DE3144021A1 - Process for producing colour equidensites - Google Patents

Abstract

Colour equidensites are produced by the dye diffusion process, using a recording material with a negative silver halide emulsion layer and a combination, associated therewith, of a reducible dye release agent and an ED compound of low reactivity ( tau 1/2 values between 1.1 and 20 s). An alkaline developer preparation is used for development in the presence of a developer combination consisting of A) a 1-phenyl-3-pyrazolidone derivative and B) a compound of the formula I <IMAGE> in which X and Y are -OH or <IMAGE> Q is a radical for completing a benzene ring, n is 0 or 1, R<1> and R<2> are hydrogen, alkyl or aryl, R<3> and R<4> are hydrogen or alkyl or both together are a radical to complete a cyclic amino group.

Description

Process for the production of color equidensites

The invention relates to a method for photographic production of color equidensites with the help of the color diffusion transfer method.

Photographic processes for the production of aquidensites are known. This is understood to mean photographic imaging processes in which image areas a template that has a density within a limited density interval, can be selectively mapped. The production of black and white #quidensites is carried out in GB 654 931 described. The recording material used there contains two on top of each other layered emulsion layers, wherein according to example 2 the lower layer germs for physical development. The production of the Aquidensite takes place through chemical development of the exposed part of the emulsion (negative) and physical Development of the unexposed part of the emulsion (positive) The upper emulsion layer is then removed and a black and white equidensite appears in the lower emulsion layer obtained in the form of a borderline between negative and positive. According to example 1 of the aforementioned British patent, the lower emulsion layer does not contain any Development seeds; the equidistant site is obtained through a series of operations; consisting of first exposure (pictorial), initial development, reverse exposure (evenly), second development and removal of the upper emulsion layer, after DE-AS 1 597 509 are black and white equidensites through a combination of a silver chloride emulsion and a silver bromide emulsion prepared by the bromine ion diffusion method. Colored equidensites can also be produced by chromogenic development, if the recording material or the developer contains suitable color couplers. Likewise by chromogenic development, according to US Pat. No. 4,131,464, color equidensites are used of a complex multilayer recording material and by a multi-stage development process generated.

The procedures described are cumbersome and because of the partial numerous processing steps time-consuming.

As far as colored equidensites are produced using the known method processing necessarily includes besides chromogenic development further steps to remove silver or silver halide (bleach-fix).

The invention is based on the object of a simplified method for the production of color equidensites, for which the recording material used contains only one light-sensitive silver halide emulsion per color and that only comprises a processing step (development).

The invention relates to a process for the photographic production of color equidensites, characterized in that a color photographic recording material with a photosensitive element arranged on a layer support, the at least one negative silver halide emulsion layer and a combination of a reducible color splitter and an ED compound with a contains half-life t1 / 2 of 1a6 to 20 s determined by the method given in the description, exposed imagewise and in the presence of a developer combination consisting of A) a 1-phenyl-3-pyrazolidone derivative and BB a compound of the following general formula I in which mean Q a radical to complete a benzene ring optionally containing further substituents n 0 or 1 R1 R2 hydrogen, alkyl or aryl 3 R4 hydrogen, alkyl or both together a radical to complete a cyclic amino group, e.g. B.

Pyrrolidino, developed with an alkaline developer preparation is, and that in the development in an image-wise distribution from the dye releaser released diffusible dye by diffusion transfer into a through transferring diffusible anionic dyes, dyeable image-receiving layer will.

For the implementation of the method according to the invention are accordingly of essential importance: 1.) the light-sensitive arranged on a layer support Element; 2.) the image-receiving layer which can be dyed by diffusible anionic dyes, the integral part of the color photographic recording material rials, d. H. together with the photosensitive element on the same support can be arranged or arranged on a separate layer support can be; 3.) the special developer combination of components A and B, these can be contained individually or together in the alkaline developer preparation be or in one or more layers of the color photographic recording material.

As a support for the color photographic used according to the invention Recording material can be those customarily used in photographic practice transparent and non-transparent carrier materials use One the, z. B. Films made of cellulose esters, polyethylene tere phthalate, polycarbonate or others film-forming polymers as well as glass or paper.

