Patents by Inventor Takatoshi Ishikawa

Takatoshi Ishikawa 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: 4751518
    Abstract: Disclosed is a heating resistor composed of tungsten of 35-45 at. %, aluminum of 25-35 at. %, nitrogen of 10-20 at. %, and oxygen of 5-20 at. %, and a thermal head comprising a heating resistor layer composed of tungsten of 35-45 at. %, aluminum of 25-35 at. %, nitrogen of 10-20 at. %, and oxygen of 5-20 at. %.
    Type: Grant
    Filed: June 27, 1986
    Date of Patent: June 14, 1988
    Assignee: Alps Electric Co., Ltd.
    Inventors: Takatoshi Ishikawa, Masakazu Kato
  • Patent number: 4742361
    Abstract: Disclosed is a thermal head in which a heat-generating resistor layer, a power feeding conductor layer, and a protecting film are formed on an electrically insulating substrate, the heat generating resistor layer being constituted by an alloy of tantalum, rare earth metals, and nitrogen.Further disclosed is a method of producing a thermal head comprising the steps of forming a heat-generating resistor layer, a power feeding conductor layer, and a protecting film, on an electrically insulating substrate, the step of forming the heat-generating resistor layer including the step of performing spattering in mixed gases of argon and nitride to form the heat-generating resistor layer made of an alloy of tantalum, a rare earth metal material, and nitrogen, by using a composite target in which small pieces of the rare earth metal materials are disposed on a tantalum target.
    Type: Grant
    Filed: February 7, 1986
    Date of Patent: May 3, 1988
    Assignee: Alps Electric Co., Ltd.
    Inventors: Takatoshi Ishikawa, Masakazu Kato, Takehiro Takoshima, Yoshimi Kamijyo
  • Patent number: 4695530
    Abstract: A method for forming an image in a silver halide color photographic light-sensitive material comprising developing an imagewise exposed silver halide color photographic light-sensitive material and then bleach fixing the silver halide color photographic light-sensitive material in a bleach fixing bath, the silver halide photographic color light sensitive material comprising a support having thereon a silver halide emulsion layer containing a yellow coupler, a silver halide emulsion layer containing a magenta coupler and a silver halide emulsion layer containing a cyan layer, wherein the silver halide emulsion layer containing the magneta coupler contains at least one kind of pyrazoloazole type coupler represented by the general formula (I): ##STR1## wherein R.sup.
    Type: Grant
    Filed: April 23, 1986
    Date of Patent: September 22, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kotaro Nakamura, Takatoshi Ishikawa
  • Patent number: 4681835
    Abstract: A method of processing a silver halide color photographic material, which comprises processing a photographic material containing at least one pyrazoloazole type magenta coupler represented by the general formula (I) in a final bath containing a soluble iron salt in an amount of at least 1.times.10.sup.-4 mol/l, whereby marked improvements in stabilization of color images, especially cyan dye images and prevention of yellow stain are achieved: ##STR1## wherein R.sub.1 represents a hydrogen atom or a substituent, X represents a hydrogen atom or a group capable of being eliminated by the coupling reaction with an oxidation product of an aromatic primary amine developing agent, and Z.sub.a, Z.sub.b and Z.sub.c each represents methine group, a substituted methine group, .dbd.N-- or --NH--, provided that one of the Z.sub.a -Z.sub.b and Z.sub.b -Z.sub.c bonds is a double bond and the other is a single bond, in which when it represents a double bond the Z.sub.b -Z.sub.
    Type: Grant
    Filed: December 12, 1985
    Date of Patent: July 21, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Kiyoshi Nakazyo
  • Patent number: 4588677
    Abstract: A method for processing a silver halide color photosensitive material which comprises processing a silver halide color photosensitive material containing at least one 4-mercapto-5-pyrazolone type magenta coupler represented by formula (I) ##STR1## wherein W represents an aryl group; X represents an alkyl group, an aryl group or a heterocyclic ring group; and Y represents an acylamino group, a ureido group, or an anilino group; with a color developer containing at least one compound selected from a compound represented by formula (II) ##STR2## wherein R represents a lower alkyl group, and M.sub.1 and M.sub.2, which can be the same or different, each represents a hydrogen atom, and an alkali metal atom, or an ammonium group; a compound represented by formula (III) ##STR3## wherein M.sub.3, M.sub.4, M.sub.5, M.sub.6 and M.sub.
