A pneumatic tire comprises a carcass layer, a belt layer disposed on the outer side in the tire radial direction of the carcass layer, and tread rubber disposed on the outer side in the tire radial direction of the belt layer. The belt layer is formed by laminating a pair of cross belts having belt angles with an absolute value from 10 to 45 both inclusive and mutually opposite signs, and a circumferential reinforcing layer having a belt angle within a range of 5 relative to the tire circumferential direction. The distance (Gcc) from the tread profile to the tire inner circumferential surface along the tire equatorial plane and the distance (Gsh) from the tread edge to the tire inner circumferential surface have a relationship satisfying 1.10Gsh/Gcc. The groove depth (Dsh) and under-groove gauge (UDsh) of the outermost circumferential main groove have a relationship satisfying 0.20UDsh/Dsh.

The invention relates to a reinforcement layer for elastomeric products, in particular for the belt bandage (8), having cords as reinforcement, where the cords have at least two yarns, where a first yarn of the yarns is made of polyamide and where the ends of all yarns of a cord are twisted together. The problem addressed by the invention is that of providing a reinforcement layer for elastomeric products which exhibits a relatively high tensile force value for an elongation of 4% or more and which exhibits relatively low shrinkage based on linear density of the reinforcement. This is achieved in that the cords are hybrid cords having precisely three yarns, in that the hybrid cord has the first yarn and a second yarn made of HMLS-PET, in that the hybrid cord has a first yarn or a second yarn as third yarn, and in that the linear density of each hybrid cord is at least 5000 dtex.

A plurality of belt layers are laminated in a radial direction. The belt layer includes a plurality of steel cords arranged in parallel and aligned in a row, and rubber. The steel cords have a 14 structure in which 4 filaments are stranded. [Tensile rigidity][number of ends] is 10,000 N/% or greater and 20,000 N/% or less, and an interface rigidity is 2.5 MPa or higher and 5.0 MPa or lower.

A pneumatic tire comprises a carcass layer, a belt layer disposed on the outer side in the tire radial direction of the carcass layer, and tread rubber disposed on the outer side in the tire radial direction of the belt layer. The belt layer is formed by laminating a pair of cross belts having belt angles with an absolute value from 10 to 45 both inclusive and mutually opposite signs, and a circumferential reinforcing layer having a belt angle within a range of 5 relative to the tire circumferential direction. The distance (Gcc) from the tread profile to the tire inner circumferential surface along the tire equatorial plane and the distance (Gsh) from the tread edge to the tire inner circumferential surface have a relationship satisfying 1.10Gsh/Gcc. The groove depth (Dsh) and under-groove gauge (UDsh) of the outermost circumferential main groove have a relationship satisfying 0.20UDsh/Dsh.

A radial tire comprises a multilayer composite laminate (10) comprising at least three superposed layers of reinforcers (110, 120, 130), the reinforcers being unidirectional within each layer and embedded in a thickness of rubber (C1, C2, C3, respectively), with a first layer of rubber (C1) comprising at least one row of heat-shrinkable circumferential textile reinforcers (110), for example made of nylon or polyester. The first layer radially (in the direction Z) surmounts two other layers (C2, C3) comprising metal reinforcers (120, 130) which are crossed from one layer to the next, in the form of steel monofilaments of a diameter between 0.20 mm and 0.50 mm. The reinforcers (110) made of heat-shrinkable textile material are tapes of thickness denoted T between 0.1 mm and 1 mm, and of thickness denoted W between 2 and 50 mm.

The present technology provides a pneumatic tire having a strip-shaped sound-absorbing member bonded on the inner surface of the tire includes a plurality of belt layers, two or more belt cover layers, one or more belt edge cover layers, and a thread rubber layer. The thickness of the tread rubber layer is substantially uniform in the region X where the sound-absorbing member is located so that the difference between the thickness t1 at an end of the sound-absorbing member and the thickness t0 at the position of the tire equator is equal to or less than 0.5 mm. The thickness of the tread rubber layer is smaller in the region Y where the belt edge cover layer is located than in the region X so that the difference between the minimum value t2 of the thickness in the region Y and the thickness t0 ranges from 1.0 to 4.0 mm.

A pneumatic tire comprising a carcass 12, at least one inclined belt layer 13, at least one first circumferential cord layer 14 arranged inward in the tire radial direction of the inclined belt layer 13, a tread 16 arranged outward in the tire radial direction of the inclined belt layer 13, and a second circumferential cord layer 15 which is arranged outward in the tire radial direction so as to cover a tire width direction end of the inclined belt layer 13, and where X is defined as X=Y=nmd, Y is the Young's modulus (GPa) of the cord, n is the number of cords implanted (cords/50 mm), d is the cord diameter (mm), and m is the number of the first circumferential cord layers 14, X is smaller than X of the first circumferential cord layer 14.

A rubber composition has an improved rolling resistance and is based on at least a diene elastomer comprising mainly at least one isoprene elastomer; a reinforcing filler comprising from 15 to 70 phr of carbon black having a BET specific surface area of less than 70 m.sup.2/g, and/or a COAN of less than 90 ml/100 g, and from 5 to 20 phr of silica; a salt of an alkaline-earth, alkali or lanthanide metal; and a crosslinking system; in which composition the carbon black to silica ratio is greater than 1.

A pneumatic tire that can improve high speed durability while reducing a tire weight is provided. The pneumatic tire comprises a carcass, a belt layer comprising a cord inclined to a tire circumferential direction and arranged on the periphery of a crown of the carcass, and a belt reinforcing layer comprising an organic fiber cord arranged on the periphery of the belt layer along a tire circumferential direction. The organic fiber cord comprises an aromatic polyamide fiber having a fineness of 500 to 3,000 dtex, and has a single twist construction having a twist coefficient of 800 to 2,000.

A radial tire with a lightened belt structure (10) comprises a multilayer composite laminate (10a, 10b, 10c) of specific construction, with a first layer (10a) of rubber (C1) reinforced with preferably weakly heat-shrinkable circumferential textile multifilament fibres (110) twisted individually on themselves with a torsion T greater than 100 turns per meter, for example, made of nylon or of polyester, this first layer radially (in the direction Z) surmounting two other layers (10b, 10c) of rubber (C2, C3, respectively) reinforced with monofilaments (120, 130) of high tensile steel. The first reinforcers have an envelope diameter between 0.30 mm and 0.60 mm and a density, measured in the axial direction Y, between 90 and 150 threads/dm, and the second and third reinforcers each have a diameter between 0.20 mm and 0.50 mm and a density, measured in the axial direction Y, between 100 and 180 threads/dm.