JP2631995B2 - Silver halide photographic material - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a silver halide photographic light-sensitive material, and more particularly, to high sensitivity, excellent pressure resistance, and excellent rapid processing suitability in short-time exposure to high illuminance. And a silver halide photographic light-sensitive material.

[Conventional technology]

In recent years, the scanner system has been widely used in the printing plate-making field. There are various types of recording devices that use the scanner-type image forming method, and the recording light source of these scanner-type recording devices is a glow lamp, a xenon lamp, a tungsten lamp, an LED, or a He-Ne laser or an argon laser. There are semiconductor lasers and the like.

Various characteristics are required for the photosensitive material used in these scanners, but especially under such conditions, high sensitivity and high contrast can be obtained because of exposure with a short exposure time of 10 ^-3 to 10 ^-7 seconds. Is an essential condition. In the facsimile field in particular, it is important to have rapid processing aptitude for emphasis on quick reportability, and in the future, the number of lines will increase and the light beam will be narrowed down for faster scanning and higher image quality. Therefore, development of a photosensitive material having high sensitivity and high contrast has been strongly desired.

The development of silver halide grains having a core / shell structure has hitherto been carried out with the aim of increasing the sensitivity and improving the image quality by the effect of suppressing the development by iodine ions. These techniques are described, for example, in JP-A-59-188639, No. 59-177535, No. 59-1813
No. 37, No. 59-192,241, No. 60-11838, No. 60-138538
And No. 60-254032. However, silver halide emulsions having these core / shell structure grains have a high silver iodide content inside the grain material, so that sensitization is achieved, but the fixing speed is low, and the printing field is low. When applied to a photosensitive material that requires rapid processing, there is a disadvantage that a fixing failure occurs. As a result of repeated investigations by the present inventors, this fixing defect is related to the average silver iodide content, and the average silver iodide content is 2.5 mol%.
It has been found that a good fixing speed can be obtained by the following. On the other hand, to reduce the average silver iodide content to 2.5 mol% or less can be achieved by reducing the silver iodide content of the core or reducing the volume of the core relative to the shell. The silver halide grains having such a core / shell structure have a disadvantage in that the pressure resistance is deteriorated, and fogging is liable to occur particularly due to pressure.

Pressure is applied to the photosensitive material at the time of transportation and cutting during the manufacturing process. Further, in handling, it is inevitable that humans or mechanical pressures are applied during exposure and development.

When pressure is applied to the light-sensitive material in this manner, pressure is applied to the halide grains using gelatin, which is a binder for the silver halide grains, or a high-molecular substance as a medium. When pressure is applied to silver halide grains, blackening or desensitization not corresponding to the exposure amount may occur. For example, KBMather, J.Opt.soc.Am.,
38 , 1054 (1948) and P. Faelens, J. Phot. Sci., 2 , 105 (195
4) etc. As a means for improving the concentration change due to such pressure, a method of incorporating a plasticizer such as a polymer or an emulsion, a method of reducing silver halide / gelatinization in a silver halide emulsion layer or a light-sensitive material, and the like. It is known that the pressure is reduced before the pressure reaches the particles.

British Patent No. 738,618 discloses a heterocyclic compound.
No. 738,639, an alkyl ester, U.S. Pat.No. 2,960,404, a polyhydric alcohol, U.S. Pat.No. 3,121,060, a carboxyalkyl cellulose, and JP-A-49-5017, paraffin and carboxylic acid. JP-B-53-28086 discloses a method using an alkyl acrylate and an organic acid.

However, the method of adding a plasticizer reduces the mechanical strength of the emulsion layer, and thus its use amount is limited. When the silver halide / gelatin ratio is increased, the development progress is delayed, and rapid processing suitability is promoted. Has the disadvantage of

On the other hand, techniques for adding a polyhydroxybenzene compound to a light-sensitive material are described in JP-A-54-40629, JP-A-56-1936,
These are disclosed in JP-A-62-21143, JP-A-62-269137 and the like. Particularly, Japanese Patent Application Laid-Open No. Sho 62-21143 discloses that
It has been shown that the presence of polyhydroxybenzene at a concentration of less than × 10 ^-2 mol can reduce the increase in sensitivity due to pressure. However, this patent discloses a high contrast negative development system using aryl hydrazides,
Is a system using silver iodobromide grains containing silver iodide.

