JP2913529B2 - Internal latent image type direct positive silver halide emulsion and color diffusion transfer photographic film unit using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal latent image type direct positive silver halide emulsion and a color diffusion transfer photographic film unit using the emulsion.

[0002]

2. Description of the Related Art A photographic method using silver halide has excellent sensitivity and gradation characteristics as compared with other photographic methods, for example, an electrophotographic method or a diazo photographic method, and has been widely used. . Among them, a method of directly forming a positive image is known. This is described, for example, in US Pat.
No. 76 and Japanese Patent Publication No. 60-55821, an internal latent image type direct positive silver halide photographic emulsion is used to form a silver halide grain having an internal latent image formed on the surface developer (silver halide grain). When developing with a developing solution that leaves the latent image forming site inside substantially undeveloped), a positive image is obtained by giving uniform exposure or using a nucleating agent.

It has been shown in US Pat. No. 2,448,06 that silver halide emulsions can be sensitized by adding a transition metal compound at several stages in the manufacture of the silver halide emulsion.
No. 0. It is known that there is a remarkable difference in the photographic effect of a transition metal compound in a silver halide emulsion between the case where a transition metal compound is added during silver halide grain formation and the case where it is added after silver halide grain precipitation. I have. The former case is particularly called a metal dopant. These are described in Research Disclosure, Vol. 176, December 1978.
Described in Monthly Issue, Item 17643.

In an internal latent image type direct positive silver halide photographic emulsion, it is known that doping with a metal ion enhances a low density portion on an inversion characteristic curve. This is described, for example, in U.S. Pat.
367,778, 3,447,927, 3,5
Nos. 31, 291 and 3,761, 267 and 3, 76
Nos. 1,276, 3,850,637, 3,92
Nos. 3,513, 4,035,185, 4,44
4,874, 4,444,865, 4,43
Nos. 3,047 and 4,395,478 and British Patent Nos. 1,151,782 and 1,529,011. However, it has been known that the hardening of the low concentration portion on the inversion characteristic curve by doping the metal ion is not at a sufficiently satisfactory level, and that the maximum concentration is lowered. Further, these patents do not specify the ligand of the metal ion or describe the effect thereof.

On the other hand, European Patent No. 0,336,425,
JP-A-0,336,426, JP-A-2-20853 and JP-A-2-20854 disclose sensitivity in the presence of a six-coordinate rhenium, ruthenium, osmium and iridium metal complex having at least four cyanide ligands. Further, a silver halide emulsion having excellent gradation stability over time and improved low illuminance failure is described. Here, it has been recognized that the hexacoordinate transition metal complex is accommodated in the space of a single halide ion vacancy inside the crystal structure,
This differs from the conventional general view that the transition metal is incorporated into the silver halide grains as a single ion or atom. However, in this patent, the types of transition metals are limited to rhenium, ruthenium, osmium and iridium, and chromium, manganese, cobalt and rhodium are not described. No mention is made of an internal latent image type direct positive silver halide emulsion.

Japanese Patent Application Laid-Open No. 2-259,749 discloses that an internal latent image type direct positive silver halide emulsion containing a hexacyanoiron complex among iron complexes has a high maximum density, a low minimum density, and a high reproducibility at high illuminance exposure. It is described that a direct positive silver halide photographic light-sensitive material with less occurrence of a reversal negative image can be obtained, but the central metal is limited to iron, and chromium, manganese, cobalt, iridium, ruthenium, rhodium, rhenium and Osmium is not described.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an internal latent image type direct positive silver halide emulsion having a high sensitivity and a low contrast in a low density portion on an inversion characteristic curve, and a color diffusion transfer photographic film using the same. Is to provide a unit.

[0008]

The object of the present invention is as follows.
(1), (2) and (3) internal latent image type direct positive halogen
Silver halide emulsion and color diffusion transfer photographic film using the same
Achieved by the unit. (1) At least a metal complex represented by the following general formula (I)
Of particles in a dispersion medium containing one(However, thio is added to the side chain.
Ethylenically unsaturated having at least one ether structure
Disassemble a polymer having a repeating unit derived from a monomer
Excluding the case where particles are formed by using as a lubricant)Features
Internal latent image type direct positive silver halide emulsion. General formula (I) [M (CN)₆]^n-  In the formula, M: Cr, Mn, Co, Ir, Ru, Rh, Re, Osn: 3 or 4 (2) An internal latent image type direct positive halogeno represented by the above (1)
Silver halide emulsion having an average grain diameter of 0.3 μm or more,
Tabular halogenation having a diameter / average grain thickness ratio of 2 or more
It is characterized in that silver grains contain at least 50% of all silver halide grains.
Internal latent image type direct positive silver halide emulsion. (3) an image receiving layer, a white reflective layer, a light shielding layer,
Reduced amount in combination with at least one dye image-forming substance
A photosensitive sheet having at least one silver halide emulsion layer,
At least a neutralization layer and a neutralization timing layer on a transparent support
A transparent cover sheet, and the photosensitive sheet and the front
It is designed to be spread between the transparent cover sheets
Color diffusion transfer copying composed of light-shielding alkali-treated composition
In the true film unit, the silver halide emulsion layer
At least one layer of (1) and / or (2)
Features a latent image type direct positive silver halide emulsion
Color diffusion transfer photographic film unit.

Hereinafter, the present invention will be described in more detail. As a counter ion of the metal hexacyanide complex used in the present invention, alkali metal ions such as potassium and sodium are preferably used.

The amount of the metal hexacyanide complex used in the present invention is preferably 10 ^-10 mol or more and 10 ^-4 mol or less per mol of silver halide, and is preferably 1.0 to 10 ^-4 mol per mol of silver halide. × 10 ⁻⁸ mol or more and 1.0 × 1
Still more preferably 0 ^-6 mol or less.

The metal hexacyanide complex used in the present invention may be added and contained during the preparation of silver halide grains, that is, before or after nucleation, growth, physical ripening, and chemical sensitization. The pAg at the time of adding these metal hexacyanide complexes during the preparation of silver halide grains is preferably 6 or more, and more preferably 7 or more.

The metal hexacyanide complex used in the present invention is preferably dissolved in water or a suitable solvent and added. In order to stabilize the solution, an aqueous solution of hydrogen halide (eg, HC
1, HBr, etc.) or an alkali halide (eg, KCl, NaCl, KBr, NaBr, etc.) can be used. If necessary, an acid or alkali may be added.

The metal hexacyanide complex used in the present invention may be added directly to the reaction solution when forming silver halide grains, or may be used in an aqueous halide solution for forming silver halide grains, in an aqueous silver salt solution, or in any other solution. Is preferably added to the above solution to form particles. It is also preferable to combine various addition methods.

When the metal hexacyanide complex used in the present invention is added, the concentration of hydrogen ions in the reaction solution is preferably pH = 1 or higher, more preferably pH = 3 or higher.

The metal hexacyanide complex used in the present invention can be used in combination with other metal ions. Mg, Ca, Sr, Ba, Al, Sc, Y, La, C
r, Mn, Fe, Ni, Cu, Zn, Ga, Ru, R
h, Pd, Re, Os, Pt, Au, Cd, Hg, T
1, In, Sn, Pb, Bi and the like can be used. These metals are ammonium, acetate, nitrate,
It can be added in the form of a salt that can be dissolved at the time of particle formation, such as a sulfate, a phosphate, a hydroxide, or a six-coordinate complex, or a four-coordinate complex.

The present invention is applied to an internal latent image type direct positive silver halide emulsion. An internal latent image type direct positive silver halide emulsion (hereinafter sometimes abbreviated as an internal latent image type silver halide emulsion) is a type which forms a latent image mainly inside silver halide grains upon image exposure. With silver halide emulsion,
Specifically, a fixed amount of a silver halide emulsion is coated on a transparent support and exposed to the solution for a fixed time of 0.01 to 1 second, and the following developer A ("internal type" developer) Inside,
The maximum density obtained when developing at 20 ° C. for 5 minutes is as follows.
("Surface" developer) is defined as having a density at least 5 times greater than the maximum density obtained when developed for 5 minutes at 20 ° C. Here, the maximum density is measured by an ordinary photographic density measurement method. Developer A N-methyl-p-aminophenol sulfite 2 g Sodium sulfite (anhydrous) 90 g Hydroquinone 8 g Sodium carbonate (monohydrate) 52.5 g Potassium bromide 5 g Potassium iodide 0.5 g B N-methyl-p-aminophenol sulfite 2.5 g 1-ascorbic acid 10 g potassium metanitrate 35 g potassium bromide 1 g 1 liter by adding water As an internal latent image type silver halide emulsion, for example, US Pat. , 953, and 2,592,250, and the like, and a first phase and a second phase as described in U.S. Pat. No. 3,935,014. Layered silver halide emulsion with different halogen composition of the phase, doping with metal ions, or Such core / shell type silver halide emulsion coated with shell academic sensitized core particles. Among these, a core / shell type silver halide emulsion is particularly preferred as the internal latent image type silver halide emulsion used in the present invention.
For example, U.S. Pat.
317,322, 3,761,266, 3,7
61,276, 3,850,637, 3,92
Nos. 3,513, 4,035,185, 4,18
4,878, 4,395,478 and 4,50
4,570, JP-A-57-136641, 61-
No. 3137, JP-A-61-299155, JP-A-62
-208241 and the like. In order to directly obtain a positive image, a uniform second exposure is applied to the front surface of the exposed layer before or during development after image exposure of the above internal latent image type silver halide emulsion ("light fogging method"). For example, British Patent 1,151,363) or
Alternatively, development is performed in the presence of a nucleating agent ("chemical fogging", for example, Research Disclosure (Resear
ch Disclosure), Volume 151, No. 15162, 76-7
8), but in the present invention, a method of directly obtaining a positive image by the "chemical fogging method" is preferable. The nucleating agent used in the present invention will be described later. As described above, in order to directly obtain a positive image using an internal latent image type silver halide emulsion, a uniform second exposure is applied to the entire surface after image exposure, before development processing or during development processing, or It can be obtained by performing development processing in the presence of a nucleating agent. As a nucleating agent, US Pat. No. 2,563,785
Hydrazines described in U.S. Pat. No. 2,588,982, hydrazides described in U.S. Pat. No. 3,227,552, hydrazones, and British Patent 1,283,835.
No. JP-A-52-69613 and JP-A-55-138742.
No., No. 60-11837, No. 62-210451,
No. 62-291637, U.S. Pat. No. 3,615,515
Nos. 3,719,494 and 3,734,738
No. 4,094,683, 4,115,122
And heterocyclic quaternary salt compounds described in US Pat.
Sensitizing dyes having a nucleating substituent in a dye molecule described in US Pat. No. 4,030,925, US Pat. No. 4,031,127, US Pat. 4,255,511, 4,266,013, 4,276,364, British Patent 2,012,443 and the like, and thiourea-bonded acylhydrazine compounds described in US Pat. 080,270, 4,27
No. 8,748, British Patent No. 2,011,391B and the like, a siahydrazine-based compound having a thioamide ring or a heterocyclic group such as triazole or tetrazole bonded as an adsorptive group is used. The amount of the nucleating agent used here is desirably an amount that gives a sufficient maximum density when the internal latent image type emulsion is developed with a surface developer.
In practice, the appropriate content may vary over a wide range because it depends on the characteristics of the silver halide emulsion used, the chemical structure of the nucleating agent and the development conditions. A range of about 0.1 mg to 5 g per mole is practically useful, preferably about 0.5 mg / mol silver.
２2 g. When it is contained in the hydrophilic colloid layer adjacent to the emulsion layer, the same amount as described above may be contained with respect to the amount of silver contained in the inner latent emulsion having the same area.

