US3909263A

US3909263A - 5,5{40 ,6,6{40 -Tetrahydroxy-3,3,3{40 ,3{40 -tetramethyl-bis-spirohydrindene auxiliary developers

Info

Publication number: US3909263A
Application number: US424961A
Authority: US
Inventors: Yoshinobu Yoshida; Tadao Shishido
Original assignee: Fuji Photo Film Co Ltd
Current assignee: Fujifilm Holdings Corp
Priority date: 1972-12-14
Filing date: 1973-12-14
Publication date: 1975-09-30
Anticipated expiration: 1992-09-30
Also published as: GB1445893A; JPS4984238A; DE2362372A1; JPS5438892B2

Abstract

A photographic diffusion transfer color process comprising image exposing a photographic material having at least a silver halide emulsion layer and a layer containing a dye developer adjacent the silver halide emulsion layer and then treating the exposed silver halide emulsion layer with an alkaline solution to immobilize the dye developer at the exposed area while the dye developer at the unexposed area of the silver halide emulsion layer is transferred by diffusion to an image-receiving material, wherein the alkaline solution treatment is conducted in the presence of 5,5'',6,6''-tetrahydroxy-3,3,3'',3''-tetramethyl-bis1,1''-spirohydrindene.

Description

[451 Sept. 30, 1975 5,5 ',6,6'-TETRAHYDROXY-3,3,3 ,3-

TETRAMETHYL-BISSPIROHYDRINDENE AUXILIARY DEVELOPERS [75] Inventors: Yoshinobu Yoshida; Tadao Shishido,

both of Minami-ashigara, Japan [73] Assignee: Fuji Photo Film C0., Ltd., Minarniashigara, Japan [22] Filed: Dec. 14, 1973 [21] Appl. No.: 424,961

[30] Foreign Application Priority Data Dec. 14, 1972 Japan 47-125611 [52] US. Cl 96/3; 96/29 D; 96/66 R UXj 96/66.3 UX; 96/77; 96/95; 96/99 [51] Int. CL? ..G03C 7/00; 603C 5/54; 003C 5/30; (303C 1/40 [58] Field of Search 96/66 R, 66.3, 29 D, 77, 96/3, 95, 99

[56] References Cited UNITED STATES PATENTS 2,983,606 5/1961 Rogers 96/29 D 3,440,049 4/1969 Moede 96/66 R Primary E.\'aminerNorman G. Torchin Assistant ExaminerRichard L. Schilling Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak l 5 7 1 ABSTRACT A photographic diffusion transfer color process comprising image exposing a photographic material having at least a silver halide emulsion layer and a layer containing a dye developer adjacent the silver halide emulsion layer and then treating the exposed silver halide emulsion layer with an alkaline solution to immobilize the dye developer at the exposed area while the dye developer at the unexposed area of the silver halide emulsion layer is transferred by diffusion to an image-receiving material, wherein the alkaline solution treatment is conducted in the presence of 5,5,6,- 6'-tetrahydroxy-3,3,3 ,3 '-tetramethyl-bis- 1 ,1 spirohydrindene.

16 Claims, No Drawings 5 ,5 ',6,6'-TETRAHYDROXY-3,3,3 ,3 TETRAMETHYL-BIS-SPIROHYDRINDENE AUXILIARY DEVELOPERS BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved photographic diffusion transfer color process and, more particularly, the invention relates to a photographic diffusion transfer color process using a dye developer.

2. Description of the Prior Art A photographic diffusion transfer color process using a dye developer, that is a dye which is a developer for silver halide, is disclosed in, e.g., the specifications of US. Pat. No. 2,983,606 and British Pat. No. 804,971. As described in the specifications of the aboveillustrated patents, a photosensitive silver halide emulsion layer of a photographic material which is image exposed is developed in the presence of a dye developer, whereby an image-like distribution of the unoxidized dye developer is formed as the function of the development. The unreacted unoxidized dye developer is rendered mobile in a processing solution and thus atleast a part of the imagewise distributed dye developer is transferred to an image-receiving element which is in a superposed relation with the silver halide emulsion layer,

In a particularly useful embodiment of such a diffusion transfer process, a photosensitive element having a silver halide emulsion and a dye developer is exposed and then a liquid processing composition is applied thereto by immersion, coating, spraying, etc. The exposed photosentive element is superposed on an imagereceiving element which is dyeable by the dye developer, prior to, during, or after the application of the liquid processing composition. In a preferred embodiment, the photosensitive element contains the dye developer in a layer adjacent to and behind the silver halide emulsion layer to the incident light. The photosensitive element is superposed on an image-receiving element so that the silver halide emulsion layer is brought into contact with the image-receiving layer and a liquid processing composition is supplied between the phososensitive element and the image-receiving element by spreading it as a comparatively thin layer. The liquid processing composition permeates the emulsion layer and the dye developer-containing layer to initiate the development of the developable silver halide, whereby the dye developer which developes the silver halide is immobilized.

This immobilization is apparently, at least in part,

, due to the reduction of the mobility or solubility of the oxidation product of the dye developer as compared with those of the unoxidized dye developer. The immobilization is also, at least in part, due to the localized reduction in an alkali concentration as a function of development.

In the unexposed areas of the emulsion layer, the dye developer is diffusible and thus provides an imagewise distribution of the diffusible unoxidized dye developer as a function of the exposure and the development of the silver halide emulsion layer. At least part of this imagewise distribution of the diffusible unoxidized dye developer is transferred to a superposed imagereceiving layer, the transfer of which is clearly distinguished from that of the less-diffusible oxidized dye developer, and thus a transferred image is formed on the image-receiving layer.

When a multilayer color photographic element having silver halide emulsion layers differently sensitized are associated with dye developers having substantially complementary colors to the main sensitive regions of the silver halide emulsions respectively, namely when a red-sensitive silver halide emulsion, a green-sensitive silver halide emulsion, and a blue-sensitive silver halide emulsion are associated with, respectively, a cyan dye developer, a magenta dye developer, and a yellow dye developer, and such a multilayer color photographic element is exposed and processed by a liquid processing composition, each dye developer is oxidized and immobilized in the developed areas of each associated silver halide emulsion layer. The remaining unoxidized dye developers in the undeveloped areas of the emulsion layers are transferred, by imbibition, to an imagereceiving element.

