JPS5933898B2 - photo elements - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to color diffusion transfer photography, and more particularly to a novel neutralization timing layer for use in color diffusion transfer photography (DTR color).

It is well known that a neutralizing layer is used in DTR color photosensitive materials for purposes such as stopping development and stabilizing images. Furthermore, it is well known to provide a neutralization timing layer to prevent premature neutralization by the neutralization layer.
The various timing layers are
Sure” Research Disclosure Magazine Taki 12331
(Vol. 123, July 1974). In particular, US Pat. No. 3,753,764 describes the use of acetylcellulose for the timing layer. However, when acetylcellulose is used in the timing layer, its stability over time deteriorates, especially at high temperatures and high humidity, and acetylcellulose becomes difficult to be hydrolyzed by alkaline, which increases the neutralization timing time and causes defects such as increased maximum and minimum concentrations. This is pointed out in US Pat. No. 4,029,849. In order to overcome these drawbacks, the above-mentioned US Pat. No. 4,029,849 describes the combined use of acetyl cellulose and maleic anhydride copolymer. However, even when poly(styrene-co-maleic anhydride), which is a maleic anhydride copolymer described in the US patent, is used in combination with acetylcellulose, the storage stability is still insufficient, and further improvements are desired. . Furthermore, the maleic anhydride copolymer does not have sufficient compatibility with acetyl cellulose, resulting in low stability of the coating solution and low transparency of the coating film. In a pool unit in which a photosensitive material is exposed to light through a coating film of a timing layer, if the coating film is opaque, this results in a decrease in sensitivity and resolution.

SUMMARY OF THE INVENTION It is therefore a first object of the present invention to provide a DTR color photographic element having improved quality color images.

A second object of the present invention is to provide DTR with improved storage stability.
The objective is to provide photographic elements for color.

A third object of the present invention is to provide a DTR color photographic element having a highly transparent neutralization system. As a result of various studies, the present inventors have developed a neutralization system for lowering the pH of an alkali-treated composition [this neutralization system includes a neutralization layer and a timing layer, and this timing layer is a neutralization system for reducing the pH of an alkali-treated composition. The neutralizing layer is superimposed (directly or indirectly) on or below the neutralizing layer in a positional relationship such that the composition reaches the neutralizing layer via the timing layer.

] In the photographic element for color diffusion transfer method, the above-mentioned objects of the present invention can be achieved by coexisting acetylcellulose and a copolymer represented by the following general formula 1 in at least one layer of the timing layer. I found out what can be accomplished effectively. The photographic element further comprises a support; at least one
a light-sensitive element comprising a silver halide emulsion layer and a color image-donating substance associated with the silver halide emulsion layer; an image-receiving element in which diffusible dyes formed from the dye-image donor are fixed into an image; Other hydrophilic colloid layers may optionally be included; an alkaline processing composition that renders the exposed photosensitive element developable. Although the mixing of a polymer containing maleic acid as a comonomer component with acetylcellulose is described in the above-mentioned U.S. Pat. As described in the claims, it is clear that the invention is characterized by containing maleic anhydride as a comonomer component.

The present invention is characterized in that it does not contain maleic anhydride, but contains a certain amount or more of maleic acid or fumaric acid as a comonomer component, and is substantially free of maleic anhydride. different. General formula 1 [wherein A: - a polymerized co-monomer component represented by the general formula,
Me, I,? l\rl''N,2↓. Qualitatively does not contain one CH CH component), [wherein, R1: hydrogen atom, halogen atom, or methyl group, R2
:Hydrogen atom, halogen atom, preferably C, ~12 alkyl group, preferably C6-12 aryl group, ℃CH2
+AO-R3 group, °CCH2)-. a-0C-R4 group or -C-0-R5 group, R3: preferably a C1-12 alkyl group, or an aralkyl group (preferably a benzyl group),
R4, R5: may be the same or different, preferably C1-
8 alkyl group, preferably a C6-12 aryl group,
or preferably represents a C7-10 aralkyl group, a:O or 1.

] In the general formula 1, the alkyl group includes an unsubstituted alkyl group and a substituted alkyl group, and the aryl group and the aryl residue (MOiety) in the aralkyl group include an unsubstituted aryl group and a substituted aryl group.

