Patents by Inventor Toshihiro Shigematsu

Toshihiro Shigematsu 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).

  • Publication number: 20220158299
    Abstract: It is an object of the present invention to provide a lithium ion battery separator which can be made thin, is excellent in tensile strength and cuttability and has low internal resistance, a low incidence of internal short circuit failure and high cycle characteristics and a lithium ion battery including the separator. In a lithium ion battery separator containing heat-resistant fibers and synthetic resin short fibers, fibrillated heat-resistant fibers having a modified freeness of not more than 300 ml are contained as the heat-resistant fibers, and the content of the fibrillated heat-resistant fibers having a modified freeness of not more than 300 ml is not less than 1.0 mass % to less than 5.0 mass % based on the total of all the fiber components contained in the separator. Modified freeness: This is a value measured in accordance with JIS P8121-2:2012 except that an 80-mesh wire net having a wire diameter of 0.14 mm and an opening of 0.
    Type: Application
    Filed: January 31, 2022
    Publication date: May 19, 2022
    Applicant: MITSUBISHI PAPER MILLS LIMITED
    Inventor: Toshihiro SHIGEMATSU
  • Patent number: 11335972
    Abstract: It is an object of the present invention to provide a lithium ion battery separator which can be made thin, is excellent in tensile strength and cuttability and has low internal resistance, a low incidence of internal short circuit failure and high cycle characteristics and a lithium ion battery including the separator. In a lithium ion battery separator containing heat-resistant fibers and synthetic resin short fibers, fibrillated heat-resistant fibers having a modified freeness of not more than 300 ml are contained as the heat-resistant fibers, and the content of the fibrillated heat-resistant fibers having a modified freeness of not more than 300 ml is not less than 1.0 mass % to less than 5.0 mass % based on the total of all the fiber components contained in the separator. Modified freeness: This is a value measured in accordance with JIS P8121-2:2012 except that an 80-mesh wire net having a wire diameter of 0.14 mm and an opening of 0.
    Type: Grant
    Filed: December 18, 2017
    Date of Patent: May 17, 2022
    Assignee: MITSUBISHI PAPER MILLS LIMITED
    Inventor: Toshihiro Shigematsu
  • Publication number: 20210288382
    Abstract: It is an object of the present invention to provide a substrate for lithium ion battery separators which has high adhesion to an inorganic particle layer, can be made thin and is excellent in tensile strength and cuttability and a lithium ion battery separator including the substrate for lithium ion battery separators. The substrate for lithium ion battery separators which contains heat-resistant fibers and synthetic resin short fibers contains fibrillated heat-resistant fibers having a modified freeness of not more than 300 ml as the heat-resistant fibers and has a content of the fibrillated heat-resistant fibers having a modified freeness of not more than 300 ml of not less than 1.0 mass % to less than 5.0 mass % based on the total of all the fiber components contained in the substrate. The modified freeness is a value measured in accordance with JIS P8121-2:2012 except that an 80-mesh wire net having a wire diameter of 0.14 mm and an opening of 0.
    Type: Application
    Filed: September 1, 2017
    Publication date: September 16, 2021
    Applicant: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Toshihiro SHIGEMATSU, Tomohiro SATO, Makoto KATO, Masatoshi KITO, Noriko KASAI, Kukjin YOON, Wakana AIZAWA
  • Patent number: 10818898
    Abstract: A separator for electrochemical elements includes beaten solvent-spun cellulose fibers and rayon fibers having a fiber diameter of 9.5 ?m or less. More preferably, the separator for electrochemical elements has a content of the rayon fibers relative to all fibers of 10 to 25% by mass, and can be applied to electrochemical elements such as electric double layer capacitors, hybrid capacitors, redox capacitors, and lithium secondary batteries. The separator can provide low internal short circuit failure rates and high surface strength.
