JPH02139536A - Silver halide photographic sensitive material having improved shelf life - Google Patents

Abstract

PURPOSE:To reduce deterioration during storage and to enhance sensitivity and suitability to rapid processing at a high temp. by forming at least one of silver halide emulsion layers with a silver halide emulsion subjected to coagulation treatment with a gelatin deriv. after chemical aging. CONSTITUTION:A silver halide emulsion passed through a desalting stage after crystal growth and subjected to satisfactory chemical aging with a chemical sensitizer is subjected to coagulation treatment again a gelatin deriv. and at least one of silver halide emulsion layer is formed with the resulting emulsion. The gelatin deriv. is modified gelatin (e.g. acylated gelatin) obtd. by modifying amino groups, imino groups, hydroxyl groups or carbonyl groups as functional groups contained in gelatin with a reagent having a group capable of reacting with the functional groups. Modified gelatin obtd. by substitution for >=50% of amino groups in the molecule of gelatin is preferably used as the gelatin deriv.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a silver halide photographic light-sensitive material that has high sensitivity, low fog, and is resistant to high-temperature rapid processing. This invention relates to silver oxide photographic materials.

[Background of the invention]

In recent years, demands have become increasingly complex and diverse regarding the performance of silver halide photographic materials, and in particular, silver halide photographic materials with stable photographic performance and high to ultra-high sensitivity are required. .

In particular, in the case of X-ray photosensitive materials, the exposure of the human body to X-rays is
In order to reduce the amount of X-rays, there is a demand for photographic materials that have high sensitivity so that more information can be obtained with a smaller amount of X-rays, less fogging, and high image quality.

Methods of increasing the photosensitivity of silver halide photographic materials (hereinafter also simply referred to as light-sensitive materials) include increasing the grain size of silver halide contained in the emulsion layer, and spectral sensitization using sensitizing dyes. This is the most common practice.

It is well known that increasing the grain size of silver halide grains increases sensitivity, but photosensitive materials using silver halide emulsions with large grain sizes generally suffer from increased fog during storage.
There is a tendency for so-called desensitization and poor storage stability.

Many techniques have been disclosed for improving the storage stability of silver halide photographic materials, such as the addition of various additives, but many of them are accompanied by undesirable side effects such as desensitization. At present, the storage stability of high-sensitivity light-sensitive materials containing silver halide grains is still unsatisfactory. In addition, as the grain size increases, undesirable properties such as a decrease in covering power and an increase in desensitization when the photosensitive material is subjected to mechanical pressure such as bending also increase, so it is necessary to increase the size of the silver halide grains. There was a limit to how much sensitivity could be increased.

There are a wide variety of techniques for increasing sensitivity with the same particle size, that is, sensitization methods. For example, there are methods of adding development accelerators such as thioethers to emulsions, methods of supersensitizing spectrally sensitized silver halide emulsions using a suitable combination of dyes, and techniques for improving chemical sensitizers. Although many reports have been made, these methods cannot necessarily be said to be versatile in producing high-sensitivity silver halide photographic materials.

Silver halide emulsions used in high-sensitivity silver halide photographic light-sensitive materials must be chemically sensitized to the maximum extent possible. There is.

On the other hand, spectral sensitization is also an extremely useful means of sensitization, and in the field of medical X-ray photography, from the conventional regular type, which had a sensitive wavelength range of 450 nm, to 54
Orthotype photosensitive materials that are sensitive to a wavelength range of 0.550 nm have come into use. These sensitized products have a wider wavelength range and higher sensitivity, and therefore can reduce the amount of X-rays that they are exposed to and lessen the impact on the human body, but on the other hand, the type of emulsion used If the selection of the dye, the amount used, the combination with other additives, etc., are not appropriate, the sensitization may be impaired or the storage stability of the resulting photosensitive material may be reduced, resulting in insufficient effects. It is often not possible. In particular, high-sensitivity photosensitive materials using large particles tend to exhibit the above-mentioned drawbacks strongly, and there remains much room for improvement.

[Purpose of the invention]

As mentioned above, all the methods of increasing the sensitivity of light-sensitive materials according to the prior art have been hampered by the problem of deterioration in storage stability, and it has been difficult to exceed a certain limit.

The present invention aims to overcome these obstacles and provide a high-sensitivity silver halide photographic material that exhibits extremely little deterioration of photographic properties during storage and has excellent suitability for rapid high-temperature processing.

