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
  • G03C5/315—Tanning development
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
  • C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
  • C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
  • C07D307/56—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
  • C07D307/70—Nitro radicals
  • C07D307/71—Nitro radicals attached in position 5
  • C07D307/72—Nitro radicals attached in position 5 with hydrocarbon radicals, substituted by nitrogen-containing radicals, attached in position 2
  • C07D307/73—Nitro radicals attached in position 5 with hydrocarbon radicals, substituted by nitrogen-containing radicals, attached in position 2 by amino or imino, or substituted amino or imino radicals
• • 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
  • G03C1/00—Photosensitive materials
  • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
  • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
  • G03C1/42—Developers or their precursors

Definitions

• aqueous photographic processing baths and the development of these layers may possibly be followed by a transfer process.
• those parts of the developer substances which have remained unused in the unexposed areas of the silver halide layers can be transferred to a second layer which contains one or more substances which react 'with the transferred developer substance to form non-laterally reversed positive images of the original.
• the unexposed parts of the silver halide layer can be transferred to a transfer material which contains substances which blacken the silver halide of the transferred parts of the silver halide ;emulsion layer.
• the colloid relief produced by the tanning heat development of the silver halide emulsion layer can be used as printing matrix.
• the silver halide layers used for carrying out the above processes contain, in addition to developer substances, substances which increase the intrinsic moisture of the layer or which split off water during the heat development, such as salts containing water of crystallization, polyhydric alcohols, oligo-saccharides or caprolactam.
• these layers are relatively unstable, especially silver halide layers which contain unhardened gelatin. After several months storage at room temperature or after 1-2 days storage at 40-60 C., these layers will only develop very slowly or incompletely so that in the case of tanning development, for example, the exposed areas are not sufficiently tanned by the heat development so that an imagewise transfer of portions of that layer is not possible.
• the main cause for this deterioration of the layers is the drying to which the layers are exposed during storage. By moistening the rear surface of the negative material, they can be restored so that they can again be developed.
• Drying of the photographic layer is due to the fact that the binding agent of the layer adsorbs water and that in. photographic materials having a paper support ICC emulsion layer into the paper support.
• part of the emulsion layer seeps down into the paper base. The layer thus becomes so firmly anchored to its foundation that the unexposed parts can no longer be transferred or can only incompletely be transferred to the transfer material by heat. By moistening the transfer material or the negaitve, the unexposed parts of the gelatin can again be transferred.
• Drying of the emulsion layer cannot be prevented by adding to the layer still more substances which increase the moisture of the layer. Layers containing too many such substances become sticky on the surface so that they become practically useless. Moreover, the photographic properties of the light-sensitive layer are impaired by the said compounds if the concentrations applied are too high.
• One object of our invention is to provide a light-sensitive photographic element, which is to be processed by a heat development and transfer process and which avoids the disadvantages referred to above.
• photosensitive materials which contain an intermediate layer between the silver halide emulsion layers containing the developer and the support are excellently suitable for. heat development and transfer processes.
• the said intermediate layers consist of water-soluble film-forming colloids containing hydroxy or carboxyl groups or mixtures of the said water-soluble film-forming colloids with water-dispersible polymers such as polyvinyl acetate.
• polyureas containing sulfo groups as described in U.S. Patent No. 2,988,538.
• the polyureas are prepared from diamines and diisocyanates;
• Alginic acids and derivatives thereof preferably alkali metal or earth alkali metal salts such as sodium alginate, potassium alkinate or calcium alginate, or esters of alginic acid in particular with alkylene glycols such as alginic acid and propylene glycol ester;
• the above film-forming agents are capable of taking up many times their own weight in water.
• silver halide emulsion layers containing developer compounds as used for heat development and heat transfer processes may be applied to the intermediate layers of the present invention.
• Suitable silver halide emulsions and transfer materials are described in the patent specifications mentioned above.
• Silver halide layers containing developer compounds are sufficiently stable when cast on the hydrophilic intermediate layers of the present invention and even after prolonged storage they develop sufliciently rapidly, so that satisfactory images, for example, relief images are obtained on the transfer material.
• the hydrophilic intermediate layers of the present invention may contain a smaller quantity of additional substance which provide a desired amount of moisture in the light-sensitive layer or the transfer layer during the heat development step. Such substances are compounds which split off water on heating or compounds which increase the residual moisture content of the layer.
• Compounds of the first mentioned type are urea, salts containing water of crystallization such as sodium citrate or preferably sodium acetate; compounds of the second mentioned type are, for example, polyhydric alcohols such as sorbitol, glycerol or polyethylene glycols.
• an original light-sensitive element containing an intermediate layer of a salt of polyurea sulfonic acid as the binding agent and oligo saccharides, such as sucrose, maltose and lactose.
• substances which act as formaldehyde binding agents such as dimedone or semica rbazide may be added to the intermediate layers, especially when they are used with tanning heat development, the addition of these substances serving to prevent hardening of the silver halide emulsion layers due to diffusion of formaldehyde from the paper support.
• the process of the present invention which is characterized by the use of photographic materials containing the intermediate layer can be advantageously used for the production of printing matrixes or stencils for screen printing.
• the exposed silver halide emulsion layer which contains a tanning developer and is applied to a suitable intermediate layer of the present invention is developed after it has been brought into contact with a suitable material for screen printing such as tissue paper or rice paper.
