DE2157330A1 - Photographic recording material containing at least one dye which can be faded in the presence of silver - Google Patents

Description

Photographic recording material containing at least one which can be bleached in the presence of silver dye

The invention relates to a photographic recording material with a content of at least one in the presence Dye that can be bleached from silver, consisting of a layer support, at least one light-sensitive dye applied to it Silver halide emulsion layer and, if applicable, intermediate and / or top layers »

It is known that photographic recording materials are used in the so-called silver dye fading process one or more silver halide emulsion layers are used, each of which contains a bleachable dye, the color of which is complementary to the color of that part of the Spectrum is against which the silver halide emulsion layer in question is sensitive. If such recording materials are exposed, then developed and then treated in a bleach bath, the dyes present will be proportional to that during development formed metallic silver colorless. After removal of residual silver and silver halide by silver bleaching with subsequent fixing and washing, a positive dye image is obtained in this way.

Those that can be used to carry out this silver dye bleaching process known photographic recording materials, however, have the disadvantage that their light-sensitive Dyes incorporated in layers absorb a considerable amount of the light used for exposure, so that the effective sensitivity of these photographic materials is decreased. There has therefore been no lack of attempts to eliminate this disadvantage. So it is z. B. known, the dyes by colorless dye precursor compounds, z. B. nitroso compounds or azo couplers to replace. It is also known to use special azo dyes use different colors depending on the pH of the medium exhibit. During exposure, such pH-dependent dyes have a color that is not excessive

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Light of such wavelength is absorbed to which the layer containing the dyes or layers arranged below the same are sensitive. After exposure, the pH of the recording material is adjusted accordingly in order to bring about a change in the color of the dye to the desired color. However, it is disadvantageous that the known processes indicated require an additional process step in order to convert the dyes and dye precursor compounds present in the recording materials into dyes of the desired color shade Ψ in the finished image. Another disadvantage is that the choice of dyes is limited to those types of dyes which undergo the desired color transitions.

The object of the invention is to provide a method for bleaching silver indicate certain, versatile photographic recording material which has improved through Properties in terms of photosensitivity, contrast, density and / or stability distinguishes itself for its production stable known dyes commonly used for the stated purpose can be used and for its work-up no additional procedural steps beyond the usual hatred required are.

The invention is based on the surprising finding that the specified object is thereby achieved in a particularly advantageous manner it can be solved that the dyes which can be bleached in the presence of silver are separate from the actual light-sensitive ones Layer adjacent to a precisely defined type are incorporated, which showed that recording materials of the specified type are particularly advantageously suitable for color photography or hadiography.

The invention relates to a photographic recording material containing at least one in the presence

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Dye that can be bleached from silver, consisting of a layer support, at least one light-sensitive dye applied to it Silver halide emulsion layer, and optionally intermediate and / or top layers, which is characterized by at least one silver halide emulsion layer containing the dye which can be faded in the presence of developed silver With a content of fogged silver halide grains, which form the latent image predominantly in the grain interior, as well as at least one emulsion layer which is arranged closely adjacent thereto and contains non-fogged, the latent Image predominantly on the grain surface forming silver iodohalide grains.

In photographic recording materials according to the invention, which is intended for exposure from the emulsion side the fogged emulsion layer is between the support and the unveiled silver iodohalide emulsion layer arranged. In photographic recording materials according to the invention which are used for photographic exposure are determined through the transparent support is the unveiled silver iodohalide emulsion layer arranged between the support and the veiled emulsion layer.

Photographic recording materials according to the invention, which are intended for color photography, have a support and at least three pairs of fogged and unveiled emulsion layers of the specified type. According to a In an advantageous embodiment, such recording materials have the following on top of one another in the order given arranged layers on: (1) an emulsion layer applied to the substrate made of fogged, the Silver halide grains which form a latent image predominantly in the interior of the grain and contain a cyan dye which can be faded in the presence of developed silver, (2) a red-sensitive emulsion layer made of unveiled, the Ia-

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tente image predominantly on the grain surface forming silver iodohalide grains, (3) an emulsion layer of fogged, latent image forming predominantly in the grain interior Silver halide grains, containing one in the presence of developed silver bleachable purple dye, (4) a green-sensitive emulsion layer of unshifted, the latent image predominantly on the grain surface forming silver iodohalide grains, (5) an emulsion layer of fogged, latent image forming predominantly in the grain interior Silver halide grains, containing one in the presence yellow dye that can be bleached from developed silver, and "(6) a blue-sensitive emulsion layer made of unveiled $, silver iodohalide grains forming the latent image predominantly on the grain surface.

In such multilayer recording materials It is often advantageous to apply development antifoggants to the fogged grains, which form the latent image predominantly in the interior of the grain to protect from the mercaptotype and the migration of iodide ions between layers by arrangement control of barrier interlayers.

The specified sequence of the layers proves to be particularly advantageous for those color photographic recording materials which are intended for photographic exposure from the layer side. Of course, as already mentioned, the relative position of the veiled and unshifted layers within each pair of layers can also be reversed, and the order of the arrangement of the dye-containing and light-sensitive layers can be different from that indicated, e.g. As such that the layer is arranged biaueapfindliche the substrate closest to, if the relevant color photographic recording material intended for exposure by the substrate therethrough.

According to a further advantageous embodiment, which is

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The photographic recording material is particularly advantageously used in eadiography according to the invention of a layer support which is obscured on each side with an emulsion layer of the The latent image is mainly provided in the interior of the grain forming silver halide grains, with each of these layers an emulsion layer of unveiled, the latent image is applied predominantly to the grain surface forming silver iodohalide grains, and furthermore each of the two The emulsion layers closest to the support contain a dye or a mixture of dyes which can be faded in the presence of developed silver.

Without adhering to a specific theoretical explanation of the self To want to bind playing mechanisms, it is to be assumed that the surprisingly advantageous achievable according to the invention Results can be explained, at least in part, by the fact that the emulsion containing the grains of the grain surface latent image type resulted in a product or products being developed which migrate to some of the pre-abrased grains of the inner grain latent image type located in the adjacent emulsion layer and there the inner haze centers expose so that the development of these grains, the formation of silver and the subsequent bleaching of the associated Dyes is made possible. Such effects occur in surface sensitive silver iodohalide emulsions, e.g. B. in common silver bromoiodide emulsions. Presumably it is in the important product formed in the development of such emulsions, which is part of the emulsion layer from Inner grain type migrates to the iodide ion.

The grain surface latent image emulsions useful in the photographic recording materials of the invention have a comparatively high degree of surface sensitivity and a comparatively low sensitivity to inner grains, whereas the inner grains which can be used according to the invention

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latent image emulsions have a high degree of internal grain sensitivity, but only have a comparatively low surface sensitivity. The grain surface latent image emulsions contain silver halide grains which have substantial surface sensitivity and have latent images on the surface Grain surface form when exposed to light.

