JPS6212912B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to photographic elements for color diffusion transfer processes. When producing a multicolor transfer image using a dye image donor of the type that releases a diffusible dye as a result of a redox reaction of an oxidized developer produced by silver halide development with a dye-releasing redox compound, As described in Japanese Patent Publication No. 1983-33826, a photosensitive element having three combinations of a dye-releasing redox compound and an associated light-sensitive silver halide emulsion layer is used, and the dye of the dye-releasing redox compound is deposited on the image-receiving layer. The wavelength range of the absorbing portion in the dye-emitting redox compound must substantially correspond to the wavelength range of spectral sensitivity of the silver halide emulsion in combination with the dye-releasing redox compound. (The dye may be temporarily converted to short wavelength before the development process.) However, the oxidized product of the developer produced during silver halide development reacts with the dye-releasing redox compound, and the released dye is released into the adjacent silver halide. Suppression of development often occurs. This suppression phenomenon is particularly significant when the silver halide is a direct positive emulsion and is fogged and developed in the presence of a fogging agent. Although the reason for this is not clear, it is thought that the dye released by the reaction diffuses into the adjacent silver halide emulsion layer and inhibits development by adsorption or other means. It is an object of the present invention to provide a photographic element for color diffusion transfer processes in which there is substantially no reduction in maximum dye density (Dmax). It is an object of the present invention to provide a photographic element for color diffusion transfer with high sensitivity. In the photographic element of the present invention, the photographic performance of the light-sensitive material is significantly improved by providing a separating layer containing a hydrophilic colloid between the silver halide photographic emulsion layer and the dye-releasing redox compound-containing layer combined with the emulsion layer. It is based on what we have discovered. The present invention provides improved photographic performance in the above-described photographic element by providing a separating layer containing a solid pigment and a hydrophilic colloid between a silver halide photographic emulsion layer and a layer containing a dye-releasing redox compound associated with the emulsion layer. It is based on the findings that The above-mentioned object of the present invention is to form a silver halide photographic emulsion layer and a diffusible dye in combination with the emulsion layer as a result of a redox reaction with an oxidized form of a developer produced by development of silver halide by processing with an alkaline processing solution. A photographic element for color diffusion transfer comprising at least one layer (combination of) containing a dye-releasing redox compound capable of being released, comprising: a silver halide photographic emulsion layer; This is achieved by a photographic element for color diffusion transfer, which is characterized by providing a non-photosensitive isolation layer containing a hydrophilic colloid (hereinafter this layer will be simply referred to as "isolation layer") between the elements. . Preferably, the separator layer is a separator layer containing a solid pigment and a hydrophilic colloid. More specifically, at least an image-receiving layer, a light-shielding layer, a reflective layer, a red-sensitive silver halide emulsion layer, a cyan dye-releasing redox compound-containing layer, a color-mixing inhibitor-containing layer, and a green layer are formed on a transparent support in the following order. A photographic element containing at least a sensitive silver halide emulsion layer, a layer containing a magenta dye-releasing redox compound, a layer containing a color mixing inhibitor, a blue-sensitive silver halide emulsion layer, and a layer containing a yellow dye-releasing redox compound is processed with an alkaline processing solution. As a result, the oxidized form of the developer produced by silver halide development undergoes a redox reaction with the dye-releasing redox compound, resulting in an imagewise distribution of the diffusible dye, which diffuses into the image-receiving layer to form a color image. between a red-sensitive silver halide photographic emulsion layer and a layer containing a cyan dye-releasing redox compound, between a green-sensitive silver halide emulsion layer and a layer containing a magenta dye-releasing redox compound, or between a blue-sensitive halogen emulsion layer and a layer containing a magenta dye-releasing redox compound. A photograph for a color diffusion transfer method, characterized in that a layer containing gelatin as a main component is provided between at least one layer and a yellow dye-releasing redox compound-containing layer to separate these two layers. This is achieved through elements. In a preferred embodiment of the invention, a photographic element is used having the following multilayer structure (with each layer shown in order from top to bottom): Γ Protective layer Γ Blue-sensitive silver halide emulsion layer Γ Isolation layer Γ Diffusive layer Layer containing a yellow dye-releasing redox compound capable of releasing a yellow dye Γ Dye-releasing redox compound migration prevention layer Γ Diffusion-resistant layer containing a color mixing inhibitor (intermediate layer) Γ Green-sensitive silver halide emulsion layer Γ Isolation layer Γ Diffusion Layer containing a magenta dye-releasing redox compound capable of releasing a magenta dye Γ Dye-releasing redox compound migration prevention layer Γ Diffusion-resistant layer containing a color mixing inhibitor (intermediate layer) Γ Red-sensitive silver halide emulsion layer Γ Isolation layer Γ Diffusive A layer containing a cyan dye-releasing redox compound capable of releasing a cyan dye. A light-shielding layer containing a black pigment. A reflective layer containing a white pigment. A mordant layer containing a dye mordant. The dye-releasing redox compound migration prevention layer is a hydrophilic colloid. This is a layer whose main component is According to the invention, between the yellow dye-releasing redox compound-containing layer and the blue-sensitive silver halide emulsion layer, and between the magenta dye-releasing redox compound-containing layer and the green-sensitive silver halide emulsion layer, and the cyan dye-releasing redox compound-containing layer. By providing a separating layer between the red-sensitive silver halide emulsion layer and the red-sensitive silver halide emulsion layer, a decrease in maximum dye density (Dmax) can be significantly prevented. This effect is greater than when the silver halide is a direct positive emulsion and is developed without fogging in the presence of a fogging agent. One reason for this improved effect is that the presence of the isolation layer prevents inhibition of silver development of the silver halide emulsion by the dye released from the dye-releasing redox compound when the light-sensitive material is developed. At this time, if a solid pigment is included in the isolation layer, the effect will be greater. Since the inhibition of silver development of a silver halide emulsion by the released dye is large when developing a latent type direct positive emulsion, the effect of preventing silver development inhibition by the isolation layer is remarkable when a latent type direct positive emulsion is used. . Gelatin is particularly useful as a hydrophilic colloid for use in the isolation layer of the present invention. In addition to lime-processed gelatin, acid-processed gelatin, Bull.Soc.Sci.Phot.Japan,
Enzyme-treated gelatin as described in No. 16, p. 30 (1966) may be used, and gelatin hydrolysates and enzymatically decomposed products may also be used. As gelatin derivatives, various compounds such as acid halides, acid anhydrides, isocyanates, bromoacetic acids, alkanesultones, vinyl sulfonamides, maleimide compounds, polyalkylene oxides, and epoxy compounds can be added to gelatin. The product obtained by the reaction is used. Specific examples are US Patent No. 2614928, US Patent No. 3132945, and US Patent No. 3186846.
