Bead Aye rubber composition and a pneumatic tire for Apex

摘要

PROBLEM TO BE SOLVED: To provide a rubber composition for a bead apex, for improving high fuel efficiency and rubber strength in a good balance, and to provide a pneumatic tire using the composition.SOLUTION: The rubber composition for a bead apex contains 0.1 to 100 parts by mass of silica and 0.1 to 60 parts by mass of a cyclized rubber with respect to 100 parts by mass of a rubber component. In the rubber composition for a bead apex, the cyclization rate of the cyclized rubber is 0.1 to 40%. The cyclized rubber comprises at least one rubber selected from the group consisting of a cyclized natural rubber, a cyclized isoprene rubber and a cyclized butadiene rubber.