The commonly known photographic silver halides are used to prepare such grain surface latent image emulsions usable e.g. B. silver bromoqodide, silver chloroiodide and | Silver chlorobromoiodide, whereby the use of silver halides, the halide component of which consists of bromoiodide has proven particularly advantageous. Typical suitable such Emulsions which form the latent image predominantly on the surface of the silver halide grains are e.g. B. from Trivelli and Smith in "The Photographic Journal" Volume 80, July 1940, pages 285 "to 288.

Typical suitable grain surface latent image emulsions are those which, when measuring the sensitivity by customary known photographic test methods, are in the form of a film sample, that is, when a portion of the emulsion to be tested is applied to a transparent support, the film sample obtained has a certain value between 0.01 and exposed for 1 second to a light intensity scale and developed for 6 minutes at 20 ° C. in a developer, hereinafter referred to as A, of the composition given below, have a sensitivity measured at a density of 0.1 above fog, which is greater than the sensitivity of a completely same sample of the same emulsion exposed in the form of a film sample in the same manner, for 5 minutes at 18, 3 bleached ° C in an aqueous 0.3 #igen potassium ferricyanide solution and 5 minutes at 18, 3 ⁰ O in a developer designated below with B of the composition given below ung is developed.

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Developer A is the usual type of Surface image developer and Developer B is an internal grain image developer with high silver halide solvent activity.

The internal grain sensitivity of the grain surface latent image emule ions can vary widely. So can such Grain surface latent image emulsions have a comparatively low internal grain sensitivity, or they can have a fairly high degree of internal grain sensitivity, but preferably internal grain sensitivity is not greater than the grain surface sensitivity. The grain surface latent image emulsions can be both high and high also have a low contrast, since advantageous results can be achieved with both types of emulsion.

The grain surface latent image emulsions can also be used in the Way to be defined as having a Dmax in excess of about 0.50 if they are applied to a layer support in such a way that about 5 »8 g of silver per m of support surface are omitted, and the film sample obtained is exposed to a step wedge and for 12 minutes in a developer designated below as C and having the composition given below is being developed. Particularly advantageous results are achieved with the aid of grain surface flat surface silver iodohalide emulsions, for example silver bromoiodide emulsions of the type indicated may contain iodide in a wide variety of concentrations, but are particularly advantageous Results obtained with such grain surface latent image iodohalide emulsions, the iodide content of which is about 0.5 to 99 mol% is, as z. As described in U.S. Patent 2,996,382.

The specified, for testing grain surface latent image and Developers which can be used for internal grain latent image emulsions can e.g. B. have the following composition:

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Developer A: g N-methyl-p-aminophenol sulfate 0.31 Sodium sulfite, anhydrous 39 »6 Hydroquinone 6.0 Sodium carbonate, anhydrous 18.7 Potassium bromide 0.86 Citric acid 0.68

Potassium metabisulphite 1.5 Make up to 1 liter with water

Developer Bt N-methyl-p-aminophenol sulfate 2.0 Sodium sulfite, anhydrous 90.0 Hydroquinone 8.0 Sodium carbonate, monohydrate 52.5 Potassium bromide 5.0

Sodium thiosulphate 10.0 Make up to 1 liter with water

Developer Ci N-methyl-p-aminophenol sulfate 2.5 Sodium sulfite, anhydrous 30.0 Hydroquinone 2.5 Sodium metaborate 10.0

Potassium bromide 0.5 Made up to 1 liter with water

The internal grain latent image silver halide emulsions which can be used for the production of the photographic recording materials according to the invention contain silver halide grains which form the latent image predominantly inside the grains. To the

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For the preparation of such silver halide grains, various conventionally known photographic silver halides can be used, e.g. B. silver bromide, silver chloroiodide, Silver chlorobromoiodide, silver chlorobromide and silver chloride. Typical suitable emulsions which form the latent image predominantly in the interior of the silver halide grains are e.g. B. in U.S. Patents 2,592,250, 2,996,382, and 3,178 described.

Typical internal grain latent image emulsions are those which are used in the determination of the sensitivity by customary known photographic methods in a non-fogged state, ie when a portion of the emulsion to be tested is applied to a transparent substrate and the film sample obtained is for a specific time between 0.01 and 1 second exposed to a light intensity scale, then ^{bleached for 5 minutes at 18.3 0} O in a 0.3% strength potassium ferricyanide solution and then developed for about 5 minutes at 18.3 ⁰ O in a developer labeled B of the specified composition, one at a Have a density of 0.1 measured above the haze, which is much higher, e.g. B. is at least 1.4 logE greater than the sensitivity of an identical Frobeanteila, which was exposed in the form of a film sample in the specified manner and developed for 6 minutes at 20 ⁰ O in a designated A developer of the specified composition.

The internal grain latent image emulsions must be partially or completely obscured before use. The concealment should be strong enough to give a density of at least 0.50 when 1 mole (AgX) of the fogged emulsion is in the

Mixture with 3 moles of grain surface latent image emulsion in a total amount of about 5.8 g of silver per m of support area

mg / square foot) is applied to a layer support and Is developed for 5 minutes in a designated B developer of the composition given. The Dmax value of the

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Unobstructed interior grain latent image emulsions should be under 0.30 when the emulsions are exposed to Dmax and 8 minutes in a developer labeled C of the specified Composition to be developed.

The obfuscation of the internal grain latent image emulsions can be used in be effected in various ways, e.g. B. in such a way that the emulsions light, X-rays or chemical fogging agents be exposed. Emulsions with high internal haze but low surface sensitivity are produced) adjustable by obscuring an emulsion that has both inner grain and grain surface sensitivity and then Bleaching of the surface image with a solution of potassium ferricyanide.

It has proven advantageous for the production of photographic Recording materials according to the invention, internal grain image emulsions to use those with development antifoggants, e.g. B. Kercaptoanti fogging agents, for example i-phenyl-5-mercaptotetrazole and chemically related compounds of the type described in U.S. Patent 3,397,987.

* The molar ratio of the silver content of the grain surface latent image emulsion layer to the veiled inner grain latent image emulsion layer can be very different and depends on various factors, e.g. B. the type of emulsions used, the contrast of the same and the desired color st off density. So z. B. molar ratios, based on the silver content, of grain surface formation emulsion to veiled inner grain formation emulsion of 4-2: 1 to 1:10 or even over a wider range than the specified range have been shown to be feasible, but the specified ratio is particularly advantageous Range from about 5 * 1 to 1: 5.

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Those in the photographic recording materials according to Emulsion combinations that can be used in the invention can be developed in developers using silver halide solvents, z. B. potassium thiocyanate (KSON) or sodium sulfite, contain, as well as in developers that have little or no silver halide solvent activity. on in all cases should the silver halide solvent effect The developer used should not be too high, otherwise the iodide-containing grain surface latent image emulsion would result in iodide would be released indiscriminately and the obscured internal grain latent image emulsion would become spontaneously developable, which is a general Dye bleaching would result. Opposite is in the developer an appropriate amount of silver halide solvent, e.g. B. on a water-soluble thiocyanate thiosulfate or sodium sulfite, it occurs in the veiled grain emulsion a development only in those Be - = - areas in which the exposed surface-sensitive grains are developed so that those achievable according to the invention Advantages are the result.

