JPH10206995A - Silver halide photographic sensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a silver halide photographic sensitive material which shows increased sensitivity without fog and has excellent storage stability by incorporating silver halide particles sensitized by at least one specified compd. into at least one silver halide emulsion layer. SOLUTION: This silver halide photographic sensitive material has at least one photosensitive silver halide emulsion layer on a supporting body, and at least one silver halide emulsion layer contains silver halide particles sensitized by at least one kind of compd. expressed by formula. In the formula, A is a nitrogen-contg. heterocyclic residue with substitution of a mercapto group, nitrogen-contg. heterocyclic residue containing 4 to 5 nitrogen atoms which constitute the ring, triazine cyclic residue or benztriazol ring residue, R<1> , R<2> and R<3> are independently hydrogen atoms, alkyl groups, alkenyl groups, aryl groups or heterocyclic groups, and R<2> and R<3> may be bonded to form a heteroring.

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 more particularly to a silver halide photographic material which is chemically sensitized by a specific sulfur compound, has high sensitivity, has low fog, and has improved photographic characteristics during storage. The present invention relates to a silver halide photographic material (hereinafter, also referred to as a "photosensitive material").

[0002]

2. Description of the Related Art Usually, silver halide emulsions (hereinafter, also referred to as "emulsions") are subjected to various chemical sensitization treatments in order to increase sensitivity. As one of the typical methods, a method of increasing the sensitivity by adding a small amount of sulfur or a sulfur compound to an emulsion layer to generate silver sulfide is known as a sulfur sensitization method. The most basic of them. Also, a reduction sensitization method using an appropriate reducing agent, a noble metal sensitization method using a noble metal such as gold or iridium, and the like are known. Furthermore, by combining these sensitization methods,
It is also known that the sensitivity of emulsions can be further increased.

As a sulfur sensitization method, for example, US Pat.
410,689, 3,501,313, West German Patent 1,422,869, JP-B-49-20533.
And JP-A-55-45016.

In recent years, there has been an increasing demand for light-sensitive materials to reduce the processing time and the amount of coated silver, and accordingly, it has been required to further increase the sensitivity of silver halide emulsions.

[0005] Among the sulfur sensitization methods, JP-A-55-450 discloses
The sensitizing technique described in No. 16 has a larger sensitizing effect than the known sulfur sensitizing method.

However, these sensitizing techniques tend to be accompanied by fogging, and have a drawback that fogging occurs when stored over time, causing a change in photographic properties, and cannot be said to be a technique that is sufficiently satisfactory. In the current situation.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a silver halide photographic light-sensitive material whose sensitivity is improved without fogging and which has excellent storage stability.

[0008]

The above objects of the present invention have been attained by the following constitutions.

In a silver halide photographic material having at least one light-sensitive silver halide emulsion layer on a support, at least one of the silver halide emulsion layers is a compound represented by the following formula (I): A silver halide photographic material comprising silver halide grains sensitized by at least one of the following.

[0010]

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In the formula, A is a nitrogen-containing heterocyclic residue substituted with a mercapto group, a nitrogen-containing heterocyclic residue containing 4 to 5 nitrogen atoms as ring constituent atoms, a triazine ring residue or a benzotriazole ring residue. And R ₁ , R ₂ and R ₃ each represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heterocyclic group. R ₂ and R ₃ may combine to form a heterocyclic ring.

Hereinafter, the present invention will be described more specifically.

First, the compound represented by formula (I) will be described.

In the general formula (I), examples of the nitrogen-containing heterocyclic residue substituted by the mercapto group represented by A include mercaptotetrazole, mercaptotriazole, mercaptooxazole, mercaptothiazole, mercaptobenzoselenazole, mercaptothiadiazole, and mercaptooxadiazole. Each ring residue such as diazole, mercaptotriazine, mercaptobenzoxazole, mercaptobenzothiazole, mercaptobenzimidazole, mercaptoadenine, mercaptoguanine and the like can be mentioned.

A represents 4 nitrogen atoms as ring constituent atoms.
Examples of the nitrogen-containing heterocyclic residue containing up to 5 include each ring residue such as tetrazole, tetrazaindene, adenine, azaadenine, and guanine.

A also represents a triazine ring residue or a benzotriazole ring residue.

These heterocyclic residues represented by A include an alkyl group, an alkoxy group, an aryl group, a hydroxyl group,
It may be substituted with various substituents such as a carboxyl group and a halogen atom.

Examples of the alkyl group represented by R ₁ , R ₂ and R ₃ include methyl, ethyl, propyl, i-propyl, butyl, i-butyl and sec-butyl, and the alkenyl group is allyl. , Crotyl and the like, and the alkynyl group includes a group such as propargyl. Examples of the aryl group include groups such as phenyl and naphthyl, and examples of the heterocyclic group include oxazolyl,
Groups such as thiazolyl, pyridyl and pyrimidinyl;

The heterocyclic ring which can be formed by combining R ₂ and R ₃ includes rings such as pyrrolidine, piperazine, piperidine and morpholine.

The alkyl, alkenyl, alkynyl, aryl or heterocyclic groups represented by R ₁ , R ₂ and R ₃ and R
_{Heterocycle 2} and R ₃ are formed by bonding may further have a substituent, examples of the substituent include an alkyl group, a hydroxyl group, an alkoxy group, a carboxyl group, an aryl group or a halogen atom.

Hereinafter, specific examples of the compound represented by formula (I) (referred to as the sulfur compound of the present invention) will be given, but the invention is not limited thereto.

