Patents by Inventor Keisuke Iwasaki

Keisuke Iwasaki 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: 6124022
    Abstract: Acicular hematite particles of the present invention comprise a geometrical standard deviation of major axis diameter of not more than 1.50, a geometrical standard deviation of minor axis diameter of not more than 1.35, a BET specific surface area of 35.9 to 150 m.sup.2 /g and an average major axis diameter of 0.004 to 0.295 .mu.m. Such acicular hematite particles are suitable as non-magnetic particles for a non-magnetic undercoat layer of a magnetic recording medium having a low light transmittance, an excellent smooth surface, a high mechanical strength and an excellent durability.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: September 26, 2000
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Yasuyuki Tanaka, Keisuke Iwasaki, Hiroko Morii
  • Patent number: 6120898
    Abstract: The present invention relates to acicular hematite particles containing aluminum of 0.05 to 50% by weight, calculated as Al, having an average major axial diameter of not more than 0.3 .mu.m and a pH value of the particles of not less than 8, and containing soluble sodium salts of not more than 300 ppm soluble sodium, calculated as Na, and soluble sulfates of not more than 150 ppm soluble sulfate, calculated as SO.sub.4, which have an excellent dispersibility in a binder resin, and a magnetic recording medium which uses the hematite particles as non-magnetic particles for a non-magnetic undercoat layer, which has small light transmittance, smooth surface, high strength and high durability, and which is capable of suppressing the deterioration in the magnetic properties caused by a corrosion of the magnetic particles containing as a main ingredient in the magnetic recording layer.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: September 19, 2000
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Hiroko Morii, Yasuyuki Tanaka
  • Patent number: 6072627
    Abstract: A stereoscopic image capture device of this invention includes: an image capturing face on which light from an object is incident; an optical element disposed on a side of the image capturing face on which the light is incident, the optical element converting an angle at which the light is incident thereon to a distance from an optical axis the optical element; and an afocal optical system including a plurality of lenses, wherein the afocal optical system forms, on the optical element, an image of the object formed on one of the plurality of lenses which is closest to the object.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: June 6, 2000
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshio Nomura, Masayuki Katagiri, Keisuke Iwasaki, Noritoshi Kako
  • Patent number: 6063490
    Abstract: A magnetic recording medium of the present invention comprises: a base film; a non-magnetic undercoat layer formed on said base film and comprising a binder resin and non-magnetic acicular particles containing iron as a main component, comprising iron and titanium of 0.05 to 50% by weight, calculated as Ti, based on the total weight of the particles, which is present within the particle; and a magnetic recording layer formed on said non-magnetic undercoat layer and comprising magnetic particles and a binder resin. Such a magnetic recording medium has a low light transmittance, an excellent smooth surface, a high mechanical strength and an excellent durability.
    Type: Grant
    Filed: August 12, 1998
    Date of Patent: May 16, 2000
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Toshiharu Harada, Hiroko Morii
  • Patent number: 6054201
    Abstract: The present invention relates to a magnetic recording medium comprising: a non-magnetic substrate; a non-magnetic undercoat layer formed on said non-magnetic substrate, said undercoat layer comprising non-magnetic acicular hematite particles containing 0.05 to 50% by weight of aluminum uniformly within the particles, calculated as Al, based on the total weight of the non-magnetic particles and a binder resin,; and a magnetic recording layer formed on said non-magnetic undercoat layer, said magnetic recording layer comprising magnetic particles containing iron as a main ingredient and a binder resin. The magnetic recording medium has small light transmittance, smooth surface, high strength and high durability.
    Type: Grant
    Filed: February 26, 1998
    Date of Patent: April 25, 2000
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Hiroko Morii, Yasuyuki Tanaka
  • Patent number: 6042937
    Abstract: The present invention relates to titanium oxide particles having an average particle size of not more than 0.3 .mu.m, and a BET specific surface area of 15 to 200 m.sup.2 /g, containing a soluble sodium salt of not more than 230 ppm, calculated as Na, and a soluble sulfate of not more than 150 ppm, calculated as SO.sub.4, and having a pH value of not less than 8. The titanium oxide particles of the present invention are suitable as non-magnetic particles for a non-magnetic undercoat layer of a magnetic recording medium which uses magnetic particles containing iron as a main ingredient, and even more particularly, are suitable as non-magnetic particles for a non-magnetic undercoat layer of a magnetic recording medium which uses magnetic particles containing iron as a main ingredient, show an excellent dispersibility in a binder resin, contain only a small amount of soluble sodium salt and soluble sulfate, and have a pH value of not less than 8.
    Type: Grant
    Filed: December 15, 1997
    Date of Patent: March 28, 2000
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Hiroko Morii
  • Patent number: 6030688
    Abstract: Rectangular parallelopipedic lepidocrocite particles of the present invention have a minor axial diameter of 0.045 to 0.5 .mu.m, a major axial diameter of 0.05 to 1.0 .mu.m, and a thickness of 0.001 to 0.3 .mu.m, which are individual. Such rectangular parallelopipedic lepidocrocite particles according to the present invention are firstly used as a coloring pigment for paints, resin moldings, printing ink, road asphalt, cosmetics, etc., and secondly used as a non-magnetic material for non-magnetic undercoat layers which are formed on non-magnetic substrates which constitute a substrate for magnetic recording media, and which have an excellent surface smoothness and a high strength.
