JP2000305234A - Internal latent image type direct positive silver halide emulsion and color diffusion transfer photosensitive material using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal latent image type direct positive silver halide emulsion having high sensitivity and giving high contrast to a low density part on a reversal characteristic curve and to provide a color diffusion transfer photosensitive material excellent in graininess using the silver halide emulsion. SOLUTION: The silver halide emulsion has a core/shell structure consisting of a chemically sensitized core and a chemically sensitized shell. In the chemical sensitization of the core and/or shell, a compound of the formula A-(W)n-R having a group which is attracted to silver halide and a reducing group or a precursor of the compound is contained in combination with a gold sensitizer and a compound having a C=X bond, a P=X bond or an R-XO2X bond (where X is S, Se or Te and R is an aliphatic hydrocarbon group, an aryl group or a heterocyclic group). In the formula, A is a group of atoms including the group which is attracted to silver halide, W is a divalent combining group, (n) is 0 or 1 and R is the reducing group.

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 photographic emulsion and a color diffusion transfer photosensitive material using the same.

[0002]

2. Description of the Related Art Photographs using silver halide have excellent sensitivity and gradation characteristics as compared with those obtained by other photographic methods, for example, electrophotography and diazo photography, and have been used widely in the past. Have been. Among them, a method of directly forming a positive image is known. For example, as disclosed in U.S. Pat. No. 3,761,276 and Japanese Patent Publication No. 60-55821, an internal latent image type direct positive silver halide photographic emulsion is used to form an internal latent image-formed halogen. When the silver halide grains are developed with a surface developer (a developer that leaves a latent image forming site inside the silver halide grains substantially undeveloped),
A positive image is obtained by giving a uniform exposure or by using a nucleating agent.

In recent years, there has been an increasing demand for silver halide photographic light-sensitive materials to have high sensitivity, excellent graininess, high gradation and high sharpness, good preservability, and rapid processing with rapid development progress. Has become. In particular, there is a strong demand for higher sensitivity while keeping fog low and having good storage stability. Attempts at reduction sensitization for high sensitivity have long been considered. To date, stannous chloride (U.S. Pat.
87850), polyamines and cyclic amine compounds (2
Nos. 518698, 2521925, and 393086
No. 7, etc.), thiourea dioxide compounds (UK Patent No. 78)
No. 9823, U.S. Pat. Nos. 2,983,609 and 2,983
No. 610, etc.), borane compounds (US Pat.
It has been disclosed that compounds such as No. 77, No. 3782959, and No. 415,093) and ascorbic acid (European Patent No. 369,491A) are useful as reduction sensitizers for silver halide emulsions. Furthermore, Collier is Photographic Science and Engineering23
Vol. 113, page 1979, compares the properties of silver nuclei made by various reduction sensitization methods. She has dimethylamine borane, stannous chloride, hydrazine, high p
The method of H ripening and low pAg ripening was adopted.

In general, reduction sensitization tends to generate remarkable fog when coexisting with gold sensitization, and the emulsion sensitized by reduction has particularly poor storage stability. Therefore, in order to improve these, not only the selection of the reduction sensitizer but also a device of the reduction sensitization method has been devised. In the above-mentioned patents, reduction sensitization was performed almost after silver halide grains were formed. However, the timing of reduction sensitization has been devised, and it has been studied to perform reduction sensitization at the time of silver halide grains formation. For example, JP-A-48-
87825, 50-3619, European Patent 3489
No. 34A, No. 369391A, No. 371338A,
No. 435355A and the like.

[0005]

However, in these methods, the above-mentioned well-known reduction sensitizers are used at the time of forming silver halide grains. Is also easy to generate. Therefore, in order to suppress fog silver nuclei and improve the storage stability of the emulsion as described in some of the above documents, it was necessary to use an oxidizing agent such as thiosulfonic acid or iodine in combination. . However, when a large amount of these compounds that oxidize silver nuclei are used, the sensitization obtained by angle reduction sensitization is greatly reduced, and when the amount is small, the effect of improving storage stability and suppressing fog are insufficient. In addition, these oxidizing agents often cause adverse effects due to by-products and residues generated by the oxidation reaction. Therefore, the development of a reduction sensitization method which does not require the use of an oxidizing agent or requires only a small amount of use, has low fog, and has good storage stability has been awaited.

JP-A-8-272024 discloses a reduction sensitization method for a silver halide photographic emulsion characterized by using a compound having an adsorbing group and a reducing group to silver halide or a precursor thereof. I have. This describes that a silver halide photographic emulsion having low fog, high sensitivity, and excellent storage stability can be obtained.However, there is no specific description about an internal latent image type direct positive silver halide emulsion. No effect is described when applied to an emulsion which directly forms a positive image. It has been conventionally known that the reduction sensitizing nucleus itself is not useful in an internal latent image type direct positive silver halide emulsion. In the internal latent image type direct positive silver halide emulsion, the gold sensitization nucleus is an effective photosensitive center especially at the time of core chemical sensitization, but the fog nucleation accompanied by a decrease in the reversal positive performance due to excessive use of the gold sensitizer. The drawback of forming is conventionally recognized. Therefore, development of a discrimination control method capable of forming a gold sensitized center with high sensitivity without forming fog nuclei as much as possible has been eagerly desired.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide an internal latent image type direct positive silver halide emulsion having a high sensitivity and a high contrast at a low density portion on a reversal characteristic curve. A color diffusion transfer photographic film unit.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide an internal latent image type direct positive silver halide emulsion of the following (1), (2), (3), (4), and (5): It has been found that this can be achieved by a color diffusion photographic light-sensitive material using photographic light-sensitive material.

(1) Chemically sensitized core and chemical sensitization
Having a core / shell structure composed of a shell
In an image-type direct positive emulsion, the core and / or shell
Silver halide represented by the following general formula (I) during chemical sensitization
A compound having an adsorbing group and a reducing group to
Gold sensitizer and C = X bond, P = X bond or R-XO
_TwoA compound having an X bond (where X is sulfur, selenium or
Tellurium, R represents an aliphatic hydrocarbon group, an aryl group or
(Representing a cyclic group).
Image-type direct positive silver halide emulsion. General formula (I) A- (W)_n—R} In the formula (I), A contains a group that can be adsorbed to silver halide.
Represents an atomic group, W represents a divalent linking group, and n represents 0 or
And R represents a reducing group. ｝

(2) A compound having a group adsorbed to silver halide and a reducing group represented by the formula (I) or a precursor thereof is contained together with a gold sensitizer at the time of core chemical sensitization. The internal latent image type direct positive silver halide emulsion as described in (1) above.

(3) The internal latent image type direct positive silver halide emulsion comprises tabular silver halide grains having an average grain diameter of 0.3 μm or more and a ratio of average grain diameter / average grain thickness of 2 or more. The internal latent image type direct positive silver halide emulsion according to the above (1) or (2), wherein the emulsion contains 50% or more of all silver halide grains.

(4) The compounds (1) to (3), wherein the compound having an adsorptive group and a reducing group to silver halide represented by the general formula (I) is a benzothiazolium.
An internal latent image type direct positive silver halide emulsion according to any one of the above.

(5) A color diffusion transfer photosensitive material comprising at least one photosensitive silver halide emulsion layer combined with a dye image-forming substance on a support, wherein the dye image-forming substance is represented by the following general formula (II): A non-diffusible compound that releases a diffusible dye or a precursor thereof in connection with silver development or a compound that changes the diffusivity of itself, and at least one of the silver halide emulsion layers is A color diffusion transfer photosensitive material comprising the internal latent image type direct positive silver halide emulsion according to any one of the above (1) to (4).

Formula (II) (DYE-Y) _m -Z In formula (II), DYE represents a dye group, a temporarily shortened dye group or a dye precursor group, and Y represents a simple bond or Z represents a property which causes a difference in diffusivity of the compound represented by (DYE-Y) _m -Z corresponding to or inversely corresponding to a photosensitive silver salt having a latent image in an image form. M represents 1 or 2, and when m is 2, two DYEs
-Y may be the same or different. ｝

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. First, general formula (I) will be described. In the general formula (I), examples of the atom group containing a group adsorbable on silver halide represented by A include mercapto compounds (for example, mercaptotetrazole group, mercaptotriazole group, mercaptoimidazole group, mercaptothiadiazole group). , Mercaptooxadiazole group, mercaptobenzthiazole group, mercaptobenzoxazole group, mercaptobenzimidazole group, mercaptotetraazaindene group, mercaptopyridyl group, mercaptoalkyl group, mercaptophenyl group, etc., thione compound (for example, thiazoline-2-) Thione group, imidazoline-2
A thione group, a benzimidazoline-2-thione group, a benzthiazoline-2-thione group, a thiourea group, a thioamide group, etc., a compound forming an imino silver (for example, a benzotriazole group, a tetrazole group, a hydroxytetraazaindene group, Benzimidazole group).
Among them, mercapto compounds and thione compounds are preferred.

In the general formula (I), a divalent linkage represented by W
The groups are carbon, hydrogen, oxygen, nitrogen and sulfur
Represents a divalent linking group composed of atoms,
Is an alkylene group having 1 to 20 carbon atoms (for example, a methylene group,
Ethylene group, trimethylene group, tetramethylene group, hex
A methylene group, etc., an arylene group having 6 to 20 carbon atoms (eg,
Phenylene group, naphthylene group, etc.), -CONR
¹-, -SO_TwoNR^Two-, -O-, -S-, -NR^Three−, −
NR^FourCO-, -NR^FiveSO_Two-, -NR⁶CONR⁷−,
—COO—, —OCO— and the like. here,
R¹, R^Two, R^Three, R^Four, R ^Five, R⁶Or R⁷Is an aliphatic radical
Or an aromatic group. Two or more of these groups are each suitable.
They may be combined as appropriate to form a divalent linking group.

