JPS5851253B2 - Method for producing silver halide photographic emulsion - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a silver halide photographic emulsion that is used to obtain photographic images by developing and fixing, and more specifically relates to a method for producing a silver halide photographic emulsion that is used to obtain a photographic image through a development and fixing process. The present invention relates to a method for producing a silver oxide photographic emulsion.

It is known that rhodium salts are added mainly during grain formation in order to obtain high contrast silver halide emulsions.

Rhodium salts are also extremely useful in the production of silver halide photographic emulsions because the gradation of photographic emulsions can be adjusted by increasing or decreasing the amount of rhodium salts added.

Silver halide photographic emulsions whose contrast has been enhanced by the addition of rhodium salts have significantly lower sensitivity than emulsions that do not use rhodium salts; A serious drawback was that the sensitization caused sensitization and softening during storage.

To eliminate this drawback, for example US Pat.
As described in No. 09, a method is known in which a cadmium salt is added during the manufacturing process of a silver halide photographic emulsion containing a rhodium salt.

However, since photosensitive materials containing cadmium salts leak cadmium salts into the developing, fixing, and washing baths in photographic processing, there are problems such as environmental pollution and adverse effects on the human body, and their use is therefore undesirable.

Furthermore, as described in JP-A-50-23618, a method is known in which a water-soluble rhodium salt and a nucleic acid decomposition product are added before the first ripening of a silver halide photographic emulsion is completed.

Adding a nucleic acid decomposition product to a silver halide photographic emulsion is a well-known technique, and its effect is to inhibit ripening.

That is, if the nucleic acid decomposition product is added before the end of the first ripening (physical ripening), the growth of silver halide grains will be suppressed, leading to fine grain formation, changes in crystal habit, etc.

This inevitably results in large changes in photographic properties.

Furthermore, nucleic acid decomposition products added before the completion of the first ripening remain in the emulsion even after desalting, and during the second ripening (chemical ripening), they affect the formation and growth of photosensitive nuclei, reducing sensitivity. let

An object of the present invention is to provide a method for producing a silver halide photographic emulsion that has high contrast and maintains stable photographic properties, particularly gradation, during storage.

Still another object of the present invention is to provide a method for producing a high contrast silver halide photographic emulsion that is free from environmental pollution and has good storage stability without affecting other photographic properties.

The object of the present invention is to add a rhodium salt at any time before the completion of the first ripening to a silver halide photographic emulsion containing at least 30 moles of silver chloride, and to add rhodium salt at any time after desalting to a silver halide photographic emulsion containing silver chloride, 10 per mole of silver of the compound represented by (I) or (n) or the compound that forms a redox system with it and can form a compound represented by general formula (I) or (I[) in a photographic emulsion.
It has been found that this can be achieved by adding -1 to 10-5 moles and sulfur sensitization.

In the formula, the person is a divalent aromatic group, such as a phenylene group (e.g., 1,4-phenylene group, 1,2-phenylene group),
Naphthylene group (for example, ■, 2 naphthylene group, 2,3
-naphthylene group, ■, 4-naphthylene group, 1,5-naphthylene group, 1,8-naphthylene group), anthrylene group (e.g. 9°10-antrylene group, 1,2-antrylene group, 1,4-antrylene group), etc. Hail.

Preferred are phenylene or anthrylene groups, particularly preferred are 1,4-phenylene or 9°10-anthrylene groups.

These groups include alkyl groups having 1 to 4 carbon atoms (e.g. methyl group, ethyl group), alkoxy groups having 1 to 4 carbon atoms (e.g. methoxy group, ethoxy group), halogen atoms (e.g. chlorine atom, bromine atom), carboxy group, phenyl group,
It may be further substituted with a sulfo group or the like.

B represents an amino group.

The amine group may be an unsubstituted amino group or may be substituted.

For example, methylamino group, dimethylamino group, ethylamino group, diethylamino group, isopropylamino group,
butylamino group, di-n-octylamino group, di-n-
Heptadecylamino group, allylamino group, β-hydroxyethylamino group, (β-sulfonamidoethyl)amino group, β-chloroethylamino group, β-cyanoethylamino group, γ-sulfopropylamino group, benzylamino group, p -Represents a sulfobenzylamino group, etc.

