JPH07114131A - Silver halide photographic emulsion, silver halide photographic sensitive material for medical use, and processing method therefor - Google Patents

Abstract

PURPOSE:To obtain high sensitivity with little residual colors, to obtain low sensitivity for red safe light, and to improve storage property with time by adding specified several spectral sensitizing dyes and specified silver halide. CONSTITUTION:Spectral sensitizing dyes expressed by formulae I and II are added to the emulsion as at least one of these dyes in a solid fine particle state. The emulsion contains such silver halide that has featuring J-band in 520-560nm range when the reflection spectra is measured and >=50% of the starting point for development is a peak and/or near the peak. In formula I, R1, R3 are alkyl groups, R2, R4 are lower alkyl groups, V1-V4 are hydrogen atoms or substituents in which the total sum of Hammett values sigmap is <1.7, and n is 1 or 2. In formula II, R5 and R6 are alkyl groups or the like, R7 is a hydrogen atom or the like, and Z1, Z2 are nonmetal atom groups necessary to complete benzene rings. X1, X2 in formulae I, II are ions necessary to neutralize charges in the molecules.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silver halide photographic emulsion capable of providing a silver halide photographic light-sensitive material having high sensitivity, low dye contamination, low sensitivity to red safelight, and excellent storage stability. In particular, the present invention relates to a silver halide photographic emulsion capable of providing a light-sensitive material which can be applied to an advantageous processing method in the field of X-ray medical silver halide photographic light-sensitive material.

[0002]

BACKGROUND OF THE INVENTION In recent years, for example, in the medical field, the number of examinations including regular medical examinations, widespread use of medical checkups, and examinations in general medical care has rapidly increased. The demand for ultra-high-speed processing and reduction of processing waste liquid is increasing more and more.However, if the processing time of each processing step is shortened, the sensitivity of the conventional photosensitive material is lowered, the gradation is deteriorated, and the image quality is deteriorated due to defective fixing. Image quality is deteriorated due to residual dye (residual color). Therefore, in order to solve such a problem, it is necessary to accelerate the developing speed or the fixing speed, to reduce the amount of dye, and to promote the desorption and / or decolorization of the dye. On the other hand, if a means for reducing the development processing waste liquid is taken, there is a common problem with the above-mentioned speeding up.

As a technique for improving the above problems, EP0506584
The specification, JP-A-5-88293 and JP-A-5-93975 disclose techniques using benzimidazolocarboxycyanines having good decolorizing performance as spectral sensitizing dyes. Further, in JP-A-5-61148, the iodine content is 1
An oxacarbocyanine compound and a benzimidazolocarboxycyanine compound were used together as a spectral sensitizer at a specific ratio in a mol% or less silver halide emulsion, and a selenium compound and / or
Alternatively, a technique of chemically sensitizing with a tellurium compound is disclosed.

On the other hand, as a technique for speeding up development,
A technique for limiting the formation position of the development start point to a specific position is disclosed in JP-A-63-305343.

However, although these have improved residual color or rapid development, they have a drawback that the sensitivity is not sufficient and the sensitivity is greatly reduced when stored under high humidity and high temperature. .

Further, the sensitivity to red safelight which is intended to be highly sensitive by changing the combination ratio of oxacarbocyanines and benzimidazolocarboxycyanines described in the above-mentioned JP-A-5-61148 becomes high. Therefore, there were practical restrictions.

By the way, in recent years, many studies have been conducted on techniques for improving the sensitivity and improving the image quality using tabular silver halide grains. These tabular silver halide grains are so-called normal crystal halogenated grains such as hexahedron and octahedron. Compared with silver particles,
Since the surface area is large in the same volume, it is possible to increase the adsorption amount of the sensitizing dye on the particle surface, and as a result, it is considered that there is an advantage that the sensitivity can be improved and the sharpness can be improved by reducing the scattered light. ing.

However, in practice, even if the amount of the sensitizing dye is increased in accordance with the surface area of the tabular grains, the sensitivity is not as high as expected, and as a drawback, as the development processing is accelerated, Contamination due to residual dye, image quality deterioration, etc. have become apparent as problems.

[0009]

SUMMARY OF THE INVENTION Therefore, the first object of the present invention is to provide a silver halide photographic light-sensitive material having high sensitivity, little residual color, low sensitivity to red safelight, and excellent storage stability over time. It is to be.

A second object of the present invention is to have the above performance,
Another object of the present invention is to provide a medical silver halide photographic light-sensitive material applicable to an advantageous processing method. Other purposes will become apparent from the following.

[0011]

The above object of the present invention is to provide a spectral sensitizing dye represented by the general formula (I) [Chemical formula 1] and the general formula (I)
I) the spectral sensitizing dye represented by [Chemical Formula 2], at least one of which is added as solid fine particles, and a J-band characteristic at 520 to 560 nm is formed when the reflection spectrum is measured. A silver halide photographic emulsion containing silver halide having 50% or more of the development starting point at and / or near the apex, and 70% or more of the total projected area of silver halide grains contained in the emulsion has an aspect ratio. Two or more tabular silver halide grains, the silver halide grains in the emulsion being chemically sensitized in the presence of a selenium and / or tellurium compound, and containing the silver halide photographic emulsion A silver halide photographic light-sensitive material for medical use, which is developed with a developer containing substantially no hardener, and the total processing time is 15 seconds to 90 seconds.
Second, the processing method of the silver halide photographic light-sensitive material for medical use according to the second aspect is achieved.

The present invention is described in detail below.

The above-mentioned spectral sensitizing dye in the present invention refers to one that contributes to the sensitization of silver halide grains, and does not include an organic dye that functions as a filter.

Examples of R ₁ and R _{3 in} the general formula (I) include hydroxymethyl, ethoxycarbonylethyl, ethoxycarbonylmethyl, allyl, benzyl, phenethyl, methoxyethyl, methanesulfonylaminoethyl,
3-oxobutyl, methyl, ethyl, propyl, butyl and the like can be mentioned, and at least one is preferably a group other than an ethyl group.

R ₂ and R ₄ are, for example, methyl, ethyl, butyl, trifluoroethyl, carboxymethyl,
Carboxyethyl, methanesulfonylaminoethyl, sulfobutyl, sulfoethyl, sulfopropyl, sulfopentyl, 6-sulfo-3-oxahexyl, 4-sulfo-3-oxapentyl, 10-sulfo-3,6-dioxadecyl, 6-sulfo
Examples include groups such as -3-thiahexyl, o-sulfobenzyl, p-carboxybenzyl and the like.

Examples of V ₁ , V ₂ , V ₃ and V ₄ include a halogen atom, an alkyl group, an alkoxy group, an alkylthio group, a trifluoromethyl group, a cyano group, a carboxy group,
Alkoxycarbonyl group, acyl group, sulfonyl group, carbamoyl group, sulfamoyl group, acetylamino group,
Examples include groups such as acetyloxy group.

X ₁ may be either an anion or a cation, and the anion is, for example, a halogen ion,
There are perchlorate, ethyl sulfate, thiocyanate, p-toluene sulfonate, perfluoroborate and the like, and examples of the cation include hydrogen ion, alkali metal ion, alkaline earth metal ion, ammonium ion, organic ammonium ion and the like.

Preferred among the substituents represented by V ₁ , V ₂ , V ₃ and V ₄ are those having an S value derived from the following [Formula-A].
It is a group that gives a value smaller than 1.0.

S = L / {(B ₁ + B ₂ + B ₃ + B ₄ ) / 2} [Formula-A] In the formula, L, B ₁ , B ₂ , B ₃ and B ₄ represent STERIMOL parameters.

Specifically, methyl (S = 0.815), ethyl (S
= 0.992), t-butyl (S = 0.728), methoxy (S = 0.99)
3), methylthio (S = 0.982), trifluoromethyl (S =
0.697), acetyl (S = 0.893), methanesulfonyl (S =
0.825), carboxy (S = 0.87), carbamoyl (S = 0.
93), groups such as sulfamoyl (S = 0.726), fluorine atoms
(S = 0.981), chlorine atom (S = 0.978), bromine atom (S = 0.9)
82) and the like.

The Hammett σp value is a substituent constant obtained by the Hammett et al. From the electronic effect of the substituent on the hydrolysis of ethyl benzoate, and the STERIMOL parameter is obtained from the projection diagram for the bond axis with the benzene nucleus. It is a value defined by the length, Journal of Organic Chemistry, Vol. 23, 420-427 (1958), Experimental Chemistry Course, Vol. 14 (Maruzen Publishing Co., Ltd.), Physical Organic
Chemistry (Mc Graw Hill Book, 1940), Drag Design Volume VII (Academic Press New York: 1976)
Year)), the structure-activity relationship of drugs (Nankodo: 1979), and the like.