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ or R ⁷
The aliphatic group represented by preferably has 1 to 30 carbon atoms, and particularly is a linear, branched or cyclic alkyl group, alkenyl group, alkynyl group, or aralkyl group having 1 to 20 carbon atoms. . Examples of the alkyl group, alkenyl group, alkynyl group, and aralkyl group include a methyl group, an ethyl group, an isopropyl group, a t-butyl group, an n-octyl group,
n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, allyl group,
2-butenyl group, 3-pentenyl group, propargyl group,
Examples include a 3-pentynyl group and a benzyl group. Also,
The aromatic group represented by R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ or R ⁷ preferably has 6 to 30 carbon atoms,
Particularly, it is a monocyclic or condensed aryl group having 6 to 20 carbon atoms, such as a phenyl group and a naphthyl group.

In the general formula (I), the reducing group represented by R may be any functional group capable of reducing silver halide, and specific examples include a formyl group, an amino group, an acetylene group and a hydrazino group. Can be Of these, a formyl group, an amino group and a hydrazino group are preferred.

The precursor of the compound having an adsorbing group and a reducing group to silver halide, when added to a silver halide emulsion, undergoes a chemical reaction such as an oxidation-reduction reaction or a hydrolysis reaction to obtain a compound of the general formula (I) Of the compound. For example, thiazoliums (including benzothiazoliums and naphthothiazoliums), thiazolines and thiazolidines, which form a mercapto group as an adsorptive group and a formyl group as a reducing group by a hydrolysis reaction (for example, compound 13) And a disulfide compound having a reduction activity in which a disulfide group is cleaved to generate a mercapto group as an adsorptive group.

Specific examples of the compound represented by formula (I) of the present invention are shown below, but the compound of the present invention is not limited thereto.

[0021]

Embedded image

[0022]

Embedded image

[0023]

Embedded image

The internal latent image type direct positive silver halide emulsion (hereinafter sometimes abbreviated as "internal latent image type silver halide emulsion") of the present invention is mainly composed of an internal latent image type silver halide emulsion upon image exposure. Specifically, a silver halide emulsion which forms a latent image on a transparent support is coated with a predetermined amount of the silver halide emulsion, and is exposed for a fixed time of 0.01 to 1 second. In the following developer A ("internal type" developer), a second sample exposed in the same manner as described above and having a maximum density obtained when developed at 20 ° C. for 5 minutes was subjected to the following developer B (“surface ("Mold" developer) at 20 ° C. for 5 minutes, defined as having a density at least 5 times greater than the maximum density obtained. 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 liter

Developer B N-methyl-p-aminophenol sulfite 2.5 g 1-ascorbic acid 10 g Potassium metanitrate 35 g Potassium bromide 1 g Add water and add 1 liter

In order to obtain a direct positive image, a uniform second exposure is applied to the front surface of the exposed layer before image development 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
No. 151) or a development treatment in the presence of a nucleating agent ("chemical fogging method", for example, Research Disclosure, Vol. 151, No. 151).
62, pages 76 to 78), but in the present invention, a method of directly obtaining a positive image by the "chemical fogging method" is preferable.

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. Alternatively, development processing is performed in the presence of a nucleating agent. Examples of nucleating agents include U.S. Pat. Nos. 2,563,785 and 2,563.
Hydrazines described in US Pat. No. 588,982; hydrazides described in US Pat. No. 3,227,552; hydrazones; British Patent 1,283,835;
-69613, 55-138742, 60-1
Nos. 1837, 62-210451, 62-291
637, U.S. Pat. Nos. 3,615,515 and 3,71
9,494, 3,734,738 and 4,09
4,683, 4,115,122, 4,30
Heterocyclic quaternary salt compounds described in US Pat. Nos. 6,016, 4,471,044 and the like, and a substituent having a nucleating function described in US Pat. No. 3,718,470 in a dye molecule. Sensitizing dyes, U.S. Pat.
No. 31,127, No. 4,245,037, No. 4,25
Nos. 5,511, 4,266,013, 4,27
No. 6,364, British Patent No. 2,012,443 and the like, and thiourea-bonded acylhydrazine compounds described in US Pat. Nos. 4,080,270 and 4,278,748.
And a thiohydrazine compound having a heterocyclic group such as a triazole or tetrazole bonded as an adsorbing group described in U.S. Pat. No. 2,011,391B or the like.

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 to 2 g per mole of silver.
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 type emulsion having the same area.

In the present invention, a core / shell type internal latent image type silver halide emulsion is used. As core / shell type internal latent image type silver halide emulsions, for example, US Pat.
Conversion-type silver halide emulsions such as described in JP-A-56,953 and JP-A-2,592,250,
Laminated silver halide emulsions having different halogen compositions of the first phase and the second phase as described in US Pat. No. 3,935,014 and the like, silver halide emulsions doped with metal ions, and the like can be given. . Other examples of core / shell silver halide emulsions include US Pat. No. 3,206,313.
No. 3,317,322 and 3,761,266
Nos. 3,761,276 and 3,850,637
Nos. 3,923,513 and 4,035,185
Nos. 4,184,878 and 4,395,478
No. 4,504,570, JP-A-57-13664.
No. 1, No. 61-3137, and JP-A No. 61-299155.
And JP-A-62-208241.

The shell of the present invention is a silver halide phase formed after chemically sensitizing silver halide grains forming a core in the step of preparing an emulsion.
The method for producing the shell is described in Examples of JP-A-63-151618, and U.S. Patent Nos. 3,206,316 and 3,31.
7,322, 3,761,276, 4,26
Nos. 9,927 and 3,367,778 can be referred to. In this case, the core / shell molar ratio (molar ratio) is preferably from 1/30 to 5/1, more preferably from 1/20 to 2/1, and still more preferably from 1/20 to 1 / l.
It is one.

The present invention is preferably applied to a tabular internal latent image type core / shell direct positive silver halide emulsion. Tabular grains are described in Photographic Science and Engineering (Gutoff, Photographic S
cience and Engineering), Vol. 14, 248-257
P. (1970); U.S. Patent No. 4,434,226;
Nos. 4,414,310, 4,433,048, 4,439,520 and British Patent 2,112,15
It can be prepared by the method described in No. 7, etc.

In some cases, a method of adding previously precipitated silver halide grains to a reaction vessel for preparing an emulsion is disclosed in US Pat. Nos. 4,334,012 and 4,301,
241 and 4,150,994 are preferred. 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 a time, a plurality of additions, or a continuous addition. It is also effective in some cases to add particles having various halogen compositions to modify the surface.

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.

In the preparation of an emulsion containing tabular grains, a silver salt solution (for example, AgN
It is preferable to increase the rate, amount and concentration of the addition of the O ₃ aqueous solution and the halide solution (for example, an aqueous KBr solution). Regarding these methods, for example, British Patent No. 1,335,925, US Pat. No. 3,672,90
No. 0, 3,650,757, 4,242,445
And JP-A-55-142329 and JP-A-55-15812.
No. 4, etc. can be referred to.

In preparing the emulsion of the present invention, for example, in forming grains,
The presence of a metal ion salt during the desalting step, during chemical sensitization, and before coating is preferred depending on the purpose. By the presence of the metal ion salt in this manner, it is possible to increase the amount of overexposure without causing reinversion and to lower the minimum density. When doping particles,
At the time of grain formation, when used as a modification of the grain surface or as a chemical sensitizer, it is preferably added after grain formation and before the end of chemical sensitization. In the case of doping the entire grain, a method of doping only the core portion, only the shell portion, or only the epitaxial portion, or only the base particle of the grain can be selected. May be). Mg, Ca, Sr,
Ba, Al, Sc, Y, La, Cr, Mn, Fe, C
o, Ni, Cu, Zn, Ga, Ru, Rh, Pd, R
e, Os, Ir, Pt, Au, Cd, Hg, Tl, I
n, Sn, Pb, Bi, etc. can be used.
e, Co, Ru, Ir, Pt, Au and Pb are preferred,
Particularly, Fe, Ru, Ir, and Pb are preferable.

These metals include ammonium salts, acetates, nitrates, sulfates, phosphates, hydroxides or hexacoordination complexes,
Any salt can be added as long as it can be dissolved at the time of particle formation, such as a four-coordinate complex salt. For example, CdBr ₂ , CdC
l ₂ , Cd (NO ₃ ) ₂ , Pb (NO ₃ ) ₂ , Pb (CH ₃ CO
O) ₂ , K ₃ [Fe (CN) ₆ ], (NH ₄ ) ₄ [Fe (C
N) ₆ ], K ₃ IrCl ₆ , NH ₄ RhCl ₆ , K ₄ Ru (C
N) _{6 and the} like. The ligand of the coordination compound can be selected from halide, H ₂ O, cyano, cyanate, nitrosyl, thionitrosyl, oxo, and carbonyl. One of these metal compounds may be used, or two or more of them may be used in combination.

