A hybrid cord having a Nylon core yarn (32) and an Aramid wrap yarn (34) wrapped around the Nylon core yarn (32) is disclosed. The hybrid cord (30) has the cord construction:

(A/1 Aramid + B/1 Nylon) [(x)Z+(y)Z]/(z)S or

(A/1 Aramid + B/1 Nylon) [(x)S+(y)S]/(z)Z

wherein A is the weight per length of the Aramid wrap yarn (34) and is in a range of from 900 to 1100 Denier, B is the weight per length of the Nylon cord yarn (32) in a range of from 700 to 900 Denier, x is the number twists per 2.54 cm of the Aramid wrap yarn (34) and is in a range of from 4 to 6, y is the number twists per 2.54 cm of the Nylon core yarn (32) and is in a range of from 4 to 6, and z is the number twists per 2.54 cm of the hybrid cord (30) and is in a range of from 4 to 6. Also, a pneumatic tire comprising such a hybrid cord is disclosed.

A pneumatic tire (1) including: a pair of bead portions (3) each including a bead core and a bead filler; a carcass layer (5) extending toroidally via a sidewall portion (SW); a tread portion (7) arranged outward of the carcass layer in a radial direction of a tire; and sidewall reinforcement layers (9) which are arranged inward of the carcass layer (5) in a tread width direction, are each formed of rubber having a crescent cross-section in the tread width direction, and reinforces the respective sidewall portions (SW), characterized in that an inside width direction groove (17) is arranged in an inside region (IN) of the tread portion (7), and a circumferential direction groove (23) and an outside width direction groove (25) are arranged in an outside region (OUT) of the tread portion (7).

In a pneumatic safety tire comprising reinforcing rubber layers having an approximately crescent sectional shape for supporting a portion of the load which are disposed on the inner circumferential face of the carcass layer at side walls, a fiber cord constituting a belt reinforcing layer has a size of 1,000 to 7,000 dtex as the entire cord, comprises at least 50% by mass of a polyketone fiber and exhibits a maximum stress of thermal contraction of 0.1 to 1.8 cN/dtex. Buckling deformation of the tread portion can be suppressed, and the run flat performance is improved while the ride quality during driving under the normal internal pressure is not adversely affected and changes in the manufacturing process are not required.

A radial pneumatic tire having excellent run-flat durability. The tire is equipped with a belt layer (4), which includes a plurality of metal cord layers, and a tread (5) successively at a periphery of a crown portion (3) of a toroidal radial carcass (2), and is equipped with, at an inner peripheral surface of the side portion (6) of the carcass, a rubber reinforcing layer (7) having a crescent moon shaped cross-section and bearing and supporting load. The tire has an auxiliary layer (8) disposed between the carcass and the belt layer and including organic fiber cords which are oriented so as to intersect the cords of the carcass and the cords of the belt layer with a central equatorial plane between, on the one hand, the cords of the auxiliary layer, and on the other hand, the cords of the carcass and the cords of the belt layer.

A run-flat radial ply pneumatic tire (10) having a carcass (30) reinforced with elastomeric sidewall fillers (42,46,48) and at least three bead cores (26,26') and (37) is disclosed. At least one bead core (37) extends radially inwardly of the tread (12) and one or more reinforcing belts (36). The tire (10) made according to the invention can exhibit equal to or improved ride over conventional tires while also providing a limited run-flat capability. In several preferred embodiments improved wet traction tread configurations are employed.

A pneumatic radial tire comprising a pair of bead portions (7) and sidewall portions (6) and a tread portion (5) connecting the sidewalls, at least one radial carcass ply reinforcing each of said portions between two beads (2) embedded in the bead portions, a belt (3) comprising at least two layers (3-1, 3-2) having cords intersecting each other, a cap (4) arranged between the belt (3) and the tread portion (5) and having organic fiber cords therein extending in the circumferential direction of the tire, and reinforcing rubber layers (8) in a whole region of the sidewall portions (6) for supporting a load of the tire and each having a crescent shaped cross-section along the inner side of the carcass, characterized in that at least one tie-element layer (9) for resisting force generated in width directions of the tire and having cords extending substantially orthogonally with respect to an equatorial plane of the tire is arranged between the belt (3) and the cap (4).