The photosensitive element of the color photographic used in the present invention Recording material contains for the production of monochrome equidensitivity images a negative working photosensitive silver halide emulsion layer; and this associated combination of a color releaser and one defined below ED connection. This combination can be in one to the silver halide emulsion layer adjacent layer or in the silver halide emulsion layer itself. For the representation of several equidensites, i. H. Production of multicolored equidistant images the light-sensitive element can assign several such assignments gene of dye releaser, ED compound and light-sensitive silver halide emulsion layer included, the different silver halide emulsion layers being different Color releasers associated with spectral sensitivity usually dyes of different types Deliver color.

There are many possible combinations here. It can be, for example combine several layers, each with a negative-positive gradation, or Layers with a negative-positive gradation with layers that only have a positive gradation exhibit. Furthermore, the sensitometric distance between negative and positive gradation can be designed variably (width of the equidensite).

Different spectrally between the different assignments sensitized silver halide emulsion layer and dye releasers can become alkali-permeable Separating layers are located, which essentially have the function of a color falsification to prevent. Such release liners are particularly effective when they make connections contain, the diffusing developer oxidation products to render harmless capital. In the method according to the invention, however, there is such a presence Separation layers are not essential as the carry over colors are only functional Have character, but do not serve to reproduce colors true to color.

Under "assignment" and "assigned" is understood that the mutual Arrangement of silver halide emulsion layer, ED connection and dye releasers are of such a nature that interaction between them is possible is a pictorial correspondence between developed silver and consumption to the ED connection on the one hand as well as between the ED connection that is not used and dye releasers on the other hand, so that in accordance with the undeveloped Silver halide creates an imagewise distribution of diffusible dye will.

This requires light-sensitive silver halide and a combination from color releasing agent and ED compound not necessarily in the same layer exist; they can also be placed in adjacent layers, which each belong to the same shift unit.

To ensure sufficient interaction between the color splitter and To ensure the associated ED connection, we recommend that you use these two To accommodate compounds of a combination in the same layer, however need not be identical to the associated silver halide emulsion layer.

The reducible dye releasers used in combination with the ED compounds and in each case in association with a silver halide emulsion are non-diffusing coloring compounds which release a diffusible dye under alkaline development conditions by reduction or as a result of a reduction. Reducible paint releasers are described in DE-OS 2 809 716, DE-OS 30 08 588, DE-OS 30 14 669, EP-A 0004 399, and GB-A 80 12 242. Reducible paint releasers used particularly preferably according to the invention correspond to the following formula II: in which R1 is alkyl or aryl; R2 is alkyl, aryl or a group which, together with R3, completes a fused ring; R³ is hydrogen, alkyl, aryl, hydroxyl, halogen such as chlorine or bromine, amino, alkylamino, dialkylamino including cyclic amino groups (such as piperidino, morpholino), acylamino, alkylthio, alkoxy, aroxy, sulfo, or a group which fused together with R one Ring completes; R4 alkyl; R5 is alkyl or preferably hydrogen; A is the remainder of a diffusible dye or dye precursor; X is a bivalent link of the formula -R- (L) (R) ~, in which R is an alkylene radical with 1-6 carbon atoms or an optionally substituted arylene or aralkylene radical and the two radicals R have the same meaning or different from one another Can have meanings; L -O-, -CO-, -CONR6-, -SO2NR6-, -0-CO-NR6-, -S-, -SO- or -S02- (R6 = hydrogen or alkyl); p 0 or 1; q 0 or 1; m 0 or 1, and where at least one of the radicals R v R ~ R3 R4 contains a ballast radical.

The alkyl radicals represented in formula II by R¹, R, R³ and R5 can be straight-chain or branched and usually contain up to 18 carbon atoms. Examples are methyl, n-propyl, tert-butyl, tetradecyl, octadecyl. The through the mentioned radicals R1, R2 and R3 represented aryl radicals are, for example, phenyl groups, which can be substituted, e.g. B. by long-chain alkoxy groups.

In an acylamino radical represented by R³, the acyl group derives from aliphatic or aromatic carboxylic or sulfonic acids. With the through R2 and R3 completed fused rings are given to before carbocyclic rings, e.g. fused-on benzene or bicyclo [2,2,1] heptene rings.