The metal compound is preferably added after being dissolved in water or a suitable solvent such as methanol or acetone. To stabilize the solution, an aqueous solution of hydrogen halide (eg, H
Cl, HBr, etc.) or alkali halides (eg, K
Cl, NaCl, KBr, NaBr, etc.) can be used. If necessary, an acid, an alkali, or the like may be added. The metal compound can be added to the reaction vessel before the formation of the particles or during the formation of the particles. It can also be added to a water-soluble silver salt (eg, AgNo ₃ ) or an aqueous alkali halide solution (eg, NaCl, KBr, KI) and added continuously during silver halide grain formation. Further, a solution independent of the water-soluble silver salt and alkali halide may be prepared and added continuously at an appropriate time during grain formation. It is also preferable to combine various addition methods.

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, and Research Disclosure, 134
Vol., June 1975, 13452.

The silver halide grains of the present invention may be normal grains such as cubes, octahedrons, and tetradecahedrons. In the case of tabular grains, triangular, hexagonal and circular shapes are selected. be able to. A regular hexagon having almost equal lengths of six sides as described in U.S. Pat. No. 4,996,137 is a preferred form.

The tabular emulsion preferably used in the present invention is
An emulsion in which silver halide grains having an aspect ratio (equivalent circle diameter of silver halide grains / grain thickness) of 2 or more and 100 or less exist in an amount of 50% or more (area) of all silver halide grains in the emulsion. An emulsion in which silver halide grains having an aspect ratio of 5 or more, more preferably 8 or more, are present in an amount of 50% (area) or more of all silver halide grains in the emulsion, preferably 70% or more, and particularly preferably. Is 85%
These are the existing emulsions. Here, the equivalent circle diameter in the tabular silver halide grains is the equivalent circle diameter of two opposing parallel or nearly parallel main planes (the diameter of a circle having the same projected area as the main plane), and the grain thickness. Represents the distance between the main planes. Further, when the aspect ratio exceeds 100, there is a problem that the emulsion is deformed or destroyed in a process until the emulsion is completed as a coated product,
Not preferred.

The equivalent circle diameter of the tabular grains is at least 0.3 μm, preferably 0.3 to 10 μm, more preferably 0.1 μm.
5 to 5.0 μm, more preferably 0.5 to 3.0 μm
It is. The particle thickness is less than 1.5 μm, preferably 0.0
5 to 1.0 μm. Furthermore, the variation coefficient of the particle thickness is 3
Emulsions having a thickness uniformity of 0% or less are also preferred. 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. 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.

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. Further, the grain size distribution of the silver halide grains is arbitrary, but is preferably monodispersed. Here, monodisperse means that 95% of the total weight or the total number of silver halide grains contained therein is within ± 60% of the number average grain size,
It is preferably defined as a dispersion that falls within 40% of the size. Here, the number average grain size is the number average diameter of the projected area diameter of the silver halide grains. The structure and production method of monodisperse tabular grains are described in, for example, JP-A-63-151618, and these monodisperse emulsions may be used as a mixture.

As the silver halide composition of these grains, any of silver iodobromide, silver iodochlorobromide and silver chloroiodide may be used, but silver iodobromide is preferred.

The silver halide grains of the present invention have different phases on the inside and on the surface, but the silver halide composition inside the grains may be uniform or may be composed of a heterogeneous silver halide composition. May be. The surface phase may be a discontinuous layer or may have a continuous layer structure. Further, particles having dislocation lines may be used.

It is important to control the halogen composition in the vicinity of the surface of the grain. When changing the halogen composition in the vicinity of the surface, either a structure that covers the entire grain or a structure in which only a part of the grain is attached can be selected. . For example, this is a case where the halogen composition is changed only on one side of the tetradecahedral grain composed of the (100) plane and the (111) plane, or the halogen composition on one of the main plane or the side face of the tabular grain is changed.

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 in the same emulsion layer. It is possible to

In the silver halide emulsion of the present invention, it is preferred that after the shell is coated on the chemically sensitized core grain, the grain surface is further subjected to chemical sensitization. This is because, in general, the chemical sensitization on the surface of the grains shows good reversal performance with a high maximum density. When chemical sensitization is performed on the grain surface, a polymer as described in JP-A-57-13641 may be allowed to coexist.

In the present invention, the chemical sensitization of at least one of the above-mentioned core and shell chemical sensitizations is preferably carried out by using the above-mentioned compound of the general formula (I) and a gold sensitizer in combination. pAg 5-10, pH 4-8 and temperature 30-80
Performed in ° C. A typical example of the gold sensitizer is chloroauric acid or an alkali salt thereof. Another chemical sensitizer may be used in combination with the compound of the formula (I) and the gold sensitizer. Preferably, chemical sensitization of the core is carried out by using a compound of the general formula (I) and a gold sensitizer in combination. Further, it is not necessary that both the core and the shell are chemically sensitized by using the compound of the general formula (I) and the gold sensitizer together, in which case the compound of the general formula (I) or the gold sensitizer is used. Chemical sensitization by a single sensitizer alone or another chemical sensitizer is applied.

In other words, as chemical sensitizers, there are other examples of the theory of the photographic process by James, 4th edition, published by Macmillan, 1977 (T.
H. James, The Theory of the Photographic Process,
4th ed., Macmillan, 1977), active gelatin can be used as described on pages 67-76, and Research Disclosure, Vol. 120, April 1974.
Mon, 12008; Research Disclosure, 34
Vol., June 1975, 13452, U.S. Pat.
2,361, 3,297,446, 3,77
No. 2,031, No. 3,857,711, No. 3,90
Nos. 1,714, 4,266,018 and 3,90
No. 4,415, and British Patent No. 1,315,755, sulfur, selenium, tellurium, platinum, palladium, iridium, rhodium, osmium, rhenium, or a combination of these sensitizers. be able to.

The gold sensitizer is preferably used in a proportion of 5 × 10 ⁻⁵ to 1 × 10 ⁻⁷ mol, more preferably 1 × 10 ⁻⁵ to 1 ×, with ^respect to 1 mol of silver halide in the core grains. Used at 10 ^-6 mol. The compound of the general formula (I) to be used in combination therewith is preferably used in a 10-fold to 1 / 10-fold (molar ratio) with respect to the gold sensitizer, and most preferably about an equimolar amount. Also, when the shell grains are chemically sensitized, the above amount is preferably used based on the silver halide of the shell grains.

The chemical sensitization of the photographic emulsion of the present invention
Although it can be performed with a metal material such as e, Cr, Mn, Ni, Mo, and Ti, it is more preferably performed in a nonmetal material having a metal surface coated with a fluororesin. Examples of the fluororesin material include Teflon coating materials PFA, TFE, FEP, etc. developed by DuPont.

Further, chemical sensitization can be carried out in the presence of a chemical sensitization aid. 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 used. Examples of chemical sensitization aids are described in U.S. Pat. Nos. 2,131,038 and 3,411,
Nos. 914 and 3,554,757, JP-A-58-12
No. 6536, No. 62-253159, and "Photographic Emulsion Chemistry" by Duffin, pp. 138-143 (1966).

Further, Japanese Patent Application Laid-Open Nos. 61-3134 and 61-3
The sensitization method using an oxidizing agent described in JP-A-136 can be further 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, and silver selenide, or may form 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 adduct (for example,
NaBO 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 salts (eg 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 ₂ O, permanganate (eg, KMnO ₄ ), chromate (eg, K ₂ Cr ₂ O ₇ )
And the like, a halogen element such as iodine and bromine, a perhalate (eg, potassium periodate), and a salt of a high-valent metal (eg, potassium hexacyanoferric acid). Examples of the organic oxidizing agent include quinones such as p-quinone, organic peroxides such as peracetic acid and perbenzoic acid,
Compounds that release active halogen (for example, N-bromosuccinimide, chloramine T, chloramine B) and the like are mentioned as examples.

Preferred oxidizing agents of the present invention are organic oxidizing agents such as ozone, hydrogen peroxide and its adducts, halogen elements and quinones. It is a preferred embodiment to use the above-described reduction sensitization and an oxidizing agent for silver in combination. The method can be selected from a method of performing reduction sensitization after using an oxidizing agent, a method reverse thereto, or a method of coexisting both methods. These methods can be selectively used in both the grain formation step and the chemical sensitization step.

In the present invention, the compound having a C ＝ X bond used during chemical sensitization is preferably a compound represented by the following formula (A).

[0057]

Embedded image

In the general formula (A), X represents a sulfur atom, a selenium atom or a tellurium atom, and R ¹¹ , R ¹² ,
R ¹³ and R ¹⁴ are each a hydrogen atom, an aliphatic hydrocarbon group,
Represents an aryl group, a heterocyclic group, an acyl group, an amino group, an alkoxy group, a hydroxy group, or a carbamoyl group, which may be linked to form a ring.