The rhodium salt used in the present invention includes not only simple salts but also complex salts, and conventionally known salts are used, and rhodium chloride, rhodium trichloride, rhodium ammonium chloride, etc. are typically used.

Although it is necessary to add the rhodium salt before the end of the first ripening, it is particularly desirable to be present during grain formation.

The amount of rhodium salt added can be freely changed depending on the required gradation, but it ranges from 10-9 to 10-9 mol per mol of silver.
A range of 6 moles is particularly useful.

It is known that all the compounds having the general formula (I) or (II) used in the present invention act as reducing agents, and even in silver halide photographic emulsions, they constitute a redox system under a certain equilibrium. It is a compound that has

For this reason, oxidized and reduced forms exist even in silver halide photographic emulsions.

Also when a compound whose reduced form corresponds to a compound represented by general formula (I) or (n) (i.e., an oxidized form of a compound represented by formula (I) or (II)) is added to a silver halide photographic emulsion, Similarly, since it constitutes a redox system, an oxidized form and a reduced form exist in the photographic emulsion.

Therefore, it was confirmed that a similar effect can be obtained even when such a compound is added to a silver halide photographic emulsion having a higher contrast than a rhodium salt (as shown in Example (2)).

The compound represented by the general formula (I) or (II) used in the present invention or the compound constituting the redox system in the emulsion and whose reduced form is represented by the general formula (1) or (II) is a silver halide photographic emulsion. It can be added at any time after the desalination step in production, specifically, during the second (chemical) ripening or before the end of the first ripening.

The amount to be added varies depending on the amount of rhodium salt used, but a range of 10' mol to 10' mol per 1 mol of silver is effective, and a range of 10-5 mol to 10-2 mol is particularly effective. It is.

In addition, these compounds cause negligible changes in photographic properties such as sensitivity, gradation, fog, etc. within the above range of addition amounts.

The high-contrast silver halide emulsion with improved storage stability according to the present invention is stable over natural aging and aging under harsh conditions, and is sufficiently satisfactory to provide a shelf life of conventional photographic film exceeding, for example, one year. It was something that should have been done.

Next, typical compounds represented by general formula (I) or (n) or their oxidized products used in the present invention are shown below.

However, the compounds in the present invention are not limited to these.

Methods for synthesizing these compounds are known.

The invention applies to silver halide emulsions containing at least 30 moles of silver chloride.

The remaining silver halide is silver bromide or 5mol1% of silver bromide.
Preferably, the silver iodide does not exceed .

If silver iodide exceeds 5 mo1%, sufficient contrast cannot be achieved.

The average grain size of silver halide grains in photographic emulsions (the grain size is the grain diameter for spherical or approximately spherical grains, and the average length for cubic grains, expressed as an average based on the projected area) is particularly important. Although it does not matter, it is preferably 3μ or less.

The particle size distribution may be narrow or wide.

The silver halide grains may have different phases inside and on the surface, or may have a uniform phase.

Further, the particles may be particles in which a latent image is mainly formed on the surface, or may be particles in which a latent image is mainly formed inside the particles.

The photographic emulsion of the present invention is prepared by P. Glafkides, JCh
imie et Physique Photogra
phiqueJ (published by Paul Monte1, 196
7 years) G, F.

"Photographic Emul" by Duffin
sionChemistry l (T'he Foc
al Press, 1966), V, L, Ze
likman et al 1nakingand C
oating Photographic Emuls
ionJ (The Focal Press, 196
4), etc.).

That is, any of the acidic method, neutral method, ammonia method, etc. may be used, and the method for reacting the soluble silver salt and soluble halogen salt may be any one-sided mixing method, simultaneous mixing method, or a combination thereof.

It is also possible to use a method in which particles are formed in an excess of silver ions (so-called back-mixing method).

As one type of simultaneous mixing method, a method in which the pAg in the liquid phase in which silver halide is produced can be kept constant, that is, a so-called controlled double jet method can also be used.

According to this method, a silver halide emulsion having a regular crystal shape and a nearly uniform grain size can be obtained.

