JPS62291635A - Silver halide photographic sensitive material having high sensitivity and less fogging - Google Patents

Abstract

PURPOSE:To prevent the decrease of a sensitization effect by varying the Miller index ratio of internal particles subjected to reduction sensitization and the Miller index ratio of the silver halide particles coated with the internal particles. CONSTITUTION:The particles which are different in the Miller index ratio of the internal particles subjected to the reduction sensitization and the Miller index ratio of the silver halide particles obtd. by coating the same with the internal particles are incorporated into the titled material. The particles having the different Miller index ratios refer to, for example, the silver halide particles which are of the fourteen-faced body intermediate of the regular octahedron and regular hexahedron and have the different area ratio of the (111) face and (100) face, and to, for example, the particles which are different in the area ratio in the comparison between the particles having only the (111) face and the particles having only the (100) face. The above-mentioned Miller index ratios can be changed as desired by controlling the pH and pAg in a reactor when a control double jet method is used in the growing stage of the silver halide particles.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a silver halide photographic material with high sensitivity and low fog.

[Conventional technology]

There is a constant demand for higher sensitivity in silver halide photographic emulsions, and the benefits to users from higher sensitivity are immeasurable, such as lower costs and improved image quality.

Conventionally, it is well known that high sensitivity can be obtained by reduction sensitization, and in particular, by applying further sensitization means, such as gold-sulfur sensitization, the sensitivity can be dramatically increased. is known to be obtained. However, when reduction sensitization and gold-sulfur sensitization are used together, there is a problem in that fog increases so much that it is not practical. This means that
It is disclosed in Japanese Patent Application Laid-Open No. 48-87825. In order to reduce fog, reduction sensitization and gold-sulfur sensitization must be performed at the same time.
It is necessary to separate within the particle. For example, if reduction sensitization is performed inside the silver halide grains and gold-sulfur sensitization is performed on the grain surfaces, the fog reduction effect is remarkable. However, when reduction sensitizing nuclei are embedded inside the particles in this way, the sensitizing effect is reduced. It is disclosed in JP-A-57-82831 that reduction sensitization effect is reduced when reduction sensitization is performed during grain growth.

In addition, reduction sensitization generally deteriorates thermal stability, and reduction sensitized emulsions can be improved by applying heat.
It is known that sensitivity decreases and fog increases significantly. This phenomenon is particularly noticeable in silver halide photographic materials that have been subjected to reduction sensitization, which has high sensitivity. On the other hand, an example in which a silver halide photographic emulsion containing reduction-sensitized silver halide grains contains a compound represented by the following general formula (1) is disclosed in JP-A-59-35737. .

However, this has the problem that the addition of the compound represented by general formula (1) causes significant desensitization.

General formula (I) yo n 3 (X-) In one set, Zl
represents the atomic group required to complete the thiazole ring or selenazole ring. R3 represents an alkyl group or an alkenyl group, and R4 represents hydrogen, an alkyl group, or a mercapto group. Further, R3 and R4 may be combined to form a ring.

X- represents an acid anion. m represents 0 or 1,
m is 0 when an inner salt is formed.

[Purpose of the invention]

An object of the present invention is to solve the problems of the above-mentioned prior art, to solve the difficulties in using other sensitization means in combination with reduction sensitization, to suppress the reduction in aggravating effects, and to further increase fogging. The object of the present invention is to provide a silver halide photographic material that does not cause

[Structure and operation of the invention]

An object of the present invention is to provide a silver halide photographic emulsion containing grains in which the surface index ratio of internal grains subjected to reduction sensitization is different from the surface index ratio of silver halide grains obtained by coating the internal grains. This can be achieved using a silver halide photographic material that has the following properties. According to the present invention, it is possible to solve the problems that arise when other sensitizing means are used in conjunction with reduction sensitization, suppress the reduction in the sensitizing effect, and prevent an increase in fog.

