JPH07175149A - Silver halide photographic emulsion and silver halide photographic sensitive material using same - Google Patents

Abstract

PURPOSE:To obtain the silver halide photographic emulsion having developed silver color tone restrained from becoming yellowish, resistance to occurrence of scratches and fog, high sensitivity, and rapid processing aptitude by specifying an amount of a thiocyanic acid compound present on the surface of silver halide grains. CONSTITUTION:The silver halide grains have an aspect ratio of <2, and >=2 twin crystal faces parallel to each other, and an amount of the thiocyanic acid compound present on the surfaces of the grains is 1.0X10<-3>-4.0X10<-2>mol/mol of silver and as this compound, a thiocyanic metal salt or a water soluble salt such as NH4SCN is used. As its metal salt, preferably, such as, K or Na salt is used, and a hardly soluble salt like AgSCN is added in the form of fine particles, and their preferable diameters are <=0.2mum, especially, <=0.05mum.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a silver halide emulsion having high sensitivity and rapid processing suitability, which has no silver tint of developed silver and is resistant to scratch fog, and a halogen containing the same. The present invention relates to a silver halide photographic light-sensitive material.

[0002]

2. Description of the Related Art In recent years, rapid processing at high temperature has progressed in the field of X-ray photographic light-sensitive materials, and the processing time has been greatly shortened. In order to improve the rapid processing property of the light-sensitive material, for example, improvement of the developability, fixing property and drying property of the silver halide emulsion layer can be mentioned. As one method for accelerating the processability as described above, there is a method of reducing the amount of silver or the amount of binder in the silver halide photosensitive material. However, if the amount of silver is reduced, the sensitivity, gamma, maximum density, etc. will inevitably decrease, and
The decrease in the amount of binder causes deterioration of the physical properties of the film.

Therefore, the development of a light-sensitive material having a high covering power has been promoted conventionally. For example, in recent years, the covering power can be increased by using a tabular silver halide grain having a high aspect ratio and a small grain thickness. For example, U.S. Pat.Nos. 4,11,986, 4,434,226 and 4,413,053
No., etc.

On the other hand, when the content of the binder component is reduced, there is a problem that scratch-like fog is likely to occur during handling of the film or conveyance of the film by rollers. As measures against the scratch fog, for example, JP-A-64-29834 using water-soluble polyesters, JP-A-62-21143 using polyhydroxybenzenes, and further adsorption to silver halide grains Using a specific organic compound having a group
No. 177336 is disclosed.

However, none of these techniques has an insufficient effect of preventing scratch-like fog, and has a problem that the color tone of the silver image after development becomes yellow.

With respect to the silver tone, the tabular grains having a high covering power described above are more remarkable, and have a drawback that the image becomes yellowish. It is known that such silver tone properties almost exclusively depend on the grain size and grain thickness, and fine grain emulsions and tabular emulsions are particularly problematic.

In the light-sensitive material for X-rays, the silver tone is extremely important for the image observer in order to obtain information from this silver image, and a pure black tone and an easy-to-see color tone are desired, and a yellow tint giving an unpleasant impression. Is shunned.

Conventionally, what is called a toning agent is generally used to adjust the color tone of developed silver, and for example, a certain mercapto compound is known. However,
Since the compound has a property of remarkably reducing the sensitivity and developability of a silver halide emulsion, it cannot be used in the present invention aiming at high sensitivity and suitability for rapid processing.

There has been a strong demand for a high-sensitivity and highly rational silver halide photographic light-sensitive material which does not have a yellowish silver tone and is resistant to scratch fog.

[0010]

SUMMARY OF THE INVENTION Accordingly, the object of the present invention is to provide a silver halide emulsion having high sensitivity and rapid processing suitability, which does not have a yellowish tint of developed silver and has scratch fog resistance. It is to provide a silver halide photographic light-sensitive material using the same.

[0011]

The objects of the present invention have been achieved by the following.

(1) The aspect ratio of silver halide grains is 2
Having less than 2 twin planes parallel to each other, and the amount of thiocyanic acid compound present on the surface of the silver halide grain is silver 1.
A silver halide photographic emulsion characterized in that it is 1.0 × 10 ⁻³ mol to 4.0 × 10 ⁻² mol per mol.

(2) A silver halide photographic light-sensitive material having at least one silver halide emulsion layer on a support, wherein the silver halide grains contained in the silver halide emulsion layer are as set forth in claim 1. A silver halide photographic light-sensitive material comprising silver halide grains.

(3) The average silver iodide content of the silver halide grains is less than 1.0 mol% and the average silver iodide content near the outermost surface of the silver halide grains is 1.0 mol% or more. The silver halide photographic emulsion according to claim 1.

(4) A silver halide photographic light-sensitive material having at least one silver halide emulsion layer on a support, wherein the silver halide grains contained in the silver halide emulsion layer are as set forth in claim 3. A silver halide photographic light-sensitive material comprising silver halide grains.

The present invention will be described in detail below.

As the thiocyanic acid compound used in the present invention, a water-soluble salt such as metal thiocyanate or NH ₄ SCN can be used. In the case of a metal salt, a metal element that does not adversely affect photographic performance should be used. Are preferred, and for example, KSCN and NaSCN are preferred.

Further, the sparingly soluble salt such as AgSCN may be added in the form of fine particles.
0.2 μm or less is preferable, and 0.05 μm or less is desirable.

The thiocyan compound may be added at any time during the emulsion production process, but it is preferably added before the desalting process and before the end of chemical ripening (sensitization).

The amount of addition is chemical ripening (sensitization) from the time of grain formation.
The total amount added up to the end is 1. per mol of silver halide.
^{0x10 -3} mol or more and ^{4x10 -2} mol or less, preferably 1.2x10
^-3 mol or more and 4.0 x 10 ^-2 mol or less, and even if removed in the desalting step of the emulsion, the amount finally present on the surface of the silver halide grain is 1.0 x 10 per mol of silver halide.
^-3 mol or more and 4 x 10 ^-2 mol or less, particularly 1.3 x 10 ^-3 mol or more and 3.5 x 10 ^-2 mol or less are preferably present. The thiocyanic acid compound, which is added during the chemical sensitization, may be used as a ligand for the gold sensitizer.

The present invention can achieve the intended effect of the present invention by controlling the amount of the thiocyanic acid compound present on the surface of the silver halide grain, and the desired amount of thiocyanate is present on the surface of the silver halide grain. Need to know if they are doing.

The method for quantifying the thiocyanic acid compound contained in the emulsion of the light-sensitive material will be described below. (Actually refer to the examples) Determination of thiocyanate ion in emulsion before coating To an emulsion containing 1.5 × 10 ^-2 mol of silver halide, 10 cc of 1% KBr aqueous solution was added and stirred at 40 ° C. for 30 minutes. The emulsion was centrifuged to completely separate the emulsion, and the supernatant was diluted 100 times. Further, the diluted solution was subjected to ultrafiltration, and then thiocyanate ion in the diluted solution was quantified by ion chromatography. For the quantification, a calibration curve prepared separately using an aqueous solution of thiocyanate compound was used.

2. Determination of thiocyanate ion on the surface of silver halide grains in emulsion before coating 10 cc of distilled water to an emulsion containing 1.5 × 10 ^-2 mol of silver halide
The mixture was stirred at 40 ° C for 30 minutes. The emulsion was centrifuged to completely separate the emulsion, and the supernatant was diluted 100 times. Further, the diluted solution was subjected to ultrafiltration, and then thiocyanate ion in the diluted solution was quantified by ion chromatography. For the quantification, a calibration curve prepared separately using an aqueous solution of thiocyanate compound was used.