No. 3312553, British Patent No. 861414, No. 1033189
No. 1005784, Special Publication No. 1972-26845, etc. Examples of hydrophilic colloids other than gelatin include gelatin derivatives, graft polymers of gelatin and other polymers, proteins such as albumin and casein; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, and cellulose sulfate esters, sodium alginate, and starch derivatives. Sugar derivatives such as polyvinyl alcohol,
Polyvinyl alcohol partial acetal, poly-N
- A wide variety of synthetic hydrophilic polymeric materials can be used, such as single or copolymers of vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole, and the like. The gelatin graft polymer is a gelatin grafted with a single (homo) or copolymer of vinyl monomers such as acrylic acid, methacrylic acid, derivatives thereof such as esters and amides, acrylonitrile, styrene, etc. can be used. In particular, polymers with some degree of compatibility with gelatin, such as acrylic acid,
Graft polymers with polymers such as methacrylic acid, acrylamide, methacrylamide, hydroxyalkyl methacrylate are preferred. Examples of these are U.S. Pat.
It is described in issues such as No. 2956884. Typical synthetic hydrophilic polymer substances include West German Patent Application (OLS) No. 2312708 and U.S. Patent No. 3620751.
No. 3879205 and Special Publication No. 7561 of 1973. The separation layer containing hydrophilic colloid as a main component of the present invention may contain components such as a surfactant, a hardening agent, a thickening agent, and a matting agent as coating aids. The amount of hydrophilic colloid used in the isolation layer varies depending on the desired effect and the material used, but is 3 g/m ²
It is as follows. The thickness of the separator layer will vary depending on the desired effect and the materials used, but in the dry state it will be less than about 5 microns, preferably from about 0.05 microns to 3 microns. Examples of solid pigments used in the isolation layer of the present invention include white pigments such as titanium oxide, zinc oxide, zirconium oxide, lead white, and zinc sulfide, cadmium yellow, cobalt green, cobalt blue, cadmium red, gunjiyo, and indanthrone blue. , colored pigments such as phthalocyanine blue, and Special Publication No. 43-25644
Special Publication No. 48-3897, Special Publication No. 49-3824, Special Publication No. 11727, Special Publication No. 11727, Special Publication No. 11728, Special Publication No. 11728, Special Publication No. 1977-
No. 11729, Special Publication No. 49-49173, Special Publication No. 49-49174
Pearl pigments such as those disclosed in Japanese Patent Publication No. 51-6172 and Japanese Patent Publication No. 54-3406 can be used. Pearl pigments are usually coated with the above-mentioned white and/or colored pigments so that the core part on a thin plate has a thickness that has desirable optical properties. , but is not limited to materials. Particularly preferred pigments are titanium oxide, zirconium oxide and various pearlescent pigments. titanium oxide, zirconium oxide,
Various pearl pigments can be selected from commonly available brands, and particularly pearl pigments include Flamenco-Blue 100 and Flamenco from Mearl.
-Green100 and Flamenco-Red100 commercially available products can be used. More preferably, the pearl pigment has a thin core portion of the pigment, which is 1 μm or less, and is particularly preferably coated with a pigment on the core to a thickness that has favorable optical properties, and then coated with chemical and/or physical coating. It is desirable to have a pigment free of cores that have been removed by a conventional method. In addition, it has a sensitivity that is less than one tenth of the sensitivity of the emulsion in the silver halide emulsion layer, and the sensitivity, gradation, and gradation can be changed by development.
There are silver halide grains (preferably having a size of 0.2 μm or less) that do not substantially affect Dmax and Dmin. These solid pigments usually have a refractive index different from that of hydrophilic colloids by more than 0.1, so when exposed to light, reflection,
Due to scattering, interference phenomena, etc., light that has once passed through the silver halide emulsion layer passes through the silver halide emulsion layer again, thereby maintaining the secondary effect of increasing the sensitivity of the light-sensitive element. Preferably, a solid pigment is selected for the isolation layer between the blue-sensitive silver halide emulsion layer and the yellow dye-releasing redox compound-containing layer, so that only blue light is reflected and yellow light is transmitted. Preferably, solid pigments are selected for the isolation layer between the silver oxide emulsion layer and the layer containing the magenta dye-releasing redox compound to reflect only green light and transmit red light. The content of solid pigment varies depending on the desired effect and the materials used, but is 3 g/m ² or less (including 0 g/m ² ). Any of silver bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide and silver chloride may be used as silver halide in the photographic emulsion layer of the photographic light-sensitive material used in the present invention. The average grain size of the silver halide grains in the photographic emulsion (in the case of spherical or approximately spherical grains, the grain diameter is expressed, in the case of cubic grains, the ridge length is expressed as the grain size and the average based on the projected area) is not particularly restricted. is preferably 3μ or less. The particle size distribution may be narrow or wide. Silver halide grains in photographic emulsions may have regular crystal shapes such as cubes and octahedrons, or irregular crystal shapes such as spherical and plate shapes. or a composite of these crystal forms.
It may also consist of a mixture of particles of various crystalline forms. The silver halide grains may have different phases inside and on the surface, or may consist of a uniform phase.
Further, the particles may be particles in which the latent image is mainly formed on the surface, or may be particles in which the latent image is mainly formed inside the particle as described in US Pat. No. 2,592,550, US Pat. Photographic emulsions containing silver halide grains in which the latent image is formed primarily within the grains are preferred for the practice of this invention. As the core/shell type internal latent image type emulsion, the emulsion described in US Pat. No. 3,761,276 and the like can be used. The silver halide photographic emulsion used in the present invention is P.
Chimie et Physique by Glafkides
Photographique (Paul Montel, 1967),
Photographic Emulsion by GFDuffin
Chemistry (The Focal Press, 1966), V.