In a preferred embodiment of the present invention, in the silver halide photographic light-sensitive material, the silver halide photographic emulsion is selected from the group of compounds represented by the general formulas (1) and (■) (details will be described later). By containing at least one compound, it is possible to obtain a silver halide photographic material that has excellent thermal stability, high sensitivity, and little fog.

The present invention will be explained in more detail below.

The average grain size of the silver halide grains used in the present invention is preferably 0.2 μm to 3 μm, more preferably 0.4 μm to 2 μm. The composition of the silver halide grains preferably contains silver iodide such as silver iodobromide and silver chloroiodobromide. In this case, the silver iodide mole % is preferably 0.1 mole % to 10 mole %. The internal grains used in the present invention may be silver bromide, silver iodobromide, silver chlorobromide, or silver chloroiodobromide, and the silver halide coated after reduction sensitization of the internal grains is as follows: Examples include silver bromide, silver iodobromide, silver chloroiodobromide, and the like.

The silver halide emulsion used in the present invention is preferably a monodisperse emulsion. The term "monodisperse emulsion" as used herein refers to one in which -<0.20, where the average grain size of silver halide grains is 75 and the standard deviation of the grain size is r.

The distribution of silver iodide in the coated silver halide grains is arbitrary, but the silver iodide mole % is preferably 10 mole % to 40 mole %, and is preferably localized inside the grains.

The localized area of silver iodide is preferably a coated area, but may also be inside the internal grains subjected to reduction sensitization, and the silver halide grain surface has pure silver bromide or silver iodide mol% of 2 mol% or less. It is preferable.

The plane index ratio in the present invention refers to the area ratio of the (111) plane and the (100) plane of the plane index on the surface of a silver halide grain. The plane index is the Miller index defined in solid-state physics, and in the case of silver halide grains with a face-centered cubic lattice, (1
11) Those with only faces have a regular octahedral external shape, and (1
00) Those with only faces have a regular hexahedral external shape.

In the present invention, silver halide grains having the above-mentioned so-called normal crystal, that is, a regular shape, are preferred, but if the corners of the grain are rounded by solvents etc., or if the grains are significantly rounded, the spherical shape may be formed. It also includes those that present. This method is difficult to apply to so-called twin crystals that are plate-shaped, rod-shaped, or pyramid-shaped. The above surface index and surface index ratio are based on the Bulletin of the Society of Scientific Photography of Japan (Bull, Soc, Sci.
, Photo.

Japan) No., p. 13.5 (1963).

In the present invention, having a different plane index ratio means, for example, that the silver halide grain is a tetradecahedron between a regular octahedron and a regular hexahedron, and the area ratio of the (111) plane and the (100) plane is different. It also refers to a material having a different area ratio compared to, for example, a material having only a (111) surface or a material having only a (100) surface.

These surface index ratios are determined by the p
By controlling H and pAg, it can be changed freely. The silver halide grains subjected to reduction sensitization are preferably regular hexahedrons or those close to regular hexahedrons, and the silver halide grains after coating are preferably regular octahedrons or dodecahedrons close to regular octahedrons. , the effect of the present invention is great. Further, it is preferable that the internal particles subjected to reduction sensitization have more (100) planes than the plane index of the particles after coating. For example, when coating a reduction-sensitized internal particle with many (100) planes, first coat it in a hexahedral atmosphere, then coat it in an octahedral region.
11) It is preferable to increase the number of surfaces.

In the present invention, growth of internal particles for reduction sensitization,
The three steps of reduction sensitization and coating may be performed consecutively or may be performed separately. The thickness of the silver halide coating is preferably 0.02 μm or more and 2 μm or less. Further, silver halide grains can also be doped with heavy metal ions such as iridium, thallium, lead, platinum, and cadmium.

As the reducing agent in the present invention, thiourea dioxide and stannous chloride are preferable, and thiourea dioxide is silver halide 1
About 0.01 mg to about 2 mg per mole, about 0 for stannous chloride
．． It is generally appropriate to use between 0.01 mg and about 3 mg. Furthermore, the reducing agent used includes hydrazines, polyamines, sulfites, and other reducing substances. Moreover, pA, g is 1-10. pH is 5-10.30°-80
Reduction sensitization can also be performed by aging in a bath at ℃.