An alkyl radical represented by R4 can be straight-chain or branched, be substituted or unsubstituted and contain up to 21 carbon atoms. Examples are methyl, nitromethyl, phenylmethyl (benzyl), heptyl, tridecyl, pentadecyl, heptadecyl, -C21H43.

Preferred embodiments of the dye releasers used according to the invention are those in which R1, R2 and R3 are not together in a quinoid carrier radical contain more than 8, in particular not more than 5, carbon atoms, and R4 is an alkyl radical represents with at least 11 carbon atoms.

Preferred embodiments are also those in which R1 is a Alkoxyphenyl radical with at least 12 carbon atoms in the alkoxy group and R2, R3, R4 together do not contain more than 8 carbon atoms.

The reducible dye releasers used with preference contain, per dye residue A, a releasable quinoid carrier residue of the formula which makes it diffusion-proof LCarquin11 in which R1, R2, R3, R4, R5 have the meanings already given.

As dye residues are basically the residues of dyes of all Dye classes suitable, as far as they are sufficient are diffusible, to pass through the layers of the photosensitive material into the image-receiving layer to be able to diffuse. For this purpose, the dye residues with one or several alkali-dissolving groups. As an alkali-solubilizing agent Suitable groups include carboxyl groups, sulfo groups, sulfonamide groups as well as aromatic hydroxyl groups. Such alkali-solubilizing groups can be used in the dye releasers used according to the invention be pre-formed or only from the splitting off of the dye residue from the carrier residue that is contaminated with ballast groups result. Of dyes which are particularly suitable for the process according to the invention are to be mentioned: azo dyes, azomethine dyes, anthraquinone dyes, Phthalocyanine dyes, indigoid dyes, triphenylmethane dyes, one last those dyes that are complexed or complexable with metal ions.

Among the residues of dye precursors are the residues of such compounds to understand that in the course of photographic processing by usual or additional Processing steps, be it through oxidation, be it through coupling, through complex formation or by exposing an auxochrome group in a chromophoric system, for example by saponification, can be converted into dyes. Dye precursors in this Sense can be leuco dyes, couplers or also dyes that in the course of the Processing can be converted into other dyes.

Unless there is a distinction between dye residues and the Residues of dye precursors are essential, the latter should im following also under the Understood the designation of dye residues will.

Remnants of ballast are those that make it possible to the dye releasers or other additives in the commonly used photographic materials used to store hydrophilic colloids in a diffusion-proof manner. For this purpose are preferred Organic radicals suitable, the generally straight-chain or branched aliphatic Groups with generally 8 to 22 carbon atoms and optionally also carbocyclic ones or contain heterocyclic aromatic groups. With the rest of the molecule are these residues either directly or indirectly, e.g. B. through one of the following groups linked: -NHCO-, -NHSO2-, -NR-, where R is hydrogen or alkyl, -0- or -S-. In addition, the ballast residue can also contain water-solubilizing groups, such as B. sulfo groups or carboxyl groups, which in certain cases are also anionic Form. Because the diffusion properties depend on the molecular size of the used Depending on the overall connection, it is sufficient in certain cases, e.g. B. if that used Whole molecule is large enough, or if the dye releasers using so-called oil-forming or high-boiling coupler solvents in emulsified form in the layers are incorporated, as ballast residues also shorter-chain residues, z. B. Isoamyi- or tert-butyl radicals to be used.

The photosensitive element further contains one or more of the ED compounds already mentioned, each in association with a silver halide emulsion layer and a paint releaser. These are reducing agents that are under the conditions of the alkaline development image-wise through exposed Silver halide or oxidized by oxidation products of auxiliary developer compounds and under the same conditions, on the other hand, the reducible dye releasers able to reduce. The ED connections are also intended to be used during processing their assignment to a specific silver halide emulsion layer and the assigned Retain color releasers and therefore have only a limited, if at all Agility on; they are preferably in a diffusion-proof form in the respective Layers stored The ED connections are, for example non-diffusing derivatives of hydroquinone, p-aminophenol, benzisoxazolone or Åscorbic acid (e.g. Bo ascorbyl palmitate).

