Patents by Inventor Nobuyoshi Sekikawa

Nobuyoshi Sekikawa 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: 5198335
    Abstract: An integral multilayer analytical element for the analysis of an ammonia-forming substrate comprising:(I) a light-transmissive, liquid-impermeable support:(II) an ammonia indicator layer containing a reagent capable of undergoing a detectable change by gaseous ammonia;(III) a liquid barrier layer which allows gaseous ammonia passing therethrough;(IV) an ammonia-forming substrate reaction layer containing a reagent capable of reacting with an ammonia-forming substrate to form gaseous ammonia;(V) an intrinsic ammonia trapping layer containing a reagent which acts on intrinsic ammonia to convert it into a form which can not reach said reaction layer; and(IV) a porous spreading layer, in a laminate form.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: March 30, 1993
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobuyoshi Sekikawa, Harumi Katsuyama, Asaji Kondo
  • Patent number: 4548906
    Abstract: An integral multilayer analytical element for the analysis of ammonia or an ammonia forming substrate in a liquid sample is disclosed. The element comprises a transparent support on which an indicator layer for ammonia, a liquid blocking layer, a reagent layer incorporated with a reagent which may react with the substrate to form ammonia, and a spreading layer, are integrally superposed in this order. The improvement is that the liquid blocking layer is made of a porous material which is permeable to ammonia but substantially impermeable to liquids.
    Type: Grant
    Filed: May 11, 1984
    Date of Patent: October 22, 1985
    Assignee: Fuji Shashin Film Kabushiki Kaisha
    Inventors: Nobuyoshi Sekikawa, Harumi Katsuyama, Asaji Kondo
  • Patent number: 4411700
    Abstract: A desensitizer composition containing an imidazole derivative shown by the following general formula (I) ##STR1## wherein R.sub.1 is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms; R.sub.2 is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an amino group, or an alkylthio group having 1 to 20 carbon atoms; R.sub.3 and R.sub.4 each is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 20 carbon atoms; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each may be substituted, can be effectively used for partially desensitizing a developer sheet of pressure-sensitive copying papers, particularly where diphenylamine series color formers are used.
    Type: Grant
    Filed: October 16, 1981
    Date of Patent: October 25, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobuyoshi Sekikawa, Ken Iwakura, Akio Miyamoto, Masato Satomura
  • Patent number: 4411699
    Abstract: A desensitizer composition containing the amidine derivative shown by following general formula can be effectively used for partially desensitizing a developer sheet of pressure-sensitive copying papers using diphenylamine series color formers: ##STR1## wherein R.sub.1 is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms; R.sub.2 is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an amino group, or an alkylthio group having 1 to 20 carbon atoms; and n is an integer of 2 to 6; said R.sub.1 and R.sub.2 may have a substituent and when both R.sub.1 and R.sub.2 are an alkyl group, at least one of R.sub.1 and R.sub.2 is an alkyl group having a substituent.
    Type: Grant
    Filed: October 16, 1981
    Date of Patent: October 25, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Ken Iwakura, Nobuyoshi Sekikawa, Akio Miyamoto
  • Patent number: 4401717
    Abstract: A heat-sensitive recording material comprising a base and one or more heat-sensitive color-forming layers containing an electron donating colorless dye and an electron accepting organic compound is disclosed, wherein at least one of said color-forming layers contains a urea derivative having a least 7 carbon atoms or a urethane derivative having at least 8 carbon atoms.
    Type: Grant
    Filed: November 23, 1981
    Date of Patent: August 30, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Teppei Ikeda, Sadao Ishige, Nobuyoshi Sekikawa, Akira Igarashi, Takekatsu Sugiyama
  • Patent number: 4181530
    Abstract: A thermally developable light-sensitive material wherein heat fog is prevented comprising a support having therein or in one or more layers thereon (a) an organic silver salt, (b) a photo catalyst and (c) a reducing agent and containing (d) a phthalimide having at least one electron-attracting substituent, such as a halogen atom or an acyl group.