In the present invention, chemical sensitization can be carried out after carrying out reduction aggravation inside the grains, coating them with silver halide, and then undergoing a desalting step to remove unnecessary salts. This J) sensitization is preferably sulfur sensitization or selenium sensitization combined with gold sensitization. For sulfur sensitization, hypo, thiourea, etc. can be used.
For selenium sensitization, selenthiourea or the like can be used.

For gold sensitization, chloroauric acid, chloroauric acid thiocyanate, etc. can be used.

In a preferred embodiment of the present invention, the compounds added to the silver halide photographic emulsion are of the following general formula (I) and (
II).

General Formula (1) General Formula (II) In the formula, Zl and Z2 each represent an atomic group required to complete a thiazole ring or a selenazole ring.

R3 and R5 represent an alkyl group or an alkenyl group,
Those having substituents are also included. R4 represents a hydrogen atom, an alkyl group, or an alkylthio group, including those having a substituent. Furthermore, R3 and R4 may be combined to form a ring. L represents a sulfur atom or a divalent hydrocarbon group.

X- represents an acid anion. m represents 0 or 1, and n represents 0.1 or 2. When an inner salt is formed, m is O or 1.

Preferred specific examples of the above general formula (I) that can be used in the present invention are listed below.

zHs + 1- nCs old blind Tm4 1 Br-CH2CH=C
H2 + 1- HI 1I- H3 C)+3 CIhCHtCHzSO*- CHzCH=CHt cutcn CHt CHzcH= C8z Next, preferred specific examples of general formula (II) that can be used in the present invention are given.

II-2 + 1 2
l-CH3CI! The silver halide photographic light-sensitive material according to the present invention can be applied to various fields, but it is preferably used as a direct X-ray film, particularly a regular film, and cannot be used as a reversal film.

In the present invention, reduction sensitization is carried out as described above, and other sensitization means are also used as desired. For such chemical sensitization, for example, H. Die Gr.
undlagen der Photograp-hi
schen Prozesse mit Silver
halogeniden.

Akademische Verlagsgesell
Schafft, 1968), pages 675-734, can be used.

As sulfur sensitizers for such sensitization, thiosulfates, thioureas, thiazoles, rhodanines, and other compounds can be used as described above. Patent 1, 574.

No. 944, No. 2,410,689, No. 2,278,947
No. 2,728.668, No. 3.656,955, 4
, No. 032,928, No. 4,067.740. As the reduction sensitizer, stannous salts such as the stannous chloride mentioned above, thiourea dioxide, amines, hydrazine derivatives, formamidine sulfinic acid, silane compounds, etc. can be used. Patent 2,
No. 487.850, No. 2,419.974, No. 2,518
．． No. 698, No. 2,983.609, No. 2,983,61
No. 0, No. 2,694,637, No. 3,930,867,
No. 4,054,458. For noble metal sensitization, in addition to kumquat salts, complex salts of metals in group I of the periodic table, such as platinum, iridium, and palladium, can be used. Specific examples thereof include U.S. Pat.
．． No. 060, British Patent No. 618.061, etc.

In the present invention, in addition to reduction sensitization, various chemical sensitization methods can be used in combination.

The amount of coated silver is arbitrary, but preferably 1 glrd or more, 15 g/ry? or less, more preferably 2 g/
rd or more and 10 g/rrr or less.

Additionally, photosensitive layers containing the particles may be present on both sides of the support.

Gelatin is advantageously used as the binder or protective colloid in the photographic emulsion of the present invention, but other hydrophilic colloids can also be used.

For example, gelatin derivatives, graft polymers of gelatin and other polymers, proteins such as albumin and casein; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, and cellulose sulfates; sugar derivatives such as sodium alginate and starch derivatives; polyvinyl alcohol , polyvinyl alcohol partial acetal, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole, etc., single or copolymers thereof. Can be done.

