Patents Assigned to Kureha Corporation
  • Publication number: 20220089815
    Abstract: A method for continuously producing an aromatic polyether according to the present invention includes simultaneously implementing: a supply step of supplying a polymerization solvent, an alkali metal compound, and a raw material; a polymerizing step; and a movement step. The alkali metal compound is supplied as an aqueous mixture. According to the present invention, clogging of piping in the continuous production apparatus can be suppressed, and the aromatic polyether can be stably obtained.
    Type: Application
    Filed: December 12, 2019
    Publication date: March 24, 2022
    Applicant: Kureha Corporation
    Inventors: Toshiyuki KURIU, Tasutaka SUZUKI
  • Patent number: 11280153
    Abstract: A plug which does not cause an adverse effect such as failure of a member constituting the plug when a wellbore is plugged. The downhole plug (10) includes a mandrel (1) having a hollow structure, a sealing member (2) attached to an outer circumferential surface of the mandrel (1) and being deformable by exerted pressure, and a socket (3) attached, adjacent to the sealing member (2), onto the outer circumferential surface of the mandrel (1), downstream of where the pressure is exerted on the sealing member (2). An inner circumferential edge (31a) of the socket (3) which comes in contact with the mandrel (1) protrudes toward the sealing member (2).
    Type: Grant
    Filed: July 9, 2018
    Date of Patent: March 22, 2022
    Assignee: KUREHA CORPORATION
    Inventors: Seishiro Kobayashi, Teruaki Yoshii
  • Publication number: 20220073665
    Abstract: Provided is a resin composition that can suppress yellowing even when used in a transparent molded article having a large thickness. The resin composition according to the present invention contains a vinylidene fluoride polymer as a main component, and further contains an alkyl quaternary ammonium sulfate. A percentage of irregular sequences in the vinylidene fluoride polymer is 4% or greater.
    Type: Application
    Filed: October 18, 2019
    Publication date: March 10, 2022
    Applicant: Kureha Corporation
    Inventors: Tatsuaki MIYASHITA, Kazuyuki SUZUKI
  • Publication number: 20220064426
    Abstract: A polyvinylidene fluoride resin composition of the present invention contains an alkyl quaternary ammonium sulfate, an alkali metal concentration in the polyvinylidene fluoride resin composition is 60 ppm or less, and a hydrogen fluoride concentration in the polyvinylidene fluoride is 5 ppm or less. The polyvinylidene fluoride resin composition of the present invention can express sufficient transparency even in a thick molded article.
    Type: Application
    Filed: October 17, 2019
    Publication date: March 3, 2022
    Applicant: Kureha Corporation
    Inventors: Tatsuaki MIYASHITA, Kazuyuki SUZUKI
  • Publication number: 20220025121
    Abstract: In production of a polyarylene sulfide (PAS), combination/coalescence and enlargement of the PAS are prevented. A method for producing a PAS according to the present invention includes: first polymerization in which a mixture containing a sulfur source and a dihalo aromatic compound in an organic amide solvent is heated to initiate a polymerization reaction; second polymerization in which a first temperature (T1) is maintained after adding a phase separation agent to continue the reaction; third polymerization in which a second temperature (T2) is maintained to continue the reaction; and fourth polymerization in which the reaction is continued at a third temperature (T3), wherein a relationship among the temperatures is T1>T3>T2.
    Type: Application
    Filed: November 22, 2019
    Publication date: January 27, 2022
    Applicant: Kureha Corporation
    Inventors: Takeshi Sato, Ken-ichi Takaki, Yoshinori Suzuki
  • Patent number: 11203665
    Abstract: The production method of the present invention includes a step of supplying an organic polar solvent, a sulfur source, and a dihalo aromatic compound as reaction raw materials to at least one of a plurality of reaction vessels mutually communicated via a gas phase; a step of removing at least a portion of the water present in the reaction vessels; and a step of performing a polymerization reaction. These steps are carried out in parallel, and the reaction mixture is sequentially moved between reaction vessels. At that time, the internal temperatures of the reaction vessels are all not less than 150° C.
