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
  • G03C5/29—Development processes or agents therefor
  • G03C5/31—Regeneration; Replenishers

Definitions

• the present invention relates to a method for processing silver halide materials with a developing solution containing an ascorbic acid derivative and a 3-pyrazolidone derivative as developing agents and more particularly to a method of replenishment of such a developing solution.
• aqueous alkaline developer compositions containing a developing agent usually of the dihydroxybenzene type such as hydroquinone.
• US 2,688,549 discloses the combination of a 3-pyrazolidone developing agent and of an ascorbic acid derivative.
• GB 1 266 533 describes the combination of a p-hydroxybenzene developing agent, an ascorbic acid and sulphite ions.
• An equally good developing activity for both surface and internal latent images is claimed in US 3,826,654 which discloses a combination of a 3-pyrazolidone, an ascorbic acid, a heterocyclic thione or thiol and an alkali iodide at a pH of at least 12.
• US 3,942,985 discloses the combination of an iron chelate developer and an ascorbic acid derivative.
• US 4,756,997 claims a combination of a p-hydroxybenzene, an auxiliary developer, an anti-foggant, an antioxidant and an ⁇ -ketocarboxylic acid wherein the antioxidant can be ascorbic acid.
• the object of the present invention is realized by providing a method for processing with constant activity image-wise exposed silver halide photographic material comprising following steps :
• the ascorbic acid analogue or derivative represented by general formula (I) is l-ascorbic acid, iso-ascorbic acid or a salt thereof.
• the replenisher is added as a powder comprising substantially the same ingredients as the developer but having alkali in such an amount that the pH of the developer is maintained constant by adding this powder periodically to it.
• the replenisher is just one solution having a higher pH than the developer and having the same ingredients in the same or, if needed, in a different concentration.
• the replenishment can be performed by means of a single solution having a higher pH than the developing solution, two or more replenisher solutions from which at least one has a pH value higher than the developing solution, or by means of a powder composition containing alkali in such an amount that the pH of the developer is maintained constant by adding this powder periodically to it.
• the composition of this solution is the same as the composition of the developing solution, except for the alkali compound, or is formulated so that the concentration of the important components of the developer solution is readjusted to a constant starting value during processing, e.g. an increase in concentration by replenishment for developing agent and anti-fogging agent, and a decrease for halide ion.
• the minimal pH difference between replenisher and developer is about 0.2 units per g AgNO3 coated per sq.m. of which 50 % is developable, for a replenishment amount of 250 ml/m2.
• the optimal pH difference is about 0.7 ; e.g. the pH of the developer is 10.0 and the pH of the replenisher is 10.7.
• the ascorbic acid type developing agent can be represented by following general formula (I): wherein X represents an oxygen atom or an imino group, and n represents a positive integer from 1 to 4, and R represents a hydroxy group when n is 1, and R represents a hydroxy group or a hydrogen atom when n is 2 to 4.
• Preferred compounds for use in accordance with the present invention are l-ascorbic acid and iso-ascorbic acid.
• Other useful compounds include imino-l-ascorbic acid, 6-desoxy-l-ascorbic acid, l-rhamnoascorbic acid, l-fucoascorbic acid, d-glucoheptoascorbic acid, d-glucoascorbic acid, l-erythroascorbic acid, and their stereoisomers.
• the developing agents can be incorporated in the developing solution in the free acid form or as a salt, preferably an alkali salt.
• the ascorbic acid type developing agent is incorporated in the developer in a concentration ranging preferably between 0.1 and 0.8 mole/liter.
• concentration is preferably the same or up to 20 % higher than in the developer.
• the Phenidone type developing agent is incorporated in the developer in a concentration ranging preferably between 0.002 and 0.025 mole/liter.
• concentration is preferably the same or up to 20 % higher than in the developer.
• the developing and replenishing solutions preferably further contain an anti-fogging agent.