[Structure of the invention]

As a result of various studies, the inventors of the present invention have solved the above problems by using a silver halide photographic light-sensitive material obtained by agglomerating a silver halide emulsion after chemical ripening with a gelatin derivative and removing dissolved substances in the suspension medium. It has been found that a high-sensitivity silver halide photographic material with improved storage stability and excellent high-temperature rapid processing properties can be obtained.

Generally, in the manufacturing process of photographic silver halide emulsions, a desalting process is usually performed to remove excess halides, nitrates, ammonia, etc. from the silver halide emulsions that have undergone physical ripening. .

Known desalting methods include, for example, the noodle method, dialysis method, and coagulation-sedimentation method, among which the coagulation-sedimentation method is superior to other methods and has been widely put into practical use.

However, these are all desalination steps performed after crystal growth of silver halide grains, and are means for making the subsequent chemical ripening more effective.

The present invention is characterized in that the silver halide emulsion, which has undergone a desalting step after crystal growth and has been subjected to sufficient chemical ripening with a chemical sensitizer, is coagulated again using a gelatin derivative. It is.

The gelatin derivatives used in the present invention are modified by treating an amino group, imino group, hydroxyl group, or carbonyl group as a functional group contained in the gelatin molecule with a reagent having one group capable of reacting with them. It refers to so-called gelatin derivatives such as acylated gelatin, and is also called denatured gelatin or chemically modified gelatin.

The gelatin derivative used in the present invention is preferably modified gelatin in which 50% or more of the amino groups in the gelatin molecule are substituted.

Examples of substituents for amine groups in gelatin are described in, for example, US Pat. No. 2,489.341, US Pat. No. 2,691.582, US Pat.

Substituents useful in the present invention include (1) acyl groups such as alkylacyl, arylacyl, acetyl, and substituted or unsubstituted benzoyl; (2) carbamoyl groups such as alkylcarbamoyl and arylcarbamoyl; (3) alkylsulfonyl; Sulfonyl group such as arylsulfonyl, (4) thiocarbamoyl group such as alkylthiocarbamoyl, arylthiocarbamoyl, (5) carbon number 1-
(6) aryl groups such as substituted or unsubstituted phenyl, naphthyl, and aromatic heterocycles such as pyridyl and furyl;

Particularly preferred modified gelatin has an acyl group (-100OR') carbamoyl. The above R' is a substitution. It is an unsubstituted aliphatic group (for example, an alkyl group having 1 to 18 carbon atoms, an allyl group), an aryl group or an aralkyl group (for example, a phenethyl group), and R2 is a hydrogen atom. Aliphatic group, aryl group.

It is an aralkyl group.

Particularly preferred is the case where R1 is an aryl group and R: is a hydrogen atom.

Specific examples of gelatin derivatives are illustrated below with amino group substituents, but the present invention is limited thereto: Exemplary gelatin derivatives (amine group substituents) The amount of these gelatin derivatives used for desalting is particularly There is no limit, but 0.3 to IO times the amount of gelatin contained as a protective gelatin during desalting (
weight) is suitable, and particularly preferably 1 to 5 times the amount (weight).

The coagulation method using a gelatin derivative after chemical ripening according to the method of the present invention can be carried out in the same manner as the conventional coagulation method after physical ripening.

That is, after adding gelatin derivative, po is adjusted and AgX
Let the emulsion coagulate. The pH for coagulation is 5.
5 or less, particularly preferably 5.0 to 2. The acid used for pH adjustment is not particularly limited, but organic acids such as acetic acid, citric acid, and salicylic acid, and inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid, and phosphoric acid are preferably used. Heavy metal ions such as magnesium ions, cadmium ions, lead ions, zirconium ions, etc. may also be added to the gelatin derivatives.

Desalination may be repeated once or several times. When repeating several times, a gelatin derivative may be added each time desalting is performed, but
It is also possible to simply add the gelatin derivative first.

In the present invention, chemical ripening refers to ripening performed after physical ripening, and although a so-called unfinished thermal emulsion (primitive emulsion) that is not chemically sensitized can be used as the silver halide emulsion, it is usually chemically sensitized. be done.

For chemical sensitization, Glafkidas or Zeli
Kman et al., or edited by H. Frleser, “
Die
Grundlagen derPhotograph
ischen Prozesse with Silbe
rhalogenidenJ, Akade+*1sc
he Verlagsgesellschaft (1
968) can be used.

