Patents by Inventor Kohzaburoh Yamada

Kohzaburoh Yamada 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: 6297000
    Abstract: A thermographic recording element having at least one image forming layer contains an organic silver salt, a reducing agent, and an adsorption promoting group-bearing alkene compound. The element has high Dmax, high sensitivity, satisfactory contrast and shelf stability.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: October 2, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroyuki Suzuki, Toshihide Ezoe, Kohzaburoh Yamada
  • Patent number: 6277553
    Abstract: A thermographic recording element having at least one image forming layer contains an organic silver salt, a reducing agent, and a nucleating agent. The element has high Dmax, high sensitivity, satisfactory contrast and minimized black pepper.
    Type: Grant
    Filed: October 16, 1998
    Date of Patent: August 21, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masahiko Taniguchi, Kohzaburoh Yamada, Toshihide Ezoe
  • Patent number: 6277554
    Abstract: In a thermographic recording element comprising an organic silver salt, a photosensitive silver halide, and a reducing agent, there are further included a specific compound and a hydrazine derivative. The element exhibits a high contrast and the minimized dependency of photographic properties on developing temperature.
    Type: Grant
    Filed: May 11, 1999
    Date of Patent: August 21, 2001
    Assignee: Fuji Photo Film, Co., Ltd.
    Inventors: Kohzaburoh Yamada, Hiroyuki Suzuki, Toshihide Ezoe
  • Patent number: 6232059
    Abstract: A thermographic recording element having an image forming layer contains an organic silver salt, a reducing agent, an optional photosensitive silver halide, and a specific nucleating agent. The element has high Dmax, high sensitivity, satisfactory contrast, low fog, and minimal dependency of photographic properties on developing temperature.
    Type: Grant
    Filed: December 1, 1998
    Date of Patent: May 15, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kohzaburoh Yamada, Hiroyuki Suzuki, Takashi Hoshimiya, Hirotomo Sasaki, Kohji Kawato, Toshihide Ezoe
  • Patent number: 6177240
    Abstract: A thermographic recording element having an image forming layer contains an organic silver salt, a reducing agent, an optional photosensitive silver halide, and a specific nucleating agent. The element has high Dmax, high sensitivity, satisfactory contrast, and minimal dependency of photographic properties on developing conditions.
    Type: Grant
    Filed: November 17, 1998
    Date of Patent: January 23, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kohzaburoh Yamada, Hiroyuki Suzuki, Toshihide Ezoe
  • Patent number: 6090538
    Abstract: A heat developable light-sensitive material comprising an organic acid silver and silver halide, which contains a compound represented by the following formula (A) and a hydrazine derivative: ##STR1## wherein R represents a hydrogen atom or an alkyl group having from 1 to 10 carbon atoms and R' and R" each represents an alkyl group having from 1 to 5 carbon atoms.
    Type: Grant
    Filed: August 15, 1996
    Date of Patent: July 18, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tsutomu Arai, Toshiaki Kubo, Minoru Sakai, Kohzaburoh Yamada, Kazunobu Katoh
  • Patent number: 6087086
    Abstract: A thermographic recording element having at least one image forming layer contains an organic silver salt, a reducing agent, and a ballast group-bearing alkene compound. The element has high Dmax, high sensitivity, satisfactory contrast and minimized black pepper.
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: July 11, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroyuki Suzuki, Toshihide Ezoe, Kohzaburoh Yamada
  • Patent number: 6074799
    Abstract: A silver halide photographic material comprising a support having thereon at least one photosensitive silver halide emulsion layer, wherein at least one of the silver halide emulsion layer and other hydrophilic colloid layers comprises at least one hydrazine compound represented by the following general formula (II) in the form of fine solid dispersion:A--(B).sub.m (II)wherein A represents a connecting group; B represents a group represented by the following general formula (III); and m represents an integer of from 2 to 6:--(L.sub.2 --Ar.sub.2).sub.n --L.sub.1 --Ar.sub.1 --NHNH--G.sub.1 --R.sub.1(III)wherein Ar.sub.1 and Ar.sub.2 each represents an aromatic group or an aromatic heterocyclic group; L.sub.1 and L.sub.2 each represents a connecting group; n represents an integer of 0 or 1; R.sub.1 represents a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an amino group or a hydrazino group; and G.sub.1 represents a --CO-- group, an --SO.sub.