    Type: Grant
    Filed: August 21, 2020
    Date of Patent: December 21, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Michihisa Miyahara, Kenji Suzuki, Hiroshi Sakabe, Yoshikatsu Satake
  • Patent number: 11203666
    Abstract: Provided are a continuous production method and a continuous production apparatus utilizing the solution polycondensation for aromatic cyclic oligomers, which achieve a good space-time yield and are inexpensive and simple. The continuous production method includes: (a) supplying a polymerization solvent and a reaction raw material to a continuous production apparatus; (b) performing a polymerization reaction in the reaction vessels to form a reaction mixture; (c) removing water in gas phase parts of the reaction vessels from the reaction vessels; and (d) successively moving the reaction mixture to each of the reaction vessels; the steps (a), (b), (c), and (d) being performed in parallel; wherein an amount of the polymerization solvent in the reaction vessel positioned furthest downstream in a movement direction of the reaction mixture is not less than 1 L and not greater than 50 L per 1 mol of arylene units in the reaction raw material.
    Type: Grant
    Filed: October 11, 2018
    Date of Patent: December 21, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Kenji Suzuki, Michihisa Miyahara, Hiroshi Sakabe
  • Patent number: 11192905
    Abstract: Provided is a method for producing a cyclic polysilane compound simply and easily in a higher yield. The method for producing a cyclic polysilane compound according to an embodiment of the present invention comprising a reaction step of adding a silane monomer compound represented by Formula (I) below into a liquid mixture containing metallic sodium and a lithium salt and allowing them to react: where, R1 and R2 each independently represent a hydrogen atom, a hydrocarbon group, an alkoxy group, or a halogen atom, X1 and X2 each independently represent a halogen atom or an alkoxy group, and n1 is an integer that is greater than or equal to 1.
    Type: Grant
    Filed: August 30, 2019
    Date of Patent: December 7, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Ryota Naito, Hiraku Tohmiya, Eri Tamaki
  • Patent number: 11186531
    Abstract: The present invention is to provide a method of producing an alkene that can further enhance the yield of an alkene, a reaction product, the method including bringing a gaseous halogenated alkane into contact with an alkaline aqueous solution in the presence of a phase-transfer catalyst. The objective above is achieved by a method of producing an alkene comprising bringing in the presence of a phase-transfer catalyst a liquid phase containing an alkaline aqueous solution and a water-insoluble solvent into contact with a gas phase containing a halogenated alkane that is soluble in the water-insoluble solvent.
    Type: Grant
    Filed: October 18, 2018
    Date of Patent: November 30, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Kensuke Suzuki, Hiraku Tohmiya
  • Patent number: 11185840
    Abstract: The present invention provides a continuous polymerization apparatus capable of simply and efficiently separating a polymer and solid matter from a reaction mixture while having an apparatus configuration conducive to washing and maintenance, and a continuous production method for a polymer. A continuous polymerization apparatus (100) includes a plurality of reaction vessels (1a to 1c), wherein the plurality of reaction vessels are configured such that reaction mixtures (9a to 9c) successively move through each reaction vessel; in the plurality of reaction vessels, gas phase parts formed above the reaction mixture communicate with one another; and the continuous polymerization apparatus includes a washing part (5), the washing part configured to separate a solid included in the reaction mixture by sedimentation and to perform countercurrent washing.
    Type: Grant
    Filed: October 11, 2018
    Date of Patent: November 30, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Kenji Suzuki, Michihisa Miyahara, Hiroshi Sakabe, Yuichi Ishioka
  • Publication number: 20210367137
    Abstract: To provide a piezoelectric body film that can suppress decrease in the piezoelectric constant d31, a method of producing a piezoelectric body film, and a piezoelectric body device. A piezoelectric body film comprising a fluororesin as a piezoelectric material, the fluororesin containing, as a main constituent unit, a repeating unit derived from vinylidene fluoride, a piezoelectric constant d31 of the piezoelectric body film being 20 pC/N or greater, and an extrapolated onset temperature at start of shrinkage determined by TMA measurement being not lower than 90° C. and not higher than 115° C. The difference between piezoelectric constants d31 measured before and after heating the piezoelectric body film at 100° C. for 24 hours relative to the piezoelectric constant d31 before the heating for 24 hours is 20% or less.
