Patents by Inventor Katsuhiko Yamazaki

Katsuhiko Yamazaki 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: 7432000
    Abstract: The present invention provides a magnetic recording medium which has a back coat layer excellent in surface smoothness and durability and is excellent in electromagnetic conversion property. A magnetic recording medium, comprising at least a non-magnetic support, a lower non-magnetic layer on one surface of the non-magnetic support, an upper magnetic layer on the lower non-magnetic layer, and a back coat layer on the other surface of the non-magnetic support, wherein the lower non-magnetic layer contains at least carbon black, a non-magnetic inorganic powder other than carbon black, and a binder resin material, the upper magnetic layer contains at least a ferromagnetic powder, and a binder resin material, and the back coat layer contains at least carbon black, a non-magnetic inorganic powder other than carbon black, a carboxylic acid amine salt, a phosphate amine salt, and a binder resin material.
    Type: Grant
    Filed: December 19, 2006
    Date of Patent: October 7, 2008
    Assignee: TDK Corporation
    Inventors: Takayoshi Kuwajima, Katsuhiko Yamazaki
  • Patent number: 7425378
    Abstract: The present invention provides a magnetic recording medium which has a thin film magnetic layer considerably excellent in surface smoothness, and is excellent in electromagnetic conversion property. A magnetic recording medium comprising a non-magnetic support, a lower non-magnetic layer comprising at least a non-magnetic powder and a binder resin on one surface of the non-magnetic support, and a magnetic layer comprising at least a ferromagnetic powder and a binder resin on the lower non-magnetic layer, wherein when the magnetic recording medium is subjected to extraction treatment with water, 7 to 23 ?g of PO43? ions are extracted per 10 mm3 of the volume of the lower non-magnetic layer of the magnetic recording medium.
    Type: Grant
    Filed: July 26, 2004
    Date of Patent: September 16, 2008
    Assignee: TDK Corporation
    Inventors: Katsuhiko Yamazaki, Tsutomu Ide, Takashi Handa, Akinori Nishizawa
  • Publication number: 20080145710
    Abstract: The present invention provides a high-capacity magnetic recording medium which has a thinned back coat layer excellent in surface smoothness and durability and is excellent in electromagnetic conversion property. A magnetic recording medium comprising at least a non-magnetic support, a lower non-magnetic layer on one surface of the non-magnetic support, an upper magnetic layer on the lower non-magnetic layer, and a back coat layer on the other surface of the non-magnetic support, wherein the lower non-magnetic layer contains at least carbon black, a non-magnetic inorganic powder other than carbon black, and a binder resin material, the upper magnetic layer contains at least a ferromagnetic powder, and a binder resin material, and the back coat layer contains at least carbon black, a non-magnetic inorganic powder other than carbon black, a phosphate amine salt, and nitrocellulose resin as a binder resin material, and has a thickness of 0.3 to 0.8 ?m.
    Type: Application
    Filed: December 17, 2007
    Publication date: June 19, 2008
    Applicant: TDK Corporation
    Inventors: Takayoshi KUWAJIMA, Katsuhiko Yamazaki
  • Publication number: 20080017073
    Abstract: A method for manufacturing magnetic paint or non-magnetic paint, which can produce a magnetic recording medium having excellent surface smoothness by appropriately setting the condition of a dispersion process for improving the dispersibility of the paint, and a magnetic recording medium are provided. The magnetic paint or the non-magnetic paint is produced by performing a dispersion process of a mixed solution, in which a magnetic powder or a non-magnetic powder is mixed into a binder solution containing a binder and a solvent, with a medium dispersion device. The method includes the steps of adjusting the viscosity of the mixed solution to 1,500 cP or less on a BL type viscometer at 20 rpm basis, and performing a dispersion process with the medium dispersion device using dispersion media having an average particle diameter of 0.5 mm or less at a dispersion circumferential speed of 8 to 15 m/s.
    Type: Application
    Filed: September 20, 2007
    Publication date: January 24, 2008
    Applicant: TDK CORPORATION
    Inventors: Katsuhiko YAMAZAKI, Tsutomu Ide
  • Patent number: 7288210
    Abstract: A method for manufacturing magnetic paint or non-magnetic paint, which can produce a magnetic recording medium having excellent surface smoothness by appropriately setting the condition of a dispersion process for improving the dispersibility of the paint, and a magnetic recording medium are provided. The magnetic paint or the non-magnetic paint is produced by performing a dispersion process of a mixed solution, in which a magnetic powder or a non-magnetic powder is mixed into a binder solution containing a binder and a solvent, with a medium dispersion device. The method includes the steps of adjusting the viscosity of the mixed solution to 1,500 cP or less on a BL type viscometer at 20 rpm basis, and performing a dispersion process with the medium dispersion device using dispersion media having an average particle diameter of 0.5 mm or less at a dispersion circumferential speed of 8 to 15 m/s.
