US3515556A - Photographic developing process utilizing hemlock tannin polymer - Google Patents

Photographic developing process utilizing hemlock tannin polymer Download PDF

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Publication number
US3515556A
US3515556A US657540A US3515556DA US3515556A US 3515556 A US3515556 A US 3515556A US 657540 A US657540 A US 657540A US 3515556D A US3515556D A US 3515556DA US 3515556 A US3515556 A US 3515556A
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Prior art keywords
processing
solution
photographic
dispersing agent
processed
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US657540A
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Harold D Russell
Charles F Amering
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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
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
    • G03C5/29—Development processes or agents therefor
    • G03C5/305—Additives other than developers
    • G03C5/3053—Tensio-active agents or sequestering agents, e.g. water-softening or wetting agents
    • 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
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
    • G03C5/29—Development processes or agents therefor
    • G03C5/305—Additives other than developers

Definitions

  • This invention relates todispersing agents in photographic processes and compositions.
  • One aspect of the invention relates to photographic processing with photographic compositions, especially photographic aqueous processing solutions, containing a member of a class of polyphenolic compounds which are hemlock tannin polymers.
  • Another aspect relates to a continuous process employing such processing compositions in continuous transport processing apparatus.
  • image-recording systems use image-formlng materials comprising a support with one or more layers comprising hydrophilic colloid materials such as gelatin. Since the advent of film processing by film transport machines, as described for example in US. Pat. 3,023,779, the processing of such image recording systems has encountered particular problems in the form of unwanted markings on the processed elements. These markings occur in a definite line pattern at a fixed distance from the leading edge of a photographic element or sheet undergoing processing. When processing film, for example, in a roller transport machine having many rollers of the same diameter, this effect from each roller will occur at the same point on the film and will be cumulative.
  • markings have been shown to be of two types.
  • One type results due to simple dirt deposition, herein referred to as a simple pi line
  • the other type has been found to be due to density variations in the developed silver.
  • This latter type of marking is herein referred to as a chemical pi line.
  • the simple pi lines can be removed by buffing, but no process or composition heretofore has been satisfactory for preventing formation of chemical pi lines resulting from the density variation of silver. Attempts up to the present time have not been satisfactory for removing these markings either.
  • the efforts to prevent formation of chemical pi lines have included addition of coating aids or surfactants to the hydrophilic colloid layers of a photographic element.
  • the surfactants used often influence characteristics other than the coating performance of such layers, such as surface roughness, permeability of processing solutions, and the like.
  • saponin has been employed as a coating aid for photographic elements; but, when such elements are processed through continuous transport processing machines, such as a roller transport processor, as illustrated in US. Pat. 3,023,779, objectionable foaming occurs in the washing section of the machine. This foam tends to adhere to the surface of the processed photographic element causing objectionable marks.
  • Example 6 Various types of dispersing agents and surfactants have been added to processing solutions, but, as demon strated in following Example 6, have not been satisfactory for removing the undesired markings. Moreover, increasing the amounts of such dispersing agents or surfactants used does not provide the desired results. This is also demonstrated in Example 6.
  • the invention comprises a method of processing an exposed photographic element having at least one silver halide emulsion layer employing a processing solution containing a dispersing agent comprising, in sulfonated form, a hemlock tannin polymer.
  • composition suitable for developing an exposed photographic element having at least one silver halide emulsion layer, containing a silver halide developing agent and a dispersing agent comprising, in sulfonated form, a hemlock tannin polymer.
  • composition suitable for processing an exposed photographic element having at least one silver halide emulsion layer, containing a silver halide processing agent, a coagulant for colloidal silver and a dispersing agent comprising, in sulfonated form, a hemlock tannin polymer.
  • Hemlock tannin polymers as employed herein refers to a class of polyphenolic compounds typically found in coniferous tree barks, such as in the bark of Western hemlock trees (T saga heterophyllw).
