EP0012908A2 - Photographic colour diffusion transfer process and photographic recording material suitable therefor - Google Patents

Abstract

The oxidisable colouring compounds in the colour photographic recording material for the dye diffusion transfer process are nondiffusing compounds of the following formula: <IMAGE> where A is a photographically active group, for example a dye radical, X is a bridge member, m is 0 or 1, Y<1> and Y<2> are groups which are oxidisable to form a p-quinonoidal system, R<1> is a hydrocarbon radical, R<2> is H or a hydrocarbon radical, R<3> is a substituent such as R<2>, a grouping which together with R<4> completes a ring, OH, halogen, amino, acylamino, alkylthio, alkoxy, aroxy or sulpho, R<4> is a hydrocarbon radical or a grouping which together with R<3> completes a ring, R<5> is a hydrocarbon radical.h

Description

The invention relates to a process for producing color photographic images by the dye diffusion transfer process and to a photographic material suitable therefor which contains new diffusion-resistant, oxidizable coloring compounds which release diffusing dyes in a non-oxidized form.

Among the processes known to date for the production of colored photographic images by the color diffusion transfer process, those based on the use of diffusion-resistant embedded coloring compounds, from which diffusing dyes or dye precursor products are separated imagewise during development and transferred to an image-receiving layer, have recently become increasingly important . The color-providing compounds suitable for this purpose include, for example, the non-diffusing color couplers described in DE-PS 1 095 115, which are used in the Development as a result of a reaction with the oxidation product of a color developer compound consisting of a primary aromatic amine releases a pre-formed or diffused form of dye produced in the color coupling. The selection of the developer compound required is naturally limited to color developers.

Furthermore, reference should be made to the non-diffusing coloring compounds described in DE-OS 1 930 215, which contain a preformed latent diffusible dye residue linked to a diffusion-proofing residue via a cleavable hydrazone group. These compounds are not to be called color couplers, and it has also been found that the choice of developer compounds which are required to release the diffusing dye residue is in no way limited to the usual color developers, but that black and white developers, e.g. Catechins are very useful.

DE-OS 1 772 929 also describes non-diffusing colored compounds with a special grouping which undergo an oxidative ring closure reaction during development and thereby release a pre-formed dye residue in diffusing form. The connections presented there can be divided into two groups. The compounds of the one group require a customary color developer compound for development, with whose oxidation product they couple and in a subsequent ring closure reaction release the pre-formed dye residue in diffusing form. The compounds of the other group are themselves slip halide developing agents and are therefore able, in the absence of further developer compounds in the oxidustan form, to undergo the above-mentioned ring closure reaction with fralse tion of the diffusing dyes.

Finally, the non-diffusing coloring compounds of DE-OS 2 242 762 should also be mentioned at this point. These are sulfonamidophenols and sulfonamidoanilines, which after development have undergone oxidation under the influence of the developer alkali with the release of diffusing dyes with a free sulfamoyl group will.

The above-mentioned coloring compounds work invariably negative, i.e. the image-wise distribution of the diffusing dye set arises when conventional (negative working) silver halide emulsions are used in accordance with the negative silver image produced during development. To produce positive finished fabric images, it is therefore necessary to use direct-positive silver halide emulsions or otherwise to use a suitable reversal process.

Non-diffusing coloring compounds are also known from German Offenlegungsschriften 2 402 900 and 2 543 902, which, in non-oxidized form, are capable of a cleavage reaction under alkaline development conditions, a diffusing color step being set free, and in which, on the other hand, in the oxidized form the one mentioned above Cleavage reaction is difficult or prevented. Such compounds are suitable in combination with conventional negative emulsions for producing positive transfer color images

worin bedeuten:

• A eine fotografisch wirksame Gruppe, die zusammen mit dem Bindeglied -Z-(X)_m- unter alkalischen Bedingungen aus der nicht oxidierten Form der oxidierbaren Verbindung abgespalten wird;
• Y¹ und Y² (gleich oder verschieden) Gruppen, die aufgrund ihrer Wechselwirkung miteinander oxidierbar sind unter Ausbildung eines p-chinoiden Systems;
• R¹ einen gegebenenfalls substituierten Kohlenwasserstoffrest;
• R² Wasserstoff oder einen gegebenenfalls substituierten Kohlenwasserstoffrest;
• R3 R⁴ und R⁵ (gleich oder verschieden) Wasserstoff, Halogen, Alkyl oder Alkoxy mit bis zu 18 C-Atomen, _Acy_la_mi_no oder _R ³ zusammen mit R⁴ den zur Vervollständigung eines ankondensierten, gegebenenfalls substituierten Kohlenwasserstoffringes erforderlichen Rest

und wobei mindestens einer der Substituenten R¹, R³, R⁴ und R⁵ einen diffusionsfest machenden Rest enthält.Another class of non-diffusing oxidizable compounds, which predominantly only release from the non-oxidized form of diffusing dyes, is the subject of German patent application P 28 23 159.6. The compounds described there are essentially those of the following formula:

in which mean:

• A is a photographically active group which, together with the link -Z- (X) _m - is split off from the unoxidized form of the oxidizable compound under alkaline conditions;
• Y ¹ and Y ² (identical or different) groups which, owing to their interaction with one another, can be oxidized to form a p-quinoid system;
• R ^{1 is} an optionally substituted hydrocarbon residue;
• R ^{2 is} hydrogen or an optionally substituted hydrocarbon radical;
• R3 R ⁴ and R ⁵ (same or different) hydrogen, halogen, alkyl or alkoxy having up to 18 C atoms, _Ac y _l a _m i _no or _R ³ together with R ⁴ the to complete a fused, optionally substituted hydrocarbon ring required rest

and wherein at least one of the substituents R ¹ , R ³ , R ⁴ and R ^{5 contains} a diffusion-resistant radical.

With the compounds described in the aforementioned German patent application P 28 23 159.6, positive colored transfer images can be generated using conventional negative-working silver halide emulsions, but these still have a certain color haze, which indicates that the combinations used in the oxidized state are not sufficiently stable are to be protected against subsequent splitting under the alkaline, development conditions. However, color-imparting compounds of the type described are desirable which are completely stable in oxidized form under the development conditions.

In the further processing of this technical field, it has now been found that much more favorable results are achieved, that is to say compounds whose oxidized form is more stable against alkaline cleavage if those compounds are selected from the substance class described in the aforementioned German patent application in which neither in the (free) o- nor in the p-position to the carbon atom bearing the cleavable radical -S0 ₂ - (X) _m- A is there a deprotonatable group such as -OH or -NH ₂ or can arise in an alkaline developer environment. It should be noted that one of the two o-positions to the said carbon atom is

must be substituted with such a group, which, together with a second group of the same type, enables the formation of a p-quinoid system upon oxidation. It is important that positions 2 and 4 of the above formula contain neither a hydrogen atom nor a substituent which can be exchanged for OH ions.

worin bedeuten:

• A den Rest einer fotografisch wirksamen Gruppe, insbesondere den Rest eines diffundierenden Farbstoffes oder Farbstoffvorproduktes;
• X ein bivalentes Bindeglied der Formel -R-(L)_p-(R)_q-, worin R einen Alkylrest mit 1-6 C-Atomen oder einen gegebenenfalls substituierten Arylen- oder Aralkylenrest bedeutet und wobei die beiden Reste R die gleiche oder einer verschiedene Bedeutung haben können;
• L -0-, -CO-, -CONR⁶-, -SO₂NR⁶-, -O-CO-NR⁶-, -_S-, -SO- oder -S0₂- (R = Wasserstoff oder Alkyl),
• p 0 oder 1;
• q 0 oder 1;
• m 0 oder 1; Y¹ und Y² (gleich oder verschieden) Gruppen oder Vorläufer von Gruppen, die aufgrund ihrer Wechselwirkung miteinander oxidierbar sind unter Ausbildung eines p-chinoiden Systems, beispielsweise -OR⁷--NHR⁷, -NH-R⁸, -N(R⁸)₂ oder -NH-SO₂-R⁸, worin R⁷ für Wasserstoff oder eine unter den alkalischen Entwicklungsbedingungen hydrolysierbare fotografisch inerte Gruppe steht und R⁸ für einen beliebigen organischen fotografisch inerten Rest steht, der über ein C-Atom mit dem N-Atom bzw. der -S0₂-Gruppe verbunden ist, vorzugsweise für Alkyl, insbesondere Niederalkyl mit 1 - 4 C-Atomen, oder Aryl, insbesondere Phenyl oder Tolyl; Y² ist jedoch nicht eine disubstituierte. Aminogruppe -N(R⁸)₂;
• R einen gegebenenfalls substituierten Kohlenwasserstoffrest, z.B. Alkyl mit bis zu 2₂ C-Atomen, wie Methyl, Ethyl, n-Hexyl, n-Octyl, n-Undecyl, n-Dodecyl, n-Tridecyl, n-Heptadecyl, Aralkyl wie Benzyl oder Aryl wie Phenyl;
• R² Wasserstoff oder einen gegebenenfalls substituierten Kohlenwasserstoffrest, z.B. Alkyl mit bis zu 22C-Atomen, wie Methyl, Ethyl, Propyl, Isopropyl, n-Hexyl, n-Octyl, n-Undecyl, n-Dodecyl, n-Tridecyl, n-Heptadecyl, Aralkyl wie Benzyl, oder Aryl wie Phenyl;
• R³ einen Substituenten wie für R² definiert, eine Gruppierung, die zusammen mit R⁴ einen ankondensierten heterocyclischen oder carbocyclischen, gegebenenfalls aromatischen Ring vervollständigt oder OH, Halogen wie Chlor oder Brom, Amino, Alkylamino, Dialkylamino einschließlich cyclischer Aminogruppen (wie Piperidino, Morpholino), Acylamino, Alkylthio, Alkoxy, Aroxy oder Sulfo;
• R⁴ einen gegebenenfalls substituierten Kohlenwasser. stoffrest, z.B. Alkyl mit bis zu 22 C-Atomen, Aralkyl wie Benzyl, Aryl wie Phenyl oder eine Gruppierung, die zusammen mit R³ einen ankondensierten heterocyclischen oder carbocyclischen, gegebenenfalls aromatischen Ring vervollständigt, z.B. einen ankondensierten Benzol- oder 2-Bi- cyclo[2,2,1]hepten-Ring;
• R⁵ einen gegebenenfalls substituierten Kohlenwasser. stoffrest, z.B. Alkyl, Aralkyl oder Aryl, vorzugsweise n-Propyl,

und wobei mindestens einer der Substituenten R¹, R³, R und R⁵ einen diffusionsfest machenden Rest enthält.The invention relates to a photographic diffusion transfer process in which a photographic material with at least one light-sensitive silver halide emulsion layer and an associated non-diffusing oxidizable compound, which in non-oxidized form is subject to a cleavage reaction under the conditions of alkaline development with the release of a photographically active group, for example a diffusing dye , and which is not or only to a much lesser extent subject to the above-mentioned cleavage reaction in oxidized form than in non-oxidized form, is imagewise exposed and is developed with a silver halide developing agent, the silver halide developing agent oxidizing the non-diffusing oxidizable compound in oxidized form and thereby not or by an alkali only slightly cleavable form, while from the imagewise distribution of non-oxidized oxidizable compound as a result of cleavage alkali releases the photographically effective group. If the photographically active group is a diffusing dye, this can be transferred to an image-receiving layer. In the latter case, the non-diffusing compounds are referred to below as coloring compounds. The process is characterized in that a compound of the following formula is used as the non-diffusing oxidizable compound:

in which mean:

• A the rest of a photographically active group, in particular the rest of a diffusing dye or dye precursor;
• X is a bivalent link of the formula -R- (L) _p - (R) _q -, in which R is an alkyl radical with 1-6 C atoms or an optionally substituted arylene or aralkylene radical and where the two radicals R are the same or one can have different meanings;
• L -0-, -CO-, -CONR ⁶ -, -SO ₂ NR ⁶ -, -O-CO-NR ⁶ -, - _S -, -SO- or -S0 ₂ - (R = hydrogen or alkyl),
• p 0 or 1;
• q 0 or 1;
• m 0 or 1; Y ¹ and Y ² (identical or different) groups or precursors of groups which can be oxidized due to their interaction with one another to form a p-quinoid system, for example -OR ⁷ --NHR ⁷ , -NH-R ⁸ , -N (R ⁸ ) ₂ or -NH-SO ₂ -R ⁸ , wherein R ^{7 is} hydrogen or a photographically inert group which can be hydrolyzed under the alkaline development conditions and R ^{8 stands} for any organic photographically inert radical which is connected via a carbon atom to the nitrogen atom or the --SO ₂ group, preferably for alkyl, in particular lower alkyl 1 - 4 carbon atoms, or aryl, especially phenyl or tolyl; However, Y ² is not a disubstituted one. Amino group -N (R ⁸ ) ₂ ;
• R is an optionally substituted hydrocarbon radical, for example alkyl having up to 2 ₂ carbon atoms, such as methyl, ethyl, n-hexyl, n-octyl, n-undecyl, n-dodecyl, n-tridecyl, n-heptadecyl, aralkyl such as benzyl or Aryl such as phenyl;
• R ^{2 is} hydrogen or an optionally substituted hydrocarbon radical, for example alkyl having up to 22C atoms, such as methyl, ethyl, propyl, isopropyl, n-hexyl, n-octyl, n-undecyl, n-dodecyl, n-tridecyl, n-heptadecyl , Aralkyl such as benzyl, or aryl such as phenyl;
• R ^{3 is} a substituent as defined for R ² , a grouping which together with R ^{4 completes} a fused-on heterocyclic or carbocyclic, optionally aromatic ring or OH, halogen such as chlorine or bromine, amino, alkylamino, dialkylamino including cyclic amino groups (such as piperidino, morpholino ), Acylamino, alkylthio, alkoxy, aroxy or sulfo;
• R ^{4 is} an optionally substituted hydrocarbon. material residue, for example alkyl with up to 22 carbon atoms, aralkyl such as benzyl, aryl such as phenyl or a group which together with R ^{3 completes} a fused-on heterocyclic or carbocyclic, optionally aromatic ring, for example a fused-on benzene or 2-bicyclo [2,2,1] hepten ring;
• R ^{5 is} an optionally substituted hydrocarbon. residual material, for example alkyl, aralkyl or aryl, preferably n-propyl,

and wherein at least one of the substituents R ¹ , R ³ , R and R ^{5 contains} a diffusion-resistant radical.

The present invention furthermore relates to a material for carrying out the above method, which accordingly, in association with at least one light-sensitive silver halide emulsion layer, contains a non-diffusing oxidizable compound of the type described above.

In principle, the residues of dyes of all classes of dyes are suitable as dye residues insofar as they are sufficiently diffusible to be able to diffuse through the layers of the light-sensitive material into the image-receiving layer. For this purpose, the dye residues can be provided with one or more water-solubilizing groups. Suitable water-solubilizing groups include carboxyl groups, sulfo groups, sulfonamide groups and aliphatic or aromatic hydroxyl groups. The sulfinic acid group remaining in the dye after the cleavage can already give the dye molecule a considerable tendency to diffuse in the alkaline Medium, so that the presence of additional water-solubilizing groups is not absolutely necessary. Examples of dyes which are particularly suitable for the process according to the invention include azo dyes, azomethine dyes, anthraquinone dyes, phthalocyanine dyes, indigoid dyes, triphenylmethane dyes and metal complex dyes or colored metal complexes.