Furthermore, the sensitivity is insufficient, and the performance does not reach satisfactory.

[Object of the invention]

Accordingly, it is an object of the present invention to firstly provide a photosensitive material which is highly sensitive at the time of high illuminance exposure, and secondly to provide a photosensitive material which has an excellent rapid processing suitability with a high fixing speed and a high developing speed. A third object is to provide a photosensitive material that achieves the first and second objects and has excellent pressure resistance.

[Configuration of the invention]

The object of the present invention is to provide a silver halide photographic material having at least one silver halide emulsion layer on a support, wherein the silver halide emulsion has a silver iodide content in the shell smaller than that of the core. The core has a silver iodide content of 1 to 15 mol%, and the average silver iodide content of the whole grain is 2.5
mol%, and silver haloiodide grains having a substantially core / shell structure obtained by coexisting an iridium salt in the course of silver halide grain formation or physical ripening,
Further, the present invention has been attained by a silver halide photographic material characterized by having at least one kind of polyhydroxybenzenes.

(Specific Configuration of the Invention) The specific configuration of the present invention will be described in detail.

The core / shell silver halide grains according to the present invention include:
A core portion made of silver halide containing silver iodide and a shell portion made of silver halide having a silver iodide content lower than the core portion covering the core portion, and the shell portion has a thickness of
It is preferably from 0.01 to 0.3 μm, and more preferably from 0.05 to 0.2 μm. The silver iodide content of the core portion is 1 to 15
mol%, more preferably 3 to 12 mol%, and the silver iodide content of the shell part is preferably 0 to 2 mol%, more preferably 0 to 1 mol%. The silver halide composition is preferably mainly silver iodobromide, but may contain silver chloride as long as the effects of the present invention are not impaired. The average silver iodide content of the total silver halide grains is less than 2.5 mol%, and more preferably 0 to 2 mol%. The particle having “substantially a core / shell structure” in the present invention means that the core portion may have a layered structure of two or more layers. When the core portion has a layered structure of two or more layers, at least one of the layers is made of silver haloiodide having a higher silver iodide content than the shell (outermost layer).

Preferably, the average silver iodide content in the core portion is larger than the silver iodide content in the shell portion.

The difference between the silver iodide content of the core part and the shell part is preferably 3 mol% or more, particularly preferably 3 to 5 mol%.

As for the ratio (molar ratio) of the silver amount between the core portion and the shell portion, the shell is preferably 1 to 9, particularly preferably 3 to 5, with respect to the core 1.

The shape of the silver halide grains according to the present invention may be, for example, any of a cubic octahedron, a tetradecahedron, a plate-like body, and a spherical body, but a monodisperse grain composed of a cube and a tetradecahedron is preferred.

The monodisperse grains as used herein mean a silver halide emulsion having a grain size distribution having a coefficient of variation defined below of 20% or less, particularly preferably 15% or less.

Where the coefficient of variation is Is defined as

The photographic emulsion used in the present invention is Chimie by P. Glafkides.
et Physlque Photographique (published by Paul Montel, 1967
Photographic Emulsion Chemistry by GFDuffin
(The Focal Press, 1966), VLZelikman et al
By Making and Coating Phoographic Emulsion (The Foc
al Press, 1964) and the like.

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 with a soluble halide may be any one of a one-sided mixing method, a double-sided mixing method, and a combination thereof. Good.

A method of forming grains in the presence of excess silver ions (a so-called reverse mixing method) can also be used. PA in the liquid phase where silver halide is formed as a form of the double jet method.
The method of keeping g constant, that is, the so-called controlled
The double jet method can also be used.

According to this method, a silver halide emulsion having a regular crystal form and a nearly uniform grain size can be obtained.

In order to make the particle size uniform, British Patent 1,
No. 535,016, JP-B-48-36890 and JP-B-52-16364, a method in which the addition rate of silver nitrate or alkali halide is changed according to the grain growth rate,
It is preferable to use a method of changing the concentration of an aqueous solution as described in JP-A-Sho 4,242,445 and JP-A-55-158124 to grow the solution quickly within a range not exceeding the critical saturation.

In the case of tabular grains, JP-B-47-11,386,
It is preferable to use particles having a uniform particle size and / or thickness as described in Japanese Patent Application Nos. 61-48950 and 61-299155.