In the present invention, various shapes of silver halide grains can be used. Examples include those having regular crystal forms such as cubes, octahedrons, tetradecahedrons, and rhombic dodecahedrons, those having irregular crystal forms such as spheres, plates, etc. Those having the following plane ((hk1) plane) or a mixture of these crystal-form particles can be given. For particles with higher planes, see the Journal of Imaging Science.
maging Science), 247 of Volume 30 (1986)
Pages 254 to 254 can be referred to. The silver halide grains used in the present invention may be normal crystals containing no twin planes. 163, such as a single twin with one twin plane, a parallel multiple twin with two or more parallel twin planes, a non-parallel with two or more non-parallel twin planes It can be selected from multiple twins or the like depending on the purpose. An example of mixing particles having different shapes is disclosed in U.S. Pat. No. 4,865,964, but this method can be selected as necessary. In the case of normal crystals (10
A cube consisting of a 0) plane, an octahedron consisting of a (111) plane,
JP-B-55-42737, JP-A-60-222842
Dodecahedral particles having the (110) plane disclosed in the above publication can be used. Furthermore, Journal of Imaging S
(hl1) plane particles represented by (211) as reported in Science, 30, 247, 1986;
(Hh1) plane particles represented by (331), (210)
The (hk0) plane particles represented by the plane and the (hk1) plane particles represented by the (321) plane also need to be devised in the preparation method, but can be selected and used depending on the purpose. Tetradecahedral particles in which the (110) plane and the (111) plane coexist in one particle,
Particles in which two or many surfaces coexist, such as particles in which (100) and (110) surfaces coexist, or particles in which (111) and (110) surfaces coexist, should be selected and used according to the purpose. Can be.

The silver halide composition of these grains may be any of silver bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide, silver chloroiodide and silver chloride. However, silver bromide and silver iodobromide are preferred. Further, other silver salts such as silver thiocyanate, silver cyanate, silver sulfide,
Silver selenide, silver carbonate, silver phosphate, and organic acid silver may be contained as separate grains or as a part of silver halide grains.

The silver halide grains may have different phases between the inside and the surface layer, or may consist of a uniform phase.
The silver halide composition in the grains may be uniform, the inside and the outside may be composed of different silver halide compositions, or may have a layered structure. (JP-A-57-15
No. 4232, No. 58-108533, No. 58-248
No. 469, No. 59-48755, No. 59-52237
No. 3,505,068, U.S. Pat.
048, 4,444,877, EP 10
0,984 and British Patent 1,027,146)
Further, particles having dislocation lines may be used.

In the case of silver halide grains in which two or more silver halides are present as a mixed crystal or with a structure, it is important to control the halogen composition distribution between the grains. The method for measuring the halogen composition distribution between grains is described in JP-A-60-254032. Uniform halogen distribution between grains is a desirable property. In particular, a highly uniform emulsion having a coefficient of variation of 20% or less is preferable.
Another preferred form is an emulsion having a correlation between the grain size and the halogen composition.

It is important to control the halogen composition near the surface of the grains. Increase the silver iodide content near the surface,
Alternatively, increasing the silver chloride content can be selected according to the purpose because the adsorption property of the dye and the developing speed are changed.
When changing the halogen composition in the vicinity of the surface, either a structure that covers the entire grain or a structure that adheres only a part of the grain can be selected. For example, (100) plane and (11)
1) The case where the halogen composition is changed only on one side of the tetradecahedral grain composed of planes, or the case where the halogen composition on one side of the main plane of the tabular grain is changed.

The grain size of the emulsion used in the present invention is determined by the equivalent circle diameter of the projected area using an electron microscope, the equivalent sphere diameter of the particle volume calculated from the projected area and the grain thickness, or the equivalent sphere diameter of the volume by the Coulter counter method. Can be evaluated. Ultrafine particles having an equivalent sphere diameter of 0.05 μm or less and coarse particles exceeding 10 μm can be selected and used. Particles having a size of 0.1 μm or more and 3 μm or less are preferred. The grain size distribution of the silver halide grains is arbitrary, but may be monodispersed. Here, monodispersion is
It is defined as a dispersion in which the total weight or 95% of the total number of silver halide grains contained therein falls within ± 60%, preferably within 40%, of the number average grain size.
Here, the number average grain size is the number average diameter of the projected area diameter of the silver halide grains. Monodisperse emulsions are described in U.S. Pat. Nos. 3,574,628 and 3,655,394 and British Patent 1,413,748. These monodisperse emulsions may be used as a mixture. You may.

It is possible to use two or more kinds of silver halides having different crystal habits, halogen compositions, grain sizes, grain size distributions, etc., and to use them in different emulsion layers and / or the same emulsion layer. It is possible to

In the present invention, more preferable effects can be obtained when tabular silver halide grains are used. Regarding tabular silver halide grains, Cleve, Photography Theory and Practice
(1930)), 131; Gatof, Photographic Science and Engineering (Gutof)
f, Photographic Science and Engineering), 14th
Vol. 248-257 (1970); U.S. Pat.
434,226, 4,414,310, 4,4
33,048, 4,439,520, 4,41
No. 4,306, 4,459,353, British Patent No. 2,112,157, JP-A-59-99433, JP-A-62-209445, and the like disclose the production method and use technology. In particular, US Pat. No. 4,395,478 discloses a tabular internal latent image type direct positive silver halide emulsion.
Nos. 4,504,570 and 4,996,137
No., JP-B-64-8327, JP-A-1-131547.
No. is described in detail. These tabular internal latent image type direct positive emulsions are excellent in that sharpness is good, development progresses quickly, and a direct positive image with little development temperature dependence is provided. The shape of the tabular grains can be selected from triangles, hexagons, and circles. A regular hexagon having almost equal lengths of six sides as described in U.S. Pat. No. 4,996,137 is a preferred form. In the case of tabular grains, dislocation lines can be observed with a transmission electron microscope. A particle containing no dislocation line, a particle containing several dislocations, or a particle containing many dislocations can be selected according to the purpose. It is also possible to select dislocations introduced linearly or distorted dislocations in a specific direction of the crystal orientation of the grains, or to introduce them all over the grains, or to introduce them only to a specific portion of the grains, for example. The dislocation can be introduced only in the fringe portion of the particle. Dislocation lines can be introduced not only in the case of tabular grains but also in the case of normal grains or irregular grains typified by potato grains. For example, JP-A-63-220238 and JP-A-1-201649 disclose tabular silver halide grains into which dislocations are intentionally introduced.

The preferred ratio between the average grain diameter and the average grain thickness of the tabular grains (hereinafter referred to as grain diameter / thickness) is 2 or more, preferably 3 to 12, and more preferably 5 to 12.
~ 8 is preferred. Here, the average grain diameter of the tabular silver halide grains is an average value of a circle equivalent diameter of two opposing parallel or nearly parallel main planes (diameter of a circle having the same projected area as the main plane). , The average grain thickness represents the average value of the distance between the main planes. Here, the grain diameter / thickness can be obtained by averaging the grain diameter / thickness of all tabular grains, but as a simple method, the ratio of the average diameter of all tabular grains to the average thickness of all tabular grains is obtained. Can also be sought.

