Patents by Inventor Dan Sakurai

Dan Sakurai 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: 11955283
    Abstract: A dielectric ceramic composition includes a barium titanate, an oxide of an R element, an oxide of an M element, and an oxide containing Si. The R element is one or more elements selected from Eu, Gd, Tb, Dy, Y, Ho, and Yb. The M element is one or more elements selected from Mg, Ca, Mn, V, and Cr. A ratio of an amount of the oxide of the R element in terms of R2O3 to an amount of the oxide containing Si in terms of SiO2 is 0.8:1 to 2.2:1. A ratio of an amount of the oxide of the M element in terms of MO to the amount of the oxide containing Si in terms of SiO2 is 0.2:1 to 1.8:1.50% or more of the number of dielectric particles constituting the dielectric ceramic composition is core-shell dielectric particles having a core-shell structure.
    Type: Grant
    Filed: March 8, 2021
    Date of Patent: April 9, 2024
    Assignee: TDK CORPORATION
    Inventors: Taku Murakami, Nobuto Morigasaki, Dan Sakurai, Takuma Ariizumi, Toshihiko Kaneko
  • Patent number: 11639313
    Abstract: A dielectric ceramic composition contains dielectric particles containing a main component represented by a composition formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3 and grain boundaries present between the dielectric particles. The values of m, x, y, and z in the composition formula are all molar ratios. In the composition formula, 0.9?m?1.4, 0?x<1.0, 0<y?1.0, 0.9?(x+y)?1.0, and 0.9?z?1.0 are satisfied. The dielectric particles contain specific structural particles having a predetermined intragranular structure, and each of the specific structural particles intragranularly includes a first region and a second region having different Ca concentrations from each other. C2/C1 is less than 0.8 in which C1 is an average value of the Ca concentration in the first region and C2 is an average value of the Ca concentration in the second region.
    Type: Grant
    Filed: December 15, 2021
    Date of Patent: May 2, 2023
    Assignee: TDK CORPORATION
    Inventors: Dan Sakurai, Yasuhiro Ito, Nobuto Morigasaki, Toshihiko Kaneko, Toshihiro Iguchi
  • Publication number: 20220194859
    Abstract: A dielectric ceramic composition contains dielectric particles containing a main component represented by a composition formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3 and grain boundaries present between the dielectric particles. The values of m, x, y, and z in the composition formula are all molar ratios. In the composition formula, 0.9?m?1.4, 0?x<1.0, 0<y?1.0, 0.9?(x+y)?1.0, and 0.9?z?1.0 are satisfied. The dielectric particles contain specific structural particles having a predetermined intragranular structure, and each of the specific structural particles intragranularly includes a first region and a second region having different Ca concentrations from each other. C2/C1 is less than 0.8 in which C1 is an average value of the Ca concentration in the first region and C2 is an average value of the Ca concentration in the second region.
    Type: Application
    Filed: December 15, 2021
    Publication date: June 23, 2022
    Applicant: TDK CORPORATION
    Inventors: Dan SAKURAI, Yasuhiro ITO, Nobuto MORIGASAKI, Toshihiko KANEKO, Toshihiro IGUCHI
  • Publication number: 20210304966
    Abstract: A dielectric ceramic composition includes a barium titanate, an oxide of an R element, an oxide of an M element, and an oxide containing Si. The R element is one or more elements selected from Eu, Gd, Tb, Dy, Y, Ho, and Yb. The M element is one or more elements selected from Mg, Ca, Mn, V, and Cr. A ratio of an amount of the oxide of the R element in terms of R2O3 to an amount of the oxide containing Si in terms of SiO2 is 0.8:1 to 2.2:1. A ratio of an amount of the oxide of the M element in terms of MO to the amount of the oxide containing Si in terms of SiO2 is 0.2:1 to 1.8:1.50% or more of the number of dielectric particles constituting the dielectric ceramic composition is core-shell dielectric particles having a core-shell structure.