Next, the above-mentioned general formula (I) used in the present invention is used.
Specific examples of the spectral sensitizing dye represented by

[0023]

[Table 1]

[0024]

[Table 2]

As the spectral sensitizing dye represented by the general formula (I) of the present invention, in addition to the above-mentioned specific examples, for example, JP-A-HEI-1
II-3 and II- of the compound examples described in Japanese Patent Publication No. 4-9040
4, II-6, II-7, II-8, II-10, II-13, II-14, II-1
6, II-17, II-18, II-20, II-21, II-24 to II-44 and the like can be similarly used.

The spectral sensitizing dye represented by the above general formula (I) according to the present invention is, for example, British Patent Nos. 521,165 and 745,546.
No., Belgium Patent 615,549, Soviet Patent 412,218
No. 432,166, etc., Japanese Patent Publication No. 38-7828, No. 42
-27165, 42-27166, 43-13823, 43-14497
No., No. 44-2530, No. 45-27676, No. 45-32740, etc., according to the method described in Harmer's cyanine soybean-related compounds (Jhon Wiley & Sons, New York, 1964), etc. Can be synthesized.

Next, in the spectral sensitizing dye represented by the general formula (II) according to the present invention, R ₅ and R ₆ are, for example, methyl, ethyl, propyl, butyl, 2-hydroxyethyl as a hydroxyalkyl group, 4-hydroxybutyl, etc.
2-acetoxyethyl, 3-acetoxybutyl etc. as acetoxyalkyl group, 2-carboxyethyl, 3-carboxypropyl, 2- (2-carboxyethoxy) ethyl etc. as carboxyalkyl group, 2-sulfoethyl, 3-sulfoalkyl group Examples include groups such as sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, 2-hydroxy-3-sulfopropyl, allyl, butynyl, octenyl, oleyl, phenyl and carboxyphenyl, but at least one is a sulfoalkyl group or carboxy. It is an alkyl group.

The ion represented by X ₂ in the general formula (II) is, for example, chlorine ion, bromine ion, iodine ion, thiocyanate ion, sulfate ion, perchlorate ion, p-toluenesulfonate ion, Examples thereof include ethylsulfate ion, sodium ion, potassium ion, magnesium ion and triethylammonium ion.

In R ₇ , the lower alkyl group is
Examples of the aryl group include groups such as methyl, ethyl, propyl and butyl, and examples of the aryl group include phenyl group.

Z ₁ and Z ₂ represent a group of non-metal atoms necessary for completing a substituted or unsubstituted benzene ring. m represents 1 or 2, and when forming an intramolecular salt, m is 1. Next, specific examples of the spectral sensitizing dye represented by the general formula (II) used in the present invention will be given.

[0031]

[Chemical 3]

[0032]

[Chemical 4]

The sensitizing dye represented by the general formula (II) used in the present invention is "Heterocycrlic compoun" by FM Hamer.
ds Cyaninedyes and related compounds ”(Heterocyclic Compounds-Cyanine Dyes and Relayed Compounds) IV.V.VI, Chapter 89-199
Wiley & Sons (New York, London) 1964, or D.
M.S Turmer “Heterocycrlic compounds special topi
cs in Heterocycrlicchemistry ”(Heterocyclic Compounds-Special Topics Inroheterocyclic Chemistry) Chapter VIII IV.482-515 J
It can be easily synthesized based on the method described in Ohn Wiley & Sons (New York, London), 1977, etc.

Both of the above general formulas (I) and (II) show only one state of the resonance structure, and even if it is expressed in the limit state where the + charge enters the symmetrical heterocyclic nitrogen atom. It means the same substance.

The combined use technique of two kinds of spectral sensitizing dyes according to the present invention is useful in a light-sensitive material which requires sensitivity to green light. In particular, it is remarkably effective in the application to an X-ray recording material using a phosphor that emits green light in order to increase the recording sensitivity to X-rays, and is particularly effective in a light-sensitive material for X-ray medical treatment.

In the application to the X-ray medical light-sensitive material using a phosphor emitting green light, the spectral sensitizing dye represented by the general formula (I) and the spectral sensitizing dye represented by the general formula (II) are used. It is preferable to combine them so that they are adsorbed on silver halide emulsion grains and a J-band is formed in the same wavelength range as the green light from the phosphor when the reflection spectrum thereof is measured. That is, J that is usually peculiar to 520 nm to 560 nm region
-It is preferable to select and combine the spectral sensitizing dyes so that a band is formed.

When the long wave end of the J-band extends to the longer wavelength side than 570 nm, the red safelight light is absorbed. Therefore, the J-band having a low light absorption rate in the region of 570 nm or more is set. Is desirable.

The amount of the spectral sensitizing dyes of the general formulas (I) and (II) in the present invention to be added varies depending on the kind of the dye and the structure, composition, ripening condition, purpose, use of the silver halide, The surface coverage of each photosensitive particle in the silver emulsion is preferably 40% or more and 90% or less, more preferably 50% to 80%.

In the present invention, the monolayer coverage is 50.
Saturated adsorption amount when the adsorption isotherm was created at ℃
The amount corresponding to 100% will be decided relatively.

The appropriate amount per mol of silver halide varies depending on the total surface area of silver halide grains in the emulsion, but 60
Less than 0 mg is preferred. Further, it is preferably 450 mg or less.

As a solvent for the sensitizing dye, a conventionally used water-miscible organic solvent can be used.

Surfactants have been conventionally used as dispersants for spectral sensitizing dyes. The surfactant includes anionic, cationic, nonionic and amphoteric surfactants, and any of these surfactants can be used in the invention.

However, in the present invention, the effect is increased by adding the spectral sensitizing dye as a dispersion in the form of solid fine particles, as compared with the case of adding it as a solution of an organic solvent.
In particular, at least one of spectral sensitizing dyes is added in the state of a substantially water-insoluble solid fine particle dispersion dispersed in an aqueous system in which substantially no organic solvent and / or surfactant is present. Is preferred.

A technique for mechanically dispersing an organic dye in an aqueous medium is disclosed in, for example, Japanese Patent Laid-Open No. 3-288842. However, this method is for making the organic dye resistant to diffusion in the photographic light-sensitive material, and is merely a dispersion addition method.

On the other hand, the present invention was made to uniformly and effectively adsorb the photographic photosensitizing dye onto the surface of the silver halide grain, and the above-mentioned technique merely for adding in a dispersed state is , The purpose and effect are different.

In the present invention, substantially organic solvent and / or
Alternatively, the aqueous system in which no surfactant is present is water containing impurities at a level that does not adversely affect the silver halide photographic emulsion, and more preferably ion-exchanged water and distilled water.

The solubility of the spectral sensitizing dye in the present invention in water is 2 × 10 ⁻⁴ to 4 × 10 ⁻² mol / l, more preferably 1 × 10 ⁻³ to 4 × 10 ⁻² mol / l. Is.

When the solubility is lower than this range, the dispersion particle size becomes very large and the dispersion becomes non-uniform, so that a precipitate of the dispersion may be formed after the dispersion is completed, or the dispersion may be added to the silver halide emulsion. Sometimes it interferes with the adsorption process of dyes to silver halide.

On the other hand, when the solubility is higher than the above range, the viscosity of the dispersion is increased more than necessary, air bubbles are entrapped, and the dispersion is hindered. At higher solubility, dispersion becomes impossible. It became clear from the study of the present inventors.

In the present invention, the solubility of the spectral sensitizing dye in water was measured by the following method.

That is, 30 ml of ion-exchanged water was placed in a 50 ml Erlenmeyer flask, and a dye which was not completely dissolved by visual observation was added to it.
The temperature was maintained at 27 ° C in a constant temperature bath, and stirring was performed for 10 minutes with a magnetic stirrer. The suspension was filtered with filter paper No. 2 (manufactured by Toyo [stock]), the filtrate was filtered by a disposable filter (manufactured by Tosoh [stock]), the filtrate was appropriately diluted, and a spectrophotometer U-3410 (Hitachi) was used. (Manufactured by [stock]) was used to measure the absorbance. Next, based on this measurement result, the dissolved concentration was determined according to the Lambert-Beer law, and the solubility was further determined.

D = εlc Here, D is the absorbance, ε is the spectral extinction coefficient, l is the cell length for measuring absorbance, and c is the concentration (mol / l).

The spectral sensitizing dye according to the present invention can be added during the chemical ripening step, particularly preferably at the start of the chemical ripening step, and the desalting can be performed from the nucleation step of the silver halide emulsion according to the present invention. A high-sensitivity silver halide emulsion excellent in spectral sensitization efficiency can be obtained by adding it by the end of the process, and the above-mentioned process can be carried out at any time after the completion of the desalting process, through the chemical ripening process and immediately before the coating process. The spectral sensitizing dye according to the present invention, which is the same as or different from the dye added in the step (from the nucleation step to the end of the desalting step), may be additionally added.

The spectral sensitizing dye of the present invention may be used in combination with other spectral sensitizing dyes. In addition to the spectral sensitizing dye, a dye having no spectral sensitizing property or a substance which does not substantially absorb visible light and exhibits a supersensitizing effect may be added to the emulsion layer.