The average grain diameter (corresponding to a circle) of the tabular grains is 0.
3 μm or more, preferably 0.3 to 10 μm, more preferably 0.5 to 5.0 μm, and still more preferably 0.5 to 5.0 μm.
3.0 μm. The particle thickness is less than 1.0 μm, preferably 0.05-0.5 μm. Further, an emulsion having a coefficient of variation in grain thickness of 30% or less and high uniformity in thickness is also preferable. Further, grains described in JP-A-63-163451, in which the thickness of grains and the distance between twin planes are specified, are also preferable. In the present invention, the tabular grains account for 50% or more of all the grains in the emulsion containing the tabular grains. It is preferably at least 70%, more preferably at least 90%. The measurement of the grain diameter and grain thickness of tabular grains is described in US Pat.
It can be determined by an electron micrograph of the particles as in the method described in JP-A-34,226.

In the present invention, the tabular grains are preferably monodispersed. The structure and production method of monodisperse tabular grains are described in, for example, JP-A-63-151618.

The silver halide emulsion used in the present invention may be prepared by subjecting grains to a rounding treatment as disclosed in European Patent Nos. 96,727B1 and 64,412B1, or by West German Patent 2,306,447C2. , JP 60
The surface may be modified as disclosed in JP-A-221320. Although a structure having a flat particle surface is generally used, it is sometimes preferable to form irregularities intentionally. JP-A-58-106532 and 60-22132
A method of making a hole in a part of a crystal described in No. 0, for example, a vertex or a center of a face, or US Pat.
Raffle particles described in U.S. Pat. No. 643,966 are examples.

The silver halide grains used in the present invention are:
Research Disclosure (RD) No. 17643
(December 1978), pages 22-23, "I. Emulsion preparation and types" 1
8716 (November 1979), p. 648, ibid. 30
7105 (November 1989), pp. 863-865, and "Physics and Chemistry of Photography" by Grafkid, published by Paul Montell (P. Glafkides Chimie et Pysique Photograhique,
Paul Montel, 1967), "Photographic Emulsion Chemistry" by Duffin, published by Focal Press (GFDuffin, Photograph)
ic Emulsion Chemistry, Focal Press, 1966), "Manufacture and Coating of Photographic Emulsions" by Zelikman et al., published by Focal Press (VLZelikman et al, Making and Coating Pho).
tographic Emulsion, Focal Press, 1964). That is, any of an acidic method, a neutral method, an ammonia method and the like may be used, and a method of reacting a soluble silver salt and a soluble halide may be any one of a one-side mixing method, a simultaneous mixing method, and a combination thereof. Good. A method of forming grains in the presence of excess silver ions (a so-called reverse mixing method) can also be used. As one type of the double jet method, a method in which pAg in a liquid phase in which silver halide is formed is kept constant, that is, a so-called controlled double jet method can be used. According to this method, a silver halide emulsion having a regular crystal form and a nearly uniform grain size can be obtained.
In addition, tabular grains are described by Gatov,
Sunence and Engineering (Gutoff, Photo
graphic Science and Engineering), Vol. 14, 248
257 (1970); U.S. Patent No. 4,434,2.
No. 26, No. 4,414,310, No. 4,433,04
8 and 4,439,520 and British Patent 2,11.
It can be easily prepared by the method described in US Pat.

The silver halide emulsion comprising the above regular grains can be obtained by controlling pAg and pH during grain formation. For details, see Photographic
Sunence and Engineering (Photographic
Science and Engineering), Volume 6, 159-165
Page (1962); Journal of Photographic Science,
12, 242-251 (1964), U.S. Pat. No. 3,655,394 and British Patent 1,413,7.
No. 48. For monodisperse emulsions,
JP-A-48-8600, 51-39027, and 5
Nos. 1-83097, 53-137133, 54-
Nos. 48521, 54-99419, 58-376
No. 35, No. 58-49938, JP-B No. 47-1138
No. 6, US Pat. No. 3,655,394 and British Patent No. 1,413,748.

A method of adding previously precipitated silver halide grains to a reaction vessel for preparing an emulsion, US Pat. Nos. 4,334,012; Is more preferable. These can be used as seed crystals, and are also effective when provided as silver halide for growth. In the latter case, it is preferable to add an emulsion having a small grain size, and the addition method can be selected from a total amount addition at once, an addition in a plurality of times, or a continuous addition. It is also effective in some cases to add particles having various halogen compositions to modify the surface.

A method for converting most or only a part of the halogen composition of silver halide grains by a halogen conversion method is disclosed in US Pat. Nos. 3,477,852 and 4,14.
2,900, EP 273,429, EP 273,
No. 430 and West German Patent No. 3,819,241, which are effective particle forming methods. A solution of a soluble halogen or silver halide grains can be added to convert the silver salt into a sparingly soluble silver salt. It can be selected from methods such as converting at once, converting into a plurality of times, or converting continuously.

In addition to the method of adding a soluble silver salt and a halogen salt at a constant concentration and a constant flow rate for grain growth, British Patent No. 1
469,480; U.S. Pat. No. 3,650,757;
The particle forming method of changing the concentration or changing the flow rate as described in JP-A-4,242,455 is a preferable method. By increasing the concentration or increasing the flow rate, the amount of silver halide to be supplied can be changed by a linear function, a quadratic function, or a more complicated function of the addition time. It is also preferable in some cases to reduce the amount of silver halide supplied as necessary. Further, when adding a plurality of soluble silver salts having different solution compositions or adding a plurality of soluble halide salts having different solution compositions, an addition method of increasing one and decreasing the other is also an effective method. It is. Mixers for reacting a solution of a soluble silver salt and a soluble halide salt are described in U.S. Pat. Nos. 2,996,287, 3,342,605, 3,415,650 and 3,785,777. West German Patent 2,556,885, 2,555,364
Can be used by selecting from the methods described in the above item.

A silver halide solvent is useful for the purpose of accelerating ripening. For example, it is known to have an excess of halogen ions in the reactor to promote ripening. Other ripening agents can also be used. These ripening agents can be incorporated in their entirety in the dispersion medium in the reactor before adding the silver and halide salts, or can be added together with the halide salts, silver salts or peptizers, and added to the reactor. Can also be introduced. As another variant, the ripening agent can be introduced independently during the halide and silver salt addition stage.

As ripening agents other than halogen ions, ammonia, amine compounds, thiocyanate salts,
For example, alkali metal thiocyanate salts, especially sodium and potassium thiocyanate salts, and ammonium thiocyanate salts can be used. The use of thiocyanate ripening agents is disclosed in U.S. Pat. No. 2,222,264.
Nos. 2,448,534 and 3,320,06
No. 9 teaches. Organic thioether compounds (for example, US Pat. Nos. 3,271,157 and 3,574)
Nos. 628, 3,737,313, 3,021,
No. 15, 3,057,724, 3,038,80
Nos. 5, 4,276,374 and 4,297,439
Nos. 3,704,130 and 4,782,013
And compounds described in JP-A-57-104926. ), Thione compounds (for example, JP-A-53-82408).
No. 55-77737, U.S. Pat. No. 4,221,8
No. 63, etc., and compounds described in JP-A-53-144319),
Examples thereof include mercapto compounds and amine compounds (for example, JP-A-54-100717) capable of promoting the growth of silver halide grains described in JP-A-57-202531.

In preparing an emulsion containing tabular grains, a silver salt solution (eg, AgN
A method of increasing the addition rate, amount and concentration of the halide solution (for example, an aqueous KBr solution) and the halide solution (O ₃ aqueous solution) is preferably used. Regarding these methods, for example, British Patent No. 1,335,925, US Pat.
672,900, 3,650,757, 4,2
42,445, JP-A-55-142329, and 55
-158124 can be referred to.
The above-mentioned silver halide solvent is effective for accelerating the ripening.

In some cases, a method of adding a chalcogenide compound during preparation of an emulsion as described in US Pat. No. 3,772,031 is effective. In addition to S, Se, Te, cyanide, thiocyanate, selenocyanate, carbonate,
Phosphates and acetates may be present. These are disclosed in U.S. Pat. Nos. 2,448,060 and 2,628,
167, 3,737,313, 3,772,0
No. 31, Research Disclosure, 134
Vol., June 1975, 13452, and the like.

The internal latent image type silver halide grains used in the present invention preferably have a core / shell structure as described above. A method for producing a shell is disclosed in Japanese Patent Application Laid-Open No. 63-151618.
No. 3,206,316, 3,317,322, 3,761,276, 4,269,927, 3,367,778, etc. Can be In this case, the core / shell molar ratio (molar ratio by weight) is preferably 1/30 to 5/1, more preferably 1/20 to 2/1, and still more preferably 1/2.
0 to 1/1.

In the silver halide emulsion of the present invention, it is preferable to further chemically sensitize the grain surface after coating the shell on the chemically sensitized core grain, but it is preferable that the grain surface is not chemically sensitized. No problem. In general, when the surface of the grains is subjected to chemical sensitization, good reversal performance is obtained in which the maximum density is high. When a chemical sensitization is performed on the grain surface, JP-A-57-136 describes
A polymer as described in No. 41 may coexist. The above chemical sensitization is described in James, The Theory of the Photographic Process, 4th Edition, published by Macmillan, 1977, (TH James, The Theory o
f the Photographic Process, 4th ed., Macmillan, 1
977) on pages 67-76, and can be performed using active gelatin, and can also be performed by Research Disclosure 120, April 1974, 12008; Research Disclosure 34, June 1975.
Moon, 13452, U.S. Pat. Nos. 2,642,361, 3,297,446, 3,772,031, 3,857,711, 3,901,714, and 4,266. No. 018, No. 3, 904, 415
And pAg 5-10, pH 4-8 and temperature 30-35 as described in British Patent 1,315,755.
The reaction can be carried out at 80 ° C. using sulfur, selenium, tellurium, gold, platinum, palladium, iridium, rhodium, osmium, nilium, or a combination of these sensitizers.