For the method of the invention ~ the ED compounds must have an in have a certain way dimensioned reactivity. This can be through the Half-life measured in seconds ') 1,' 1 # 2 of the discoloration of oxidized 1Sp-tolyl-4 -methyl-4-hydroxymethyl-3-pyrazolidone (HTP) by reacting with the test substance Characterize ED connection. The oxidized phenidone derivative is colored and goes on reduction into colorless products. By photometric measurement at 513 nm can be the change in concentration of the oxidized phenidone derivative and thus determine the reactivity of the ED compound. ED compounds which can be used according to the invention have a reactivity under the conditions of those described below Test method corresponds to a half-life t1 # 2 of 1.6 to 20 s. The half-life is determined as follows.

Solution I (0.8 mmol HTP in 1000 ml methanol / water in a volume ratio 1/9) is mixed with solution II (0.4 mmol K3Fe (CN) 6 in 1000 ml 2N NaOH). HTP is converted into a colored oxidation product.

Solution III containing 0.1 mmol of the is then added to this mixture ED compound to be tested in 1000 ml of methanol or water. Oxidized HTP is reduced in the process. This process is photometric by measuring at 513 run tracked. The half-life r can then be calculated from the decay curve that is obtained Determine 1/2.

The lower the value found, the higher the reactivity the ED connection.

The Durrum blulti-mixing system was used to carry out the experiments, Model D-133 from Durrum Instrument Corporation, California, USA.

It turns out to be beneficial if the ED connections are not but are used in disguised form as so-called ED precursor compounds, which are not reducing agents themselves, but under the conditions of development convert into the actual ED compounds, for example by hydrolysis.

To the extent that such ED precursor compounds are used, their reactivity is not only driven by the reducing power of the ED compound, but their speed of formation is also of decisive importance. Useful ED compounds are mentioned above all in DE-OS 30 06 268.

These are in particular hydroquinone lactones of the following general formula III wherein: Rl is a carbocyclic or heterocyclic aromatic ring; R2, R3 R4 identical or different substituents, namely hydrogen, alkyl, alkenyl, aryl, alkoxy, alkylthio, amino or 3 4 R3 and R together complete an anchored, in particular carbocyclic, ring.

An aromatic ring represented by R in formula III may be carbocyclic ring, e.g. B. a phenyl v naphthyl or anthracenyl group, or a 5- or 6-membered heterocyclic ring with at least one of Re teroatome N, O, S as a ring member, e.g. an imidazolyl, thienyl, oxazolyl, pyrrole or pyridyl group. The carbocyclic and heterocyclic aromatic rings can be unsubstituted or mono- or polysubstituted as well as condensed contain carbocyclic or heterocyclic rings, which in this case are not aromatic need to be.

As a substituent on the aromatic ring represented by R1 and, if applicable, on rings fused to them, for example: Halogen such as fluorine, chlorine, bromine or iodine, hydroxy, sulfo, sulfamyl, trifluoromethylsulfonyl, Amino, nitro, cyano, carboxy, carbamoyl, alkoxycarbonyl, alkyl, alkenyl, cycoalkyl, especially cyclohexyl or cyclopentyl, aryl, especially phenyl, or heterocyclic Groups, the latter groups (alkyl to heterocyclic groups) may contain further substituents, e.g. B.

those of the aforementioned type and where the aforementioned alkyl, alkenyl, Cycloalkyl, aryl and heterocyclic groups either directly or through one the following divalent connecting links are attached: -O-, -S-, -S02-, -S02-NR-, NR-S02-, -NR-CO-, -CO-NR-, -NR-COO-, -O-CO-NR-, -NR-CO-NR- (R = hydrogen or alkyl).

The in formula III in the radicals represented by R2, R3, R4 or in the substituents present on the aromatic ring represented by R1 contained alkyl or alkenyl groups can be straight o # the branched and 1 - Contains 22 carbon atoms.

An amino group represented by R2, R3 or R4 or present as a substituent in R1 corresponds to the formula where R5 and R6 are identical or different and are hydrogen, alkyl or aryl or the ring members required to complete a 5- or 6-membered cyclic amino group (example: pyrrolidino, piperidino, morpholino).

