymer having a melting point of at least 140 DEG C. as a base resin, wherein the time required to attenuate an air pressure within the foamed beads applied by a pressurizing treatment with air from 1.2 kgf/cm2(G) to 0.8 kgf/cm2(G) under atmospheric pressure at 23 DEG C. is at least 80 minutes, and the CNI value of the foamed beads, which is defined by the following equation (1):CNI=log10[PwxEr DIVIDED (2.24xD3xB)](1)wherein Pw is an average weight (mg) per foamed bead, Er is a bulk expansion ratio (time) of the foamed beads, D is a cell diameter (mm) of the foamed beads, and B is a density of the base resin, is smaller than 3.80.
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