Antisludgant Patents (Class 430/488)
  • Patent number: 5550009
    Abstract: Color photographic elements are bleached after exposure and development by using a peroxide bleaching solution. This solution comprises a peroxide bleaching agent, chloride ions in an amount of at least 0.35 mol/l, a first acid which is a which is an organic phosphonic acid or a salt thereof, and a second acid which is a 2-pyridinecarboxylic acid or 2,6-pyridinedicarboxylic acid, or a salt thereof. The bleaching solution is stabilized by the presence of the two sequestering acids.
    Type: Grant
    Filed: April 17, 1995
    Date of Patent: August 27, 1996
    Assignee: Eastman Kodak Company
    Inventors: Shirleyanne E. Haye, Mayra B. Reyes
  • Patent number: 5547817
    Abstract: Photographic processing using an additive represented by formula (I): ##STR1## wherein R.sub.1 is an aliphatic hydrocarbon group, an aryl group, or a heterocyclic ring group; R.sub.2 is hydrogen, an aliphatic hydrocarbon group, an aryl group, or a heterocyclic ring group; L.sub.1, L.sub.2, L.sub.3, L.sub.4 and L.sub.5 are independently an alkylene group; m and n are independently 0 or 1; W.sup.1 and W.sup.2 are independently an alkylene group, an arylene group, aralkylene group or a divalent nitrogen-containing heterocyclic ring group; D is a single bond, --O--, --S-- or --N(R.sub.w), where R.sub.2 is hydrogen, an aliphatic hydrocarbon group or an aryl group; v is 0 or an integer or from 1 to 3; w is an integer of from 1 to 3; and M.sub.1, M.sub.2, M.sub.3 and M.sub.4 are independently hydrogen or a cation.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: August 20, 1996
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hisashi Okada, Tadashi Inaba, Ryo Suzuki, Hideaki Nomura
  • Patent number: 5523196
    Abstract: Disclosed is a method for developing a silver halide photographic light-sensitive material with a developer having a pH within the range of 9.5 to 10.7 through an automatic processor, wherein said silver halide photographic light-sensitive material comprises a support and thereon, at least one silver halide emulsion layer comprising silver halide grains containing at least 60 mol % of silver chloride, comprising the steps of:replenishing a first developer replenishing-solution having lower activity than a starter for a developer; andreplenishing a second developer replenishing-solution having the substantially same activity as said starter for a developer.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: June 4, 1996
    Assignee: Konica Corporation
    Inventors: Mariko Iwashita, Takeshi Sampei
  • Patent number: 5510231
    Abstract: A method for processing a silver halide photographic light-sensitive material is disclosed which comprises the steps of:exposing the light-sensitive material;developing the exposed material with a developer; andreplenishing the developer with a repleniser developer in amount of 200 ml or less per m.sup.2 of the material, said developer and replenisher developer are prepared by dissolving in water a solid photographic developing composition comprising a developing agent and a compound selected from the group consisting of compounds represented by the following ##STR1## wherein R.sub.1 and R.sub.2 independently represent a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a hydroxy group, a mercapto group, a carboxyl group, a sulfo group, a phosphono group, an amino group, a nitro group, a cyano group, a halogen atom, an alkoxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a sulfamoyl group or a heterocyclic group, provided that R.sub.1 and R.sub.
    Type: Grant
    Filed: April 22, 1994
    Date of Patent: April 23, 1996
    Assignee: Konica Corporation
    Inventors: Hideki Komatsu, Shoji Nishio
  • Patent number: 5508153
    Abstract: A method for processing an imagewise exposed black-and-white negative silver halide photographic light-sensitive material comprising a support having provided thereon photographic layers including at least one silver halide emulsion layer, one of said photographic layers containing a hydrazine derivative, said method comprising;developing said light-sensitive material with a developer comprising a black and white developing agent and a compound represented by Formula VI, said developer having a pH of less than 11.5; ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 are each independently hydrogen, --SM.sub.1, hydroxyl, alkoxyl having 1 to 5 carbon atoms, --COOM.sub.2, amino, alkyl having 1 to 5 carbon atoms, provided that at least one of R.sub.1, R.sub.2, and R.sub.3 is --SM.sub.1, and M.sub.1 and M.sub.2 are each independently hydrogen, alkali metal, or ammonium.
