Patents by Inventor Tatsuo Fujimaki
Tatsuo Fujimaki has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 4824908Abstract: A butadiene-based rubber composition is disclosed, which contains not less than 20% by weight of a butadiene-based homopolymer or copolymer having a glass transition temperature (Tg) of not less than -105.degree. C., but less than -70.degree. C. and a Mooney viscosity (ML.sub.1+4, 100.degree. C.) of 10 to 150. The butadiene-based homopolymer or copolymer is obtained by polymerizing butadiene or random-copolymerizing butadiene with at least one kind of a monomer selected from the group consisting of another conjugated diene and an aromatic vinyl compound, and then reacting polymerization-active terminals thereof with an isocyanate compound and/or an isothiocyanate compound. The butadiene-based rubber composition has excellent resilience, fracture strength, and wear resistance as a vulcanizate as well as excellent processability as an unvulcanized rubber, and can be used as tire applications such as tire treads, undertreads, sidewalls, bead portions, etc.Type: GrantFiled: March 24, 1987Date of Patent: April 25, 1989Assignee: Japan Synthetic Rubber Co., Ltd.Inventors: Fumio Tsutsumi, Mitsuhiko Sakakibara, Noboru Shimada, Yoshihisa Fujinaga, Noboru Oshima, Tatsuro Hamada, Tatsuo Fujimaki
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Patent number: 4812525Abstract: A rubber composition is disclosed which contains, as a rubber component, 20-100% by weight of (A) polybutadiene polymerized by using a lithium initiator and 80 to 0% by weight of (B) another rubber component. The polybutadiene has the following physical properties (i)-(v):(i) The molecular weight distribution of Mw/Mn is 1.4 to 3.0 in which Mw and Mn are a weight average molecular weight and a number average molecular weight, respectively;(ii) A polymer component having the molecular weight being not more than 10.sup.5 when calculated as polystyrene is from 7 to 25%;(iii) The content of bound vinyl groups is from 10 to 25%;(iv) The content of tin atoms bonded to the polymer by tin-carbon bonds is not less than 50 ppm;(v) Mooney viscosity (ML.sub.1+4, 100.degree. C.) is from 20 to 70.Type: GrantFiled: July 16, 1987Date of Patent: March 14, 1989Assignees: Japan Synthetic Rubber Co., Ltd., Bridgestone CorporationInventors: Noboru Oshima, Yoshishige Chikatsu, Toshiaki Fukuhori, Tatsuro Hamada, Tatsuo Fujimaki
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Patent number: 4810746Abstract: Disclosed herein is a rubber composition for use in vibration insulating material, which comprises as rubber components 5-50 parts by weight of a copolymer consisting of 99.5-45% by weight of a conjugated diolefin, 0.5-30% by weight of an ethylenically unsaturated carboxylic acid and 0-40% by weight of another vinly monomer polymerizable therewith, and 50-95 parts by weight of at least one rubber selected from natural rubber and synthetic diene rubbers. This rubber composition is excellent in the breaking properties and vibration insulating properties with a small temperature dependence of hysteresis loss.Type: GrantFiled: September 10, 1987Date of Patent: March 7, 1989Assignees: Bridgestone Tire Company Limited, Japan Synthetic Rubber Company LimitedInventors: Fumio Tsutsumi, Makoto Kondo, Mitsuhiko Sakakibara, Masaru Oda, Masaki Ogawa, Akira Tsuchikura, Tatsuo Fujimaki
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Rubber composition for use in tire tread comprising a rubber component, carbon black and process oil
Patent number: 4791178Abstract: A rubber composition for use in tire is disclosed which contains at least 30% by weight, relative to the entire rubber component, of a conjugated diene-monovinyl aromatic hydrocarbon copolymer which uses an organic lithium compound as an initiator. A percentage of vinyl bonds in conjugated diene units in the copolymer molecules is from 50 to 95% and the content of the monovinyl aromatic hydrocarbon units is from 10 to 50% by weight. As physical properties of the vulcanized rubber of the rubber composition, aromatic hydrocarbon copolymer, 200% tensile modulus is from 5 to 50 kgf/cm.sup.2 and a temperture integrated value of a loss tangent, ##EQU1## is from 16 to 56. The tread rubber composition is suitable for a tread of high performance tires, and is excellent in fracture strength, thermal resistance, wear resistance, and road gripping property.Type: GrantFiled: October 27, 1987Date of Patent: December 13, 1988Assignee: Bridgestone CorporationInventors: Tatsuo Fujimaki, Noboru Oshima -
