US3342598A - Phosphorous and maleic acid buffers for ferricyanide photographic bleaches - Google Patents

Phosphorous and maleic acid buffers for ferricyanide photographic bleaches Download PDF

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Publication number
US3342598A
US3342598A US463698A US46369865A US3342598A US 3342598 A US3342598 A US 3342598A US 463698 A US463698 A US 463698A US 46369865 A US46369865 A US 46369865A US 3342598 A US3342598 A US 3342598A
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Prior art keywords
bleach
acid
silver
ferricyanide
water
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Expired - Lifetime
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US463698A
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English (en)
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Charleton C Bard
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Eastman Kodak Co
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Eastman Kodak Co
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Priority to US463698A priority Critical patent/US3342598A/en
Priority to BE682166D priority patent/BE682166A/xx
Priority to DE19661547703 priority patent/DE1547703A1/de
Priority to GB26560/66A priority patent/GB1146478A/en
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Publication of US3342598A publication Critical patent/US3342598A/en
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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
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
    • G03C7/42—Bleach-fixing or agents therefor ; Desilvering processes
    • G03C7/421—Additives other than bleaching or fixing 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
    • G03C5/40—Chemically transforming developed images
    • G03C5/44—Bleaching; Bleach-fixing

Definitions

  • an object of my invention to provide a novel class of buffers that are stable in photographic bleach solutions and that will buffer the solutions in a pH range of from about 6 to about 7, and which have an increased buifering capacity as the pH approaches 6 from a pH of 7.
  • Another object is to provide novel bleach compositions for preparing bleach solutions which are stable and which are strongly buffered in the pH range from about 6 to about 7, such that the buifering capacity of the said solution increases as the pH approaches 6.
  • Still another object is to provide a bleach step for a color photographic process utilizing my novel bleach solution, said bleach causing no dye or Prussian blue formation in the photographic element being processed.
  • the water-soluble salts of phosphorous acid used to advantage according to my invention include the alkali metal phosphites (e.g., sodium phosphite, potassium phosphite, lithium phosphite, etc.), ammonium phosphite, an alkali metal ortho phosphite (e.g., sodium ortho phosphite, potassium ortho phosphite, lithium ortho phosphite, etc.), ammonium ortho phosphite, an alkali metal acid phosphite (e.g., sodium acid phosphite, potassium acid phosphite, lithium acid phosphite, etc.), ammonium acid phosphite, etc.
  • alkali metal phosphites e.g., sodium phosphite, potassium phosphite, lithium phosphite, etc.
  • ammonium phosphite e.g., sodium acid
  • the Watersoluble salts of maleic acid include the alkali metal salts (e.g., monosodium maleate, disodium maleate, monopotassium maleate, dipotassium maleate, monolithium maleate, dilithium maleate, etc.), the monoand diammonium maleates, etc.
  • alkali metal salts e.g., monosodium maleate, disodium maleate, monopotassium maleate, dipotassium maleate, monolithium maleate, dilithium maleate, etc.
  • My bulfered bleach compositions and solutions are used advantageously for preparing a combined bleach-fix bath by adding a suitable silver salt complexing agent.
  • My bleach composition contains as the oxidizing agent a water-soluble ferricyanide, such as an alkali metal ferricyanide (e.g., potassium ferricyanide, sodium ferricyanide, lithium ferricyanide, etc.), ammonium ferricyanide, etc.
  • a water-soluble ferricyanide such as an alkali metal ferricyanide (e.g., potassium ferricyanide, sodium ferricyanide, lithium ferricyanide, etc.), ammonium ferricyanide, etc.
  • my buffers can be used to advantage over a wide range of concentrations depending upon the particular processing conditions, photographic materials, etc.
  • concentrations of buffer up to about g./l. are useful; however, usually a concentration up to 30 g./l. is preferred.