Examples of the selenium sensitizer used for the chemical sensitization of the present invention include, for example, US Pat. Nos. 1574944 and 1602592.
No. 1623499, JP-A-60-150046, JP-A-4-25832, JP-A-4-109240, and JP-A-4-147250. Useful selenium sensitizers include colloidal selenium metal, isoselenocyanates (eg,
Allyl isoselenocyanate, etc.), selenoureas (eg, N, N-dimethylselenourea, N, N, N′-triethylselenourea, N, N, N′-trimethyl-N′-heptafluoroselenourea, N , N, N'-Trimethyl-N'-heptafluoropropylcarbonylselenourea, N, N, N'-Trimethyl-N'-4
-Nitrophenylcarbonyl selenourea etc.), selenoketones (eg selenoacetone, selenoacetophenone etc.), selenoamides (eg selenoacetamide, N, N-dimethylselenobenzamide etc.), selenocarboxylic acids and selenoesters (eg 2-selenopropionic acid, methyl-3-selenobutylate, etc.), selenophosphates (eg, tri-p-triselenophosphate, etc.), selenides (diethyl selenide, diethyl diselenide, etc.) . Particularly preferred selenium sensitizers are selenoureas, selenoamides, and selenium ketones.

Specific examples of the technique of using these selenium sensitizers are disclosed in the following patent specifications. U.S. Patent No. 1,57
4,944, 1,602,592, 1,623,499, 3,297,4
No. 46, No. 3,297,447, No. 3,320,069, No. 3,408,196
No. 3,40,8197, 3,442,653, 3,420,670,
No. 3,591,385, French Patent No. 2,693,038, No. 2,093,
No. 209, etc., Japanese Patent Publication Nos. 52-34491 and 52-34492
No. 53-295, 57-22090, JP-A-59-180536,
59-185330, 59-181337, 59-187338, 59-
192241, 60-150046, 60-151637, 61-24673
No. 8, JP 3-4221, 3-24537, 3-111838, the same
3-116132, 3-148648, 3-237450, 4-16838
No. 4-52832, 4-32831, 4-96059, 4-109
No. 240, No. 4-140738, No. 4-140739, No. 4-147250,
4-149437, 4-184331, 4-190225, 4-9171
No. 29, No. 4-195035, etc., and British Patent No. 255846, No. 861984, each specification. HE Spencer et al. Journal
of Photographic Science, Vol. 31, pp. 158-169 (198
It is also disclosed in scientific literature such as 3).

The amount of the selenium sensitizer used varies depending on the selenium compound used, silver halide grains, chemical ripening conditions and the like, but generally about 10 ^-8 to 10 ^-4 mol per mol of silver halide is used. In addition, the addition method may be a method of adding it by dissolving it in water or an organic solvent such as methanol or ethanol alone or in a mixed solvent depending on the properties of the selenium compound used, or by adding it in advance with a gelatin solution. Alternatively, the method disclosed in JP-A-4-140739, that is, the method of adding in the form of an emulsion dispersion of a mixed solution with a polymer soluble in an organic solvent may be used.

The temperature of the chemical ripening using the selenium sensitizer is
The range of 40 to 90 ° C is preferable. More preferably, 45 ℃ ~ 80
℃. The pH is preferably in the range of 4-9 and the pAg is preferably in the range of 6-9.5.

The tellurium sensitizers and sensitization methods used in the chemical sensitization of the present invention are described in US Pat. No. 1,623,499.
Issue 3,320,069, Issue 3,772,031, Issue 3,531,289,
No. 3,655,394, British Patent No. 235,211, No. 1,121,496
No. 1,295,462, No. 1,396,696, Canadian Patent No. 800,
Each specification such as 958, JP-A-4-204640, and JP-A-4-333043
It is disclosed in each gazette such as the issue. Examples of useful tellurium sensitizers include telluroureas (eg, N, N-dimethyl tellurourea, tetramethyl tellurourea, N-carboxyethyl
-N, N'-dimethyl tellurourea, N, N'-dimethyl-N'-phenyl tellurourea), phosphine tellurides (eg, tributylphosphine telluride, tricyclohexylphosphine telluride, triisopropylphosphine telluride, butyl) -Diisopropylphosphine telluride, dibutylphenylphosphine telluride), telluroamides (for example, telluroacetamide, N, N-dimethyl tellurobenzamide), telluroketones, telluroesters, isotelloocyanates and the like.

The technique for using the tellurium sensitizer is in accordance with the technique for using the selenium sensitizer.

In the present invention, it is also preferable to use reduction sensitization in combination. The reduction sensitization is preferably performed during the growth of silver halide grains. As the method of applying during the growth, not only the method of performing reduction sensitization while the silver halide grains are growing, but also the method of performing reduction sensitization with the growth of silver halide grains being interrupted and then performing the reduction sensitization Also included are methods of growing the perceived silver halide grains.

In the present invention, sensitization with a noble metal salt such as a sulfur compound or a gold salt can be further carried out, or a combination of these methods can be used for sensitization.

In the present invention, it is preferred that a silver halide emulsion is constituted by adding fine grain silver iodide in the process from chemical ripening to coating. Here, during the process from the chemical ripening to the coating includes during the chemical ripening, and thereafter, when it is provided for coating to form a light-sensitive material, fine grain silver iodide is added until then. Means that. Further, the fine grain silver iodide used in the present invention will be described.

With respect to silver iodide, cubic γ-is generally used.
Although AgI and hexagonal β-AgI are known, the fine grain silver iodide used in the present invention may have any crystal structure or a mixture thereof.

In the present invention, fine grain silver iodide may be added at any step from the chemical ripening step to immediately before coating, but it is preferably added in the chemical ripening step. The term "chemical ripening step" as used herein refers to a period from the time when the physical ripening and desalting operations of the emulsion of the present invention are completed to the time when an operation for adding a chemical sensitizer and then stopping the chemical ripening is performed. Refers to. Further, the addition of fine grain silver iodide may be carried out in several times with a time interval, or another chemically ripened emulsion may be added after the addition of fine grain silver iodide. The temperature of the emulsion of the present invention when the fine grain silver iodide is added is preferably in the range of 30 to 80 ° C, more preferably 40 to 65 ° C. Further, the present invention is preferably carried out under the condition that after the addition of the fine grain silver iodide to be added, until just before coating, a part or all of the fine grain silver iodide disappears. More preferable condition is 20% of the fine grain silver halide added. The above is the disappearance just before coating.

The amount of disappearance is quantified by centrifuging the emulsion or coating solution after addition of fine grain silver iodide under appropriate conditions, and then
It can be carried out by measuring the absorption spectrum of the supernatant and comparing it with the absorption spectrum of a fine grain silver iodide solution of known concentration.

The development start point of the silver halide grains contained in the above-mentioned photosensitive silver halide emulsion is formed at or near the apex.

In the present invention, the formation of the development starting point at or near the apex means that the surface of the silver halide grain is coated with a silver halide adsorbing compound such as a spectral sensitizing dye or a stabilizer in the chemical sensitization step. However, by controlling the chemically sensitized nucleation site and / or by using a chemically sensitizer having reaction site selectivity.

The definition of the development starting point in the present invention is shown below. The value which defines (developing start point at the apex and the vicinity of the apex / total development start point) × 100 as the ratio (%) of the developing start point to the apex and the vicinity of the apex is 50% or more, more preferably 70% or more, and particularly It is preferably 90% or more.

Here, the vicinity of the vertex means that the center of the vertex is preferably 1/5 of the diameter corresponding to the area of the projected particles.
It preferably means a sector formed by lines separated by a length of 1/6. More preferably, the development starting point is on the side surface of the grain, and particularly preferably within 1/8 of the diameter of the circle, the effect becomes more remarkable.

In the present invention, the development starting point can be observed as follows. First, a light-sensitive material in which a target silver halide emulsion is coated on a support is exposed for 1 second and developed with a Kodak formulation MAA-1 developer at 20 ° C. for 10 minutes. Then, the exposure is performed from 10 times to 100 times the exposure amount that gives the maximum density of the obtained characteristic curve. Next, processing is carried out at 20 ° C. for 10 minutes with the following suppressed developer.

(Suppressed developer) Metol 0.45 g Ascorbic acid 3.0 g Borax 5.0 g KBr 1.0 g Surfactant 0.2 g Water added 1.0 l However, depending on the particle size and halogen composition, the development time, pH and development The temperature is changed so that minute development indicating the development starting point is easily observed. For example, 0.6 μm
For particles with the following particle sizes or with high AgCl content, pH
Or the development time may be shortened.

After the development as described above, the development was stopped with a 3% glacial acetic acid aqueous solution, the enzyme was decomposed with Actinase E without fixing, and silver halide grains were collected, and the silver halide grains were collected by a scanning electron microscope. Observe the position of developed silver. For example, the Hitachi S-900 model is used and observation is performed at a low acceleration voltage of 2 KV or less. In order not to generate printout silver, −
Observation at 170 ° C or lower is preferable.

In the present invention, the formation state of silver sulfide and / or silver gold sulfide can be observed by an electron microscope, and in particular, the method described in JP-A-61-93447, that is,
It can be observed using a transmission electron microscope observation method by a gelatin foreskin method.