Patent number: 4782119Abstract: A rubber composition containing at least 20% by weight of a styrene-butadiene block copolymer consisting of a block (A) and a block (B) characterized in that: (i) the block (A) is a styrene-butadiene copolymer block having the content of styrene of 10-80% by weight and the average content of the vinyl bonds in the butadiene portion of 30-70% by weight; (ii) the block (B) is a polybutadiene block with the average content of the vinyl bonds in the butadiene portion being not more than 60% by weight (iii) the styrene-butadiene block copolymer contains at least 20% by weight of each of the block (A) and the block (B); (iv) the average content of the vinyl bonds in the butadiene portion of the block (A) is greater by at least 5% by weight than that of the block (B); (v) the glass transition temperature of the block (A) is higher by at least 30.degree. C.Type: GrantFiled: August 27, 1985Date of Patent: November 1, 1988Assignees: Japan Synthetic Rubber Co., Ltd., Bridgestone CorporationInventors: Fumio Tsutsumi, Akio Iakashima, Mitsuhiko Sakakibara, Noboru Oshima, Tatsuo Fujimaki, Yoshiyuki Morimoto
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Patent number: 4742124Abstract: YA rubber composition for use in tire having improved rolling resistance, wet skid resistance and processability is disclosed, which comprises at least 20% by weight of a conjugated diolefin-vinyl-substituted aromatic hydrocarbon random copolymer. This random copolymer is produced by copolymerization with a particular initiator and coupling with a particular coupling agent, and has a content of vinyl-substituted aromatic hydrocarbon of 3-60% by weight, a content of tin bonded to copolymer of not less than 400 ppm and a Mooney viscosity (ML.sub.1+4.sup.100.degree.C.) of 20-200.Type: GrantFiled: July 6, 1987Date of Patent: May 3, 1988Assignees: Japan Synthetic Rubber Co., Ltd., Bridgestone CorporationInventors: Fumio Tsutsumi, Mitsuhiko Sakakibara, Yoshihisa Fujinaga, Noboru Oshima, Tatsuo Fujimaki
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Patent number: 4742117Abstract: A rubber composition containing not less than 20% of a conjugated diene based polymer or copolymer. The polymer or copolymer is obtained by polymerizing a conjugated diene or copolymerizing the conjugated diene with at least one kind of other conjugated diene and an aromatic vinyl compound with use of a lithium initiator, and then reacting an isocyanate compound with active terminals of the thus obtained polymer or copolymer. The conjugated diene is butadiene or isoprene, while other conjugated diene is selected from pentadiene, 2,3-dimethylbutadiene as well as isoprene and butadiene, and an aromatic vinyl compound may be styrene, vinyltoluene, .alpha.-methylstyrene, etc. The rubber composition is applicable as tread portion, carcass, side wall portion of tires, vibration resistant rubber, window frame, hose, and various industrial articles.Type: GrantFiled: April 17, 1987Date of Patent: May 3, 1988Assignees: Japan Synthetic Rubber Co., Ltd., Bridgestone CorporationInventors: Fumio Tsutsumi, Mitsuhiko Sakakibara, Noboru Shimada, Yoshihisa Fujinaga, Noboru Oshima, Tatsuro Hamada, Tatsuo Fujimaki
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Patent number: 4721753Abstract: A diene polymer composition having improved fracture properties and a small change in the shape of extruded product is disclosed, which comprises at least 5% by weight of a copolymer composed of at least one conjugated diene (component A) having the following general formula: ##STR1## wherein R.sub.1 and R.sub.2 are a hydrogen atom or a methyl group, and 2,3-dimethylbutadiene (component B), said copolymer having a content of cis-1,4-bond of not less than 80%.Type: GrantFiled: April 8, 1986Date of Patent: January 26, 1988Assignees: Bridgestone Corporation, Japan Synthetic Rubber Co., Ltd.Inventors: Mitsuhiko Sakakibara, Kaoru Nakako, Tatsuo Fujimaki