    Type: Grant
    Filed: May 1, 2017
    Date of Patent: October 27, 2020
    Assignee: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Toshihiro Shigematsu, Masatoshi Kito, Keisuke Ooyama
  • Publication number: 20200091486
    Abstract: It is an object of the present invention to provide a lithium ion battery separator which can be made thin, is excellent in tensile strength and cuttability and has low internal resistance, a low incidence of internal short circuit failure and high cycle characteristics and a lithium ion battery including the separator. In a lithium ion battery separator containing heat-resistant fibers and synthetic resin short fibers, fibrillated heat-resistant fibers having a modified freeness of not more than 300 ml are contained as the heat-resistant fibers, and the content of the fibrillated heat-resistant fibers having a modified freeness of not more than 300 ml is not less than 1.0 mass % to less than 5.0 mass % based on the total of all the fiber components contained in the separator. Modified freeness: This is a value measured in accordance with JIS P8121-2:2012 except that an 80-mesh wire net having a wire diameter of 0.14 mm and an opening of 0.
    Type: Application
    Filed: December 18, 2017
    Publication date: March 19, 2020
    Applicant: MITSUBISHI PAPER MILLS LIMITED
    Inventor: Toshihiro SHIGEMATSU
  • Publication number: 20190148697
    Abstract: A separator for electrochemical elements includes beaten solvent-spun cellulose fibers and rayon fibers having a fiber diameter of 9.5 ?m or less. More preferably, the separator for electrochemical elements has a content of the rayon fibers relative to all fibers of 10 to 25% by mass, and can be applied to electrochemical elements such as electric double layer capacitors, hybrid capacitors, redox capacitors, and lithium secondary batteries. The separator can provide low internal short circuit failure rates and high surface strength.
    Type: Application
    Filed: May 1, 2017
    Publication date: May 16, 2019
    Applicant: Mitsubishi Paper Mills Limited
    Inventors: Toshihiro SHIGEMATSU, Masatoshi KITO, Keisuke OOYAMA
  • Patent number: 10230087
    Abstract: A non-woven fabric base material for a lithium ion secondary battery separator composed mainly of a polyethylene terephthalate fiber, characterized in that the non-woven fabric base material comprises a polyethylene terephthalate binder fiber and a crystallized polyethylene terephthalate fiber, and the content of a polyethylene terephthalate binder fiber having a fiber length of 2.5 mm or less is 10 to 60 mass %.
    Type: Grant
    Filed: June 23, 2017
    Date of Patent: March 12, 2019
    Assignee: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Tomohiro Sato, Toshihiro Shigematsu, Makoto Kato, Kenji Hyodo, Wakana Aizawa
  • Publication number: 20170288190
    Abstract: A non-woven fabric base material for a lithium ion secondary battery separator composed mainly of a polyethylene terephthalate fiber, characterized in that the non-woven fabric base material comprises a polyethylene terephthalate binder fiber and a crystallized polyethylene terephthalate fiber, and the content of a polyethylene terephthalate binder fiber having a fiber length of 2.5 mm or less is 10 to 60 mass %.
    Type: Application
    Filed: June 23, 2017
    Publication date: October 5, 2017
    Applicant: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Tomohiro SATO, Toshihiro SHIGEMATSU, Makoto KATO, Kenji HYODO, Wakana AIZAWA
  • Patent number: 9768430
    Abstract: A non-woven fabric base material for a lithium ion secondary battery separator composed mainly of a polyethylene terephthalate fiber, characterized in that the non-woven fabric base material comprises a polyethylene terephthalate binder fiber and a crystallized polyethylene terephthalate fiber, and the content of a polyethylene terephthalate binder fiber having a fiber length of 2.5 mm or less is 10 to 60 mass %.
    Type: Grant
    Filed: January 28, 2014
    Date of Patent: September 19, 2017
    Assignee: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Tomohiro Sato, Toshihiro Shigematsu, Makoto Kato, Kenji Hyodo, Wakana Aizawa
  • Patent number: 9653717
    Abstract: A separator for electrochemical element, comprising a porous sheet that contains as a main fiber, a fibrillated solvent spun cellulose fiber with an average fiber length of 0.40 to 1.10 mm, has an average internal bond strength of 60 mJ or more in a thickness direction, and has a lowest internal bond strength of 30 mJ or more in the thickness direction, a process for producing the separator, and an electrochemical element using the separator. The separator for electrochemical element has strong mechanical strength and excellent processability.