[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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Next, a synthesis example of the above sulfur compound will be described.

Synthesis Example 1 (Synthesis of Exemplified Compound 1) 1.18 g of 1- (3-aminophenyl) -5-mercaptotetrazole hydrochloride, ethyl isothiocyanate 0.1 g
87 g and 1,01 g of triethylamine were added to 50 ml of acetonitrile, and the mixture was refluxed for 15 hours. 25 ml of reaction product
The mixture is concentrated to 50 ml, precipitated by adding 50 ml of water, filtered and washed with water. The cake collected by filtration is put into 50 ml of water, and 2 m of hydrochloric acid is added.
Then, the mixture is heated to 90 ° C., kept warm for 10 minutes, cooled to 70 ° C., filtered and washed with water. Cake is acetonitrile 60m
and cooled at 70 ° C., and after cooling, some insolubles are filtered off. After adding 50 ml of water to the filtrate and leaving it for a while, a solid precipitates out. Therefore, the solid was collected by filtration, and the cake was dried under reduced pressure at 60 ° C. to obtain 1.7 g of the desired product (60% yield).

Synthesis Example 2 (Synthesis of Exemplified Compound 15) 1.35 g of adenine, 1.7 of ethyl isothiocyanate
4 g in 90 ml of dimethylformamide at 90-95 ° C
For 20 hours. Further, the reaction was carried out at 120 to 125 ° C. for 20 hours. After cooling, 100 ml of water was added to the reaction solution, and the mixture was allowed to stand for 1 week, whereupon needle-like crystals were precipitated. Filter the crystals,
After washing with water, the precipitate was dried under reduced pressure at 60 ° C.
% Yield).

The other sulfur compounds of the present invention can be synthesized in a similar manner.

In addition to the sulfur compound of the present invention, a water-soluble gold compound is used in an amount of 1 × 10 ^-9 to 1 × 10 ⁹ per mol of silver halide.
By using ^-4 moles together, higher sensitivity and lower fog can be achieved.

Useful water-soluble gold compounds include, for example, US Pat. Nos. 2,399,083 and 2,642,361.
Chloroauric acid, potassium aurate, as described in
Examples include potassium auricyanide, potassium aurithiocyanate, gold sulfide, potassium chloroaurate, gold selenide and the like, and the following compounds.

[0033]

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The sulfur compound of the present invention may be used as a solution of water or a water-miscible organic solvent such as methanol, ethanol, fluorinated alcohol, phenoxyethanol or the like, alone or as a mixed solvent, or as a microcrystalline dispersion during emulsion production. , But is preferably added at the start of chemical ripening. The addition amount of the sulfur compound is not uniform depending on the type of the emulsion, the conditions used, and the like, but is usually in the range of 3 × 10 ^-8 to 1 × 10 ^-3 mol per mol of silver halide, and is preferably. It is 1 × 10 ^{−7 to} 5 × 10 ⁻⁴ mol.

The pAg (logarithm of the reciprocal of silver ion concentration) during chemical ripening is preferably 8.0 to 11.0.

At the time of chemical ripening, other chemical sensitizers can be used in combination. Examples of chemical sensitizers that can be used in combination include, for example, U.S. Pat. Nos. 2,419,973 and 2,487,85.
No. 0, 2,518,698, 2,521,925
Nos. 2,521,926 and 2,694,637
Compounds described in US Pat. Nos. 2,983,610 and the like, and reducing substances such as stannous chloride, US Pat.
48,060, 2,566,245, 2,56
No. 6,263, etc., salts of noble metals such as platinum, palladium and rhodium.

The silver halide emulsion used in the present invention is:
Any halogen composition such as silver bromide, silver iodobromide, silver chloride, silver chlorobromide, silver chloroiodobromide, or silver iodochloride may be used.
Simmy & Physic Photographics by P. Grafkides (PaulMontel, 1967)
Year), Photographic Emulsion Chemistry by GF Duffin (The Focal)
Press, 1966), Making and Coating Photographic Emulsion (The Focal) co-authored by V. El Jerikmmann and others.
Press, 1964), JP-A-51-39027, JP-A-55-142329, JP-A-58-113928, JP-A-54-48521, and JP-A-5-48521.
No. 8-49938, No. 60-138538, etc., and can be prepared by the method described in the Abstracts of the 58th Annual Meeting of the Photographic Society of Japan, 1983, page 88. That is, any of an acidic method, a neutral method, an ammonia method and the like may be used, and a method of reacting a soluble silver salt and a soluble halide salt includes a one-sided mixing method, a double-mixing method, a combination thereof, or a method in which grains are mixed with silver ions. Either a method of forming under excess (reverse mixing method), a method of supplying a soluble silver salt and a soluble halogen salt to a fine seed crystal and growing the seed crystal may be used.

The silver halide grain size distribution of the emulsion may be either narrow or wide, but is preferably monodisperse with uniform grain sizes. Specifically, when the width of the distribution is defined by the relative standard deviation (coefficient of variation) expressed by (standard deviation of particle size / average particle size) × 100 = width (%) of particle size distribution, 25% or less Is preferred, more preferably 20% or less, particularly preferably 15% or less.

The average grain size of the silver halide grains to be used is not particularly limited, but is 0.05 to 2.0 μm, preferably 0.1 to 1.2 μm.

