Patents by Inventor Tadashi Umehara

Tadashi Umehara 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: 5665502
    Abstract: An electrophotographic photoreceptor comprising a cylindrical electrically conductive substrate having thereon at least a photoconductive layer, the conductive substrate having a marking portion in which the light reflectance of the surface of the conductor substrate has been changed by a laser light treatment, a method for producing the photoreceptor, and an image correcting method using the photoreceptor.
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: September 9, 1997
    Assignees: Mitsubhishi Kasei Corporation, Sharp Kabushiki Kaisha
    Inventors: Kunio Ohashi, Mitsuru Tokuyama, Hiroshi Kinashi, Mamoru Nozomi, Tadashi Umehara, Toshiya Asari
  • Patent number: 5536607
    Abstract: An electrophotographic photoreceptor comprising a cylindrical electrically conductive substrate having thereon at least a photoconductive layer, the conductive substrate having a marking portion in which the light reflectance of the surface of the conductor substrate has been changed by a laser light treatment, a method for producing the photoreceptor, and an image correcting method using the photoreceptor.
    Type: Grant
    Filed: November 5, 1993
    Date of Patent: July 16, 1996
    Assignees: Mitsubishi Kasei Corporation, Sharp Kabushiki Kaisha
    Inventors: Kunio Ohashi, Mitsuru Tokuyama, Hiroshi Kinashi, Mamoru Nozomi, Tadashi Umehara, Toshiya Asari
  • Patent number: 5292607
    Abstract: A novel electrophotographic photoreceptor and a method of preparation therof are disclosed. The photoreceptor is characterized in that the photosensitive layer contain a specific carbonate resin binder resin having a weight average molecular weight on not less than 200,000. The resin is preferably a polycarbonate resin which contains repeating units represented by the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are respectively and independently a hydrogen atom, a lower alkyl group, a halogen atom or an unsubstituted or substituted aromatic group; and R.sup.9 and R.sup.10 are respectively and independently a hydrogen atom, a lower alkyl group, an unsubstituted or substituted aromatic group, or form a ring or a carbonyl group together with the linking carbon atom.
    Type: Grant
    Filed: October 22, 1992
    Date of Patent: March 8, 1994
    Assignee: Mitsubishi Kasei Corporation
    Inventors: Ryoko Aso, Michio Kawai, Osamu Murakami, Mamoru Nozomi, Ryuji Nakayama, Tadashi Umehara
  • Patent number: 4972569
    Abstract: A method of rotating and transferring hollow cylindrical workpieces without causing the outer surfaces of such workpieces to come into contact with each other and a non-contact method of coating hollow cylindrical workpieces which are rotated and transferred, characterized in that flanges having bores in the central portions thereof are fitted over both end portions of each hollow cylindrical workpiece, a shaft being inserted through the bores in these flanges and supported horizontally together with the workpiece at each end on and rotated by a plurality of paired vertically movable rollers which are spaced by a distance not shorter than the length of the workpiece, a pusher for moving the workpiece being provided on a shaft, a coating mechanism being provided at an intermediate portion of the shaft in order to coat the workpiece with a material, a plurality of flanged workpieces being moved by the pusher toward a discharge end of the shaft and removed therefrom in order.
    Type: Grant
    Filed: August 14, 1989
    Date of Patent: November 27, 1990
    Assignee: Mitsubishi Kasei Corporation
    Inventors: Motohisa Aoki, Ryuuji Nakayama, Tadashi Umehara, Jiro Taguti