Two or more types of silver halide emulsions formed separately may be mixed and used.

Gelatin is usually used as a binder or protective colloid in photographic emulsions, 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 and carboxymethyl cellulose; sugar derivatives such as agar, sodium alginate, and starch derivatives; polyvinyl alcohol partial acetals; A wide variety of synthetic parent polymeric materials can be used, such as single or copolymers of poly-N-vinylpyrrolidone, polyacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole, and the like.

As the gelatin, in addition to lime-treated gelatin, acid-treated gelatin may be used, and gelatin hydrolysates and gelatin enzymatically decomposed products can also be used.

Examples of gelatin derivatives include gelatin, acid halides, acid anhydrides, acid esters, isocyanates, bromoacetic acids, alkanesultones, vinyl sulfonamides,
Those obtained by reacting various compounds such as maleimide compounds, acrylonitriles, polyalkylene oxides, and epoxy compounds are used.

A specific example is U.S. Pat. No. 2,594,293, 2,61
No. 4,928, No. 2.763,639, No. 3,118,7
No. 66, No. 3,132,945, No. 3,186,846, No. 3,312,553, British Patent No. 861,414,
No. 1,033,819, Special Publication No. 39-5514, No. 4
No. 2-26845, etc.

The soluble salts are usually removed from the emulsion after precipitation or physical ripening, and the long-known Nodel water washing method, which involves gelatinizing gelatin, may be used for this purpose. Precipitation methods (flocculation) using inorganic salts (e.g. sodium sulfate), anionic surfactants, anionic polymers (e.g. polystyrene sulfonic acid) or gelatin derivatives (e.g. aliphatic acylated gelatin, aromatic acylated gelatin, etc.) ) may be used.

The process of removing soluble salts may be omitted.

The silver halide emulsion of the present invention is chemically sensitized with a sulfur compound, and if necessary, other chemical sensitization methods are used in combination.

For horizontal yellow sensitization method or other chemical sensitization method, H, F
r1eser edition “Die Grundlagen der
photography
mit Silberkalogeniden, J.
(Akademi 5che Ver lagsge
sel 1schaft *1968) and other known methods can be used.

That is, a sulfur sensitization method using a compound containing sulfur that can react with silver ions or active gelatin, a reduction sensitization method using a reducing substance, a noble metal sensitization method using gold or other noble metal compounds, etc. are used alone or in combination. be able to.

As the sulfur sensitizer, thiosulfates, thioureas, thiazoles, rhodinides, and other compounds can be used, specific examples of which are described in U.S. Pat. No. 1,574,944.
No. 2.410,689, No. 1,725,934, 2
, 278,947, 3,501,313, 2,72
No. 8,668 and No. 3,656,955.

As a reduction sensitizer, stannous salt 1. Amines, hydrazine derivatives, formamidine sulfinic acid, silane compounds, etc. can be used, and specific examples thereof are given in U.S. Pat.
, 487,850, 2,419,974, 2,41
No. 9,975, No. 2,518,698, No. 2,521,9
No. 25, No. 2,521,926, No. 2,983,610, and No. 2,694,637.

For noble metal sensitization, in addition to total complex salts, complex salts of metals in Group I of the periodic table, such as platinum, iridium, and palladium, can be used; specific examples include British Patent No. 570,393;
It is described in US Pat. No. 2,399,083, US Pat. No. 2,448,060, etc.

The photographic emulsion of the present invention can contain various compounds for the purpose of preventing fog during the manufacturing process, storage, or photographic processing of the light-sensitive material, or for stabilizing photographic performance.

i.e. benzothiazoles, amino-, nitro- or halogen-substituted benzimidazoles, nitro- or amino-substituted indazoles, triazoles, unsubstituted or nitro-halogen- or alkyl-substituted benzotriazoles, mercapto. Thiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles,
Compounds belonging to azoles and azines, such as mercaptotriazoles, mercaptotetrazoles, mercaptopyrimidines, and thioketo compounds such as thiazolethione; Azaindenes, such as nitriazaindenes, tetraazaindenes, and pentaazaindenes; benzenesulfinic acid; Polymers such as benzenesulfinamide, benzenethiosulfonic acid, thioctic acids, phenazines, iodonium salts, iodates, polyvinylpyrrolidone, halogen-substituted divalent fatty acids, noble metal salts (e.g. compounds such as gold, platinum, palladium, iridium, etc.) ), aminostilbene compounds having a heterocycle, etc. can be used alone or in combination.