  • the class of polymers can be prepared by extraction with hot water (about 97 C.) from such tree barks. Polymers within this class and a suitable method for their preparation are set out, for example, in an article by H. L. Hergert, L. E. Van- Blarican, J. C. Steinberg and K. R. Grasy in Forest Products Journal, vol. XV, No. 11, November 1965, pp. 485-491.
  • Hemlock tannin polymers within the scope of the invention can also be prepared by the method set out in US. Pat.
  • the hemlock tannin polymers of the invention are typically in sulfonated form. That is, they contain at least one sulfonate group, typically an alkali metal sulfonate group, e.g. -SO Na or -SO K.
  • the hemlock tannin polymers can be sulfonatecl using a wide variety of sulfonation processes, such as set out in Noller, Chemistry of Organic Compounds, W. B. Saunders and Co., Philadelphia, 1952, including treating the hemlock tannin polymer with sodium sulfite or sulfuric acid.
  • the hemlock tannin polymers can contain at least one sulfonate group for each repeating unit of the polymeric material.
  • Especially suitable members of the class of hemlock tannin polymers are, in sulfonated form, copolymers of catechin:
  • the average molecular weight and number of repeating structural units is typically sufliciently high that the copolymers are solid; however, the number is not exactly known.
  • the molecular weights of the polymeric products of the invention are usually at least about 3,000 or more.
  • a useful commercially available dispersing agent within the scope of the invention is sold under the trade name of Rayflo-C, :by Rayonier, Incorporated, New York, NY.
  • This dispersing agent is a water soluble mixture of copolymers of catechin with leucocyanidin in sulfonated form. It is a red-brown, free-flowing powder having the following typical chemical characteristics:
  • the dispersing agent according to the invention can be suitably admixed, dissolved or incorporated in any suitable manner in an aqueous processing solution. It can be incorporated in the form of a dry powder, aqueous concentrate, dispersion, aqueous solution, or in other suitable forms.
  • the suitable concentrations of dispersing agent employed in a particular processing solution can vary and will be influenced by the particular ingredients of the processing solution, the temperature employed and other factors which can be determined by those skilled in the art.
  • An effective concentration of dispersing agent found suitable for a typical processing agent such as a developer, stabilizer, or fixer solution comprises about 0.001 to about 10 grams of dispersing agent per liter of solution containing the processing agent.
  • a particularly useful concentration is about 0.1 gram to about 1.0 gram of the dispersing agent per liter of processing solution.
  • An aqueous processing solution as employed herein refers to a wide range of aqueous solutions which are suitable for processing an exposed photographic emulsion. Such a solution is usually a developing, stabilizing or fixing composition, but, other processing solutions are suitable. Typical processing solutions and their components are disclosed, for example, in Mees, Theory of the Photographic Process, 3rd ed., Macmillan Company, New York, NY. (1966).
  • a typical developer solution within the scope of the invention comprises an aqueous solution of a silver halide developing agent, an activator, e.g. an alkali metal hydroxide, and a minor proportion, e.g. about .001 to about 10 grams per liter of solution, of a hemlock tannin polymer in sulfonated form.
  • an activator e.g. an alkali metal hydroxide
  • a minor proportion e.g. about .001 to about 10 grams per liter of solution, of a hemlock tannin polymer in sulfonated form.
  • a typical fixing or stabilizing solution within the scope of the invention comprises an aqueous solution of a silver halide fixing agent or a silver halide stabilizing agent, and a minor proportion, e.g. about .001 to about 10 grams per liter of solution, of a hemlock tannin polymer in sulfonated form.
  • Such processing compositions are especially suitable for processing a photographic element having at least one silver halide emulsion layer wherein the element is processed in one continuous motion by transporting it into and out of at least one of such processing solutions containing the described hemlock tannin polymers.
  • Suitable apparatus and processing steps are set out, for example, in US. Pats. 3,025,779- Russell et al., issued Mar. 20, 1962; 3,078,024-Sardeson, issued Feb. 19, 1963; 3,122,086Fitch, issued Feb. 24, 1964; 3,149,551-Cramer, issued Sept. 22, 1964; 3,156,- 173--Meyer, issued Nov. 10, 1964; and 3,224,356- Fleisher et a1., issued Dec. 21, 1965.-
  • Coagulant as employed herein is intended to refer to compounds which cause the colloidal silver particles in a photographic processing solution to agglomerate or otherwise form larger particles which can be filtered.
  • suitable coagulants are coagulant thiol compounds, that is, coagulant compounds represented by the structure R-fiSH, wherein R is a hydrocarbon radical such as an alkyl, e.g.
