A support structure for a non-pneumatic tire and a tire incorporating such support structure. A continuous membrane extends between a radially-inner leg and a radially-outer leg. Joints and reinforcement may be provided on sides of the membrane. An annular band may be connected with the radially-outer leg. A wheel, hub, or other structure may be connected with the radially-inner leg.

A modulus at 300% elongation of a cap tread ranges from 3.0 Mpa to 7.0 Mpa, a modulus at 300% elongation of a undertread ranges from 10.0 Mpa to 20.0 Mpa, and a modulus at 300% elongation of an earthing tread ranges from 10.0 Mpa to 20.0 Mpa. Additionally, an earthing tread is made from a rubber material with a volume resistivity of 1×10{circumflex over ( )}7Ω.Math.cm or less. The undertread includes a thickened portion in a region between the earthing tread and an edge portion of a block. The gauge of the undertread gradually increases from the earthing tread toward the edge portion of the block due to the thickened portion.

The tire includes a tread that has a contact face of a width TW and is provided with a groove of a depth D. The tread has a center region and a pair of shoulder regions. The shoulder regions each have a shoulder rubber layer of a thickness is made of a shoulder rubber composition. A shear storage modulus G′ of the shoulder rubber composition is less than or equal to 1.0 MPa. The tire also has a cap ply whose cable extends generally in circumferential orientation and is positioned radially inbetween the tread and the ply at least in a region corresponding to the shoulder regions of the tread and the ply. A force F.sub.5% of the cap ply is greater than 900 N per 10 mm of a cap ply width under 5% strain in a direction cable of the cap ply is extending.

In a state in which a pneumatic tire is mounted on a specified rim, inflated to 92% of a specified internal pressure, and loaded with a load of 75% of the maximum load capacity, an average thickness of an undertread rubber is smaller in a center region than in a shoulder region, a ratio (CAO/UAO) is 0.15 or more and 0.95 or less, a ratio (UAI/UAO) is less than 1, and a ratio (L/W) is 0.29 or more and 0.51 or less, in a tire meridian cross-sectional view, where CAO, UAO and UAI are cross-sectional areas of the cap tread rubber, the undertread rubber, and the undertread rubber in the center region, respectively, L is a tire width direction dimension from a defined intersection point to a ground contact edge, and W is a tire width direction dimension of each shoulder region.

A process for the manufacture of a tread band for pneumatic tyres, wherein the blocks thereof comprise different rubber portions characterized by a different hysteresis loss. The process comprises a shredding step, wherein from a first and from a second rubber tread compound a plurality of fragments is manufactured with dimensions of between 6 and 30 mesh; a mixing step, wherein the fragments from the first and second compound are mixed together in order to obtain a mixture wherein said fragments are distributed in a random manner and retain their chemical/physical individuality; and an extrusion step, wherein the mixture from the preceding step is extruded for the manufacture of the tread band. The first and second compounds have different dynamic properties in terms of: dynamic modulus at 30° C., tand at 0° C., tand at 30° C. and tand at 60° C. The fragments retain a chemical/physical individuality both within the mixture formed during the mixing step and within the tread band formed during the extrusion step.

A tread of a tire can include a cap layer and a base layer. A loss tangent of the cap layer at 30° C. may be not greater than 0.30, and a loss tangent of the base layer at 30° C. may be less than the loss tangent of the cap layer at 30° C. The base layer can be inward of a reference end of the tread in an axial direction A fixing layer can be between the cap layer and a carcass in a radial direction. A first end of the fixing layer can be outward of an end of the base layer in the axial direction, or a position of the first end of the fixing layer can coincide with a position of the end of the base layer in the axial direction. Adhesiveness of the fixing layer can be higher than adhesiveness of the cap layer.

Recycled elements and/or renewable resources, such as recycled carbon black or recycled carbon black and recycled particulate rubber, are incorporated into a rubber composition. The rubber composition can be used to manufacture tires or various tire components including tire subtreads.

A radial tire (10), with the sidewalls thereof (20), and the tread thereof (30) arranged for minimizing the temperature of the tire while guaranteeing its electrical conductivity. The tread (30) comprises two wings (311, 312) and a central portion (32). These components rest on a base layer (33) radially on the inside of the tread (30). The base layer (33) contains a lateral portion (331, 332) partly in contact with a tread wing (311, 312). This structure of the crown of the tire, in contact with the carcass reinforcement makes it possible to constitute a preferential conductive pathway of the electric charges between the rim and the ground when the tire is mounted on its rim and flattened on the ground.

To provide a pneumatic tire in which the rolling resistance coefficient is reduced while maintaining steering stability. A total gauge TOGa of a cap tread rubber (11A) and an undertread rubber (11B) and a gauge UTGa of the undertread rubber (11B) satisfy a relationship 0.20 ≤ UTGa/TOGa ≤ 0.40 in a ground contact region defined by a pair of shoulder main grooves (10B) located on both outermost sides in a tire width direction in a tread portion (1). A hardness UTHs of the undertread rubber (11B) is in a range of 62 or more and 67 or less. The hardness UTHs of the undertread rubber (11B) and a hardness CapHs of the cap tread rubber (11A) satisfy a relationship 0.90 ≤ CapHs/UTHs ≤ 1.20. A tan δ (60° C.) of the undertread rubber (11B) is less than 0.06.

A two-wheeled vehicle tyre includes a tread portion being provided with a belt layer and a tread rubber disposed radially outwardly of the belt layer. The belt layer includes steel cords oriented along a tyre circumferential direction. The tread rubber includes a cap rubber forming a tread surface and a base rubber disposed radially inwardly of the cap rubber, wherein 300% modulus (M300c) of the cap rubber is greater than 300% modulus (M300b) of the base rubber, and loss tangent (tan δc) of the cap rubber is smaller than loss tangent (tan δb) of the base rubber.