Examples of substituents for the alkyl group of R3 include halogen atoms (chlorine, bromine, fluorine atoms) and preferably C1-6 alkoxy groups. Substituents for the aryl group of R2 include an acyl group (acetyl group, etc.), a hydroxy group, a halogen atom (chlorine, bromine, fluorine), preferably C1
-4 alkyl groups, preferably C1-4 alkoxy groups, and the like.

Examples of substituents for the alkyl group of R4 include halogen atoms (chlorine, bromine, and fluorine atoms).

Substituents for the aryl group of R4 and the aryl residue of the aralkyl group include halogen atoms (chlorine, bromine, fluorine atoms),
Preferably a C1-4 alkyl group, preferably C1-4
Examples include alkoxy groups. Examples of the substituent for the alkyl group of R5 include a halogen atom (chlorine, bromine, fluorine), an acyl group (such as an acetyl group), and a tetrahydrofuryl group.

As a substituent for the aryl group of R5 or the aryl residue of the aralkyl group, an acyl group (acetyl group), a halogen atom (chlorine, bromine, fluorine), preferably a C1-4 alkyl group,
Preferred examples include C1-4 alkoxy groups. The halogen atoms for R1 and R2 include chlorine, bromine, and fluorine atoms. The polymer represented by general formula 1 is
Copolymerization reaction between maleic acid or fumaric acid and a monomer that provides component A and component B, or maleic anhydride and component A and component B.
It is synthesized by hydrolyzing a polymer obtained by a copolymerization reaction with a monomer that provides a component. To explain in more detail, the monomers that provide component A are:
Examples include olefins, styrenes, pinylethers, vinyl esters, allyl compounds, acrylic esters, and methacrylic esters.

More specific monomers include olefins such as ethylene, propylene, butylene, isobutylene, hexene, dodecene, vinyl chloride, and vinylidene chloride, and styrenes such as styrene, vinyltoluene, α-methylstyrene, and dimethyl. Styrene, chlorostyrene, bromustyrene, trifluorostyrene, etc. Vinyl ethers include methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, chloroethyl vinyl ether, benzyl vinyl ether, etc. Vinyl esters include vinyl acetate, vinyl propionate, Vinyl butyrate, vinyl benzoate, vinyl chloroacetate, vinyl caproate, etc. Allyl compounds include allyl acetate, allyl caproate, allyl butyl ether, allyl octyl ether, etc. Acrylic esters include methyl acrylate, Examples of methacrylic acid esters include methyl methacrylate, ethyl methacrylate,
Examples include propyl methacrylate, butyl methacrylate, lauryl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, chloroethyl methacrylate, and ethoxyethyl methacrylate.

Among these, olefins, styrenes, vinyl ethers, acrylic esters, and methacrylic esters are preferred, and styrenes and vinyl ethers are particularly preferred. Specific examples of monomers that provide one CH--CH component include maleic acid and fumaric acid.

Examples of monomers providing component B include acrylamides, methacrylamides, vinyl heterocyclic compounds, unsaturated nitriles, itaconic acids, maleic acid diesters, fumaric acid diesters, crotonic acids, and vinyl ketones.

More specific monomers include acrylamide, methylacrylamide, butylacrylamide, diethylacrylamide,
N-(1,1-dimethyl-3-oxobutyl)acrylamide, acryloylmorpholine, etc.: Examples of methacrylamides include methacrylamide, methylmethacrylamide, tertbutylmethacrylamide, phenylmethacrylamide, dimethylmethacrylamide, methacryloylmorpholine, Methacryloylpiperidine, etc.; vinyl heterocyclic compounds include, for example, N-vinylpyrrolidone, N-vinyloxazolidone, N-vinyltriazole, N-vinylsuccinimide, etc.; unsaturated nitriles include, for example, acrylonitrile, methacrylonitrile, maleonitrile Itaconic acids include itaconic anhydride, itaconic acid, monoethyl itaconate, dimethyl itaconate, etc. Maleic diesters include dimethyl maleate, diethyl maleate, etc.
Dibutyl maleate, etc.; fumaric acid diesters include dimethyl fumarate, diethyl fumarate, dibutyl fumarate, etc.; crotonic acids include crotonic acid, methyl crotonate, ethyl crotonate, etc.
Examples of vinyl ketones include methyl vinyl ketone,
Examples include methyl isopropenyl ketone and phenyl vinyl ketone. Among these, acrylamides, methacrylamides, vinyl heterocyclic compounds, unsaturated nitrites, itaconic acids, maleic acid diesters, and fumaric acid diesters are preferred, and in particular acrylamides, vinyl heterocyclic compounds, unsaturated nitrites, and maleic acid. Acid diesters are preferred. Regarding the composition ratio of the copolymer, X is 20 to 70 mol%, preferably 30 to 70 mol%.