    Type: Application
    Filed: March 8, 2021
    Publication date: September 30, 2021
    Applicant: TDK CORPORATION
    Inventors: Taku MURAKAMI, Nobuto MORIGASAKI, Dan SAKURAI, Takuma ARIIZUMI, Toshihiko KANEKO
  • Patent number: 11114247
    Abstract: The object of the present invention is to provide the multilayer ceramic capacitor having no deterioration of dielectric properties even in case an inhibitor of an internal electrode layer is pushed out to a dielectric layer when sintering. The multilayer ceramic capacitor 1 including a capacitor element body 10 comprising a dielectric layer 2 and an internal electrode layer 3 stacked in an alternating manner, wherein when Za represents Zr concentration of an dielectric particle in a center part 6 of the dielectric layer 2 and Zb represents Zr concentration of a dielectric particle near the internal electrode layer, 0<(Za/Zb)<1 is satisfied.
    Type: Grant
    Filed: January 17, 2019
    Date of Patent: September 7, 2021
    Assignee: TDK CORPORATION
    Inventors: Dan Sakurai, Toshihiko Kaneko, Nobuto Morigasaki, Toshinari Takahashi, Yasuhiro Ito
  • Patent number: 10804033
    Abstract: The object of the present invention is to provide a dielectric ceramic composition having good properties, particularly good IR property and high temperature accelerated lifetime. The dielectric ceramic composition of the present invention has a main component made of a perovskite type compound expressed by a compositional formula of (Ba1-x-ySrxCay)m(Ti1-zZrz)O3 (note that, m, x, y, and z of the above compositional formula all represent molar ratios, and each satisfies 0.9?m?1.1, 0?x?0.5, 0?y?0.3, 0?(x+y)?0.6, and 0.03?z?0.
    Type: Grant
    Filed: December 21, 2018
    Date of Patent: October 13, 2020
    Assignee: TDK CORPORATION
    Inventors: Dan Sakurai, Toshihiko Kaneko, Nobuto Morigasaki, Toshinari Takahashi, Yasuhiro Ito
  • Patent number: 10614957
    Abstract: A dielectric ceramic composition having good properties, particularly good IR property and high temperature accelerated lifetime, even under high electric field intensity. A dielectric ceramic composition having a main component made of a perovskite type compound expressed by a compositional formula of (Ba1-x-ySrxCay)m(Ti1-zZrz)O3 (note that, m, x, y, and z of the above compositional formula all represent molar ratios, and each satisfies 0.9<m<1.1, 0<x<0.5, 0<y<0.3, 0<(x+y)<0.6, and 0.03<z<0.3), and a first sub component made of an oxide of a rare earth element R (note that, R is at least one selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), wherein the dielectric ceramic composition includes dielectric particles and a particle boundary.
    Type: Grant
    Filed: January 17, 2019
    Date of Patent: April 7, 2020
    Assignee: TDK CORPORATION
    Inventors: Dan Sakurai, Toshihiko Kaneko, Nobuto Morigasaki, Toshinari Takahashi, Yasuhiro Ito
  • Publication number: 20190237264
    Abstract: The object of the present invention is to provide the multilayer ceramic capacitor having no deterioration of dielectric properties even in case an inhibitor of an internal electrode layer is pushed out to a dielectric layer when sintering. The multilayer ceramic capacitor 1 including a capacitor element body 10 comprising a dielectric layer 2 and an internal electrode layer 3 stacked in an alternating manner, wherein when Za represents Zr concentration of an dielectric particle in a center part 6 of the dielectric layer 2 and Zb represents Zr concentration of a dielectric particle near the internal electrode layer, 0<(Za/Zb)<1 is satisfied.
