Rubber composition for tire tread having high performance on ice and pneumatic tire using the same

Abstract

A rubber composition for a tire tread, or a pneumatic tire using the same in a tire tread portion, wherein the tread portion contains a diene rubber; and carbon black and/or silica; and a gas-encapsulated thermoplastic resin and, further, a short fiber, a hard particle and/or a liquid polymer, and wherein the gas-encapsulated thermoplastic resin particle is obtained by expanding, upon heating. at a temperature of an expansion starting temperature thereof or more, prior to vulcanization of a rubber, a thermally expansible thermoplastic resin particle, which comprises a thermoplastic resin having an expansion starting temperature of from 70° C. to less than 120° C. and having a heat resistance to withstand vulcanization of rubber, followed by vulcanization to uniformly disperse the gas-encapsulated thermoplastic resin in the rubber, or a short fiber, a hard particle and/or a liquid polymer is further compounded to give a high frictional force on ice.

Dependencies are inferred from the claim text.