US3502467A - High temperature processing in dyedeveloper diffusion transfer systems - Google Patents

High temperature processing in dyedeveloper diffusion transfer systems Download PDF

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US3502467A
US3502467A US689779A US3502467DA US3502467A US 3502467 A US3502467 A US 3502467A US 689779 A US689779 A US 689779A US 3502467D A US3502467D A US 3502467DA US 3502467 A US3502467 A US 3502467A
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dye
silver halide
bis
processing
dye developer
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Richard W Becker
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Eastman Kodak Co
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Eastman Kodak Co
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C8/00—Diffusion transfer processes or agents therefor; Photosensitive materials for such processes
    • G03C8/02—Photosensitive materials characterised by the image-forming section
    • G03C8/08—Photosensitive materials characterised by the image-forming section the substances transferred by diffusion consisting of organic compounds
    • G03C8/10—Photosensitive materials characterised by the image-forming section the substances transferred by diffusion consisting of organic compounds of dyes or their precursors
    • G03C8/12—Photosensitive materials characterised by the image-forming section the substances transferred by diffusion consisting of organic compounds of dyes or their precursors characterised by the releasing mechanism
    • G03C8/14—Oxidation of the chromogenic substances
    • G03C8/16—Oxidation of the chromogenic substances initially diffusible in alkaline environment

Definitions

  • This invention relates to the art of photography and more particularly to a dye diffusion transfer process in photography and materials adapted for use in the process.
  • a diffusion transfer color process has been described in a number of patents, including British Patent 804,971, published Nov. 26, 1958, wherein photographic elements containing silver halide emulsion layers and layers containing diifusible dye developers (dyes having a silver halide developing function) are exposed to record the latent image in the silver halide and then treated with an alkaline processing composition which permeates the emulsion layers and layers containing the dye developers which then develop the latent images to silver images. At the same time oxidation products of the dye developers are formed in situ with the silver images and which are relatively nondiffusing in the colloid vehicle of the layers.
  • the non-diffusing character of the oxidized dye developers is apparently due at least in part to a decrease in solubility in the alkaline processing liquid, and may also be due to a hardening effect of the oxidized developer upon the colloid vehicles of the layers which retards the diffusion of the oxidized dye developers.
  • the residual unoxidized dye developers remaining in the layers in imagewise distribution are transferred by diffusion to a superposed reception element substantially to the exclusion of the silver image and oxidized dye developer to provide a positive dye image.
  • an alkaline processing composition is utilized partly to initiate the development of the emulsion layers and also to act as a medium through which the unoxidized dye developer images and other substances diffuse to and from the receiving layer.
  • the processing composition is usually spread in limited quantity between the surface of the light-sensitive or negative element and a mordanted receiving sheet. It is therefore desirable to include in the processing composition a thickening agent which increases the viscosity thereof, particularly for in-camera processing wherein the processing composition is utilized in a rupturable pod or like container.
  • the temperature of processing will, of course, depend upon the prevalent ambient temperature. Such temperatures can vary over a wide range. Thus, ambient temperatures as high as 3,502,467 Patented Mar. 24, 1970 "Ice F. or above may be encountered, for example, in desert or tropical regions.
  • a further object of this invention is to provide an improved dye developer diffusion transfer system for use at elevated temperatures.
  • the silver halide in the regions of exposure is developed and the contiguous dye developers are immobilized, Thereafter, dye developers from the unexposed and undeveloped areas of the photographic element diffuse and are transferred in register to a reception layer to form positive dye developer images.
  • dye developer diffusion transfer elements can be processed at elevated temperatures and still yield transferred images having satisfactory maximum densities, if the element is processed in the presence of a bis-benzothiazolium salt wherein two benzothiazoli-um salt groups are joined, at the respective heterocyclic nitrogen atoms thereof, by a long chain alkylene group.
  • Typical useful bis-benzothiazolium salts are represented by the general formula wherein R represents a hydrogen atom or a lower alkyl group, .such a methyl, ethyl, etc.
