Classifications

• • 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
  • G03C5/395—Regeneration of photographic processing agents other than developers; Replenishers therefor
  • G03C5/3958—Replenishment processes or compositions, i.e. addition of useful photographic processing 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
  • 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
  • G03C7/44—Regeneration; Replenishers
• • 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
  • G03C5/264—Supplying of photographic processing chemicals; Preparation or packaging thereof
  • G03C5/266—Supplying of photographic processing chemicals; Preparation or packaging thereof of solutions or concentrates
• • 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

Definitions

• This invention concerns a method for replenishing a photographic fixing agent designed for the processing of photographic materials, particularly color processing. More specifically, the invention concerns a method to reduce the quantity of water necessary for the photographic processing, and thereby the quantity of effluent discarded from said processing, by adding to the fixing bath a concentrated replenishment solution (also called maintenance solution or regenerating solution) of a fixing agent.
• a concentrated replenishment solution also called maintenance solution or regenerating solution
• a fixing step is used to complex and thereby dissolve undeveloped silver halides remaining in the photographic material.
• a bleaching step is used in order to oxidize developed silver which is then fixed.
• the fixing step is accomplished with a fixing bath, which comprises a fixing agent, the most usual of which is thiosulfate, together with various other constituents.
• the sensitometric characteristics of the processed materials depend on the values of the process parameters; temperature, pH, and concentrations of the constituents. These parameters must therefore be monitored continuously. Because the processing itself also consumes the reagents initially supplied to the baths, these baths have to be maintained or replenished.
• the process manuals indicate replenishment bath formulations, in particular for developing and fixing baths. These replenishment baths are supplied systematically, after the developing bath has been in operation for a certain number of hours, or after a certain quantity of film has been processed, or continuously.
• Photographic processing comprises successive immersions in different baths separated by washing tanks. Such processing therefore consumes much water and generates much effluent that has to be treated before being recycled or discarded.
• the replenishment of such fixing baths is usually carried out using solutions prepared from kits comprising concentrates. These concentrates are diluted at time of use and then added to the fixing bath. The necessary replenishment of the baths further increases the water consumption and thereby the effluent produced.
• Many methods have been proposed for the treatment and(or) the recycling of the effluents.
• the present invention provides a solution to the problem of reducing the water consumption without adversely affecting the sensitometric results of the photographic process.
• the object of this invention is a method for the maintenance and replenishment of fixing baths using concentrated solutions.
• the method of the invention for the maintenance of a photographic fixing bath comprises the addition of a concentrated aqueous solution of a fixing agent to the fixing bath during the processing in a photographic processing.
• concentration solution mean a solution containing at least 200 g/l preferably at least 500 g and more preferably at least 800 g of 60 % ammonium thiosulfate per liter. A concentration of 800 g/l of 60 % ammonium thiosulfate corresponds to 3.25 mole/l.
• a further object of this invention is a method of photographic processing comprising at least one developing step and one fixing step wherein the fixing step is carried out using a fixing agent the maintenance of which is achieved using a concentrated solution.
• the fixing agents are well known, and are described for example in “ Chimie et Physique Photographiques " by P. Glafkidès, p.174 et seq., Ed. P. Montel, Paris, 4th edition, 1976.
• the most commonly used fixing agents are alkali metal or ammonium thiosulfates.
• the fixer can also comprise sulfite and(or) bisulfite, an anti-calcium agent, a buffer, etc.
• the pH of the fixing agent is generally between 5.5 and 7, and it must be strictly controlled to assure sensitometric quality, that is, maintaining sensitometric values such as speed, contrast, Dmin, Dmax with the ranges indicated in the processing manuals.
• this flow rate is more than 20 l/hour (i.e., given the run-through speed of the film, 1.33 l/100 m of 35 mm of motion picture film), it is possible with a concentrated solution to reduce this flow rate to 5 l/hour (0.33 l/100 m of 35 mm of film processed, such as 35 mm motion picture film), or even to 1 l/hour (0.07 l/100 m of 35 mm motion picture).
• the concentration of the thiosulfate replenishment solution can be in the range of from 0.8 to 5 mole/l and preferably of from about 2 to about 4 mole/l.
• This latter molar concentration represents from about 500 g/l to about 1000 g/l of a 60 weight % aqueous solution of ammonium thiosulfate.
• the concentrate can also contain all the components of an usual fixer replenisher, for instance sulfite, bisulfite, ammonia, a buffer, an anticalcium agent, a biocide, etc.
• fixer replenisher for instance sulfite, bisulfite, ammonia, a buffer, an anticalcium agent, a biocide, etc.
• the composition of the fixing bath used in the processing machine has to remain constant, for example 185 ml of 58% thiosulfate per liter and 20 g of sulfite per liter.
• flow rates are 185 x 20 ml for thiosulfate and 20 x 20 g for sulfite per hour.
• flow rates are only 185 ml for thiosulfate and 20 g for sulfite per hour, respectively.
• the method of the invention finds a particularly advantageous application in the processing of color motion picture films.
• Such processing concerns large quantities of film, and therefore large-sized machines that consume large quantities of water and solution, and generate large quantities of effluent waste.
• it is important to minimize the quantity of water used in such processing, while not adversely affecting the sensitometric values of the processed film.
• ECN® Eastman Color Negative film was processed using the process ECN-2.
• the initial fixing bath had the following composition, as prescribed in " Manual for Processing Eastman Motion Picture Film”, Module 7, Process ECN-2 specifications, EKC, 1990 page 24. Water 700 ml 59% Ammonium thiosulfate 185 ml Sodium sulfite 10 g Anhydrous sodium bisulfite 8.4 g pH at 27°C 6.5
• the replenishment of the fixing bath is usually carried out using a solution with the composition below, as prescribed by the Manual cited, this solution being added continuously.
• the concentrated solution detailed below was used: 59% Ammonium thiosulfate 861.86 g ANTICAL N° 8 anticalcium agent 32.9 g 43% Ammonium bisulfite 46.2 g Anhydrous sodium sulfite 154.2 g 20% Ammonia 25.74 g Acetic acid 8.55 g Water QSP 11
• the bromide and iodide levels remained stable within the tolerance limits of the ECN-2 process, i.e., less than 25 g/l of bromide and less than 2 g/l of iodide.
• the quantity of thiosulfate in the fixing bath was adjusted by regulating the flow rate of the replenishment solution. As prescribed for the ECN-2 process, the pH must not fall below 5.5, and when below this value, was readjusted to 6.5 with ammonium hydroxide. Likewise, the quantity of sulfite must not fall below 15 g/l of fixing bath, and when below this value, was readjusted to 20 g/l by adding sulfite. Sensitometric data were not modified.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Silver Salt Photography Or Processing Solution Therefor (AREA)

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Publications (1)

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Family Applications (1)

Country Status (3)

Citations (2)

• 1999
  • 1999-04-19 FR FR9905059A patent/FR2792423B1/fr not_active Expired - Fee Related
• 2000
  • 2000-03-24 EP EP20000420053 patent/EP1046952A1/en not_active Withdrawn
  • 2000-04-14 JP JP2000118518A patent/JP2000321737A/ja active Pending

Patent Citations (2)

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