JPH05265119A - Silver halide photographic sensitive material - Google Patents

Abstract

PURPOSE:To obtain the silver halide photographic sensitive material having high sensitivity and high-speed processability and superior storage stability by using a specified silver halide emulsion. CONSTITUTION:This silver halide emulsion contains silver halide grains composed of silver iodobromide and a thiocyanate compound in an amount of 2X10<-3>-6Xl0<-3> per 1mol of silver halide present on the surface of each grain and in an amount of <=2.0X10<-2>mol per 1mol of silver halide in the binder of the emulsion. As the thiocyanate to be used here, water-soluble thiocyanates not adversely affecting photographic performances, preferably, such as ammonium and metal salts like K and Na salts. Hardly soluble salts, such as silver salts, may be added as fine particles, and the thiocyanate may be added at any time during forming the silver halide grains but preferably, before a desalting process.

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 light-sensitive material, and particularly to provide a silver halide emulsion having high sensitivity, rapid development, and good storage stability.

[0002]

It is needless to say that one of the performances always required in developing a silver halide photographic light-sensitive material is to obtain a silver halide emulsion having higher sensitivity. For example, by increasing the sensitivity of the X-ray sensitive material, it is possible to reduce the radiation exposure dose of the subject. On the other hand, the demand for rapid processing has been increasing in recent years, and development of emulsions with rapid development has been awaited. Various methods have been reported for the technique of increasing the sensitivity. US Patent No. 2,2
22,264, 3,320,069, JP-A-6
No. 2-18538 describes a method for obtaining highly sensitive particles by allowing a thiocyanate salt to be present during grain formation. However, in these patents, the amount of thiocyanic acid added in the examples was several mol% with respect to silver, and the presence of such a large amount of thiocyanic acid compound in the emulsion markedly deteriorated the storage stability. Also,
U.S. Pat. No. 4,332,887 discloses a technique for obtaining a preferable grain shape by using a thiocyanate salt as a silver halide solvent, but it is essential to remove it after grain formation. For this reason, sufficient sensitivity could not be obtained.

JP-A-59-162540 discloses a technique for increasing the sensitivity by epitaxially growing silver thiocyanate on a specific portion (for example, an edge) on a silver halide host grain. In the present invention, the epitaxial formation of silver thiocyanate cannot be confirmed at least by observation with an electron microscope.
Different from No. 40. The amount of silver thiocyanate deposited as disclosed in the examples of the patent was 5 mol% based on 1 mol of silver of the host particles. When a large amount of silver thiocyanate is deposited on the silver halide grains in this way,
There has been a problem that the photographic material has a marked increase in fog over time.

In Japanese Patent Laid-Open No. 64-37545, silver 1 is used.
An example of a monomethine dye spectrally sensitized emulsion containing 4 × 10 ⁻³ moles of thiocyanate per mole is disclosed, but since these grains contain 20 mole% or more of silver chloride, the usual It was disadvantageous for spectral sensitization with dyes. Japanese Unexamined Patent Publication No. 1-100533 discloses a technique of suppressing fogging caused by color sensitization by using thiocyanate. However, thiocyanic acid compound is added in an amount of 13 mmol per mol of silver before and after washing with water. There is. If such a large amount is added after the water washing step, fogging will occur over time, which is not suitable for practical use. Further, in the case of being added before the water washing step, the pAg at the time of addition is 11, which means that most of thiocyanate is removed during the water washing, so that sufficient sensitivity cannot be obtained.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a silver halide photographic light-sensitive material having high sensitivity, rapid development progress and excellent storage stability.

[0006]

The objects of the present invention have been achieved by the following (1) to (3). (1) The silver halide grains contained in the silver halide emulsion are silver iodobromide, and the amount of the thiocyanic acid compound present on the surface of the silver halide grains is 2 × 10 ⁻³ per mol of silver.
And the mol 6 × 10 ^-3 or less, and wherein the amount of thiocyanate compound contained in the binder of the silver halide emulsion is not more than 1 mol of silver per 2.0 × 10 ^-2 mol Photographic silver halide emulsion. (2) In a silver halide photographic light-sensitive material having at least one silver halide emulsion layer on a support, the surface of the silver halide grains is silver iodobromide, and a thiocyanate compound present in the silver halide grains. The amount of
It is 2 × 10 ⁻³ mol or more and 2 × 10 ⁻² mol or less, and the amount of the thiocyanic acid compound contained in the binder of the silver halide emulsion layer is 3.0 × 10 ⁻³ mol or less per 1 mol of silver. A silver halide photographic light-sensitive material characterized in that (3) The content of the thiocyanic acid compound in the silver halide emulsion layer is 20% or less based on the added amount, and the silver halide photographic light-sensitive material or the photographic halogenation described in 1 or 2 above. Method for producing silver emulsion.

