Patents by Inventor Suguru Takayama

Suguru Takayama 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: 5571629
    Abstract: An optical recording medium comprising a recording layer on a substrate and an intermediate layer between the substrate and the recording layer exhibits high reflectance and corrosion resistance when the intermediate layer comprises silicon, aluminum, oxygen, nitrogen, and at least one element selected from the group consisting of yttrium, lanthanide elements and actinide elements, and contains 0.1 to 2 atom % of the element and 20 to 90 atom % of silicon and nitrogen combined or 2 to 35 atom % of the element and 20 to 95 atom % of silicon and nitrogen combined.
    Type: Grant
    Filed: August 29, 1994
    Date of Patent: November 5, 1996
    Assignee: TDK Corporation
    Inventors: Hajime Utsunomiya, Hideki Hirata, Kenji Uchiyama, Hideki Ishizaki, Suguru Takayama
  • Patent number: 5260921
    Abstract: Magneto-optical recording method for a magneto-optical recording disk using a non-flying magnetic head. The magnetic head produces a magnetic field extending from a primary magnetic pole and returning to an auxiliary magnetic pole while the disk is rotated. The magnetic head is spaced apart from one major surface of the disk such that the primary magnetic pole applies a magnetic field across the disk. Magneto-optical recording is effected in a magnetic field-modulation mode while properly controlling the projected area of the primary magnetic pole and the distance between the magnetic head and the disk surface. A satisfactory C/N is obtained in a consistent manner while jitter is reduced.
    Type: Grant
    Filed: September 28, 1992
    Date of Patent: November 9, 1993
    Assignee: TDK Corporation
    Inventors: Giichi Shibuya, Takashi Onodera, Suguru Takayama
  • Patent number: 5161150
    Abstract: An optical recording disk intended for use as an additionally recordable CD is provided. It has a substrate, a dye or recording layer on the substrate, and a reflective layer and a protective layer disposed on the recording layer in a close contact relationship. Recording is carried out by directing recording light to the recording layer to form a pit and reproduction is carried out by directing reproducing light to the pit. A layer containing a decomposition product of the dye or recording material, but substantially free of the substrate material is present at the interface between the substrate and the recording layer where the pit is formed.
    Type: Grant
    Filed: March 1, 1990
    Date of Patent: November 3, 1992
    Assignee: TDK Corporation
    Inventors: Kenryo Namba, Masahiro Shinkai, Sinichi Tezuka, Tetsushi Inoue, Toshiki Aoi, Suguru Takayama
  • Patent number: 4902584
    Abstract: An optical recording medium comprising a recording layer on a substrate and a protective layer formed adjacent to the upper or lower surface of the recording layer is more durable and corrosion resistant when the protective layer has a composition comprising silicon, a divalent metal such as Ba, Ca or Sr, oxygen, and nitrogen. An intermediate layer containing silicon, a metal or metalloid such as aluminum or lanthanum, oxygen and nitrogen is formed between the protective layer and the recording layer.
    Type: Grant
    Filed: December 23, 1987
    Date of Patent: February 20, 1990
    Assignee: TDK Corporation
    Inventors: Kenji Uchiyama, Hideki Ishizaki, Hajime Utsunomiya, Suguru Takayama
  • Patent number: 4861656
    Abstract: An optical recording medium comprising a recording layer on a substrate is more durable when an intermediate layer of a composition comprising a rare earth element oxide, silicon oxide, and silicon nitride is formed between the substrate and the recording layer.
    Type: Grant
    Filed: December 23, 1987
    Date of Patent: August 29, 1989
    Assignee: TDK Corporation
    Inventors: Kenji Uchiyama, Hideki Ishizaki, Suguru Takayama
  • Patent number: 4849304
    Abstract: An optical recording medium comprising a recording layer on a substrate and a protective layer formed adjacent to the upper and/or lower surface of the recording layer is more durable and corrosion resistant when the protective layer has a composition comprising, in % by weight, 40-60% of SiO.sub.2, 0.5-10% of an alkali metal oxide, 10-59.5% of Al.sub.2 O.sub.3 and/or B.sub.2 O.sub.3, and optionally up to 50% of a divalent metal oxide.
    Type: Grant
    Filed: December 16, 1987
    Date of Patent: July 18, 1989
    Assignee: TDK Corporation
    Inventors: Kenji Uchiyama, Hideki Ishizaki, Hajime Utsunomiya, Suguru Takayama
  • Patent number: 4837116
    Abstract: A magnetic recording medium comprising a ferromagnetic metal thin film layer primarily based on cobalt and formed on the surface of a flexible substrate, an organic topcoat layer containing a radiation curable compound having a molecular weight of less than 2,000, an anti-oxidant, and a lubricant on the surface of the metal thin film layer, and a backcoat layer containing an inorganic pigment, an organic binder, and a lubricant on the other surface of the substrate is provided with protrusions on its surface at an average density of at least 10.sup.5 /a.sup.2 per square millimeter of the surface, the protrusions having a height of 30 to 300 .ANG., where a is the distance of a gap in a magnetic head with which the medium is used in recording/reproducing operation.