Examples of gelatin include lime-processed gelatin, acid-processed gelatin, and Bulletin of Society of Scientific Photography (Bull, S.
oc, Sci, Phot, Japan,)No,
16.30 pages.

(1966) may be used, and gelatin hydrolysates and enzymatically decomposed products may also be used. As gelatin derivatives, various compounds such as acid halides, acid anhydrides, isocyanates, bromoacetic acids, alkanesultones, vinyl sulfonamides, maleimide compounds, polyalkylene oxides, and epoxy compounds can be added to gelatin. The product obtained by the reaction is used.

The photographic emulsion used in the present invention can contain various compounds for the purpose of preventing fogging or stabilizing photographic performance during the manufacturing process, storage, or photographic processing of the light-sensitive material. That is, azoles such as benzothiazolium salts, nitroindazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzthiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, aminotriazoles. , benzotriazoles, nitrobenzotriazoles, mercaptotetrazoles (especially 1-phenyl-5-
mercaptopyrimidines; mercaptotriazines; thioketo compounds such as oxazolinthione; azaindenes, such as triazaindenes, tetraazaindenes (especially 4-hydroxy substituted (1,3,3a, 7) Many compounds known as antifoggants or stabilizers can be added, such as tetraazaiendenes), pentaazaindenes, etc.; benzenethiosulfonic acid, benzenesulfinic acid, benzenesulfonic acid amide, etc.

The photographic emulsion layer or other hydrophilic colloid layer of a light-sensitive material using the photographic emulsion according to the present invention may contain a coating aid, an antistatic agent,
Improved slipperiness, emulsification and dispersion, prevention of adhesion and improvement of photographic properties (
For example, various surfactants may be included for various purposes such as development acceleration, contrast enhancement, and sensitization.

For example, saponins (steroids), alkylene oxide derivatives (e.g. polyethylene glycol, polyethylene glycol/polypropylene glycol condensates, polyethylene glycol alkyl ethers or polyethylene glycol alkyl aryl ethers, polyethylene glycol esters, polyethylene glycol alkyl ethers, polyalkylene glycols alkylamines or amides, polyethylene oxide adducts of silicone), glycidol derivatives (e.g. alkenylsuccinic polyglycerides, alkylphenol polyglycerides), fatty acid esters of polyhydric alcohols,
Nonionic surfactants such as alkyl esters of sugar; alkyl carboxylates, alkyl sulfonates, alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl sulfates, alkyl phosphates, N-acyl- Carboxy groups such as N-alkyl taurines, sulfosuccinates, sulfoalkyl polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl phosphates, etc.
Anionic surfactants containing acidic groups such as sulfo groups, phospho groups, sulfate ester groups, and phosphate ester groups; amphoteric surfactants such as amino acids, aminoalkyl sulfonic acids, aminoalkyl sulfates or phosphoric esters, alkyl betaines, and amine oxides. Surfactant; alkylamine salts, aliphatic or aromatic quaternary ammonium salts, pyridinium,
Cationic surfactants such as heterocyclic quaternary ammonium salts such as imidazolium, and phosphonium or sulfonium salts containing aliphatic or heterocycles can be used.

The photographic emulsions used in this invention may be spectrally sensitized with methine dyes and others. These sensitizing dyes may be used alone or in combination, and combinations of sensitizing dyes are often used particularly for the purpose of supersensitization.

Along with the sensitizing dye, it is a dye that itself does not have a spectral sensitizing effect or a substance that does not substantially absorb visible light,
A substance exhibiting supersensitization may also be included in the emulsion.

Useful enhancing dyes, supersensitizing dye combinations, and supersensitizing substances are available from Research Disclosure.
176 volume 176
43 (published December 1978), page 23, item 3.

The photographic material of the present invention may contain an inorganic or organic hardener in the photographic emulsion layer or other hydrophilic colloid layer.

