Provided are a rubber composition for tires that shows a balanced improvement in properties such as fuel economy, processability, heat aging resistance, abrasion resistance, wet-grip performance, performance on snow and ice, and handling stability, and a pneumatic tire formed from the rubber composition. The present invention relates to a rubber composition for tires, containing: a highly purified, modified natural rubber having a pH adjusted to 2-7; carbon black and/or a white filler; and a silane coupling agent represented by the following Formula (S1): ##STR00001##
wherein R.sup.1001 represents a monovalent group selected from —Cl, —Br, —OR.sup.1006, —O(O═)CR.sup.1006, —ON═CR.sup.1006R.sup.1007, —ON═CR.sup.1006R.sup.1007, —NR.sup.1006R.sup.1007, and —(OSiR.sup.1006R.sup.1007).sub.h(OSiR.sup.1006R.sup.1007R.sup.1008), wherein R.sup.1006, R.sup.1007, and R.sup.1008 are the same as or different from one another and each represent a hydrogen atom or a C1-C18 monovalent hydrocarbon group, and h represents a number whose average value is 1 to 4; R.sup.1002 represents R.sup.1001, a hydrogen atom, or a C1-C18 monovalent hydrocarbon group; R.sup.1003 represents R.sup.1001, R.sup.1002, a hydrogen atom, or the group: —[O(R.sup.1009O).sub.j].sub.0.5— wherein R.sup.1009 represents a C1-C18 alkylene group, and j represents an integer of 1 to 4; R.sup.1004 represents a C1-C18 divalent hydrocarbon group; R.sup.1005 represents a C1-C18 monovalent hydrocarbon group; and x, y, and Z are numbers satisfying the following relationships: x+y+2z=3, 0≦x≦3, 0≦y≦2, and 0≦z≦1.

A motorcycle tire includes a tread portion, a carcass, a breaker layer disposed outside the carcass with cords oriented at an angle equal to or more than 15 degrees with respect to a tire equator, and a tread rubber disposed outside the breaker layer so as to form a band-less structure in which the tread rubber is arranged so as to be directly in contact with the breaker layer. The tread rubber includes a cap rubber layer forming a ground contacting surface of the tread portion, and a base rubber layer disposed inside the cap rubber layer and having complex modulus greater than that of the cap rubber layer. The base rubber layer extends between a pair of outermost ends thereof so as to across the tire equator, and a thickness of the base rubber layer at the tire equator is greater than that of the outermost ends.

A tire comprises a directional tread (10), said tread comprising a central axis (12) and two edges (14A, 14B) a tread width W being greater than or equal to 140 mm, said tread (10) comprising a plurality of patterns (13) which succeed one another in the circumferential direction, each pattern having a pitch P, the patterns (13) delimiting a plurality of oblique grooves (16A, 16B), each oblique groove extending from one of the edges (14A, 14B) of the tread as far as the central axis (12). In a central part of the tread centered on the central axis (12) and of a width corresponding to 80% of the width W of said tread, all or some of the oblique grooves (16A, 16B) of the plurality of oblique grooves have a prescribed slenderness ratio, and all or some of the patterns comprise at least one sipe and have a prescribed sipes density SD.

Modified thermoplastic hydrocarbon thermoplastic resins are provided, as well as methods of their manufacture and uses thereof in rubber compositions. The modified thermoplastic resins are modified by decreasing the relative quantity of the dimer, trimer, tetramer, and pentamer oligomers as compared to the corresponding unmodified thermoplastic resin polymers, resulting in a product that exhibits a greater shift in the glass transition temperature of the elastomer(s) used in tire formulations. This translates to better viscoelastic predictors of tire tread performance, such as wet grip and rolling resistance. The modified thermoplastic resins impart remarkable properties on various rubber compositions, such as tires, belts, hoses, brakes, and the like. Automobile tires incorporating the modified thermoplastic resins are shown to possess excellent results in balancing the properties of rolling resistance, tire wear, snow performance, and wet braking performance.

