Patents by Inventor Yuhei ISHIGAKI

Yuhei ISHIGAKI 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: 11993671
    Abstract: A chloroprene-unsaturated nitrile copolymer having 3 to 20% by mass of a structural unit derived from an unsaturated nitrile monomer, in which the chloroprene-unsaturated nitrile copolymer has a peak at 5.80 to 6.00 ppm in a 1H-NMR spectrum as measured in a deuterochloroform solvent, and a ratio (A/B) of a peak area (A) at 5.80 to 6.00 ppm and a peak area (B) at 4.05 to 6.20 ppm is 0.6/100 to 1.1/100.
    Type: Grant
    Filed: November 6, 2019
    Date of Patent: May 28, 2024
    Assignee: Denka Company Limited
    Inventors: Wataru Nishino, Suguru Onuki, Atsunori Kondo, Yuhei Ishigaki, Naoki Kobayashi
  • Patent number: 11965078
    Abstract: A chloroprene-unsaturated nitrile copolymer composition containing 100 parts by mass of a chloroprene-unsaturated nitrile copolymer having 3 to 20% by mass of a structural unit derived from an unsaturated nitrile monomer, and 0.05 to 2.0 parts by mass of a xanthogen compound.
    Type: Grant
    Filed: November 6, 2019
    Date of Patent: April 23, 2024
    Assignee: Denka Company Limited
    Inventors: Suguru Onuki, Wataru Nishino, Atsunori Kondo, Yuhei Ishigaki, Naoki Kobayashi
  • Publication number: 20230348646
    Abstract: A composition that serves as a binder for a positive electrode with a good balance between suppression of battery performance degradation at a high-capacity electrode, high-temperature storage property, and DC resistance, a slurry for a positive electrode using the composition, a positive electrode, and a secondary battery. A free induction decay curve of the composition obtained by measuring at 180° C. by Solid Echo method using pulse NMR is separated into three components, component S180, component M180, and component H180, a component ratio of the component S180 is 10% or more and 80% or less, and a relaxation time of the component S180 is 500 ?s or more.
    Type: Application
    Filed: August 11, 2021
    Publication date: November 2, 2023
    Applicant: DENKA COMPANY LIMITED
    Inventors: Yuhei ISHIGAKI, Ryosuke KANTO, Jun WATANABE
  • Publication number: 20230317951
    Abstract: A composition, serving as a binder with a good balance between suppression of battery performance degradation at a high-capacity electrode, high-temperature storage property, and DC resistance, a slurry for a positive electrode using the composition, a positive electrode, and a secondary battery. The composition includes a graft copolymer, wherein: the graft copolymer has a stem polymer and a branch polymer; the stem polymer contains a polyvinyl alcohol structure, the branch polymer contains a first monomer unit containing a (meth)acrylonitrile monomer unit and/or a (meth)acrylic acid monomer; the composition has a swelling rate to an electrolytic solution of 105 to 200% at 25° C. for 15 days; the swelling rate is a swelling rate after immersing the composition in the electrolytic solution at 25° C. for 15 days; and the electrolytic solution is obtained by mixing ethylene carbonate and diethyl carbonate at a volume ratio of 1:2.
    Type: Application
    Filed: August 11, 2021
    Publication date: October 5, 2023
    Applicant: DENKA COMPANY LIMITED
    Inventors: Ryosuke KANTO, Yuhei ISHIGAKI, Jun WATANABE
  • Publication number: 20230275233
    Abstract: A composition including a graft copolymer, wherein the graft copolymer has a stem polymer and a branch polymer; the stem polymer contains a polyvinyl alcohol structure, the branch polymer contains a first monomer unit containing a (meth)acrylonitrile monomer unit and/or a (meth)acrylic acid monomer; the composition has a gel fraction of 30% or more; the gel fraction is represented by following formula: the gel fraction %=A×100/1; A g is an insoluble content left on a filter pater when 1 g of the composition is added to 300 ml of dimethyl sulfoxide to obtain a mixture and the mixture is stirred at 60° C. for 15 hours and then filtered through the filter paper, which is a No. 5C filter paper as specified in JIS P 380.
    Type: Application
    Filed: August 11, 2021
    Publication date: August 31, 2023
    Applicant: DENKA COMPANY LIMITED
    Inventors: Ryosuke KANTO, Yuhei ISHIGAKI, Jun WATANABE
  • Patent number: 11566087
    Abstract: To provide a statistical copolymer containing a chloroprene monomer unit and an unsaturated nitrile monomer unit which has a satisfactory oil resistance. A method for producing a statistical copolymer containing a chloroprene monomer unit and an unsaturated nitrile monomer unit includes a step for conducting continuous addition or 10 cycles or more of intermittent portionwise addition of the chloroprene monomer after initiation of a polymerization reaction is provided. A rubber composition using a statistical copolymer according to the invention or a vulcanized molded article containing the rubber composition is excellent in terms of oil resistance, mechanical strength, compression set at a low temperature and flex fatigue resistance.
