Patent ID: 7153906

Claim:
A resin composition for a battery case for secondary battery consisting of: (a) about 100 parts by weight of a polypropylene type resin having a density of propylene polymer portion of about 0.905 g/cm 3 or more arid an MFR at 230° C. with a load of 21.18 N of about 0.1 to 12 g/10 min, composing a matrix phrase, (b) about 0.5 to 10 parts by weight of a hydrogenated block copolymer having a number average molecular weight of about 100,000 or more, in terms of polystyrene, as measured by gel permeation chromatography (GPC), and being obtained by hydrogenating a block copolymer comprising at least two polymer blocks A which mainly comprise vinyl aromatic compound units and at least one polymer block B which mainly comprises conjugated diene compound unit(s), wherein the bonded vinyl aromatic compound units has a content of 26 to 55 wt %, composing a dispersed phase polymer, which forms a boundary phase with the matrix phase (a).