Shifted Indophenol Dye Developers

Abstract

Dye developers and processes for making said dye developers are disclosed, along with photographic compositions and photographic elements containing said dye developers wherein the dye developer comprises a silver halide developing moiety connected to an indophenol moiety. In one aspect, the light-absorption characteristics of dye developers comprising the indophenol moiety when incorporated in a photographic element can be shifted to provide for exposure of a photosensitive material without substantial absorption competition and then can be shifted by contact with an 'onium compound to provide a good image dye. In another aspect, photographic elements are disclosed which contain a photosensitive composition having associated therewith a shifted indophenol dye developer; preferably, the photographic elements are used in image transfer film units.

Description

This invention relates to compositions of matter, processes for preparing compositions of matter, photographic elements containing these compositions of matter and processes for forming photographic image records. In one aspect, this invention relates to shifted dye developers wherein the dye is an indophenol moiety. In another aspect, this invention relates to photographic elements for recording an imagewise exposure, which elements contain shifted indophenol dye developers and to photographic image records containing a dye developer wherein the dye is an 'onium indophenoxide. In still another aspect, this invention relates to improved image transfer film units and processes for forming image records in image transfer film units.

It is known in the prior art to use dye developers in photographic elements such as image transfer systems as disclosed in U.S. Pat. Nos. 2,983,606, 3,225,001, etc., where most of the dyes of said dye developers are anthraquinone dyes or azo dyes. It is also known in the art to use shifted dye developers in image transfer systems such as disclosed in U.S. Pat. No. 3,336,287 issued Aug. 15, 1967, 3,307,947 issued Mar. 7, 1967, and the like. Several references also disclose the use of hydrolyzable groups attached to an anthraquinone or azo dye to shift the color of the dye temporarily toward lower wavelengths whereby their use in a photosensitive element will result in a reduced absorption of light available for exposure of the associated silver halide emulsion or an inner silver halide emulsion with respect to the direction of exposure -- U.S. Pat. Nos. 3,230,082 issued Jan. 18, 1966, 3,230,085 issued Jan. 18, 1966, 3,146,102 (column 12) by Weyerts et al issued Aug. 25, 1964, etc. However, improved classes of dye developers are desired which would substantially obviate the absorption competition with the associated photosensitive emulsion and underlying photosensitive emulsion layers and at the same time provide short image transfer times and good image quality in the image record after transfer.

We have now discovered a new class of compounds which can be used in photographic elements, and especially in image transfer film units, to provide improved transfer systems and improved image properties. Generally, the compounds are dye developers wherein the dye is an indophenol, referred to herein as a shifted indophenol dye developer. These compounds can be coated in the photosensitive element with low color absorption, and after exposure of the photosensitive element can be brought into contact with a positively charged compound which is preferably an 'onium compound to produce an image dye having very good image characteristics including stability, density and the like.

In one preferred embodiment, this invention relates to a photographic element comprising a support and at least one layer thereon containing a photosensitive, image-recordng material having associated therewith a dye developer of the general formula:

D--(SID)

wherein D-is an aromatic group which is a silver halide developer and (SID) is an indophenol dye moiety.

In another embodiment, this invention relates to an image transfer film unit comprising a photosensitive element containing a blue-sensitive silver halide emulsion layer having associated therewith a yellow-forming indophenol dye developer, a green-sensitive silver halide emulsion layer having associated therewith a magenta-forming indophenol dye developer, and a redsensitive silver halide emulsion having associated therewith a cyan-forming indophenol dye developer.

In another embodiment, this invention relates to a photographic film unit comprising:

1. a photosensitive element comprising a support having thereon a layer containing a silver halide composition having associated therewith a dye developer having the formula:

D-(SID)

wherein D-is an aromatic group which is a silver halide developer and (SID) is an indophenol dye moiety;

2. a dye image-receiving layer; and

3. means for discharging an alkaline processing composition within said film unit.

Preferably, the image-receiving layer comprises an 'onium compound which can be a mordant for the indophenol dye developer.

In still another embodiment, this invention relates to 'onium indophenoxides and photographic elements containing indophenoxides which have the formula:

D-(SID).sup.-.sup.+M

wherein D-is a silver halide developing group, either in the oxidized or unoxidized state, (SID) is an indophenol moiety, and M is an 'onium group.

In another highly preferred embodiment, this invention relates to image transfer elements comprising the combination of a shifted indophenol dye developer and an incorporated auxiliary silver halide developer which is a reducing agent.

In the drawings, FIG. 1 shows a representative absorption shift which is obtained with a yellow indophenol based on an open-chain ketomethylene coupler (line Y), a magenta indophenol based on a pyrazolone color coupler (line M), and a cyan indophenol based on a phenolic color coupler (line C), wherein the absorption characteristics of the indophenols as incorporated in the photographic element are shown, respectively, as lines SY, SM and SC and the absorption characteristics after contact with an 'onium compound are shown as lines Y, M and C. Further details of the absorption shift are described in Bush et al, U.S. Ser. No. 169,706 filed Aug. 6, 1971, now U.S. Pat. No. 3,791,827, which is incorporated herein by reference. FIGS. 2 and 3 show representative absorption characteristics of the dye developers of Examples 2 (Compound I) and 8 (Compound IV).

In FIGS. 4-6, a preferred film unit is described which is based on the shifted indophenol dye developers.

The shifted dye developers of this invention are generally those which comprise a silver halide developing agent moiety linked to an indophenol dye moiety. Generally, the shifted dye developers can be represented by the formula:

D-(SID)

wherein D-is a moiety of a silver halide developing agent including those having hydrolyzable groups thereon, and preferably is a disubstituted aromatic group such as a naphthalene or, more preferably, a phenylene group wherein the disubstituted groups are hydroxy groups, primary amino groups or alkylamino groups, including substituted alkylamino groups, wherein the second substituent is preferably in the ortho or para position; and (SID) is a shifted indophenol dye moiety including, of course, the desired linking groups between the dye moiety and the developing agent moiety, especially where chromophore insulating groups are desired. In one preferred embodiment, (SID) can be represented by the formula:

(COUP)=N--Ar--OH

wherein Ar is an arylene group comprising from 6 to 20 carbon atoms including substituted and unsubstituted arylene groups, fused-ring substituents and the like, and is preferably a phenylene group which is preferably substituted with halogen atoms or groups containing halogen atoms in the ortho or meta positions of the ring; and (COUP) is a color-forming coupler including the linking group to D--, such as phenolic couplers, pyrazolone couplers, pyrazolotriazole couplers, couplers having openchain methylene groups and the like, wherein said coupler is linked to said nitrogen atom through a carbon atom at the coupling position. Generally, when the above shifted dye developers are utilized in an image transfer film unit, the shifted dye developer is diffusible and will migrate to an image-receiving layer upon contact with an alkaline processing solution unless the developer group is oxidized by reaction with developable silver halide or oxidized with a redox agent; the image-receiving layer preferably has an 'onium compound associated therewith to provide the 'onium indophenoxide image dye.

The compounds or groups referred to herein as couplers contain a "coupling position" which is generally known to those skilled in the art as being the position on the coupler molecule that reacts or couples with oxidized color developing agents. Typical useful couplers include phenolic couplers, including .alpha.-naphthols which couple at the 4-position, open-chain ketomethylene couplers which couple at the carbon atom forming the methylene moiety (e.g., ##SPC1##

wherein * denotes the coupling position), 5-pyrazolone couplers which couple at the carbon atom in the 4-position, and the like. Typical specific coupler compounds which can be reacted with p-aminophenols to form the indophenol moiety according to this invention are disclosed in U.S. Pat. Nos. 2,407,210 by Weissberger et al issued Sept. 3, 1946; 2,298,443 by Weissberger issued Oct. 13, 1942; 2,875,057 by McCrossen et al issued Feb. 24, 1959; 3,265,506 by Weissberger et al issued Aug. 9, 1966; 3,408,194 by Loria Issued Oct. 29, 1968; 3,447,928 by Loria issued June 3, 1969; 2,369,489 by Porter et al issued Feb. 13, 1945; 2,600,788 by Loria et al issued June 17, 1952; 2,908,573 by Bush et al issued Oct. 13, 1959; 3,062,653 by Weissberger et al issued Nov. 6, 1962; 3,419,391 by Young issued Dec. 31, 1968; 3,519,429 by Lestina issued July 7, 1970; 3,152,896 by Tuite issued Oct. 13, 1964; 2,423,730 by Salminen et al issued July 8, 1947; 2,474,293 by Weissberger et al issued June 28, 1949; 3,476,563 by Loria issued Nov. 4, 1969; 2,772,162 by Salminen et al issued Nov. 27, 1956; and 3,002,836 by Vittum et al issued Oct. 3, 1961; and U.S. Ser. No. 778,333 by Bailey et al filed Nov. 22, 1968, now abandoned; which are all incorporated herein by reference.

The group defined as Ar above is preferably the residue of an aromatic color developing agent such as an aminophenol, a phenylenediamine and the like and, of course, including the various substituents on the aromatic group which are known in the art for the respective color developing agent. In one preferred embodiment where Ar is the nucleus of an aminophenol developing agent, the aromatic compound can contain the substituents as disclosed, for example, in Bush et al, U.S. Ser. No. 169,706 filed Aug. 6, 1971 now U.S. Pat. No. 3,791,827, which is incorporated herein by reference.

