JPH03137632A - Preparation of photographic silver halide emulsion - Google Patents

Abstract

PURPOSE:To enhance sensitivity of a photosensitive material even at the time of rapid development processing and to reduce fog by forming silver halide grains in the presence of a specified compound and then changing the halogen to form the silver halide high in the chloride content. CONSTITUTION:The silver halide grains to be prepared are composed of >=80 mol % silver chloride, and flat grains each having a thickness of <=0.5 mum, a diameter of >= 0.5 mum, and an aspect ratio of >= 2 occupy >= 50 % of the projection area of the total silver halide grains. The silver halide grains are formed in the presence of at least one of the compounds represented by formulae I and II, embodied by formula III, and the formed host grains is subjected to the conversion of halogen. In formulae I and II, each of A1 - A4 is an atomic group necessary to form an N-containing hetero ring; B is a linking group; each of R1 and R2 is alkyl; X is an anion; and each of (m) and (n) is 0 or 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing a photographic silver halide emulsion. In particular, the present invention relates to a tabular silver chlorobromide, silver chloroiodobromide or silver chloroiodide emulsion having a high silver chloride content and excellent rapid processability and high sensitivity.

(Prior Art) Currently, in the development processing of X-ray photosensitive materials, there is a demand for shortening the processing time and reducing the amount of waste liquid accompanying the processing. Generally, silver iodobromide emulsions are used in X-ray photosensitive materials, but to meet the above requirements, it is advantageous to use silver chlorobromide emulsions, which have a high solubility. On the other hand, in order to reduce waste liquid, it is desirable to increase image density with a small amount of silver.
It is well known among those skilled in the art that tabular grains are suitable in terms of graininess, sharpness, color sensitization efficiency, and the like.

Silver halide grains with a high silver chloride content (hereinafter referred to as "high silver chloride grains") generally tend to form cubic grains, and some measures are required to form them into tabular grains.

The method for producing silver chlorobromide tabular grains is already known, for example, as described in Japanese Patent Publication No. 8324/1983,
A method in which chloride and silver salt solutions are simultaneously introduced into a dispersion medium in the presence of ammonia by a double jet method, ■ In the presence of an aminoazaindene and a thioether condensation-containing peptizer, as described in Japanese Patent Publication No. 8326/1983. A method of reacting a silver salt aqueous solution with a chloride-containing halide salt aqueous solution, ■As described in JP-A-58-111936, the molar ratio of chloride ions to promide ions in the reaction vessel is set to 1.6:1. ~258:1 and the total concentration of halogen ions was 0.10-0.
Method of simultaneously introducing silver, chloride and bromide salts while maintaining the 90-normal range, JP-A-62-16304
6, a method of introducing silver ions into a dispersion medium containing a gelatin peptizer made from a low (both 0.5 molar concentration of chloride ions and less than 30 μmol of methionine per Ig); ■Japanese Patent Publication No. 63-281149
As described in No. 1, a method of bringing a chloride-containing halide salt into contact with an aqueous silver salt in the presence of a dispersion medium in the presence of an aminoazapyridine and a crystal habit-changing amount of its salt, JP-A No. No. 1988-218959, JP-A-63-21
3836, a method in which a halide and a silver salt solution are mixed in the presence of thiourea or a thiourea derivative, and a method using a gold compound; As described in JP-A No. 63-41845, a method of forming particles in the presence of a compound containing a sulfur atom in the heterocycle, and a method of forming particles in the presence of a compound containing a sulfur atom in the molecule, A method of forming particles in the presence of a compound is known.

Among these, the silver chloride content in the tabular grains is limited to 40 mol %, and is not suitable for producing high-silver chloride grains. In addition, it is difficult to make thin tabular grains due to the solvent action of ammonia, and the pH during grain formation is
This inevitably increases the fog of high-silver chloride emulsions that are sensitive to fog, and the grain formation conditions are severely restricted. Thiourea derivatives such as ■ The drawback is that fog is likely to occur in the peptizer.■ In the case of ■, a synthetic polymer is used, and in the case of ■, gelatin with a reduced methionine content is used as the peptizer, but in the case of ■, it is difficult to obtain a copolymer with good reproducibility. There are many drawbacks from an industrial standpoint, such as the polymerization initiator containing impurities that are harmful to photography, and the desalting step becoming complicated. In addition, (2) also has problems with increased cost and reproducibility due to the use of special gelatin.

