Abstract: A method for manufacturing a pneumatic tire with a noise damper on the inside of the tread portion, comprises the steps of: building a raw tire on an annular tire building core; placing the raw tire within a vulcanizing mold together with the core; and heating the raw tire in the mold. The tire building core has a molding face for molding an inner surface of the tread portion. The molding face is provided with a groove extending in the tire circumferential direction. In the step of building the raw tire, an expandable damper material is placed in the groove. During heating the raw tire to be vulcanized, the damper material expands in the groove, whereby the expanded material forms the noise damper integrated into the radially inside of the tread portion.

Abstract: A pneumatic tire is provided with an electrically conductive path extending continuously from a position in the rim contacting surface to a position in the ground contacting surface through a sidewall portion, wherein a sidewall rubber is a high-performance rubber compound and almost-insulative, having a volume resistivity of not less than 1×10^8 ohm cm. The electrically conductive path includes a helical path made of an electrically conductive rubber having a volume resistivity of not more than 1×10^7 ohm cm. The helical path is disposed axially inside the sidewall rubber and extends spirally around the tire rotational axis. Preferably, the tread rubber, clinch rubber and carcass topping rubber are also almost-insulative high-performance rubber compounds.

Abstract: A rubber member for tires is formed by spirally winding an unvulcanized rubber strip. The rubber strip has a first longitudinal end portion for serving as a starting side of winding of the rubber strip and a second longitudinal end portion for serving as an end side of the winding. The end surface of at least one of the first end portion and the second end portion is an inclined surface inclining to the longitudinal direction line of the rubber strip.

Abstract: A pneumatic tire wherein at least 75% by weight of tire-constituting components based on the tire overall weight are made of nonpetroleum-based materials and wherein, at least, base rubber 2G2 and cap rubber 2G1 of tread rubber 2G, sidewall rubbers 3G and a topping rubber of carcass 6 are formed of an insulating rubber material, wing rubbers 2G3 of tread rubber 2G are formed of an electrically conductive rubber material, and sidewall portions are provided with at least one electrically conducting path 20 formed from a ribbon-like conductive rubber strip 21 made of an electrically conductive rubber material and having a width Ws of 10 to 40 mm, in which the conductive rubber strip 21 extends linearly in a radially inward direction from an electrically conducting part 21A contacting the wing rubber 2G3 to reach clinch rubber 4G.

Abstract: A pneumatic tire comprises a tread rubber comprising layers each formed by overlap winding a rubber tape. The rubber tape in each layer has a conductive part in the longitudinal direction of the tape and the remaining less-conductive part, wherein the conductive part is wound at least once around the tire. In the radially outermost layer, the conductive part is exposed in the tread surface by a total axial width WU of at least 1.0 mm. In the radially innermost layer, the conductive part appears in the radially inner surface so as to be electronically connected to a conductive underlying structure by a total axial width WL of at least 1.0 mm. Between the radially adjacent layers, the conductive part in the radially outer layer is connected to the conductive part in the radially inner layer by a total axial width WM of at least 1.0 mm. Preferably, the rubber tape is made of mainly a silica rich compound.

Abstract: A method for manufacturing a pneumatic tire with a noise damper on the inside of the tread portion, comprises the steps of: building a raw tire on an annular tire building core; placing the raw tire within a vulcanizing mold together with the core; and heating the raw tire in the mold. The tire building core has a molding face for molding an inner surface of the tread portion. The molding face is provided with a groove extending in the tire circumferential direction. In the step of building the raw tire, an expandable damper material is placed in the groove. During heating the raw tire to be vulcanized, the damper material expands in the groove, whereby the expanded material forms the noise damper integrated into the radially inside of the tread portion.

Abstract: A pneumatic tire is provided with an electrically conductive path extending continuously from a position in the rim contacting surface to a position in the ground contacting surface through a sidewall portion, wherein a sidewall rubber is a high-performance rubber compound and almost-insulative, having a volume resistivity of not less than 1×10ˆ8 ohm cm. The electrically conductive path includes a helical path made of an electrically conductive rubber having a volume resistivity of not more than 1×10ˆ7 ohm cm. The helical path is disposed axially inside the sidewall rubber and extends spirally around the tire rotational axis. Preferably, the tread rubber, clinch rubber and carcass topping rubber are also almost-insulative high-performance rubber compounds.

Abstract: A method of manufacturing a vehicle tire comprises: making a rubber tire component by winding at least one unvulcanized rubber tape; making a green tire by assembling components including the rubber tire component; and vulcanizing the green tire, wherein the unvulcanized rubber tape is a hybrid rubber tape made of a high-performance rubber composition and a conductive rubber composition, and the conductive rubber composition forms a surface layer forming at least a part of the surface of the hybrid rubber tape. The conductive rubber composition of the windings of the hybrid rubber tape extends across the cross section of the tire component, whereby in the vulcanized tire, an electrostatic dissipative path is formed by the conductive rubber composition.