In the shifted indophenol dye developers, the indophenol moiety preferably contains an insulating linkage connecting it to the developing agent moiety (D-). Insulating linkages of this type, sometimes referred to as achromophoric groups or bonds, are known in the art, for example, as disclosed in U.S. Pat. No. 3,255,001 issued June 7, 1966. The insulating group does not contribute a color-producing group to the indophenol dye chromophore, but acts to prevent or interrupt any system of conjugation or resonance extending from the azomethine groups of the indophenol moiety to the developing group, i.e., such as a hydroquinone group. Thus, any influence of the developer group on the color characteristics of the azomethine linkage is substantially excluded. The insulating linkage which preferably forms a part of the indophenol moiety as defined herein can be any group which will break up the resonance system, for example, those groups listed in U.S. Pat. No. 3,255,001 issued June 7, 1966, and the like.

The term "azomethine linkage" as used herein is understood to mean the grouping: ##SPC2##

Preferably, the azomethine compounds of this invention are further defined as being indophenols, which is understood to refer to compounds having the general structure:

(COUP)=N--Ar--OH

wherein (COUP) is a color coupler such as a pyrazolone color coupler, a pyrazolotriazole coupler, an open-chain ketomethylene color coupler, a phenolic color coupler and the like, which is connected to the nitrogen atom in the coupling position of said coupler; and Ar is as defined above.

The term "nondiffusing" used herein has the meaning commonly applied to the term in color photography and denotes materials which for all practical purposes do not migrate or wander through organic colloid layers, such as gelatin, comprising the sensitive elements of the invention. The same meaning is to be attached to the term "immobile".

The term "diffusible" as applied to the color-providing materials of this invention has the converse meaning and denotes materials having the property of diffusing effectively through the colloid layers of the sensitive elements in the presence of the nondiffusing materials. "Mobile" has the same meaning.

The shifted indophenols are reacted with 'onium salts at appropriate times in photographic processes to provide a bathochromic absorption shift, thus forming an 'onium indophenoxide. The 'onium indophenoxides can generally be represented by the formula:

D-(SID).sup.-.sup.+M

and more preferably by:

D-(COUP)=N--Ar--O.sup.- .sup.+M

wherein D-, (SID), (COUP) and Ar are as defined above, and M is an 'onium group including sulfonium, phosphonium and, preferably, quaternary ammonium groups. When the 'onium indophenoxide is formed in or has transferred to the desired image-receiving layer, the developer group can be in the oxidized or unoxidized state.

The 'onium salts used to form the 'onium indophenoxides are generally quaternary ammonium salts, quaternary phosphonium salts, tertiary sulfonium salts and the like, and are generally used in concentrations necessary to form an 'onium indophenoxide with all of the indophenol present in the photographic element. When the 'onium compound is immobile or ballasted and present in an image layer, it is generally utilized in concentrations of about 25 mg. to about 1,000 mg. per square foot, and preferably about 50 to about 500 mg. per square foot, depending, of course, on the ratio of ' onium atoms to molecular weight of the compound employed. When the 'onium salt is supplied by a solution such as in the processing solution, typical useful concentrations range from 0.01% by weight to about 5% by weight of the 'onium compound to provide complete reaction, again depending on the concentration of the dye in the photographic element and the ratio of 'onium groups to molecular weight of the 'onium compound.

In one embodiment of this invention, color image transfer systems are prepared by using an appropriate shifted indophenol dye in each of three differently sensitized emulsion layers of a photographic element.

One layer of the element comprises a blue-sensitive silver halide emulsion which has associated therewith a shifted yellow indophenol dye developer. Typical shifted yellow dye developers have the formula:

D-(KMC)=N--Ar--OH

wherein D-and Ar are as defined above and (KMC) is an open-chain ketomethylene color coupler connected to said nitrogen atom at its coupling position. A typical specific compound of this type is:

Compound I ##SPC3##

Another layer of the element comprises a greensensitive silver halide emulsion having associated therewith a shifted magenta indophenol dye developer. Typical shifted magenta dye developers have the formula:

D-(PYZ)=N--Ar--OH

wherein D-and Ar are as defined above and PYZ is a pyrazolone or pyrazolotriazole color coupler, and preferably a color coupler which contains either the moieties: ##SPC4##

or ##SPC5##

wherein the 4-position in said ring is directly bonded to the nitrogen atom in the above dye developer formula. Typical specific compounds of this type are:

Compound II ##SPC6##

and

Compound V ##SPC7##

Another layer of the element comprises a red-sensitive silver halide emulsion having associated therewith a shifted cyan indophenol dye developer. Typical shifted cyan dye developers have the formula:

D-(PhC)=N--Ar--OH

wherein D--and Ar are as defined above and PhC is a phenolic color coupler connected to said nitrogen atom at its coupling position. Typical specific compounds of this type are:

Compound III ##SPC8##

and ##SPC9##

Compound IV

The shifted indophenol dye developers can be prepared by several techniques. In one embodiment, oxichromic developers are prepared as described in Lestina and Bush, U.S. Ser. No. 206,949 entitled "Oxichromic Compounds, Stabilized Oxichromic Compounds and Processes for Preparing Same" filed Dec. 10, 1971, and the oxichromic developers are then chromogenically oxidized by aerial oxidation, electrochemical oxidation and the like to provide indophenol dye developers. In another embodiment, the indophenol dye developers are prepared by 1) reacting a masked silver halide developing compound with a color coupler by a condensation reaction, 2) reacting the condensation product with an aminophenol and 3) then removing the masking groups from the moiety which was the silver halide developing compound. In certain variations, the aminophenol can be reacted with the color coupler before condensation with the masked silver halide developing compound. The color coupler can be reacted with an oxidized aminophenol to form the dye or, in certain embodiments, the couplers when halogenated on the active methylene group can be reacted with unoxidized aminophenols, as disclosed in U.S. Ser. Nos. 206,924 by Machiele or 206,927, now abandoned, by Reardon, both filed Dec. 10, 1971.

Generally, it is known in the prior art to make dye developers by reacting a masked developer with a dye moiety by a condensation reaction, for example, as disclosed in Journal of Chemical and Engineering Data, Vol. 9, No. 2, 1964, pp. 232-238. After condensation, the masking groups protecting the silver halide developing functions can be readily removed since dyes used in the past, such as azo dyes, anthraquinone dyes and the like, are relatively stable to conditions necessary to remove the masking groups. In one embodiment, we have now found that dye developers comprising dye moieties containing an azomethine linkage, such as indophenol dyes, can be prepared by condensation reactions with masked developers when precautions are taken to use mild hydrolysis conditions wherein the pH is maintained between pH of about 7 to about 10 and the masking groups are groups which will readily hydrolyze under these conditions such as, for example, masking groups forming carbonates, oxalates, trifluoroacetates and the like with the silver halide developing moiety. When masking groups such as acetoxy groups are used on the silver halide developing moiety, hydrolysis of the masking group is generally accompanied by substantial destruction of the indophenol.

The hydrolysis reaction is preferably carried out with a mild hydrolyzing agent such as weak alkali, methylamine, thiourea, zinc and acetic acid and the like. Generally, the hydrolysis procedure is dependent on the groups on the dye moiety and the specific group to be removed. However, the above hydrolyzing agents can generally be used to achieve removal of carbonate, oxalate, trifluoroacetate groups and the like.

In certain preparations of the dye developers of this invention, the masking groups are attached to a developing moiety which is preferably a polyhydroxybenzene compound such as hydroquinone, and the masking groups are carbonate-containing masking groups such as carboalkoxy groups, carbobenzoxy groups and the like which can contain from 2-20 carbon atoms.

The shifted indophenol dye developers are especially useful in image transfer systems since they can be incorporated in the silver halide image-recording layer without substantial detrimental adsorption of light in any of the recording layers, i.e., the yellow, green and red recording layers, During development, the indophenol dye developers are insolubilized in those areas where silver halide development occurs and the unreacted indophenol dye developer is free to diffuse or migrate to a receiver layer such as a mordant layer. At some point after imagewise exposure of the silver halide layer, the indophenol dye developer can be contacted with an 'onium compound to convert the indophenol moiety to an 'onium indophenoxide which will provide a desired shift in color adsorption providing highly useful dyes for color systems.

A particularly preferred embodiment of the present invention involves a photographic film unit comprising:

1. a photosensitive element comprising a support having thereon a silver halide emulsion layer having associated therewith an indophenol dye developer,

2. a dye image-receiving layer having associated therewith an 'onium compound, and

3. a container means for discharging an alkaline processing composition within said unit. Preferably, said container means is a rupturable container which is positioned during processing of said film unit so that a compressive force applied to the container by pressure-applying members will effect a discharge of the container's contents into the film unit.

The dye image-receiving layer of the film unit can be located on a separate support adapted to be superposed on the photosensitive element after exposure thereof. Such image-receiving elements are disclosed, for example, in U.S. Pat. No. 3,362,819. The rupturable container is usually positioned during processing of said film unit so that a compressive force applied to the container by pressure-applying members in a camera will effect a discharge of the container's contents between the image-receiving element and the outermost layer of the photosensitive element. The dye image-receiving layer can also be located integral with the photosensitive element between the support and the lowermost photosensitive silver halide emulsion layer. Such integral receiver-negative photosensitive elements are disclosed, for example, in U.S. Pat. No. 3,415,644 and are useful in camera apparatus of the type disclosed in Belgian pat. Nos. 718,553 and 718,554. The processing composition for such integral elements wherein the receiver is permanently laminated to the negative contains opacifying agents such as titanium dioxide or carbon black. Barrier layers such as those described in subsequent paragraphs may be used to advantage in such integral elements between the various emulsion and dye-developer layers.

