Patents by Inventor Hidetake Itoh

Hidetake Itoh 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: 7929390
    Abstract: When there is a defect area in a specific recording layer, recording of information is continued to restrain reduction in a recording rate. In an optical recording method for recording information on a multilayer optical recording medium having a plurality of recording layers by irradiating the recording layer with a beam spot, when a defect area is detected while the information is recorded on a specific recording layer selected from the plurality of recording layers, an escape recording layer which is selected from among the other recording layers except for the specific recording layer is irradiated with the beam spot to continue recording the information.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: April 19, 2011
    Assignee: TDK Corporation
    Inventors: Takashi Kikukawa, Koji Mishima, Hidetake Itoh
  • Publication number: 20110086264
    Abstract: An electro-chemical device comprises a package including a metal film, a battery element sealed within the package, resin layers disposed at least on the inside of a seal part of the package, and a lead extending from the battery element to the outside of the package through between the resin layers at the seal part of the package. The lead has a special form into which the resin of the resin layers bites, so that the lead is firmly buried in the resin layers, whereby the lead is fully inhibited from moving. Therefore, an electro-chemical device having a high quality can be obtained.
    Type: Application
    Filed: October 4, 2010
    Publication date: April 14, 2011
    Applicant: TDK CORPORATION
    Inventors: Naoto TSUKAMOTO, Hidetake ITOH, Yoshihiko OHASHI
  • Patent number: 7838097
    Abstract: A hardcoat agent composition comprising a fluorine-containing polyether compound (A) having a perfluoropolyether unit, urethane bond and active energy ray reactive group and a curable compound (B) having equal to or more than 2 active energy ray polymerizing groups in the molecule. An optical information medium having a film substance composed of single or multiple layers containing at least the recording layer 4 or the reflecting layer on the supporting substrate 20, the optical information medium wherein at least either the surface of the supporting substrate 20 or that of the above-mentioned film substance is formed by the hardcoat layer 8 containing a curable substance of the above-mentioned hardcoat agent composition.
    Type: Grant
    Filed: October 20, 2009
    Date of Patent: November 23, 2010
    Assignee: TDK Corporation
    Inventors: Naoki Hayashida, Rie Ihara, Hidetake Itoh, Kazushi Tanaka
  • Patent number: 7817526
    Abstract: An optical recording medium has a five-layer structure including five recording layers, namely an L0 layer, an L1 layer, an L2 layer, an L3 layer, and an L4 layer in this order from a side farthest away from a laser light incident surface. The materials of the respective recording layers are selected so that the rate of change in transmittance Tb/Ta as taken from the laser light incident surface satisfies 0.93<Tb/Ta<1.07 when recording on the L0 layer among the recording layers, where: Ta is transmittance of laser light to reach the L0 layer when the L0 layer is irradiated with the laser light of optimum recording power after recording marks are formed on all the recording layers closer to the laser light incident surface (being the L1 to L4 layers); and Tb is transmittance of laser light to reach the L0 layer when the L0 layer is irradiated with the laser light of optimum recording power with no recording mark formed on any of the recording layers closer to the laser light incident surface.
    Type: Grant
    Filed: August 20, 2007
    Date of Patent: October 19, 2010
    Assignee: TDK Corporation
    Inventors: Koji Mishima, Takashi Kikukawa, Hidetake Itoh
  • Publication number: 20100246095
    Abstract: An electric double layer capacitor comprising a plurality of electrode bodies comprising a positive electrode and a negative electrode laminated via a separator and being impregnated with an electrolyte solution, wherein the plurality of electrode bodies are electrically connected in series, the positive electrode and the negative electrode comprise an active material having pores, the electrolyte solution comprises an electrolyte having a cation and a counteranion of the cation, a ratio of an average pore diameter of the active material of the positive electrode to an ion diameter of the counteranion is in the range of 2.5 to 2.8, and a ratio of an average pore diameter of the active material of the negative electrode to an ion diameter of the cation is in the range of 1.65 to 1.85.
    Type: Application
    Filed: March 29, 2010
    Publication date: September 30, 2010
    Applicant: TDK CORPORATION
    Inventors: Yoshihiko OHASHI, Keita KOBAYASHI, Hidetake ITOH, Kazuo KATAI
  • Patent number: 7787334
    Abstract: When there is a defect area in a specific recording layer, recording of information is continued and reduction in a recording rate is restrained. In an optical recording method for recording information on a multilayer optical recording medium having a plurality of recording layers by irradiating the recording layer with a beam spot, any recording layer is set as an escape recording layer. When a defect area is detected while information is recorded on another recording layer except for the escape recording layer, the beam spot moves to the escape recording layer to continue recording the information.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: August 31, 2010
    Assignee: TDK Corporation
    Inventors: Takashi Kikukawa, Koji Mishima, Tsutomu Aoyama, Hidetake Itoh
  • Publication number: 20100124701
    Abstract: A lithium-ion secondary battery separator having a porous structure formed by laminating a second polymer layer, a first polymer layer, and a second polymer layer in sequence. The second polymer layer has a melting point higher than that of the first polymer layer. The second polymer layer has a higher molecular part formed on a side in contact with the first polymer layer and a lower molecular part formed on a side farther from the first polymer layer than is the higher molecular part. The higher and lower molecular parts have a weight-average molecular weight ratio (higher molecular part/lower molecular part) of 4 to 19 therebetween.
