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
  • G03C8/00—Diffusion transfer processes or agents therefor; Photosensitive materials for such processes
  • G03C8/24—Photosensitive materials characterised by the image-receiving section
  • G03C8/26—Image-receiving layers
  • G03C8/28—Image-receiving layers containing development nuclei or compounds forming such nuclei

Definitions

• the invention relates to a silver salt diffusion transfer method making use of a negative material, having a silver halide emulsion layer on which an image is formed by exposure, and a receiving material, to which the image is transferred, wherein the exposed negative material is moistened with a liquid effecting the development and is subjected to compression together with the moistened receiving material, which is made of paper, felt or textile material.
• German patent specification No. 764,572 the socalled silver salt diffusion method is described and it is stated that various substances are used as the receiving material, e.g. uncoated papers, textile sheets, wood, Celluloid and other plastics materials and the like.
• the term material the invention refers to any sheet-form material.
• the transfer can be aided by the presence of substances favoring diffusion.
• the diffusing or diffused silver halide can be developed imagewise without exposure, whereby this development is aided by added nuclei or reactants.
• the developed image is transferred to a baryta paper or to a textile underlayer or support, which has been moistened in the same bath as the silver halide material.
• a separate positive or receiving layer has sometimes been provded in which the reduction nuclei are arranged. This layer is usually arranged on a special support so that the layer and support form the receiving material.
• this receiving layer can be used independently of a support and, by way of example, can be applied as a cover layer on the negative layer.
• a colloidal cover and receiving layer Such an embodiment is described in German patent specification 1,171,740 and referred to as a colloidal cover and receiving layer. No reduction nuclei need be contained in this layer.
• reduction nuclei are supplied to the colloidal receiving layer by means of the processing liquid.
• known reduction nuclei are sulphides, selenides, polysulphides, polyselenides, thiourea, mercaptans, stanno halides, heavy metals or their salts, as well as fogged silver halides and sulphides of heavy metals such as antimony, bismuth, cadmium, cobalt, lead, nickel and silver.
• the heavy metals for example, silver, gold, platinum, palladium and mercury, especially in colloidal form, are considered the most effective.
• the noble metals are particularly preferred.
• the image-receiving layer is thus provided as a cover layer on the negative, and a sheet of material is provided for receiving the image developed in the cover layer. Since according to patent specification 764,572 the diflicultly soluble silver compound or colloidal silver, which is produced in the receiving layer, is nondiffusable, the colloidal cover or image-receiving layer containing the developed image is also transferred during the transfer to the receiving sheet, paper or the like.
• German patent specifications 764,572 and 1,171,740 are based on the use of reduction nuclei, such as have been used in the silver salt diffusion method generally known as the Copyrapid method.
• the reduction nuclei according to patent specification 1,171,740 are provided in the processing liquid, which not only serves for carrying out the developing, but also for the complex salt formation of the unexposed and undeveloped silver halide, then the same limitations exist, in respect to the stability of such solutions, as are known to exist in developers used in the silver salt diffusion method. These limitations are due to the simultaneous presence of air oxidation products, used and unused developing substances, the rising content of silver halide solvents caused by the increased number of copies and silver halide complex compounds which diffuse into the solution and may be active as reduction nuclei.
• the basic task of the invention is to find a method by which the production of a positive image on an uncoated support or layer is made technically possible by the silver salt diffusion method, while at the same time the liquids used superior stability and make possible a very large number of prints without replacement or replenishment.
• the expression uncoated paper designates a support containing no film-forming colloids, but for which only a wetting with an aqueous solution is provided.
• the invention at the same time aims to use simple and cheap materials, one of which is used uncoated, and which especially do not involve the problem of a plurality of coatings on a support. This is so because with a plurality of coatings, there is the possibility that, during long storage times and/or through varying influence of atmospheric moisture and temperature, an impairment of the layers can result if special binders are not provided.
• the receiving material of the nature described is moistened before being combined or compressed with the negative transfer material, with a liquid that is different from the one for negative development, and containing in aqueous solution reduction nuclei or substances forming reduction nuclei and a silver salt solvent as well as a wetting agent.
• the invention has the advantages that no film-forming colloid-receiving layer is used and that ordinary diffusion negative materials as available on the market can be used, whereby the processing liquids can be employed according to their composition in such a way that excellent stability is effected while at the same time a large number of prints can be produced.