Making and Coating by L.Zelikman et al
Photographic Emulsion (published by The Focal Press)
(1964) and others. That is, any of the acidic method, neutral method, ammonia method, etc. may be used, and the method for reacting the soluble silver salt and soluble halogen salt may be any one-sided mixing method, simultaneous mixing method, or a combination thereof. . It is also possible to use a method in which particles are formed in an excess of silver ions (so-called back-mixing method).
As one type of simultaneous mixing method, a method in which the pAg in the liquid phase in which silver halide is produced can be kept constant, that is, a so-called controlled double jet method can also be used. According to this method, a silver halide emulsion with a regular crystal shape and a nearly uniform grain size can be obtained. Two or more types of silver halide emulsions formed separately may be mixed and used. In the process of silver halide grain formation or physical ripening, a cadmium salt, a zinc salt, a lead salt, a thallium salt, an iridium salt or a complex salt thereof, a rhodium salt or a complex salt thereof, an iron salt or an iron complex salt, etc. may be present. In the light-sensitive element of the present invention, the silver halide photographic emulsion emits relatively long-wavelength blue light using a sensitizing dye.
May be spectrally sensitized to green or red light. As sensitizing dyes, cyanine dyes, merocyanine dyes,
Complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, styryl dyes, hemicyanine dyes, oxonol dyes, hemioxonol dyes, etc. can be used. Useful sensitizing dyes for use in the present invention include, for example, U.S. Pat.
No. 3615643, No. 3615632, No. 3617293, No. 3615632, No. 3617293, No.
No. 3628964, No. 3703377, No. 3666480, No.
No. 3667960, No. 3679428, No. 3672897, No. 3679428, No. 3672897, No.
No. 3769026, No. 3556800, No. 3615613, No.
No. 3615638, No. 3615635, No. 3705809, No. 3615638, No. 3615635, No. 3705809, No.
No. 3632349, No. 3677765, No. 3770449, No. 3677765, No. 3770449, No.
No. 3770440, No. 3769025, No. 3745014, No.
No. 3713828, No. 3567458, No. 3625698, No. 3625698, No.
No. 2526632, No. 2503776, JP-A-48-76525,
It is described in Belgian Patent No. 691807, etc. A variety of photographic supports can be used in the photographic elements of this invention. In the photographic elements of this invention, the separating layer based on hydrophilic colloids, the layer containing color mixing inhibitors, the layer containing dye-releasing redox compounds, the photographic silver halide emulsion layer, and the other hydrophilic colloid layers can be formed using any suitable hardening layer. It can be cured with a film agent. These hardeners include aldehyde hardeners such as formaldehyde and mucohalogen acids, hardeners containing active halogens, dioxane derivatives, and oxypolysaccharides such as oxystarch. The layer containing the photographic silver halide emulsion may contain other additives, particularly those useful in photographic emulsions, such as lubricants,
Antifoggants, stabilizers, sensitizers, light-absorbing dyes,
Plasticizers and the like can be added. In the photographic element of the present invention, the isolating layer containing a hydrophilic colloid as a main component, the layer containing a color mixing inhibitor, the layer containing a dye-releasing redox compound, and other hydrophilic colloid layers are thickened according to the thickening method described in Japanese Patent Publication No. 3582-3582, etc. It is possible to contain an agent. Photographic elements of the present invention may include surfactants for various purposes. Depending on the purpose, any of nonionic, ionic, and amphoteric surfactants can be used, such as polyoxyalkylene derivatives, amphoteric amino acids (including sulfobetaines), and the like. Such surfactants are described in US Pat. No. 2,600,831;
US Patent No. 2271622, US Patent No. 2271623, US Patent No. 2275727, US Patent No. 2787604, US Patent No.
No. 2816920, US Patent No. 2739891 and Belgian Patent
Described in No. 652862. The color mixing prevention agent used in the present invention is patented in the United States.
No. 2336327, No. 2360290, No. 2403721, No. 2336327, No. 2360290, No. 2403721, No.
No. 3700453, No. 2701197, JP-A-46-2128, JP-A-54-29637, JP-A-53-9528, JP-A-55
-52056 etc. dihydroxybenzene derivatives and other dihydroxynaphthalene derivatives,
These include aminonaphthol derivatives, sulfonamide phenol derivatives, sulfonamide naphthol derivatives, and the like. These compounds must have a suitable ballast group in order to function usefully as a color mixing inhibitor. The amount of color mixture prevention agent applied is 1×10 ^-4 to 1×
10 ⁻² mole/m ² , preferably 5×10 ⁻⁴ to 5×
10 ^-3 mole/ ^m2 . The dye-releasing redox compounds used in the present invention contain a carrier component which, under alkaline conditions, as a function of oxidation (direct oxidation or cross-oxidation) provides a substance with a mobility different from that of the starting material. The dye image donors used in the present invention can be divided into two basic types, depending on the carrier used, as described below. (1) An initially diffusion-resistant compound, at least a portion of which is converted into a mobile or diffusible compound by the development action. (2) A compound that is initially mobile or diffusible and becomes immobile by being developed. Examples of (1) include JP-A-48-33826, JP-A-Sho.
49-126331, JP 51-104343, JP 53-
46730, JP 51-113624, JP 53-47823 Research Disclosure
Disclosure) Vol. 151 No. 15157 (published in November 1976), Vol. 130 No. 13024 (published in February 1975), and Vol. 156 No. 15654 (published in April 1977). Examples of (2) include JP-A-49-111624 and JP-A-51-63618. In the practice of the present invention, a dye-releasing redox compound represented by the following general formula () is preferred. Y-X () In the above formula, X represents a dye residue or a dye precursor residue bonded directly to Y or via an intervening group Z. Z represents an intervening group such as an alkylene group (or alkylidene group), an arylene group, or a heterocyclic group having 1 to 6 carbon atoms, and this intervening group Z is directly bonded to the X or -O- ,-S
−, −SO ₂ −, −NR ₀ − (R ₀ is a hydrogen atom or an alkyl group), −CO−, −CO−NH−, or −SO ₂ −
They are bonded via NH-. The dye residue can in principle be the residue of any type of dye. However, this dye residue must have sufficient diffusivity to pass through the photographic layer within the light-sensitive material and reach the image-receiving layer.