    Type: Application
    Filed: November 16, 2009
    Publication date: May 20, 2010
    Applicant: TDK CORPORATION
    Inventors: Katsuo NAOI, Kenji NISHIZAWA, Mitsuo KOUGO, Yoshihiko OHASHI, Hidetake ITOH
  • Patent number: 7697407
    Abstract: A multilayer optical recording medium enabled to retain an ideal signal regenerating property in spite of accidental adhesion of finger mark or alien substance is provided. The multilayer optical recording medium 1 is provided with a plurality of information-recording layers 20, 22, 24, and 26 capable of reading information with a reading light irradiated through a light incidence surface 38A on one side and is so adapted that the light incidence side information-recording layer 26 approximating most closely to the light incidence surface 38A may be set at a small recording capacity as compared with the recording capacities of at least one of the other information-recording layers.
    Type: Grant
    Filed: November 27, 2006
    Date of Patent: April 13, 2010
    Assignee: TDK Corporation
    Inventors: Koji Mishima, Takashi Kikukawa, Hidetake Itoh, Daisuke Yoshitoku
  • Publication number: 20100040823
    Abstract: A hardcoat agent composition comprising a fluorine-containing polyether compound (A) having a perfluoropolyether unit, urethane bond and active energy ray reactive group and a curable compound (B) having equal to or more than 2 active energy ray polymerizing groups in the molecule. An optical information medium having a film substance composed of single or multiple layers containing at least the recording layer 4 or the reflecting layer on the supporting substrate 20, the optical information medium wherein at least either the surface of the supporting substrate 20 or that of the above-mentioned film substance is formed by the hardcoat layer 8 containing a curable substance of the above-mentioned hardcoat agent composition.
    Type: Application
    Filed: October 20, 2009
    Publication date: February 18, 2010
    Applicant: TDK CORPORATION
    Inventors: Naoki Hayashida, Rie Ihara, Hidetake Itoh, Kazushi Tanaka
  • Patent number: 7632874
    Abstract: A hardcoat agent composition comprising a fluorine-containing polyether compound (A) having a perfluoropolyether unit, urethane bond and active energy ray reactive group and a curable compound (B) having equal to or more than 2 active energy ray polymerizing groups in the molecule. An optical information medium having a film substance composed of single or multiple layers containing at least the recording layer 4 or the reflecting layer on the supporting substrate 20, the optical information medium wherein at least either the surface of the supporting substrate 20 or that of the above-mentioned film substance is formed by the hardcoat layer 8 containing a curable substance of the above-mentioned hardcoat agent composition.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: December 15, 2009
    Assignee: TDK Corporation
    Inventors: Naoki Hayashida, Rie Ihara, Hidetake Itoh, Kazushi Tanaka
  • Patent number: 7524549
    Abstract: An optical information medium includes a light-transmitting supporting substrate, an information recording layer on one surface of the supporting substrate, a protective layer on the information recording layer, and a light-transmitting hard coat layer on an other surface of the supporting substrate. The medium is configured to have a recording/reproducing beam incident into the information recording layer through the hard coat later and the supporting substrate.
    Type: Grant
    Filed: September 17, 2007
    Date of Patent: April 28, 2009
    Assignee: TDK Corporation
    Inventors: Hidetake Itoh, Kazushi Tanaka, Naoki Hayashida, Hiroshi Take
  • Publication number: 20080279066
    Abstract: A signal quality evaluation method is provided that can objectively evaluate signal quality regardless of a PRML detection method used. The signal quality evaluation method is used when recording and reading is performed by irradiating a medium with a laser beam having a wavelength of ? through an objective lens having a numerical aperture of NA. In the signal quality evaluation method, information of the difference between an ideal signal recoded in the medium and a real signal obtained by irradiating the medium with the laser beam is statistically analyzed for each signal level of the ideal signal. The evaluation of the quality of the real signal is made using the statistics obtained by the statistical analysis.
    Type: Application
    Filed: May 5, 2008
    Publication date: November 13, 2008
    Inventors: Takashi Kikukawa, Hidetake Itoh
  • Publication number: 20080175124
    Abstract: When there is a defect area in a specific recording layer, recording of information is continued to restrain reduction in a recording rate. In an optical recording method for recording information on a multilayer optical recording medium having a plurality of recording layers by irradiating the recording layer with a beam spot, when a defect area is detected while the information is recorded on a specific recording layer selected from the plurality of recording layers, an escape recording layer which is selected from among the other recording layers except for the specific recording layer is irradiated with the beam spot to continue recording the information.