In the general formula (A), R ¹¹ , R ¹² , R ¹³ and R
^The aliphatic hydrocarbon group represented by ¹⁴ has 1 to 1 carbon atoms
30 substituted or unsubstituted linear or branched alkyl groups (e.g., methyl, ethyl, isopropyl, n-
Propyl group, n-butyl group, t-butyl group, 2-pentyl group, n-hexyl group, n-octyl group, t-octyl group, 2-ethylhexyl group, 1,5 dimethylhexyl group, n-decyl group, n-dodecyl, n-tetradecyl, n-hexadecyl, hydroxyethyl, hydroxypropyl, 2,3-dihydroxypropyl, carboxymethyl, carboxyethyl, sodium sulfoethyl, diethylaminoethyl, diethylaminopropyl Group, butoxypropyl group, ethoxyethoxyethyl group, n-hexyloxypropyl group, etc., substituted or unsubstituted cyclic alkyl group having 3 to 18 carbon atoms (for example, cyclopropyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, Adamantyl group, cyclododecyl group, etc.), carbon number To 16 of the alkenyl group (for example,
An allyl group, a 2-butenyl group, a 3-pentenyl group or the like, an alkynyl group having 2 to 10 carbon atoms (for example, a propargyl group,
Examples thereof include a 3-pentynyl group), an aralkyl group having 6 to 16 carbon atoms (e.g., a benzyl group), and the like. As the aryl group, a substituted or unsubstituted phenyl group and a naphthyl group having 6 to 20 carbon atoms (e.g., Unsubstituted phenyl group, unsubstituted naphthyl group, 3,5-dimethylphenyl, 4-butoxyphenyl group, 4-dimethylaminophenyl group, etc.), and examples of the heterocyclic group include a pyridyl group, a furyl group, and an imidazolyl group. , Piperidyl group, morpholyl group and the like, and the acyl group includes, for example, acetyl group, formyl group, benzoyl group, pivaloyl group, caproyl group,
Examples of the amino group include an unsubstituted amino group, a methylamino group, a hydroxyethylamino group, an n-octylamino group, a dibenzylamino group, a dimethylamino group, a diethylamino group, and the like. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-butyloxy group, a cyclohexyloxy group,
Examples include an n-octyloxy group and an n-decyloxy group. Examples of the carbamoyl group include an unsubstituted carbamoyl group, an N, N-diethylcarbamoyl group, and an N-phenylcarbamoyl group. However, they may be connected to each other to form a ring.

Further, in the above general formula (A), R ¹¹ ,
R ¹² , R ¹³ and R ¹⁴ may have a substituent as much as possible. Examples of the substituent include a halogen atom (eg, a fluorine atom, a chlorine atom, a bromine atom, etc.) and an aliphatic hydrocarbon group (eg, Methyl, ethyl, isopropyl, n-propyl, t-butyl, n-octyl, cyclopentyl, cyclohexyl, etc., alkenyl group (eg, allyl, 2-butenyl, 3-pentenyl, etc.), alkynyl group (eg, propargyl, 3-pentynyl, etc.) ), Aralkyl groups (eg, benzyl, phenethyl, etc.), aryl groups (eg, phenyl, naphthyl, 4-methylphenyl, etc.), heterocyclic groups (eg, pyridyl, furyl, imidazolyl, piperidinyl, morpholyl, etc.), alkoxy groups (eg, methoxy,
Ethoxy, butoxy, 2-ethylhexyloxy, ethoxyethoxy, methoxyethoxy, etc., an aryloxy group (eg, phenoxy, 2-naphthyloxy, etc.), an amino group (eg, unsubstituted amino, dimethylamino, diethylamino, dipropylamino, dibutylamino) , Ethylamino, dibenzylamino, anilino, etc.), acylamino group (eg, acetylamino, benzoylamino, etc.), ureido group (eg, unsubstituted ureide, N-methylureide, N-phenylureide, etc.), thioureido group (eg, unsubstituted) Thioureido, N-methylthioureide, N-
Phenylthioureido, etc.), urethane group (eg, methoxycarbonylamino, phenoxycarbonylamino, etc.), sulfonylamino group (eg, methylsulfonylamino, phenylsulfonylamino, etc.), sulfamoyl group (eg, unsubstituted sulfamoyl group, N, N-dimethylsulfur) Famoyl, N-phenylsulfamoyl, etc.), carbamoyl group (for example, unsubstituted carbamoyl,
N, N-diethylcarbamoyl, N-phenylcarbamoyl, etc.), a sulfonyl group (eg, mesyl, tosyl, etc.),
Sulfinyl group (eg, methylsulfinyl, phenylsulfinyl, etc.), alkyloxycarbonyl group (eg, methoxycarbonyl, ethoxycarbonyl, etc.), aryloxycarbonyl group (eg, phenoxycarbonyl, etc.), acyl group (eg, acetyl, benzoyl, formyl, pivaloyl, etc.) An acyloxy group (eg, acetoxy, benzoyloxy, etc.), a phosphoric amide group (eg, N, N-diethylphosphoramide, etc.), an alkylthio group (eg, methylthio, ethylthio, etc.), an arylthio group (eg, phenylthio, etc.), a cyano group A sulfo group, a thiosulfonic acid group, a sulfinic acid group, a carboxy group, a hydroxy group, a mercapto group, a phosphono group, a nitro group, a sulfino group, an ammonio group, a phosphonio group (for example, trimethylammonio and the like), Dorajino group, Chiazorino group, a silyloxy group (t-butyldimethylsilyloxy, t-
Butyldiphenylsilyloxy) and the like. When there are two or more substituents, they may be the same or different.

In the preferred compound represented by the general formula (A), R ¹¹ , R ¹² , R ¹³ and R ¹⁴ each represent a hydrogen atom, a substituted or unsubstituted straight-chain or branched-chain having 1 to 6 carbon atoms. An alkyl group, a substituted or unsubstituted cyclic alkyl group having 3 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted phenyl group having 6 to 10 carbon atoms, a heterocyclic group, and an acyl group. And more preferably a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group having 6 to 10 carbon atoms, and an acyl group.

As a more preferred compound represented by the general formula (A), Z is a selenium atom or a tellurium atom, and at least one water-soluble group is contained in R ¹¹ , R ¹² , R ¹³ and R ^14. It is preferably contained, and preferred water-soluble groups are a sulfo group, a carboxy group, a hydroxy group, an ammonium group, and an amino group, and more preferred are a sulfo group, a carboxy group, and a hydroxy group.

Specific examples of the compound represented by formula (A) are shown below, but the present invention is not limited thereto.

[0064]

Embedded image

[0065]

Embedded image

[0066]

Embedded image

[0067]

Embedded image

The compound represented by the general formula (A) of the present invention can be prepared by a known method, for example, Chemical Reviews (Che).
m. Rev .. 55, 181-228 (1955), Journal of Organic Chemistry (J.O.
rg. Chem. ) 24, 470-473 (195
9), Journal of Heterocyclic Chemistry (J. Heterocycl. Chem.) 4,
605-609 (1967), "Drug Journal", 82, 36-4.
5 (1962), JP-B-39-26203, JP-A-6-26203
It can be synthesized with reference to 3-229449 and OLS-2,043,944.

The following are specific synthesis examples. Synthesis of Compound (A-10) Methyl isothiocyanate (239.4 ml, 3.5 m
ol) in acetonitrile (1.2 L) was added dropwise while keeping a solution of ethanolamine (211 ml, 3.5 mol) in methanol (1.2 L) at 50 ° C. or lower.
After stirring the reaction mixture at 40 ° C. for 1 hour, the solution was distilled off under reduced pressure using an evaporator. By recrystallizing the obtained crystalline residue with acetonitrile, compound (A-10) (4
13 g, 3.1 mol, yield 88%).

As the compound having a P = X group used in chemical sensitization, a phosphorus compound represented by the following general formula (B) is preferable.

[0071]

Embedded image

In the general formula (B), R ²¹ , R ²² ,
The aliphatic group represented by R ²³ , R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ , R ²⁸ , R ²⁹ , R ³⁰ and R ³² preferably has 1 to 30 carbon atoms, and particularly has 1 to 30 carbon atoms. 1-20 linear, branched or cyclic alkyl, alkenyl, alkynyl and aralkyl groups. Examples of the alkyl group, alkenyl group, alkynyl group, and aralkyl group include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, t-butyl group, n-
Examples include octyl, n-decyl, n-hexadecyl, cyclopentyl, cyclohexyl, allyl, 2-butenyl, 3-pentenyl, propargyl, 3-pentynyl, benzyl, phenethyl and the like.

In the general formula (B), R ²¹ , R ²² ,
The aromatic group represented by R ²³ , R ²⁵ , R ²⁶ , R ²⁷ , R ³¹ and R ³² is preferably an aromatic group having 6 to 30 carbon atoms, particularly a monocyclic or condensed ring having 6 to 20 carbon atoms. A ring aromatic group such as a phenyl group and a naphthyl group.

In the general formula (B), R ²¹ , R ²² ,
^{R 23, R 24, R 25} , R 26, R 27, heterocyclic group nitrogen atom represented by R ³¹ and R ^32, saturated 3-10 membered ring containing at least one oxygen atom and a sulfur atom Alternatively, it is an unsaturated heterocyclic group. These may be a single ring or may form a condensed ring with another aromatic or heterocyclic ring. The heterocyclic group is preferably a 5- to 6-membered aromatic heterocyclic group, for example, a pyridyl group, a furyl group, a thienyl group, a thiazolyl group, an imidazolyl group, a benzimidazolyl group and the like.