The entirety of the substituents present in the ED compound is preferably such that the ED compound does not diffuse into photographic Layers can be stored. For this purpose, for example, at least one of the substituents present to bo at least one of the radicals Ra, R2, R3 and a, or a substituent on one of at least two of the radicals mentioned, e.g. B. by R3 and R4, completed ring contain a ballast residue.

Furthermore, it is important for the method of the invention that the The silver halide emulsion used would change under the actual developing conditions used can develop as quickly as possible. Useful silver halide emulsions are those during development, at least 80% of those maximum within 30 s Result in blackening (density) which is obtained after 2 min. Preferred is such However, blackening is already retained at development times of around 10 s. Are silver chloride, Silver bromides and silver chlorobromide emulsions, which in addition still up to May contain 10 moles of silver iodide.

For the production of colored aquidensitic images according to the process of the present invention is a so-called one besides the photosensitive member Pictorial Catching element required, in which by the pictorial Transfer of the released dyes creates the desired aquidensitic color image will. For this it is necessary that between the photosensitive element and the image receiving element at least for a finite period of time the development time there is firm contact, so that the in the photosensitive Element as a result of the development generated imagewise distribution of diffusible Dyes can be transferred to the image receiving element. The contact can after development has been started, or he may have been made before development begins. The latter is for example the case if to carry out the method according to the invention a so-called integral recording material is used in which the light-sensitive Element and the image receiving element form an integral unit, hereinafter also referred to as mono-sheet material, which continues after the end of the development process can continue to exist if a separation of the photosensitive element is not provided by the image receiving element even after the color transfer has taken place. One Such an embodiment is described, for example, in DE-OS 2 019 # 430.

The image receiving element can therefore be part of the color photographic Be recording material, e.g. B. in the form of a diffusible anionic Dyes dyeable # image-receiving layer that is below or above the photosensitive Element is arranged on a transparent layer support, with expedient moderately between the image-receiving layer and the photosensitive element an opaque, preferably light-reflecting binder layer is located The image-receiving layer, but also in another embodiment of the method according to the invention can be arranged on a separate carrier (image receiving sheet), consists essentially from a binder, the mordant for fixing the out of the non-diffusing Contains color releasers released, diffusible dyes. As a pickling agent long-chain quaternary ammonium or quaternary ammonium are preferably used for anionic dyes Phosphonium compounds, e.g. B. those as described in US 3,271,147 and US Pat. No. 3,271,148. Furthermore, certain metal salts and their hydroxides which form sparingly soluble compounds with the acidic dyes, are used. Polymeric mordants should also be mentioned here, such as those described in DE-OS 2 315 304, DE-OS 2 631 521 or DE-OS 2 941 818 describes the dye mordants are dispersed in the mordant layer in one of the usual hydrophilic binders, e.g.

in gelatin, polyvinylpyrrolidone, wholly or partially hydrolyzed Cellulose esters. Of course, some binders can also be used as a pickling agent act; z. B.

Copolymers or polymer mixtures of vinyl alcohol and N-vinylpyrrolidone, as described, for example, in DE-AS 1 130 284, also those, the polymers of nitrogen-containing quaternary bases; z. B.

Polymers of N-methyl-2-vinylpyridine, as described, for example in US 2,484,430. Other useful pickling binders are, for example, guanylhydrazone derivatives of alkyl vinyl ketone polymers, such as described in US 2,882,156, or guanylhydrazone derivatives of acylstyrene polymerization such as for example, in DE-OS 2 009 498. In general, however, you will last mentioned binding agents other binding agents, e.g. B. gelatin, add.

In addition, the image receiving layer or one adjacent to it Layer contain heavy metal ions, especially copper or nickel ions, if in the development of diffusible dyes that can be complexed by heavy metal ions or dye precursors are released. The metal ions can be in the image receiving layer be in complex bound form, e.g. B. bound to certain polymers such as for example described in Research Disclosure 18 534 (Sept. 1979) or in DE-OS 30 02 287.

Provided that the image receiving layer has been developed in Layer contact with the photosensitive element is left between they usually have an alkali-permeable, pigment-containing, light-reflecting binder layer, that of the optical separation between the light-sensitive element and the image-receiving layer and serves as an image background for the transferred colored equidensite image. One such a light-reflecting layer can already be used in a known manner in the color photographic Recording material be preformed or only in a known manner generated during development.