The silver halide grains of the silver halide emulsion used in the present invention include silver halides such as silver bromide, silver iodobromide, silver iodochloride, silver chlorobromide, silver chloroiodobromide and silver chloride. Although silver particles can be used optionally, silver iodobromide and silver chloroiodobromide are particularly preferred.

The silver halide grains used in the present invention may have any shape, but tabular grains are particularly preferred.

The tabular grains preferably used in the present invention will be described below.

The tabular silver halide grains used in the present invention are crystallographically classified as twin crystals. Twins are silver halide crystals that have one or more twin planes in one grain.The morphology of twins is classified by Klein and Moiser in the article Photographie Correspondents (Photogr
aphisches Korrespondenz) 99, 99, 100, 57.

The tabular silver halide grains used in the present invention mainly have an even number of parallel twin planes, and these twin planes may or may not be parallel to each other. Particularly preferably, it has two twin planes.

The tabular silver halide grains used in the present invention have an average value of the ratio of grain diameter / thickness (aspect ratio).
(Average aspect ratio) is 2 or more. The tabular silver halide grains used in the present invention have an average aspect ratio of preferably 2 or more and 12 or less, and more preferably 3 to 8.

The outer wall of the crystal of the tabular silver halide grains according to the present invention may be substantially composed of {111} planes or {100} planes. Further, it may have both a {111} plane and a {100} plane. In this case, 50% or more of the grain surface is a {111} plane, more preferably 60% to 90% is a {111} plane, and particularly preferably 70 to 95% is a {111} plane. It is preferable that the planes other than the {111} plane are mainly the {100} plane. This plane ratio is {111} plane and {100} plane in the adsorption of sensitizing dye.
Utilizing the difference in adsorption dependence with the surface [T. Tani, J. Imaging
Sci. 29,165 (1985)].

The tabular silver halide grains according to the present invention are
It may be polydisperse or monodisperse, but is preferably monodisperse. Specifically, (standard deviation of particle size / average particle size) x 100 = width of particle size distribution
When the width of the distribution is defined by the relative standard deviation (coefficient of variation) that can be expressed by (%), it is preferably 25% or less, more preferably 20% or less, and particularly preferably 15% or less.

The tabular silver halide grains of the present invention preferably have a small thickness distribution. Specifically, (standard deviation of thickness / average thickness) x 100 = width of thickness distribution
When the breadth of distribution is defined by (%), it is preferably 25% or less, more preferably 20% or less, and particularly preferably 15% or less.

Further, it is preferable that the distribution of the halogen content of each grain in the tabular silver halide grain emulsion of the present invention is also small. Specifically, (standard deviation of halogen content / average halogen content) x 10
0 = 25% or less is preferable when the breadth of the halogen content is defined by the breadth (%) of the halogen content, more preferably 20% or less, and particularly preferably 15% or less.

In the present invention, the tabular silver halide grains are preferably hexagonal. Hexagonal tabular grains
(Hereinafter also referred to as hexagonal tabular grains) means its main plane ({111}
The shape of (face) is hexagonal, and the maximum adjacency ratio is 1.0 to 2.
Say it is 0. Here, the maximum adjacent side ratio is the ratio of the length of the side having the maximum length to the length of the side having the minimum length forming a hexagon. In the present invention, it is also preferable that the hexagonal tabular grains have rounded corners if the maximum adjacent side ratio is 1.0 to 2.0. When the corner is rounded, the length of the side is represented by the distance between the straight line portion of the side and the intersection with the line obtained by extending the straight line portion of the adjacent side. Further, it is also preferable that the tabular grains are more rounded and have a substantially circular shape.

In the present invention, each side forming the hexagon of the hexagonal tabular grain preferably has a half or more of a substantially straight line. In the present invention, the ratio of adjacent sides is 1.0 to
It is more preferably 1.5.

The silver halide grains according to the present invention may have dislocations. The rearrangement is, for example, JF Hamilton, Phot.S.
ci.Eng, 57 (1967), T.Shiozawa, J.Soc.Phot.Sci.Jap
It can be observed by a direct method using a transmission electron microscope at low temperature described in an, 35, 213 (1972). That is, the silver halide grains, which were taken out carefully so as not to apply pressure enough to cause dislocation to the grains from the emulsion, were placed on the mesh for electron microscope observation, and the sample was taken to prevent damage (printout etc.) due to electron beams. In the cooled state, observation is performed by the transmission method. At this time, the thicker the particles, the more difficult it is for the electron beam to penetrate, so it is possible to observe more clearly by using a high-pressure electron microscope (200 KV or more for particles having a thickness of 0.25 μm). .

The position and number of dislocations in each grain can be determined from the photograph of the grain obtained by such a method. The position of dislocation of the silver halide grain according to the present invention is 0.58 L from the center of the halide grain toward the outer surface.
It is desirable that it occurs in a region of up to 1.0 L, but more preferably it occurs in a region of 0.80 L to 0.98 L. The direction of the dislocation line is approximately from the center to the outer surface, but it often meanders.

In the present invention, the center of a silver halide grain means that silver halide microcrystals are dispersed in a methacrylic resin in the same manner as the method described in the summary of Inoue et al. When solidified and made into an ultrathin section with a microtome, and focusing on the section sample with the maximum cross-sectional area and the cross-sectional area of 90% or more than that, when drawing the minimum circumscribed circle to the cross section Is the center of the circle. In the present invention, the distance L from the center to the outer surface is defined as the distance between the center of the circle and the point intersecting the outer circumference of the particle when a straight line is drawn outward from the center of the circle.

With respect to the number of dislocations in the silver halide grain according to the present invention, it is desirable that 50% (number) or more of grains containing one or more dislocations are present, and the ratio of the number of tabular grains having dislocation lines (number) ) Is higher, the more preferable. In the present invention, the particle size is a diameter when a projected image of particles is converted into a circular image having the same area. The projected area of a grain can be calculated from the sum of the grain areas. All of them can be obtained by observing, with an electron microscope, a silver halide crystal sample distributed on the sample stage to the extent that grains do not overlap.

The average projected area diameter of the tabular silver halide grains in the present invention is represented by the diameter corresponding to the circle of the projected area of the grains, preferably 0.30 μm or more, but more preferably
It is 0.30 μm to 5 μm, more preferably 0.40 μm to 2 μm.

The particle size can be obtained by enlarging and projecting the particles with an electron microscope at a magnification of 10,000 to 70,000 and measuring the area of the projected image on the print.

The average particle diameter (φi) can be calculated by the following equation, where n is the number of measured particle diameters and ni is the frequency of particles having a particle diameter di.

Average particle diameter (φi) = Σnidi / n (The number of measured particles is indiscriminately 1,000 or more.) The particle thickness can be obtained by observing the sample obliquely with an electron microscope. . The preferred thickness of the tabular grains of the present invention is 0.03-1.0 μm, more preferably
It is 0.05 to 0.5 μm.

The longest distance (a) between two or more parallel twin planes of the silver halide grain of the present invention and the grain thickness (b).
The ratio (b / a) is preferably 5 or more, and the ratio is preferably 50% (number) or more.

The twin plane distance (a) can be obtained as follows. That is, observation of the section using the above transmission electron microscope, with respect to the main plane, arbitrarily select 100 or more tabular silver halide grains showing a cross section cut substantially perpendicularly, for each grain ( It can be obtained by measuring a) and averaging them.

In the present invention, the average value of (a) is 0.008 μm.
Or more, but more preferably 0.010 μm or more,
It is 0.05 μm or less.

Further, in the present invention, it is necessary that (a) is within the above value range, and at the same time, its coefficient of variation is not more than 35%, preferably not more than 30%.

Further, in the present invention, the tabularity expressed by the following equation: A in consideration of factors of aspect ratio and grain thickness: A
= ECD / b ² is preferably 20 or more.

Here, ECD is the average projected diameter of tabular grains.
(b) is the thickness of the particles.

The average projected diameter here means the number average of the diameters of circles having an area equal to the projected area of tabular grains.

The tabular silver halide grains used in the present invention may have a uniform composition, but a core / shell structure having at least two layer structures having substantially different halogen compositions within the silver halide grains. It is preferred that the number of grains having the number of 50% or more and 100% by number is contained in the photosensitive silver halide emulsion layer.

The core / shell type structured grain may have a halogen composition region different from that of the core in the center of the grain. The halogen composition of the seed grains in such a case may be any combination of silver bromide, silver iodobromide, silver chloroiodobromide, silver chlorobromide, silver chloride and the like.

The average silver iodide content of the silver halide emulsion according to the present invention is preferably 2 mol% or less, more preferably
It is 0.01 to 1.5 mol%. In the grains having a layer structure having different halogen compositions, grains having a high silver iodide layer inside the grain and a low silver iodide layer or a silver bromide layer at the outermost surface layer are preferable. At this time, the silver iodide ratio of the inner layer (core) having the highest silver iodide content is preferably 2.5 mol% or more, more preferably 5 mol% or more, and the iodide of the outermost surface layer (shell) is The silver content is 0 to 5 mol%, preferably 0 to 3 mol%, and the silver iodide content of the core is preferably at least 3 mol% or more than the silver iodide content of the shell.

