Patents by Inventor Atsuhiro Ohkawa

Atsuhiro Ohkawa 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: 6562542
    Abstract: An image-forming material is described, comprising on an support an acid-generating agent selected from a sulfonic acid ester of a specific structure generating an acid by the action of heat and the polymer thereof, and a compound causing a light absorption change in the absorption region of from 350 to 700 nm by an intramolecular or intermolecular reaction by the action of an acid. The image-forming material has a high sensitivity and excellent storage stability and gives low haze and good images in the case of performing image formation using a high-output laser light.
    Type: Grant
    Filed: March 28, 2001
    Date of Patent: May 13, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Atsuhiro Ohkawa, Seiya Sakurai
  • Publication number: 20030011725
    Abstract: An optical film comprises a transparent support and a polarizing layer. The polarizing layer selectively transmits polarized light, and selectively reflects or scatters other polarized light. The polarizing layer contains a compound represented by the formula (I) of Ar1—C≡C—Ar3—C≡C—Ar2. In the formula (I), each of Ar1 and Ar2 independently is a monovalent aromatic group, and Ar3 is a divalent aromatic group.
    Type: Application
    Filed: February 19, 2002
    Publication date: January 16, 2003
    Inventors: Atsuhiro Ohkawa, Hiroki Sasaki, Kensuke Morita, Ichiro Amimori
  • Patent number: 6432876
    Abstract: According to the present invention, a coloring property-improved novel leuco dye which can develop color by heat even with single molecule without requiring excess developer can be obtained, and an image recording medium having high sensitivity and excellent resolution effected by including the dye and a high sensitivity image recording medium further combined with an acid generator can also be obtained. Particularly, it relates to a leuco dye represented by a formula (1) (LD—(A—P1)n) and to an image recording medium which contains the leuco dye (wherein LD represents an acid-sensitive leuco dye mother nucleus, —A represents the residue of an acidic group (—AH) selected from —SO3H, —CO2H and —P(═O)(OH)xRy, R represents a hydrogen atom or a substituent group, x and y are x=1 and y=1 or x=2 and y=0, P1 represents a protecting group which can be removed by the action of light, heat or acid, and n is an integer of 1 or more).
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: August 13, 2002
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tatsuhiko Obayashi, Atsuhiro Ohkawa
  • Patent number: 6409328
    Abstract: Disclosed are an image forming method including forming images in an image-forming material by means of a thermal printer head, wherein the image-forming material including a compound capable of releasing a strong acid under the action of heat and a compound capable of forming a dye by the reaction with an acid, and an image-forming material suitable for printing with a thermal head.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: June 25, 2002
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Atsuhiro Ohkawa
  • Publication number: 20020037480
    Abstract: An image-forming material is described, comprising on an support an acid-generating agent selected from a sulfonic acid ester of a specific structure generating an acid by the action of heat and the polymer thereof, and a compound causing a light absorption change in the absorption region of from 350 to 700 nm by an intramolecular or intermolecular reaction by the action of an acid. The image-forming material has a high sensitivity and excellent storage stability and gives low haze and good images in the case of performing image formation using a high-output laser light.
    Type: Application
    Filed: March 28, 2001
    Publication date: March 28, 2002
    Inventors: Atsuhiro Ohkawa, Seiya Sakurai
  • Patent number: 6329121
    Abstract: An image recording medium is disclosed which comprising: an acid generating agent capable of generating an acid by the action of heat or an acid, which is represented by the following formula (1); and a compound of causing variation in the absorption region of from 360 to 900 nm by the intramolecular or intermolecular reaction triggered by the action of an acid: W1OP  (1) wherein W1 represents a residue of an acid represented by W1OH, and P represents an acid-sensitive substituent capable of splitting off at a temperature of 150° C. or less due to catalysis by W1OH.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: December 11, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tatsuhiko Obayashi, Junichi Yamanouchi, Atsuhiro Ohkawa
  • Patent number: 6329120
    Abstract: An image recording medium is disclosed which comprising: an acid generating agent capable of generating an acid by the action of heat or an acid, which is represented by the following formula (1); and a compound of causing variation in the absorption region of from 360 to 900 nm by the intramolecular or intermolecular reaction triggered by the action of an acid: W1OP  (1) wherein W1 represents a residue of an acid represented by W1OH, and P represents an acid-sensitive substituent capable of splitting off at a temperature of 150° C. or less due to catalysis by W1OH.