In addition, a known method can be used for the production of the core / shell type emulsion. For example, Japanese Patent Publication No. 49-21657,
JP-A-51-39027, JP-A-54-118823, JP-A-58-108528
No. 59-29243, No. 59-52237, No. 59-74548,
The description of JP-A-59-116645 and JP-A-59-149344 can be referred to.

In the present invention, the coexistence of an iridium salt (including its complex salt) in the process of silver halide grain formation or physical ripening has a remarkable effect on sensitization, high contrast, and improvement in development progress. The preferred range is 1 × 10 ^-8 to 1
× 10 ⁻⁶ / silver mol. In the present invention, it can be added to either or both of the core and the shell.

As the silver halide solvent used in the present invention, U.S. Patent Nos. 3,271,157, 3,531,289, and 3,574,628
(A) organic thioethers described in
(B) Thiourea derivatives described in JP-A-82408 and JP-A-55-77737; (c) Silver halide solvent having an oxygen or carbonyl group described in JP-A-53-144319;
D) imidazoles (e) sulfites (f) thiocyanates described in JP-100717. Of these, thioethers are particularly preferred. The specific compounds are shown below.

_{HO- (CH 2) 2 -S- (} CH 2) 2 -S- (CH 2) a silver halide emulsion to be used in ₂ -OH present invention is usually chemically sensitized. As the method of chemical sensitization, known methods such as a sulfur sensitization method, a reduction sensitization method, and a noble metal sensitization method can be used, and they can be used alone or in combination.

Among the noble metal sensitization methods, the gold sensitization method is a typical one and uses a gold compound, mainly a gold complex salt. Noble metals other than gold, for example, complex salts such as platinum, palladium and iridium may be contained.

As the sulfur sensitizer, various sulfur compounds such as thiosulfates, thioureas, thiazoles, rhodanines and the like can be used in addition to the sulfur compounds contained in gelatin.

Stannous salts, amines, formamidinesulfinic acid, silane compounds and the like can be used as the reduction sensitizer.

The polyhydroxybenzene compound of the present invention is preferably a compound having any one of the following structures.

X and Y are each -H, -OH, halogen atom -OM (M
Is an alkali metal ion), -alkyl group, phenyl group,
Amino group, carbonyl group, sulfone group, sulfonated phenyl group, sulfonated alkyl group, sulfonated amino group,
A sulfonated carbonyl group, a carboxyphenyl group, a carboxyalkyl group, a carboxyamino group, a hydroxyphenyl group, a hydroxyalkyl group, an alkyl ether group, an alkylphenyl group, an alkylthioether group, or a phenylthioether group.

More preferably, -H, -OH, -Cl, -Br, -COO
_{H, -CH 2 CH 2 COOH,} -CH 3, -CH 2 CH 3, -CH (CH 3) 2,
_{-C (CH 3) 3, -OCH} 3, -CHO, -SO 3 Na, -SO 3 H, -S
CH ₃ , And so on. X and Y may be the same or different.

Particularly preferred representative compound examples are The substituents X and Y and the compound of the present invention are not limited to the above.

The polyhydroxybenzene compound of the present invention may be added to an emulsion layer in the light-sensitive material or may be added to a layer other than the emulsion layer. The addition amount is effective in the range of 10 ^-5 to 1 mol per 1 mol, and is particularly effective in the range of 10 ^-3 to 10 ^-1 mol.

The photosensitive silver halide emulsion of the present invention may be spectrally sensitized to a relatively long wavelength blue light, green light, red light or infrared light by a sensitizing dye. As sensitizing dyes, cyanine dyes, merocyanine dyes, complex cyanine dyes,
Complex merocyanine dyes, holo-holer cyanine dyes, styryl dyes, hemicyanine dyes, oxonol dyes, hemioxonol dyes and the like can be used.

Useful sensitizing dyes for use in the present invention are, for example, RESEARCH
DISCLOSURE Item17643 Section IV-A (P.23, December 1978),
It is described in the literature described or cited in Item 1831, Section X (P.437, August 1979).

In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various scanner light sources can be advantageously selected.

For example, B) For helium-neon laser light sources, see JP-A-50-62425, JP-A-54-18726, and JP-A-59-102229.
No. 48-42172, 51-9609 and 55-39818, which are described in Japanese Patent Application Laid-Open No. Sho 62-284343. Cyanines. D) Japanese Patent Application Laid-Open No. 59-19 / 1989
No. 1032, JP-A-60-80841, and tricarborocyanines described in JP-A-59-192242, and dicarbocyanines containing a 4-quinoline nucleus described in JP-A-59-192242 are advantageously selected.