Specific examples of these compounds are provided in U.S. Patent No. 2,131,03.
No. 8, No. 2,271,229, No. 2,503,861,
No. 2,403,927, No. 2.453,087, 2,4
No. 32,864, No. 3,051,570, 2.824,
No. 001, British Patent No. 403,789, 452,043
No., Special Publication No. 35-17377, U.S. Patent No. 2.444,
No. 605, No. 2,444,606, No. 2,450,397
No. 2,933,388, No. 2,713,541, Japanese Patent Publication No. 345647, No. 35-17378, U.S. Patent No. 2
．． No. 057,764, No. 2,394,198, No. 2,94
No. 8,614, No. 3.128,186, No. 3,128,1
No. 87, British Patent No. 851,774, German Patent No. 1,10
No. 7,508, No. 645,035, Belgian Patent No. 575
, No. 907, Special Publication No. 43-4136, No. 43-413
No. 4, U.S. Pat. No. 2,282,005, 2.675,3
No. 14, No. 2,472,631, No. 2,552,229, No. 2.552,230, No. 2,566,245, 2,
No. 566,263, No. 2.597,856, etc.

Various chelating agents such as dihydroxybenzoic acid, gallic acid, dimethylglyoxime, and ethylenediaminetetraacetic acid may be added to the emulsion to prevent fogging and desensitization caused by metal ions.

Examples of these are U.S. Patent No. 2,691,588, British Patent No. 623,448, British Patent No. 952,162,
No. 133, Japanese Patent Publication No. 43-4941, U.S. Patent No. 3,45
No. 7,079, etc.

The photographic emulsions of this invention may be spectrally sensitized with methine dyes and others.

The pigments used are cyanine pigment, merocyanine pigment,
Complex cyanine dye, complex merocyanine dye, hollow polar cyanine dye, hemicyanine dye, styryl dye,
Included are hemioxonol dyes.

Particularly useful dyes are those belonging to the cyanine dyes, merocyanine dyes and complex merocyanine dyes.

As the basic five-section ring nucleus constituting the molecules of these dyes, any of the nuclei commonly used for cyanine dyes can be used.

That is, pyrroline nucleus, oxazoline nucleus, thiazoline nucleus, pyrrole nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus, imidazole nucleus, tetrazole nucleus, pyridine nucleus, nuclei in which an alicyclic hydrocarbon ring is fused to these nuclei, and these Nuclei in which an aromatic hydrocarbon ring is fused to the nucleus, namely indolenine nucleus, benzindolenine nucleus, indole nucleus, benzoxazole nucleus, naphthoxazole nucleus, benzothiazole nucleus, naphthothiazole nucleus, benzoselenazole nucleus, naphthoselenazole nucleus , benzimidazole nucleus, naphthimidazole nucleus, quinoline nucleus, etc. are applicable.

These nuclei have substituents on carbon atoms, such as alkyl groups, alkoxy groups, hydroxy groups, carboxy groups, alkoxycarbonyl groups, acyl groups, amino groups, alkylamino groups, dialkylamino groups, acylamino groups, (sulfonylamino groups) ), acyloxy groups, substituted alkyl groups, such as haloalkyl groups such as trifluoromethyl groups, aryl groups (such as phenyl or naphthyl groups), substituted aryl groups (such as p-sulfophenyl groups), cyano groups, or It may be substituted with a halogen atom (for example, a chlorine atom).

In the case of merocyanine dyes or composite merocyanine dyes, the acidic nucleus constituting the dye molecule is birapurin-5.
-on nucleus, hydantoin nucleus, thiohydatoin nucleus, 2-thioxapridine-2,4 dione nucleus, thiazolidine-2
, 4-dione nucleus, rhodanine nucleus, thiobarbic acid nucleus, and the like, 5- to 6-membered heterozygotic nuclei having ketomethylene bonds can be applied.