Therefore, if large quantities of unoxidized dye developers are present in sufficiently exposed negative areas corresponding to the highlight portions of a subject, they partially diffuse into the image-receiving element as unoxidized dye developers which are present in the unexposed negative areas corresponding to the dark portions of the subject to give a transferred image having a high minimum density and an indistinct contrast.

Various dye developers are disclosed in, e.g., the specifications of US. Pat. Nos. 3,255,001; 2,992,106;

3,230,082; 3,230,085, etc. For instance, a cyan dye developer l,4-bis( a-methyl-B- hydroquinonylpropylamino)-5,8-dihydroxyanthraquinone, a magenta dye developer 4-propoxy-2-[p-(B- hydroquinonylethyl)phenylazo]-l-naphthol, and a yellow dye developer l-phenyl-3-N-nhexylcarboxyamido-4-[p-2 ,5 '-dihydroxyphenethyl phenylazo1-5-pyrazolone, which are typical dye developers of the dye developers disclosed above, are weak developing agents for silver halide even when used at a comparatively strong alkaline state of about pH 13. Therefore, when such dye developers are used, the desired maximum density, gradation, and sensitivity cannot be obtained. Since the immobilization of the dye developer occurs as a function of the development of the silver halide emulsion, the transferred image obtained by the diffusion transfer process in this case shows undesirably a high minimum density, a low maximum density and a low contrast in the areas corresponding to the highlight portions of a subject. Those faults are believed to be caused partially by such factors that the developing activity of the dye developers as developing agent for silver halide is weak, the effective utilization of all of the dye developers around the silver is difficult, etc.

Furthermore, in a multi-color system, it sometimes occurs that a silver halide emulsion layer is developed not only by the dye developer having a substantially complementary color to the main sensitive region of the silver halide emulsion but also by other dye developers associated with other silver halide emulsion layers. For instance, a magenta dye developer is associated with a green-sensitive silver halide emulsion layer but part of the magenta dye developer diffuses into a blue-sensitive emulsion layer and a red-sensitive emulsion layer to develope the silver halide in these emulsion layers and is immobilized there, which results in a transferred image having less magenta dye.

The specifications of Japanese Pat. Nos. 4839/1970, 10240/1969, 2241/1962, etc., disclose that the aforementioned fault can be improved to some extent by incorporating a colorless auxiliary developing agent, such as l-phenyl-3-pyrazolidone, in a liquid processing composition to promote the development of the silver halide and promote the immobilization of the dye developers in a photosensitive element. Furthermore, the specifications of Japanese Pat. Nos. 29130/1964 and 13837/1968 disclose the use of hydroquinones such as -4'-methylphenylhydroquinone and the specification of British Pat. No. 1,243,539 discloses use of cathecols such as 4-methylcathecol as the auxiliary developing agent. However, the extent of improvement obtained by the employment of the auxiliary developing agents as described in the aforesaid patents is not sufficiently satisfactory and, in particular when such auxiliary developing agents are used in multicolortype multilayer color photographic element, each dye developer does not advance the development to the necessary stage and to the ratio required in each specific emulsion layer, which results in, therefore, making the formation of a'satisfactory multicolor transferred image difficult. Moreover, it has frequently been observed that a part of the auxiliary developing agent is transferred to an image-receiving element to cause the formation of stains in the color image formed.

SUMMARY OF THE INVENTION As the results of various investigations of discovering a diffusion transfer color process in which the difficulties as described above are eliminated, the inventors succeeded in discovering the process of this invention. That is to say, according to the present invention, there is provided a photographic diffusion transfer color process comprising imagewise exposing a photographic material having at least one silver halide emulsion layer and at least a dye developer associated with the silver halide in the'silver halide emulsion layer and then, in the presence of 5,5',6,6'-tetrahydroxy-3,3,3,3'- tetramethyl-bis- 1 ,1 '-spirohydrindene, processing the exposed photographic material with an alkaline com- I" position to immobilize the dye developer in the exposed areas of the silver halide emulsion layer and transferring, by diffusion, the dye developer in the unexposed areas of the silver halide emulsion layer to an image-receiving material.

DETAILED DESCRIPTION OF THE INVENTION The 5,5 ,6,6 '-tetrahydroxy-3,3,3 ,3 -tetramethyl-bis- 1,1 -spirohydrindene used in this invention is substantially a colorless compound and the compound is hereinafter designated an auxiliary developing agent to distinguish it from a dye developer. The auxiliary developing agent can be present in a negative photosensitive element containing a dye developer, in a liquid processing composition or in an image-receiving element but it is preferable that the auxiliary developing agent be in the negative photosensitive element containing the dye developer. In this case, various methods have been employed for incorporating the auxiliary developing agent in a hydrophilic colloid layer of the negative photosensitive element. For instance, the auxiliary developing agent used in this invention can be dissolved in a waterimmiscible high boiling organic solvent and coated on a support a fine dispersion of the solution in an aqueous hydrophilic colloid solution. Furthermore, the auxiliary developing agent can be dissolved in an alkaline aqueous solution and applied to a support as a mixture with an aqueous hydrophilic colloid solution.

It is desired that the multilayer diffusion transfer color photographic material have on a support a redsensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer, and a blue-sensitive silver halide emulsion layer, successively, and each of the emulsion layers have associated therewith a cyan dyev developer, a magenta dye developer, and a yellow dye developer, respectively. Also, if desired, the multilayer color photographic material can have further a yellow filter layer, an antihalation layer, intermediate layers, and a protective layer. Examples of multilayer diffusion transfer color photographic materials and their configurations are disclosed in U.S. Pat. Nos. 2,983,605;