 The representative compounds of these sensitizing dyes are shown below.

Specific compound of B) Specific compound of C) General formula [I] Wherein Y ₁ and Y ₂ each represent a non-metallic atomic group necessary to form a heterocyclic ring such as a benzothiazole ring, a benzoselenazole ring, a naphthothiazole ring, a naphthoselenazole ring, or a quinoline ring; These heterocycles may be substituted with a lower alkyl group, an alkoxy group, a hydroxy group, an aryl group, an alkoxycarbonyl group, or a halogen atom.

R ₁ and R ₂ each represent a lower alkyl group, a sulfo group or an alkyl group having a carboxy group.

R ₃ represents a lower alkyl group. X ₁ represents an anion.

_n1 and _n2 represent 1 or 2.

_m represents 1 or 0, and in the case of an inner salt, _m = 0. 〕 In particular Specific compound of D) In particular, the combination with the sensitizing dye of the above C) is preferable because the sensitivity can be increased.

These sensitizing dyes may be used alone or in combination, and a combination of sensitizing dyes is often used particularly for supersensitization. Along with sensitizing dye,
A dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and which exhibits supersensitization may be contained in the emulsion.

Useful sensitizing dyes, combinations of dyes exhibiting supersensitization, and substances exhibiting supersensitization are described in Research Disclosure (Rese
arch Disclosure) Volume 176 17643 (Issued December 1978) No. 23
It is described in section J on page IV.

The light-sensitive material of the present invention may contain various compounds for the purpose of preventing fogging during the manufacturing process, storage or photographic processing of the light-sensitive material or stabilizing photographic performance. That is, azoles such as benzothiazolium salts, nitroindazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptothiadiazoles, aminotriazoles, benzothiazoles, nitrobenzotriazoles, Mercaptopyrimidines; mercaptotriazines; thioketo compounds such as oxazolinethione; azaindenes such as triazaindenes, tetraazaindenes (especially 4-hydroxy-substituted (1,3,3a, 7) tetrazaindene) ), Pentaazaindenes; and many other compounds known as antifoggants or stabilizers, such as benzenethiosulfonate, benzenesulfonate, benzenesulfonamide, and the like. Rukoto can.

The photosensitive material prepared by using the present invention may contain a water-soluble dye in the hydrophilic colloid layer as a filter dye or for various purposes such as prevention of irradiation. Such dyes include thixonol dyes, hemioxanol dyes, styryl dyes, merocyanine dyes, cyanine dyes and azo dyes. Among them, oxonol dyes; hemioxonol dyes and merocyanine dyes are useful.

In the photographic emulsion layer of the photographic light-sensitive material of the present invention, for example, polyalkylene oxide or an ether, ester thereof,
A developing agent such as a derivative such as an amine, a thioether compound, a thiomorpholin, a quaternary ammonium salt compound, a urethane derivative, a urea derivative, an imidazole derivative, a 3-pyrazolidone or an aminophenol may be contained.

Among them, 3-pyrazolidones (1-phenyl-3-pyrazolidone, 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone, etc.) are preferable, and usually 5 g.
/ m ² or less, and more preferably 0.01 to 0.2 g / m ² .

The photographic emulsion and the non-photosensitive hydrophilic colloid of the present invention may contain an inorganic or organic hardener. For example, active vinyl compounds (1,3,5-triacryloyl-hexahydro-s-triazine, bis (vinylsulfonyl) methyl ether, N, N-methylenebis- [β- (vinylsulfonyl) propionamide], etc.), active halogen compounds (E.g., 2,4-dichloro-6-hydroxy-s-triazine), mucohalic acids (e.g., mucochloric acid), N-carbamoylpyridium salts (e.g., ((1-morpholy) carbonyl-3-pyridinio) methanesulfonate), Haloamidinium salts (such as 1- (1-chloro-1-pyridinomethylene) pyrrolidinium and 2-naphthalene sulfonate) can be used alone or in combination. Among them, JP-A-53-41220, JP-A-53-57257, JP-A-59-162546,
Active vinyl compounds and U.S. Pat.
The active halides described in 3,325,287 are preferred.