For this purpose, one or more water-solubility-imparting groups can be attached to the dye residue. Examples of suitable water-solubility-imparting groups include: carboxyl groups, sulfo groups, sulfonamido groups, sulfamoyl groups, aliphatic or aromatic hydroxyl groups, which sulfamoyl groups are capable of decomposing the dye image donor. The additional presence of other water-solubility-imparting groups is not necessarily necessary, since after the reaction has ended, the dye molecule can be endowed with a considerably greater diffusivity in the alkaline medium. Examples of dyes particularly suitable for the present invention include: azo dyes, azomethine dyes, anthraquinone dyes,
Phthalocyanine dyes, indigoid dyes, triphenylmethane dyes, metal complex dyes, colored metal complexes. The dye precursor residue refers to the release of auxochrome groups (i.e., auxochromes) within the color-forming system by oxidation during conventional or additional processing steps during photographic processing. The residue of a compound that can be converted into a dye by liberating a chromophore and joining it to a chromophore. The dye precursor in this case may be a leuco dye,
Alternatively, it may be a dye that is converted to another dye during photographic processing. Y is the result of development under alkaline conditions,
Represents a component that provides a dye compound having diffusivity different from that of the dye image donor represented by formula (). Y useful in compounds of formula () is an N-substituted sulfamoyl group. For example, Y can include a group represented by the following formula (A). In the formula, β represents a corner group of a nonmetallic atom necessary to form a benzene ring, and a carbocycle or a heterocycle is fused to the benzene ring to form, for example, a naphthalene ring, a quinoline ring, or a 5,6,7,8-tetrahydro ring. A naphthalene ring, a coumaron ring, etc. may also be formed. Furthermore, the benzene ring or the ring formed by condensing a carbocycle or heterocycle with the benzene ring includes a halogen atom, an alkyl group, an alkoxy group, an aryl group,
It may be substituted with an aryloxy group, a nitro group, an amino group, an alkylamino group, an arylamino group, an amide group, a cyano group, an alkylmercapto group, a keto group, a carbalkoxy group, a heterocyclic group, or the like. α represents a group represented by -OG ¹ or -NHG ² . Here, G ¹ represents a hydrogen atom or a group that produces a hydroxyl group when hydrolyzed, preferably a hydrogen atom,

[Formula] or

It is a group represented by [Formula]. Here, G ³ is an alkyl group, particularly an alkyl group having 1 to 18 carbon atoms such as a methyl group, ethyl group, or propyl group, or a halogen-substituted alkyl group having 1 to 18 carbon atoms such as a chloromethyl group or a trifluoromethyl group;
Represents a phenyl group or a substituted phenyl group. Also, G ²
represents a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, or a hydrolyzable group. Here, preferred hydrolyzable groups for G ² are:

[Formula] A group represented by -SO ₂ G ⁵ or -SOG ⁵ . Here, G ⁴ is an alkyl group having 1 to 4 carbon atoms such as a methyl group; a halogen-substituted alkyl group such as a mono-, di- or trichloromethyl group or a trifluoromethyl group; an alkylcarbonyl group such as an acetyl group; an alkyloxy group; Substituted phenyl groups such as nitrophenyl groups and cyanophenyl groups; phenyloxy groups substituted or unsubstituted with lower alkyl groups or halogen atoms; carboxyl groups;
Represents an alkyloxycarbonyl group; an aryloxycarbonyl group; an alkylsulfonyl ethoxy group or an arylsulfonyl ethoxy group. Also G ⁵
represents a substituted or unsubstituted alkyl group or aryl group. Furthermore, b is an integer of 0, 1 or 2. However, in the above α, an alkyl group that makes the compound represented by the general formula (A) immobile and non-diffusible as G ₂ of -NHG ₂ may be introduced. , except in that case, i.e., α is −
When it is a group represented by OG ¹ , and when α is represented by -NHG ₂ and G ₂ is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a hydrolyzable group, b is 1 or 2, Preferably it is 1. Ball represents a ballast group. The ballast group will be explained in detail later. Specific examples of this type of Y are described in JP-A-48-33826 and JP-A-53-50736. Another example of Y suitable for this type of compound is a group represented by the following formula (B). In the formula, Ball, α, and b have the same meanings as in formula (A), and β' represents an atomic group necessary to form a carbocyclic ring, for example, a benzene ring, and a carbocyclic or heterocyclic ring is added to the benzene ring. The rings may be fused to form a naphthalene ring, a quinoline ring, a 5,6,7,8-tetrahydronaphthalene ring, a chroman ring, or the like.
Furthermore, halogen atoms, alkyl groups,
alkoxy group, aryl group, aryloxy group,
A nitro group, an amino group, an alkylamino group, an arylamino group, an amide group, a cyano group, an alkylmercapto group, a keto group, a carbalkoxy group, a heterocyclic group, etc. may be substituted. Specific examples of this type of Y are disclosed in JP-A-51-113624 and U.S. Patent No. 4,053,312.
It is described in. Furthermore, another example of Y suitable for this type of compound is a group represented by the following formula (C). In the formula, Ball, a, and b have the same meanings as in formula (A), and β'' represents an atomic group necessary to form a heterocycle, such as a pyrazole ring or a pyridine ring,
A carbocycle or a heterocycle may be further fused to the heterocycle, and the above various rings may be further fused with formula (B).
The ring may be substituted with the same type of substituent as the substituent described in . A specific example of this type of Y is described in JP-A-51-104343. Furthermore, Y that is effective for this type of compound is represented by formula (D). In the formula, γ preferably represents a hydrogen atom, a substituted or unsubstituted alkyl group, an aryl group or a heterocyclic group, or -CO- ^G6 ; ^G6 is ^-OG7 , -S- ^G7 or

[Formula], (G ⁷ represents hydrogen, an alkyl group, a cycloalkyl group, or an aryl group, and the alkyl group, cycloalkyl group, and aryl group may have a substituent, and G ⁸ is G represents the same group as the ⁷ group, or G ⁸ represents an acyl group derived from an aliphatic or aromatic carboxylic acid or sulfonic acid, G ⁹ represents hydrogen or an unsubstituted or substituted alkyl group); δ is , represents the residues necessary to complete the fused benzene ring,
The fused benzene ring may therefore carry one or more substituents; and the substituents on said fused benzene ring completed by γ and/or δ are or contain a ballast group. It includes. A specific example of this type of Y is published in JP-A-Sho.
