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
  • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
  • G03C7/02—Direct bleach-out processes; Materials therefor; Preparing or processing such materials
• • 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
  • G03C7/28—Silver dye bleach processes; Materials therefor; Preparing or processing such materials

Definitions

• the present invention has for object improvements in the manufacture of photographic bleaching layers, said improvements being adapted-to improve the quality of said layers and their preserving capacity.
• bleaching layers in particular those which are prepared with sensitisers the action of which is sufilciently high for them to be used practically, as for instance certain thiocarbamic derivatives, and more particularly sensitisers which are soluble in water, such as they are defined in the French patent in the name of the applicants filed on March 16, 1938, for: Process i or the preparation of photographic bleaching layers and suitable sensitisers, can only be kept for a short time before being exposed to light. At the end of a greater or less period of time, a coloured .residue is formed in the layer which is no longer sensitive to light and does not become discoloured when exposed.
• a reversibility or bleaching after exposure is'noticed, particularly after wetting the prints with water or with other liquids (fixing liquids, etc.) or if the prints are allowed to stay in the air, or if they are exposed to heat.
• This recoloration takes place instantaneously when certain dyestuffs for instance oxazines, are used.
• acyl-amides As compounds suitable for the present process, there can be cited, by way of non limiting examples, acyl-amides, carbamides, sulphocarb'amides (except the known sensitisers) amidines,
• guanidines hydrazides, hydrazidines, acylhydroxamines, imi'doethers, various heterocyclic compounds, the formulaof which corresponds to the general formulae indicated, etc., as well as their derivatives and their salts.
• acid amides are especially suitable, in particular those which, by hygroscopicity, retain the dampness necessary for the satisfactory operation of the layer. Very good results have been obtained with acetamide.
• the simultaneous use of hygroscopic agents (such for instance as glycerol) is recommended.
• Example 1 The solution for the bleaching layer; is prepared by dissolving 1 gram of basic dye-stuffs in 2 grams of hydrochloric acid and 100 grams of water containing 2% of gelatine.
• Example 2 In 100 grams of water are dissolved 6 grams of gelatine, /2 gram of Nile blue sulphate, and 5 grams of N bis (-5, A, dioxypropyl)-N-allyl-sulpho-urea, 10 grams of sulphourea and 5 grams of glycerol are added.
• Example 3 A bleaching solution similar to that of Example 1 is prepared, and 15 grams of monochloracetamide and 10 grams of glycerol are added. It is applied on paper and exposed to an arc lamp.
• Example 4 In 200 grams of water are dissolved 10 grams of gelatine, 6 grams of Capri blue, 4 grams of sulphopyronine G sulphate, 8 grams of methoxyresorcin-benzeine chloride. 500 grams 01' a 20% alcoholic solution 01' diethylallyl-sulpho-urea, 100 grams of N-di-p-oxyethyl- Nallylsulpho-urea and 50 grams of N-B-oxyethyl-N'allyl-sulpho-urea and finally grams of oxamide are gradually added. 20 grams of this solution is spreadout on a square meter of baryta paper.
• Example 5 Organic photographic support paper is acidified with diluted sulphuric acid and it is coated with 20 grams of the following solution: grams of water, 10 grams of gelatine and 10 grams of propionyl-hydrazide. Then a sitized paper for photographicbleaching.
• Example 7 -30 grams oi cellulose acetate are dissolved in 200 grams of acetone. To this solution are added, 50 grams of methyl alcohol containing 0.08 gram of brilliant cresyl blue, 0.05
• Example 8--A bleaching solution is prepared with 5 grams of basic dye-stuffs and 300 grams of 2% sulphuric acid, 30 grams of thiosinamine and 50 grams of diethyanolallylsulpho-urea. Finally, 35 grams of imidazole chlorhydrate are added.
• Example 9 An aqueous solution of crystallized violet sensitised by thiosinamine is spread out on paper. A solution of diacetylimine is then applied.
• X represents an element of the oxygen series selected from a group consisting of 0, Se, Te, and R1, R2, R3 each represents a saturated monovalent element, radical or group with the exception of compounds having a sensitizing power, by choosing the organic compounds in question among the compounds belonging to the following classes: acyl amides, acyl imides, amidines, guanidines, hydrazides, hydrazidines, hy-

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Paper (AREA)
• Pyrrole Compounds (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=9313602

Family Applications (1)

Country Status (4)

Cited By (40)

• 0
  • BE BE437152D patent/BE437152A/xx unknown
• 1938
  • 1938-12-03 FR FR846996D patent/FR846996A/fr not_active Expired
• 1939
  • 1939-12-01 GB GB31297/39A patent/GB586389A/en not_active Expired
  • 1939-12-02 US US307324A patent/US2328166A/en not_active Expired - Lifetime

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