Patents by Inventor Nobuo Sakai

Nobuo Sakai 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: 4241164
    Abstract: A silver halide photographic material providing very high contrast and negative image photographic characteristics comprising a support having thereon at least one silver halide photographic emulsion layer containing substantially surface latent image type mono-dispersed silver halide grains and providing a negative image, at least one hydrophilic colloid layer of the photographic material containing a compound represented by the general formula (I)R.sup.1 NHNHCOR.sup.2 (I)wherein R.sup.1 represents an aryl group and R.sup.2 represents a hydrogen atom, a phenyl group, or an unsubstituted alkyl group having 1 to 3 carbon atoms; and a compound represented by the general formula (II) or (III) ##STR1## wherein R.sup.3, R.sup.4, R.sup.5 and R.sup.
    Type: Grant
    Filed: October 10, 1978
    Date of Patent: December 23, 1980
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroyuki Mifune, Shunji Takada, Yoshitaka Akimura, Nobuo Sakai
  • Patent number: 4170480
    Abstract: A thermally developable light-sensitive material comprising a support having therein or in at least one layer thereon (a) an organic silver salt, (b) a photocatalyst, and (c) a reducing agent, and additionally (d) at least one 1,2,4-triazole compound.
    Type: Grant
    Filed: September 7, 1977
    Date of Patent: October 9, 1979
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shinpei Ikenoue, Takao Masuda, Harumi Katsuyama, Nobuyoshi Sekikawa, Tadao Shishido, Nobuo Sakai
  • Patent number: 4144068
    Abstract: In a method of processing an image-wise exposed silver halide color photographic material by applying thereto at least a color development processing and a silver removal processing (including performing a bleaching and a fixing separately or simultaneously, (e.g., a blixing)), the improvement which comprises processing, after the color development processing, the silver halide color photographic material with a processing bath containing a compound, as a bleach accelerator, represented by the following general formula (I): ##STR1## wherein R represents an --NR.sup.4 R.sup.5 group, an --O--R.sup.6 group or an --S--R.sup.6 group; R.sup.6 represents an atomic group necessary for forming a ring together with R.sup.1 ; R.sup.1, R.sup.4 and R.sup.5, which may be the same or different, each represents a hydrogen atom or an alkyl group; R.sup.2 and R.sup.
    Type: Grant
    Filed: January 30, 1978
    Date of Patent: March 13, 1979
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroshi Ishibashi, Nobuo Sakai, Kiyoshi Imai, Junya Nakajima
  • Patent number: 4076533
    Abstract: A two-equivalent color photographic coupler having advantageous properties and capable of forming a magenta color image upon coupling with an oxidation product of an aromatic primary amine developing agent, in which the carbon atom at the coupling position of the coupler is bonded to the nitrogen atom at the 1- or 4-position of a 1,2,4-triazole ring; a color photographic light-sensitive material containing the above-mentioned color photographic coupler and a method of forming a color image comprising developing an image-wise exposed photographic light-sensitive material in the presence of the above-described color photographic coupler are also described.
    Type: Grant
    Filed: November 10, 1976
    Date of Patent: February 28, 1978
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Satoshi Ota, Kotaro Nakamura, Nobuo Sakai, Nobuo Furutachi, Yukio Yokota