In other words, sulfur sensitization using sulfur-containing compounds (e.g. thiosulfates, thioureas, mercapto compounds, rhodanines) that can react with active gelatin and silver, reducing substances (
For example, reduction sensitization using stannous salts, amines, hydrazine derivatives, formamidine sulfins, silane compounds), noble metal compounds (for example, gold compounds, and metals from group Ⅰ of the periodic table such as platinum, iridium, palladium, etc.) A noble metal sensitization method using complex salts of 1 to 4 can be carried out alone or in combination.

The silver halide grains contained in the silver halide photographic light-sensitive material of the present invention are silver decogenide containing silver iodide, and are any of silver iodochloride, silver iodobromide, and silver chloroiodobromide. Good too. In particular, in terms of obtaining high sensitivity,
Silver iodobromide is preferred.

The average silver iodide content in such silver halide grains is 0.5 to 10 mol%, preferably 1 to 8 mol%,
Inside the grain, there is a localized portion in which silver iodide is localized at a high concentration of at least 20 mol %.

In this case, it is preferable that the inside of the particle be as far inward as possible from the outer surface of the particle, and in particular 0.00 mm from the outer surface.
It is preferable that the localized portion exists at a distance of 1 μm or more.

Further, the localized portion may exist in a layered manner inside the particle, or may have a so-called core-shell structure, with the entire core serving as the localized portion. In this case, it is preferable that part or all of the core part of the particle excluding the shell part having a thickness of 0.01 μm or more from the outer surface is a localized part with a silver iodide concentration of 20 mol % or more.

In addition, the concentration of silver iodide in the localized portion is 30 to 40
The preferred range is mole %.

The outside of such localized areas is usually coated with silver halide without silver iodide.

That is, in a preferred embodiment, the distance from the outer surface is 0.0
The shell portion with a thickness of 1 .mu.m or more, in particular 0.01 to 1.5 .mu.m, is made of silver iodide-free silver genide (usually silver bromide).

In the present invention, from the inside of the particle (preferably from the outer wall of the particle)
．． At least 2
A method for forming a localized portion of silver iodide at a high concentration of 0 mol % or more may be one that does not use seed crystals.

If seed crystals are not used, the reaction liquid phase containing the protected gelatin (
Since there is no silver halide that can serve as growth nuclei in the mother liquor (hereinafter referred to as mother liquor) before the start of ripening, first, silver ions and halide ions containing high concentration iodine ions of at least 20 mol % are supplied to form growth nuclei. let Then, addition and supply are continued to grow particles from the growth nuclei. Finally, a shell layer having a thickness of 0.01 μm or more is formed from silver halide containing no silver iodide.

If seed crystals are used, at least 20 mol% of the seed crystals alone
The above silver iodide may be formed and then covered with a shell layer. Alternatively, the amount of silver iodide in the seed crystal is O or within the range of 10 mol% or less, and at least 20 mol% of silver iodide is formed inside the grain in the step of growing the seed crystal,
This may be followed by coating with a shell layer.

In the silver halide photographic light-sensitive material according to the present invention, at least 50% of the silver halide grains present in the emulsion layer are
% of grains having localized silver iodide portions as described above.

A preferred embodiment of the silver halide photographic light-sensitive material of the present invention uses silver halide grains having a regular structure or morphology and having localized silver iodide portions as described above.

The term "silver halide grains with a regular structure or morphology" as used herein means grains that grow isotropically without including anisotropic growth such as twin planes, such as cubic, tetradecahedral, octahedral, It has a shape such as a spherical shape.

A method for producing such regular silver halide grains is known, for example, as described in J. Phot, Sci., 5, 332 (1
961), Ber.

Bunsenges, Phys, Chem, 67, 94
9 (1963) + Int-ern.

Congress Photo, Sei, Tokyo (
1967) and others.

Such regular silver halide grains can be obtained by adjusting the reaction conditions when growing silver halide grains using a simultaneous mixing method. In such a simultaneous mixing method, silver halide grains are produced by adding approximately equal amounts of a silver nitrate solution and a silver halide solution to an aqueous solution of a protective colloid while stirring vigorously.

The supply of silver ions and halide ions is necessary and sufficient for the growth of only existing grains, without dissolving the existing crystal grains as the crystal grains grow, and conversely not allowing the generation and growth of new grains. It is preferable to increase the growth rate continuously or stepwise within the critical growth rate for supplying silver halide or within its permissible range. As for this increasing method, Japanese Patent Publications No. 48-36890 and No. 52-163
No. 64 and Japanese Patent Application Laid-Open No. 5-142329.