The silver halide grains contained in the emulsion may have a regular shape such as a cubic, octahedral or tetradecahedral shape, an irregular shape such as a flat twin, or both. It may be mixed. The mixing ratio at the time of mixing and using the silver halide grains may be any ratio as long as the effects of the invention are not lost.
10:90 is preferred, and more preferably 75: 25-2.
5:75.

Twins are silver halide crystals having one or more twin planes in one grain, and the twins are classified according to the report by Klein and Moiser. (Photographhishhe
Korespondenz) Vol. 99, p. 99, ibid.
00, p. 57.

The twin grains used in the present invention mainly have an even number of parallel twin planes. These twin planes may or may not be parallel to each other, but are particularly preferred. Has two twin planes.

The average value (average aspect ratio) of the ratio of grain diameter / thickness (aspect ratio) is used for tabular silver halide grains.
Is 2 or more, and the average aspect ratio is preferably 2 to 10, more preferably 3 to 8. In these tabular silver halide grains, the outer wall of the crystal is substantially almost (1).
It may be composed of 11) plane or composed of (100) plane. Further, it may have both the (111) plane and the (100) plane. In this case, 50% or more of the particle surface is the (111) plane, more preferably 60 to 90% is the (111) plane, and particularly preferably 70 to 95% is the (111) plane. It is preferable that the plane other than the (111) plane is mainly the (100) plane. This plane ratio is determined by utilizing the difference in the dependence of the adsorption of the sensitizing dye between the (111) plane and the (100) plane on the adsorption of the sensitizing dye.
ani; Imaging Sci. , 29,165
(1985) ".

Tabular silver halide grains preferably have a small thickness distribution. Specifically, when the width of the distribution is defined by (standard deviation of thickness / average thickness) × 100 = width (%) of thickness distribution, it is preferably 25% or less, more preferably 20% or less. %, Particularly preferably 15% or less.

Further, the distribution of the halogen content of each grain in the tabular silver halide grain emulsion is preferably small. Specifically, (standard deviation of halogen content / average halogen content) ×
When the width of the distribution is defined by 100 = the width (%) of the halogen content, the width is preferably 25% or less, more preferably 20% or less, and particularly preferably 15% or less.

The tabular silver halide grains are preferably hexagonal. Hexagonal tabular grains (hereinafter sometimes referred to as hexagonal tabular grains) refer to the main plane ｛(111)
The shape of the surface｝ is hexagonal and the maximum adjacent ratio is 1.0
~ 2.0. Here, the maximum adjacent side ratio is a ratio of the length of the side having the maximum length to the length of the side having the minimum length forming the hexagon. If the hexagonal tabular grains have a maximum adjacent side ratio of 1.0 to 2.0, it is preferable that the corners are rounded, and the corners are further removed.
It is also preferred that the tabular grains are substantially circular. The length of a side having a rounded corner is represented by the distance between the intersection of the straight line portion of the side and the line extending from the straight line of the adjacent side.

Each side forming the hexagon of the hexagonal tabular grain is:
It is preferable that at least half thereof be substantially a straight line, and it is more preferable that the adjacent side ratio be 1.0 to 1.5.

The dislocation of halogenated grains is described, for example, in J. Am. F.
Hamilton; Photo. Sci. Eng. , 57
(1967) and T.W. Shiozawa; Soc.
Photo. Sci. Japan, 35, 213 (197)
It can be observed by a direct method using a transmission electron microscope at a low temperature as described in 2). That is, the silver halide grains taken out from the emulsion so as not to apply enough pressure to generate dislocations on the grains are placed on a mesh for electron microscopic observation, and the sample is prepared so as to prevent damage (printout, etc.) by electron beams. Observation is performed by a transmission method in a state of cooling. At this time, the thicker the particle, the more difficult it is for the electron beam to pass through. Therefore, it is better to use a high-pressure electron microscope (200 kV or more for a particle having a thickness of 0.25 μm) to observe more clearly. Can be. From the photographs of the particles obtained by such a method, the position and number of dislocations for each particle can be determined.

It is desirable that the dislocation position is generated in a region from 0.58 L to 1.0 L from the center of the halogenated grain toward the outer surface, but more preferably 0.80 L
It occurs in the region of .about.0.98 L. The direction of the dislocation line is approximately from the center to the outer surface, but often meanders. The center of the silver halide grains is defined by dispersing silver halide microcrystals in methacrylic resin and solidifying the same as in the method described in the abstract of Inoue et al. Ultrathin sections with a microtome, with the largest cross-sectional area and 9
Focusing on a section sample having a cross-sectional area of 0% or more, this is the center of a circle when a circumscribed circle that is the minimum with respect to the cross section is drawn.

In the present invention, the distance L from the center to the outer surface is defined as the distance between the point of intersection of the outer periphery of the particle and the center of the circle when a straight line is drawn outward from the center of the circle.

Regarding the number of dislocations, it is preferable that 50% (number) of particles containing one or more dislocations exist.
The higher the ratio (number) of the number of tabular grains having dislocation lines, the better.

In the tabular grains, the particle diameter is a diameter when a projected image of the grains is converted into a circular image having the same area. The projected area of a particle can be determined from the sum of the particle areas.
That is, a silver halide crystal sample distributed on a sample table to such an extent that no grains are overlapped can be obtained by observing the sample with an electron microscope.

The average projected area diameter of a grain is represented by a circle equivalent diameter of the projected area of the grain, and is preferably 0.30 μm or more, more preferably 0.30 to 5 μm, and still more preferably 0.40 to 2 μm. It is. The particle size can be obtained by projecting the particles at a magnification of 10,000 to 70,000 times with an electron microscope and actually measuring the projected area on the print. The average particle diameter phi _i is the measured particle径個number is n, the particles often having a particle size d _i is taken as n _i, can be calculated from the following equation.