y is 30 to 50 mol%, especially 30 to 45 mol%
is preferred. z is O to 30 mol%, preferably 0 to 20 mol%, particularly preferably O to 15 mol%. The molecular weight of the copolymer is not particularly limited, but from the viewpoints of polymer solubility, miscibility with acetyl cellulose, handling, etc., it is preferably 1,000 to 1,000,000, and particularly preferably 5,000 to 500,000.

For the synthesis of the copolymer represented by the general formula 1 used in the present invention, British Patent No. 1211039, Japanese Patent Publication No. 47-2
No. 9195, Patent Application No. 7174, Patent Application No. 1977-2
No. 3466, patent application No. 4759743, patent application No. 1975-3
No. 1355, Japanese Patent Application Publication No. 49-135619, British Patent No. 961395, U.S. Patent No. 3227672, No. 3
No. 290417, No. 3262919, No. 3245
No. 932, No. 2681897, No. 3230275
JOhnC.PetrOpOulO, JOhnC.PetrOpOulO, et al.
setal:0fficia1Digest)33,7
19-736 (1961), J. AOyagi. l. S
hinOhara. “J.ApPl.POlym-SC
i.'' 16(2), 449-460 (1972), ``E.
ncycleOpediaOfpOlymerscient
ceandtechnOlOgy” 1, 67-95, C
．． D. ChOw. “J.Appl.POlym.ScN
2Ol6l9-1626 (1976), C. Cazec
tal. "J. MacrOmOl. Sci." A9 (1
) 29-43 (1975). R. B. Seymoure
tal. "POlynler" 1721-24 (197
6), “Polymer” 14 (156) 217-223 (19
It is convenient to perform this by referring to the method described in 65).

It goes without saying that those skilled in the art can easily change the polymerization initiator, concentration, polymerization temperature, reaction time, etc. in a wide range and easily depending on the type of polymer desired to be synthesized. is generally carried out at a temperature of 20 to 1801°C, preferably 40 to 120°C.

The polymerization reaction is usually carried out at a concentration of 0.05 to 5
It is carried out using % by weight of a radical polymerization initiator.
Examples of initiators include azobis compounds, peroxides, hydroperoxides, redox catalysts, and more specifically potassium persulfate, tert-butyl peroctoate, benzoyl peroxide, isopropyl percarbonate, 2,4-dichlorobenzoyl. Peroxide, methyl ethyl ketone peroxide, cumene hydroperoxide, dicumyl peroxide, azobisisobutyronitrile, etc. Typical specific examples of the copolymer represented by the general formula 1 used in the present invention will be listed below, but the copolymer is not limited thereto.

Copolymer Next, a specific synthesis example will be explained. Synthesis Example 1 (Synthesis of the above-mentioned copolymer 2)
Styrene 624y1 Maleic acid 4
64y1 acetone 4ml isopropyl alcohol 40
Add 0ml of benzoyl peroxide 107 and dissolve.

After replacing the air in the flask with nitrogen gas, raise the temperature and perform riblux. The mixture was stirred for 4 hours with riblaxation, and then a solution of benzoyl peroxide 2y dissolved in a mixed solution of 150 ml of acetone and 150 ml of isopropyl alcohol was added to the above solution, and the mixture was further stirred at 60° C. for 2 hours.

500 ml of methanol is added to dissolve the product adhering to the flask, and the temperature is lowered. The reaction mixture was poured into a 10-fold excess of water with vigorous stirring, and the precipitate was thoroughly washed with water, taken out, and dried in a vacuum dryer.

Yield 1040y30℃, ηSP constant in acetone
/C was 0.18. The composition ratio of maleic acid determined by potentiometric titration was 38 mol%. Synthesis Example 2 (Synthesis of Copolymer 9)
468f of styrene, 5227% of maleic acid, 42.6r of acrylamide, 390ml of isopropyl alcohol, 390ml of acetone, and 10.57ml of benzoyl peroxide were placed in a three-piece flask and dissolved.