    Type: Grant
    Filed: May 16, 2000
    Date of Patent: December 11, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tatsuhiko Obayashi, Junichi Yamanouchi, Atsuhiro Ohkawa
  • Patent number: 6316161
    Abstract: Disclosed is an image recording medium which comprises a compound having at least one substituent group removable by the action of heat, an acid or light and capable of producing an acid by an intramolecular nucleophilic substitution subsequent to the removal of the substituent group to acquire both high sensitivity and excellent storage quality.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: November 13, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tatsuhiko Obayashi, Tatsuya Igarashi, Atsuhiro Ohkawa
  • Publication number: 20010016297
    Abstract: An image recording medium is disclosed which comprising: an acid generating agent capable of generating an acid by the action of heat or an acid, which is represented by the following formula (1); and a compound of causing variation in the absorption region of from 360 to 900 nm by the intramolecular or intermolecular reaction triggered by the action of an acid:
    Type: Application
    Filed: December 21, 2000
    Publication date: August 23, 2001
    Inventors: Tatsuhiko Obayashi, Junichi Ymanouchi, Atsuhiro Ohkawa
  • Patent number: 6203964
    Abstract: A thermal recording medium comprising a ultraviolet absorber precursor represented by formula (1-A) or an image forming compound changing hue and an acid, which is high in thermal sensitivity, recordable with such a low output laser that no ablation takes place even when a thermal heat mode image recording system using a laser is utilized, requiring no different receiving sheet, and excellent in keeping quality: wherein P represents a protecting group for a hydroxyl group which is deblocked by heating to 250° C. or less in the presence of an acid; R1 and R2, which may be the same or different, each represents a substitutable group; and 1 and m each represents an integer of 0 to 4.
    Type: Grant
    Filed: March 13, 2000
    Date of Patent: March 20, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tatsuhiko Obayashi, Junichi Yamanouchi, Atsuhiro Ohkawa
  • Patent number: 6197725
    Abstract: There is provided a coupler giving a magenta pigment excellent in hue using a diazonium salt compound which can be fixed at a wavelength around 420 nm.
    Type: Grant
    Filed: December 1, 1998
    Date of Patent: March 6, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Atsuhiro Ohkawa, Hisao Yamada
  • Patent number: 6143480
    Abstract: Disclosed is a leuco dye in which a hydrogen atom capable of transferring by isomerization in a dye represented by formula (1) or a tautomer thereof is substituted by a substituent group P which can be removed by the action of heat or acid ##STR1## wherein (A) represents an atomic group necessary for forming a nitrogen-containing hetero ring; (B) represents an atomic group necessary for forming a six-membered hetero ring; and X represents an oxygen atom, a sulfur atom or a nitrogen atom, which may have a hydrogen atom or a possible substituent group.
    Type: Grant
    Filed: September 1, 1999
    Date of Patent: November 7, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tatsuhiko Obayashi, Atsuhiro Ohkawa
  • Patent number: 6100009
    Abstract: An image recording medium is disclosed which comprising: an acid generating agent capable of generating an acid by the action of heat or an acid, which is represented by the following formula (1); and a compound of causing variation in the absorption region of from 360 to 900 nm by the intramolecular or intermolecular reaction triggered by the action of an acid:W.sup.1 OP (1)wherein W.sup.1 represents a residue of an acid represented by W.sup.1 OH, and P represents an acid-sensitive substituent capable of splitting off at a temperature of 150.degree. C. or less due to catalysis by W.sup.1 OH.
    Type: Grant
    Filed: October 15, 1998
    Date of Patent: August 8, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tatsuhiko Obayashi, Junichi Yamanouchi, Atsuhiro Ohkawa
  • Patent number: 6060206
    Abstract: Disclosed is a photo- and heat-sensitive recording material comprising a substrate and a photo- and heat-sensitive recording layer formed thereon containing a diazo compound and a coupler, wherein the coupler is a compound represented by the general formula (1) or the general formula (2): ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each independently a hydrogen atom or a substituent group; and R.sup.1 and R.sup.2 may join with each other to form a ring. The reaction between the coupler represented by the general formula (2) and a specific diazo compound produces a magenta colorant having very sharp absorption characteristics. In short, the present invention provides a photo- and heat-sensitive recording material which does not inhibit the fixing and which exhibits excellent color formation, color reproduction, and image durability. Further, the present invention provides a magenta colorant which exhibits excellent absorption characteristics.