[0054] Mean particle diameter _{(φ i) = (Σn i} d i) / n ( number of measured grains and is indiscriminately more than 1,000) of the grain thickness, a sample from an oblique by electron microscopy Obtained by observation. The preferred thickness of the tabular grains of the invention is from 0.03 to 1.0 μm, more preferably from 0.05 to 0.5 μm.

The ratio (b / a = aspect ratio) of the longest distance (a) between two or more parallel twin planes of the silver halide grains and the thickness (b) of the grains is preferably 5 or more. The ratio of the number of such particles is preferably 50% or more.

The distance between twin planes (a) can be determined as follows. That is, the section was observed using the above-mentioned transmission electron microscope, and arbitrarily selected 100 or more tabular silver halide grains exhibiting a cross section cut almost perpendicularly to the main plane. ) Is measured, and the average is obtained. The average value of (a) is preferably 0.008 μm or more, and more preferably 0.010 to 0.05 μm. In addition, it is necessary that (a) is within the above-mentioned value range and the coefficient of variation must be 35% or less, and preferably 30% or less.

Further, taking into account the factors of the aspect ratio and the grain thickness, tabularity represented by the following equation: A = ECD / b ²
Is preferably 20 or more. Here, ECD indicates the average projected diameter (μm) of tabular grains, and (b) indicates the thickness of the grains. Further, the average projected diameter indicates the number average of the diameter of a circle having an area equal to the projected area of the tabular grains.

The silver halide grains used in the present invention are:
A core / shell type structure having at least two layer structures having substantially different halogen compositions in silver halide grains,
It may have a uniform composition, but preferably has a core / shell structure. In this case, the grain center may have a halogen composition region different from that of the core. In such a case, the halogen composition of the seed grains can be any combination of silver bromide, silver iodobromide, silver chloroiodobromide, silver chlorobromide, silver chloride and the like.

A method for producing silver halide grains having a core / shell type structure is described in, for example, West German Patent 1,169,29.
0, British Patent 1,027,146, JP-A-57-1
No. 5423, Japanese Patent Publication No. 51-1417, etc. can be employed.

The average silver iodide content of the silver halide emulsion used in the present invention is preferably 6 mol% or less, more preferably 0.1 to 1.5 mol%. Of the grains having a layer structure with a different halogen composition, grains having a high silver iodide layer inside the grains and a low silver iodide layer or a silver bromide layer on the outermost layer are preferred. At this time, the silver iodide ratio of the inner layer (core) having the highest silver iodide content is preferably 2.5 mol% or more, more preferably 5 mol% or more. The content of silver iodide is preferably 0 to 5 mol%, more preferably 0 to 3 mol%, and the silver iodide content of the core is at least 3 mol% or more higher than the silver iodide content of the shell. preferable. The silver iodide distribution of the core is usually uniform,
It may have a distribution. For example, as the concentration goes from the center to the outside, the concentration may become higher, or the intermediate region may have a maximum or minimum concentration.

In the present invention, so-called halogen conversion type (conversion type) particles may be used. The halogen conversion amount is preferably from 0.2 to 2.0 mol% based on the silver amount, and the conversion may be performed during physical ripening or after physical ripening. As a halogen conversion method, usually, an aqueous halogen solution or silver halide fine particles having a solubility product with silver smaller than the halogen composition on the grain surface before the halogen conversion is added. The particle size at this time is preferably 0.2 μm or less, more preferably 0.02 to 0.1 μm.

The silver iodide content and the average silver iodide content of silver halide grains were determined by an EPMA method (Electron Pr).
ob Micro Analyzer). According to this method, a sample in which emulsion grains are well dispersed so as not to be in contact with each other is prepared, and element analysis of a portion smaller than X-ray analysis by electron beam excitation for irradiating an electron beam can be performed. By this method, the halogen composition of each grain can be determined by determining the characteristic X-ray intensity of silver and iodine emitted from each grain. If the silver iodide content is determined for at least 100 grains by the EPMA method, the average silver iodide content can be determined from the average thereof.

Further, during the process of forming and / or growing the silver halide grains, cadmium salts, zinc salts, lead salts, thallium salts, iridium salts (including complex salts),
At least one metal ion selected from a rhodium salt (including a complex salt) and an iron salt (including a complex salt) can be added, and these metal elements can be contained inside the particles and / or in the particle surface layer. By placing in a suitable reducing atmosphere, a reduction sensitizing nucleus can be provided inside the grains and / or on the surface of the grains.

The effect of the reducing agent added at a desired point in time of particle formation can be improved by adding an oxidizing agent such as hydrogen peroxide (water) and its adduct, peroxoacid salt, ozone, and I2 at a desired point in time. It is preferable to deactivate and suppress or stop the reducing agent. The oxidizing agent may be added at any time from when the silver halide grains are formed to before the addition of a gold sensitizer (or a chemical sensitizer if no gold sensitizer is used) in the chemical sensitization step.

In the silver halide photographic emulsion, unnecessary soluble salts may be removed at the end of the growth of the silver halide grains, or may be kept contained. When removing the salts, use a Research Disclosure (Resea).
rch Disclosure (hereinafter abbreviated as RD) N
o. It can be performed based on the method described in 17643 No. II.

