Patents by Inventor Kazumichi HIROI

Kazumichi HIROI 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: 11756736
    Abstract: A manufacturing method of ceramic powder includes mixing a barium carbonate having a specific surface are of 15 m2/g or more, a titanium dioxide having a specific surface area of 20 m2/g or more, a first compound of a donor element having a larger valence than Ti, and a second compound of an acceptor element having a smaller valence than Ti and having a larger ion radium than Ti and the donor element, and synthesizing barium titanate powder by calcining the barium carbonate, the titanium dioxide, the first compound and the second compound until a specific surface area of the barium titanate powder becomes 4 m2/g or more and 25 m2/g or less.
    Type: Grant
    Filed: October 14, 2021
    Date of Patent: September 12, 2023
    Assignee: TAIYO YUDEN CO., LTD.
    Inventors: Chie Kawamura, Kazumichi Hiroi, Osamu Hattori
  • Publication number: 20230282423
    Abstract: A multilayer ceramic electronic component includes a ceramic body, which includes an electrode-stacking portion in which internal electrodes are stacked, and cover portions facing each other in a first axis direction across the electrode-stacking portion, and external electrodes each including a covering portion that covers the ceramic body from a second axis direction, and an extending portion that extends over the cover portions along the second axis direction. The ceramic body includes crystal grains of ceramic and segregated small grains located between the crystal grains. In a cross section of an end section located between the extending portion of the cover portion and the electrode-stacking portion, the number of the segregated small grains having a grain size of 0.5% or greater and 10% or less of an average grain size of the crystal grains is 40% or greater and 95% or less of the number of the crystal grains.
    Type: Application
    Filed: March 1, 2023
    Publication date: September 7, 2023
    Applicant: TAIYO YUDEN CO., LTD.
    Inventors: Norihiro ARAI, Kazumichi HIROI, Hirokazu SHIMIZU
  • Publication number: 20230081197
    Abstract: A ceramic electronic device includes a multilayer structure in which a plurality of dielectric layers and a plurality of internal electrode layers are alternately stacked. Each of the plurality of dielectric layers includes ceramic grains of a main component thereof expressed by (Ba1?x?yCaxSry)(Ti1?zZrz)O3 (0<x?0.2, 0?y?0.1, 0?z?0.1). D3<D1<D2 is satisfied when an average grain diameter of the ceramic grains of the main component of the plurality of dielectric layers in a section in which each two internal electrode layers is D1, an average grain diameter of the ceramic grains of the main component of first dielectric layers which are located at different height positions from the internal electrode layers is D2, an average grain diameter of the ceramic grains of the main component of second dielectric layers which are located at same height positions of the internal electrode layers is D3.
    Type: Application
    Filed: August 8, 2022
    Publication date: March 16, 2023
    Applicant: TAIYO YUDEN CO., LTD.
    Inventors: Yasuyuki INOMATA, Kazumichi HIROI
  • Publication number: 20220037088
    Abstract: A manufacturing method of ceramic powder includes mixing a barium carbonate having a specific surface are of 15 m2/g or more, a titanium dioxide having a specific surface area of 20 m2/g or more, a first compound of a donor element having a larger valence than Ti, and a second compound of an acceptor element having a smaller valence than Ti and having a larger ion radium than Ti and the donor element, and synthesizing barium titanate powder by calcining the barium carbonate, the titanium dioxide, the first compound and the second compound until a specific surface area of the barium titanate powder becomes 4 m2/g or more and 25 m2/g or less.
    Type: Application
    Filed: October 14, 2021
    Publication date: February 3, 2022
    Inventors: Chie KAWAMURA, Kazumichi HIROI, Osamu HATTORI
  • Patent number: 11177073
    Abstract: A manufacturing method of ceramic powder includes: synthesizing barium titanate powder from barium carbonate, titanium dioxide, manganese carbonate, and one of ammonium molybdate and tungsten oxide, wherein: a solid solution amount of the donor element is 0.05 mol or more and 0.3 mol or less; a solid solution amount of the accepter element with respect to the barium titanate is 0.02 mol or more and 0.2 mol or less on a presumption that the amount of the barium titanate is 100 mol and the acceptor element is converted into an oxide; and relationships y??0.0003x+1.0106, y??0.0002x+1.0114, 4?x?25 and y?1.0099 are satisfied when a specific surface area of the ceramic powder is “x” and an axial ratio c/a of the ceramic powder is “y”.
    Type: Grant
    Filed: May 22, 2020
    Date of Patent: November 16, 2021
    Assignee: TAIYO YUDEN CO., LTD.
