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A polypropylene resin composition which comprises:(1) 55 to 75% by weight of (A) a polypropylene resin consisting of a mixture of the following polymers (i) and (ii):(i) a propylene-ethylene block copolymer having a propylene homopolymer part which is the first segment and having a propylene-ethylen

A polypropylene resin composition which comprises:(1) 55 to 75% by weight of (A) a polypropylene resin consisting of a mixture of the following polymers (i) and (ii):(i) a propylene-ethylene block copolymer having a propylene homopolymer part which is the first segment and having a propylene-ethylene random copolymer part which is the second segment and(ii) a propylene homopolymer having an intrinsic viscosity [.eta.]P of 0.8 to 1.8 dl/g as measured in tetralin at 135.degree. C.,(2) 21 to 30% by weight of (B) an ethylene-1-octene copolymer rubber having a melt flow rate (JIS-K-6758 at 190.degree. C.) of 2 to 10 g/10 min and having a 1-octene component content of 20 to 25% by weight, and(3) 5 to 20% by weight of (C) talc having an average particle diameter of not more than 3 .mu.m, wherein when the amount of the second segment contained in the propylene-ethylene block copolymer of the polypropylene resin (A) is designated as (A)' and the ethylene-1-octene copolymer rubber content is designated as (B)', the following expression is satisfied:0.10.ltoreq.{(A)'/[(A)'+(B)']}.ltoreq.0.30,and when the above composition is subjected to a tensile test according to ASTM D638, it exhibits, an ultimate elongation of at least 400%, and the melt flow rate (JIS-K-6758 at 230.degree. C.) of the composition is at least 30 g/10 min, and an injection-molded article obtained by injection molding the above polypropylene resin composition.

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1. A polyropylene resin composition which comprises:(1) 55 to 75% by weight of (A) a polypropylene resin consisting of a mixture of the following polymers (i) and (ii): (i) 10 to 40% by weight of a propylene-ethylene block copolymer comprised-of a propylene homopolymer first segment and a propylene-

1. A polyropylene resin composition which comprises:(1) 55 to 75% by weight of (A) a polypropylene resin consisting of a mixture of the following polymers (i) and (ii): (i) 10 to 40% by weight of a propylene-ethylene block copolymer comprised-of a propylene homopolymer first segment and a propylene-ethylene random copolymer second segment, said second segment having an ethylene content of 25 to 55% by weight, and said second segment being present in said block copolymer in an amount of 5 to 30% by weight and (ii) 90 to 60% by weight of a propylene homopolymer having an intrinsic viscosity [.eta.]P of 0.8 to 1.8 dl/g as measured in tetralin at 135.degree. C., wherein the amount of (i)+(ii) is 100% by weight, (2) 21 to 30% by weight of (B) an ethylene-1-octene copolymer rubber having a melt flow rate measured according to JIS-K-6758 under a load of 2.16 kg at 190.degree. C. of 2 to 10 g/10 min and having a 1-octene component of 20 to 25% by weight, and (3) 5 to 20% by weight of (C) talc having an average particle diameter of not more than 3 .mu.m, wherein when the amount of the second segment contained in the propylene-ethylene block copolymer of the polypropylene resin (A) is designated as (A)' and the ethylene-1-octene copolymer rubber content is designated as (B)', the following expression is satisfied: 0.10.ltoreq.{(A)'/[(A)'+(B)']}.ltoreq.0.30, when the composition is subjected to a tensile test according to ASTM D638 at 23.degree. C., it exhibits an ultimate elongation of at least 400%, and the melt flow rate measured according to JIS-K-6758 under a load of 2.16 kg at 230.degree. C. of the composition is at least 30 g/10 min.