Patents by Inventor Godo Sakamoto

Godo Sakamoto 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: 7811673
    Abstract: To provide a novel high strength polyethylene multifilament which consists of a plurality of filaments having high strengths and uniform internal structures, and showing a narrow variation in the strengths of the monofilaments, and which has been difficult to be provided by the conventional gel spinning method. A high strength polyethylene multifilament consisting of a plurality of filaments which are characterized in that the crystal size of monoclinic crystal is 9 nm or less; the stress Raman shift factor is ?5.0 cm?1/(cN/dTex) or more; the average strength is 20 CN/dTex or higher; the knot strength retention of each monofilament is 40% or higher; CV indicating a variation in the strengths of the monofilaments is 25% or lower; the elongation at break is from 2.5% inclusive to 6.0% inclusive; the fineness of each filament is 10 dTex or less; and the melting point of the filaments is 145° C. or higher.
    Type: Grant
    Filed: March 12, 2004
    Date of Patent: October 12, 2010
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Tooru Kitagawa, Yasuo Ohta, Yasunori Fukushima, Hiroki Murase
  • Patent number: 7736564
    Abstract: A filament having excellent incision resistance includes as a primary component a polyethylene filament having a weight-average molecular weight of 300,000 or less and a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.0 or less as determined in the state of a filament as well as a modulus of 500 cN/dtex or more. This filament is useful to produce a fabric excellent in incision resistance, a fibrous material for reinforcing mortar or concrete, and a rope, each of which comprises the filament. The filament can be produced by drawing a non-drawn polyolefin filament which comprises a polyethylene having a weight-average molecular weight of 60,000-600,000, a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.5 or less, and a rate of birefringence (?n) of 0.008 or more, at a temperature not higher than the ?-relaxation temperature of the non-drawn filament.
    Type: Grant
    Filed: March 20, 2007
    Date of Patent: June 15, 2010
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Syoji Oda, Hiroki Murase
  • Publication number: 20090269581
    Abstract: A polyethylene fiber having high strength and extremely high productivity is difficult to obtain by conventional gel spinning methods. This high strength polyethylene fiber includes an ultrahigh molecular weight polyethylene resin having an intrinsic viscosity of 8 dL/g or more and contains a poor solvent in an amount of 10 ppm or more with respect to the resin. This high strength polyethylene fiber may also contain an ultrahigh molecular weight polyethylene resin having an intrinsic viscosity of 8 dL/g or more in which the resin contains a non-solvent in which the resin is insoluble in an amount of 10 ppm or more.
    Type: Application
    Filed: March 22, 2007
    Publication date: October 29, 2009
    Applicant: Toyo Boseki Kabushiki Kaisha
    Inventors: Yasunori Fukushima, Godo Sakamoto, Ihachiro Iba
  • Publication number: 20070237951
    Abstract: A polyethylene fiber having high strength, which was not easily obtained by methods such as the conventional gel spinning method, includes crystals derived from a monoclinic crystal having a size of 9 nm or more. The tensile strength of the fiber can be 30 cN/dtex or more. This high strength polyethylene fiber is produced by mixing an ultrahigh molecular weight polyethylene with a mixed solvent of a good solvent for polyethylene and a poor solvent for polyethylene to form a polyethylene dope, extruding the dope through an orifice, cooling the extruded dope, and drawing it into a filament yarn.
    Type: Application
    Filed: April 5, 2007
    Publication date: October 11, 2007
    Applicant: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Yasunori Fukushima
  • Publication number: 20070190321
    Abstract: A filament having excellent incision resistance includes as a primary component a polyethylene filament having a weight-average molecular weight of 300,000 or less and a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.0 or less as determined in the state of a filament as well as a modulus of 500 cN/dtex or more. This filament is useful to produce a fabric excellent in incision resistance, a fibrous material for reinforcing mortar or concrete, and a rope, each of which comprises the filament. The filament can be produced by drawing a non-drawn polyolefin filament which comprises a polyethylene having a weight-average molecular weight of 60,000-600,000, a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.5 or less, and a rate of birefringence (?n) of 0.008 or more, at a temperature not higher than the ?-relaxation temperature of the non-drawn filament.