In the present invention, each of the 2
More than one kind of silver halide emulsion can be arbitrarily mixed and used.

The hydrophilic protective colloid used for preparing the light-sensitive material includes gelatin used in ordinary emulsions as described in "Products Index", Vol. 92, p. 108, "Vehicles". In addition, gelatin derivatives such as acetylated gelatin and phthalated gelatin, water-soluble cellulose derivatives, and other synthetic or natural hydrophilic polymers are included.

For the photographic material, various techniques and additives known in the art can be used as necessary. For example, in addition to the photosensitive emulsion layer, auxiliary layers such as a protective layer, a filter layer, an antihalation layer, a crossover light-cutting layer, and a backing layer can be provided. Agents, noble metal sensitizers, photosensitive dyes, supersensitizers,
Couplers, high boiling solvents, antifoggants, stabilizers, development inhibitors, bleach accelerators, fixing accelerators, color mixture inhibitors, formalin scavengers, color toning agents, hardeners, surfactants, thickeners, plasticizers, A slipping agent, an ultraviolet absorber, an anti-irradiation dye, a filter light-absorbing dye, a fungicide, a polymer latex, a heavy metal, an antistatic agent, a matting agent and the like can be contained by various methods.

The above-mentioned additives are described in more detail in RD17643 (December 1978), p.
Pp. 29-XXI, RD 18431 (August 1979
Mon), RD18716 (November 1979), 648-
651 and RD308119 (December 1989),
It is described in page 996, paragraphs III-A to 1012, paragraphs XXI-E.

Examples of the support which can be used for the light-sensitive material include the aforementioned RD17643, page 28 and RD3
08119, 1009 pages and Product Licensing
Index, Vol. 92, p. 108, “Support
s ".

Suitable supports include cellulose triacetate, cellulose nitrate, polyesters such as polyethylene terephthalate and polyethylene-2,6-naphthalate, polyolefins such as polyethylene, polystyrene, baryta paper, paper laminated with polyethylene, etc.
Glass, metal and the like can be mentioned. In order to improve the adhesion of the coating layer, the surfaces of these supports are subjected to a base treatment such as a corona discharge treatment, an ultraviolet irradiation, and the setting of a subbing polymer adhesive layer.

Examples of the light-sensitive material of the present invention containing the above-mentioned silver halide emulsion include black-and-white light-sensitive materials (medical light-sensitive material, printing light-sensitive material, microfilm light-sensitive material, negative film light-sensitive material for general photography, etc.), color light-sensitive materials and the like. It can be applied to materials (color negative sensitive material, color reversal sensitive material, color print sensitive material, etc.), photosensitive material for diffusion transfer, photothermographic material and the like.

For developing the light-sensitive material of the present invention, for example, the Product Licensing Index, Vol.
See “Process” on page 110; H. The Theory of the Photographic by James
Process 4th edition (The Theory of the
Photographic Process, fou
rth Edition) pp. 291-334 and Journal of the American Chemical Society (J. Am. Chem. Soc.) 73, 3100 (1951). .

[0074]

EXAMPLES Specific examples of the present invention will be described below, but the embodiments of the present invention are not limited to these examples.

Example 1 <Preparation of seed emulsion-I> Seed emulsion-I was prepared as follows.

A1 ossein gelatin 24.2 g water 9657 ml 10% ethanol solution of surfactant SA-1 6.78 ml potassium bromide 10.8 g 10% nitric acid 114 ml B1 2.5N silver nitrate aqueous solution 2825 ml C1 potassium bromide 824 g iodide Potassium 23.5 g Finished to 2825 ml with water D1 1.75 N aqueous potassium bromide solution Silver potential control amount below SA-1: Polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt JP-B-58-58288, 58 at 35 ° C -5828
Using the mixing stirrer described in No. 9, 464.3 ml of each of the solution B1 and the solution C1 was added to the solution A1 by the simultaneous mixing method.
Nucleation was carried out by adding over 5 minutes.

After stopping the addition of the solution B1 and the solution C1, it takes 60 minutes to raise the temperature of the solution A1 to 60 ° C., adjust the pH to 5.0 with a 3% aqueous solution of potassium hydroxide, and again. , Solution B1 and solution C1 by a simultaneous mixing method,
Each was added at a flow rate of 55.4 ml / min for 42 minutes. The silver potential (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) during the temperature rise from 35 ° C to 60 ° C and re-simultaneous mixing with the solutions B1 and C1 was measured using the solution D1.
Control was performed so as to be +8 mV and +16 mV, respectively.

After the addition was completed, the pH was adjusted to 6 with a 3% aqueous potassium hydroxide solution, and immediately desalting and washing were performed.
This seed emulsion accounts for 90% of the total projected area of silver halide grains.
The above description shows that hexagonal tabular grains having a maximum adjacent side ratio of 1.0 to 2.0 were formed, and the average thickness of the hexagonal tabular grains was 0.06 μm and the average grain size (circular diameter conversion) was 0.59 μm. It was confirmed with a microscope. The variation coefficient of the thickness was 40%, and the variation coefficient of the distance between twin planes was 42%.

<Preparation of Em-1> A tabular emulsion having a core / shell structure was prepared using the above seed emulsion-I and the following four kinds of solutions.

