JPH0764223A - Silver halide photographic sensitive material - Google Patents

Abstract

PURPOSE:To eliminate fog due to safelight and to obtain a silver image pure in black tone by using flat silver halide grains having 2 crystal faces (100) parallel to each other as principal faces and having dislocation lines. CONSTITUTION:The silver halide photographic sensitive material has at least one silver halide emulsion layer on at least one side of a support and the silver halide grains in this emulsion layer have 2 crystal faces (100) parallel to each other as the principal faces and the dislocation lines, and these silver halide grains may have crystal faces, such as faces (111) and (110), in addition to the principal faces (100), and their composition may be any of silver chloride, silver bromide, silver iodide, silver chlorobromide, or silver iodobromide, but it is preferred to be silver iodobromide from the viewpoint of high sensitivity.

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 light-sensitive material which has high sensitivity and suppresses the occurrence of safelight fog and has a good silver tone.

[0002]

BACKGROUND OF THE INVENTION Parallel to US Pat. No. 4,063,951
A method for producing a silver halide emulsion comprising tabular grains having an aspect ratio of 1.5 to 7 with one (100) plane as a main plane is disclosed. Further parallel to US Pat. No. 4,386,156 is 2
A silver halide emulsion comprising tabular grains of silver bromide having one (100) plane as a main plane and an aspect ratio of 8 or more, and a production method are disclosed. It has been shown that these techniques are effective in increasing the contrast and increasing the maximum density in comparison with an emulsion composed of silver halide grains composed of (100) faces such as cubes. However, when these emulsions are used, the color tone of the silver image is clear and becomes not a pure black tone but a yellowish black color. Furthermore, by adding a sensitizing dye for color sensitization. It was further deteriorated by color contamination due to the residual color after the treatment. For example, when it is used in a medical silver halide photographic light-sensitive material for directly observing a silver image, it gives an unpleasant impression to an observer and a diagnostician of a lesion.

Further, it has been found that there is a drawback that fog is likely to occur due to a safe light of red light used in dark room work. On the other hand, regarding the dislocation of silver halide crystal grains, CRBerry; J.App.Ph
ys., 27 , 636, (1956), JH Hamilton, Photo.Sci. Eng., 1
1, 57 (1967), Shiozawa; Nissha, 35 , 213, (1972). In these documents, it is possible to observe dislocations in the crystal by X-ray diffractometry or low-temperature transmission electron microscopy, and various dislocations are generated in the crystal by intentionally straining the crystal. Things etc. are described.

Dislocations, like crystal defects, are one of the imperfections in the crystal structure and are known to have an important effect on the grain growth process and chemical sensitization process. Dislocations include edge dislocations and screw dislocations.
However, it is said that the position where the dislocation line intersects with the crystal grain surface is highly reactive and is likely to generate a chemical sensitized nucleus along with the kink position.

For example, JP-A-63-220238 and JP-A-1-20164
No. 9, JP-A No. 4-372943 and the like, dislocations are intentionally introduced,
Techniques have been disclosed that seek to improve various photographic properties.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a high-sensitivity image, a fog due to safelight does not occur when the film is handled in a dark room, and the formed silver image has a pure black tone. The object is to provide a silver halide photographic light-sensitive material.

[0007]

The above object of the present invention is to provide a silver halide photographic light-sensitive material having at least one silver halide emulsion layer on at least one side of a support. It was achieved by a silver halide photographic light-sensitive material characterized in that the silver halide grain is a tabular silver halide grain having two (100) planes parallel to each other as main planes and having dislocation lines.

According to the present invention, not only the effect of improving the silver tone but also the suppression of safe light fog was a surprising effect.

The present invention will be described in more detail below.

The average grain size of the tabular silver halide grains according to the present invention is preferably 0.3 to 3.0 μm, particularly preferably 0.5 to 3.0 μm.
~ 1.5 μm. In the present invention, the average grain size of tabular silver halide grains means the average length of major plane sides of the grains.

The tabular silver halide grain of the present invention has an average value of side length / thickness (called aspect ratio) of grain (called average aspect ratio) of 2.0 or more, preferably
2.0 to 20.0, particularly preferably 2.2 to 8.0. To obtain the average aspect ratio, measure at least 100 samples.

The average thickness of the tabular silver halide grains of the present invention is preferably 0.5 μm or less, particularly preferably 0.3 μm or less.

The advantage of such tabular grains is that, for example, spectral sensitization efficiency can be improved, image graininess and sharpness can be improved. For example, British Patent 2,112,157 and US Pat.
No. 20, No. 4,433,048, No. 4,414,310, No. 4,434,226 and the like. In the present invention, the length of the side of the main plane of the tabular silver halide grain is defined as the length of the side of a square having an area equal to the projected area of the grain from the observation of an electron micrograph of the silver halide emulsion grain. It

The tabular silver halide grains of the present invention are (10
It has a main plane consisting of 0) plane.