After replacing the air in the flask with nitrogen gas, the temperature was raised to 75°C and stirred. The polymerization reaction begins, and the temperature temporarily rises exothermically to about 85°C. After that, it was stirred at 75°C for 5 hours, and further stirred for 4 hours.
．． 51 of benzoyl peroxide to 1 of isopropyl alcohol
Add the solution dissolved in a mixed solution of 00ml and 100ml of acetone. After stirring for an additional 3 hours at 70°C, 750 m
Add methanol from step 1 and cool down. The reaction mixture was poured into about 151 g of distilled water while vigorously stirring with an agitator, and the precipitated polymer was sufficiently washed with water, taken out and vacuum dried. The yield was 5 mol% of acrylamide as determined by 950y1 elemental analysis, and 47 mol% of maleic acid as determined by potentiometric titration.

ηSP/C measured in acetone at 30°C was 0.21.

The mixing ratio of the copolymer of the present invention and acetylcellulose used in the neutralization timing layer of the present invention (depending on the degree of acetylation of the acetylcellulose used in combination) is 1 to 20% relative to the acetylcellulose. Weight % is appropriate,
Preferably it is 2 to 15% by weight. The degree of acetylation of acetylcellulose is suitably 45 to 60%, preferably 50 to 55% (a degree of acetylation of 50 to 55% is 10% to 50%).
50 to 5 by hydrolyzing acetylcellulose of 07
(meaning that 5f acetic acid is produced). The timing layer of the present invention can be provided by dissolving a mixture of cellulose acetate and the copolymer of the present invention in an organic solvent such as acetone or cyclohexanone (singlely or as a mixture) and applying the solution directly or indirectly onto the neutralization layer. can.

Here, "indirectly" means coating on the neutralizing layer via another layer such as a timing layer or an adhesion improving layer. For the neutralization layer, it is preferable to use a film-forming acidic polymer, and any such acidic polymer can be used.

Examples of the acidic polymer include monobutyl ester of a copolymer of maleic anhydride and ethylene, monobutyl ester of a copolymer of maleic anhydride and methyl vinyl ether, monoethyl ester of a copolymer of maleic anhydride and ethylene, and the above. monopropyl esters of the mentioned copolymers,
Monopentyl ester of the same copolymer, monohexyl ester of the same copolymer, monoethyl ester of the copolymer of maleic anhydride and methyl vinyl ether, monopropyl ester of the same copolymer, monobenzyl ester of the same copolymer , monohexyl esters of the same copolymers, polyacrylic acid, polymethacrylic acid, copolymers of acrylic acid and methacrylic acid in various ratios, acrylic acid or methacrylic acid and other vinyl monomers (e.g. acrylic esters,
methacrylic acid esters, vinyl ethers, acrylamides, methacrylamides, etc.) (preferably, the acrylic acid or methacrylic acid content is 50 to
90 mol%) copolymers, etc. can be used. Regarding the neutralizing layer, see US Pat. No. 3,362,819 and US Pat. No. 3,376
No. 5885, No. 3819371, French Patent No. 22
It is also described in No. 90699.

Among these, polyacrylic acid and acrylic acid-butyl acrylate copolymer are recommended. Further, the neutralization timing layer of the present invention can be used to prevent the permeation of alkaline processing liquids as described in, for example, U.S. Pat. No. 4,056,394, U.S. Pat. It is also effective to use a polymer layer with a high temperature dependence in order to widen the allowable processing temperature range.

The neutralized timing layer may also contain a development inhibitor precursor as described in U.S. Pat. No. 4,009,029.

The silver halide emulsion used in the present invention is a hydrophilic colloidal dispersion of silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiodobromide, or a mixture thereof, and the halogen composition is Silver iodobromide is selected depending on the use and processing conditions of the photosensitive material, but has an iodide content of 1 mol% to 10 mol% (chloride content is 30 mol% or less), and the remainder is bromide. or silver chloroiodobromide emulsions are particularly preferred.

Emulsions that easily form latent images on the grain surfaces can also be used in the present invention, but US Pat.
82, 3456953, 3761276, 320
It is preferable to use internal latent image type direct reversal emulsions such as those described in No. 6313, No. 3317322, No. 3761266, No. 3850637, No. 3923513, No. 3736140, No. 3761267, and No. 3854949.