The amount of thiocyanate ions on the target grain surface was determined by subtracting the value thus obtained from the value of all thiocyanate ions in the emulsion previously obtained.

3. Quantitative determination of thiocyanate ion in the light-sensitive material in the product state 49cc after peeling off the emulsion layer containing 0.1g of silver from the light-sensitive material
Soak in distilled water. 1 cc of 5% KBr solution in this solution
After addition, ultrasonically stir at 40 ° C for 30 minutes. The solution is centrifuged and the supernatant is filtered. The filtered supernatant is diluted 10-fold and then the thiocyanate ion contained therein is quantified by ionon chromatography. For the quantification, a calibration curve prepared separately using an aqueous solution of thiocyanate compound was used.

4. Quantification of thiocyanate ion on the surface of silver halide grains in the light-sensitive material in a product state. 50 cc of the emulsion layer containing 0.1 g of silver was peeled off from the light-sensitive material.
Soak in distilled water.

The solution is ultrasonically stirred at 40 ° C. for 30 minutes. The solution is centrifuged and the supernatant is filtered.
The filtered supernatant is diluted 10-fold and then the thiocyanate ion contained therein is quantified by ion chromatography. The value thus obtained was subtracted from the previously obtained value of thiocyanate ion in the light-sensitive material to obtain the amount of thiocyanate ion on the target grain surface. Even in the case of a multi-layered product, the amount of thiocyanate ions in the target layer can be known by performing peeling for each layer.

The silver halide grain of the present invention is a twin grain having two or more twin planes parallel to each other, preferably an even number, and more preferably two twin planes.

Twin grains refer to silver halide grains having one or more twin planes, and the morphology of twins is classified by Klein and Moiser in the report “Photographische Korrespo”.
ndenz ”99 volumes 99 pages, 100 volumes 57 pages.
In the present invention, the number of twin grains having two or more twin planes parallel to each other according to the present invention, when counted from large grains, is 50% or more, preferably 60% or more, and more preferably 70% or more. % Or more.

The twin according to the present invention may be composed of (111) plane, (100) plane, or both.

The shape of the silver halide grains according to the present invention is
It may have a regular crystal form such as a cube, an octahedron, or a tetrahedron, or an irregular crystal form such as a sphere, a plate, or a potato, and may be a mixed type or a composite type thereof. May be.

The silver halide grains according to the present invention have an average value of grain diameter / thickness (referred to as aspect ratio) (referred to as average aspect ratio) of less than 2, preferably less than 1.6.

The emulsion used in the silver halide photographic light-sensitive material of the present invention can be produced by a known method. For example, Research Disclosure (RD) No.17643 (December 1978), 22
Can be prepared by referring to the method described in "Emulsion Preparation and Types" on page 23, or the method described in (RD) No. 18716 (November 1979), page 648.

The emulsion used in the silver halide photographic light-sensitive material of the present invention is described, for example, in "The Theory of the" by TH James.
Photographic process ”4th edition, published by Macmillan (1977
Year) Method described on pages 38-104, GF Duffin, “Photograph
ic Emulsion Chemistry ”, published by Focal Press (1966),
“Chimie et Physique Photographique” by P. Glafkides
Published by Paul Montel (1967) or VL Zelikman et al. “Makin
g And Coting Photographic Emulsion "Focal Press, Inc. (1964).

That is, the mixing conditions such as the forward mixing method, the reverse mixing method, the double jet method and the control double jet method under the solution conditions such as the acidic method, the ammonia method and the neutral method,
It can be produced using a particle preparation condition such as a conversion method, a core / shell method, or a combination thereof.

A preferred embodiment of the emulsion used in the silver halide photographic light-sensitive material of the present invention is a monodisperse emulsion in which silver iodide is localized inside the grains.

The monodisperse as used herein means at least 95 in terms of the number of particles or the weight when the average particle diameter is measured by a conventional method.
% Particles are within ± 30% of the average particle size, preferably ± 20%
It is within the range of silver halide grains. The monodispersity referred to here is defined in JP-A-60-162244, and the coefficient of variation with respect to particle diameter is 0.20 or less.

The crystal structure of silver halide may be composed of different silver halide compositions inside and outside. That is, it has a core / shell structure composed of a core and at least one shell having different halogen compositions. The silver iodide content in the high iodine portion is 5 to 40 mol%, particularly preferably 5 to 30 mol%.

A method for producing such a monodisperse emulsion is known, for example, J. Phot. Sci, 12.242 to 251, (1963), JP-A-48-36890.
Nos. 52-16364, 55-142329, 58-49938, British Patent 1,413,748, U.S. Patents 3,574,628, 3,655,39.
It is described in detail in No. 4 etc.

As a method for obtaining the above-mentioned monodisperse emulsion, for example, a method of using a seed crystal, and using this seed crystal as a growth nucleus to supply silver ions and halide ions to grow, is particularly preferable.

A method for producing a core / shell type emulsion is well known, for example, British Patent No. 1,027,146 and US Pat. No. 3,505,068.
No. 4,444,877 or JP-A-60-143331 can be referred to.

The silver halide emulsion according to the present invention has any halogen composition such as silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodobromide, silver chloroiodobromide, etc. Silver iodobromide is preferable from the viewpoints of the property and high sensitivity, and the average silver iodide content is
It is less than 1.0 mol%, particularly preferably less than 0.6 mol%.

The average silver iodide content in the vicinity of the outermost surface of the silver halide grain according to the present invention is 1.0 mol% or more, preferably 1.5 mol% or more. The average silver iodide content (rate) referred to herein is the standard deviation of the silver iodide content when the silver iodide content of at least 100 emulsion grains is measured, divided by the average silver iodide content. It is the value obtained by multiplying the value by 100.

Incidentally, the Journal of the Photographic Society of Japan, Vol. 53, No. 2, 125-1
On page 28 (1990), the results of measuring the silver iodide content for each internal structure of each silver halide grain by an analytical electron microscope are reported. See also Journal of imaging scien
ce vol.31.No.1 (1987) .Pages 15-26 show the intragranular fine structure of the tabular grains in terms of halogen composition.
-Temperature eluminescence microscopy) has been reported. Further Journal of imagi
ng science Vol.32.No.4 (1988). Pages 160-177 show that silver iodide deposits when silver chloride is precipitated on silver iodobromide which has a silver iodide distribution within the grain. It is reported that the place is decided (site direct).

Furthermore, the journal of the Photographic Society of Japan, Volume 35 (1990), No. 21
From page 3, it is reported that non-uniformity of the halogen composition in the grains can be observed by directly observing the grains at low temperature using a transmission electron microscope. In this way, the fine structure of the silver halide composition of each silver halide grain can be observed.

In the present invention, the vicinity of the outermost surface of the silver halide grain means that when the average silver iodide content on the surface of the silver halide grain is measured by the XPS method in the silver halide grain, X-rays are silver halide grains. It refers to the silver halide phase existing in the area that enters and reaches from the surface, and usually about 50 of the outermost layers constituting the silver halide grains, including the grain surface.
Corresponds to the area of Å. The average silver iodide content in the vicinity of the outermost surface of the silver halide grain in the present invention is a value measured by the XPS method in a state where a sample prepared from the silver halide grain is cooled to -110 ° C or lower.