Synthetic crystal phase control agents such as ■, ■, and ■, even after particle formation,
It remains adsorbed on silver chloride grains and is difficult to remove by a simple method, which poses a problem for subsequent chemical sensitization and spectral sensitization.

From the above, it is possible to obtain tabular high-silver chloride grains with good reproducibility by simply using a low-cost, low-molecular-weight compound that is easy to synthesize and purify in the acidic to neutral region with gelatin, which is a general-purpose bebutizer. Furthermore, the crystal phase control agent adsorbed on silver chloride grains after grain formation can be relatively easily removed by a normal desalting process using bispyridinium salts as shown in Japanese Patent Application No. 62-291487. It was a manufacturing method.

However, although high silver chloride tabular grains are extremely advantageous in reducing waste liquid, they have low sensitivity and are difficult to apply chemical sensitization or spectral sensitization.
However, the obtained sensitivity is unstable and fogging is likely to occur.

In particular, it is insufficient for applications such as X-ray photosensitive materials that require high sensitivity and require ultra-rapid processing.

As described above, it has been desired to develop a preparation method for producing emulsions with high sensitivity and low fog in high silver chloride tabular grains.

(Objectives of the Invention) The first object of the present invention is to provide a tabular silver chlorobromide emulsion with a high silver chloride content that is stable, highly sensitive, has little fog, and develops rapidly even in rapid processing solutions. is to do;
The second object is to provide a method for producing a tabular silver chlorobromide emulsion with a high silver chloride content using an inexpensively available crystal phase control agent, and the third object is to provide a method for producing a tabular silver chlorobromide emulsion with a high silver chloride content. It is an object of the present invention to provide a method for producing a tabular silver chlorobromide emulsion having a high silver chloride content in an acidic to neutral range where it is easy to suppress.

(Disclosure of the Invention) As a result of intensive studies, the present inventors have found that at least High silver chloride grains in which 80 mol% or more is chloride, and tabular grains with a thickness of less than 0.5 μm, a diameter of 0.5 μm or more, and an aspect ratio of 2 or more account for 50% or more of the projected area of all silver halide grains. It has been found that the above object can be achieved by carrying out halogen conversion after grain formation in a silver halide emulsion containing a large amount of grains.

General formula (E) General formula (II) (A1, A2, A, and A4 represent a group of nonmetallic atoms for completing the nitrogen-containing heterocycle, and each may be the same or different. B is a divalent represents a linking group.m is 0
Or hail 1. R1 and R2 each represent an alkyl group. X represents an anion. n represents 0 or l, and in the case of an inner salt, n is 0. ) General formulas (I) and (IF) will be explained in more detail below.

A, , A, , A, and A represent a group of nonmetallic atoms to complete a nitrogen-containing heterocycle, and may include an oxygen atom, a nitrogen atom, and a sulfur atom (when a benzene ring is fused, The heterocycle composed of A, SA, , A3 and A may have a substituent, and each of them may be the same or different. Examples of the substituent include an alkyl group,
Aryl group, aralkyl group, alkenyl group, halogen atom, acyl group/alkoxycarbonyl group, aryloxycarbonyl group,
Sulfo group, carboxy group, hydroxy group, alkoxy group, aryloxy group, amide group, sulfamoyl group, carbamoyl group, ureido group, amino group, sulfonyl group,
Examples include a cyano group and a nido-membered ring (eg, pyrazine ring, imidazole ring, thiozole ring, oxazole ring, pyrazine ring, torimishin ring, etc.), and a more preferred example is a pyridine ring.

B represents a divalent atom group, and the divalent atom group is alkylene, arylene, alkenylene, -3o! ---
50--0--5--C-S-N- (Rs represents an argyl group, an aryl group, or three hydrogen atoms -,) is a preferable example of B can list alkylene and alkenylene.

RI and R2 represent an alkyl group having 1 to 20 carbon atoms, and RI and R8 may be the same or different.

(Compound example) This is the same as the substituents listed above.