The photographic emulsion layer or other hydrophilic colloid layer of the light-sensitive material prepared by using the present invention may have coating aids, antistatic, slipperiness improvement, emulsification / dispersion, adhesion prevention and photographic property improvement (eg, development acceleration, high contrast For various purposes such as sensitization), various surfactants may be contained.

For example, saponins (steroids), alkylene oxide derivatives (eg, polyethylene glycol, polyethylene glycol / polypropylene glycol condensate, polyethylene glycol alkyl ethers or polyethylene glycol alkyl aryl ethers, polyethylene glycol esters, polyethylene glycol sorbitan esters, polyalkylene glycol) Nonionic interfaces such as alkylamines or amides, polyethylene oxide adducts of silicone, glycidol derivatives (eg, alkenyl succinic acid polyglyceride, alkylphenol polyglyceride), fatty acid esters of polyhydric alcohols, and alkyl esters of sugars. Activator; alkyl carboxylate, alkyl sulfonate, alkyl benzene sulfo Acid salts, alkyl naphthalene sulfonates, alkyl sulfates, alkyl phosphates, N-acyl-N-alkyltaurines, sulfosuccinates, sulfoalkylpolyoxyethylene alkylphenyl ethers, polyoxyethylene Anionic surfactants containing an acidic group such as a carboxy group, a sulfo group, a phospho group, a sulfate group, or a phosphate group, such as alkyl phosphates; amino acids, aminoalkyl sulfonic acids, aminoalkyl sulfate or Amphoteric surfactants such as phosphoric esters, alkylbetainic acids, and amine oxides; alkylamine salts,
Cationic surfactants such as aliphatic or aromatic quaternary ammonium salts, heterocyclic quaternary ammonium salts such as pyridinium and imidazolium, and phosphonium or sulfonium salts containing aliphatic or heterocyclic rings can be used.

It is preferable to use a fluorinated surfactant described in JP-A-60-80849 or the like for antistatic.

The photographic light-sensitive material of the present invention may contain a matting agent such as silica, magnesium oxide, or polymethyl methacrylate for the purpose of preventing adhesion to a photographic emulsion layer or other hydrophilic colloid layers.

The light-sensitive material used in the present invention may contain a dispersion of a water-insoluble or hardly soluble synthetic polymer for the purpose of dimensional stability. For example, use is made of a polymer having, as a monomer component, an alkyl (meth) acrylate, an alkoxyacryl (meth) acrylate, a glycidyl (meth) acrylate, or the like alone or in combination, or a combination thereof with acrylic acid, methacrylic acid, or the like. be able to.

Gelatin is advantageously used as a condensing agent or protective colloid of the photographic emulsion, but other hydrophilic colloids can also be used. For example, gelatin derivatives,
Graft polymers of gelatin with other polymers, proteins such as albumin and casein; cellulose derivatives such as hydroxyethylcellulose, carboxymethylcellulose and cellulose sulfates; sodium alginate;
Sugar derivatives such as starch derivatives, polyvinyl alcohol, polyvinyl alcohol partial acetal, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, and various kinds of copolymers such as polyvinylpyrazole. Synthetic hydrophilic polymeric substances can be used.

As gelatin, coal-treated gelatin, acid-treated gelatin may be used, and gelatin hydrolyzate and gelatin enzyme hydrolyzate can also be used.

The silver halide emulsion layer used in the present invention may contain a polymer latex such as an alkyl acrylate.

As a support of the light-sensitive material of the present invention, cellulose triacetate, cellulose diacetate, nitrocellulose, polystyrene, polyethylene terephthalate paper, baryta-coated paper, polyolefin-coated paper and the like can be used.

For the photographic processing of the light-sensitive material of the present invention, any of known methods can be used. Known treatment liquids can be used. The processing temperature is usually selected between 18 ° C and 50 ° C, but may be lower than 18 ° C or higher than 50 ° C.

The developer used for black-and-white photographic processing can contain a known developing agent. As a developing agent, dihydroxybenzenes (for example, hydroquinone), 3
-Pyrazolidones (for example, 1-phenyl-3-pyrazolidone), aminophenols (for example, N-methyl-
p-aminophenol), 1-phenyl-3-pyrazolines, ascorbic acid, and a heterocyclic compound in which a 1,2,3,4-tetrahydroquinoline ring and an indole ring described in U.S. Pat. No. 4,067,872 are condensed Can be used alone or in combination. The developer generally contains other known preservatives, alkali agents, pH buffers, antifoggants and the like, and further, if necessary, dissolution aids, color tones, development accelerators, surfactants, antisaturants, Water softener, hardener,
A viscosity imparting agent or the like may be included.