Examples include chromium salts (chromium alum, chromium acetate, etc.), aldehydes (formaldehyde, glyoxal, geltaraldehyde, etc.), N-methylol compounds (dimethylol urea, methylol dimethylhydantoin, etc.), dioxane derivatives (2,3-dihydroxydioxane, etc.) ),
Active vinyl compounds (1,3,5-triacryloyl-hexahydro-5-)riazine, 1,3-vinylsulfonyl-2-propatol, etc.), active halogen compounds (2,
4-dichloro-6-hydroxy-5-)riazine, etc.),
Mucohalogen acids (mucochloric acid, mucophenoxychloric acid, etc.), etc. can be used alone or in combination.

The photographic material of the present invention may contain a dispersion of a water-insoluble or sparingly soluble synthetic polymer in the photographic emulsion layer or other hydrophilic colloid layer for the purpose of improving dimensional stability.

For example, alkyl (meth)acrylate, alkoxyalkyl (meth)acrylate, glycidyl (meth)acrylate, (meth)acrylamide, vinyl ester (e.g. vinyl acetate), acrylonitrile, olefin, styrene, etc. alone or in combination, or these and acrylic acid, Methacrylic acid, α, β-unsaturated dicarboxylic acid,
A polymer containing a combination of hydroxyalkyl (meth)acrylate, sulfoalkyl (meth)acrylate, styrene sulfonic acid, etc. as a monomer component can be used.

The photographic emulsion layer of the photographic light-sensitive material of the present invention contains a color-forming coupler, that is, a color is formed by oxidative camping with an aromatic primary amine developer (for example, a phenylenediamine derivative, an aminophenol derivative, etc.) in a color development process. It may also contain compounds that can. For example, magenta couplers include 5-pyrazolone couplers, pyrazolobenzimidazole couplers, cyanoacetylcoumarone couplers, open-chain acylacetonitrile couplers, and yellow couplers include acylacetamide couplers (e.g., benzoylacetanilides, pivaloylacetanilides). , etc., and cyan couplers include naphthol couplers, phenol couplers, etc. These couplers are preferably non-diffusive and have a hydrophobic group called a ballast group in the molecule. The coupler may be either 4-equivalent or 2-equivalent to silver ions.

It may also be a colored coupler that has a color correction effect or a coupler that releases a development inhibitor during development (so-called DIR coupler).

In addition to the DIR coupler, the coupling reaction product may include a colorless DIR coupling compound which is colorless and releases a development inhibitor.

When carrying out the present invention, the following various antifading agents may be used in combination, and the color image stabilizers used in the present invention may be used alone or in combination of two or more. Various anti-fading agents include hydroquinone derivatives, gallic acid derivatives, p-alkoxyphenols, p-oxyphenol derivatives and bisphenols.

The photosensitive material of the present invention may contain an ultraviolet absorber in the hydrophilic colloid layer. For example, benzotriazole compounds, 4-thiazolidone compounds, benzophenone compounds, cinnamic acid ester compounds, butadiene compounds, benzoxazole compounds, and ultraviolet-absorbing polymers substituted with an oryl group can be used. These ultraviolet absorbers may be fixed in the hydrophilic colloid layer.

The photosensitive material of the present invention may contain a water-soluble dye in the hydrophilic colloid layer as a filter dye or for various purposes such as preventing irradiation. Such dyes include oxonol dyes, hemioxonol dyes, styryl dyes, merocyanine dyes, cyanine dyes and azo dyes.

Among them, oxonol dyes, hemioxonol dyes and merocyanine dyes are useful.

The photosensitive material of the present invention uses hydroquinone derivatives, aminophenol derivatives, gallic acid derivatives,
It may also contain ascorbic acid derivatives and the like.

The invention is also applicable to multilayer, multicolor photographic materials having at least two different spectral sensitivities on the support.

Multilayer natural color photographic materials usually have a red-sensitive emulsion layer on a support,
It has at least one green-sensitive emulsion layer and at least one blue-sensitive emulsion layer. The order of these layers can be selected arbitrarily as needed. Usually, the red-sensitive emulsion layer contains a cyan-forming coupler, the green-sensitive emulsion layer contains a magenta-forming coupler, and the blue-sensitive emulsion layer contains a yellow-forming coupler, but different combinations may be used depending on the case.