51-104343 and 53-46730. Furthermore, examples of Y suitable for this type of compound include a group represented by formula (E). In the formula, Ball has the same meaning as in formula (A), and ε is an oxygen atom or a =NG'' group (G'' represents a hydroxyl group or an amino group which may have a substituent), and especially when ε is = In the case of the NG'' group, G'' is typically G'' in the =C=N-G'' group formed as a result of the dehydration reaction of a carbonyl reagent H ₂ N-G'' with a ketone group; Examples of H ₂ N-G" compounds include hydroxylamine, hydrazines, semicarbazides, thiosemicarbazides, etc. Specifically, hydrazines include hydrazine, phenylhydrazine, or an alkyl group or alkoxy group on the phenyl group. Substituted phenylhydrazine having a substituent such as a group, a carbalkoxy group, or a halogen atom, as well as isonicotinic acid hydrazine and the like can be mentioned. Examples of semicarbazides include phenyl semicarbazide or substituted phenyl semicarbazides having substituents such as alkyl groups, alkoxy groups, carbalkoxy groups, and halogen atoms, and thiosemicarbazides include various derivatives similar to semicarbazide. can be given. In addition, β in the formula is a 5-, 6-, or 7-membered saturated or unsaturated non-aromatic hydrocarbon ring, specifically, for example, cyclopentane, cyclohexanone, cyclohexenone, cyclopentenone, cyclo Typical examples include heptanone and cycloheptenone. Furthermore, the 5- to 7-membered non-aromatic hydrocarbon ring may be fused with another ring at an appropriate position to form a condensed ring. Here, the other rings may be various rings, regardless of whether they exhibit aromaticity or not, and regardless of whether they are hydrocarbon rings or heterocycles, but when forming a condensed ring, For example, in the present invention, a fused ring formed by fusing benzene with the above-mentioned 5- to 7-membered aromatic hydrocarbon ring, such as indanone, benzcyclohexenone, benzcycloheptenone, etc., is more preferred in the present invention. The 5- to 7-membered aromatic hydrocarbon ring or the fused ring is an alkyl group, an aryl group, an alkyloxy group, an aryloxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, a halogen atom, It may have one or more substituents such as a nitro group, an amino group, an alkylamino group, an arylamino group, an amide group, an alkylamido group, an arylamido group, a cyano group, an alkylmercapto group, and an alkyloxycarbonyl group. G ¹⁰ represents a hydrogen atom or a halogen atom such as fluorine, chlorine, or bromine. A specific example of this type of Y is described in JP-A-53-3819. In addition, examples of Y in the compound of the present invention include, for example, JP-B No. 48-32129, JP-A No. 48-39165, JP-A No. 49-Sho.
64436 and US Pat. No. 3,443,943. Another type of compound represented by formula () releases a diffusible dye by self-ring closure under alkaline conditions, but when it reacts with an oxidized developer, it does not substantially release the dye. Examples include diffusion-resistant dye image donors. Y that is effective for this type of compound includes, for example, the formula
The things listed in (F) can be mentioned. In the formula, α' is an oxidizable nucleophilic group such as a hydroxyl group, a primary or secondary amino group, a hydroxyamino group, a sulfonamide group, or a precursor thereof, and is preferably a hydroxyl group. α″ is a dialkylamino group or any group defined for α′, preferably a hydroxyl group. G ¹⁴ is an electrophilic group such as -CO- or -CS-, preferably - CO- ^.G15 is an oxygen atom, sulfur atom, selenium atom, nitrogen atom, etc. If it is a nitrogen atom, it is a hydrogen atom, a carbon atom 1
Alkyl groups or substituted alkyl groups containing up to 10 carbon atoms may be substituted with aromatic residues containing 6 to 20 carbon atoms. Preferred G ¹⁵ is an oxygen atom. G ¹³ is an alkylene group having 1 to 3 carbon atoms, and a represents 0 or 1, preferably 0. G ¹³ is a substituted or unsubstituted alkyl group containing 1 to 40 carbon atoms, or 6 carbon atoms
-40 substituted or unsubstituted aryl groups, preferably alkyl groups. G ¹⁶ , G ¹⁷ and G ¹⁸ are each a hydrogen atom, a halogen atom, a carbonyl group, a sulfamyl group, a sulfonamide group, an alkyloxy group containing 1 to 40 carbon atoms, or
It has the same meaning as G ¹³ , and G ¹⁶ and G ¹⁷ may together form a 5- to 7-membered ring. Also G ¹⁷ is

[Formula] may be used. However, at least one of G ¹³ , G ¹⁶ , G ¹⁷ and G ¹⁸ represents a ballast group. A specific example of this type of Y is described in JP-A-51-63618. Further examples of Y suitable for this type of compound include the group represented by (G). In the formula, Ball and β′ are the same as those in formula (B), and G ¹⁹ is an alkyl group (including substituted alkyl groups)
It is. For specific examples of this type of Y, see JP-A-53-
It is described in 35533. Further, as Y suitable for this type of compound, the formula (H)
There is a group represented by In the formula, Ball and β′ are the same as those in formula (B), and G ¹⁹ is the same as that in formula (G). This kind of Y
For specific examples, see JP-A No. 49-111628 and
It is described in 52-4819. The ballast group is an organic ballast group that can make the dye image donor diffusion resistant even during development in alkaline processing solutions, and has 8 carbon atoms.