As the fixing solution, those having a commonly used composition can be used.

As fixing agents, in addition to thiosulfate and thiocyanate,
An organic sulfur compound known to have an effect as a fixing agent can be used.

The fixer may contain a water-soluble aluminum salt as a hardener.

The light-sensitive material of the present invention is preferably processed using an automatic developing machine, which enables rapid processing and the like. At this time, the developing step is 30 to 45 ° C for 5 to 60 seconds, the fixing step is 30 to 45 ° C for 5 to 30 seconds, and the washing step is 30 to 45 ° C.
It is preferable to carry out under conditions of 5 ° C. and 5 to 30 seconds. In this case, it is preferable to use an acidic hardening fixing bath containing a polyvalent metal as the fixing bath.

〔Example〕

Hereinafter, the present invention will be described specifically with reference to Examples.
The present invention is not limited by these.

Example 1 Preparation of Emulsion A Group (Emulsion A-1): A mixed aqueous solution of potassium iodide and potassium bromide and an aqueous silver nitrate solution were vigorously stirred in a gelatin aqueous solution containing 1,8-dihydroxy-3,6-dithiaoctane. The mixture was added at 75 ° C. for 15 minutes while controlling the pAg to be 8.0 to obtain monodispersed octahedral silver iodobromide having an average particle size of 0.25 μm and an iodine content of 6 mol%.

Using this silver iodobromide emulsion as a core, 10 ^-7 per mol of Ag
A core / shell silver iodobromide emulsion was obtained by adding an aqueous solution of potassium bromide and an aqueous solution of silver nitrate containing moles of K ₃ IrCl ₆ so that pAg = 7.4.

After desalting this emulsion according to the simplex method, 3 mg per mole of silver
Of sodium thiosulfate and 4 mg of chloroauric acid
Chemical sensitization was performed at 5 ° C. for 70 minutes. As a stabilizer, 30 ml of a 1% solution of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene was added per mole of silver.

Finally, a 0.45 μm monodispersed cubic emulsion having an average silver iodide content of 1.5 mol% was obtained. (Coefficient of variation 10%) (Preparation of Emulsions A-2 to A-7) The preparation method was the same as that for Emulsion A-1, except that the iodine content of the core particles and the iodine content of the shell were changed. Emulsions A-2 to A-8 having the following formulas were prepared.

At that time, the addition amount of 1,8-dihydroxy-3,6-dithiaoftan was adjusted so that the final particle size was 0.45.

Preparation of Coated Samples The above emulsion was treated with 3,3'-di (3-
Sulfopropyl) -5,5'-dichloro-9ethyl-naphtho [1,2-d] thiacarbocyanine sodium salt and 3,3 '
-Di (3-sulfopropyl) -9ethyl-naphtho [1,2
-D] 50 mg each of thiacarbocyanine sodium salt and 1 mol of silver halide were added, and the compound of A-1 was added as shown in Table 1. Further, 1-phenyl-5-mercaptotetrazole is used as an antifoggant in a mole of silver.
50mg, polyethyl acrylate latex gelatin binder ratio of 25% as a plasticizer, a 2-bis (vinylsulfonyl acetamide) ethane as a hardening agent 120 mg / m ² In addition, like the silver in silver 4.5 g / m ² on a polyester support Was applied. Gelatin was 4.7 g / m ² .

As a protective layer thereon, gelatin 1.5 g / m ^{2 as a} matting agent, polymethyl methacrylate 60 mg / m ² having a particle size of 3 to 4 μm,
(As a colloidal Le silica 70 mg / m ² coating aid particle size 10～20Emumyu, dodecylbenzenesulfonic Huong acid silicone oil
Samples Nos. 1 to 16 were prepared by simultaneously applying layers containing sodium salt and a surfactant having the following structural formula (100 mg / m ² added).

Evaluation of Sensitivity The obtained sample was exposed to xenon flash light having an emission time of ^{10-5 "} through an interference filter having a peak at 670 nm and a continuous azalea.

After developing at 35 ° C. and 30 ″ using developing solution A, using fixing solution B
It was fixed at 25 ° C. and 60 ″, washed with water and dried, and subjected to sensitometry.