Spectral sensitization of photographic emulsions produced by the method of the present invention includes JP-A Nos. 49-134315, 5023220, 5
It is advantageous to use the sensitizing dyes described in No. 0-33828.

The photographic emulsion of the present invention may contain an inorganic or organic hardening agent.

Examples of inorganic hardeners include chromium salts such as chromium alum and chromium acetate, and zirconium salts; examples of organic hardeners include aldehydes such as formaldehyde glyoxal and geltaraldehyde, N,N'-dimethylol urea, and methylol. N-methylol compounds such as dimethylhydantoin, dioxane derivatives such as 2,3-dihydroxydioxane, 1,4-butylene-bis-2,3-
Compounds having epoxy groups such as epoxypropyl ether, ethyleneimine compounds such as 2,4.6-dolyethyleneimino-S-)riazine, hexamethylene-N, N'-bisethyleneurea, 1,3. ．． Active vinyl compounds such as 5-triacryloylhexahydro-5-triazine, divinyl ketone, divinyl sulfone, methylene bismaleimide, compounds having active halogens such as 2,4-dichloro-6-hydroxy-5-triazine,
Mucohalogen acids such as mucochloric acid, mucobromic acid, and mucophenoxychloric acid, bismethanesulfonic acid esters such as 1,2-di(methanesulfonoxy)ethane, sulfonyl compounds such as bisbenzenesulfonyl chloride, n-propylarylcarbodiimide Carbodiimides, isocyanates, isoxazoles, etc., or polymer hardeners such as dialdehyde starch, 2-chloro-6-hydroxy-s-)'J azinylated gelatin, etc., may be used alone or in combination. I can do it.

Precursors of hardeners, such as sulfite aldehyde adducts, may also be used.

Specific examples of these can be found in U.S. Pat. No. 1,870,354, 2.
No. 080,019, No. 2,579,801, No. 2,725
, No. 295, No. 2.726, No. 162, No. 2,732, 31
No. 6, No. 2,983,617, No. 2.992,109,
No. 3,017,280, No. 3,057,723, 3.0
No. 47,394, No. 3,103,437, No. 3,325,
No. 287, No. 3,380,829, No. 3,362,827
British Patent Nos. 676.628, 825,544, 9
No. 94,869, No. 1,167,207, West German Patent No. 87
No. 2,153, No. 1,090,427, Special Publication No. 3471
No. 33, No. 46-1872, No. 46-38713, etc.

Various known surfactants can be added to the photographic emulsion of the present invention as a coating aid, or for the purpose of preventing static electricity, improving slipperiness, and other purposes.

For example, nonionic surfactants such as saponin, polyethylene glycol, polyethylene glycol-polypropylene glycol condensates, polyalkylene glycol ethers, polyalkylene glycol esters, polyalkylene glycol amides, and alkyl carboxylates, alkyl sulfonates, alkylbenzenes, etc. Anionic surfactants such as sulfonates, alkylnaphthalene sulfonates, alkyl sulfates, N-acylated-N-alkyl taurines, maleobimarates, and the like can be used.

Specific examples of these surfactants are given in British Patent No. 1.198.
, 450, 1,077.317, U.S. Patent No. 3.29
No. 4,540, No. 2,240,472, No. 2,831,7
No. 66, No. 3.068,101, No. 2,739,891, No. 2,359,980, No. 2.409,930, 2,
No. 447,750, No. 2,823,123, 3.415
, No. 649, West German Patent No. 1,942,665, etc.

Alternatively; for example, use of an amphoteric surfactant as described in British Patent No. 1,159,825, Japanese Patent Publication No. 40-378, Japanese Patent Publication No. 48-43924, US Patent No. 3,726,683, etc. You can also do it.

U.S. Patent Nos. 3,589,906 and 3,666,478
No. 3.754,924, West German Patent Application No. 1,961
Fluorine-containing surfactant compounds described in , No. 638, JP-A No. 50-59025, etc. can also be used.