    Type: Grant
    Filed: February 3, 2006
    Date of Patent: October 30, 2007
    Assignee: TDK Corporation
    Inventors: Katsuhiko Yamazaki, Tsutomu Ide
  • Publication number: 20070231471
    Abstract: A method for manufacturing a magnetic recording medium is provided which has high recording density and which is less likely to cause problems of a magnetic tape such as inappropriate contact with a head, unstable running, and damage. A back-coat layer containing plate-like inorganic pigment (plate-like inorganic pigment-containing layer) is formed over a non-magnetic support to produce an intermediate product having the support and the back-coat layer. Then, the intermediate product is subjected to calendering between at least one pair of metal rolls.
    Type: Application
    Filed: March 26, 2007
    Publication date: October 4, 2007
    Applicant: TDK CORPORATION
    Inventors: Katsuhiko Yamazaki, Tsutomu Ide
  • Publication number: 20070141402
    Abstract: The present invention provides a magnetic recording medium which has a back coat layer excellent in surface smoothness and durability and is excellent in electromagnetic conversion property. A magnetic recording medium, comprising at least a non-magnetic support, a lower non-magnetic layer on one surface of the non-magnetic support, an upper magnetic layer on the lower non-magnetic layer, and a back coat layer on the other surface of the non-magnetic support, wherein the lower non-magnetic layer contains at least carbon black, a non-magnetic inorganic powder other than carbon black, and a binder resin material, the upper magnetic layer contains at least a ferromagnetic powder, and a binder resin material, and the back coat layer contains at least carbon black, a non-magnetic inorganic powder other than carbon black, a carboxylic acid amine salt, a phosphate amine salt, and a binder resin material.
    Type: Application
    Filed: December 19, 2006
    Publication date: June 21, 2007
    Applicant: TDK CORPORATION
    Inventors: Takayoshi KUWAJIMA, Katsuhiko Yamazaki
  • Patent number: 7198733
    Abstract: A formed substrate, wherein the surface of the valve-acting metal having a dielectric film is at least partially covered with an oxide comprising Si, valve-acting metal element and oxygen, preferably, wherein the content of Si in the formed foil having an aluminum oxide dielectric film decreases continuously from the surface of the dielectric film toward the inner part in some regions in the aluminum dielectric film thickness; a method for producing the formed substrate; and a solid electrolytic capacitor comprising a solid electrolyte on the formed substrate. A solid electrolytic capacitor manufactured by using a formed substrate according to the present invention, improved in adhesion to an electrically conducting polymer (solid electrolyte) with its area coverage contacting the polymer being sufficiently large, is increased in the electrostatic capacitance among individual capacitors and improved in the LC yield as compared with capacitors otherwise manufactured.
    Type: Grant
    Filed: June 11, 2002
    Date of Patent: April 3, 2007
    Assignee: Showa Denko K.K.
    Inventors: Hiroshi Konuma, Katsuhiko Yamazaki, Takenori Umikawa, Masakazu Yagi, Tamotsu Yamashita
  • Patent number: 7175781
    Abstract: A solid electrolytic capacitor includes a valve acting metal having microfine pores, a dielectric film formed on a surface of the valve acting metal, and a solid electrolyte layer provided on the dielectric film, in which at least a portion of the solid electrolyte layer is of a lamellar structure. In particular, a solid electrolytic capacitor includes an electrically conducting polymer having a specified condensed ring structure containing (1) a solid electrolyte layer containing a sulfoquinone anion, and (2) a solid electrolyte layer containing an anthracenesulfonate ion and other anion.
    Type: Grant
    Filed: September 14, 2004
    Date of Patent: February 13, 2007
    Assignee: Showa Denko K.K.