    Type: Grant
    Filed: July 14, 1978
    Date of Patent: January 1, 1980
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shinpei Ikenoue, Nobuyoshi Sekikawa, Takao Masuda
  • 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: 4152160
    Abstract: A thermally developable light-sensitive material with improved storage stability and a minimized thermal fog without an increase in both light discoloration and dark discoloration which comprises a support and having therein or in at least one layer thereon at least (a) an organic carboxylic acid silver salt comprising about 50 mol% or more of silver behenate, (b) a photocatalyst and (c) a reducing agent, and with the material containing (d) at least one compound (1) represented by the following general formula (I): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3, which may be the same or different, each represents a hydrogen atom or a substituent selected from the group consisting of a nitro group, a cyano group and a halogen atom, with the proviso that R.sub.1, R.sub.2 and R.sub.3 are not all simultaneously a hydrogen atom, and (2) having a half-neutralization point of from about 40 mV to about 140 mV above the half-neutralization point of benzoic acid in isopropanol.
    Type: Grant
    Filed: April 5, 1978
    Date of Patent: May 1, 1979
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shinpei Ikienoue, Takao Masuda, Nobuyoshi Sekikawa
  • Patent number: 4144072
    Abstract: A thermally developable light-sensitive material containing at least (a) an organic silver salt, (b) a photocatalyst and (c) a reducing agent in a support and/or in one or more layers thereon and, additionally containing (d) at least one phthalazinone, and (e) at least one phthalimide, having improved shelf life particularly at high humidity, providing pure black tone images, and further providing a high speed upon heat development.
    Type: Grant
    Filed: October 25, 1977
    Date of Patent: March 13, 1979
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shinpei Ikenoue, Takao Masuda, Nobuyoshi Sekikawa
  • Patent number: 4140532
    Abstract: A thermally developable light-sensitive material comprising a support and containing at least (a) an organic silver salt, (b) a photocatalyst, (c) a reducing agent and (d) a color toning agent in the support or in at least one layer provided on the support, wherein the color toning agent is at least one 2H-1,3-benzothiazin-2,4(3H)-dione, e.g., having the following general formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.
    Type: Grant
    Filed: December 14, 1977
    Date of Patent: February 20, 1979
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hideo Sato, Nobuyoshi Sekikawa, Toshinao Ukai, Takao Masuda
  • Patent number: 4096143
    Abstract: 1-PHTHALAZINONE AND 1-PHTHALAZINONE DERIVATIVES OF THE FOLLOWING FORMULA: ##STR1## wherein R.sup.1 represents a hydrogen atom, an alkyl group, an aralkyl group, an acyloxyl group, an alkoxyl group, a halogen atom, a nitro group, an amino group or an amido group; and R.sup.2 represents a hydrogen atom, an alkyl group or an aryl group. Such can be prepared at good yields by the reaction of a benzoic acid derivative of the following formula: ##STR2## wherein R.sup.1 has the same meanings as defined above; X represents a halogen atom; and Y represents a hydroxyl group, an alkoxyl group or a halogen atom; with hydrazine or a hydrazine derivative of the following formula:R.sup.2 -- NH -- NH.sub.2 (III)wherein R.sup.2 has the same meanings as defined above.
    Type: Grant
    Filed: July 21, 1976
    Date of Patent: June 20, 1978
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hideo Sato, Seiji Horie, Nobuyoshi Sekikawa, Hisatake Ono
  • Patent number: 4076534
    Abstract: A heat developable light-sensitive material comprising a support having thereon at least one light-sensitive layer containing (1) an oxidation-reduction image-forming combination of (a) a silver salt oxidizing agent and (b) a reducing agent and (2) a catalytic amount of a light-sensitive silver halide or a compound capable of reacting with the silver salt (a) to form a light-sensitive silver halide, the light-sensitive layer further containing (3) at least one specific phthalazinone compound. The development of the above light-sensitive material is carried out simply by heating the material at a temperature of about 90.degree. to 180.degree. C. for 1 to 60 seconds after imagewise exposure. An image of black tone can be obtained without contaminating the developing machine.