  • D represents the non-metallic atoms necessary to complete a benzene nucleus as well as substitution products thereof, including such member substituted by methyl, ethyl, methoXyl, ethoxyl, etc.
  • 11 represents a positive integer of from 626
  • X represents an acid anion, such as perchlorate, bromide, benzenesulfonate, toluenesulfonate, methyl su1- fate, ethyl sulfate, etc.
  • the long chain bis-'benzothiazolium salts of the present invention act as controlled development restrainers in such systems and permit the attainment of high maximum densities at elevated temperatures.
  • the development restrainers of the present invention inhibit development of unexposed silver halide.
  • the restraint of development of the silver halide results in more dye developer being available for diffusion into the receiving layer.
  • the maximum density of the print is increased without substantially increasing the minimum density.
  • the development restrainers of the present invention have the highly desirable characteristic of having no significant effect on the systems at ordinary room temperatures, i.e., about 70 F., while becoming effective at those temperatures above ordinary room temperatures, e.g., between about 85 and 130 F.
  • Representative long chain bis-benzothiazolium salts include:
  • the long chain bis compound of the present invention is provided in the dye developer system of the present in- 'vention in such a manner that it is present during processing at elevated temperatures as an active development restrainer.
  • the long chain salt is preferably utilized in one or more of the layers of the photosensitive element, e.g., the silver halide emulsion layer, although it may be provided in the image-receiving element or in the alkaline processing composition.
  • the concentration of salt effective to restrain high temperature development varies over a wide range. Concentrations should be increased with higher processing temperatures. Generally, between about 0.005 and about 0.1 g./Ag mole, preferably between about 0.015 and about 0.03 g./Ag mole is suitable to achieve satisfactory maxiinum Fdensities at elevated temperatures, such as
  • the long chain bis-benzothiazolium salts of the present invention can be incorporated into any hydrophilic colloid layer of the photosensitive element, e.g., the silver halide emulsion layer, the dye-developer layer, an interlayer, etc., as an aqueous solution, an alcohol-water solution, or by any other manner known in the art.
  • Dye developers are well known in the photographic art. Such compounds function both as a silver halide developing agent and as a dye in photographic difi-usion transfer systems.
  • Dye developers are characterized as bemg relatively nonditfusible in colloid layers such as the hydrophilic organic colloids used in photographic emul- 810118 at neutral pH, but diffusible in the photographic elements in the presence of alkaline processing solutions.
  • dye developers are substantially insoluble in water, which property usually necessitates the use of organic solvents to incorporate the dye developers into the organic colloid layers of the photo-elements.
  • the dye developers are particularly characterized as containing both a chromophoric or dye moiety and at least one moiety having a silver halide developing agent function.
  • Particularly useful dye developers are those wherein the chromophoric moiety as an azo or anthraquinone dye moiety and the silver halide developing moiety is a benzenoid moiety such as a hydroquinonyl moiety.
  • M is an aromatic or heterocyclic ring or ring system such as a benzene, naphthalene, tetralin, anthracene, anthraquinone, pyrazole, quinoline, etc., ring which can be substituted with such groups as hydroxyl, amino, keto, nitro, alkoxy, aryloxy
  • D represents a silver halide developing agent moiety, imparting the developing agent function to the dye developer such as a hydroquinonyl group which can be substituted with amino, alkylarnino, alkyl, hydroxyl, alkoxyl or halogen groups.
  • Typical useful dye developers are described in U.S. Patents 3,146,102 and 3,161,506 as well as elsewhere in the patent literature, including: Australian 220,279; German 1,036,640; British 804,971 and 804,973-5; Belgian 554,935; French 1,168,292; and Canadian 577,021 and 579,938.
  • the dye developers are preferably incorporated in hydrophilic organic colloidal vehicles or carriers comprising the layers of the photographic element dissolved in high-boiling or crystalloidal solvents and dispersed in finel -divided droplets.
  • hydrophilic organic colloidal vehicles or carriers comprising the layers of the photographic element dissolved in high-boiling or crystalloidal solvents and dispersed in finel -divided droplets.