This critical growth rate is determined by the temperature H, pAg, degree of stirring,
Composition, solubility, particle size, interparticle distance of silver halide grains,
Although it varies depending on crystal habit, type of protective colloid, temperature, etc., it can be easily determined experimentally by methods such as microscopic observation of emulsion particles suspended in a liquid phase and turbidity measurement.

In a preferred embodiment of the present invention, it is desirable that at least 50% by weight of the silver halide grains contained in the silver halide emulsion layer be regular grains as described above.

Another preferred embodiment of the present invention is to use a monodisperse emulsion having a localized silver iodide portion as described above.

The monodisperse emulsion referred to herein means, for example, The
Photographic Journal, 79
．． Trivelli in 330-338 (1939),
At least 95% of the particles, by number or weight, are within ±40% of the mean particle diameter, preferably ±30%, when the mean particle diameter is measured by the method reported by Sm1th.
A silver halide emulsion that is within the range of

Such monodisperse emulsion grains are made using simultaneous mixing techniques, similar to ordered silver halide grains. The conditions for simultaneous mixing are the same as those for producing regular silver halide grains.

Methods for producing such monodispersed emulsions are known, for example, J. Ph.
ot, Sic, 12.242-251 (1963
) JP-A-48-36890, JP-A No. 52-16364,
JP-A-55-142329, JP-A-58-49938
It is stated in each publication of the issue.

In order to obtain the above-mentioned monodispersed emulsion, it is particularly preferable to use seed crystals and to supply silver ions and halide ions using the seed crystals as growth nuclei to grow grains.

The broader the particle size distribution of this seed crystal, the wider the particle size distribution of the particle growth nuclei. Therefore, in order to obtain a monodisperse emulsion, it is preferable to use seed crystals with a narrow particle size distribution at the seed crystal stage.

The above silver halide grains used in the silver halide photographic material of the present invention are described, for example, in "The Theory of the Photo" by T. H. James.
graphic Process I+ 4th edition, Macm
Neutral method, acidic method, ammonia method, forward mixing, back mixing, double jet method, Chondral double jet method, conversion method, core/ It can be manufactured by applying a method such as a shell method.

These silver halide grains or silver halide emulsions containing the grains may also contain various heavy metal salts such as iridium salts and rhodium salts to improve their photographic properties.

Furthermore, during the growth process of these silver halide grains, the outer surface of the grains is improved by temporarily placing the pAg of the mother liquor containing the protective colloid in a state of excess bromine ions of at least 10.5, particularly preferably 11.5 or more. of (Il
l) The effects of the present invention can be further enhanced by rounding the particles by increasing the surface area by 5% or more.

In this case, the increase rate of the (111) plane is relative to that before passing through the above-mentioned 1000 or more phg atmosphere, and especially the increase rate of the (111) plane is 10% or more, more preferably 10 to 20%. It is preferable that

The outer surface of the silver halide grain is the (Ill) plane or the (10
0) How to measure whether one of the surfaces is covered or the ratio thereof can be found in the report by Akira Hirata, “
Butylene of the Society of Santific
Letin of the 5ociety ofSc
ientific Photography of J
apan) No., pages 13.5-15 (1963)
It is described in.

In the present invention, by once passing through an atmosphere in which the pAg of the mother liquor containing protective colloid is at least 1000 or more during grain growth before chemical sensitization, the (Ill) plane increases by 5% or more according to Hirata's measurement method. You can easily check whether this is the case.

In this case, the above-mentioned 9Ag is applied before chemical sensitization, but preferably from the time when silver ions are added for the growth of silver halide grains to before the desalting process, especially after the addition of silver ions is completed. Therefore, it is preferable to carry out the so-called desalting step which is usually carried out before chemical sensitization. This is because it is easy to obtain a monodispersed emulsion with a narrow particle size distribution.

In addition, aging in an atmosphere where 9Ag is 1000 or more,
It is preferable to do this for 2 minutes or more.

By controlling pAg in this manner, the number of (111) planes increases by 5% or more, resulting in a rounded shape.

When the average grain size of the silver halide grains used in the present invention is larger than 3.0 .mu.--, the graininess deteriorates significantly, and the sensitizing effect cannot necessarily be obtained, making it impossible to achieve the object of the present invention. On the other hand, when the average particle size is smaller than 0.2 μl, the sensitivity decreases significantly, making it impossible to obtain the desired sensitivity and aqueous curve. The average grain size of the silver halide grains in the present invention is preferably in the range of 0.4 to 1.7 microns.