A group containing a hydrophobic group of up to 32 is preferred. Such an organic ballast group is attached to the dye image donor directly or as a linking group (e.g., imino bond, ether bond, thioether bond, carbonamide bond, sulfonamide bond, ureido bond, ester bond, imide bond, carbamoyl bond, sulfamoyl bond, etc.). alone or in combination). Some specific examples of the ballast group are described below. Alkyl and alkenyl groups (e.g. dodecyl group, octadecyl group), alkoxyalkyl groups (e.g. 3-(octyloxy)propyl group as described in Japanese Patent Publication No. 39-27563, 3-(2-
ethylundecyloxy)propyl group), alkylaryl group (e.g. 4-nonylphenyl group,
2,4-di-tert-butylphenyl group), alkylaryloxyalkyl group (e.g., 2,4-di-tert-butylphenyl group),
tert-pentylphenoxymethyl group, α(2.4
-di-tert-pentylphenoxy)propyl group,
1-(3-pentadecylphenoxy)-ethyl group,
etc.), acylamidoalkyl groups, (e.g. U.S. patents
Groups such as those described in 3337344 and 3418129, 2-(N-butylhexadecaneamide)
ethyl group, etc.), alkoxyaryl and aryloxyaryl groups (e.g., 4-(n-octadecyloxy)phenyl group, 4-(4-n-dodecylphenyloxy)phenyl group, etc.), alkyl or alkenyl groups Residues that have both a chain aliphatic group and a water-solubilizing group such as a carboxyl or sulfo group (for example, 1-carboxymethyl-2-
nonanedecenyl group, 1-sulfoheptadecyl group,
), alkyl groups substituted with ester groups (e.g., 1-ethoxycarbonylheptadecyl group, 2
-(n-dodecyloxycarbonyl)ethyl group,
etc.), an alkyl group substituted with an aryl group or a heterocyclic group (e.g., 2-[4-(3-methoxycarbonyluneicosanamido)phenyl]ethyl group, 2-[4-(2-n-octadecylsuccinimide)) phenyl]ethyl group, etc.), and an aryl group substituted with an aryloxyalkoxycarbonyl group (e.g., 4-[2-2,4-di-
tert-pentylphenyloxy)-2-methylpropyloxycarbonyl]phenyl group, etc.). Particularly preferred among the above organic ballast groups are those bonded to a linking group as represented by the following general formula. -CONH-R ¹ -O-R ³ () -O-R ⁴ () -CONHR ³ () Here, R ¹ is an alkylene group having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, such as propylene ^R2 represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, such as a tert-amyl group, and n
represents an integer from 1 to 5 (preferably 1 or 2). R ³ has 4 to 30 carbon atoms, preferably 10 to 30 carbon atoms.
It represents up to 20 alkyl groups, such as dodecyl, tetradodecyl, hexadecyl. R ⁴ is an alkyl group having 8 to 30 carbon atoms, preferably 10 to 20 carbon atoms (for example, hexadecyl group, octadecyl group, etc.) or a substituted alkyl group having 8 or more carbon atoms in total (the alkyl residue has 1 or more carbon atoms. As a substituent is, for example, a carbamoyl group. A particularly useful group as Y in the above compounds is an N-substituted sulfamoyl group. Examples of N-carbocyclic substituted sulfamoyl groups in which the N-substituent of the N-substituted sulfamoyl group is preferably a carbocyclic group or a heterocyclic group include those represented by formulas (A) and (B). Particularly preferred. Among the above examples of the N-heterocycle-substituted sulfamoyl group, the formula
Particularly preferred are those represented by (C) and (D). Specific examples of dye-releasing redox compounds include, for example, in addition to the compounds described in the Examples of the present invention. etc. The amount of dye-releasing redox compound applied was 1×
10 ⁻⁴ ~1×10 ⁻² mole/m ² , preferably 2×10 ⁻⁴ ~
It is 2×10 ^-3 mole/m ² . The dye-releasing redox compound used in the present invention can be dispersed in a hydrophilic colloid carrier by various methods depending on the type of compound. For example, a compound having a dissociable group such as a sulfo group or a carboxyl group can be dissolved in water or an alkaline aqueous solution and then added to the hydrophilic colloid solution. A solution obtained by dissolving a dye-releasing redox compound that is difficult to dissolve in an aqueous medium and easily soluble in an organic solvent in an organic solvent is added to a hydrophilic colloid solution and dispersed into fine particles by stirring or the like. Suitable solutions include methyl acetate, tetrahydrofuran, methyl ethyl ketone, cyclohexanone, β-butoxy-β-ethoxyethyl acetate, dimethylformamide, dimethyl sulfoxide, 2-
Examples include methoxyethanol and tri-n-butyl phthalate. Among these dispersion solvents, those with relatively low vapor pressures are evaporated during drying of the photographic layer, or
It can also be volatilized by the method described in US Pat. No. 2,322,027; US Pat. No. 2,801,171 before application. Among these dispersion solvents, those that are easily soluble in water can be removed by a water washing method as described in US Pat. No. 2,949,360 and US Pat. No. 3,396,027. In order to stabilize the dispersion of the dye-releasing redox compound and to facilitate the dye-forming process, a solvent that is substantially insoluble in water and having a boiling point above 200° C. at normal pressure may be incorporated with the dye-releasing redox compound in the photographic element. It's advantageous. High boiling point solvents suitable for this purpose include triglycerides of higher fatty acids, di-
Aliphatic esters such as octyl adipate, phthalic esters such as C-n-butyl phthalate, phosphoric esters such as tri-o-cresyl phosphate, tri-n-hexyl phosphate, N.N. -Amides such as diethyl laurylamide, hydroxy compounds such as 2,4-di-n-aminophenol, and the like. Additionally, it is advantageous to incorporate a philic polymer with the dye-releasing redox compound in the photographic element to stabilize the dispersion of the dye-releasing redox compound and to facilitate the dye image formation process. Philic polymers suitable for this purpose include: sierrac; phenol-formaldehyde condensates; poly-n-butyl acrylate; copolymers of n-butyl acrylate and acrylic acid; copolymers of n-butyl acrylate, styrene and methacramide; etc. These polymers may be dissolved in an organic solution together with a dye-releasing redox compound and then dispersed in a hydrophilic colloid. Hydrosols may also be added. Dispersion of dye-releasing redox compounds is generally effectively achieved under high shear forces. For example, a high-speed rotating mixer, a colloid mill, a high-pressure milk homogenizer, the high-pressure homogenizer disclosed in British Patent No. 1304264, an ultrasonic emulsifier, etc. are useful.
