Patents by Inventor Tasuku Saito

Tasuku Saito 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).

  • Patent number: 5130042
    Abstract: Electrorheological fluids display swift and reversible increase in apparent viscosity under application of an electrical potential difference to the fluid, and are composed generally of electrical insulating oily medium and dielectric fine-particles dispersed therein.It is an object of the present invention to provide an electrorheological fluid capable of exhibiting enhanced electrorheological effect with smaller electric power consumption.Electrorheological fluid according to the present invention comprises particulates having a specific gravity of not smaller than 1.2 and water content of not larger than 4 wt. % dispersed in an electrical insulating oily medium havingf P.dbd.N bonds in the molecule.
    Type: Grant
    Filed: October 25, 1990
    Date of Patent: July 14, 1992
    Assignee: Bridgestone Corporation
    Inventors: Yasuo Kurachi, Mitsuya Tanaka, Yuichi Ishino, Tasuku Saito
  • Patent number: 5106521
    Abstract: Electrorheological fluids display swift and reversible increase in apparent viscosity under application of an electrical potential difference to the fluid, and are composed generally of electrical insulating oily medium and dielectric fine-particles dispersed therein.At the initial stage of development, electrorheological fluids are prepared by dispersing water-carrying hydrophilic particulates in an electrical insulating oily medium. However, there are such defects as a restriction on usable temperatures so as to avoid evaporation or freezing of the water, an extreme increase in the electric current flow as the temperature raises, inferior stability caused by transfer of water etc.It is an object of the persent invention is to provide nonaqueous type electrorheological fluids having improved electrorheological property.The electrorheological fluid of the present invention is a nonaqueous type electrorheological fluid which comprises organic or inorganic particulates containing not more than 1 wt.
    Type: Grant
    Filed: October 9, 1990
    Date of Patent: April 21, 1992
    Assignee: Bridgestone Corporation
    Inventors: Yasuo Kurachi, Osaki Toshiyuki, Mitsuya Tanaka, Yuichi Ishino, Tasuku Saito
  • Patent number: 5087382
    Abstract: The electroviscous fluid is a suspension composed of a finely divided dielectric solid dispersed in an electrically nonconductive oil. The viscosity of the fluid increases swiftly and reversibly under an influence of electric field applied thereto and the fluid turns to a state of plastic or solid when the influence is sufficiently strong.The electroviscous fluid of the present invention comprises 1-60% by weight of a dispersed phase of carbonaceous particulates having average particle size of 0.01-100 micrometer, and 99-40% by weight of a continuous liquid phase of an electric insulating oil having a viscosity of 0.65-500 centistokes at room temperature.The electroviscous fluid exhibits an excellent electroviscous effect even at a high temperature with a low electric power consumption together with maintaining the improved electroviscous effect for a long period of time.
    Type: Grant
    Filed: August 29, 1989
    Date of Patent: February 11, 1992
    Assignee: Bridgestone Corporation
    Inventors: Yuichi Ishino, Toshiyuki Osaki, Shigeki Endo, Seisuke Tomita, Takayuki Maruyama, Yoshiki Fukuyama, Tasuku Saito
  • Patent number: 5075023
    Abstract: The electroviscous fluid is a suspension composed of a finely divided dielectric solid dispersed in an electrically nonconductive oil. Viscosity of the fluid increases swiftly and reversibly under an influence of electric field applied thereto and the fluid turns to a state of plastic or solid when the influence is sufficiently strong.The electroviscous fluid of the present invention comprises(A) 1-60% by weight of a dispersed phase composed of hygroscopic inorganic particles having an average particle size of 0.01-20 micrometer and regulated to a water content of 0.1-10% by weight and adsorbing a high boiling point liquid polar compound, and(B) 99-40% by weight of a liquid phase of an electric insulating oil having a viscosity 0.65-500 centistokes at room temperature.The electroviscous fluid exhibits an excellent electroviscous effect for a long period of time with a low electric power consumption together with a quick response at the application and cancellation of an electric potential difference.