    Type: Grant
    Filed: October 23, 1998
    Date of Patent: June 13, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Toshihide Ezoe, Kohzaburoh Yamada
  • Patent number: 6048675
    Abstract: A development processing method comprising a step of developing a silver halide photographic material having at least one silver halide emulsion layer with a developing solution containing a hydroquinone developing agent, wherein said developing solution has a pH of from 9.0 to 11.0, and contains a compound represented by formula (I) and a compound represented by formula (II) in a concentration ratio of the compound represented by formula (II)/the hydroquinone developing agent of from 0.03 to 0.12: ##STR1## wherein the symbols in these formulae are defined in the specification.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: April 11, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Mitsunori Hirano, Kohzaburoh Yamada
  • Patent number: 6017674
    Abstract: A silver halide photographic material comprising a support having thereon at least one photosensitive silver halide emulsion layer, wherein at least one of the silver halide emulsion layer and other hydrophilic colloid layers comprises at least one hydrazine compound represented by the following general formula (II) in the form of fine solid dispersion:A--(B).sub.m (II)wherein A represents a connecting group; B represents a group represented by the following general formula (III); and m represents an integer of from 2 to 6:--(L.sub.2 --Ar.sub.2).sub.n --L.sub.1 --Ar.sub.1 --NHNH--G.sub.1 --R.sub.1(III)wherein Ar.sub.1 and Ar.sub.2 each represents an aromatic group or an aromatic heterocyclic group; L.sub.1 and L.sub.2 each represents a connecting group; n represents an integer of 0 or 1; R.sub.1 represents a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an amino group or a hydrazino group; and G.sub.1 represents a --CO-- group, an --SO.sub.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: January 25, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Toshihide Ezoe, Kohzaburoh Yamada
  • Patent number: 5994040
    Abstract: A processing composition for silver halide photographic light-sensitive material, which comprises at least one compound represented by the following formula (A), (A-I) or (A-II) and at least one compound represented by the following formula (B): ##STR1## Also disclosed are a developer prepared from the processing composition, and a processing method using the developer.
    Type: Grant
    Filed: March 4, 1997
    Date of Patent: November 30, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shinnichi Morishima, Kohzaburoh Yamada, Seiji Yamashita, Minoru Sakai, Kouta Fukui, Eiichi Okutsu
  • Patent number: 5981138
    Abstract: A hydrazine compound represented by the following formula (I):Ar.sub.1 --NH--NH--G.sub.1 --R.sub.1 (I)wherein Ar.sub.1 represents an aromatic group; G.sub.1 represents a carbonyl group, a sulfonyl group, a sulfoxy group, a phosphoryl group, an oxalyl group or an iminomethylene group; R.sub.1 represents a hydrogen atom or a block group; and at least one of Ar.sub.1 and R.sub.1 has a group represented by the following formula (II): ##STR1## wherein * represents a bond for connecting directly or through a liking group to Ar.sub.1 or R.sub.1 ; Z represents a nonmetallic atom group capable of forming a 5- or 6-membered unsaturated heterocyclic ring having a conjugated positive charge; and X.sup.- represents --O.sup.-, --S.sup.- or --N.sup.- --R.sub.2, wherein R.sub.2 represents an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heterocyclic group. Also disclosed is a silver halide photographic light-sensitive material containing the hydrazine compound.
    Type: Grant
    Filed: September 4, 1997
    Date of Patent: November 9, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroyuki Suzuki, Kohzaburoh Yamada, Hiroshi Takeuchi, Toshihide Ezoe, Takashi Hoshimiya
  • Patent number: 5976758
    Abstract: A development processing method which comprises the steps of: imagewise exposing a silver halide photographic light-sensitive material; and developing the exposed photographic material with a developing solution, wherein the silver halide photographic material comprises a support having thereon at least one light-sensitive silver halide emulsion layer, at least one of the silver halide emulsion layer and other hydrophilic colloidal layers containing at least one hydrazine derivative; and wherein the developing solution is substantially free from a dihydroxybenzene compound, has a pH of from 9.0 to 10.5 and contains (1) at least one ascorbic acid developing agent, (2) at least one 1-phenyl-3-pyrazolidone auxiliary developing agent and (3) a compound represented by the following formula (I): ##STR1## wherein R.sub.1 to R.sub.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: November 2, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kouta Fukui, Senzo Sasaoka, Kohzaburoh Yamada
  • Patent number: 5972580
    Abstract: A development processing method comprises: exposing a silver halide light-sensitive material comprising a support having thereon at least one light-sensitive silver halide emulsion layer; and developing said exposed light-sensitive material with a developing solution, wherein at least one of said silver halide emulsion layer and other hydrophilic colloidal layers contains at least one hydrazine derivative, and wherein said developing solution is substantially free from a dihydroxybenzene compound, has a pH of from 9.0 to 10.5, and contains (1) at least one ascorbic acid derivative developing agent, (2) at least one aminophenol auxiliary developing agent and (3) a specific mercaptopyrimidine compound. The processing method provides a high-contrast image required in the field of graphic arts using a developing solution having no problem with respect to the ecosystem and working environment, without causing silver stain even at a low replenishment rate.