  • Typical high-boiling, Water-insoluble solvents that can be used to dissolve dye developers in preparing the dispersions of the invention are described in U.S. Patent 2,322,027.
  • the dye developers utilized in the photographic elements useful in the invention can also be incorporated into vehicles soluble in organic solvents which are also solvents for the dye developers. Likewise, other incorporating techniques for the dye developers such as ball-milling can be utilized.
  • the dye developers are utilized contiguous to the silver halide of the photographic silver halide emulsion layers of the present photographic elements. Such dye developers can be incorporated directly in the silver halide emulsions or preferably positioned in a sublayer contiguous to each silver halide emulsion layer.
  • the contiguity of the dye developer with respect to the silver halide can take the form of a mixed packet system wherein the dye developer can be present in a matrix surrounding a particle or globule containing silver halide grains.
  • the dye developers are preferably substantially complementary in color to the color of the light recorded or spectral sensitivity of the silver halide emulsions contiguous thereto.
  • colorless hydroquinone derivatives can be utilized in the dye developer diffusion transfer sys tems of the invention. Such colorless hydroquinone derivatives are substantially insoluble in water and ditfusible in the hydrophilic organic colloids comprising the present photographic elements in the presence of alkaline processing compositions. Typical suitable colorless hydroquinone derivatives are listed in U.S. Patent 3,146,102 and are preferably employed in one or more layers of the light-sensitive element.
  • onium compounds can also be utilized in the present invention.
  • Such onium compounds that is, compounds that contain an organic cation, are diifusible in the hydrophilic organic colloids comprising the present photographic elements in the presence of alkaline processing compositions.
  • Such onium compounds are typically quaternary ammonium compounds, quaternary phosphonium compounds or tertiary sulfonium compounds.
  • a particularly useful class of onium compounds are heterocyclic quaternary ammonium compounds that are capable of forming diffusible methylene bases in alkaline processing compositions such as those described in U.S. Patent 3,146,102.
  • the onium compounds are preferably utilized in the alkaline processing composition, although the onium compounds can also be utilized in the reception sheet, or less desirably, in one or more layers of the light-sensitive element, or in at least two of such positions.
  • Water-soluble silver halide solvents can be employed in the alkaline processing compositions used in the dye developer transfer process of the invention, particularly in conjunction with onium compounds and colorless hydroquinone derivatives as described above, such addenda lending further improvement in color quality results.
  • Preferred silver halide solvents are thiosulfates such as sodium, potassium and ammonium thiosulfate.
  • the silver halide emulsions utilized in preparing photographic or light-sensitive elements used in the present diffusion transfer systems can be any of the conventional negative-type, developing-out emulsions.
  • Typical suitable silver halides include silver chloride, silver bromide, silver bromoiodide, silver chloroiodide, silver chlorobromoiodide and the like. Mixtures of more than one of such silver halides can also be utilized.
  • such silver halide emulsions can contain spectral sensitizers, hardeners, coating aids, plasticizers, antifoggants and the like conventional emulsion addenda.
  • hydrophilic organic colloids can be utilized as the vehicle or carrier.
  • Gelatin is preferably used as the hydrophilic colloid or carrier material although such material as polyvinyl alcohol and its water-soluble derivatives and copolymers, water-soluble copolymers such as polyacrylamide, imidized polyacrylamide, etc., and other water-soluble film-forming materials that form waterpermeable coats such as colloidal albumin, water-soluble cellulose derivatives, etc., can be utilized in preparing the photographic elements. Compatible mixtures of two or more of such colloids can also be utilized.
  • Typical supports include cellulose nitrate film, cellulose acetate film, polyvinyl acetal film, polystyrene film, polyethylene terephthalate film, polyethylene film, polypropylene film, paper, polyethylenecoated paper, polypropylene-coated paper, glass and the like.
  • receiving sheets can be utilized to receive the transfer images from the photographic elements.
