Abstract: A pneumatic tire for a passenger car having a pair of bead portions, a toroidal carcass portion extending over both bead portions, at least two belt layers provided in a crown portion of the carcass, a tread portion positioned at an outer peripheral side of the belt layer, and side wall portions provided at the right and left sides of the tread portion, and which further includes a steel cord as a reinforcing material for reinforcing at least one layer of the carcass portion and the belt layer. The steel cord is formed by plying a plurality of filaments each having a strand diameter of 0.125 to 0.275 mm, and has an inflection point on an S—S curve. A reduction rate of a diameter of the steel cord under a load stress which is one third of breaking strength in comparison with a no load condition is equal to or more than 20%.

Abstract: There is disclosed a safety pneumatic tire comprising a tire shell which is equipped with a toroidal carcass extending over a pair of bead portions and also functioning as a reinforcing material for a side wall portion connected to the bead portions and further for a tread portion, and which has a side-reinforcing layer on the internal surface of the side-wall portion; a rim which hermetically seals and supports the bead portions of the tire shell; and closed cell-based elastic foam which is filled in the internal hollow portion encompassed by the tire shell and the rim, wherein the constructional material of the elastic foam is butyl rubber or halogenated butyl rubber. The above safety pneumatic tire is markedly improved in run-flat durability, can reconcile favorable riding comfort chacteristic with the run-flat durability, is minimized in adverse influence upon the tire performances such as rolling resistance, and enables the production of a lightweight pneumatic tire.

Abstract: A pneumatic tire comprises a carcass of at least one rubberized ply of a radial arrangement, a belt comprised of two or more cross cord layers, a pair of thick reinforcing strip rubbers located at an inner face side of the carcass and a bead filler rubber, in which the reinforcing strip rubber and bead filler rubber have specified JIS hardness and rebound resilience, hardness ratio and maximum gauge ratio.

Abstract: In a pneumatic tire for run-flat running comprising a stiffener rubber, viewing a cross-section of the tire-rim assembly inflated under an air pressure corresponding to 15% of a maximum air pressure of the tire, a top of the stiffener rubber is located inward from a specified line segment PA in a radial direction of the tire.

Abstract: A pneumatic tire comprising a toroidal carcass, a belt composed of at least two rubberized cord layers arranged radially outside the carcass, and a tread surrounding the periphery of the belt. The tread rubber comprises a base rubber made of a foamed rubber, and a cap rubber made of a non-foam rubber. The cap rubber is arranged radially outside the base rubber.

Abstract: A pneumatic radial tire includes a belt layer consisting of a plurality of belt plies reinforced by cords. The cords of at least two adjacent belt plies are oblique in opposite directions with respect to an equatorial plane of the tire. The tire comprises a relieving ply overlapping the belt plies. A modulus of the relieving ply is less than that of the belt plies. A width of the relieving ply is wider than that of the belt ply having the widest width. Cords reinforcing the relieving ply is oblique with respect to the equatorial plane in the same directions as those of cords of the belt ply having the widest width. Separations at belt ends of the maximum width belt ply is effectively prevented.

Abstract: A pneumatic tire for use in passenger cars is disclosed, which comprises a carcass as a reinforcement for a tire casing and a belt composed of two parallel-arranged belt layers each containing steel cords therein, the cords of which layers being crossed with each other with respect to the mid-circumferential line of the tire. In this tire, the belt is composed of a combination of a rubberized layer containing flexible and stretchable steel cords of strand construction in the same direction, each cord having a bending resistance of 5.about.1.4 gf/mm as a ratio of load to unit deflection under loading in three-point bending test and an elongation under a load of 3 kgf of 0.5.about.2% in tension test, and a layer and/or a cap composed of textile cords surrounding an outer periphery of each of at least both side ends of the rubberized layer.