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; 3,345,135; and

The silver halide emulsion used in the present invention is a colloidal dispersion of silver chloride, silver bromide, silver chlorobromide, silver iodobromide or silver chloroiodobromide or a mixture thereof. The composition of the halide is selected depending on the purpose to which the element is to be applied and treatment conditions of the sensitive material. Particularly, a silver iodobromide or chloroiodobrimide emulsion consisting of 1-10 mol of iodide, less than 30 mol of chloride and a balance of bromide is preferred. The mean particle size of the emulsion is usefully within a range of about 0.1 to about 2 microns and a uniform particle size is desirable depending on the end use purpose of sensitive material. Particles are of a cubic, an octahedral or a mixed crystal system. These silver halide emulsion can be prepared using conventional techniques, for example, as disclosed in P. Glafkides: Chimie Photographique, Chap. 18-23, 2nd edition, 1957, Paul Moncle, Paris. For example, a soluble silver salt such as silver nitrate and a water soluble halide such as potassium bromide are reacted in a solution of a protective colloid such as gelatin and the crystal growth accomplished in the presence of an excess of halide or a solvent for silver halide, such as ammonia. In this case, a precipitation method such as the single or double jet method or pAg control-double jet method can be used. The removal of the soluble salts from the emulsion is by washing a cooled and coagulated emulsion with water, dialysis thereof, or settlement by adding a precipitating agent such as an anionic polymer or a surface active agent having a sulfone, sulfuric acid ester or carboxylic group and controlling the pH or by using an acylated protein such as phthaloyl gelatin as the protective colloid and controlling the pH. The silver halide emulsion used in the present invention is desirably sensitized by subjecting the emulsion to a heat treatment in conjunction with sensitizers naturally contained in gelatin, a sulfur sensitizer such as sodium thiosulfate or N,N,N-trimethyl thiourea, a gold sensitizer such as thiocyanate or the thiosulfate complex salt of monovalent gold, or a reducing sensitizer such as stannous chloride or hexamethylenetetramine (for example, as described in US. Pat. Nos. 1,623,499; 2,399,083; 3,297,447; and 3,297,446). Both an emulsion, by which a latent image is easily formed on the surfaces of particles, and an emulsion as described in US. Pat. Nos. 2,592,550 and 3,206,313 etc., by which a latent image is easily formed in the interior of the particles, can be used in the present invention.

The silver halide emulsion used in the present invention can be stabilized with an additive such as 4- hydroxy-6-methyl-1,3-3a,7-tetrazaindene, 5- nitrobenzimidazole, 1-phenyI-S-mercaptotetrazole, 8 chloromercuriquinoline, benzenesulfinic acid and pyrocatechin. In addition to these compounds, inorganic compounds such as cadmium and mercury salts, and the complex salts of platinum group elements, such as the chlorine complex salt of palladium, are useful for the stabilization of the sensitive material according to the present invention. Further, the silver halide emulsion used in the present invention can contain a sensitizing compound such as polyethylene oxide compound (for example, as described in US. Pat. Nos. 3,046,134; 2,944,900; and 3,294,540).

The silver halide emulsion used in the present invention, if desired, can have its color sensitivity extended with an optical sensitizing dye. As useful optical sensitizers, there are mentioned the cyanines, merocyanines, homopolar cyanines, styryls, hemicyanines, oxanoles, hemioxanoles and the like. Examples of these optical sensitizers are described in by P. Glafkides, supra (chap. 35-41) an F. M. Hamer: The Cyanirze Dyes and Related Compounds (lnterscience). [n particular, cyanines, in which the nitrogen atom in the nucleus is substituted by an aliphatic radical having a hydroxyl, carboxyl or sulfo group, as described in US. Patents 2,503,766; 3,459,553; 3,177,210; 3,384,486; 2,526,632; 2,493,748; 2,912,329; and 3,397,060, are useful in the present invention. The dye developer is usually dissolved in a solvent or a solvent mixture, the solution obtained is then added to an aqueous solution of a hydrophilic colloid such as gelatin, the mixture is passed through a colloid mill an appropriate number. of times, and then the mixture is directly coated or is coated after cooling, solidifying, cutting, washing, and re-melting. Or, alternatively, the dispersion of the dye developer is added to a silver hal-' ide emulsion and the mixture is coated. Examples of such solvents are described in the specifications of, e.g., Japanese Patent Publication No. 13837/1968 and U.S. Pat. No. 2,322,027.

Furthermore, the compounds described in the specifications of US. Pat. Nos. 3,255,001; 3,320,063;

3,076,820; 3,173,929; 3,239,083; etc., can be used as the dye developer in this invention.

Examples of particularly useful dye developers which can be used in this invention are as follows:

4-[p-(2',5'-Dihydroxyphenyl)-phenylazo]-5- acetamidol-naphthol,

4-[p-( 2,5 '-Dihydroxyphenethyl)-phenylazoI-S-benzamidol -naphthol,

1-Phenyl-3-methyl-4-[p-(2,5'-dihydroxyphenethyl)- phenylazo]-5-pyrazolone,

2-[p-(2',5'-Dihydroxyphenethyl)-phenylazo]-4- acetamidol-naphthol,

2-[p-(2,5-Dihydroxyphenethyl)-phenylazo]-4- amino- 1 -naphthol,

2-[p-( 2,5 '-Dihydroxyphenethyl )-phenylazo]-4- methoxyl -naphthol,

2-[p-(2',5-Dihydroxyphenethyl)-phenylazo]-4- ethoxy- 1 -naphthol 1-Phenyl-3-N-n-butyl-carboxyamido-4-[p-( 2 ,5 dihydroxyphenethyl)-phenylazo]-5-pyraz0lone,

1-Phenyl-3-N-n-hexylcarboxyamido-4-[p-( 2 ,5 dihydroxyphenethyl)-phenylazo]-5-pyrazolone,

1-Phenyl-3-N-n-cyclohexylcarboxyamido-4-[p- (2,5 'dihydroxyphenethyl)-phenylazol-5pyrazolone,

1-Phenyl-3-amino-4-(4'-[p-(2",5"- dihydroxyphenethyl )-phenylazo]-2 ,5 -diethoxyphenylazo)-5-pyrazolone,

1-Acetoxy-2-[p-(B-hydroquinonyl)-phenylazo]-4- methoxynaphthalene,

4-isoPropoxy-2-[p-( B-hydroquinonylethyl phenylaz0]- l -naphthol,

1-Acetoxy-2-[p-(B-hydroquinonylethyl)-phenylazo]- 4-propoxynaphthalene,

1,4-bis( 2,5 '-Dihydroxyanilino )-anthraquinone,

1,5-bis(2',5 '-Dihydroxyanilino)-4,8-dihydroxyanthraquinone,

l,4-bis[/3-( 2,5 -Dihydroxyphenyl)-isopropylamino]- anthraquinone,

l,4-bis[fi-(2,5 '-Dihydroxyphenyl)-ethylamino]- anthraquinone,

1-Chloro-4-[B-(2,5'-dihydroxyphenyl)- ethylamino]-anthraquinone,

N-monobenzoyl-l ,4-bis[B-( 2,5 -dihydroxyphenyl ethylamino]-anthraquinone,

5,8-Dihydroxyl ,4-bis[ (B-hydroquinonyl)-methyl]ethylaminoanthraquinone, etc.