Color image-providing materials for diffusion transfer methods used in combination with the photographic emulsion of the present invention include, for example, US Pat.
No. 227551, No. 3227554, No. 3255001, No. 3443939, No. 3443940, No. 3482972, No. 3554545, No. 3551406, No. 3563739, No. 3658524, No. 3698897, No. 3725062, No. 3728113 , No. 3751406, No. 3854945, No. 3880658, No. 3929760 , No. 3931144, No. 3932381, British Patent No. 840
No. 731, No. 904364, No. 1038331, West German Patent Publication (0LS) No. 1930215, No. 2214381, No. 2228361, No. 2242762, No. 231713
No. 4, No. 2402900, No. 2406626, No. 2406653, No. 2406664, JP-A-49-1
No. 14424, No. 49-126332, No. 48-3382
No. 6, No. 49-126331, No. 50-115528,
51-113624, 51-104343, 51-
No. 114930, No. 52-8827, No. 52-63324
No. 52106727, No. 53-23628, Japanese Patent Application No. 52-58318, No. 52-64533, No. 52-
No. 74601, No. 52-131278 Research
hDisclOsure magazine volume 166 F6. l6629(
A variety of compounds can be used, including the dye developing agents described in (published in February 1978), among others, compounds that are initially non-diffusible but cleave after a redox reaction with the oxidation product of the developing agent. A type of color image-providing substance that releases a diffusible dye (hereinafter referred to as a diffusible dye-releasing redox compound)
R compounds) are preferred.

Specific examples of DRR compounds include those described in the above patent specifications, as well as magenta dye image forming substances such as 1
-Hydroxy-2-tetramethylenesulfamoyl-4
-[3'-Methyl-4'-(g-hydroxy-4''-methyl-57-hexadecyloxyphenylsulfamoyl)-phenylazo]-naphthalene, yellow as dye image-forming material, 1-phenyl-3- Cyano-4-+3'
+7-hydroxy-14″-methylude (-2″5・41
Examples include ``-di-t-pentylphenoxyacetamino)-phenylsulfamoyl]phenylazo}-5-pyrazolone.

When using a DRR compound in the present invention, any silver halide developer can be used as long as it can cross-oxidize the DRR compound.

Such a developer may be included in the alkaline processing composition (processing element) or in an appropriate layer of the photosensitive element. Examples of developing agents that can be used in the present invention are as follows. Hydroquinone, aminophenol (e.g. N-methylaminophenol), 1-phenyl-3-pyrazolidone, 1-phenyl-4,4-dimethyl-3-pyrazolidone, 1-phenyl-4-methyl-
4-oxymethyl-3-pyrazolidone, N·N-diethyl-p-phenylenediamine, 3-methyl-N-N-diethyl-p-phenylenediamine, 3-methoxy-N-
Ethoxy-p-phenylenediamine and the like. Among those listed here, black and white developers are particularly preferred, as they generally have properties that reduce stain formation in the image receiving layer (mordant layer).

The direct reversal photographic emulsion that can be used in the present invention may be developed after image exposure in the presence of a fogging agent or
After image exposure, uniform exposure (
A positive image can be directly obtained by applying a high-intensity, short-time exposure (ie, exposure shorter than 10-2 seconds, or a low-intensity, long-term exposure) to cause fogging.

It is preferable to use a fogging agent because the degree of fogging can be easily adjusted. The fogging agent may be contained in the light-sensitive material or may be added to the developer, but it is preferable to contain it in the light-sensitive material. Fogging agents for this type of emulsion include U.S. Pat.
Hydrazines described in No. 85, hydrazides and hydrazones described in No. 3227552, British Patent No. 128
No. 3835, Japanese Patent Publication No. 49-38164, U.S. Patent No. 37
No. 34738, No. 3719494, No. 3615615
The quaternary salt compounds described in No. 1 and the West German patent application (0L
The acylhydrazinophenylthiourea compounds described in S) No. 2635316 are representative.

The amount of force brushing agent used herein can vary widely depending on the desired result. The concentration of this force brushing agent, when added to a photosensitive material, generally varies depending on the fogging agent used, but is 0.1T119 to 15
00η/1 mol A7, preferably 0.5η to 700η/
It is used within the range of 1 mol A7. When a power brushing agent is added to the developer, it is generally about 0.0% per developer 11.
5 to 5y (preferably 0.1 to 17).

