Sumitomo Rubber Industries

Provided are a rubber composition and a tire that have excellent overall performance in terms of fuel economy, abrasion resistance, and wet grip performance. The rubber composition contains a silane coupling agent, the silane coupling agent including an organosilicon compound containing at least one of a silanol group or an alkoxysilyl group, the silane coupling agent having a ratio (percentage of a dimer/total percentage of a monomer and a dimer) of a percentage of a dimer of the organosilicon compound relative to a total percentage of a monomer and the dimer of the organosilicon compound of 0.40 or lower.

A golf ball 2 has a plurality of dimples 10 on a surface thereof. An occupation ratio X of the dimples is 70% or more. A value Z of the golf ball 2, calculated by the following mathematical formula, is less than 0.0. Z=−535.36*Db+146.46*Lb−238.52*Da+225.22*La+111.21Db: drag coefficient under a first conditionLb: lift coefficient under the first conditionDa: drag coefficient under a second conditionLa: lift coefficient under the second conditionFirst conditionReynolds number: 1.20 * 10⁵Ratio (rω/V): 0.131Second conditionReynolds number: 0.83 * 10⁵Ratio (rω/V): 0.179The ratio (rω/V) is calculated by dividing a product of a radius r (m) and a backspin rate ω (rad/s) of the golf ball 2 by a speed V (m/s) of the golf ball 2.

A pneumatic tire (1) having a protruding portion (25) including a top portion (26) and a rim fit profile (27). In a tire meridian section of the pneumatic tire (1) in a standard state, a parameter X relating to rim chafing resistance performance, defined by X = (A+10) × B × Hs × E/10<5>, is 34 or more, where A: the shortest distance from the top portion (26) to a rim flange (16); B: a distance from the top portion (26) to a tire radial direction line (RL) defining a rim width; Hs: a rubber hardness of a bead apex rubber (8); E: a modulus of a carcass ply (6A) calculated by E = (F/G) × H; G: an intermediate elongation (%) of a carcass cord under a constant load F; F: the constant load (N) applied when obtaining the intermediate elongation G; and H: ends of the carcass cords.

A pneumatic tire 1 includes a tread portion 2, and a sound damper 11 made of a porous material and fixed to a tire inner cavity surface 15s of the tread portion 2. The sound damper 11 extends in a tire circumferential direction along a tire equator C. In a 70% load-applied state where the pneumatic tire 1 is fitted on a standardized rim at a standardized internal pressure, 70% of a standardized load is applied to the pneumatic tire 1, and the pneumatic tire 1 is brought into contact with a flat surface at a camber angle of 0 degrees, a ground-contact surface 14 of the tread portion 2 has a ratio L/Lm of a maximum ground-contact length L in the tire circumferential direction to a ground-contact length Lm, in the tire circumferential direction, within a range centered on the tire equator C and equal to or less than 70% of a maximum ground-contact width W in a tire axial direction, and the ratio L/Lm satisfies the following formula (1): 1.00 < L / Lm < 1.10 <img class="EMIRef" id="6d888a8c-dd71-42ae-b6cf-483644f019c2-ia01" />

Provided is a tire 1 that can improve wet performance and heat dissipation property from an early stage of wear to a late stage of wear while maintaining rolling resistance performance and wear resistance performance. The tire 1 includes a tread 10 having a tread surface TRS. The tread 10 has a plurality of circumferential grooves 300. The plurality of circumferential grooves 300 divide the tread 10 into a plurality of land portions 200, and have a pair of circumferential main grooves 330 and at least one circumferential narrow groove 320. The circumferential narrow groove 320 has a narrow width portion 321 and an enlarged width portion 322. A groove width NIW of the narrow width portion 321 has a width at which, when the tire 1 comes into contact with the road surface, side walls (321a, 321b) of the narrow width portion 321 come into contact with each other. At least one of the land portions 200, which is adjacent to the circumferential narrow groove 320, has a plurality of pinholes 100. A depth PHD of the pinhole 100 is shallower than a depth CMD of the circumferential main groove 330. The pinhole 100 has a shape tapering toward the inner side in the tire radial direction. The relationship between a width L1 of the land portion 200 having the pinhole 100 and a distance L2 from the circumferential narrow groove 320 to the pinhole 100 satisfies the following Formula (1): 0.3 ≤ L 2 / L 1 ≤ 0.7 <img class="EMIRef" id="073c77b3-bed1-4340-86eb-7e24600469af-ia01" />

A tire 2 includes a tread 4 and a reinforcing layer 14. The tread 4 includes a rubber composition containing a rubber component and a filler. The rubber component contains SBR and isoprene-based rubber. The filler contains carbon black and silica. The reinforcing layer 14 includes a reference full band BF. An amount CNR of the isoprene-based rubber, an amount BCB of the carbon black, and a cord count Ej of the reference full band BF satisfy the following relational expression. CNR + BCB × Ej ≥ 900 <img class="EMIRef" id="afca1508-8445-4f7d-9fb4-343fe5c0bf85-ia01" />

A tire 2 includes a tread 4 and a reinforcing layer 14. The tread 4 includes a rubber composition containing a rubber component and a filler. The rubber component contains SBR and isoprene-based rubber. The filler contains carbon black and silica. The reinforcing layer 14 includes a reference full band BF. An amount CNR of the isoprene-based rubber, an amount BCB of the carbon black, and a ratio (Wj/Wt) of an axial width Wj of the reference full band BF to an axial width Wt of the tread 4 satisfy the following relational expression. CNR + BCB × Wj / Wt ≥ 27.0 <img class="EMIRef" id="4518fd5a-c5c6-4614-b11c-ce11b246765a-ia01" />

A tire 2 includes a tread 4 and a reinforcing layer 14. The tread 4 includes a rubber composition containing a rubber component and a filler. The rubber component contains SBR and isoprene-based rubber. The filler contains carbon black and silica. The reinforcing layer 14 includes a reference belt ply BP and a reference full band BF. An amount CNR of the isoprene-based rubber, an amount BCB of the carbon black, an inclination angle Ab of a belt cord 46 of the reference belt ply BP, and an inclination angle Aj of a band cord 52 of the reference full band BF satisfy the following relational expression. CNR+BCB/Ab+Aj≥1.80

A pneumatic tire 1 includes at least one electronic component 21. The electronic component 21 is covered with a cover rubber having an electrical resistivity of 1.0×10<10> Ω·cm or more. When a height Ha of a bead apex rubber 8 in a tire radial direction from an outer surface 5a of a bead core 5 is less than 25 mm, the electronic component 21 is placed in a region between 5 mm or more and 25 mm or less from the outer surface 5a of the bead core 5 to an outer side in the tire radial direction. When the height Ha of the bead apex rubber 8 is 25 mm or more, the electronic component 21 is placed in a region A2 between 5 mm or more from the outer surface 5a of the bead core 5 to the outer side in the tire radial direction and an outer end 8e in the tire radial direction of the bead apex rubber 8 or therebelow.

Provided is a tire with excellent wet grip performance. The tire includes a tread including a rubber composition, the tread having a circumferential groove, the rubber composition containing a rubber component including a rubber having an amino group; a filler including silica; and an ionic bonding coupling agent, the tire satisfying the relationship: D × S > 300 wherein D represents a maximum depth (mm) of the circumferential groove, and S represents an amount (parts by mass) of the silica per 100 parts by mass of the rubber component.