| 摘要 |
PURPOSE:To obtain the titled tire having excellent low fuel consumption and low rolling resistance, by using a rubber material prepared by blending a blend of natural rubber with a specific styrene-butadiene copolymer rubber with carbon black as an underlayer of a double tread. CONSTITUTION:A pneumatic radial tire obtained by using a rubber material, prepared by blending 100pts.wt. rubber consisting of (A) 20-80pts.wt. natural rubber and/or synthetic polyisoprene rubber with (B) 80-20pts.wt. styrene- butadiene copolymer rubber and/or polybutadiene rubber (containing >=10pts.wt. rubber having at least one atomic group expressed by the formula linked to the molecular chain) with (C) 25-75pts.wt. carbon black of 30-50g/kg I2 adsorption and having <=0.1 loss tangent of a vulcanized rubber at 60 deg.C and >=300% elongation at 100 deg.C as an underlayer of a double tread and placing the above- mentioned underlayer not to expose to the surface until a slip sign of a tire is exposed. |