In the photographic light-sensitive material of the present invention, the photographic emulsion layer and other hydrophilic colloid layers can be coated on the support or on other layers by various coating methods. For coating, a dip coating method, a roller coating method, a curtain coating method, an extrusion coating method, etc. can be used. U.S. Patent No. 2,681.294, No. 2
, 761,791 and 3,526,528 are advantageous methods. As the support, a cellulose ester film such as a cellulose triacetate film, a polyester film such as a polyethylene terephthalate film, or paper coated with an α-olefin polymer is preferable.

The silver halide emulsion used in the present invention can be directly or indirectly
It can be used not only for black and white photosensitive materials such as -ray photosensitive materials, lithographic photosensitive materials, and photosensitive materials for black and white photography, but also for color photosensitive materials such as color negative photosensitive materials, color reversal photosensitive materials, and color paper.

For photographic processing of the light-sensitive material of the present invention, for example, Research Disclosure (Research Disc-1) is used.
osure) No. 176, pages 28-30 (RD-176
Any of the various methods and various treatment liquids as described in 43) can be applied. This photographic processing may be either photographic processing that forms a silver image (black and white photographic processing) or photographic processing that forms a dye image (color photographic processing), depending on the purpose. The processing temperature is usually selected between 18°C and 50°C, but temperatures below 18°C or above 50°C may also be used.

Developers used in black-and-white photographic processing can contain various developing agents. As the developing agent, dihydroxybenzenes (e.g. hydroquinone), 3-pyrazolidones (e.g. 1-phenyl-3-pyrazolidone), aminophenols (e.g. N-methyl-p-aminophenol), etc. may be used alone or in combination. Can be done. Developer solutions generally contain various preservatives, alkaline agents,
Contains pH buffering agents, antifogging agents, etc., and further contains solubilizing agents, color toning agents, development accelerators, surfactants, antifoaming agents, etc.
It may also contain a water softener, a hardening agent, a viscosity imparting agent, and the like.

As the fixer, one having a commonly used composition can be used.

As a fixing agent, in addition to thiosulfate and thiocyanate,
Organic sulfur compounds known to be effective as fixing agents can be used.

The fixer may contain a water-soluble aluminum salt as a hardening agent.

Color developers generally consist of an alkaline aqueous solution containing a color developing agent. Color developing agents include various primary aromatic amine developers, such as phenylene diamines (e.g. 4-amino-N, N-diethylaniline, 3-methyl-4-amino-N, N-diethylaniline, 4-amino-N -ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-
β-methanesulfamide ethylaniline, 4-amino-
3-methyl-N-ethyl-N-β-methoxyethylaniline, etc.) can be used.

In addition, Photographic Processing Chemistry (Photo togr) by F.A. Mason
aph icProccssing Chemistry
22, Focal Press, 1966)
6-229 True, U.S. Patent No. 2,193.015, No. 2,
Those described in No. 592°364'', JP-A-48-64933, etc. may be used.

The color developer may also contain a pH buffer, a development inhibitor, an antifoggant, and the like. In addition, water softeners, preservatives, organic solvents, development accelerators, dye-forming couplers, competitive couplers, fogging agents, auxiliary developers,
It may also contain a viscosity imparting agent, a polycarboxylic acid chelating agent, an antioxidant, and the like.

After color development, the photographic emulsion layer is usually bleached. Bleaching treatment may be carried out simultaneously with fixing treatment or separately. Bleaching agents include polyvalents such as iron (■), cobalt (■), chromium (■), copper (n), etc. Metal compounds, peracids, quinones, nitroso compounds, etc. are used.

For bleaching or bleach-fixing solutions, U.S. Patent 3.042.52
In addition to bleaching accelerators described in No. 0, No. 3.24L966, Japanese Patent Publication No. 45-8506, Japanese Patent Publication No. 45-8836, etc., and thiol compounds described in Japanese Patent Publication No. 53-65732, various additives are used. You can also add

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

It goes without saying that the present invention is not limited to the examples.

