Patents by Inventor Toshikatsu Mitsunaga

Toshikatsu Mitsunaga 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: 20220306904
    Abstract: A hot melt adhesive composition which can realize moderate adhesive strength with respect to the adherend when porous substrate is used, the composition, including: a styrene-based block copolymer; a tackifier; and a plasticizer; wherein: the styrene-based block copolymer is a styrene-butadiene block copolymer and a butadiene portion thereof is partially hydrogenated; the tackifier is contained by 65 to 190 parts by mass with respect to 100 parts by mass of the styrene-based block copolymer; and the plasticizer is contained by 0.1 to 24 parts by mass with respect to 100 parts by mass of the styrene-based block copolymer.
    Type: Application
    Filed: September 24, 2020
    Publication date: September 29, 2022
    Applicant: DENKA COMPANY LIMITED
    Inventors: Yoshiaki YAMAMOTO, Akiyoshi KIMURA, Yosuke TATE, Toshikatsu MITSUNAGA
  • Patent number: 10487013
    Abstract: Provided is a ceramic-resin composite body that has good mass productivity and product properties (heat dissipation properties, insulation properties and adhesive properties), and particularly a ceramic-resin composite that can dramatically improve the heat dissipation properties for electronic devices. The ceramic-resin composite body includes: 35 to 70% by volume of a sintered body having a monolithic structure in which non-oxide ceramic primary particles having an average major diameter of from 3 to 60 ?m and an aspect ratio of from 5 to 30 are three-dimensionally continuous; and 65 to 30% by volume of a thermosetting resin composition having an exothermic onset temperature of 180° C. or more and a curing rate of from 5 to 60% as determined with a differential scanning calorimeter, and having a number average molecular weight of from 450 to 4800, wherein the sintered body is impregnated with the thermosetting resin composition.
    Type: Grant
    Filed: March 10, 2017
    Date of Patent: November 26, 2019
    Assignee: Denka Company Limited
    Inventors: Taiki Nishi, Hideki Hirotsuru, Toshikatsu Mitsunaga, Saori Inoue
  • Patent number: 10377676
    Abstract: A resin-impregnated boron nitride sintered body having superior thermal conductivity and superior strength, and a resin-impregnated boron nitride sintered body having superior conductivity and small anisotropy of thermal conductivity are provided. A resin-impregnated boron nitride sintered body, including: 30 to 90 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally; and 10 to 70 volume % of a resin; wherein the boron nitride sintered body has a porosity of 10 to 70%; the boron nitride particles of the boron nitride sintered body has an average long diameter of 10 ?m or more; the boron nitride sintered body has a graphitization index by powder X-ray diffractometry is 4.0 or less; and an orientation degree of the boron nitride particles of the boron nitride sintered body by I.O.P is 0.01 to 0.
    Type: Grant
    Filed: October 19, 2016
    Date of Patent: August 13, 2019
    Assignee: Denka Company Limited
    Inventors: Koki Ikarashi, Shuhei Nonaka, Toshikatsu Mitsunaga, Hideki Hirotsuru, Mitsuru Shiiba
  • Publication number: 20190092695
    Abstract: Provided is a ceramic-resin composite body that has good mass productivity and product properties (heat dissipation properties, insulation properties and adhesive properties), and particularly a ceramic-resin composite that can dramatically improve the heat dissipation properties for electronic devices. The ceramic-resin composite body includes: 35 to 70% by volume of a sintered body having a monolithic structure in which non-oxide ceramic primary particles having an average major diameter of from 3 to 60 ?m and an aspect ratio of from 5 to 30 are three-dimensionally continuous; and 65 to 30% by volume of a thermosetting resin composition having an exothermic onset temperature of 180° C. or more and a curing rate of from 5 to 60% as determined with a differential scanning calorimeter, and having a number average molecular weight of from 450 to 4800, wherein the sintered body is impregnated with the thermosetting resin composition.
    Type: Application
    Filed: March 10, 2017
    Publication date: March 28, 2019
    Inventors: Taiki Nishi, Hideki Hirotsuru, Toshikatsu Mitsunaga, Saori Inoue
  • Patent number: 10087112
    Abstract: A resin-impregnated boron nitride sintered body having superior thermal conductivity and superior strength, and a resin-impregnated boron nitride sintered body having superior conductivity and small anisotropy of thermal conductivity are provided. A resin-impregnated boron nitride sintered body, including: 30 to 90 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally; and 10 to 70 volume % of a resin; wherein the boron nitride sintered body has a porosity of 10 to 70%; the boron nitride particles of the boron nitride sintered body has an average long diameter of 10 ?m or more; the boron nitride sintered body has a graphitization index by powder X-ray diffractometry is 4.0 or less; and an orientation degree of the boron nitride particles of the boron nitride sintered body by I.O.P is 0.01 to 0.