The silver halide emulsion of the present invention is prepared at a pA suitable for chemical sensitization by an appropriate method after the growth of silver halide grains of /% is completed.
g or ion concentration. For example, the flocculation method and the noodle washing method, Research Disclosure 1764
No. 3 (Research Disclosure 17)
No. 643).

Further, in the present invention, an emulsion may be used alone,
Two or more types of silver halide emulsions having different average grain sizes may be used in combination.

In this case, the silver halide composition of each emulsion may be different or the same.

Chemical sensitization methods applied to silver halide grains as described above include, for example, sulfur sensitization methods using sodium thiosulfate, thiourea compounds, etc., gold sensitization methods using chlorauric acid salts, gold trichloride, etc. There are reduction sensitization methods using thiourea dioxide, stannous chloride, silver ripening, etc., palladium sensitization methods, selenium sensitization methods, etc., and these methods can be used alone or in combination of two or more. Can be done. In this case, it is particularly preferable to use gold sensitization and sulfur sensitization together.

In addition to the above-mentioned sulfur sensitization method, selenium sensitization method can also be used for the silver halide emulsion used in the present invention. For example, U.S. Pat.
The method described in Japanese Patent Publication No. 44-15748 can be used.

When a mixture of two or more emulsions is used, the emulsions may be mixed and chemically sensitized, or each emulsion may be chemically sensitized individually and then mixed.

The silver halide grains of the present invention have I
Noble metal ions such as r, Rh, Pt, and Au can be added and included inside the particles, and also have a low pA
A reduction sensitizing liquid can be applied inside the particles using a g atmosphere or a suitable reducing agent.

In the silver halide photographic material of the present invention, the emulsion can be subjected to spectral sensitization. There are no particular limitations on the spectral sensitizer, and for example, known spectral sensitizers commonly used for spectral sensitization of silver halide emulsions, such as cyanine dyes and merocyanine dyes, can be used.

Gelatin is the most preferred hydrophilic colloid for dispersing the silver halide grains used in the present invention, but in order to further improve the physical properties of the binder, cellulose derivatives such as cellulose ether, partially hydrolyzed cellulose acetate, carboxylic Methyl cellulose, etc., or synthetic hydrophilic resins such as polyvinyl alcohol, polyvinylpyrrolidone, acrylic and methacrylic acids or their derivatives, such as homo- and copolymers of esters, amides and nitriles, vinyl polymers such as vinyl ethers and vinyl esters can be used.

During rapid processing using an automatic processor, it is desirable that the amount of gelatin in the silver halide photographic material be as small as possible in order to improve drying properties. On the other hand, when the amount of gelatin decreases, its protective colloidal properties decrease, making pressure marks more likely to occur during roller conveyance. Therefore, the amount of gelatin used in the silver halide photographic material according to the present invention is as follows:
For the weight of the amount of silver in the silver halide used,
The weight ratio (gelatin amount/silver amount) is preferably 0.4 to 0.8.

The silver halide emulsion used in the silver halide photographic light-sensitive material according to the present invention may be used as a stabilizer and a capri inhibitor, for example, as disclosed in U.S. Pat.
No. 62, same No. 3. -512.982, same number 3,342
．． 596, German Patent No. 1,189.380, German Patent No. 2
Specifications of No. 05.862, fi'il No. 211.841, Japanese Patent Publication No. 43-4183, No. 39-2825,
Methods using stabilizers and fog suppressants described in JP-A-50-22626 and JP-A-50-25218 may be applied, and particularly preferred compounds include 4-hydroxy-6-methyl- 1,3,3a,7-chitrazaindene, 5,6-drimethylene-7-hydroxy-s-
) RiazoC1(1,5,-a)pyrimidine, 5,6-titramethylene-7-hydroxy-s-triazolo(1°5-a)pyrimidine, 5-methyl-7-hydroxy-S
- triazolo(1,5-a) pyrimidine, 7-hydroxy-5-)j77 solo(1,5-a) pyrimidine, gallic acid esters (e.g. isoamyl gallate, dodecyl gallate, propyl gallate, sodium gallate, etc.) )
, mercaptans (e.g. l-7enyl-5-mercaptotetrazole, 2-mercaptobenzthiazole, etc.), benztriazoles (e.g. 5-bromobenztriazole, 4-methylbenztriazole, etc.), benzimidazoles (e.g. 6-nidrobenztriazole, etc.) (penzimidazole, etc.).

