To obtain the subject expanded particle capable of providing an excellent expanded molding product even by heating using a low-pressure saturated steam by using a high-melting noncross-linked propylene-based random copolymer as a base resin.
This polypropylene-based resin expanded particle obtained by using a noncross-linked propylene-based random copolymer having ≥140°C melting point as a base resin has ≥80 minute damping time in which air pressure in the particle provided by heat-treating the expanded resin with air is damped from 1.2 kgf/cm2 to 0.8 kgf/cm2 under atmospheric pressure at 23°C and <3.80 CNI calculated by the equation [Pw is an average weight (mg) of one expanded particle; Er is an expansion ratio (times) of bulkiness of the expanded particle; D is a foam diameter (mm) of the expanded particle; A is a density (g/cm3) of the base resin]. The objective expanded particle has preferably 0.2 to ≤1.1 mg Pw and 40-80 times expansion ratio. An expanded molding product having a few voids or no void at all and excellent appearance can be obtained by using the expanded particle.
SAKAGUCHI MASAKAZU
AKIYAMA MITSUHIRO
TOKORO TOSHIO