Prior to the XPS method, the silver halide emulsion is pretreated as follows. First, a 0.05% by weight aqueous solution of proteolytic enzyme (pronase) is added, and gelatin is decomposed by stirring at 45 ° C for 30 minutes. Next, the silver halide grains are settled by centrifugation and the supernatant liquid is removed. Then, distilled water is added to disperse the silver halide grains in distilled water, and the mixture is centrifuged to remove the supernatant liquid. Then, the silver halide grains are separated again in distilled water. This is thinly applied onto a mirror-polished silicon wafer to obtain a measurement sample.

Using the sample thus prepared, XP
The average silver iodide content in the vicinity of the outermost surface of the silver halide grain is measured by S. In order to prevent the sample from being destroyed by the above-mentioned X-ray irradiation, the sample is cooled from −110 ° C. to −120 ° C. using liquid nitrogen or liquid helium in the XPS measurement chamber. As the probe X-ray, the Mg-K line is used as the X-ray source voltage 15
Irradiate with KV and X-ray source current of 40mA.

Ag ₃ d, Br ₃ d, and I ₃ d 3/2 electrons are detected to determine the halide composition near the surface of the silver halide grain. The composition ratio is calculated by using the integrated intensity of each measured peak as the sensitivity factor.
The average silver iodide content in the vicinity of the outermost surface of the silver halide is measured from the intensity ratio after correction with (Sensitivity Factor).

50 mol% or more of the total amount of silver iodide in the silver halide emulsion according to the present invention is due to the supply of fine grain silver iodide, preferably 70 mol% or more, more preferably 90 mol% or more. is there. Since the grain size of fine grain silver iodide controls the supply rate of iodide ions, the preferable grain size varies depending on the grain size and halogen composition of the silver halide grain serving as a host, but the average spherical equivalent diameter is 0.1 μm or less. Is preferred.

Further, in order for the fine grain silver iodide to form a solid solution in the host grain according to the present invention to be recrystallized, the grain size of the fine grain silver iodide is preferably smaller than the equivalent spherical diameter of the host grain. With respect to silver iodide, generally cubic γ-AgI and hexagonal β-AgI are known, but any crystal structure of fine grain silver iodide used in the present invention is not known. Or a mixture thereof.

The fine grain silver iodide used in the present invention preferably has good monodispersibility, and is preferably prepared by the double jet method while controlling the temperature, pH and pAg.

The method for producing a twinned emulsion having two or more twin planes parallel to each other according to the present invention is as follows: a silver nitrate aqueous solution is added to a gelatin aqueous solution having a pBr of 3.0 or less, or a silver nitrate aqueous solution and a halide are added. It can be obtained by adding an aqueous solution at the same time to generate twinned seed particles and then growing by twin jet method. The size of silver halide grains can be controlled by the temperature at the time of grain formation and the addition rate of silver salt and halide aqueous solution.

The average silver iodide content and the average silver chloride content of the silver halide emulsion according to the present invention are the compositions of the silver halide fine grain emulsion and / or halide aqueous solution to be added, that is, bromide, iodide and chloride. It can be controlled by changing the ratio. Also, when manufacturing the emulsion,
If necessary, a silver halide solvent such as ammonia, thioether or thiourea can be used.

The emulsion may be subjected to a water washing method such as a noodle water washing method or a flocculation sedimentation method in order to remove soluble salts (desalting treatment step). A preferred washing method is, for example, a method using an aromatic hydrocarbon aldehyde resin containing a sulfo group described in JP-B-35-16086, or JP
A particularly preferable desalting method is a method using G3, G8 and the like, which are the aggregation polymer agents described in 63-158644.

The silver halide emulsion of the present invention is chemically ripened. The chemical ripening temperature of the emulsion according to the present invention can be arbitrarily determined, but is preferably in the range of 20 ° C to 90 ° C, preferably 30
C. to 80.degree. C., more preferably 35.degree. C. to 70.degree. The silver halide emulsion of the present invention is preferably combined with chalcogen sensitization and gold sensitization as sensitizing methods. Particularly, the combined use of gold sensitization and sulfur sensitization is preferable because not only the sensitizing effect is remarkable but also the fog suppressing effect is obtained.

For sulfur sensitization, sensitizers such as thiosulfate, allylthiocarbamidothiourea, allylisothiocyanate, cystine, p-toluenethiosulfonate, and rhodanine can be used. Other U.S. Patents 1,574,944
No. 3,656,955, German Patent 1,422,869, Japanese Patent Sho 56
The sulfur sensitizers described in JP-A-24937 and JP-A-55-45016 can also be used. The sulfur sensitizer may be added in an amount sufficient to effectively increase the sensitivity of the emulsion. This amount can be varied over a wide range under various conditions such as pH, temperature and size of silver halide grains, but as a guide, it is 5 × 10 ^{−8 to} 5 × per mol of silver halide of the emulsion according to the present invention.
10 ^-5 mol is preferred.

For gold sensitization, gold sensitizers such as chloroauric acid salt, gold thiourea complex salt, potassium chloroaurate, auric trichloride, potassium auric thiocyanate, potassium iodoaurate, tetracyanoauric amide, ammonium auro are used. Examples thereof include thiocyanate and pyridyl trichlorogold. The addition amount of these gold sensitizers can be varied over a wide range under various conditions, but as a guide, it is preferably 5 × 10 ^{−7 to} 5 × 10 ⁻³ mol per mol of silver halide of the emulsion of the present invention, and 2 X 10 ^-6 to 4 x
More preferably 10 ⁻⁴ mol.

In the present invention, reduction sensitization and hydrogen sensitization methods can be used. As the reduction sensitizer, stannous salt, amines, formamine disulfinic acid, silane compound, borane compound, ascorbic acid and its derivatives can be used.

The amount of the reduction sensitizer added depends on the reducing property of the compound,
Although not uniform depending on the type of silver halide and the dissolution conditions, the range of 1 × 10 ⁻⁸ to 1 × 10 ⁻² mol per mol of silver halide is suitable. The reduction sensitizer is added after being dissolved in water or a solvent such as alcohol, glycol, ketone, ester, amide and the like. The reduction sensitization can be carried out at the time of forming silver halide grains. The term "during grain formation" means any one of a nucleation step, a ripening step, and a growth step.

As a method of performing reduction sensitization at the time of grain formation, a method of forming a silver halide grain by adding a water-soluble silver salt and an aqueous halide solution, and adding a reduction sensitizer to the aqueous halide solution in advance. Or a method in which the reduction sensitizer is added in a state where the growth is temporarily stopped and then further grown, and a method in which the reduction sensitizer is added in several times as the particles grow. . In addition to the method of using a known reduction sensitizer, a method of growing or aging in a pHAg atmosphere called silver ripening, a method of growing or aging in a high pH atmosphere, for example, pH 8 to 11, should be selected. It is also possible to use these in combination.

Further, in the present invention, tellurium sensitization can be used, but when tellurium sensitization is used, it is preferably used in combination with another sensitizing method. Examples of the tellurium sensitizer used in the present invention include U.S. Pat.No. 3,772,031, British Patent 235,211, Canadian Patent 800,958, and J. Chem. Soc. Chem.
Commun .; 635 (1980), ibid 1102 (1979), ibid 645 (1
979), J. Chem. Soc. Perkin Trans .; 1, 2191 (198) and the like are preferably used.