Without wanting to be bound by a specific theoretical explanation, the likely effect of the in the developer present silver halide solvent and iodide ion (In this context, reference is made to Examples 12 and 15 given below) will. The effect of these components that can be used as additives can be explained with regard to the limit iodide concentration, which is necessary for the development of the pre-fogged internal grain latent image emulsion. Obviously must a minimum or limit concentration of iodide, d. H. a certain concentration threshold, to be reached before the pre-veiled inner grain latent image grains are developable. The iodide ion concentration in the area of these grains can be just below this limit to prevent the development, and the development of the latent Veil centers only take place when this threshold increases.

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is exceeded at least to a small extent.

To improve the sensitivity of photographic recording materials according to the invention it therefore proves to be advantageous to use an iodide ion concentration ensure that in the entire internal grain pattern emulsion is slightly below the specified limit value. Then hike the iodide ions released from the developed exposed areas of the surface-sensitive emulsion layer to the adjacent grain pattern emulsion, only a low concentration of migrating iodide ions is required, to exceed the specified threshold and the development of the pre-veiled internal grain latent image emulsion to be effected in the form of an image pattern which corresponds to the exposure of the surface-sensitive emulsion layer generated image.

The concentration of iodide ions below the threshold can be effected in a number of ways. So z. B. the developer used contain iodide ions in an amount which is below that which represents the limit concentration for the inner grain image emulsion. Furthermore, a present in the developer solution silver halide solvent may Open w due to its solvent effect the transition of silver iodide from the jodidhaltigen surface-sensitive emulsion layer to the corresponding areas of the inner grain latent image Emuleion effect, but the concentration of silver halide solvent again must not be so high that the silver halide in such Amount is dissolved that the iodide limit concentration in the corresponding areas of the internal grain latent image emulsion layer is exceeded.

The specified solvents can also cause the grains of the internal grain image emulsion layer to dissolve and develop of the inner grain pattern, especially if this Grains not by antifoggants, as they are e.g. B. in the

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U.S. Patent 3,397,987 are protected. Therefore, when such antifoggants are not present in the internal grain latent image emulsion layer, the content should be Silver halide solvent in the developer used must be correspondingly low.

Another way of controlling the iodide content is to adjust the photographic recording material itself to incorporate a source of iodide ions. This can e.g. B. be done by incorporating an inorganic iodide, e.g. B. of lead iodide, thallium (I) iodide or silver iodide, or by Incorporation of an organic iodine complex in a separate layer of the recording material.

The limit values to be aimed for for the iodide concentration in the developer or in a layer of the photographic recording material as well as the optimal limit values for the concentration of silver halide solvent can be determined by routine tests. So z. B. a number of test strips of photographic recording materials, which differ only in the iodide content, exposed and developed in an analogous manner, whereupon the maximum iodide content can be determined for an image with the desired contrast. Similarly, identical film samples can be developed with a number of developer solutions which have different iodide and / or silver halide solvent contents, whereupon the values required to achieve optimal results are determined. The specified methods for increasing the iodide content a by adding iodide or silver halide solution to the developer solution or by incorporating a special iodide-releasing layer into the photographic recording material have proven to be particularly advantageous when the silver iodohalide emulsion materials in question are thin , as is the case with e.g. . B. is the case in multilayer color photographic recording materials, or if the re-usable

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te silver iodohalide has a low iodide content. If the emulsion layers in question are comparatively thick and if the iodide content of the silver iodohalide present is comparatively high, then it is in the Hegelian sense no benefits of providing additional iodide.

To prevent development fog that can form when the iodide content of the developer is excessive increases sharply, which z. B. usually occurs when the developer solution is used for a long time without being refilled "it has proven to be advantageous to provide the photographic recording materials according to the invention with an anti-fog layer, as is the case, for example, in French patent specification 2,006,427. This is a low-sensitivity emulsion layer with a low iodide content, e.g. B. a silver chlorobromide emulsion layer below the pre-veiled Inner grain latent image Eaulsiönssehicht or can be arranged above the surface-active emulsion layer.

The invention is illustrated in more detail by the accompanying drawing, in which!

Fig. 1 is an enlarged cross-section of a monochrome photographic material according to the invention in the scheme during different exposure and processing stages,

Pig. FIG. 2 shows an enlarged cross section through a multilayered color photographic recording material according to FIG Invention in Scheaa in various exposure and Processing stages, and

'ig- 3 an enlarged cross-section through a photographic. Recording material according to the invention in the scheme intended for use in the Radiograph! «.

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In step I of Fig. 1, the exposure of a photographic recording material according to the invention 10, which for black and white or monochrome photography is intended, shown which consists of a layer support 11 on which a veiled internal grain latent image emulsion layer 12 is applied. This emulsion layer 12 contains a dye of any color which, under the conditions of the Silver dye bleaching process is bleachable, or they contains a mixture of bleachable dyes which are advantageously capable of producing a neutral image. In the immediate vicinity of the emulsion layer 12, namely, over the layer 12, in the form of an adjacent layer, is an unveiled, surface-sensitive silver bromoiodide emulsion layer 13 applied. Furthermore, further layers not shown in FIG. 1 can be conventionally known ! Type, e.g. B. an antihalation layer on the Layer support 11, an adhesion-improving base layer between the support 11 and the emulsion layer 12, or a gelatin top layer acting as a protective layer of the emulsion layer 13

After the exposure shown in step I, the photographic Recording material 10 developed, e.g. B. in a conventional known black and white developer solution. The result this black and white development is shown in stage II of FIG. 1 in the diagram. In the illustration they are comparative large developed silver iodohalide grains 14 of the emulsion layer 13 can be seen, from which the released iodide ions in the manner indicated by the arrows 15 in the Proximity of the pre-veiled, comparatively fine-grained inner grain latent image silver halide grains the layer 12 migrate. In the layer 12, the iodide ions obviously act in the Way that they expose the inner veil centers and allow these grains to develop in a very effective manner. In the emulsion layer 12, close to these developed grains, there is a silver developed in the presence of

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Fade-out dye arranged, or optionally a mixture of such dyes, for. B. a mixture that becomes a- ' a neutral picture. Since the dye or dyes are close to the reduced silver of the inner grain image emulsion layer are arranged and because the reduced silver because of the small grain size of the emulsion and the high degree of Pre-exposure is in a finely divided state, the dye bleaching effect is greatly improved and the Development speed increased.

| In stage III of FIG. 1, the recording material 10 is after shown after bleaching and fixing. Sas bleaching can be done with the help of a commonly known silver dye bleach and fixing by means of a conventionally known fixing agent, e.g. B. a thiosulfate solution. Like in the As can be seen in the drawing, the area 13 'is the entire area of the emulsion layer 13 and the exposed area of the Emulsion layer 12 comprises, now clear. The silver halide present in these areas is due to the fixing agent has been removed and the dye and metallic silver in the exposed area of the emulsion layer 12 are bleached been. In the unexposed area 12 'of the emulsion layer On the other hand, the dyes remain.