As a preferable example, RI and R8 each have 4 carbon atoms.
-10 alkyl groups, and a more preferred example is a mono- or unsubstituted aryl-substituted alkyl group.

X represents an anion 0 For example, chloride ion, bromide ion, iodine ion, nitrate ion, sulfate ion, P-) luenesulfonate, oxalate, n is 0 &
or 1, and in the case of an inner salt, n is O.

Specific examples of compounds represented by formula (1) or general formula (II) are listed below, but the present invention is not limited only to these compounds.

(11) (12) (13) (lO) 2B, @ 201 @ 2C1# 8- C1- (15) (16) (17) (18) (19) (25) (26) (27) (28) (29) (20) B- (21) C1- (22) 2C1 (23) B- (30) (31) le C1e (Synthesis method of compound) Synthesis of compound (6) In 800 M1 of methanol, 4° 100 g of 4'-dipyridyl and 190 yd of benzyl bromide were added, and the mixture was heated under reflux for 3 hours. After filtering the reaction solution, isopropyl alcohol 8001d was added, and the resulting crystals were collected by filtration to obtain compound (6).

Yield 2116g (90%) 20g of 1,3-di-4-pyridylpropane and 3o-benzyl bromide were added to 400ml of synthetic ethanol, and the mixture was heated under reflux for 2 hours. After filtering the reaction solution, 400% of ethyl acetate was added and the resulting crystals were collected by filtration to obtain a compound.

Yield: 41g (76%) The amount of the compound represented by formula (I) or (II) added is 2X10-' mol to 3 mol per mol of silver halide.
It can be used in the range of XIO-' mole, 2X10-
For the preparation of 'mole-lXl0-' tabular grains, it is preferred that at least a portion of these compounds be present from the beginning of grain formation.

The concentration of chloride when these compounds are present during nucleation is 0. O1 mol/1 or more, preferably 0.02 mol/1 or more, more preferably 0.02 mol/1 or more. It is 35 mol/1 or more.

The temperature at which these particles are formed can range from 10'C to 95C, preferably from 35C to 9O0C.

The pH may be any value, but is preferably in the neutral to acidic range.

The particles of the present invention can be obtained by subjecting host particles formed by the method described above to halogen conversion.

As a method for performing halogen exchange, the host particles and
It can be obtained by mixing potassium bromide, sodium bromide, potassium iodide, bromide salts, iodide salts, etc.

Particularly preferred is a method in which halogen exchange is carried out by mixing with silver halide fine grains having a smaller average grain volume and a higher silver bromide content (mol %) than host grains, and aging.

The silver halide grain size of the fine-grain silver halide emulsion used in the present invention controls the supply rate of bromide ions, and the preferred grain size varies depending on the host grain size and halogen composition, but 0. Those with a diameter of 5μ or less are usually used. More preferably, it is 0.3μ or less.

It is essential that the halogen composition of the fine grain emulsion has a higher silver bromide content than that of the host grains, and preferably a bromide concentration of 50 mol % or more. More preferably, it contains 70 mol% or more of bromide.

The fine grain emulsion may contain silver iodide if necessary. It is also possible to include ions or compounds of heavy metals such as iridium, rhodium, and platinum.

The fine grain emulsion has a silver content of 5% relative to the host silver halide.
It is mixed in a range of 0% to 0.1%.

More preferably 0.2 to 20%, particularly preferably 0,
It is used in a range of 2 to 8%.

The temperature at which the fine grain emulsion, potassium bromide, potassium iodide, etc. are mixed can be freely selected between 30°C and 80°C. Further, the timing of mixing may be before or after the compound of general formula (I) or general formula (II) is removed by the desalting step.

Further, the sensitizing dye can be adsorbed onto the host silver halide before mixing and ripening fine grains, silver halide emulsion, potassium bromide, potassium iodide, etc.

The high silver chloride grains of the present invention produced in this manner refer to grains having a silver chloride content of at least 80 mol % or more. Preferably it is 90 mol%, more preferably 95 mol% or more.

The remainder consists of silver bromide and/or silver iodide, and the content of silver iodide is preferably 5 mol% or less, preferably 1 mol% or less. It is particularly desirable that a layer consisting mainly of silver bromide or silver iodide be localized near the surface of the grains.