The aliphatic group, aromatic group and heterocyclic group may be substituted. Examples of the substituent include the following. Representative substituents include, for example, alkyl groups, aralkyl groups, alkenyl groups, alkynyl groups, aryl groups, alkoxy groups, aryloxy groups, amino groups, acylamino groups, ureido groups, urethane groups, sulfonylamino groups, sulfamoyl groups, Carbamoyl group, sulfonyl group, sulfinyl group, alkyloxycarbonyl group, aryloxycarbonyl group, acyl group,
Acyloxy group, phosphoric acid amide group, diacylamino group,
Examples include an imide group, an alkylthio group, an arylthio group, a halogen atom, a cyano group, a sulfo group, a carboxyl group, a hydroxy group, a phosphono group, a nitro group, a phosphine telluroyl group, and a heterocyclic group. These groups may be further substituted. When there are two or more substituents, they may be the same or different. R ²¹ , R ²² and R ²³ may combine with each other to form a ring together with a phosphorus atom,
(N, P- alkyldiaryl ZAZIE phosphonic fetish gin ring containing) and R ^25, R ²⁶ may form a nitrogen-containing heterocyclic ring bonded to.

Hereinafter, specific examples of the compound represented by formula (B) of the present invention will be shown, but the present invention is not limited thereto.

[0077]

Embedded image

[0078]

Embedded image

The compound represented by formula (B) of the present invention can be synthesized with reference to known literature. For example, Organic
Phosphorus Compounds, Volume 4, 1-73, J. Chem. So
c. (B), 1416 (1968), J. Org.Chem., 32, 1717 (196
7), ibid., 32, 2999 (1967), Tetrahedron, 20, 449 (1
964), J. Am. Chem. Soc., Vol. 91, 2915 (1969).

On the other hand, R-XO ₂ used for chemical sensitization
As the compound having an X bond, the following general formula (C):
Compounds represented by (D) and (E) are preferred.

[0081]

Embedded image

When R ⁴⁰ , R ⁴¹ and R ⁴² are aliphatic groups, they are saturated or unsaturated linear, branched or cyclic aliphatic hydrocarbon groups, preferably alkyl groups having 1 to 22 carbon atoms. A alkenyl group having 2 to 22 carbon atoms and an alkynyl group, which may have a substituent. Examples of the alkyl group include methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, 2-ethylhexyl, decyl, dodecyl, hexadecyl, octadecyl,
Examples include cyclohexyl, isopropyl, and t-butyl. Examples of the alkenyl group include allyl and butenyl. Examples of the alkynyl group include propargyl and butynyl.

The aromatic groups represented by R ⁴⁰ , R ⁴¹ and R ⁴² include:
It contains a monocyclic or condensed ring aromatic group and preferably has 6 to 20 carbon atoms, and examples thereof include phenyl and naphthyl. These may be substituted. R ⁴⁰ , R
^Examples of the heterocyclic group of ⁴¹ and R ⁴² include nitrogen, oxygen, sulfur,
3 to 15 having at least one element selected from selenium and tellurium and having at least one carbon atom
A 3-membered ring, preferably a 3- to 6-membered ring,
For example, pyrrolidine, piperidine, pyridine, tetrahydrofuran, thiophene, oxazole, thiazole, imidazole, benzothiazole, benzoxazole,
Examples include benzimidazole, selenazole, benzoselenazole, tellurazole, triazole, benzotriazole, tetrazole, oxadiazole, and thiadiazole ring.

Examples of the substituent for R ⁴⁰ , R ⁴¹ and R ⁴² include an alkyl group (for example, methyl, ethyl, hexyl),
Alkoxy group (eg, methoxy, ethoxy, octyl), aryl group (eg, phenyl, naphthyl, tolyl), hydroxy group, halogen atom (eg, fluorine, chlorine, bromine, iodine), aryloxy group (eg, phenoxy), alkylthio group (Eg, methylthio, butylthio), arylthio group (eg, phenylthio), acyl group (eg, acetyl, propionyl, butyryl, valeryl), sulfonyl group (eg, methylsulfonyl,
Phenylsulfonyl), acylamino group (eg, acetylamino, benzoylamino), sulfonylamino group (eg, methanesulfonylamino, benzenesulfonylamino), acyloxy group (eg, acetoxy, benzoxy), carboxyl group, cyano group, sulfo group, amino group, -SO ₂ SM group, (M is a monovalent cation) -SO ₂
R ¹ group is mentioned.

The divalent linking group represented by L includes
An atom or an atomic group containing at least one selected from C, N, S and O. Specifically, an alkylene group, an alkenylene group, an alkynylene group, an arylene group, -O-,
-S -, - NH -, - CO -, - SO 2 - is made of a single or combination of such. L is preferably a divalent aliphatic group or a divalent aromatic group. Examples of the divalent aliphatic group for L include the following.

[0086]

Embedded image

Examples of the divalent aromatic group represented by L include a phenylene group and a naphthylene group. These substituents may be further substituted with the substituents described above.

[0088] M is preferably a metal ion or an organic cation. Examples of the metal ion include a lithium ion, a sodium ion, and a potassium ion. Examples of the organic cation include an ammonium ion (ammonium, tetramethylammonium, tetrabutylammonium, etc.), a phosphonium ion (tetraphenylphosphonium), and a guanidyl group. When the general formulas (C), (D) and (E) are polymers, examples of the repeating unit include the following.

[0089]

Embedded image

These polymers may be homopolymers or copolymers with other copolymerized monomers. Compounds of general formulas (C), (D) and (E) are disclosed in
4-1019; British Patent 972, 211; Journal of O
rganic Chemistry (Journal of Organic
Chemistry) 53, 396 (1988) and Chem.
ical Abstracts (Chemical Abstracts) 59 volumes,
It can be easily synthesized by the method described or cited in 9776e.

The compound represented by formula (C), (D) or (E) is used in an amount of 10 ^-7 to 10 ^-1 per mol of silver halide.
It is preferred to add them in molar. Further, the addition amount is preferably from 10 ^-7 to 10 ^-3 mol, particularly preferably from 10 ^-6 to 10 ^-4 mol.

In order to add the compounds represented by the general formulas (C), (D) and (E) during the production process, a method usually used for adding an additive to a photographic emulsion can be applied. For example, a water-soluble compound is an aqueous solution having an appropriate concentration, and a compound insoluble or hardly soluble in water is an appropriate organic solvent miscible with water, for example, alcohols, glycols, ketones, esters, amides and the like. Of these, the compound can be dissolved in a solvent that does not adversely affect photographic characteristics and added as a solution.

The compounds represented by the general formulas (C), (D) and (E) need to be present at the time of chemical sensitization of the core particles.
It may be added at any stage during the production. . Compounds (C), (D) and (E) are added in advance to an aqueous solution of a water-soluble silver salt or a water-soluble alkali halide,
Core particles may be formed using these aqueous solutions.
In addition, even if the solutions of the compounds (C), (D) and (E) are added in several portions at the same time as the formation of the core particles or the chemical sensitization of the core particles, the addition is continued for a long time. Is also a preferred method.

Of the above, the compounds represented by formula (C) are most preferred. Specific examples of the compounds represented by formulas (C), (D) and (E) are shown below, but the effects of the present invention are not limited to these compounds.

[0095]

Embedded image

[0096]

Embedded image

[0097]

Embedded image

[0098]

Embedded image

[0099]

Embedded image

[0100]

Embedded image

In the present invention, it is preferable to use the compound represented by formula (C), (D) or (E) at the time of chemical sensitization of the core particles. At the time of chemical sensitization of the core particles, it is more preferable to carry out the chemical sensitization under the condition that the thiosulfate ion usually used for sulfur sensitization does not substantially exist. The condition in which thiosulfate ions are not substantially present refers to a concentration of 1 ppm or less.

It is advantageous to use gelatin as a protective colloid used in preparing the emulsion of the present invention, but other hydrophilic colloids can also be used. For example, gelatin derivatives, graft polymers of gelatin and other macromolecules, proteins such as albumin and casein; hydroxyethyl cellulose, carboxymethyl cellulose, cellulose derivatives such as cellulose sulfates,
Sugar derivatives such as sodium alginate and starch derivatives; polyvinyl alcohol, polyvinyl alcohol partial acetal,
Various kinds of synthetic hydrophilic high molecular substances such as a single or copolymer such as poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, and polyvinylpyrazole can be used.

Examples of gelatin include lime-treated gelatin, acid-treated gelatin and Bull. Soc. Sci. Photo. Japan, No. 1
6, p. 30 (1966), enzyme-treated gelatin may be used, and a hydrolyzate or enzymatic degradation product 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. The coagulation sedimentation method can be selected from a method using a sulfate, a method using an organic solvent, a method using a polymer for washing, a method using a gelatin derivative, and the like.

In the present invention, spectral sensitization can be performed using a sensitizing dye. The sensitizing dyes used include cyanine dyes, merocyanine dyes, composite cyanine dyes, composite merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, and hemioxonol dyes. Specifically, U.S. Patent Nos. 4,617,257, JP-A-59-180550, and JP-A-60-140335,
No. 61-160739, RD17029 (1978
Year) 12-13, RD17643 (1978) 23
And the like, sensitizing dyes described on pages, 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 and 4,026,707, British Patent Nos. 1,344,281 and 1,507,803, JP-B-43-4936, JP-B-53-12375, JP-A-5
Nos. 2-110618 and 52-109925.

Along with the sensitizing dye, a dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization may be contained in the emulsion (for example, US Pat. No. 3,615,613, No. 3,6
No. 15,641, No. 3,617,295, No. 3,63
No. 5,721, No. 2,933,390, No. 3,74
3,510 and JP-A-63-23145).