  • Typical reception layers for receiving sheets include such materials as linear polyamides, proteins such as gelatin, polyvinyl pyrrolidones, poly-4-vinyl pyridine, polyvinyl alcohol, polyvinyl salicylal, partially hydrolyzed polyvinyl acetate, methyl cellulose, regenerated cellulose, or mixtures of such.
  • These reception layers can be coated on a suitable support of the type described above for the light-sensitive elements of the invention and including transparent as well as opaque supports.
  • receiving sheets that release acidic material such as that derived from an acidic polymer or other acidic compound as a controlled rate as are described in U.S.
  • Patent 2,584,030 are particularly useful.
  • Such acidic materials are typically positioned in layers on the receiving sheet below the dye developer reception layer, there suitably being a spacer layer between the acid layer and the mordanting layer to control the release of acidic material.
  • Such acidic materials serve to neutralize residual portions of the alkaline activator on the receiving sheet.
  • a wide variety of nonditfusible cationic or basic dye-mordanting compounds can be used in liquid permeable reception layers including amines such as polymeric amines, quaternary ammonium compounds, quaternary phosphonium compounds and tertiary sulfonium compounds.
  • Such mordants are nondiffusible in the alkaline processing composition and contain at least one hydrophobic ballast group.
  • either or both of the onium compounds and colorless hydroquinones can be incorporated on the receiving sheets.
  • the long chain bis-benzothiazolium salts of the present invention may also be provided in the reception element.
  • integral reception layers for dye developer images can also be utilized.
  • Such integral reception layers can be coated beneath the emulsion and dye developer layers near the support.
  • a stripping layer coated over the integral reception layer can be used to facilitate the removal of the over-coated layers after the ditfusion of the dye developer images to the reception layer.
  • the processing compositions or activators used to initiate development of the exposed light-sensitive elements in accordance with the invention are strongly alkaline.
  • the bis-benzothiazolium salts of the invention can be incorporated in these processing compositions.
  • Such processing compositions generally have a pH of at least 12 or contain at least .01 N hydroxyl ion.
  • Alkali metal hydroxides, such as sodium hydroxide, and sodium carbonate, are advantageously used in the composition for imparting such high alkalinity.
  • volatile amines such as diethyl amine can also be used, such amines having the advantage of being volatilized from the prints to leave no residue of alkali.
  • the colorless hydroquinone derivatives are preferably not used in the processing composition although when the pyridinium salts are present improved results are obtained.
  • processing compositions are generally aqueous liquids or solutions, and, as previously mentioned, when utilized in rupturable pods for in-camera processing such as described in US. 'Patent 2,435,717, generally contain thickening agents such as hydroxyethyl cellulose or carboxymethyl cellulose. Thickened processing compositions typically have viscosities of at least 5,000 cps. to 100,000 or even 200,000 cps.
  • a sensitive element is prepared by coating a subbed film support comprising cellulose acetate with suitably hardened genatin layers as follows:
  • Cyan dye developer layer An aqueous gelatin containing the cyan dye developer 5,8-dihydroxy-1,4-bis[(fl hydroquinonyl c methyl) ethylamino] anthraquinone is dissolved in a mixture of N-n-butylacetanilide, 4-methyl cyclohexanone and dispersing agent Alkanol B. The mixture is passed through a colloid mill several times, coated on the subbed support and dried so as to volatilize the 4-methyl cyclohexanone.
  • Red-sensitive emulsion layer A gelatino silver bromoiodide emulsion layer, which is sensitized to the red region of the spectrum is coated upon the cyan dye developer layer.
  • Magenta dye developer layer An aqueous gelatin solution containing the magenta dye developer 2[p-(2',S-dihydroxyphenethyl) phenylazo]-4-n-propoxy-1-naphthol is dissolved in a mixture of cyclohexanone, N n-butylacetanilide and Alkanol B is passed through a colloid mill several times, coated on the interlayer and dried to volatilize the cyclohexanone.
  • Green-sensitive emulsion layer A green-sensitive silver bromoiodide emulsion is coated on the magenta layer.
  • Interlayer A second gelatin interlayer is coated onto the greensensitive emulsion layer.
