Rubber composition for tire tread, and pneumatic tire using same

摘要

A rubber composition for a tire tread comprising: a diene rubber; a silica having an N2SA of from 194 to 225 m2/g and a CTAB of from 180 to 210 m2/g; and a polysiloxane represented by the average composition formula of formula (1) and contained in an amount of from 1 to 20 mass % with respect to the quantity of silica. (A)a(B)b(C)c(D)d (R1)3SiO(4-2a-b-c-d-e)/2. Also provided is a pneumatic tire having tire treads formed using the rubber composition.

主权项

1. A rubber composition for a tire tread comprising a diene rubber, silica, and a sulfur-containing silane coupling agent;
a nitrogen adsorption specific surface area of the silica being from 194 to 240 m2/g; a CTAB specific surface area of the silica being from 180 to 215 m2/g; a content of the silica being from 60 to 200 parts by mass per 100 parts by mass of the diene rubber; the sulfur-containing silane coupling agent being a polysiloxane represented by the following formula (1); and a content of the sulfur-containing silane coupling agent being from 1 to 20 mass % with respect to the content of the silica;
(A)a(B)b(C)c(D)d(R1)eSiO(4-2a-b-c-d-e)/2  (1) formula (1) being an average composition formula, wherein A is a divalent organic group containing a sulfide group; B is a monovalent hydrocarbon group having from 5 to 10 carbon atoms; C is a hydrolyzable group; D is an organic group containing a mercapto group; R1 is a monovalent hydrocarbon group having from 1 to 4 carbon atoms; and a to e satisfy the relational expressions 0≦a<1, 0≦b<1, 0