The residues of dye precursors are to be understood as the residues of those compounds which, in the course of photographic processing, are subject to conventional or additional processing steps, be it by oxidation, by coupling or by exposure of an auxochromic group in a chromophoric system, for example by saponification Dyes are transferred. Dye precursors in this sense can be leuco dyes, couplers or dyes that are converted into other dyes during processing. Unless a distinction between dye residues and the residues of dye precursors is of essential importance, the latter are also to be understood below as dye residues.

Y¹ und Y² haben vorzugsweise die Bedeutung Hydroxyl. Fllas Y¹ und/oder Y² eine -NH-S02R8-Gruppe bedeutet, hat R⁸ aweckmäßigerweise die Bedeutung eines fotografisch inerten Restes, z.B. eines unsubstituierten Alkyl- oder Phenylrestes.The bivalent link X shown in the general formula can, for example, be a radical of one of the following formulas:

Y ¹ and Y ² are preferably hydroxyl. If Y ¹ and / or Y ^{2 is} an -NH-S02R8 group, R ⁸ has the meaning of a photographically inert radical, for example an unsubstituted alkyl or phenyl radical.

It goes without saying that, within the group of the oxidizable compounds of the general formula, some are more suitable than others. For example, the redox potential of the oxidizable compound can easily be influenced by varying the substituent R ³ and can thus be adapted to practical requirements. It has already been pointed out that the selection of the substituents R ⁴ and R ⁵ is subject to certain restrictions, insofar as hydrogen or other substituents which can be exchanged for OH ^- ions are out of the question. However, this does not apply to R ³ to the same extent, so that a larger selection of substituents is available here for setting the desired redox potential. In addition to the oxidizability, another important function of the compounds according to the invention is the easy hydrolyzability in the unoxidized form. The hydrolytic cleavage should proceed as quickly as possible in the alkaline developer medium so that the photographically active group is quickly released. On the other hand, the onset of hydrolytic cleavage should be delayed until the imagewise oxidation of the oxidizable compounds by developer oxidation products has essentially been completed. The rate of hydrolytic cleavage must therefore be matched to the rate of oxidation and this can easily be achieved by varying the substituents which have a great influence on the hydrolyzability. This is influenced, among other things, by the nature of the link (x) _m , in the first Line however through the nature of the substituents, R, R and Y ² within the given definition. If Y ₂ = OH, R is, for example, preferably hydrogen. It should be noted that the coloring compounds according to the invention should not diffuse as intact molecules in the layers of the photographic material. For this purpose, they contain a radical which makes them resistant to diffusion, for example in one of the substituents R to R or in a substituent present on the fused ring completed by R together with R 4.

Adequate diffusion resistance of the coloring compounds can already exist even if the substituents mentioned do not contain any longer alkyl residues, since the molecule can then also have a sufficient size, depending on the dye residue. Otherwise it is possible to make the coloring compounds sufficiently diffusion-resistant by selecting residues of a suitable size.

Residues which make it resistant to diffusion are those which make it possible to store the compounds according to the invention in a diffusion-resistant manner in the hydrophilic colloids which are usually used in photographic materials. Organic radicals which generally contain straight-chain or branched aliphatic groups and optionally also isocyclic or heterocyclic or aromatic groups with generally 8-22 C atoms are preferably suitable for this purpose. These residues are connected to the rest of the molecule either directly or indirectly, for example via one of the following groups: -NHCO-, NHSO ₂ , -NR-, where R is hydrogen or alkyl, -O-, -S- or -SO ₂ , such groups containing such hetero atoms expediently by at least two carbon atoms or methylene groups of the aromatic ring of the general formula ( R ³ , R ⁴ , R ⁵ ) or from the carbon atom (R ¹ ) bearing the cleavable group -SO ₂ - (X) _m -A). In addition, the diffusion-proofing radical can also contain water-solubilizing groups, such as sulfo groups or carboxyl groups, which can also be in anionic form. Since the diffusion properties depend on the molecular size of the total compound used, it is sufficient in certain cases, for example if the total molecule used is large enough, to use shorter-chain residues as "diffusion-proofing residues".

Examples of non-diffusing oxidizable compounds suitable according to the invention are listed below:

Production Example I Compound No. 1 Step 1: 2,3-dimethyl-6-tetradecanoyl hydroquinone

Boron trifluoride was introduced into a mixture of 138 g (1 mol) of 2,3-dimethylhydroquinone 370 g (1.62 mol) of myristic acid and 700 ml of methylene chloride under vigorous reflux (bath temperature 50 ° C.) until saturation. After standing overnight, the reaction mixture was decomposed by stirring in 3 1 10% Na acetate solution. The methylene chloride was removed with steam. After cooling, the remaining oily layer solidified to a melt cake which was isolated by decanting. The melt cake was then melted and stirred into 2 liters of high-boiling gasoline. The precipitate was filtered off and washed with gasoline (50 - 70 ° C). After drying, the mixture was stirred with acetonitrile and suction filtered.

Yield: 260 g / F 100-101 ° C Step 2: 4-hydroxy-2,3-dimethyl-6-tetradecanoylphenyl allyl ether

To a mixture of 105 g of ketone from stage 1, 63 g of potassium carbonate and 1200 ml of methyl ethyl ketone were added dropwise 43 g of allyl bromide with gentle boiling over the course of 2 hours. After 9 hours of boiling, the mixture was cooled to 30 ° C. and 200 ml of water were added.

The aqueous layer was separated. The organic light was shaken out once with 25% sodium chloride solution, separated off and the solvent was distilled off. The residue was stirred with 1 l of methanol and suction filtered.

Yield: 95 g / F 65-66 ⁰ C

Step 3: 2,3-dimethyl-5-allyl-6-tetradecanoyl hydroquinone

90 g of allyl ether from stage 2 were heated to 210 ° C. in the course of 2 hours under a nitrogen atmosphere. After cooling, the melt was dissolved in 300 ml of gasoline (50-75 ° C) and cooled. The next day, the resulting precipitate was suctioned off.

Yield: 73 g / F 68 - 69 ⁰ C Step 4: 2,3-dimethyl-5-propyl-6-tetradecanoyl hydroquinone

16.2 g of the allyl compound from stage 3 were dissolved in 165 ml of alcohol and hydrogenated in the presence of Raney nickel under normal conditions. After removal of the Raney nickel, the alcohol was distilled off and the residue was crystallized from 300 ml of gasoline.

Yield: 15 g / F 69-70 ° C

Step 5: 2,3-dimethyl-5-propyl-6-α-hy3roxytetradecylhydroquinone

₁ 4 g of the keto compound from stage 4 was dissolved in 390 ml of methanol and added slowly with stirring in a nitrogen atmosphere with a solution of 1.97 g of sodium borohydride in 24 ml of water. After 30 minutes, the mixture was gently acidified with glacial acetic acid places and stirred in a solution of 2.5 ml of sulfuric acid in 270 ml of water. The precipitate was filtered off and recrystallized from methanol.

Yield: 10.5 g / F 140-142 ° C

Step 6: dye sulfinic acid 4- (4-hydroxy-3-N, N-diethylsulfamoyl-8-methylsulfonamido-1-naphthylazo) -benzenesulfinic acid

Under a nitrogen atmosphere, 11.5 g of Na salt of 4-amino-benzenesulfinic acid and 4.4 g of sodium nitrite were added. 70 ml of water dissolved, mixed with 85 g of crushed ice and mixed with 18 ml of concentrated hydrochloric acid with stirring. The diazonium salt solution was immediately stirred in one solution into a solution of 25 g of 1-hydroxy-2-N, N-diethylsulfamoyl-5-methylsulfonamido-naphthalene, 23.15 g of sodium carbonate, 130 ml of water and 45 ml of acetone. After 30 minutes, the dye solution was stirred into 200 ml of glacial acetic acid and the dye which had precipitated was filtered off with suction. After drying in a vacuum desiccator, 32 g of crude dye remain, which was used without purification for the reaction to compound 1.