    Type: Application
    Filed: October 19, 2018
    Publication date: November 25, 2021
    Applicant: Kureha Corporation
    Inventors: Yusuke SATO, Hisaaki TERASHIMA, Nobufumi SATO, Kazuyuki KANNO, Keiko AITA
  • Patent number: 11154835
    Abstract: The present invention provides a continuous polymerization apparatus capable of simply and efficiently separating a polymer and solid matter from a reaction mixture while having an apparatus configuration conducive to washing and maintenance, and a continuous production method for a polymer. A continuous polymerization apparatus (100) includes a plurality of reaction vessels (1a to 1c), wherein the plurality of reaction vessels are configured such that reaction mixtures (9a to 9c) successively move through each reaction vessel; in the plurality of reaction vessels, gas phase parts formed above the reaction mixture communicate with one another; and the continuous polymerization apparatus includes a washing part (5), the washing part configured to separate a solid included in the reaction mixture by sedimentation and to perform countercurrent washing.
    Type: Grant
    Filed: October 11, 2018
    Date of Patent: October 26, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Kenji Suzuki, Michihisa Miyahara, Hiroshi Sakabe, Yuichi Ishioka
  • Patent number: 11155682
    Abstract: The continuous dehydration method for a raw material mixture to be used in the production of PAS includes supply and dehydration of the raw material mixture and extraction of the raw material mixture having a water content reduced by the dehydration, the supply, dehydration and extraction being carried out concurrently in parallel. A dehydration efficiency index determined according to Equation (1) is not less than 0.3. In Equation (1), the dehydration time is a period of time until a moisture content per mole of the sulfur source in the raw material mixture having a reduced water content reaches not greater than 1.7 mol, including moisture consumed by the hydrolysis of the organic polar solvent.
    Type: Grant
    Filed: July 12, 2019
    Date of Patent: October 26, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Michihisa Miyahara, Kenji Suzuki, Hiroshi Sakabe
  • Publication number: 20210317720
    Abstract: A plug which does not cause an adverse effect such as failure of a member constituting the plug when a wellbore is plugged. A downhole plug (10) includes a mandrel (1) having a hollow structure, an annular sealing member (2) attached to an outer circumferential surface of the mandrel (1) and being deformable by exerted pressure, and an annular socket (3) attached, adjacent to the annular sealing member (2), onto the outer circumferential surface of the mandrel (1), downstream of where a pressure is exerted on the sealing member (2). The annular socket (3) is configured to include a socket-inner portion (31) which comes into contact with the outer circumferential surface of the mandrel (1), and a socket-outer portion (32) in an annular shape having an inner diameter equivalent to or larger than that of the socket-inner portion (31) and movably attached to the socket-inner portion (31). The socket-outer portion (32) includes a face facing the sealing member (2).
    Type: Application
    Filed: June 14, 2021
    Publication date: October 14, 2021
    Applicant: Kureha Corporation
    Inventors: Seishiro KOBAYASHI, Teruaki YOSHII
  • Patent number: 11142678
    Abstract: A downhole tool that has a high initial compressive strength, can maintain compressive strength for a certain period of time, and is rapidly degradable after use. The downhole tool is formed from a degradable resin composition containing a polyamide resin and a carboxylic acid anhydride, and the carboxylic acid anhydride is a compound satisfying the following melting point condition: melting point of polyamide resin?5% weight reduction temperature of carboxylic acid anhydride.