In one highly preferred embodiment according to this invention, which is shown in FIG. 5 in detail, the shifted indophenol dye developers are used in an integral image transfer system wherein the image-receiving layer is separated from the image-recording layers, i.e., photosensitive layers containing silver halide emulsions, by a processing composition and dye developer-permeable opaque layer. The image-recording silver halide emulsions have associated therewith respectively a dye image-providing material which is a dye developer. The processing composition is uniformly applied to the image-recording layers on the side opposite the opaque layer, which can be accomplished by inserting an alkaline composition between the image-recording layers and a cover sheet. The processing composition permeates the image-recording layers, rendering the dye developer nondiffusible in the developed areas, and initiates diffusion in the nondeveloped areas wherein the dye developer can diffuse through the opaque layer to the image-receiving layer and upon treatment with an 'onium compound will provide the desired image dye. Since the element cannot be exposed through the opaque layer, it must, of course, be exposed from the opposite side. In this system, the present shifted indophenol developers permit exposure through the required side and still obtain effective contact with the silver halide emulsion to render the dye developer nondiffusing in the developed areas, thus avoiding severe color contamination; since the shifted indophenol dye developers can be incorporated in the emulsion layer or positioned between the emulsion layer and the exposure source without substantial competitive light absorption, a high-speed photographic system with this format based on negative emulsions and diffusible dye image-providing substances can now be made. In highly preferred embodiments, image transfer elements of this type are made with a support having an image-receiving layer thereon and in sequence an opaque layer and at least one image-recording layer with a cover sheet superposed on the image-recording layer to permit uniform application of a processing liquid to the side of the image-recording layer opposite the opaque layer. After processing, the cover sheet can remain laminated with the support having said layers coated thereon.

The color film assembly of the present invention may contain various silver halide emulsion layers disposed in the usual order, i.e., the blue-sensitive silver halide emulsion layer first with respect to the exposure side, followed by the green-sensitive and red-sensitive silver halide emulsion layers. If desired, a yellow dye layer of a Carey Lea silver layer may be present between the blue-sensitive and green-sensitive silver halide emulsion layer for absorbing or filtering blue radiation that may be transmitted through the blue-sensitive layer. If desired, the selectively sensitized silver halide emulsion layers may be disposed in a different order, e.g., the red-sensitive layer first with respect to the exposure side, followed by the green-sensitive and blue-sensitive layers, since many of the dye developers of this invention which are in association with the sensitive layers do not absorb substantial radiation in the visible region of the radiation spectrum.

Our novel indophenol dye developers may be employed for all colors or in combination with suitable additional dye developers in a three-color photosensitive element of the invention. Dye developers, i.e., compounds which contain in the same molecule both the chromophoric system of a dye and also a silver halide developing function, and their functioning in color diffusion transfer systems in general are well-known in the art as shown, for example, by U.S. Pat. Nos. 2,983,606, 2,992,106, 3,047,386, 3,076,808, 3,076,820, 3,077,402, 3,126,280, 3,131,061, 3,134,762, 3,134,765, 3,135,604, 3,135,605, 3,135,606, 3,135,734, 3,141,772, 3,142,565, 3,362,819, 3,415,644, 3,415,645, 3,415,646, and the like.

The shifted dye developers having the formula:

D-(SID)

as defined above, are useful in photographic systems and especially in image transfer systems. The shifted dye developers of this type are generally diffusible in an alkaline medium. In image transfer systems, the shifted dye developer is associated with a silver halide emulsion wherein the silver halide emulsion is exposed and then treated with an alkaline processing solution which permeates the layers containing the silver halide emulsion and the shifted dye developer to develop the exposed silver halide. In the areas where the silver halide emulsion is developed, the shifted dye developer is rendered relatively nondiffusing compared with the remainder of the shifted dye developer which can diffuse imagewise to an image-receiving layer wherein it can be mordanted. Upon contact with an 'onium salt, which is preferably carried out near or in the image-receiving layer, the 'onium indophenoxide image dye is formed.

The developing group D in the above dye developers is generally responsible for changes in diffusibility of the shifted dye developer and, upon oxidation by reaction with exposed silver halide or an auxiliary developer, it is preferably oxidized to a relatively immobile form. In highly preferred embodiments, the group defined as D is a polyhydroxy-substituted aromatic silver halide developing function, and preferably a hydroquinone.

Black-and-white or one-color systems can be made which employ as few as one silver halide emulsion and a shifted dye developer selection which will provide the desired net color effect. Subtractive multicolor systems can also be made such as, for example, three-color systems described in detail above wherein a blue-sensitive emulsion has associated therewith a shifted yellow indophenol dye developer, a green-sensitive emulsion has associated therwith a shifted magenta indophenol dye developer, and a red-sensitive emulsion has associated therewith a shifted cyan indophenol developer.

Generally, the shifted indophenol dye developers referred to above can be incorporated in the photographic elements in sufficient quantities to provide the desired image dye density after processing as known in the art for dye image-providing materials. The concentrations will vary, of course, depending on the type of compound employed, the film unit structure and the like.

In accordance with this invention when indophenols are formed in the process, they are preferably contacted with 'onium compounds to form 'onium indophenoxides. The 'onium compounds can either be soluble compounds which can be added by contacting the indophenol with a solution of the 'onium compound or can be high-molecular-weight compounds which are relatively insoluble in water and can be placed in at least one layer of the photographic element, such as in the mordant layer where the indophenol produces the 'onium indophenoxide image dye.

In one embodiment, especially useful dye images have been obtained through the combination of indophenols and quaternary ammonium compounds. As is known, quaternary ammonium compounds are organic compounds containing a nitrogen atom having a net positive charge. Generally, they can be considered as derivatives of ammonium compounds wherein the four valences usually occupied by the hydrogen atoms are occupied by organic radicals. Generally, the organic radicals are joined directly to the nitrogen through a single or double carbon-to-nitrogen bond. The term "quaternary ammonium," as used herein, is intended to cover compounds wherein said nitrogen is one of the nuclear atoms in a heterocyclic ring, as well as those wherein each of the four valances is attached to separate organic radicals, e.g., tetraalkyl quaternary ammonium compounds. As illustrations of quaternary ammonium compounds, mention may be made of those represented by the following formulae: ##SPC10##

wherein each R is an organic radical; Y is an anion, e.g., hydroxy, bromide, chloride, toluenesulfonate, etc.; and Z represents the atoms necessary to complete a heterocyclic ring. As examples of compounds within Formulae 1, 2 and 3, mention may be made of tetraethylammonium bromide, N-ethylpyridinium bromide, N,N-diethylpiperidinium bromide, ethylene-bis-pyridinium bromide, 1-ethylpyridinium bromide, 1-phenethyl-3-picolinium bromide, tetraalkylammonium salts, cetyltrimethylammonium bromide, polyalkylene oxide bis-quaternary ammonium salts such as polyethylene oxide bis-pyridinium perchlorate, the heterocyclic quaternary ammonium salts mentioned which form the methylene bases including 3-methyl-2-ethylisoquinolinium bromide, 3-methylisoquinolinium methyl-p-toluenesulfonate, 1-ethyl-2-methyl-3-phenethylbenzimidazolilum bromide, 5,6-dichloro-1-ethyl-2-methyl-3-(3-sulfobutyl)benzimidazolium betaine and the pyridinium salts below.

Other useful 'onium compounds include tertiary sulfonium and quaternary phosphonium compounds which are represented by the formulae:

(R).sub. 3 2.sup.+ X.sup.- TM(4)

and

(R)4P.sup.+ X.sup.- TM(5)

wherein each R is an organic radical, e.g., alkyl, aralkyl, aryl, etc., groups; and X is an anion, e.g., hydroxy, bromide, chloride, toleuenesulfonate, etc. As examples of tertiary sulfonium and quaternary phosphonium compounds, mention may be made of lauryldimethylsulfonium p-toluenesulfonate, nonyldimethylsulfonium p-toluenesulfonate and octyldimethylsulfonium p-toluenesulfonate, butyldimethylsulfonium bromide, triethylsulfonium bromide, tetraethylphosphonium bromide, dimethylsulfonium p-toluenesulfonate, dodecyldimethylsulfonium p-toluenesulfonate, decyldimethylsulfonium p-toluenesulfonate and ethylene-bis-oxymethyltriethylphosphonium bromide.

The 'onium compounds may be used as the hydroxide or as the salt. When the 'onium compounds are used as the salt, the anion may be a derivative of any acid. However, it should be noted that when the anion is iodide, such iodide may have deleterious effects on the emulsion and suitable precautions should be taken if it is to be in contact with the emulsion before development is complete. Especially good results are obtained when the 'onium compounds employed are bromides.