    Type: Grant
    Filed: June 2, 2014
    Date of Patent: October 2, 2018
    Assignee: Denka Company Limited
    Inventors: Koki Ikarashi, Shuhei Nonaka, Toshikatsu Mitsunaga, Hideki Hirotsuru, Mitsuru Shiiba
  • Patent number: 9656868
    Abstract: Provided is a boron-nitride powder that is suitable for use in a resin composition for transmitting heat from a heat-producing electronic component such as a power device to a heat-dissipating member. The boron-nitride powder reduces thermal-conductivity anisotropy and thermal contact resistance, resulting in high thermal conductivity, and contains boron-nitride particles each consisting of hexagonal boron-nitride primary particles joined together. The boron-nitride powder, which is an aggregate of said boron-nitride particles, exhibits a mean sphericity of at least 0.70, a mean particle diameter of 20-100 ?m, a porosity of 50-80%, a mean pore diameter of 0.10-2.0 ?m, a maximum pore diameter of at most 10 ?m, and a calcium content of 500-5,000 ppm. Under X-ray powder diffraction, the graphitization index of the boron-nitride powder is preferably between 1.6 and 4.0, inclusive, and the peak intensity ratio (I(002)/I(100)) between the (002) plane and the (100) plane is preferably at most 9.0.
    Type: Grant
    Filed: March 7, 2014
    Date of Patent: May 23, 2017
    Assignee: DENKA COMPANY LIMITED
    Inventors: Taiki Nishi, Koki Ikarashi, Toshikatsu Mitsunaga
  • Publication number: 20170036963
    Abstract: A resin-impregnated boron nitride sintered body having superior thermal conductivity and superior strength, and a resin-impregnated boron nitride sintered body having superior conductivity and small anisotropy of thermal conductivity are provided. A resin-impregnated boron nitride sintered body, including: 30 to 90 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally; and 10 to 70 volume % of a resin; wherein the boron nitride sintered body has a porosity of 10 to 70%; the boron nitride particles of the boron nitride sintered body has an average long diameter of 10 ?m or more; the boron nitride sintered body has a graphitization index by powder X-ray diffractometry is 4.0 or less; and an orientation degree of the boron nitride particles of the boron nitride sintered body by I.O.P is 0.01 to 0.
    Type: Application
    Filed: October 19, 2016
    Publication date: February 9, 2017
    Applicant: Denka Company Limited
    Inventors: Koki Ikarashi, Shuhei Nonaka, Toshikatsu Mitsunaga, Hideki Hirotsuru, Mitsuru Shiiba
  • Patent number: 9516741
    Abstract: A boron nitride/resin composite circuit board having high heat dissipation characteristics and high reliability is provided. A boron nitride/resin composite circuit board, including: a plate-shaped resin-impregnated boron nitride sintered body having a plate thickness of 0.2 to 1.5 mm, the plate-shaped resin-impregnated boron nitride sintered body including 30 to 85 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally, the boron nitride particles having an average long diameter of 5 to 50 ?m, and 70 to 15 volume % of a resin; and a metal circuit adhered onto both principal planes of the plate-shaped resin-impregnated boron nitride sintered body, the metal circuit being copper or aluminum, wherein: a ratio of a linear thermal expansion coefficient in a plane direction of the resin-impregnated boron nitride sintered body at 40 to 150° C. (CTE1) and a linear thermal expansion coefficient of the metal circuit at 40 to 150° C. (CTE2) (CTE1/CTE2) is 0.5 to 2.0.
    Type: Grant
    Filed: August 12, 2014
    Date of Patent: December 6, 2016
    Assignee: Denka Company Limited
    Inventors: Hideki Hirotsuru, Shuhei Nonaka, Toshikatsu Mitsunaga, Koki Ikarashi, Kouji Miyata, Taiki Nishi, Saori Inoue, Fumiya Kobayashi
  • Publication number: 20160227644
    Abstract: A boron nitride/resin composite circuit board having high heat dissipation characteristics and high relyability is provided. A boron nitride/resin composite circuit board, including: a plate-shaped resin-impregnated boron nitride sintered body having a plate thickness of 0.2 to 1.5 mm, the plate-shaped resin-impregnated boron nitride sintered body including 30 to 85 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally, the boron nitride particles having an average long diameter of 5 to 50 ?m, and 70 to 15 volume % of a resin; and a metal circuit adhered onto both principal planes of the plate-shaped resin-impregnated boron nitride sintered body, the metal circuit being copper or aluminum, wherein: a ratio of a linear thermal expansion coefficient in a plane direction of the resin-impregnated boron nitride sintered body at 40 to 150° C. (CTE1) and a linear thermal expansion coefficient of the metal circuit at 40 to 150° C. (CTE2) (CTE1/CTE2) is 0.5 to 2.0.