  • the effectiveness of this action caused by the dispersing agent of the invention, and especially by the combination of the dispersing agent with a coagulant, extends for a significant period of use, e.g. several weeks, and is particularly long-lasting when solutions are filtered to remove particles which adversely affect the processed film.
  • the amount of coagulant employed can vary depending upon components of the processing solution, temperature, and the like. Typically, about .01 to about 1.0% by weight of coagulant of the total processing solution is suitable.
  • the developing agents useful in composition of the invention include any silver halide developing agents.
  • Suitable developing agents include polyhydroxybenzene developing agents, e.g. hydroquinone developing agents such as hydroquinone, alkyl substituted hydroquinones as exemplified by t-butylhydroquinone, methylhydroquinone, dimethylhydroquinone; catechol and pyrogallol; chloro substituted hydroquinones such as chlorohydroquinone or dichlorohydroquinone; alkoxy substituted hydroquinones such as methoxy or ethoxy hydroquinone; aminophenol developing agents such as 2,4-diaminophenols and methylaminophenols; ascorbic acid; pyrazolidone developing agents such as 1-phenyl-3-pyrazolidone, including those described in British Pat. 930,572; and acyl derivatives of p-aminophenol such as disclosed in British Pat. 1,045,303.
  • Such developing agents can be used alone or in
  • Concentrations of the silver halide developing agent can vary over a wide range. Suitable concentrations in a developer composition will be determined based on other components present, the desired image and other factors which can be determined by those skilled in the art.
  • Such developing agents can be present in one or more layers of the photographic elements processed.
  • Developer compositions of the invention typically contain an activator.
  • Any suitable development activator can be employed with the compositions of the invention, such as alkali metal hydroxides, e.g. sodium hydroxide, potassium hydroxide or lithium hydroxide, or other suitable alkaline materials such as organic amines. These can be used in any concentration which is effective for achieving the desired alkalinity.
  • the photographic emulsions useful according to the invention include a wide variety of silver halide emulsions. They can be non-spectrally sensitized emulsions,
  • photographic emulsions employed in the practice of the invention can be sensitized using any of the well known techniques in emulsion making, for example, by digesting with naturally active gelatin or various sulfur, selenium, noble metal and/or gold compounds.
  • the photographic emulsions processed according to the invention, and the compositions employed for processing, can contain various photographic addenda, especially those known to be beneficial in photographic compositions.
  • the types of addenda and concentrations to be employed can be determined by those skilled in the art.
  • Suitable photographic addenda include, for example, hardeners, e.g. alum, or those set out in British Pat. 974,- 317; buffers which maintain the desired pH level including various sulfonamides and boraxes; coating aides, coating aids, plasticizers; speed increasing addenda, such as quaternary ammonium salts and alkylene oxide polymers, e.g. polyethylene glycols; and stabilizing agents such as sodium sulfite.
  • the silver halides employed in the practice of the invention include any of the photographic silver halides, such as silver bromide, silver iodide, silver chloride, or mixed silver halides such as silver chlorobromide, silver bromoiodide and the like. Particularly good results are obtained with so-called high contrast photographic emulsions in which the halide comprises at least about 50 mole percent chloride.
  • the silver halides can be those which form latent images predominantly on the surface of the silver halide grains or those which form latent images inside the silver halide crystals, such as described in US. Pat. 2,592,250 Davey and Knott, issued Apr. 8, 1952.
  • the photographic elements processed according to the invention typically contain a layer comprising any of the known hydrophilic water permeable binding materials suitable for photographic purposes. These include, for example, gelatin, cellulose derivatives, polymerized vinyl compounds as well as mixtures of such binding agents.
  • the binding agents can also contain water insoluble polymers, such as polymerized ethylenically unsaturated compounds, e.g. polymers of acrylates and methacrylate.
  • compositions of the invention can have a wide range of pH values.
  • the developer compositions are typically employed at a pH above about 7, e.g. about 7 to about 14.
  • the appropriate pH value will be determined by the purpose of the processing composition, the desired degree of action, and the like.
  • the time for processing, such as development, fixing or stabilizing, employing the processes and compositions of the invention can vary between about a second up to about an hour or more, depending on the desired image, process ing conditions and the like.
  • Exposed sheets of film containing a silver halide gelatino emulsion of the type normally used in radiography are fed into a roller transport processor, as described in U.S. Pat. 3,023,779, wherein the transport of the sheets of film through the processing stages is accomplished by means of rollers which contact both sides of the film.