    Type: Grant
    Filed: July 26, 1976
    Date of Patent: February 28, 1978
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yasuhiro Noguchi, Nobuyoshi Sekikawa, Kenji Sashihara, Takao Masuda
  • Patent number: 4030930
    Abstract: A heat-developable light-sensitive material comprising a support having thereon at least one layer containing (a) an organic silver salt oxidizing agent; (b) a catalytic amount of a light-sensitive silver halide or a compound capable of forming a light-sensitive silver halide through reaction with the organic silver salt component (a); (c) a reducing agent; and (d) at least one compound represented by the following general formulae (I) to (III) ##STR1## in which A and B each represents different substituents selected from the group consisting of an amino group and a --OX group; X represents a hydrogen atom, an alkali metal atom, a silver atom, a mercury atom or a gold atom; R.sub.1 and R.sub.2 each represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aralkyl group, an allyl group, an acyl group, an aryl group or an aryloxy group; and R.sub.3, R.sub.4 and R.sub.5 each represents a hydrogen atom, a halogen atom or an alkyl group.
    Type: Grant
    Filed: February 18, 1975
    Date of Patent: June 21, 1977
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kenji Sashihara, Takao Masuda, Yasuhiro Noguchi, Nobuyoshi Sekikawa, Tadao Shishido
  • Patent number: 4009039
    Abstract: A heat developable light-sensitive element having reduced thermal fogging and improved light stability comprising a support having therein or in one or more layers thereon (a) an organic silver salt, (b) a light-sensitive silver halide or a compound capable of forming a light-sensitive silver halide upon reaction with the organic silver salt, (c) a reducing agent, and (d) an oxazolinone compound.
    Type: Grant
    Filed: August 18, 1975
    Date of Patent: February 22, 1977
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takao Masuda, Nobuyoshi Sekikawa
  • Patent number: 4006021
    Abstract: Two components consisting of an organic halogen compound generating halogen containing free-radicals and/or halogen ions due to the action of radiation and a color generator reacting with the thus generated halogen containing free-radicals and/or halogen ions to form a visible image are subjected to dispersion in the form of discrete globules in a hydrophilic binder, and the thus dispersed mixture is applied on a suitable support to thereby obtain a recording material. The entire surface of the thus obtained recording material is heated prior to the action of the radiation forming the visible color image in a dry treatment. The described process is suitable for image formation by negative-positive working photographic procedures.
    Type: Grant
    Filed: April 14, 1975
    Date of Patent: February 1, 1977
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroshi Yamashita, Nobuyoshi Sekikawa, Hisatake Ono
  • Patent number: 4003749
    Abstract: A heat-developable light-sensitive material comprising a support having therein or in one or more layers thereon an organic silver (b) a light-sensitive silver halide, and (c) a reducing agent, with the light-sensitive silver halide comprising the reaction product of a part of the organic silver salt and an N-halo compound represented by the following formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each is a hydrogen atom; an alkyl group having 1 to 22 carbon atoms; a haloalkyl group having 1 to 22 carbon atoms; an amino group; a hydroxyalkyl group having 1 to 22 carbon atoms; an allyl group; a naphthyl group; a benzyl group; a ##STR2## group in which R.sub.5 is a hydrogen atom, a halogen atom, an alkyl group, an alkylthio group, an amino group or an alkylamino group; a benzyloxy group; an aryl group; a haloaryl group; an alkylaryl group; and alkoxyaryl group; an --OR.sub.6 group in which R.sub.
    Type: Grant
    Filed: July 15, 1975
    Date of Patent: January 18, 1977
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takao Masuda, Nobuyoshi Sekikawa