The specific structure of the present invention will be described in detail below. As the thiocyanate used in the present invention, a metal salt or a water-soluble salt such as NH4SCN can be used, but in the case of a metal salt, care should be taken to use a metal element that does not adversely affect photographic performance. KSCN, NaSCN and the like are preferable. Further, a sparingly soluble salt such as AgSCN may be added as fine particles. in this case,
The size of the fine particles is preferably 0.2 μm or less, and particularly preferably 0.05 μm or less. The thiocyanate may be added at any time during grain formation, but it is preferably before the desalting process. The thiocyanic acid added during grain formation is incorporated into the silver halide grains depending on the amount added and the pBr added. The addition amount is 2 × 10 ⁻³ mol or more, preferably 5 × 10 ⁻³ mol or more, and particularly preferably 1 × 10 ⁻² mol or more, relative to the final silver addition amount of 1 mol. PB when adding
r is particularly important. If it is too low, the incorporation rate of the thiocyanic acid compound into the silver halide grains (ratio of the amount incorporated on the grain surface with respect to the addition amount) is significantly reduced, and it becomes difficult to bring out sufficient performance. On the other hand, it was confirmed by experiments that if it is too high, the uptake rate increases, and fogging occurs accordingly. The uptake rate is preferably 20% or less. Therefore, the pBr from the addition of the thiocyanate compound to the start of the desalting process is preferably 1.50 or more and 4.0 or less, and particularly preferably 2.0.
It is above 3.50. Especially pB just before the start of the desalting process
r is preferably 1.5 or more and 3.5 or less, and particularly preferably 2.0 or more and 3.2 or less. The thiocyanic acid compound that has not been incorporated is preferably removed in the desalting process. Usually, the desalting step is carried out by washing with water using a sedimentation method, as shown in the examples. This water washing process is repeated several times until the desired salt concentration is obtained, but the pBr immediately before the start of water washing must maintain the pBr preferable for the addition of the thiocyanate compound.

PB from the end of the desalting process to the start of chemical sensitization
r is from the surface of the thiocyanate compound particles to the binder
In order to prevent the release into the
And particularly preferably 3.0 or more. Line like above
The degree of desalination and milk
Depending on the pBr of the agent, the thiocyanate compound is the binder
It also exists inside. This thiocyanate compound can be used naturally over time.
The abundance of silver is 1 because it aggravates fogging in the air.
3 x 10 per mole^-3Must be below molar. Good
2x10 is better^-3It is not more than 1 mol, particularly preferably 1
× 10^-3It should be below molar or not present at all. Well
On the other hand, the amount of thiocyanate compound present in the particles is high.
If it is too small, it causes fogging, and if it is too small, sensitization and
The effect of promoting development cannot be obtained. Therefore, the contract of this patent
It is necessary that the amount of the thiocyanic acid compound be within the range of the requirement.
The amount of thiocyanate compound present on the surface of silver halide is
Preferably 2 x 10 per mole of silver ^-3Mol ~ 1 x 10^-2
Mol, preferably 2 × 10^-3Mol ~ 6 x 10^-3Mo
The thiocyanic acid compound, which is a polymer, is added when chemical sensitization after washing with water.
Can be added. Calculate the uptake rate at this time
The addition amount at this time is the thiocyanate added before and after washing with water.
It is the sum of the compounds.

(Determination of thiocyanate compound in light-sensitive material and emulsion) In order to obtain high sensitivity and rapid development progress under good natural aging, which is an object of the present invention, finally, It is necessary to control the amount of thiocyanate compound in the obtained emulsion or light-sensitive material as claimed in the present application. It can be confirmed by the following method whether or not the intended state has been realized (see Examples for details of the actually used model and measurement conditions). 1. Determination of thiocyanate ion in emulsion before coating 1% KB in emulsion containing 1.5 × 10 ^-2 mol of silver halide
Add 10 cc of aqueous solution and stir at 40 ° C for 30 minutes. The emulsion is centrifuged to completely separate the emulsion, and the supernatant is diluted 100 times. After ultrafiltration of the diluted solution, the thiocyanate ion in the diluted solution is quantified by ion chromatography. For the quantification, a calibration curve prepared in advance using a thiocyanic acid compound aqueous solution is used.

2. Determination of thiocyanate ion on the surface of silver halide grains in the emulsion before coating: 10 ml of distilled water was added to an emulsion containing 1.5 × 10 ^-2 mol of silver halide, and the mixture was stirred at 40 ° C. for 30 minutes. The emulsion is centrifuged to completely separate the emulsion, and the supernatant is diluted 100 times. After ultrafiltration of the diluted solution, the thiocyanate ion in the diluted solution is quantified by ion chromatography. For the quantification, a calibration curve prepared in advance using a thiocyanic acid compound aqueous solution is used. By subtracting the value thus obtained from the value of all thiocyanate ions in the emulsion previously obtained, the amount of thiocyanate ions attached to the target grain surface is obtained.

3. Quantification of thiocyanate ion in light-sensitive material in product form The target emulsion layer containing 0.1 g of silver was peeled from the light-sensitive material and immersed in 49 cc of distilled water. After adding 1 cc of 5% KBr aqueous solution to this solution, ultrasonic agitation is performed at 40 ° C. for 30 minutes. After centrifuging this solution, the supernatant is filtered. The filtrate is diluted 10-fold and then the thiocyanate ion contained therein is quantified by ion chromatography. For the quantification, a calibration curve prepared in advance using a thiocyanic acid compound aqueous solution is used.

4. Quantification of thiocyanate ions on the surface of silver halide grains in a light-sensitive material in the form of a product The target emulsion layer containing 0.1 g of silver was peeled from the light-sensitive material and immersed in 50 cc of distilled water. This solution at 40 ℃ 3
Stir for 0 minutes. After further centrifuging, the supernatant is filtered. The filtrate is diluted 10-fold and then the thiocyanate ion contained therein is quantified by ion chromatography. For the quantification, a calibration curve prepared in advance using a thiocyanic acid compound aqueous solution is used. By subtracting the value thus obtained from the value of all thiocyanate ions in the emulsion previously obtained, the amount of thiocyanate ions attached to the target grain surface is obtained. By performing this operation after peeling layers by layer, even in a multi-layer coated product light-sensitive material, accurate information on the emulsion of the target layer can be obtained.