A2 ossein gelatin 11.7 g 10% aqueous solution of surfactant SA-1 in ethanol 1.4 ml seed emulsion-I 0.10 mol equivalent Equivalent to 550 ml with water B2 ossein gelatin 5.9 g potassium bromide 6. 2g Potassium iodide 0.8g Finish to 145ml with water C2 Silver nitrate 10.1g Finish to 145ml with water D2 Ossein gelatin 6.1g Potassium bromide 94g Finish to 304ml with water E2 Silver nitrate 137g Finish to 304ml with water Vigorous at 67 ° C The solution B2 and the solution C2 were added to the stirred solution A2 by a double jet method in 58 minutes. Next, D2 solution and E2 solution were added to the same solution by a double jet method for 48 minutes. During this time, the pH was kept at 5.8 and the pAg was kept at 8.7.

After completion of the addition, desalting and precipitation were carried out in the same manner as for seed emulsion-I to obtain an emulsion having a pAg of 8.5 and a pH of 5.85 at 40 ° C. and having an average silver iodide content of about 0.5 mol%. Was.

When the obtained emulsion was observed with an electron microscope, 81% of the projected area was tabular silver halide having an average grain size of 0.96 μm, a grain size distribution of 19%, and an average aspect ratio of 4.5. Particles. The average of the twin plane distance (a) was 0.019 μm, and the variation coefficient of (a) was 28%.
Met.

<Preparation of Em-2 and Em-3> Seed emulsion
Amount of potassium bromide in solution A1 in preparation of I, solution B
1. Addition time of C1, addition temperature, seed emulsion-I in solution A2 in preparation of Em-1, amount of potassium bromide and potassium iodide in solution B2, pAg at the time of addition, addition speed, addition time, addition A core-shell type emulsion having an average iodine content of 1.5 mol% and 2.5 mol%, respectively, in the same manner as Em-1 except that the temperature and the like are changed (the core portion is higher in iodine content than the shell portion). Em-2 and Em-3 (having a high degree of content) were prepared.

Each of the emulsions had an average aspect ratio of about 4.5.
Are tabular grains having the following average characteristics: average particle diameters are 1.02 μm and 0.98 μm, respectively; the dispersion coefficient of the particle diameters is 21% and 22%; and the average twin plane distance (a )
Was 0.24 μm, 0.018 μm, and the variation coefficients of (a) were 30% and 33%.

<Preparation of Seed Emulsion-II> Seed Emulsion-II was prepared as follows.

A3 ossein gelatin 24.2 g water 9657 ml 10% ethanol solution of surfactant SA-1 6.78 ml potassium bromide 10.8 g 10% nitric acid 114 ml B3 2.5N silver nitrate aqueous solution 2825 ml C3 potassium bromide 841 g with water D3 1.75N aqueous solution of potassium bromide D3 1.75N aqueous solution of potassium potential The following silver potential control amount at 42 ° C: JP-B-58-58288, 58-5828
Using a mixing stirrer shown in No. 9
Then, 464.3 ml of each of the solution C3 and the solution C3 were added by a simultaneous mixing method over 1.5 minutes to form nuclei.

After the addition of the solution B3 and the solution C3 was stopped, the temperature of the solution A3 was raised to 60 ° C. over a period of 60 minutes, and the pH was adjusted to 5.0 with a 3% aqueous potassium hydroxide solution. The solution B3 and the solution C3 were added at a flow rate of 55.4 ml / min for 42 minutes by the simultaneous mixing method. This 4
The silver potential (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) during the temperature rise from 2 ° C. to 60 ° C. and re-mixing with the solutions B3 and C3 was measured using the solution D3.
Control was performed so as to be +8 mV and +16 mV, respectively.

After completion of the addition, the pH was adjusted to 6 with a 3% aqueous potassium hydroxide solution, and immediately desalting and washing were performed.
This seed emulsion accounts for 90% of the total projected area of silver halide grains.
The electron microscope shows that the hexagonal tabular grains having a maximum adjacent side ratio of 1.0 to 2.0 as described above were formed, and the average thickness of the hexagonal tabular grains was 0.064 μm and the average grain size (in terms of circular diameter) was 0.595 μm. Confirmed. The variation coefficient of the thickness was 40%, and the variation coefficient of the distance between twin planes was 42%.

<Preparation of Em-4> A tabular pure silver bromide emulsion Em-4 was prepared using Seed Emulsion-II and the following three kinds of solutions.

A4 Ossein gelatin 34.03 g 10% aqueous solution of surfactant SA-1 in ethanol 2.25 ml Seed emulsion-II 1.218 mol equivalent Equivalent to 3150 ml with water B4 1747 g Potassium bromide 1369 g with water C4 silver nitrate Finishing to 4193 ml with 2493 g water The solution A4 was vigorously stirred in a reaction vessel while maintaining the temperature at 60 ° C., and the total amount of the solution B4 and the solution C4 was added thereto over 100 minutes by a double jet method. During this time, the pH was adjusted to 5.8 and p
Ag was kept at 8.8 throughout. Here, solution B4 and solution C4
The addition rate was varied as a function of time to match the critical growth rate. That is, they were added at an appropriate addition rate so as to prevent generation of small particles other than the growing seed particles and to prevent polydispersion by Ostwald ripening.