When one amino nitrogen atom of a cyan dye developer, for instance, 1,4-bis[B-(2,5'-dihydroxyphenyl)- ethylaminol-anthraquinone is acylated, the color thereof is changed to a magenta color and when both of the amino nitrogen atoms of the cyan dye developer are acylated, the color thereof is changed to an orangeyellow color. Similarly, by acylating the hydroxyl group of the aforesaid dye developer, the color of the dye developer can be changed. Thus, the dye developer can change its structure or color by, e.g., hydrolysis, during the development reaction and hence a transfer-red dye having a color different from the color of the dye developer initially present in the photosensitive element can be obtained. Examples of such dye developers are described in the specifications of US. Pat. Nos. 3,579,334; 3,307,947; 3,336,287; etc. A leuco compound such as, for instance, l-phenyl-3-methyl-4-(2'- methyl-4-diethylamino)-anilino-5-pyrazolone which does not provide a light filtering action to the silver halide emulsion layer disposed under the layer containing the leuco compound and is immobilized in a developed areas but diffuses imagewise to an image-receiving element from the undeveloped areas and is oxidized to a colored image in the image-receiving element as disclosed in U.S. Pat. Nos. 3,579,334; 3,307,947 and 3,336,287 can also be used.

The dye developer is usually present adjacent a silver halide emulsion layer of a photosensitive element. That is to say, dye developers are incorporated in one or more emulsion layers, preferably in the silver halide emulsion layers or a hydrophilic organic colloid emulsion layer directly under a silver halide emulsion layer. In a multilayer color photographic element, it is particularly effective to incorporate each dye developer in a layer under the silver halide emulsion layer of which the main sensitive region is in a complementary color relationship with the color of the dye developer. However, as described above, in using a dye developer which does not initially have a complementary color but provides a desired color in an image-receiving layer as the result of development, the dye developer can be incorporated in the silver halide emulsion layer associated therewith or can be incorporated in a layer adjacent the silver halide emulsion layer associated therewith. Furthermore, the association of the dye developer with the silver ahlide can be in the form of a mixed packet with a colloid surrounding particles or small spheres containing the silver halide particles.

As described above, the auxiliary developing agent used in this invention is preferably added to a silver halide emulsion layer, a dye developer-containing layer, an intermediate layer, a protective layer, or another layer of a photosensitive element. Most preferably, the auxiliary developing agent is dissolved in a high boiling organic solvent having a boiling point of higher than about 175C, with the auxiliary developing agent being diffusible in an alkaline processing solution, the solution is dispersed in an aqueous solution of an organic colloid such as gelatin, and then the despersion is incorporated in one or more layers of a photosensitive element.

Examples of the preferable high boiling organic solvents used for the above purposes are a phthalic acid alkyl ester in which the alkyl group has less than 6 carbon atoms, such as methyl phthalate, ethyl phthalate, propyl phthalate, n-butyl phthalate, di-n-butyl phthalate, amyl phthalate, isoamyl phthalate, dioctyl phthalate, etc., a phosphoric acid ester such as triphenyl phosphate, tricresyl phosphate, diphenyl mono-p-tertbutylphenyl phosphate, an alkylamide, etc.; and an acetanilide such as N-n-butylacetanilide, N-methyl-pmethylacetanilide, etc. Furthermore, the aforesaid high boiling organic solvent can be used together with a solvent having a boiling point at least 25C lower than the boiling point of the high boiling solvent, such as methyl acetate, ethyl acetate, butyl acetate, isopropyl acetate, ethyl propionate, secondary butyl alcohol, carbon tetrachloride, chloroform, benzyl alcohol, 2,3-methylcyclohexanone, 2,4-methylcyc1ohexanone, etc., or a solvent which is more soluble in water than the aforesaid high boiling organic solvent and has a solubility of at least 2 parts per 100 parts of water, such as methyl isobutyl ketone, B-ethoxyethyl acetate, ,B-butoxy-B- ethoxyethyl acetate, tetrahydrofurfuryl adipate, diethylene glycol monoacetate, methoxy triglycol acetate, acetonyl acetone, acetone alcohol, ethylene glycol, 2,3-methylcyclohexane, 2,4-methylcyclohexane, ethylene glycol, monomethyl ether acetate, diethylene glycol monobutyl ether, cyclohexanone, triethyl phosphate, etc.

The amount of the auxiliary developing agent which can be used in this invention depends upon the amount and nature of the dye developer used, the amount and nature of the silver halide, the layer construction of the photosensitive element, and other factors but usually the amount is 0.01 to 10 times, preferably 0.1 to 2 times the molar amount of the dye developer used. An appropriate amount of the auxiliary developing agent is 0.01 to 0.5 times the amount of the photosensitive silver halide. Also, the silver halide emulsion for the photosensitive element used in this invention can further contain a stabilizer such as 4-hydroxy-6-methyl- 1,3,3a,7-tetraazaindene, benzimidazole, benztriazole, l-phenyl-5-mercaptotetrazole, etc.; a hardening agent such as formaldehyde, mucobromic acid, dichlorotriazine, etc.; and a coating aid such as saponin, sodium alkyl benzenesulfonate, etc.

The image-receiving element dyable with dye developers from the negative photosensitive element can be suitably selected from conventional image receiving elements. As the dyeable materials suitable for the image-receiving layers of the image-receiving elements, gelatin, polyvinyl pyrrolidone, poly-4-vinylpyridine, polyvinyl acetate, polyvinyl alcohol, cellulose acetate, polyvinyl salicylate, partially hydrolyzed polyvinyl acetate, methyl cellulose, and mixtures of these materials can be used.

Typical examples of the supports which can be used for the photosensitive element and the image-receiving element are a cellulose nitrate film, a cellulose acetate film, a polyvinyl acetal film, a polystyrene film, a polyethylene terephthalate film, a polyethylene film, a polypropylene film, a paper, a polyethylene-coated paper, and glass. Furthermore, a multilayer type negative photographic element can be used as the support for the image-receiving element. The supports can be opaque or transparent depending upon the end-use desired.