    Type: Grant
    Filed: August 26, 2014
    Date of Patent: May 16, 2017
    Assignee: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Hiroo Kaji, Toshihiro Shigematsu
  • Patent number: 9570726
    Abstract: A base material for a lithium ion secondary battery separator provided by the present invention comprises a polyethylene terephthalate fiber, in which an average fiber diameter of the polyethylene terephthalate fiber is 9.0 ?m or less, a specific X-ray diffraction intensity derived from the polyethylene terephthalate fiber is 300 cps/(g/m2) or more, and a coefficient of variation of a specific X-ray diffraction intensity is 12.0% or less, and is excellent in the workability during production and excellent in mechanical strength, uniformity and handling in a subsequent treatment step.
    Type: Grant
    Filed: January 25, 2013
    Date of Patent: February 14, 2017
    Assignee: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Hiroo Kaji, Toshihiro Shigematsu, Nobuaki Hirota, Hiroshi Matsuda
  • Publication number: 20150372269
    Abstract: A non-woven fabric base material for a lithium ion secondary battery separator composed mainly of a polyethylene terephthalate fiber, characterized in that the non-woven fabric base material comprises a polyethylene terephthalate binder fiber and a crystallized polyethylene terephthalate fiber, and the content of a polyethylene terephthalate binder fiber having a fiber length of 2.5 mm or less is 10 to 60 mass %.
    Type: Application
    Filed: January 28, 2014
    Publication date: December 24, 2015
    Applicant: Mitsubishi Paper Mills Limited
    Inventors: Tomohiro SATO, Toshihiro SHIGEMATSU, Makoto KATO, Kenji HYODO, Wakana AIZAWA
  • Publication number: 20150064573
    Abstract: [Problem to be Solved] To provide a separator for electrochemical element that has strong mechanical strength and excellent processability, and to provide an electrochemical element using the separator for electrochemical element. [Means for Solving Problem] A separator for electrochemical element, comprising a porous sheet that contains as a main fiber, a fibrillated solvent spun cellulose fiber with an average fiber length of 0.40 to 1.10 mm, has an average internal bond strength of 60 mJ or more in a thickness direction, and has a lowest internal bond strength of 30 mJ or more in the thickness direction, a process for producing the separator, and an electrochemical element using the separator.
    Type: Application
    Filed: August 26, 2014
    Publication date: March 5, 2015
    Inventors: Hiroo KAJI, Toshihiro SHIGEMATSU
  • Publication number: 20150024250
    Abstract: A base material for a lithium ion secondary battery separator provided by the present invention comprises a polyethylene terephthalate fiber, in which an average fiber diameter of the polyethylene terephthalate fiber is 9.0 ?m or less, a specific X-ray diffraction intensity derived from the polyethylene terephthalate fiber is 300 cps/(g/m2) or more, and a coefficient of variation of a specific X-ray diffraction intensity is 12.0% or less, and is excellent in the workability during production and excellent in mechanical strength, uniformity and handling in a subsequent treatment step.
    Type: Application
    Filed: January 25, 2013
    Publication date: January 22, 2015
    Applicant: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Hiroo Kaji, Toshihiro Shigematsu, Nobuaki Hirota, Hiroshi Matsuda
  • Patent number: 7405172
    Abstract: The present invention provides a non-woven fabric for an alkaline battery separator comprising semi-aromatic polyamide fibers comprising a dicarboxylic acid component, in which 60 mol % or more of the dicarboxylic acid component is an aromatic carboxylic acid component, and a diamine component, in which 60 mol % or more of the diamine component is an aliphatic alkylene diamine having 6 to 12 carbon atoms, and ethylene/vinyl alcohol copolymer fibers; wherein, the separator non-woven fabric has superior alkaline resistance in which the weight loss rate after 20 days is 5% or less in an alkaline resistance test at 90° C. in aqueous KOH solution having a specific gravity of 1.30. Consequently, since the present invention enables rapid charging and large-current discharging while also allowing thickness to be reduced for higher capacity, it can be preferably used as a non-woven fabric for an alkaline battery separator.