Next, the emulsion grains used in the present invention will be described. The diameter of a sphere having the same volume as the emulsion grains (hereinafter referred to as sphere-equivalent average grain size) is preferably 0.4 μm or more and less than 2.0 μm, and particularly preferably 0.5 or more and less than 1.5 μm. The particle size distribution should be narrow. The silver halide grains in the emulsion are cubic, octahedral, 1
It may have a regular crystal form such as a tetrahedron,
It may also have an irregular crystal form such as a sphere, a plate, or a potato. It may consist of a mixture of particles of various crystal forms. When a monodisperse emulsion is used as an emulsion in the practice of the present invention, the rate of addition of the aqueous solution of silver nitrate and the water-soluble halide can be increased with the growth of silver halide grains in the preparation of the monodisperse emulsion. By increasing the addition rate, the particle size distribution can be made more monodisperse, and the addition time can be shortened, which is advantageous for industrial production. Further, it is also preferable in that the chance of structural defects being formed inside the silver halide grain is reduced.

As a method for accelerating the addition rate, as described in JP-B-48-36890, JP-A-52-16364, and JP-A-55-142329, the addition rate of an aqueous silver salt solution and an aqueous halide solution is described. May be increased continuously or stepwise. The upper limit of the addition rate may be a rate just before the generation of new grains, and the values are temperature, pH, pAg, degree of stirring, composition of silver halide grains, solubility, grain size, inter-grain distance, or protection. It changes depending on the type and concentration of colloid. A method for producing a monodisperse emulsion is known, and for example, J. Phot. Sci. 12, 242 to 251.
(1963), JP-B-48-36890, 52-1.
6364 and JP-A-55-142329, and the technology described in JP-A-57-179835 can be employed. The silver halide grains used in the present invention may be core-shell type monodisperse emulsions, and these core-shell emulsions are disclosed in JP-A-54-4.
It is known from No. 8521 and the like. When a monodisperse emulsion is used as an emulsion in the practice of the present invention, a known method can be used for producing the polydisperse emulsion. For example THJ
ames, "The Theory of the Photographic Process" 4th edition, published by Macmillan (1977), pages 38-104, etc., neutral method, acidic method, ammonia method,
Forward mixing, back mixing, double jet method, controlled
It can be manufactured by applying methods such as a double jet method, a conversion method, and a core / shell method.

Further, tabular grains whose grains are 5 times or more the grain thickness are preferably used in the present invention (for details, RE
SEARCH DISCLOSURE Volume 225 Item 22534, p.20
~ 58, January issue, 1983, and JP-A-58-127.
921 and 58-113926). The tabular silver halide grains can be produced by appropriately combining methods known in the art. The tabular silver halide emulsion is described in JP-A-58-127,921.
JP-A-58-113,927, JP-A-58-11
It can be easily prepared by referring to the method described in US Pat. No. 3,928 and US Pat. No. 4,439,520. The projected area diameter of the tabular emulsion of the present invention is preferably 0.3 to 2.0 μm, and particularly preferably 0.5 to 1.2 μm. Further, the distance between the flat surfaces (particle thickness) is 0.05 μm to 0.3.
The aspect ratio is preferably 3 or more and less than 20, and particularly preferably 4 or more and less than 8 as the aspect ratio. In the tabular silver halide emulsion of the present invention, silver halide grains having an aspect ratio of 2 or more are present in an amount of 50% (projected area) or more, particularly 70% or more of all grains, and the average aspect ratio of the tabular grains is 3 or more, especially 4
It is preferably -8. Among the tabular silver halide grains, monodisperse hexagonal tabular grains are particularly useful grains. The details of the structure and manufacturing method of the monodisperse hexagonal tabular grain according to the present invention are described in JP-A-63-151618.

Silver iodobromide is used as the halogen composition of the silver halide emulsion of the present invention. The effect of improving the progressiveness was remarkable in the silver iodobromide system. The silver iodide content is preferably less than 10 mol% and 1 mol% or more, and particularly preferably less than 5 mol% and 1 mol% or more for rapid development. The silver halide grains may be composed of a uniform layer, but it is preferable that the inside and the surface layer have different halogen compositions, and it is particularly preferable that at least the outermost surface of the silver halide grains is a silver iodide-containing layer. Silver chloride and silver chlorobromide are not preferable because the adsorption of the sensitizing dye is insufficient.

The silver iodide content of each emulsion grain is, for example, X.
It can be measured by analyzing the composition of each silver halide grain using a line microanalyzer. The term "coefficient of variation of the silver iodide content of individual grains" used herein means, for example, the silver iodide content when the silver iodide content of at least 100 emulsion grains is measured by an X-ray microanalyzer. 1 divided by the standard silver iodide content
It is a value obtained by multiplying by 00. The 53rd Photographic Society of Japan
Volume 2 (J.Soc.Photogr.Sci.Technol.Japan Vol.5
3, No. 2, 1990), pages 125-128, the results of measuring the silver iodide content for each internal structure of each silver halide grain by an analytical electron microscope are reported. JOURNAL OF IMAGI
NG SCIENCE Vol.31, No.1, 1987 15-26
The page shows the intra-grain microstructure related to the halogen composition of tabular grains (Low-temperature luminescence m
The method of observing using iroscopy) has been reported in detail. Also, JOURNAL OF IMAGING SCIENCE Vol. 32,
No. 4, pp. 160-177, pp. 160-177, when silver chloride is deposited on silver iodobromide having an intragrain silver iodide distribution, silver iodide determines the silver chloride deposition site (site direct).
It has been reported in detail. Furthermore, the Journal of the Photographic Society of Japan 3
Vol. 5, 1972, pages 213 and subsequent pages, it is reported that nonuniformity of halogen composition in grains can be observed by directly observing grains at low temperature using a transmission electron microscope. By using the method as described above, the fine structure of the silver halide composition can be observed for each silver halide grain.