When a power brushing agent is included in any layer of a photosensitive material, it is also effective for this purpose to make the power brushing agent diffusion resistant. An effective means for imparting diffusion resistance is to bond a ballast group, which is commonly used in couplers, to a fogging agent. Furthermore, the DIR reversal emulsion system as described in U.S. Pat.
A transfer positive image can also be obtained by a reversal emulsion system using dissolution physical development as described in No. 364.

U.S. Patent Nos. 3,227,550 and 3,227,552;
A series of processes for obtaining color diffusion transfer images are described, such as in British Patent No. 1330524.

In the present invention, diffusible dye releasing couplers (DDR couplers)
As a color developing agent when using
No. 27552, No. 2559643 and No. 38132
Paraphenylenediamine derivatives described in No. 44 are representative. Furthermore, JP-A-48-26134
p-aminophenol derivatives, such as those described in , can also be used advantageously. Such color developing agents are preferably present in an alkaline developing processing composition contained in a breakable container. The color developing agent may also be contained in a separate layer in the negative portion of the film, unit, or it may be present in the same layer as the silver halide emulsion layer. The image receiving element is a poly-4-vinylpyridine latex (particularly in polyvinyl alcohol) as described in U.S. Pat. No. 3,148,061.
, polyvinylpyrrolidone described in US Pat. No. 3,003,872, US Pat. No. 3,239,337, US Pat. No. 3,958,995, US Pat.
0LS) 2264073 etc.,
It is essential to have a mordant layer consisting of a mordant such as a polymer containing a quaternary ammonium salt or a phosphionium salt.

As a mordant, U.S. Patent Nos. 2,882,156 and 362
Basic polymers described in No. 5694 and No. 3709690 are also effective. Other U.S. Patents No. 2484430, U.S. Patent No. 3271147, U.S. Patent No. 3184309, U.S. Patent No. 327
Mordants described in No. 1147 and the like are also effective. The DTR color photographic elements of this invention have supports that do not undergo significant dimensional changes during processing.

Examples of such supports include cellulose acetate film, polystyrene film, polyethylene terephthalate film, polycarbonate film, etc. which are used in common photographic materials. Besides that,
Useful supports include, for example, paper and paper laminated on the surface with a water-impermeable polymer such as polyethylene. The processing composition used in the present invention is a liquid composition containing the processing components necessary for developing a silver halide emulsion and forming a diffusion transfer dye image, and the solvent is mainly water and methanol is also used. may also contain hydrophilic solvents such as methyl cellosolp. The processing composition maintains the pH necessary for development of the emulsion layer and removes acids generated during the development and dye image formation processes (e.g., hydrohalic acids such as hydrobromic acid, carboxylic acids such as acetic acid). Contains a sufficient amount of alkali to neutralize acids (acids, etc.). Examples of alkalis include alkali metal or alkaline earth metal salts such as lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide dispersion, tetramethylammonium hydroxide, sodium carbonate, trisodium phosphate, diethylamine, or amines. It is desirable to contain a caustic alkali at a concentration such that it has a pH of about 12 or higher at room temperature, particularly PH14 or higher. More preferably, the treatment composition comprises high molecular weight polyvinyl alcohol,
Contains hydrophilic polymers such as hydroxyethyl cellulose and sodium carboxymethyl cellulose.
These polymers can be added to the treatment composition at room temperature by at least 1 p.c.
It preferably provides a viscosity of about 500 to 600 to 1,000 poise, which not only facilitates the uniform spread of the composition during processing, but also prevents the aqueous solvent from migrating to the photosensitive element and image-receiving element during the processing process. When the processing composition is concentrated, it forms a non-flowing film that helps the film unit to integrate after processing. This polymer film can also be used to inhibit further migration of colored components to the image-receiving layer after the formation of the diffusion-transferred dye image is substantially completed, thereby preventing changes in the image. The processing composition may also contain light-absorbing substances such as TiO2, carbon black, and PH indicator dyes to prevent fogging of the silver halide emulsion by external light during processing, as described in US Pat. No. 3,579,333. It may be advantageous in some cases to contain desensitizers such as those mentioned.

Furthermore, a development inhibitor such as benzotriazole can be added to the processing liquid composition. The above treatment compositions are disclosed in U.S. Pat. No. 2,543,181, U.S. Pat.
It is preferable to use it in a rupturable container as described in No. 91, No. 3056492, No. 3152515, etc.

When the photographic element of the present invention is a film unit (i.e., a film unit adapted to be processed by passing the film unit between a pair of juxtaposed pressure members), it preferably
Contains the following elements: (1) to (3).