    Type: Grant
    Filed: December 28, 1984
    Date of Patent: May 13, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Junya Nakajima
  • Patent number: 4543322
    Abstract: A process for processing a color photographic silver halide light-sensitive material comprising processing the color photographic silver halide light-sensitive material with a color developer containing at least one compound represented by the general formula (I): ##STR1## wherein X is a hydrogen atom, an alkali metal atom, an ammonium group, an alkyl group, or an aryl group; Y is a substituent on the phenyl group and is a halogen atom, an alkyl group, an alkoxy group, an amino group, a hydroxyl group, a nitro group, a sulfonic acid group or a carboxylic acid group; and n is 0, 1, 2, 3 or 4. Color developers containing the compounds of the general formula (I) have greatly increased stability and thus even after long-term storage, can be used to produce developed materials having superior photographic properties.
    Type: Grant
    Filed: March 30, 1984
    Date of Patent: September 24, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Junya Nakajima
  • Patent number: 4542091
    Abstract: A process for forming color images, and a silver halide color photographic material for use in the process, are described, said process comprising processing with a developer containing hydroxylamine a silver halide color photographic material comprising a support having thereon at least one red-sensitive silver halide emulsion layer, at least one green-sensitive silver halide emulsion layer, and at least one blue-sensitive silver halide emulsion layer, said blue-sensitive silver halide emulsion layer being disposed at a more upper portion than other color-sensitive silver halide emulsion layers, and said color photographic material further comprising (1) a light-insensitive layer containing at least one of a yellow colored magenta-dye-forming coupler and a yellow non-diffusible organic dye between the lowermost blue-sensitive silver halide emulsion layer and the uppermost layer of the other color-sensitive silver halide emulsion layers, and (2) a light-insensitive silver halide emulsion in any layer above sa
    Type: Grant
    Filed: December 14, 1984
    Date of Patent: September 17, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Noboru Sasaki, Takatoshi Ishikawa, Keiichi Adachi
  • Patent number: 4504577
    Abstract: A silver halide photographic material is disclosed which is comprised of a support having formed thereon a light-sensitive silver halide layer and a particular compound represented by the general formulae (I), (II) and (III). The compound is utilized in the photographic material in order to prevent the occurrence of contaminations which are caused by metals intermixed in the silver halide photographic materials during production, packaging, preservation and/or processing. The presence of such compounds also prevents the deterioration of photographic materials caused by metal ions existing in processing solutions and aids in preventing the reduction in the uniformity of processing.
    Type: Grant
    Filed: February 27, 1984
    Date of Patent: March 12, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshinobu Yoshida, Nobuo Sakai, Takatoshi Ishikawa
  • Patent number: 4493888
    Abstract: A silver halide photographic light-sensitive material containing a diffusion resistant coupler, a light-sensitive silver halide and at least one organic metal complex represented by the following general formula (I) in the same layer or different layers on a support. ##STR1## wherein M represents a divalent metal atom; R.sup.1 and R.sup.2, which may be the same or different, each represents an alkyl group having from 1 to 5 carbon atoms, a hydroxyalkyl group having from 1 to 5 carbon atoms, an alkoxyalkyl group having from 2 to 10 carbon atoms or an alkylsulfonamidoalkyl group having from 2 to 10 carbon atoms, or R.sup.1 and R.sup.2 may be bonded each other to form a heterocyclic ring together with the nitrogen atom; R.sup.3, represents a hydrogen atom, an alkyl group having from 1 to 5 carbon atoms or an alkoxy group having from 1 to 5 carbon atoms; and R.sup.4 and R.sup.
    Type: Grant
    Filed: July 15, 1983
    Date of Patent: January 15, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Katsusuke Endo, Eiichi Kato, Nobutaka Ohki, Takatoshi Ishikawa
  • Patent number: 4491630
    Abstract: A silver halide color photographic light-sensitive material comprising a support having thereon a silver halide emulsion layer containing at least one kind of compound represented by the following general formula (I): ##STR1## wherein each substituent represented by R.sub.1, R.sub.2, R.sub.3, X, or Ar and m are defined within the specification, said silver halide color photographic light-sensitive material comprises a compound represented by the following general formula (II) in the silver halide emulsion layer containing the compound represented by the above general formula (I) and/or a hydrophilic colloid layer which is positioned at the remoter side than the silver halide emulsion layer from the support: ##STR2## wherein each substituent represented by Y, R.sub.4, R.sub.5, R.sub.6, R.sub.7 or Ar is defined within the specification.
