The present invention provides a pneumatic tire in which a steel cord carcass ply composed of an ultrafine wire having a filament diameter of 0.15 mm or less is used as a reinforcing material, and the carcass ply is positioned between the bead cords without turn-up of the carcass ply for turning up it through an annular bead bundle on an upper side of the carcass ply, such that side rigidity is maintained even when replacing two conventional fiber carcass plies with one steel carcass. Thereby, rather than the conventional turn-up method of turning up the carcass ply on the upper side of the annular bead bundle, the carcass ply passes through the bead bundles as shown in FIG. 3, such that a deformation energy of the bead portion is minimized and a rolling resistance is maximized. The tire of the present invention is characterized by satisfying a correlation equation between a height Bh1 of an inner bead bundle position and a height Ah of the bead portion including an apex of 1.2<Ah/Bh1<4.5.

The present invention relates to a self-supporting tire for vehicle wheels comprising a carcass structure comprising at least one carcass ply having a plurality of hybrid reinforcing cords (10) each comprising at least two strands (20) twisted to each other with a predetermined stranding pitch (P), wherein each of said at least two strands (20) comprises at least one monofilament textile thread (21) at least partially embedded in the filaments (22a) of at least one multifilament textile yarn (22) and a pair of sidewall reinforcement inserts (113), where at least one of said sidewall reinforcement inserts comprises a vulcanised elastomeric compound which has a dynamic shear modulus value G equal to or less than 1.25 MPa measured at 70° C., 10 Hz, 9% deformation according to the RPA method reported in the present description.

In a pneumatic tire in which a reinforcing layer including a cord is embedded, a coating rubber covering the cord included in the reinforcing layer uses a rubber composition in which 30 parts by mass to 60 parts by mass of carbon black having a nitrogen adsorption specific surface area N.sub.2SA of 100 m.sup.2/g or more and 0 parts by mass or more and 10 parts by mass or less of aroma oil is optionally blended, per 100 parts by mass of a rubber component containing 70 mass % to 100 mass % of a natural rubber and in which a strength at break TB (unit: MPa) at 100° C. and a stress M100 (unit: MPa) at 100% elongation at 100° C. satisfy a relationship TB.sup.2/M100≥50.0.

Provided is a heavy-duty pneumatic tire in which not only occurrence of a damage of CBU but also occurrence of pulling-out of a carcass ply can be inhibited, and which has excellent durability. In the tire, beads each include a cover enclosing at least a part of a core. The cover is located, between the core and the carcass ply, in a portion at which the carcass ply encloses the core. The cover is composed of one cover ply including a large number of aligned cover cords and a cover topping rubber covering the cover cords. A ratio of a distance between the cover cords to an outer diameter of a carcass cord is not lower than 0.35 and not higher than 0.85. A difference between a hardness of the cover topping rubber and a hardness of a carcass topping rubber is not less than −5 and not greater than 5.

In a pneumatic tire, an elongation at break (EB) of carcass cords constituting a carcass layer satisfies a condition of EB≥15%. A tread portion includes a pair of center main grooves each extending in a tire circumferential direction with a tire equator line interposed therebetween, and a center land portion defined by the pair of center main grooves. A ratio (Wc/Wb) of a width (Wc) of the center land portion to a width (Wb) of a widest belt within a belt layer in the tire width direction satisfies a condition of 0.10≤Wc/Wb≤0.20. An elongation at break (EB) of the carcass cords and the ratio (Wc/Wb) of the width (Wc) of the center land portion to the width (Wb) of the widest belt satisfy a condition of 350≤10×1/(Wc/Wb)+20×EB≤900.

A pneumatic tire is provided. A carcass layer includes carcass cords formed of organic fiber cords obtained by intertwining a filament bundle of organic fibers, and includes turn-up portions formed by turning up end portions of a pair of bead portions to an outer side in a tire width direction. The carcass cords have an elongation at break (EB) satisfying EB≥15%. A portion of a belt layer located in a width range of 10% of a width of a second widest belt in the belt layer on each of a left side and a right side of a tire equator line in a tire width direction has a belt angle (θc) satisfying 0.349 rad≤θc≤0.56 rad. The elongation at break (EB) of the carcass cords and the belt angle (θc) satisfy 800<1140×θc+20×EB<1400.

A carcass layer of a pneumatic lire includes carcass cords of organic fiber cords obtained by intertw ining a filament bundle of organic fibers, and includes turn-up portions formed by turning back end portions of the carcass layer at bead portions toward an outer side in a width direction. The carcass cords have an elongation at break (EB) satisfying EB≥15%. An averagetotal gauge (GC)of a center land portion located within a width of 10% of a width of a second widest belt in a belt layer on right and left sides of an equatorial plane in the width direction, an average thickness(SG) of a sound absorptive member inside the pneumatic tire and located within a range identical to that of the center land portion, and the elongation at break (EB) of the carcass cords satisfy 15≤GC/(GC+SG/10)×EB (%)≤25.

This invention relates to an adhesive composition for a tire cord, a tire cord including an adhesive layer formed from the adhesive composition, and a tire including the tire cord. According to the present disclosure, an environment-friendly adhesive composition for a tire cord that can not only improve adhesive strength between tire rubber and a tire cord, but can also improve strength of a tire cord is provided.

This invention relates to an adhesive composition for a tire cord including: an epoxy compound; latex; an alicyclic polyurethane resin having a weight average molecular weight (Mw) of 250,000 to 350,000; an amine compound; and water, a tire cord including an adhesive layer formed form the adhesive composition, and a tire including the tire cord.

A pneumatic tire includes at least one carcass layer between bead portions on an inner side in a radial direction of sidewall portions on both sides of a tread portion extending in a circumferential direction and having an annular shape, and the carcass layer includes carcass cords formed of organic fiber cords obtained by intertwining a filament bundle of organic fibers. The carcass layer includes turn-up portions formed by being turned back at an end portion of the bead portions to an outer side in a tire width direction. The carcass cords have an elongation at break EB satisfying EB≥15%, a cap tread rubber compound of the tread portion has a 300% modulus MD satisfying 4 MPa≤MD≤13 MPa, and the elongation at break EB and the 300% modulus MD satisfy 600≤40×MD+20×EB (%)≤1300.