The embodiment shown in FIG. 1 is a comparatively simple form of photography Recording material according to the invention, and further advantageous embodiments are shown in Figures 2 and 3, namely a multilayer recording material intended for color photography in FIG. 2 and a recording material intended for hadiography in FIG. 3 <

In Fig. 2 there is shown a multilayer photographic recording material according to the invention, which is intended for 'subtractive three-color photography. In stage I.

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the pig. 2 becomes the exposure of a recording material 20 shown, which consists of a substrate 21, for. B. a cellulose acetate support, on which a Layer 22 of a veiled internal grain image sirber halide emulsion, in which a cyan dye which can be faded in the presence of developed silver is dispersed is. On the layer 22 is a layer 23 of a unveiled grain surface image silver iodohalide emulsion applied, which sensitizes to red light with the aid of a suitable spectral sensitizing dye is.

In multilayer color photographic recording materials of the type shown, the migration of the iodide ion and bleach catalyst advantageously controlled to prevent development in a pair of emulsion layers adversely affects the grains of the adjacent pair of emulsion layers. So are z. B. the red sensitive Emulsion layer and the associated layer containing dye and obscured internal grain image grains from the green-sensitive layer and the associated layer with a Content of dye and inner grains separated by a barrier layer 24, which allows a diffusion of iodide ions and reduced bleach catalyst. A typical suitable layer of this type is e.g. B. an insensitive one fine-grain emulsion layer, e.g. B. a layer of a Lippmann emulsion, which advantageously also has one may contain diffusion-inhibiting compound, e.g. B. a ballast group containing p-quinone, for example 2,5-di-n-octyl-pbenzoquinone, or other compounds of this type, as e.g. B. in British Patent 1,159,690 and U.S. Patent 3 457 074.

Furthermore, such barrier layers can also contain filter materials, z. B. filter dyes or colloidal silver to the exposure of the red and green sensitive layers

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to prevent blue light and the color separation of the photographic System to improve.

The layer 24 shown in FIG. 2 is around a barrier of the specified type. Thus, the layer 24 contains an insensitive Lippmann emulsion that the Migration of iodide ions between layers 23 and 25 controls or inhibits.

On top of the barrier layer 24 is a veiled internal grain latent image emulsion layer 25 applied, which is a purple dye and on this layer is a green light sensitized grain surface image silver iodohalide lulaion layer 26 applied. Above that there is another barrier layer 27 »over this one veiled one Internal grain image encapsulation shows 28 with a content of a yellow dye, and over there is a blue sensitive grain surface image silver iodochalide emulsion layer 29 applied.

For the sake of simplicity, various customary known, optionally usable layers have been omitted from this illustration. z. B. Atrial protection layers and top layers.

Step II of Fig. 2 shows the photographic material after black and white development, the arrows showing the migration of iodide ions from the exposed areas of the surface sensitive emulsion layers 29, 26 and 23 in the adjacent veiled internal grain image layers indicate where these ions form the pre-veiled fine grain internal grain latent image silver halide grains expose in the form of an image pattern that corresponds to the exposure and development of the corresponds to the image pattern formed immediately above the surface-sensitive emulsion layer. A hike on this iodide ion is prevented by the barrier layers 24 and 27.

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-19- £ 157330

After the black and white development shown in stage II of FIG of the exposed recording material, that present in the individual emulsion layers becomes non-reduced Silver halide made soluble in a conventional known fixer and then washed out from the Recording material removed. The recording material obtained is then placed in a dye bleach bath in which those in emulsion layers 22, 25 and 28 are present Dyes in the areas corresponding to the developed silver images are destroyed. Eventually that will The recording material obtained is silver-bleached, fixed and washed to remove any remaining silver and silver salt to remove.

The recording material thus obtained after bleaching and fixing is shown in step III of FIG. As can be seen, layers 28 ', 25' and 22 · positive yellow, purple and blue-green images, respectively, so that in this way a positive three-color reproduction of the original is obtained.

The illustrated in Fig. 3 photographic recording material according to the invention 35 is, as already mentioned, for Intended for use in radiography. It consists of a substrate 36, which is coated on both sides with emulsion layers 37 "and 38. The layers 37 and 38 act they are veiled internal grain latent image emulsion layers that contain a bleachable dye or, more advantageously Way, contain a mixture of such dyes that lead to a neutral image. Adjacent to the layers 37 and 38 are those from grain surface image silver iodohalide emulsions existing layers 39 and 40 are applied.

The indicated radiographic or X-ray film 35 can be exposed directly to X-rays or gamma rays, or it can be used in in the usual known manner in combination with one or more

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Ren fluorescence intensifying screens can be used. In any case, this recording material is X-rays or Gamma rays exposed, whereupon it evolves and then practically in the same way as this related with the photographic material shown in Fig. 1, a dye bleach and a Is subjected to silver bleaching treatment.

If the photographic recording materials according to the invention are used for radiographic purposes, then

fc the very high opacity that can be achieved with their help, of particular advantage. Both proves to be beneficial in the Badiographle as well as for other purposes z. B. also the quick and easy au accomplishing development and work-up, as well as the stability of the usable Dyes. Another advantage is that development and work-up can be simplified by ehotography of the wet positive dye image with a negative microfilm. This combination of a layer of unveiled Grain surface latent image silver iodohalide emulsion and a Layer of fogged internal grain latent image silver halide emulsion with dye content can also be used to blur Masking can be used or in combination with others

Layers to achieve special effects. So z. B. a positive dye image on one side of the support and to mask one on the other side negative image can be used.

As also shown in the examples below, there is the silver dye bleaching process comprising the following process steps: (1) Development of the exposed silver halide under alkaline conditions, (2) oxidation of a silver metal image in an acidic medium with the aid of an organic one Oxidizing agent which acts as an electron carrier, (3) Diffusion of the reduced form of the electron carrier from the silver surface due to the structure of the violin, and (4) irreversible

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JAHK »ir; O? A * 5

Reduction of the pale arenic dye, in Hegel one Azo dye, in a colorless form, with associated Oxidation of the electron carrier, which can return to the silver surface and carry out further reactions, and the therefore it is often called a "catalyst".