It is particularly useful to associate the imagereceiving element with an acid polymer capable of releasing an acid material at a definite rate or a derivative of an acid compound as described in the specification of U.S. Pat. No. 2,584,030. Such an acid material is used in a layer under the image-receiving layer. The acid material contributes to the neutralization of the alkali in the liquid processing composition spread over the image-receiving layer. Furthermore, a spacer layer for controlling the release of the acid material can be formed between the image-receiving layer and the layer containing the acid material. Moreover, the image-receiving layer can contain further a development inhibitor such as mercaptotetrazole, iodine, etc. Imagereceiving materials are further detailed in the specifications of Japanese Pat. Nos. 8274/1963; 8449/1963; and 29756/1961 and the specifications of U.S. Pat. Nos. 3,003,872; 3,043,689; 3,065,074; 3,148,061; 3,239,337; 3,353,956; 3,362,819, etc.

The liquid processing composition for initiating the development of the exposed areas is a strongly alkaline solution having a pH of higher than 12 and containing more than 0.01 N of hydroxyl ion. In the liquid processing composition, a compound providing strong alkalinity, such as an alkali metal hydroxide, e.g., potassium hydroxide, sodium hydroxide, sodium carbonate, etc., can be used. In the case of applying the alkaline processing composition to the photographic element, preferably a comparatively thin and uniform layer by spreading, the aforesaid alkaline processing composition can contain a compound which increases the viscosity of the composition and is a film-forming material capable of forming a comparatively hard and stable film when the processing composition containing it is spread and dried. When the compound having a function of increasing the viscosity is present in the alkaline processing solution for a long period of time, a filmforming material of which the function of increasing the viscosity is not substantially influenced can be used. Preferred examples of such film-forming materials are high-molecular weight polymers, such as the watersoluble polymer ethers inert to the alkaline processing composition, for instance, hydroxyethyl cellulose, sodium carboxymethyl cellulose, etc.

In the diffusion transfer color process of this invention, it is desirable to conduct the development in the presence of a diffusible onium compound. Examples of such onium compound are quaternary ammonium .compounds, quaternary phosphorus compounds, and

quaternary sulfonium compounds. Particularly useful onium compounds are l-benzyl-Z-picolinium bromide, l-( 3 -bromop ropyl )-2-picolinium-p-toluenesulfonic acid, l-phenethyl-2-picolinium bromide, 2,4-dimethyl- 1 -phenethylpyridinium bromide, a-picoline-B- naphthoylmethyl bromide, N,N-diethylpiperidinium bromide, phenethyltrimethylphosphonium bromide, dodecyldimethylsulfonium-p-toluene sulfonate, etc. The onium compound is preferably incorporated in the alkaline processing composition. It is most preferable that the amount of the onium compound be 2 to percent by weight of the amount of the total processing composition. By conducting the development in the presence of the onium compound, the quality of the transferred image is greatly improved. Other examples of such onium compounds are described in detail in the specifications US. Pat. Nos. 3,173,786 and 3,411,904 together with the manner of using them. Furthermore, a development inhibitor such. as benzotriazole can be added to the processing composition.

The processing composition can further contain a shading agent such as titanium dioxide and carbon black. Still further, the processing composition can contain the auxiliary developing agent of this invention, as described previously.

The diffusion transfer color process of this invention can be used for a film unit in which a photosensitive element and an image-receiving element are combined as a unit. Such film units are described in the specifications of US. Pat. Nos. 3,415,644; 3,415,645;

' 3,415,646; etc.

It is believed that at least parts of the dye developers are oxidized and immobilized as the result of the reactions with the oxidation products of the auxiliary developing agents. The auxiliary developing agent is oxidized by the development of the exposed silver halide. It is further believed that the reaction of the auxiliary developing agent oxidized for furtherreaction with the exposed silver halide and the unoxidized dye developer regenerates the auxiliary developing agent. By using the auxiliary developing agent of this invention, a transferred image having an improved transfer density, having good color separation, and having less color mixing can be obtained as the result of such partial reactions.

The chemical structures of the auxiliary developing agents used in this invention resemble those of the catechol compounds as disclosed in the specification of British Pat. No. 1,243,539. However, as will be shown in Example 1 later, the auxiliary developing agents of this invention have the advantages of decreasing further the minimum density of the transferred image and increasing further the maximum density of the image as compared with the catechols and the typical derivatives thereof, such as 4-methylcatechol, 4-(t)butylca."* :L-hol, 3-methoxycatechol, 4-phenylcatechol, etc., as described in the abovementioned British patent. This advantage is not due to the fact that the compound of this invention has two hydroxybenzene groups in one molecule because by adding the compound of this invention in an amount of less than /2 mol of the catechol compound, even more excellent advantages than with the catechol compound are obtained. Furthermore, as is shown in Examples 2 and 3, the auxiliary developing agents used in this invention show remarkable effects for improving the density of the transferred image and decreasing the formation of color mixing and color stain as compared with 4-(t)butyl catechol when they are used in multilayer color photographic elements. This advantage is observed when the auxiliary developing agent used in this invention is used in a photosensitive element or in a liquid processing composition.

It is believed that such an excellent property of the auxiliary developing agent used in this invention is due to the presence of a spirocarbon in the compound.

The auxiliary developing agents used in this invention can, for instance, be prepared in the following manner.

SYNTHESIS EXAMPLE 26.4 g of 1,2-dihydroxybenzene was dissolved in a mixture of 30 ml of acetone, 60 ml of glacial acetic acid, and 48 ml of concentrated (12 N) hydrochloric acid and then the mixture was refluxed for 48 hours. The reaction product was cooled and the crystals thus formed were recovered and recrystallized from a mixed solvent of ethanol and glacial acetic acid to give 18 g of the crystals of the desired compound having a melting point of 313C.

Elementary analysis Found: C 73.97%; H 7.28%.

Calculated: C 74.09%; H 7.11%.

Now, the invention will further be explained in greater detail by referring to the following examples. Unless otherwise indicated, all parts, percents, ratios and the like are by weight unless otherwise indicated.

EXAMPLE 1 Color photographic films were prepared by applying, in succession, the following photographic layers to cellulose triacetate supports:

Film A 1. Yellow Dye Developer Layer 10 g of a yellow dye developer, 1-phenyl-3-N-nhexylcarboxyamido-4-[p-2',5'-dihydroxyphenethyl)- phenylazo1-5-pyrazolone was dissolved in a mixed solvent of 10 ml of N-n-butylacetanilide and 25ml of cyclohexanone and the solution was dispersed by emulsification in ml of an aqueous 10% gelatin solution containing 8 ml of a 5% aqueous solution of sodium n-dodecylbenzenesulfonate. After adding to the emulsion 5 ml of an aqueous solution of 5% 2-hydroxy-4,6- dichloro-S-triazine sodium salt, water was added thereto to make the total volume 300 ml. The emulsion was applied to the support so that the dry thickness of the coating was 20 microns.