A tire with a radial carcass reinforcement, having a crown reinforcement, itself capped radially by a tread connected to two beads by two sidewalls, the tread having at least two layers of blended elastomeric compounds that are radially superposed and have a voids ratio that is lower in the central part than at the axially outer parts. A first layer of blended elastomeric compounds of the tread is made up of a first blended elastomeric compound forming a part extending at least into the region of the equatorial plane and of at least two axially outer parts formed of a second blended elastomeric compound, the first blended elastomeric compound having a macro dispersion Z-value higher than 65 and a maximum tan(δ) value, denoted tan(δ)max, lower than 0.120, and the complex dynamic shear modulus G* 1% at 100° C. of the second blended elastomeric compound having a value at least 10% higher than that of the complex dynamic shear modulus G* 1% at 100° C. of the first blended elastomeric compound.

The invention relates to a tire provided with a tread, said tread comprising a rubber composition based on at least one diene elastomer, a zinc diacrylate derivative in the form of a zinc salt in which R1, R2 and R3 independently represent a hydrogen atom or a C1-C7 hydrocarbon group selected from linear, branched or cyclic alkyl groups, aralkyl groups, alkylaryl groups and aryl groups, which are optionally interrupted by one or more heteroatoms, R2 and R3 being able to form together a non-aromatic ring, and a peroxide. The contents of zinc diacrylate derivative and peroxide are such that the ratio of the peroxide content to the zinc diacrylate derivative content is less than or equal to 0.09, said composition comprising no reinforcing filler or comprising less than 50 phr thereof, the ratio of the filler content to the zinc diacrylate derivative content being less than or equal to 2.

Rubber compound for the preparation of a tread portion of a pneumatic tyre comprising at least a cross-linkable unsaturated chain polymer base, a filler and a vulcanization system and a wax composed of at least 50% by weight of nonacosanediols.

A conjugated diene polymer satisfying following conditions (1) to (4): (1) the conjugated diene polymer has two or more peaks in a molecular weight distribution curve obtained by measurement with gel permeation chromatography (GPC); (2) the molecular weight distribution curve contains a peak (A) having a peak molecular weight of 500,000 to 2,500,000 and a peak (B) having a peak molecular weight of 150,000 to 600,000; (3) a total value of an area of the peak (A) and an area of the peak (B) is 70% or more of a total area of the molecular weight distribution curve; and (4) an absolute value of difference between a glass transition temperature of a conjugated diene polymer in the peak (A) (Tg (A)) and a glass transition temperature of a conjugated diene polymer in the peak (B) (Tg (B)) is 2° C. to 30° C.

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 a silica-rich intermedial rubber zone positioned between and extending beneath two carbon black-rich lateral tread zones. The tread configuration contains an underlying carbon black-rich base rubber layer. The intermedial and stratified lateral zones are comprised of rubber compositions having differentiated rebound physical properties. A path of least electrical resistance extends from a lateral carbon black-rich rubber tread zone to the carbon black-rich tread base layer by an extension of a lateral tread zone or by an intermediate carbon black-rich rubber bridge.

The present invention is directed to a pneumatic tire comprising a tread, the tread comprising a rubber composition comprising a solution polymerized styrene-butadiene rubber; a first polybutadiene rubber comprising at least 90 percent by weight of monomer units in cis-1,4 configuration; a second polybutadiene rubber comprising at least 70 percent of monomeric units in syndiotactic-1,2 configuration and having a melting point temperature ranging less than 150° C. as measured by ASTM D3418; and a pre-hydrophobated precipitated silica wherein the pre-hydrophobated precipitated silica is hydrophobated prior to its addition to the rubber composition by treatment with at least one silane selected from the group consisting of alkylsilanes, alkoxysilanes, organoalkoxysilyl polysulfides and organomercaptoalkoxysilanes and optionally at least one dispersing aid selected from the group consisting of fatty acids, diethylene glycols, polyethylene glycols, fatty acid esters of hydrogenated or non-hydrogenated C.sub.5 or C.sub.6 sugars, polyoxyethylene derivatives of fatty acid esters of hydrogenated or non-hydrogenated C.sub.5 or C.sub.6 sugars.