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Patent number: 4603722Abstract: A branched styrene-butadiene copolymer and a pneumatic tire using the same as a tread base rubber are disclosed. This copolymer is produced by coupling an active styrene-butadiene copolymer anion, which is obtained by polymerizing styrene and butadiene in a hydrocarbon solvent in the presence of ether or a tertiary amine and an initiator of an organolithium compound, with a tin halide compound. In the copolymer, the ratio of branched copolymer connected with tin-butadienyl bond is at least 20% by weight, and the content of bound styrene is not less than 3% by weight but less than 25% by weight, and the content of vinyl bond in butadiene portion is not less than 30% but less than 50%.Type: GrantFiled: September 28, 1984Date of Patent: August 5, 1986Assignees: Bridgestone Tire Company, Japan Synthetic Rubber Co., Ltd.Inventors: Noboru Oshima, Isamu Shimizu, Yoshito Yoshimura, Tatsuo Fujimaki, Seisuke Tomita
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Patent number: 4575534Abstract: Disclosed herein is a rubber composition comprising at least 20% by weight of styrene-butadiene copolymer based on the total weight of the rubber content. The styrene-butadiene copolymer is obtained by randomly copolymerizing styrene with 1,3-butadiene in a hydrocarbon solvent in the presence of an organolithium compound as an initiator and then subjecting to a coupling reaction with a polyfunctional coupling agent, and contains 30-70% by weight of branched polymers therein, and has the following properties:(a) a content of bound styrene in the copolymer 3-15% by weight;(b) a content of vinyl bonds contained in the butadiene units is 15-30% by weight;(c) a Mooney viscosity (ML.sub.1+4.sup.100.degree. C.) is 15-50; and(d) a molecular weight distribution of the copolymer is bimodal at a ratio Mw/Mn of 1.4-2.2 in which Mw is a weight-average molecular weight and Mn is a number-average molecular weight.Type: GrantFiled: April 6, 1984Date of Patent: March 11, 1986Assignees: Bridgestone Tire Company Limited, Japan Synthetic Rubber Company LimitedInventors: Noboru Oshima, Isamu Shimizu, Mikio Takeuchi, Tatsuo Fujimaki, Shinsuke Yamaguchi
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Patent number: 4526934Abstract: A branched styrene-butadiene copolymer and a pneumatic tire using the same as a tread base rubber are disclosed. This copolymer is produced by coupling an active styrene-butadiene copolymer anion, which is obtained by polymerizing styrene and butadiene in a hydrocarbon solvent in the presence of ether or a tertiary amine and an initiator of an organolithium compound, with a tin halide compound. In the copolymer, the ratio of branched copolymer connected with tin-butadienyl bond is at least 20% by weight, and the content of bound styrene is not less than 3% by weight but less than 25% by weight, and the content of vinyl bond in butadiene portion is not less than 30% but less than 50%.Type: GrantFiled: March 8, 1983Date of Patent: July 2, 1985Assignee: Bridgestone Tire Company LimitedInventors: Noboru Oshima, Isamu Shimizu, Yoshito Yoshimura, Tatsuo Fujimaki, Seisuke Tomita
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Patent number: 4519431Abstract: A styrene-butadiene copolymer having a high styrene content is disclosed, which is obtained by polymerizing styrene and butadiene in a hydrocarbon solvent in the presence of an organolithium compound and, if necessary, a Lewis base and then coupling with a tin halide compound. This copolymer contains in its main chain at least 30 wt % of polymer having a tin-carbon bond and has a bound styrene content of more than 25 wt % but not more than 60 wt % and a content of vinyl bond in butadiene portion of not less than 30% but less than 50%.Type: GrantFiled: July 19, 1984Date of Patent: May 28, 1985Assignees: Bridgestone Tire Company Limited, Japan Synthetic Rubber Co., Ltd.Inventors: Yoshito Yoshimura, Noboru Oshima, Isamu Shimizu, Shinsuke Yamaguchi, Tatsuo Fujimaki, Tomoharu Yamada, Seisuke Tomita