After exposure, the photosensitive element in the film unit is transferred to its image receiving element (which incorporates the neutralization system of the present invention).
and can be treated by spreading an alkaline treatment composition between the two elements.

In this case, the image-receiving element may be peeled off after transfer, or the image may be viewed without being peeled off, as described in US Pat. No. 3,415,645.

In another embodiment, the image-receiving layer in the film unit can be arranged integrally with the photosensitive element together with the support. For example, Pelkey Patent No. 757960
A transparent support is provided with an image-receiving layer, a substantially opaque light-reflecting layer (e.g. a TiO2 layer and a carbon black layer), and one or more light-sensitive silver halide emulsion layers as described above. It is effective to apply a photosensitive element consisting of: After exposure of the photosensitive element, it is placed face-to-face with an opaque cover sheet (incorporating the neutralization system of the present invention) and a processing composition is spread between the two. Another embodiment of the overlapping and integrated type to which the present invention can be applied is disclosed in Pelkey Patent No. 75795.
It is disclosed in No. 9.

According to this embodiment, an image-receiving layer, a substantially opaque light-reflecting layer (such as those described above), on a transparent support,
Then, a photosensitive element consisting of one or more photosensitive layers as described above is applied, and a transparent cover sheet (incorporating the neutralization system of the present invention) is placed on the surface. A rupturable container containing an alkaline processing composition containing an opacifying agent (eg, carbon black) is placed adjacent the top layer (protective layer) of the photosensitive element 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 between the photosensitive element and the cover sheet. It spreads over a whole area in between. As a result, the film unit is shielded from light and development proceeds. Other useful laminate forms in which DRR compounds or DDR couplers can be used in the present invention are U.S. Pat.
No. 7487 and No. 3635707, German Patent Application (0LS) No. 2426980.

Comparative Experimental Example 1 After dissolving 1.357 acetyl cellulose with an acetylation degree of 52.3% and 0.157 of various polymers shown below according to the present invention in 138.8y of acetone and 46.27y of cyclohexanone, each solution was dissolved in Hitachi Transmittance at 600 nm was measured using a Model 323 spectrophotometer.

As shown in Table 1, for comparison, U.S. Patent No. 402
It can be seen that the polymer of the present invention has higher transparency than the poly(styrene-co-mono-maleic anhydride) described in No. 9849 and has excellent compatibility with acetylcellulose. Example 1 Cover Sheet A cover sheet according to the present invention was prepared by applying polyethylene terephthalate to a transparent support soil as follows.

(1) A neutralizing layer in which 22y of acrylic acid-butyl acrylate (mole ratio 8:2) copolymer having an average molecular weight of about 50,000 was applied per square meter.

(2) Neutralized timing layer comprising acetylcellulose with a degree of acetylation of 52.3% and a copolymer shown in Table 2 in a weight ratio of 9:1 at 57 coatings per square meter.

Compared to a comparative cover sheet using poly(styrene-co-mono-maleic anhydride), the cover sheet of the present invention provided a coating film with better transparency.

PH indicator-coated film A PH indicator-coated film was prepared by coating a polyethylene terephthalate transparent support as follows.

(1) Indicator layer containing thymolphthalein (0.2y/M2) and gelatin (77/Trl).

(2) Titanium oxide (207/A) and gelatin (27
/m”).

(3) Same indicator layer as (1).

Processing liquid A processing liquid consisting of

The cover sheets prepared as described above and the cover sheets that had been forced to age for 3 days at 50°C and 80% relative humidity were each placed face to face with the PH indicator coated film, while the treatment solution was applied to a thickness of 80 μm. It was expanded to

Next, the concentration is measured from the side of the PH indicator-coated film, and the time required for the reflection density of the high PH color (blue) of thymolphthalein to decrease by half due to neutralization (this time is called the "neutralization timing time"). ) was measured at 25°C. The test results are shown in Table 2. As shown in Table 2, the copolymer of the present invention exhibits much less change in neutralization timing due to forced aging, making it difficult to provide a cover sheet with excellent storage stability. Example 2 A photosensitive sheet was coated on a polyethylene terephthalate transparent support as follows.

(1) The following polymer (3.0t/m”) and a mordant layer containing gelatin (3.07/M°).

(2) Titanium oxide 207/M2 and gelatin 2.07
A white reflective layer containing /m゛. (3) Carbon black 2.
707/Trl and gelatin 2.70y/M2.