Specific tellurium sensitizers include colloidal tellurium and telluroureas (eg, allyl tellurourea, N,
N-dimethyl tellurourea, tetramethyl tellurourea, N-carboxyethyl-N ', N'-dimethyl tellurourea, N, N'-
Dimethyl ethylene tellurourea, N, N'-diphenyl ethylene tellurourea), isotellocyanates (eg allyl isotellurocyanate), telluroketones (eg telluroacetone, telluroacetophenone), telluroamides (eg telluroacetamide, N, N- Dimethyl tellurobenzamide), tellurohydrazide (for example N, N ′, N′-trimethyltelulobenzhydrazide), telluroester (for example t-butyl-t-hexyltelluroester), phosphine tellurides (for example tributylphosphine telluride, tritium) Cyclohexylphosphine telluride, triisopropylphosphine telluride, butyl-diisopropylphosphine telluride, dibutylphenylphosphine telluride), other tellurium compounds (eg British Patent 1,295,462)
Examples thereof include negatively charged telluride ion-containing gelatin, potassium telluride, potassium tellurocyanate, telluropentathionate sodium salt, and allyl tellurocyanate).

Of these tellurium compounds, preferred are the compounds represented by the following general formulas (I) and (II).

[0065]

[Chemical 1]

In the formula, R ₁₁ , R ₁₂ and R ₁₃ are aliphatic groups,
Aromatic group, heterocyclic group, OR ₁₄ , NR ₁₅ (R ₁₆ ), SR ₁₇ , OSiR
_{It represents 18} (R ₁₉ ) (R ₂₀ ), X or a hydrogen atom. R ₁₄ and R
₁₇ represents an aliphatic group, an aromatic group, a heterocyclic group, a hydrogen atom or a cation, R ₁₅ and R ₁₆ are an aliphatic group, an aromatic group,
Represents a heterocyclic group or a hydrogen atom, R ₁₈ , R ₁₉ and R
₂₀ represents an aliphatic group, and X represents a halogen atom.

Next, the general formula (I) will be described in detail. In the general formula (I), R ₁₁ , R ₁₂ , R ₁₃ , R ₁₄ ,
The aliphatic group represented by _{R 15, R 16, R 17} , R 18, R 19 and R ₂₀ are preferably be those having 1 to 30 carbon atoms, especially straight-chain having 1 to 20 carbon atoms, branched or It is a cyclic alkyl group, alkenyl group, alkynyl group or aralkyl group. Examples of the alkyl group, alkenyl group, alkyl group and aralkyl group include methyl, ethyl, n-propyl, isopropyl, t-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopentyl, cyclohexyl, allyl, butenyl, 3 -Pentenyl, propargyl, 3-pentynyl, benzyl, phenethyl. In the general formula (I), the aromatic groups represented by R ₁₁ , R ₁₂ , R ₁₃ , R ₁₄ , R ₁₅ , R ₁₆ and R ₁₇ are preferably those having 6 to 30 carbon atoms, and particularly preferably carbon atoms. It is a monocyclic or condensed ring aryl group of the number 6 to 20, and examples thereof include phenyl and naphthyl.

In the general formula (I), R ₁₁ , R ₁₂ ,
The heterocyclic group represented by R ₁₃ , R ₁₄ , R ₁₅ , R ₁₆ and R ₁₇ is a 3- to 10-membered saturated or unsaturated heterocyclic ring containing at least one of a nitrogen atom, an oxygen atom and a sulfur atom. It is a base. These may be a single ring or may form a condensed ring with another aromatic ring or a heterocycle. The heterocyclic group is preferably a 5- or 6-membered aromatic heterocyclic group, and examples thereof include pyridyl, furyl, thienyl, thiazolyl, imidazolyl and benzimidazolyl.
In the general formula (I), the cation represented by R ₁₄ and R ₁₇ represents, for example, an alkali metal or ammonium. The halogen atom represented by X in the general formula (I) represents, for example, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Further, the aliphatic group, aromatic group and heterocyclic group may be substituted. The following are mentioned as a substituent. Representative substituents include, for example, alkyl groups,
Aralkyl, alkenyl, alkynyl, aryl, alkoxy, aryloxy, amino, acylamino, ureido, urethane, sulfonylamino, sulfamoyl, carbamoyl, sulfonyl, sulfinyl, alkyloxycarbonyl Group, aryloxycarbonyl group, acyl group, acyloxy group, phosphoric acid amide group, diacylamino group, imide group, alkylthio group, arylthio group, halogen atom, cyano group, sulfo group, carboxy group, hydroxy group, phosphono group, nitro Groups, and heterocyclic groups. These groups may be further substituted. When there are two or more substituents, they may be the same or different.

R ₁₁ , R ₁₂ and R ₁₃ may be bonded to each other to form a ring together with the phosphorus atom, and R ₁₅ and R ₁₆ may be bonded to form a nitrogen-containing heterocycle. . General formula (I)
Of these, preferably R ₁₁ , R ₁₂ and R ₁₃ represent an aliphatic group or an aromatic group, more preferably an alkyl group or an aromatic group.

Next, the general formula (II) will be described in detail.

[0071]

[Chemical 2]

In the formula, R ₂₁ represents an aliphatic group, an aromatic group, a heterocyclic group or -NR ₂₃ (R ₂₄ ), and R ₂₂ represents -NR ₂₅ (R ₂₆ ), -N.
It represents the _{(R 27) -N (R 28} ) R 29 or -OR _30. R ₂₃ , R ₂₄ , R
₂₅ , R ₂₆ , R ₂₇ , R ₂₈ , R ₂₉ and R ₃₀ represent a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group or an acyl group. Where R ₂₁ and R ₂₅ , R ₂₁ and R ₂₇ , R ₂₁ and R ₂₈ , R ₂₁ and R ₃₀ , R ₂₃ and R ₂₅ , R ₂₃ and R ₂₇ , R ₂₃ and R _28, and R ₂₃
And R ₃₀ may combine to form a ring.

In the general formula (II), R ₂₁ , R ₂₃ ,
The aliphatic group represented by R ₂₄ , R ₂₅ , R ₂₆ , R ₂₇ , R ₂₈ , R ₂₉ and R ₃₀ is preferably one having 1 to 30 carbon atoms, and particularly a straight chain having 1 to 20 carbon atoms. A branched or cyclic alkyl group, alkenyl group, alkynyl group and aralkyl group. Examples of the alkyl group, alkenyl group, alkynyl group and aralkyl group include methyl, ethyl, n-propyl,
Examples include isopropyl, t-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopentyl, cyclohexyl, allyl, 2-butenyl, 3-pentenyl, propargyl, 3-pentynyl, benzyl and phenethyl. In the general formula (II), R ₂₁ , R ₂₃ , R ₂₄ , R ₂₅ , R ₂₆ ,
The aromatic group represented by R ₂₇ , R ₂₈ , R ₂₉ and R ₃₀ preferably has 6 to 30 carbon atoms, particularly 6 to 20 carbon atoms.
Is a monocyclic or condensed ring aryl group, and examples thereof include phenyl and naphthyl.