    Type: Application
    Filed: March 20, 2007
    Publication date: August 16, 2007
    Applicant: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Syoji Oda, Hiroki Murase
  • Patent number: 7247372
    Abstract: The invention relates to a filament excellent in incision resistance comprising as a primary component a polyethylene filament having a weight-average molecular weight of 300,000 or less and a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.0 or less as determined in the state of a filament as well as a modulus of 500 cN/dtex or more, and to a fabric excellent in incision resistance, a fibrous material for reinforcing cement mortar or concrete, and a rope, each of which comprises the filament. The filament can be produced by drawing a non-drawn polyolefin filament which comprises a polyethylene having a weight-average molecular weight of 60,000-600,000, a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.5 or less, and a rate of birefringence (?n) of 0.008 or more, at a temperature not higher than the ?-relaxation temperature of said non-drawn filament.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: July 24, 2007
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Syoji Oda, Hiroki Murase
  • Publication number: 20070148452
    Abstract: PURPOSE: To provide a novel high strength polyethylene multifilament which consists of a plurality of filaments having high strengths and uniform internal structures, and showing a narrow variation in the strengths of the monofilaments, and which has been difficult to be provided by the conventional gel spinning method. SOLUTION: A high strength polyethylene multifilament consisting of a plurality of filaments which are characterized in that the crystal size of monoclinic crystal is 9 nm or less; the stress Raman shift factor is ?5.0 cm?1/(cN/dTex) or more; the average strength is 20 CN/dTex or higher; the knot strength retention of each monofilament is 40% or higher; CV indicating a variation in the strengths of the monofilaments is 25% or lower; the elongation at break is from 2.5% inclusive to 6.0% inclusive; the fineness of each filament is 10 dTex or less; and the melting point of the filaments is 145° C. or higher.
    Type: Application
    Filed: March 12, 2004
    Publication date: June 28, 2007
    Inventors: Godo Sakamoto, Tooru Kitagawa, Yasuo Ohta, Yasunori Fukushima, Hiroki Murase
  • Patent number: 7141301
    Abstract: A high strength polyethylene filament, wherein said filament has a fineness of 1.5 dtex or less as a monofilament, a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, the rate of dispersion-defective fibers cut from the filament is 2% or less, is disclosed, and a high strength polyethylene filament, wherein said filament has a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, a long period structure of 100 ? or less is observed in an X-ray small angle scattering pattern is disclosed.
    Type: Grant
    Filed: April 15, 2005
    Date of Patent: November 28, 2006
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Tooru Kitagawa, Syoji Oda, Yasuo Ohta
  • Patent number: 7056579
    Abstract: A high strength polyethylene filament having tenacity of at least 15 cN/dTex, which comprises a polyethylene having a weight-average molecular weight of 300,000 or less and a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.0 or less as determined in a state of the filament, and containing 0.01 to 3.0 branched chains per 1,000 backbone carbon atoms. When cut fibers are obtained by cutting the polyethylene filament, a rate of dispersion-defective fibers is 2.0% or less.
    Type: Grant
    Filed: August 2, 2002
    Date of Patent: June 6, 2006
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Syoji Oda, Yoshihiko Teramoto
  • Publication number: 20050238875
    Abstract: A high strength polyethylene filament, wherein said filament has a fineness of 1.5 dtex or less as a monofilament, a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, the rate of dispersion-defective fibers cut from the filament is 2% or less, is disclosed, and a high strength polyethylene filament, wherein said filament has a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, a long period structure of 100 ? or less is observed in an X-ray small angle scattering pattern is disclosed.
