Patents by Inventor Kiyotoshi Yamashita

Kiyotoshi Yamashita 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: 5508158
    Abstract: A silver halide photographic light sensitive material comprising a support having thereon a silver halide emulsion layer containing silver halide grains, wherein the silver halide emulsion contains silver halide tabular grains having an aspect ratio of a diameter to a thickness of less than 8 and accounting for at least 70% of the total grain projection area of the emulsion; the tabular grains having a ratio (t/l) of the thickness (t) to the longest distance (l) between two or more parallel twin planes of the tabular grain of not less than 5; total surface of the tabular grain consisting of two parallel principal plane faces and side-faces, and all of the parallel principal plane faces and 90% or less of side-faces are a (111) face.
    Type: Grant
    Filed: March 7, 1994
    Date of Patent: April 16, 1996
    Assignee: Konica Corporation
    Inventors: Kiyotoshi Yamashita, Shu Nishiwaki, Yasuo Honda
  • Patent number: 4833069
    Abstract: A silver halide color photographic light-sensitive material is disclosed. The material is improved in a developing stability, whose red density-green density balance is hardly affected even by change in a developing condition. The photographic material comprises a support and, provided on a side of the support, at least one red-sensitive silver halide emulsion layer and at least one green-sensitive silver halide emulsion layer. The total thickness of the layers provided on the emulsion coated side of the suport, is within the range of from 5 to 18 .mu.m. The red-sensitive emulsion layer contains a cyan-dye forming coupler and a clored cyan-dye forming coupler, and a ratio of the colored cyan-dye forming coupler to the total amount of the cyan-dye forming coupler and the colored cyan-dye forming coupler is within the range of from 15 to 80 mol %.
    Type: Grant
    Filed: January 20, 1987
    Date of Patent: May 23, 1989
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Fumio Hamada, Yoshitaka Yamada, Kiyotoshi Yamashita
  • Patent number: 4554247
    Abstract: A silver halide photographic material having as essential photographic layers at least one photosensitive silver halide emulsion layer and at least one non-sensitive hydrophilic colloidal layer on a support is disclosed. At least one of said photographic layers contains fine oil globules at a density of 1 or more, and a hardener having at least three functional groups is incorporated in at least one photographic layer containing said fine oil globules and/or at least one photographic layer which is farther from said support than the photographic layer containing said fine oil globules.
    Type: Grant
    Filed: February 13, 1984
    Date of Patent: November 19, 1985
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Kiyotoshi Yamashita, Minoru Ishikawa, Hideo Ohta, Kenji Kumashiro
  • Patent number: 4499179
    Abstract: A silver halide photographic light-sensitive element having on a support, at least one silver halide light-sensitive emulsion layer which has thereon a protective layer composed of a binder containing a non-light-sensitive hydrophilic colloid. The protective layer is made up of an outer layer and an inner layer. The outer layer contains oil particles in the form of water-insoluble liquid droplets finely dispersed in the binder and the inner layer contains fine solid particles wherein the ratio of the thickness of the inner layer to the outer layer is at least 1.5.
    Type: Grant
    Filed: February 22, 1983
    Date of Patent: February 12, 1985
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Hideo Ota, Kiyotoshi Yamashita
  • Patent number: 4490460
    Abstract: A silver halide color photographic material in which the photographic characteristics do not deteriorate when contacted with formaldehyde.
    Type: Grant
    Filed: March 3, 1983
    Date of Patent: December 25, 1984
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Satoru Shimba, Yoshikazu Watanabe, Kazuo Kato, Kiyotoshi Yamashita