The silver iodide distribution of the core is usually uniform, but it may have a distribution. For example, the concentration may increase from the center toward the outside, or may have a maximum or minimum concentration in the intermediate region.

The silver halide grains used in the present invention are
So-called halogen conversion type particles may be used. The amount of halogen conversion is preferably 0.2 mol% to 2.0 mol% with respect to the amount of silver, and the conversion time may be physical ripening or after physical ripening. As a method for converting halogen, an aqueous solution of halogen or silver halide fine particles having a smaller solubility product with silver than the halogen composition on the surface of the grain before halogen conversion is usually added. The fine particle size at this time is preferably 0.2 μm or less, more preferably 0.02 to 0.1.
μm. The silver halide grains of the present invention are preferably grown by a method of precipitating silver halide on a seed crystal such as the method described in Examples of JP-A-60-138538.

In order to obtain the tabular silver halide emulsion of the present invention, a method for producing a silver halide photographic emulsion comprising supplying a water-soluble silver salt solution and a water-soluble halide solution in the presence of a protective colloid, (A) A nucleus grain forming step of maintaining the pBr of the mother liquor at 2.5 to -0.7 for a period of 1/2 or more from the initial stage of silver halide precipitation formation having a silver iodide content of 0 to 5 mol%, (b)
Subsequent to the step of forming the nucleus grains, the mother liquor contains a silver halide solvent in an amount of 10 ^{−5 to} 2.0 mol per mol of the silver halide to form substantially monodisperse spherical twin crystal silver halide seed grains. Providing a seed grain forming step, or subsequent to the core grain forming step, raising the temperature of the mother liquor to 40 to 80 ° C., and providing a seed grain forming step of forming silver halide twin seed grains,
(C) Next, a method of providing a growth step of enlarging seed particles by adding a water-soluble silver salt solution and a water-soluble halide solution and / or halogenated fine particles is preferably used.

Here, the mother liquor is a liquid (including a silver halide emulsion) that is used for the preparation of silver halide emulsions up to the completed photographic emulsion.

The silver halide grains formed in the above grain forming step are twin grains composed of 0 to 5 mol% of silver iodide.

A water-soluble silver salt may be added for the purpose of controlling ripening during the seed grain forming step of the present invention.

The seed grain growing step for enlarging the silver halide seed grains is carried out by the following steps: during precipitation of silver halide, during the aging of Ostwald, pH, pH, temperature, concentration of silver halide solvent, silver halide composition, silver halide and halogen. This is achieved by controlling the addition rate of the chloride solution.

In the preparation of the emulsion according to the present invention, a known silver halide solvent such as ammonia, thioether or thiourea can be present during the seed grain forming step and the seed grain growth.

Conditions for enlarging the produced seed grains in order to obtain the tabular silver halide grains according to the present invention include, for example, JP-A Nos. 51-39027, 55-142329, and 58-113928.
No. 54-48521 and No. 58-49938, the water-soluble silver salt solution and the water-soluble halide solution were added by the double jet method, and the addition rate was changed according to the enlargement of the particles. You may use the method of changing gradually in the range in which nucleation does not occur and Ostwald ripening does not occur. As another condition for enlarging the seed grains, a method for enlarging by adding silver halide fine particles and dissolving and recrystallizing can be used as shown in Section 88 of the 1983 Annual Meeting of the Photographic Society of Japan.

For growth, an aqueous solution of silver nitrate and an aqueous solution of halide can be added by the double jet method, but iodide can also be supplied to the system as silver iodide.
The rate of addition is such that no new nuclei are generated, and there is no spread of the size distribution due to Ostwald ripening,
That is, it is preferable to add in a range of 30 to 100% of the rate at which new nuclei are generated.

In the production of the silver halide emulsion of the present invention, the stirring conditions during production are extremely important. As the stirring device, a device in which the additive liquid nozzle disclosed in JP-A-62-160128 is installed in the liquid near the mother liquor suction port of the stirrer is particularly preferably used. At this time, the stirring rotation speed is 400
It is preferably set to ~ 1200 rpm.

The silver iodide content and the average silver iodide content of the silver halide grains of the present invention are determined by the EPMA method (Electron Probe Micr
o Analyzer) can be used. According to this method, a sample in which emulsion grains are well dispersed so that they do not come into contact with each other is prepared, and elemental analysis of a smaller portion than X-ray analysis by electron beam excitation with electron beam irradiation can be performed. By this method, the halogen composition of each grain can be determined by obtaining the characteristic X-ray intensities of silver and iodide emitted from each grain. E for at least 100 particles
If the silver iodide content is obtained by the PMA method, the average silver iodide content is obtained from the average of them.

In the production of the light-sensitive silver halide emulsion of the present invention, the seed emulsion has two or more twin planes in which 50% or more of the total projected area of the seed grains are parallel to each other, and Both the variation coefficient and the variation coefficient of the longest distance (at) between twin planes of the seed grains are preferably 35% or less.

Even if the variation coefficient of only the thickness of the seed grain or only of (at) is 35% or less, it is possible to suppress the variation coefficient of the twin plane distance (a) of the grain after growth to 35% or less. It is not possible, and it is necessary for both to be established at the same time.

It is generally considered that twin planes are formed at the stage of nucleation, but it is considered that some twin planes are formed during growth.

Further, the silver halide grain according to the present invention, in the process of forming and / or growing the grain, cadmium salt, zinc salt, lead salt, thallium salt, iridium salt (including complex salt), rhodium salt ( It is possible to add at least one metal ion selected from the group consisting of complex salts) and iron salt (including complex salts) to make these metal elements contained inside the particles and / or in the surface layer of the particles. The reduction sensitizing nuclei can be imparted to the inside of the grain and / or the surface of the grain by exposing the grain to a selective atmosphere.

Further, the action of the reducing agent added at a desired time of grain formation is to add an oxidizing agent such as hydrogen peroxide (water) and its adduct, peroxo acid salt, ozone and I ₂ at a desired time. It is preferable to inactivate by and suppress or stop the reduction.

The timing of adding the oxidizing agent can be arbitrarily selected from the time of silver halide grain formation to the chemical sensitization step.

In the silver halide emulsion of the silver halide photographic light-sensitive material according to the present invention, unnecessary soluble salts may be removed at the end of the growth of the silver halide grains, or may be kept contained. The salts can be removed by the method described in Research Disclosure (hereinafter abbreviated as RD) No. 17643 No. II.

The silver halide emulsion layer containing the group of grains in the present invention may contain grains of various shapes as long as the effects of the present invention are not impaired.

When any of at least one of the layers containing the light-sensitive silver halide emulsion of the present invention or the constituent layers other than the emulsion layer contains a dye capable of being decolorized or / and flowed out during the development processing, A light-sensitive material having high sensitivity, high sharpness and less dye stain can be obtained. The dye used in the light-sensitive material may be appropriately selected from dyes capable of improving sharpness by absorbing a desired wavelength and removing the influence of the wavelength, depending on the light-sensitive material. I can. It is preferable that the dye be decolorized or flowed out during the development processing of the light-sensitive material, and the coloring should not be visible when the image is completed. It is effective to add it in the coating layer adjacent to the transparent support. The dye preferably has a high concentration on the side close to the support.

In the present invention, the amount of the above dye added can be changed according to the sharpness target. ^{Preferably, 0.2mg / m 2 ~20mg / m} 2, more preferably, 0.8 mg / m ²
It is a ~15mg / m ^2. The above dye can be introduced into the hydrophilic colloid layer by a conventional method.

In the light-sensitive material of the present invention, when the silver halide emulsion layer is colored, these solutions are added to the support before they are added to the silver halide emulsion solution before coating or to the aqueous solution of the hydrophilic colloid. It may be applied to the surface directly or through another hydrophilic colloid layer by various methods.

As described above, it is preferable that the dye has a high concentration on the side closer to the support. However, in order to fix the dye on the side closer to the support in this way, a moldant can be used. Various photographic additives can be used in the silver halide light-sensitive material according to the present invention. Known additives include, for example, the compounds described in Research Disclosure No. 17643 (December 1978), No. 18716 (November 1979) and No. 308119 (December 1989). The types of compounds shown in these three research disclosures and the locations where they are described are listed below.

Additives RD-17643 RD-18716 RD-308119 Page Classification Page Page Classification Chemical sensitizer 23 III 648 Upper right 996 III Sensitizing dye 23 IV 648-649 996-8 III Desensitizing dye 23 IV 998 B Dye 25 ~ 26 VIII 649 ~ 650 1003 VIII Development accelerator 29 XXI 648 Upper right fog inhibitor / stabilizer 24 IV 649 Upper right 1006 ~ 7 VI Whitening agent 24 V 998 V Surfactant 26 ~ 27 XI 650 Right 1005 ~ 6 XI Charge Inhibitor 27 XII 650 Right 1006 to 7 XIII Plasticizer 27 XII 650 Right 1006 XII Sliding agent 27 XII Matting agent 28 XVI 650 Right 1008 to 9 XVI Binder 26 XXII 1009 to 4 XXII Support 28 XVII 1009 XVII The silver halide emulsions may contain a developing agent such as aminophenol, ascorbic acid, pyrocatechol, hydroquinone, phenylenediamine or 3-pyrazolidone in the emulsion layer or in layers with other layers.