    Type: Application
    Filed: April 15, 2005
    Publication date: October 27, 2005
    Applicant: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Tooru Kitagawa, Syoji Oda, Yasuo Ohta
  • Patent number: 6958187
    Abstract: High strength polyethylene fibers and their applications, for example, chopped fibers, ropes, nets, ballistic materials or items, protective gloves, fiber reinforced concrete products, helmets, and other products obtained therefrom, in which the fiber is characterized in that: it contains a high molecular weight polyethylene consisting essentially of a repeating unit of ethylene; it has an intrinsic viscosity number of 5 or larger and an average strength of 22 cN/dtex or higher; and the measurement of the fiber by differential scanning calorimetry (DSC) exhibits a temperature-increasing DCS curve having at least one endothermic peak over a temperature region of 140° C. to 148° C. (on the low temperature side) and at least one endothermic peak over a temperature region of 148° C.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: October 25, 2005
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Yasuo Ohta, Godo Sakamoto, Tadayo Miyasaka, Takayoshi Okano, Junichi Nakahashi, Yukihiro Nomura, Takuya Konishi
  • Publication number: 20050118418
    Abstract: The invention relates to a filament excellent in incision resistance comprising as a primary component a polyethylene filament having a weight-average molecular weight of 300,000 or less and a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.0 or less as determined in the state of a filament as well as a modulus of 500 cN/dtex or more, and to a fabric excellent in incision resistance, a fibrous material for reinforcing cement mortar or concrete, and a rope, each of which comprises the filament. The filament can be produced by drawing a non-drawn polyolefin filament which comprises a polyethylene having a weight-average molecular weight of 60,000-600,000, a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.5 or less, and a rate of birefringence (?n) of 0.008 or more, at a temperature not higher than the ?-relaxation temperature of said non-drawn filament.
    Type: Application
    Filed: April 4, 2003
    Publication date: June 2, 2005
    Applicant: TOYO BOSEKI KABUSHIKE KAISHA
    Inventors: Godo Sakamoto, Syoji Oda, Hiroki Murase
  • Patent number: 6899950
    Abstract: A high strength polyethylene filament, wherein said filament has a fineness of 1.5 dtex or less as a monofilament, a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, the rate of dispersion-defective fibers cut from the filament is 2% or less, is disclosed, and a high strength polyethylene filament, wherein said filament has a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, a long period structure of 100 ? or less is observed in an X-ray small angle scattering pattern is disclosed.
    Type: Grant
    Filed: December 7, 2001
    Date of Patent: May 31, 2005
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Godo Sakamoto, Tooru Kitagawa, Syoji Oda, Yasuo Ohta
  • Publication number: 20050003182
    Abstract: A high strength polyethylene filament having tenacity of at least 15 cN/dTex, which comprises a polyethylene having a weight-average molecular weight of 300,000 or less and a ratio of a weight-average molecular weight to a number-average molecular weight (Mw/Mn) of 4.0 or less as determined in a state of the filament, and containing 0.01 to 3.0 branched chains per 1,000 backbone carbon atoms. When cut fibers are obtained by cutting the polyethylene filament, a rate of dispersion-defective fibers is 2.0% or less.
    Type: Application
    Filed: August 2, 2002
    Publication date: January 6, 2005
    Inventors: Godo Sakamoto, Syoji Oda, Yoshihiko Teramoto
  • Patent number: 6770363
    Abstract: High strength polyethylene fibers and their applications, for example, chopped fibers, ropes, nets, ballistic materials or items, protective gloves, fiber reinforced concrete products, helmets, and other products obtained therefrom, in which the fiber is characterized in that: it contains a high molecular weight polyethylene consisting essentially of a repeating unit of ethylene; it has an intrinsic viscosity number of 5 or larger and an average strength of 22 cN/dtex or higher; and the measurement of the fiber by differential scanning calorimetry (DSC) exhibits a temperature-increasing DCS curve having at least one endothermic peak over a temperature region of 140° C. to 148° C. (on the low temperature side) and at least one endothermic peak over a temperature region of 148° C.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: August 3, 2004
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Takuya Konishi, Yasuo Ohta, Godo Sakamoto
  • Publication number: 20040062926
    Abstract: A high strength polyethylene filament, wherein said filament has a fineness of 1.5 dtex or less as a monofilament, a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, the rate of dispersion-defective fibers cut from the filament is 2% or less, is disclosed, and a high strength polyethylene filament, wherein said filament has a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, a long period structure of 100 Å or less is observed in an X-ray small angle scattering pattern is disclosed.
