A tire comprises a tread portion 2. The tread portion 2 includes a tread ground contacting surface (2s) and at least one main groove 3 recessed from the tread ground contacting surface (2s) and extending continuously in a tire circumferential direction. The main groove 3 has a first groove wall 11. The first groove wall is provided with a recessed portion 15 recessed outwardly in a groove width direction from a groove edge of the main groove 3 on the tread ground contacting surface. The recessed portion 15 is formed of groove wall rubber 8 having a complex elastic modulus larger than that of base rubber 7 forming a main portion of the tread ground contacting surface (2s).

A method for forming a composite tread, the method comprising the steps of: forming a coextruded strip of a first compound and a second compound, wherein the first compound is a tread compound, and the second compound is formed from a second compound, wherein the tread is formed from winding the coextruded strip onto the tire building drum while varying the ratio of the first compound to the second compound

In a tire, a tread includes a cap layer forming a part of an outer surface of the tire, a base layer disposed inwardly of the cap layer in a radial direction, and an intermediate layer disposed between the cap layer and the base layer in the radial direction. A loss tangent of the intermediate layer at 30° C. is less than a loss tangent of the cap layer at 30° C. and a loss tangent of the base layer at 30° C. is less than the loss tangent of the intermediate layer at 30° C. The tread includes at least two three-layer body portions formed of the cap layer, the intermediate layer, and the base layer, and at least one two-layer body portion that is formed of the cap layer and the base layer and disposed between a first three-layer body portion and a second three-layer body portion.

A method for forming a composite tread is described, wherein the method includes the steps of selecting a first tread compound having a first desired tread property, and selecting a second tread compound having a second desired property, forming a tread by winding a dual layer strip having a first layer formed of the first tread compound and a second layer formed of the second compound, wherein the tread has a first and second zone, wherein each zone is formed by spirally winding the dual layer strip, wherein the first zone is formed of a dual layer strip having a strip ratio of the volumetric proportion of the first compound to the second compound used to form the dual layer strip, wherein the second zone has a different strip ratio than the first zone by varying the volumetric proportion of the first compound to the second compound.

A tire having a tread, wherein the tread has an outer shoulder region and an inner shoulder region, wherein each shoulder region is formed from a dual layer strip having a first layer formed of a first compound, and a second layer formed of a second compound, wherein the dual layer strip has a strip ratio of % first compound/% second compound, wherein the outer shoulder region has a strip ratio in the range of 70-95% of the first compound/5-30% of the second compound.

A tire having a tread comprising at least one circumferential reinforcing element 8 of which at least part of the meridional cross section has the shape of a triangle, the vertex of which is oriented radially towards the outside, the circumferential reinforcing element 8 comprising a skin 81 and a core 82, the skin material being at least twice as stiff as the core material.

The invention is a tire comprising a crown comprising at least one layer of reinforcing elements. The radially outermost layer comprises at least one undulation (512). The undulations (512) in the radially outermost layer (5) are such that the points of the undulations are radially on the outside of the points of said layer (5) that are vertically beneath the centre of the bottom face (243) of the closest major groove (24) by at least a radial distance of 1.5 mm. The undulations (512) in the radially outermost crown layer make up at least 10% of the radially outer surface (ROS) of said crown layer (5). A rubber compound with a dynamic modulus G*, measured at 40° C. at 10% peak-to-peak strain at 10 Hz, that is at most equal to 3.25 MPa, makes up at least 30% of the rubber compounds vertically above said undulations.

An article of manufacture comprising: (a) a body at least a portion of which is a multi-phase material (MPM) defining a traction surface; (b) the MPM comprising at least first and second zones comprising first and second materials, M1, M2, respectively, at or near the traction surface, the M1 and M2 having first and second Young moduli respectively, the first and second moduli differing by at least a factor of 3; and (c) wherein each of the second zones has a center, and wherein the second zones have a center-to-center radial distribution function having a peak at between 10 μm and 10 mm.

Materials make it possible to generate mechanical coupling in elastomeric compositions, of use especially for the manufacture of tyre treads. In particular, a tread comprises a composite material based on an elastomeric matrix, a crosslinking system, a reinforcing filler and oriented short fibres.

A non-pneumatic tire for a vehicle or other machine. The non-pneumatic tire may comprise an annular beam. The annular beam may comprise a plurality of layers of different elastomeric materials. The annular beam may be free of a substantially inextensible reinforcing layer running in a circumferential direction of the non-pneumatic tire. The annular beam may comprise a plurality of openings distributed in the circumferential direction of the non-pneumatic tire. Such an annular beam may be part of other annular devices.