A heavy-duty tire comprises a tread reinforcing belt comprising first to fourth belt plies each composed of belt cords inclined with respect to the tire equatorial plane. The first radial distance L1 between the belt cords of the third belt ply and the belt cords of the fourth belt ply is not more than the second radial distance L2 between the belt cords of the second belt ply and the belt cords of the third belt ply. The cord count E4 of the fourth belt ply is smaller than the cord count E3 of the third belt ply.

The present invention relates to a tire cord having excellent durability while being thin in thickness, a manufacturing method thereof and a tire comprising the same.

Protective reinforcement (3) for a tire has a mean radial thickness T at least equal to two times the diameter D of a −12-reinforce (4), comprises respectively on its radially interior face (31) and on its radially exterior face (32) parts (7) made of elastomeric compound having an axial width W at least equal to the diameter D of a −12-reinforcer (4), and the path of any −12-reinforce (4), in the circumferential direction (XX′), varies radially between the radially interior first face (31) and the radially exterior second face (32), in such a way that the set of paths of the reinforcers (4) of the protective reinforcement (3) constitutes a three-dimensional lattice. Furthermore, the path of any −12-reinforce (4), in the circumferential direction (XX′), is a zigzag curve extending axially over the entire axial width L of the protective reinforcement (3).

To provide a rubber compound for tires, a pneumatic tire and an airless tire capable of improving the steering stability of the tire while exerting excellent low fuel consumption performance. A rubber compound for tires characterized in that, of vulcanized rubber's physical properties, a complex elastic modulus E*.sub.70 (unit: MPa) and a loss tangent tanδ.sub.70 under initial strain of 10%, dynamic strain of 2% and temperature of 70 degrees C., satisfy 90<E.sub.70<250, and E*.sub.70/tan δ.sub.70>800. A pneumatic tire provided with a rubber member made of the above-mentioned rubber compound. An airless tire provided with a rubber member made of the above-mentioned rubber compound. An airless tire provided in a tread ring with a shear rubber layer made of the above-mentioned rubber compound.

A pneumatic tire is provided in the tread portion 2 with a belt 7 comprising a radially outermost first belt ply 7A and a radially inner second belt ply 7B each composed of belt cords 7C, and a band 8 thereon comprising a band ply 8A compound of a band cord 8C. At least one of axially outer edge portions of the belt 7 is provided between the first belt ply 7A and the second belt ply 7B with a first reinforcing rubber layer 11 having a radially outer surface which is convexed radially outwardly and along which an axially outer edge portion 15 of the first belt ply 7A extends in a mountain shape so as to have an axially inner portion 15a extending axially outwardly and obliquely toward the band ply 8A and an axially outer portion 15b extending axially outwardly and obliquely away from the band ply 8A.

In a pneumatic tire, a belt cover layer is provided on an outer circumferential side of a belt layer in a tread portion and includes organic fiber cords helically wound along a tire circumferential direction. As the organic fiber cord, a polyethylene terephthalate fiber cord is used which has a single yarn size fineness of 700 dtex or less and in which the number of twists is 30 twists or more/100 mm. A layer thickness of the belt cover layer is 1.6 times or more as large as a cord diameter of the organic fiber cord.

The present invention aims to provide a pneumatic tire with sufficiently reduced rolling resistance. The pneumatic tire according to the present invention including a carcass having a carcass main portion extending from a tread portion via a sidewall portion to a bead portion in a toroidal shape and locked on a bead core embedded in the bead portion, and a belt disposed on a crown portion outer peripheral side of the carcass, characterized in that, when mounted on an applicable rim and put under a predetermined internal pressure no-load condition, a minimum value R1 of a curvature radius of a tire width direction cross-section in a tire radial direction outer portion of the carcass main portion positioned on an tire radial direction outer side than a position where a distance measured from a tire radial direction inner end of the carcass outwardly in the tire radial direction becomes ½ of a carcass cross-sectional height is 0.6 times or less of a minimum value R2 of the curvature radius of the tire width direction cross-section of a portion that, in the tire radial direction inner portion of the carcass main portion positioned on the tire radial direction inner side than the tire radial direction outer portion, bulges out in the tire width direction.

A pneumatic tire for use on trucks, the tire comprising: a tread which includes a belt reinforcement structure, the belt structure including a pair of working belts, wherein the angle of the working belts range from about 10 degrees to about 50 degrees, and wherein the first working belt has an angle of the reinforcements different that the angle of the belt reinforcements of the second working belt. The belt package further includes a low angle belt that is preferably positioned between of the working belts. The pneumatic tire further includes a tread having a groove reinforced with a tread compound having a tensile at break greater than 18 MPa, and an elongation at break greater than 450%.

In a pneumatic tire, a tread average thickness A in a tire width direction region of a center land portion where a center cover layer is disposed, a tread average thickness B in a tire width direction region of the center land portion where the center cover layer is not disposed, and a tread average thickness C in tire width direction regions where second land portions located further on an outer side than the center land portion in a tire width direction and adjacent to the center land portion are defined and formed satisfy a relationship A<B<C.

The present invention provides a tire that uses an elastomer-metal cord composite, which composite is obtained by coating metal cords with an elastomer, each metal cord being composed of a bundle of metal filaments arranged without being twisted, and which composite is capable of highly improving the performance of the tire. The above described tire is one including a belt (105) which includes at least two belt layers (105a) and (105b). In this tire, the belt layers (105a) and (105b) are each obtained by coating metal cords (2) with an elastomer (3), each metal cord (2) being composed of a bundle of a plurality of metal filaments (1) arranged in a row without being twisted; at least one pair of adjacent metal filaments in the metal cord (2) differ in at least one of the amount of shaping and shaping pitch; each of the belt layers (105a) and (105b) has a thickness t1 of more than 0.30 mm and less than 1.00 mm; and the distance g in the tire radial direction between the metal cords (2) in the two adjacent belt layers (105a) and (105b) is 0.10 mm or more and 1.20 mm or less at the center of the tire.