(4) Diethyl laurylamide (0.107/M2)
and the following cyan image-providing substance (0.50y/wl) dissolved in tricresyl phosphate (0.06f/l)
, and a layer containing gelatin (1.14f7/Rrl) (
5) Red-sensitive internal latent image type direct reversal silver iodobromide emulsion (halogen composition in silver halide: 2 mol% of iodine, 2% of silver)
．． 5f7/I), gelatin 2.2y/I, a fogging agent represented by the following formula (0.20~/Trl), and sodium pentadecylhydroquinone sulfonate (0.137/Trl).
Layer fogging agent containing a) 3) Gelatin (2.61/a)
Layer 1) containing 2,5-dioctyl .
The following magenta color image-donor substance (0,4 ml) dissolved in
57/d) and 2,5-di-t-butylhydroquinone (0.0074y/7rI), and gelatin (0.
layer (8) containing a green-sensitive internal latent image type direct reversal silver iodobromide emulsion (halogen composition of silver iodobromide: 2 mol% iodine, 2.1 f/a silver content), Gelatin 1.91/I, the same fogging agent added to layer (5) (0.10η/
layer (9) gelatin (2.1y/d), tricresyl phosphate (1.9
A layer containing 2,5-dimioctylhydroquinone (0.85 r/l) dissolved in diethyl laurylamide (0.161 r/l) as described below (0.85 r/l). 78f7/a) and 2.5-jit
- Layer 00 containing butylhydroquinone (0.0127y/y) and gelatin (0.78y/y) blue-sensitive internal latent image type direct reversal silver iodobromide emulsion (halogen composition of silver iodobromide: iodine mole %, in amount of silver 1.7?/A), gelatin 1.67/M2, the same fogging agent added to layer (5) (0.09IT!If!/M2) and pentadecylhydroquinone sulfonic acid. Sodium (0.094V/m
Layer (self) containing 1) Layer processing solution containing gelatin (0.947/m'') A processing solution having the above composition was filled into a container that could be broken at a pressure of 0.87.

Cover sheet A cover sheet was prepared by coating polyethylene terephthalate on a transparent support in the following order.

(1) A neutralizing layer coated with 22'I7 of monobutyl acrylate (mole ratio 8:2) copolymer having an average molecular weight of 50,000 per square meter. (2) Acetylation degree 52.1%
acetyl cellulose and the above copolymer 2 in a ratio of 95:5.
Neutralized timing layer coated with 67/Rrl and 0.092y/I of 5-(2-cyanoethylthio)-1-phenyltetrazole in a weight ratio of . (3) A neutralized timing layer made of a polymer latex obtained by emulsion polymerization of styrene-butyl acrylate-acrylic acid in a weight ratio of 52:42:6 and coated with a solid content of 3f7 per square meter.

Processing process The above cover sheet and the above photosensitive sheet were overlapped and exposed through a color test chart from the side of the cover sheet, and then the above processing solution was spread between both sheets to a thickness of 85 μm (spreading was done by applying pressure). (I did it with the help of a roller).

Claims (1)

[Scope of Claims] 1. A neutralization system for lowering the pH of an alkaline treatment composition. [This neutralization system includes a neutralization layer and a timing layer, wherein the timing layer is such that the alkaline treatment composition has a timing layer. The neutralizing layer is superimposed (directly or indirectly) on or below the neutralizing layer in such a positional relationship that it reaches the neutralizing layer via the neutralizing layer. ], wherein at least one layer of the timing layer contains a mixture of acetylcellulose and a polymer represented by the following general formula I. General formula I ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, A: co-monomer component represented by general formula II,
B: Other ethylenic co-monomer components (however, ▲mathematical formulas, chemical formulas, tables, etc.▼-components are not included), x: 20 to 70 mol%, y: 30 to 50 mol%, z: 0 to 30 mol%. ] General formula II ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [In the formula, R_1: hydrogen atom, halogen atom or methyl group, R_2
: Hydrogen atom, halogen atom, alkyl group, aryl group,
-(CH_2)_a-O-R_3 group, ▲mathematical formula, chemical formula,
There are tables, etc. ▼ groups or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ R_5 group, R_3: alkyl group or aralkyl group, R_4, R_
5: alkyl group, aryl group or aralkyl group (which may be the same or different); a: 0 or 1; ]