  • the oxidizing agent is used in the range of from about 5 g./l. to about 200 -g./l.
  • any of the known silver salt complexing agents can be used to advantage in my bleach compositions to make a blix composition.
  • the useful complexing agents include the water-soluble thiocyanates, such as, the alkali metal thiocyanates, ferric thiocyanate, etc. dithiosuberic acid, etc.
  • the alkali metal thiosulfates can be used; however, they are not prefer-red for use in a ferricyanide bleach because of the short life of farmers reducer formed.
  • the complexing agents can be used over a wide range of concentrations.
  • the watersoluble thiocyanates can be used to advantage at concentrations from about 40 to about grams per liter.
  • Dithiosuberic acid can be used to advantage at concentrations from about 20 to about 150 grams per liter. These materials can be preweighed and added dry to the dry bleach compositions. Sufficient dry material is included to produce a solution having the desired concentrations.
  • My bleach solution can contain any of the various addenda that are usually used in bleach solutions, including alkali metal halides (e.g., potassium bromide, sodium chloride, etc.), bleaching accelerators, such as hexyl Cellosolve, etc., potassium ferrocyanide, potassium persulfate, alkali metal nitrates, boric anhydride, borax, citric acid, monosodium phosphate, phosphoric acid, alkali metal hexametaphosphate, etc.
  • alkali metal halides e.g., potassium bromide, sodium chloride, etc.
  • bleaching accelerators such as hexyl Cellosolve, etc., potassium ferrocyanide, potassium persulfate, alkali metal nitrates, boric anhydride, borax, citric acid, monosodium phosphate, phosphoric acid, alkali metal hexametaphosphate, etc.
  • both phosphorous and maleic acids and their water-soluble salts are not only stable in the immediate bleach solutions but are stable in bleaches outside the invention using quinone as the oxidizing agent for example, or even using the dichromate ion as a bleach in the pH range of from 1 to 3.
  • the phosphorous acid has been found to be stable for several days and the maleic acid has been found to be stable for about a day.
  • Both the phosphorous and maleic acids and their water-soluble salts can be used to advantage to buffer alkali metal dichromate solutions in the pH range from about 6 to about 7, however, the dichromate ion is not a good oxidizing agent for silver at pHs much above'3.
  • My bleach compositions containing the water-soluble salts of either phosphorous or maleic acids are advantageously prepared and stored in the dry form for solution in water to prepare the bleach bath when needed for processing.
  • My dry bleach compositions are made to contain the necessary amount of material to produce a solution containing from about 5 to about 200 g./l. of one of my oxidizers and up to about 100 g./l. of one of my buffers, and where needed the desired amount of addenda.
  • the bleach baths employed according to my invention are used to advantage in any photographic process in Which silver images are present in a photographic layer together with dye images.
  • the dye images may be those formed by color development as described in Mannes et al. U.S. Patents 2,252,718, 2,113,329 and 2,304,940 or the Jelley and Vittum US. Patent 2,322,027. These dyes are of the azomethine, indoaniline or indophenol type.
  • the dyes may also be azo dyes such as those used in the silver dye bleach process of color photography.
  • Example 1 Conventional multilayer, multicolor reversal film that contained incorporated color-forming couplers and which had been image exposed, processed through conventional formalin prehardener, acetic acid neutralizer, hydroquinone type negative developer, first stop bath, reversal bath, primary aromatic amino color developer, second stop bath was bleached in a solution having the following composition:
  • the example was repeated using a bleach outside my invention having the same formula except that 1 gram per liter of borax was substituted for the phosphorous acid.
  • the bleach bath pH which was about 7.0 as mixed tended to go below 6 during continuous processing and objectionable Prussian blue stain was produced on the processed film.