The silver halide light-sensitive material according to the present invention may contain a photographic hardening agent commonly used in its coating solution, such as an aldehyde-based hardener or an aziridine-based hardener (for example, PR Report, 19.92L U.S. Pat. No. 2,950.197, No. 2.964,404, No. 2.983.611, No. 3.271.175
Specifications of each issue, Japanese Patent Publication No. 46-40898, Japanese Patent Publication No. 1973
-91315), inoxazole systems (e.g. those described in U.S. Pat. No. 331.609), epoxy systems (e.g. U.S. Pat. No. 3.047),
．． No. 394, specifications of West German Patent No. 1.085.663, British Patent No. 1.033.518, Japanese Patent Publication No. 1973-3
5495), vinyl sulfone type (
For example, PB Report 19,920, West German Patent No. 1.10
0.942, British Patent No. 1,251.091, Japanese Patent Application Publication No. 45-54236, Japanese Patent Application Publication No. 48-110996, and United States Patent No. 353.964, Japanese Patent Publication No. 3.490.911. ), acryloyl-based (e.g. Japanese Patent Application No. 48-27949, U.S. Patent No. 3.640.720)
No. 2,938,892), carbodiimides (e.g., U.S. Pat. No. 2,938,892, Japanese Patent Publication No.
-38715, Japanese Patent Application No. 49-15095), other maleimide-based, acetylene-based,
Hardening agents such as methanesulfonic acid ester type, triazine type, and polymer type can be used. In addition, as a thickening agent, for example, US Patent No. 3.167.410, Belgian Patent No. 5
58.143, polyols as gelatin plasticizers (for example, U.S. Pat. No. 2,960,
Specification No. 404, Japanese Patent Publication No. 43-4939, Japanese Patent Publication No. 48
-63716), and as latexes, the specifications of U.S. Patent No. 766.979, French Patent No. 1.395.554, and Japanese Patent Publication No. 48-43
125, and as a matting agent, those described in British Patent No. 1.221.980 can be used.

Desired coating aids can be used in the constituent layers of the silver halide photographic material according to the present invention, such as saponin or sulfosuccinic acid surfactants, such as those described in British Patent No. 548,532, esp. Gansho 47-89630
or as anionic surfactants, for example, Japanese Patent Publication No. 43-18166,
U.S. Patent No. 3,514.293, French Patent No. 2.
Specifications of No. 025.688, Japanese Patent Publication No. 43-10247
Those described in the No. 1 publication can be used.

In the silver halide photographic material according to the present invention, a dye can be used in the layer below the emulsion layer of the present invention that is in contact with the support in order to reduce the so-called crossover effect, and also to reduce the sharpness of the image. Dyes can be added to the protective layer and/or the emulsion layer of the present invention to improve or reduce fog caused by safe light. As such a dye, any known dye for the above purpose can be used.

In addition, in order to apply the emulsion of the present invention to a color photosensitive material, the emulsion of the present invention adjusted to have red sensitivity, green sensitivity, and blue sensitivity is combined with cyan, magenta, and yellow couplers to be contained in the color photosensitive material. The methods and materials used should be appropriate.

Useful couplers include closed methylene yellow couplers, pyrazolone magenta couplers, and phenolic or 7-tole cyan couplers.These couplers can be combined with colored couplers for automasking (e.g., with a bonding group at the active site of the coupler). couplers with a split-off group bonded with an azo group), osazone-type compounds, development-diffusive dye-releasing couplers, and development inhibitor-releasing compounds (which inhibit development by reacting with the oxidized form of an aromatic primary amine developing agent). is a compound that releases a type compound,
(includes both so-called DIR couplers, which react with oxidized forms of aromatic primary amine developing agents to form colored dyes, as well as so-called DIR substances, which form colorless compounds)
It is also possible to use In order to incorporate these couplers into a silver 10ogenide color photographic light-sensitive material, various known techniques conventionally used for couplers can be applied.

The silver halide photographic material of the present invention can be obtained by coating the above-mentioned emulsion on a support.

In the silver halide photographic material according to the present invention, when two or more types of silver halide emulsions having different average grain sizes are used, they can be individually decomposed into films and coated on the support. , or can be mixed and applied.

The support used in the silver halide photographic emulsion of the present invention is
It includes all known materials, such as polyester films such as polyethylene terephthalate, polyamide films, polycarbonate films, styrene films, baryta paper, and papers coated with synthetic polymers. The emulsion of the present invention can be coated on one or both sides of the support, and when coated on both sides, the emulsion can be applied symmetrically or asymmetrically with respect to the support.