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Patent number: 4485205Abstract: Rubber compositions for tires having low rolling resistance and excellent running stability consist mainly of a rubber blend consisting of 10-90% by weight of a high vinyl amorphous butadiene-styrene copolymeric rubber obtained by copolymerizing styrene with 1,3-butadiene and containing 3-30% by weight of bonded styrene and not less than 60% by weight of 1,2-bond in butadiene unit, and 90-10% by weight of a dienic rubber having a glass transition temperature of lower than -60.degree. C.Type: GrantFiled: November 29, 1982Date of Patent: November 27, 1984Inventors: Tatsuo Fujimaki, Tomoharu Yamada, Keiko Katayama, Seisuke Tomita
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Patent number: 4481995Abstract: A pneumatic radial tire having sidewalls, the rubber composition of said sidewalls comprising, based on 100 parts by weight of rubber, 20 to 90 parts by weight of butadienepiperylene copolymer and 80 to 10 parts by weight of at least one rubbery diene polymer selected from the group consisting of natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, butadiene-styrene copolymer rubber, ethylenepropylene-diene ternary copolymer rubber and acrylonitrile-butadiene copolymer rubber.Type: GrantFiled: September 14, 1982Date of Patent: November 13, 1984Assignee: Bridgestone Tire Co., Ltd.Inventors: Masaki Ogawa, Yasushi Hirata, Tatsuo Fujimaki, Tomoharu Yamada, Seisuke Tomita
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Patent number: 4463133Abstract: A rubber composition suitable for use in tire tread is disclosed, which contains at least 20 parts by weight of a block copolymer per 100 parts by weight of total rubber content. This block copolymer comprises (A) a polymer segment obtained by starting from conjugated diolefin and monovinyl aromatic hydrocarbon and having a content of monovinyl aromatic hydrocarbon bond of not more than 10% by weight and (B) a copolymer segment obtained by copolymerization of conjugated diolefin and monovinyl aromatic hydrocarbon and having a content of monovinyl aromatic hydrocarbon bond of 15-50% by weight.Type: GrantFiled: June 2, 1982Date of Patent: July 31, 1984Assignees: Bridgestone Tire Company Limited, Japan Synthetic Rubber Co., Ltd.Inventors: Yasumasa Takeuchi, Mitsuhiko Sakakibara, Fumio Tsutsumi, Akio Takashima, Tatsuo Fujimaki, Shinsuke Yamaguchi, Seisuke Tomita
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Patent number: 4396743Abstract: A rubber composition adapted to be used as a tread rubber is disclosed. The rubber composition has remarkably improved resistance against heat generation, breakage resistance, wear resistance, wet skid resistance and low-temperature brittleness, and consists mainly of a rubber blend consisting of 20-95 parts by weight of a styrene-butadiene block copolymer having a specifically limited structure and 80-5 parts by weight of a diene rubber.Type: GrantFiled: December 23, 1981Date of Patent: August 2, 1983Assignee: Bridgestone Tire Company LimitedInventors: Tatsuo Fujimaki, Tomoharu Yamada, Seisuke Tomita
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Patent number: 4383085Abstract: A rubber composition for tire having low rolling resistance and high wet skid resistance, breakage strength and wear resistance consists mainly of a rubber component containing at least 20 parts by weight of a high vinyl butadiene-styrene copolymer rubber obtained by copolymerizing randomly styrene with 1,3-butadiene, and containing 3-30% by weight of bonded styrene and 60-95% by weight of 1,2-bond in butadiene unit, and further containing metal-butadienyl bonds in its main chain in a weight fraction of at least 20% by weight.Type: GrantFiled: September 16, 1981Date of Patent: May 10, 1983Assignee: Bridgestone Tire Co., Ltd.Inventors: Tatsuo Fujimaki, Shinsuke Yamaguchi, Tomoharu Yamada, Seisuke Tomita