Patents Assigned to Kawatetsu Mining Co., Ltd.
  • Patent number: 8029930
    Abstract: A positive electrode material for a lithium secondary battery, which is high in safety, high in capacity, excellent in cycle performance, and high in charge/discharge efficiency, is provided. The positive electrode material for a lithium secondary battery is a powder containing a Li—Ni—Co—O or Li—Ni—Co—Ba—O system component as a main component and having an amorphous phase of an oxide mixed in each of particles or formed at the surface of the particle.
    Type: Grant
    Filed: November 17, 2003
    Date of Patent: October 4, 2011
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventors: Yoshiaki Hamano, Hidefumi Konnai
  • Patent number: 7510804
    Abstract: A cathode material for use in a lithium secondary battery of excellent thermal stability contributing to the improvement of safety of the battery and having large discharging capacity, as well as a method of manufacturing the cathode material for use in the lithium secondary battery, based on the improved method for measuring the thermal stability of the cathode material, the cathode material comprising a compound represented by the chemical formula: LixNiyCozMmO2 in which the material is powdery and the BET specific surface area is 0.8 m2/g or less, M in the chemical formula represents one or more of element selected from Ba, Sr and B, and x, y, z and m are, respectively, 0.9?x?1.1, 0.5?y?0.95, 0.05?z?0.5 and 0.0005?m?0.02.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: March 31, 2009
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventors: Yoshiaki Hamano, Hidefumi Konnai, Toshihiko Funahashi
  • Publication number: 20070193410
    Abstract: A copper alloy powder for an electrically conductive paste is provided, which is characterized in that the copper alloy powder comprises 80 to 99.9 mass % of Cu and 0.1 to 20 mass % of one or two elements selected from the group consisting of Ta and W and has an average particle size of 0.1 to 1 ?m. This copper alloy powder has a higher starting temperature for sintering, higher oxidation resistance and better heat resistance than a copper powder.
    Type: Application
    Filed: April 10, 2007
    Publication date: August 23, 2007
    Applicant: KAWATETSU MINING CO., LTD
    Inventor: Kensuke Matsuki
  • Patent number: 7244286
    Abstract: A copper alloy powder for an electrically conductive paste is provided, which is characterized in that the copper alloy powder comprises 80 to 99.9 mass % of Cu and 0.1 to 20 mass % of one or two elements selected from the group consisting of Ta and W and has an average particle size of 0.1 to 1 ?m. This copper alloy powder has a higher starting temperature for sintering, higher oxidation resistance and better heat resistance than a copper powder.
    Type: Grant
    Filed: November 28, 2002
    Date of Patent: July 17, 2007
    Assignee: Kawatetsu Mining Co., Ltd
    Inventor: Kensuke Matsuki
  • Patent number: 7175688
    Abstract: A Ni—Fe based alloy powder of the present invention contains not less than 90% by a combined mass of Ni and Fe and homogeneously has particles having an average particle diameter from 0.1 to 1 ?m, and an average value of mass ratio Fe/(Fe+Ni) from 15% to 25% both inclusive, wherein the ratio of a maximum value X and a minimum value Y of Fe/(Fe+Ni), which are found at individual points in the region ranging from the center of any particle of the alloy powder to locations apart by 0.9 fold of the particle radius therefrom, X/Y is from 1 to 2. By producing a sintered part using this Ni—Fe based alloy powder as a raw material powder, it is possible to obtain electronic circuit parts which are homogenous and have high magnetic permeability.
