| 摘要 |
PURPOSE:To improve an all weather property on a dry and low mu road, by using specific cured rubber composed of specific diolefine rubber compounded with a low temperature softening agent as tread rubber and forming main grooves in a circumferential direction and horizontally crossing grooves in a tread. CONSTITUTION:Tread rubber for a tire is made of cured rubber composed of a rubber component of 100pts.wt. including 10-90pts.wt. of diolefine rubber having a glass transfer temperature of -65 deg. or less and 90-10pts.wt. of diolefine rubber having a glass transfer temperature of -55 deg. or less compounded with 2-30pts.wt. of a low temperature ester softening agent, these components being mixed and cured and having an elastic ratio of 50kg/cm<2> or less when they are fully extended at -20 deg. and a loss coefficient tandelta of 0.3 or more at 30 deg.. A tread is formed with a plurality of main grooves 1, 2 extending in a circumferential direction of the tire and horizontally crossing grooves 8, 9 for providing many block patterns. In addition, sipes of 0.40-0.50cm/cm<2> and 0.45-0.55cm/cm<2> are provided with a shoulder portion and other blocks, respectively. |