Next, a method for forming a silver iodobromide layer on the grain surface will be described. In forming the final grain surface, it is necessary to supply iodine so as to eliminate the inter-grain distribution of the surface iodine content of individual grains. The method for forming the silver iodobromide layer on the grain surface is described in, for example, British Patent No. 63.
There are so-called halogen conversion methods as described in US Pat. No. 5,841, and US Pat. No. 3,622,318. As a method for forming a silver iodobromide layer on the grain surface, a method of simultaneously adding a silver nitrate solution and an iodine ion-containing solution, AgI and / or
Alternatively, a method of adding fine silver halide grains having an AgBrI composition, a method of dissolving potassium iodide or potassium iodide and potassium bromide in a gelatin solution, and then cooling and setting the solid state can be applied. Among them, a method of simultaneously adding a silver nitrate solution and a solution containing iodine ions,
The method of adding fine silver halide grains having AgI and / or AgBrI composition is a more preferable method for the present invention. Further, an organic compound containing iodine as described in JP-A-63-220187 may be added to the bulk liquid in the reaction vessel. Representative compounds include, but are not limited to, the following compounds.・ ICH ₂ CH ₂ COOH ・ ICH ₂ COOH ・ ICH ₂ CN

In the light-sensitive material of the present invention, at least one photosensitive silver halide emulsion layer may be provided on one side of the support, or at least one layer may be provided on both sides of the support. Good. The light-sensitive material of the present invention may have a hydrophilic colloid layer in addition to the light-sensitive silver halide emulsion layer, if desired. For example, a surface protective layer is preferably provided. In the light-sensitive material of the present invention, the amount of gelatin on the side having the hydrophilic colloid layer including the light-sensitive silver halide emulsion layer is preferably in the range of 1.70 to 2.50 g / m ² . If the photosensitive emulsion layer is present only on one side of the support, the amount of gelatin on that side is preferably within the above range, and if the photosensitive emulsion layer is on both sides of the support, the amount of gelatin on both sides is Is preferably within the above range. When there is no hydrophilic colloid layer other than the photosensitive emulsion layer, the amount of gelatin in the photosensitive emulsion layer is within the above range. Gelatin content is more preferably in the range of 1.80~2.40g / m ^2, in particular in the range of 1.90~2.30g / m ² is desirable.

The melting time of the light-sensitive material of the present invention is preferably set to 8 minutes or longer and 45 minutes or shorter. The melting time referred to in the present invention means that at least one layer of silver halide constituting the photosensitive material when the photosensitive material cut into 1 cm × 2 cm is immersed in a 1.5 wt% sodium hydroxide aqueous solution at 50 ° C. It is the time until the emulsion layer begins to melt.

In order to effectively utilize the effects of the present invention,
During chemical sensitization during the emulsion preparation process as described in JP-A-2-68539, it is preferable to allow a silver halide-adsorptive substance to be present. This silver halide-adsorptive substance may be added at any time during grain formation, immediately after grain formation, before or after the start of post-ripening, but a chemical sensitizer (for example, gold or sulfur sensitizer) is added. It is preferable to be added before the chemical sensitizer or at the same time as the chemical sensitizer. The silver halide adsorptive substance may be added at any temperature of 30 ° C. to 80 ° C., but at 50 ° C. for the purpose of enhancing the adsorptivity.
The range of -80 ° C is preferred. The pH and pAg may be arbitrary, but at the time of chemical sensitization, the pH is 5 to 10, pAg
It is preferably from 7 to 9.

In the present invention, the silver halide adsorbing material means a sensitizing dye or a class of photographic performance stabilizers. That is, azoles {eg, benzothiazolium salt, benzimidazolium salt, imidazoles, benzimidazoles, nitroindazoles, triazoles, benzotriazoles, tetrazoles, triazines, etc.); mercapto compounds (eg mercaptothiazoles, Mercaptobenzothiazoles, mercaptoimidazoles, mercaptobenzimidazoles, mercaptobenzoxazoles, mercaptothiadiazoles, mercaptooxadiazoles, mercaptotetrazoles, mercaptotriazoles, mercaptopyrimidines, mercaptotriazines and the like}; for example, oxadrine Thioketo compounds such as thione; azaindenes {eg triazaindenes, tetraazaindenes (especially 4-hydroxy) Substituted (1,3,3a, 7) tetraazaindenes), pentaazaindenes such like);
Many compounds known as antifoggants or stabilizers such as can be mentioned as the silver halide adsorbing material. Furthermore, purines or nucleic acids, or polymer compounds described in JP-B-61-36213 and JP-A-59-90844 are also adsorbable substances that can be used. Among them, azaindenes, purines, and nucleic acids can be preferably used in the present invention. The amount of these compounds added is 10 to 300 m per mol of silver halide.
g, preferably 20-200 mg.

