Sumitomo Rubber Industries Limited

Shuichiro Ono

Yuka Yokoyama

Ryuichi Tokimune

Subaru Toya

Kenichi Uesaka

Katsumi Terakawa

Tetsuya Kunisawa

Hiroshi Ito

Tatsuhiro Tanaka

Takahiro Kawachi

Masako Nakatani

Fumiya Kato

Keiichi Nakadera

Tetsuya Maekawa

Natsuki Maekawa

Ayuko Yamada

Seiji Hatano

Satomi Yamauchi

Masataka Hiro

Daiki Mukouguchi

The present invention aims to provide tire rubber composition with significantly improved overall performance in terms of wet grip performance and fuel economy, and pneumatic tires including the rubber compositions. The tire rubber compositions of the present invention have a tan δ versus temperature curve whose peak tan δ and half width satisfy the following relationship (1):Peak tan δ/Half width≥0.025  (1).

Tire rubber composition and pneumatic tire

An object of the invention is to provide a tire having little change in riding comfort performance and wet performance before and after wear of the tread part and in which riding comfort performance and wet performance as when the tire is newly used are maintained. The fire comprises a tread being composed of a rubber layer in which there is little change in hardness after thermal deterioration and having a groove shape such that a sea ratio after wear with respect to a sea ratio as when the tire is newly used is within a predetermined range.

Tire

A pneumatic tireincludes a carcassextending between bead cores of bead portions via a tread portionand sidewall portions, and a belt layerarranged on an outer side in a tire radial direction of the carcassand inside the tread portion. The pneumatic tirehas a noise damperarranged on an inner cavity surface of the tread portion. Glass transition temperature of the noise damperis in a range of from −55 degrees Celsius to −45 degrees Celsius.

Pneumatic tire

A studless tire having a tread composed of a rubber composition for a tread comprising 1 to 20 parts by mass of a farnesene resin and 1 to 20 parts by mass of a terpene resin based on 100 parts by mass of a rubber component.

Studless tire

The present invention provides a pneumatic tire and a rubber composition for tires, which have improved durability at high temperatures and during high-speed running while ensuring good ice performance. The present invention relates to a pneumatic tire, including a tread, the tread including blocks having an average ripe density of 1.0 cm/cmor higher and an average height of 0.6 to 2.0 cm, the blocks containing a rubber composition having a tan &#x3b4; at 100&#xb0; C. of 0.179 or less as determined at an initial strain of 10%, a dynamic strain of 2%, and a frequency of 10 Hz, and has a ratio of the modulus at 100&#xb0; C. to the modulus at room temperature of 69% or greater as determined in accordance with JIS K6251:2010.

Pneumatic tire, and rubber composition for tire

Provided are a cap tread rubber composition for cold weather tires enabling a balanced improvement in fuel economy, abrasion resistance, performance on ice/snow, and high-speed performance on snow-/ice-free cold roads, and a cold weather tire formed from the same. The rubber composition contains: a rubber component including BR, SBR, and NR and/or IR; and a filler, the composition having a combined amount of NR, IR, and BR of 80% by mass or more, an amount of BR of 30% by mass or more, and an amount of SBR of 0.3-10% by mass, each per 100% by mass of the rubber component, the filler including 60% by mass or more of silica per 100% by mass of the filler, the composition containing, per 100 parts by mass of the rubber component, 50 parts by mass or more of a fine particle silica having a NSA of 190 m/g or more.

Cap tread rubber composition for cold weather tires

The present invention provides a cold weather tire achieving a balanced improvement in conductivity, fuel economy, performance on ice and snow, high speed performance (handling stability, grip performance) on snow- and ice-free cold roads, and road noise performance. Provided is a pneumatic tire including: a two-layer tread including a base tread and a cap tread, the base tread being formed of a rubber composition for base treads containing: predetermined amounts of a rubber component including natural rubber and/or polyisoprene rubber, and a filler including silica and carbon black, the cap tread being formed of a rubber composition for cap treads containing a predetermined amount of silica, the cap tread having cells and/or voids.

An object of the present invention is to provide a rubber composition which can further improve abrasion resistance without deterioration in energy efficiency, and a pneumatic tire using the rubber composition. The rubber composition comprises a polymer mixture obtained by modifying a polymer composed of at least one of a conjugated diene compound and an aromatic vinyl compound with a compound having at least one of an ester group and a carboxyl group; at least one of triamines; and silica, the polymer mixture having a weight-average molecular weight of 1.0&#xd7;10to 1.0&#xd7;10, and the triamines being a compound represented by the following formula (I): wherein each of R, R, R, Rand Rindependently represents a hydrogen atom or an alkyl group, and each of ALKand ALKindependently represents an alkylene group.

Rubber composition and pneumatic tire

An object of the present invention is to provide a rubber composition which can further improve abrasion resistance without deterioration in energy efficiency, and a pneumatic tire using the rubber composition. The rubber composition comprises a polymer mixture obtained by modifying a polymer composed of at least one of a conjugated diene compound and an aromatic vinyl compound with a compound having at least one of an ester group and a carboxyl group; at least one of tetraamines; and silica, the polymer mixture having a weight-average molecular weight of 1.0&#xd7;10to 1.0&#xd7;10, and the tetraamines being a compound represented by the following formula (I): wherein each of R, R, R, R, R, R, Rand Rindependently represents a hydrogen atom or an alkyl group, and ALK represents a tetravalent aliphatic hydrocarbon group.

Provided are: a rubber composition achieving balanced improvement in fuel economy, abrasion resistance, and processability, and a pneumatic tire including the composition. The rubber composition includes: a conjugated diene polymer; silica; and a silane coupling agent, the polymer being obtained by polymerizing a monomer component including a conjugated diene compound and a silicon-containing vinyl compound in the presence of a polymerization initiator of formula (I): to produce a copolymer, and reacting a compound containing nitrogen and/or silicon atoms with an active terminal of the copolymer, wherein the rubber composition contains the conjugated diene polymer in an amount of 5-45% by mass per 100% by mass of a rubber component, the silica in an amount of 5 to 100 parts by mass per 100 parts by mass of the rubber component, and the coupling agent in an amount of 2-12 parts by mass per 100 parts by mass of the silica.

Provided are a rubber composition capable of achieving a balanced improvement in fuel economy, tensile strength at break, and processability, and a pneumatic tire including the rubber composition. The invention relates to a rubber composition including a conjugated diene polymer and silica, the conjugated diene polymer being obtained by polymerizing a monomer component including a conjugated diene compound and a silicon-containing vinyl compound in the presence of a polymerization initiator represented by the following formula (I): to produce a copolymer, and reacting a compound containing a nitrogen atom and/or a silicon atom with an active terminal of the copolymer, wherein the rubber composition includes the conjugated diene polymer in an amount of not less than 10% by mass per 100% by mass of a rubber component of the rubber composition, and the silica in an amount of 10-70 parts by mass per 100 parts by mass of the rubber component.

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Kobe, Japan

Shuichiro Ono