Abstract: A pneumatic tire includes a block defined by first and second main grooves and first and second lateral grooves, wherein the block includes a slit having one end open to the first main groove and the other end terminating in the block, a first corrugated sipe having one end open to the first main groove and the other end terminating in the block, and a second corrugated sipe having one end open to the second main groove and the other end terminating in the block, the slit includes a notch groove and a center sipe, the center sipe includes a first portion extending from the notch groove toward the second main groove, and a second portion bent and extending from a terminal end of the first portion, and the first and second corrugated sipe are disposed in the tire circumferential direction across the center sipe.

Abstract: Provided is a rubber composition having excellent breaking strength. The rubber composition contains an inverse vulcanizate having a glass transition temperature of 60° C. or lower.

Abstract: Provided is a rubber composition having excellent breaking strength. The rubber composition contains an inverse vulcanizate containing 10 mass % or more of carbon atoms and 30 mass % or more of sulfur atoms.

Abstract: Provided are a terminally modified diene-based polymer having excellent mechanical properties and also a method for producing the same. The terminally modified diene-based polymer is obtainable by allowing a diene-based polymer terminated with ketone or aldehyde groups to react with an aminophosphonic acid compound represented by general formula (1) or (2): wherein in formulas (1) and (2), R1 and R4 each represent a C1-10 alkanediyl group, R2 and R3 may be the same or different and each represent hydrogen, a C1-3 alkyl group, or a phenyl group, R5, R6, R8, and R9 may be the same or different and each represent hydrogen, a C1-3 alkyl group, or a phenyl group, and R7 represents hydrogen or a hydroxyl group.

Abstract: In a pneumatic tire, a center land comprises a plurality of center sipes, all of the center sipes are respectively contiguous with a first end and a second end in a tire axial direction of the center land, a first shoulder land comprises a plurality of first shoulder sipes, and all of the first shoulder sipes are contiguous with an outer end in the tire axial direction of the first shoulder land but are separated from an inner end in the tire axial direction of the first shoulder land.

Abstract: A pneumatic tire according to an embodiment includes a main groove extending in a tire circumferential direction on a tread, and a plurality of protrusions protruding from a bottom of the main groove and connected to walls on both sides in a tire axial direction of the main groove. Each of the protrusions is provided with a narrow groove extending in an extending direction of the main groove and dividing the protrusion into both sides in the tire axial direction, and the bottom of the narrow groove is at a higher position than the bottom of the main groove.

Abstract: A rubber strip manufacturing method that includes a step of extruding a rubber from an extrusion orifice of an extruder includes: a step of forming a long rubber member by extruding the rubber from the extrusion orifice that is circular; and a step of forming a rubber strip by passing the long rubber member through a gap between a pair of rotating rollers. The gap has a shape that is the widest in a central portion in a direction parallel to rotation axes of the rollers and that narrows as a distance from the central portion increases.

Abstract: A pneumatic tire includes: a first longitudinal groove and a second longitudinal groove extending in a tire circumferential direction; a first lateral groove extending obliquely with respect to a tire width direction and connected to the first longitudinal groove and the second longitudinal groove; a second lateral groove extending obliquely toward a side opposite to the first lateral groove with respect to a tire width direction and connected to the first longitudinal groove and the second longitudinal groove; and a trapezoidal block defined by the first longitudinal groove, the second longitudinal groove, the first lateral groove, and the second lateral groove. The block includes a first sipe and a second sipe extending obliquely toward opposite sides in the tire width direction.

Abstract: A method is disclosed for producing a tire rubber composition containing silica, a crosslinking compounding ingredient, and a rubber component containing 70 mass% to 100 mass% of a hydrogenated copolymer. The method includes hydrogenating an aromatic vinyl-conjugated diene copolymer, having a weight average molecular weight of 300,000 or more as measured by gel permeation chromatography, and having a hydrogenation rate of a conjugated diene moiety of 80 mol% or more. The method incudes: a first step of mixing 50 mass% to 95 mass% of 100 mass% of the hydrogenated copolymer with a total amount of the silica; a second step of mixing a rest of the hydrogenated copolymer with a mixture obtained in the first step; and a third step of mixing the crosslinking compounding ingredient with a mixture obtained in the second step.

Abstract: A pneumatic tire includes: a first and second main grooves extending in a tire circumferential direction; first and second inclined grooves extending obliquely toward the same side with respect to the tire circumferential direction and connected to the first and second main grooves; and a block defined by the first and second main grooves and the first and second inclined grooves. The block includes a sub groove having a first portion and a second portion, the first portion being open to an intermediate portion of the first inclined groove and extending in the tire circumferential direction, the second portion being inclined to a side opposite to the first inclined groove, extending from a terminal end of the first portion in a direction away from the first inclined groove, and being open to the first main groove.

