PNEUMATIC TIRE WITH IMPROVED ON-ICE/SNOW TRACTION

PURPOSE:To provide a pneumatic tire of composite tread structure having on-ice/snow traction while maintaining the excellent dry and wet/dry characteristics by providing the outer layer component made of rubber of low elasticity for low temperature use and the inner layer component made of rubber of high elasticity for low temperature use which is thicker than the outer layer component. CONSTITUTION:A tire 10 is generally of pneumatic type, and provided with tread reinforcing belts 11, 12, a body ply 13, an inner side liner 14, a bead 15, a first bead apex 16, a bead toe 18, a second bead apex, a side wall 20, and a shoulder 21, and provided with a composite tread 22 made of at least two distinguishable materials. An outer side layer 23 has low elasticity which is effective at -20 deg.C in improving the on-ice/snow traction, and contains the rubber of low glass-transition temperature (Tg). A core inner side layer 24 has high elasticity at -20 deg.C, and contains the rubber of high glass-transition temperature. Thus, the on-ice/snow traction of the tire is improved by employing the composite tread having the inner and outer side components to the tire carcass before solidification.