| 摘要 |
A polypropylene-based resin composition comprising:(1) 95 to 50% by weight of a polypropylene-based resin (A) of a mixture of the following (i) and (ii);(i) a crystalline propylene-ethylene block copolymer comprising a propylene homopolymer portion as a first segment and a propylene-ethylene random copolymer as a second segment, said propylene-ethylene block copolymer having a melt flow rate at 230° C. measured according to JIS-K-6758 of not less than 25 g/10 min., and(ii) a crystalline propylene homopolymer having a melt flow rate at 230° C. measured according to JIS-K-6758 of not less than 70 g/10 min.;(2) 5 to 20% by weight of at least one rubber (B) selected from the following rubbers (a) and (b);(a) an ethylene-alpha-olefin copolymer rubber,(b) an alkenyl aromatic compound-containing rubber; and(3) 0 to 30% by weight of talc (C) having an average particle diameter of not more than 3 mum, the total amount of (A), (B) and (C) being 100% by weight, wherein said polypropylene-based resin composition satisfies the following expression:in which (A)' represents an amount of the second segment in the polypropylene-based resin composition, (a') represents an amount of the ethylene-alpha-olefin copolymer rubber in the polypropylene-based resin composition, and (b') represents an amount of the alkenyl aromatic compound-containing rubber in the polypropylene-based resin composition, andwherein the melt flow rate at 230° C. measured according to JIS-K-6758 of said polypropylene-based resin composition is not less than 35 g/ 10 min. and the flexural modulus at 23° C. is not less than 8000 kg/cm2.
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