The sensitizing dye for spectral sensitization 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 carried out after completion of chemical sensitization and before coating, but as described in U.S. Pat. Nos. 3,628,969 and 4,225,666, a chemical sensitizer is used. Japanese Patent Application Laid-Open (JP-A) No. 58-11 / 1990 also discloses that spectral sensitization may be performed at the same time as chemical sensitization.
It can be carried out prior to chemical sensitization as described in No. 3928, or can be added before completion of precipitation of silver halide grains to start spectral sensitization. Furthermore, the addition of these compounds separately as taught in U.S. Pat. No. 4,225,666, i.e., adding some of these compounds prior to chemical sensitization,
The remainder can be added after chemical sensitization, at any time during the formation of silver halide grains, including the method disclosed in U.S. Pat. No. 4,183,756.

The addition amount is 10 mol per mol of silver halide.
It 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 from 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 described in JP-A-59-168442, or nitrogen-containing carboxylic acids and phosphoric acids, or mercapto compounds and metal salts thereof described in JP-A-59-111636, -87
No. 957, acetylene compounds and the like are used.

Further, phenethyl alcohol and JP-A-63
257747, 62-272248 and JP-A-1-80941, 1,2-benzisothiazoline
Various preservatives or fungicides such as -3-one, n-butyl, p-hydroxybenzoate, phenol, 4-chloro-3,5-dimethylphenol, 2-phenoxyethanol, 2- (4-thiazolyl) benzimidazole Is preferably added. For details, see European Patent No. 436,938A2 1
It is described on page 50, lines 25-28. These additives are described in more detail in Research Disclosure It
em17643 (1978) and Item18716 (19
November 1979) and Item 307105 (January 1989)
(Jan.), and the relevant locations are summarized in the table below.

Types of Additives RD17643 RD18716 RD307105 (December 1978) (November 1979) (November 1989) 1 Chemical sensitizer 23 page 648 right column 866 page 2 Sensitivity enhancer 648 page right column 3 Spectral sensitizer, page 23-24 page 648, right column, page 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, page 650, left column, page 872 Inhibitor, right column 8 Dye image 25 page 650 page left column 872 Stabilizer 9 Hardener 26 page 651 page left column 874-875 10 Binder page 26 Same as above 873-874 11 plasticizer, page 27 650 page right column page 876 Lubrication Agent 12 Coating aid, pages 26-27 Same as above, pages 875-876 Surfactant 13 Static page 27 Same as above, pages 876-877 Inhibitor 14 Matting agent 878-879

Next, the color diffusion transfer photosensitive material of the present invention will be described. The most typical form of the color diffusion transfer material is a color diffusion transfer film unit, and the typical form is such that an image receiving element and a photosensitive element are laminated on one transparent support, and the transferred image is formed. After completion of the above, there is no need to peel the photosensitive element from the image receiving element. More specifically, the image receiving element comprises at least one mordant layer, and in a preferred embodiment of the photosensitive element, a combination of a blue-sensitive emulsion layer, a green-sensitive emulsion layer and a red-sensitive emulsion layer,
Or a combination of a green-sensitive emulsion layer, a red-sensitive emulsion layer and an infrared-sensitive emulsion layer, or a combination of a blue-sensitive emulsion layer, a red-sensitive emulsion layer and an infrared-sensitive emulsion layer, and yellow in each of the above-mentioned emulsion layers. The dye image-forming compound, the magenta dye image-forming compound and the cyan dye image-forming compound are respectively combined (here, the “infrared-sensitive emulsion layer” is 700 nm or more,
In particular, an emulsion layer having a spectral sensitivity maximum with respect to light of 740 nm or more). A white reflective layer containing a solid pigment such as titanium oxide is provided between the mordant layer and the photosensitive layer or the dye image forming compound-containing layer so that the transferred image can be viewed through the transparent support.

A light-shielding layer may be further provided between the white reflective layer and the photosensitive layer so that the developing process can be completed in a light place. If desired, a release layer may be provided at an appropriate position so that all or a part of the photosensitive element can be peeled from the image receiving element. Such an embodiment is disclosed in, for example,
67840 and Canadian Patent 674,082.

Further, as another embodiment of a laminate type, which is peeled off, at least (a) a layer having a neutralizing function, (b) a dye image-receiving layer, a white support described in JP-A-63-226649. (C) a release layer, (d) a light-sensitive element sequentially having at least one silver halide emulsion layer combined with a dye image-forming compound, an alkali treatment composition containing a light-shielding agent, and a transparent cover sheet, the emulsion layer comprising: A color diffusion transfer photographic film unit having a layer having a light-shielding function on the side opposite to the side on which the processing composition is spread.

In another mode in which peeling is unnecessary, the above-described photosensitive element is coated on one transparent support, a white reflective layer is coated thereon, and an image receiving layer is further laminated thereon. .
An image receiving element, a white reflective layer, a release layer, and a photosensitive element are laminated on the same support, and an embodiment in which the photosensitive element is intentionally peeled from the image receiving element is described in US Pat. No. 3,730,71.
No. 8 is described.

On the other hand, there are roughly two typical forms in which a photosensitive element and an image receiving element are separately coated on two supports, respectively, one of which is of a peeling type, and the other is of a peeling-free type. is there. More specifically, in a preferred embodiment of the peelable film unit, at least one image receiving layer is coated on one support, and the photosensitive element is coated on a support having a light shielding layer. Before the end of the exposure, the coated surface of the photosensitive layer and the coated surface of the mordant layer do not face each other, but after the end of the exposure (for example, during the developing process), the coated surface of the photosensitive layer is inverted in the image forming apparatus and is in contact with the coated surface of the image receiving layer. It is devised as follows. After the transfer image is completed in the mordant layer, the photosensitive element is immediately separated from the image receiving element.

In a preferred embodiment of the peeling-free type film unit, at least one mordant layer is coated on a transparent support, and a photosensitive element is coated on a support having a transparent or light-shielding layer. The surface on which the photosensitive layer is applied and the surface on which the mordant layer is applied face each other.

A pressure-rupturable container (processing element) further containing an alkaline processing liquid may be combined with the above-described embodiment. In particular, in a peeling-free film unit in which an image receiving element and a photosensitive element are laminated on one support, the processing element is preferably arranged between the photosensitive element and a cover sheet overlaid thereon. In the case where the photosensitive element and the image receiving element are separately coated on the two supports, it is preferable that the processing element is arranged between the photosensitive element and the image receiving element at the latest at the time of development processing. Processing elements include:
Depending on the type of film unit, light shielding agent (carbon
It is preferable to include one or both of black or a dye whose color changes depending on pH) and a white pigment (such as titanium oxide). Further, in the film unit of the color diffusion transfer system, it is preferable that a neutralization timing mechanism composed of a combination of a neutralization layer and a neutralization timing layer is incorporated in the cover sheet, the image receiving element, or the photosensitive element.

The dye image-forming substance used in the present invention is a non-diffusible compound which releases a diffusible dye (which may be a dye precursor) or changes its diffusivity in connection with silver development. "Theory of the Photographic Process" 4th
It is stated in the edition. All of these compounds can be represented by the general formula (II).

According to the function of Z in the general formula (II), 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 Z include those which oxidize as a result of development and are cleaved to release a diffusible dye. Specific examples of Z include U.S. Pat. Nos. 3,928,312, 3,993,638, 4,076,529, 4,152,153, 4,055,428, and 4,053. No. 3,312, No. 4,198,235, No. 4,179,291, No. 4,149,892, No. 3,844,785, No. 3,443,943, No. 3,751,406 Nos. 3,443,939, 3,443,940, 3,628,952, 3,980,479, 4,183,753, 4,142,891; 4,278,750, 4,139,379, 4,218,368, 3,421,964, 4,199,355, 4,199,354, and 4 , 135,929, 4,336,322, 4,139,389, HirakiAkira 53-50736 issue, same 51-104343 JP, the same 5
4-130122, 53-110827, 56
-12642, 56-16131, 57-40
No. 43, No. 57-650, No. 57-20735, No. 53-69033, No. 54-130927, No. 56
No. 164342, No. 57-119345 and the like.

Among the Z of 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). it can. Representative groups of Z are exemplified below, but are not limited thereto.

[0125]

Embedded image

For positive-type compounds, see Angev. Chem. Int. Ed. Engl., 22, 191.
(1982). Specific examples include compounds (dye developing agents) which are initially diffusible under alkaline conditions, but are oxidized by development to become non-diffusible. Z useful in this type of compound is disclosed in US Pat.
No. 3606 is representative.

Another type is a type in which a diffusible dye is released by, for example, self-ring closure under alkaline conditions, but the dye is substantially not released when oxidized during development. Specific examples of Z having such a function are described in U.S. Pat. No. 3,980,479 and JP-A-53-69.
No. 033, No. 54-130927, U.S. Pat.
Nos. 1,964 and 4,199,355.

Another type does not release the dye itself, but releases the dye when reduced.
Compounds of this type are used in combination with an electron donor,
The diffusible dye can be released 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 4,142,891.
No. 4,278,750, 4,139,379
No. 4,218,368, JP-A-53-11082.
7, U.S. Pat. Nos. 4,278,750 and 4,356,
Nos. 249 and 4,358,535, JP-A-53-11
0827, 54-130927, 56-164
No. 342, published technical report 87-6199, European Patent Publication 2
20746A2. Specific examples of Z will be described below, but the present invention is not limited thereto.