Examples of the support that can be used in the light-sensitive material of the present invention include the above-mentioned RD-17643, page 28 and RD.
-308119, page 1009.

A suitable support is a plastic film or the like, and the surface of these supports may be provided with an undercoat layer, corona discharge, ultraviolet irradiation or the like in order to improve the adhesion of the coating layer.

Next, preferable development processing of the light-sensitive material of the present invention will be described.

Preferred developing solutions for developing the light-sensitive material of the present invention include, as developing agents, dihydroxybenzenes described in JP-A-4-15641 and JP-A-4-16841, such as hydroquinone and para-aminophenols.
Examples of 3-pyrazolidones such as p-aminophenol, N-methyl-p-aminophenol, and 2,4-diammiphenol include 1-phenyl-3-pyrazolidones, 1-phenyl-3-pyrazolidone, 1 -Phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone, 5,5-dimethyl-1-phenyl
It is preferable to use -3-pyrazolidone or the like, or to use them in combination.

The amount of the para-aminophenols and 3-aminopyrazolidones used is preferably 0.004 mol / liter, more preferably 0.04-0.12 mol / liter.

Further, the total number of moles of dihydroxybenzenes, paraaminophenols and 3-pyrazolidones contained in the components of all developing solutions is preferably 0.1 mol / liter or less.

Preservatives may include sulfites such as potassium sulfite, sodium sulfite, reductones such as piperidinohexose reductone,
These are preferably used in an amount of 0.2 to 1 mol / liter, more preferably 0.3 to 0.6 mol / liter. Further, addition of a large amount of ascorbic acid also leads to processing stability.

As the alkaline agent, sodium hydroxide,
Includes pH adjusters such as potassium hydroxide, sodium carbonate, potassium carbonate, sodium triphosphate, potassium triphosphate. Further, the borate described in JP-A-61-28708,
Saccharose, acetoxime described in JP-A-60-93439,
A buffering agent such as 5-sulfosalicylic acid, phosphate or carbonate may be used. The content of these chemicals is such that the pH of the developer is 9.0
-13, preferably pH 10-12.5.

As the solubilizing agent, polyethylene glycols and their esters, and as the sensitizing agent,
For example, a development accelerator, a surfactant, etc. such as a quaternary ammonium salt can be contained.

As a silver sludge preventive agent, JP-A-56-106 has been used.
Anti-staining agent for silver described in JP-A No. 244, sulfide, disulfide compound described in JP-A-3-51844, Japanese Patent Application No. 4-92947
A cysteine derivative or a triazine compound described in JP-A No. 1993-242242 is preferably used.

As the organic inhibitor, an azole type organic antifoggant, for example, an indazole type, imidazole type, benzimidazole type, triazole type, benztriazo type, tetrazole type or thiadiazole type compound is used. Inorganic inhibitors include sodium bromide, potassium bromide, potassium iodide and the like. In addition, LFA Menson's "Photographic Processing Chemistry" published by Focal Press (1966), 226-229.
Page, U.S. Pat.Nos. 2,193,015 and 2,592,364,
Those described in JP-A-48-64933 may be used. The chelating agent for masking calcium ions mixed in tap water used in the treatment liquid is preferably a chelating agent having a chelate stabilization constant with iron of 8 or more as described in JP-A 1-193853 as an organic chelating agent. Used.
Examples of the inorganic chelating agent include sodium hexametaphosphate, calcium hexametaphosphate, and polyphosphate.

As the development hardening agent, a dialdehyde compound may be used. In this case, glutaraldehyde is preferably used. However, for rapid processing as described below, rather than having the developer contain a hardener and allowing the hardener to act in the developing process, the developer is preliminarily contained in the silver halide light-sensitive material and the developing process is carried out. It is more desirable to adjust the degree of hardening so that the swelling rate is appropriate.

The processing temperature of the developer of the present invention is preferably
The temperature is 25 to 50 ° C, more preferably 30 to 40 ° C. The development time is 5 to 90 seconds, more preferably 8 to 60 seconds. The treatment time is Dry to Dry, preferably 20 to 210 seconds, more preferably 30 to 90 seconds.

The replenishment in the present invention replenishes the treatment agent fatigue and oxidative fatigue. As a replenishment method, JP-A-55-126
Replenishment according to width and feeding speed described in Japanese Patent No. 243, JP-A-60-
Area replenishment described in JP-A-104946 and area replenishment controlled by the number of continuously processed sheets described in JP-A-1-149156 may be used, and a preferable replenishing amount is 500 to 150 cc / m ² .

Preferred fixing solutions can include fixing materials commonly used in the art. The pH is 3.8 or higher, preferably 4.2 to 5.5. The fixing agent is a thiosulfate such as ammonium thiosulfate or sodium thiosulfate, and ammonium thiosulfate is particularly preferable from the viewpoint of fixing speed. The concentration of the ammonium thiosulfate is preferably in the range of 0.1 to 5 mol / l, more preferably 0.8 to 3 mol / l.

The fixing solution of the present invention may be one which performs acidic hardening. In this case, aluminum ions are preferably used as the hardener. For example, it is preferably added in the form of aluminum sulfate, aluminum chloride, potassium alum, or the like.

Others In the fixing solution of the present invention, if desired, preservatives such as sulfite and bisulfite, pH buffers such as acetic acid and boric acid, mineral acids (sulfuric acid, nitric acid) and organic acids (citric acid, oxalic acid). , Malic acid, etc.), various acids such as hydrochloric acid, and pH adjusting agents such as metal hydroxides (potassium hydroxide, sodium hydroxide) and chelating agents having a water softening ability.

As the fixing accelerator, for example, JP-B-45-357.
No. 54, No. 58-122535 and No. 58-122536, and the thioethers described in US Pat. No. 4,126,459.

The silver halide emulsion layer of the present invention preferably has a swelling ratio during development of 150 to 250% and a film thickness after expansion of 70 μm or less. If the water swelling rate exceeds 250%, poor drying occurs, and, for example, poor handling occurs in automatic processor processing, especially rapid processing. Further, if the water swelling ratio is less than 150%, uneven development and residual color tend to be deteriorated during development. Here, the water swelling rate means the difference between the film thickness after swelling in each processing solution and the film thickness before the development processing, which is divided by the film thickness before processing and multiplied by 100. .

[0149]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited thereto.

Example-1 (Preparation of seed emulsion-1) Seed emulsion-1 was prepared as follows.

A1 ossein gelatin 24.2 g water 9657 ml polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt (10% ethanol aqueous solution) 6.78 ml potassium bromide 10.8 g 10% nitric acid 114 ml B1 2.5N silver nitrate aqueous solution 2825 ml C1 potassium bromide 824 g Potassium iodide 23.5 g Water with 2825 ml D1 1.75N aqueous potassium bromide solution A1 solution using the mixing stirrer disclosed in Japanese Patent Publication Nos. 58-58288 and 58-58289 at the following silver potential control amount of 42 ° C. B1 and solution C
Nucleation was carried out by adding 464.3 ml each of 1 by the simultaneous mixing method over 1.5 minutes.

After stopping the addition of solution B1 and solution C1, it took 60 minutes to raise the temperature of solution A1 to 60 ° C., adjust the pH to 5.0 with 3% KOH, and then add solution B1 again. Solution C1 was mixed by the simultaneous mixing method at a flow rate of 55.4 ml / min.
Added for 2 minutes. This temperature rise from 42 ° C to 60 ° C and solution B
The silver potentials (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) during re-simultaneous mixing by 1 and C1 were controlled to +8 mv and +16 mv, respectively, using the solution D1.

After completion of the addition, the pH was adjusted to 6 with 3% KOH, and desalting and washing with water were immediately performed. This seed emulsion has a maximum adjacent side ratio of 1.0 to 90% of the total projected area of silver halide grains.
It was confirmed by an electron microscope that the hexagonal tabular grains of 2.0 had an average thickness of 0.06 μm and an average grain size (converted to a circle diameter) of 0.59 μm. The coefficient of variation of thickness is 40
%, And the coefficient of variation in the distance between twin planes was 42%.

(Preparation of Em-1) A tabular silver halide emulsion Em-1 having an average silver iodide content of 1.0 mol% was prepared by using seed emulsion-1 and the following four kinds of solutions.