Useful heterocyclic quaternary ammonium compounds which form the methylene bases diffusible in alkaline solution have the general formulas:

1-.gamma.-phenylpropyl-2-picolinium bromide

2,4-dimethyl-1-phenethylpyridinium bromide

2,6-dimethyl-1-phenethylpyridinium bromide

5-ethyl-2-methyl-1-phenethylpyridinium bromide

2-ethyl-1-phenethylpyridinium bromide

1-[3-(N-pyridinium bromide)propyl]-2-picolinium p-toluenesulfonate ##SPC11##

anhydro-1-(4-sulfobutyl)-2-picolinium hydroxide ##SPC12##

.alpha.-picoline-.beta.-naphthoylmethyl bromide ##SPC13##

1-.beta.-phenylcarbamoyloxyethyl-2-picolinium bromide ##SPC14##

1-methyl-2-picolinium p-toluenesulfonate

1-phenethyl-2,4,6-trimethylpyridinium bromide

1-phenethyl-4-n-propylpyridinium bromide

4 -.gamma.-hydroxypropyl-1-phenethylpyridinium bromide and

1-n-heptyl-2-picolinium bromide

In highly preferred embodiments of the invention, the image dye is mordanted in a polymeric material such as a polymer with 'onium groups thereon. Typical useful mordants of this type are vinylpyridinium compounds of the type disclosed in U.S. Pat. No. 2,484,430 issued Nov. 10, 1949; polymers containing quaternary ammonium groups such as disclosed in U.S. Ser. Nos. 734,873 by Cohen et al filed June 6, 1968, now U.S. Pat. No. 3,625,694, 100,487 by Cohen et al filed Dec. 21, 1970, now U.S. Pat. No. 3,758,445, 100,491 by Cohen et al filed Dec. 21, 1979, now U.S. Pat. No. 3,709,690, 709,793 by Cohen et al filed Mar. 1, 1968, now U.S. Pat. No. 3,639,357, and U.S. Pat. Nos. 3,488,706 by Cohen et al issued Jan. 6, 1970, and 3,557,006 by Cohen et al issued Jan. 19, 1970; and the like.

In another preferred embodiment, the mordant is an 'onium coacervate mordant such as disclosed in Bush, U.S. Pat. No 3,271,147 issued Sept. 6, 1966.

In FIGS. 4-6, a preferred film unit of the invention is described with the various elements magnified for purposes of illustration only wherein like numbers appearing in the various figures refer to like components.

In FIG. 4, rupturable container 11 is positioned transverse a leading edge of the photosensitive laminate and is held in place by binding means 30, which can be a pressure-sensitive tape or the like which encloses that edge of the laminate. The other edges of the photosensitive laminate are sealed together, either directly or with a spacer member, to prevent leakage of processing solution during and after photographic processing when rupturable container 11 is broken open by pressure-applying members 36 to discharge its contents into the photosensitive laminate.

In FIG. 5, film unit 10 comprises rupturable container 11 containing, prior to passing between pressure-applying members 36, an alkaline processing composition 12 containing an opacifying agent and a photosensitive laminate comprising top transparent sheet 25 coated with polymeric acid layer 24 and polymeric timing layer 23 and a photosensitive element comprising a transparent support layer 15 coated with an image receiving layer 16 associated with an 'onium compound, an opaque reflecting layer 17, a red-sensitive silver halide emulsion layer 18 associated with a cyan dye image-providing material, barrier interlayer 19, a green-sensitive silver halide emulsion layer 20 associated with a magenta dye image-providing material, barrier interlayer 21, and a blue-sensitive silver halide emulsion layer 22 associated with a yellow dye image-providing material. Exposure of the film unit takes place through the top transparent sheet 25 which is preferably an actinic radiation transmissive flexible sheet material.

In FIG. 6, film unit 10 has been passed between pressure-applying members 36 such as would be found in a camera, thus causing rupturable container 11 to collapse and discharge the alkaline processing composition 12 containing an opacifying agent between the polymeric timing layer 23 and the blue sensitive silver halide emulsion layer 22. After development and image transfer has taken place, a positive, right-reading image may be viewed through transparent support 15.

The structural integrity of the photosensitive laminate can be maintained, at least in part, by the adhesive characteristics between the various layers of the laminate. However, the adhesion exhibited at the interface between the polymeric timing layer 23 of top transparent sheet 25 and underlying layer 22 is less than the adhesion at the remaining interfaces of the laminate in order to facilitate distribution of processing composition 12 between these two layers.

The film unit of our invention may be constructed by assembling the various parts in an atmosphere maintained at a pressure lower than atmospheric pressure and by sealing the transparent sheet to the photosensitive element along their edges in order to prevent the admission of air between them. The exclusion of air between the transparent sheet and the photosensitive element is desirable in order to prevent air bubbles from being entrained in the processing composition which would form discontinuities in the positive image. Details of this method of assembly and other methods for assuring a uniform distribution of processing composition between two sheets are described in Belgian Pat. No. 711,897.

The film unit of our invention can also contain a liquid trap at the opposite end from which processing composition is introduced in order to trap any excess processing composition and keep it from being expelled from the film unit. The liquid trap may also function to let air escape, if any is present. Such liquid traps are disclosed, for example, in Belgian Pat. No. 711,899.

The film unit of our invention may also be processed in the manner described in Belgian Pat No. 711,898 wherein two sets of pressure rollers are used in order to expel any air between the transparent sheet and the photosensitive element and also to facilitate an even distribution of processing composition between said sheet and element. The transparent sheet in our film unit may also be fluted along the length of the side edges, similar to the technique described in Belgian Pat. No. 711,898, in order to assist in distributing the processing composition evenly between the transparent sheet and the photosensitive element.

If it is desired to have residual water in the film unit leave the system after processing, this may be accomplished by incorporating into the film unit a desiccating layer to absorb water or by providing access to the atmosphere in order to let the water evaporate, e.g., by employing a water-permeable transparent sheet or a water-permeable film support for the photosensitive element or by allowing water to evaporate through the liquid traps in the film unit as described above, etc.

Rupturable container 11 can be of the type disclosed in U.S. Pat. Nos. 2,543,181, 2,634,886, 2,653,732, 2,723,051, 3,056,492, 3,056,491 and 3,152,515. In general, such containers comprise a rectangular sheet of fluid- and air-impervious material folded longitudinally upon itself to form two walls which are sealed to one another along their longitudinal and end margins to form a cavity in which processing composition 12 containing an opacifying agent is contained (see FIG. 5). The longitudinal marginal seal 35 is made weaker than the end margin seals so as to become unsealed in response to the hydraulic pressure generated within the fluid contents 12 of the container by the application of a compressive force to the outside walls of the container.

As illustrated in FIGS. 4 and 5, container 11 is fixedly positioned and extends transverse a leading edge of the photosensitive laminate so that a compressive force applied to said container will effect a unidirectional discharge of the container's contents between the polymeric timing layer 23 of top transparent sheet 25 and underlying layer 22. In FIG. 5, the weak longitudinal marginal seal 35 is directed toward the interface between layers 22 and 23 to facilitate this operation.

In the performance of a multicolor diffusion transfer process employing film unit 10, the unit is exposed to radiation incident on the photosensitive laminate's upper surface through transparent sheet 25, as illustrated in FIG. 5. Subsequent to exposure, the film unit 10 is processed by passing it between pressure-applying members 36 in order to apply compressive pressure to frangible container 11 and to effect rupture of longitudinal seal 35 and distribution of alkaline processing composition 12 containing an opacifying agent between layers 23 and 24 of film unit 10. The alkaline processing composition permeates the silver halide emulsion layers 22, 20 and 18 to initiate imagewise development of the silver halide. Diffusible yellow, magenta and cyan dye image-providing materials are formed from material associated with the silver halide emulsions in layers 22, 20 and 18 as a function of the imagewise exposure of their associated emulsions. At least part of the imagewise distributions of mobile yellow-, magenta- and cyan-forming materials transfer, by diffusion, to the image-receiving layer 16 to provide a positive dye image therein, preferably upon contact with an 'onium compound. This positive, right-reading image can then be viewed through transparent support layer 15 on the opaque reflecting layer 17 background. Since the receiving layer does not have to be stripped away from the negative portion of the film unit, the composite structure can be maintained intact subsequent to said processing.

In accordance with the invention, shifted dye developers permit exposure through the required side and still retain effective contact with the silver halide emulsion to render the dye image-providing material nondiffusing in the developed areas, thus avoiding severe color contamination. The shifted dye developers can generally be incorporated in the emulsion layer or positioned between the emulsion layer and the exposure source without substantial competitive light absorption, so that a high-speed photographic system with this format based on negative emulsions and diffusible dye image-providing substances can now be made.

In a color film unit according to the invention, each silver halide emulsion layer containing a dye image-providing material or having the dye image-providing material present in a contiguous layer may be separated from the other silver halide emulsion layers in the negative portion of the film unit by materials in addition to those described above, including gelatin, calcium alginate, or any of those disclosed in U.S. Pat. No. 3,384,483, polymeric materials such as polyvinylamides as disclosed in U.S. Pat. No. 3,421,892, or any of those disclosed in French Pat. No. 2,028,236 or U.S. Pat. Nos. 2,992,104, 3,043,692, 3,044,873, 3,061,428, 3,069,263, 3,069,264, 3,121,011 and 3,427,158.

Generally, except where noted otherwise, the silver halide emulsion layers in the invention comprise photosensitive silver halide dispersed in gelatin and are about 0.6 to 6 microns in thickness; the dye image-providing materials are dispersed in an aqueous alkaline solution-permeable polymeric binder, such as gelatin, as a separate layer about 1 to 7 microns in thickness; and the alkaline solution-permeable polymeric interlayers, e.g., gelatin, are about 1 to 5 microns in thickness. Of course, these thicknesses are approximate only and can be modified according to the product desired. In addition to gelatin, other suitable hydrophilic materials include both naturally occurring substances such as proteins, cellulose derivatives, polysaccharides such as dextran, gum arabic and the like; and synthetic polymeric substances such as water-soluble polyvinyl compounds like poly(vinylpyrrolidone), acrylamide polymers and the like.