• tissue paper can then be separated from the negative by slight moistening with water so that the developed and tanned parts of the emulsion layer adhering to the tissue paper are torn out of the emulsion layer and transferred to the tissue paper while the untanned parts of the emulsion layer remain adhering to the intermediate layer.
• the transferred tanned parts form on the tissue paper a relief which is impervious to dyestuffs, the screen dyes then passing through the remaining parts of the tissue paper.
• the paper may be coated with the following solutions:
• the pH of the emulsion is adjusted to 5.3 with sulfuric acid.
• the emulsion is applied in known manner to the intermediate layer and dried.
• the exposed negative material is developed by heating to 120 to 200 C. preferably to 160 to 185 C. for 0.5 to 30 seconds in an apparatus normally used for heat development, e.g., by means of a high gloss press, drying drum between heated rollers or. in an apparatus as described in Belgian Patent No. 628,174.
• a negative image which is tanned in the exposed parts is obtained.
• a negative image of the same quality is still obtained if the photographic material is processed after 6 to 12 months storage.
• the developed negative may be brought into contact with a transfer material to producea non-laterally reversed copy, the unexposed anduntanned parts of the developed silver salide emulsion layer being transferred to the transfer material by heating to 120 to 200 C. preferably to 170 C. and are blackened there.
• the two papers are separated immedately after heating, a black positive image of the originalbeing obtained. on the transfer material.
• Suitable transfer materials are described in Belgian Patent No. 640,596.
• they may be produced by the following method: A non-baryta-coated paper is coated with the following solution and dried:
• the paper may be coated with the following solutions:
• a 4% aqueous solution of the sodium salt of polyurea sulfonate (prepared by polyaddition of the sodium salt of 4,4-diamino-diphenylethane-2,2-disulfonic acid with toluylene-diisocyanate) containing 20 g. of maltose, or containing 50 g. of sucrose; or
• the pH of the emulsion is adjusted to 5.0 with critic acid.
• the emulsion is applied in known manner to the intermediate layer and dried.
• the product is worked up as described inExar'nple .1 for which the following transfer material may be used. I r
• EXAMPLE 3 This example serves to explain the production of screen printing matrixes.
• the exposed silver halide emulsion layer is developed in contact with rice paper as normally used for screen printing and developed in one of the apparatus mentioned in Example 1. After development, the rice paper is slightly moistened with water or the whole paper bathedfin water. The moist rice paper is now separated from the developed silver halide emulsion layer, whereby the exposed and tanned parts of the emulsion layer are torn out and transferred onto the rice paper while the unexposed and untanned portions of the developed silver halide emulsion layer remain adhered on the intermediate layer.
• the transferred tanned portions of the emulsion layer form a relief layer impermeable to dyes on the rice paper, so that a printing matrix or stencil for screen printing has been obtained.
• the said relief layer is a nonlaterally reversed negative image of the original.
• intermediate layer indicated above under (a) the following intermediate layers are also suitable for the production of printing matrixes or stencils for screen printing:
• EXAMPLE 4 A light-sensitive material having an intermediate layer of the present invention is used for carrying out the process described in French Patent No. 1,369,253.
• the emulsion is applied in known manner to the intermediate layer and dried.
• a transfer material as disclosed in French Patent No. 1,369,253 is prepared as follows:
• This mixture is applied to a paper support and dried.
• the light-sensitive material is developed at to C. for 0.5 to 30 seconds in contact with the transfer material, using the apparatus mentioned in Example 1. After separation of the two materials, a blue image is obtained on a pale yellow background. The same result is obtained if the light-sensitive material is processed after several months storage or after two days storage at 40 C. Owing to the higher moisture content, this material develops more rapidly than the previously known materials, better whites being thereby obtained on the transfer material.
• Transfer material.70 g. of the sodium salt of polyacrylic acid and 2 g. of colloidal silicic acid are dispersed in 1 liter ofwater.
• the casting solution is cast on a sheetlike support and dried.
• the tanned portions of the silver halide emulsion layer are transferred onto the transfer layer of the above transfer material forming thereon a negative relief image of the original.
• the process of the present invention is particularly suitable for the production of printing forms for screen printing or silk screen printing as described in Example 3.
• process portions of the light-sensitive emulsion layers are transferred to a transfer sheet which is pervious to the paste of the printing dye.
• Suitable are, for example, very fine mesh fabrics such as nylon or silk fabrics or some type of paper such as tissue paper or the socalled Japanese or rice paper which is silk-like and has satisfactory mechanical properties.
• a process for producing printing forms for screen printing comprises the steps of thermally developing in contact with a screen printing sheet on'ex posed silver halide emulsion layer containing tanning developer in amount suflicient to cause the emulsion to be tanned at the exposed portions during the development, the emulsion layer being held on a support coated with an intermediate layer of a salt of polyurea sulfonic acid or 'a mixture of polyvinyl acetate and polyvinyl pyrrolidone, or salts or esters of alginic acid, or carboxyalkyl cellulose orcarboxyalkyl stanch in which the alkyl portions have up to 3 carbon atoms, moistening the screen printing sheet and separating it from the supported emulsion to cause the tanned portion of the emulsion to adhere to the sheet and come away with it while the untanned emulsion portion remains on the emulsion support.

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• Chemical & Material Sciences (AREA)
• Physics & Mathematics (AREA)
• Organic Chemistry (AREA)
• General Physics & Mathematics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Photosensitive Polymer And Photoresist Processing (AREA)
• Silver Salt Photography Or Processing Solution Therefor (AREA)
• Heat Sensitive Colour Forming Recording (AREA)
• Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)

Applications Claiming Priority (1)

Publications (1)

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Cited By (3)

Citations (4)

• 1963
  • 1963-09-30 DE DEA44169A patent/DE1189383B/de active Pending
• 1964
  • 1964-09-22 GB GB38596/64A patent/GB1067292A/en not_active Expired
  • 1964-09-22 US US398383A patent/US3301677A/en not_active Expired - Lifetime
  • 1964-09-28 BE BE653642D patent/BE653642A/xx unknown

Patent Citations (4)

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