2. Photosensitive Silver Halide Emulsion Layer A silver iodobromide emulsion (containing mol percent silver iodide) containing 6.5 g of gelatin and 3.5 X mol of silver per 100 g of the emulsion was applied to the yellow dye developer layer in a dry thickness of 1.5 microns.

3. Protective Layer 100 ml of a 5% aqueous gelatin solution containing 2 ml of a 5% aqueous solution of sodium n-dodecylbenzenesulfonate and 5 ml of 2% mucochloric acid was applied to the silver halide emulsion layer in a dry thickness of 1.5 microns.

Film B Film B was prepared in the same way as in the case of producing Film A except that the photosensitive silver halide emulsion further contained 50 g of an emulsion prepared by dissolving 5 g of catechol in a mixture of 10 ml of tri-o-cresyl phosphate and 10 ml of ethyl acetate and dispersed by emulsification in 50 ml of a 10% aqueous gelatin solution.

Film C Film C was prepared in the same way as in the case of producing Film B except that the photosensitive silver halide emulsion contained 1.55 g of 4- methylcatechol in place of the catechol.

Film D Film D was prepared in the same way as in the case of producing Film B except that the photosensitive silver halide emulsion contained 2.08 g of 4-(t)butyl catechol in place of the catechol.

Film E Film E was prepared in the same way as in the case of producing Film B except that the photosensitive silver halide emulsion contained 1.75 g of 3- methoxycatechol in place of the catechol.

Film F Film F was prepared in the same way as in the case of producing Film B except that the photosensitive silver halide emulsion contained 2.32 g of 4- phenylcatechol in place of the catechol.

Film G Film G was prepared in the same way as in the case of producing Film 13 except that the photosensitive silver halide emulsion contained 5.40 g of the auxiliary developing agent of this invention.

Film H Film H was prepared in the same Way as in the case of producing Film B except that 2.68 g of the auxiliary developing agent of this invention was used in place of the catechol.

Each of Films A-H thus prepared was exposed gradationally to white light and after superposing an imagereceiving element as shown on the exposed film, diffusion transfer development was conducted using a liquid processing composition having the following formula:

Processing Composition:

High-viscous Hydroxyethyl Cellulose 3.5 g Sodium Hydroxide 4.5 g Benzotriazole 2.0 g l-Benzyl-Z-picolinium Bromide 2.0 g Sodium Thiosulfate 1.0 g Water to make I00 ml.

Image-receiving Element:

A solution containing 2 g of poly-4-vinylpyridine (mordant) and 0.1 of 1-phenyl-S-mercaptotetrazole in 100 g of a 10% aqueous gelatin solution was coated on a baryta-coated paper in a dry thickness of 10 microns to prepare the image-receiving element.

After one minute, the image-receiving element was separated from the photosensitive film and the blue filter reflective density of the yellow color image thus transferred to the image-receiving element was measured. The minimum density and the maximum density of the transferred image in each case are shown in the following table.

Film Minimum Density Maximum Density From the results shown in the above table, it can be seen that in Films G and H prepared using the auxiliary developing agent of this invention, the minimum density and the maximum density of the transferred color image were greatly improved and further were greatly superior to those of the films prepared using the catechol compounds.

EXAMPLE 2 Films 1, J and K were prepared in the following way.

Film 1 The multilayer type color photographic element was prepared by applying, in succession, on a cellulose t'riacetate support the photographic layer as shown below:

1. Cyan Dye Developer-containing Layer:

15 g of l,4-bis(a-methyl-'B- hydroquinonylpropylamino)-5,8-dihydroxyanthraquinone was dissolved in a mixture of 25ml of N,N- diethyllaurylamide and 25 m1 of methylcyclohexanone at C. The solution was dispersed by emulsification in 160 ml of a 10% aqueous gelatin solution containing 10 ml of a 5% aqueous solution. of sodium n-dodecylbenzenesulfonate. Then, after adding further water thereto to make the total volume 500 ml, the emulsion was applied to the support in a dry thickness of 5 microns.

2. Red-sensitive Emulsion Layer A red-sensitive silver iodobromide emulsion (containing 1 mol percent silver iodide) containing 5.5 X 10 mol of silver and 5.0 g of gelatin per g of the emulsion was coated on the cyan dye developer layer in a dry thickness of 3.5 microns.

3. Intermediate Layer 100 ml of a 5% aqueous gelatin solution containing 1.5 ml of a 5% aqueous solution of sodium n-dodecylbenzenesulfonate was coated on the redsensitive emulsion layer in a dry thickness of 1.5 microns.

4. Magenta Dye Developer-containing Layer 10 g of a magenta dye developer, 4-propoxy-2-p-( B hydroxyquinonylethyl)phenylazo-l-naphthol was dis solved in a mixture of 20 ml of N-n-butylacetanilide and 25 m1 of methylcyclohexanone and the solution was dispersed by emulsification in ml of a 10% aqueous gelatin solution containing 8 cc of a aqueous solution of sodium n-dodecylbenzenesulfonate. Then, after further adding water to make the total volume 400 ml, the resultant emulsion was coated on the intermediate layer in a dry thickness of 3.5 microns.

5. Green-sensitive Emulsion Layer A green-sensitive silver iodobromide emulsion (containing 2 mol percent silver iodide) containing 4.7 X mol of silver and 6.2 g and 6.2 g of gelatin per 100 g of the emulsion was coated on the magenta dye developer layer in a dry thickness of 1.8 microns.

6. Intermediate Layer 100 ml of a 5% aqueous gelatin solution containing 1.5 ml of a 5% aqueous solution of sodium n-dodecylbenzenesulfonate was coated on the greensensitive silver halide emulsion layer in a dry thickness of 1.0 microns.

7. Yellow Dye Developer Layer 10 g of a yellow dye developer, l-phenyl-3N-nhexylcarboxyamido-4-[p-( 2 ',5 '-dihydroxyphenethyl .phenylazo]-5-pyrazolone was dissolved under heating in a mixture of 10 ml of N-n-butylacetanilide and 25 ml of cyclohexanone and the solution prepared was dispersed by emulsification in 100 ml of a 10% aqueous gelatin solution containing 8 ml of a 5% aqueous solution of sodium n-dodecylbenzenesulfonate. After adding to the emulsion 5 m1 of a 2% aqueous solution of 2-hydroxy-4,6-dichloro-S triazine and further water to make the total volume 300 ml, the resultant emulsion was coated on the intermediate layer in a dry thickness of 1.5 microns.