The photographic emulsion layers and other layers of a photographic element employed in the practice of this invention can also contain, alone or in combination with hydrophilic, water-permeable colloids, other synthetic polymeric compounds such as dispersed vinyl compounds such as in latex form, and particularly those which increase the dimensional stability of the photographic materials. Suitable synthetic polymers include those described, for example, in U.S. Pat. Nos. 3,142,568 by Nottorf issued July 28, 1964, 3,193,386 by White issued July 6, 1965, 3,062,674 by Houck et al issued Nov. 6, 1962, 3,220,844 by Houck et al issued Nov. 30, 1965, 3,287,289 by Ream et al issued Nov. 22, 1966, and 3,411,911 by Dykstra issued Nov. 19, 1968. Particularly effective are waterinsoluble polymers of alkyl acrylates and methacrylates, acrylic acid, sulfoalkyl acrylates or methacrylates, those which have cross-linking sites which facilitate hardening or curing, and those having recurring sulfobetaine units as described in Dykstra, Canadian Pat. No. 774,054.

Any material can be employed as the image-receiving layer in this invention as long as the desired function of mordanting or otherwise fixing the dye images will be obtained. The particular material chosen will, of course, depend upon the dye image to be mordanted as mentioned hereinbefore. In one embodiment, the photographic elements of this invention contain an image-receiving layer which comprises a polyvinylpyridine mordant. However, the dyes formed with the polyvinylpyridine mordant appear to be distinguished from those formed with an 'onium mordant in that they can be removed from the mordant layer by repeated washings.

Use of a pH-lowering layer in the film unit of the invention will usually increase the stability of the transferred image. Generally, the pH-lowering layer will effect a reduction in the pH of the image layer from about 13 and 14 to at least 11 and preferably 5-8 within a short time after imbibition. For example, polymeric acids as disclosed in U.S. Pat. No. 3,362,819 may be employed. Such polymeric acids reduce the pH of the film unit after development to terminate development and substantially reduce further dye transfer and thus stabilize the dye image. Such polymeric acids comprise polymers containing acid groups, such as carboxylic acid and sulfonic acid groups, which are capable of forming salts with alkali metals, such as sodium or potassium, or with organic bases, particularly quaternary ammonium bases, such as tetramethyl ammonium hydroxide. The polymers can also contain potentially acid-yielding groups such as anhydrides or lactones or other groups which are capable of reacting with bases to capture and retain them. Generally, the most useful polymeric acids contain free carboxyl groups, being insoluble in water in the free acid form and which form watersoluble sodium and/or potassium salts. Examples of such polymeric acids include dibasic acid half-ester derivatives of cellulose, which derivatives contain free carboxyl groups, e.g., cellulose acetate hydrogen phthalate, cellulose acetate hydrogen glutarate, cellulose acetate hydrogen succinate, ethyl cellulose hydrogen succinate, ethyl cellulose acetate hydrogen succinate, cellulose acetate succinate hydrogen phthalate; ether and ester derivatives of cellulose modified with sulfoanhydrides, e.g., with ortho-sulfobenzoic anhydride; polystyrene sulfonic acid; carboxymethyl cellulose; polyvinyl hydrogen phthalate; polyvinyl acetate hydrogen phthalate; polyacrylic acid, acetals of polyvinyl alcohol with carboxy or sulfo-substituted aldehydes, e.g., o-, m- or p-benzaldehyde sulfonic acid or carboxylic acid; partial esters of ethylene/maleic anhydride copolymers; partial esters of methylvinyl ether/maleic anhydride copolymers; etc. In addition, solid monomeric acid materials could also be used such as palmitic acid, oxalic acid, sebacic acid, hydrocinnamic acid, metanilic acid, paratoluenesulfonic acid and benzenedisulfonic acid. Other suitable materials are disclosed in U.S. Pat. Nos. 3,422,075 and 2,635,048.

The pH-lowering layer is usually about 0.3 to about 1.5 mils in thickness and can be located in the receiver portion of the film unit between the support and the image-receiving layer, on the cover sheet, or it can be located anywhere within the film unit as long as the desired function is obtained.

An inert timing or spacer layer coated over the pH-lowering layer may also be used to "time" or control the pH reduction of the film unit as a function of the rate at which the alkali diffuses through the inert spacer layer. This timing layer can also be used effectively to isolate oxidizing materials in a layer adjacent the image-receiving layer wherein oxidant will be released after alkali breakdown of the timing layer. Examples of such timing layers include gelatin, polyvinyl alcohol or any of those disclosed in U.S. Pat. No. 3,455,686. The timing layer is also effective in evening out the various reaction rates over a wide range of temperatures, e.g., premature pH reduction is prevented when imbibition is effected at temperatures above room temperature, for example, at 95.degree. to 100.degree. F. The timing layer is usually about 0.1 to about 0.7 mil in thickness. Especially good results are obtained when the timing layer comprises a hydrolyzable polymer or a mixture of such polymers which are slowly hydrolyzed by the processing composition. Examples of such hydrolyzable polymers include polyvinly acetate, polyamides, cellulose esters, etc.

The alkaline processing composition employed in this invention is the conventional aqueous solution of an alkaline material, e.g., sodium hydroxide, sodium carbonate or an amine such as diethylamine, preferably possessing a pH in excess of 12, and preferably containing an auxiliary developing agent. The solution also preferably contains a viscosity-increasing compound such as a high-molecular-weight polymer, e.g., a water-soluble ether inert to alkaline solutions such as hydroxyethyl cellulose or alkali metal salts of carboxymethyl cellulose such as sodium carboxymethyl cellulose. A concentration of viscosity-increasing compound of about 1 to about 5% by weight of the processing solution is preferred which will impart thereto a viscosity of about 100 cps. to about 200,000 cps. If desired, an adhesive may be added to the processing composition to increase further the adhesion of the transparent sheet to the photosensitive element after processing.

The alkaline processing composition employed in this invention can also contain an auxiliary or accelerating developing agent which does not contain the structure D-(SID) as defined above. Typical useful auxiliary developing agents (reducing agents) are p-methylaminophenol, 2,4-diaminophenol, p-benzylaminophenol, hydrozuinone, toluhydroquinone, phenylhydroquinone, 4-methylphenylhydroquinone, etc. A plurality of auxiliary or accelerating developing agents such as those disclosed in U.S. Pat. No. 3,039,869 can also be employed. Such auxiliary or accelerating developing agents can be employed in the liquid processing composition or may be contained, at least in part, in any layer or layers of the film unit such as the silver halide emulsion layers, the dye image-providing material layers, interlayers, image-receiving layer, etc., and are preferably coated in the layers of the photosensitive element.

The alkaline processing composition employed in this invention can also contain a desensitizing agent such as methylene blue, nitro-substituted heterocyclic compounds, 4,4'-bipyridinium salts, etc., to insure that the photosensitive element is not further exposed after it is removed from the camera for processing.

While the alkaline processing composition used in this invention can be employed in a rupturable container, as described previously, to facilitate conveniently the introduction of processing composition into the film unit between the transparent sheet and the photosensitive element, other means of discharging processing composition within the film unit could also be employed, e.g., interjecting processing solution with communicating members similar to hypodermic syringes which are attached either to a camera or camera cartridge, as described in Harvey, U.S. Pat. No. 3,352,674 issued November 14, 1967.

Any opacifying agent can be employed in the processing composition in certain embodiments of our invention. Examples of opacifying agents include carbon black, barium sulfate, zinc oxide, barium stearate, silver flake, silicates, alumina, zirconium oxide, zirconium acetyl acetate, sodium zirconium sulfate, kaolin, mica, titanium dioxide, organic dyes such as the nigrosines, or mixtures thereof in widely varying amounts depending upon the degree of opacity desired. In general, the concentration of opacifying agent should be sufficient to prevent further exposure of the film unit's silver halide emulsion or emulsions by ambient actinic radiation transversing through the top transparent sheet subsequent to distribution of the processing solution between the top transparent sheet and the underlying layer adjacent thereto. For example, carbon black or titanium dioxide will generally provide sufficient opacity when they are present in the processing solution in an amount of from about 5 to 40% by weight. After the processing solution and opacifying agent have been distributed into the film unit, processing may take place out of the camera in the presence of actinic radiation in view of the fact that the silver halide emulsion or emulsions of the laminate are appropriately protected by incident radiation, at one major surface by the opaque processing composition and at the remaining major surface by the alkaline solution-permeable opaque layer. Opaque binding tapes can also be used to prevent edge leakage of actinic radiation incident on the silver halide emulsion.

When titanium dioxide or other white pigments are employed as the opacifying agent in the processing composition in our invention, it may also be desirable to employ in cooperative relationship therewith a pH-sensitive opacifying dye such as a phthalein dye. Such dyes are light-absorbing or colored at the pH at which image formation is effected and colorless or not light-absorbing at a lower pH. Other details concerning these opacifying dyes are described in French Pat. No. 2,026,927.

The alkaline solution-permeable, susbstantially opaque, light-reflective layer in the photographic film unit of our invention can generally comprise any opacifier dispersed in a binder as long as it has the desired properties. Particularly desirable are white light-refelective layers since they would be esthetically pleasing backgrounds on which to view a transferred dye image and would also possess the optical properties desired for reflection of incident radiation. Suitable opacifying agents include titanium dioxide, barium sulfate, zinc oxide, barium stearate, silver flake, silicates, alumina, zirconium oxide, zirconium acetyl acetate, sodium zirconium sulfate, kaolin, mica, or mixtures thereof in widely varying amounts depending upon the degree of opacity desired. The opacifying agents may be dispersed in any binder such as an alkaline solution-permeable polymeric matrix such as, for example, gelatin, polyvinyl alcohol, and the like. Brightening agents such as the stilbenes, coumarins, triazines and oxazoles can also be added to the light-reflective layer, if desired. When it is desired to increase the opacifying capacity of the light-reflective layer, dark-colored opacifying agents may be added to it, e.g., carbon black, nigrosine dyes, etc. Another technique to increase the opacifying capaicty of the light-reflective layer is to employ a separate opaque layer underneath it omprising, e.g., carbon black, nigrosine dyes, etc., dispersed in an alkaline solution-permeable polymeric matrix such as, for example, gelatin, polyvinyl alcohol, and the like. Such an opaque layer would generally have a density of at least 4 and preferably greater than 7 and would be substantially opaque to actinic radiation. The opaque layer may also be combined with a developer scavenger layer if one is present. The light-reflective and opaque layers are generally 1 to 6 mils in thickness, although they can be varied depending upon the opacifying agent employed, the degree of opacity desired, etc.