    Type: Grant
    Filed: May 11, 2018
    Date of Patent: January 31, 2023
    Assignee: DENKA COMPANY LIMITED
    Inventors: Wataru Nishino, Suguru Onuki, Kosuke Fujimoto, Yuhei Ishigaki, Shogo Hagiwara, Uichiro Yamagishi
  • Patent number: 11396572
    Abstract: Disclosed is a block copolymer including one or more blocks of an acrylate polymer and one or more blocks of a chloroprene polymer, wherein the number average molecular weight of the block copolymer is 110,000 or more, the number average molecular weight of the block of a chloroprene polymer is 80,000 or more in total, and the block copolymer has a functional group with a structure represented by the following chemical formula (1) or (2): wherein in the chemical formula (1), R1 represents hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group or a substituted, or unsubstituted heterocyclyl group.
    Type: Grant
    Filed: July 31, 2018
    Date of Patent: July 26, 2022
    Assignee: Denka Company Limited
    Inventors: Yuhei Ishigaki, Suguru Onuki, Shogo Hagiwara, Uichiro Yamagishi
  • Patent number: 11365276
    Abstract: To provide a block copolymer that includes an aromatic vinyl compound polymer and a chloroprene polymer, has a number average molecular weight of 100,000 or more, is preferred for a rubber composition and an adhesive composition, and is suitable for industrial production. A block copolymer includes at least one aromatic vinyl compound polymer block and at least one chloroprene polymer block, has a functional group with a structure represented by Chemical Formula (1) or (2), and has a number average molecular weight of 100,000 or more. The chloroprene polymer block has a number average molecular weight of 80,000 or more in total. (In Chemical Formula (1), R1 is hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclyl group.
    Type: Grant
    Filed: March 29, 2018
    Date of Patent: June 21, 2022
    Assignee: DENKA COMPANY LIMITED
    Inventors: Wataru Nishino, Yuhei Ishigaki, Takashi Aizawa, Shogo Hagiwara, Uichiro Yamagishi
  • Patent number: 11254807
    Abstract: Provided is a chloroprene-based polymer having an industrially applicable sufficient molecular weight and capable of obtaining a vulcanized rubber excellent in durability and fatigue endurance and an adhesive excellent in layer separation resistance. A chloroprene-based polymer having a number average molecular weight Mn of 150000 to 300000 and comprising a functional group of a structure represented by the general formula (1) or (2) below: (wherein in the general formula (1), R1 shows hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclyl group.
    Type: Grant
    Filed: July 20, 2018
    Date of Patent: February 22, 2022
    Assignee: Denka Company Limited
    Inventors: Yuhei Ishigaki, Shogo Hagiwara, Uichiro Yamagishi, Suguru Onuki, Kosuke Fujimoto, Wataru Nishino
  • Publication number: 20220010097
    Abstract: A chloroprene-unsaturated nitrile copolymer composition containing 100 parts by mass of a chloroprene-unsaturated nitrile copolymer having 3 to 20% by mass of a structural unit derived from an unsaturated nitrile monomer, and 0.05 to 2.0 parts by mass of a xanthogen compound.
    Type: Application
    Filed: November 6, 2019
    Publication date: January 13, 2022
    Applicant: DENKA COMPANY LIMITED
    Inventors: Suguru ONUKI, Wataru NISHINO, Atsunori KONDO, Yuhei ISHIGAKI, Naoki KOBAYASHI
  • Publication number: 20210395422
    Abstract: A chloroprene-unsaturated nitrile copolymer having 3 to 20% by mass of a structural unit derived from an unsaturated nitrile monomer, in which the chloroprene-unsaturated nitrile copolymer has a peak at 5.80 to 6.00 ppm in a 1H-NMR spectrum as measured in a deuterochloroform solvent, and a ratio (A/B) of a peak area (A) at 5.80 to 6.00 ppm and a peak area (B) at 4.05 to 6.20 ppm is 0.6/100 to 1.1/100.
    Type: Application
    Filed: November 6, 2019
    Publication date: December 23, 2021
    Applicant: DENKA COMPANY LIMITED
    Inventors: Wataru NISHINO, Suguru ONUKI, Atsunori KONDO, Yuhei ISHIGAKI, Naoki KOBAYASHI
  • Publication number: 20200207900
    Abstract: Disclosed is a block copolymer including one or more blocks of an acrylate polymer and one or more blocks of a chloroprene polymer, wherein the number average molecular weight of the block copolymer is 110,000 or more, the number average molecular weight of the block of a chloroprene polymer is 80,000 or more in total, and the block copolymer has a functional group with a structure represented by the following chemical formula (1) or (2): wherein in the chemical formula (1), R1 represents hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group or a substituted, or unsubstituted heterocyclyl group.