Dispersion of the dye-releasing redox compound is greatly aided by the use of surfactants as emulsifying aids. Surfactants useful in dispersing the dye-releasing redox compounds used in the present invention include sodium triisopropylnaphthalene sulfonate, sodium dinonylnaphthalene sulfonate, p-
There are anionic surfactants known in Japanese Patent Publication No. 39-4293, such as sodium dodecylbenzenesulfonate, dioctyl sulfosuccinate sodium salt, sodium cetyl sulfate, and these anionic surfactants and higher fatty acids of anhydrohexitol. The combination with esters shows particularly good emulsifying ability, as known from US Pat. No. 3,676,141. The color mixing inhibitor used in the present invention can be dispersed in exactly the same manner as the dye-releasing redox compound described above. Examples of methods for obtaining color diffusion transfer images using dye-releasing redox compounds include the following processes. (A) Imagewise exposing a photographic element comprising a support having at least one light-sensitive silver halide emulsion layer in combination with a dye-releasing redox compound. (B) Spreading an alkaline processing composition on the photosensitive silver halide emulsion layer and developing each photosensitive silver halide in the presence of a silver halide developer. (C) The resulting oxidized developer, depending on the amount of exposure, cross-oxidizes the dye-releasing redox compound. (D) Cleaving the oxidized form of the dye-releasing redox compound to release a diffusible dye. (E) Imagewise diffusion of the released dye to form a transferred image on the image-receiving layer (in direct or indirect contact with the photosensitive layer). Any silver halide developer can be used in the above process as long as it is capable of cross-oxidizing the dye-releasing redox compound. Such developing agents may be included in the alkaline processing composition or in appropriate layers of the photographic element. Examples of developing agents that can be used in the present invention are as follows. Hydroquinones, amylphenols (e.g. N-methylaminophenol), pyrazolidones (e.g. phenidone, 1-phenyl-3-pyrazolidone), dimezone (1-phenyl-4.4
-dimethyl-3-pyrazolidone), 1-phenyl-4-methyl-4-oxymethyl-3-pyrazolidone), phenylenediamines (e.g. N/N-
Diethyl-p-phenylenediamine, 3-methyl-N.N-diethyl-p-phenylenediamine,
3-methoxy-N-ethoxy-p-phenylenediamine) and the like. Of those listed herein, black and white developers are particularly preferred as they generally have properties that reduce stain formation in the image receiving layer more than color developers such as phenylene diamines. Examples of fogging agents that can be used in the present invention include US Pat. No. 2,588,982, US Pat.
No. 3615615, No. 4030925, No. 4031127,
Those described in No. 3718470 and No. 4266013 are used. The alkaline processing composition may also contain compounds that promote development or dye diffusion, such as benzyl alcohol. As for the image-receiving layer, neutralizing layer, neutralization rate controlling layer (timing layer), processing composition, etc. that can be used in the photographic element of the present invention, those described in JP-A-52-64533 can be applied. When the photographic element of the invention is in the form of a photographic film unit, that is, after imagewise exposure, it can be photographically processed by passing the film unit between a pair of juxtaposed pressure members. The film is composed of
Preferably, it is a unit. The most recommended type of film for applying the present invention is a layered and integrated type.
An embodiment of the unit is disclosed in Belgian patent no. 757959. According to this embodiment, an image-receiving layer, a substantially opaque light-reflecting layer (for example, _two TiO layers and a carbon black layer), and one or more of the photosensitive layers described above are sequentially coated on a transparent support. This is further layered with a transparent cover sheet face-to-face. A rupturable container containing an alkaline processing composition containing an opacifying agent (e.g. carbon black) for blocking light is placed adjacent the top layer (protective layer) of the photosensitive layer and the transparent cover sheet. Such a film unit is exposed to light through a transparent cover sheet, and upon removal from the camera, the container is ruptured by a pressing member, and the processing composition (including the opacifying agent) is transferred to the photosensitive layer and the cover sheet. It will be spread out over one area in between. Thereby, the photosensitive element is shielded from light in the form of a sandwich, and development proceeds in the light. The film unit of these embodiments includes:
In either case, it is recommended to incorporate a neutralization mechanism as mentioned above. Among these, it is preferable to provide a neutralizing layer on the cover sheet (if desired, further provide a timing layer on the side where the processing liquid is spread). Another useful lamination configuration in which photographic elements having the layer configuration of the present invention can be used is:
U.S. Patent No. 3415644, U.S. Patent No. 3415645, U.S. Patent No. 3415646
Nos. 3,647,487 and 3,635,707, and West German Patent Application (OLS) No. 2,426,980. Example 1 A photosensitive element according to the invention was made by coating the following layers in the order listed on a transparent polyethylene terephthalyl film support. (1) Copoly [styrene-N-vinylbenzyl-
An image-receiving layer containing 4.0 g/m ² of N.N.N-trihexylammonium chloride and 4.0 g/m ² of gelatin. (2) Titanium dioxide 22g/m ² and gelatin 2.2g/m ²
Contains a white reflective layer. (3) Carbon black 2.7g/m ² and gelatin 2.7
Opaque layer containing g/m ² . (4) Cyan dye-releasing redox compound with the following structure
0.50g/m ² , N・N-diethyl laurylamide
A layer containing 0.50 g/m ² and gelatin 1.5 g/m ² . (5) Titanium dioxide 0.3g/ ^m2 and gelatin 0.68g/
Isolation layer containing m ² . (6) Red-sensitive internal latent image type direct positive emulsion (gelatin
1.1g/m ² , silver 1.4g/m ² ) and 1-acetyl-2
-[4-(2,4-di-t-pentylphenoxyacetamido)phenyl]-hydrazine (0.015
g/m ² ) and 2-pentadecylhydroquinone
A layer containing sodium 5-sulfonate (10.067 g/m ² ). (7) Gelatin (1.0g/m ² ) and 2,5-di-t-
Mixing inhibitor-containing layer containing pentadecyl hydroquinone (1.0 g/m ² ) and tricresyl phosphate (0.5 g/m ² ). (8) Dye-releasing redox compound migration prevention layer containing gelatin (0.5 g/m ² ). (9) A magenta dye-releasing redox compound with the following structure (0.80 g/m ² ), N.N-diethyl laurylamide (0.20 g/m ² ) and gelatin (1.2 g/m 2 ).