Chemical sensitization can be carried out in the presence of a chemical sensitization auxiliary. Compounds known to suppress fog and increase sensitivity in the course of chemical sensitization, such as azaindene, azapyridazine and azapyrimidine, are used as the chemical sensitization aid. Examples of chemical sensitization aids are
U.S. Pat. Nos. 2,131,038 and 3,411,91
4, 3,554,757, JP-A-58-1265.
No. 36, No. 62-253159, and in "Photographic Emulsion Chemistry" by Duffin, pp. 138-143 (Focal Press, 1966).

Japanese Patent Publication No. 58-1410, Moiser
ar) et al., Journal of Photographic Science, Vol. 25, 1977, pp. 19-27. Silver halide emulsions can reduce-sensitize the interior of grains during precipitation. . The following reduction sensitization can also be used as chemical sensitization. US Patent 3,891,
As described in US Pat. Nos. 446 and 3,984,249, reduction sensitization can be performed using, for example, hydrogen, and U.S. Pat.
Using reducing agents as described in US Pat. Nos. 182 and 2,743,183 or low pAg (e.g.
Alternatively, reduction sensitization can be performed by high pH (for example, greater than 8) treatment. Stannous salts as typical reduction sensitizers,
Ascorbic acid and its derivatives, amines and polyamines, hydrazine derivatives, formamidine sulfinic acid,
Silane compounds, borane compounds and the like are known. For the reduction sensitization of the present invention, these known reduction sensitizers can be selected and used, and two or more compounds can be used in combination. Stannous chloride, thiourea dioxide as reduction sensitizer,
Dimethylamine borane, ascorbic acid and its derivatives are preferred compounds. U.S. Pat. No. 3,917,
No. 485 and 3,966,476 can also be applied.

Japanese Patent Application Laid-Open Nos. 61-3134 and 61-3
The sensitization method using an oxidizing agent described in JP-A-136 can also be applied. The oxidizing agent for silver refers to a compound having an action of converting metallic silver into silver ions. In particular, a compound that converts extremely fine silver grains by-produced during the formation process of silver halide grains and the chemical sensitization process into silver ions is effective. The silver ions generated here may form a silver salt that is hardly soluble in water such as silver halide, silver sulfide, silver selenide, or a silver salt that is easily soluble in water such as silver nitrate. Is also good. The oxidizing agent for silver may be inorganic or organic. As the inorganic oxidizing agent, ozone, hydrogen peroxide and its adducts (for example, Na
BO ₂ · H ₂ O ₂ · 3H ₂ O · 2NaCO ₃ · 3H ₂ O
_{2, Na 4 P 2 O 7} · 2H 2 O 2, 2Na 2 SO 4 · H
₂ O ₂ · 2H ₂ O), peroxy acid salt (for example, K ₂ S ₂
O ₈ , K ₂ C ₂ O ₆ , K ₂ P ₂ O ₈ ), peroxy complex compounds (for example, K ₂ [Ti (O ₂ ) C ₂ O ₄ ] · 3H ₂
O, 4K ₂ SO ₄ .Ti (O ₂ ) OH.SO ₄ .2H
Oxygen salts such as ₂ O, permanganate (eg, KMnO ₄ ), chromate (eg, K ₂ Cr ₂ O ₇ ), halogen elements such as iodine and bromine, and perhalates (eg, periodate) Potassium), salts of high valent metals (eg, potassium hexacyanoferrate), and thiosulfonates. Examples of the organic oxidizing agent include quinones such as p-quinone, organic peroxides such as peracetic acid and perbenzoic acid, and compounds that release active halogen (for example, N-bromosuccinimide, chloramine T, chloramine B). ) Is given as an example. Preferred oxidizing agents of the present invention are ozone, hydrogen peroxide and its adducts, halogen elements, inorganic oxidizing agents of thiosulfonates and organic oxidizing agents of quinones. It is a preferred embodiment to use the above-described reduction sensitization and an oxidizing agent for silver in combination. A method of performing reduction sensitization after using an oxidizing agent,
The reverse method or a method in which both coexist simultaneously can be used. These methods can be selectively used in both the grain formation step and the chemical sensitization step.

As a protective colloid used in preparing the emulsion of the present invention, it is advantageous to use gelatin, but other hydrophilic colloids can also be used. For example, gelatin derivatives, graft polymers of gelatin and other polymers, albumin, proteins such as casein; hydroxyethyl cellulose, carboxymethyl cellulose,
Cellulose derivatives such as cellulose sulfates, sodium alginate, sugar derivatives such as starch derivatives; polyvinyl alcohol, polyvinyl alcohol partial acetal, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, Various kinds of synthetic hydrophilic polymer substances such as a single or copolymer such as polyvinyl pyrazole can be used. Examples of gelatin include lime-processed gelatin, acid-processed gelatin, and Bull. Soc. Sci. Photo.
16, P30 (1966). Enzyme-treated gelatin may be used, and hydrolysates or enzymatic degradation products of gelatin may also be used. Gelatin contains many impurity ions, but it is also preferable to use gelatin in which the amount of inorganic impurity ions has been reduced by ion exchange treatment.

The emulsion of the present invention is preferably washed with water for desalting and dispersed in a newly prepared protective colloid. The temperature for water washing can be selected according to the purpose, but is preferably selected in the range of 5 to 50 ° C. The pH at the time of washing can be selected according to the purpose, but is preferably selected from 2 to 10. More preferably, it is in the range of 3 to 8. The pAg at the time of washing can be selected according to the purpose, but is preferably selected from 5 to 10. As a water washing method, a noodle water washing method, a dialysis method using a semipermeable membrane, a centrifugal separation method, a coagulation sedimentation method, or an ion exchange method can be used. In the case of the coagulation sedimentation method, a method using a sulfate, a method using an organic solvent, a method using a water-washing polymer, a method using a gelatin derivative, and the like can be selected.

In the present invention, spectral sensitization can be performed using a sensitizing dye. The sensitizing dyes used include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, and hemioxonol dyes. Specifically, US Pat. No. 4,617,257,
JP-A-59-180550, JP-A-60-140335
No. 61-160739, RD17029 (197
8) 12-13, RD17643 (1978) 2
Sensitizing dyes described on page 3, and the like.

These sensitizing dyes may be used alone or in combination, and the combination of sensitizing dyes is often used particularly for supersensitization. Representative examples are U.S. Pat. Nos. 2,688,545 and 2,9.
77,229, 3,397,060, 3,52
2,052, 3,527,641, 3,61
7,293, 3,628,964 and 3,66
6,480, 3,672,898, 3,67
9,428, 3,703,377, 3,76
9,301, 3,814,609, 3,83
Nos. 7,862, 4,026,707, British Patent Nos. 1,344,281, 1,507,803, JP-B-43-4936, JP-B-53-12375, and JP-A-5
Nos. 2-110618 and 52-109925.

In addition to the sensitizing dye, the emulsion may contain a dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization. (For example, U.S. Pat. Nos. 3,615,613, 3,
No. 615,641, No. 3,617,295, No. 3,6
No. 35,721, No. 2,933,390, No. 3,74
3,510 and JP-A-63-23145). The sensitizing dye may be added to the emulsion at any stage in the preparation of the emulsion which has been known to be useful. Most commonly, it is performed after completion of chemical sensitization but before coating, but US Pat. No. 3,628,969.
No. 4,225,666, the addition of a chemical sensitizer at the same time and the spectral sensitization is carried out simultaneously with the chemical sensitization are also described in JP-A-58-113928. As described above, it can be carried out prior to chemical sensitization, or it can be added before the completion of precipitation of silver halide grains to start spectral sensitization. See also U.S. Pat.
Adding these compounds separately as taught in U.S. Pat. No. 25,666, i.e. adding some of these compounds prior to chemical sensitization and the remainder after chemical sensitization. US Pat. No. 4,183,183 is also possible.
At any time during the formation of silver halide grains, including the method disclosed in No. 756.

The addition amount is 10 mol per mol of silver halide.
^The silver halide grains can be used in an amount of from ^-8 to 10 ^-2 mol. In the case of a more preferable silver halide grain size of 0.2 to 1.2 m, about 5 x 10 ^-5 to 2 x 10 ^-3 mol is more effective.

The coating amount of the photosensitive silver halide used in the present invention is in the range of 1 mg to 10 g / m ² in terms of silver.

In the present invention, various antifoggants and photographic stabilizers can be used for the purpose of preventing a reduction in sensitivity and the occurrence of fog. For example, RD17643
(1978) 24-25, U.S. Patent No. 4,629,
No. 678, azoles and azaindenes, carboxylic acids and phosphoric acids containing nitrogen described in JP-A-59-168442, or mercapto compounds and metal salts thereof described in JP-A-59-111636, −
For example, acetylene compounds described in Japanese Patent No. 87957 can be used. These additives are described in more detail in Research Disclosure Item 17643 (1978),
Item 18716 (November 1979) and Item 30
7105 (November 1989), and the relevant portions are summarized in the table below.