As the silver halide adsorbing material of the present invention,
Sensitizing dyes can achieve favorable effects. As the sensitizing dye, cyanine dye, merocyanine dye, complex cyanine dye, complex merocyanine dye, holoholer cyanine dye, styryl dye, hemicyanine dye, oxonol dye, hemioxonol dye and the like can be used. Useful sensitizing dyes used in the present invention are, for example, U.S. Pat. Nos. 3,522,052 and 3,619,
No. 197, No. 3,713,828, No. 3,615,6
No. 43, No. 3,615, 632, No. 3,617, 29
No. 3, No. 3,628,964, No. 3,703,377
Issue No. 3,666,480 Issue 3,667,960
Nos. 3,679,428 and 3,672,897
Issue No. 3,769,026 Issue No. 3,556,800
Issue No. 3,615,613 Issue No. 3,615,638
Nos. 3,615,635 and 3,705,809
No. 3,632,349, No. 3,677,765
No. 3,370,449, No. 3,770,440
No. 3, ibid. 3,769,025, ibid. 3,745,014
Issue 3, Issue 3,713,828, Issue 3,567,458
Nos. 3,625,698, 2,526,632
No. 2,503,776, JP-A-48-76525.
And Belgian Patent No. 691,807. The amount of sensitizing dye added is 2 per mol of silver halide.
00 mg or more and less than 1000 mg, preferably 300 mg or more 5
Less than 00 mg is good. Specific examples of the sensitizing dye effective in the present invention are shown below.

[0024]

[Chemical 1]

[0025]

[Chemical 2]

The combined use of the sensitizing dye and the above-mentioned stabilizer is a preferred embodiment. The sensitizing dye used in the present invention may be added after chemical sensitization and before coating. The chemical sensitization method of the silver halide emulsion used in the present invention may be a sulfur sensitization method, a selenium sensitization method, a reduction sensitization method, a gold sensitization method, etc. in the presence of the above-described silver halide adsorbing substance. Known methods can be used, either alone or in combination.
The selenium sensitization method is a particularly important means for the present invention.

As the selenium sensitizer used in the present invention, the selenium compounds disclosed in conventionally known patents can be used. That is, usually, an unstable selenium compound and / or a non-unstable selenium compound is added,
It is used by stirring the emulsion at a high temperature, preferably 40 ° C. or higher, for a certain period of time. Unstable selenium compounds are disclosed in JP-B-44-15748 and JP-B-43-13489.
No. 2, JP-A-2-130976, Japanese Patent Application No. 2-22930.
It is preferable to use the compounds described in No. 0 and the like. Specific unstable selenium sensitizers include isoselenocyanates (eg, aliphatic isoselenocyanates such as allyl isoselenocyanate), selenoureas, selenoketones, selenamides, selenocarboxylic acids (eg,
2-selenopoupionic acid, 2-selenobutyric acid), selenoesters, diacyl selenides (for example, bis (3-chloro-2,6-dimethoxybenzoyl) selenide), selenophosphates, phosphine selenides, colloidal metals Examples include selenium. The preferred types of labile selenium compounds are described above, but are not limiting. Speaking to a person skilled in the art as an unstable selenium compound as a sensitizer for a photographic emulsion, the structure of the compound is not so important as long as selenium is unstable,
It is generally understood that the organic portion of the selenium sensitizer molecule carries selenium and plays no role other than allowing it to be present in the emulsion in an unstable form. In the present invention, the labile selenium compound having such a broad concept is advantageously used. Examples of the non-labile selenium compound used in the present invention include JP-B-46-4553 and JP-B-53-344.
The compounds described in JP-B No. 92 and JP-B-52-34491 are used. Examples of non-labile selenium compounds include selenious acid, potassium selenocyanide, selenazoles, quaternary salts of selenazoles, diaryl selenides, diaryl diselenides, dialkyl selenides, dialkyl diselenides, 2-selenazolidinediones, Examples include 2-selenooxazolidinethione and derivatives thereof. As selenium sensitizers which are particularly preferably used in the present invention, compound examples 1 to 3 described in Japanese Patent Application No. 183863/93.
It is 8, but the following compounds are particularly preferable.

[0028]

[Chemical 3]

The addition amount of the selenium sensitizer used in the present invention varies depending on the activity of the selenium sensitizer used, the type and size of silver halide, the temperature and time of ripening, etc.
It is preferably 1 × 10 ⁻⁵ mol or more per mol of silver halide. More preferably 1 × 10 ⁻⁷ mol or more and 1 × 10
^-5 mol or less. The temperature of chemical ripening when the selenium sensitizer is used is preferably 45 ° C. or higher. More preferably, it is 50 ° C. or higher and 80 ° C. or lower. pAg and pH are arbitrary. For example, the effect of the present invention can be obtained in a wide pH range of 4 to 9. Among the noble metal sensitizing methods, the gold sensitizing method is a typical one, which uses a gold compound, mainly a gold complex salt.
Noble metals other than gold, for example, platinum, palladium, iridium and other complex salts may be contained. Specific examples thereof are described in US Pat. No. 2,448,060 and British Patent 618,061. As the sulfur sensitizer, various sulfur compounds such as thiosulfates, thioureas, thiazoles, and rhodanines can be used in addition to the sulfur compounds contained in gelatin. Specific examples are US Patent 1,
574,944, 2,278,947, 2,4
No. 10,689, No. 2,728,668, No. 3,50
Nos. 1,313 and 3,656,955. The combined use of sulfur sensitization with thiosulfate and gold sensitization can effectively exert the effect of the present invention. As the reduction sensitizer, a primary tin salt, an amine, formamidinesulfinic acid, a silane compound or the like can be used. Prefab-2 X-Ray Ortho

