Patents by Inventor Kazuhiko Maekawa

Kazuhiko Maekawa 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: 11884756
    Abstract: A method of producing modified vinyl alcohol-based polymer particles, includes mixing vinyl alcohol-based polymer particles with a mixed medium containing unsaturated carboxylic acid, an acid catalyst, and water, wherein, by mixing the vinyl alcohol-based polymer particles with the mixed medium, the vinyl alcohol-based polymer particles are reacted with the unsaturated carboxylic acid to obtain modified vinyl alcohol-based polymer particles containing a vinyl ester unit represented by a formula (2) below, having a vinyl alcohol unit content based on the total constitutional units of 60 mol % or more and less than 95 mol %, and having an average particle diameter from 50 to 2000 ?m. The production method is capable of controlling the particle shape and does not cause the problem of the residual sulfur content, and is further convenient and economically advantageous.
    Type: Grant
    Filed: December 26, 2019
    Date of Patent: January 30, 2024
    Assignee: KURARAY CO., LTD.
    Inventors: Yuki Tachibana, Yusuke Amano, Yuki Shimizu, Kazuhiko Maekawa
  • Publication number: 20230226520
    Abstract: A block copolymer (A) including a vinyl alcohol-based polymer block (b) and an ionic polymer block (c) containing a monomer unit with an ionic group forming a salt and a vinyl alcohol-based monomer unit. The ionic group is a carboxylic acid group, a sulfonic acid group, or an ammonium group. The vinyl alcohol-based polymer block (b) has a number-average molecular weight (Mnb) from 15,000 to 220,000. The ionic polymer block (c) has a content of the vinyl alcohol-based monomer unit from 5 to 95 mol % based on the total monomer units. The block copolymer (A) has a number-average molecular weight (MnA) from 20,000 to 440,000. A ratio (Mnb/MnA) of the number-average molecular weight (Mnb) to the number-average molecular weight (MnA) is from 0.1 to 0.9.
    Type: Application
    Filed: June 7, 2021
    Publication date: July 20, 2023
    Applicant: KURARAY CO., LTD.
    Inventors: Takumi TAKAYAMA, Kazuhiko MAEKAWA, Kazutoshi MISHIMA
  • Publication number: 20230003501
    Abstract: A bend sensor comprising a sensor section in which a polymer electrolyte film is sandwiched between a pair of electrode films, wherein each of the electrode films contains: a block copolymer (Z) having a polymer block (S) composed of a structural unit derived from an aromatic vinyl compound, and containing an ion-conducting group, and an amorphous polymer block (T) composed of a structural unit derived from an unsaturated aliphatic hydrocarbon; and a conducting particle; which block copolymer (Z) forms a lamellar structure, which bend sensor therefore allows generation of enhanced voltage between the electrode films when deformation of the sensor occurs as it follows movement of an object, is provided.
    Type: Application
    Filed: September 6, 2022
    Publication date: January 5, 2023
    Applicant: NIPPON MEKTRON,LTD.
    Inventors: Mikiya MATSUURA, Katsuei TAKAHASHI, Naoki CHIKUGO, Kazuhiko MAEKAWA, Kenji SHACHI
  • Patent number: 11485811
    Abstract: The invention relates to particles with an average particle size of 300 to 1000 ?m, comprising a modified polyvinyl alcohol having vinyl alcohol units and structural units represented by formula (1), wherein a content of the vinyl alcohol units is 60 to 90 mol % based on the total structural units: wherein R1 represents a hydrogen atom or a methyl group. Thus, the present invention provides particles containing a modified polyvinyl alcohol having high water solubility and high affinity for a photosensitive monomer, which are highly photosensitive.
    Type: Grant
    Filed: February 18, 2019
    Date of Patent: November 1, 2022
    Assignee: KURARAY CO., LTD.
    Inventors: Yusuke Amano, Yuki Tachibana, Yuki Shimizu, Kazuhiko Maekawa
  • Publication number: 20220325013
    Abstract: The present invention provides a preparing method of a polymer which is low-toxic, environmental-friendly, highly controllable, and low cost to obtain a polymer with high molecular weight. The preparing method comprises conducting a controlled radical polymerization process of monomer (Y). In the controlled radical polymerization process, organic compound (A) which has the formula (I) and radical initiator (B) are existing in a mole ratio (B/A) ranged from 0.5 to 25, wherein R1 is a hydrogen atom, alkyl group, aryl group, or hydroxyl group, the alkyl group can be alkyl having substituents or alkyl substituent, and the aryl group can be aryl having substituents or aryl substituent.