Type of Additive RD17643 RD18716 RD307105 (December 1978) (November 1979) (November 1989) 1 Chemical sensitizer page 23 648 right column 866 page 2 Sensitivity enhancer 648 right column 3 Spectral sensitizer, page 23-24 page 648, right column 866-868 Supersensitizer-page 649, right column 4 Brightener 24 page 647 page 868 5 Fog prevention 24-25 page 649, right column 868- Page 870 Agent, stabilizer 6 Light absorber, pages 25 to 26 Page 649 Right column Page 873 Filter 〜 Page 650 Left column Dye, UV absorber 7 Stain Page 25 Right column 650 Page Left column 872 Inhibitor ~ Right column 8 Dye image page 25 page 650 left column page 872 Stabilizer 9 hardener 26 page 651 page left column 874-875 page 10 Binder page 26 Same as above 873-874 11 plasticizer, page 27 page 650 right column page 876 Lubrication Agent 12 Coating aid, pages 26 to 27 Same as above, pages 875 to 876 Surfactant 13 Statistics, page 27 Same as above, pages 876 to 877 Inhibitor 14 Matsuto 878 to 879

Hereinafter, each component included in the present invention will be sequentially described. I. Photosensitive Sheet A) Support The support for the photosensitive sheet used in the present invention may be any smooth transparent support usually used for photographic photosensitive materials, and examples thereof include cellulose acetate, polystyrene, polyethylene terephthalate, and polycarbonate. It is preferable to provide an undercoat layer. The support usually preferably contains a trace amount of a dye or a pigment such as titanium oxide to prevent light piping. Support thickness is 50
−350 μm, preferably 70-210 μm, more preferably 80-150 μm. If necessary, a layer for curl balance may be provided on the back side of the support.
An oxygen barrier layer described in JP-A-6-78833 can be provided.

B) Image Receiving Layer The dye receiving layer used in the present invention contains a mordant in a hydrophilic colloid. This may be a single layer or a multilayer structure in which mordants having different mordant powers are applied in layers. This is described in JP-A-61-25255.
1. As the mordant, a polymer mordant is preferable. Polymer mordant is a polymer containing secondary and tertiary amino groups, a polymer having a nitrogen-containing heterocyclic moiety,
And a polymer containing a quaternary cation with a molecular weight of 5,
More than 000, particularly preferably more than 10,000. The coating amount of the mordant is generally 0.5 to 1.
0 g / m ² is preferably particularly preferably 1.0 to 5.0 g / m ² is 2 to 4 g / m ^2. As the hydrophilic colloid used in the image receiving layer, gelatin, polyvinyl alcohol, polyacrylamide, polyvinylpyrrolidone and the like are used, and gelatin is preferable. In the image receiving layer, JP-B-62-3
Nos. 0620 and 62-30621, JP-A-62-21
No. 5,272, can be incorporated.

C) White Reflective Layer The white reflective layer forming the white background of the color image usually contains a white pigment and a hydrophilic binder. As white pigments for the white reflective layer, barium sulfate, zinc oxide, barium stearate,
Silver flakes, silicates, alumina, zirconium oxide, sodium zirconium sulfate, kaolin, mica, titanium dioxide and the like are used. Further, non-film-forming polymer particles made of styrene or the like are also used. These may be used alone or as a mixture as long as the desired reflectance is obtained. A particularly useful white pigment is titanium dioxide. The whiteness of the white reflective layer is
The light reflectance is desirably 70% or more, although it varies depending on the type of the pigment, the mixing ratio of the pigment and the binder, and the amount of the pigment applied. Generally, as the amount of the pigment applied increases, the whiteness improves, but when the image forming dye diffuses through this layer, the pigment becomes resistant to the diffusion of the dye,
It is desirable to have an appropriate coating amount. 5 titanium dioxide
４０40 g / m ² , preferably 10-25 g / m ² ,
A white reflective layer having a light reflectance of 78 to 85% for light having a wavelength of 540 mm is preferred. Titanium dioxide can be selected from various commercially available brands. Among them, it is particularly preferable to use rutile type titanium dioxide. Many commercially available products are surface-treated with alumina, silica, zinc oxide, or the like, and a surface treatment amount of 5% or more is desirable to obtain high reflectance. Examples of commercially available titanium dioxide include those described in Research Disclosure No. 15162, besides Ti-pure R931 manufactured by DuPont. As a binder for the white reflective layer, an alkali-permeable polymer matrix such as gelatin,
Polyvinyl alcohol and hydroxyethyl cellulose,
Cellulose derivatives such as carboxymethylcellulose can be used. A particularly desirable binder for the white reflective layer is gelatin. The ratio of white pigment to gelatin is 1/1 to 1
The ratio is 20/1 (weight ratio), preferably 5/1 to 10/1 (weight ratio). In the white reflective layer, there is JP-B-62-306.
It is preferable to incorporate an anti-fading agent such as No. 20 or 62-30621.

D) Light-shielding layer A light-shielding layer containing a light-shielding agent and a hydrophilic binder is provided between the white reflective layer and the photosensitive layer. As the light-shielding agent, any material having a light-shielding function is used, and carbon black is preferably used. U.S. Pat.
Degradable dyes described in US Pat. No. 5,966 or the like may be used. As the binder for coating the light-blocking agent, any binder capable of dispersing carbon black may be used, and gelatin is preferred. As carbon black raw materials, for example, Donn
el Voet "Carbon Black" Marcel Dekker, Inc. (197
Any method such as the channel method, thermal method and furnace method described in 6) can be used.
The particle size of the carbon black is not particularly limited, but is 9
It is preferably from 0 to 1800 °. The addition amount of the black pigment as a light-shielding agent may be adjusted according to the sensitivity of the photosensitive material to be shielded from light, but is preferably about 5 to 10 in optical density.

E) Photosensitive Layer In the present invention, a photosensitive layer comprising a silver halide emulsion layer combined with a dye image-forming substance is provided above the light-shielding layer. The components will be described below. (1) Dye image-forming substance The dye image-forming substance used in the present invention is a non-diffusible compound which releases a diffusible dye (may be a dye precursor) in connection with silver development, or has a diffusivity of itself. Is changing, and the theory of the photographic process “The Theory
All of these compounds can be represented by the following general formula (I): DYE-Y (I) wherein DYE represents a dye or a precursor, Y
Represents a component that gives a compound having a different diffusibility from the core compound under alkaline conditions. According to the function of Y, the compound is roughly classified into a negative type compound which becomes diffusible in a silver developed portion and a positive type compound which becomes diffusible in an undeveloped portion. Specific examples of the negative type Y include those which oxidize as a result of development and are cleaved to release a diffusible dye. Specific examples of Y are described in US Pat. No. 3,928,
No. 312, No. 3,993,638, No. 4,076,5
No. 29, No. 4, 152, 153, No. 4, 055, 42
No. 8, 4,053, 312, 4,198,235
Nos. 4,179,291 and 4,149,892
No. 3,844,785, No. 3,443,943
Nos. 3,751,406 and 3,443,939
Nos. 3,443,940 and 3,628,952
Nos. 3,980,479 and 4,183,753
No. 4,142,891, No. 4,278,750
Nos. 4,139,379 and 4,218,368
No. 3,421,964, 4,199,355
No. 4,199,354, 4,135,929
No. 4,336,322, 4,139,389
No. JP-A-53-50736 and JP-A-51-104343.
No. 54-130122, No. 53-110827
Nos. 56-12642, 56-16131, 57-4043, 57-650, and 57-207
No. 35, No. 53-69033, No. 54-130927
Nos. 56-164342 and 57-119345. Among the Y's in the negative dye-releasing redox compound, a particularly preferred group is an N-substituted sulfamoyl group (an N-substituent is a group derived from an aromatic hydrocarbon ring or a hetero ring). The representative groups of Y are illustrated below, but are not limited thereto.

[0057]

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[0058]

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For the positive type compounds, see Angev. Chem. Inst. Ed. Engl., 22, 191 (1).
982). Specific examples include compounds (dye developing agents) which are initially diffusible under alkaline conditions but are oxidized by development to become non-diffusible. US Pat. No. 2,986,360 describes Y useful for compounds of this type.
No. 6 is typical. Another type is a type in which a diffusible dye is released by, for example, self-cyclization under alkaline conditions, but the dye is substantially not released when oxidized during development. For a specific example of Y having such a function, see US Pat.
0,479, JP-A-53-69033 and JP-A-54-130.
927, U.S. Patents 3,421,964 and 4,199,
355. Another type does not release the dye itself, but releases the dye when reduced. Compounds of this type can be used in combination with an electron donor to release the diffusible dye imagewise by reaction with the remaining electron donor imagewise oxidized by silver development. For atomic groups having such a function, see, for example, US Pat. Nos. 4,183,753 and 4,1
42,891, 4,278,750, 4,139,
379, 4,218,368, JP-A-53-1108.
27, US Patents 4,278,750 and 4,356,2
49, 4,358,535, JP-A-53-11082
7, 54-130927, 56-164342, Published Technical Report 87-6199, European Patent Publication 220746A2
And so on. Specific examples are shown below,
However, it is not limited only to these.

[0060]

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[0061]

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When a compound of this type is used, it is preferably used in combination with a diffusion-resistant electron donating compound (known as an ED compound) or a precursor thereof. Examples of ED compounds include, for example, US Pat.
Nos. 263,393 and 4,278,750;
No. 6-138736. Specific examples of other types of dye image-forming substances include the following.