There are no particular restrictions on the various additives and the like used in the photographic light-sensitive material of the present invention. For example, those described in the following relevant parts can be used. Item This section 1) Silver halide emulsion and JP-A-2-68539, page 8, lower right column, lower column, 6 from its production line to the same, page 10, upper right column, 12th column, 3-245 37 Gazette, page 2, lower right column, line 10 to page 6, upper right column, line 1; page 10, upper left column, line 16 to page 11, lower left column, line 19; Japanese Patent Application No. 2-225637. 2) Chemical sensitization method Japanese Patent Application No. 2-68539, page 10, upper right column, line 13 to same upper left column, line 16, Japanese Patent Application No. 3-105035. 3) Antifoggant, Japanese Patent Application No. 2-68539, page 10, lower left column, line 17 Stabilizers to page 11, upper left column, line 7 and page 3, lower left column, line 2 to page 4, lower left Column. 4) Color improver JP-A-62-276539, page 2, lower left column, line 7 to page 10, lower left column, line 20; JP-A-3-94 249, page 6, lower left column, line 15 to Page 11, right upper column, line 19 5) Spectral sensitizing dye JP-A-2-68539, page 4, lower right column, line 4 to page 8, lower right column. 6) Surfactant JP-A-2-68539, page 11, upper left column, line 14 Antistatic agent to page 12, upper left column, line 9 7) Matting agent, slipping agent JP-A-2-68539, page 12, upper left column, line 10 Plasticizer to the same upper right column, line 10; page 14, lower left column, line 10 to right lower column, line 1

8) Hydrophilic Colloid JP-A-2-68539, page 12, upper right column, line 11 to lower left column, line 16 9) Hardener JP-A-2-68539, page 12, lower left column, line 17 to page 13, upper right column, line 6 10) Supports JP-A-2-68539, page 13, upper right column, lines 7 to 20. 11) Crossover JP-A-2-264944, page 4, upper right column, line 20, from cut method, page 14 upper right column. 12) Dyes and mordants JP-A-2-68539, page 13, lower left column, line 1 to page 14, lower left column, line 9 No. 3-24537, page 14, lower left column to page 16, lower right column. 13) Polyhydroxy JP-A-3-39948, page 11, upper left column to benzenes, page 12, lower left column, EP Patent No. 452772A. 14) Layer structure JP-A-3-198041. 15) Development processing method JP-A-2-103037, page 16, upper right column, line 7 to page 19, left lower column, line 15 and JP-A-2-115837, page 3, lower right column, line 5 Page 6, upper right column, line 10 Hereinafter, the present invention will be described in more detail with reference to examples.

[0032]

EXAMPLES Tabular grains having a silver iodide content of 2.0 mol% (grains 1 to
Preparation of 3)) 4.5 g of potassium bromide in 1 liter of water,
Gelatin 20.6g, thioether HO (CH ₂ ) ₂ S (CH ₂ ) ₂ S (C
_2.5 cc of 5% aqueous solution of H ₂ ) ₂ OH was added, and 37 cc of silver nitrate aqueous solution (silver nitrate 3.4
3 g) and potassium bromide 2.97 g and potassium iodide 0.3
33cc of an aqueous solution containing 63g was added by the double jet method to 3
Added in 7 seconds. Next, the temperature was raised to 70 ° C. and 53 cc of an aqueous silver nitrate solution (4.90 g of silver nitrate) was added over 13 minutes. Here, 15 cc of 25% aqueous ammonia solution was added, and after physically aging for 20 minutes at the same temperature, 14 cc of 100% acetic acid solution was added. Subsequently, an aqueous solution of 133.3 g of silver nitrate and an aqueous solution of potassium bromide containing 1.8 mol% potassium iodide were added over 35 minutes by the control double jet method while maintaining pBr 2.0. Next, after adjusting the pBr to 2.8 using an aqueous solution of silver nitrate, 2N
The potassium thiocyanate solution was added in the amount shown in Table 1. After physical aging for 10 minutes at the same temperature, 35 ℃
Lowered the temperature to. Subsequently, an aqueous solution containing 1.5 g of compound B was added to bring the total amount to 3 liters, and then the pH was lowered using sulfuric acid until the silver halide precipitated. Then 85% of the total volume
The supernatant liquid was removed (first washing with water). Further, the same amount of distilled water as that removed was added, and then sulfuric acid was added until the silver halide was precipitated. The supernatant liquid of 85% of the total volume was removed again (second water washing). The same operation as the second washing with water was repeated once (third washing with water) to complete the desalting process.

[0033]

[Chemical 4]

The temperature was raised again to 56 ° C., 30 g of gelatin, 2.35 g of phenoxyethanol and 0.8 g of sodium polystyrene sulfonate as a thickening agent were added, and the pH was adjusted to 5.90 and pBr to 3.8 with caustic soda and silver nitrate solution. .. Thus, the total silver iodide content is 2.0 mol%,
Average projected area diameter 1.13 to 1.16 μm, thickness 0.1
60 to 165 μm, variation coefficient of diameter 18.0 to 19.0
% Monodisperse tabular grains 1 to 3 were obtained.

(Preparation of Particles 4 and 5) Particles 1 to 1 except that the pBr when adding potassium thiocyanate was 3.5.
Prepared as in 3. Thus, monodisperse tabular grains 4 having a total silver iodide content of 2.0 mol%, an average projected area diameter of 1.12 μm, a thickness of 0.175 μm, and a diameter variation coefficient of 17.2% and an average projected area diameter of 1.14 μm, a thickness of 0.
Monodisperse tabular grains 5 having a diameter of 171 μm and a variation coefficient of diameter of 18.2% were obtained.

