A compound of a lateral insert of a run-flat pneumatic tyre comprising a cross-linkable unsaturated chain polymer base that is capable of assuming all of the chemical-physical and mechanical characteristics of an elastomer after cross-linking, a filler, a plasticizing agent and a curing system. The plasticizing agent consists of an aliphatic chain and has a melting temperature of between 50 C. and 100 C.

Tyre suitable for running flat comprising a crown, two sidewalls and two beads, a carcass reinforcement anchored in each bead and a sidewall insert placed in each of the two sidewalls axially internally relative to the carcass reinforcement, such that it is equipped with an electronic device comprising at least one radiofrequency transponder and such that the electronic device is embedded in one of the sidewall inserts.

A run-flat tire comprises a tread portion, sidewall portions, bead portions, and a carcass ply extending between the bead portions. The sidewall portions are each provided therein with a sidewall reinforcing rubber layer having a crescent-shaped cross sectional shape and disposed on the axially inside of the carcass ply. The sidewall portions are each provided in the axially outer surface thereof with a rim protector which projects radially outward most on the radially outside of the radially inner edge of the sidewall reinforcing rubber layer. The bead portions are each provided therein with an axially inside core and an axially outside core between which each radially inner edge portion of the carcass ply is secured. When measured along a normal line drawn normally to the carcass ply from an apex of the rim protector, the thickness of the sidewall reinforcing rubber layer is in a range of from 29% to 35% of the thickness of the tire.

Provided is a tire manufacturing feature in which, even when an electronic component is disposed on a side wall portion in order to secure sufficient communication performance, damage to the tire or to the electronic component is avoided. A pneumatic tire in which an electronic component is disposed in the interior thereof, wherein a protective layer for reinforcing a side wall is provided at a position on the inside of a carcass and on the outside of an inner liner with respect to the tire axial direction, the protective layer has higher rigidity and lower heat generating properties than the side wall, and the electronic component is disposed between the carcass and the protective layer.

The vulcanized rubber of the present invention is a vulcanized rubber, which is formed from a rubber composition containing a rubber component containing a dienic rubber, and a vulcanizing agent, and has a tensile modulus of elasticity at 25% elongation at 100 C. of 1.2 MPa or more, with a ratio of an Sx bond (where x is 3 or more) to all sulfide bonds being 30% or less. The vulcanized rubber, the tire and the run-flat tire of the invention are excellent in durability life.

The present invention provides a tire improved in the run flat durability, having at least one member selected from the group consisting of a side reinforcing rubber layer and a bead filler using a rubber composition having a tensile stress at 50% elongation at 180 C. (M50) of 6.2 MPa or more as a vulcanized rubber physical property.

A run-flat tire includes side reinforcing rubber between a carcass layer and an innerliner layer in sidewall portions, first bead filler rubber arranged inside folded back portions of the carcass layer, and second bead filler rubber arranged outward of the folded back portions of the carcass layer in a lateral direction. In a meridian cross-section, a radial-direction height of the first bead filler rubber is 15% or greater and 40% or less of a cross-sectional height, a radial-direction height of the second bead filler rubber is 35% or greater and 55% or less of the cross-sectional height, a linear distance from a radial-direction outer end to a radial-direction inner end of the second bead filler rubber is 20% or greater and 45% or less of the cross-sectional height, and the second bead filler rubber has a larger cross-sectional area than the first bead filler rubber.

A method of preparing a sidewall support, the method comprising the steps of (i) providing a vulcanizable composition including an elastomer, a filler, a curative, and a eutectic composition; (ii) fabricating the vulcanizable composition into a green sidewall support; and (iii) subjecting the green sidewall support to curing conditions.

The present invention relates to a self-supporting tyre (100) for motor vehicles which comprises sidewall reinforcing inserts (113A, 113B) with different stiffness. In particular, the sidewall reinforcing insert on the side of the tyre most stressed during driving is less rigid than the sidewall reinforcing insert on the less stressed side. The tyre of the invention exhibits a reduced rolling resistance and better comfort in normal driving and an unexpected increase in mileage in run-flat driving.

The run flat tire according to this disclosure comprises a tread portion, sidewall portions, bead portions, a side-reinforcing rubber, and a carcass. An inner liner is provided on the tire inner surface, and an inner layer rubber is disposed between the side-reinforcing rubber and the inner liner. In accordance with JIS K6270, when the dumbbell-shaped No. 8 specimens having 1 mm notch in a direction perpendicular to the direction of repeated tension at the center thereof are subjected to repeated tension at a frequency of 10 Hz under the conditions of 150 C., the number of repetitions until the specimen of the inner layer rubber fails is, in the range of 10% to 30% of the tensile strain applied, at least twice that of the side-reinforcing rubber, and in the reference condition, the ratio t2/t1 is 0.05 to 0.30.