After the addition was completed, the emulsion was cooled to 40 ° C.
13.8% (by weight) aqueous solution of phenylcarbamoyl group-modified gelatin (substitution rate 90%) as an aggregating polymer agent 18
00 ml was added and stirred for 3 minutes. Then 56% acetic acid
(Weight) An aqueous solution was added to adjust the pH of the emulsion to 4.6, and the mixture was stirred for 3 minutes, allowed to stand for 20 minutes, and the supernatant was drained by decantation. Thereafter, 9.0 liters of distilled water at 40 ° C. was added, and the mixture was stirred and allowed to stand. The supernatant was drained, and 11.25 liters of distilled water was further added. After stirring and allowed to stand, the supernatant was drained. Subsequently, an aqueous gelatin solution and a 10% (by weight) aqueous sodium carbonate solution were added to adjust the pH to 5.80, followed by stirring at 50 ° C. for 30 minutes to redisperse.

After redispersion, the pH was adjusted to 5.80 and p
Ag was adjusted to 8.06. When the obtained emulsion was observed with an electron microscope, the average particle diameter was 1.11 μm and the average thickness was 0.1 μm.
Tabular grains having a size of 25 μm, an average aspect ratio of about 4.5, and a particle size distribution of 18.1% were obtained. The average of the twin plane distance (a) is 0.020 μm, and the variation coefficient of (a) is 3
2%.

Next, the sensitizing effects of the sulfur compounds (sulfur sensitizers) of the present invention were examined using the above emulsions Em-1 to Em-4 as follows.

That is, after each emulsion was heated to 60 ° C., a predetermined amount of spectral sensitizing dye was added as a dispersion of solid fine particles.
Adenine, ammonium thiocyanate and the sensitizers shown in Table 1 were added, and after 60 minutes, a silver iodide fine grain emulsion was added, followed by a total of 2 hours of chemical ripening. At the end of chemical ripening, 4-hydroxy-6-methyl-1,3,3a, 7 is used as a stabilizer.
-A predetermined amount of tetrazaindene (ST-1) was added.
The additives and their amounts (per mole of AgX) are shown below.

Spectral sensitizing dye (SD-1) 2.0 mg Spectral sensitizing dye (SD-2) 120 mg Adenine (stabilizer) 15 mg Ammonium thiocyanate 95 mg Water-soluble gold compound (described in Table 1) 4.0 × 10 ^{− 4} mol / mol silver Sulfur compound (described in Table 1) 5.0 × 10 ^-4 mol / mol silver fine silver iodide particles 280 mg Stabilizer (ST-1) 50 mg

[0096]

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The dispersion of the solid fine particles of the spectral sensitizing dye was prepared according to the method described in JP-A-5-297496. That is, a predetermined amount of the spectral sensitizing dye is added to water whose temperature has been previously adjusted to 27 ° C., and 3,500 r.
Obtained by stirring at pm for 30-120 minutes.

The average iodide content of the outermost surface of the silver halide grains contained in the emulsion Em-4 was about 4 mol% by the addition of the silver iodide fine grains.

To the emulsion thus sensitized, the following additives were added to prepare an emulsion layer coating solution, and at the same time, a protective layer coating solution was prepared.

The support was a glycidyl methacrylate / methyl acrylate / butyl methacrylate copolymer (50:10:40 wt.) On both sides of a polyethylene terephthalate film base for X-rays having a thickness of 175 μm and a blue color of 0.15. %) Was dispersed so as to have a concentration of 10% by weight, and an aqueous dispersion of the copolymer was dispersed and used as an undercoat liquid.

The following dye layers are coated on both sides of the support, and then the emulsion layer coating solution and the protective layer coating solution are simultaneously coated on both sides using two slide hopper coaters so that the following coating amounts are obtained. Coating and drying were performed to produce photosensitive material samples 1 to 16.

The amount of the additive in each layer indicates the amount (one side) per 1 m ² of the sample. The amount of silver applied was adjusted so as to be 1.6 g / m ² on one side.

First layer (dye layer) Dye F-1 (solid fine particle dispersion) 180 mg Gelatin 0.2 g Surfactant (SA-2) 5 mg Latex (L) 0.2 g Hardener (H-1) 5 mg Colloidal silica (average particle size: 0.014 μm) 10 mg Formaldehyde (hardener) 2 mg Second layer (emulsion layer) The following various additives were added to each emulsion obtained above.

Additive (T-1) 0.5 mg Additive (T-2) 5 mg t-butyl-catechol 130 mg polyvinylpyrrolidone (molecular weight 10,000) 35 mg styrene-maleic anhydride copolymer 80 mg sodium polystyrene sulfonate 80 mg Trimethylolpropane 350 mg Diethylene glycol 50 mg Nitrophenyl-triphenyl-phosphonium chloride 20 mg Resorcin-4-ammonium ammonium sulfonate 500 mg 2-Mercaptobenzimidazole-5-sodium sulfonate 5 mg Additive (T-3) 0.5 mg C ₄ H ₉ OCH _{2 CH (OH) CH 2 N} (CH 2 COOH) 2 350mg compound (ST-2) 5mg compound (ST-3) 0.2mg compound (ST-4) 5mg compound (ST-5) 0.2 g Colloidal silica 0.5g Latex (L) 0.2 g Dextrin (average molecular weight 1000) 0.2 g 5-methylbenzotriazole 0.7mg however, was adjusted to 1.0 g / m ² as gelatin.