Although the present invention is applicable to all silver halide photographic materials, it is particularly suitable for high-sensitivity black-and-white or color negative photographic materials. When applied to medical X-ray radiography, for example, a fluorescent intensifying screen whose main component is a phosphor that emits near-ultraviolet to visible light upon exposure to penetrating radiation is coated on both sides with the emulsion of the present invention. It is desirable that both surfaces of the silver halide material according to the present invention are exposed to light. The penetrating radiation herein refers to high-energy electromagnetic waves, and means X-rays and γ-rays. And here, the fluorescent intensifying screen refers to, for example, an intensifying screen whose main fluorescent component is calcium tungstate (CaWO4),
It is a fluorescent intensifying screen whose main fluorescent component is a rare earth compound activated with terbium.

The silver halide photographic material according to the present invention can be developed by a commonly used known method. The black and white developer is a commonly used developer such as hydroquinone, l-phenyl-3-pyrazolidone, N-methyl-p-
Those containing aminophenol or p-7 22-diamine alone or in combination of two or more thereof are used, and other commonly used additives can be used.

Further, when the light-sensitive material is for color use, color development can be carried out by a commonly used color development method.

Developers containing aldehyde hardeners can also be used in the silver halide photosensitive material of the present invention, such as dialdehydes such as maleic dialdehyde, glutaraldehyde and their sodium bisulfite salts, etc. Developers known in the photographic field may also be used.

Hereinafter, the present invention will be illustrated by examples, but the embodiments of the present invention are not limited by these examples.

〔Example〕

Example 1 (A) Iodide containing 2 mol% of silver iodide with an average grain size of 0.3 μm was prepared by the double jet method while controlling the seed crystal preparation temperature at 60'O% pAg = 8 and pH -2.0. Monodisperse cubic grains of silver bromide were prepared, and then desalted as shown below to obtain seed crystals of silver iodobromide.

(Desalting method) Add 1 aldehyde resin of sodium naphthalene sulfonate per mole of silver halide to the silver iodobromide solution after mixing.
5 g and 60 g of magnesium sulfate were each made into aqueous solutions and added at 40°C. After stirring for 3 minutes, the mixture was allowed to stand and excess salts were removed by decantation. Next, 40° C. pure water was added to disperse 2.1 ρ per mole of silver halide, and then 30 g of magnesium sulfate was added, stirred for 3 minutes, allowed to stand, and decanted again. Thereafter, gelatin was added and the mixture was kept at 550C and stirred for 20 minutes to redisperse the mixture to obtain seed crystals.

(B) Growth from seed crystals Particle growth was performed using the seed crystals obtained in (A) above. First, seed crystals were dissolved in 8.5a of a protected gelatin solution (containing ammonia if necessary) kept at 4000, and the po was adjusted with acetic acid.

A 3.2N aqueous ammoniacal silver ion solution was added to this mother liquor by a double jet method.

In this case, the pH and EAg were changed as needed depending on the silver iodide content and crystal habit.

That is, the pAg was controlled to 7.3 and the pH to 9.7 to form a layer having a silver iodide content of 35 mol %.

Next, pu was changed to 8 to 9, and pAg was kept at 7.0 to grow particles.

Then, a potassium bromide solution was added through a nozzle over 8 minutes, and the pA
g was reduced to 11.0, and mixing was completed 3 minutes after addition of the potassium bromide solution. The pH was then lowered to 6.0 with acetic acid. The obtained emulsion was monodisperse grains having an average grain size of 0.53 μm and a silver iodide content of 2 mol % in the entire grains.

Next, a method for desalting this emulsion will be described.

(Desalting method) After mixing, add the same solution as above to the reaction solution at 40°C.
5.5 g of aldehyde resin of sodium salt of talenesulfonic acid and 8.5 g of magnesium sulfate per mole of silver halide.
After adding g and stirring for 3 minutes, the mixture was allowed to stand and decanted.

Then, after adding 1.812% of pure water at 40℃ and dispersing it,
20 g of magnesium sulfate was added, stirred for 3 minutes, allowed to stand, and then decanted.

This process using pure water and ffLs magnesium was repeated again to remove excess salts.

Next, add an aqueous solution containing 15 g of gelatin to bring the total amount to 450.
After finishing the mixture to 55° C. and 20 minutes, an emulsion was obtained.

The emulsion thus obtained was treated with a flocculant, that is, a gelatin derivative, after chemical sensitization according to the method of the present invention, as follows.