    Inventors: Hiroshi Konuma, Koro Shirane, Ryuji Monden, Atsushi Sakai, Yuji Furuta, Katsuhiko Yamazaki, Toru Sawaguchi, Hideko Ohata, Yoshiaki Ikenoue
  • Publication number: 20070009655
    Abstract: A method of manufacturing a magnetic recording medium comprising forming a reinforcing layer on a first surface of a non-magnetic support, performing a surface treatment that applies external energy to a surface of the reinforcing layer, and forming a functional layer on the surface of the reinforcing layer that has been subjected to the surface treatment. By doing so, the functional layer can be prevented from peeling off the reinforcing layer with no increase in manufacturing cost or fall in manufacturing yield.
    Type: Application
    Filed: July 5, 2006
    Publication date: January 11, 2007
    Applicant: TDK CORPORATION
    Inventors: Katsuhiko YAMAZAKI, Tsutomu IDE
  • Patent number: 7160481
    Abstract: A method for manufacturing magnetic paint is provided, wherein a dispersion condition is appropriately controlled to excellently disperse a magnetic powder composed of fine particles adaptable for a higher recording density, so that magnetic paint having excellent dispersibility can be prepared, and a magnetic recording medium having excellent surface roughness is provided. The magnetic paint is prepared by the step of subjecting a mixed solution containing at least a binder, a solvent, and a magnetic powder to a dispersion treatment with a dispersion device by the use of dispersion media through at least dispersion step, wherein the dispersion in the main dispersion step is carried out by the use of dispersion media having an average particle diameter y (mm) satisfying the relationship, which is represented by formula y?0.01x, with the average maximum diameter x (nm) of the magnetic powder.
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: January 9, 2007
    Assignee: TDK Corporation
    Inventors: Katsuhiko Yamazaki, Tsutomu Ide, Hiroyuki Tanaka
  • Publication number: 20060292402
    Abstract: A magnetic recording medium has at least a non-magnetic layer and a magnetic layer formed in that order on one surface of a non-magnetic support. The non-magnetic layer is formed using a non-magnetic coating composition including a (meth)acryloyl group in a range of 11 mmol to 30 mmol, inclusive relative to 100 parts by weight of non-magnetic powder.
    Type: Application
    Filed: June 14, 2006
    Publication date: December 28, 2006
    Applicant: TDK CORPORATION
    Inventors: Tsutomu IDE, Katsuhiko YAMAZAKI, Tomoyuki KOTAKI
  • Publication number: 20060222906
    Abstract: A radiation curing polyurethane resin for a magnetic recording medium which is capable of realizing a lower non-magnetic layer that can secure sufficient coating film strength with a lower radiation dose. A polyurethane resin which contains active hydrogen, and a sulfur-containing polar group in an amount of not less than 0.05 mmol/g to not more than 0.10 mmol/g, inclusive, but does not contain a basic polar group in its molecule and is formed only by an aliphatic segment, is modified on the active hydrogen into a radiation curing polyurethane resin by a compound having an acrylic double bond.
    Type: Application
    Filed: March 30, 2006
    Publication date: October 5, 2006
    Applicant: TDK Corporation
    Inventors: Hiroyuki Tanaka, Tsutomu Ide, Katsuhiko Yamazaki
  • Publication number: 20060210839
    Abstract: A magnetic recording medium which makes it possible to further increase the recording capacity while maintaining a required flexibility thereof. A magnetic tape has a lower non-magnetic layer and a magnetic layer formed on one surface of a base film in the mentioned order. The lower non-magnetic layer is formed of a non-magnetic coating material containing a non-magnetic powder, an electron beam curing binder, a dispersant having an amine group, and a thermosetting agent.
    Type: Application
    Filed: March 14, 2006
    Publication date: September 21, 2006
    Applicant: TDK Corporation
    Inventors: Tsutomu Ide, Katsuhiko Yamazaki, Tomoyuki Kotaki, Sadafumi Iijima
  • Publication number: 20060179627
    Abstract: A method for producing a solid electrolytic capacitor, comprising coating a solution containing a monomer of an electroconducting polymer and a solution containing an oxidizing agent in repeating sequence on a valve-acting metal anode having formed on the surface thereof an oxide dielectric film, and then polymerizing wherein the electroconducting polymer is formed by setting the humidity in the atmosphere of polymerization process to from 10% to less than 60%.