    Type: Grant
    Filed: January 24, 1983
    Date of Patent: January 1, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Akio Mitsui, Masakazu Morigaki, Takashi Nakamura
  • Patent number: 4486677
    Abstract: In an encased electric motor within a casing, an electrically insulating varnish is applied by vacuum impregnation to the inside surfaces of the casing and to the outer surface of the stator of the motor. The remaining empty space within the casing is filled with a heat conducting gas mixture comprising approximately 60-90% by volume of helium, with the remaining percentage being an electrically insulating gas having better electrically insulating properties than helium, such as sulphur hexafluoride. This encased motor is much lighter than conventional encased motors in which the stator enclosure is filled with a heat conducting resin potting compound and avoids warping damage which frequently occurs in conventional encased motors due to thermal expansion of the heat conducting resin potting compound.
    Type: Grant
    Filed: May 2, 1983
    Date of Patent: December 4, 1984
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Sakuei Yamamoto, Hiroshi Inao, Kiyonori Tokumitsu, Mitsuhiro Nishida, Takatoshi Ishikawa, Shigekazu Sakabe
  • Patent number: 4473635
    Abstract: A silver halide photographic light-sensitive material containing a diffusion resistant coupler, a light-sensitive silver halide and at least one compound represented by the following general formula (I) in the same layer or different layers on a support. ##STR1## Wherein R.sub.1 and R.sub.2, which may be the same or different, each represents a hydrogen atom or an alkyl group having from 1 to 10 carbon atoms, or R.sub.1 and R.sub.2 may be bonded to each other to form a heterocyclic ring together with the nitrogen atom; R.sub.3, R.sub.4, R.sub.5 and R.sub.6, which may be the same or different, each represents a hydrogen atom, a halogen atom, a hydroxy group, an amino group, an alkoxy group, an acylamido group, a sulfonamido group, an alkylsulfonamido group or an alkyl group, or R.sub.1 and R.sub.6 or R.sub.2 and R.sub.3 may be bonded to each other to form a 5-membered or 6-membered ring; X represents HPF.sub.6 or HBF.sub.4 ; and n represents an integer from 1 to 3.
    Type: Grant
    Filed: May 18, 1983
    Date of Patent: September 25, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Katsusuke Endo, Sigeru Kuwazima, Eiichi Kato, Nobutaka Ohki
  • Patent number: 4469781
    Abstract: The disclosed invention is a means for preventing the reduction of color density caused by the formation of leuco compounds from cyan dyes when processing color photographic materials with a bleach solution or a blix solution containing benzyl alcohol. The invention involves incorporating the compound shown by the following formula (I) in the bleach solution or blix solution: ##STR1## wherein X represents a hydrogen atom or an acetyl group; R represents an aryl group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be the same or different, each represents a hydrogen atom, an alkyl group or an aryl group.
    Type: Grant
    Filed: November 1, 1982
    Date of Patent: September 4, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Takashi Nakamura
  • Patent number: 4465762
    Abstract: A method for forming a color image comprising color developing a color photographic silver halide light-sensitive material containing at least one compound represented by formula (I) ##STR1## wherein X is a hydrogen atom or an acetyl group, R is an aryl group, and each of R.sub.1, R.sub.2, R.sub.3, and R.sub.4 is a hydrogen atom, an alkyl group, or an aryl group,using a color developer containing a p-phenylenediamine-based and/or p-aminophenol-based color developing agent and without performing black-and-white development.
    Type: Grant
    Filed: March 3, 1982
    Date of Patent: August 14, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Takashi Nakamura, Kotaro Nakamura
  • Patent number: 4456682
    Abstract: A silver halide color photographic material is disclosed. The material has improved developing characteristics which are obtained by containing both a substantially light-insensitive silver halide and at least one specific 3-pyrazolidone compound. The substantially light-insensitive silver halide includes a halogen composition consisting of 0 to 100 percent of bromide, 0 to 2 percent of iodine and the residual percent of chlorine, a mean grain size of 0.01 to 0.3.mu., and a coverage of 5 to 500 mg/m.sup.2. The 3-pyrazolidone compound has the following general formula (I): ##STR1## wherein X represents a hydrogen atom or an acetyl group; R represents an aryl group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each represents a hydrogen atom, an alkyl group or an aryl group, and they may be the same as or different from one another. The material can be developed at an increased speed and is not accompanied by undesirable photographic effects such as fogging.
