Rubber composition for tire treads

摘要

A tire tread rubber composition including a diene rubber and at least one of silica and carbon black, the composition being characterized in that the amount of extract (E) defined below satisfies the equation (1) and that a hard filler 0.01 to 5 mm in mean particle size and at least 100kg/mm2 in Knoop hardness is used in an amount of 3 to 80 parts by weight per 100 parts by weight of the component rubber of the composition subjected to extraction with acetone/chloroform after the vulcanization of the composition, wherein said equation is E<0.4 (A-38) (1) wherein E and A are as defined in the specification.