  • Example 2 Conventional multilayer, multicolor reversal film that did not contain any incorporated color-forming couplers which had been image exposed and processed through a conventional color process including the steps of prehardening, negative development, selective re-exposure of the bottom red-sensitive layer, cyan color development, selective re-exposure of the top blue-sensitive layer, yellow color development, fogging of the middle greensensitive layer, magenta color development with the usual intermediate water washes, was bleached in my bleach solution buffered with phosphorous acid and described in Example 1, then fixed in a conventional sodium thiosulfate fix bath. The processed film was of good quality and showed no evidence of unbleached silver or Prussian blue stain. The bleach bath pH showed good stability during a period of continuous processing with replenishment.
  • the example was repeated using a bleach outside my invention having the same formula except that 1 gram per liter of borax was used in place of the phosphorous acid.
  • the pH tended to go below 6 during continuous processing with the formation of objectionable Prussian blue stain on the processed film.
  • Example 3 A conventional multilayer multicolor reversal paper that contained incorporated color-forming couplers was exposed to a color image then given conventional color processing through a 1st MQ negative developer, 1st acid stop bath, re-exposure, a primary aromatic amino color developer, a hardener stop bath, then bleached in a solution having the formula:
  • the processed paper prints had good quality and were free of Prussian blue stains.
  • the bleach bath pH level was stable during continuous processing never going below a pH of 6.3 indicating good buffering from the phosphorous acid in my bleach.
  • Paper prints processed as in Example 3 but bleached in a bleach bath containing no phosphorous acid were found to have objectionable Prussian blue stain and the pH dropped to about 4.5.
  • Example 4 Similar good results were obtained by repeating Example 3 using 10 g./l. of maleic acid in my bleach in place of phosphorous acid. Silver bleaching was complete and there was no Prussian blue stain formed in the processed paper prints. The pH of the bleach bath never Went below 6.3 during continuous processing conditions.
  • Results similar to those obtained from use of my bleach solutions in Examples 1, 2 and 3 are obtained when up to 100 grams per liter of phosphorous acid or a water soluble salt of phosphorous acid, such as, an alkali metal (or ammonium) salt including, for example, sodium phosphite, potassium ortho phosphite, sodium acid phosphite, etc., is used as the buffer in my bleach.
  • an alkali metal (or ammonium) salt including, for example, sodium phosphite, potassium ortho phosphite, sodium acid phosphite, etc.
  • the alkali metal ferricyanide can be used to advantage over a range of from about 5 to about 200 grams per liter in my bleach baths.
  • a bleach such as that used in Example 1 containing phosphorous acid can be mixed using in place of the g./l. of sodium ferricyanide about 182 g./l. of sodium ferrocyanide decahydrate and 48 g./1. of potassium persulfate.
  • the required sodium ferricyanide is prepared by oxidation of sodium ferrocyanide with potassium persulfate without oxidizing the phosphorous acid.
  • Example 5 Blix baths having the typical compositions given below are used to advantage to bleach and fix in one step, conventional color film and color paper which have been given color processing up to the bleach step.
  • the accompanying drawing still further illustrates my invention.
  • the drawing shows curves A and B which show the butter capacity vs. pH for 0.05 M potassium acid phosphite and for 0.05 M potassium acid phosphate, respectively.
  • the buffer capacity is the number of gram equivalents of a strong acid that are required to decrease the pH one unit in one liter of solution, assuming no volume change.
  • Curve B shows that the solution of potassium acid phosphate has a sharply decreasing buffer capacity as the pH is lowered below about 6.75, and that a bleach solution containing ferricyanide ion and this material as the buffer would tend to form Prussian blue stain.
  • My bleach compositions containing phosphorous acid, a water-soluble salt of phosphorous acid, maleic acid or a water-soluble salt of maleic acid as the buffer are valuable for preparing bleach baths for photographic processing of color films and papers.
  • a dry composition for preparing a buffered bleach solution that is strongly buffered in the 6 to 7 pH range with increasing buffer capacity as the pH is forced toward 6, for use in a silver halide photographic process in which a silver image is present comprising:
