Patents by Inventor Yoshitaka Takezawa

Yoshitaka Takezawa 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: 11015020
    Abstract: An epoxy resin, comprising an epoxy compound, the epoxy compound comprising two or more structures represented by the following Formula (I) and at least one divalent biphenyl group: wherein, in Formula (I), each of R1 to R4 independently represents a hydrogen atom or an alkyl group having from 1 to 3 carbon atoms.
    Type: Grant
    Filed: October 14, 2016
    Date of Patent: May 25, 2021
    Assignee: Showa Denko Materials Co., Ltd.
    Inventors: Tomoko Higashiuchi, Naoki Maruyama, Yuka Yoshida, Kazumasa Fukuda, Yoshitaka Takezawa
  • Publication number: 20210139693
    Abstract: A resin composition, comprising: a thermosetting resin that has a mesogenic group in a molecule and that is capable of forming a smectic structure via a curing reaction; and mica.
    Type: Application
    Filed: April 4, 2017
    Publication date: May 13, 2021
    Inventors: Kazumasa FUKUDA, Yoshitaka TAKEZAWA, Tetsushi MARUYAMA, Yuka YOSHIDA
  • Publication number: 20210130537
    Abstract: An epoxy resin, comprising an epoxy compound having a mesogenic structure, the epoxy compound comprising a first epoxy compound having one biphenyl structure in a molecule and a second epoxy compound that is different from the first epoxy compound, at a mass ratio of the first epoxy compound to the second epoxy compound (first epoxy compound:second epoxy compound) of from 10:100 to 50:100.
    Type: Application
    Filed: March 5, 2018
    Publication date: May 6, 2021
    Applicant: Hitachi Chemical Company, Ltd.
    Inventors: Kazumasa FUKUDA, Yoshitaka TAKEZAWA, Naoki MARUYAMA, Yuka YOSHIDA, Tomoko HIGASHIUCHI
  • Patent number: 10988585
    Abstract: A resin sheet includes an epoxy resin including an epoxy resin oligomer and an epoxy resin monomer; a curing agent; and an inorganic filler, wherein a content of the inorganic filler is more than 30% by volume but less than 80% by volume.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: April 27, 2021
    Assignee: Showa Denko Materials Co., Ltd.
    Inventors: Tomoo Nishiyama, Yoshitaka Takezawa, Hideyuki Katagi, Kazuya Kiguchi
  • Patent number: 10941241
    Abstract: The present disclosure provides: an epoxy resin molding material including; an epoxy resin having a mesogen structure, a phenolic curing agent, an inorganic filler, and a curing accelerator having a quaternary phosphonium cation represented by the following Formula (I); a molded product and a molded cured product using the epoxy resin molding material; and a method for producing a molded cured product. In Formula (I), each of Ra to Rd independently represents an alkyl group having from 1 to 6 carbon atoms, or an aryl group, and the alkyl group and the aryl group may have a substituent.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: March 9, 2021
    Assignee: SHOWA DENKO MATERIALS CO., LTD.
    Inventors: Kenji Tanaka, Yuka Yoshida, Shinichi Kosugi, Shingo Tanaka, Hideyuki Katagi, Haruaki Sue, Yoshitaka Takezawa
  • Patent number: 10934387
    Abstract: An epoxy resin obtained by a reaction of an epoxy resin monomer having a mesogen backbone and having two glycidyl groups in one molecule with a divalent phenol compound having, as substituents, two hydroxyl groups on one benzene ring, in which a number average molecular weight in gel permeation chromatographic measurement is from 600 to 2,500.
    Type: Grant
    Filed: December 25, 2015
    Date of Patent: March 2, 2021
    Assignee: Showa Denko Materials Co., Ltd.
    Inventors: Hideyuki Katagi, Kenji Tanaka, Yoshitaka Takezawa, Haruaki Sue, Shinichi Kosugi
  • Publication number: 20210054133
    Abstract: A cured epoxy resin, which is a cured product of an epoxy compound having a mesogenic structure and a curing agent having a molecular chain or a flexible backbone with a molecular weight of 100 or more, the cured epoxy resin having a smectic structure; a cured epoxy resin, which is a cured product of an epoxy compound having a mesogenic structure and a curing agent having a molecular chain or a flexible backbone with a molecular weight of 100 or more, the cured epoxy resin not having a smectic structure; an epoxy resin composition, comprising an epoxy compound having a mesogenic structure and a curing agent having a molecular chain with a molecular weight of 100 or more; and an epoxy resin composition, comprising an epoxy compound having a mesogenic structure and a curing agent having a flexible backbone with a molecular weight of 100 or more.
