A tire comprises a tread portion provided with a band composed of at least one band cord wound spirally and circumferentially of the tire and embedded in the tread portion. When a band cord piece is taken out from the above-said at least one band cord embedded in the tread portion and measured for the length, a length Lb is equal to or smaller than a length La at least in a part of the tread portion, where the length Lb is measured at a first point of time after the band cord piece has been taken out, and the length La is measured at a second point of time after the first point of time.

The present invention provides a tire that uses an elastomer-metal cord composite, which composite is obtained by coating metal cords with an elastomer, each metal cord being composed of a bundle of metal filaments arranged without being twisted, and which composite is capable of highly improving the performance of the tire. The above-described tire is a tire (100) including a belt (105) which includes at least two belt layers (105a) and (105b). In this tire, the belt layers (105a) and (105b) are each obtained by coating metal cords (2) with an elastomer (3), each metal cord (2) being composed of a bundle of a plurality of metal filaments (1) arranged in a row without being twisted; the metal filaments (1) are shaped, and at least one pair of adjacent metal filaments (1) in the metal filaments (1) have different phases from each other; each of the belt layers (105a) and (105b) has a thickness of more than 0.30 mm and less than 1.00 mm; and the distance in the tire radial direction between the metal cords (2) in the two adjacent belt layers (105a) and (105b) is 0.10 mm or more and 1.20 mm or less, at the center of the tire.

The pneumatic tire includes a carcass layer, a belt layer disposed on an outer side of the carcass layer in a radial direction, and a tread rubber disposed on an outer side of the belt layer in the radial direction. Additionally, the carcass layer has a cord angle of 80° or more and 100° or less. Additionally, the belt layer is formed by layering a first reinforcing belt, a second reinforcing belt that is narrower than the first reinforcing belt, and an auxiliary belt that is spaced apart from a tire equatorial plane and disposed between the carcass layer and the first reinforcing belt. Additionally, the first reinforcing belt has a cord angle of 11° or more and 30° or less, the second reinforcing belt has a cord angle of 1° or more and 11° or less, and the auxiliary belt has a cord angle of 55° or more and 70° or less.

The invention is directed to a vehicle pneumatic tire wherein strengthening plies are provided with steel cords running parallel to one another. The belt plies can be used, as isolated electrically conductive plates, for supplying electricity to electrical consumers such as sensors and actuators installed in the tire. Adjacent belt plies can be connected by puncture sensors to be able to identify damage to the belt caused by metallic parts penetrating from the outside, such as nails, on the basis of a change in the electrical resistance.

A plurality of belt layers 7 are superimposed in a radial direction. The belt layers 7 include a plurality of steel cords 10 arranged in parallel in a row and rubber 11. The steel cords 10 have a 1×4 structure in which four filaments 20 are twisted, and when a center-to-center distance between the steel cords 10 in at least two of the belt layers 7 adjacent in the radial direction is T, and an average diameter of virtual circumscribed circles of the steel cords 10 having the 1×4 structure is D, 1.25≤T/D≤2.25.

A tyre includes a tread portion being provided with a pair of shoulder circumferential grooves on an outer surface thereof and a tread reinforcing layer disposed in the tread portion. The tread reinforcing layer includes a circumferential belt layer having a plurality of first reinforcing cords oriented along a tyre circumferential direction. The circumferential belt layer includes a pair of axially spaced first circumferential belt plies extending in radially inner regions of the pair of shoulder circumferential grooves. The pair of first circumferential belt plies is arranged apart from one another at a distance L equal to or more than 20 mm in a tyre axial direction.

A tire with a radial carcass reinforcement, made up of at least one layer of metal reinforcing elements inserted between two skim layers of elastomer compound containing a reinforcing filler made up of at least carbon black. The tensile elastic modulus at 10% elongation of at least the skim layer closest to the internal cavity of at least the carcass reinforcement layer closest to the internal cavity is less than 8.5 MPa and at least the said skim layer closest to the internal cavity of at least the carcass reinforcement layer closest to the internal cavity has a macrodispersion value Z greater than 85.

In a pneumatic tire provided with a carcass layer and a belt layer, the carcass layer is formed of an organic fiber cord having an elongation at break of 20% to 30%, an elongation in a sidewall portion under a load of 2.0 cN/dtex of 5.5% to 8.0%, and a product A = D × Ec of a fineness based on corrected mass D (unit: dtex/piece) and a count Ec (unit: piece/50 mm) of 1.8 × 10.sup.5 dtex/50 mm to 3.0 × 10.sup.5 dtex/50 mm, and the belt layer is formed of a steel cord having a stress at break of 3300 MPa or more and a product B = S x Eb of a cross-sectional area S (unit: mm.sup.2/piece), and a count Eb (unit: piece/50 mm) is from 6.0 mm.sup.2/50 mm to 7.5 mm.sup.2/50 mm.

Provided is a pneumatic tire with which any change in steering stability between low-speed running and high-speed running is sufficiently minimized, and durability is also sufficiently improved. This pneumatic tire has a belt layer radially inward of the tread portion, wherein the ratio (tan δ/E*) of the loss tangent (tan δ) to the complex elastic modulus E*(MPa) of the rubber composition constituting the belt layer, as measured under the conditions of 70° C., frequency 10 Hz, initial distortion 5%, and dynamic distortion rate 1%, is 0.002 to 0.017 (inclusive), and the (formula 1) and (formula 2) are satisfied, where Wt (mm) is the cross-sectional width of the tire, Dt (mm) is the outside diameter, and the virtual volume V (mm.sup.3) is the volume of the space occupied by the tire, when the tire is installed on a standardized rim and the internal pressure is 250 kPa.

1700≤(Dt.sup.2×π/4)/Wt≤2827.4  (formula 1)

[(V+1.5×10.sup.7)/Wt]≤2.88×10.sup.5  (formula 2)

A heavy-duty tire comprises a tread reinforcing belt comprising first to fourth belt plies each composed of belt cords inclined with respect to the tire equatorial plane. The first radial distance L1 between the belt cords of the third belt ply and the belt cords of the fourth belt ply is not more than the second radial distance L2 between the belt cords of the second belt ply and the belt cords of the third belt ply. The cord count E4 of the fourth belt ply is smaller than the cord count E3 of the third belt ply.