Level 7: Connection 1

A solution was added to a solution of 4 g of the carbinol compound from stage 5 in 300 ml of glacial acetic acid heated to 60 ° C. of 7 g of dye sulfinic acid from stage 6 1.5 g of Na acetate anhydrous 120 ml of glacial acetic acid and 40 ml of water. The mixture was heated to 90 ° C. for 2 hours while stirring in a nitrogen atmosphere. After a short time, the dye compound begins to fail. After cooling to 60 ° C, the resulting precipitate was filtered off and washed with glacial acetic acid. The dye was purified by stirring with methanol.

Yield: 5.6 g Production Example II

Compound No. 11

Step 1: 2-methyl-5-hexadecanoyl hydroquinone

13.7 g of 2-methylhydroquinone and 45 ml of methylene chloride were passed into a mixture of 27.2 g of palmitic acid with vigorous reflux until saturation of boron trifluoride. After standing overnight, the mixture was boiled under reflux for a further hour and then decomposed in a solution of 25 g of Na acetate in 220 ml of water with stirring. After 45 minutes, the methylene chloride solution was separated and evaporated. The residue was stirred with methanol and suction filtered.

Recrystallized from n-chlorobutane, 21 g were obtained at F 90-93 ° C

Step 2: 4-Hydroxy-2-methyl-5-hexadecanoylphenyl allyl ether

6.9 g of allyl bromide were added to a mixture of 17.5 g of the keto compound from stage 1, 10.2 g of potassium carbonate and 200 ml of methyl ethyl ketone with stirring and refluxing in the course of 60 minutes under a nitrogen atmosphere. After a total of 9 hours of refluxing, the reaction mixture was mixed with 100 ml of water. The methyl ethyl ketone layer was separated, shaken twice with 20% sodium chloride solution and dried with sodium sulfate. The residue which remained after evaporation of the solvent was stained with methanol and the resulting precipitate was recrystallized from methanol after suction.

Yield: 12.5 g / F 44-47 ° C

Step 3: 2-methyl-6-allyl-5-hexadecanoyl hydroquinone

12 g of allyl ether from stage 2 were subjected to the Claisen rearrangement as described in Preparation Example 1, stage 3. After cleaning with gasoline (50 - 75 ° C) 8.5 g yield with F 65 - 67 ° C were obtained.

Step 4: 2-methyl-6-propyl-5-hexadecanoyl hydroquinone

8 g of allyl hydroquinone from stage 3 were hydrogenated as described in preparation example 1, stage 4 and the product formed was also recrystallized from gasoline.

Yield: 6.5 g / F 66-68 ° C Mare 5: 2-methyl-6-propyl-5-α-hydroxy-hexadecylhydrochincn

6.5 g of the keto compound from stage 4 were dissolved in 90 ml of Methanel and hydrogenated with a solution of 0.75 g of sodium borohydride in 3 ml of water as described in Preparation Example 1, stage 5, and the crude carbinol was recrystallized from methanol.

Yield: 5 g / F 121 to 124 ⁰ C.

Step 6: dye sulfinic acid 4- {3- [8- (4-nitro-2-methylsulfonylphenylazo) -5-hydroxy-1-naphthyl] sulfamoylbenzene} sulfionamido benzene sulfinic acid

In a solution of 4.9 g of potassium carbonate, 3.75 g of aminobenzenesulfinic acid, 44 ml of water and 62.5 ml of acetone were mixed with 10 g of 3- [8- (4-nitro-2-methylsulfonylphenylazo) -5- in 20 minutes with stirring. hydroxy-1-naphthyl] sulfamoyl benzenesulfochloride entered. After 30 minutes, the mixture was filtered and 250 ml of water and 31 ml of concentrated hydrochloric acid were added to the solution in succession. The resulting precipitate was filtered off and washed with water. Dried in a drying cabinet.

Yield: 10.6 g Level 7: Compound No. 11

Under a nitrogen atmosphere, a filtered 85 ° C. solution of 8.9 g of dye sulfinic acid and 1 g of sodium acetate sicc were added to a solution of 4.1 g of carbinol compound from stage 5 in 250 ml of glacial acetic acid at 60-65 ° C. with stirring. placed in 200 ml of glacial acetic acid and 120 ml of water and stirred at 60-65 ° C. for 1 hour. After cooling, the resulting precipitate was filtered off and recrystallized from ethyl acetate / methanol with the addition of activated carbon.

Yield: 5.5 g

The main aspect of the present invention relates to the case where the oxidizable compound is a coloring compound and the photographically active group is a diffusing dye. For this reason, the following mainly refers to coloring compounds, but this should not be understood as a limitation. In fact, the oxidizable compounds can be used for a wide variety of other purposes, with other photographically active groups being possible. The coloring compounds according to the invention are incorporated into the casting solutions for the layers of the photographic material by one of the customary methods. The amount of coloring compound used per liter of casting solution varies within relatively wide limits, the most favorable concentration being determined on the basis of simple experiments. For example, 5-80 g, preferably 20-40 g, of coloring compound are used per liter of casting solution.

The association between diffusion-resistant coloring compound and silver halide required to achieve the desired effect can be produced, for example, by introducing the diffusion-resistant compounds from the aqueous solution into the casting solutions using existing acidic water-solubilizing groups. The non-diffusing coloring compounds can, however, also be introduced into the layers by one of the known emulsification processes. Such methods are described, for example, in British Patents 791,219 and 1,099,414 to 1,099,417. It is also possible to prepare aqueous dispersions or coloring compounds and add them to the respective casting solutions. For this purpose, aqueous slurries of the coloring compounds are finely ground, for example by intensive stirring with the addition of sharp-edged sand or by using Ulese. In a further embodiment it may be desirable, for example, to store the coloring compounds together with silver halide and, if appropriate, developer substances in the form of so-called microcapsules, two or more differently sensitized light-sensitive silver halide emulsions and the corresponding diffusion-resistant compounds in a single layer in the manner of the so-called Mixed grain emulsions are combined, as described, for example, in US Pat. No. 2,698,794. The non-diffusing coloring compounds can be accommodated in a light-sensitive layer itself or in a neighboring layer. For example, the red-sensitive layer is associated with a compound which cleaves off a cyan dye, the green-sensitive layer with a compound which cleaves off a purple dye and the blue-sensitive layer with a compound which cleaves off a yellow dye.

The term "assignment" and "assigned" is understood to mean that the mutual arrangement of silver halide emulsion and coloring compound is of such a kind that an interaction between them is possible which permits an imagewise correspondence between the silver image formed and the imagewise distribution of oxidized non-diffusing coloring compound.

• Hydrochinon
• N-Methylaminophenol
• 1-Phenyl-3-pyrazolidon
• 1-Phenyl-4,4-dimethyl-3-pyrazolidon
• 1-Phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidon 1-Phenyl-4,4-bishydroxymethyl-3-pyrazolidon
• Aminophenole
• N,N-Diethyl-p-phenylendiamin
• N-Ethyl-N-hydroxyethyl-p-phenylendiamin und 3-Methyl-N,N-diethyl-p-phenylendiamin
• N,N,N',N'-Tetraalkyl-p-phenylendiamine wie Tetramethyl-p-phenylendiamin
• Triethylsulfobutyl-p-phenylendiamin und 1,4-Bis-pyrrolidinobenzol Reduktone

In this case, the assigned coloring compound is expediently incorporated into the silver halide emulsion itself or into a layer adjacent to the silver halide emulsion layer, this adjacent layer preferably being located behind the silver halide emulsion layer (viewed in the direction of the light incident during exposure). The color-imparting compounds according to the invention are oxidized imagewise during the development of the silver image of developer oxidation products; the non-oxidized portions of the coloring compounds are then subject to a cleavage reaction under the influence of the developer or activator alkali, in which the dye residues are released in diffusing form. The usual photographic silver halide developing agents are suitable for development insofar as they are able to oxidize the color-imparting compounds according to the invention in oxidized form. Examples of suitable developers are as follows:

• Hydroquinone
• N-methylaminophenol
• 1-phenyl-3-pyrazolidone
• 1-phenyl-4,4-dimethyl-3-pyrazolidone
• 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone 1-phenyl-4,4-bishydroxymethyl-3-pyrazolidone
• Aminophenols
• N, N-diethyl-p-phenylenediamine
• N-ethyl-N-hydroxyethyl-p-phenylenediamine and 3-methyl-N, N-diethyl-p-phenylenediamine
• N, N, N ', N'-tetraalkyl-p-phenylenediamines such as tetramethyl-p-phenylenediamine
• Triethylsulfobutyl-p-phenylenediamine and 1,4-bis-pyrrolidinobenzene reductones

It should be pointed out in particular that the selection of developer substances in the process according to the invention is not limited to color developers, but that conventional black-and-white developers are preferably also used, which is to be regarded as an advantage because of the lower tendency to discoloration of the latter.