As already mentioned, the development of the exposed silver halide is a customary black and white development in alkaline solutions of developer compounds, e.g. B. of hydroquinones, catechins, aminophenols, 3-fyrazolidones, ascorbic acid and its derivatives, reductones or phenylenediamines. For the development of silver iodide emulsions which can be used according to the invention as unsolarized silver iodohalide emulsions, the use of pyrogallol and chemically related developer compounds, such as those described, for. B. by James et al in "Phot. Sei. Eng." Volume 5 * Fr. 1, (1961), pages 21 to 29, have proven to be particularly advantageous. The developer solution used may also contain auxiliary developer compounds, e.g. B. 3-pyrazolidone compounds, for example i-phenyl-3-pyrazolidone, and also, as already mentioned, iodide compounds and / or silver halide solvents. Furthermore, the developer compounds or developer precursor compounds can be incorporated into one or more layers of the photographic recording material. Their activation takes place in the usual known manner, for. B. by treatment with an alkaline solution.

A wide variety of conventional, known compounds of this type can be used as silver dye bleach catalysts which oxidize the silver metal image and serve as electron carriers for the reduction of the bleachable dye. Typical suitable compounds of this type are t. B. Chinoxalines and phenazine as i. As described in U.S. Patent No. 2,270,118 . Further suitable catalysts are, for example, in the USA patent steps * 2 183 395 * 669 517, 2 627 461 «

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BATH ORIGINAL

2 578 710, 2 541 884, 2 410 025, 2 348 894, 2 341 034 and 2,270,118 and British Patent 533,190.

Various types of dyes can be used in the photographic recording materials of the invention. As a rule, all dyes and mordants are suitable which can be used in conventionally known silver dye bleach materials, e.g. Such as those described in U.S. Patents 3,414,411 and 3,498,787 and the references mentioned therein, as well as the neutral dye mixtures of the type described in British patent specification 999,996.

When the recording materials are used in a system with internal camera development, the developer is placed in a conventionally known container with an alkaline one Activator, 8th B. in the manner described in U.S. Patent 3,414,411. The acid, the bleach components and that Fixing agents are incorporated into the paper sheet, which is generally used as the image receiving layer in the solvent transfer process. If necessary, a Timing layer can be applied on top of this paper sheet forming the image receiving material in order to prevent premature release of the bleaching and fixing components. The contents of the container are drawn over the surface of the exposed film distributed in the usual known manner; after After a suitable period of time, the components present in the paper sheet are then released, so that a stable, positive dye image is formed. The image obtained can be viewed through the support when the sheet of paper is permanently applied in the form of a layer on top of the film.

The photograph! See photographic materials used after the Erfinuad Alt place of their creation

209826/0834 BAD ORfGWAL

Emulsions can also contain a wide variety of known additives customarily used for such purposes. Typical suitable additives of this type which can be used in a particularly advantageous manner are, for. B. optical sensitizers, chemical sensitizers, sensitizers, hardeners, plasticizers, antifoggants, Stabilizers, antistatic agents, surface active agents and matting agents,

In the layers, e.g. B. photographic emulsion layers, the recording materials according to the invention, the most varied of customary known colloids, both alone and in combination with one another, as carriers and binders. Typical suitable hydrophilic binders are e.g. 3. both naturally occurring substances, "for example, proteins such. As gelatin, gelatin derivatives, cellulose derivatives, polysaccharides, for example dextran and gum arabic _r and synthetic polymeric substances, for. Example, water-soluble polyvinyl nnectivity, for example polyvinylpyrrolidone, and acrylamide polymers.

The photographic emulsion layers and layers of other types of recording materials according to the invention can furthermore, alone or in combination with hydrophilic, water-permeable colloids, synthetic polymeric compounds other type included, e.g. B. dispersed vinyl compounds, for example in latex form, and especially those which the dimensional stability of the photographic. Increase recording materials. Typical suitable synthetic polymers are z. B. in U.S. Patents 3,14-2,568, 3,193,386, 3,062,674, 3,220,844, 3,287,289 and 3,411,911. as The use of water-insoluble polymers of alkyl acrylates and methacrylates has proven particularly advantageous, Acrylic acid and sulfoalkyl acrylates or methacrylates, as well of polymers with hardening facilitating, for training

209826/0894

groups capable of cross-linking and of polymers with repeating sulfobetaines in the Canadian Patent 774 054 has been shown to be of the type described.

The photographic recording materials according to the invention can have a wide variety of conventionally known layer supports. Typical suitable supports are e.g. B. films made of resinous materials, made of glass, paper or metal. In general, flexible substrate to be used in a particularly advantageous manner, substrate made of paper, which may be partially acetylated or coated with baryta and / or an "olefin polymer _t particularly a polymer of an ct-olefin having 2 to 10 carbon atoms, for example with Polyethylene, polypropylene, or ethylene butene copolymers.

According to the different layers of the recording materials light absorbing agents and filter dyes may be incorporated into the invention, including the photographic layers be e.g. Those described in U.S. Patents 3,253,921, 2,274,782, 2,527,583, and 2,956,879 Type. Optionally, the dyes used can be stained, as z. Described in U.S. Patent 3,282,699 will.

The sensitizing dyes and others the photographic Additives to be incorporated into recording materials according to the invention can be in the form of aqueous solutions or suitable organic solutions are used. The additives can be incorporated in a conventional manner, e.g. B. after the in U.S. Patents 2,912,343, 3,342,605, 2,996,287, and 3,425,835.

For the production of the photographic recording materials According to the invention, the photographic layers can have

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the substrate can be applied by a wide variety of customary known coating processes, e.g. B. by immersion inspection, Air knife coating, drop curtain coating or extrusion coating using hoppers, how this z. As described in U.S. Patent 2,681,294. Optionally, two or more layers can be used at the same time be applied, e.g. As described in US Pat. No. 2,761,781 and British Pat. No. 837 095 " procedure. Furthermore, the silver halide layers can be evaporated in a vacuum, as is done, for example, in US Pat. In British Patent 968,453 and U.S. Patent 3,219 4-51 is described.

The following examples are intended to explain the invention in more detail.

For the preparation of the recording materials used in these examples the specified layers were made of polyethylene terephthalate films Existing support is applied, which is provided on the back with a black dye layer was. Examples 7 to 9 illustrate the process, whereas Examples 1 to 6 and 10 are comparative examples acts.

The recording materials described in Examples 1 to 9 contain, in addition to the specified dye, a dye stain, namely copolyfc. -Methallyl-N-guenidylketimin-styrene) glycölsäuresalζ.

The following dyes were used to carry out the procedures described in the examples:

as a yellow dye, so-called ⁿ Solantine yellow 5435 "(traded by

from Allied Chemical Corp.), identical to "Solantine-Gelb RL", color index No. 29 025,

as Purpurfarbitoff eog "Solantine-Böia 4 BL" (gthaadelt von

of Allied Chemical Corp "), - * · * - Color-Index No. 25380, and.

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BADORfQtNAL

as blue-green dye 8-acetajaido-2 / ~ 4- (8-amino-1-hydroxy-3,6-

disulfo-2-naphthoazo) -2,5-methoxyphenylazo_7-1-naphthol-3 »6-disulfonic acid, Tetrasodium salt.

Example 1 (comparison example)

In this example, as in Examples 2 and 3, conventionally known photographic recording materials are used Silver dye fading type described in which the | applied azo dye to the photosensitive silver halide emulsion layer is incorporated.