    Inventors: Chie Kawamura, Kazumichi Hiroi, Osamu Hattori
  • Publication number: 20200286684
    Abstract: A manufacturing method of ceramic powder includes: synthesizing barium titanate powder from barium carbonate, titanium dioxide, manganese carbonate, and one of ammonium molybdate and tungsten oxide, wherein: a solid solution amount of the donor element is 0.05 mol or more and 0.3 mol or less; a solid solution amount of the accepter element with respect to the barium titanate is 0.02 mol or more and 0.2 mol or less on a presumption that the amount of the barium titanate is 100 mol and the acceptor element is converted into an oxide; and relationships y??0.0003x+1.0106, y??0.0002x+1.0114, 4?x?25 and y?1.0099 are satisfied when a specific surface area of the ceramic powder is “x” and an axial ratio c/a of the ceramic powder is “y”.
    Type: Application
    Filed: May 22, 2020
    Publication date: September 10, 2020
    Inventors: Chie KAWAMURA, Kazumichi HIROI, Osamu HATTORI
  • Publication number: 20190043668
    Abstract: Ceramic powder includes: barium titanate as a main component, wherein: a donor element having a larger valence than Ti is solid-solved in the barium titanate; an acceptor element having a smaller valence than Ti and larger ion radius than Ti and the donor element is solid-solved in the barium titanate, a solid solution amount of the donor element with respect to the barium titanate is 0.05 mol or more and 0.3 mol or less; a solid solution amount of the accepter element with respect to the barium titanate is 0.02 mol or more and 0.2 mol or less; and relationships y??0.0003x+1.0106, y??0.0002x+1.0114, 4?x?25 and y?1.0099 are satisfied when a specific surface area of the ceramic powder is “x” and an axial ratio c/a of the ceramic powder is “y”.
    Type: Application
    Filed: October 9, 2018
    Publication date: February 7, 2019
    Inventors: Chie KAWAMURA, Kazumichi HIROI, Osamu HATTORI
  • Patent number: 9919970
    Abstract: Dielectric layers are prepared using a dielectric material that contains a ceramic powder having Ba, Ti, and additive element X which is solid-solubilized and is at least one element selected from the group consisting of Mo, Ta, Nb, and W, wherein the standard deviation of the ratio of the peak intensity of the additive element X (XK?) measured by STEM-EDX, and the sum of the peak intensity of the Ti and peak intensity of the Ba (BaL?+TiK?) measured by STEM-EDX, is less than 10.5% of the average ratio as measured at a total of five points including the three points that divide the maximum diameter of one grain of the ceramic powder into four equal parts, and two excluding the center point of the three points that divide the diameter crossing at right angles with the maximum diameter at its center point, into four equal parts.
    Type: Grant
    Filed: November 29, 2016
    Date of Patent: March 20, 2018
    Assignee: TAIYO YUDEN CO., LTD.
    Inventors: Kunihiko Nagaoka, Kazumichi Hiroi, Minoru Ryu, Chie Kawamura
  • Publication number: 20170372841
    Abstract: A multilayer ceramic capacitor includes: a multilayer structure in which ceramic dielectric layers and internal electrode layers are alternately stacked, wherein: a main component of the ceramic dielectric layer is barium titanate in which a donor element having a larger valence than Ti is solid-solved and an acceptor element having a smaller valence than Ti and larger ion radius than Ti and the donor element is solid-solved; a solid-solution amount of the donor element is 0.05 mol or more and 0.3 mol or less on a presumption that an amount of the barium titanate is 100 mol and the donor element is converted into an oxide; and a solid solution amount of the accepter element is 0.02 mol or more and 0.2 mol or less on a presumption that the amount of the barium titanate is 100 mol and the acceptor element is converted into an oxide.
    Type: Application
    Filed: June 14, 2017
    Publication date: December 28, 2017
    Inventors: Chie KAWAMURA, Kazumichi HIROI, Osamu HATTORI
  • Publication number: 20170152187
    Abstract: Dielectric layers are prepared using a dielectric material that contains a ceramic powder having Ba, Ti, and additive element X which is solid-solubilized and is at least one element selected from the group consisting of Mo, Ta, Nb, and W, wherein the standard deviation of the ratio of the peak intensity of the additive element X (XK?) measured by STEM-EDX, and the sum of the peak intensity of the Ti and peak intensity of the Ba (BaL?+TiK?) measured by STEM-EDX, is less than 10.5% of the average ratio as measured at a total of five points including the three points that divide the maximum diameter of one grain of the ceramic powder into four equal parts, and two excluding the center point of the three points that divide the diameter crossing at right angles with the maximum diameter at its center point, into four equal parts.