The developers can already be contained in the layers of the color photographic material, where they are activated by the alkaline activator liquid, or in the alkaline processing liquid or paste. Since the coloring compounds according to the invention themselves have developer properties, the use of auxiliary developer compounds can be dispensed with under certain conditions. In this case, the coloring compound is immediately oxidized by developable silver halide.

Since the image-wise distribution of the diffusing dye released during development coincides with the image-wise distribution of the undeveloped silver halide, it is not necessary to use direct-positive silver halide emulsions or the use of a suitable reversal process to produce positive colored transfer images, but conventional negative emulsions can be used .

The emulsions can be chemically sensitized, e.g. by adding sulfur-containing compounds during chemical ripening, for example allyl isothiocyanate, allyl thiourea, sodium thiosulfate and the like. Reducing agents, e.g. the tin compounds described in Belgian patents 493,464 and 568,687, also polyamines such as diethylenetriamine, or aminomethanesulfinic acid derivatives, e.g. according to Belgian patent 547 323 can be used.

Precious metals or noble metal compounds such as gold, platinum, palladium, iridium, ruthenium or rhodium are also suitable as chemical sensitizers. This method of chemical sensitization is described in the article by R. KOSLOWSKY, Z.Wiss.Phot. 45, 65-72 (1951).

It is also possible to sensitize the emulsions with polyalkylene oxide derivatives, e.g. with polyethylene oxide with a molecular weight between 1000 and 20,000, also with condensation products of alkylene oxides and aliphatic alcohols, glycols, cyclic dehydration products of hexitols, with alkyl-substituted phenols, aliphatic carboxylic acids, aliphatic amines, aliphatic diamines and amides. The condensation products have a molecular weight of at least 700, preferably more than 1000. To achieve special effects, these sensitizers can of course be used in combination, as described in BE-PS 537 278 and in GB-PS 727 982.

The emulsions can also be spectrally sensitized, for example by the usual mono- or polymethine dyes such as acidic or basic cyanines, hemicyanines, streptocyanm merocyanines, oxonols, hemioxonols, styryl dyes or other, also trinuclear or polynuclear methine dyes for example rhodacyanine or neocyanine. Such sensitizers are described for example in the work of FM HAMER "The Cyanine Dyes and Related Compounds" (1964) Interscience Publishers John Wiley and Sons, New Yorko

The emulsions can contain the usual stabilizers, e.g. homeopolar or salt-like compounds of mercury with aromatic or heterocyclic rings such as mercaptotriazoles, simple mercury salts, sulfonium mercury double salts and other mercury compounds. Also suitable as stabilizers are azaindenes, preferably tetra- or penta-azaindenes, in particular those which are substituted by hydroxyl or amino groups. Such compounds are described in the article by BIRR, Z.Wiss.Phot. 47, 2-27 (1952). Other suitable stabilizers include heterocyclic mercapto compounds, e.g. Phenyl mercaptotetrazole, quaternary benzothiazole derivatives, benzotriazole and the like.

Gelatin is preferably used as a binder for the photographic layers. However, this can be replaced in whole or in part by other natural or synthetic binders. On natural binders e.g. Alginic acid and its derivatives such as salts, esters or amides, cellulose derivatives such as carboxymethyl cellulose, alkyl cellulose such as hydroxyethyl cellulose, starch or their derivatives such as ethers or esters, or caragenates. Synthetic binders include polyvinyl alcohol, partially saponified polyvinyl acetate, polyvinyl pyrrolidone and the like.

The layers can be cured in the customary manner, for example using formaldehyde or halogen-substituted aldehydes which contain a carboxyl group, such as mucobromic acid, diketones, methanesulfonic acid esters, dialdehydes. To carry out the dye diffusion transfer process according to the present invention, a light-emitting element is used which contains one or more silver halide emulsion layers and the associated non-diffusing coloring compounds and an image-receiving element in which the desired color image is generated by the imagewise transferred diffusing dyes. This requires that there be firm contact between the photosensitive member and the image receiving member for at least a finite period within the development time, so that the photosensitive member as a result of the development. generated image-like distribution of diffusing dyes can be transferred to the image receiving element. The contact can be made after development has started or it can have been established before development begins. The latter is the case, for example, if a material is used to carry out the dye diffusion transfer process in which the light-sensitive element and the image-receiving element form an integral unit, also referred to below as mono-sheet material, which continues to exist even after the development process has ended, ie a separation of the photosensitive element from the image receiving element is not provided even after color transfer has taken place. Such an embodiment is described for example in DE-OS 2 019 430.

• 1) einen transparenten Schichtträger
• 2) eine Bildempfangsschicht
• 3) eine lichtundurchlässige Schicht
• 4) ein lichtempfindliches Element mit mindestens einer lichtempfindlichen Silberhalogenidemulsionsschicht und mindestens einer dieser zugeordneten nichtdiffundierenden farbgebenden Verbindung
• 5) eine Verzögerungsschicht
• 6) eine saure Polymerschicht
• 7) einen transparenten Schichtträger

A mono-plate material suitable for carrying out the dye diffusion transfer process according to the present invention has, for example, the following layer elements:

• 1) a transparent substrate
• 2) an image receiving layer
• 3) an opaque layer
• 4) a light-sensitive element with at least one light-sensitive silver halide emulsion layer and at least one non-diffusing coloring compound associated therewith
• 5) a retardation layer
• 6) an acidic polymer layer
• 7) a transparent substrate

The mono-sheet material can be composed in such a way that two different parts are produced separately from one another, namely the light-sensitive part (layer elements 1 - 4) and the cover sheet (layer elements 5 - 7), which are then placed on top of one another on the layer and connected to one another, optionally under Use of spacer strips so that a space is formed between the two parts for receiving a precisely measured amount of processing liquid. The layer elements 5 and 6, which together form the neutralization system, can also be arranged - albeit in the opposite order - between the layer support and the image-receiving layer of the light-sensitive part. Means may be provided to introduce a processing liquid between the photosensitive member and the cover sheet, e.g. in the form of a laterally arranged splitable container which pours its contents between two adjacent layers of the mono-sheet material when subjected to mechanical forces.

An essential part of the photographic material according to the present invention is the photosensitive member which is used in the case of a single dye transfer process a photosensitive silver halide emulsion layer and associated with this contains a non-diffusing coloring compound. The non-diffusing compound can be in a silver halide emulsion schioma. adjacent layer or in the silver halide emulsion layer itself, in the latter case the color of the image dye is preferably selected so that the predominant absorption range of the coloring compound does not match the predominant sensitivity range of the silver halide emulsion layer. In order to produce multicolored transfer images in true-to-life colors, however, the light-sensitive element contains three such assignments of coloring compound and light-sensitive silver halide emulsion layer, the absorption range of the coloring compound generally matching the range of spectral sensitivity of the assigned silver halide emulsion layer substantially. A prerequisite for the highest possible sensitivity is, however, that the color-providing combination is arranged in a separate binder layer (seen in the direction of the light incident during the exposure) behind the silver halide emulsion layer. The developer oxidation products formed during the development of a silver halide emulsion may of course only have an effect on the assigned coloring compound. Separating layers are therefore generally present in the photosensitive element, which effectively prevent the diffusion of the developer oxidation products into other unassigned layers.