[0129]

Embedded image

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. 63,393 and 4,278,750;
No. 138736. Specific examples of other types of dye image-forming substances include the following.

[0131]

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 the formula DYE 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. , 383, 4,195,992, 4,148,641, 4,148,643 and 4,336,322: JP-A-51-114930,
No. 56-71072: Research Disclosure 1763
No. 0 (1978) and No. 16475 (1977).

Examples of magenta dyes: US Pat. No. 3,453,
No. 107, No. 3,544,545, No. 3,932,3
No. 80, No. 3,931,144, No. 3,932,30
No. 8, 3,954, 476, 4, 233, 237
Nos. 4,255,509 and 4,250,246
Nos. 4,142,891, 4,207,104
No. 4,287,292: JP-A-52-10672.
No. 7, No. 53-23628, No. 55-36804,
No. 56-73057, No. 56-71060, No. 55
-134.

Examples of cyan dyes: US Pat. No. 3,482,9
No. 72, No. 3,929,760, No. 4,013,63
No. 5, 4,268,625, 4,171,220
Nos. 4,242,435 and 4,142,891
Nos. 4,195,994 and 4,147,544
No. 4,148,642; British Patent 1,551,1
No. 38; JP-A-54-99431, JP-A-52-8827.
No. 53-47823, No. 53-143323,
Nos. 54-99431 and 56-71061; European Patents (EP) 53,037 and 53,040;
Research Disclosure 17,630 (1978) and 16,475 (1977).

These compounds are disclosed in JP-A-62-2152.
No. 72, pages 144 to 146. These dispersions are described in JP-A-62-215.
No. 272, pp. 137-144.

[0137]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto. Example 1 First, a method for preparing a silver halide emulsion will be described. The following ten kinds of silver halide emulsion grains [Emulsion-A to Emulsion-G, Emulsion-T, Emulsion-U, and Emulsion-X were prepared by the following emulsion grain preparation methods.

Preparation of Emulsion-A (octahedral internal latent image type direct positive emulsion): 0.05 M potassium bromide, 1 g of 3,6-dithia-1,8-octanediol, 0.034 mg of lead acetate
And deionized gelatin 60 having a Ca content of 100 ppm or less
g in 1000 ml of an aqueous gelatin solution containing
While maintaining the temperature at 5 ° C., a 0.4 M aqueous solution of silver nitrate and a 0.4 M aqueous solution of potassium bromide were controlled by the double jet method while controlling the addition rate of the aqueous solution of potassium bromide so that the pBr was 1.60. Was added over 40 minutes. When the addition was completed, octahedral silver bromide crystals (hereinafter referred to as core particles) having an average particle size (equivalent sphere size) of about 0.7 μm and a uniform particle size were produced.

Next, core chemical sensitization was performed in the following container and formulation. 1. Tank: Fluororesin material F developed by DuPont for metal surface
Hemisphere bottom shape with Teflon coating with thickness 120μm by EP. 2. Stirring impeller: Seamless, integral type, propeller type with Teflon coated metal surface.

3. Prescription: 10 mg of sodium benzenethiosulfate, 90 μg of potassium tetrachloroaurate and 1.2 g of potassium bromide were added to the above octahedral direct positive emulsion in 1000 ml of water.
Was added thereto, and heated at 75 ° C. for 80 minutes for chemical sensitization. After adding 0.15M potassium bromide to the emulsion solution thus chemically sensitized, a 0.9M silver nitrate aqueous solution and 0.9M Potassium bromide aqueous solution of pBr by the control double jet method
670 ml of an aqueous solution of silver nitrate was added over 70 minutes while controlling the addition rate of the aqueous solution of potassium bromide so that the value became 1.30. This emulsion was washed with water by a conventional flocculation method, and the above-mentioned gelatin, 2-phenoxyethanol and methyl p-hydroxybenzoate were added thereto, and the average particle diameter (equivalent sphere diameter) was adjusted to about 1.4 μm. Octahedral silver bromide crystals (hereinafter referred to as internal latent image type core / shell grains) were obtained.

Next, 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate were added to the internal latent image type core / shell emulsion.
Was added to 1000 ml of water and 3 ml of an aqueous solution was added.
After addition of mg of poly (N-vinylpyrrolidone) and aging at 60 ° C., 0.005 M potassium bromide was added to prepare an octahedral internal latent image type direct positive emulsion.

Preparation of Emulsions-B to E-G (octahedral internal latent image type direct positive emulsion): In the preparation method of Emulsion-A, the addition time of an aqueous solution of silver nitrate and an aqueous solution of potassium bromide were changed.
The amount of the added chemicals was further changed to obtain an octahedral internal latent image type direct positive silver halide emulsion having the average particle size (equivalent sphere diameter) shown in Table 1 having a uniform particle size.

[0143]

[Table 1]

Preparation of Emulsion-T (hexagonal tabular internal latent image type direct positive emulsion): Potassium bromide 0.05M, 1.2 liter of gelatin aqueous solution containing 0.7% by weight of gelatin having an average molecular weight of 100,000 or less. And 1.4 containing the aforementioned gelatin.
33 ml of each of the M aqueous silver nitrate solution and the 2 M aqueous potassium bromide solution were simultaneously mixed for 1 minute by the double jet method with vigorous stirring. During this time, the gelatin aqueous solution was kept at 30 ° C. Further, 300 ml of a gelatin solution containing 10% by weight of deionized gelatin having a Ca content of 100 ppm or less was added, and the temperature was raised to 75 ° C. Next, 40 ml of 0.9 M silver nitrate aqueous solution
Was added over 3 minutes, and a 25% by weight aqueous ammonia solution was added, followed by aging at 75 ° C. After the ripening, ammonia was neutralized, and then 5 mg of lead acetate (added in an aqueous solution) was added, and a 1M silver nitrate aqueous solution and a 1M potassium bromide aqueous solution were accelerated while maintaining the pBr at 2.5 (flow rate at the end). The flow rate was 6 times the flow rate at the start) and the mixture was added by the double jet method (the amount of the used silver nitrate aqueous solution was 500 ml). The particles thus formed (hereinafter referred to as core particles) are washed with water by a conventional flocculation method, and gelatin, 2-phenoxyethanol and methyl P-hydroxybenzoate are added to obtain 750 g of hexagonal flat core particles. Obtained. The obtained hexagonal tabular core grains had an average projected area equivalent circle diameter of 0.9 μm and an average thickness of 0.20 μm, and 95% of the total projected area was occupied by the hexagonal tabular grains.

Next, core chemical sensitization was performed in the following container and formulation. 1. Tank: Fluororesin material F developed by DuPont for metal surface
Hemisphere bottom shape with Teflon coating with thickness 120μm by EP. 2. Stirring impeller: Seamless, integral type, propeller type with Teflon coated metal surface.

[0146] 3. Formula: Hexagonal flat core emulsion 200
After adding 1300 ml of water, 0.11 M of potassium bromide and 40 g of deionized gelatin to the resulting mixture, the mixture was heated to 75 ° C.
2.4 g of an aqueous solution of 0.3 g of dithia-1,8-octanediol, 10 mg of sodium benzenethiosulfate and 90 mg of potassium tetrachloroaurate and 1.2 g of potassium bromide in 15 ml of water, and 15 mg of lead acetate (to the aqueous solution) ), And heated at 75 ° C. for 180 minutes to perform a chemical sensitization treatment. A 2M silver nitrate aqueous solution and a 2.5M aqueous potassium bromide solution were added to the chemically sensitized core particles in the same manner as in the preparation of the core particles, and an aqueous potassium bromide solution was added so that the pBr was 2.2. While adjusting the speed, the accelerated flow rate (the flow rate at the end is 3 times the flow rate at the start).
And the double-jet method (the amount of the used silver nitrate aqueous solution was 810 ml). After adding 0.3 M potassium bromide, 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 2.0 μm.
m, average thickness is 0.38 μm, average volume size is 1.
At 3 (μm) ³ , 88% of the total projected area was occupied by hexagonal tabular grains. Next, 15 ml of an aqueous solution of 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate dissolved in 1000 ml of water were added to the hexagonal tabular internal latent image type core / shell emulsion, and 20 mg of poly (N-vinylpyrrolidone) was further added. By heating at 100 ° C. for 100 minutes, the grain surface was chemically sensitized to prepare a hexagonal tabular internal latent image type direct positive emulsion.

Preparation of Emulsion-X (AgI fine grain emulsion): 80 g of an aqueous silver nitrate solution containing 40 g of silver nitrate and 39 g of 40 g of silver nitrate were added to a solution containing 0.5 g of potassium iodide and 26 g of gelatin in water and stirred at 35 ° C. 80 cc of an aqueous solution containing potassium iodide was added over 5 minutes. At this time, the addition flow rates of the silver nitrate aqueous solution and the potassium iodide aqueous solution were each 8 ml / min at the start of the addition, and the addition flow rates were linearly accelerated so that the addition of 80 ml was completed in 5 minutes. After the formation of the particles was completed, the soluble salts were removed by settling at 35 ° C. Next, the temperature was raised to 40 ° C., and 10.5 g of gelatin and 2.56 g of phenoxyethanol were added.
H was adjusted to 6.8. The obtained emulsion had a finished amount of 730.
g of monodispersed AgI fine particles having an average diameter of 0.015 μm.