    Type: Grant
    Filed: December 26, 2002
    Date of Patent: February 13, 2007
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventor: Kensuke Matsuki
  • Patent number: 6982047
    Abstract: The present invention improves the oxidation resistance of an ultrafine metal powder for use in the internal electrode of a multilayer ceramic capacitance and suppresses an increase in the thickness of a metal internal electrode film resulting from the spheroidization of the molten metal under surface tension during the formation of the metal internal electrode film. The ultrafine metal powder has a sulfur-containing compound of not less than one element selected from the group consisting of Y, Zr, and La present on the surface of the particle thereof and is produced by performing an ultrafine metal powder purification step of dispersing the ultrafine metal powder in a slurry, a surface treatment step of adding an aqueous solution containing a sulfate of not less than one element selected from the group consisting of Y, Zr, and La to the slurry to form the compound on the surface of the metal particle, a filtering step, and a drying step.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: January 3, 2006
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventor: Morishige Uchida
  • Patent number: 6903645
    Abstract: This invention provides a surface mounting type planar magnetic device comprised of upper ferrite magnetic film, lower ferrite magnetic film and a planar coil interposed therebetween. For applying surface mount technology, an opening is formed in the upper ferrite magnetic film above a coil terminal portion and then, an external electrode conductive with the coil terminal portion through the opening is formed on the upper ferrite magnetic film. Further, this surface mounting type planar magnetic device is of a thin structure and can be mounted on the surface of a printed board. Its power loss is small, its inductance is large, its frequency characteristic is excellent, the disparity of the characteristic is small and its reliability is excellent.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: June 7, 2005
    Assignees: Kawatetsu Mining Co., Ltd., Kabushiki Kaisha Toshiba
    Inventors: Tetsuhiko Mizoguchi, Tetsuo Inoue, Shigeru Yatabe, Yasutaka Fukuda, Yoshihito Tachi
  • Patent number: 6881239
    Abstract: An ultrafine metal powder slurry with high dispersibility includes an organic solvent; a surfactant having a hydrophilic group and a lipophilic group; and an ultrafine metal powder in an amount more than 60% by mass and less than 95% by mass. In the slurry, the hydrophilic group of the surfactant is at least one selected from a sulfonato group, sulfo group, sulfonyldioxy group, polyoxyethylene group with carboxyl group, and polyoxyethylene group with phosphate group, and the lipophilic group is an alkyl containing 12 or more carbon atoms or an alkylphenyl. The ultrafine metal powder slurry includes no aggregated particles, exhibits good dispersibility and is useful as a metal material for conductive pastes. The slurry can save a part of process steps in conventional conductive paste production processes, can shorten a process time and can save in labor.
    Type: Grant
    Filed: December 13, 2002
    Date of Patent: April 19, 2005
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventor: Morishige Uchida
  • Patent number: 6881377
    Abstract: Provided is an ultrafine nickel powder suitable for a laminated ceramic capacitor electrode material. According to the ultrafine nickel powder, cracks and/or delamination are not liable to generate in the process for producing a ceramic capacitor, and its internal electrode can be made into a thinner layer, and the electric risistivity of the capacitor-can be made low. The ultrafine nickel powder has an average particle size of 0.1-1.0 ?m, having the sulfur content of 0.02-1.0% by weight, and particles thereof being spherical, thereby exhibiting excellent properties. They can be produced by vapor phase hydrogen-reducing process using nickel chloride vapor.
    Type: Grant
    Filed: May 21, 2003
    Date of Patent: April 19, 2005
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventors: Hideshi Katayama, Kan Saito, Shuetsu Ogasawara, Takao Hamada
  • Patent number: 6831543
    Abstract: A surface mounting type planar magnetic device comprised of upper ferrite magnetic film, lower ferrite magnetic film and a planar coil interposed therebetween. For applying surface mount technology, an opening is formed in the upper ferrite magnetic film above a coil terminal portion and then, an external electrode conductive with the coil terminal portion through the opening is formed on the upper ferrite magnetic film. Further, this surface mounting type planar magnetic device is of a thin structure and can be mounted on the surface of a printed board. Its power loss is small, its inductance is large, its frequency characteristic is excellent, the disparity of the characteristic is small and its reliability is excellent.
    Type: Grant
    Filed: February 23, 2001
    Date of Patent: December 14, 2004
    Assignees: Kawatetsu Mining Co., Ltd., Kabushiki Kaisha Toshiba
    Inventors: Tetsuhiko Mizoguchi, Tetsuo Inoue, Shigeru Yatabe, Yasutaka Fukuda, Yoshihito Tachi
  • Publication number: 20040232803
    Abstract: A piezoelectric single crystal device for actively employing the electromechanical coupling factor k31 in the direction orthogonal to the polarization direction is provided. Specifically, with the polarization direction as [001] axis of a pseudocubic system, an angle between the normal direction 1 of the piezoelectric device edge face and the direction n orthogonal to the domain structure within the crystal face including [010] and [100] axes orthogonal to the polarization direction is in the range 0 to 15° or 40 to 50°.