    Type: Grant
    Filed: December 2, 1987
    Date of Patent: June 6, 1989
    Assignee: TDK Corporation
    Inventors: Hiroyuki Arioka, Masaharu Nishimatsu, Suguru Takayama
  • Patent number: 4835032
    Abstract: A magnetic recording medium comprising a ferromagnetic metal thin film layer primarily based on cobalt and formed on the surface of a flexible substrate, an organic topcoat layer containing a radiation-curable compound, an anti-oxidant, and optionally a lubricant on the surface of the metal thin film layer, and a backcoat layer containing an inorganic pigment, an organic binder, and a lubricant on the other surface of the substrate is provided with protrusions on its surface at an average density of at least 10.sup.5 /a.sup.2 per square millimeter of the surface, the protrusions having a height of 30 to 300 .ANG., where a is the distance of a gap in a magnetic head with which the medium is used in recording/reproducing operation.
    Type: Grant
    Filed: December 2, 1987
    Date of Patent: May 30, 1989
    Assignee: TDK Corporation
    Inventors: Hiroyuki Arioka, Masaharu Nishimatsu, Suguru Takayama
  • Patent number: 4828899
    Abstract: A magnetic recording medium comprising a ferromagnetic metal thin film layer primarily based on cobalt and formed on the surface of a flexible substrate, and an organic topcoat layer containing a radiation curable compound having a molecular weight of less than 2,000, an anti-oxidant, and a lubricant on the surface of the metal thin film layer is provided with protrusions on its surface at an average density of at least 10.sup.5 /a.sup.2 per square millimeter of the surface, the protrusions having a height of 30 to 300 .ANG. where a is the distance of a gap in a magnetic head across which the medium is passed in recording/reproducing operation.
    Type: Grant
    Filed: December 2, 1987
    Date of Patent: May 9, 1989
    Assignee: TDK Corporation
    Inventors: Hiroyuki Arioka, Masaharu Nishimatsu, Suguru Takayama
  • Patent number: 4778707
    Abstract: A magnetic recording medium comprising a ferromagnetic metal thin film layer primarily based on cobalt and formed on the surface of a flexible substrate, an organic topcoat layer containing an anti-oxidant and a lubricant on the surface of the metal thin film layer, and a backcoat layer containing an inorganic pigment, an organic binder, and a lubricant on the other surface of the substrate is provided with protrusions on its surface at an average density of at least 10.sup.5 /a.sup.2 per square millimeter of the surface, the protrusions having a height of 30 to 300 .ANG., where a is the distance of a gap in a magnetic head with which the medium is used in recording/reproducing operation.
    Type: Grant
    Filed: March 4, 1987
    Date of Patent: October 18, 1988
    Assignee: TDK Corporation
    Inventors: Hiroyuki Arioka, Masaharu Nishimatsu, Suguru Takayama
  • Patent number: 4777082
    Abstract: In an optical recording medium comprising a substrate and a recording layer thin film comprised of a rare earth element and a transition metal, for example, TbFeCo on the substrate, a metal thin film layer having a high magnetic permeability, for example, Permalloy is formed on the recording layer. A transparent dielectric film layer may be formed between the substrate and the recording layer thin film.
    Type: Grant
    Filed: August 17, 1987
    Date of Patent: October 11, 1988
    Assignee: TDK Corporation
    Inventors: Hideki Ishizaki, Takayoshi Kobuke, Suguru Takayama
  • Patent number: 4701375
    Abstract: A magnetic recording medium, comprising a non-magnetic substrate, a magnetic recording layer of ferromagnetic film formed on one side of said substrate, and a topcoat layer comprising an antioxidant and a lubricant and formed on the surface of said magnetic recording layer.
    Type: Grant
    Filed: October 24, 1986
    Date of Patent: October 20, 1987
    Assignee: TDK Corporation
    Inventors: Masaharu Nishimatsu, Suguru Takayama, Hiroyuki Arioka
  • Patent number: 4637843
    Abstract: The present invention relates to the core of a noise filter.Conventionally, ferrite or iron powder is used as the core of a noise filter. Some patent publications disclose the core of a noise filter made of an amorphous magnetic alloy.An amorphous magnetic alloy which as a low pulse-noise resistance deterioration percentage is that on or within the curve X and Y of FIG. 3.
    Type: Grant
    Filed: May 3, 1985
    Date of Patent: January 20, 1987
    Assignee: TDK Corporation
    Inventors: Suguru Takayama, Masao Shigeta
  • Patent number: 4596735
    Abstract: In a magnetic recording medium comprising a non-magnetic substrate and a magnetic layer of Co or Co-Ni in the form of a continuous thin film on the substrate, the magnetic layer has oxygen-rich sub-layers at its surfaces adjacent to and remote from the substrate. The oxygen-rich sub-layers are produced by injecting energy particles containing oxygen to the surface of the substrate during the initial and final stages of formation of the magnetic layer.
