| 摘要 |
PROBLEM TO BE SOLVED: To provide a rubber composition for a tread that exhibits excellent low-heat buildup performance and achieves reduction in fuel consumption of a vehicle. SOLUTION: The rubber composition for a tread includes at least 10 pts.mass of silica (A) having an average primary particle size of at least 20 nm and at least 5 pts.mass of silica (B) having an average primary particle size of less than 20 nm, and 100 pts.mass of a rubber component, and a silane coupling agent having 1-70 mol%, based on the total of a bonding unit A represented by formula (1) and a bonding unit B represented by formula (2), of the bonding unit B. In the formulae, x and y are each an integer of 1 or larger; R<SB>1</SB>is hydrogen, a halogen atom, a 1-30C branched or unbranched alkyl group, or a 2-30C branched or unbranched alkenyl group, and the end of the alkyl group or the alkenyl group may be substituted with a hydroxy group or a carboxy group; R<SB>2</SB>is hydrogen, a 1-30C branched or unbranched alkyl group, or a 2-30C branched or unbranched alkenyl group; and R<SB>1</SB>and R<SB>2</SB>may form together a cyclic structure. COPYRIGHT: (C)2011,JPO&INPIT |
