Patent ID: 6969739

Claim:
A diene polymer rubber composition comprising: (A) 100 parts by weight of a raw material rubber comprising (A-1) a diene rubbery polymer which is a conjugated diene rubbery polymer or a conjugated diene-styrene rubbery copolymer, said diene rubbery polymer (1) containing a modified component in an amount exceeding 60 wt. %, as determined by adsorption amount analysis with GPC, using a silica gel as a filler, which modified component is obtained by reacting an active end of the rubbery polymer with a polyfunctional compound having, in its molecule thereof, at least two epoxy groups, (2) having a molecular weight distribution Mw/Mn of 1.05, or greater but less than 2.2, and (3) having a weight-average molecular weight of 100,000 to 2,000,000; and, based on 100 parts by weight of the component (A), (B) 1 to 100 parts by weight of a rubber extension oil; (C) 25 to 100 parts by weight of reinforcing silica; and (D) 1.0 to 20 parts by weight in total of a vulcanizing agent and a vulcanizing accelerator.