Preparation of Emulsion-U (hexagonal tabular internal latent image type direct positive emulsion): When forming the outer shell of Emulsion-T, 0.15 mol% of iodine was uniformly contained, and the amount of outer shell was further reduced. By increasing, the average projected area circle equivalent diameter becomes 2.5
μm, the average grain thickness was 0.45 μm, the average volume size was 1.7 (μm) ³ , and 88% of the total projected area was occupied by hexagonal tabular grains. Next, shell chemical sensitization similar to that of Emulsion-T was performed to prepare a hexagonal tabular internal latent image type direct positive emulsion.

As described below, the reducing substances shown in Tables 2 to 4 were added simultaneously with the addition of potassium tetrachloroaurate for the core chemical sensitization, and Comparative Emulsions A-1 to A-7 and A-12 to A-A were added. -13,
T-1 to T-7, T-12 to T-13, U-1 to U-
7, U-12 to U-13, and emulsions A-8 to A of the present invention
-11, T-8 to T-11, and U-8 to U-11 were respectively prepared.

[0150]

[Table 2]

[0151]

[Table 3]

[0152]

[Table 4]

Using Emulsion-A to Emulsion-G, the following Table 5 was used.
Comparative Photosensitive Element (Sample 101) having the structure shown in Table 8 was prepared. The sensitizing dye was added at the end of the shell chemical sensitization at the dye type, dispersion form, addition temperature, and amount shown in Table 9 below.

[0154]

[Table 5]

[0155]

[Table 6]

[0156]

[Table 7]

[0157]

[Table 8]

[0158]

[Table 9]

[0159]

Embedded image

[0160]

Embedded image

[0161]

Embedded image

[0162]

Embedded image

[0163]

Embedded image

[0164]

Embedded image

[0165]

Embedded image

[0166]

Embedded image

[0167]

Embedded image

[0168]

Embedded image

[0169]

Embedded image

[0170]

Embedded image

[0171]

Embedded image

Next, the emulsions of the eighth, fourteenth and twentieth layers are shown in Tables 10 to 11 as emulsions A-2 to A-1.
3, T-1 to T-13, and only the twentieth layer is U-1
To U-13, samples 102 to 113, 2
01 to 213 and 301 to 313 were prepared respectively.

[0173]

[Table 10]

[0174]

[Table 11]

The cover sheet was prepared as follows. The following layers were coated on a polyethylene terephthalate support containing a light-piping preventing dye and subbed with gelatin. (A) 10.4 g of an acrylic acid / n-butyl acrylate copolymer having an average molecular weight of 50,000 (80/20 (mol%))
/ M ² and 1,4-bis (2,3-epoxypropoxy) - butane 0.1 g / m ² comprises a neutralizing layer. (B) 4.3 g of cellulose acetate having a degree of acetylation of 55%
/ M ² and a layer containing 0.2 g / m ² of a methyl half ester of a methyl vinyl ether / maleic anhydride copolymer (50/50 (mol%)).

(C) n-butyl methacrylate having an average molecular weight of 25,000 / 2-hydroxyethyl methacrylate /
Ethyl methacrylate / 2-hydroxyethyl methacrylate / acrylic acid copolymer having an acrylic acid copolymer (66.1 / 28.4 / 5.5 (% by weight)) of 0.3 g / m ² and an average molecular weight of 40,000 ( 66.1 / 18.4 / 5.5
(Weight%)) of 0.8 g / m ² . KAYASE made by Nippon Kayaku Co., Ltd.
A combination of T GREEN AG and the following compounds in a ratio of 3: 1 was used.

[0177]

Embedded image

The alkaline treatment composition was prepared by the following method. 0.8 g of a treatment liquid having the following composition was filled in a container which can be broken by pressure. 695 g of water 1-p-tolyl-4-hydroxymethyl-4-methyl 7.00 g -3-pyrazolidin-1-one 1-phenyl-4-hydroxymethyl-4-methyl 9.85 g -3-pyrazolidin-1-one Sulfinic acid polymer 2.10 g 5-methylbenzotriazole 2.50 g Zinc nitrate hexahydrate 0.60 g Potassium sulfite 1.90 g Aluminum nitrate nonahydrate 0.60 g Carboxymethylcellulose Na salt 56.0 g Potassium hydroxide 55.0 g Carbon black 160 g Anionic surfactant 8.60 g Anionic surfactant 0.03 g Alkyl-modified PVA (manufactured by Kuraray Co., Ltd.) 0.06 g Cationic polymer 1.05 g

[0179]

Embedded image

The photosensitive elements 101 to 113 and 201 to 2
After exposing Nos. 13 and 301 to 313 from the emulsion layer side through a gray continuous wedge, they were superimposed on the cover sheet, and a pressure roller was used between the two materials so that the above-mentioned processing solution had a thickness of 62 μm. Expanded. The exposure was performed for 1/100 second by adjusting the exposure illuminance so that the exposure amount was constant. The treatment was performed at 25 ° C., and the transfer density was measured with a color densitometer after 10 minutes.

Tables 12 to 14 show the results. The maximum density, minimum density, midpoint sensitivity, and foot sensitivity in the table were determined as follows. That is, the logarithm of the exposure amount is displayed on the horizontal axis, and each color density is displayed on the vertical axis, and the reversal characteristic curve is drawn. Concentration. The midpoint sensitivity was defined as the sensitivity giving an intermediate density between the maximum density and the minimum density, and the foot sensitivity was defined as the sensitivity giving a density of 0.3. The sensitivity is the reciprocal of the exposure amount, and
The values are shown as relative values when Y, M, and C of 1 are each set to 100.

[0182]

[Table 12]

[0183]

[Table 13]

[0184]

[Table 14]

Samples 108 to 111 and 208 to 2 of the present invention
11 and 308 to 311 show that both the mid-point sensitivity and the foot sensitivity were higher than those of the comparative samples 101, 201 and 301. The samples 108, 208, and 308 of the present invention have higher midpoint sensitivity and foot sensitivity than the corresponding comparative samples 106, 206, and 306, respectively. Therefore, the reduction sensitizer of the present invention is It can be seen that the effect can be obtained only when used in combination. In addition, the samples 110, 111, and 21 of the present invention
The reduction sensitizers of the present invention are identified because 0, 211, 310, and 311 have higher midpoint sensitivity and foot sensitivity than the corresponding comparative samples 112, 113, 212, 213, 312, and 313, respectively. It can be seen that the effect can be obtained only when used in combination with a sulfur (chalcogen) sensitizer species.

[0186]

According to the present invention, an internal latent image type direct positive silver halide emulsion having a high sensitivity and a low density portion on a reversal characteristic curve is hardly obtained, and is used as a color diffusion transfer photosensitive material. And a reversal color image excellent in graininess can be obtained.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor: Masayoshi Yoshikawa 210 Nakanakanuma, Minamiashigara, Kanagawa Prefecture Fuji Photo Film Co., Ltd. F-term (reference) 2H023 BA04 BA05 CA02 CA04 DA01 DA02 DA03 DA04

Claims (5)

[Claims] 1. An internal latent image type direct positive emulsion having a core / shell structure comprising a chemically sensitized core and a chemically sensitized shell, wherein said core and / or shell is chemically sensitized by the following general formula (1): A compound having an adsorbing group and a reducing group to silver halide represented by I) or a precursor thereof is prepared by adding a gold sensitizer and a C = X bond, a P = X bond, or R-XO ₂ X
An internal latent image type direct positive silver halide emulsion characterized by containing together with a compound having a bond (wherein X represents sulfur, selenium or tellurium, and R represents an aliphatic hydrocarbon group, an aryl group or a heterocyclic group). . Formula (I) A- (W) _n -R In formula (I), A represents an atom group including a group that can be adsorbed to silver halide, W represents a divalent linking group, and n represents 0 Or 1 and R represents a reducing group. ｝ 2. A compound having an adsorbing group and a reducing group to silver halide represented by the general formula (I) or a precursor thereof is contained together with a gold sensitizer during core chemical sensitization. The internal latent image type direct positive silver halide emulsion according to claim 1. 3. An internal latent image type direct positive silver halide emulsion comprising all tabular silver halide grains having an average grain diameter of 0.3 μm or more and a ratio of average grain diameter / average grain thickness of 2 or more. 3. An internal latent image type direct positive silver halide emulsion according to claim 1, wherein the emulsion contains 50% or more of silver halide grains. 4. The compound according to claim 1, wherein the compound having an adsorptive group and a reducing group for silver halide represented by the general formula (I) is a benzothiazolium. An internal latent image type direct positive silver halide emulsion as described above. 5. A color diffusion transfer photosensitive material comprising at least one photosensitive silver halide emulsion layer combined with a dye image-forming substance on a support, wherein the dye image-forming substance is represented by the following general formula (II): A non-diffusible compound that releases a diffusible dye or a precursor thereof in connection with silver development or a compound that changes the diffusivity of itself, and at least one of the silver halide emulsion layers is Claim 1
5. A color diffusion transfer photosensitive material comprising the internal latent image type direct positive silver halide emulsion according to any one of the above items 4. In the general formula (II) (DYE-Y) m -Z { formula (II), DYE represents a dye group temporarily short-waved dye group or dye precursor group, Y a single bond or a linking group And Z is a group having a property which causes a difference in diffusivity of the compound represented by (DYE-Y) _m -Z corresponding to or inversely corresponding to a photosensitive silver salt having an image-like latent image. And m represents 1 or 2, and when m is 2, two DYEs
-Y may be the same or different. ｝