Third layer (protective layer) Gelatin 0.8 g Stabilizer (ST-1) 20 mg Matting agent composed of PMMA (area average particle size 7.0 μm) 50 mg Formaldehyde (hardening agent) 20 mg Hardening agent (H- 1) 10 mg Glyoxal (hardener) 36 mg Latex (L) 0.2 g Polyacrylamide (average molecular weight 10,000) 0.1 g Sodium polyacrylate 30 mg Additive (SI-1) 20 mg Surfactant (SA-3) 12 mg Interface Surfactant (SA-4) 2 mg Surfactant (SA-5) 7 mg Additive (T-4) 15 mg C ₁₁ H ₂₃ CONH (CH ₂ CH ₂ O) ₅ H (surfactant) 50 mg Surfactant (SA) -7) 5 mg C ₉ F ₁₉ O (CH ₂ CH ₂ O) ₁₁ H 3 mg C ₈ F ₁₇ SO ₂ N (CH ₂ CH ₂ O) ₁₅ H 2 mg C ₈ F _{17 SO 2 (C 3 H 7)} N (CH 2 CH 2 O) 4 (CH 2) 4 SO 3 Na1mg SA-2: Sodium dodecylbenzenesulfonate H-1: 2,4-dichloro-6-hydroxy -s- Triazine sodium T-2: 2,6-di (hydroxyamino) -4-diethylamino-s-triazine ST-2: 1- (3-sulfophenyl) -5-mercaptotetrazole sodium salt ST-4: 1- (3-carboxyphenyl) -5-mercaptotetrazole ST-5: 2,6-dimercapto-4-anilino-s-
Triazine / monosodium PMMA: polymethyl methacrylate SA-4: p-nonylphenol / ethylene oxide 1
2-mol adduct SA-5: sulfosuccinate di (2,2,3,3,4,4,
5,5,6,6,7,7-dodecylfluoroheptyl)
Sodium salt SA-7: di (2-ethylhexyl) sulfosuccinate sodium salt

[0106]

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[0107]

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Next, each sample obtained as described above was stored under two kinds of conditions (condition A: 23 ° C./55% RH, condition B: 40 ° C./80% RH) for 5 days, The photographic characteristics were evaluated.

The evaluation method was as follows: two samples of intensifying screen KO-2
50 (manufactured by Konica Corp.), and a tube voltage of 80 kVp, a tube current of 100 mA, and an X of 0.05 second through an aluminum wedge.
A line was irradiated and exposed. Next, the automatic developing machine SRX-50
2 (manufactured by Konica Corp.) and processed with a developer and a fixer having the following formulation.

(Developer formulation) Part-A (for finishing 12 liters) Potassium hydroxide 450 g Potassium sulfite (50% solution) 2280 g Diethylenetriaminepentaacetic acid 120 g Sodium bicarbonate 132 g 5-Methylbenzotriazole 1.2 g 1-phenyl- 5-mercaptotetrazole 0.2 g hydroquinone 340 g Add water to make 5000 ml Part-B (for finishing 12 liters) Glacial acetic acid 170 g Triethylene glycol 185 g 1-Phenyl-3-pyrazolidone (phenidone) 22 g 5-Nitroindazole 0.4 g Starter Glacial acetic acid 120 g Potassium bromide 225 g Add water to make up to 1 liter (fixer solution formulation) Part-A (for finishing 18 liters) Ammonium thiosulfate (70 wt / vo) 1%) 6000 g sodium sulfite 110 g sodium acetate trihydrate 450 g sodium citrate 50 g gluconic acid 70 g 1- (N, N-dimethylamino) ethyl-5-mercaptotetrazole 18 g Part-B aluminum sulfate 800 g , Part A and Pa in about 5 liters of water
rtB was added at the same time, and water was added while stirring and dissolving.
Finished to 2 liters and adjusted pH to 10.40 with glacial acetic acid. This is used as a developer.

The starter was added to 1 liter of the developing solution at a rate of 20 ml / liter to adjust the pH to 10.26 to prepare a working solution.

The fixer was prepared by adding Par.
tA and PartB were added at the same time, water was added while stirring and dissolving to make up to 18 liters, and the pH was adjusted to 4.4 with sulfuric acid and sodium hydroxide. This is used as a fixing replenisher.

The processing temperature was 35 ° C. for development and 33 ° for fixing.
℃, water washing 20 ℃, drying 50 ℃, treatment time is dry to
The dry time is 45 seconds.

After the treatment, the sensitivity was measured. The sensitivity is represented by the reciprocal of the exposure amount that gives a density of fog + 0.5,
The relative sensitivity when the sensitivity under the storage condition A was 100. Table 1 shows the obtained results.

[0115]

[Table 1]

[0116]

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As is evident from Table 1, the sample according to the present invention provides high sensitivity with low fog regardless of the form of silver halide grains, and can be stored at high temperature and high humidity. (Storage condition B) The variation in sensitivity and fog is small and excellent.

[0118]

According to the present invention, it is possible to provide a silver halide light-sensitive material having improved sensitivity without fog and excellent storage stability.

Continued on the front page (72) Inventor Noriaki Kagawa 1 Konica Stock Company, Sakuracho, Hino-shi, Tokyo

Claims (1)

[Claims] 1. A silver halide photographic material having at least one light-sensitive silver halide emulsion layer on a support, wherein at least one of the silver halide emulsion layers is represented by the following general formula (I). A silver halide photographic material comprising silver halide grains sensitized by at least one compound selected from the group consisting of: Embedded image [In the formula, A represents a nitrogen-containing heterocyclic residue substituted with a mercapto group, a nitrogen-containing heterocyclic residue containing 4 to 5 nitrogen atoms as ring constituent atoms, a triazine ring residue or a benzotriazole ring residue, R ₁ , R ₂ and R ₃ each represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heterocyclic group. R ₂ and R ₃ may combine to form a heterocyclic ring. ]