    Type: Grant
    Filed: January 27, 1995
    Date of Patent: April 16, 1996
    Assignee: Konica Corporation
    Inventors: Wataru Ishikawa, Takeshi Sanpei, Mariko Kato
  • Patent number: 5506092
    Abstract: A method of developing with developer an exposed black and white silver halide photographic light-sensitive material is disclosed, the developer containing a compound represented by the following Formula (1a) , (1b) , (2) or (3) and a compound represented by the following Formula (4) or (5): ##STR1##
    Type: Grant
    Filed: November 30, 1994
    Date of Patent: April 9, 1996
    Assignee: Konica Corporation
    Inventors: Wataru Ishikawa, Takeshi Sampei
  • Patent number: 5503965
    Abstract: The present invention improves the running stability of a developer comprising an ascorbic acid instead of hydroquinone as a developing agent. The present invention provides a process for development of a black-and-white silver halide photographic material, which comprises use of a development replenisher for black-and-white silver halide photographic material comprising an ascorbic acid and/or derivative thereof which has a pH value of at least 0.5 higher than that of the development starting solution.
    Type: Grant
    Filed: September 27, 1994
    Date of Patent: April 2, 1996
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Eiichi Okutsu
  • Patent number: 5462831
    Abstract: To eliminate the "pi-line" artifact after processing a method of image formation is disclosed in a silver halide industrial X-ray photographic material, comprising on at least one side of a support, at least one gelatin silver halide emulsion layer and a total amount of silver halide, corresponding to from 6 to 20 g of silver nitrate per square meter and per side, and at least one non-sensitive protective antistress coating, wherein said material further comprises a hardening agent different from a vinyl sulphone compound, preferably formaldehyde, and at least one polyoxyalkylene compound as a surfactant in at least one of its hydrophilic layers, and wherein after exposure to direct X-rays said material is subjected in an automatic processing machine to the steps of developing in a developer comprising at least one anionic alkylphenoxy polyalkyleneoxy phosphate ester surfactant, fixing in a fixer which may comprise at least one alpha-ketocarboxylic acid, rinsing and drying.
    Type: Grant
    Filed: April 5, 1994
    Date of Patent: October 31, 1995
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Benedictus Jansen, Andre Roefs, Francis Sels, Pieter Perdieus, Raymond Florens
  • Patent number: 5457009
    Abstract: A method of processing a photographic material having, in the backing layer, at least one mercapto pyrimidine compound of formula (I), with an automatic developing machine, where the amount of the replenisher of the developer per unit area of the material being processed is reduced. The processed materials have stable photographic properties and few silver stains. The mercapto pyrimidine has the following structure ##STR1## wherein R.sub.1 and R.sub.2 each represents a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a hydroxyl group, a mercapto group, a carboxyl group, a sulfo group, a phosphono group, a nitro group, a cyano group, a halogen atom, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a sulfamoyl group or an alkoxy group. The sum of the carbon atoms contained in R.sub.1 and R.sub.2 is from 2 to 20. R.sub.1 and R.sub.2 may be bonded to each other to form a ring structure.
    Type: Grant
    Filed: March 17, 1994
    Date of Patent: October 10, 1995
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takashi Toyoda, deceased, Eiichi Okutsu, Kouta Fukui
  • Patent number: 5457011
    Abstract: An improved photographic developing composition, for use in development of a black-and-white silver halide photographic element, is comprised of at least one developing agent and, in an amount sufficient to inhibit sludge deposition, a polyoxyalkylated phosphate ester. The developing composition is broadly useful in black-and-white development but is most advantageously employed in a process for forming a high-contrast image utilizing a silver halide photographic element comprising a hydrazine compound which functions as a nucleating agent and an amino compound which functions as an incorporated booster.
