Patents by Inventor Tomomi Koga

Tomomi Koga 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: 10037851
    Abstract: A multilayer ceramic capacitor includes a laminated body including an inner layer portion including ceramic dielectric layers and internal electrodes, and outer layer portions including ceramic dielectric layers. External electrodes connected to the internal electrodes are provided on both ends of the laminated body. The main constituent of the inner layer portion is a perovskite-type compound represented by ABO3. The outer layer portions include first outer layers and second outer layers respectively containing oxides that differ from each other in main constituents, and boundary reaction layers are provided between the first outer layers and the second outer layers. First ceramic dielectric layers outside the boundary reaction layers differ in color from second ceramic dielectric layers inside the boundary reaction layers.
    Type: Grant
    Filed: January 20, 2017
    Date of Patent: July 31, 2018
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Hiroyuki Wada, Kohei Shimada, Kenji Takagi, Tomomi Koga, Tomotaka Hirata, Hitoshi Nishimura, Hiroki Awata, Sui Uno
  • Publication number: 20170133156
    Abstract: A multilayer ceramic capacitor includes a laminated body including an inner layer portion including ceramic dielectric layers and internal electrodes, and outer layer portions including ceramic dielectric layers. External electrodes connected to the internal electrodes are provided on both ends of the laminated body. The main constituent of the inner layer portion is a perovskite-type compound represented by ABO3. The outer layer portions include first outer layers and second outer layers respectively containing oxides that differ from each other in main constituents, and boundary reaction layers are provided between the first outer layers and the second outer layers. First ceramic dielectric layers outside the boundary reaction layers differ in color from second ceramic dielectric layers inside the boundary reaction layers.
    Type: Application
    Filed: January 20, 2017
    Publication date: May 11, 2017
    Inventors: Hiroyuki WADA, Kohei SHIMADA, Kenji TAKAGI, Tomomi KOGA, Tomotaka HIRATA, Hitoshi NISHIMURA, Hiroki AWATA, Sui UNO
  • Patent number: 9589729
    Abstract: A multilayer ceramic capacitor includes a laminated body including an inner layer portion including ceramic dielectric layers and internal electrodes, and outer layer portions including ceramic dielectric layers. External electrodes connected to the internal electrodes are provided on both ends of the laminated body. The main constituent of the inner layer portion is a perovskite-type compound represented by ABO3. The outer layer portions include first outer layers and second outer layers respectively containing oxides that differ from each other in main constituents, and boundary reaction layers are provided between the first outer layers and the second outer layers. First ceramic dielectric layers outside the boundary reaction layers differ in color from second ceramic dielectric layers inside the boundary reaction layers.
    Type: Grant
    Filed: September 16, 2015
    Date of Patent: March 7, 2017
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hiroyuki Wada, Kohei Shimada, Kenji Takagi, Tomomi Koga, Tomotaka Hirata, Hitoshi Nishimura, Hiroki Awata, Sui Uno
  • Patent number: 9460852
    Abstract: A laminated ceramic capacitor having a laminated body composed of a plurality of ceramic layers for inner layers; a plurality of internal electrodes at the interfaces between the plurality of ceramic layers for inner layers; and a plurality of ceramic layers for outer layers, provided on the top and bottom so as to sandwich the plurality of ceramic layers for inner layers. The ceramic layers for inner layers are composed of a material containing a multiple oxide including an alkaline-earth metal. The ceramic layers for outer layers respectively have TiO2 ceramic layers containing TiO2 as their main constituent for certain layers including the outermost layers, and multiple oxide ceramic layers containing a multiple oxide including an alkaline-earth metal for the other layers.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: October 4, 2016
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Hiroyuki Wada, Kohei Shimada, Kenji Takagi, Tomomi Koga, Tomotaka Hirata, Hitoshi Nishimura, Hiroki Awata, Sui Uno
  • Patent number: 9236187
    Abstract: A multilayer ceramic capacitor includes a ceramic main body including an inner layer portion including third ceramic layers and a plurality of inner electrodes arranged at interfaces between the third ceramic layers, and first and second outer layer portions respectively including first and second ceramic layers, the first and second ceramic layers being arranged vertically so as to sandwich the inner layer portion. The third ceramic layers and the first and second outer layer portions contain a perovskite-type compound represented by ABO3 where A contains one or more of Ba, Sr, and Ca, B contains one or more of Ti, Zr, and Hf, and O represents oxygen) as a main component. Where a rare-earth element concentration (CR) in the third ceramic layers is compared to a rare-earth element concentration (Cr) in outermost layer portions including at least outermost surfaces of the first and second outer layer portions, CR>Cr (inclusive of Cr=0).