• blauempfindliche Silberhalogenidemulsionsschicht Schicht mit nichtdiffundierender, einen diffundierenden Gelbfarbstoff freisetzender Verbindung Trennschicht
• grünsensibilisierte Silberhalogenidemulsionsschicht Schicht mitnichtdiffundierender, einen diffundierenden Purpurfarbstoff freisetzender Verbindung Trennschicht
• rotsensibilisierte Silberhalogenidemulsionsschicht Schicht mit nichtdiffundierender, einen diffundierenden Blaugrünfarbstoff freisetzender Verbindung

These separating layers can contain, for example, suitable substances which react with the developer oxidation products, for example non-diffusing hydroquinone derivatives or, if the developer is a color developer substance, non-diffusing color couplers. In a preferred embodiment, the photosensitive element therefore has the following structure (from top to bottom):

• Blue-sensitive silver halide emulsion layer. Layer with non-diffusing, separating layer that releases a diffusing yellow dye
• Green-sensitized silver halide emulsion layer. Layer with non-diffusing, separating layer that releases a diffusing purple dye
• Red-sensitized silver halide emulsion layer Layer with a non-diffusing compound that releases a diffusing cyan dye

Of course, the silver halide emulsion layers can also be arranged in a different order, but the assigned layers must also be interchanged with the coloring systems so that the assignment is retained.

The opaque layer arranged under the photosensitive element is permeable to aqueous alkaline treatment solutions and thus to the diffusing dyes. It essentially has two functions: firstly, it serves to cover the image silver remaining in the originally light-sensitive element after development, as well as the color-providing compounds remaining as color negatives, so that when viewed through the transparent substrate of the light-sensitive part, only the positive color transfer image is visible ; second, it closes the photosensitive Element from the side of the image receiving layer (downward) from light-tight. The latter is particularly important if, after exposure, the mono-sheet material is still brought into contact with the alkaline processing composition in the camera, then is to be pulled out of the camera and developed outside the camera.

Layers with sufficient opacity but sufficient permeability for diffusing dyes can be produced, for example, with suspensions of inorganic or organic dark, preferably black pigments, for example with suspensions of carbon black, in suitable binders, for example in gelatin solutions. In general, 0.5-2 _/ u thick layers containing 10-90% by weight (based on the total dry weight) of carbon black in gelatin are sufficient in order to ensure sufficient exclusion of light during development. The particle size of the pigments used is relatively uncritical as long as it does not significantly exceed 0.5 _/ u.

In addition to the black pigment layer, the opaque layer preferably also comprises a white pigment layer arranged underneath. This has the task of covering the black layer and creating a white background for the picture. All white pigments are suitable for this, provided that their opacity is sufficiently high for layers that are not too large. Examples include barium sulfate, oxides of zinc, titanium, silicon, aluminum and zircon, and also barium stearate or kaolin. Titanium dioxide is preferred as the white pigment. The same information applies to the binder, the concentration and the particle size as for the black pigments. The thickness of the white pigment layer can be varied depending on the desired whiteness of the substrate. Thicknesses between 5 and 20μ are preferably used.

Instead of the opaque layer, means for producing such an opaque layer can also be arranged in the monosheet material according to the present invention between the photosensitive element and the image-receiving layer, e.g. in the form of a laterally arranged container with a processing liquid containing an opacifying agent (pigment) which, when subjected to mechanical forces, pours its contents between the layers mentioned, so that such a pigment layer forms there.

The image-receiving layer essentially consists of a binder which contains dye mordants for fixing the diffusing dyes.

Long-chain quaternary ammonium or phosphonium compounds or ternary sulfonium compounds, e.g. those as described in US Pat. Nos. 3,271,147 and 3,271,148. Furthermore, certain metal salts and their hydroxides, which form poorly soluble compounds with the acid dyes, can also be used. The dye mordants are dispersed in the receiving layer in one of the usual hydrophilic binders, e.g. in gelatin, polyvinylpyrrolidone, wholly or partially hydrolyzed cellulose esters and the like. Of course, some binders can also act as mordants, e.g. Copolymers or polymer mixtures of vinyl alcohol and N-vinylpyrrolidone, as described, for example, in DE-AS 1 130 284, and also those which are polymers of nitrogen-containing quaternary bases, e.g. Polymers of N-methyl-2-vinylpyridine, as described, for example, in US Pat. No. 2,484,430.

At this point, reference may also be made to the crosslinking products of hydrophilic binders with quaternary polyurethanes bearing glycidyl groups described in DE-OS 2 631 521. Other usable mordants for detergents are, for example, guanyl hydrazone derivatives of acylstyrene polymers, such as, for example, described in DE-OS 2 009 498. In general, however, the latter mordants are used other binders e.g. Add gelatin.

The transparent support materials used for the monosheet material according to the invention can be the customary transparent support materials used in photographic practice, for example films of cellulose esters, polyethylene terephthalate, polycarbonate or other film-forming polymers. The alkaline processing composition sets a relatively high pH waiting (about 11 to 14) in the light-sensitive material, which triggers the development and the imagewise dye diffusion. It has been shown that at this high pH the dyes and thus the images obtained are not particularly stable. It is therefore necessary that the material is made almost neutral or slightly acidic after development is complete. This can be achieved in a known manner in that the material additionally contains an acidic polymer layer which is only gradually accessible to the alkaline processing composition in the course of development. An acidic polymer layer is understood to mean a binder layer which contains polymeric compounds with acid groups, preferably sulfo or carboxyl groups. These acidic groups react with the cations of the processing mass with salt formation and lower the pH value of the mass. Of course, the polymeric compounds and thus the acidic groups are embedded in the layer mentioned in a diffusion-resistant manner. Diverse stel len the acidic polymers are derivatives of cellulose or derivatives of polyvinyl compounds; However, there may be other polymeric compounds using findeno As usable acidic polymers may be mentioned, for example: cellulose derivatives having a free carboxyl group, for example Cellulosedicarbonsäurehalbester with a free carboxyl group such as cellulose acetate hydrogen phthalate, Celluloseacetathydrogenglutarat, Ethylcelluloseacetathydrogensuccinat, Celluloseacetathydrogensuccinathydrogenphthalat, ethers and esters of cellulose with other dicarboxylic acid anhydrides or with Sulphonic acid anhydrides, for example modified with o-sulphobenzoic anhydride, carboxymethyl cellulose, also polystyrene sulphonic acid, polyvinyl hydrogen phthalate, polyvinyl acetate hydrogen phthalate, polyacrylic acid, acetals of polyvinyl alcohol with aldehydes which are substituted by carboxy or sulpho groups, such as o-benzaldehyde or sulphonic acid, partially esterified ethylene-maleic anhydride copolymers, partially esterified methyl vinyl ether-maleic anhydride copolymers and de like.

Suitable acidic polymers are described for example in DE-OS 2 652 464.

The acidic polymer layer must contain enough acid groups to lower the pH of the processing mass from the beginning 11 to 14 to such an extent that the material is almost neutral or weakly acidic at the end (pH 5-8).

The time delay of the pE value reduction is achieved in a known manner in that the acidic polymer layer is coated with a so-called delay layer. This delay layer is an alkali-impermeable layer, which preferably consists of an alkali inert polymers, for example made of polyvinyl alcohol or a partially acetalized polyvinyl alcohol. By a suitable choice of the thickness and the composition of this delay layer, the time delay of the pH reduction can be adjusted in the desired manner. A brake layer with polymers of a novel permeability behavior is described, for example, in DE-OS 2 455 762.

Neutralization systems, which are combinations of an acidic polymer layer and a delay layer, are described, for example, in DE-FS 1 285 310. Such layer combinations can be present in the material according to the invention, for example in the light-sensitive part between the transparent layer support and the image-receiving layer.