    Type: Grant
    Filed: November 29, 1994
    Date of Patent: October 10, 1995
    Assignee: Eastman Kodak Company
    Inventors: Gordon R. Lehr, Ronald J. Nothnagle
  • Patent number: 5441847
    Abstract: A method of processing, by use of an automatic processor, a black-and-white silver halide photographic light-sensitive material containing a hydrazine compound and a redox compound capable of releasing an inhibitor upon oxidation, wherein a developer is replenished by a developer replenisher at a rate of not more than 200 ml per m.sup.2 of the photographic material, and the developer has a pH of 9.5 to 10.8. The developer further contains a compound represented by the following formulas [1], [2] or [3].
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: August 15, 1995
    Assignee: Konica Corporation
    Inventors: Junichi Fukawa, Takeshi Sampei, Kenji Goto
  • Patent number: 5399457
    Abstract: A method of making a lithographic printing plate that comprises the steps of:(a) imagewise exposing a unitary, light sensitive material which consists of a support, at least one negative working light sensitive silver halide layer and a surface physical development nucleating layer, said construction containing a developing agent and electron transfer agent in one or more layers;(b) processing said printing plate in a diffusion transfer alkaline activator solution containing at least one aminocarboxylic acid complexing agent.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: March 21, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Paul Davies, Elsie A. Fohrenkamm
  • Patent number: 5385811
    Abstract: A method for processing silver halide photographic material is disclosed, which has a support thereon at least one silver halide emulsion layer and at least one protective layer provided over said emulsion layer in which each of the photographic materials contains colloidal silica in at least one emulsion layer and is at most 200% in the total swelling degree of the whole hydrophilic colloid layers provided on the side of said emulsion layer, and after optical exposure said photographic materials are developed with a developer adjusted to pH 9.5-12.0 and containing at least (1) a hydroquinone developing agent in a concentration of from 0.2 to 0.75 mole/l, (2) an auxiliary developing agent of 1-phenyl-3-pyrazolidone type and/or an auxiliary developing agent of p-aminophenol type in a concentration of from 0.001 to 0.06 mole/l, (3) free sulfite ions in a concentration of from 0.3 to 1.
    Type: Grant
    Filed: April 28, 1994
    Date of Patent: January 31, 1995
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Mitsunori Hirano
  • Patent number: 5364746
    Abstract: A developer for developing a silver halide photographic material is disclosed. The developer comprises a compound represented by Formula 1 or Formula 2; ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are each a hydrogen atom or an alkyl group having 1 to 3 carbon atoms provided that both of R.sub.1 and R.sub.2 are not hydrogen atoms at the same time; R.sub.5 is a hydroxy group, an amino group or an alkyl group having 1 to 3 carbon atoms; R.sub.6 and R.sub.7 are each a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an acyl group having 1 to 18 carbon atoms or a --COOM.sub.2 group, provided that both of R.sub.1 and R.sub.2 are not hydrogen atoms at the same time, in the above M.sub.1 is a hydrogen atom, an alkali metal atom or an ammonium group; m is an integer 0, 1 or 2; and M.sub.2 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkali metal atom, an aryl group or an aralkyl group having not more than 15 carbon atoms.
    Type: Grant
    Filed: March 23, 1994
    Date of Patent: November 15, 1994
    Assignee: Konica Corporation
    Inventors: Kenichi Inoue, Tsuyoshi Mitsuhashi
  • Patent number: 5356761
    Abstract: Development of silver halide photosensitive material with a developer containing a developing agent and a free sulfite is accompanied by deposition of silver sludge. Silver sludge is effectively suppressed by adding to the developer (a) a six-membered heterocyclic compound which has a six-membered ring containing two nitrogen atoms and has a mercapto group, a hydroxyl group and one or two substituents having 2 to 20 carbon atoms in total or (a') a six-membered heterocyclic compound which has a six-membered ring containing three nitrogen atoms and has a mercapto group and a hydroxyl group.