The reciprocal of the exposure amount giving a density of 3.0 was defined as the sensitivity, and the relative sensitivity is shown in Table 1.

Evaluation of pressure resistance A 40 g load was placed on a 0.1φ sapphire needle, and the sample surface was 60 cm /
He slid in minutes and put pressure on his trial. The sample was developed, fixed, washed with water and dried under the same conditions as above without exposure. The density of the pressure portion was measured by a microdensitometer having an aperture of 50 μm, and the difference in density from the portion where no pressure was applied was shown in Table 1 as ΔD.

Evaluation of Fixing Property After the unexposed sample was developed under the same conditions as above, fixing was performed using Fixing Solution B under two conditions of 25 ° C. 25 ″ and 25 ° C. 15 ″, followed by washing and drying. When the sample was completely fixed (visual observation), it was evaluated as ○, and even when a small portion of the unfixed portion remained, the result was shown in Table 1 as x.

Developer A Water 720 ml Ethylenediaminetetraacetic acid disodium salt 4 g Sodium hydroxide 44 g Sodium sulfite 45 g Sodium carbonate 26.4 g Boric acid 1.6 g Potassium bromide 1 g Hydroquinone 36 g Diethylene glycol 39 g 5-Methyl-benzetriazole 0.2 g Pyrazone 0.7 g Add water 1 Fixer B Ammonium thiosulfate 170 g Sodium sulfite (anhydrous) 15 g Boric acid 7 g Glacial acetic acid 15 ml Potassium alum 20 g Ethylenediaminetetraacetic acid 0.1 g Tartaric acid 3.5 g Add water and add 1 invention It is understood that the samples 1, 2, 4, and 5, which are embodiments of the above, have good performance in all respects of sensitivity pressure resistance and fixability.

Example 2 Monodisperse cubes as in Emulsion A, but with the addition of 1,8-dihydroxy-3,6-dithiaoctane being adjusted to a final 0.3 μm halogen composition of Table 2 having a core of 0.16 μm. Core / shell silver iodobromide emulsions B-1 to B-8 were obtained.

Table 2 shows the results of application and evaluation in the same manner as in Example 1.

Samples 17, 18, 20, and 21, which are embodiments of the present invention, showed good performance even when the particle size was as small as 0.3 μm.

Example 3 Emulsion A-1 was used, except that the compounds shown in Table 3 were added in place of compound A-1 in an amount of 3 × 10 ^-2 mol per mol of silver. Table 3 shows the results of the evaluation.

Also in this case, the samples 34 to 43 according to the embodiment of the present invention showed good performance.

Example 4 Emulsions C-1 to C3 were prepared in the same manner as in Emulsion A except that the pAg for shell formation was controlled at 8.5. Finally, the particles were 0.5 μm monodisperse octahedral particles. Table 4 shows the results of coating and evaluation in the same manner as in Example 1.

Although the sensitivity was inferior to that of Example 1, the effect of the present invention was also recognized in the case of octahedral particles.

Preferred embodiments of the present invention are as follows.

1) The light-sensitive material according to claim 1, wherein the coefficient of variation of silver halide grains having a core / shell structure is 15% or less.

2) Difference in silver iodide content between core and shell is 3 to 15 mol%
The light-sensitive material according to claim 1, wherein:

3) The light-sensitive material according to claim 1, wherein the iridium salt is contained in the halogenated particles.

4) The light-sensitive material according to claim, wherein the silver halide emulsion is spectrally sensitized with a sensitizing dye represented by the formula (I) described in the text.

5) The light-sensitive material according to claim 1, wherein the silver halide emulsion is spectrally sensitized with a trinuclear cyanine dye.

6) The light-sensitive material according to claim 1, wherein the silver halide emulsion is cubic or tetradecahedral monodispersed grains.

Claims (1)

(57) [Claims] 1. A silver halide photographic material having at least one silver halide emulsion layer on a support, wherein the silver halide emulsion has a smaller silver iodide content in the shell than in the core. And the silver iodide content of the core is 1 to 15 mol
%, The average silver iodide content of the whole grain is less than 2.5 mol%, and the substantially core / shell structure obtained by coexisting an iridium salt in the course of silver halide grain formation or physical ripening is used. A silver halide photographic light-sensitive material comprising silver halide grains having at least one kind of polyhydroxybenzenes.