Abstract: In a non-pneumatic tire, the plurality of connecting portions comprise first connecting portions extending in such fashion as to be directed from a first side in a tire width direction of an inner annular portion toward a second side in the tire width direction of an outer annular portion, and second connecting portions extending in such fashion as to be directed from the second side in the tire width direction of the inner annular portion toward the first side in the tire width direction of the outer annular portion, and at least one of the plurality of connecting portions comprises a main body portion having a width that is constant or that increases in tapered fashion by a constant ratio as viewed in the tire width direction, and an reinforcing portion that connects an end in a tire circumferential direction of the main body portion and the annular portion.

Abstract: A stitcher device presses a carcass ply to be pressure-bonded to a rubber member after that the carcass ply is wound around an outer periphery of a building drum movable along a drum guide path via a rubber member. The stitcher device includes an annular frame that is able to surround the outer periphery of the building drum by inserting the building drum thereinto, and a pressure-bonding device provided in the annular frame so as to be able to press the carcass ply from its outer periphery and pressure-bond the carcass ply to the rubber member. The annular frame is provided so as to be openable and closable by being divided into a plurality of parts in a peripheral direction.

Abstract: A rubber-steel cord composite in which a rubber composition and a steel cord are vulcanized and adhere to each other, wherein the rubber composition contains 1 to 10 parts by mass of a vulcanizing agent, 0.1 to 5 parts by mass of N,N-dibenzylbenzothiazole-2-sulfenamide, and 0.1 to 5 parts by mass of a bismaleimide compound, with respect to 100 parts by mass of diene rubber containing natural rubber.

Abstract: A rubber-steel cord composite according to an embodiment is formed by vulcanizing and bonding a rubber composition containing 1 to 10 parts by mass of sulfur, 0.1 to 5 parts by mass of N,N-dibenzylbenzothiazole-2-sulfenamide, and 0.1 to 5 parts by mass of either one or both of hexamethylene bis-thiosulfate disodium salt dihydrate and 1,6-bis(N,N-dibenzylthiocarbamoyldithio)hexane, with respect to 100 parts by mass of diene rubber containing natural rubber, and a steel cord. A pneumatic tire according to an embodiment includes the rubber-steel cord composite.

Abstract: A pneumatic tire includes a sidewall surface 10 having a profile surface formed in a curved surface shape and a decorative area 11 provided on the sidewall surface 10, in which a plurality of planes 19, 20 with a rhombus shape and a plurality of planes 21, 22 with a shape of part of a rhombus are tightly arranged in the decorative area 11 so that sides and vertices of the rhombuses correspond to one another, two planes 20, 21 and two planes 19, 22 in which perpendicular line directions are different are aligned in a tire radial direction, and vertices to be contact points between the two planes 20, 21 and between the two planes 19, 22 aligning in the tire radial direction are protruding vertices 23, 24 protruding in a normal line direction of the profile surface.

Abstract: A pneumatic tire includes a decorative area 11 provided on a sidewall surface 10, in which three kinds of planes 21, 22, and 23 with different inclinations with respect to a profile surface 20 are tightly arranged in the decorative area 11, two kinds of planes 21, 22, or 23 from the three kinds of planes 21, 22, and 23 are aligned in a first direction to make a pair, plural kinds of pairs with different combinations are aligned in a second direction, and boundaries 24 between each two planes 21, 22, or 23 aligned in the first direction are shifted in the first direction between the pairs adjacent in the second direction.

Abstract: A pneumatic tire has paired bead portions, paired sidewall portions, a tread portion, a plurality of lug grooves extending from a shoulder area of the tread portion to reach a buttress area of the sidewall portion, and a block defined by the plurality of lug grooves. The block includes a shoulder block provided in the shoulder area, and a buttress block provided in the buttress area. The buttress area is provided with an annular rib annularly extending along a tire circumferential direction. The lug grooves are comparted into an outside lug groove positioned in an outer side of the annular rib, and an inside lug groove positioned in an inner side of the annular rib. A widened portion is provided in at least part of the plurality of lug grooves so as to enlarge a width of the annular rib.

Abstract: A rubber composition contains silica in a diene rubber. A relaxation curve (free induction decay curve) obtained based on the unvulcanized sample is separated into two components, i.e., a component (S0) having a short relaxation time and a component (L0) having a long relaxation time. A relaxation curve (free induction decay curve) obtained based on the vulcanized sample is separated into two components, i.e., a component (S) having a short relaxation time and a component (L) having a long relaxation time. A weighted average value (T0) of a relaxation time of the component (S0) and a relaxation time of the component (L0) and a relaxation time (Ts) of the component (S) satisfy TS/T0 ? 0.26. A volume (Vs) of the component (S) and a volume (VL) of the component (L) satisfy VS/VL ? 0.26.