Example 1 Emulsion ① was prepared in the following manner. That is, the emulsion was heated to 60°C,
pAg=8. Electron micrographs of an emulsion with an average grain size of 0.3 μm taken with a double jet method while controlling the pH to 2.0 showed that the incidence of twin grains was 1% or less. After desalting this emulsion, silver nitrate solution was added to
Reduction sensitization was performed at 0°C, pAg = 3°, pH = 6.0. The obtained emulsion was used as a seed emulsion containing silver equivalent to 50 g in terms of silver nitrate. This amount is 2 after growth.
Corresponds to %. Next, a 2.5% aqueous solution of gelatin 8.4
1 was maintained at 40''C, the above seed crystal emulsion was dissolved in this aqueous solution, and ammonia water equivalent to 0.9 N was added.Furthermore, ammoniacal silver ions were added to adjust the pAg to 7.4. Then, acetic acid was added to adjust the pH to 9.7, and 244 cc, which is equivalent to 1/15 of 3660 cc of a 3.2N ammoniacal silver ion solution, was added at a rate of 6 cc per minute.At the same time, iodination was added. Halide solution containing 0.96 N of potassium (K I ) and 2 N of potassium bromide (KBr) 24
Add 4 cc and p) with acetic acid and potassium bromide (KBr) solution.
(, pA, and g were held constant to form a localized portion of 30 mol% silver iodide (AgI). Furthermore, acetic acid and potassium bromide (
KB'r) solution to adjust the pH to 9.0゜pAg to 8.7
Then, according to the profile shown in Figure 1, equal amounts of 3.2N ammoniacal silver ion solution and 3.2N potassium bromide solution were added, pAg was kept constant, and acetic acid was added in proportion to the flow rate of addition. was added to gradually change the pH to 8. The total silver iodide (AgI) content of the obtained emulsion was 2 mol%, and the average grain size was 1.21μ@.
f/F was 0.11. Further, this emulsion was a monodisperse cubic emulsion with a surface index (1,0,0) of 100%. The emulsion obtained in the above manner was designated as emulsion (2), and ammonium thiocyanate, chloroauric acid, and hypo were added thereto for chemical ripening, and 4-hydroxy-6-methyl-L
3.3a, 7-chitrazaindene was added.

Emulsions ■ to ■ are prepared using silver iodide (
After forming a localized moiety of 30 mol % (AgI), the pH was adjusted to 9.0. pAg is 9.0.9.3°9.6, respectively, and surface index (1, 0, 0) is 70% and 30%, respectively.

0% and area index (1, 1, 1) are respectively 30%, 7
0%.

A 100% monodispersed tetradecahedral emulsion and an octahedral emulsion were obtained. The respective emulsions were designated as Emulsions ■ to ■. Each emulsion was subjected to chemical ripening in the same manner as Emulsion ■, and 4-hydroxy-6
-Methyl-1,3,3a,7-titrazaindene was added.

Emulsions ■ to ■ were prepared in the same manner as emulsion ■ except that the pAg was 9.2 when preparing the seed crystals, and the areal indices (1, 1,
A monodisperse octahedral emulsion consisting only of 1) was obtained, and this was reduction sensitized in the same manner as the emulsion and grown under the same conditions as emulsions ① to ②. Each emulsion was subjected to chemical ripening in the same manner as emulsion ①, and 4-hydroxy-6-methyl-1,3,3a
, 7-chitrazaindene was added.

Emulsion ■〜＠ is made without reduction sensitization of the seed crystal emulsion.
After growing under the same conditions as ■, N Hz (NHCS
Oz) H and ammonium thiocyanate, chloroauric acid,
and Hypo and chemical ripening to produce 4-hydroxy-6-methyl-1,3,3a.

Obtained by adding 7-chitrazaindene.

Emulsion ◎ ~ [phase] is emulsion ■ without reduction sensitization of the seed crystal emulsion.
After growing under the same conditions as ~■, chemical ripening was performed in the same way as emulsion ■, and 4-hydroxy-6-methyl-1,3,
3a, ? -obtained by adding tetrazaindene.