    Type: Grant
    Filed: February 28, 1994
    Date of Patent: October 18, 1994
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kiyoshi Morimoto, Hiroshi Hayakawa, Takashi Toyoda, Mitsunori Hirano
  • Patent number: 5310629
    Abstract: A silver recovery element (10) for treating a photographic developer solution containing silver ions comprises a substrate (20) having thereon a hydrophilic colloid layer containing physical development nuclei. The invention also comprises a process for recovering silver from a photographic developer solution containing silver ions, such process comprising contacting the solution with the silver recovery element. The contacting is for a time sufficient to reduce the concentration of silver in the solution to a desired level. The recovery element and process for its use are useful in treating a seasoned photographic developer solution containing silver ions.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: May 10, 1994
    Assignee: Eastman Kodak Company
    Inventors: Hugh G. McGuckin, John S. Badger
  • Patent number: 5304462
    Abstract: A solution containing a water-soluble stilbene sulfonic acid derivative which is used to solubilize oily dye residues in photodeveloper solutions used to develop direct positive silver halide film without generating foam is disclosed.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: April 19, 1994
    Assignee: Anacomp, Inc.
    Inventors: Donald H. Klosterboer, Jerry M. Owens
  • Patent number: 5300410
    Abstract: Disclosed is a developer for silver halide photographic light-sensitive material which contains at least one of the compounds represented by the following formulas [I], [II] and [III]:Formula [I]: ##STR1## wherein M represents a hydrogen atom, an alkali metal or NH.sub.4 and A and B each represents a mercapto group, a hydroxyl group, a hydroxyalkyl group, or ##STR2## wherein R.sub.1 and R.sub.2 each represents a hydrogen atom or --X--Y group in which X represents a divalent group and Y represents a carboxyl group or a hydroxyl group,Formula [II]: ##STR3## wherein M represents a hydrogen atom, an alkali metal or NH.sub.4, A' represents an organic divalent group, and B' represents --SO.sub.3 M', --COOM', --SO.sub.2 NHR.sub.3, --CONHR.sub.3, or --OH wherein M' represents a hydrogen atom, an alkali metal atom or NH.sub.4, and R.sub.
    Type: Grant
    Filed: February 22, 1993
    Date of Patent: April 5, 1994
    Assignee: Mitsubishi Paper Mills Limited
    Inventors: Sukeaki Date, Eiichi Terashima, Toshiro Kondo, Eiji Matsubara, Masao Okushima, Seiichi Sumi
  • Patent number: 5264330
    Abstract: There is disclosed a method for processing a silver halide color photographic material containing a yellow coupler represented by formula (Y) with a color developer containing an aromatic primary amine color developing agent and a polymer of vinyl alcohol or vinyl pyrrolidone series. The disclosure described provides a method for development processing wherein yellow stain and processing nonuniformity in a running processing can be prevented effectively.
    Type: Grant
    Filed: March 13, 1991
    Date of Patent: November 23, 1993
    Assignee: Fuji Photo Film Co. Ltd.
    Inventors: Kazuaki Yoshida, Takatoshi Ishikawa
  • Patent number: 5240823
    Abstract: A developer composition comprising a dihydroxybenzene developing agent, a sulfite ion, and an antisludging agent is diluted with water to prepare a developer for the development of photographic silver halide photosensitive material. The components of the composition are divided into a plurality of parts such that the antisludging agent and the dihydroxybenzene developing agent are added to separate parts which are kept apart during storage until they were combined to form the developer.
    Type: Grant
    Filed: May 23, 1991
    Date of Patent: August 31, 1993
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Minoru Yamada, Takashi Toyoda, Morio Yagihara, Hiroshi Kawamoto
  • Patent number: 5217855
    Abstract: A photographic processing composition containing at one compoud represented by formula (I) ##STR1## wherein R.sub.1 represents a hydrogen atom, an aliphatic group, or an aromatic group, L.sub.1 and L.sub.2 each represents a divalent bonding group including an alkylene group and/or an arylene group; X represents a ##STR2## group (wherein R.sub.a, R.sub.b and R.sub.c each represents a hydrogen atom, an aliphatic group or an aromatic group, and R.sub.d represents an aliphatic group or an aromatic group); and Y represents a carboxy group, a hydroxy group, a phosphono group, a sulfo group or a salt thereof. The processing composition does not produce precipitate or sludge even when contaminated by metallic ions. A processing method using the processing composition is also disclosed.