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

For example, alkyl (meth)acrylate, alkoxyalkyl (meth)acrylate, glycidyl (meth)acrylate, (meth)acrylamide, vinyl ester (
(for example, vinyl acetate), acrylonitrile, olefins, styrene, etc. alone or in combination, or combinations thereof with acrylic acid, methacrylic acid, α- and β-unsaturated dicarboxylic acids, hydroxyalkyl methacrylates, sulfoalkyl acrylates, styrene sulfonic acids, etc. Polymers having combinations as monomer components can be used.

Specific examples thereof include U.S. Pat. No. 2,376,005, U.S. Pat.
No. 739,137, No. 3,411,911, No. 3, 4
No. 88,708, No. 3,635,715, No. 3,60
No. 7,290, No. 3,645,740, British Patent 1,
No. 186,699 and No. 1,307,373.

The photographic emulsion of the present invention can be photodeveloped (after photoprinting or exposure).
The emulsion is not an emulsion intended for photo development, but is developed with a developer containing a developing agent in an amount sufficient for development by itself, and then fixed with a fixer containing a silver halide solubilizer. The purpose is to obtain images.

Photographic emulsions which are intended for rapid processing by developing the photographic layer with an "activating" processing solution consisting of an alkali or alkaline salts and containing no substantial amount of developing agent are not covered by this invention.

Any known method can be used for photographically processing the layers comprising the photographic emulsion of the present invention.

Known processing liquids can be used, and the processing temperature is usually from 18°C to 50°C, or can be lower than 18°C or higher than 50°C.

Development processing to form silver images depending on the purpose (black and white photographic processing)
Alternatively, any color photographic process consisting of a development process to form a dye image can be applied.

The developer used in black-and-white photographic processing can contain known developing agents.

Examples of developing agents include dihydroxybenzenes (e.g., hydroquinone, chlorohydroquinone, methylhydroquinone, etc.), 3-virapritones (e.g., 1-phenyl-3-pyrazolidone, 1-phenyl-4-methyl-3-pyrazolidone, etc.), and aminophenols. (e.g. 0-aminophenol, p-aminophenol, N
-Methyl-p-aminophenol, 2,4-diaminophenol, etc.), pyrogallol, ascorbic acid, ■-
Aryl-3-pyrazolines (e.g., 1-(p-hydroxyphenyl)-3-aminopyrazoline, 1-(p-
-methylaminophenyl)-3-aminopyrazoline), etc. can be used alone or in combination.

The developer may also contain preservatives (e.g. sulfites, bisulfites, ascorbic acid, etc.) and alkaline agents (
hydroxides, carbonates, etc.), pH buffering agents (e.g. carbonates,
borates, boric acid, acetic acid, citric acid, alkanolamines, etc.), solubilizing agents (e.g. polyethylene glycols, their esters, alkanolamines, etc.), sensitizers (e.g. nonionic surfactants containing polyoxyethylene chains) agents, quaternary ammonium compounds, etc.), surfactants, antifoggants (e.g., halides such as potassium bromide and sodium bromide, nitroindazole, nitrobenzimidazole, benztriazole, benzthiazole, tetrazoles, thiazoles, etc.) ), chelating agents (e.g., ethylenediaminetetraacetic acid, or its alkali metal salts, nitrilotriacetates, polyphosphates, etc.), development accelerators (e.g., U.S. Pat. No. 2,304,02
No. 5, compounds described in Japanese Patent Publication No. 47-45541, etc.)
, a hardening agent (eg, geltaraldehyde, etc.), or an antifoaming agent can be added.

A so-called "lith type" development process can be applied to the photosensitive material of the present invention.

"Lith-type" development processing is a development process in which dihydroxybenzenes are usually used as a developing agent and a low sulfite ion concentration is used for photographic reproduction of line images or halftone dot photographic development. (Details are described in Mason, Photography, Processing, Chemistry J (1966), pp. 163-165).

EXAMPLES The present invention will be explained in more detail with reference to Examples below.

Example 1 A silver chloroiodobromide emulsion (silver iodide 0.00.
4 molar ratio and 17 molar ratio of silver bromide) were prepared.

An aqueous solution of sodium chloride, potassium bromide, and potassium iodide containing rhodium trichloride equivalent to 10-7 mol/mol of silver and an aqueous solution of silver nitrate were continuously added to an aqueous gelatin solution at 63°C with stirring. Silver chloroiodobromide grains were formed.