    Type: Application
    Filed: January 17, 2019
    Publication date: August 1, 2019
    Applicant: TDK CORPORATION
    Inventors: Dan SAKURAI, Toshihiko KANEKO, Nobuto MORIGASAKI, Toshinari TAKAHASHI, Yasuhiro ITO
  • Publication number: 20190237255
    Abstract: A dielectric ceramic composition having good properties, particularly good IR property and high temperature accelerated lifetime, even under high electric field intensity. A dielectric ceramic composition having a main component made of a perovskite type compound expressed by a compositional formula of (Ba1-x-ySrxCay)m(Ti1-zZrz)O3 (note that, m, x, y, and z of the above compositional formula all represent molar ratios, and each satisfies 0.9<m<1.1, 0<x<0.5, 0<y<0.3, 0<(x+y)<0.6, and 0.03<z<0.3), and a first sub component made of an oxide of a rare earth element R (note that, R is at least one selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), wherein the dielectric ceramic composition includes dielectric particles and a particle boundary.
    Type: Application
    Filed: January 17, 2019
    Publication date: August 1, 2019
    Applicant: TDK CORPORATION
    Inventors: Dan SAKURAI, Toshihiko KANEKO, Nobuto MORIGASAKI, Toshinari TAKAHASHI, Yasuhiro ITO
  • Publication number: 20190237254
    Abstract: The object of the present invention is to provide a dielectric ceramic composition having good properties, particularly good IR property and high temperature accelerated lifetime. The dielectric ceramic composition of the present invention has a main component made of a perovskite type compound expressed by a compositional formula of (Ba1-x-ySrxCay)m(Ti1-zZrz)O3 (note that, m, x, y, and z of the above compositional formula all represent molar ratios, and each satisfies 0.9?m?1.1, 0?x?0.5, 0?y?0.3, 0?(x+y)?0.6, and 0.03?z?0.
    Type: Application
    Filed: December 21, 2018
    Publication date: August 1, 2019
    Applicant: TDK CORPORATION
    Inventors: Dan SAKURAI, Toshihiko KANEKO, Nobuto MORIGASAKI, Toshinari TAKAHASHI, Yasuhiro ITO
  • Patent number: 10074480
    Abstract: A dielectric ceramic composition having good characteristic even under high electric field intensity, and particularly good IR characteristic and high temperature accelerated lifetime. The present invention is a dielectric ceramic composition comprising, a main component comprising a perovskite type compound shown by a compositional formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3, a first sub component comprising oxides of a rare earth element, a second sub component as a sintering agent, wherein said dielectric ceramic composition is a complete solid solution particle wherein the rare earth element is solid dissolved to entire dielectric particle, or a core-shell particle having high ratio of the diffusion phase, and comprises the dielectric particle having 5 to 20 atom % of the average concentration of the rare earth element in the diffusion phase, and having uniform concentration distribution of the rare earth element in the diffusion phase.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: September 11, 2018
    Assignee: TDK CORPORATION
    Inventors: Dan Sakurai, Nobuto Morigasaki, Tatsuya Ishii, Takuma Ariizumi, Shinsuke Hashimoto, Yasuhiro Ito
  • Patent number: 10059630
    Abstract: The object of the present invention is to provide the dielectric ceramic composition having good characteristics even under the high electric field intensity, and particularly good IR characteristic and the high temperature accelerated lifetime. The dielectric ceramic composition according to the present invention comprises a main component comprising a perovskite type compound shown by a compositional formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3 (note that, said “m”, “x”, “y” and “z” all show a mol ratio, and each satisfies 0.94?m?1.1, 0?x?0.2, 0?y?0.2, 0.06?z<0.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: August 28, 2018
    Assignee: TDK CORPORATION
    Inventors: Dan Sakurai, Nobuto Morigasaki, Tatsuya Ishii, Takuma Ariizumi
  • Patent number: 9966190
    Abstract: A dielectric ceramic composition has good characteristics even under the high electric field intensity, and particularly good IR characteristic and the high temperature accelerated lifetime. The dielectric ceramic composition has a main component having a perovskite type compound shown by a compositional formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3, a first sub component having oxides of a rare earth element R, a second sub component as a sintering agent, wherein the dielectric particles has dielectric particles having high diffusion rate of the rare earth element, preferably of a complete solid solution particle, and when a concentration of Ti atom in the diffusion phase is 100 atom %, then an average concentration of the rare earth element R in the diffusion phase is 5 atom % or more, and an average concentration of Zr in the diffusion phase is 10 atom % or more.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: May 8, 2018