(Chemical Sensitization) Next, the grains 1 to 5 were chemically sensitized while being kept at 56 ° C. with stirring. First, 0.043 mg of thiourea dioxide was added, and the mixture was held as it was for 22 minutes for reduction sensitization. Next, 20 mg of 4-hydroxy-6-methyl-1,3,3a, 7-tetraazaindene and 400 mg of sensitizing dye A were added. Furthermore, 0.83 g of calcium chloride aqueous solution was added. Subsequently, 1.3 g of sodium thiosulfate, 2.7 mg of selenium compound-1, 2.6 mg of chloroauric acid and 90 mg of potassium thiocyanate were added, and 40 minutes later, the mixture was cooled to 35 ° C. Thus, the preparation of emulsions 1 and 5 was completed.

[0037]

[Chemical 5]

(Preparation of Emulsion Coating Layer) The following chemicals were added to chemically sensitized emulsions 1 to 3 per mol of silver halide to prepare a coating solution (Type A).・ 2,6-bis (hydroxyamino) -4-diethylamino-1,3,5-triazine 72 mg ・ trimethylol propane 9 g ・ dextran (average molecular weight 39,000) 18.5 g ・ potassium polystyrene sulfonate (average molecular weight 60 10,000) 1.8 g-Compound (E-1) 3.4 mg-Compound (E-2) 4.8 g-Snowtex C (Nissan Chemical Co., Ltd.) 29.1 g-Gelatin The total amount applied to one side is 2 It was adjusted to be 0.4 g / m ² . -Adjustment was made so as to be a hardening agent (1,2-bis (vinylsulfonylaceto swelling ratio 230 amide) ethane).

[0039]

[Chemical 6]

(Preparation of Surface Protective Layer Coating Solution) The surface protective layer coating solution was prepared so that each component had the following coating amount.・ Gelatin 0.966 g / m ²・ Poly sodium acrylate (average molecular weight 400,000) 0.023 ・ Compound (P-1) 0.013 ・ Compound (P-2) 0.045 ・ Compound (P-3) 0 0.0065 compound (P-4) 0.003 compound (P-5) 0.001 compound (P-6) 0.0012 polymethylmethacrylate (average particle size 3.7 μm) 0.087 proxel 0 0.0005 (adjusted to pH 7.4 with NaOH)

[0041]

[Chemical 7]

(Preparation of Support) (1) Preparation of Dye K for Undercoat Layer The following dyes were ball milled by the method described in JP-A-63-197943.

[0043]

[Chemical 8]

434 ml of water and Triton X200
(Registered trademark) surfactant (TX-200 (registered trademark))
And 791 ml of a 6.7% aqueous solution of was placed in a 2 liter ball mill. 20 g of dye were added to this solution. 400 ml of zirconium oxide (ZrO) beads (2 mm diameter) were added and the contents were milled for 4 days. After this, 160 g of 12.5% gelatin was added. After defoaming, Zr by filtration
The O beads were removed. When the obtained dye dispersion was observed, the particle size of the crushed dye was 0.37 μm.
Further, a centrifugation operation was performed to remove dye particles having a size of 0.9 μm or more. Thus, Dye Dispersion K was obtained. (2) Preparation of support Corona discharge treatment was performed on a polyethylene terephthalate film having a thickness of 183 μm that was biaxially stretched, and the first undercoat liquid having the following composition was applied at a coating amount of 5.1 cc / m ^2. Was coated with a wire bar coater and dried at 175 ° C. for 1 minute. Next, a first undercoat layer was similarly provided on the opposite surface. The polyethylene terephthalate used was one containing 0.04 wt% of the dye having the following structure.

[0045]

[Chemical 9]

-Butadiene-styrene copolymer latex solution (solid content 40%, butadiene-styrene weight ratio = 31/36) 7.9 cc-2,4-dichloro-6-hydroxy-s-triazine sodium salt 4% solution 20.5 cc-Distilled water 900.5 cc * The following emulsifying dispersants were used in the latex solution.

[0047]

[Chemical 10]

A second undercoat layer having the following composition was coated on each of the above-described first undercoat layers one by one so that the coating amount would be the amount described below, and both sides at 150 ° C. by a wire bar coater system. Applied and dried.・ Gelatin 160 mg / m ²・ Dye Dispersion K (26 mg / m ² as dye solid content)

[0049]

[Chemical 11]

(Preparation of photographic material) On the support prepared as described above, the above emulsion layer and the surface protective layer were coated on both sides by the simultaneous extrusion method. The coated silver amount per side is 1.75.
It was set to g / m ² . Thus, samples 1 to 7 were obtained.

(Evaluation of Photographic Performance) The photographic material was exposed for 0.05 seconds from both sides using an X-ray orthoscreen HR-4 manufactured by Fuji Photo Film Co., Ltd. After exposure
The following processing was performed and sensitivity was evaluated. The sensitivity was based on Sample 1, and indicated by the reciprocal of the ratio of the exposure dose that gives a density of 1.0 in addition to fogging.

(Processing) <Automatic developing machine> ... SRX-501 manufactured by Konica Corporation
(The drive motor and gears were modified to increase the transport speed. <Developer concentrate> Potassium hydroxide 56.6 g Sodium sulfite 200 g Diethylenetriaminepentaacetic acid treatment 6.7 g Potassium carbonate 16.7 g Boric acid 10 g Hydroquinone 83.3 g Diethylene glycol 40 g 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone 22.0 g 5-methylbenzotriazole 0.2 g Compound (D-1) 0.6 g Water to 1 liter (adjusted to pH 10.60) ).