  • a water-soluble ferricyanide (1) a water-soluble ferricyanide and (2) a buffer selected from the class consisting of phosphorous acid, water-soluble salts of phosphorous acid, maleic acid and water-soluble salts of maleic acid.
  • sufiicient buffer selected from the class consisting of phosphorous acid, water-soluble salts of phosphorous acid, maleic acid and water-soluble salts 6 of maleic acid to produce a solution containing up to about grams per liter.
  • composition for preparing a buffered bleach solution that is strongly buflered in the 6 to 7 pH range with increasing buffer capacity as the pH is forced to Ward 6, for use in a silver halide photographic process in which a silver image is present, said composition comprising:
  • composition for preparing a buffered bleach solution that is strongly buffered in the 6 to 7 pH range With increasing buffer capacity as the pH is forced toward 6, for use in a silver halide photographic process in which a silver image is present comprising:
  • sufiicient potassium ferricyanide to produce a solution containing from about 5 to about 200 grams per liter
  • a composition for preparing a buffered bleach solution that is strongly buffered in the 6 to 7 pH range with increasing buffer capacity as the pH is forced toward 6, for use in a silver halide photographic process in which a silver image is present comprising:
  • suflicient potassium ferricyanide to produce a solution containing from about 5 to about 200 grams per liter
  • a buffer selected from the class consisting of phosphorous acid, water-soluble salts of phosphorous acid, maleic acid and Water-soluble salts of maleic acid.
  • sufiicient buffer selected from the class consisting of phosphorous acid, water-soluble salts of phosphorous acid, maleic acid, and water-soluble salts of maleic acid to produce a solution containing up to about 100 grams per liter.
  • a dry composition for preparing a buffered blix solution that is strongly buffered in the 6 to 7 pH range with increasing buffer capacity as the pH is forced toward 6, for use in a silver halide photographic process in which a silver image is present comprising:
  • sufiicient potassium ferricyanide to produce a solution containing from about 5 to about 200 grams per liter
  • pH is gtorcedj toward 6, for use 'in asilver halide I 1 I I s 1 1 (1) sufficient potassium ferrioyanide; toproduce ;a so 1' photographic; process; in which a silver image is present, 1 I 1; 1 I 1 I i I lution: containing from about 51to about: ZOO'gi-ains I 1 1 said solution; Qorfnpris 1 7 f 1 /lg; of potassium I ferri I I i For liter, 1 1 I I I I I I I cyanide, 9o g./i. or dithios'uberic' acid, and 30 g.
  • the improvement I I 1 a d 1 g 7 comprising theuse 1n the said bleaching ⁇ step oiaibutfe'red 1' I I 1 1 1 1 j bieach solutio that is strongly buffered in e' 6 to 7 i 1 d a h 1 25' 1 11-1; range fWitlf'l: increasing?
  • buffer ⁇ capacity as he pH; is I 1 I 1 Z 1 1 5' 1 i7 :pfl;r g 1 j I f forced toward 6, said solution comprising; 11 1; I I I 1' 1E I 1' -1 1 ced toward I i I (11;) i fr m ab u j a ou .00 grams Pe liter o 1 1 T water-soluble ferricyanide; 1 and 1 1 .1 1 Z 1 i E 1 l 1 j 1 1 1 1 II I i (2) to about 100 grams per liter of ai buffer se- 1 looted firornfthe class consisting of pho phorous acid, 1 water-soluble salts?
  • aqueous bleach solution that is strongly buttered in the 6 to 7 pH range with increasing buffer References Cited gapaicity as the pH is forced toward 6, for use in a silver UNI STATES PATENTS ai e photographic process in which a silver image is present, said composition comprising 85 g./l. of sodium g i 9660 ferricyanide and 30 g./l. of phosphorous acid. e Wfir 96 6o 14.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
US463698A 1965-06-14 1965-06-14 Phosphorous and maleic acid buffers for ferricyanide photographic bleaches Expired - Lifetime US3342598A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US463698A US3342598A (en) 1965-06-14 1965-06-14 Phosphorous and maleic acid buffers for ferricyanide photographic bleaches
BE682166D BE682166A (enrdf_load_stackoverflow) 1965-06-14 1966-06-06
DE19661547703 DE1547703A1 (de) 1965-06-14 1966-06-13 Verfahren zum Abpuffern von Bleichbaedern fuer das farbphotographische Entwicklungsverfahren
GB26560/66A GB1146478A (en) 1965-06-14 1966-06-14 Photographic processing

