RUBBER COMPOSITION FOR TIRE TREADS, AND PNEUMATIC TIRE

摘要

The present invention addresses the problem of providing: a rubber composition for tire treads which, when used to make a tire, exhibits excellent steering stability when travelling at high speed, excellent property stability when travelling for long periods of time, excellent wet-grip properties, and excellent fuel consumption performance; and a pneumatic tire obtained using said rubber composition. This rubber composition for tire treads includes: an inorganic filler including silica; and a diene rubber including a carboxyl-modified polymer. The inorganic filler content is 70-170 parts by mass per 100 parts by mass of the diene rubber. The silica content is 70-160 parts by mass per 100 parts by mass of the diene rubber. The carboxyl-modified polymer is obtained by using a nitrone compound (B) having carboxyl groups to modify a styrene-butadiene rubber (A). The content of the carboxyl-modified polymer in the diene rubber is 10-100 mass%. The content of styrene units in the styrene-butadiene rubber (A) is at least 36 mass%. The modification ratio of the carboxyl-modified polymer is 0.02-4.0 mol%.