[0063]

Embedded image

The details are described in US Pat. Nos. 3,719,489 and 4,098,783. On the other hand, specific examples of the dye represented by DYE in the above general formula are described in the following documents. Examples of yellow dyes: U.S. Pat. Nos. 3,597,200, 3,309,199, 4,013,633, 4,245,028, 4,156,609 and 4,139. JP-A-51-114930, 383, 4,195,992, 4,148,641, 4,148,643 and 4,336,322.
No. 56-71072: Research Disclosure 1763
No. 0 (1978) and No. 16475 (1977). Examples of magenta dyes: U.S. Pat. Nos. 3,453,107, 3,544,545, 3,932,380, 3,931,144, 3,932,308, and 3,954 No. 4,476, 4,233,237, 4,255,509, 4,250,246, 4,142,891, 4,207,104, 4,287,292. No .: JP-A-52-106,727
No. 52-106727, No. 53-23,628
Nos. 55-36,804 and 56-73,057
No. 56-71060 and No. 55-134. Examples of cyan dyes: U.S. Pat. Nos. 3,482,972, 3,929,760, 4,013,635, 4,268,625, 4,171,220 and 4,242 No. 4,435,891, No. 4,195,994, No. 4,147,544, No. 4,148,642; British Patent 1,551,138;
JP-A Nos. 54-99431, 52-8827, and 5
3-47823, 53-143323, 54-
No. 99431, No. 56-71061; European Patent (EPC) No. 53,037, No. 53,040; Research
Disclosure 17,630 (1978) and 1
No. 6,475 (1977). These compounds are disclosed in JP-A-62-215272, 1
It can be dispersed by the method described on pages 44 to 146. These dispersions are described in JP-A-62-215,272.
No. 137-144 may be included.

(2) Silver halide emulsion The silver halide emulsion of the present invention is as described above.

(3) Composition of photosensitive layer To reproduce a natural color by the subtractive color method, the above-mentioned dye which provides a dye having a selective spectral absorption in the same wavelength range as the emulsion spectrally sensitized by the above-mentioned spectral sensitizing dye is used. A photosensitive layer comprising at least two of the combination with an image forming substance is used. The emulsion and the dye image-forming substance may be coated as separate layers,
Alternatively, they may be mixed and applied as a single layer. When the dye image-forming substance is coated and has absorption in the spectral sensitivity range of the emulsion combined therewith, a separate layer is preferred. The emulsion layer may be composed of a plurality of emulsion layers having different sensitivities, and an arbitrary layer may be provided between the emulsion layer and the dye image forming substance layer. For example, a layer containing a nucleation development accelerator described in JP-A-60-173541, JP-B-60-15
267 can be provided to increase the color image density, or a reflective layer can be provided to enhance the sensitivity of the photosensitive element. The reflective layer is a layer containing a white pigment and a hydrophilic binder. Preferably, the white pigment is titanium oxide and the hydrophilic binder is gelatin. The coating amount of titanium oxide is 0.1 g / m ^{2 to} 8 g / m ² , preferably 0.2 g / m ²
/ M ^{2 to 4} g / m ² . This is a preferred embodiment of the present invention.
Examples of the reflective layer are described in JP-A-60-91354. In a preferred multilayer structure, a combination unit of a blue-sensitive emulsion, a combination unit of a green-sensitive emulsion, and a combination unit of a red-sensitive emulsion are sequentially arranged from the exposure side. Arbitrary layers can be provided between the emulsion layer units as needed. In particular, it is preferable to provide an intermediate layer in order to prevent an unfavorable effect of the development effect of one emulsion layer on other emulsion layer units.
When a developer is used in combination with a non-diffusible dye image-forming substance, the intermediate layer preferably contains a non-diffusible reducing agent in order to prevent the diffusion of the oxidized product. Specific examples thereof include non-diffusible hydroquinone, sulfonamidophenol, and sulfonamidonaphthol. More specifically, Japanese Patent Publication Nos. 50-21249 and 50-23813, JP-A-49-106329 and JP-A-49-129535, U.S. Pat. Nos. 2,336,327, 2,360,290,
403,721, 2,544,640, 2,73
2,300, 2,782,659, 2,937,0
86, 3,637,393, 3,700,453,
It is described in British Patent 557,750, JP-A-57-24949, and JP-A-58-21249. The dispersing methods are described in JP-A-60-238831 and JP-B-60-88.
18978. Japanese Patent Publication 55-7576
In the case of using a compound capable of releasing a diffusible dye by silver ions as described in (1), it is preferable to include a compound that captures silver ions in the intermediate layer. In the present invention, an anti-irradiation layer, a UV absorber layer, a protective layer and the like are provided as needed.

F) Peeling Layer In the present invention, a peeling layer can be provided, if necessary, to peel off the photosensitive sheet in the unit at an arbitrary place after processing. Therefore, this release layer must be easily peelable after the treatment. As a material for this, for example,
JP-A-47-8237, JP-A-59-220727, JP-A-59-229555, JP-A-49-4653, U.S. Pat. Nos. 3,220,835 and 4,359,518, and JP-A-49-4334. Nos. 56-65133, 45
-24075, U.S. Pat. Nos. 3,227,550, 2,759,825, 4,401,746, and 4,366,227 can be used. One specific example is a water-soluble (or alkali-soluble) cellulose derivative. For example, hydroxyethyl cellulose, cellulose acetate-phthalate, plasticized methyl cellulose, ethyl cellulose, cellulose nitrate, carboxymethyl cellulose, and the like. As another example, various natural polymers,
For example, there are alginic acid, pectin, gum arabic and the like. Various modified gelatins such as acetylated gelatin and phthalated gelatin can also be used. Still another example is a water-soluble synthetic polymer. For example,
Examples thereof include polyvinyl alcohol, polyacrylate, polymethyl methacrylate, polybutyl methacrylate, and a copolymer thereof. The release layer may be a single layer or, for example, disclosed in JP-A-59-220727,
It may be composed of a plurality of layers as described in Japanese Patent Application No. 0-60642.

II. In the present invention, a layer having a neutralizing function (neutralizing layer and neutralization timing) is used to uniformly spread the processing solution on the photosensitive element and neutralize the alkali after processing to stabilize the image. Layer) having a transparent cover sheet.

G) Support The support for the cover sheet used in the present invention may be any smooth transparent support usually used for photographic light-sensitive materials, and examples thereof include cellulose acetate, polystyrene, polyethylene terephthalate, and polycarbonate. ,
It is preferable to provide an undercoat layer. The support preferably contains a trace amount of a dye to prevent light piping.

H) Layer Having Neutralizing Function The layer having a neutralizing function used in the present invention is a layer containing an acidic substance in an amount sufficient to neutralize the alkali introduced from the treatment composition. Accordingly, a multilayer structure including layers such as a neutralization rate control layer (timing layer) and an adhesion strengthening layer may be used. Preferred acidic substances are those containing an acidic group having a pKa of 9 or less (or a precursor group that provides such an acidic group by hydrolysis), and more preferably oleic acid described in US Pat. No. 2,983,606. Higher fatty acids such as US Pat. No. 3,362,819
Of acrylic acid, methacrylic acid or maleic acid and their partial esters or acid anhydrides as disclosed in US Pat. Ester copolymers;
U.S. Pat. No. 4,139,383 and Research Disclosure No. 16102 (197
Latex type acidic polymers as disclosed in 7) can be mentioned. In addition, U.S. Pat.
8,493, JP-A Nos. 52-153,739 and 53
-1,023, 53-4,540, 53-4,
No. 541 and Nos. 53-4, 542, and the like. Specific examples of the acidic polymer include a copolymer of ethylene, vinyl acetate, a vinyl monomer such as vinyl methyl ether, and maleic anhydride, and n-
Butyl ester, a copolymer of butyl acrylate and acrylic acid, cellulose, acetate hydrogendiphthalate, and the like. The polymer acid can be used as a mixture with a hydrophilic polymer. Such polymers include polyacrylamide, polymethylpyrrolidone, polyvinyl alcohol, (including partially saponified), carboxymethylcellulose, hydroxymethylcellulose,
Hydroxyethyl cellulose, polymethyl vinyl ether and the like. Among them, polyvinyl alcohol is preferred. Further, a polymer other than the hydrophilic polymer, such as cellulose acetate, may be mixed with the polymer acid. The amount of the polymer acid applied is controlled by the amount of alkali developed on the photosensitive element. The equivalent ratio of the polymer acid to the alkali per unit area is preferably from 0.9 to 2.0. If the amount of the polymer acid is too small, the hue of the transfer dye is changed or stain is generated on a white background portion. If the amount is too large, inconveniences such as a change in hue and a decrease in light resistance are caused. A more preferred equivalent ratio is 1.0-1.3. If the amount of the hydrophilic polymer to be mixed is too large or too small, the quality of the photograph is deteriorated. The weight ratio of the hydrophilic polymer to the polymer acid is 0.1-10, preferably 0.3-3.
0. Additives can be incorporated into the layer having a neutralizing function of the present invention for various purposes. For example, hardeners well known to those skilled in the art can be added to harden this layer, and polyhydric hydroxyl compounds such as polyethylene glycol, polypropylene glycol, glycerin, etc. can be added to improve the brittleness of the film. In addition, if necessary, an antioxidant, a fluorescent whitening agent, a development inhibitor and a precursor thereof may be added. Timing layer used in combination with the neutralizing layer, for example, gelatin, polyvinyl alcohol, partially acetalized polyvinyl alcohol, cellulose acetate, partially hydrolyzed polyvinyl acetate,
Polymers that lower alkali permeability such as, for example; latex polymers that are made by copolymerizing a small amount of a hydrophilic comonomer such as acrylic acid monomer to increase the activation energy of alkali permeation; polymers that have lactone rings are useful It is. In particular, Japanese Patent Application Laid-Open No. 54-1363
No. 28, U.S. Pat. Nos. 4,267,262 and 4,00
No. 9,030, 4,029,849, etc .; Timing Layer Using Cellulose Acetate;
4-128335, 56-69,629, 57
-6,843, U.S. Pat. Nos. 4,056,394, 4,061,496, 4,199,362, 4,250,243, 4,256,827 and 4, Latex polymers prepared by copolymerizing a small amount of a hydrophilic comonomer such as acrylic acid disclosed in US Pat. No. 268,604; polymers having a lactone ring disclosed in U.S. Pat. No. 4,229,516; No. 56-25735, No. 56-97346, No. 57-
No.6842, European Patent (EP) 31,957A1
The polymers disclosed in Nos. 37,724A1 and 48,412A1 are particularly useful. In addition, those described in the following documents can also be used. US Patent 3,42
Nos. 1,893, 3,455,686 and 3,57
5,701, 3,778,265, 3,78
5,815, 3,847,615, 4,08
8,493, 4,123,275, 4,14
8,653, 4,201,587, 4,28
8,523, 4,297,431, West German Patent Application (OLS) 1,622,936, 2,162,27
No. 7, Research Disclosure 15, 162 No. 151
(1976) The timing layer using these materials can be used as a single layer or as a combination of two or more layers. In addition, for example, US Pat. No. 4,009,029, West German Patent Application (OLS) 2,
Nos. 913,164 and 3,014,672;
Development inhibitors and / or precursors thereof disclosed in JP-A-4-155837, JP-A-55-138745, etc .; hydroquinone precursors disclosed in U.S. Pat. No. 4,201,578; and other useful photographic additives. It is also possible to incorporate the agent or its precursor. Furthermore, as a layer having a neutralizing function,
By providing an auxiliary neutralizing layer as described in JP-A-63-168648 and JP-A-63-168649, there is an effect in that a change in transfer density over time after processing is reduced.

