The present invention is directed to a pneumatic tire comprising a tread portion having (i) circumferential grooves and (ii) circumferential ribs or rows of tread blocks; an inner surface defining a tire cavity; and a sealant material layer at least partially covering the inner surface radially below the tread portion within the tire cavity. The sealant material layer comprises elevations of sealant material, wherein an elevation of sealant material is provided radially below each of at least two of the circumferential grooves, and wherein the sealant material layer has a larger radial thickness in said elevations than in areas radially below the circumferential ribs or rows of tread blocks.

A pneumatic tire is provided where a profile line in a tire meridian cross section of a center land portion defined by circumferential grooves and located on a tire equator is curved projecting outward in a tire radial direction. A carcass layer and a reinforcing layer include a recess portion curved projecting inward in the tire radial direction in a bottom region of the center land portion.

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, wherein the angle of the low angle belt is less than 5 degrees. The working belts and the low angle belt are extensible, and preferably made of high elongation wire. The pneumatic tire further includes a wherein the tread is formed of a treadcap compound having a tensile at break greater than 18 MPa, and an elongation at break greater than 450%.

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.

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.

A pneumatic radial tire is provided that includes belt layers disposed on an outer circumferential side of a carcass layer in a tread portion, and a belt cover layer disposed on an outer circumferential side of the belt layers, the belt cover layer including organic fiber cords helically wound along a tire circumferential direction, the belt layers including steel cords arranged at an incline with respect to the tire circumferential direction in such a manner as to intersect one another between the layers, each of the belt layers having a bending rigidity of 16500 N.Math.mm.sup.2/.sub.50 mm or less per 50 mm width in a direction orthogonal to a longitudinal direction of the steel cords, and the belt cover layer including organic fiber cords having an elongation of 2.0% to 4.0% under a load of 2.0 cN/dtex, the organic fiber cords being helically wound along the tire circumferential direction.

The bead portion of a pneumatic tire has a bead structure including a bead core having a bead cord covered with a resin material, and a bead filler continuous to the bead core and formed of the resin material and tapered outside in the tire radial direction. The bead structure has a weld line of the resin material. The weld line is formed inside in the tire radial direction more than ⅔ of the total height along the tire radial direction of the bead structure.

A pneumatic tire comprises a mesh reinforcing layer formed from a tape wound circumferentially of the tire plural turns while repeating a zigzag unit comprising two inclined portion so that a number N of the repeated zigzag units are arranged while shifting in the tire circumferential direction and partly overlapping with each other. The amount of positional shift between the circumferentially adjacent zigzag units is in a range from 0.7 to 1.3 times a value of 360/N in terms of the angle α around the tire rotational axis.

The run flat tire includes a tread portion in contact with a road surface, a tire side portion continuous to the tread portion and positioned inside in the radial direction of the tread portion, and a carcass forming a tire skeleton. The run flat tire is provided with a side reinforcing rubber in tire side portion. A carcass reinforcing belt formed by covering a circumferential direction cord extending along tire circumferential direction with a rubber material and a sheet-like reinforcing layer formed of a resin material are provided in layers on an inner side of the tire radial direction of the tread portion.