    Type: Grant
    Filed: November 30, 1989
    Date of Patent: December 24, 1991
    Assignee: Bridgestone Corporation
    Inventors: Yoshiki Fukuyama, Yuichi Ishino, Toshiyuki Osaki, Takayuki Maruyama, Tasuku Saito
  • Patent number: 4919434
    Abstract: Disclosed herein is a two-piece type solid golf ball formed by enclosing a solid core with a thermoplastic resin cover. It provides a long overall distance, improved controlability, extended durability, and good shot feeling. The solid core contains polybutadiene having more than 40% of cis-1,4 bonds and an unsaturated carboxylic acid and/or a metal salt thereof to crosslink the polybutadiene and deforms 1.5 to 3.5 mm under a constant load of 100 kg. The cover is 0.4 to 2.2 mm thick and consists of a 0.1 to 2 mm thick inner layer and a 0.1 to 1.5 mm thick outer layer enclosing the inner layer, both made of thermoplastic resins, said inner layer generating a stress of 20 to 100 kg/cm.sup.2 at 10% elongation and having a resilience higher than 40%, and said outer layer having a flexural modulus of 2000 to 5000 kg/cm.sup.2 and a resilience higher than 35%.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: April 24, 1990
    Assignee: Bridgestone Corporation
    Inventor: Tasuku Saito
  • Patent number: 4858924
    Abstract: Solid golf balls comprising a solid core and a cover which exhibit improved flying performance, controllability, repulsion, fatigue resistance, and hitting feel. The solid core is formed from a composition comprising a polybutadiene containing at least 40% of cis-1,4-bond and an unsaturated carboxylic acid and/or a metal salt thereof for causing crosslinking of the polybutadiene and having a deformation of 1.5 to 3.5 mm under a constant load of 100 kg, and the difference in hardness between the center and the periphery of said solid core is less than 10%; and the cover is formed from a thermoplastic resin composition comprising 97 to 65% by weight of an ionomer resin and 3 to 35% by weight of a flexible resin selected from the group consisting of polyester elastomers, polyamide propylene-butadiene copolymers, 1,2 polybutadienes, polybutiene-1, and sytrene-butadiene block copolymers and mixtures thereof, and having a resilience of at least 35%, and having a flexural modulus of 1,500 to 4,500 kg/cm.sup.
    Type: Grant
    Filed: March 11, 1988
    Date of Patent: August 22, 1989
    Assignee: Bridgestone Corporation
    Inventors: Tasuku Saito, Shinichi Kakiuchi
  • Patent number: 4683257
    Abstract: Solid golf balls are formed from a molding composition comprising (1) a polybutadiene blend of (A) a polybutadiene synthesized using a nickel and/or cobalt base catalyst and having a Mooney viscosity of 70 to 100 with (B) less than 50 parts by weight of a polybutadiene synthesized using a lanthanide rare earth element base catalyst and having a Mooney viscosity of 30 to 90 or (C) 20 to 80 parts by weight of a polybutadiene synthesized using a nickel and/or cobalt base catalyst and having a Mooney viscosity of 20 to 50, the polybutadienes containing at least 40% of cis-1,4 bond, (2) a crosslinking agent such as acrylic and methacrylic acid, (3) an inorganic filler, and (4) an organic peroxide.
    Type: Grant
    Filed: June 11, 1986
    Date of Patent: July 28, 1987
    Assignee: Bridgestone Corporation
    Inventors: Shinichi Kakiuchi, Tasuku Saito, Seisuke Tomita
  • Patent number: 4398000
    Abstract: A solid type golf ball comprising a central core and an outer cover for the core and having an excellent flight performance and durability and acceptable "click" characteristics is presented. The main component of the outer cover of this golf ball is a polyetherester block copolymer containing the following X, Y and Z units:X: Butylene terephthalate unitY: Ester unit other than butylene terephthalateZ: Polyetherester unit derived from a dicarboxylic acid component containing terephthalic acid and poly(alkylene oxide) glycol having a number average molecular weight of 400 through 3000, wherein the X, Y and Z units are present in the following amounts:30% by weight .ltoreq.X.ltoreq.80% by weight0% by weight .ltoreq.Y.ltoreq.50% by weight20% by weight .ltoreq.Z.ltoreq.70% by weight.