I) Others In addition to the layer having a neutralizing function, a layer having an auxiliary function may include a back layer, a protective layer, a capture mordant layer, a filter dye layer, and the like. The back layer is provided for adjusting curl and imparting slipperiness. Filter dyes may be added to this layer. The protective layer is mainly used for preventing adhesion to the back surface of the cover sheet and adhesion to the protective layer of the photosensitive material when the photosensitive material and the cover sheet are overlapped. The capture mordant layer can prevent delay of image completion time and deterioration of sharpness by capturing the dye diffused to the alkali treatment composition side. Usually, a dye capturing layer is provided on the outermost layer of the cover sheet. The dye-capturing layer contains a polymer mordant in a hydrophilic colloid similarly to the above-mentioned dye image-receiving layer.
-282253. The sensitivity of the photosensitive layer can be adjusted by adding a dye to the cover sheet. The filter dye may be directly added to the cover sheet support or a layer having a neutralizing function, and further to the back layer, the protective layer, the capture mordant layer, or a single layer may be provided. . Japanese Patent Application Laid-Open No. 62-215272 discloses a photosensitive sheet, a cover sheet, or an alkali treatment composition.
Development accelerator described on page 91, hardener described on pages 146 to 155, surfactant described on pages 201 to 210, 210 to 22
Fluorine-containing compounds described on page 2, thickeners described on pages 225 to 227, antistatic agents described on pages 227 to 230, 230-2
It can contain a polymer latex described on page 39, a matting agent described on page 240, and the like.

III. Alkali processing composition The processing composition used in the present invention is uniformly spread on the photosensitive element after exposure of the photosensitive element, and is disposed on the back of the support or on the side opposite to the processing solution of the photosensitive layer to form a pair with the light shielding layer. Thus, the photosensitive layer is completely shielded from external light, and at the same time, the photosensitive layer is developed by the contained components. For this purpose, the composition contains an alkali, a thickener, a light-blocking agent, a developer, and further, a development accelerator for controlling development, a development inhibitor, an antioxidant for preventing deterioration of the developer, and the like. It contains. The composition always contains a light-shielding agent. The alkali is sufficient to adjust the pH of the solution to 12 to 14, and includes an alkali metal hydroxide (eg, sodium hydroxide, potassium hydroxide, lithium hydroxide) and an alkali metal phosphate (eg, potassium phosphate). , Guanidines, and quaternary amine hydroxides (eg, tetramethylammonium hydroxide, etc.), among which potassium hydroxide and sodium hydroxide are preferred. The thickener is required to spread the processing solution uniformly and to maintain the close contact between the photosensitive layer and the cover sheet. For example, alkali metal salts of polyvinyl alcohol, hydroxyethyl cellulose and carboxymethyl cellulose are used, and preferably, hydroxyethyl cellulose and sodium carboxymethyl cellulose are used. As the light-shielding agent, any dye or pigment can be used as long as the light-shielding agent does not diffuse to the dye image-receiving layer to produce stain, or a combination thereof. A typical example is carbon black. Preferred developing agents can be used as long as they cross-oxidize the dye image-forming substance and do not substantially cause stain when oxidized. Such developing agents may be used alone or in combination of two or more, and may be used in a precursor form. These developing agents may be contained in an appropriate layer of the photosensitive element, or may be contained in an alkaline processing solution. Specific compounds include aminophenols and pyrazolidinones, and among them, pyrazolidinones are particularly preferable because they generate less stain. For example, 1-phenyl-3-pyrazolidinone, 1-p-tolyl-4,4-dihydroxymethyl-3
-Pyrazolidinone, 1- (3'-methyl-phenyl)-
4-methyl-4-hydroxymethyl-3-pyrazolidinone, 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidinone, 1-p-tolyl-4-methyl-
4-hydroxymethyl-3-pyrazolidinone, and the like.

[0073]

The present invention will be described in detail with reference to the following examples, but the present invention is not limited to these examples. Example 1 First, a method for preparing a silver halide emulsion will be described. Emulsion A-1 (octahedral internal latent image type direct positive emulsion-for comparison) 1000 cc of an 8% by weight aqueous gelatin solution containing 13 g of potassium bromide and 0.05 g of 1,8-dihydroxy-3,6-dithiooctane While maintaining the temperature at 75 ° C., a 0.4 M aqueous solution of silver nitrate and a 0.4 M aqueous solution of potassium bromide were adjusted to a pBr of 1.3 by a control double jet method.
While adjusting the rate of addition of the aqueous potassium bromide solution to 0, 300 cc of an aqueous silver nitrate solution was added over 40 minutes. When the addition is completed, the average particle diameter (equivalent sphere diameter) is about 0.1.
Octahedral silver bromide crystals (hereinafter referred to as core grains) with a uniform grain size of 8μ were produced. Next, 0.7 mg of sodium thiosulfate and 0.1 mg of potassium chloroaurate were added to the silver bromide particles.
4 mg (all added in an aqueous solution) and added at 75 ° C.
A chemical sensitization treatment was performed by heating for minutes. In the same manner as in the preparation of the core particles, a 0.8 M aqueous solution of silver nitrate and a 0.8 M aqueous solution of potassium bromide were added to the chemically sensitized core particles by the control double jet method while maintaining the temperature at 75 ° C. While controlling the rate of addition of the aqueous potassium bromide solution so that the value became 1.30, 740 cc of an aqueous silver nitrate solution was added over 60 minutes to form a shell.
This emulsion was washed with water by a conventional flocculation method,
The average particle size (sphere equivalent diameter) is about 1.4μ by adding gelatin.
(Hereinafter referred to as internal latent image type core / shell particles). Next, 0.4 mg of sodium thiosulfate and 20 mg of poly (N-vinylpyrrolidone) per mole of silver were added to the internal latent image type core / shell emulsion, and the mixture was heated at 60 ° C. for 60 minutes to form a chemical compound on the grain surface. After sensitization, an octahedral internal latent image type direct positive emulsion was prepared. Emulsion B (Octahedral internal latent image type direct positive emulsion) A 1000 wt.% Aqueous gelatin solution containing 13 g of potassium bromide and 0.05 g of 1,8-dihydroxy-3,6-dithiooctane was heated at a temperature of 1000 cc. While maintaining the temperature at 75 ° C., a 0.4 M aqueous solution of silver nitrate and a 0.4 M aqueous solution of potassium bromide were adjusted to a pBr of 1.3 by a control double jet method.
While adjusting the addition rate of the aqueous potassium bromide solution so as to become 0, 300 cc of an aqueous silver nitrate solution was added over 23 minutes. When the addition is completed, the average particle diameter (equivalent sphere diameter) is about 0.1.
Octahedral silver bromide crystals (hereinafter referred to as core grains) with a uniform grain size of 45μ were produced. Next, 0.22 mg of sodium thiosulfate and 0.12 mg of potassium chloroaurate (all added in an aqueous solution) were added to the silver bromide particles.
For 80 minutes to perform a chemical sensitization treatment.
In the same manner as in the preparation of the core particles, a 0.8 M aqueous solution of silver nitrate and a 0.8 M aqueous solution of potassium bromide were added to the chemically sensitized core particles by the control double jet method while maintaining the temperature at 75 ° C. While controlling the rate of addition of the aqueous potassium bromide solution so that the value became 1.30, 740 cc of an aqueous silver nitrate solution was added over 35 minutes to form a shell. This emulsion is washed with water by a conventional flocculation method, and gelatin is added to the emulsion to form an octahedral silver bromide crystal having an average particle diameter (equivalent sphere diameter) of about 0.8 μm (hereinafter referred to as an internal latent image type). Core / shell particles). Next, 0.1% per mole of silver was added to the internal latent image type core / shell emulsion.
3 mg of sodium thiosulfate and 6.5 mg of poly (N-vinylpyrrolidone) were added, and heated at 60 ° C. for 60 minutes to chemically sensitize the grain surface to prepare an octahedral internal latent image type direct positive emulsion. . Emulsions A-2 to A-8 (Comparative Examples), A-9 to A-11 (Invention) At the time of shell formation, the metal complexes shown in Table 1 below were added to each emulsion in the amounts shown in Table 1 per mole of silver nitrate. Emulsions A-2 to 11-11 were exactly the same as Emulsion A-1, except that
Was prepared.