In the general formula (II), R ₂₁ , R ₂₃ ,
The heterocyclic group represented by R ₂₄ , R ₂₅ , R ₂₆ , R ₂₇ , R ₂₈ , R ₂₉ and R ₃₀ is a saturated 3- to 10-membered ring containing at least one of a nitrogen atom, an oxygen atom and a sulfur atom. Alternatively, it is an unsaturated heterocyclic group. These may be monocyclic,
Further, a condensed ring may be formed with another aromatic ring or hetero ring. The heterocyclic group is preferably a 5- or 6-membered aromatic heterocyclic group, and examples thereof include pyridyl, furyl, thiethyl, thiazolyl, imidazolyl and benzimidazolyl. In the general formula (II), R ₂₃ , R ₂₄ ,
The acyl group represented by R ₂₅ , R ₂₆ , R ₂₇ , R ₂₈ , R ₂₉ and R ₃₀ is preferably one having 1 to 30 carbon atoms, and particularly a straight chain or branched acyl group having 1 to 20 carbon atoms. The group is, for example, acetyl, benzoyl, formyl, pivaloyl, decanoyl. Where R ₂₁ and R ₂₅ , R ₂₁ and R ₂₇ ,
R ₂₁ and R ₂₈ , R ₂₁ and R ₃₀ , R ₂₃ and R ₂₅ , R ₂₃ and R ₂₇ , R
_{When 23} and R ₂₈ and R ₂₃ and R ₃₀ combine to form a ring, examples thereof include an alkylene group, an arylene group, an aralkyl group and an alkenylene group.

Further, the aliphatic group, aromatic group and heterocyclic group may be substituted with the substituents mentioned in the general formula (I). In the general formula (II), preferably R ₂₁ represents an aliphatic group, an aromatic group or —NR ₂₃ (R ₂₄ ), and R ₂₂ represents —NR ₂₅ (R ₂₆ ).
Represents R ₂₃ , R ₂₄ , R ₂₅ and R ₂₆ represent an aliphatic group or an aromatic group. In formula (II), more preferably R ₂₁
Represents an aromatic group or -NR ₂₃ (R ₂₄ ), and R ₂₂ represents -NR ₂₅ (R
₂₆ ). R ₂₃ , R ₂₄ , R ₂₅ and R ₂₆ represent an alkyl group or an aromatic group. Where R ₂₁ and R ₂₅ and R ₂₃
More preferably, R ₂₅ and R ₂₅ form a ring via an alkylene group, an arylene group, an aralkylene group or an alkenylene group.

Specific examples (exemplary compounds) of the compounds represented by formulas (I) and (II) are shown below.

[0077]

[Chemical 3]

[0078]

[Chemical 4]

[0079]

[Chemical 5]

[0080]

[Chemical 6]

The compounds represented by the general formulas (I) and (II) can be synthesized according to already known methods. For example, J. Chem. Soc. (A); 1969, 2927; J. Organome.C
hem .; 4,320 (1965); ibid. 1,200 (1963); ibid. 113.
C35 (1976); Phosphorus Sulfur; 15,155 (1983); Che
m.Ber.; 109, 2996 (1976); J.Chem.Soc.Chem.Commu
n .; 635 (1980); ibid. 1102 (1976); ibid. 645 (197
9); ibid. 820 (1987); J. Chem. Soc. Perkin. Trans .; 1,
2191 (1980); The Chemistry of Organo Seleniumand
Tellurium Compounds; can be synthesized by the method described in Volume 2 216 to 267 (1987).

The amount of these tellurium sensitizers used in the present invention varies depending on the silver halide grains used, the chemical ripening conditions and the like, but is generally from 10 ^-8 to 1 mol per mol of silver halide.
10 ⁻² mol, preferably about 10 ^{−7 to} 5 × 10 ⁻³ mol is used. The conditions for chemical sensitization in the present invention are not particularly limited, but pAg is 6 to 11, preferably 7 to 10, and temperature is 40 to 95 ° C, preferably 45 to 85 ° C.

The silver halide emulsion of the present invention can be spectrally sensitized.

As the spectral sensitizing dye used in the present invention, a methine dye is usually used.
Examples include merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes and hemioxonol dyes.

Examples thereof include oxacarbocyanine, benzimidazolocarbocyanine, and benzimidazolo-oxacarbocyanine as described in Japanese Patent Application No. 3-95310. Further, dyes having a sensitizing effect in the blue light region described in Japanese Patent Application No. 5-121484 are also preferably used. These spectral sensitizing dyes can be used alone or in combination.

The spectral sensitizing dye is preferably added as a solution dissolved in an organic solvent such as methanol.

The addition amount of the spectral sensitizing dye is not uniform depending on the kind of the dye and the emulsion conditions, but it is 10 per 1 mol of silver in the emulsion.
mg to 900 mg is preferred, and 60 mg to 400 mg is particularly preferred.

The spectral sensitizing dye is preferably added before the end of the chemical ripening step, and may be added in several batches before the end of the chemical ripening step. More preferably, it is after the growth step of silver halide grains and before the end of the chemical ripening step, and particularly preferably before the start of chemical ripening.

In the present invention, in order to stop the chemical sensitization (chemical ripening), a method using a chemical ripening stopper is preferable in consideration of the stability of the emulsion. Examples of the chemical aging inhibitor include halides (eg, potassium bromide, sodium chloride, etc.), organic compounds known as antifoggants or stabilizers (eg, 4-hydroxy-6-methyl-1,3,3a, 7).
-Tetrazaindene etc.). These may be used alone or in combination of two or more compounds.

The emulsion according to the present invention can use various photographic additives in the steps before and after physical ripening or chemical ripening. Known additives include, for example, Research Disclosure (RD) No. 17643 (December 1978),
No. 18716 (November 1979) and No. 308119 (December 1989)
Month). The types of compounds and the places where they are described in these three Research Disclosures are listed below.

Additive RD-17643 RD-18716 RD-308119 Page Classification Page Classification Page Classification Chemical sensitizer 23 III 648 Upper right 996 III Sensitizing dye 23 IV 648-649 996-8 IVA Desensitizing dye 23 IV 998 VB 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 Hardener 26 X 651 Left 1004-5 X Surfactant Agent 26-7 XI 650 Right 1005-6 XI Antistatic agent 27 XII 650 Right 1006-7 XIII Plasticizer 27 XII 650 Right 1006 XII Sliding agent 27 XII Matting agent 28 XVI 650 Right 1008-9 XVI Binder 26 XXII 1003-4 IX Support 28 XVII 1009 XVII Supports that can be used in the light-sensitive material of the present invention include, for example, RD-17643, page 28 and RD-308119, 100.
Examples include those described on page 9.

A suitable support is a polyethylene terephthalate 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.

[0093]

EXAMPLES Examples of the present invention will be described below. However, as a matter of course, the present invention is not limited to the examples described below.

Example 1 <Preparation of seed emulsion A> A seed emulsion A made of silver bromide was prepared using the following solution.

[0095] A ₁ Hydrogen peroxide treated ossein gelatin 40g Potassium bromide _{75.1g HO (CH 2 CH 2 O} ) m- (CH (CH 3) CH 2 O) 17 - (CH 2 CH 2 O) nH ( m + n≈5.7) 10% methanol solution 10 ml Water added 400 ml B ₁ silver nitrate 600 g water added 803 ml C ₁ hydrogen peroxide treated ossein gelatin 16.1 g potassium bromide 420 g water added 803 ml D ₁ ammonia Water (28%) 235 ml Using the device disclosed in Japanese Patent Laid-Open No. 62-160128, the number of supply nozzles to the lower part of the mixing stirring impeller is 6 for each of solution B ₁ and solution C ₁ . Installed.