Another possibility is to arrange the neutralization system from the acidic polymer layer and a delay layer on the cover sheet. Of course, these two layers must be arranged in such a sequence that the alkali of the processing composition must first penetrate the retardation layer in order to get into the acidic polymer layer.

The dye diffusion transfer method according to the invention can advantageously be carried out in or by means of a suitable self-developing camera. This can be provided, for example, with devices which, after exposure of the photosensitive element, make it possible to distribute a working solution between the latter and the cover sheet and to cover the photosensitive material in an opaque manner. Such a camera is preferably with two provided against each other nip rollers, between which the mono-sheet material is pulled out, the laterally arranged containers are split and release their contents between the layers of the mono-sheet material. Since the light-sensitive element is protected against unwanted exposure by opaque layers on both sides after passing through the nip rollers, the exposed material can be pulled out of the camera immediately after the development has been started.

To process the imagewise exposed monosheet material, the photosensitive element is brought into contact with the aqueous alkaline working solution. In this case, the imagewise exposed silver halide emulsion layers are developed in the presence of the developer compound, an imagewise distribution of oxidation products of the developer compound being generated in accordance with the silver image thus formed, which oxidizes the assigned coloring compound, followed by the imagewise distribution of unoxidized coloring compound under the action of the activator or developer alkali the diffusing dye is split off.

The aqueous alkaline working solution can contain viscosity-increasing additives, e.g. Hydroxyethyl cellulose. Development accelerators, stabilizers, silver salt solvents, fogging agents, antioxidants and other additives can also be contained in the working solution in a known manner.

Since the compounds according to the invention are essentially only subjected to hydrolytic cleavage in the reduced state with the release of the photographically active group, but are stable after oxidation, it is obvious to incorporate them into the layers in the oxidized form, but care must be taken must be converted into the hydrolyzable reduced form during development. This can be accomplished by the simultaneous use of so-called electron donor compounds (ED compounds), which are reducing substances which are converted into the oxidized form by reaction with developer oxidation products or with the developable silver halide and thus the reaction with the oxidized Form of the compounds of the invention are withdrawn. The ED compound remains in its active form only at those points where there is no development of silver halide, which can react with the oxidized form of the coloring compound to form the hydrolyzable reduced form, from which, under the conditions of photographic development, the diffusing dyes are released imagewise. With regard to such procedures, reference is made, for example, to DE-OS 2 809 716, which also describes a number of suitable ED compounds.

The invention has been explained above with reference to examples in which the photographically active group is a diffusing dye or diffusing dye precursor. However, other embodiments in which the photographically active group is, for example, an antifoggant, a development inhibitor, a hardening agent, a developing agent or a development accelerating agent are also appreciated. In all of these cases, the photographically active group is released imagewise, i.e. in accordance with imagewise distribution of undeveloped silver halide when using negative emulsions. This opens up a wide range of possibilities for image generation.

Embodiment 1

• Beizschicht:
• 3,75 g eines Copolymerisates aus einem Teil Styrol und einem Teil Maleinsäureimid von N,N-Dimethyl-N-hexadecyl-N-W -aminopropyl-ammoniumbromid wurden in 15 ml Ethanol gelöst und diese Lösung wurde in 75 ml 5 %iger Gelatinelösung eingerührt und homogenisiert. Nach Zusatz von 2,6 ml 5 %iger Saponinlösung und 1 ml 2 %iger wäßriger Mucochlorsäurelösung wurde auf eine übliche Gießviskosität (ca. 11 mPa.s) eingestellt und die Lösung wurde bei 40°C im Tauchverfahren auf den Träger aufgetragen (Gießgeschwindigkeit 5 m/min).

A pickling layer, a light-reflecting layer and a light-sensitive silver halide emulsion layer were applied to a transparent cellulose triacetate support in the following order:

• Pickling layer:
• 3.75 g of a copolymer of one part of styrene and one part of maleimide of N, N-dimethyl-N-hexadecyl-NW-aminopropyl-ammonium bromide were dissolved in 15 ml of ethanol and this solution was stirred into 75 ml of 5% gelatin solution and homogenized . After adding 2.6 ml of 5% saponin solution and 1 ml of 2% aqueous mucochloric acid solution, it was adjusted to a customary pouring viscosity (approx. 11 mPa.s) and the solution was applied to the support at 40 ° C. by immersion (casting speed 5 m / min).

• Eine Aufschlämmung aus 42 g Ti0₂ in 20 ml Wasser wurde unter Zusatz von 5 ml 5 %iger wäßriger Lösung von Natrium-dodecylbenzolsulfonat und 5 ml 5 %iger wäßriger Saponinlösung in 150 ml 8 %iger wäßriger Gelatinelösung dispergiert. Nach Zugabe von 1 ml 2 %iger Mucochlorsäurelösung wurde die Dispersion auf eine Viskosität von 13 mPa.s bei 40°C eingestellt und im Tauchverfahren auf die getrocknete Beizschicht aufgetragen (Gießgeschwindigkeit 5 m/min).

Light reflecting layer:

• A slurry of 42 g of Ti0 ₂ in 20 ml of water was dispersed in 150 ml of 8% aqueous gelatin solution with the addition of 5 ml of 5% aqueous solution of sodium dodecylbenzenesulfonate and 5 ml of 5% aqueous saponin solution. After adding 1 ml of 2% mucochloric acid solution, the dispersion was adjusted to a viscosity of 13 mPa.s at 40 ° C. and applied to the dried pickling layer by immersion (casting speed 5 m / min).

• Je 1 Mol der in der folgenden Tabelle aufgeführten oxidierbaren Verbindungen wurden in 3 ml Caprylsäurediethylamid und 3 ml Ethylacetat gelöst und unter Zusatz von 5 ml 5 %iger wäßriger Lösung von Natrium-dodecylbenzolsulfonat in 25 ml 5 %iger Gelatinelösung eindispergiert. Nach weiterer Zugabe von 50 ml 5 %iger Gelatine und 1 ml 2 %iger Mucochlorsäurelösung wurde jede der Dispersionen mit 18 g einer gießfertigen Silberhalogenidemulsion vermischt. Diese Silberhalogenidemulsion war hergestellt worden mit 74 g AgNO₃ pro kg Emulsion; sie hatte ein Ag/Gelatine-Verhältnis von 1:1,1 und das Halogenid war hauptsächlich Bromid mit 0,67 Mol-% Jodid. Die Mischungen wurden im Tauchverfahren mit einer Geschwindigkeit von 5 m/min bei 40°C auf die getrocknete lichtreflektierende Schicht aufgetragen.

Silver halide layer:

• 1 mol each of the oxidizable compounds listed in the following table were dissolved in 3 ml of caprylic acid diethylamide and 3 ml of ethyl acetate and dispersed in 25 ml of 5% gelatin solution with the addition of 5 ml of 5% strength aqueous solution of sodium dodecylbenzenesulfonate. After further addition of 50 ml of 5% gelatin and 1 ml of 2% mucochloric acid solution, each of the dispersions was mixed with 18 g of a ready-to-pour silver halide emulsion. This silver halide emulsion was prepared with 74 g AgNO ₃ per kg emulsion; it had an Ag / gelatin ratio of 1: 1.1 and the halide was mainly bromide with 0.67 mol% iodide. The mixtures were applied to the dried light-reflecting layer using the dipping method at a speed of 5 m / min at 40 ° C.

After drying, the various samples were exposed through a grayscale filter on the emulsion side, developed in the developer described below for 4 minutes at 18 ° C., washed and dried.