    Type: Application
    Filed: May 17, 2004
    Publication date: November 25, 2004
    Applicant: KAWATETSU MINING CO., LTD.
    Inventors: Mitsuyoshi Matsushita, Yousuke Iwasaki
  • Publication number: 20040175569
    Abstract: The present invention improves the oxidation resistance of an ultrafine metal powder for use in the internal electrode of a multilayer ceramic capacitance and suppresses an increase in the thickness of a metal internal electrode film resulting from the spheroidization of the molten metal under surface tension during the formation of the metal internal electrode film. The ultrafine metal powder has a sulfur-containing compound of not less than one element selected from the group consisting of Y, Zr, and La present on the surface of the particle thereof and is produced by performing an ultrafine metal powder purification step of dispersing the ultrafine metal powder in a slurry, a surface treatment step of adding an aqueous solution containing a sulfate of not less than one element selected from the group consisting of Y, Zr, and La to the slurry to form the compound on the surface of the metal particle, a filtering step, and a drying step.
    Type: Application
    Filed: November 14, 2003
    Publication date: September 9, 2004
    Applicant: KAWATETSU MINING CO., LTD.
    Inventor: Morishige Uchida
  • Publication number: 20040166370
    Abstract: This invention provides a surface mounting type planar magnetic device comprised of upper ferrite magnetic film, lower ferrite magnetic film and a planar coil interposed therebetween. For applying surface mount technology, an opening is formed in the upper ferrite magnetic film above a coil terminal portion and then, an external electrode conductive with the coil terminal portion through the opening is formed on the upper ferrite magnetic film. Further, this surface mounting type planar magnetic device is of a thin structure and can be mounted on the surface of a printed board. Its power loss is small, its inductance is large, its frequency characteristic is excellent, the disparity of the characteristic is small and its reliability is excellent.
    Type: Application
    Filed: March 4, 2004
    Publication date: August 26, 2004
    Applicants: Kawatetsu Mining Co., Ltd., Kabushiki Kaisha Toshiba
    Inventors: Tetsuhiko Mizoguchi, Tetsuo Inoue, Shigeru Yatabe, Yasutaka Fukuda, Yoshihito Tachi
  • Patent number: 6765786
    Abstract: A niobium powder is provided for producing a niobium capacitor enhanced in the thermal stability of oxide films on niobium, with less leak current and less deterioration of leak current after application of thermal loads. The niobium powder contains form 0.005 to 0.10 mass % of hydrogen and from 0.002 to 5 mass % of sulfur and, further preferably, one or both of magnesium and aluminum in an amount from 0.002 to 1 mass % in total. The specific surface area of the powder is 1 to 10 m2/g and the average particle diameter of the secondary particles is 10 to 200 &mgr;m.
    Type: Grant
    Filed: March 18, 2003
    Date of Patent: July 20, 2004
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventors: Tadasu Kirihara, Nobuyuki Sato, Osamu Ebato, Kan Saito
  • Patent number: 6756238
    Abstract: A domain controlled piezoelectnc single crystal is disclosed which uses a lateral vibration mode for an electromechanical coupling factor k31 not less than 70% and a piezoelectric constant −d31 not less than 1200 pC/N, with an electromechanical coupling factor k33 in the longitudinal vibration mode not less than 80% and a piezoelectric constant d33 not less than 800 pC/N. Also, a piezoelectric single crystal is disclosed which uses a high-performance longitudinal vibration mode with k31 not more than 30%. A fabrication method applies a DC electric field of 400 V/mm to 1500 V/mm for a maximum of two hours in a temperature range of 20° C. to 200° C. as polarization conditions in the thickness direction of the piezoelectric single crystal. The method can include cooling, or heating and cooling between temperature boundaries of rhombohedral and tetragonal crystals or between tetragonal and cubic crystals or within a cubic crystal temperature range.