    Type: Grant
    Filed: July 25, 1991
    Date of Patent: June 8, 1993
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hisashi Okada, Morio Yagihara, Shigeru Nakamura
  • Patent number: 5210009
    Abstract: An element and a process for recovering silver from a photographic developer solution containing silver ions. The silver recovery element (10) comprises a support (12) having a hydrophilic colloid layer (16) containing physical development nuclei on at least one of two opposing outer surfaces. Raised portions (20) space adjacent surfaces in the element's rolled-up configuration. The element can be contacted with the developer solution to recover silver from the solution.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: May 11, 1993
    Assignee: Eastman Kodak Company
    Inventors: Hugh G. McGuckin, John S. Badger
  • Patent number: 5187054
    Abstract: A photographic material is disclosed containing in a non-light sensitive layer above the emulsion layer an anti-sludging compound corresponding to following general formula (I): ##STR1## wherein Ball represents a ballast group, L represents a divalent linking group and Z represents the necessary atoms to close a heterocyclic ring with the proviso that said heterocyclic ring contains no mercapto substituent. The divalent linking group is preferably chosen from the list of --O--, --S--, --CO--NR.sub.1 --, --NR.sub.2 --NR.sub.3 --,--SO.sub.2 --NR.sub.4 --, --O--CR.sub.5 R.sub.6 --CO--NH-- wherein each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 represents hydrogen, alkyl or aralkyl. The heterocyclic ring is preferably chosen from the list of imidazole, benzimidazole, 1,2,3-triazole, 1,2,4-triazole, benzotriazole, tetrazole, indazole, uracil and hydantoin.The non-light sensitive layer, wherein the anti-sludging compound is added, is preferably the top protective layer.
    Type: Grant
    Filed: June 1, 1992
    Date of Patent: February 16, 1993
    Assignee: Agfa-Gevaert N.V.
    Inventors: Jean-Marie O. Dewanckele, Emiel A. Hofman
  • Patent number: 4985348
    Abstract: A process for development-processing a black-and-white silver halide light-sensitive material is disclosed, which comprises using a developer containing at least one compound represented by formulae (I) and (II): ##STR1## wherein R.sub.1 and R.sub.2 each represents hydrogen atom, an alkyl group or an aryl group;M represents hydrogen atom, an alkali metal atom, an alkaline earth metal atom, a quaternary ammonium salt, a quaternary phosphonium salt, an amidino group or a group capable of being converted to hydrogen or an alkali metal atom under alkaline conditions;n represents an integer of 1 or more; andZ.sup..crclbar. represents an anion.
    Type: Grant
    Filed: February 6, 1989
    Date of Patent: January 15, 1991
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Mitsunori Hirano, Masato Hirano, Morio Yagihara, Hisashi Okada
  • Patent number: 4596765
    Abstract: A photographic color forming agent composition comprising an aromatic primary amine color developing agent and materials (A), (B), and (C). Material A is a compound having an aromatic ring bearing two hydroxy groups in the ortho positions thereof. Material B is a hydroxyalkylidene-diphosphonic acid metal ion chelating agent. Material C is at least one metal salt selected from the group consisting of the water-soluble metal salts of magnesium, bismuth, aluminum, zinc, barium, or zirconium. The metal salt is present in an amount in mols equivalent to or more than the amount in mols of metal ion chelating agents of B.
    Type: Grant
    Filed: December 4, 1984
    Date of Patent: June 24, 1986
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Masayuki Kurematsu, Shigeharu Koboshi
  • 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: 4391900
    Abstract: A process for development-processing a silver halide photographic light-sensitive material is described, comprising processing with a developing solution containing 0.1 mol/liter or more of sulfite ion and at least one compound represented by formula (I) ##STR1## wherein n represents an integer of from 2 to 6; each of R.sub.1 and R.sub.2 represents hydrogen or an alkyl group having from 1 to 6 carbon atoms; and M represents hydrogen or an alkali metal atom.According to the process, the generation of silver sludge and the formation of fog are prevented when a black-and-white photographic light-sensitive material is processed with a developing solution containing sulfates in a high concentration.