    Assignee: TDK CORPORATION
    Inventors: Dan Sakurai, Nobuto Morigasaki, Tatsuya Ishii, Takuma Ariizumi, Shinsuke Hashimoto, Yasuhiro Ito
  • Publication number: 20170287635
    Abstract: A dielectric ceramic composition having good characteristic even under high electric field intensity, and particularly good IR characteristic and high temperature accelerated lifetime. The present invention is a dielectric ceramic composition comprising, a main component comprising a perovskite type compound shown by a compositional formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3, a first sub component comprising oxides of a rare earth element, a second sub component as a sintering agent, wherein said dielectric ceramic composition is a complete solid solution particle wherein the rare earth element is solid dissolved to entire dielectric particle, or a core-shell particle having high ratio of the diffusion phase, and comprises the dielectric particle having 5 to 20 atom % of the average concentration of the rare earth element in the diffusion phase, and having uniform concentration distribution of the rare earth element in the diffusion phase.
    Type: Application
    Filed: March 22, 2017
    Publication date: October 5, 2017
    Applicant: TDK CORPORATION
    Inventors: Dan SAKURAI, Nobuto MORIGASAKI, Tatsuya ISHII, Takuma ARIIZUMI, Shinsuke HASHIMOTO, Yasuhiro ITO
  • Publication number: 20170287636
    Abstract: A dielectric ceramic composition has good characteristics even under the high electric field intensity, and particularly good IR characteristic and the high temperature accelerated lifetime. The dielectric ceramic composition has a main component having a perovskite type compound shown by a compositional formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3, a first sub component having oxides of a rare earth element R, a second sub component as a sintering agent, wherein the dielectric particles has dielectric particles having high diffusion rate of the rare earth element, preferably of a complete solid solution particle, and when a concentration of Ti atom in the diffusion phase is 100 atom %, then an average concentration of the rare earth element R in the diffusion phase is 5 atom % or more, and an average concentration of Zr in the diffusion phase is 10 atom % or more.
    Type: Application
    Filed: March 22, 2017
    Publication date: October 5, 2017
    Applicant: TDK CORPORATION
    Inventors: Dan SAKURAI, Nobuto MORIGASAKI, Tatsuya ISHII, Takuma ARIIZUMI, Shinsuke HASHIMOTO, Yasuhiro ITO
  • Publication number: 20170283328
    Abstract: The object of the present invention is to provide the dielectric ceramic composition having good characteristics even under the high electric field intensity, and particularly good IR characteristic and the high temperature accelerated lifetime. The dielectric ceramic composition according to the present invention comprises a main component comprising a perovskite type compound shown by a compositional formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3 (note that, said “m”, “x”, “y” and “z” all show a mol ratio, and each satisfies 0.94?m?1.1, 0?x?0.2, 0?y?0.2, 0.06?z<0.
    Type: Application
    Filed: March 22, 2017
    Publication date: October 5, 2017
    Applicant: TDK CORPORATION
    Inventors: Dan SAKURAI, Nobuto MORIGASAKI, Tatsuya ISHII, Takuma ARIIZUMI
  • Patent number: 8450230
    Abstract: A dielectric ceramic composition comprises a main component composed of at least one selected from BaTiO3, (Ba, Ca)TiO3, (Ba, Sr)TiO3 and (Ba, Ca, Sr)TiO3, an oxide of rare earth element and a composite compound including Ba. 9 to 13 mol of the composite compound in terms of composite compound is included in the dielectric composition. The dielectric ceramic composition includes surface diffusion particles having surface diffusion structure composed of non diffusion phase and diffusion phase including rare earth element. In the surface diffusion particle, when an area of the non diffusion phase is defined as S1, an area of the diffusion phase is defined as S2, S1 and S2 satisfy a relation of S1:S2=20:80 to 30:70 (Note that, except S1=30 and S2=70), when an average concentration of the rare earth element in the surface diffusion particle is defined as C, S2 and C satisfy a relation of 4.8?S2×C?5.8.