    Type: Application
    Filed: October 15, 2003
    Publication date: April 1, 2004
    Inventors: Godo Sakamoto, Tooru Kitagawa, Syoji Oda, Yasuo Ohta
  • Patent number: 6689462
    Abstract: The invention relates to high-strength polyethylene fibers of mainly ethylene component having an intrinsic viscosity [&eegr;], when fibrous, of no less than 5, and having a strength of no less than 20 g/d and an elasticity modulus of no less than 500 g/d, and, in the measurement of the temperature variance of the dynamic viscoelasticity of the fibers, the &ggr; dispersion loss modulus peak temperature is no greater than −110° C. and the loss tangent (tan &dgr;) is no greater than 0.03.
    Type: Grant
    Filed: May 12, 2003
    Date of Patent: February 10, 2004
    Assignee: DSM N.V.
    Inventors: Yasuo Ohta, Godo Sakamoto
  • Patent number: 6669889
    Abstract: The invention relates to high-strength polyethylene fibers of mainly ethylene component having an intrinsic viscosity [&eegr;], when fibrous, of no less than 5, and having a strength of no less than 20 g/d and an elasticity modulus of no less than 500 g/d, and, in the measurement of the temperature variance of the dynamic viscoelasticity of the fibers, the &ggr; dispersion loss modulus peak temperature is no greater than −110° C. and the loss tangent (tan &dgr;) is no greater than 0.03.
    Type: Grant
    Filed: March 13, 2001
    Date of Patent: December 30, 2003
    Assignee: DSM N.V.
    Inventors: Yasuo Ohta, Godo Sakamoto
  • Publication number: 20030211321
    Abstract: High strength polyethylene fibers and their applications, for example, chopped fibers, ropes, nets, ballistic materials or items, protective gloves, fiber reinforced concrete products, helmets, and other products obtained therefrom, in which the fiber is characterized in that: it contains a high molecular weight polyethylene consisting essentially of a repeating unit of ethylene; it has an intrinsic viscosity number of 5 or larger and an average strength of 22 cN/dtex or higher; and the measurement of the fiber by differential scanning calorimetry (DSC) exhibits a temperature-increasing DCS curve having at least one endothermic peak over a temperature region of 140° C. to 148° C. (on the low temperature side) and at least one endothermic peak over a temperature region of 148° C.
    Type: Application
    Filed: April 2, 2003
    Publication date: November 13, 2003
    Applicant: Toyo Boseki Kabushiki Kaisha
    Inventors: Yasuo Ohta, Godo Sakamoto, Tadayo Miyasaka, Takayoshi Okano, Junichi Nakahashi, Yukihiro Nomura, Takuya Konishi
  • Publication number: 20030207074
    Abstract: High strength polyethylene fibers and their applications, for example, chopped fibers, ropes, nets, ballistic materials or items, protective gloves, fiber reinforced concrete products, helmets, and other products obtained therefrom, in which the fiber is characterized in that: it contains a high molecular weight polyethylene consisting essentially of a repeating unit of ethylene; it has an intrinsic viscosity number of 5 or larger and an average strength of 22 cN/dtex or higher; and the measurement of the fiber by differential scanning calorimetry (DSC) exhibits a temperature-increasing DCS curve having at least one endothermic peak over a temperature region of 140° C. to 148° C. (on the low temperature side) and at least one endothermic peak over a temperature region of 148° C.
    Type: Application
    Filed: April 2, 2003
    Publication date: November 6, 2003
    Applicant: Toyo Boseki Kabushiki Kaisha
    Inventors: Yasuo Ohta, Godo Sakamoto, Tadayo Miyasaka, Takayoshi Okano, Junichi Nakahashi, Yukihiro Nomura, Takuya Konishi