RUBBER COMPOSITION FOR TREAD

摘要

PROBLEM TO BE SOLVED: To obtain a rubber composition which can give a vulcanizate almost free from voids and pores by compounding a rubber component comprising a specified amount of a halogenated butyl rubber and a diene rubber with a specified amount of silica treated with a silane coupling agent. SOLUTION: This composition is prepared by compounding 100 pts.wt. rubber component comprising 5-75 pts.wt. at least one member selected from a halogenated butyl rubber and a halogenated isobutylene/p-methylstyrene copolymer and 25-95 pts.wt. diene rubber with 40-150 pts.wt. silica treated with a silane coupling agent. That is to say, when silica pretreated with a silane coupling by mixing is used, the alcohol formed when the coupling agent is reacted with the silica is evaporated and does not remain in the rubber composition. It is desirable that the silica treated with the silane coupling agent is a product obtained by heat-treating silica and an S-containing silica coupling agent (e.g. a compound of the formula).