    Type: Grant
    Filed: August 7, 1981
    Date of Patent: August 9, 1983
    Assignees: Bridgestone Tire Co., Ltd., Toray Industries, Inc.
    Inventors: Nobuyuki Kataoka, Tasuku Saito, Tsutomu Matsunaga, Chiaki Tanaka, Yoko Furuta, Nagayoshi Naito
  • Patent number: 4353557
    Abstract: A golf ball having a large carry having a core, a rubber thread layer and a cover layer, in which the rubber thread is composed of a rubber composition consisting essentially of 100 parts by weight of natural rubber and/or cis-1,4-polyisoprene and 2-20 parts by weight of carbon black.
    Type: Grant
    Filed: March 3, 1980
    Date of Patent: October 12, 1982
    Assignee: Bridgestone Tire Company, Limited
    Inventors: Ryota Kajita, Tasuku Saito, Tsutomu Matsunaga, Sakae Inoue, Masayuki Ohtake
  • Patent number: 4337947
    Abstract: An improved golf ball having a thread-wound central core and an outer cover is provided. The outer cover is composed of a composition comprising (a) at least one ionomer which is a copolymer of at least one .alpha.-olefin and at least one .alpha.,.beta.-unsaturated carboxylic acid to which copolymer at least one metal ion selected from the group consisting of monovalent, divalent and trivalent metal ions is added and (b) at least one polyester elastomer, the content, in said composition, of said polyester elastomer being 50% by weight or less. This golf ball has excellent cutting resistance, "click" characteristics and impact resilience.
    Type: Grant
    Filed: November 21, 1980
    Date of Patent: July 6, 1982
    Assignees: Bridgestone Tire Co., Ltd., Toray Industries, Inc.
    Inventors: Tasuku Saito, Tutomu Noma, Tsutomu Matsunaga, Chiaki Tanaka, Yoko Furuta, Nagayoshi Naito
  • Patent number: 4337946
    Abstract: A golf ball having an intermediate layer of thermoplastic resin between a thread-wound central core and an outer polyester elastomer layer. The thermoplastic resin has a substantial melt flow initiation temperature of 160.degree. C. or less, the substantial melt flow initiation temperature being the minimum temperature at which the melt index under a load of 4350 g. becomes 1 g/10 mins or more, and has a high adhesion property to the polyester elastomer cover. It is preferable that the thermoplastic resin have a resilience of 30% or more and that the intermediate layer of thermoplastic resin be within the range of 0.1 to 1.0 mm. This golf ball has excellent cutting resistance, "click" characteristics and impact resilience.
    Type: Grant
    Filed: November 6, 1980
    Date of Patent: July 6, 1982
    Assignees: Toray Industries, Inc., Bridgestone Tire Company Limited
    Inventors: Tasuku Saito, Tutomu Noma, Tsutomu Matsunaga, Nagayoshi Naito, Chiaki Tanaka, Motoki Hiratsuka
  • Patent number: 4295652
    Abstract: A golf ball having a thread-wound core and a cover formed of a block copolyetherester comprising (A) a terephthalic acid unit, (B) a 1,4-butanediol unit, (C) a unit of a dicarboxylic acid, other than terephthalic acid, or a short-chain diol, other than 1,4-butanediol, having a number-average molecular weight of not more than 300 and (D) a poly(alkylene oxide)glycol unit having a number-average molecular weight of from 500 to 3000. Said golf ball exhibits excellent impact resilience and also exhibits good cutting resistance and "click".
    Type: Grant
    Filed: February 8, 1980
    Date of Patent: October 20, 1981
    Assignees: Bridgestone Tire Co., Ltd., Toray Industries, Inc.
    Inventors: Tasuku Saito, Tutomu Noma, Tsutomu Matsunaga, Nagayoshi Naito, Chiaki Tanaka, Motoki Hiratsuka