  • the developing solution which is employed in the processor consists of:
  • the film transported by the rollers is passed through a tank containing the developer solution, a fixing tank containing ammonium thiosulfate fixer, a water wash tank and then a drier section where the film is hot-air dried.
  • Sheets of film processed in this manner have horizontal lines of higher than background density a few inches in from the leading edge of the film and parallel to the leading edge.
  • a group of the same films identically exposed are processed employing the above developer solution with the exception that 0.5 gram per liter of solution of a hemlock tannin polymer, i.e., a mixture of copolymers of catechin with leucocyanidin in sulfonated form is added.
  • the unsulfonated form of this copolymer mixture is represented by the Structures III and IV.
  • the resulting developed film shows no horizontal lines. Even the very first sheets of film processed in the roller transport processor employing the solution containing the polyphenolic dispersing agent of the invention are free of horizontal lines or pi markings.
  • EXAMPLE 2 This example demonstrates the use of a dispersing agent of the invention in another developer composition.
  • Exposed sheets of film containing a silver halide gelatino emulsion of the type normally used in radiography are processed in a roller transport processor as set out in Example 1.
  • the developer solution employed in the processor consists of:
  • EXAMPLE 4 The process set out in Example 2 is repeated employing 10.0 grams per liter of the dispersing agent in the developer solution. Exposed film processed with this concentration of dispersing agent in the developer solution is free of pi line markings.
  • Example 2 The procedure set out in Example 2 is repeated. However, besides adding 0.25 gram of the dispersing agent per liter of developing solution, 0.25 gram of the dispersing agent per liter of solution is added to the ammonium thiosulfate fixing solution also employed during processing. The resulting processed film is free of any pi line markings.
  • EXAMPLE 6 This is a comparative example demonstrating that the dispersing agent of the invention provides unexpected properties and results over other wetting agents or surface active agents.
  • Example 2 a developer solution as described in Example 2 is prepared with the addition of other dispersant emulsifiers.
  • alkanolamide dispersing agents in a similar manner produces unsatisfactory results due to their effect on the sensitometric characteristics or fogging of the light sensitive films.
  • EXAMPLE 7 This example illustrates the use of a dispersing agent of the invention in combination with a colloidal silver coagulant in processing solutions.
  • Example 1 The procedure set out in Example 1 is repeated using the same developer solution with the exception that 1 part by volume of the dispersing agent and 1 part by volume cysteine are added per 1000 parts by volume of developer solution. This causes the suspended matter in the developer solution to form particles which are filterable from the developer solution. The minimum density of the photographic emulsion processed through this solution is significantly reduced.
  • a method comprising processing an exposed photographic element having at least one silver halide emulsion layer in a processing solution containing a dispersing agent comprising, in sulfonated form, a hemlock tannin polymer.
  • hemlock tannin polymer is a mixture of copolymers of catechin with leucocyanidin.
  • a process as in claim 1 wherein said mixture of hemlock tannin polymers is a mixture of copolymers of catechin with leucocyanidin having the following properties:
  • processing solution comprises a silver halide developer solution.
  • processing solution comprises a silver halide fixing solution.
  • a composition comprising a silver halide developing agent and a dispersing agent comprising in sulfonated form a hemlock tannin polymer.
  • composition as in claim 8 wherein said hemlock tannin polymer is a copolymer of catechin with leucocyanidin.
  • composition as in claim 8 wherein said dispersing agent comprises a mixture of copolymers of catechin with leucocyanidin having the following properties:
  • a composition as in claim 8 comprising an aqueous solution of about 0.001 to about 10 grams per liter of solution of hemlock tannin polymers.
  • a composition comprising a silver halide processing agent, a coagulant for colloidal silver and a dispersing agent comprising, in sulfonated form, a hemlock tannin polymer.
  • a composition as in claim 12 comprising an aqueous solution of a silver halide developing agent, a coagulant for colloidal silver, and a dispersing agent comprising in sulfonated form a copolymer of catechin with leucocyanidin.
  • composition as in claim 12 wherein said coagulant is cysteine, o-mercaptobenzoic acid or di-isobutyl phenoxyethoxy ethyl dimethyl ammonium chloride.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Separation Of Suspended Particles By Flocculating Agents (AREA)
US657540A 1967-08-01 1967-08-01 Photographic developing process utilizing hemlock tannin polymer Expired - Lifetime US3515556A (en)