Furthermore, in the case of so-called core/shell type particles, it is preferable that the silver chloride content in the core portion is higher than that in the shell portion. For example, particles may be composed of a core portion made of silver chloride and a shell portion made of silver bromide.

The silver halide grains of the present invention have surfaces consisting of (1 1 1) planes, and at least 30% or more, preferably 40% or more, and more preferably 60% or more of the total surface area is (1 1 1).
1 1) Consists of surfaces. The (1 1 1) plane can be quantified from an electron micrograph of the formed silver halide grains.

The silver halide grains of the present invention have a diameter/thickness ratio of 2.
It is more preferably 2 or more and 50 or less, particularly preferably 2 or more and 20 or less, and most preferably 3 or more and IO or less.

The diameter of a silver halide grain herein refers to the diameter of a circle having an area equal to the projected area of the grain. In the present invention, the diameter of the tabular silver halide grains is 0.3 to 5.0μ, preferably 0.
．． It is 5 to 3.0μ.

Also, the thickness is 0. 4μm or less, preferably 0. 3μm
The thickness is more preferably 0.2 μm or less.

The average volume of the particle volume load is preferably 2μ or less. Further, it is preferably 1.0μ or less.

In general, tabular silver halide grains are tabular with two parallel surfaces, and therefore "thickness" in the present invention refers to the distance between the two parallel surfaces constituting the tabular silver halide grains. expressed.

The grain size distribution of the silver halide grains of the present invention may be polydisperse or monodisperse, but monodisperse is more preferable.

The silver halide emulsion of the present invention may be an internal latent image type emulsion or a surface latent image type emulsion.

A silver halide solvent may be used when producing the silver halide grains of the present invention.

Frequently used silver halide solvents include, for example, thiocyanates (e.g., U.S. Pat. No. 2,222,264).
No. 2.448.534, No. 3.320.06
``9, etc.), thioether compounds (for example, U.S. Patent No. 3,271,157, U.S. Patent No. 3,574.628, U.S. Patent No. 3.704.130, U.S. Patent No. 4,297.439)
4,276.347, etc.), thione compounds and thiourea compounds (e.g., JP-A-53-144319, JP-A-53-82408, JP-A-55-77737, etc.)
, amine compounds (for example, JP-A-54-100717, etc.), and these can be used. Ammonia can also be used as long as it does not cause harmful effects.

In the process of silver halide grain formation or physical ripening,
A cadmium salt, a zinc salt, a lead salt, a thallium salt, an iridium salt or a complex salt thereof, a rhodium salt or a complex salt thereof, an iron salt or an iron complex salt, etc. may be present, and an iridium salt or a rhodium salt is particularly preferred.

Silver salt solution (for example, AgN0. aqueous solution) added to accelerate grain growth during production of silver halide grains of the present invention
Preferably, a method is used in which the addition rate, amount, and concentration of a halide solution (for example, an aqueous NaCj solution) are increased according to the addition time.

These methods are described, for example, in British Patent No. 1°335.
No. 925, U.S. Patent No. 3,672,900, U.S. Patent No. 3.
No. 650.757, No. 4.242, . 445, JP 55-142329, JP 55-158124, JP 58-113927, JP 58-113928, JP 5
The descriptions in No. 8-111934, No. 58-111936, etc. can be referred to.

The tabular silver halide grains of the present invention may be left unchemically sensitized, but may be chemically sensitized if necessary.

Chemical sensitization methods include so-called gold sensitization methods using gold compounds (for example, U.S. Pat. Nos. 2,448.060 and 3,32).
No. 0.069) or aggravation methods with metals such as iridium, platinum, rhodium, palladium (e.g., U.S. Pat. No. 2.4)
No. 48.060, No. 2.566.245, No. 2,56
6.263) or a sulfur sensitization method using a sulfur-containing compound (for example, U.S. Pat. No. 2.222.264), a selenium enhancement method using a selenium compound, or a reduction sensitization method using tin salts, thiourea dioxide, polyamines, etc. (eg, U.S. Pat. No. 2,487,850, U.S. Pat. No. 2,518.698, U.S. Pat. No. 2,521,925), or a combination of two or more of these can be used.