• 1,5 g Ethylendiamintetraessigsäure-Natriumsalz
• 11,5 g Borax
• 1,0 g Natriumhexametaphosphat
• 2,0 g 1-Phenyl-pyrazolidon
• 3,0 g KBr
• auffüllen mit Wasser auf 1000 ml und
• einstellen auf pH 12,5 mit 1 n NaOH

Developer:

• 1.5 g of ethylenediaminetetraacetic acid sodium salt
• 11.5 g borax
• 1.0 g sodium hexametaphosphate
• 2.0 g of 1-phenylpyrazolidone
• 3.0 g KBr
• fill up to 1000 ml with water and
• adjust to pH 12.5 with 1N NaOH

Die Tabelle enthält einen Vergleich mit entsprechenden Farbstoffen der deutschen Patentanmeldung P 28 23 159.6, die in o-Stellung zum Carbinol-Kohlenstoffatom (R⁵) ein Wasserstoffatom anstelle eines nicht deprotonierbaren Substituenten enthalten. Die Verbindungen A, B, C und D haben folgende Formeln:

Fully developed positive color wedges were obtained from each of the samples, which were visible through the transparent layer support. The color densities (D _min and Dmax) were measured behind color filters using a reflection densitometer and are summarized in the following table:

The table contains a comparison with corresponding dyes of German patent application P 28 23 159.6, which contain a hydrogen atom instead of a non-deprotonatable substituent in the o-position to the carbinol carbon atom (R ⁵ ). The compounds A, B, C and D have the following formulas:

Claims (9)

1. Photographic diffusion transfer process, in which a photographic material with at least one light-sensitive silver halide emulsion layer and an associated non-diffusing oxidizable compound which, in non-oxidized form, is subject to a cleavage reaction under the conditions of alkaline development with the release of a diffusing photographically active substance and in oxidized ⁼ form is not subject to the mentioned cleavage reaction or is subject to it only to a much lesser extent than in non-oxidized form, is exposed imagewise and is developed with a silver halide developing agent, the silver halide developing agent in oxidized form oxidizing the oxidizable compound and thereby converting it into a form which is not or only slightly cleavable by alkali, while from the pictorial distribution of non-oxidized oxidizable compound as a result of cleavage by alkali the photographically active substance is set free t is characterized in that a compound of the following formula is used as the non-diffusing oxidizable compound:

in which mean: A the rest of a photographically active group; X is a bivalent link of the formula -R- (L) _p - (R) _q -, in which R is an alkyl radical with 1-6 C atoms or an optionally substituted arylene or aralkylene radical and where the two radicals R are the same or one can have different meanings; L = -0-, -CO-, -CONR ^6- , -SO ₂ -NR ⁶ -, -O-CO-NR ⁶ - (R ⁶ = hydrogen or alkyl), -S-, -SO- or -S0 ₂ -; p = 0 or 1; q = 0 or 1; m 0 or 1; Y ¹ and Y ² (identical or different) groups or precursors of groups which, owing to their interaction with one another, can be oxidized to form a p-quinoid system; however, Y _{2 is} not a disubstituted amino group -N (R ⁸ ) ₂ ; R is an optionally substituted hydrocarbon residue; R ^{2 is} hydrogen or an optionally substituted hydrocarbon radical; R ^{3 is} a substituent as defined for R ² , a grouping which together with R ^{4 completes} a fused-on heterocyclic or carbocyclic, optionally aromatic ring, or OH, halogen, amino, Alkylamino, dialkylamino including cyclic amino groups, acylamino, alkylthio, alkoxy, aroxy or sulfo; R ^{4 is} an optionally substituted hydrocarbon radical, or a group which together with R ^{3 completes} a fused-on heterocyclic or carbocyclic, optionally aromatic ring; R ^{5 is} an optionally substituted hydrocarbon radical and wherein at least one of the substituents R ¹ , R ³ , R ^{4 contains} a diffusion-resistant radical. 2. The method according to claim 1, characterized in that A is the residue of a diffusing dye or dye precursor. 3. The method according to claim 1, characterized in that a compound of the following formula is used as the non-diffusing oxidizable compound:

in which mean: A the rest of a diffusing dye or dye precursor; X is a bivalent link; m 0 or 1; R is an optionally substituted hydrocarbon residue; _R ^{2 is} hydrogen or an optionally substituted hydrocarbon radical; R ^{3 is} a substituent as defined for R ² , a group which together with R ^{4 completes} a fused heterocyclic or carbocyclic, optionally aromatic ring, or OH, halogen, amino, alkylamino, dialkylamino including cyclic amino groups, acylamino, alkylthio, alkoxy, aroxy or sulfo; R ^{4 is} an optionally substituted hydrocarbon radical or a group which together with R ^{3 completes} a fused-on heterocyclic or carbocyclic, optionally aromatic ring; R is an optionally substituted hydrocarbon radical and at least one of the substituents R ¹ , _R ³ , _R ⁴ and R contains a diffusion-resistant radical. 4. The method according to claim 1, characterized in that in the formula of claim 1 R ^{2 is} hydrogen. ₅ . A method according to claim 1, characterized in that in the formula of claim 1 R ⁴ and R ⁵ each represent an alkyl radical. ₆ . A method according to claim 1, characterized in that in the formula of claim 1 R ^{5 is} an n-propyl radical. ₇ . Photographic recording material for the color diffusion transfer process with at least one light-sensitive silver halide emulsion layer and a non-diffusing coloring compound associated therewith, characterized in that a compound of the following formula is contained as the non-diffusing coloring compound:

in which mean: A the rest of a diffusing dye or dye product; X is a bivalent link of the formula -R- (L) _p - (R) _q -, in which R is an alkyl radical with 1-6 C atoms or an optionally substituted arylene or aralkylene radical and in which the two radicals R are the same or one different significance t _un g may have; _L = -O-, -CO-, -CONR ⁶ -, -SO ₂ -NR ⁶ -, -O-CO-NR ⁶ - ( _R ^{6 =} hydrogen or alkyl), -S-, -SO- or -SO ₂ -; p = 0 or 1; q = 0 or 1; m 0 or 1; Y ¹ and Y ² (identical or different) groups or precursors of groups which, owing to their interaction, can be oxidized to form a p-quinoid system, but Y ^{2 is} not a disubstituted amino group -N (R ⁸ ) ₂ ; R is an optionally substituted hydrocarbon. remnant of fabric; R ^{2 is} hydrogen or an optionally substituted hydrocarbon radical; R ^{3 is} a substituent as defined for R ² , a group which together with R ^{4 completes} a fused heterocyclic or carbocyclic, optionally aromatic ring, or OH, halogen, amino, alkylamino, dialkylamino including cyclic amino groups, acylamino, alkylthio, alkoxy, aroxy or sulfo; R ^{4 is} an optionally substituted hydrocarbon radical, or a group which together with R ^{3 completes} a fused-on heterocyclic or carbocyclic, optionally aromatic = ring; R ^{5 is} an optionally substituted hydrocarbon radical and at least one of the substituents R ¹ , R ³ , R ⁴ and R ^{5 contains} a diffusion-resistant radical. ₈ . Material according to claim 7, characterized in that a compound of the following formula is used as the non-diffusing oxidizable compound:

in which mean: A the rest of a diffusing dye or dye precursor; X is a bivalent link; m 0 or 1; R ^{1 is} an optionally substituted hydrocarbon residue; R ^{2 is} hydrogen or an optionally substituted hydrocarbon radical; R ^{3 is} a substituent as defined for R ² , a group which together with R ^{4 completes} a fused heterocyclic or carbocyclic, optionally aromatic ring, or OH, halogen, amino, alkylamino, dialkylamino including cyclic amino groups, acylamino, alkylthio, alkoxy, aroxy or sulfo; R ^{4 is} an optionally substituted hydrocarbon residue, or a group which together with R ^{3 completes} a fused-on heterocyclic or carbocyclic, optionally aromatic ring; R is an optionally substituted hydrocarbon radical and at least one of the substituents R ¹ , _R ³ , _R ⁴ and R ^{5 contains} a diffusion-resistant radical. G. Material according to claim 7, characterized in that in the formula of claim 1 _R ^{2 is} hydrogen.