On a support of the specified type, a layer of a non-displaced, coarse-grained, highly sensitive, surface sensitive gelatin silver bromoiodide emulsion, the containing a yellow azo dye. The coating was carried out in such a way that 1.16 g of silver (108 mg / sq.ft.), 0.75 g of yellow azo dye (70 mg / sq.ft.) and 5 * 86 g gelatin (546 mg / sq.ft.) were omitted.

Example 2 (comparative example)

P As in Example 1, one containing a purple azo dye was used Silver bromoiodide emulsion in the manner on a layer

2
applied to the carrier, that per m of carrier surface 1.16 g of silver (108 mg / eq.ft.), 0.56 g of purple azo dye (52 mg / sq.ft.) and 5 * 34- S gelatin (4-96 mg / sq.ft.) were omitted.

Example 3 (comparative example)

As in Beiapiel 1 is a cyan azo dye ent retaining Silberbromojodidemilaion to a layer support in The white "ufgetragen that per» carrier surface ² 1.16 g of silver (108 »g aq.ft /.) 0.75 6" cyan azo dye and 6.14 g of gelatin (5? 1 eg / eq.ft.) Were omitted.

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BATH ORIGINAL

-27- 2,57330

Example 4 (comparative example)

In this example, as in Examples 5 ″ and 6 photographic recording materials described in which the photosensitive emulsion layer over one of the azo dye containing gelatin layer is arranged.

A yellow azo dye was placed on a support containing gelatin layer applied in such a way that per m support area 0.75 g azo dye (70 mg / sq.ft.) and 3.23 g Gelatin (300 mg / sq.ft.) Was omitted, and the silver bromo-3odide emulsion described in Example 1 became the gelatin layer obtained applied in such a way that 1.16 g of silver (108 mg / sq.ft.) and 2.65 g of gela'tine (246 mg / sq.ft.) accounted for.

Example 5 (comparison example)

A gelatin layer containing a purple azo dye was applied to a support in such a manner that per The support area accounted for 0.56 g of purple azo dye (52 mg / sq.ft.) and 2.69 g of gelatin (250 mg / sq.ft.) and the obtained one Gelatin layer was that described in Example 1

2 silver bromoiodide emulsion applied in such a way that per m Support area accounted for 1.16 g silver (108 mg / sq.ft.) And 2.65 g gelatin (246 mg / sq.ft.).

Example 6 (comparative example)

A blue-green azo dye was applied to a support containing gelatin layer applied in such a way, p

that per m of support area 0.75 g of blue-green azo dye and. 3.48 g of gelatin (324 mg / eq.ft.) Were accounted for, and on the one obtained The silver bromoiodide emulsion described in Example 1 became the gelatin layer applied in such a way that per m carrier

209826/0894

area 1.16 g silver (108 mg / sq.ft.) and 2.65 6 gelatin (246 mg / sq.ft.) Accounted for.

Example 7

This example and Examples 8 and 9 are photographic Recording materials according to the invention described, the one applied to a support layer of a veiled internal grain latent image emulsion containing an azo dye, as well as a layer applied to this layer of an unveiled grain surface sensitive "Have silver bromoiodide emulsion.

A layer of a pre-processed layer was applied to a layer support. ski wobbled, a yellow azo dye containing inner latent image-grain silver chlorobromide emulsion applied in such a way that per m ² of support surface 0.43 g of silver (40 mg / sq.ft.), 3.70 g gelatin (344 mg / sq.ft.), and 0 , 75 g of yellow azo dye (70 mg / sq.ft.) Were used, and a layer of the specified non-fogged silver bromoiodide emulsion was applied to the resulting layer in such a way that 1.16 g of silver (108 mg / sq.ft .) and 2.65 g gelatin (246 mg / sq.ft.) were omitted.

Example 8

A layer of a pre-veiled, an internal grain latent image silver chlorobromide emulsion containing purple azo dye applied in such a way that per m of support surface 0.43 g of silver (40 mg / sq.ft.), 3.16 g of gelatin (294 mg / sq.ft.) And 0.56 g of azo purple dye (52 mg / sq.ft.) Were accounted for, and on the resulting layer became a layer of the indicated silver bromoiodide emulsion as described in Example 7 applied.

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Example 9

A layer of a pre-veiled, an internal grain image silver chlorobromide emulsion containing cyan azo dye applied in such a way that per m of support surface 0.43 g of silver (40 mg / sq.ft.), 3.96 g gelatin (368 mg / sq.ft.) And 0.75 g blue-green azo dye (70 mg / sq.ft.) Was omitted and the layer obtained was a layer of the indicated silver bromoiodide emulsion as described in Example 7 applied.

Example 10 (comparative example)

In this example, a photographic material which contains two emulsion layers but no dye.

A layer of a pre-fogged one was applied to a layer support Indoor grain latent image silver chlorobromide emulsion in

ρ
the manner applied in that per m support surface 1.77 g of silver (164.5 mg / sq.ft.) and 1.95 g of gelatin (181.5 mg / sq.ft.) accounted for, was obtained in the obtained layer is a layer from a silver bromoiodide emulsion, as described in Example 1, applied in such a way that 4.85 δ of silver (450 mg / sq.ft.) and 11 g of gelatin (1025 mg / sq.ft.) were accounted for per m of support area, and on the layer obtained was finally a gelatin

P layer applied in such a way that 0.89 g per m of support surface

Gelatin (82.5 mg / sq.ft.) Was omitted.
Example 11

This example describes the exposure, development and testing of the photographic recording materials explained in Examples 1 to 10.

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-30- 2167330

The film samples were passed through a neutral density wedge for 1/25 seconds using an Eastman Ib sensitometer exposed to a tungsten light source with filtering through a so-called "Kodak Wratten filter Fr. 47B". The exposed film samples were used for 5 minutes at 23.9 ° C in a developer designated below as D of the following Composition developed.

Developer D:

2.5 δ 30.0 S. 2.5 S. 10.0 ε 0.5 S. 2.0 S. o, O5g 1 liter

N-methyl-p-aminophenol sulfate Sodium sulfite, anhydrous Hydroquinone Sodium metaborate Potassium bromide

Potassium thiocyanate (as silver halide

solvent)

5-methylbenzotriazole made up with water

The developed dye-containing film samples (Examples 1 to 9) were rinsed in water for 10 seconds, then fixed for 3 minutes at 20 ^° C. in a fixing bath of the following composition containing a hardener:

Sodium thiosulfate 240.0 g

Sodium sulfite, anhydrous 15.0 g

Acetic acid, 28 % 48.0 ml

Boric acid, crystals 7.5 g

Potassium alum 15.0 g

filled up with Waeier to 1 liter

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-31- 2T57330

and then at 32.2 ° C in one of the following with a dye calibration solution A bleached dye bleaching solution s

Dye bleach solution at

Thiourea 100 g

37.5% hydrochloric acid 200 ml acetic acid 15 ml

2-Hydroxy-3-aminophenazine 150 mg made up to 1 liter with water

The following bleaching times were observed for the dye-containing film samples corresponding to Examples 1 to 9:

Examples 1, 4 and 7 'x 50 seconds

Examples 2, 5 and 8ί 40 seconds and

Examples 3, 6 and 3 °. 120 seconds.