    Type: Application
    Filed: March 25, 2022
    Publication date: October 13, 2022
    Inventors: Takumi Takayama, Kazuhiko Maekawa, Tomoya Hosoki, Chi-How Peng
  • Publication number: 20220267499
    Abstract: Disclosed is a vinyl alcohol-based block copolymer that is a block copolymer composed of a vinyl alcohol-based polymer block (B-b) and a copolymer block (B-c) comprising a vinyl alcohol-based monomer unit and an acrylic acid-based monomer unit, wherein a content (Z) of the acrylic acid-based monomer unit relative to all monomer units is 0.05 to 20.0 mol %, the block copolymer has a saponification degree of 80 to 99.99 mol %, the block copolymer has a number-average molecular weight (Mna) of 20,000 to 440,000, the block copolymer has a molecular weight distribution (Mwa/Mna) of 1.05 to 1.95, and a ratio (DPb/DPa) of a number-average polymerization degree (DPb) of the vinyl alcohol-based polymer block (B-b) to the number-average polymerization degree (DPa) of the block copolymer is 0.010 to 0.999.
    Type: Application
    Filed: June 25, 2020
    Publication date: August 25, 2022
    Applicant: KURARAY CO., LTD.
    Inventors: Takumi TAKAYAMA, Kazutoshi MISHIMA, Hiroyuki KONISHI, Kazuhiko MAEKAWA
  • Publication number: 20220220332
    Abstract: A coating composition may include a modified polyvinyl alcohol resin (A) having an ethylene unsaturated group in a side chain thereof. Examples of the modified polyvinyl alcohol resin (A) include those including a structural unit represented by formula (II) or (III). Substrates in various technical fields such as the resin molding field, automobile/railway/aircraft/ships-related field, medical product field, food field, agriculture/gardening field, electrical field, and construction field can be coated with such a coating composition.
    Type: Application
    Filed: April 24, 2020
    Publication date: July 14, 2022
    Applicant: Kuraray Co., Ltd.
    Inventors: Yuki TACHIBANA, Yusuke AMANO, Kazuhiko MAEKAWA
  • Publication number: 20220144977
    Abstract: A method of producing modified vinyl alcohol-based polymer particles, includes mixing vinyl alcohol-based polymer particles with a mixed medium containing unsaturated carboxylic acid, an acid catalyst, and water, wherein, by mixing the vinyl alcohol-based polymer particles with the mixed medium, the vinyl alcohol-based polymer particles are reacted with the unsaturated carboxylic acid to obtain modified vinyl alcohol-based polymer particles containing a vinyl ester unit represented by a formula (2) below, having a vinyl alcohol unit content based on the total constitutional units from 95 to 99.99 mol %, and having an average particle diameter from 50 to 2000 ?m. The production method does not cause the problem of the residual sulfur content derived from a liquid medium used for reaction and is also capable of modifying the vinyl alcohol-based polymer particles while maintaining the particle shape.
    Type: Application
    Filed: March 12, 2020
    Publication date: May 12, 2022
    Applicant: KURARAY CO., LTD.
    Inventors: Yuki TACHIBANA, Yusuke AMANO, Yuki SHIMIZU, Kazuhiko MAEKAWA
  • Publication number: 20220089793
    Abstract: A method of producing modified vinyl alcohol-based polymer particles, includes mixing vinyl alcohol-based polymer particles with a mixed medium containing unsaturated carboxylic acid, an acid catalyst, and water, wherein, by mixing the vinyl alcohol-based polymer particles with the mixed medium, the vinyl alcohol-based polymer particles are reacted with the unsaturated carboxylic acid to obtain modified vinyl alcohol-based polymer particles containing a vinyl ester unit represented by a formula (2) below, having a vinyl alcohol unit content based on the total constitutional units of 60 mol % or more and less than 95 mol %, and having an average particle diameter from 50 to 2000 ?m. The production method is capable of controlling the particle shape and does not cause the problem of the residual sulfur content, and is further convenient and economically advantageous.
    Type: Application
    Filed: December 26, 2019
    Publication date: March 24, 2022
    Applicant: KURARAY CO., LTD.
    Inventors: Yuki TACHIBANA, Yusuke AMANO, Yuki SHIMIZU, Kazuhiko MAEKAWA
  • Patent number: 11261270
    Abstract: A polyvinyl alcohol has a number-average molecular weight (Mn) from 4,400 to 440,000, a molecular weight distribution (Mw/Mn) from 1.05 to 1.70, a degree of saponification from 80 to 99.99 mol %, wherein the polyvinyl alcohol contains an end group represented by a formula (I) below, and a molar ratio (X) of the end group based on total monomer units and the number-average molecular weight (Mn) satisfy a formula (1) below. Such a polyvinyl alcohol has a narrow molecular weight distribution and a high number-average molecular weight with hue good. (In the formula, R1 denotes an optionally substituted aromatic group having a carbon number from 6 to 20, and R2 denotes a hydrogen atom, an alkyl group having a carbon number from 1 to 20, or an optionally substituted aromatic group having a carbon number from 6 to 20.) X·Mn/44?0.