Solution B ₁ and solution C ₁ were added at a flow rate of 62.8 ml / min by the controlled double jet method to solution A ₁ which was rapidly stirred at a temperature of 40 ° C. and a rotation speed of 430 rpm. The flow rate was gradually increased from 4 minutes and 46 seconds after the start of the addition so that the final flow rate was 105 ml / min. Total addition time is 10 minutes
It was 45 seconds. With potassium bromide solution (3.5N), adding
The pBr was kept at 1.3.

After the addition was completed, the temperature of the mixed solution was increased to 20 minutes within 105 minutes.
Solution D
₁ was added for 20 seconds and Ostwald ripening was carried out for 5 minutes. During aging, the bromine ion concentration was 0.025 mol / l, the ammonia concentration was 0.63 mol / l, and the pH was 11.7.

Immediately thereafter, acetic acid was added to neutralize the pH to 5.6 to stop ripening, and in order to remove excess salts, desalting was performed using an aqueous solution of Demol N (manufactured by Kao Atlas) and an aqueous solution of magnesium sulfate. It was washed with water to obtain a seed emulsion A. When the seed emulsion A was observed with an electron microscope, it was found to be spherical grains having an average grain size of 0.24 μm and a grain size variation coefficient of 17%.

(Preparation of fine grain silver iodide emulsion) 5000 ml of a 5.2% by weight gelatin solution containing 0.008 mol of potassium iodide,
An aqueous solution containing 1.06 mol of silver nitrate and potassium iodide was added at a constant flow rate of 1500 ml over 35 minutes. During this time, the temperature was kept at 40 ° C. The obtained silver iodide fine particles had an average particle diameter of 0.043 μm and was a mixture of β-AgI and γ-AgI.

Subsequently, the seed emulsion A was used to prepare an emulsion mainly composed of tabular twin crystals according to the present invention.

[0102] <Emulsion EM-1 of Preparation> A2 ossein gelatin 42.8 g HO- [CH ₂ CH ₂ O] _m - [CH (CH ₃₎ -CH ₂ O] ₁₇ - [CH ₂ CH ₂ O] _n - OH ( _m + _n ≈5.7) MW1700 (10% methanol solution) 9.0ml 28wt% ammonia solution 370ml 56wt% acetic acid solution 530ml Pure water to 3700ml B2 ossein gelatin 24.0g potassium bromide 2430g pure water 4800ml C2 Silver nitrate 3530g 28% Ammonia aqueous solution 2880ml Ammonium nitrate 668g Pure water 5940ml D2 fine grain silver iodide emulsion 0.298mol E2 seed emulsion A 0.83mol equivalent F2 3.5N potassium bromide aqueous solution pAg control G2 56% by weight acetic acid aqueous solution pH control liquid temperature The seed emulsion A was put into the solution A2 which was vigorously stirred at 75 ° C., and the seed emulsion A was well dispersed, and the solution B2, the solution C2, and the solution D2 were added by the controlled double jet method in 197 minutes.

Addition of D2 was completed when 8% of B2 was added.

Here, the addition rates of the B2, C2, and D2 solutions were changed in a function-like manner with respect to time so as to be commensurate with the critical growth rate, and small particles other than the growing seed crystal were generated and Ostwald ripening was performed. It was added at an appropriate addition rate so as not to cause polydispersion.

Solution D2, that is, fine grain silver iodide was supplied by B
A core / shell type silver halide emulsion having a multiple structure was prepared by setting the rate ratio (molar ratio) of the two liquids, that is, the aqueous solution of ammoniacal silver nitrate to 0.33, and changing it with respect to the grain size (addition time).

By using E2 liquid and F2 liquid,
During the grain growth, pAg was kept at 8.00 and pH was kept at 7.0. Immediately after the addition was completed, the pH was adjusted to 6.0 with acetic acid, and in order to remove excess salts, an aqueous solution of demol N (an aldehyde condensate of naphthalene sulfonic acid sodium salt) manufactured by Kao Atlas Co., Ltd. and magnesium sulfate was used. After desalting, gelatin was added and redispersed at 40 ° C. under the conditions of pH = 8.5 and pH = 5.85 to obtain Emulsion EM-1. Observed with a scanning electron microscope, one side with two parallel twin planes is 0.
It was a cubic particle of 97 μm.

<Preparation of Emulsion EM-2> In the preparation method of Emulsion EM-1, 108 minutes after the addition of the C2 solution (completion of 80% of the total amount of silver added), a constant flow rate of 1800 ml of 4.37N potassium bromide aqueous solution was established. Over 8 minutes. Em-2 was prepared in exactly the same manner as EM-1, except that this aqueous solution of potassium bromide was added. The obtained emulsion is about 200 with a scanning electron microscope.
When the sample was observed, the apex of the cube was rounded with an average particle size of 0.98 μm. Also, as in EM-1, two twin planes parallel to each other were observed.

[0107] <Preparation of Seed Emulsion B> A3 ossein gelatin 24.2g Distilled water _{9657ml HO- (CH 2 CH 2 O} ) n- [CH (CH 3) CH 2 O] 17 - (CH 2 CH 2 O) m H ( _n + _m = 5.7 average molecular weight 1700) 10% methanol aqueous solution 6.78ml KBr 10.8g 10% nitric acid 114ml B3 2.5N silver nitrate aqueous solution 2825ml C3 KBr 824g KI 23.5g distilled water 2825ml D3 1.75N KBr aqueous solution Using a mixing stirrer described in JP-B-58-58288 and JP-B-58-58289 at a controlled amount of 35 ° C., solution B3 and solution C were added to solution A3.
Nucleation was carried out by adding 464.3 ml of each of 3 by the simultaneous mixing method over 2 minutes.

After the addition of the solutions B3 and C3 was stopped, it took 60 minutes to raise the temperature of the solution A3 to 60 ° C., and the solutions B3 and C3 were mixed again by the simultaneous mixing method to give 5
It was added for 42 minutes at a flow rate of 5.4 ml / min. This 35 ℃ to 60 ℃
Control the silver potential (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) during temperature rise to and re-simultaneous mixing with solutions B3 and C3 to be +5 mV and +12 mV, respectively, using solution D3. did.

After completion of the addition, the pH was adjusted to 6.0 with 3% KOH, and the mixture was immediately desalted and washed with water to obtain seed emulsion B. In this seed emulsion B, 90% or more of the total projected area of silver halide grains consisted of hexagonal tabular grains having a maximum adjacent side ratio of 1.0 to 2.0. The hexagonal tabular plate had an average thickness of 0.05 μm and an average diameter (circular diameter conversion). Is 0.55 μm
It was proved by electron microscope observation.

[0110] <Preparation of Emulsion EM-3> A4 ossein gelatin _{40.5g HO- (CH 2 CH 2 O} ) n - [CH (CH 3) CH 2 O] 17 - (CH 2 CH 2 O) mH (n + _m = 5.7 average molecular weight about 1700) 10% methanol aqueous solution 9.0 ml distilled water to 3700 ml B4 ossein gelatin 30.0 g KBr 2500 g distilled water to 6000 ml C4 silver nitrate 3500 g distilled water to 5900 ml D4 fine grain silver iodide emulsion 0.282 mole equivalent E4 seed emulsion B 1.18 mole equivalent F4 3.5N KBr aqueous solution The following silver potential control amount Seed emulsion B was thoroughly dispersed in solution A4 which was vigorously stirred at a liquid temperature of 75 ° C., and solution B4, solution C4 and solution D4 were added. The control double jet method was added in minutes.