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BE (1) BE718811A (enrdf_load_stackoverflow)
FR (1) FR1573784A (enrdf_load_stackoverflow)
GB (1) GB1225406A (enrdf_load_stackoverflow)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3928042A (en) * 1974-07-22 1975-12-23 Itt Preservatives for photographic developers
US4323642A (en) * 1981-03-09 1982-04-06 Eastman Kodak Company Stable photographic developers containing an indazole antifoggant and a lignosulfonate
US5830315A (en) * 1995-07-06 1998-11-03 Betzdearborn Inc. Treatment of Aqueous systems using a chemically modified tannin

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1388755B1 (en) * 2002-07-30 2006-03-01 Agfa-Gevaert Silver halide photographic processing solution
US6740479B2 (en) 2002-07-30 2004-05-25 Agfa-Gevaert Silver halide photographic processing solution
US9523172B2 (en) * 2011-07-18 2016-12-20 Lakeland Industries, Inc. Process for producing polyvinyl alcohol articles

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2533990A (en) * 1947-06-10 1950-12-12 Du Pont Silver halide developer compositions containing polyoxyalkylene ethers of hexitol ring dehydration products
US2782241A (en) * 1955-03-02 1957-02-19 Rayonier Inc Bark treatment process and product
US3007971A (en) * 1959-04-10 1961-11-07 Macmillan & Bloedel Ltd Process for recovering polyphenols
US3026264A (en) * 1960-07-11 1962-03-20 Shell Oil Co Substituted benzenes

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2533990A (en) * 1947-06-10 1950-12-12 Du Pont Silver halide developer compositions containing polyoxyalkylene ethers of hexitol ring dehydration products
US2782241A (en) * 1955-03-02 1957-02-19 Rayonier Inc Bark treatment process and product
US3007971A (en) * 1959-04-10 1961-11-07 Macmillan & Bloedel Ltd Process for recovering polyphenols
US3026264A (en) * 1960-07-11 1962-03-20 Shell Oil Co Substituted benzenes

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3928042A (en) * 1974-07-22 1975-12-23 Itt Preservatives for photographic developers
US4323642A (en) * 1981-03-09 1982-04-06 Eastman Kodak Company Stable photographic developers containing an indazole antifoggant and a lignosulfonate
US5830315A (en) * 1995-07-06 1998-11-03 Betzdearborn Inc. Treatment of Aqueous systems using a chemically modified tannin
US5843337A (en) * 1995-07-06 1998-12-01 Betzdearborn Inc. Treatment of aqueous systems using a chemically modified tannin
US5977287A (en) * 1995-07-06 1999-11-02 Betzdearborn Inc. Treatment of aqueous systems using a chemically modified tannin

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FR1573784A (enrdf_load_stackoverflow) 1969-07-04
BE718811A (enrdf_load_stackoverflow) 1968-12-31
GB1225406A (enrdf_load_stackoverflow) 1971-03-17

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