    Type: Grant
    Filed: July 11, 2018
    Date of Patent: March 1, 2022
    Assignees: KURARAY CO., LTD., UNIVERSITE DE LIEGE
    Inventors: Takumi Takayama, Kazuhiko Maekawa, Christophe Detrembleur, Antoine Debuigne, Christine Jerome
  • Publication number: 20220049082
    Abstract: The present invention provides a resin composition having superior flexibility and that exhibits excellent durability in thermal molding, and a molded body of such a resin composition. The present invention relates to a resin composition comprising: a copolymer (B) constituted of a vinyl alcohol polymer (B-1) region and a diene polymer (B-2) region; and at least one compound selected from the group consisting of a phenol-based compound (C), an amine-based compound (D), and a phosphorus-based compound (E).
    Type: Application
    Filed: September 12, 2019
    Publication date: February 17, 2022
    Applicant: KURARAYCO., LTD.
    Inventors: Yusuke AMANO, Eiichi ISHIDA, Masayoshi YAMANAKA, Kazuhiko MAEKAWA
  • Patent number: 11111319
    Abstract: A polyvinyl alcohol has a number-average molecular weight (Mn) from 4,400 to 440,000, a molecular weight distribution (Mw/Mn) from 1.05 to 1.70, a degree of saponification from 80 to 99.99 mol %, and a carbon-carbon double bond content (X) of 0.1 mol % or less based on total monomer units, and satisfying a formula (1) below. A polyvinyl alcohol, having a narrow molecular weight distribution and a high number-average molecular weight with good hue, and a method for producing the same are thus provided.
    Type: Grant
    Filed: March 30, 2017
    Date of Patent: September 7, 2021
    Assignee: KURARAY CO., LTD.
    Inventors: Yusuke Amano, Takumi Takayama, Kazuhiko Maekawa
  • Publication number: 20210246299
    Abstract: The present invention provides a rubber composition having superior moldability, wear resistance, and grip performance, and tires therewith. The present invention relates to a rubber composition comprising: a copolymer (B) constituted of a vinyl alcohol polymer (B-1) region and a diene polymer (B-2) region; and a rubber component (C), wherein the rubber composition comprises 1 to 20 parts by mass of the copolymer (B) relative to 100 parts by mass of the rubber component (C).
    Type: Application
    Filed: June 7, 2019
    Publication date: August 12, 2021
    Applicant: KURARAYCO., LTD.
    Inventors: Yusuke AMANO, Eiichi ISHIDA, Kazuhiko MAEKAWA, Daisuke KODA, Hiroshi KANBARA
  • Patent number: 11078309
    Abstract: There is provided a vinyl alcohol-based polymer having an olefin in side chain, comprising 0.001 to 10 mol % of a structural unit represented by Formula (1) based on the total amount of structural units, wherein the total carbon number of X, R1, R2, R3 and R4 is 2 or more. The vinyl alcohol-based polymer having an olefin in side chain has excellent storage stability, good solubility in water or an organic solvent even after thermal treatment, and excellent reactivity to high energy beam.
    Type: Grant
    Filed: June 5, 2018
    Date of Patent: August 3, 2021
    Assignee: KURARAY CO., LTD.
    Inventors: Yuki Tachibana, Yusuke Amano, Kazuhiko Maekawa
  • Patent number: 11028200
    Abstract: The present invention relates to a vinyl alcohol-based polymer having an olefin in side chain, comprising a vinyl alcohol unit and a structural unit represented by Formula (I), wherein X represents a divalent saturated hydrocarbon group with 1 to 6 carbon atoms, optionally having a branched structure; Y represents a hydrogen atom or a saturated hydrocarbon group with 1 to 6 carbon atoms, optionally having a branched structure; and Z represents a hydrogen atom or a methyl group. Thus, there is provided a vinyl alcohol-based polymer having an olefin in side chain exhibiting higher water solubility even after thermal treatment, higher storage stability, and higher reactivity to high energy beam, and a method for producing it.
    Type: Grant
    Filed: December 26, 2017
    Date of Patent: June 8, 2021
    Assignee: KURARAY CO., LTD.
