RUBBER COMPOSITION AND PNEUMATIC TIRE USING SAME IN TIRE TREAD

摘要

PROBLEM TO BE SOLVED: To provide a rubber composition comprising thermally expandable microcapsules having a specific moisture content under undried condition. SOLUTION: The rubber composition contains 100 pts.wt. of a diene rubber and 1-20 pts.wt. of thermally expandable thermoplastic resin microcapsules moistened with water and comprising a thermoplastic resin enclosing a substance generating a gas by vaporizing or expanding by heat. The shell material of the thermally expandable microcapsules comprises a thermoplastic resin prepared by the copolymerization of a nitrile monomer (I) as a main component, a monomer (II) having an unsaturated double bond and a carboxy group in the molecule, a monomer (III) having two or more polymerizable double bonds and optionally a co-polymerizable monomer (IV) for adjusting the characteristic feature of thermal expansion. COPYRIGHT: (C)2008,JPO&INPIT