When transparent sheets are used in film assemblies of this invention, they can be any transparent material as long as it does not deleteriously affect the photographic properties of the film unit and is dimensionally stable. Typical actinic radiation-transmissive flexible sheet materials include cellulose nitrate film, cellulose acetate film, poly(vinyl acetal) film, polystyrene film, poly(ethyleneterephthalate) film, poly-carbonate film, poly-.alpha.-olefins such as polyethylene and polypropylene film, and related films or resinous materials, as well as glass. The transparent sheet is usually about 2 to 6 mils in thickness and may contain an ultraviolet absorber for exposure control if desired. In addition, an adhesive layer able to be activated by the processing composition may be present on the transparent sheet in order to increase its adhesion to the photosensitive element after processing.

When transparent supports are used in film assemblies of this invention, they can be any of the materials mentioned above for the transparent sheet. If desired, an ultraviolet-absorbing material can be employed in the support to prevent the dye images from fading due to ultraviolet light.

The photosensitive substances used in this invention are preferably silver halide compositions and can comprise silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide and the like, or mixtures thereof. The emulsions may be coarse- or fine-grain and can be prepared by any of the well-known procedures, e.g., single-jet emulsions, double-jet emulsions, such as Lippmann emulsions, ammoniacal emulsions, thiocyanate or thioether ripened emulsions such as those described in U.S. Pat. No. 2,222,264 by Nietz et al, 3,320,069 by Illingsworth, and 3,271,157 by McBride. Surface-image emulsions can be used or internal-image emulsions can be used such as those described in U.S. Pat. Nos. 2,592,250 by Davey et al, 3,204,313 by Porter et al, and 3,447,927 by Bacon et al. The emulsions may be regular-grain emulsions such as the type described in Klein and Moisar, J. Phot, Sci., Vol. 12, No. 5, Sept./Oct., 1964, pp. 242-251. If desired, mixtures or surface-and internal-image emulsions can be used as described in Luckey et al, U.S. Pat. No. 2,996,382.

Negative-type emulsions are generally preferred, but direct-positive emulsions can be used if desired. Typical direct-positive emulsions include those described in U.S. Pat. Nos. 2,184,013 by Leermakers, 2,541,472 by Kendall et al, 3,367,778 by Berriman, 3,501,307 by Illingsworth et al issued March 17, 1970, 2,563,785 by Ives, 2,456,953 by Knott et al and 2,861,885 by Land, British Pat. No. 723,019 by Schouwenaars, and U.S. Ser. Nos. 123,005 by Evans filed Mar. 10, 1971, now U.S. Pat. No. 3,761,276, 123,006 by Milton filed Mar. 10, 1971, now U.S. Pat. No. 3,761,266, 123,007 by Gilman et al filed Mar. 10, 1971, now U.S. Pat. No. 3,761,267, 154,154 by Collier et al filed June 17, 1971, now U.S. PAt. No. 3,726,140, 154,155 by Gilman et al filed June 17, 1971, now abandoned and 154,224 by Gilman et al filed June 17, 1971, now U.S. Pat. No. 3,730,723.

Generally, in the photographic elements referred to above, a positive image record is obtain in an image-receiving layer by mordanting the diffusible image-providing material which is not immobilized or remains diffusible in the photosensitive portion of the film unit. It is also appreciated that the photosensitive element contains an image record which provides a useful image product. In one instance, the mobile or diffusible materials can be washed out after exposure to produce a negative image record. In another embodiment, the silver halide emulsion can be selected to produce a positive image record in the photosensitive portion of the film element.

The invention can be further illustrated by the following examples wherein the compounds identified by roman numerals are further identified structurally in the foregoing specification.

EXAMPLE 1

A. preparation of Intermediate I-A ##SPC15##

A suspension of 12.4 g. (0.04 M.) of compound 1 in 50 ml. dry benzene is refluxed with 10 ml. thionyl chloride for 30 minutes. The benzene is removed, yielding an oil which is treated with 10.8 g. (0.04 M.) of compound 2 and 5 ml. of N,N-dimethylaniline in acetone solution. This mixture is allowed to stand overnight, the solvent is removed and the residue is recrystallized from acetonitrile to yield 12.4 g. of solid (Intermediate I-A), m.p. 163-167.degree. C. Thin-layer chromatography shows one component. The IR spectrum agrees with the assigned structure.

B. preparation of Intermediate I-B

A suspension of 8.4 g. (0.015 M.) of Intermediate I-A in 300 ml. of dimethoxyethane is treated with 0.58 g. (0.015 M.) of NaH dispersion. After stirring for 30 minutes, 5.9 g. (0.015 M.) of compound 4 is added and the mixture is allowed to stand overnight. The solvent is removed, yielding an oil which is dissolved in chloroform and filtered through a silica gel pad. After removal of the solvent, the residue is recrystallized from benzene-cyclohexane to give 3 g. of Intermediate I-B. Thin-layer chromatography shows one component. The IR spectrum agrees with the assigned structure. Compound 4 is: ##SPC16##

C. preparation of Compound I (shifted yellow indophenol dye developer)

A solution of 10 g. (0.012 M.) of Intermediate I-B in 200 ml. of methanol is refluxed for 1 hour in a nitrogen atmosphere with 2.8 g. (0.05 M.) of potassium hydroxide dissolved in water. After cooling, the reaction mixture is acidified with acetic acid and extracted with ether. The ether extract is concentrated to an oil, then recrystallized from benzene-ethyl acetate-cyclohexane to give 1 g. of Compound I. Thin-layer chromatography shows one component. The NMR and IR spectra agree with the assigned structure.

EXAMPLE 2

This example demonstrates in a nonimage-forming format the property of a shifted dye developoer of undergoing a spectral-absorption change upon contact with a mordant such as an organic 'onium compound.

A. A supported single-layer gelatinous coating, containing 250 mg. of gelatin and 70 mg. of Compound I per square foot of coating, is dried and spectrophotometrically evaluated. The spectrophotometric absorption profile of Compound I contained in the so-prepared coating is represented by Curve A in FIG. 2.

B. A sample of the above-described coating is immersed for 1 minute in a mordant solution whose composition is given below:

hexadecyltrimethylammonium bromide 5 g. K.sub.2 HPO.sub.4 (0.5 M.) 430 ml. KH.sub.2 PO.sub.4 (1.5 M.) 70 ml. water to 1 liter pH = 7.0

Upon removal from the solution, the sample is dried and spectrophotometrically evaluated. The absorption profile of Compound I in the so-treated sample is represented by Curve B in FIG. 2.

A comparison of Curves A and B in FIG. 2 shows the compound's initial low absorption and its desirable final high absorption of blue light.

EXAMPLE 3

This example deomonstrates in a nonimage-forming format the trannsfer of an initially shifted dye developer to a receiver and the production of a modanted dye in the receiver.

A. a sample of the gelatin coating described in section (A) of Example 2 is brought into intimate contact for 30 seconds with a mordanted receiver, a coacervate of N-n-hexadecyl-N-morpholinium ethosulfate and methyl-tri-n-dodecylammonium p-toluenesulfonate in the presence of the following viscous processing fluid:

potassium hydroxide 30 g. hydroxyethyl cellulose 30 g. water to 1 liter

Upon separation of the gelatin coating from the receiver, the latter contains a uniformly distributed dense yellow dye. The receiver is washed for 3 minutes without appreciable change in the appearance of the yellow dye.

EXAMPLE 4

A supported multilayer photographic element is coated as follows:

1. support;

2. layer containing 250 mg./ft..sup.2 of gelatin, 70 mg./ft..sup.2 of Compound I and 70 mg./ft..sup.2 of diethyl lauramide;

3. layer containing 250 mg./ft..sup.2 of gelatin and a silver halide emulsion at 200 mg./ft..sup.2 of silver;

4. layer containing 80 mg./ft.2 of gelatin.

A sample of the above-described coating is exposed through a graduated-density test object and processed in the presence of a viscous developing solution whose composition is shown below, while in contact for 30 seconds with a receiver containing the mordant of Example 3. Upon separation of the coating sample from the receiver, the latter contains a well-defined positive yellow umage of the photographed test object.

______________________________________ Developing Solution ______________________________________ sodium hydroxide 20 g. 1-phenyl-4-methyl-4-hydroxymethyl-3- 0.75 g. pyrazolidone hydroxyethyl cellulose 25 g. water to 1 liter pH 13.7 ______________________________________

EXAMPLE 5

A. A first section of a sample of the silver halide emulsion coating described in Example 4 is uniformly flashexposed. A second section remains unexposed. The sample is brought into intimate contact for 30 seconds with the coacervate mordant receiver described in section (A) of Example 3 in the presence of a viscous processing liquid consisting of 20 g. of sodium hydroxide, 25 g. hydroxyethyl cellulose and 0.75 g. 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone per liter of aqueous solution.