8. Blue-sensitive Emulsion Layer A blue-sensitive silver iodobromide emulsion (containing 7 mol percent silver iodide) containing 3.5 X 10' mol of silver and 6.5 g of gelatin per 100 g of the emulsion was coated on the yellow dye developer layer in a dry thickness of 1.5 microns.

9. Protective Layer A 4% aqueous gelatin solution containing 2 ml of a 5% aqueous solution of sodium n-dodecylbenzenesulfonate and 5 ml of a 2% aqueous solution of mucochloric acid was coated on the blue-sensitive silver halide emulsion layer in a dry thickness of 1 micron.

Film 1 Film J was prepared in the same way as in the case of producing Film I except that a coating composition prepared by dissolving 2.08 g of 4-(t)-butylcatechol in a mixture of 10 ml oftri-o-cresyl phosphate and 10 ml of ethyl acetate, dispersing by emulsification the solution in 50 ml of a 10% aqueous gelatin solution, and then adding 50 g of the emulsion thus obtained in 100 ml of the coating composition for the protective layer as used in the case of producing Film I was coated as the protective layer in a dry thickness of 1 micron.

Film K Film K was prepared in the same way as in the case of producing Film 1 except that 5.40 g of the auxiliary developing agent of this invention was used in place of the 4(t)-butylcatechol in the coating composition for the protective layer.

Each of the Films I, J, and K thus prepared was gradationally exposed to white light and then a diffusion transfer development was conducted for one minute using the liquid processing composition and the imagereceiving element as used in Example I. The liquid processing composition was spread between both elements in an amount of 1.6 ml per 100 cm of the imagereceiving element. The reflective densities of the transferred color images were measured using a red filter, a green filter, and a blue filter respectively. The minimum density and the maximum density of the transferred color image are shown in the following tables.

As is shown in the above tables, it was confirmed that in Film K prepared using the auxiliary developing agent of this invention, the minimum density and the maximum density of the transferred color image were greatly improved.

Furthermore, when a photograph was taken in a camera using each of the color photographic films prepared in the same way as described above and the diffusion transfer development was conducted as in Example 1, the light anad darkness of the photographs obtained were indistinct and the contrast thereof was low in Films I and .I, while the light and darkness were distinct and the contrast was high in Film K. Also, in the case of using Film K, a color image having correct color rendering and less color mixing and color stains was obtained.

EXAMPLE 3 Film I as prepared in Example 2 was exposed graduationally and then subjected to a diffusion transfer development using each of the following liquid processing compositions containing the auxiliary developing agents shown below, respectively in the amounts shown in the same table and using the imagereceiving element shown below. The photosensitive element and the image-receiving element were allowed to stand in the superposed relationship and then the reflective densities of the transferred color image were measured from the image-receiving element side using a red filter, a green filter, and a blue filter respectively.

Liquid Processing Composition:

Water ml Potamium hydroxide l 1.2 g Carboxymethyl cellulose 3.4 g N-Benzyl-a-picolium bromide 15 g Benzotriazole 1.0 g Titanium dioxide 50.0 g

Auxiliary developing agent as shown below: Processing Composition Auxiliary Developing Agent Amount None 1 -Phenyl-3-pyrazolidone 4-Methylphenylhydroquinone 4-Methylcatechol Auxiliary Developing Agent of This Invention Auxiliary Developing Agent of This lnvention 'o'o'ob nomonve IMAGE-RECEIVING ELEMENT Processing Composition (a) Filter Minimum Density Maximum Density Blue 0.45 1.10 Green 0.45 1.26 Red 0.37 1.02

Processing Composition (b) Filter Minimum Density Maximum Density Blue 0.30 1.05 Green 0.38 11 1 Red 0.32 0.98

Processing Composition (c) Filter Minimum Density Maximum Density Blue 0.25 1.21 Green 0.26 1.30 Red 0.20 1.08

Processing Composition ((1) Filter Minimum Density Maximum Density Blue 0.28 1.10 Green 0.32 121 Red 0.25 0.98

Processing Composition (e) Filter Minimum Density Maximum Density Blue 0.23 1.20 Green 0.24 1.33 Red 0.19 1.1 1

Processing Composition (f) Filter Minimum Density MaximumDensity Blue 0.18 1.21 Green 0.1) l ,33 Red 0.18 1.10

As is shown in the above tables, in the case of using the liquid processing compositions containing the auxiliary developing agent of this invention, the color images obtained by the diffusion transfer process showed improved minimum density and maximum density and further showed quite less color mixing and color stains.

While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

What is claimed is:

1. A diffusion transfer color process comprising imagewise exposing a photosensitive element comprising a support having at least a silver halide emulsion layer and a dye developer associated with saidsilver halide in said silver halide emulsion layer and processing in the presence of 5,5,6,6'-tetrahydroxy-3,3,3',3'- tetramethyl-bis-l ,1 '-spirohydrindene as an auxiliary developing agent, which auxiliary developing agent is present in an alkaline processing solution permeable layer of said element during processing and is in reactive association with said silver halide, the exposed photosensitive element in a superposed relation with an image-receiving element with a liquid alkaline composition to immobilize the dye developer in the exposed areas of the silver halide emulsion layer and to transfer by diffusion the dye developer in the unexposed areas of the silver halide emulsion layer to the imagereceiving element.

2. The diffusion transfer color process as set forth in claim 1, in which the amount of said auxiliary developing agent is 0.01 to times the molar amount of said dye developer.

3. The diffusion transfer color process as set forth in claim 1, in which said dye developer is in a layer adjacent the silver halide emulsion layer associated there with.

4. The diffusion transfer color process as set forth in claim 1, in which said dye developer is in the silver halide emulsion layer associated therewith.

5. The diffusion transfer color process as set forth in claim 1, in which said auxiliary developing agent is in a silver halide emulsion layer of said photosensitive element.

6. The diffusion transfer color process as set forth in claim 1, in which said auxiliary developing agent is in a layer containing said dye developer, said layer being disposed adjacent the silver halide emulsion layer associated therewith.

7. The diffusion transfer color process as set forth in claim 1, in which said auxiliary developing agent is in an intermediate layer of said photosensitive element, which intermediate layer is between two silver halide emulsion layers of said element.