    Type: Application
    Filed: July 31, 2018
    Publication date: July 2, 2020
    Applicant: DENKA COMPANY LIMITED
    Inventors: Yuhei ISHIGAKI, Suguru ONUKI, Shogo HAGIWARA, Uichiro YAMAGISHI
  • Publication number: 20200199260
    Abstract: To provide a statistical copolymer containing a chloroprene monomer unit and an unsaturated nitrile monomer unit which has a satisfactory oil resistance. A method for producing a statistical copolymer containing a chloroprene monomer unit and an unsaturated nitrile monomer unit includes a step for conducting continuous addition or 10 cycles or more of intermittent portionwise addition of the chloroprene monomer after initiation of a polymerization reaction is provided. A rubber composition using a statistical copolymer according to the invention or a vulcanized molded article containing the rubber composition is excellent in terms of oil resistance, mechanical strength, compression set at a low temperature and flex fatigue resistance.
    Type: Application
    Filed: May 11, 2018
    Publication date: June 25, 2020
    Inventors: Wataru NISHINO, Suguru ONUKI, Kosuke FUJIMOTO, Yuhei ISHIGAKI, Shogo HAGIWARA, Uichiro YAMAGISHI
  • Publication number: 20200165421
    Abstract: Provided is a chloroprene-based polymer having an industrially applicable sufficient molecular weight and capable of obtaining a vulcanized rubber excellent in durability and fatigue endurance and an adhesive excellent in layer separation resistance. A chloroprene-based polymer having a number average molecular weight Mn of 150000 to 300000 and comprising a functional group of a structure represented by the general formula (1) or (2) below: (wherein in the general formula (1), R1 shows hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclyl group.
    Type: Application
    Filed: July 20, 2018
    Publication date: May 28, 2020
    Applicant: DENKA COMPANY LIMITED
    Inventors: Yuhei ISHIGAKI, Shogo HAGIWARA, Uichiro YAMAGISHI, Suguru ONUKI, Kosuke FUJIMOTO, Wataru NISHINO
  • Publication number: 20190389994
    Abstract: To provide a block copolymer that includes an aromatic vinyl compound polymer and a chloroprene polymer, has a number average molecular weight of 100,000 or more, is preferred for a rubber composition and an adhesive composition, and is suitable for industrial production. A block copolymer includes at least one aromatic vinyl compound polymer block and at least one chloroprene polymer block, has a functional group with a structure represented by Chemical Formula (1) or (2), and has a number average molecular weight of 100,000 or more. The chloroprene polymer block has a number average molecular weight of 80,000 or more in total.
    Type: Application
    Filed: March 29, 2018
    Publication date: December 26, 2019
    Inventors: Wataru NISHINO, Yuhei ISHIGAKI, Takashi AIZAWA, Shogo HAGIWARA, Uichiro YAMAGISHI
  • Patent number: 9328228
    Abstract: An object of the invention is to provide a chloroprene polymer composition resistant to discoloration under heat or light. Provided is a chloroprene rubber composition, prepared by carrying out emulsion polymerization in the presence of 0.5 to 7.0 parts by mass of a rosin acid salt as emulsifier and terminating the emulsion polymerization by addition of a polymerization inhibitor and a phosphorus- or phenol-based compound as antioxidant. It is possible according to the invention to obtain a chloroprene polymer composition superior in discoloration resistance under heat or light. The chloroprene polymer composition according to the present invention can be used favorably for adhesion of cloths, leathers, foamed sheets, papers, woods, shoe parts, and others.
    Type: Grant
    Filed: February 7, 2013
    Date of Patent: May 3, 2016
    Assignee: DENKA COMPANY LIMITED
    Inventors: Hiroyuki Yashima, Sachiyo Kishi, Kunihiko Otsuka, Yuhei Ishigaki
  • Publication number: 20160017130
    Abstract: An object of the invention is to provide a chloroprene polymer composition resistant to discoloration under heat or light. Provided is a chloroprene rubber composition, prepared by carrying out emulsion polymerization in the presence of 0.5 to 7.0 parts by mass of a rosin acid salt as emulsifier and terminating the emulsion polymerization by addition of a polymerization inhibitor and a phosphorus- or phenol-based compound as antioxidant. It is possible according to the invention to obtain a chloroprene polymer composition superior in discoloration resistance under heat or light. The chloroprene polymer composition according to the present invention can be used favorably for adhesion of cloths, leathers, foamed sheets, papers, woods, shoe parts, and others.
    Type: Application
    Filed: February 7, 2013
    Publication date: January 21, 2016
    Inventors: Hiroyuki YASHIMA, Sachiyo KISHI, Kunihiko OTSUKA, Yuhei ISHIGAKI