    Type: Grant
    Filed: December 27, 2010
    Date of Patent: May 28, 2013
    Assignee: TDK Corporation
    Inventors: Masayuki Tamura, Satoshi Takagi, Dan Sakurai, Sanshiro Aman, Yuki Kamada
  • Patent number: 8192851
    Abstract: A dielectric ceramic composition comprises a main component including BaTiO3, a first subcomponent including BaZrO3, a second subcomponent including an oxide of Mg, a third subcomponent including an oxide of rare earth, a fourth subcomponent including an oxide of at least one element selected from Mn, Cr, Co and Fe, and a fifth subcomponent including an oxide of at least one element selected from Si, Al, Ge, B and Li. At least a part of dielectric particles constituting the dielectric ceramic composition comprises a surface diffusion structure comprised of a central layer and a diffusion layer therearound. CR and CRmax, respectively defined as a concentration of said “R” in a proximity point to a boundary face of the dielectric particle and a maximum concentration of the “R” in the diffusion layer, satisfy a relation of CRmax/CR>1.
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: June 5, 2012
    Assignee: TDK Corporation
    Inventors: Sanshiro Aman, Takashi Kojima, Mari Miyauchi, Masakazu Hosono, Dan Sakurai, Kosuke Takano, Nobuto Morigasaki
  • Publication number: 20110164346
    Abstract: A dielectric ceramic composition comprises a main component composed of at least one selected from BaTiO3, (Ba, Ca)TiO3, (Ba, Sr)TiO3 and (Ba, Ca, Sr)TiO3, an oxide of rare earth element and a composite compound including Ba. 9 to 13 mol of the composite compound in terms of composite compound is included in the dielectric composition. The dielectric ceramic composition includes surface diffusion particles having surface diffusion structure composed of non diffusion phase and diffusion phase including rare earth element. In the surface diffusion particle, when an area of the non diffusion phase is defined as S1, an area of the diffusion phase is defined as S2, S1 and S2 satisfy a relation of S1:S2=20:80 to 30:70 (Note that, except S1=30 and S2=70) , when an average concentration of the rare earth element in the surface diffusion particle is defined as C, S2 and C satisfy a relation of 4.8?S2×C?5.8.
    Type: Application
    Filed: December 27, 2010
    Publication date: July 7, 2011
    Applicant: TDK CORPORATION
    Inventors: Masayuki TAMURA, Satoshi TAKAGI, Dan SAKURAI, Sanshiro AMAN, Yuki KAMADA
  • Patent number: 7580242
    Abstract: The invention aims at providing a dielectric ceramic composition including BamTiO2+m where “m” satisfies 0.99?m?1.01 and BanZrO2+n where “n” satisfies 0.99?n?1.01, an oxide of Mg, an oxide of R where R is at least one selected from Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, an oxide of at least one element selected from Mn, Cr, Co and Fe, and an oxide of at least one element selected from Si, Li, Al, Ge and B. 35 to 65 moles of BanZrO2+n, 4 to 12 moles of an oxide of Mg, 4 to 15 moles of an oxide of R, 0.5 to 3 moles of an oxide of Mn, Cr, Co and Fe, and 3 to 9 moles of an oxide of Si, Li, Al, Ge and B are included therein per 100 moles of the BamTiO2+m.
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: August 25, 2009
    Assignee: TDK Corporation
    Inventors: Sanshiro Aman, Takashi Kojima, Mari Miyauchi, Masakazu Hosono, Dan Sakurai, Kosuke Takano, Nobuto Morigasaki