2-Hydroxy-3-aminophenazine was used to prepare dye bleach solution A dissolved in a mixture of the specified amount of acetic acid and 15 ml of water and the resulting solution added to the solution obtained from thiourea and hydrochloric acid.

The film sample containing no dye (Example 10) was rinsed with water and fixed. All film samples were in Following the specified treatment, rinsed with water and dried in air. The images obtained were sensitometric tested. The densities were measured using a "Macbeth Quantalog" densitometer, model TD-102. For determination For the densities of the yellow, purple and blue-green dyes, so-called "Class A58 blue, green and red filters" were used .

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The results obtained are shown in Table I below.

Table I.

Film rehearsal
according to
Ex. D min

Sensitivity at 0.1 above Dmin

Sensitivity at 0.1 below Dmax (color)

y Value Dmax

10

0.15

100

1.9

3.3

1 0.22 4th 0.94 7th 0.18 2 0.22 5 1.32 8th 0.18 3 0.13 6th 1.52 9 0.50

43 155

57 145

23 58 85

0.04 0.27 0.14 1.15 0.55 0.64 0.54 1.29 0.22 .1.66 0.44 0.52 0.92 1.40 0.31 2.10 0.59 1.35

The results obtained show that the photographic materials according to the invention (Examples 7, 8 and 9) have a higher sensitivity than known recording materials, in which the dye is incorporated in the light-sensitive emulsion layer (Examples 1, 2 and 3), and they also show that the photographic recording materials according to the invention lead to a higher contrast than recording materials in which the dye is below the light-sensitive emulsion layer arranged gelatin

209826/0894

ink layer is incorporated (see. Examples 4, 5 and 6). Example 12

This example is exposure, development and testing further film samples of the photographic recording materials described in Examples 1 to 10 are described, but with a developer other than that for development developer used to carry out the procedure described in Example 11 was employed.

Film samples of the recording materials described in Examples 1 to 10 were 1/25 seconds through a Fleutral density step wedge with the help of a so-called "Eastman 1B" sensitometer of a tungsten light source with filtering Using a so-called "Kodak Wratten filter No. 4-7B" exposed. the exposed film samples were further treated as follows:

Development in Developer E, the one below

indicated composition 2 1/2 Hin., 32.2 ⁰ yy

Wash in water 30 sec., 20 ⁰ g Fixing in a fixing solution of the in Example 11 given composition 3 Hin., 20 ⁰ C Wash in water Bleach in dye bleach solution A for 40 to 120 seconds

as stated above (see example 11)

Wash in water Drying in liuf t

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The developer E used had the following composition on:

Developer Ex

i-hienyl-3-pyrazolidone (so-called "phenidone") 1 G Hydroquinone 20th G Sodium sulfite, anhydrous 50 G Sodium metaborate, 8HoO 22nd S. Potassium bromide 15th G Potassium iodide O , 04 g topped up with water 1 liter

pH 9.6 at 21.1 ⁰ C

The images obtained were tested sensitometrically. the Density determinations were made in the manner indicated. The results obtained are shown in Table II below.

Table II

Film sensitivity sensitivity

_fc according to 0.1 at 0.1

E.g. Dmin above Dmin below Dmax (color) value Dmax

10 0.17 87 - 1.45 2.85

1 0.22 16.5 0.26 0.80 4th 0.99 62 0.22 1.25 7th 0.20 105 0.65 1.02 2 0.21 31 0.69 1.38 5 1.38 58 0.26 1.76 β 0.17 229 1.01 0.96 3 0.10 18th 1.22 1.80 β 1.51 58 0.42 2.04 9 0.39 96 0.85 1.72 209826/0894

The results obtained show that the developer E used was because of its comparatively poor silver halide solvent power to an advantageous improvement in the maximum density and contrast of the dye images obtained without increasing the minimum density.

In further experiments it was found that if the iodide ions are omitted from developer E, the sensitivity and the Contrast fell significantly and the minimum density of the dye image was increased. The additional use of iodide ions in the developer solution thus proved to be advantageous since the silver iodohalide content of the top applied Layer was comparatively low in the two-layer films tested. In further experiments it was shown that when the the amount applied or the iodide content of the photosensitive emulsion layer that is used by the addition of iodide Advantages achievable by developers are less pronounced. On the other hand, it turned out to be an additional benefit of using of iodide ions in the developer consists in increasing the stability of the process, which can be explained by that in the development of the silver iodobromide emulsion layer Iodide ions are released, which get into the developer, which leads to impairment of the sensitometric properties of the developed recording materials, and that when using substantial amounts of iodide ions in the developer the effect of released iodide is suppressed to a minimum, so that reliable results with regard to sensitometric Properties were obtained.

Example 15

This example also shows the influence of a silver halide solvent present in the black and white developing solution.

209826/0894

Sample strips of a recording material according to the invention of the type described in Example 8 were exposed sensitometrically through a test object with graduated density and under Use of black and white developer solutions of the composition given below with different levels of Silver Halide Solvent (KSCIT) developed.

The photographic recording material used consisted of a support on which a layer of a pre-fogged, fine-grained internal grain latent image silver chlorobromide emulsion was applied of the type described in U.S. Patent 2,996,382 containing a purple azo dye and mordants for this azo dye applied in the manner

was that per m of support surface silver chlorobromide in an amount corresponding to 0.43 g of silver (40 mg / sq.ft.), 3.16 g of gelatin (294 mg / sq.ft.), 0.56 g purple azo dye (known under the name "Solantine-ßosa 4BL"), as well as 1.69 g Copoly- (cc -Methallyl-N-guanidyl-ketimin-StyTol) glycolic acid salt as Mordants for the purple azo dye were omitted. On top of this layer was a layer of a non-fogged surface-sensitive Silver bromoiodide emulsion in the manner

brought that per m of support area silver bromoiodide in one Amount corresponding to 1.16 g silver (108 mg / sq.ft.) And 2.65 g gelatin (246 mg / sq.ft.) Were omitted.

The exposed film samples were treated as follows:

Black and white development * 2 min.

To wash . 30 sec.

Fixing ** 3 min.

Wash 5 min.

Silver dye bleach *** 2 min.

Wash ... 1 min.

Cupri bleach **** 2 min.

Fixing **. 2 min.

Wash 5 min.