    Type: Grant
    Filed: August 8, 1997
    Date of Patent: February 29, 2000
    Assignee: Toda Kogyo Cororation
    Inventors: Kazuyuki Hayashi, Hiroko Morii, Yoshiro Okuda, Keisuke Iwasaki
  • Patent number: 5949390
    Abstract: A three-dimensional display apparatus includes a liquid crystal panel 1 for displaying a discrete Fourier transformed image and a slit panel 2 having a convex lens function in a horizontal direction and a plurality of slits 3 arranged in a zig-zag manner, which is disposed in front of the liquid crystal panel 1. Since a spatial image is generated by such a configuration, a wide viewing region can be obtained. Since the number of slits positioned in the horizontal direction is increased as that of a slit pattern of a conventional slit array, the deterioration of resolution in the horizontal direction is reduced. Furthermore, since the slits are arranged in a zig-zag manner, the area of each light-shielding portion between sampling positions is reduced, thereby preventing an optical means from obstructing the observation of images.
    Type: Grant
    Filed: June 27, 1996
    Date of Patent: September 7, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshio Nomura, Masayuki Katagiri, Keisuke Iwasaki, Noritoshi Kako
  • Patent number: 5882795
    Abstract: The disclosure describes a non-magnetic undercoating layer for a magnetic recording medium, coated on the surface of a non-magnetic substrate comprising:non-magnetic particles selected from the group consisting of particles (1) and (2):(1) coated acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles which are produced by adhering not less than 0.01 to 20 wt % (calculated as Al, SiO.sub.2 or Al and SiO.sub.2, and based on acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material) of an oxide or a hydroxide containing Al, Si or both Al and Si to the surfaces of acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material, and have a molecular weight-dependent parameter .alpha. represented by the following formula of not less than 0.5:As=K.sub.1 .multidot.M.sup..alpha.wherein M represents the number-average molecular weight of a binder resin, As represents the saturation adsorption of said binder resin, and K.sub.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: March 16, 1999
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Minoru Ohsugi, Hiroko Morii, Mineko Sakoda, Norio Sugita, Masaaki Maekawa
  • Patent number: 5830557
    Abstract: The disclosure describes a non-magnetic undercoating layer for a magnetic recording medium, coated on the surface of a non-magnetic substrate comprising:non-magnetic particles selected from the group consisting of particles (1) and (2):(1) coated acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles which are produced by adhering not less than 0.01 to 20 wt % (calculated as Al, SiO.sub.2 or Al and SiO.sub.2, and based on acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material) of an oxide or a hydroxide containing Al, Si or both Al and Si to the surfaces of acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material, and have a molecular weight-dependent parameter .alpha. represented by the following formula of not less than 0.5:As=K.sub.1 .multidot.M.sup..alpha.wherein M represents the number-average molecular weight of a binder resin, As represents the saturation adsorption of said binder resin, and K.sub.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: November 3, 1998
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Minoru Ohsugi, Hiroko Morii, Mineko Sakoda, Norio Sugita, Masaaki Maekawa
  • Patent number: 5750250
    Abstract: Hematite particles for a non-magnetic undercoat layer for a magnetic recording medium, comprise: high-density acicular hematite particles having an average major axial diameter of not more than 0.3 .mu.m, a major axial diameter distribution in geometrical standard of not more than 1.50 and a BET specific surface area of not less than 35 m.sup.2 /g, showing a pH of not less than 8, and containing not more than 300 ppm of soluble sodium salt, calculated as Na, and not more than 150 ppm of soluble sulfate, calculated as SO.sub.4.
    Type: Grant
    Filed: October 18, 1996
    Date of Patent: May 12, 1998
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Hiroko Morii
  • Patent number: 5604015
    Abstract: The disclosure describes a non-magnetic undercoating layer for a magnetic recording medium, coated on the surface of a non-magnetic substrate comprising:non-magnetic particles selected from the group consisting of particles (1) and (2):(1) coated acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles which are produced by adhering not less than 0.01 to 20 wt % (calculated as Al, SiO.sub.2 or Al and SiO.sub.2, and based on acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material) of an oxide or a hydroxide containing Al, Si or both Al and Si to the surfaces of acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material, and have a molecular weight-dependent parameter .alpha. represented by the following formula of not less than 0.5:As=K.sub.1 .multidot.M.sup..alpha.wherein M represents the number-average molecular weight of a binder resin, As represents the saturation adsorption of said binder resin, and K.sub.