    Type: Application
    Filed: April 6, 2006
    Publication date: August 17, 2006
    Inventors: Atsushi Sakai, Ryuji Monden, Toru Sawaguchi, Katsuhiko Yamazaki, Yuji Furuta, Hideki Ohata
  • Patent number: 7087292
    Abstract: A solid electrolytic capacitor comprises an electrically conducting polymer composition formed on the surface of an oxide film which is formed on a valve-acting metal, by specifying the viscosity of an oxidizing agent solution and/or a monomer solution, particularly by specifying the viscosity to less than about 100 cp. A solid electrolytic capacitor can comprise an electroconducting polymer composition formed on the surface of an oxide film layer which is formed on a valve-acting metal, wherein a monomer compound or a derivative thereof as a repeating unit is polymerized by setting the humidity in the atmosphere to from about 10% to less than about 60%.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: August 8, 2006
    Assignee: Showa Denko K.K.
    Inventors: Atsushi Sakai, Ryuji Monden, Toru Sawaguchi, Katsuhiko Yamazaki, Yuji Furuta, Hideki Ohata
  • Publication number: 20060124887
    Abstract: A method for manufacturing magnetic paint or non-magnetic paint, which can produce a magnetic recording medium having excellent surface smoothness by appropriately setting the condition of a dispersion process for improving the dispersibility of the paint, and a magnetic recording medium are provided. The magnetic paint or the non-magnetic paint is produced by performing a dispersion process of a mixed solution, in which a magnetic powder or a non-magnetic powder is mixed into a binder solution containing a binder and a solvent, with a medium dispersion device. The method includes the steps of adjusting the viscosity of the mixed solution to 1,500 cP or less on a BL type viscometer at 20 rpm basis, and performing a dispersion process with the medium dispersion device using dispersion media having an average particle diameter of 0.5 mm or less at a dispersion circumferential speed of 8 to 15 m/s.
    Type: Application
    Filed: February 3, 2006
    Publication date: June 15, 2006
    Applicant: TDK Corporation
    Inventors: Katsuhiko Yamazaki, Tsutomu Ide
  • Patent number: 7060205
    Abstract: The present invention relates to a solid electrolytic capacitor comprising a solid electrolyte layer and an electrically conducting layer comprising metallic powder or an electrically conducting layer comprising an electrically conducting carbon layer and a layer formed thereon and comprising metallic powder in which at least one of said layers contains a rubber-like elastic material; a production process thereof; a solid electrolyte for use in the solid electrolytic capacitor; a production process of the solid electrolyte; an electrically conducting paste for use in the solid electrolytic capacitor; and an electrically carbon conducting paste for use in the solid electrolytic capacitor. The solid electrolytic capacitor of the present invention can be made compact and can be endowed with high-capacitance and low-impedance and is excellent in external force-relaxing properties, productivity, heat resistance and moisture resistance, etc.
    Type: Grant
    Filed: May 18, 2004
    Date of Patent: June 13, 2006
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Ryuji Monden, Katsuhiko Yamazaki, Atsushi Sakai, Yuji Furuta, Hideki Ohata, Koro Shirane, Hiroshi Konuma
  • Publication number: 20060019127
    Abstract: The present invention provides a magnetic recording medium which has a thin film magnetic layer considerably excellent in surface smoothness, and is excellent in electromagnetic conversion property. A magnetic recording medium comprising a non-magnetic support, a lower non-magnetic layer comprising at least a non-magnetic powder and a binder resin on one surface of the non-magnetic support, and a magnetic layer comprising at least a ferromagnetic powder and a binder resin on the lower non-magnetic layer, wherein when the magnetic recording medium is subjected to extraction treatment with water, 7 to 23 ?g of PO43? ions are extracted per 10 mm3 of the volume of the lower non-magnetic layer of the magnetic recording medium.
    Type: Application
    Filed: July 26, 2004
    Publication date: January 26, 2006
    Applicant: TDK CORPORATION
    Inventors: Katsuhiko Yamazaki, Tsutomu Ide, Takashi Handa, Akinori Nishizawa
  • Patent number: 6954351
    Abstract: A method for producing a solid electrolytic capacitor, involving a step of loading a metal oxide on at least a part of the surface in the anode part of a capacitor element having a valve-acting metal substrate having there on a solid electrolyte, the valve-acting metal substrate having a dielectric film obtained by the electrochemical forming, and a solid electrolytic capacitor obtained by stacking two or more single plate capacitor elements having a metal oxide on at least a part of the surface in the anode part of a capacitor element comprising a valve-acting metal substrate having thereon a solid electrolyte, the valve-acting metal substrate having a dielectric film obtained by the electrochemical forming.
    Type: Grant
    Filed: August 21, 2002
    Date of Patent: October 11, 2005
    Assignee: Showa Denko K.K.
    Inventors: Hiroshi Konuma, Eiji Komazawa, Katsuhiko Yamazaki