Patents by Inventor Tateshi Iytaka

Tateshi Iytaka 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).

  • Method of processing of light-sensitive silver halide photographic material
    Patent number: 4268620
    Abstract: A light-sensitive silver halide photographic material containing a tetrazolium compound, is treated with a developing solution containing no hydroquinone developing agent, which material comprises a support and a silver halide emulsion layer coated thereon, containing silver halide grains having an average grain size of 0.05 to 1.5.mu., at least 75% of said grains being within a range of 0.6 to 1.4 times the said average grain size and a sensitizing dye.
    Type: Grant
    Filed: January 16, 1978
    Date of Patent: May 19, 1981
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Tateshi Iytaka, Syunji Matsuo, Toshio Nagatani, Kazuo Takahashi, Takeshi Habu
  • Light-sensitive silver halide photographic materials
    Patent number: 4221864
    Abstract: Light-sensitive silver halide photographic materials which comprise a support, a hydrophilic colloidal layer coated thereon which contains a silver halide emulsion layer and tetrazolium compounds, said silver halide emulsion layer containing a combination of two types of specific sensitizing dyes.
    Type: Grant
    Filed: April 30, 1979
    Date of Patent: September 9, 1980
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Tateshi Iytaka, Syunji Matsuo, Toshio Nagatani, Kazuo Takahashi, Takeshi Habu
  • Process for forming high-contrast silver images
    Patent number: 4169733
    Abstract: Process for forming high-contrast silver images which comprises treating a light-sensitive silver halide photographic material provided with a hydrophilic colloidal layer containing a silver halide emulsion layer coated on a support and containing a tetrazolium compound, after imagewise exposure, with a developer and/or a processing solution prior to the developing, both of which contains at least a nitrogen-containing heterocyclic compound substituted with at least mercapto, thioketone or thioether group.
    Type: Grant
    Filed: January 23, 1978
    Date of Patent: October 2, 1979
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Tateshi Iytaka, Syunji Matsuo, Toshio Nagatani, Kazuo Takahashi, Takeshi Habu