If the image-receiving layer is between the support and the light-sensitive Element is arranged and from the latter by a pre-formed light reflective If the layer is separated, either the support must be transparent be, so that the generated squidensite image can be viewed through it, or the light-sensitive element must be together with the light-reflecting layer be removed from the image-receiving layer to form the equidensitivity image formed in the latter to expose. The image receiving layer can also be used as the top layer in one integral color photographic recording material be available, in which the latter If the exposure is expediently carried out through the transparent support will.

The color photographic recording material used according to the invention can also have acidic layers and so-called braking or retardation layers which together form a so-called integral neutralization system. Such an integral neutralization system can in a known manner between the Layer support and the image-receiving layer arranged thereon or at another point in the layer structure, e.g. B. above the photosensitive Layers, d. H. beyond these light-sensitive layers, from the image-receiving layer viewed from. The neutralization system is usually oriented so that the braking or deceleration layer is located between the acid layer and the point, on which a liquid or pasty alkaline developer preparation for action is brought. Such acid layers, braking layers, etc.

from both existing neutralization systems are for example known from US 2 584 030, US 2 983 606, US 3 362 819, US 3 362 821, DE-OS 2 455 762, DE-OS 2 601 653, DE-OS 2 652 464, DE-OS 2 716 505, DE-OS 2 816 878. Such a neutralization system can, in a known manner, also have two or more Brake layers included.

The development is in the method according to the invention with a Aqueous alkaline developer preparation carried out, using as developer substances a 1-phenyl-3-pyrazolidone derivative and a compound of the general formula I. are present. The developer substances can either be in the developer preparation be contained or also completely or partially in one or more layers of the color photographic recording material or a non-light-sensitive one Be stored in the image receiving sheet. Especially when storing in layers of the color photographic recording material, it turns out to be an improvement the stability of the materials as favorable, developing substances with protective groups to use, which can easily be split off in an alkaline medium.

1-Phenyl-3-pyrazolidone, for example, can be used as developer component A, 1-phenyl-4, 4-dimethyl-3-pyrazolidone, 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone, 1-phenyl-4-methyl-3-pyrazolidone, 1-phenyl-5-methyl-3-pyrazolidone, 1-phenyl-4,4-bis- (hydroxymethyl) -3-pyrazolidone, 1- (3-chlorophenyl) -4-methyl-3-pyrazolidone, 1- (4-chlorophenyl) -4-methyl-3-pyrazolidone, 1- (3-chlorophenyl) -3-pyrazolidone, 1- (4-chlorophenyl) -3-pyrazolidone, 1- (4-tolyl) -4-methyl-3-pyrazolidone, 1- (4-tolyl) -4-hydroxymethyl-4-methyl-3-pyrazolidone, 1- (3-tolyl) -3-pyrazolidone, 1- (3-tolyl) -4,4-dimethyl-3-pyrazolidone, including those Derivatives of 1-phenyl-3-pyrazolidone, which are present in masked form, for example acetylated phenidone derivatives.

As developer component B, for example, hydroquinone, pyrocatechol, p-aminophenol or p-phenylenediamine derivatives are possible. Derivatives are preferred of hydroquinone used, e.g. B. hydroquinone, 2-methylhydroquinone, 2-tert. -Butylhydroquinone, 2-tolylhydroquinone as well as polyalkylated hydroquinones. By the additional Use of hydroquinone apparently increases the development speed considerably increased, which is when using reducible dye releasers and ED compounds suitable reactivity surprisingly leads to the formation of aquidensites. Although the cause of this has not yet been fully clarified, the formation can be of the equidensites possibly interpret as follows.

The formation of a positive gradation in the color transfer image corresponds the usual functionality of the combination of reducible color releasers and ED compounds in connection with negative silver halide emulsions, d. H. ever the higher the exposure intensity, the more ED compound is created by silver halide developing agents consumed and the less dye can be due to reaction of the remaining ED compound can be released with the reducible paint releaser. With increasing exposure intensity therefore, the color density in the image receiving layer decreases. From a certain exposure intensity but the rate of development apparently increases when using the invention Developer combination considerably, so that for the developer oxidation product formed in the case of the comparatively inert masked used according to the invention ED-Ver bindings not fast enough enough free ED connection is available for abreaction. The developer oxidation product reacts in increasing degree in a different way, without this ED compound is oxidized.