    Type: Grant
    Filed: January 13, 1982
    Date of Patent: July 5, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takashi Toyoda, Tadao Shishido, Teruaki Tsujikawa
  • Patent number: 4371610
    Abstract: A process for development-processing a silver halide black-and-white photographic light-sensitive material without silver stain and fog by the use of a developing solution which contains 0.1 mole/l or more of sulfite and at least one compound represented by the following general formula (I) or (II) ##STR1## wherein M represents a hydrogen atom, an alkali metal atom or an ammonium group; R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; n represents an integer of 1 to 8; and X represents a sulfonic acid group, a sulfonate group, a carboxylic acid group or a carboxylate group.
    Type: Grant
    Filed: July 24, 1981
    Date of Patent: February 1, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takashi Toyoda, Isamu Itoh, Minoru Yamada
  • Patent number: 4330616
    Abstract: A process of developing a color photographic material with a color developer, a diphosphonic acid and a water soluble metallic salt of magnesium, aluminum, zinc, barium or zirconium.
    Type: Grant
    Filed: July 23, 1981
    Date of Patent: May 18, 1982
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Masayuki Kurematsu, Shigeharu Koboshi
  • Patent number: 4324853
    Abstract: A processing composition adapted for use in a silver diffusion transfer process which includes a saturated polyol containing at least 3 hydroxyl groups wherein each hydroxyl group is no more than 3 carbon atoms away from another hydroxyl group.
    Type: Grant
    Filed: July 18, 1979
    Date of Patent: April 13, 1982
    Assignee: Polaroid Corporation
    Inventor: Michael Berger
  • Patent number: 4323642
    Abstract: Lignosulfonates are incorporated in photographic developing compositions containing an indazole antifoggant in order to prevent or retard the precipitation of the indazole. Both black-and-white developing compositions, containing such developing agents as dihydroxybenzenes and/or pyrazolidones, and color developing compositions, containing primary aromatic amino color developing agents, are effectively stabilized against precipitation of indazole antifoggants by the lignosulfonates.
    Type: Grant
    Filed: March 9, 1981
    Date of Patent: April 6, 1982
    Assignee: Eastman Kodak Company
    Inventor: Steven R. Levinson
  • Patent number: 4310622
    Abstract: A process is described for developing a black-and-white silver halide photosensitive material comprising treating the material with a developing solution containing a sludge preventing compound represented by the formula (I) ##STR1## wherein X represents hydrogen, a hydroxyl group, a lower alkyl group, a lower alkoxy group, a halogen atom, a carboxyl group or a sulfo group, and M.sup.1 and M.sup.2, which may be the same or different, each represents hydrogen, an alkali metal atom, or an ammonium group.
    Type: Grant
    Filed: August 1, 1980
    Date of Patent: January 12, 1982
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shinzaburo Onda, Eiichi Okutsu, Isamu Itoh, Hiroyuki Mifune
  • Patent number: 4254215
    Abstract: A process is described for the prevention of darkening and the formation of a sediment in photographic developer solutions which contain a silver halide developer, a water-soluble silver halide solvent and organic sulfur compounds. The organic sulfur compounds are a combination of (a) an organic thiol compound or thione compound capable of tautomerism and (b) a Bunte salt which contains groups conferring solubility in water. Developer solutions which contain the indicated combination of sulfur compounds are outstandingly stable.
    Type: Grant
    Filed: March 26, 1979
    Date of Patent: March 3, 1981
    Assignee: Ciba-Geigy AG
    Inventors: Ekkehard Kramp, John Lenoir, Max Marthaler
  • Patent number: 4252892
    Abstract: A poly(alkyleneimine), such as poly(ethyleneimine), is incorporated in a photographic color developer composition containing a primary aromatic amino color developing agent in order to protect the developing agent against aerial oxidation. The poly(alkyleneimine) also functions to reduce tar formation and retard stain growth and provides a supplemental source of alkalinity in the color developer composition.
    Type: Grant
    Filed: December 10, 1979
    Date of Patent: February 24, 1981
    Assignee: Eastman Kodak Company
    Inventor: Nelson S. Case