m ² ). (10) Titanium dioxide 0.15g/ ^m2 and gelatin 0.70g/
Isolation layer containing m ² . (11) Green-sensitive internal immersion type silver iodobromide emulsion (gelatin
1.1g/m ² , silver 1.4g/m ² ) and 1-acetyl-2
-[4-(2,4-di-t-pentylphenoxyacetamido)phenyl]-hydrazine (0.015
g/m ² ) and 2-pentadecylhydroquinone
A layer containing sodium 5-sulfonate (0.067 g/m ² ). (12) Gelatin (1.0g/m ² ) and 2,5-di-t-
Color mixing inhibitor containing layer containing pentadecyl hydroquinone (1.0 g/m ² ) and tricresyl phosphate (0.5 g/m ² ). (13) Dye-releasing redox compound migration prevention layer containing gelatin (0.5 g/m ² ). (14) Yellow dye-releasing redox compound with the following structure (1.0 g/m ² ), N·N-diethyl laurylamide (0.25 g/m ² ), gelatin (1.0 g/m ² )
layer containing. (15) Titanium dioxide 0.15g/ ^m2 and gelatin 0.43
Isolation layer containing g/m ² . (16) Blue-sensitive internal latent image type direct positive silver iodobromide emulsion (gelatin 1.1 g/m ² , silver 1.4 g/m ² ) and 1-acetyl-2-[4-(2,4-di-t- pentylphenoxyacetamido)phenyl]-hydrazine 10.015g/m ² ) and 2-pentadecylhydroquinone 5-sodium sulfonate 0.067g/
m ² ). (17) Gelatin 1.3g/m ² , polyethyl acrylate latex 0.9g/m ² , Tinuvin 0.5g/m 2
m ² , a protective layer containing the hardener triacryloylperhydrotriazine 0.026 g/m ² . As a comparative sample for photographic elements of the present invention,
A comparative photographic element () was made that was identical to photographic element () except that isolation layers (5), (10), and (15) were removed from photographic element (). A photographic element () was also made which was exactly the same as the photographic element (5), (10), and (15) except that the solid pigment was removed. A cover sheet was made by coating the following layers in the order listed on a transparent polyethylene terephthalate film support. (1) Neutralization layer consisting of polyacrylic acid (10g/m ² ). (2) Timing layer consisting of acetylcellulose (10g/m ² ). Using 2854〓 tungsten light for each photographic element,
Exposure was performed through an optical wedge with a density difference of 0.2 (maximum exposure at this time was 10 C.MS). The processing solution was uniformly spread between each exposed photographic element and the above-mentioned cover sheet by passing the viscous processing solution shown below in a bag-like container between a pair of juxtaposed compression rollers. Composition of viscous treatment liquid Water 820c.c. 1N-H ₂ SO ₄ 5c.c. Hydroxyethyl cellulose 60g 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone 5g 5-methylbenzotriazole 2g t-butylhydroquinone 0.4g Sodium sulfite 2g Carbon black 150g Sodium hydroxide 30g The concentration was measured 1 hour after the treatment solution was developed and shown in Table 1 below.
The results were obtained. The photographic image is a positive image.

【table】

[Table] Table 1 shows that the photographic elements () and () having the isolation layer of the present invention have a remarkable increase in yellow density, magenta density, and cyan density compared to the photographic element (). It can be seen that the is large. Reference Example In the photographic element of Example 1, the internal latent image type direct positive silver halide emulsion was replaced with a surface latent image type negative emulsion, and 1-acetyl-2-[4-(2,4-di-t-
pentylphenoxyacetamido)phenyl]-
A photographic element (corresponding to the photographic element) and a photographic element (corresponding to the photographic element) were prepared by removing hydrazine (fogging agent) from the photographic element, exposed and processed in the same manner as in Example 1, and the density was measured. Two tables were obtained. A photographic image is a negative image.

[Table] From Table 2, it can be seen that there is almost no difference between the photographic elements and the photographic elements. Therefore, it is clear that the isolation layer of the present invention has no effect when a surface latent image type negative emulsion is used. Preferred embodiments of the present invention are listed below. (1) At least an image-receiving layer, a light-shielding layer, a reflective layer, a red-sensitive silver halide emulsion layer, a cyan dye-releasing redox compound-containing layer, a color-mixing inhibitor-containing layer, and a green-sensitive halogen layer are formed on a transparent support in the following order. Processing a photographic element containing at least a silver oxide emulsion layer, a layer containing a magenta dye-releasing redox compound, a layer containing a color mixing inhibitor, a blue-sensitive silver halide emulsion layer, and a layer containing a yellow dye-releasing redox compound with an alkaline processing solution. As a result of the redox reaction of the oxidized form of the developer produced by silver halide development with the dye-releasing redox compound, an imagewise distribution of the diffusible dye occurs, and this dye diffuses into the image-receiving layer to form a color image. In a photographic element, between the silver halide photographic emulsion layer and a layer containing a cyan dye-releasing redox compound, between the green-sensitive silver halide emulsion layer and a layer containing a magenta dye-releasing redox compound, or between the blue-sensitive silver halide emulsion layer. and the yellow dye-releasing redox compound-containing layer;
1. A photographic element for color diffusion transfer, characterized in that it is provided with a gelatin-based layer for separating the two layers. (2) A photographic element for color diffusion transfer according to embodiment (1), wherein the silver halide emulsion layer is in the opposite direction from the image-receiving layer with respect to the dye-releasing redox compound-containing layer. (3) Embodiment (2), characterized in that a solid pigment is contained in the isolation layer, the main component of which is gelatin, provided between the silver halide photographic emulsion layer and the dye-releasing redox compound-containing layer combined with the emulsion layer. Photographic elements for color diffusion transfer methods. (4) The photographic element for color diffusion transfer method according to embodiment (3), characterized in that a fogging agent is contained in the alkaline processing liquid or in the photosensitive element. (5) The photographic element for color diffusion transfer method according to embodiment (3), wherein the silver halide emulsion contained in the silver halide emulsion layer is a core/shell type internal latent image type emulsion. (6) A photographic element for color diffusion transfer according to embodiment (5), characterized in that the silver halide emulsion in the silver halide emulsion layer is a direct positive emulsion. (7) A photographic element for color diffusion transfer method, characterized in that it is subjected to fogging development according to embodiment (6).

Claims (1)

[Claims] 1 Direct positive silver halide photographic emulsion layer and the emulsion layer combined with the emulsion layer, which releases a diffusible dye as a result of a redox reaction with the oxidized form of the developer produced by development of the silver halide when treated with an alkaline processing solution. A photographic element for color diffusion transfer comprising at least one dye-releasing redox compound-containing layer, wherein a non-light-sensitive, , a photographic element for color diffusion transfer, characterized in that it is provided with a separating layer containing a hydrophilic colloid.