8. The diffusion transfer color process as set forth in claim 1, in which said auxiliary developing agent is in a protective layer of said image-receiving element, which protective layer is the uppermost layer on the side of said element which carries said at least one silver halide emulsion layer.

9. The diffusion transfer color process as set forth in claim 1, in which said auxiliary developing agent is in said liquid alkaline processing composition.

10. A diffusion transfer color process comprising imagewise exposing a multilayer color photographic element having coated on a support at least a red-sensitive silver halide emulsion layer, a cyan dye developercontaining layer adjacent said red-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer, a magenta dye developer-containing layer adjacent said green-sensitive silver halide emulsion layer, a blue-sensitive silver halide emulsion layer, and a yellow dye developer-containing layer adjacent said blue-sensitive silver halide emulsion layer and processing in the presence of 5,5',6,6'-tetrahydroxy-3,3,3,3- tetramethyl-bis-l ,l '-spirohydrindene as an auxiliary developing agent, which auxiliary developing agent is present in an alkaline processing solution permeable layer of said element during processing and is in reactive association with said silver halide, the exposed color photographic element in a superposed relation with an image-receiving element with a liquid alkaline composition to immobilize the dye developers in the exposed areas of said silver halide emulsion layers and transfer by diffusion the dye developers in the unexposed areas of the silver halide emulsion layers to the image-receiving element.

11. A color photographic element for the diffusion transfer color process having coated on a support at least one silver halide emulsion layer and a dye developer associated with the silver halide in said silver halide emulsion layer, said color photographic element containing ,5 ',6,6'-tetrahydroxy-3,3,3 ',3 tetramethyl-bis-l,1-spirohydrindene as an auxiliary developing agent in at least one photographic layer of said color photographic element.

12. The color photographic element for the diffusion transfer color process as set forth in claim 11, in which said auxiliary developing agent is in a silver halide emulsion layer of said element.

13. The color photographic element for the diffusion transfer color process as set forth in claim 11, in which said auxiliary developing agent is in a dye developercontaining layer adjacent the silver halide emulsion layer associated with said dye developer.

14. The color photographic element for the diffusion transfer color process as set forth in claim 11, in which said auxiliary developing agent is in an intermediate layer of said element, which intermediate layer is between two silver halide emulsion layers of said element.

15. The color photographic element for the diffusion transfer color process as set forth in claim 1 1, in which said auxiliary developing agent is in a protective layer of said element, which protective layer is the uppermost layer on the side of said element which carries said at least one silver halide emulsion layer.

16. The color photographic element for the diffusion transfer color process as set forth in claim 11, wherein said auxiliary developing agent is dissolved in a high boiling organic solvent and dispersed in said photographic layer.

Claims

1. A DIFFUSION TRANSFER COLOR PROCESS COMPRISING IMAGEWISE EXPOSING A PHOTOSENSATIVE ELEMENT COMPRISING A SUPPORT HAVING AT LEAST A SILVER HALIDE EMULSION LAYER AND A DYE DEVELOPER ASSOCIATED WITH SAID SILVER HALIDE IN SAID SILVER HALIDE EMULSION LAYER AND PROCESSING IN THE PRESENCE OF 5,5'' ,6,6''-TETRAHYDROXY3,3,3,'',3''- TETRAMATHYL-BIS- 1,1''-SPIRKOHYDRINDENCE AS AN AUXILIARY DEVELOPING AGENT, WHICH AUXILIARY DEVELOPING AGENT IS PRESENT IN AN ALKALINE PROCESSING SOLUTION PERMEABLE LAYER OF SAID ELEMENT DURING PROCESSING AND IS IN REACTIVE ASSOCIATION WITH SAID SILVER HALIDE, THE EXPOSED PHOTOSENTATIVE ELEMENT IN A SUPPORTED SILVER RELATION WITH AN IMAGE-RECEIVING ELEMENT WITH A LIQUID ALKALINE COMPOSITION TO IMMOBILIZE THE DYE SEVELOPER IN THE EXPOSED ARES OF THE SILVER HALIDE EMUNSON LAYER AND TO TRANSFER BY DIFFUSION THE DYE DEVELOPER IN THE UNEXPOSED AREAS OF THE SILVER HALIDE EMULSION LAYER TO THE IMAGE-RECEIVING ELEMENT.

2. The diffusion transfer color process as set forth in claim 1, in which the amount of said auxiliary developing agent is 0.01 to 10 times the molar amount of said dye developer.

3. The diffusion transfer color process as set forth in claim 1, in which said dye developer is in a layer adjacent the silver halide emulsion layer associated therewith.

10. A diffusion transfer color process comprising imagewise exposing a multilayer color photographic element having coated on a support at least a red-sensitive silver halide emulsion layer, a cyan dye developer-containing layer adjacent said red-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer, a magenta dye developer-containing layer adjacent said green-sensitive silver halide emulsion layer, a blue-sensitive silver halide emulsion layer, and a yellow dye developer-containing layer adjacent said blue-sensitive silver halide emulsion layer and processing in the presence of 5,5'',6, 6''-tetrahydroxy-3,3,3'',3''-tetramethyl-bis-1,1''-spirohydrindene as an auxiliary developing agent, which auxiliary developing agent is present in an alkaline processing solution permeable layer of said element during processing and is in reactive association with said silver halide, the exposed color photographic element in a superposed relation with an image-receiving element with a liquid alkaline composition to immobilize the dye developers in the exposed areas of said silver halide emulsion layers and transfer by diffusion the dye developers in the unexposed areas of the silver halide emulsion layers to the image-receiving element.

11. A color photographic element for the diffusion transfer color process having coated on a support at least one silver halide emulsion layer and a dye developer associated with the silver halide in said silver halide emUlsion layer, said color photographic element containing 5,5'',6,6''-tetrahydroxy-3,3,3'',3''-tetramethyl-bis-1,1''-spirohydrindene as an auxiliary developing agent in at least one photographic layer of said color photographic element.

13. The color photographic element for the diffusion transfer color process as set forth in claim 11, in which said auxiliary developing agent is in a dye developer-containing layer adjacent the silver halide emulsion layer associated with said dye developer.

15. The color photographic element for the diffusion transfer color process as set forth in claim 11, in which said auxiliary developing agent is in a protective layer of said element, which protective layer is the uppermost layer on the side of said element which carries said at least one silver halide emulsion layer.