The addition of D4 was completed when 2% of B4 was added.

Here, the addition rates of the B4, C4, and D4 solutions were changed in a function-like manner with respect to time so as to be commensurate with the critical growth rate, and small particles other than the growing seed crystal were generated and Ostwald ripening was performed. It was added at an appropriate addition rate so as not to cause polydispersion.

Solution D4, that is, fine grain silver iodide was supplied by B
A core / shell type silver halide emulsion having a multiple structure was prepared by changing the rate ratio (molar ratio) of the four liquids, that is, the aqueous ammoniacal silver nitrate solution to 2.2 with respect to the grain size (addition time).

By using the E4 solution, pAg during grain growth was kept at 6.2 throughout.

Immediately after the addition was completed, the pH was adjusted to 6.0 with acetic acid, and in order to remove excess salts, desalting was carried out in the same manner as in EM-1, gelatin was then added, and pAg = 8.
Redispersion was carried out under the conditions of pH = 5,5 to give Emulsion EM-3.
Observed with a scanning electron microscope, two parallel twin planes were observed.
It was a cubic particle having 0.95 μm on each side.

<Preparation of Emulsion EM-4> In the preparation method of EM-3, 171 minutes (80% of the total amount of silver added) after the addition of the C3 solution was started.
%)), And 1800 ml of a 4.37N potassium bromide aqueous solution was added at a constant flow rate over 8 minutes. During this time, the pAg was 6.2 to 10.
It rose to 0.

Except for the addition of this potassium bromide aqueous solution, E
EM-4 was obtained in exactly the same manner as M-3. About 200 samples were observed with a scanning electron microscope, and the average particle size was 0.9.
At 6 μm, the vertices of the cube were rounded. Also EM-3
Similarly, two twin planes parallel to each other were observed.

<Preparation of Emulsion EM-5> Monodisperse tabular emulsion EM-5 was prepared using the following four kinds of solutions.

[0119] A5 Gelatin _{29.4g HO (CH 2 CH 2 O} ) m- (CH (CH 3) CH 2 O) 17 - (CH 2 CH 2) nH (m + n ≒ 5.7) 10% aqueous ethanol solution 2.5ml seed emulsion B Equivalent to 0.17 mol Make up to 4800 ml with distilled water.

B5 Silver nitrate 1404.2 g Make up to 2360 ml with distilled water.

C5 Potassium bromide 982.8 g Make up to 2360 ml with distilled water.

D51.75N KBr aqueous solution
21.26 ml / min of the total amount of solution B5 and solution C5 in solution A5 using the mixing stirrer shown in JP-B-58-58288 and JP-A-58-58289 at the following silver potential control amount of 60 ° C. The additional growth was performed for 111 minutes at the flow rate of.

During this period, the silver potential was controlled to be +25 mV by using the solution D. After the addition of B5 and C5 was completed, 0.20 mol of the above silver iodide fine grain emulsion was added and stirred at 60 ° C. for 10 minutes.

After the completion, desalting was carried out using an aqueous solution of Demol N (manufactured by Kao Atlas) and an aqueous solution of magnesium sulfate in order to remove excess salts, and an aqueous gelatin solution containing 92.2 g of ossein gelatin was added and stirred and redispersed to 2500 ml. did.

When EM-9 was observed and measured by an electron microscope and the formation was analyzed, the average particle diameter (converted to a circle diameter) was 2.
08μm, average particle thickness 0.26μm, average aspect ratio 8.0,
The distribution was 26%.

<Preparation of Seed Emulsion C> A normal crystal seed emulsion C was prepared using the following solution.

A6 water 11.5l potassium bromide 2.05g ossein gelatin 100g B6 water 2.6l potassium bromide 65g potassium iodide 1.8g ossein gelatin 55g 0.2N sulfuric acid 38.5cc C6 water 3.0l potassium bromide 950g potassium iodide 27g Ocein gelatin 75 g D6 water 2.7 l Silver nitrate 95 g E6 water 3.2 l Silver nitrate 1410 g Solution A6 was placed in a reaction vessel and kept at 60 ° C., and other solutions were added at 23 ° C. At this time, solution B6 and solution D6 were added by the control double jet method over 30 minutes, and then,
Solution C6 and solution E6 were added by the control double jet method over 105 minutes. The stirring was performed at 500 rpm. The flow velocity was increased in proportion to the total surface area of the silver halide grains as the grains grew, and new growth nuclei did not occur during the inflow of the additive solution, and the so-called Ostwald ripening occurred to widen the grain size distribution. Added at no flow rate. When adding the silver ionic liquid and the halide ionic liquid, the pAg was adjusted to 8.3 ± 0.05 using potassium bromide liquid, and the pH was adjusted using sulfuric acid.
It was adjusted to 2.0 ± 0.1.

After the addition was completed, the pH was adjusted to 6.0, and then the same method and desalting treatment as described above were performed.

The resulting emulsion had a grain size of 0.30 μm, {111}
The tetradecahedral monodisperse grains were 5% in the plane and the other part was composed of {100} planes and the corners were slightly lacking and the silver iodide content was 2 mol%. This emulsion was designated as seed emulsion C.

<Preparation of Emulsion EM-6> First, the following solutions were prepared. All amounts are given per mol of silver halide.

A7 gelatin 10 g concentrated ammonia water 28 ml glacial acetic acid 3 ml 600 ml with water B7 potassium bromide 1.7 g potassium iodide 1.0 g gelatin 0.27 g water 37.0 ml C7 potassium bromide 90 g gelatin 2.0 g water 240 ml D7 (0.75N) AgNO ₃ 3.3g NH ₄ OH 2.3ml with water 37ml E7 AgNO ₃ 130g NH ₄ OH 100ml with water 240ml F7 potassium bromide 94g with water 165ml G7 AgNO ₃ 9.9g NH ₄ OH 7.0ml with water 110ml A7 solution to 40 ° C The mixture was kept warm and stirred with a stirrer at 800 rpm.
The pH of solution J was adjusted to 9.90 using acetic acid, and seed emulsion C was sampled in an amount of 0.03 mol per mol of silver halide and dispersed and suspended therein. Then, the G7 solution was added at a constant rate over 7 minutes to adjust the pAg to 7.3. Furthermore, B7 solution and D7 solution can be used simultaneously for 20 times.
Added over minutes. At this time, pAg was fixed at 7.30.
In addition, using potassium bromide solution and acetic acid over 10 minutes
After adjusting the pH to 8.83 and the pH to 9.0, the C7 solution and the E7 solution were simultaneously added over 30 minutes. At this time, the inflow rate ratio at the start of addition and the end of addition was 1:10, and the flow rate was increased with time. Moreover, the pH was decreased from 8.83 to 8.00 in proportion to the inflow.

Further, acetic acid was added to adjust the pH to 6.0. Then, an excessive salt is removed by a desalting method similar to the above to prepare an emulsion EM-
Got 6. The grains were hexahedral monodisperse silver iodobromide emulsions having an average grain size of 0.98 μm and a grain size variation coefficient of 16%.

