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 an excellent 300% modulus and excellent rubber hardness at high temperatures, and excellent dry grip characteristics; and a pneumatic tire using said rubber composition. This rubber composition for tire treads includes carbon black, and a diene rubber including a carboxyl-modified polymer. The carbon black content is 80-150 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%.