    Type: Grant
    Filed: February 13, 2015
    Date of Patent: January 12, 2016
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hiroyuki Wada, Kohei Shimada, Kenji Takagi, Tomomi Koga, Tomotaka Hirata, Hitoshi Nishimura, Hiroki Awata, Sui Uno
  • Publication number: 20160005543
    Abstract: A multilayer ceramic capacitor includes a laminated body including an inner layer portion including ceramic dielectric layers and internal electrodes, and outer layer portions including ceramic dielectric layers. External electrodes connected to the internal electrodes are provided on both ends of the laminated body. The main constituent of the inner layer portion is a perovskite-type compound represented by ABO3. The outer layer portions include first outer layers and second outer layers respectively containing oxides that differ from each other in main constituents, and boundary reaction layers are provided between the first outer layers and the second outer layers. First ceramic dielectric layers outside the boundary reaction layers differ in color from second ceramic dielectric layers inside the boundary reaction layers.
    Type: Application
    Filed: September 16, 2015
    Publication date: January 7, 2016
    Inventors: Hiroyuki WADA, Kohei SHIMADA, Kenji TAKAGI, Tomomi KOGA, Tomotaka HIRATA, Hitoshi NISHIMURA, Hiroki AWATA, Sui UNO
  • Publication number: 20150162133
    Abstract: A multilayer ceramic capacitor includes a ceramic main body including an inner layer portion including third ceramic layers and a plurality of inner electrodes arranged at interfaces between the third ceramic layers, and first and second outer layer portions respectively including first and second ceramic layers, the first and second ceramic layers being arranged vertically so as to sandwich the inner layer portion. The third ceramic layers and the first and second outer layer portions contain a perovskite-type compound represented by ABO3 where A contains one or more of Ba, Sr, and Ca, B contains one or more of Ti, Zr, and Hf, and O represents oxygen) as a main component. Where a rare-earth element concentration (CR) in the third ceramic layers is compared to a rare-earth element concentration (Cr) in outermost layer portions including at least outermost surfaces of the first and second outer layer portions, CR>Cr (inclusive of Cr=0).
    Type: Application
    Filed: February 13, 2015
    Publication date: June 11, 2015
    Inventors: Hiroyuki WADA, Kohei SHIMADA, Kenji TAKAGI, Tomomi KOGA, Tomotaka HIRATA, Hitoshi NISHIMURA, Hiroki AWATA, Sui UNO
  • Patent number: 9042082
    Abstract: A multilayer ceramic capacitor includes a ceramic main body including an inner layer portion including third ceramic layers and a plurality of inner electrodes arranged at interfaces between the third ceramic layers, and first and second outer layer portions respectively including first and second ceramic layers, the first and second ceramic layers being arranged vertically so as to sandwich the inner layer portion. The third ceramic layers and the first and second outer layer portions contain a perovskite-type compound represented by ABO3 where A contains one or more of Ba, Sr, and Ca, B contains one or more of Ti, Zr, and Hf, and O represents oxygen) as a main component. Where a rare-earth element concentration (CR) in the third ceramic layers is compared to a rare-earth element concentration (Cr) in outermost layer portions including at least outermost surfaces of the first and second outer layer portions, CR>Cr (inclusive of Cr=0).