Upon separation of the coating sample from the receiver, the latter contains a dense yellow dye in the area which, during the transfer cycle, has been opposite the unexposed section of the emulsion coating. The rceiver is washed for 3 minutes without appreciable change in the apperance of the yellow dye.

B. When the procedure described in section (A) above is repeated with a processing liquid which consists of only 40 g, potassium hydroxide and 30 g. hydroxyethyl cellulose per liter of solution, (i.e., the auxiliary developing agent has been omitted), the receiver contains yellow dye in both areas of contact. In this embodiment, the auxiliary developing agent is desirable to provide immobilizing reactions to obtain good image discrimination.

EXAMPLE 6 ##SPC17##

A solution (6-1) in dry tetrahydrofuran is treated with a mixture of thionyl chloride and N,N-dimethylformamide in dry benzene and heated for 30 minutes. The solvent is removed under reduced pressure to give the acid chloride, m.p. 50-53.degree. C. The acid chloride is dissolved in dry dioxane and added to a mixture of (6-2) and quinoline in dry dioxane. After standing at room temperature, the solid is collected and recrystallized from acetonitrile to give Intermediate 6-A, m.p. 198-200.degree. C.

A solution of Intermediate 6-A in tetrahydrofuran is treated with (6-3), followed by a solution of sodium bicarbonate in water and methyl alcohol and stirred for 1 hour. Water is added, the solid is collected, dissolved in chloroform and chromatographed on silica gel to give Compound 6, m.p. 136-137.degree. C. Compound (6-3) is as follows: ##SPC18##

Compound 6 is as follows: ##SPC19##

Compound 6 is incorporated in a gelatin layer coated on a support and is found to transfer a cyan dye to a quaternary mordant when contacted with an alkaline processing solution with a pH of 14. The dye remains cyan when the pH is then adjusted to about 7.

EXAMPLE 7

Preparation of a Magenta Shifted Dye Developer ##SPC20##

A suspension of (7-b 1) in dry benzene is refluxed with thionyl chloride and N,N-dimethylformamide for 20 minutes. The solvent is removed under reduced pressure and the residue is dissolved in acetic acid and added to a solution of (7-2) and sodium acetate in acetic acid. The mixture is stirred for 2 hours, allowed to stand overnight, then poured into water. After neutralizing with sodium bicarbonate, the solid is collected and recrystallized from ethyl acetate to give Intermediate 7-A, m.p. 135-136.degree. C.

A solution of Intermediate 7-A in ethyl acetate and tetrahydrofuran is treated with sodium bicarbonate, followed by Compound 7-3), then stirred for 1 hour. Water is added, the mixture is filtered through celite and the filtrate is extracted with chloroform. After washing with water, the organic layer is separated, dried and concentrated under reduced pressure. The residue is chromatographed on silica gel to yield Intermediate 7-B.

Compound (7-D) is as follows: ##SPC21##

A solution of Intermediate 7-B in tetrahydrofuran and pyridine is treated with a 3% sodium carbonate solution and refluxed for 5 hours under a nitrogen atmosphere. After cooling, the solution is poured into a dilute acetic acid solution and the solid is collected to give Compound II identified above.

In certain embodiments according to this invention, the shifted dye developers of this invention can be prepared as illustrated in the following example by further reacting the oxichromic compounds of Lestina and Bush, U.S. Ser. No. 206,949, entitled "Oxichromic Compounds, Stabilized Oxichromic Compounds and Processes for Preparing Same" filed Dec. 10, 1971, and incorporated herein by reference, now abandoned and refiled as U.S. Ser. No. 426,177.

EXAMPLE 8

The oxichromic compound 4-(3,5-dichloro-4-hydroxyanilino)-2-[5-(2,5-dihydroxyphenyl)pentanoylamido ]-5-(4-pentoxy-benzamido)phenol (1.449, 2.11 .times. 10.sup..sup.-3 moles), prepared according to Lestina and Bush, U.S. Ser. No. 206,949, Example 2, is dissolved in 300 ml. of a mixture of 80% by volume acetonitrile and 20% by volume N,N-dimethylformamide and the solution is made 0.1 molar with sodium perchlorate. The solution is oxidized by controlled potential electrolysis in a two-compartment cell using a potentiostat for control and platinum electrodes at a potential of +0.55 v. until the current has decayed to 10% of its original value. The progress of the reaction is monitored by occasionally recording a current-voltage curve. After 375.1 coulombs (2.05 electrons/molecule have passed, the first oxidation wave (E.sub.1) of the lecuo dye has diminished to approximately 5% of its original height, whereas the second wave (E.sub.2) has retained its original height. The red solution is filtered and water is added dropwise, causing precipitation of the product. The red solid is collected by filtration, washed several times with water and dried under reduced pressure. The yield is 1.4 g. or about 100%. The current yield is also 100%. After recrystallization from ethanol, m.p. = 200-201.degree. C.

The compound has the formula: ##SPC22##

EXAMPLE 9

The shifted dye developer of Example 8 is coated and tested as follows:

A. a nonsilver coating is made on a cellulose acetate support with the following layers coated in order:

1. layer containing 125 mg./ft..sup.2 of gelatin, 75 mg./ ft..sup.2 of diethyl lauramide and 50 mg./ft..sup.2 of Compound IV;

2. overcoat containing 80 mg./ft..sup.2 of gelatin.

B. a coating containing a silver halide emulsion is prepared by coating on a cellulose acetate support the following layers:

1. layer containing 125 mg./ft..sup.2 of gelatin, 75 mg./ft..sup.2 of diethyl lauramide and 50 mg./ft..sup.2 of Compound IV;

2. layer containing a monodispersed silver bromide emulsion at 100 mg. of Ag/ft..sup.2, 10 mg./ft..sup.2 of 1-phenyl-3-pyrazolidone and 100 mg./ft..sup.2 of gelatin;

3. overcoat containing 80 mg./ft..sup.2 of gelatin.

The nonsilver coating is evaluated on a spectrophotometer and gives .lambda.max at 590 nm. with a Dmax of 0.55 which is shown as line A of FIG. 3.

A portion of the nonsilver coating is soaked in a 5% 1-phenyl-3-pyrazolidone solution (H.sub.2 O and methanol) for 5 minutes wherein the color substantially disappears. A spectrophotometric absorption curve of this coating is shown as line B of FIG. 3.

One set each of the untreated coating and the coating treated with 1-phenyl-3-pyrazolidone is processed in contact with a receiver sheet containing the mordant N-n-octadecyltributylammonium bromide, using a 0.003 inch undercut roller assembly and a processing composition made as follows:

potassium hydroxide 40 g. hydroxyethyl cellulose 30 g. water to make 1 liter

The receiver sheet is peeled from the coated sample after processing with substantially no dye image apparent in the treated coating. After about 2-5 seconds' exposure to air, the reflective density of the dye transferred from the treated sample is 2.40 with a 30-second transfer, whereas the density from the untreated sample is 1.80 after a 5-minute transfer as evidenced by line C of FIG. 3.

The coatings containing the silver halide emulsion are given a stepped exposure and processed for 60 seconds with the processing composition above while in contact with the mordanted receiver sheet above.

There is substantially no dye in the receiver immediately after the receiver sheet is peeled from the photosensitive element. However, after 2-5 seconds of contact with air substantial dye density is observed in the receiver sheet.

The incorporation of the reducing agent 1-phenyl-3-pyrazolidone in the photographic element, along with the shifted indophenol dye developer, appears to provide substantially no absorption of light by the shifted dye developer and also provides faster transfer of dye to the image-receiving layer.

When the untreated coatings are developed with a processing solution containing 5 g. per liter of ascorbic acid (reducing agent), fast transfer times are also obtained.

EXAMPLE 10

The oxichromic compound 4-(3,5-dichloro-4-hydroxyanilino)-3-{3-[5-(2,5-dihydroxyphenyl)pentanoylam ido]phenylcarbamoyl}-1-phenyl-2-pyrazoline-5-one, prepared according to Example 1-C of Stern and Machiele, U.S. Ser. No. 206,926 filed Dec. 10, 1971, and incorporated herein by reference, is subjected to hydrogenolysis to remove the masking groups on the developing moiety according to Example 1-F of Stern and Machiele, U.S. Ser. No. 206,926, and then subjected to aerial oxidation to produce the shifted dye believed to have the formula: ##SPC23##

Compound V

EXAMPLE 11:

The shifted indophenol dye developers can be incorporated into the multicolor photosensitive element of a film transfer unit as disclosed in U.S. Pat. No. 2,983,606, Belgian Pat. Nos. 757,959 and 757,960 granted Apr. 23, 1971, or Lestina and Bush, U.S. Ser. No. 206,836 filed Dec. 10, 1971, entitled "Oxichromic Compounds," now abandoned and refiled as U.S. Ser. No. 308,869, all of which are incorporated herein by reference. Compound V is incorporated in association with a green-sensitive silver halide emulsion, Compound IV is incorporated in association with the red-sensitive silver halide emulsion and Compound I is incorporated in association with the blue-sensitive silver halide emulsion layer. Compounds I, IV and V can be coated in the respective silver halide emulsion layers, on the exposure side of the silver halide emulsion layers, or under the emulsion layer with respect to exposure; however, the first two locations are preferred. An auxiliary developer and preferably a reducing agent, such as 1-phenyl-3-pyrazolidone, are incorporated in the photographic element in association with the respective shifted dye developers.

The image-receiving layer contains a dye mordant which is preferably an 'onium compound. Suitable 'onium mordants are in coacervate of N-n-hexadecyl-N-morpholinium ethosulfate and methyl-tri-n-dodecylammonium p-toluenesulfonate, the mordant N-n-octadecyltributylammonium bromide, and the like.