    Type: Application
    Filed: November 29, 2016
    Publication date: June 1, 2017
    Inventors: Kunihiko NAGAOKA, Kazumichi HIROI, Minoru RYU, Chie KAWAMURA
  • Patent number: 9666371
    Abstract: A multilayer ceramic capacitor has a laminate comprising dielectric layers stacked alternately with internal electrode layers of different polarities, wherein: the dielectric layers contain ceramic grains whose primary component is BaTiO3; the ceramic grains contain at least one type of donor element (D) selected from the group that includes Nb, Mo, Ta, and W, and at least one type of acceptor element (A) selected from the group that includes Mg and Mn; and the ratio of the concentration of the donor element (D) and that of the acceptor element (A) (D/A) is greater than 1 at the center parts of the ceramic grains, while the D/A ratio is less than 1 at the outer edge parts of the ceramic grains (if A=0, then D/A=? and D=A=0 never occurs).
    Type: Grant
    Filed: January 20, 2016
    Date of Patent: May 30, 2017
    Assignee: TAIYO YUDEN CO., LTD.
    Inventors: Koichiro Morita, Chie Kawamura, Minoru Ryu, Katsuya Taniguchi, Kazumichi Hiroi, Yoshiki Iwazaki
  • Publication number: 20160217924
    Abstract: A multilayer ceramic capacitor has a laminate comprising dielectric layers stacked alternately with internal electrode layers of different polarities, wherein: the dielectric layers contain ceramic grains whose primary component is BaTiO3; the ceramic grains contain at least one type of donor element (D) selected from the group that includes Nb, Mo, Ta, and W, and at least one type of acceptor element (A) selected from the group that includes Mg and Mn; and the ratio of the concentration of the donor element (D) and that of the acceptor element (A) (D/A) is greater than 1 at the center parts of the ceramic grains, while the D/A ratio is less than 1 at the outer edge parts of the ceramic grains (if A=0, then D/A=? and D=A=0 never occurs).
    Type: Application
    Filed: January 20, 2016
    Publication date: July 28, 2016
    Inventors: Koichiro Morita, Chie Kawamura, Minoru Ryu, Katsuya Taniguchi, Kazumichi Hiroi, Yoshiki Iwazaki
  • Patent number: 9117590
    Abstract: A laminated ceramic electronic component has electrode layers stacked with ceramic layers, where the thickness of each electrode layer is controlled to 0.5 ?m or less and the average size of crystal grains constituting the electrode layer is controlled to 0.1 ?m or less. The occurrence of structural defects in the laminated ceramic electronic component can be suppressed and high continuity of the electrode layers stacked with the ceramic layers is ensured.
    Type: Grant
    Filed: June 19, 2013
    Date of Patent: August 25, 2015
    Assignee: TAIYO YUDEN CO., LTD.
    Inventors: Yukihiro Konishi, Yusuke Kowase, Kazumichi Hiroi, Kotaro Mizuno, Ayumu Sato
  • Patent number: 8946104
    Abstract: A dielectric ceramic whose primary component is an ABO3 compound (A contains Ba and B contains Ti) has a per-layer thickness of approx. 0.5 ?m or less, where the volume ratio to all dielectric sintered grains of those whose grain size is in a range of 0.02 ?m to 0.15 ?m is adjusted to a grain size distribution of 1% to 10%. High dielectric constant and high reliability can be achieved at the same time with the dielectric ceramic.
    Type: Grant
    Filed: June 19, 2013
    Date of Patent: February 3, 2015
    Assignee: Taiyo Yuden Co., Ltd.
    Inventors: Yukihiro Konishi, Yusuke Kowase, Kazumichi Hiroi, Kotaro Mizuno, Ayumu Sato
  • Publication number: 20130342956
    Abstract: A laminated ceramic electronic component has electrode layers stacked with ceramic layers, where the thickness of each electrode layer is controlled to 0.5 ?m or less and the average size of crystal grains constituting the electrode layer is controlled to 0.1 ?m or less. The occurrence of structural defects in the laminated ceramic electronic component can be suppressed and high continuity of the electrode layers stacked with the ceramic layers is ensured.
    Type: Application
    Filed: June 19, 2013
    Publication date: December 26, 2013
    Inventors: Yukihiro KONISHI, Yusuke KOWASE, Kazumichi HIROI, Kotaro MIZUNO, Ayumu SATO
  • Publication number: 20130342957
    Abstract: A dielectric ceramic whose primary component is an ABO3 compound (A contains Ba and B contains Ti) has a per-layer thickness of approx. 0.5 ?m or less, where the volume ratio to all dielectric sintered grains of those whose grain size is in a range of 0.02 ?m to 0.15 ?m is adjusted to a grain size distribution of 1% to 10%. High dielectric constant and high reliability can be achieved at the same time with the dielectric ceramic.
    Type: Application
    Filed: June 19, 2013
    Publication date: December 26, 2013
    Inventors: Yukihiro KONISHI, Yusuke KOWASE, Kazumichi HIROI, Kotaro MIZUNO, Ayumu SATO