(Chemical sensitization of emulsion) Emulsion EM-1 obtained
~ EM-6 was added while changing the amount of each ammonium thiocyanate salt at 55 ° C with stirring, per 1 mol of silver, and as a chemical sensitizer, 1 x 10 ^-6 mol of chloroauric acid and 8.7 x of sodium thiosulfate 10 ^-6 mol were added per mol of silver. After that, stir the mixture to make it 4-hydroxy-6-methyl-1,
Stabilization was performed by adding 3,3a, 7-tetrazaindene and 1-phenyl-5-mercaptotetrazole, and optimum chemical sensitization was performed for each.

Further, after adding the chemical sensitizer of EM-2 as EM-7, an emulsion was prepared by adding 1.2 × 10 ^-2 mol of the above silver iodide fine grain emulsion. Further, after adding the chemical sensitizer of EM-4 as EM-8, an emulsion was prepared in which the silver iodide fine grain emulsion described above was added in an amount corresponding to 1.2 × 10 ^-2 mol.

The outermost surface iodine content was determined by the XPS method, and the results are shown in Table 1.

(Quantification of thiocyanate compound) The amount of thiocyanate compound present in the emulsion and on the grain surface was determined according to the thiocyanate compound quantification methods 1 and 2.

An emulsion containing 1.5 × 10 ⁻² mol of silver halide was treated with 10 _CC of 1% KBr aqueous solution (when quantifying thiocyanate ion in the emulsion) or distilled water (when quantifying thiocyanate ion in the binder). The mixture was stirred at 40 ° C for 30 minutes. Then, centrifugation was performed at 1,000 rpm for 10 minutes using a centrifuge (20RP-5, manufactured by Hitachi Ltd.).

After diluting the above-prepared solution 100 times, ultrafiltration was performed using an air press 30 manufactured by Tosoh Corp., and then the filtrate was chromatographed using a CR system manufactured by Tosoh Corp. shown below. Graphic measurements were taken.

Column: TS IC-Anion SW Column temperature: 40 ° C. Detector: UV detector (210 nm) Eluent: Aqueous solution containing 7.5 mM Na ₂ HPO ₄ and 7.5 mM NaH ₂ HPO ₄ (pH 7.0) Flow rate: 0.7 mI / min Calibration curve: It was prepared by measuring an ammonium thiocyanate aqueous solution of 0.1 PPm to 10 PPm.

(Preparation of coating sample) The chemically sensitized emulsions EM-1 to EM-8 thus obtained were added with the additives described below to prepare an emulsion layer coating solution. At the same time, a protective layer coating solution described below was also prepared. The coating amount is 2.5 g / m ^{2 of} silver on one side,
Using two slide hopper type coaters so that the amount of gelatin attached would be 1.85 g / m ² , both sides were simultaneously coated on the support at a speed of 80 m / min and dried in 2 min 20 sec. .1 to No.48 were obtained. As a support, glycidyl methacrylate 50 wt%, methyl acrylate 10 wt
%, Butylmethacrylate 40 wt% Copolymer consisting of 3 types of monomers was diluted to 10 wt% and the resulting aqueous copolymer dispersion was used as a subbing solution for 175 μm X-ray film concentration 0.15 A blue-colored polyethylene terephthalate film base was used.

The additives used in 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 82 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 2-Mercaptobenzimidazole-5-sulfonate 1.5 mg

[0143]

[Chemical 7]

C ₄ H ₉ OCH ₂ CH (OH) CH ₂ N (CH ₂ COOH) ₂ 1 g 1-phenyl-5-mercaptotetrazole 15 mg diethylene glycol 7 g dextran (average molecular weight 60,000) 600 mg sodium polyacrylate (average molecular weight 3.6 2.5 g Next, the following was prepared as a protective layer coating liquid. The additive is shown in the amount per liter of coating liquid.

Lime-treated inert gelatin 68 g Acid-treated gelatin 2 g Sodium-i-amyl-n-decylsulfosuccinate 0.3 g Polymethylmethacrylate (matting agent having an area average particle size of 3.5 μm) 1.1 g Silicon dioxide particles (area average particle size) 1.2 μm matting agent) 0.5 g Ludox AM (DuPont) (colloidal silica) 30 g (CH ₂ = CHSO ₂ CH ₂ ) ₂ O (hardening agent) 7 mg Glyoxal 40% aqueous solution (hardening agent) 2.0 ml

[0146]

[Chemical 8]

Sensitometry (Evaluation of Photographic Performance) In sensitometry, a sample was sandwiched between two intensifying screens NR-160 (manufactured by Konica Corporation), and a tube voltage of 80 kv was applied through an aluminum wedge.
p, tube current 100 mA, X-ray irradiation for 0.05 seconds. Next, using a roller-conveying type automatic developing machine SRX-503, development and fixing were carried out with SR-DF (both manufactured by Konica Corporation) of a developing solution and a fixing solution.

The processing time was dry to dry for 45 seconds, and the sensitivity was obtained. The temperature during processing is 35 ℃ for development and 33 for fixing.
C., washed with water at 20.degree. C., and dried at 50.degree. Sensitivity is fog +
It is expressed as the reciprocal of the exposure dose that gives a density of 1.0.
The relative sensitivity is shown with the sensitivity of 100 ° C., 55% RH, and one day storage as 100.

(Evaluation of Scratch Resistance) 25 samples were prepared.
After conditioning the humidity for 1 hour under the condition of ℃ and 30% RH, load 100g on a 2 cm ² area using a commercially available nylon scrubbing brush under the same conditions.
And rubbed at a speed of 2 cm per second. After performing the above-mentioned automatic development treatment in an unexposed state, the number of blackened scratches was counted.

(Evaluation of Silver Tone) The prepared sample was exposed to light so that the transmission density after development was 1.2, and then developed using the above-mentioned automatic processor. The developed sample thus obtained was allowed to stand for 7 days at a temperature and humidity of 50 ° C. and 80% RH, and then observed with a Schaukasten to visually evaluate the silver color tone by transmitted light according to the following criteria.

1. Yellowish black 2. Black with a slight yellow tint 3. Reddish black color 4. 4. Reddish black color 5. Pure Black The above results are shown in Table 1 below.

[0152]

[Table 1]

As is apparent from the table, the sample of the present invention has less scratch blackening, and the image has a pure black tone and high sensitivity.

[0154]

According to the present invention, a silver halide photographic light-sensitive material having developed silver color tone of pure black color, scratch resistance to fog resistance, high sensitivity and suitability for rapid processing was obtained.

Claims (4)

[Claims] 1. A silver halide grain having an aspect ratio of less than 2, two or more twin planes parallel to each other, and the amount of a thiocyanic acid compound present on the surface of the silver halide grain is 1.0 × per 1 mol of silver. A silver halide photographic emulsion characterized in that it is in the range of 10 ⁻³ mol to 4.0 × 10 ⁻² mol. 2. A silver halide photographic light-sensitive material having at least one silver halide emulsion layer on a support,
A silver halide photographic light-sensitive material, wherein the silver halide grains contained in the silver halide emulsion layer are the silver halide grains according to claim 1. 3. The average silver iodide content of silver halide grains is
2. The silver halide photographic emulsion according to claim 1, wherein the average silver iodide content in the vicinity of the outermost surface of the silver halide grains is 1.0 mol% or more and is 1.0 mol% or more. 4. A silver halide photographic light-sensitive material having at least one silver halide emulsion layer on a support,
A silver halide photographic light-sensitive material, wherein the silver halide grains contained in the silver halide emulsion layer are the silver halide grains according to claim 3.