An airless tire includes a tread ring, a hub positioned on radial direction inner side of the tread ring, and a spoke structure connecting the tread ring and hub. The tread ring includes a reinforcing body including a first reinforcing cord layer, a second reinforcing cord layer and a shear layer such that the first layer is extending in tire circumferential direction, the second layer is positioned on tire radial direction inner side of the first layer and extending in the tire circumferential direction, and the shear layer including elastomer is positioned between the first and second layers, and the shear layer includes first and second portions such that the first portion has loss tangent tan and shear modulus Ee in MPa at temperature of 30 C. satisfying tan 0.06 and Ee/tan 1500 and the second portion is formed of material different from material of the first portion.

A pneumatic tire includes bead cores, a carcass ply, an inner liner and the tread, and the crosslinked rubber composition, of the present invention, wherein the tread and the crosslinked rubber composition have a volume of the low density region of 35% or more at elongation by an applied stress of 1.5 MPa, a volume of the void portion of 7.5 or less at elongation by an applied stress of 3.0 MPa and a ratio of 40% by mass or more of a component having a weight-average molecular weight of not less than 1,000,000 in a molecular weight distribution measured by gel permeation chromatography are excellent in abrasion resistance.

The pneumatic tire of the present invention characterized by comprising: bead cores, a carcass ply, an inner liner and a tread having a volume of the low density region of 35% or more, at elongation by an applied stress of 1.5 MPa, a volume of the void portion of 7.5% or less at elongation by an applied stress of 3.0 MPa and a glass transition temperature of 20 C. or lower, and the crosslinked rubber composition of the present invention having a volume of the low density region of 35% or more at elongation by an applied stress of 1.5 MPa, a volume of the void portion of 7.5 or less at elongation by an applied stress of 3.0 MPa and a glass transition temperature of 20 C. or lower are excellent in abrasion resistance.

The invention relates to a tire having a rubber tread of a circumferentially zoned tread. The tread zones are comprised of three circumferential load bearing zones, with each zone containing a portion of the running surface of the tread, comprised of an intermedial rubber zone positioned between and extending beneath two stratified lateral tread rubber zones. The tread configuration contains an underlying carbon black-rich base rubber layer. The lateral tread rubber zones are therefore spaced apart from each other with the intermedial tread zone therebetween and also spaced apart from the tread base rubber layer with the intermedial tread zone therebetween. The intermedial and stratified lateral zones are comprised of rubber compositions having differentiated rebound physical properties.

A tire with radial carcass reinforcement comprising a crown reinforcement itself capped radially with a tread of which the tread pattern comprises at least two circumferential grooves. The tread is made up of at least three layers, a first layer forming the radially outer part of the tread of a first compound having an electrical resistivity per unit volume .sub.1 such that log(.sub.1) is less than 6, a second layer radially on the inside of at least three parts, at least the axially outer parts of a second compound having an electrical resistivity per unit volume .sub.2 such that log(.sub.2) is greater than 10, and at least part, radially extending the at least first elastomeric compound of the first layer, of a third elastomeric compound having an electrical resistivity per unit volume .sub.3 such that log(.sub.3) is less than 6, a third layer radially furthest towards the inside of at least five parts, at least the axially outer parts of a third elastomeric compound having a maximum value of tan(), denoted tan()max, of less than 0.080, at least two parts of the second compound, and at least part of the third layer, that radially extends the at least one part of the second layer of the third elastomeric compound.

The invention relates to a pneumatic tire comprising a carcass and a tread located radially outward of the carcass and extending between the tire sidewalls; the tread providing a radially outermost tread running surface; the tread comprising a first tread layer comprising a first rubber compound and a second tread layer comprising a second rubber compound; wherein the second tread layer is located radially adjacent to the first tread layer; wherein the first rubber compound is compositionally distinct from the second rubber compound; wherein the second tread layer comprises one or more integrally formed extensions of the second tread layer extending radially outwardly toward the tread running surface; wherein each of the integrally formed extensions of the second tread layer comprises a circumferentially continuous groove and a reinforcement zone disposed on a side of the groove; wherein the first rubber compound comprises 100 parts by weight of at least one diene based elastomer, and from 1 to 150 phr of silica; and the second rubber compound comprises a diene base elastomer, from 50 to 120 phr of a filler, wherein at least 20 phr of the filler is a high surface area carbon black having an iodine adsorption number of at least 100 g/kg, from 1 to 45 phr of a methylene acceptor, from 1 to 25 phr of a methylene donor, and from 1 to 30 phr of at least one additive selected from the group consisting of carbamic resins, liquid diene based polymers having a number average molecular weight ranging from 1000 to 25000, and aromatic hydrocarbon resins.

A pneumatic tire for a motorcycle includes a tread reinforcing cord layer and a tread rubber. The tread rubber includes a base rubber layer and a pair of shoulder rubber layers. The base rubber layer includes a cover portion covering at least the tread reinforcing cord layer over an entire width thereof and a convex portion protruding radially outwardly from the cover portion to form a crown ground contacting surface. The shoulder rubber layers are arranged radially outside the cover portion to form shoulder ground contacting surfaces. The base rubber layer is made of a first rubber composition having larger hardness than the shoulder rubber layers, and the shoulder rubber layers are made of a second rubber composition containing larger amount of oil component than the base rubber layer.

In a tire with a tread that includes tread pattern elements, a circumferential reinforcement, and first and second circumferential grooves, the circumferential reinforcement is formed of a rubber mixture having a stiffness greater than a stiffness of a rubber mixture forming a remainder of the tread. The tire has an outer side on one side of a median plane of the tire, and an inner side on an opposite side of the median plane. The first circumferential groove is disposed axially toward the outer side relative to the second circumferential groove. The circumferential reinforcement includes a reinforcing element having a tapered shape positioned in each of a group of the tread pattern elements disposed axially toward the outer side relative to one of the first and second circumferential grooves, with the reinforcing elements being axially close to an outer-side face of that circumferential groove.

A pneumatic tire including: on a tread of the tire, inclined belt layer and circumferential belt layer; and on the tread surface, a plurality of circumferential grooves extending in the tread circumferential direction, and shoulder land portions partitioned between the circumferential grooves located outermost in the tire width direction and tread ground contact ends. Positions of the tread surface that correspond to the outermost ends of the circumferential belt layer in the tire width direction are within the shoulder land portions, and the distance in the tire width direction between the outermost ends in the tire width direction of the circumferential belt layer and tire equator side ends of the shoulder land portions is 12% or more and 22% or less of a half of the width of the circumferential belt layer in tire width direction.

A pneumatic tire includes, on a tread surface, a plurality of circumferential main grooves extending in the tread circumferential direction, and a plurality of land portions defined by circumferential main grooves adjacent in the tread width direction among the plurality of circumferential main grooves, or by the circumferential main grooves and tread edges. A widthwise groove (widthwise sipe) (circumferential sipe) includes a widened portion, on the groove bottom side (sipe bottom side), at which the groove width (sipe width) is larger than on the tread surface side. In a tire radial direction region including at least a reference depth position, the storage modulus of first tread rubber, which is a groove wall surface layer defined by the widened portion and covering at least part of the widened portion, is larger than the storage modulus of second tread rubber located in a region around the first tread rubber.