A ossein gelatin 34.03 g polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt (10% ethanol aqueous solution) 2.25 ml seed emulsion-1 1.218 mol equivalent Water to make 3150 ml B potassium bromide 1976 g water 4151 ml Finishing C Silver nitrate 2468 g Finishing to 4151 ml with water D 3% by weight of gelatin and silver iodide grains (average grain size 0.05μ) Fine grain emulsion (*) Equivalent to 0.145 mol * 0.06 mol containing 0.06 mol potassium iodide % Gelatin aqueous solution (6.64 liters), 2 liters each containing 7.06 mol of silver nitrate and 7.06 mol of potassium iodide were added over 10 minutes. The pH during the formation of fine particles was 2.0 using nitric acid, and the temperature was 4
The temperature was controlled at 0 ° C. After the particle formation, the pH was adjusted to 6.0 using an aqueous sodium carbonate solution.

Solution A was vigorously stirred in the reaction vessel while maintaining the temperature at 60 ° C., and a part of solution B, a part of solution C and the total amount of solution D were added thereto by the simultaneous mixing method over 46 minutes, After that, the remaining amounts of the solution B and the solution C were continuously added over 24 minutes by the simultaneous mixing method. During this period, pH was kept at 5.8 and pAg was kept at 9.0. Here, the addition rates of the solution B and the solution C were changed in a function-like manner with respect to time so as to match the critical growth rate. That is, the addition was performed at an appropriate addition rate so that small particles were not generated other than the growing seed particles and polydispersion did not occur due to Ostwald ripening. The addition rate of the solution D was changed with the rate ratio (molar ratio) with the solution C as shown in Table 3.

[0157]

[Table 3]

After the completion of the addition, this emulsion was cooled to 40 ° C., and a 13.8% (weight) aqueous solution of modified gelatin modified with phenylcarbamoyl groups (a substitution rate of 90%) as an aggregating polymer agent 1800
ml was added and stirred for 3 minutes. Thereafter, a 56% (weight) acetic acid aqueous solution was added to adjust the pH of the emulsion to 4.6, the mixture was stirred for 3 minutes, allowed to stand for 20 minutes, and the supernatant was drained by decantation. Then, 9.0 l of distilled water at 40 ° C was added, and the supernatant was drained after standing with stirring, 11.25 l of distilled water was further added, and after standing with stirring, the supernatant was drained. Subsequently, a gelatin aqueous solution and a 10% (weight) aqueous sodium carbonate solution were added to adjust the pH to 5.80, and the mixture was stirred at 50 ° C. for 30 minutes and redispersed. After redispersion at 40 ℃ pH 5.80, pAg 8.0
Adjusted to 6.

When the obtained silver halide emulsion was observed with an electron microscope, tabular silver halide grains having an average grain size of 0.98μ, an average thickness of 0.22μ, an average aspect ratio of about 4.6, and a grain size distribution of 18.9% were obtained. Met. Also, the average distance between twin planes is
It was 0.018μ. Incidentally, grains having a thickness / twin plane distance ratio of 10 or more contain 50% or more of all grains.

Next, the effect of the present invention was examined by using the silver halide emulsion thus obtained.

First, in order to evaluate the effects of the method of adding a spectral sensitizing dye as a methanol solution and the method of adding it as a solid fine particle dispersion, emulsion Em-1 was subjected to the following spectral sensitization and chemical sensitization. Seed formulation was applied.

(Formulation A) After the emulsion was heated to 60 ° C., a solution of the spectral sensitizing dyes (I-56) and (II-2) in methanol was added, and then ammonium thiocyanate, chloroauric acid and sodium thiosulfate were added. A mixed aqueous solution and a silver iodide fine grain emulsion were added and the mixture was ripened for 2 hours. At the end of aging, stabilizer 4-
Hydroxy-6-methyl-1,3,3a, 7-tetrazaindene (T
AI) was added.

(Formulation B) The above-mentioned Formula A is different only in that the spectral sensitizing dye is added as a dispersion in the form of solid fine particles instead of being added as a methanol solution. The dispersion was prepared by a method according to Japanese Patent Application No. 4-99437. That is, a predetermined amount of the above spectral sensitizing dye was added to water whose temperature was previously adjusted to 27 ° C., and a high-speed stirrer (dissolver) was operated at 3500 rpm.
It was obtained by stirring at 30-120 min.

The amounts of the above additives are shown below.

Spectral sensitizing dye (I-56) 4 mg (/ mol Ag) Spectral sensitizing dye (II-2) 410 mg Potassium thiocyanate 95 mg Chloroauric acid 2.5 mg Sodium thiosulfate 2.5 mg Silver iodide fine particles 850 mg Stabilizer (TAI) 1 g In addition, when the spectral sensitizing dye was added as a solid fine particle dispersion, the addition amount was changed.

Next, the following additives were added to the emulsion thus sensitized to prepare an emulsion layer coating solution. At the same time, a protective layer coating solution was also prepared.

The coating amount was 2.0 g / m ² on one side and the amount with gelatin was 3.1 g / m ² using two slide hopper type coaters, and both sides were coated simultaneously on the support. A sample was obtained after drying. The support is a 175 μm thick, 0.15 concentration blue-colored polyethylene terephthalate film base for X-rays, and a copolymer consisting of three types of monomers of 50 wt% glycidyl methacrylate, 10 wt% methyl acrylate, and 40 wt% butyl methacrylate on both sides. The concentration of
The following copolymer dyes were dispersed in an aqueous copolymer dispersion obtained by diluting to 10 wt% and applied as an undercoating liquid.

Filter dye (solid dispersion)

[0169]

[Chemical 5]

Additives added to the emulsion are as follows.
The addition amount is indicated by the amount per mol of silver halide.

1,1-Dimethylol-1-bromo-1-nitromethane 70 mg t-Butyl-catechol 400 mg Polyvinylpyrrolidone (molecular weight 10,000) 1.0 g Styrene maleic anhydride copolymer 2.5 g Nitrophenyl-triphenylphosphonium chloride 50 mg 1, Ammonium 3-dihydroxybenzene-4-sulfonate 2.0 g C ₄ H ₉ OCH ₂ CH (OH) CH ₂ N (CH ₂ COOH) ₂ 1.0 g 1-phenyl-5-mercaptotetrazole 15 mg

[0172]

[Chemical 6]

Protective Layer Solution Next, the following was prepared as a protective layer coating solution. The additive is shown in the amount per liter of coating liquid.

Lime-treated inert gelatin 68 g Acid-treated gelatin 2.0 g Sodium-i-amyl-n-decylsulfosuccinate 1.0 g Polymethylmethacrylate (matting agent having an area average particle size of 3.5 μm) 1.1 g Silicon dioxide particles (area average particles Matte agent with a diameter of 1.2 μm) 0.5 g (CH ₂ = CHSO ₂ CH ₂ ) ₂ (hardener) 500 mg C ₄ F ₉ SO ₃ K 2.0 mg C ₁₂ H ₂₅ CONH (CH ₂ CH ₂ O) ₅ H 2.0 g

[0175]

[Chemical 7]

FIG. 1 shows a part of the result of spectroscopic spectrum measurement of the sample thus obtained. It was found that the addition of the solid fine particle dispersion unexpectedly yields a spectral absorption spectrum equal to or higher than that of the methanol solution as compared with the case of adding it as a methanol solution.

In the case of the latter addition method, it was confirmed that the amount of the spectral sensitizing dye added was small, so that the residual dye after the development treatment was small (see Table 4).

[0178]

[Table 4]

Example-2 Based on the findings of Example-1, emulsion Em-1 was continuously prepared.
To 60 ° C., and then a predetermined amount of the spectral sensitizing dye shown in Table 5 was added as a solid fine particle dispersion, and then a mixed aqueous solution of ammonium thiocyanate, chloroauric acid and sodium thiosulfate and N, N- Add a solution of dimethylselenourea in methanol and, after 60 minutes, add silver iodide fine grain emulsion for a total of 2
Aged for time. As a stabilizer at the end of aging (TA
An appropriate amount of I) was added.

The addition amount of N, N-dimethylselenourea was 0.
4 mg / Ag mol, other additives were added in the same amounts as in Example 1.

[0181]

[Table 5]

Then, the silver halide emulsion prepared as described above was coated in the same manner as in Example 1 to obtain a sample.

Next, each of the obtained samples No. 1 to No. 26 was subjected to two kinds of conditions (condition A: 23 ° C., 55% RH, condition B: 40).
Photographic properties were evaluated after storage at 4 ° C. and 80% RH for 4 days.

The evaluation method is as follows. First, two samples of intensifying screen KO-2 were used.
It was sandwiched between 50 (manufactured by Konica Corp.) and irradiated with an X-ray for 0.05 second at a tube voltage of 80 kvp and a tube current of 100 mA through an aluminum wedge for exposure. Then, using an automatic processor SRX-502 (manufactured by Konica Corporation), processing was performed with a developing solution and a fixing solution having the following formulations.

Developer Formulation Part-A (for finishing 12 liters) Potassium hydroxide 450 g Potassium sulfite (50% solution) 2280 g Diethylenetetraamine-5-acetic acid 120 g Sodium bicarbonate 132 g 5-Methylbenzotriazole 1.2 g 1-phenyl-5- Mercaptotetrazole 0.2g Hydroquinone 340g Add water to make 5000ml.