    Type: Grant
    Filed: October 1, 1998
    Date of Patent: May 9, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Koichi Hanaki, Yasuhiro Mitamura, Atsuhiro Ohkawa
  • Patent number: 6051359
    Abstract: The present invention provides a heat-developable light-sensitive material having a support and a light-sensitive layer provided on the support. The heat-developable light-sensitive material contains dyes which are decolorized through reaction with a decolorizing agent during a development process. The dyes are non-diffusible and at least a part of decolorized dyes resulting from the development process is non-diffusible. Also provided is an image forming method using the heat-developable light-sensitive material. The present method provides images having excellent sharpness within a short period of time.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: April 18, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Atsuhiro Ohkawa, Hiroo Takizawa, Shun-ichi Ishikawa, Takuya Yokokawa
  • Patent number: 5837438
    Abstract: A compound represented by the following general formula (I) is added to at least one layer of a silver halide photographic photosensitive material, thereby improving sharpness and graininess or decreasing a variation in photographic performance during storage after photography and before development: ##STR1## where A represents a coupler moiety, each of R.sup.1 and R.sup.2 independently represents a hydrogen atom or a substituent, each of R.sup.3 and R.sup.4 independently represents a hydrogen atom or an alkyl group, INH represents a group having a development inhibiting function, and R.sup.5 represents a nonsubstituted phenyl group, a nonsubstituted primary alkyl group, or a primary alkyl group substituted with a group other than an aryl group, at least one of R.sup.1 to R.sup.4 being a substituent other than a hydrogen atom, and an --OC(.dbd.O)-- group combining with one of two nitrogen atoms forming a pyrazole ring.
    Type: Grant
    Filed: March 23, 1993
    Date of Patent: November 17, 1998
    Assignee: Fuji Photo Film, Co., Ltd.
    Inventors: Atsuhiro Ohkawa, Keiji Mihayashi
  • Patent number: 5665529
    Abstract: A color diffusion transfer photographic material is described, which comprises at least one compound represented by the following formula (I): ##STR1## wherein R.sup.1 and R.sup.2 each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and R.sup.1 and R.sup.2 may be linked to form a ring directly or via an oxygen atom or a nitrogen atom; R.sup.3 represents an --NHSO.sub.2 R.sub.10 group, an --SO.sub.2 NHCOR.sub.10 group, an --SO.sub.2 NHSO.sub.2 R.sub.10 group, an --NHCOR.sub.10 group or an --OH group; R.sub.10 represents an alkyl group; R.sup.4 and R.sup.5 each represents a substituent and when there are a plurality of R.sup.4 and R.sup.5, they may be the same or different; CAR represents a group which releases a dye different from the compound represented by formula (I) in diffusibility by oxidation; x and y each represents 0 or an integer of 1, 2, 3 or 4; and z represents 0 or 1.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: September 9, 1997
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Atsuhiro Ohkawa, Hisashi Mikoshiba, Masaaki Tsukase, Yasuhiro Ishiwata, Hideaki Naruse
  • Patent number: 5547824
    Abstract: Disclosed is a silver halide color photographic light-sensitive material which contains an emulsion in which the silver iodide surface content of the silver halide grains is less than the average silver iodide content of the grains. The material also contains a compound capable of releasing two photographically useful groups through at least one timing group and/or a compound capable of releasing a photographically useful group through two timing groups.
    Type: Grant
    Filed: July 7, 1992
    Date of Patent: August 20, 1996
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Keiji Mihayashi, Atsuhiro Ohkawa
  • Patent number: 5529894
    Abstract: Disclosed is a silver halide color photographic material which comprises a support having thereon at least one photosensitive silver halide emulsion layer, a pyrazoloazole based magenta coupler, and a coupler which contains a plurality of photographically useful groups or precursors thereof. The photograhically useful groups or precursors thereof are capable of being released when the coupler undergoes a coupling reaction with the oxidized product of a color developing agnet.
    Type: Grant
    Filed: March 9, 1994
    Date of Patent: June 25, 1996
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Keiji Mihayashi, Atsuhiro Ohkawa
  • Patent number: 5514529
    Abstract: A light-sensitive material having at least one emulsion layer containing silver halide grains, wherein tabular grains having an average aspect ratio of 2 or more occupy at least 50% of the total projected area of all grains, and the material contains a compound which releases two photographically useful groups from one molecule through a timing group and/or a compound which releases a photographically useful group through two timing groups.
    Type: Grant
    Filed: June 30, 1992
    Date of Patent: May 7, 1996
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Keiji Mihayashi, Atsuhiro Ohkawa