    Type: Grant
    Filed: November 21, 1997
    Date of Patent: October 26, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kouta Fukui, Kohzaburoh Yamada
  • Patent number: 5962212
    Abstract: A thermographic recording element comprising an organic acid silver salt, a reducing agent, a specific hydrazine derivative, and optionally, a photosensitive silver halide is improved in storage stability and forms images having high Dmax.
    Type: Grant
    Filed: June 3, 1998
    Date of Patent: October 5, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroyuki Suzuki, Toshiaki Kubo, Kohzaburoh Yamada
  • Patent number: 5888694
    Abstract: A silver halide photographic material is described, which comprises a compound represented by the following formula (I) or (II):A.paren open-st.(L).sub.m --B).sub.n (I)(A--(L).sub.m .paren close-st..sub.n B (II)wherein A represents an adsorption accelerating group to silver halide or a precursor thereof; B represents a quaternised nitrogen-containing heterocyclic ring and a counter ion thereof; L represents a linking group; m represents 0 or 1; and n represents an integer of from 1 to 4. An image formation method is also described, which comprises the steps of exposing the above-described silver halide photographic material and developing the exposed material with a specific developer.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: March 30, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kohzaburoh Yamada, Toshiaki Kubo
  • Patent number: 5882841
    Abstract: A silver halide photographic light-sensitive material comprising a support having thereon at least one light-sensitive silver halide emulsion layer, wherein at least one of the silver halide emulsion layer and other hydrophilic colloid layers comprises fine polymer particles containing at least one hydrazine compound represented by the following general formula (NB):A--(B).sub.m (NB)wherein A represents a connecting group; m represents an integer of from 2 to 6; and B represents a group containing a hydrazine structure. The sliver halide photographic light-sensitive material exhibits an ultrahigh contrast, an excellent storage stability and an excellent processing stability and is prevented from the occurrence of processing unevenness. A method for processing the silver halide photographic light-sensitive material is also disclosed.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: March 16, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Toshihide Ezoe, Kouta Fukui, Kohzaburoh Yamada
  • Patent number: 5858610
    Abstract: An image forming method comprising developing a silver halide photographic light-sensitive material which comprises a support having thereon at least one light-sensitive silver halide emulsion layer: wherein the silver halide photographic light-sensitive material contains at least one kind of hydrazine derivative represented by general formula (NB) in at least one layer of the silver halide emulsion layer(s) and other hydrophilic colloidal layers:A--(B).sub.m (NB)and wherein the development is conducted by using a developing solution having a pH of from not less than 8.5 to less than 11.0, which developing solution does not substantially contain a dihydroxybenzene developing agent, but contains a developing agent represented by general formula (1): ##STR1## The symbols used in the above formulas are defined in the specification.
    Type: Grant
    Filed: April 17, 1997
    Date of Patent: January 12, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Toshihide Ezoe, Kohzaburoh Yamada
  • Patent number: 5840472
    Abstract: A developer for a silver halide photographic photosensitive material containing at least one of monocyclic dimercaptotriazine compounds, bis-type dimercaptotriazine compounds, mercapto-1,2,4-triazine compounds and dimercaptopyrimidine compounds, and a process for developing a silver halide photographic photosensitive material using the developer. The compounds of the present invention provides excellent effect in preventing silver stains without affecting the photographic properties of the photographic material.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: November 24, 1998
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hirotomo Sasaki, Harumi Watanabe, Kohzaburoh Yamada
  • Patent number: 5789139
    Abstract: A hydrazide compound represented by the following formula (I), and a silver halide photographic photonsensitive material comprising the hydrazide compound:A--(B).sub.b (I)wherein A represents a heterocyclic group, a condensed polycyclic aromatic group or a group formed by connecting at least two aromatic groups to each other, B represents a group represented by the following formula (I-B) or (II-B), and b represents an integer from 2 to 6;--L.sub.1 --Ar.sub.1 --NHNH--G.sub.1 --R.sub.1 (I-B)--L.sub.3 --Ar.sub.3 --L.sub.2 --Ar.sub.2 --NHNH --G.sub.2 --R.sub.2(II-B)wherein each of G.sub.1 and G.sub.2 represents a carbonyl group, an oxalyl group, a sulfonyl group or a phosphoryl group; each of R.sub.1 and R.sub.2 represents a hydrogen atom or a blocking group; each of Ar.sub.1, Ar.sub.2 and Ar.sub.3 represents an aromatic group or an aromatic heterocyclic group; and each of L.sub.1, L.sub.2 and L.sub.3 represents a linkage group.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: August 4, 1998
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kohzaburoh Yamada, Hiroyuki Suzuki, Toshihide Ezoe, Koji Kawato