Part-B (for finishing 12 liters) Glacial acetic acid 170 g Triethylene glycol 185 g 1-Phenyl-3-pyrazolidone 22 g 5-Nitroindazole 0.4 g Starter glacial acetic acid 120 g Potassium bromide 225 g Add water to make 1.0 l.

Fixer Formulation Part-A (For 18l Finishing) Ammonium thiosulfate (70wt / vol%) 6000g Sodium sulfite 110g Sodium acetate trihydrate 450g Sodium citrate 50g Gluconic acid 70g 1- (N, N-dimethylamino) -Ethyl-5-mercaptotetrazole 18g Part-B Aluminum sulphate 800g To prepare the developer, add Part A and Part B to 5 liters of water at the same time, add water while stirring and dissolve and add 12 liters to pH with glacial acetic acid.
Was adjusted to 10.40. This is used as a developing solution.

20 ml / l of the aforesaid starter was added to 1 liter of this developing solution to adjust the pH to 10.26 to prepare a working solution.

The fixing solution was prepared by adding Part A and Part B to about 5 liters of water.
Was simultaneously added, water was added while stirring and dissolving to make 18 l, and the pH was adjusted to 4.4 using sulfuric acid and NaOH. This is the fixing replenisher.

The processing temperatures are 35 ° C. for development and fixing, respectively.
33 ℃, 20 ℃ water wash, 50 ℃ dry, treatment time is dry to dry 45
Seconds.

After the treatment, the sensitivity was measured. Sensitivity is expressed as the reciprocal of the exposure dose that gives a density of fog + 0.5
The relative sensitivity is shown when the sensitivity of 26 (storage condition A) is 100. The results obtained are shown in Table 6 below.

[0192]

[Table 6]

As is clear from Table 6, the spectral sensitizing dye I
-4, I-15, I-16, I-55, I-56, and II-2 were compared with two types of spectra obtained by the method according to the present invention from comparative samples sensitized with only one type of spectral sensitizing dye. It can be seen that the sample sensitized by the combined use of the sensitizing dyes is excellent in sensitivity and fluctuating sensitivity and fog even when stored under high temperature and high humidity. Further, it is found that the sensitivity is higher when the development starting point is formed at the vertex and / or in the vicinity thereof.

The safelight property was evaluated by irradiating each sample through a red filter having the transmittance shown in FIG. 2 with light from a white light bulb from 1.2 m above the sample for 30 minutes, followed by development and fog in the same manner as described above. The increase value of was measured as the safelight property. The smaller the value, the better the safelight resistance.

Of the spectral sensitizing dyes of the general formula (I), R ₁ and R
₃ spectral sensitizing dyes such that both ethyl group (I-55, I
In -56), it can be seen that the sensitivity to the red light safelight also increases when a relatively large amount is used.

The same result was obtained by adding the spectral sensitizing dye as a methanol solution instead of adding it as a solid fine particle dispersion. However, as shown in Example 1, the latter method was different from the former method. About 20-30 to get almost the same performance
% Extra addition was required. Therefore, in the latter method, a large amount of the spectral sensitizing dye remains after the development processing, and the deterioration of the image quality due to the coloring stain is remarkable.

Example-3 (Preparation of Em-2) Emulsion-2 was prepared as follows.

6 g of potassium bromide and 7 g of gelatin in 1 liter of water.
37 g of an aqueous silver nitrate solution (4.0 g of silver nitrate) and 38 cc of an aqueous solution containing 5.9 g of potassium bromide were added by a double jet method in 37 seconds into a container kept at 55 ° C. with stirring.
Then, 18.6 g of gelatin was added, the temperature was raised to 70 ° C., and 89 cc of silver nitrate aqueous solution (9.8 g of silver nitrate) was added over 22 minutes.
Here, 7 cc of 25% aqueous ammonia solution was added, and after physically aging for 10 minutes at the same temperature, 6.5 cc of 100% acetic acid solution was added. Subsequently, an aqueous solution of 153 g of silver nitrate and an aqueous solution of potassium bromide were added over 35 minutes by the control double jet method while keeping the pAg at 8.5. Then the potassium thiocyanate solution was added. After physically aging for 5 minutes at the same temperature, the temperature was lowered to 35 ° C. Average projected diameter 1.10 μm, thickness
Monodisperse pure silver bromide tabular grains having a diameter variation coefficient of 0.165 μm and a diameter variation coefficient of 18.5% were obtained. Further, grains having a thickness / twin plane distance ratio of 10 or more contain 50% or more of all grains.

The sensitizing effect obtained by combining the emulsion Em-2 prepared as described above with the spectral sensitizing dye of the general formula (I) and the spectral sensitizing dye of the general formula (II) was examined as follows.

That is, after the emulsion was heated to 60 ° C., the amounts of the spectral sensitizing dyes I-16 and II-2 shown in Table 7 were added as solid fine particle dispersions, and then ammonium thiocyanate, chloroauric acid, and A mixed aqueous solution of sodium thiosulfate and a methanol solution of the following tellurium compound were added, and after 60 minutes, silver iodide fine grain emulsion was added and ripening was carried out for a total of 2 hours. At the end of aging, a proper amount of (TAI) was added as a stabilizer.

[0201]

[Table 7]

The additives and their amounts are as follows.

Potassium thiocyanate 95 mg Chloroauric acid 2.5 mg Sodium thiosulfate 2.0 mg Butyl-diisopropylphosphine telluride 2.0 mg Silver iodide fine particles 850 mg Stabilizer (TAI) 1000 mg The obtained emulsion was treated in the same manner as in Example 2. An emulsion layer coating solution was added. Further, a protective layer coating solution was prepared in exactly the same manner as in Example 2, and both coating solutions were applied and dried in the same manner as in Example 2,
Samples No. 27 to No. 32 were obtained.

Next, these samples were exposed and developed in the same manner as in Example 2.

However, the processing time was adjusted to 30 after adjusting the automatic processor.
Seconds and 45 seconds. The evaluation method was the same as in Example 2. The results obtained are shown in Table 8 below.

[0206]

[Table 8]

As is clear from Table 8, the processing time is 30
It can be seen that even when shortened to seconds, the sample of the present invention has higher sensitivity than the comparative sample and has little change with the processing time.

[0208]

According to the present invention, a silver halide photographic light-sensitive material which achieves high sensitivity and is excellent in storability with time can be obtained. Further, according to the present invention, a silver halide photographic light-sensitive material having less residual color contamination by the residual dye after development processing can be obtained.

Further, the silver halide photographic light-sensitive material using the emulsion of the present invention can obtain the above-mentioned characteristics even if it is processed in a processing step containing a developing solution containing no hardening agent. The effect was even more remarkable.

[Brief description of drawings]

FIG. 1 Spectral spectrum corresponding to the method of adding a spectral sensitizing dye

[Figure 2] Transmittance of red filter

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication G03C 5/26

Claims (5)

[Claims] 1. At least one of the spectral sensitizing dye represented by the following general formula (I) and the spectral sensitizing dye represented by the following general formula (II) is added as solid fine particles, and a reflection spectrum is obtained. Characteristic J-band is formed at 520 to 560 nm, and 50% or more of the development starting point is a peak and /
Alternatively, a silver halide photographic emulsion containing a silver halide having a vicinity of a vertex. [Chemical 1] In the formula, R ₁ and R ₃ represent an alkyl group, R ₂ and R ₄ are lower alkyl groups, and at least one has a hydrophilic group. V ₁ , V ₂ , V ₃ and V ₄ represent a hydrogen atom or a substitutable group in which the sum of Hammett's σ p values added is smaller than 1.7, and at the same time do not become a hydrogen atom or a chlorine atom.
X ₁ represents an ion necessary for neutralizing the charge in the molecule,
n represents 1 or 2. However, n is 1 when forming an intramolecular salt. [Chemical 2] In the formula, R ₅ and R ₆ represent an alkyl group, an alkenyl group or an aryl group, and at least one is a sulfoalkyl group or a carboxyalkyl group. R ₇ represents a hydrogen atom, an alkyl group or an aryl group. Z ₁ and Z ₂ represent a group of non-metal atoms necessary for completing a benzene ring or a naphtho ring. X ₂
Represents an ion necessary for neutralizing the charge in the molecule, and m represents 1 or 2. However, when forming an intramolecular salt, m
Is 1. 2. The silver halide photograph according to claim 1, wherein 70% or more of the total projected area of the silver halide grains contained in the emulsion are tabular silver halide grains having an aspect ratio of 2 or more. Emulsion. 3. The silver halide photographic emulsion according to claim 1, wherein the silver halide grains in the emulsion are chemically sensitized in the presence of a selenium and / or tellurium compound. 4. A silver halide photographic light-sensitive material for medical use, which contains a silver halide photographic emulsion selected from those described in claims 1 to 3. 5. The medical silver halide photograph according to claim 4, wherein the development is carried out with a developer containing substantially no hardening agent, and the total processing time is 15 seconds to 90 seconds. Method of processing photosensitive material.