    Type: Grant
    Filed: April 25, 1984
    Date of Patent: June 24, 1986
    Assignee: TDK Corporation
    Inventors: Kiyoshi Noguchi, Koji Kobayashi, Suguru Takayama
  • Patent number: 4594296
    Abstract: A magnetic recording medium which comprises a magnetic layer formed on a substrate and comprising Co, or Co and one to three elements selected from the group consisting of Ni, Cr and O, wherein, when the magnetic layer is divided equally into four portions in the direction of the thickness of the magnetic layer, the density of the portion located farthest from the substrate is greater by at least 20% than the average density of three other portions.
    Type: Grant
    Filed: December 16, 1983
    Date of Patent: June 10, 1986
    Assignee: TDK Corporation
    Inventors: Kiyoshi Noguchi, Kouji Kobayashi, Suguru Takayama
  • Patent number: 4587507
    Abstract: Conventionally, silicon steel strips and ferrite cores have been used as the core of a choke coil. These strips and the like have not yet been replaced with amorphous alloy because in the known amorphous magnetic alloy the pre-magnetization characteristic, the amount of heat generated, and the secular change are poor.The present invention proposes a core of a choke coil which consists of a coiled thin strip of an amorphous alloy, and has at least one cut air gap, the coiled regions of the thin strip being bound to one another at at least in the neighborhood of said at least one cut air gap, and said amorphous magnetic alloy is essentially comprised of the following composition, Fe.sub.x Mn.sub.y (Si.sub.p B.sub.q P.sub.r C.sub.s).sub.z, wherein x+y+z is 100 atomic % based on all of the elements, y is from 0.001 to 10 atomic %, z is from 21 to 25.5 atomic %, p+q+r+s is atomic % 1, p is from 0.40 to 0.75, r is fro 0.0001 to 0.05, the ratio s/q is from 0.03 to 0.4, and z is z.ltoreq.50p+1, z.ltoreq.10p+19, z.
    Type: Grant
    Filed: November 23, 1982
    Date of Patent: May 6, 1986
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Suguru Takayama, Masao Shigeta
  • Patent number: 4550062
    Abstract: A magnetic recording medium which comprises a first layer formed on a substrate and comprising Co; Co and Ni; Co and O; or Co, Ni and O, and a second magnetic layer formed on the first magnetic layer and comprising Co and Cr at a weight ratio of Co/Cr being from 2.5 to 8.
    Type: Grant
    Filed: December 15, 1983
    Date of Patent: October 29, 1985
    Assignee: TDK Corporation
    Inventors: Suguru Takayama, Kiyoshi Noguchi, Kouji Kobayashi
  • Patent number: 4548871
    Abstract: A magnetic recording medium which comprises a magnetic layer formed on a substrate and comprising Co, or Co and one to three elements selected from the group consisting of Ni, Cr and O, said magnetic layer comprising sequentially from the substrate side, a first portion composed of crystal particles which are not inclined relative to the normal line of the principal plane of the substrate, a second portion composed of columnar crystal particles which are inclined relative to the normal line of the principal plane of the substrate, and a third portion composed of crystal particles which are not inclined relative to the normal line of the principal plane of the substrate.
    Type: Grant
    Filed: December 16, 1983
    Date of Patent: October 22, 1985
    Assignee: TDK Corporation
    Inventors: Kouji Kobayashi, Kiyoshi Noguchi, Suguru Takayama
  • Patent number: 4540600
    Abstract: A process for producing a magnetic recording medium which comprises forming on a non-magnetic substrate a magnetic thin layer composed of columnar crystal particles comprising Co, or Co and Ni and/or Cr by vapor/depositing the metal atoms at an angle of incidence of at least 20.degree. relative to the normal line of the principal plane of the substrate, and then forcibly oxidizing the magnetic thin layer by electrochemical treatment to form an oxide layer on the surface of the columnar crystal particles of the magnetic thin layer, and thereby to form a magnetic layer.
    Type: Grant
    Filed: March 12, 1984
    Date of Patent: September 10, 1985
    Assignee: TDK Corporation
    Inventors: Koji Kobayashi, Kiyoshi Noguchi, Suguru Takayama
  • Patent number: 4183829
    Abstract: Catalysts for purification of exhaust gases from internal combustion engines which are a mixture of aluminum oxide, calcium oxide and one or more of the elements platinum, palladium and rhodium, and method for their use.
    Type: Grant
    Filed: March 23, 1978
    Date of Patent: January 15, 1980
    Assignee: TDK Electronics Co. Ltd.
    Inventors: Shichiro Adachi, Suguru Takayama, Takuo Sato