In particular, the silver halide grains of the present invention are preferably gold-sensitized, sulfur-sensitized, or a combination thereof.

In addition to the silver halide grains of the present invention, ordinary silver halide grains can be added to the emulsion layer of the silver halide photographic material of the present invention.

In the photographic emulsion of the present invention containing high silver chloride grains according to the present invention, the core high silver chloride grains account for at least 50%, preferably at least 70% of the projected area of all silver halide grains in the emulsion.
Particularly preferably, it is present in an amount of 90% or more.

Even when the photographic emulsion of the present invention and other photographic emulsions are mixed and used, it is preferable to mix them so that 50% or more of the high silver chloride grains according to the present invention are present in the mixed emulsion.

Further, when the photographic emulsion of the present invention and other photographic emulsions are mixed and used, it is more preferable that the emulsion to be mixed is also a high-silver chloride emulsion in which silver chloride accounts for 50 mol % or more.

The emulsion of the present invention may be spectrally sensitized with methine dyes and others. Dyes used include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes,
Included are styryl dyes and hemioxonol dyes. Particularly useful dyes are those belonging to the cyanine dyes, merocyanine dyes, and complex merocyanine dyes. Any of the nuclei commonly used for cyanine dyes can be used as the basic heterocyclic nucleus for these dyes. Namely, pyridine nucleus, oxazoline nucleus, thiazoline nucleus, virole nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus, imidazole nucleus, tetrazole nucleus, pyridine nucleus, etc.; a nucleus in which an alicyclic hydrocarbon ring is fused to these nuclei; and these After the aromatic hydrocarbon ring is fused to the nucleus of Imidazole nuclei, quinoline nuclei, etc. can be applied. These nuclei may be substituted on carbon atoms.

Merocyanine dyes or composite merocyanine dyes include a pyrazolin-5-one nucleus, a thiohydantoin nucleus, a 2-thioxazolidine-2,
A 5- to 6-membered heterocyclic nucleus such as a 4-dione nucleus, a thiazolidine-2,4-dione nucleus, a rhodanine nucleus, and a thiobarbic acid nucleus can be applied.

For example, RESERCHDISCLOSURE I
tea, 17643, page 23, section ■ (December 1978
It is possible to use the compounds described in 1997) or the compounds described in the cited literature.

The timing of adding the dye into the emulsion is an emulsion that has been known to be useful! No. 3,628,969 and US Pat. No. 4,225,666; It is also possible to perform spectral sensitization at the same time as chemical sensitization by adding it at the same time as a chemical sensitizer, as described in JP-A-58-113.928. It can be carried out in advance, or it can be added before the completion of silver halide grain precipitation to start spectral sensitization. Furthermore, it is possible to add these compounds in portions as taught in U.S. Pat. It is also possible to add after chemical sensitization, as described in U.S. Patent No. 4.1.
83.756, at any time during silver halide grain formation.

The amount added is from 4XlO-' to 111 moles of halogenide.
It can be used in axio-” moles, but for a more preferred silver halide grain size of 0.2 to 3 μm, about 5
XIO-' to 2x-3 moles are more effective.

The silver halide emulsion prepared according to the present invention can be used in both color photographic materials and black and white photographic materials.

Examples of color photographic materials include color papers, color side-shadow films, and color reversal films, and examples of black and white photographic materials include X-ray films, films for general photography, and films for printing materials.

There are no particular restrictions on other additives for photographic materials that can be used in the emulsion of the present invention (for example, as described in Research Disclosure magazine).
e) Volume 176 Item 17643 (RD17643
) and same 18'l item 18716 (RD1871
6) can be referred to.