Chemical sensitization is carried out by adding appropriate amounts of ammonium thiocyanate, chloroauric acid and sodium thiosulfate, and after chemical ripening, 4-hydroxy-6-methyl-1,3,3a,7-titrazaindene is added as a ripening stopper. Added appropriate amount.

Then, 15 (l) of potassium iodide was added per mole of silver halide.
ag and the following spectral sensitizing dyes DYe -1 and DYe -2
300 mg and 15 g of each were added to obtain an ortho emulsion.

DYe-1 DYe-2 The obtained emulsion was divided into eight parts, one of which was used as a comparison sample, and the other seven were each added with the compounds according to the present invention as shown in Table 1 at 40°C. After stirring for 3 minutes, the pH was adjusted to 4.0 with caustic potassium and the mixture was allowed to stand, followed by decantation. Next, add 40°C pure water at 2.1Q per mole of silver halide, and then adjust the pH to 5 with caustic potassium.
．． Turn to 8 and stir for 5 minutes. Thereafter, the pH was lowered to 4.3 with a 1.7 N nitric acid aqueous solution, and the mixture was allowed to stand and decanted.

Then add the gelatin solution and adjust the pH to 5.
8 and redispersed.

To each of the eight types of high-sensitivity silver iodobromide emulsions obtained were added a copolymer of styrene and maleic anhydride as a thickener, and appropriate amounts of trimethylolpropane and diethylene glycol as wetting agents.

Then, an appropriate amount of radium-isoamyl-N-decyl-sulfosuccinate as a coating aid and an appropriate amount of formalin as a hardening agent were added, and the mixture was uniformly coated onto a polyethylene terephthalate support so that the amount of silver was 3 g/m''.

The obtained sample was placed in a constant temperature room at 23°C for 3 days as a storage test.
Two samples were prepared: one that had been left for one day, one that had been left in a constant temperature room at 50°C for three days, and another untreated fresh sample.

These samples were exposed using a KS-1ffi centometer [manufactured by Konica Corporation] based on the JiS method, and then exposed using a KX-50 centometer.
0 Automatic developing machine [manufactured by Konica Corporation] to perform development for 350,030 seconds using XD-90 developer.

The results of sensitometry of the sample after fixing, washing with water and drying are shown in Table 1 below.

Note that the sensitivity in the table is for sample 1 (comparison). On the other hand, it can be seen that the film maintains excellent photographic characteristics with less increase in fog and less deterioration in sensitivity during storage.

Example 2 Two emulsions shown in Table 2 below were treated in exactly the same manner as the emulsion obtained in Example 1, and an emulsion for comparison was prepared.

Table-2 4 each of (A), (B) and (C) emulsions of the above batter-2
Coating solutions were prepared in the same manner as in Example 1, except that a known fog suppressant was added to a total of 12 different emulsions as shown in Table 3 below.

Next, two layers were simultaneously coated on both sides of the subbed polyethylene terephthalate support, including a protective layer, so that the amount of coated silver was 5 gems on both sides, and then dried to produce a high-sensitivity X-ray silver halide film. .

The coating solution for the protective layer was a 3% aqueous gelatin solution, and the coating aid and hardening agent contained appropriate amounts of the same ones used in Example-1, and the amount of gelatin coated on both sides was 6.5 g/ m”
It was coated so that it would look like this.

The obtained film was subjected to the same storage test as in Example 1 and then developed, and the sensitometric results are shown in Table 3.

However, the sensitivities in the table are relative sensitivities expressed with fresh pieces of sample No. 9, which is a comparative sample, as 100.
As can be seen from Sample No. 3, Comparative Emulsion (C) Sample No. 3 does not undergo coagulation and water washing after chemical ripening by the conventional method by adding a typical Capri inhibitor.

Sample Nos. 17 to 20 have a slight capri suppression effect and cause desensitization, whereas sample Nos. of emulsions (A) and CB) according to the present invention were subjected to coagulation and water washing after chemical ripening.

In Nos. 9 to 16, the capri suppressing effect with less desensitization was further emphasized by the addition of a capri inhibitor, and silver halide photographic materials having stable photographic properties were obtained.

〔Effect of the invention〕

As explained in detail in the examples above, the present invention makes it possible to provide a silver halide photographic material which has high sensitivity, little generation of capri during storage, and stable performance.

Claims (1)

[Claims] In a photographic light-sensitive material having at least one photosensitive silver halide emulsion layer on a support, at least one of the silver halide emulsion layers is a silver halide coagulated with a gelatin derivative after chemical ripening. A silver halide photographic material characterized by being an emulsion.