RUBBER COMPOSITION FOR TIRE TREAD

摘要

PROBLEM TO BE SOLVED: To improve the dispersibility of a filler in a rubber composition for tire sidewalls and to improve flexural fatigue resistance. SOLUTION: This invention relates to a rubber composition for tire sidewalls containing 100 pts.wt. of rubber comprising (A) 30-70 pts.wt. of natural rubber (NR) and/or polyisoprene rubber (IR) and (B) 70-30 pts.wt. of polybutadiene rubber (BR) and/or styrene-butadiene copolymer rubber (SBR) comprising≥10 pts.wt. of polybutadiene rubber having a linearity index of 110-140 and a Newtonian flow index (n) of 2.2-3.0 (provided that the total amount of the components (A) and (B) is 100 pts.wt.), and (C) 30-70 pts.wt. of carbon black having a CTAB of 30-100 m2/g. A pneumatic tire using the rubber composition in sidewalls is also provided. COPYRIGHT: (C)2009,JPO&INPIT