The descriptions of various additives in RD17643 and RD18716 are listed below.Page 26, page 26, page 27, page 26-2, page 651, left, same as above, 650, same as above, right, 9, hardening agent, lO, binder, 11, plasticizer, lubricant. Agent 12 Coating aid, surface active agent 13 Static prevention page 27 Same as above 23
Page 1 Chemical enhancers 2 Brightness enhancers 3 Spectral enhancers, pages 23-24 Super sensitizers 4 Brighteners 5 Anti-fogging agents and stabilizers 6 Light absorbers, filter dyes UV absorbers 7 Anti-staining agents Page 25 Right Column 8 Pigment Surface (& Stabilizer Page 25 Page 25-26 Page 24 Page 24-25 Page 648 Right Column Same as Above Page 648 Right Column ~ Page 649 Right Column Page 649 Right Column Page 649 Right Column ~ 650 Left Column 650 In the left to right columns of the page, antifoggants and stabilizers include azoles (e.g. benzothiazolium salts, nitroimidazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, nitrobenzimidazoles, etc.). indazoles, benzotriazoles, aminotriazoles, etc.) ; mercapto compounds (e.g. mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, mercaptotetrazoles (especially 1-phenyl-5
-mercaptotetrazoles), mercaptopyrimidines, mercaptotriazines, etc.); thioketo compounds such as oxadolinthione;
Hydroxy-substituted (1,3,3a,?)tetraazaindenes), pentaazaindenes, etc.): benzenethiosulfonic acid, benzenesulfinic acid, benzenesulfonic acid amide, etc. can be preferably used.

The color coupler is preferably a non-diffusible one that has a hydrophobic group called a ballast group in its molecule, or a polymerized one.The coupler can be either 4-equivalent or 2-equivalent to silver ions. It may also contain a colored coupler that has a color correction effect, or a coupler that releases a development inhibitor during development (so-called DIR coupler), or the product of the coupling reaction is colorless and has a development inhibitory effect. It may also be a colorless DIR-coupled compound that releases the agent.

For example, magenta couplers include 5-pyrazolone couplers, pyrazolobenzimidazole couplers, pyrazolotriazole couplers, pi,razolotetrazole couplers, cyanoacetylcoumarone couplers, open-chain acylacetonitrile couplers, and yellow couplers.
Examples include acylacetamide couplers (eg, benzoylacetanilides and pivaloylacetanilides), and examples of cyan couplers include naphthol couplers and phenol couplers. As cyan couplers, U.S. Pat.
No. 011, No. 4327173, No. 3446622,
No. 4333999, No. 4451559, No. 4427
Phenolic couplers that grow an ethyl group at the meta-position of the phenol nucleus, described in No. 767, etc., 2.5-diacylamino-substituted phenol-based blurrs, and phenols that have a phenylureido group at the 2-position and an acylamino group at the 5-position. Couplers in which the 5th position of naphthol is substituted with sulfonamide, amide, etc. are preferable because they have excellent image fastness.

In order to satisfy the characteristics required of a photosensitive material, two or more of the above couplers etc. can be used together in the same layer, or the same compound can be added to two or more different layers.
Of course it doesn't matter.

Antifading agents include hydroquinones, 6-hydroxychromans, 5-hydroxycoumarans, spirochromans, p-alkoxyphenols, hindered phenols mainly including bisphenols, gallic acid derivatives,
Typical examples include methylenedioxybenzenes, aminophenols, hindered amine M, and ethers or esters (m-forms) obtained by silylating or alkylating the phenolic hydroxyl group of each of these compounds. Further, metal complexes such as (bissalicylaldoximado)nickel complex and (bis-N,N-dialkyldithiocarbamado)nickel complex can also be used.

For photographic processing of light-sensitive materials using the present invention, any known method can be used, and known processing solutions can be used. Further, the processing temperature is usually selected between 18°C and 50°C, but it may be lower than 18°C or higher than 50°C. Depending on the purpose, development processing to form II images (black and white photographic processing) , or a color photographic process consisting of a development process to form a dye image.

The black and white developer contains known developing agents such as dihydroxybenzene 11 (e.g. hydroquinone), 3-pyrazolidones (e.g. 1-phenyl-3-pyrazolidone), and aminophenols (e.g. N-methyl-p-aminophenol). They can be used alone or in combination.

The color developing solution is generally an alkaline aqueous solution containing a color developing agent.
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.

This ([h.
No. 3.015, No. 2,592゜364, Japanese Unexamined Patent Publication No. 1973-
64933 and the like may be used.