  • Blue-sensitive emulsion layer A blue-sensitive silver bromoiodide emulsion is coated onto the yellow dye developer layer.
  • Overcoat layer A final gelatin emulsion overcoat layer containing 4'- methylphenylhydroquinone is provided on the foregoing layers.
  • a sample of the freshly coated film is exposed under a step tablet through red, green and blue filters and is processed at a temperature of 12 F. with a processing solution disposed in a processing pod and having the composition set forth in Table 1 below:
  • the exposed film is processed at a gap of 0.004 inch (corresponding to the thickness of the activator layer) in contact with a color receiving sheet.
  • the receiving sheet is a white pigmented cellulose acetate butyrate support carrying a gelatin layer containing a mixture of poly-4-vinyl pyridine mordant and 1-phenyl-5-mercapto tetrazole.
  • the cyan, magenta and yellow dye developer images transfer from the undeveloped regions to the receiving sheet.
  • a monochromatic dye developer photosensitive element is prepared by coating a subbed film support comprising cellulose acetate with suitably hardened gelatin layers as follows.
  • magenta dye developer layer An aqueous gelatin solution containing the magenta dye developer 2[p-2,5-dihydroxyphenethyl)-phenylazo]- 4-n-propoxy-l-naphthol is dissolved in a mixture of cyclohexanone, N-n-butylacetanilide and Alkanol B is passed through a colloid mill several times, coated on the subbed support and dried to volatilize the cyclohexanone.
  • Green-sensitive emulsion layer A green-sensitive silver bromoiodide emulsion is coated on the magenta layer.
  • Overcoat layer A gelatin emulsion overcoat layer containing 4'-methylphenylhydroquinone is provided on the foregoing silver halide layer.
  • Samples of the freshly coated film are exposed under a green filter and are processed at temperatures of about 72 F. and 110 F., respectively, with a processing solution disposed in a processing pod and having the composition set forth in Table 1 above.
  • the exposed films are processed at a gap of 0.004 inch in contact with color receiving sheets similar to those of the previous examples.
  • the magenta dye developer images transfer from the undeveloped regions to the receiving sheets. This procedure is repeated for comparative purposes while employing various stabilizing agents and the long chain salts of the present invention in the magenta dye developer layer of each negative. The results are set forth below in Table 3.
  • a process for producing a photographic transfer image which comprises processing an exposed photosensitive element comprising at least one light-sensitive silver halide emulsion layer, and a dye developer which is both a silver halide developing agent and a dye contiguous to the silver halide of said silver halide emulsion layer, said processing being effected by treating said photographic element with an alkaline solution, developing a latent image in the regions of exposure of said silver halide layer and thereby immobilizing said dye developer in said regions of exposure, dye developer in undeveloped regions diffusing imagewise in register to a dye developer reception layer, the improvement which comprises effecting said processing in the presence of a bis-benzothiazolium salt wherein two benzothiazolium salt groups are joined, at the respective heterocyclic nitrogen atoms thereof, by a long chain alkylene group.
  • the photosensitive element comprises superposed red, green and blue lightsensitive silver halide emulsion layers and a dye developer contiguous to the silver halide of each of said layers.
  • R represents a member selected from the group consisting of a hydrogen atom and a lower alkyl group
  • D represents the non-metallic atoms necessary to complete a benzene nucleus
  • n represents a positive integer gen atoms thereof, my a long chain alkylene group.
  • a photographic element comprising at least one light-sensitive silver halide emulsion layer, and a dye developer which is both a silver halide developing agent and a dye contiguous to the silver halide of said silver halide emulsion layer, said element having incorporated in at least one hydrophilic colloid layer thereof a bisbenzothiazolium salt wherein two benzothiazolium salt groups are joined, at the respective heterocyclic nitrogen atoms thereof, by a long chain alkylene group.
  • a photographic element of claim 8 which comprises superposed red, green and blue light-sensitive silver halide emulsion layers and a dye developer contiguous to the silver halide of each of said layers.