    Type: Grant
    Filed: May 22, 2003
    Date of Patent: July 29, 2008
    Assignees: Mitsubishi Paper Mills Limited, Kuraray Co., Ltd.
    Inventors: Toshihiro Shigematsu, Shigehiro Maeda, Takashi Katayama
  • Publication number: 20050221708
    Abstract: The present invention provides a non-woven fabric for an alkaline battery separator comprising semi-aromatic polyamide fibers comprising a dicarboxylic acid component, in which 60 mol % or more of the dicarboxylic acid component is an aromatic carboxylic acid component, and a diamine component, in which 60 mol % or more of the diamine component is an aliphatic alkylene diamine having 6 to 12 carbon atoms, and ethylene/vinyl alcohol copolymer fibers; wherein, the separator non-woven fabric has superior alkaline resistance in which the weight loss rate after 20 days is 5% or less in an alkaline resistance test at 90° C. in aqueous KOH solution having a specific gravity of 1.30. Consequently, since the present invention enables rapid charging and large-current discharging while also allowing thickness to be reduced for higher capacity, it can be preferably used as a non-woven fabric for an alkaline battery separator.
    Type: Application
    Filed: May 22, 2003
    Publication date: October 6, 2005
    Inventors: Toshihiro Shigematsu, Shigehiro Maeda, Takashi Katayama
  • Patent number: 6905798
    Abstract: The present invention provide a separator for an electrochemical device which comprises a wet nonwoven fabric comprising one or more kinds of fibrillated organic fibers which are at least partially fibrillated into a fiber diameter of 1 ?m or less, and one or more kinds of unfibrillated organic fibers having a fineness of 0.5 dtex or less, which exhibits excellent heat resistance, electrolyte holding properties, internal short-circuit preventing property, and winding property, which results in a lowered internal resistance and prolonged life of an electrochemical device, and a method for producing the same and an electrochemical device.
    Type: Grant
    Filed: May 29, 2001
    Date of Patent: June 14, 2005
    Assignee: Mitsubishi Paper Mills Limited
    Inventors: Takahiro Tsukuda, Masatoshi Midorikawa, Mitsuo Yoshida, Toshihiro Shigematsu, Kazuchiyo Takaoka, Kenji Hyodo
  • Publication number: 20030180622
    Abstract: The present invention provide a separator for an electrochemical device which comprises a wet nonwoven fabric comprising one or more kinds of fibrillated organic fibers which are at least partially fibrillated into a fiber diameter of 1 &mgr;m or less, and one or more kinds of. unfibrillated organic fibers having a fineness of 0.5 dtex or less, which exhibits excellent heat resistance, electrolyte holding properties, internal short-circuit preventing property, and winding property, which results in a lowered internal resistance and prolonged life of an electrochemical device, and a method for producing the same and an electrochemical device.
    Type: Application
    Filed: November 27, 2002
    Publication date: September 25, 2003
    Inventors: Takahiro Tsukuda, Masatoshi Midorikawa, Mitsuo Yoshida, Toshihiro Shigematsu, Kazuchiyo Takaoka, Kenji Hyodo
  • Patent number: 6080471
    Abstract: The present invention provides a non-woven fabric for an alkali cell separator capable of preventing active materials from transfer, and having distinguished electrolyte solution absorbability and retainability in spite of a small areal weight and also provides a process for producing the same. The non-woven fabric is substantially free from perforations and has a center surface average roughness SRa of not more than 13 .mu.m at streaks of entanglement on at least one side of the non-woven fabric, a maximum pore diameter of not more than 50 .mu.m and a water absorbability under pressure of not less than 20 g/m.sup.2, and a standard deviation of pore diameter distribution of not more than 20 .mu.m, as determined by bubble point method.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: June 27, 2000
    Assignee: Mitsubishi Paper Mills Limited
    Inventors: Toshihiro Shigematsu, Yoshitami Ishikawa, Yasuyuki Oku