Conventional coating aids and hardeners were added to the emulsions (1) to (phase) prepared as described above, and the emulsions were coated on both sides of a polyethylene terephthalate support together with a protective film of gelatin. The amount of silver coated was 5.5 g per 1M, and the amount of gelatin coated was IM.
It was 3.4g per portion. Take the above coated sample from the X-ray tube.
Placed at a distance of m, 90KVP.

X-ray exposure was performed for 0.08 seconds at 50 mA. At this time, a Kyokuko LT-n regular intensifying screen was used, and an aluminum wedge was used as an intensifying screen. Development was carried out using an automatic developing machine QX-1200 manufactured by Konishiroku Photo Industry Co., Ltd., and processing was carried out at 35° C. for 90 seconds using XD-90 developer.

Furthermore, in order to determine the X-ray sensitivity, the blackening density of each sample was measured using a PDM-35 densitometer manufactured by Konishiroku Photo Industry Co., Ltd. From the obtained characteristic curve, the reciprocal of the exposed X-rays at blackening density fog +1.0 was determined, and sample No. 13 was
The sensitivity as a relative value was determined and shown in Table 1.

As is clear from Table 1, reduction sensitization is performed inside the silver halide grains, and the surface index ratio of the internal grains is different from the surface index ratio of the silver halide grains after the internal grains are coated. In some cases, no increase in Capri is observed and high sensitivity can be obtained.

Example 2 The compounds I-1, I-9, l-13, 1-16,■-2 30m
Samples 1 to 24 were prepared in the same manner as in Example 1 except that g was added.
(However, it also included those without the addition of the above compound). Next, these samples were stored at 50° C. for 3 days and subjected to a heat resistance forced deterioration test. The results are shown in Table 2. However, the sensitivity is shown as a relative value with the sample depth 13 of Example 1 being 100.

As is clear from Table 2, reduction sensitization is applied to the inside of the silver halide grains, and the surface index ratio of the internal grains is different from the surface index ratio of the silver halide grains after the internal grains are coated. Samples prepared by adding the above compounds to silver halide emulsions show little increase in fog or decrease in sensitivity, even in forced deterioration tests to evaluate photographic performance after being left alone, and can be said to be excellent in improving storage stability. .

〔Effect of the invention〕

As described above, the silver halide photographic light-sensitive material of the present invention comprises grains in which the surface index ratio of internal grains subjected to reduction sensitization is different from the surface index ratio of silver halide grains coated with the internal grains. By having a silver halide photographic emulsion containing , the reduction in the sensitizing effect is suppressed when other sensitizing means are used in combination with reduction sensitization, and the problems of the conventional technology are solved without causing an increase in capri. It is.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the state of addition of ammoniacal silver ions, etc. in Examples. Time P: 1 (minute) Figure 1

Claims (1)

[Scope of Claims] 1. In a silver halide photographic light-sensitive material having a silver halide photographic emulsion containing silver halide grains which have undergone reduction sensitization inside the grains, the surfaces of the internal grains which have undergone reduction sensitization A silver halide photographic light-sensitive material characterized in that the index ratio and the surface index ratio of the silver halide grains after coating the internal grains are different. 2. A silver halide photographic emulsion containing reduction-sensitized silver halide grains inside the grains contains at least one compound selected from the group of compounds represented by the following general formulas (I) and (II).
The silver halide photographic material according to claim 1, characterized in that it contains one compound. General formula (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ General formula (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ In the formula, Z^1 and Z^2 each complete a thiazole ring or selenazole ring The atomic group required for is shown. R^3 and R^5 each represent an optionally substituted alkyl group or alkenyl group, and R^4 represents a hydrogen atom or an optionally substituted alkyl group or alkylthio group. Furthermore, R^3 and R^4 may be combined to form a ring. L represents a sulfur atom or a divalent hydrocarbon group. X^- represents an acid anion. m represents 0 or 1, and n represents 0.1 or 2. When an inner salt is formed, m is 0 and n is 0 or 1.