    Type: Application
    Filed: August 30, 2017
    Publication date: February 25, 2021
    Applicant: Hitachi Chemical Company, Ltd.
    Inventors: Kazumasa FUKUDA, Yoshitaka TAKEZAWA, Naoki MARUYAMA, Yuka YOSHIDA, Tomoko HIGASHIUCHI
  • Publication number: 20210054136
    Abstract: Provided is an epoxy polymer which has a mesogen skeleton and a structural unit represented by Formula (A). In Formula (A), each R5 independently represents an alkyl group having from 1 to 8 carbon atoms, and n represents an integer of 0 to 3.
    Type: Application
    Filed: March 9, 2017
    Publication date: February 25, 2021
    Applicant: Hitachi Chemical Company, Ltd.
    Inventors: Hideyuki KATAGI, Naoki MARUYAMA, Yuka YOSHIDA, Tomoko HIGASHIUCHI, Yoshitaka TAKEZAWA
  • Patent number: 10920010
    Abstract: An epoxy resin, comprising a first epoxy compound having a mesogenic structure and a second epoxy compound having two or more mesogenic structures that are the same as the mesogenic structure of the first epoxy compound, a proportion, determined by liquid chromatography, of the first epoxy compound being from 40% to 50% with respect to a total amount of the epoxy resin.
    Type: Grant
    Filed: October 13, 2017
    Date of Patent: February 16, 2021
    Assignee: Showa Denko Materials Co., Ltd.
    Inventors: Naoki Maruyama, Tomoko Higashiuchi, Kazumasa Fukuda, Yuka Yoshida, Yoshitaka Takezawa
  • Publication number: 20200407888
    Abstract: An aspect of the present invention is an anisotropic thermal conductive resin fiber including a stretch fiber of a thermoplastic resin; and a thermal insulation material covering the stretch fiber.
    Type: Application
    Filed: February 27, 2019
    Publication date: December 31, 2020
    Applicant: HITACHI CHEMICAL COMPANY, LTD.
    Inventor: Yoshitaka TAKEZAWA
  • Publication number: 20200407617
    Abstract: An aspect of the present invention is an anisotropic thermal conductive resin member including a plurality of bundled thermoplastic resin stretch fibers.
    Type: Application
    Filed: February 27, 2019
    Publication date: December 31, 2020
    Applicants: HITACHI CHEMICAL COMPANY, LTD., THE UNIVERSITY OF TOKYO
    Inventors: Yoshitaka TAKEZAWA, Masahiro NOMURA
  • Publication number: 20200392282
    Abstract: An epoxy resin, comprising an epoxy compound having two or more mesogenic structures, and having a loss tangent of 1 or more at 35° C. before curing.
    Type: Application
    Filed: February 18, 2019
    Publication date: December 17, 2020
    Inventors: Naoki MARUYAMA, Tomoko HIGASHIUCHI, Kazumasa FUKUDA, Hideyuki KATAGI, Yuki NAKAMURA, Yoshitaka TAKEZAWA
  • Publication number: 20200385512
    Abstract: (1) An epoxy resin, which is configured to form, in a cured product of the epoxy resin, a phase-separated structure that is formed from at least two phases, wherein at least one phase of the at least two phases includes a liquid crystal structure and (2) An epoxy resin, which is configured to form a phase-separated structure in a cured product, the cured product being obtained by curing the epoxy resin by increasing a temperature of the epoxy resin from an ambient temperature to a curing temperature at a rate of not greater than 20° C./minute.
    Type: Application
    Filed: February 22, 2018
    Publication date: December 10, 2020
    Inventors: Kazumasa FUKUDA, Yoshitaka TAKEZAWA, Tomoko HIGASHIUCHI, Naoki MARUYAMA, Shingo TANAKA
  • Patent number: 10851200
    Abstract: Provided is a resin composition for forming a resin layer of a laminate by coating, the resin composition having a thixotropic index at 25° C. of from 3 to 10, and the laminate includes a pair of members and the resin layer arranged between the pair of members.
    Type: Grant
    Filed: November 8, 2019
    Date of Patent: December 1, 2020
    Assignee: SHOWA DENKO MATERIALS CO., LTD.
    Inventors: Kazuya Kiguchi, Tomoo Nishiyama, Yoshitaka Takezawa
  • Publication number: 20200324538
    Abstract: Provided is a method of producing a laminate, the method including: a resin layer forming step of forming a resin layer on a first member; and a member arranging step of arranging a second member on the resin layer, in which at least one of the following conditions (1) and (2) is satisfied: (1) the surface roughness (Rz) of a surface of the first member that contacts the resin layer is larger than the surface roughness (Rz) of a surface of the second member that contacts the resin layer; and (2) the surface of the second member that contacts the resin layer has a surface roughness (Rz) of 20 ?m or less.