From a certain exposure onwards, therefore, there is less and less ED compound consumed by reaction with developer oxidation, so that more and more ED compound can release dye through reaction with the dye releasing agent. This means that with increasing exposure, the color density in the image receiving layer increases (negative Gradation).

The gradation curve of the carry-over image therefore has a certain Exposure intensity a dip (color density minimum) on that of the equidensite corresponds (see. Fig. 1).

Example 1 A photosensitive element of a photographic recording material was produced by being on a transparent support made of polyethylene terephthalate the following layers were applied one after the other, the quantities given differing each based on 1 m2 1. A stain layer of 2.7 g of the compound A tpolyme re stain) and 2.7 g gelatin.

2 A white pigment layer made from 18.3 g TiO2 and 2.57 g gelatin.

3 A carbon black layer made of 1.87 g of carbon black and 2.06 g of gelatine '.

A red sensitized emulsion layer made from an iodide containing Silver chlorobromide emulsion (silver application 0.31 g AgN03) with 0.94 g gelatin, 0.29 g of compound B (cyan dye releaser) and 0.16 g of compound C (ED compound; # 1/2 = 1.1 s).

5th layer of 0.2 g of 2-acetyl-5-octadecylhydroquinone and 1 g of gelatin.

6. A hardening layer of 0.06 g of Compound F (hardening agent) and 0.6 g gelatin.

With otherwise the same layer arrangement, a further layer structure was used compound C in layer 4 by 0.16 g of compound D (ED compound; > 1/2 = 1.6 s).

Finally, a third layer structure was used with otherwise the same Layer arrangement in layer 4 0.18 g compound E (ED compound; 1/2 = 4t5 s) used.

The photosensitive materials were developed with a Paste of the following composition 40 g KOH 8 g 4-methyl-4-hydroxymethyl-phenidone 3 g potassium bromide 2 g sodium sulfite 1 g 5-methylbenzotriazole 10 ml 1-phenyl-propanol-3 40 g carboxymethyl cellulose (7 fl 3 SCF from Fa.

Hercules) 354 g carbon black dispersion (TAN 316-45 / 200 from

Degussa) 556 g of water The paste also has an additional 0.5 g, 1.0 g and 5 g of methylhydroquinone in each case added per kg of paste.

To neutralize the image material after development, a Cover sheet made from a substrate made of polyethylene terephthalate with the following coating used.

The quantities given relate to 1m2 1. An acidic polymer layer made of 16 g of acrylic acid / butyl acrylate copolymer (W / W 70/30).

2. A braking layer made from 2.1 g cellulose diacetate, 0.16 g styrene / maleic anhydride copolymer and 0.18 g of compound G (stabilizer precursor, precursor compound).

3. A second braking layer made of 2.2 g of a latex, consisting of vinylidene chloride / methyl acrylate / itaconic acidX Copolymer (W / W 55/39/6).

After imagewise exposure, one sheet each became the photosensitive Recording materials with a cover sheet over two laterally attached spacers about 100 µm thick brought into contact with a container with developer paste at one end was attached. The image set thus formed was passed through a pair of nip rollers, wherein the developer paste is located between the light-conducting element and the cover sheet distributed. Through the transparent substrate on the TiO2 layer as a background Colored images of the original were visibly obtained.

An overview of the sensitometric data of the three layer structures depending on the developer variants are listed in Table 1. The gradation curve obtained with Experiment No. 11 is shown in FIG.

