Patents by Inventor Kiyoshi Suematsu

Kiyoshi Suematsu 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: 5766833
    Abstract: An image-forming process developing a previously image-exposed silver halide photographic material with an alkaline developer containing a reductone compound as a main developing agent in the presence of a 1,2,5-thiadiazole compound and/or a 2,1,3-benzothiadiazole compound, and the silver halide photographic material and the photographic developer being used for the process are disclosed. In this case, the 1,2,5-thuiadiazole compound and/or the 2,1,3-benzothiadiazole may be contained in the silver halide photographic material and/or the alkaline developer. Super high-contrast images for photomechanical process having a gamma of higher than 15 and having no pepper and less fog can be obtained.
    Type: Grant
    Filed: July 8, 1997
    Date of Patent: June 16, 1998
    Assignee: Dainippon Ink and Chemicals Inc.
    Inventors: Kiyoshi Suematsu, Hiroaki Muratake, Haruhiko Kaji, Naoki Obi, Yasuhiko Kojima, Yasuo Shigemitsu
  • Patent number: 5683854
    Abstract: An image-forming process developing a previously image-exposed silver halide photographic material with an alkaline developer containing a reductone compound as a main developing agent in the presence of a 1,2,5-thiadiazole compound and/or a 2,1,3-benzothiadiazole compound, and the silver halide photographic material and the photographic developer being used for the process are disclosed. In this case, the 1,2,5-thuiadiazole compound and/or the 2,1,3-benzothiadiazole may be contained in the silver halide photographic material and/or the alkaline developer. Super high-contrast images for photomechanical process having a gamma of higher than 15 and having no pepper and less fog can be obtained.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: November 4, 1997
    Assignee: Dainippon Ink and Chemicals Inc.
    Inventors: Kiyoshi Suematsu, Hiroaki Muratake, Haruhiko Kaji, Naoki Obi, Yasuhiko Kojima, Yasuo Shigemitsu
  • Patent number: 5460919
    Abstract: A process of forming a super high-contrast negative image is disclosed, which comprises the steps of imagewise exposing a negative-working silver halide photographic material comprising a support having thereon one or more hydrophilic colloidal layers, at least one of the one or more hydrophilic colloidal layers being a negative-working silver halide emulsion layer, and then developing the photographic material with a developer containing an aminophenol derivative developing agent and a reductone compound in the existence of an organic compound having a negative reduction potential. A negative-working silver halide photographic material and a photographic developer being used for the image-forming process are also disclosed.
    Type: Grant
    Filed: July 22, 1994
    Date of Patent: October 24, 1995
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Naoki Obi, Yasuhiko Kojima, Yasuo Shigemitsu, Jun Takeuchi, Kiyoshi Suematsu
  • Patent number: 5372911
    Abstract: A process of forming a super high-contrast negative image is disclosed, which comprises the steps of imagewise exposing a negative-working silver halide photographic material comprising a support having thereon one or more hydrophilic colloidal layers, at least one of the one or more hydrophilic colloidal layers being a negative-working silver halide emulsion layer, and then developing the photographic material with a developer containing an aminophenol derivative developing agent and a reductone compound in the existence of an organic compound having a negative reduction potential. A negative-working silver halide photographic material and a photographic developer being used for the image-forming process are also disclosed.
    Type: Grant
    Filed: June 11, 1992
    Date of Patent: December 13, 1994
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Naoki Obi, Yasuhiko Kojima, Yasuo Shigemitsu, Jun Takeuchi, Kiyoshi Suematsu
  • Patent number: 5362621
    Abstract: A direct positive silver halide photographic material and a method for forming a high contrast image using the same are disclosed, in which a pre-fogged direct positive silver halide emulsion layer contains a salt of a nitrogen-containing compound having at least one pyridine nucleus and at least one pyridinium nucleus. The photographic material, after imagewise exposure, is developed with an alkaline developer containing a developing agent, preferably a reductance compound. The photographic material provides high contrast characteristics having a gamma exceeding 10.
    Type: Grant
    Filed: August 18, 1993
    Date of Patent: November 8, 1994
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Naoki Obi, Kiyoshi Suematsu, Yasuhiko Kojima, Masatoshi Katayama, Yasuo Shigemitsu
  • Patent number: 5284733
    Abstract: A silver halide photographic material is disclosed. The photographic material comprises a support having coated thereon one or more hydrophilic colloidal layers, at least one of the hydrophilic colloidal layers being a negative working silver halide emulsion layer, wherein said silver halide emulsion layer or another hydrophilic colloidal layer contains a water-soluble polymer or copolymer having a quaternary ammonium salt in a repeating unit. The process for forming a high contrast negative image using the photographic material is also disclosed.
    Type: Grant
    Filed: October 1, 1991
    Date of Patent: February 8, 1994
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Yasuhiko Kojima, Naoki Obi, Yasuo Shigemitsu, Kiyoshi Suematsu