Patent ID: 7094828

Claim:
An olefin thermoplastic elastomer composition having superior resistance to oils, comprising the components (A) 70–90 parts by weight of a polypropylene resin having a melt flow rate (determined at 230° C. under a load of 2.16 kg according to ASTM D 1238) of 0.1–3 g/10 minutes, (B) 10–30 parts by weight of a copolymer rubber based on olefin, the contents of the components (A) and (B) summing up to 100 parts by weight, wherein the copolymer rubber based on olefin consists of one or more rubbers selected from the group consisting of copolymer rubbers consisting of ethylene/another α-olefin; copolymer rubbers consisting of ethylene/another α-olefin/non-conjugated diene which diene is selected from the group consisting of dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene and ethylidene norbornene; copolymer rubbers consisting of propylene/another α-olefin; and copolymer rubbers consisting of butene/another α-olefin, and (C) 20–150 parts by weight of a softener, wherein the composition is melt-kneaded in the presence of an organic peroxide to bring it into a cross-linked state such that the gel content thereof amounts to 97% by weight or higher.