    Type: Application
    Filed: May 31, 2017
    Publication date: October 15, 2020
    Inventors: Tomoo NISHIYAMA, Kazuya KIGUCHI, Yoshitaka TAKEZAWA
  • Publication number: 20200325398
    Abstract: An epoxy resin, comprising an epoxy compound having a mesogenic structure, and having a value of ??2/??1 equal to 3 or less, wherein is an initial dynamic shear viscosity (Pa·s) and ??2 is a maximum value of dynamic shear viscosity (Pa·s), in a measurement of dynamic shear viscosity.
    Type: Application
    Filed: April 9, 2019
    Publication date: October 15, 2020
    Applicant: Hitachi Chemical Company, Ltd.
    Inventors: Tomoko HIGASHIUCHI, Naoki MARUYAMA, Kazumasa FUKUDA, Yoshitaka TAKEZAWA, Hideyuki KATAGI, Yuki NAKAMURA
  • Patent number: 10800872
    Abstract: An epoxy resin, comprising an epoxy compound having a mesogen structure, wherein, when performing a process of decreasing a temperature of the epoxy resin from 150° C. to 30° C. at a rate of 2° C./min, and a process of increasing the temperature of the epoxy resin from 30° C. to 150° C. at a rate of 2° C./min, in this order, the epoxy resin has a maximum value of ??2/??1 of 20 or less within a temperature range of from 30° C. to 150° C., wherein ??1 is a dynamic shear viscosity (Pa·s) measured in the process of decreasing the temperature, and ??2 is a dynamic shear viscosity (Pa·s) measured in the process of increasing the temperature, ??1 and ??2 being measured at the same temperature, and a value ??2 measured at 100° C. is 1000 Pa·s or less.
    Type: Grant
    Filed: October 13, 2017
    Date of Patent: October 13, 2020
    Assignee: HITACHI CHEMICAL COMPANY, LTD.
    Inventors: Naoki Maruyama, Tomoko Higashiuchi, Kazumasa Fukuda, Yuka Yoshida, Yoshitaka Takezawa
  • Publication number: 20200270447
    Abstract: An epoxy resin, comprising an epoxy compound A that has at least two mesogenic structures and at least one phenylene group, and an epoxy compound B that has at least two mesogenic structures and at least one divalent biphenyl group.
    Type: Application
    Filed: September 29, 2017
    Publication date: August 27, 2020
    Applicant: Hitachi Chemical Company, Ltd.
    Inventors: Naoki MARUYAMA, Yuka YOSHIDA, Tomoko HIGASHIUCHI, Kazumasa FUKUDA, Keiichiro NISHIMURA, Yoshitaka TAKEZAWA
  • Publication number: 20200262969
    Abstract: An epoxy resin, comprising (1) an epoxy compound having two aromatic rings that form a divalent biphenyl structure and mesogenic structures that are bonded to the two aromatic rings, and at least one of the mesogenic structures being bonded to the aromatic ring at an angle with a molecular axis of the divalent biphenyl structure; (2) an epoxy compound having two aromatic rings that form a divalent biphenyl structure and mesogenic structures that are bonded to the two aromatic rings, and at least one of bonding sites of the aromatic ring to the mesogenic structure being at an ortho position or a meta position with respect to a carbon atom that bonds the aromatic rings; or (3) an epoxy compound having a phenylene group and two mesogenic structures that are bonded to the phenylene group at an angle with each other.
    Type: Application
    Filed: September 29, 2017
    Publication date: August 20, 2020
    Applicant: Hitachi Chemical Company, Ltd.
    Inventors: Tomoko HIGASHIUCHI, Naoki MARUYAMA, Yuka YOSHIDA, Kazumasa FUKUDA, Yoshitaka TAKEZAWA
  • Publication number: 20200247943
    Abstract: An epoxy resin, comprising an epoxy compound having at least two mesogenic structures and at least one divalent biphenyl group.
    Type: Application
    Filed: September 29, 2017
    Publication date: August 6, 2020
    Applicant: HITACHI CHEMICAL COMPANY, LTD.
    Inventors: Yuka YOSHIDA, Naoki MARUYAMA, Tomoko HIGASHIUCHI, Kazumasa FUKUDA, Keiichiro NISHIMURA, Yoshitaka TAKEZAWA