After washing and desalting the emulsion with water, the emulsion was sensitized to sulfur and gold according to a conventional method.

Dimethine merocyanine dye was added to this emulsion for spectral sensitization, and 2-methyl-4-hydroxy-1,3 was used as a stabilizer.
, 3at7-titraazaindene was added for 2 minutes, and on the other hand, the compound example 1 was added at a concentration of 5 x 1.0 per mole of silver.
-3 mol was added to the other, and no additive was added to the other, and each was coated and dried on a polyethylene terephthalate base.

Each of the obtained samples was given step yellowing in accordance with a conventional method, and then developed at 20° C. for 4 minutes with a developer having the following formulation.

Developer Monomethyl para-aminophenol (methol) sulfate 3.1.9
Anhydrous sodium sulfite 4.5 g Hydroquinone 12 g Sodium carbonate (monohydrate) 799: Bromkali
Add 1.9g water
31 This test was conducted on samples immediately after coating and on samples left at room temperature and humidity for 30 days.

For comparison, an emulsion prepared without rhodium salt was also tested using the same procedure.

The results obtained are shown in Table 1.

The contrast was expressed as the average gradation for the exposure amount giving densities of 1.5 and 0.1.

Example 2 A silver chloroiodobromide emulsion (1 mole of silver iodide, 60 moles of silver bromide) was prepared using a double jet mixing method.

An aqueous solution of sodium chloride, potassium bromide, and potassium iodide containing rhodium ammonium chloride equivalent to 1.7 X 10-8 mol/1 mol of silver and an aqueous solution of silver nitrate were stirred into an aqueous gelatin solution at 55°C. It was added continuously to form silver chloroiodobromide grains.

After washing the emulsion with water and desalting, it was sensitized to sulfur and gold according to a conventional method.

Dimethine merocyanine dye was added to this emulsion for spectral sensitization, and 2-methyl-4-hydroxy-”y3 was used as a stabilizer.
p3a7-titraazaindene was added and the mixture was divided into two parts. Compound Example 1-r was added in 3×10' mol per mol of silver to one part, and no additive was added to the other part, and each was coated on a polyethylene terephthalate base and dried.

The obtained sample was subjected to exactly the same test as in Example 1, and the results shown in Table 2 were obtained.

Example 3 Grain formation was carried out in the same manner as in Example 1, and after washing with water and desalting, sulfur and gold sensitizers were added, the emulsion was divided into two, and each was ripened.

To one of them, 4.9 x 10' mol of Compound Example 2-g per 1 mol of silver was added in the late stage of after-ripening, and to the other, it was not added and each was after-ripened at 60°C for 40 minutes to obtain two types of emulsions. .

Each of these emulsions was spectrally sensitized by adding dimethine merocyanine dye, 2-methyl-4-hydroxy-1,3,3a, 7-titraazaiintene was added as a stabilizer, and each was coated on a polyethylene terephthalate base and dried. did.

The obtained sample was subjected to exactly the same test as in Example 1, and the results shown in Table 3 were obtained.

It can be seen that the samples according to the present invention show small changes in sensitivity and contrast before and after being left for 30 days.

Claims (1)

[Scope of Claims] 1. A silver chlorobromide photographic emulsion containing at least 30 molar silver chloride, or a silver iodochlorobromide photographic emulsion containing at least 30 molar silver chloride and not more than 5 molar silver iodide. In the method for producing an emulsion, an amount of rhodium salt capable of increasing high contrast is added at any time before the end of the first ripening, and a compound represented by the following general formula (I) or (It) is added at any time after desalting. , or constitutes a redox system with it and contains general formula (I) or (I) in a photographic emulsion.
f) Addition of 10-1 to 10-5 mol per mol of silver of a compound capable of producing the compound shown in f), and sulfur sensitization, to achieve high contrast and gradation stability during storage. An improved method for producing a silver halide photographic emulsion which is developed and fixed in a developer containing an effective amount of a developing agent. [In the formula, human represents a divalent aromatic group, and B represents an unsubstituted or substituted amino group. ]