Good three-color image transfers are obtained upon processing with an alkaline processing solution and the image dyes remain stable even when the pH is reduced to about 7.

Although the invention has been described in considerable detail with particular reference to certain preferred embodiments thereof, variations and modifications can be effected within the spirit and scope of the invention.

Claims

We claim:

1. A photographic element comprising a support and at least one layer thereon containing a photographic silver halide having associated therewith a dye developer which is diffusible in an alkaline processing medium and has the general formula:

D-(SID)

wherein D- is an aromatic nucleus polysubstituted with hydroxy groups, amino groups or alkylamino groups to provide a group which is capable of developing silver halide, and (SID) is an indophenol dye moiety.

2. A photographic element according to claim 1 wherein (SID) is a group having the formula:

(COUP)=N--Ar--OH

wherein (COUP) is a color coupler connected to the nitrogen atom at its coupling position and Ar is an arylene group containing from 6 to 20 carbon atoms.

3. A photographic element according to claim 2 wherein Ar is a phenylene group.

4. A photographic element according to claim 1 which comprises at least one layer containing an 'onium salt in water-permeable association with said dye developer.

5. A photographic element according to claim 1 wherein D comprises an aromatic nucleus which contains at least two substituents thereon from the class of hydroxy groups, primary amino groups or alkylamino groups.

6. A photographic element according to claim 1 wherein D- is a hydroquinone group.

7. A photographic element according to claim 1 wherein said element comprises at least two separate layers containing a silver halide emulsion, each having a separate dye developer of said formula associated therewith.

8. A photographic element according to claim 1 wherein said element comprises a blue-sensitive silver halide emulsion layer having associated therewith a yellow-forming indophenol dye developer, a green-sensitive silver halide emulsion layer having associated therewith a magenta-forming indophenol dye developer, and a red-sensitive silver halide emulsion layer having associated therewith a cyan-forming indophenol dye developer.

9. A photographic element according to claim 8 wherein said cyan-forming dye developer, said magenta-forming dye developer and said yellow-forming dye developer are each of said formula:

D-(SID)

and said element contains an image-receiving layer.

10. A photographic element according to claim 2 wherein Ar is a phenylene group and said OH group is para to said nitrogen atom.

11. A photographic element according to claim 1 wherein said dye developer has the formula:

D-(PYZ)=N--Ar--OH

wherein D- is an aromatic nucleus polysubstituted with hydroxy groups, primary amino groups or alkylamino groups to provide a group which is capable of developing silver halide, Ar is a phenylene group, and (PYZ) is a pyrazolone coupler radical or a pyrazolotriazole coupler connected at its coupling position to said nitrogen atom.

12. A photographic element according to claim 1 wherein said dye developer has the formula:

D-(KMC)=N--Ar--OH

wherein D- is an aromatic nucleus polysubstituted with hydroxy groups, primary amino groups or alkylamino groups to provide a group which is capable of developing silver halide, Ar is a phenylene group, and (KMC) is an open-chain ketomethylene coupler radical connected at its coupling position to said nitrogen atom.

13. A photographic element according to claim 1 wherein said dye developer has the formula:

D-(PhC)=N--Ar--OH

wherein D- is an aromatic nucleus polysubstituted with hydroxy groups, primary amino groups or alkylamino groups to provide a group which is capable of developing silver halide, Ar is a phenylene group, and (PhC) is a phenolic coupler radical connected at its coupling position to said nitrogen atom.

14. A photographic film unit comprising:

a. a photosensitive element comprising a support having thereon a layer containing a silver halide composition having associated therewith a dye developer which is diffusible in an alkaline processing medium and has the formula:

D-(SID)

wherein D- is an aromatic nucleus polysubstituted with hydroxy groups, primary amino groups or alkylamino groups to provide a group which is capable of developing silver halide, and (SID) is an indophenol dye moiety;

b. a dye image-receiving layer; and

c. means for discharging an alkaline processing composition within said film unit.

15. The film unit of claim 14 wherein said image-receiving layer is located in said photosensitive element between said support and any said silver halide composition layer.

16. A film unit according to claim 14 containing an 'onium salt in liquid-permeable association with said dye developer and which is sequestered from said dye developer until contact with said liquid processing composition.

17. The film unit of claim 14 wherein said photosensitive element comprises a support having thereon:

a. a red-sensitive silver halide emulsion layer having associated therewith a cyan-forming dye developer;

b. a green-sensitive silver halide emulsion layer having associated therewith a magenta-forming dye developer; and

c. a blue-sensitive silver halide emulsion layer having associated therewith a yellow-forming dye developer.

18. A film unit according to claim 14 wherein said dye image-receiving layer is coated on a separate support and is adapted to be superposed on said photosensitive element after exposure thereof.

19. A film unit according to claim 14 wherein said image-receiving layer is coated adjacent said silver halide emulsion layers with an opaque layer between said silver halide emulsion layers and said image-receiving layer.

20. A film unit according to claim 14 wherein said discharging means comprises a rupturable container and is so positioned during processing of said film unit that a compressive force applied to said container by pressure-applying members will effect a discharge of the container's contents between said dye image-receiving layer and the layer most remote from the support of said photosensitive element.

21. A film unit according to claim 14 wherein said discharging means comprises a rupturable container and is so positioned during processing of said film unit that a compressive force applied to said container by pressure-applying members will effect a discharge of the container's contents between the layer most remote from the support of said photosensitive element and a cover sheet superposed on said photosensitive element.

22. A photographic film unit according to claim 14 wherein said dye developer has the formula: ##SPC24##

23. A photographic film unit according to claim 14 wherein said dye developer has the formula: ##SPC25##

24. A photographic film unit according to claim 14 wherein said dye developer has the formula: ##SPC26##

25. A process for producing a photographic transfer image comprising:

a. imagewise-exposing a photosensitive element comprising a support having thereon a layer containing a silver halide composition having associated therewith a dye developer which is diffusible in an alkaline processing medium and has the formula:

D-(SID)

wherein D- is an aromatic nucleus polysubstituted with hydroxy groups, amino groups or alkylamino groups to provide a group which is capable of developing silver halide, and (SID) is an indophenol dye moiety;

b. treating said photosensitive element with an alkaline processing composition to effect development of said exposed silver halide composition layer;

c. forming an imagewise distribution of said dye developer as a function of development of said silver halide composition layer;

d. at least a portion of said imagewise distribution of diffusible dye developer diffusing to an image-receiving layer; and

e. contacting said dye developer with an 'onium compound at some point after imagewise exposure.

26. A process according to claim 25 wherein said image-receiving layer contains an 'onium compound.

27. The process of claim 25 wherein said treatment step b) is effected by:

a. superposing over the layer outermost from the support of said photosensitive element said image-receiving layer coated on a support;

b. positioning a rupturable container containing said alkaline processing composition between said exposed photosensitive element and said image-receiving layer; and

c. applying a compressive force to said container to effect a discharge of the container's contents between said outermost layer of said exposed photosensitive element and said image-receiving layer.

28. The process of claim 25 wherein said support is transparent and said image-receiving layer is located between said support and said silver halide composition layer, and said treatment is effected by applying a compressive force to a rupturable container located between the outermost layer of said photosensitive element and a transparent superposed cover sheet, and wherein said container contains an alkaline processing composition which is discharged by said compressive force.

29. A process according to claim 25 wherein development of said exposed silver halide composition layer is carried out with an auxiliary developer present in said layer.

30. A photographic product comprising a support having thereon an image receiving layer which contains an imagewise distribution of an 'onium indophenoxide of the formula:

D-(SID) .sup.- .sup.+M

wherein D- is an aromatic nucleus polysubstituted with hydroxy groups, amino groups or alkylamino groups to provide a group which is capable of developing silver halide, (SID) is an indophenol dye moiety, and M is an 'onium group.

31. A photographic product according to claim 30 wherein M is a quaternary ammonium group.

32. A photographic product according to claim 30 wherein said 'onium indophenoxide has the formula:

D-(COUP)=N--Ar--O.sup.- .sup.+ M

wherein D- is an aromatic nucleus polysubstituted with hydroxy groups, amino groups or alkylamino groups to provide a group which is capable of developing silver halide, (COUP) is a photographic color coupler, Ar is an arylene group containing from about 6 to about 20 carbon atoms, and M is an 'onium group.

33. A photographic product according to claim 32 wherein (COUP) is an open-chain ketomethylene color coupler group connected at its coupling position to said nitrogen atom.

34. A photographic product according to claim 32 wherein (COUP) is a pyrazolone or pyrazolotriazole color coupler group connected at its coupling position to said nitrogen atom.

35. A photographic product according to claim 32 wherein (COUP) is a phenolic color coupler connected at its coupling position to said nitrogen atom.

36. A photographic product according to claim 30 which contains 1) an 'onium indophenoxide of said formula wherein (SID) comprises a phenolic color coupler, 2) an 'onium indophenoxide of said formula wherein (SID) comprises an open-chain ketomethylene color coupler and 3) an 'onium indophenoxide of said formula wherein (SID) comprises a pyrazolone or pyrazolotriazole color coupler.

37. A photographic product according to claim 30 wherein said image-receiving layer comprises a polymer with 'onium groups thereon.

38. A photographic product according to claim 30 wherein said M represents an immobile 'onium compound which is present in said image-receiving layer at concentrations of about 25 mg. to 1000 mg. per square foot.

39. A photographic product according to claim 30 wherein D- is a hydroquinone group or an oxidized hydroquinone group.