    Type: Grant
    Filed: September 21, 1982
    Date of Patent: June 26, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Akio Mitsui, Masakazu Morigaki, Takashi Nakamura
  • Patent number: 4444873
    Abstract: A process for processing a silver halide color photographic material is disclosed. The process particularly relates to bleaching and fixing of a color developed silver halide color photographic material. The color developed material is processed with an acid bleaching solution containing a ferric salt, inorganic salt and a halide. Immediately after the bleaching step, the photographic material is processed with the fixing solution containing 5 g/l to 50 g/l of polycarboxylic acids. By utilizing the bleaching and fixing steps disclosed it is possible to process a silver halide color photographic material rapidly utilizing a reduced number of baths, obtain an excellent bleaching rate and produce an image having excellent stability.
    Type: Grant
    Filed: December 29, 1982
    Date of Patent: April 24, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Kiyoshi Imai, Mamoru Tashiro, Junya Nakajima
  • Patent number: 4409324
    Abstract: A multilayer color photographic sensitive material is disclosed. The material is comprised of a support base and a silver halide emulsion layer. The material contains at least one layer containing a high boiling solvent and an oil-soluble coupler, wherein the volume ratio of solvent to coupler is 1/2 or less, and a compound represented by the general formula (I): ##STR1## wherein X is a hydrogen atom or an acetyl group, R is an aryl group, and R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be the same or different, each represents a hydrogen atom, an alkyl group or an aryl group. The material produces sharp images even though it contains a low oil/coupler ratio. Furthermore, there is no retardation of development.
    Type: Grant
    Filed: September 21, 1982
    Date of Patent: October 11, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Akio Mitsui, Masakazu Morigaki, Takashi Nakamura
  • Patent number: 4383027
    Abstract: A silver halide color photographic light-sensitive material comprising a support having thereon a silver halide emulsion layer containing at least one coupler represented by the following general formula (I): ##STR1## The substituents are disclosed in the specification. The silver halide color photographic light-sensitive material in which a specific class of 1-phenyl-3-anilono-4-phyenylthio-5-pyrazolone type two-equivalent magenta color image forming couplers and a specific class of 1-phenyl-3-pyrazolidone derivatives are used in association with each other can provide a magenta color image of high sensitivity without increasing the fog level. A method for developing the material is also disclosed.
    Type: Grant
    Filed: June 23, 1982
    Date of Patent: May 10, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takatoshi Ishikawa, Masakazu Morigaki, Takashi Nakamura, Nobuo Furutate
  • Patent number: 4311574
    Abstract: A method for regenerating a photographic processing solution is disclosed, comprising bringing the photographic processing solution into contact with a particular styrenedivinylbenzene copolymer, and then subjecting the photographic processing solution to ion exchange membrane electrophoresis.
    Type: Grant
    Filed: August 27, 1980
    Date of Patent: January 19, 1982
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takatoshi Ishikawa
  • Patent number: 4293639
    Abstract: The generation of toxic gases from a bleaching composition for silver halide color photographic materials containing a bleaching agent such as a persulfate or an inorganic ferric salt and a water-soluble halide can be prevented by the incorporation therein of a compound represented by the formula [I]:R.sup.1 --X--NH--R.sup.2 [I]wherein X is a carbonyl group or a sulfonyl group; R.sup.1 is an alkyl group, an alkenyl group, a phenyl group, an alkoxy group, an amino group, an acylamino group, or a heterocyclic ring; and R.sup.2 is a hydrogen atom, an alkyl group, an alkenyl group, a phenyl group, an acyl group, a carbamoyl group, or a heterocyclic ring; or R.sup.1 and R.sup.2 together form a 5- or 6-membered ring or a tautomer thereof.
    Type: Grant
    Filed: May 9, 1980
    Date of Patent: October 6, 1981
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Isamu Itoh, Taiji Hashimura, Takatoshi Ishikawa