[0074]

[Table 1]

Next, a comparative photosensitive element (sample 101) having the composition shown in Table 2 below was prepared using Emulsion A-1.

[0076]

[Table 2]

[0077]

[Table 3]

[0078]

[Table 4]

[0079]

[Table 5]

[0080]

Embedded image

[0081]

Embedded image

[0082]

Embedded image

[0083]

Embedded image

[0084]

Embedded image

[0085]

Embedded image

The cover sheet was prepared as follows. The following layers were coated on a transparent polyethylene terephthalate support containing a light-piping preventing dye subbed with gelatin. (1) Acrylic acid-butyl acrylate (average molecular weight: 8: 2) copolymer having an average molecular weight of 50,000 was used at 10.4 g / m ² and 1,4 g / m ² .
4-bis (2,3-epoxypropoxy) -butane
Neutralization layer containing 1 g / m ² . (2) 4.3 g / m ^{2 of} acetylcellulose having a degree of acetylation of 51%,
Neutralization timing layer containing 0.2 g / m ² of poly (methyl vinyl ether-co-monomethyl maleate). (3) Styrene-butyl acrylate-acrylic acid-N-methylolacrylamide in a weight ratio of 49.7 / 42.3 /
A polymer latex obtained by emulsion polymerization at a ratio of 4/4 and a polymer latex obtained by emulsion polymerization of methyl methacrylate / acrylic acid / N-methylolacrylamide at a weight ratio of 9: 3: 3: 4 have a solid fraction of 6: 4. And a layer containing 2.5 g / m ^{2 of the} total solid content. (4) A layer containing 1 g / m ² of gelatin.

The formulation of the alkali treatment composition is shown below. 1-p-tolyl-4-hydroxymethyl-4-methyl-3-pyrazolidone 10.0 g methylhydroquinone 0.18 g 5-methylbenzotriazole 3.0 g sodium sulfite (anhydrous) 0.2 g benzyl alcohol 1.5 cc carboxymethylcellulose Na Salt 58 g Carbon black 150 g Potassium hydroxide (28% aqueous solution) 200 cc Water 680 cc Each of the treatment solutions having the above composition was filled in 0.8 g portions into a "container which can be broken under pressure".

Next, Samples 102 to 111 shown in Table 3 were prepared by changing the emulsions of the seventh, thirteenth and nineteenth layers to emulsions A-2 to A-11 shown in Table 1.

[0089]

[Table 6]

After exposing the photosensitive elements 101 to 111 from the emulsion layer side through a gray continuous wedge, the photosensitive elements 101 to 111 were superposed on the cover sheet, and the above processing solution was applied between the two materials.
It was developed using a pressure roller to a thickness of 5 μm. The treatment was performed at 25 ° C., and the transfer density was measured with a color densitometer after 10 minutes. Table 4 shows the results. However, the midpoint sensitivity shown here is a reciprocal value of the exposure amount that gives an intermediate density between the maximum density and the minimum density, expressed as a relative value with respect to the reference sample. The low-density sensitivity is represented by a reciprocal value of an exposure amount giving a density corresponding to the minimum density + 0.2 as a relative value with respect to a reference sample.

[0091]

[Table 7]

From Table 7, it can be seen that in the case of the present invention, both the mid-point sensitivity and the low density sensitivity are high, and the low density portion is hardened. Example 2 First, a method for preparing a silver halide emulsion will be described. Emulsion C-1 (hexagonal tabular internal latent image type direct positive emulsion-for comparison) 2 M silver nitrate aqueous solution containing gelatin in 1 liter of 0.7% by weight gelatin aqueous solution containing 0.04 M potassium bromide And 2M aqueous potassium bromide solution containing gelatin and 25 cc of each were simultaneously mixed for 1 minute by the double jet method while vigorously stirring. During this time, the aqueous gelatin solution was 3
It was kept at 0 ° C. After the addition, the temperature was raised to 75 ° C., and 300 cc of a 10% by weight gelatin solution was added. Next, 20 cc of a 1M silver nitrate aqueous solution was added over 5 minutes, and then a 25% by weight aqueous ammonia solution was added, followed by ripening at 75 ° C. After the ripening, ammonia was neutralized, and then a 1M aqueous solution of silver nitrate and a 1M aqueous solution of potassium bromide were accelerated at an accelerated flow rate with a pBr of 2.5 (the flow rate at the end was 4 times the flow rate at the start).
Times) and added by the double jet method. (The amount of the used silver nitrate aqueous solution was 600 cc.) The particles thus formed (hereinafter referred to as core particles) were washed with water by a conventional flocculation method, gelatin was added, and 800 g of a hexagonal flat plate was added. Core particles were obtained. The obtained hexagonal tabular core grains had an average projected area circle equivalent diameter of 1.0 μm and an average thickness of 0.21 μm, and 95% of the total projected area was occupied by the hexagonal tabular grains. Next, 750 cc of water and 30 g of gelatin were added to 250 g of the hexagonal tabular core emulsion, and the temperature was raised to 75 ° C., followed by 1,8-dihydroxy-3,
0.5 g of 6-dithiooctane, 0.1 g of sodium thiosulfate.
8 mg and 0.4 mg of potassium chloroaurate (all added in an aqueous solution) were added, and the mixture was heated at 75 ° C. for 80 minutes to perform a chemical sensitization treatment. Next, a 2M aqueous solution of silver nitrate and a 2.5M aqueous solution of potassium bromide were added to the chemically sensitized core particles in the same manner as in the preparation of the core particles at an accelerated flow rate (when the flow rate at the end was At a flow rate of 5 times). (The amount of the used silver nitrate aqueous solution was 810 cc.) The emulsion was washed with water by a conventional flocculation method, and gelatin was added. Thus, a hexagonal tabular internal latent image type core / shell emulsion was obtained.
The obtained hexagonal tabular grains have an average projected area circle equivalent diameter of 2.3 μm, an average thickness of 0.34 μm, an average volume size of 1.4 (μm) ³ and 88% of the total projected area are hexagonal tabular grains. Occupied by particles. Next, the hexagonal tabular internal latent image type core / shell emulsion was added in an amount of 0.45 / mol silver.
mg of sodium thiosulfate and 15 mg of poly (N-vinylpyrrolidone) were added, and heated at 60 ° C. for 60 minutes to chemically sensitize the grain surface to prepare a hexagonal tabular internal latent image type direct positive emulsion. Emulsions C-2 to C-8 (Comparative Example), C-9 to C-11 (Invention) At the time of shell formation, the metal complexes shown in Table 5 below were added to each emulsion in the amounts shown in Table 5 per mole of silver nitrate. Emulsions C-2 to C-11 were exactly the same as Emulsion C-1, except that
Was prepared.

[0093]

[Table 8]

Next, a comparative photosensitive element (sample 201) having the composition shown in Table 6 below was prepared using Emulsion C-1.

[0095]

[Table 9]

[0096]

[Table 10]

[0097]

[Table 11]

[0098]

[Table 12]

Next, Samples 202 to 211 shown in Table 7 were prepared by changing the emulsions of the seventh, thirteenth, and nineteenth layers to emulsions C-2 to C-11 shown in Table 5.

[0100]

[Table 13]

After exposing the photosensitive elements 201 to 211 from the emulsion layer side through a gray continuous wedge, the photosensitive elements 201 to 211 were superposed on the cover sheet, and the above processing solution was applied between the two materials.
It was developed using a pressure roller to a thickness of 5 μm. The treatment was performed at 25 ° C., and the transfer density was measured with a color densitometer after 10 minutes. Table 8 shows the results. However, the midpoint sensitivity shown here is a reciprocal value of the exposure amount that gives an intermediate density between the maximum density and the minimum density, expressed as a relative value with respect to the reference sample. The low-density sensitivity is represented by a reciprocal value of an exposure amount giving a density corresponding to the minimum density + 0.2 as a relative value with respect to a reference sample.

[0102]

[Table 14]

From Table 8, it can be seen that the sample of the present invention shows a high value for both the midpoint sensitivity and the low density sensitivity, and the low density portion is hardened.

[0104]

According to the present invention, it has been found that an image having high sensitivity and high contrast in the low density portion on the reversal characteristic curve can be obtained.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03C 1/09 G03C 8/08

Claims (3)

(57) [Claims] 1. A metal complex represented by the following general formula (I):
Form particles in a dispersion medium containing at least one(However, the side
Ethylene having at least one thioether structure in the chain
Having a repeating unit derived from an unsaturated monomer
Except when particles are formed using the body as a peptizer)This
And an internal latent image type direct positive silver halide emulsion. General formula (I) [M (CN)₆]^n-  In the formula, M: Cr, Mn, Co, Ir, Ru, Rh, Re, Osn: 3 or 4 2. Tabular silver halide grains wherein the internal latent image type direct positive silver halide emulsion according to claim 1 has an average grain diameter of 0.3 μm or more and a ratio of average grain diameter / average grain thickness of 2 or more. 2. The internal latent image type direct positive silver halide emulsion according to claim 1, wherein the emulsion contains 50% or more of all silver halide grains. 3. An image receiving layer, a white reflective layer,
A light-shielding layer, a light-sensitive sheet having at least one silver halide emulsion layer combined with at least one dye image-forming substance, a transparent cover sheet having at least a neutralization layer and a neutralization timing layer on a transparent support, and 2. A color diffusion transfer photographic film unit comprising a light-shielding alkaline processing composition which is arranged between a photosensitive sheet and the transparent cover sheet, wherein at least one of the silver halide emulsion layers is formed. 3. A color diffusion transfer photographic film unit comprising an internal latent image type direct positive silver halide emulsion according to claim 2.