    Type: Grant
    Filed: May 10, 1994
    Date of Patent: February 18, 1997
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Minoru Ohsugi, Hiroko Morii, Mineko Sakoda, Norio Sugita, Masaaki Maekawa
  • Patent number: 5587232
    Abstract: Disclosed herein are non-magnetic particles for a non-magnetic undercoat layer of a magnetic recording medium, comprising acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles coated with at least one selected from the group consisting of an A1 compound, a silane coupling agent, a titanate coupling agent, an aluminate coupling agent and a zirconate coupling agent; a non-magnetic undercoating layer containing such non-magnetic particles; and magnetic recording medium having such an undercoating layer.
    Type: Grant
    Filed: August 4, 1993
    Date of Patent: December 24, 1996
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Minoru Ohsugi, Toshiharu Harada, Masaru Isoai, Kazushi Takama
  • Patent number: 5525649
    Abstract: Disclosed herein in are a magnetic paint composed of a kneaded composition comprising fine magnetic iron based alloy particles, acicular fine magnetic iron oxide particles or plate-like fine magnetic ferrite particles, a binder resin and an organic solvent, the solid content of the fine magnetic iron based alloy particles, the acicular fine magnetic iron oxide particles or plate-like fine magnetic ferrite particles and the binder resin in the kneaded composition being from 65 to 85% by weight, the binder resin being from 5 to 30% by weight based on the fine magnetic iron based alloy particles, the acicular fine magnetic iron oxide particles or plate-like fine magnetic ferrite particles, and a gloss at 45.degree. after dispersion for 6 hours being not less than 120% when formed into a coating film; and a method of preparing the same.
    Type: Grant
    Filed: May 17, 1995
    Date of Patent: June 11, 1996
    Assignee: Toda Kogyo Corp.
    Inventors: Akihiro Nishimura, Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Hiroko Itamochi
  • Patent number: 5469274
    Abstract: An image processing apparatus comprises an image storing device and an image inputting device, in which a parameter determining circuit compares an image input through the image inputting device with an image stored in the image storing device to calculate parameters for correction and in which the input image is corrected by a correction method different from that effected on the image having been stored, then to be combined therewith. The processing is sequentially effected on time-serially input images to produce a higher resolution image in the image storing device as compared with the input images.
    Type: Grant
    Filed: March 3, 1993
    Date of Patent: November 21, 1995
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keisuke Iwasaki, Kengo Takahama
  • Patent number: 5345544
    Abstract: A data base system has a chart generation unit for generating a chart pattern in accordance with chart data applied thereto, an indicator management unit for managing a plurality of indicators which symbolize particular functions, and attribute information associated with the indicators, and an indicator pattern generation unit for generating indicator patterns representative of the indicators in accordance with the attribute information associated with the respective indicators, which attribute information are managed by the indicator management unit.
    Type: Grant
    Filed: April 29, 1991
    Date of Patent: September 6, 1994
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keisuke Iwasaki, Masaki Takakura, Yasusuke Asayama
  • Patent number: 5285193
    Abstract: A system which includes a chart forming section for forming a pattern of a chart to be displayed on a screen, a recording section for recording, per each record, attribute information which designates a predetermined position on the chart, a display section for displaying the chart formed by the chart forming device on the screen and also for displaying a symbol at the predetermined position on the chart as designated by each attribute information, and a designating section capable of designating the record corresponding to the attribute information which indicates the position of the symbol by specifying any of the symbol on the chart displayed on the screen by the display section.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: February 8, 1994
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keisuke Iwasaki, Masaki Takakura, Yasukuni Yamane, Noritoshi Kako
  • Patent number: 5124207
    Abstract: Disclosed herein is a magnetic iron oxide particle comprising a magnetic iron oxide core particle containing ferrous iron, a Zn compound layer as a lower coating layer on the surface of said core particle, and an Si compound layer as an upper coating layer thereon.
    Type: Grant
    Filed: April 10, 1990
    Date of Patent: June 23, 1992
    Assignee: Toda Kogyo Corp.
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Hiroko Itamochi
  • Patent number: 5061570
    Abstract: A magnetic recording medium comprising a substrate, and a magnetic recording layer composed of a coating composition containing a binder resin and magnetic particles, the binder resin being a polyester having an iminosulfonyl group, is disclosed. The magnetic recording medium has excellent magnetic characteristics.
    Type: Grant
    Filed: October 9, 1990
    Date of Patent: October 29, 1991
    Assignee: Toda Kogyo Corp.
    Inventors: Akihiro Nishimura, Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Hiroko Itamochi
  • Patent number: 4992781
    Abstract: An image synthesizer of an image editing apparatus not only stores image data of two or more source images and includes a display device for displaying an image according to received image data, but also is provided with an address generator which, controlled by a data processor, transmits address signals sequentially to have a synthesized image of these source images displayed such that the individual source images appear superposed and transparent to each other. Each pixel of the display device displays only one of the source images and area densities of pixels displaying each of the source images very over the two-dimensional screen of the display device. When one of the source images is superposed on top of another, a pattern is stored in a pattern memory such that pixels displaying one of the images are scattered into the area of the other image according to the pattern such that the boundary between source images can be made controllably less conspicuous.
    Type: Grant
    Filed: July 14, 1988
    Date of Patent: February 12, 1991
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keisuke Iwasaki, Masaki Takakura, Yasukuni Yamane, Noritoshi Kako