    Type: Application
    Filed: December 12, 2007
    Publication date: July 24, 2008
    Inventors: Takashi Kikukawa, Koji Mishima, Hidetake Itoh
  • Publication number: 20080170484
    Abstract: A reliable optical recording medium is provided which includes an information layer exhibiting small changes in the optical properties even during long-term storage. The optical recording medium includes the information layer including a recording film having an extinction coefficient of 0.4 or less at the wavelength of a laser beam used for recording and reproducing. The information layer further includes a light absorbing film having an extinction coefficient of 1.5 or less at the wavelength of the laser beam, and the extinction coefficient of the light absorbing film is greater than that of the recording film.
    Type: Application
    Filed: January 3, 2008
    Publication date: July 17, 2008
    Applicant: TDK CORPORATION
    Inventors: Koji Mishima, Takashi Kikukawa, Hidetake Itoh
  • Publication number: 20080170485
    Abstract: The optical recording medium includes a first information layer including a first recording film having an extinction coefficient of 0.4 or less at a wavelength of a laser beam used for recording and reproducing, and a second information layer including a second recording film consisting essentially of the same constituent elements as those of the first recording film and having an extinction coefficient of 0.4 or less. Among the first and second information layers, the first information layer is located further away from a laser beam-incident surface than the second information layer located closest to the incident surface. The first information layer further includes a light absorbing film having an extinction coefficient of 1.5 or more at the wavelength of the laser beam, the extinction coefficient of the light absorbing film being greater than that of the first recording film.
    Type: Application
    Filed: January 3, 2008
    Publication date: July 17, 2008
    Applicant: TDK CORPORATION
    Inventors: Koji Mishima, Hidetake Itoh, Takashi Kikukawa
  • Publication number: 20080151730
    Abstract: An optical recording and reading method capable of enhancing the design flexibility of recording layers of an optical recording medium and performing accurate optical recording and reading operations. The optical recording and reading method is one for recording and reading an optical recording medium having three or more recording layers by irradiating the same with laser light using an optical recording and reading apparatus. When an optical recording medium is mounted on the optical recording and reading apparatus, the positions of the recording layers of the optical recording medium are measured using the laser light.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 26, 2008
    Inventors: Takashi Kikukawa, Koji Mishima, Hidetake Itoh
  • Publication number: 20080151731
    Abstract: An optical recording and reading method capable of enhancing the design flexibility of recording layers of an optical recording medium and performing accurate optical recording and reading operations. A basic recording layer is arranged in a position that is in the range of 90 ?m to 110 ?m away from a light incident surface of an optical recording medium, and recording layers are arranged in parallel with the basic recording layer. At least the position information of the recording layers is recorded in one of the basic recording layer and the recording layers.
    Type: Application
    Filed: December 26, 2007
    Publication date: June 26, 2008
    Inventors: Hidetake Itoh, Koji Mishima, Takashi Kikukawa
  • Publication number: 20080130444
    Abstract: When there is a defect area in a specific recording layer, recording of information is continued and reduction in a recording rate is restrained. In an optical recording method for recording information on a multilayer optical recording medium having a plurality of recording layers by irradiating the recording layer with a beam spot, any recording layer is set as an escape recording layer. When a defect area is detected while information is recorded on another recording layer except for the escape recording layer, the beam spot moves to the escape recording layer to continue recording the information.
    Type: Application
    Filed: November 30, 2007
    Publication date: June 5, 2008
    Inventors: Takashi Kikukawa, Koji Mishima, Tsutomu Aoyama, Hidetake Itoh
  • Publication number: 20080068967
    Abstract: In a multilayer optical recording medium having three or more recording layers, when data is recorded on a recording layer far away from an incident surface of laser light, and especially on a recording layer farthest away from the incident surface of the laser light, by applying the laser light, the recording power margin of the farthest recording layer allows for a variation in the optimal recording sensitivity even if the transmittance of the recording layers located between the laser light incident surface side and the target recording layer is varied due to existing recordings and the amount of the laser light passing therethrough is also varied. In this case, the recording layer which is the farthest from an incident surface of laser light has a phase change recording film, and the recording layer which is the nearest from the incident surface of the laser light has a write-once read-multiple recording film.
    Type: Application
    Filed: September 12, 2007
    Publication date: March 20, 2008
    Applicant: TDK CORPORATION
    Inventors: Koji Mishima, Takashi Kikukawa, Hidetake Itoh
  • Patent number: 7338695
    Abstract: A simple method for evaluating an optical information medium by judging quantitatively and reproducibly the surface quality of the optical information medium by the use of an artificial fingerprint liquid as an evaluation dispersion liquid, is provided. An optical information medium having a remarkably excellent anti-staining property of the surface which is on the incident side of recording/reproducing beam is provided. A method for evaluating an optical information medium, comprising: adhering an artificial fingerprint liquid containing a fine-particle-form substance and a dispersion medium capable of dispersing the fine-particle-form substance onto the surface of the optical information medium which is on the incident side of a recording/reproducing beam; observing the state of the artificial fingerprint liquid droplets adhered to the surface; and judging the quality of the medium surface.
    Type: Grant
    Filed: April 15, 2005
    Date of Patent: March 4, 2008
    Assignee: TDK Corporation
    Inventors: Hidetake Itoh, Kazushi Tanaka, Naoki Hayashida, Hiroshi Take