    Type: Grant
    Filed: October 30, 2014
    Date of Patent: May 26, 2015
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hiroyuki Wada, Kohei Shimada, Kenji Takagi, Tomomi Koga, Tomotaka Hirata, Hitoshi Nishimura, Hiroki Awata, Sui Uno
  • Publication number: 20150049413
    Abstract: A multilayer ceramic capacitor includes a ceramic main body including an inner layer portion including third ceramic layers and a plurality of inner electrodes arranged at interfaces between the third ceramic layers, and first and second outer layer portions respectively including first and second ceramic layers, the first and second ceramic layers being arranged vertically so as to sandwich the inner layer portion. The third ceramic layers and the first and second outer layer portions contain a perovskite-type compound represented by ABO3 where A contains one or more of Ba, Sr, and Ca, B contains one or more of Ti, Zr, and Hf, and O represents oxygen) as a main component. Where a rare-earth element concentration (CR) in the third ceramic layers is compared to a rare-earth element concentration (Cr) in outermost layer portions including at least outermost surfaces of the first and second outer layer portions, CR>Cr (inclusive of Cr=0).
    Type: Application
    Filed: October 30, 2014
    Publication date: February 19, 2015
    Inventors: Hiroyuki WADA, Kohei SHIMADA, Kenji TAKAGI, Tomomi KOGA, Tomotaka HIRATA, Hitoshi NISHIMURA, Hiroki AWATA, Sui UNO
  • Patent number: 8841225
    Abstract: A dielectric ceramic that includes a sintered body of BaTiO3 based ceramic grains, in which the ceramic grains each include a shell part as a surface layer part and a core part inside the shell part. The ceramic grains contain, as accessory constituents, R (R, which is a rare-earth element, is at least one selected from the group consisting of Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, and Y) and M (M is at least one selected from the group consisting of Mg, Mn, Ni, Co, Fe, Cr, Cu, Al, Mo, W, and V). R and M are present in the shell part of the ceramic grain, and concentrations of R and M contained in the shell part are increased from a grain boundary toward the core part.
    Type: Grant
    Filed: October 2, 2012
    Date of Patent: September 23, 2014
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tomomi Koga, Koichi Banno
  • Patent number: 8213153
    Abstract: A dielectric ceramic with stable insulation properties even after calcination under a reducing atmosphere, as is preferred for a laminated ceramic capacitor, is a CaTiO3 composition containing Sn. It is preferable for the dielectric ceramic to contain, as its main component, (Ca1-xBaxSny)TiO3 (0?x<0.2, 0.01?y<0.2) with a solution of Sn at the B site.
    Type: Grant
    Filed: January 28, 2010
    Date of Patent: July 3, 2012
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Megumi Morita, Shoichiro Suzuki, Toshikazu Takeda, Tomomi Koga
  • Publication number: 20100195266
    Abstract: A dielectric ceramic with stable insulation properties even after calcination under a reducing atmosphere, as is preferred for a laminated ceramic capacitor, is a CaTiO3 composition containing Sn. It is preferable for the dielectric ceramic to contain, as its main component, (Ca1-xBaxSny)TiO3 (0?x<0.2, 0.01?y<0.2) with a solution of Sn at the B site.
    Type: Application
    Filed: January 28, 2010
    Publication date: August 5, 2010
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Megumi MORITA, Shoichiro Suzuki, Toshikazu Takeda, Tomomi Koga
  • Publication number: 20090244805
    Abstract: Provided is a dielectric ceramic in which, while achieving a dielectric constant ? of 500 or more, a breakdown voltage higher than 90 kV/mm can be obtained and which is suitable for constituting dielectric ceramic layers of a multilayer ceramic capacitor for medium-to-high voltage application. As the dielectric ceramic constituting dielectric ceramic layers of the multilayer ceramic capacitor, a dielectric ceramic including, as a main component, (Ba1-xCax)mTiO3 where 0.30?x?0.50, and 0.950?m?1.025 is used. Preferably, the dielectric ceramic further includes a rare-earth element in an amount of 1 to 14 parts by mole relative to 100 parts by mole of the main component, and further includes Mn, Mg, and Si, respectively, in amounts of 0.1 to 3.0 parts by mole, 0.5 to 5.0 parts by mole, and 1.0 to 5.0 parts by mole relative to 100 parts by mole of the main component.
    Type: Application
    Filed: June 15, 2009
    Publication date: October 1, 2009
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Koichi Banno, Tomomi Koga