• Many known compounds can be added as fog-inhibiting agent or stabilizer to a processing solution. Suitable examples are e.g. the heterocyclic nitrogen-containing compounds such as benzothiazolium salts, nitroimidazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, aminotriazoles, benzotriazoles (preferably 5-methyl-benzotriazole), nitrobenzotriazoles, mercaptopyrimidines, mercaptotriazines, benzothiazoline-2-thione and oxazoline-thione.
• triazolopyrimidines such as those described in GB 1,203,757, GB 1,209,146, JA-Appl. 75-39537, and GB 1,500,278 and other compounds such as benzenethiosulphonic acid, benzenethiosulphinic acid and benzenethiosulphonic acid amide compounds.
• a preferred compound for use in accordance with the present invention is 1-phenyl-5-mercaptotetrazole.
• the developing and repleshing solutions for use in accordance with the present invention preferably further contain a compound providing halide ions as development rate regulator, most preferably sodium or potassium bromide in a concentration between 0.01 and 0.2 mole/liter.
• a compound providing halide ions as development rate regulator, most preferably sodium or potassium bromide in a concentration between 0.01 and 0.2 mole/liter.
• Further sulphite ions preferably provided as an alkali sulphite, are preferably present as antioxidant in a concentration between 0.1 and 0.5 mole/liter.
• the alkali agent is preferably sodium or potassium hydroxide.
• the developing and replenishing solutions for use in accordance with the present invention further contain buffering agents.
• Suitable buffer systems include carbonate buffer, phosphate buffer, metaborate buffer, etc.
• the concentration of these buffering agents is preferably about 0.4 mole/liter.
• the silver halide photographic materials which can be processed by the method of the present invention include all kinds of black-and-white materials, e.g. films and papers for amateur photography, films for cinematography, materials for radiographic recording and materials for graphic arts.
• the replenishment can be performed on a regular time interval basis and/or based on film throughput, pH-measurement, halide ion concentration measurement and density measurements on test strips.
• Replenishment of the developer solution was performed at the following rates : 250 ml of the replenisher were added per sq.m. of said film for compensation of developer exhaustion; an extra 250 ml of the replenisher were added per 24 h for compensation of aerial oxidation.
• Processing method A The composition of the developing solution (Da) was the same as the composition of the replenishing solution (Ra). This composition was : Water 600ml K2CO3 20g K2SO3 65g KBr 10g Sodium iso-ascorbate . 1 aq. 45g 1-phenyl-3-pyrazolidone 0.5g 1-phenyl-5-mercaptotetrazole 0.006g KOH 16.6g Water to 1 l.
• Processing method B the same processing method was used as method A, but both solutions contained a higher concentration of buffering agent and ascorbic acid developing agent.
• Processing method D the composition of the developing solution is the same as the composition of the replenishing solution.
• the replenishment amounted to 250 ml per sq.m. developed film.
• the composition of developer Dd and replenisher Rd was : Water 600ml K2CO3 61g K2SO3 65g KBr 10g Ascorbic acid 50g 1-phenyl-4-hydroxymethyl-4'-methyl-3-pyrazolidone 4.2g 1-phenyl-5-mercaptotetrazole 0.08g KOH 8.5g Water to 1 l.
• Processing method E replenishment was performed with a solution at a higher pH than the pH of the developing bath at an amount of 250 ml per sq.m. developed film.
• the compositions were : Composition of the developing solution De : Water 600ml K2CO3 61g K2SO3 65g KBr 10g Ascorbic acid 50g 1-phenyl-4-hydroxymethyl-4'-methyl-3-pyrazolidone 4.2g 1-phenyl-5-mercaptotetrazole 0.08g KOH 8.0g Water to 1 l.
• pH 10.10
• Processing method F the amount of replenishing solution per sq.m. developed film was decreased from 250 ml (processing method E) to 200 ml and the pH of the replenishing solution was incrased from 10.73 to 10.83.
• the compositions were : Composition of the developing solution Df : the same as De.

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

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Cited By (22)

Citations (4)

• 1992
  • 1992-06-09 EP EP92201656A patent/EP0573700A1/fr not_active Withdrawn

Patent Citations (4)

Non-Patent Citations (2)

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