The developer may also contain pH 3 l additives such as alkali metal sulfites, carbonates, borates, and phosphates, development inhibitors such as bromides, iodides, and antifoggants,
Antifoggants and the like can be included. If necessary, water softeners, preservatives such as hydroxylamine, organic solvents such as benzyl alcohol, diethylene glycol, polyethylene glycol, quaternary ammonium salts, Tjta accelerators such as amines, dye-forming couplers, competitive couplers, Fogging agents such as sodium boron hydride, auxiliary developers such as 1-phenyl-3-pyrazolidone, viscosity imparting agents, polycarboxylic acid chelating agents described in U.S. Pat. No. 4,083°723, OLS 2 ，
622.950, etc., may also be included.

When color photographic processing is performed, the photographic light-sensitive material after color development is usually bleached. The bleaching process may be performed simultaneously with the fixing process or separately. Examples of bleaching agents include iron (+11), cobalt (m), and
(Vl), tJA (II), peracids, quinones, nitroso compounds, etc. For example, ferricyanide, dichromate, iron (Il)
l) or organic complex salts of cobalt (Ill), such as aminopolycarboxylic acids such as ethylenediamine tetracomplex, nitrilotriacetic acid, 1,3-diamino-2-propatoltetraacetic acid, or citric acid, tartaric acid, malic acid, etc.
Complex salts of i-acids; persulfates, permanganates; nitrosophenols, etc. can be used. Among these, potassium ferricyanide, sodium ethylenediamine tetracomplex iron(I[I), and ammonium iron(I[I) ethylenediamine tetracomplex] are particularly useful. Ethylenediamine tetracomplex iron(III) complex salts are useful in both stand-alone bleach solutions and -bath bleach-fix solutions.

For bleaching or bleach-fixing solutions, U.S. Patent 3,042.52
No. 0, No. 3,241,966, Special Publication No. 45-8506
Bleaching accelerators described in Japanese Patent Publication No. 45-8836, etc.
In addition to the thiol compound described in JP-A-53-65732, various additives can also be added. Further, after the bleaching or bleaching/fixing treatment, a water washing treatment or a stabilizing bath treatment may be sufficient.

The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto.

(Example 1) Silver chlorobromide emulsion (1-A) was prepared as follows.

Solution (1) Solution (2) Solution (3) Solution (4) Solution (5) Add solution (2) and solution (3) simultaneously over 10 minutes while vigorously stirring solution (1) kept at 35°C. did.

After further raising the temperature to 75℃, solution (4) and solution (5)
were added simultaneously over 30 minutes.

After washing and desalting this emulsion with water using the usual flocculation method and adding gelatin, the pH was adjusted to 6°4 and the pAg to 7 at 40°C.
．． 5 to obtain a tabular silver chloride emulsion (1-A).

The prepared silver chloride emulsion had a thickness of 0. 80% or more (projected area) of tabular grains with a diameter of less than 5 μm, a diameter of 0.5 μm or more, and an aspect ratio of 2 or more consisting of parallel (111) planes, and the average projected area of the tabular grains is 1. 8μ
M, its average thickness was 0.22 μm1, and its average aspect ratio was 6.9.

This (1-A) and silver bromide ultrafine grain emulsion (grain size 0.
05 μm) was added in an amount containing 1 mo1% of silver bromide based on silver chloride, and the mixture was aged at 60° C. for 10 minutes to obtain (1-B).

An emulsion (1-C) was obtained which differed from (1-B) only in that 3 mo1% of silver bromide ultrafine grain emulsion was added.

An emulsion (1-D) was obtained which differed from (1-B) only in that 6 mo1% of silver bromide ultrafine grain emulsion was added.

(1-A) is a silver bromoiodide ultrafine grain emulsion (AgBrssl).
l, average grain size 0.05 μm) for silver chloride,
3 mo1% of silver bromide was added thereto and aged at 60°C for 10 minutes to obtain (1-E).

Furthermore, (1-A) and 2,5M potassium bromide were added in an amount containing 1 mo1% potassium bromide based on silver chloride, and 60
It was aged for 10 minutes at °C to obtain (2-B).

An emulsion (2-C) was obtained which differed from (2-B) only in that 3 mo1% of potassium bromide was added.

An emulsion (2-0) was obtained which differed from (2-B) only in that 6 mo1% of potassium bromide was added.