    Type: Application
    Filed: August 12, 2014
    Publication date: August 4, 2016
    Applicant: Denka Company Limited
    Inventors: Hideki HIROTSURU, Shuhei NONAKA, Toshikatsu MITSUNAGA, Koki IKARASHI, Kouji MIYATA, Taiki NISHI, Saori INOUE, Fumiya KOBAYASHI
  • Publication number: 20160130187
    Abstract: A resin-impregnated boron nitride sintered body having superior thermal conductivity and superior strength, and a resin-impregnated boron nitride sintered body having superior conductivity and small anisotropy of thermal conductivity are provided. A resin-impregnated boron nitride sintered body, including: 30 to 90 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally; and 10 to 70 volume % of a resin; wherein the boron nitride sintered body has a porosity of 10 to 70%; the boron nitride particles of the boron nitride sintered body has an average long diameter of 10 ?m or more; the boron nitride sintered body has a graphitization index by powder X-ray diffractometry is 4.0 or less; and an orientation degree of the boron nitride particles of the boron nitride sintered body by I.O.P is 0.01 to 0.
    Type: Application
    Filed: June 2, 2014
    Publication date: May 12, 2016
    Applicant: Denka Company Limited
    Inventors: Koki Ikarashi, Shuhei Nonaka, Toshikatsu Mitsunaga, Hideki Hirotsuru, Mitsuru Shiiba
  • Publication number: 20160060112
    Abstract: Provided is a boron-nitride powder that is suitable for use in a resin composition for transmitting heat from a heat-producing electronic component such as a power device to a heat-dissipating member. The boron-nitride powder reduces thermal-conductivity anisotropy and thermal contact resistance, resulting in high thermal conductivity, and contains boron-nitride particles each consisting of hexagonal boron-nitride primary particles joined together. The boron-nitride powder, which is an aggregate of said boron-nitride particles, exhibits a mean sphericity of at least 0.70, a mean particle diameter of 20-100 ?m, a porosity of 50-80%, a mean pore diameter of 0.10-2.0 ?m, a maximum pore diameter of at most 10 ?m, and a calcium content of 500-5,000 ppm. Under X-ray powder diffraction, the graphitization index of the boron-nitride powder is preferably between 1.6 and 4.0, inclusive, and the peak intensity ratio (I(002)/I(100)) between the (002) plane and the (100) plane is preferably at most 9.0.
    Type: Application
    Filed: March 7, 2014
    Publication date: March 3, 2016
    Inventors: Taiki NISHI, Koki IKARASHI, Toshikatsu MITSUNAGA
  • Publication number: 20100027261
    Abstract: To provide an LED light source unit which is excellent in heat dissipation performance, able to prevent damage to LED and bright, and which has a long life. An LED light source unit comprising a printed board, at least one light emitting diode provided on the printed board, and an adhesive tape for fixing the printed board on the surface of a heat dissipating member, wherein the thermal conductivity of the adhesive tape is from 1 to 4 W/mK, and the withstand voltage between a rear side conductor circuit and a metal housing is at least 1.0 kV.
    Type: Application
    Filed: July 20, 2007
    Publication date: February 4, 2010
    Applicant: Denki Kagaku Kogyo Kabushiki Kaisha
    Inventors: Katsunori Yashima, Takeshi Miyakawa, Kenji Miyata, Taiki Nishi, Yoshihiko Okajima, Takuya Okada, Keiji Takano, Toshikatsu Mitsunaga
  • Publication number: 20090279300
    Abstract: To provide an LED light source unit which is excellent in heat dissipation performance, able to prevent damage to LED and bright, and which has a long life. An LED light source unit comprising a printed board, at least one light emitting diode provided on the printed board, and an adhesive tape for fixing the printed board on the surface of a heat dissipating member, wherein the thermal conductivity of the adhesive tape is from 1 to 4 W/mK, and the withstand voltage between the fixing face of the printed board and the fixing face of the heat dissipating member is at least 1.0 kV.
    Type: Application
    Filed: May 31, 2007
    Publication date: November 12, 2009
    Applicant: Denki Kagaku Kogyo Kabushiki Kaisha
    Inventors: Yoshihiko Okajima, Katsunori Yashima, Toshikatsu Mitsunaga, Takuya Okada
  • Patent number: 6403697
    Abstract: Carbon black having boron solid-solubilized therein, which has an electrical resistivity of not higher than 0.1 &OHgr;cm, as measured in accordance with JIS K1469.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: June 11, 2002
    Assignee: Denki Kagaku Kogyo Kabushiki Kaisha
    Inventors: Toshikatsu Mitsunaga, Yoshiteru Yamasaki, Hiroyuki Hara, Kazuyoshi Tsuruta