  • a photographic element of claim 8 wherein said bis-benzothiazolium salt has the formula:
  • R represents a member selected from the group consisting of a hydrogen atom and a lower alkyl group
  • D represents the non-metallic atoms necessary to complete a benzene nucleus
  • n represents a positive integer of from 6 to 26
  • X represents an acid anion.
  • a photographic element of claim 8 wherein said bis-benzothiazolium salt is a decomethylene-bis-benzothiazolium salt.
  • a photographic product composed of a photosensitive element comprising at least one light-sensitive silver halide emulsion layer and a dye developer which is both a silver halide developing agent and a dye contiguous to the silver halide of said silver halide emulsion layer, a dye developer reception layer, said photosensitive element and said dye developer reception layer being capable of being superposed .on each other, and a bis-benzothiazolium salt wherein two benzothiazolium salt groups are joined, at the respective heterocyclic nitrogen atoms thereof, by a long chain alkylene group, said salt being so positioned in said product as to be present during the processing of said photosensitive element.
  • R represents a member selected from the group consisting of a hydrogen atom and a lower alkyl group
  • D represents the non-metallic atoms necessary to complete a benzene nucleus
  • n represents a positive integer of from 6 to 26
  • X represents an acid anion.
  • the photographic product of claim 13 which includes a rupturable container containing said salt and an alkaline processing composition for initiating development of said photosensitive element after exposure thereof.
  • R represents a member selected from the group consisting of a hydrogen atom and a lower alkyl group
  • D represents the non-metallic atoms necessaryy to complete a benzene nucleus
  • n represents a positive integer of from 6 to 26
  • X represents an acid anion.

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4057425A (en) * 1975-07-16 1977-11-08 Polaroid Corporation 2-Substituted benzimidazoles in multicolor diffusion transfer
JPS549058B1 (enrdf_load_stackoverflow) * 1971-04-19 1979-04-20

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2403927A (en) * 1942-12-03 1946-07-16 Ilford Ltd Improvers for photographic emulsions
US2673149A (en) * 1951-10-17 1954-03-23 Eastman Kodak Co Quaternary salts in mixed grain photographic emulsions
US2694716A (en) * 1951-10-17 1954-11-16 Eastman Kodak Co Polymethylene-bis-benzothiazolium salts
US3148062A (en) * 1959-04-06 1964-09-08 Eastman Kodak Co Photographic elements and processes using splittable couplers
US3189453A (en) * 1961-08-25 1965-06-15 Eastman Kodak Co Photographic emulsions containing thio derivatives as fixers and method of using same
US3206310A (en) * 1961-08-25 1965-09-14 Eastman Kodak Co Modification of colloidal metals and metal sulfides to reduce action as a nucleus for physical development
US3342596A (en) * 1964-03-11 1967-09-19 Eastman Kodak Co Benzothiazolium compounds for controlling overdevelopment

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2403927A (en) * 1942-12-03 1946-07-16 Ilford Ltd Improvers for photographic emulsions
US2673149A (en) * 1951-10-17 1954-03-23 Eastman Kodak Co Quaternary salts in mixed grain photographic emulsions
US2694716A (en) * 1951-10-17 1954-11-16 Eastman Kodak Co Polymethylene-bis-benzothiazolium salts
US3148062A (en) * 1959-04-06 1964-09-08 Eastman Kodak Co Photographic elements and processes using splittable couplers
US3189453A (en) * 1961-08-25 1965-06-15 Eastman Kodak Co Photographic emulsions containing thio derivatives as fixers and method of using same
US3206310A (en) * 1961-08-25 1965-09-14 Eastman Kodak Co Modification of colloidal metals and metal sulfides to reduce action as a nucleus for physical development
US3342596A (en) * 1964-03-11 1967-09-19 Eastman Kodak Co Benzothiazolium compounds for controlling overdevelopment

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS549058B1 (enrdf_load_stackoverflow) * 1971-04-19 1979-04-20
US4057425A (en) * 1975-07-16 1977-11-08 Polaroid Corporation 2-Substituted benzimidazoles in multicolor diffusion transfer

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GB1246658A (en) 1971-09-15

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