    Type: Grant
    Filed: September 19, 2002
    Date of Patent: June 29, 2004
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventors: Toshio Ogawa, Mitsuyoshi Matsushita, Yoshihito Tachi
  • Publication number: 20040110066
    Abstract: A positive electrode material for a lithium secondary battery which is high in safety, high in capacity, excellent in rate performance and high temperature storage performance and high in charge/discharge efficiency is provided. The positive electrode material for a lithium secondary battery is obtained by adding Al to a Li—Ni—Co—Ba—O system raw material or preferably by adding Al and an amorphous phase of an oxide thereto.
    Type: Application
    Filed: November 17, 2003
    Publication date: June 10, 2004
    Applicant: KAWATETSU MINING CO., LTD.
    Inventors: Yoshiaki Hamano, Hidefumi Konnai
  • Publication number: 20040110065
    Abstract: A positive electrode material for a lithium secondary battery, which is high in safety, high in capacity, excellent in cycle performance, and high in charge/discharge efficiency, is provided. The positive electrode material for a lithium secondary battery is a powder containing a Li—Ni—Co—O or Li—Ni—Co—Ba—O system component as a main component and having an amorphous phase of an oxide mixed in each of particles or formed at the surface of the particle.
    Type: Application
    Filed: November 17, 2003
    Publication date: June 10, 2004
    Applicant: KAWATETSU MINING CO., LTD.
    Inventors: Yoshiaki Hamano, Hidefumi Konnai
  • Publication number: 20030196516
    Abstract: Provided is an ultrafine nickel powder suitable for a laminated ceramic capacitor electrode material. According to the ultrafine nickel powder, cracks and/or delamination are not liable to generate in the process for producing a ceramic capacitor, and its internal electrode can be made into a thinner layer, and the electric risistivity of the capacitor-can be made low. The ultrafine nickel powder has an average particle size of 0.1-1.0 &mgr;m, having the sulfur content of 0.02-1.0% by weight, and particles thereof being spherical, thereby exhibiting excellent properties. They can be produced by vapor phase hydrogen-reducing process using nickel chloride vapor.
    Type: Application
    Filed: May 21, 2003
    Publication date: October 23, 2003
    Applicant: KAWATETSU MINING CO., LTD.
    Inventors: Hideshi Katayama, Kan Saito, Shuetsu Ogasawara, Takao Hamada
  • Patent number: 6635100
    Abstract: A niobium powder for forming an anode of a solid electrolytic capacitor which improves the defects in the prior art that an average particle diameter is too small, niobium is consumed as an oxide film in anodic oxidation step and the effective electrode surface area decreases. In the improved powder, for primary particles, the average particle diameter is 0.10-2 &mgr;m, the geometric standard deviation of particle size distribution exceeds 1.4 and the degree of sphericity is 2 or less. Anodes for solid electrolytic capacitors which are suitable for the use of super-high capacity can be manufactured by using the improved powder.
    Type: Grant
    Filed: January 17, 2002
    Date of Patent: October 21, 2003
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventor: Nobuyuki Sato
  • Publication number: 20030178914
    Abstract: A domain controlled piezoelectric single crystal is disclosed which uses a lateral vibration mode for an electromechanical coupling factor k31 not less than 70% and a piezoelectric constant −d31 not less than 1200 pC/N, with an electromechanical coupling factor k33 in the longitudinal vibration mode not less than 80% and a piezoelectric constant d33 not less than 800 pC/N. Also, a piezoelectric single crystal is disclosed which uses a high-performance longitudinal vibration mode with k31 not more than 30%. A fabrication method applies a DC electric field of 400 V/mm to 1500 V/mm for a maximum of two hours in a temperature range of 20° C. to 200° C. as polarization conditions in the thickness direction of the piezoelectric single crystal. The method can include cooling, or heating and cooling between temperature boundaries of rhombohedral and tetragonal crystals or between tetragonal and cubic crystals or within a cubic crystal temperature range.
    Type: Application
    Filed: September 19, 2002
    Publication date: September 25, 2003
    Applicants: KAWATETSU MINING CO., LTD.
    Inventors: Toshio Ogawa, Mitsuyoshi Matsushita, Yoshihito Tachi