A pneumatic tire comprising a carcass 11, at least one inclined belt layer 13 having a cord extending inclined at an angle of 30° or more relative to the tire circumferential direction, and a tread 15 arranged outward in the tire radial direction of the inclined belt layer 13, wherein a circumferential cord layer 14 arranged inward in the tire radial direction of the tread 15 has a high-rigidity region and a low-rigidity region and the high-rigidity region has a lower negative ratio in a ground contact width of the tread 15 than the low-rigidity region.

In a pneumatic tire, a belt cover layer is provided on an outer circumferential side of a belt layer in a tread portion and includes organic fiber cords helically wound along a tire circumferential direction. As the organic fiber cord, a polyethylene terephthalate fiber cord is used which has a single yarn size fineness of 700 dtex or less and in which the number of twists is 30 twists or more/100 mm. A layer thickness of the belt cover layer is 1.6 times or more as large as a cord diameter of the organic fiber cord.

A tire having uniform inflation growth is provided. The tire includes a body ply that is displaced from the conventional equilibrium curve along the bead, sidewall, and shoulder portions of the tire in a manner that provides more uniform inflation growth from bead portion to bead portion. Such construction reduces load sensitivity, reduces or eliminates the tire break-in period, and/or decreases the propensity for cracking—particularly along a groove bottom of the tread in the shoulder.

Provided is a pneumatic tire that includes a belt reinforcing layer formed of an organic fiber cord. A belt layer disposed on an outer circumferential side of a carcass layer in a tread portion is formed of monofilament wires having a wire diameter of 0.30 mm or more and 0.45 mm or less. The belt reinforcing layer is disposed on an outer circumferential side of the belt layer, is formed of an organic fiber cord that is made of a polyethylene terephthalate fiber and has an intermediate elongation under 2.0 cN/dtex load of from 2.0% to 4.0%.

An aircraft tire having improved wear properties is provided. The tire includes a belt reinforcement structure (128) that provides a flatter crown and reduces localized tensions. The belt reinforcement structure includes at least two hybrid belt plies (130,132) having free ends that are positioned radially inward of at least one non-hybrid belt ply (134,136). The hybrid belt plies allow for reductions in the overall mass of the tire and improved thermal properties while still meeting requirements for burst pressure and size for aircraft tires.

To provide a tire that is not only improved in durability, steering stability, and low rolling resistance in high-speed driving but also excellent in tire productivity. A tire including a pair of bead cores (11), a carcass including at least one carcass ply (12) extending between the pair of bead cores (11), a belt (13) including at least one belt layer placed outward in a tire radial direction of the carcass, and at least one belt reinforcement layer (14) placed outward in a tire radial direction of the belt (13), in which a reinforcement cord of at least one of the carcass ply (12) and the belt reinforcement layer (14) includes a cord using a polyamide multifilament including a polycondensate of a dicarboxylic acid including an aromatic dicarboxylic acid with a diamine.

A passenger vehicle tire having rolling resistance without negatively affecting the grip and behaviour. The tread (2) has a radial height H.sub.S between 5 mm and 8 mm, a volumetric void ratio T.sub.EV between 22% and 30%, a total volume V.sub.CP of the main voids (241) at least equal to 80% of the total volume V.sub.C of the voids (24), and comprises an elastomeric compound having a glass transition temperature T.sub.g between 22° C. and 5° C., a Shore A hardness between 45 and 65, and a dynamic loss tgδ at 23° C. at least equal to 0.13 and at most equal to 0.39. The metal reinforcers of the working layers (41, 42) are steel monofilaments having a cross section S with a smallest dimension Dmin between 0.20 mm and 0.50 mm. The monofilaments distributed at a density d.sub.T between 100 threads/dm 200 threads/dm, each working layer (41, 42) having a mean radial thickness E.sub.T between D+0.1 mm and D+0.6 mm.

A composite cord is composed of two first strands formed of aramid fibers and one second strand formed of nylon fibers. In a cross section perpendicular to a length direction, a ratio L2/L0 of a length L2 of an exposed surface of the second strand along the outer cord periphery to a length L0 of an exposed surface of the composite cord along the outer cord periphery is in a range of 0.30 or more and 0.40 or less.

In a pneumatic tire according to an embodiment, a belt layer is configured such that the angle of a belt cord relative to the tire circumferential direction is more than 30° and 40° or less. An organic fiber cord of a belt-reinforcing layer, which is placed on the radially outer side of the belt layer, is configured such that when the number of twists per 10 cm length is T (twists/10 cm), the fineness is D (dtex), and the fiber density is ρ (g/cm.sup.3), the twist coefficient K defined as T×(D/ρ).sup.1/2 is 900 to 2,600, and the product of the load at 5% elongation LASE 5% (N) of the organic fiber cord and the end count E (cords/25 mm) of the organic fiber cord is 1,000 N or more.

A pneumatic tire is provided where a profile line in a tire meridian cross section of a center land portion defined by circumferential grooves and located on a tire equator is curved projecting outward in a tire radial direction. A carcass layer and a reinforcing layer include a recess portion curved projecting inward in the tire radial direction in a bottom region of the center land portion.