An aqueous solution containing 2.5 mol/It potassium bromide and 0.05 mol/L potassium iodide was added to the emulsion (1-A) in an amount containing 0.03 mol potassium bromide per mol silver chloride. 6
After aging at 0°C for 10 minutes, (2-E) was obtained.

Silver chloride cubic grains were prepared as a comparative emulsion by a method that did not contain compound example αυ. The average particle diameter of the prepared particles is 0.75 μm, and the volume per particle is the same as that of the tabular particles. This silver chloride cubic emulsion is designated as (3-A).

This (3-A) and silver bromide ultrafine grain emulsion (grain size 0,
05 μm) was added in an amount containing 1 mo1% of silver bromide based on silver chloride, and ripened at 60° C. for 10 minutes to obtain (3-B).

An emulsion (3-C) was obtained which differed from (3-B) only in that 3 mo1% of silver bromide ultrafine grain emulsion was added.

An emulsion (3-D) was obtained which differed from (3-B) only in that 6 m01% of silver bromide ultrafine grain emulsion was added.

(3-A) is a silver bromoiodide ultrafine grain emulsion (AgBrssl).
! , average grain size 0.05 μm) for silver chloride,
3 mo1% of silver bromide was added thereto and aged at 60°C for 10 minutes to obtain (3-E).

Emulsions (1-A) to (1-E), (
2-B) to (2-E) and (3-A) to (3-E) were added to a triacetyl cellulose film support with the additives shown in Table 1, and an emulsion and a protective layer were applied. , sample 1
01-105.202-205.301-305 were obtained.

Table 1 (Emulsion layer) Emulsion Each of the above emulsions Coated silver amount 2. Og/ffl Gelatin 1.3g/I Stabilizer-4-
Hydroxy-6-tyl-1,3゜3a,7-titrazaindene Thickener: Potassium poly-p-styrenesulfonate Hardener: l,2-bis(vinylsulfonylacetamidoethane) (Surface protective layer) Gelatin 1.0g /rrr Coating aid: pCsH+t-C5H+-(OCHtCH*)s
sOsNa preservative: 3-benzisothiazolidone Matting agent: Polymethyl methacrylate fine particles Each sample was exposed to 4000 lux mercury light for 1150 seconds through an optical wedge, and heated at 35°C using an FPM-4000 automatic processor manufactured by Fuji Photo Film ■. The film was developed using RD-III developer specified by Fuji Photo Film (1) under processing conditions of 90 seconds.

These evaluation results are shown in Table 2.

Note that the sensitivity is 0.0% from the fog value for each sample.
3. Relative sensitivity is shown as a relative value of the reciprocal of the exposure amount required to provide a high optical density, with the sensitivity of sample 101 set as 100.

As is clear from Table 2, the photographic silver halide emulsion according to the present invention has good sensitivity with little fog. In particular, samples (102), (103) using emulsions (1-B), (1-C), (1-D), or (1-E) which have been halogen-exchanged with silver bromide or silver iodobromide fine grains, (
104) or (105) is preferred because of its high sensitivity.

Claims (1)

[Claims] 1) Consists of silver halide grains in which at least 80 mol% is silver chloride, and has a thickness of less than 0.5 μm and a diameter of 0.5 μm.
In the method for producing a photographic silver halide emulsion in which tabular grains having an aspect ratio of 2 or more account for 50% or more of the projected area of all silver halide grains, the silver halide grains have the following general formula (I) or the general formula 1. A method for producing a silver halide photographic emulsion, which comprises forming grains in the presence of at least one compound of formula (II), and carrying out halogen conversion after the grain formation. 2) After forming the silver halide grains in which 80 mol % or more is silver chloride, silver halide fine particles having a smaller average grain volume and a higher silver bromide content (mol %) than the above grains are added to remove halogen. A method for producing a silver halide photographic emulsion according to claim 1, which comprises converting a silver halide photographic emulsion. General formula (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ General formula (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. Represents an atomic group, each of which may be the same or different. B represents a divalent linking group. m represents 0 or 1. R_1 and R_2 each represent an alkyl group. X represents an anion. n represents It represents 0 or 1, and n is 0 when it is an inner salt.)