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* in developer of the following composition:

N-methyl-p-aminophenol sulfate 3.0 g

Sodium sulfite, anhydrous 45.0 g

Hydroquinone 12.0 g

Sodium carbonate, monohydrate 80.0 g, potassium bromide 2.0 g

made up to 1 liter with water

+ KSCN as silver halide solvent in the concentrations given in Tab. III

** in fixing solution of the composition given in Example 11

♦ ** in a silver dye bleach bath of the following composition:

HCl 100 ml

Fhenazine (bleach catalyst) 0.018 g

Thiourea 100 g

made up to 1 liter with water

in Cupr bleach bath of the following composition:

CuSO ^ 100 g

HCl 37% 15.0 ml

made up to 1 liter with water

The results of the densitometrisohen tests carried out are listed in Table III below.

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1.76 0.32 1.76 0.04 1.70 0.04 1.04 0.04

Table III

κ KSCN / 1 developer Dmax Itain

0 1 2 4

The results show that the image reproduction is improved if a certain amount is in the developing solution, but not there is too much silver halide solvent.

Correspondingly beneficial results, i. H. qualitatively improved Yellow dye images were obtained using photographic recording materials of the specified type, as the dye under the name "Solantine-Gelb RL" known yellow azo dye (C.I.No. 29025).

Examples 14 and 15

In these examples, other photographic images of the present invention are used Described recording materials which have barrier layers arranged between two pairs of emulsion layers.

Recording materials were produced which had the following basic layer arrangement. The following Numbers given in brackets on the components listed for the individual layers denote the respective concentrations in g / m.

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Layer 5

Layer 4

Layer 5

Layer 2

Layer 1

Blue-sensitive gelatin silver bromoiodide emulsion containing 6 mol% silver iodide (1.16), gelatin (2.65)

Veiled internal grain image gelatin silver bromide emulsion (0.43), gelatin (3.70), yellow Azo dye (0.75)

Very fine-grain silver bromide emulsion of the Lippmann type (0), gelatin (2.15), 2,5-di-n-octyl-p-benzoquinone (0.15)

Green sensitive gelatin silver bromide emulsion containing 6 mol% silver iodide (1.40), gelatin (3.18)

Veiled internal grain image gelatin silver bromide emulsion (0.52), gelatin (3 »25), purple azo dye (0.56)

Gelatin (2.15) polyethylene terephthalate support

Layers 1 and 4 also included that in the preceding Examples of dye mordants.

The layer arrangement of those used in Examples 14 and 15 Recording materials was, with reference to the given basic layer arrangement, as follows:

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Example 14:

The recording material had the stated basic layer arrangement, d. H. in layer 3 there was no Lippmann emulsion.

Example 15 * The recording material had the same layer arrangement, with the exception that in layer 3 there were 1.08 g of Lippmann-type emulsion ^{per m 2 of support surface.}

4 film samples each of those described in Examples 14 and 15 multilayer recording materials were measured by a graduated density test object using a so-called "Wratten filters No. 98" exposed to blue light and then developed and further treated at 23.9 C as follows:

Development (a) washing fixing (b) P washing

Dye bleaching (c)

To wash

Cupri bleach (d)

Fix (b)

To wash

dry

6 min.

30 sec.

3 min.

3 min.

4, 8, 10 or 15 min.

1 min. 8 min.

2 min. 5 min.

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(a) in a black and white developer of that given in Example 13 Composition, but instead of KSCN, 0.1 g of 5-methylbenzotriazole per liter of solution as an anti-fogging agent contained.

(b) in a fixing solution of the composition given in Example 11

(c) in a silver dye bleach solution of that in Example 13 specified composition

(d) in a Cupri bleach bath as given in Example 13 Composition.

The images obtained were tested. The results obtained showed that in the recording material used in Example 15 effective bleaching of the yellow dye image in layer 4 occurred, but even after 15 minutes of treatment in the dye bleach bath only little or at all no bleaching of the magenta dye image in layer 1 occurred. In contrast, the recording material used in Example 14 showed which had no intermediate layer containing a Lippmann emulsion, a noticeable loss of density in Layer 1 at the time of complete bleaching of Layer 4.

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Claims (2)

Claims 1. Photographic recording material containing at least one dye which can be bleached in the presence of silver, consisting of a substrate, at least one light-sensitive silver halide emulsion layer applied thereon, and optionally intermediate and / or top layers, characterized by at least one in the presence Containing dye that can be bleached from developed silver ™ silver halide emulsion layer containing fogged, silver halide grains which form the latent image predominantly in the grain interior, as well as at least one Emulsion layer arranged closely adjacent to this and containing non-fogging, predominantly the latent image silver iodohalide grains forming on the grain surface 2. Photographic recording material according to claim 1, characterized in that the fogged internal grain latent image emulsion layer contains a development fog inhibitor. t 3 photographic recording material according to claim 2, characterized in that the development fog inhibitor consists of a mercapto antifoggant. 4. Photographic recording material according to Claims 1 to 3 »characterized in that the veiled emulsion layer an internal grain latent image gelatin chlorobromide emulsion contains and between the support and an adjacent unveiled emulsion layer, the one Gelatin silver bromoiodide emulsion containing, is arranged. 209826/0894 Photograpb.iscb.es recording material according to claims 1 to 3 »characterized in that there are at least three pairs of the specified veiled and unveiled Contains emulsion layers arranged on the support in the following order: (1) one fogged emulsion layer with internal grain latent image silver halide grains and a blue-green dye that can be faded in the presence of silver, (2) a non-fogged, emulsion layer sensitized to red light with grain surface latent image silver iodohalide grains, (3) a fogged emulsion layer having internal latent image silver halide grains and one in the presence purple dye that can be bleached from developed silver, (4 ·) an unmistakable, opposite green light sensitized emulsion layer with grain surface latent image silver iodo halide grains, (5) a fogged emulsion layer containing internal latent image silver halide grains and a yellow dye which can be faded in the presence of developed silver, and (6) an unveiled, opposite blue light sensitive emulsion layer with grain surface latent image silver iodohalide grains. 6. Photographisch.es recording material according to claim 5 * characterized in that between each unshifted Silver iodohalide emulsion layer and the layer thereover When the emulsion layer is obscured, a barrier layer which inhibits the migration of iodide ions is arranged. 7. Photographic recording material according to claim 6, characterized in that the barrier layers have an insensitive, contain fine grain silver halide emulsion. 8. Photographic recording material according to claims 6 and 7 »characterized in that each barrier layer is a 209826/0894 a ballast group-containing p-quinone as a diffusion-inhibiting agent and at least those above the green-sensitized Emulsion layer arranged barrier layer contains a blue light filtering substance. 9. Photographic recording material according to claim 1 for Use in radiography, characterized in that a silver halide emulsion layer on each side of the support with veiled inner grain latent image silver halide grains and a dye which can be faded in the presence of developed silver each of these layers has an unveiled grain surface latent image-silverj applied odohalide emulsion layer is. 10. Photographic recording material according to claim 9, characterized characterized in that the veiled internal grain latent image emulsion layers are a mixture of in the presence of developed silver which can be bleached out and which are capable of forming a neutral image. 2 09826/0894 VS Blank page