• a further important advantage of the invention is that with the use of customary industrial diffusion negative materials, for example of the Copyrapid dry negative type, prints of superior quality are produced although uncoated receiving material is used.
• Copyrapid is a trade name of Agfa-Gevaert A. G. Therefore, no expensive specially prepared papers have to be used.
• moistening is not understood to designate coating, but a wetting with an aqueous solution of the reactants which have no layer-forming character. According to the invention, it is sufficient, for example, to wet one side of the receiving support. With coatings, it is customary to dry these. According to the method of the invention, which uses a receiving material that, for example, comprises paper, the term moistening essentially means that this receiving material is treated in the moist state, to wit, after it has been moistened with the aqueous solution of the reactants.
• German patent specification 1,168,927 in which ordinary paper used as a receiving material is coated before the transfer process.
• the paper is coated with a solid layer which is not influenced by diffusion or transfer, but which assumes a definite color at a stated temperature.
• moistening it is possible to moisten only one side of the receiving sheet, to wit, that side on which the image is to be formed.
• the moistening can thus be carried out by any known method, such as spraying, application with. a moistening roller or the like.
• the receiving material is pressed through the aqueous nuclei containing solution in a known way.
• a significant feature is that, as the processing liquid for the receiving material, a solution with a concentration of only approximately 0.02% of a hexachloroplatinic-(IV) acid and/or a gold (III) chloride hydrochloride is employed. It has been shown that, apparently for the reasons given above, in using such a liquid, far more prints can be produced than if the nuclei themselves are contained in the developing liquid.
• the present invention is distinguished not only in that processing baths are simple, stable and relatively cheap, but in developing for the first time an industrially workable method in which ordinary papers can be used as receiving sheets, without having to provide additional coatings for the negative material. In the latter case, the advantage-of the use of a simple sheet of paper as the receiving material would be practically negated by complication of the neagtive.
• an apparatus with two liquid baths may be used.
• the transfer material and the receiving material are conveyed through the respective bath before they are carried to a pair of ordinary compression rollers.
• the invention creates a two-bath-method with the use of a receiving material which remains uncoated and is only moistened separately and is supplied to the compression rollers in the moist state, while an ordinary negative is used as the negative material.
• This provides for the first time a practical solution for producing high quality prints with the silver salt diffusion method on a receiving material made of ordinary paper, film or textile.
• Mirasol is a trade name for a wetting agent, manufactured by Tetenal Fototechnik, Hamburg, Germany and is available on the market.
• a silver salt diffusion transfer method in which an image is formed by exposure on a silver halide emulsion layer of a negative material, and the exposed layer of the negative material is moistened with a liquid for effecting development of the image which is transferred to a receiving material by pressing together the layer of the negative material and the receiving material, the improvement which comprises that the receiving material is an uncoated sheet which, immediately prior to contact with the layer of the negative material, is moistened with a liquid containing in aqueous solution hexachloroplatinic (IV) acid and/or gold (III) chloride hydrochloride and silver salt solvent.
• the receiving material is an uncoated sheet which, immediately prior to contact with the layer of the negative material, is moistened with a liquid containing in aqueous solution hexachloroplatinic (IV) acid and/or gold (III) chloride hydrochloride and silver salt solvent.
• the liquid for moistening the receiving material comprises a solution containing about 0.02% of a hexachloroplatinic (IV) acid and/or of a gold (III) chloride hydrochloride.
• a liquid of diiferent composition than said developer liquid comprising an aqueous solution containing (a) a silver salt solvent

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Color Printing (AREA)
• Photosensitive Polymer And Photoresist Processing (AREA)
• Coloring (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=7274527

Family Applications (1)

Country Status (8)

Cited By (2)

Citations (3)

• 1965
  • 1965-11-17 DE DE19651572110 patent/DE1572110A1/de active Pending
• 1966
  • 1966-10-17 CH CH1494466A patent/CH477021A/de not_active IP Right Cessation
  • 1966-10-20 GB GB47096/66A patent/GB1161331A/en not_active Expired
  • 1966-10-27 AT AT1000566A patent/AT269645B/de active
  • 1966-11-08 FR FR82887A patent/FR1504081A/fr not_active Expired
  • 1966-11-14 BE BE689662D patent/BE689662A/xx unknown
  • 1966-11-15 US US594383A patent/US3510301A/en not_active Expired - Lifetime
  • 1966-11-16 NL NL6616137A patent/NL6616137A/xx unknown

Patent Citations (3)

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