RUBBER COMPOSITION AND PNEUMATIC TIRE

摘要

PROBLEM TO BE SOLVED: To provide a rubber composition which, without degrading abrasion resistance, achieves well-balanced improvement of its low rolling resistance and wet performance contradictorily relating to each other. SOLUTION: The rubber composition contains a rubber component consisting of at least 40 pts.wt. styrene-butadiene rubber (SBR-A) per 100 pts.wt. of the rubber component and at least one kind of a diene rubber other than the above SBR-A and also contains silica. The value of styrene content Z obtained from a bound rubber of the rubber composition is in the range represented by formula (1): ((a×A+b×B)/100)×(0.9-2.9/A)