    Type: Grant
    Filed: June 6, 2019
    Date of Patent: October 12, 2021
    Assignee: Kureha Corporation
    Inventors: Fuminori Kobayashi, Hikaru Saijo
  • Patent number: 11136440
    Abstract: A vinylidene fluoride resin film is produced by using a film composition containing at least a vinylidene fluoride resin and organic particles. The vinylidene fluoride resin film includes a plurality of protrusions on at least one surface thereof. Among the plurality of protrusions, the number of protrusions greater than 0.10 ?m in height from a flat surface at which the protrusions are not present is from 40 to 400, per 0.10 mm2 of the vinylidene fluoride resin film.
    Type: Grant
    Filed: January 16, 2018
    Date of Patent: October 5, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Nobufumi Sato, Kazuyuki Kanno, Yusuke Sato, Keiko Aita, Hisaaki Terashima
  • Patent number: 11133506
    Abstract: Provided is a binder composition that exhibits sufficient adhesion and that achieves the excellent dispersibility of a conductive auxiliary agent. The binder composition according to an embodiment of the present invention is a binder composition containing a vinylidene fluoride copolymer composition containing vinylidene fluoride and an acrylic monomer; the acrylic monomer being at least one type selected from acrylic acid and methacrylic acid; and a ratio (Mn2/Mn1) of a number average molecular weight of the vinylidene fluoride copolymer composition after being adsorbed onto alumina (Mn2) to a number average molecular weight of the vinylidene fluoride copolymer composition before being adsorbed onto alumina (Mn1) being less than 2.
    Type: Grant
    Filed: May 18, 2017
    Date of Patent: September 28, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Yuki Sakai, Shintarou Kamata, Emi Sugawara
  • Patent number: 11117354
    Abstract: To provide a multilayer film that enables easy opening of a packaging material manufactured by deep draw forming. A multilayer film for deep draw forming, including: a vinylidene chloride copolymer resin layer as a middle layer; a crosslinked olefin resin layer as a first surface layer; and an ethylene/vinyl acetate copolymer resin layer as a second surface layer; where the ethylene/vinyl acetate copolymer resin layer is further provided either at least between the vinylidene chloride copolymer resin layer as the middle layer and crosslinked olefin resin layer as the first surface layer, or between the vinylidene chloride copolymer resin layer as the middle layer and ethylene/vinyl acetate copolymer resin layer as the second surface layer.
    Type: Grant
    Filed: September 6, 2016
    Date of Patent: September 14, 2021
    Assignee: KUREHA CORPORATION
    Inventors: Ichiro Kitada, Shota Nambu
  • Patent number: 11098288
    Abstract: An enzyme having the following characteristics (a) and (b): (a) the enzyme has an activity of reversible dehydrogenation of D-amino acids; (b) the enzyme is a hexamer of polypeptides having an amino acid sequence having 80% or greater identity to the amino acid sequence of SEQ ID NO: 2.
    Type: Grant
    Filed: August 9, 2018
    Date of Patent: August 24, 2021
    Assignees: KUREHA CORPORATION, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Hironaga Akita, Yuusuke Nakamichi, Masahiro Watanabe, Akinori Matsushika, Tomotake Morita
  • Publication number: 20210242448
    Abstract: Provided is a battery negative electrode material exhibiting both a merit of high specific capacity obtained by using Si, and a merit of high cycle durability obtained by using a non-graphitizable carbon material. Specifically, provided is a negative electrode material (1) of a battery that includes silicon material areas (10) made of a silicon material, and a carbon material area (20) made of a carbon material. The carbon material area (20) is formed in a surrounding area of the silicon material area (10), separated by a cavity (30) at least at a portion. In addition, an (002) average interlayer spacing d002 of the carbon material area (20) determined by powder X-ray diffraction is from 0.365 nm to 0.390 nm.
    Type: Application
    Filed: April 5, 2021
    Publication date: August 5, 2021
    Applicants: Kureha Corporation, Panasonic Corporation
    Inventors: Makoto IMAJI, Yukitaro SAKAKIBARA, Shota KOBAYASHI, Kenichi HOTEHAMA, Daisuke KATOU, Ryohei MIYAMAE