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US463698A US3342598A (en) 1965-06-14 1965-06-14 Phosphorous and maleic acid buffers for ferricyanide photographic bleaches

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BE (1) BE682166A (enrdf_load_stackoverflow)
DE (1) DE1547703A1 (enrdf_load_stackoverflow)
GB (1) GB1146478A (enrdf_load_stackoverflow)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3856524A (en) * 1971-10-14 1974-12-24 Eastman Kodak Co Photographic elements and processes for providing tanned image records
US5716767A (en) * 1995-12-29 1998-02-10 Agfa-Gevaert Ag Bleaching bath for photographic black-&-white material
US6113665A (en) * 1994-02-07 2000-09-05 The Regents Of The University Of California Formulation of phosphorus fertilizer for plants
US6455236B1 (en) * 2000-01-06 2002-09-24 Trebla Chemical Company One-part bleach-fix liquid concentrates
US20060084573A1 (en) * 2004-10-12 2006-04-20 Biagro Western Sales, Inc. High calcium fertilizer composition
US20060283223A1 (en) * 2005-05-23 2006-12-21 Plant Protectants, Llc Dithiocarbamates and phosphite formulations
US11446508B2 (en) 2019-09-19 2022-09-20 Biotronik Se & Co. Kg Implantable medical device configured to establish a communication link to another implantable medical device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1950903A (en) * 1929-06-27 1934-03-13 Eastman Kodak Co Controlled reduction of photographic images
US2943935A (en) * 1957-05-15 1960-07-05 Gen Aniline & Film Corp Stabilization of photographic bleach powders containing an alkali metal ferricyanide

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1950903A (en) * 1929-06-27 1934-03-13 Eastman Kodak Co Controlled reduction of photographic images
US2943935A (en) * 1957-05-15 1960-07-05 Gen Aniline & Film Corp Stabilization of photographic bleach powders containing an alkali metal ferricyanide

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3856524A (en) * 1971-10-14 1974-12-24 Eastman Kodak Co Photographic elements and processes for providing tanned image records
USRE41789E1 (en) 1994-02-07 2010-10-05 The Regents Of The University Of California Formulation of phosphorus fertilizer for plants
US6113665A (en) * 1994-02-07 2000-09-05 The Regents Of The University Of California Formulation of phosphorus fertilizer for plants
US6645268B2 (en) 1994-02-07 2003-11-11 The Regents Of The University Of California Formulation of phosphorus fertilizer for plants
US20050126239A1 (en) * 1994-02-07 2005-06-16 The Regents Of The University Of California Novel formulation of phosphorus fertilizer for plants
US6929673B1 (en) 1994-02-07 2005-08-16 The Regents Of The University Of California Formulation of phosphorus fertilizer for plants
US20050178178A1 (en) * 1994-02-07 2005-08-18 The Regents Of The University Of California Novel formulation of phosphorus fertilizer for plants
USRE43073E1 (en) 1994-02-07 2012-01-10 The Regents Of The University Of California Formulation of phosphorus fertilizer for plants
US7160349B2 (en) 1994-02-07 2007-01-09 The Regents Of The University Of California Formulation of phosphorus fertilizer for plants
US7160350B2 (en) 1994-02-07 2007-01-09 The Regents Of The University Of California Formulation of phosphorus fertilizer for plants
US5716767A (en) * 1995-12-29 1998-02-10 Agfa-Gevaert Ag Bleaching bath for photographic black-&-white material
US6455236B1 (en) * 2000-01-06 2002-09-24 Trebla Chemical Company One-part bleach-fix liquid concentrates
US20060084573A1 (en) * 2004-10-12 2006-04-20 Biagro Western Sales, Inc. High calcium fertilizer composition
US7708799B2 (en) 2005-05-23 2010-05-04 Plant Protectants, Llc Dithiocarbamates and phosphite formulations
US20110021349A1 (en) * 2005-05-23 2011-01-27 Plant Protectants, Llc Dithiocarbamates and phosphite formulations
US20060283223A1 (en) * 2005-05-23 2006-12-21 Plant Protectants, Llc Dithiocarbamates and phosphite formulations
US11446508B2 (en) 2019-09-19 2022-09-20 Biotronik Se & Co. Kg Implantable medical device configured to establish a communication link to another implantable medical device

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GB1146478A (en) 1969-03-26
BE682166A (enrdf_load_stackoverflow) 1966-11-14
DE1547703A1 (de) 1969-12-18

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