[0053]

[Chemical 12]

<Fixing solution concentrate> Ammonium thiosulfate 560 g Sodium sulfite 60 g Ethylenediaminetetraacetic acid / disodium dihydrate 0.10 g Sodium hydroxide 24 g Water is adjusted to 1 liter (pH is adjusted to 5.10 with acetic acid).

When the development processing was started, each tank of the automatic developing machine was filled with the following processing solutions. Developing tank: 333 ml of the above concentrated developer solution, 667 ml of water and 10 ml of a starter containing 2 g of potassium bromide and 1.8 g of acetic acid were added to adjust the pH to 10.25. Fixing tank: 200 ml of the above concentrated fixing solution and 800 ml of water The processing speed ... Dry to Dry was adjusted to a predetermined time. Development temperature ・ ・ ・ 35 ℃ Fixing temperature ・ ・ ・ 32 ℃ Drying temperature ・ ・ ・ 45 ℃ Replenishing amount ・ ・ ・ Developer 22 ml / 10 × 12 inches Fixer 30 ml / 10 × 12 inches

(Evaluation of Development Progression) The above-mentioned evaluation of photographic property was carried out at processing speeds of Dry to Dry of 30 seconds and 45 seconds of the automatic developing machine, and the sensitivities of both were compared. The results are shown in Table 1.

(Evaluation of natural aging) 50 ° C. 68% inside
The coated sample was placed in a closed container kept at 10 ° C. for 5 days (forced aging). This sample and a sample for comparison (stored in a light-shielding container at room temperature) were subjected to the same treatment as that used for the evaluation of photographic properties, and the density of the fogging portion was measured. The natural aging property was evaluated as a fog increase rate. The rate of increase in fog was 100 times the value obtained by subtracting the (fog density of the comparative sample) from the (fog density of the sample forcibly aged), and dividing the value by the (concentration when all silver halide was developed). The lower the fog increase rate, the better the natural aging property. The results are shown in Table 1.

(Quantification of thiocyanate compound) It was determined according to 1 and 2 (quantification of thiocyanate ion in the emulsion before coating) of the thiocyanate compound. That is, to an emulsion containing 1.5 × 10 ^-2 mol of silver halide, 10 cc of a 1% KBr aqueous solution (when quantifying thiocyanate ion in the emulsion) or distilled water (when quantifying thiocyanate ion in the binder) is used. In addition, the mixture was stirred at 40 ° C for 30 minutes. Then, centrifugation was performed at 10,000 rpm for 10 minutes using Hitachi Centrifuge 20RP-5. After diluting the supernatant liquid 100 times, it was subjected to external filtration using an air press 30 manufactured by Tosoh Corporation. Next, the chromatographic measurement of the filtrate was performed using the CP system manufactured by Tosoh Corporation below. Column; TS IC-Anion SW column temperature; 40 ° C. detector; UV detector (210 nm) eluent; 7.5 mM Na ₂ HPO ₄ and 7.5 mM
Solution containing NaH ₂ PO ₄ (pH 7.0) Flow rate; 0.7 ml / min Calibration curve; 0.1 ppm to 10 ppm potassium thiocyanate aqueous solution.

[0059]

[Table 1]

The results are shown in Table 1. The sensitivity is 45 for sample 1.
It was shown as a relative value with the sensitivity at the time of second processing being 100. It can be seen that when the amount of thiocyanate ion incorporated is 2 mmol / molAg or more, the sensitivity is high and the development progresses rapidly (compared with sample 1 and other samples). However, when the content of the thiocyanic acid compound in the binder was large (Sample 3) and the amount of the particle surface was large (Sample 5), the natural aging property was poor, which was a problematic level for practical use. By adjusting the amount on the surface of the particles and the amount in the binder as in the present invention, a sample having excellent sensitivity and development progress and good natural aging was obtained. Also in the sample according to the present invention, it was found that the method of increasing the pBr when introducing potassium thiocyanate and decreasing the uptake ratio with respect to the added amount is more preferable from the viewpoint of natural aging (sample. (Comparison of 2 and 4).

Claims (3)

[Claims] 1. The silver halide grain contained in the silver halide emulsion is silver iodobromide, and the amount of the thiocyanic acid compound present on the surface of the silver halide grain is 2 per mol of silver.
It is not less than × 10 ^-3 mol and not more than 2 × 10 ^-2 , and the amount of the thiocyanate compound contained in the binder of the silver halide emulsion is not more than 3.0 × 10 ^-3 mol per mol of silver. A silver halide emulsion for photography characterized by. 2. A silver halide photographic light-sensitive material having at least one silver halide emulsion layer on a support,
The silver halide grains in the layer are silver iodobromide, and the amount of the thiocyanic acid compound present on the surface of the silver halide grains is 2 × 10 ⁻³ mol or more and 2 × 10 ⁻² mol per mol of silver. And the amount of the thiocyanic acid compound contained in the binder of the silver halide emulsion layer is 3.0 × 10 ⁻³ mol or less per 1 mol of silver. .. 3. The silver halide photographic light-sensitive material according to claim 1 or 2, wherein the content of the thiocyanic acid compound in the silver halide emulsion layer is 20% or less based on the added amount. Alternatively, a method for producing a silver halide emulsion for photography.