A tire comprises a tread which comprises a plurality of tread pattern elements (1) delimited by cut-outs (3, 4), the tread pattern elements respectively comprising at least one lateral face (13, 14, 15, 16), and a first rubber composition (FC) at least partially covered on at least one of the lateral face (13, 14, 15, 16) with a layer of a second rubber composition (SC) based on an elastomer matrix comprising more than 55 phr and up to 100 phr of a first diene elastomer having a glass transition temperature of less than ?25? C. and 0 to less than 45 phr of a second diene elastomer, a reinforcing filler comprising more than 100 phr of a reinforcing inorganic filler, and more than 45 phr of a plasticizing agent predominately comprising at least one hydrocarbon resin having a glass transition temperature of more than 20? C.

In a first aspect of the present invention, a tire tread is provided, the tread comprising a tread cap comprising a first rubber compound for contacting the road when driving, at least one circumferential groove reinforcement forming at least one of the grooves in the tread cap, the groove reinforcement comprising a second rubber compound for reinforcing an area adjacent the grooves formed by the groove reinforcement, wherein the groove reinforcement comprises for at least one of the grooves formed by the groove reinforcement two groove sidewall layers, each sidewall layer extending from the outer radial surface of the unworn tread down into the direction of the bottom of the groove formed by the groove reinforcement and wherein each sidewall layer has an essentially uniform thickness along its length, and wherein the groove reinforcement comprises a groove support portion forming a bottom portion of the groove and having a radially inner base side as well as a radially outer top side, wherein the groove support portion tapers from its base side to its top side.

The present invention provides a method for surface-modifying a rubber vulcanizate or a thermoplastic elastomer, which can cost-effectively provide a variety of functions, such as remarkable sliding properties or biocompatibility, according to the application. The present invention relates to a method for surface-modifying a rubber vulcanizate or a thermoplastic elastomer as a modification target, the method including: step 1 of forming polymerization initiation points A on a surface of the modification target; step 2 of radically polymerizing a non-functional monomer starting from the polymerization initiation points A to grow non-functional polymer chains; step 3 of washing the modification target on which the non-functional polymer chains are grown; step 4 of forming polymerization initiation points B on a surface of the non-functional polymer chains; and step 5 of radically polymerizing a fluorine-containing functional monomer starting from the polymerization initiation points B to grow fluorine-containing functional polymer chains.

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 tire includes a circumferential tread constructed of a base material. The circumferential tread has a plurality of bars, each of the plurality of bars having a top surface and a plurality of side surfaces. The circumferential tread further has a plurality of valleys disposed between the plurality of bars. A reinforcement layer covers at least some of the plurality of valleys and an outer layer covers at least a portion of the reinforcement layer.

A tire is provided with a tread that includes first and second sectors and grooves. The second sectors are formed of a rigid reinforcing compound. Each of the first and second sectors has a contact face intended to contact a road surface when the tire is in use. Each groove includes sidewalls and a bottom, and extends from an end of an adjacent contact face. A depth P of each groove is measured in a radial direction between its bottom and a position corresponding to a radial height of the adjacent contact face. At least one of the second sectors has a contact face that includes a recess having a depth p of less than 2 mm, as measured in a radial direction from a surface of the recess to a position corresponding to a radial height of an adjacent first sector.

Tire (1) for a heavy vehicle of construction plant type with tread (2) comprising raised elements (3), separated by grooves (4), extending radially outwards from a bottom surface (5) as far as a contact face (6) over a height (H) and comprising base compound (9) and coating compound (10). Coating compound (10) has a constant maximum thickness (e.sub.max), at the contact face (6) of each raised element (3), at most equal to 0.15 H, the coating compound (10) has a constant minimum thickness (e.sub.min), at each groove bottom (8), at least equal to 0.04 H, and the elongation at break at 23 C. A.sub.R2 of the coating compound (10) is at least equal to 1.05 times the elongation at break of 23 C. A.sub.R1 of the base compound (9).

A tread for a pneumatic tire includes tread pattern elements and cuts. Each tread pattern element includes lateral faces and a contact face that comes into contact with a road surface when the tire is being driven thereon. A boundary between the contact face and the lateral faces forms at least one edge corner. The cuts are formed as grooves and/or sipes, with the cuts being delimited by opposing lateral faces of the tread pattern elements. Each tread pattern element is formed of at least one rubber compound. When the tread is viewed in cross section in a plane normal to an axis of rotation of the tire and passing through a contact face of a tread pattern element, at least one of the cuts adjacent to that contact face is covered at least in part with a covering layer that contains a woven or nonwoven fiber assembly.

A tread made of rubber material for a snow tire having a tread surface intended to be in contact with a road surface when the tire is being driven on, and provided with a plurality of cuts delimited by walls situated facing one another and forming lateral walls of raised elements of the tread. Each lateral wall intersects the tread surface to form an edge corner. At least one lateral wall of a raised element is formed partially or fully by a cover layer extending from the edge corner associated with this lateral wall, of a material having an elastic modulus higher than that of the rubber material of the tread. The raised element has a depression in its lateral wall, delimited by the cover layer. The raised element moreover has a width W and the depth P of the depression is at least equal to 10% of the width W of the element and less than or equal to 40% of this width W. Finally the volume of the depression is less than 10% of the volume of the raised element.

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.