Table 1 No. ED- t1 / 2 MHQ iegativgrada- positive gradation tion Conn. [S] g / kg Dmin / Dmax E Dmin / Dmax 1 E #E paste 1 C 1.1 - -, - - 0.70 / 1.45 1.73 - 2 0.5 -, - - 0.52 / 1.45 1.72 - 3 1.0 -, - - 0.56 / 1.50 1.75 - 4 5.0 0.85 / 0.90 - 85 / 0.90 0.85 / 1.59 2.15- - 5 D 1.6 - -, - - ~ 0.15 / 1.54 2.05 - 6 0.5 -, - - 0.18 / 1.48 2.21 - 7 1.0 0.18 / 0.32 - 0.18 / 1.5? 2.27 - 8 - 5.0 0.45 / 1.00 0.85 0.45 / 1.58 2.38 1.53 9 E 4.5 - -, - - 0.15 / 1.72 2.25 - 10 0.5 0.19 / 1.50 1.2 (0.19 / 1.67 2.27 1.07 11 1.0 0.19 / 1.72 1.3 0.19 / 1.72 2.28 0.98 - 12 5.0 0.49 / 1.75 1.4 0.49 / 1.50 2.43 1.03 # 1/2 [s]: Half-life of oxidized 1-p-tolyl-4-methyl-4-hydroxymethyl-3-pyrazolidone on reduction by ED compound. The smaller the number, the more active the ED connection.

MHQ: methyl hydroquinone Dmin / Dmax: measured behind Red filter E: relative photographic sensitivity measured in log I.t units at D = (Dmax-Dmin) x 0.5 + Dmin As can be seen from Table 1, in the development normal positive wedges obtained without methylhydroquinone (MHQ). If you put the developer Methylhydroquinone to, so with increasing amount of MHQ is increasing in addition the positive gradation also built a negative gradation.

The prerequisite is that the ED compound does not have too high a reactivity owns. While the ED compound C with the highest reactivity (~ 1 ~ 2 = 1.1 s) showed practically no negative image, the ED showed compounds D and E, in decreasing reactivity, increasingly more pronounced an equidensitic pattern. In this way it is possible to use only one silver halide emulsion in one development step generate a colored equidensite image.

Formula appendix Compound A x = 49 mol% Y = 49 mol% Z = 2 mol% ED connections Connection C Connection D Connection E Connection F Connection G Blank page

Claims (4)

A method for the photographic production of color equidensites, characterized in that a color photographic recording material with a light-sensitive element arranged on a layer support, the at least one negative silver halide emulsion layer and a combination associated therewith of a reducible dye releaser and an ED compound with one according to that in the description specified method contains a certain half-life of 1.6 to 20 s, exposed imagewise-1/2 and in the presence of a developer combination, consisting of A) a 1-phenyl-3wpyrazolidonderivat and B) a compound of the following general formula I where mean: Q is a radical to complete a benzene ring optionally containing further substituents n 0 or 1 R¹, R is hydrogen, alkyl or aryl R¹, R is hydrogen, alkyl or both together a radical to complete a cyclic amino group, is developed with an alkaline developer preparation, and that the diffusible dye released in imagewise distribution from the dye releaser during development is transferred by diffusion transfer into an image-receiving layer which can be dyed by diffusible anionic dyes. 2. The method according to claim 1, characterized in that the developer component B methylhydroquinone is used. 3. The method according to claim 1 or 2, characterized in that a compound of the following general formula II is used as a reducible dye releaser in which R1 is alkyl or aryl; R is alkyl, aryl or a group which, together with R3, completes a fused ring; R³ is hydrogen, alkyl, aryl, hydroxyl, halogen, amino, alkylamino, dialkylamino including cyclic amino groups, acylamino, alkylthio, alkoxy, aroxy, sulfo, or a group which, together with R, completes a fused ring; 4 R alkyl; R5 is hydrogen; A is the remainder of a diffusible dye or dye precursor; X is a bivalent link of the formula -R- (L) p- (R) q-, where R is an alkylene radical having 1-6 carbon atoms or an optionally substituted arylene or aralkylene radical and the two radicals R have the same meaning or can have different meanings from one another; L -O-, -CO-, -CONR6-, -SO2NR6 -O-CO-NR6 -S-, -SO- or 502 (R6 = hydrogen or alkyl); p 0 or 1; q 0 or 1; m 0 or 1, and where at least one of the radicals R1, R2, R3, R4 contains a ballast radical. 4. The method according to claim 3, characterized in that a hydroquinone lactone of the following general formula III is used as the ED compound wherein R1 is a carbocyclic or heterocyclic aromatic ring; R, R³, R4 identical or different substituents, namely hydrogen, alkyl, alkenyl, aryl, alkoxy, alkylthio, amino or R3 and R4 together complete a fused, in particular carbocyclic ring.