    Inventors: Yusuke Amano, Yuki Tachibana, Yuki Kosaka, Kazuhiko Maekawa
  • Publication number: 20200362078
    Abstract: The invention relates to particles with an average particle size of 300 to 1000 ?m, comprising a modified polyvinyl alcohol having vinyl alcohol units and structural units represented by formula (1), wherein a content of the vinyl alcohol units is 60 to 90 mol % based on the total structural units: wherein R1 represents a hydrogen atom or a methyl group. Thus, the present invention provides particles containing a modified polyvinyl alcohol having high water solubility and high affinity for a photosensitive monomer, which are highly photosensitive.
    Type: Application
    Filed: February 18, 2019
    Publication date: November 19, 2020
    Applicant: KURARAY CO., LTD.
    Inventors: Yusuke AMANO, Yuki TACHIBANA, Yuki SHIMIZU, Kazuhiko MAEKAWA
  • Publication number: 20200355486
    Abstract: A bend sensor comprising a sensor section in which a polymer electrolyte film is sandwiched between a pair of electrode films, wherein each of the electrode films contains: a block copolymer (Z) having a polymer block (S) composed of a structural unit derived from an aromatic vinyl compound, and containing an ion-conducting group, and an amorphous polymer block (T) composed of a structural unit derived from an unsaturated aliphatic hydrocarbon; and a conducting particle; which block copolymer (Z) forms a lamellar structure, which bend sensor therefore allows generation of enhanced voltage between the electrode films when deformation of the sensor occurs as it follows movement of an object, is provided.
    Type: Application
    Filed: May 26, 2020
    Publication date: November 12, 2020
    Applicant: NIPPON NEKTRON, LTD.T
    Inventors: Mikiya MATSUURA, Katsuei Takahashi, Naoki Chikugo, Kazuhiko Maekawa, Kenji Shachi
  • Patent number: 10766978
    Abstract: A polyvinyl alcohol is produced in a method comprising: a polymerization step comprising polymerizing vinyl ester monomers by controlled radical polymerization in the presence of a radical initiator and an organic cobalt complex to obtain a polymer solution containing a polyvinyl ester; an extraction step comprising extracting a cobalt complex from the polymer solution by contacting an aqueous solution containing a water-soluble ligand with the polymer solution; and a saponification step comprising saponifying the polyvinyl ester after the extraction step to obtain a polyvinyl alcohol. A method for producing a polyvinyl alcohol is thus provided that has a narrow molecular weight distribution and a high number-average molecular weight with good hue and further good solubility in water.
    Type: Grant
    Filed: March 30, 2017
    Date of Patent: September 8, 2020
    Assignees: KURARAY CO., LTD., UNIVERSITE DE LIEGE
    Inventors: Takumi Takayama, Yusuke Amano, Kazuhiko Maekawa, Christophe Detrembleur, Antoine Debuigne, Christine Jerome
  • Patent number: 10745491
    Abstract: Provided is a monoclonal antibody or a fragment thereof that selectively inhibits the enzymatic activity of vascular endothelial lipase and pharmaceutical compositions containing the same as an active ingredient useful for the treatment of arteriosclerosis or metabolic syndrome.
    Type: Grant
    Filed: January 11, 2019
    Date of Patent: August 18, 2020
    Assignee: SHIONOGI & CO., LTD.
    Inventors: Shoichi Naito, Junji Onoda, Tasuku Tsukamoto, Katsutoshi Yamada, Shoji Yamane, Yoshito Numata, Kazuhiko Maekawa, Tatsuya Takahashi
  • Publication number: 20200216584
    Abstract: A polyvinyl alcohol has a number-average molecular weight (Mn) from 4,400 to 440,000, a molecular weight distribution (Mw/Mn) from 1.05 to 1.70, a degree of saponification from 80 to 99.99 mol %, wherein the polyvinyl alcohol contains an end group represented by a formula (I) below, and a molar ratio (X) of the end group based on total monomer units and the number-average molecular weight (Mn) satisfy a formula (1) below. Such a polyvinyl alcohol has a narrow molecular weight distribution and a high number-average molecular weight with hue good. (In the formula, R1 denotes an optionally substituted aromatic group having a carbon number from 6 to 20, and R2 denotes a hydrogen atom, an alkyl group having a carbon number from 1 to 20, or an optionally substituted aromatic group having a carbon number from 6 to 20.) X·Mn/44?0.
    Type: Application
    Filed: July 11, 2018
    Publication date: July 9, 2020
    Applicants: KURARAY CO., LTD., UNIVERSITE DE LIEGE
    Inventors: Takumi TAKAYAMA, Kazuhiko MAEKAWA, Christophe DETREMBLEUR, Antoine DEBUIGNE, Christine JEROME