In the present invention, the thickness of a silver halide grain means the minimum distance between two parallel (100) planes having the largest area and forming a tabular silver halide grain (that is, between the principal planes). Distance).

The thickness of the tabular silver halide grains can be determined from an electron micrograph of a shaded silver halide grain or an electron micrograph of a sample slice obtained by coating a silver halide emulsion on a support and drying. .

In the silver halide emulsion of the present invention, the tabular silver halide grains of the present invention account for 50% or more, preferably 60% or more, and particularly preferably 70% of the total projected area. That is all.

The tabular silver halide grains of the present invention may have crystal planes other than the (100) plane of the main plane, such as (111) plane and (110) plane. The tabular silver halide emulsion of the present invention is preferably monodisperse, and those having a coefficient of variation of grain size within 20% are particularly preferably used, but monodisperse grains having different average grain sizes are used. Tabular silver halide emulsions or polydisperse emulsions having a wide grain size distribution may be mixed within a range that does not impair the effects of the present invention.

The coefficient of variation referred to in the present invention is the particle size (the length of the side of a square having an area equal to the main plane area of each particle).
The difference (standard deviation) is divided by the average particle size and multiplied by 100.

The tabular silver halide emulsion according to the present invention comprises
Although the halogen composition such as silver chloride, silver bromide, silver iodide, silver chlorobromide, and silver iodobromide is arbitrary, silver iodobromide is preferable from the viewpoint of high sensitivity, and the average silver iodide content is 5.0. It is at most mol%, particularly preferably at most 3.0 mol%.

The tabular silver halide grains of the present invention are
It may have a plane defect such as a twin plane inside, may have a uniform halogen composition within the grain, and may be a core / shell type grain having a localized portion of silver iodide inside.

Regarding the method for producing the tabular silver halide emulsion, US Pat. Nos. 4,063,951 and 4,386,156 can be referred to.

The size and shape of tabular silver halide grains can be controlled by the temperature during grain formation, pH, pH, addition rate of silver salt and halide aqueous solution, and the like.

When forming the tabular silver halide grains of the present invention,
The pAg is preferably 5.0 to 8.0.

The average silver iodide content of the tabular silver halide emulsion can be controlled by changing the composition of the aqueous halide solution to be added, that is, the ratio of chloride, bromide and iodide.

When the tabular silver halide emulsion is produced,
If necessary, a silver halide solvent such as ammonia, thioether or thiourea can be used.

The above-mentioned emulsion is either a surface latent image type that forms a latent image on the grain surface, an internal latent image type that forms a latent image inside the grain, or a type that forms a latent image on the surface and inside. You may. These emulsions may be prepared by using an iron salt, a cadmium salt, a lead salt, a zinc salt, a thallium salt, a ruthenium salt, an osmium salt, an iridium salt or a complex salt thereof, a rhodium salt or a complex salt thereof at the stage of physical ripening or grain preparation. Good.

The emulsion may be subjected to a water washing method such as a Nudell water washing method or a flocculation sedimentation method in order to remove soluble salts. A preferred washing method is, for example, Japanese Patent Publication Sho
Particularly preferable desalting method is a method using an aromatic hydrocarbon aldehyde resin containing a sulfo group described in JP-A-35-16086 or a method using G3, G8, etc., as an aggregation polymer agent described in JP-A-63-158644. Can be mentioned.

The silver halide emulsion of the present invention has dislocations. The dislocations of silver halide grains are described, for example, in JH Hamil above.
ton, Photo. Sci. Eng., 11,57 (1967) and Shiozawa; Nisshi, 3
It can be observed by a direct method using a transmission electron microscope at a low temperature described in 5 , 213, (1972). That is, the silver halide grains that were taken out carefully so as not to apply pressure enough to cause transition from the emulsion to the grains were placed on the mesh of an electron microscope, and the sample was cooled so as to prevent damage (printout, etc.) due to electron beams. The state is observed by the transmission method. In this case, the thicker the silver halide grains,
Since it becomes difficult for the electron beam to pass through, it is possible to observe more clearly by using a high-pressure type (400 kv or more for 0.5 μm-thick particles) electron microscope. From the photographs of silver halide grains obtained by such a method, the number of dislocation lines can be counted for each grain. Number of dislocation lines is 1
The number of particles is 1 or more per particle, preferably 5 particles or more on average. More preferably, the average number is 10 or more per particle. When the dislocation lines are densely present, or when the dislocation lines intersect each other, the number of dislocation lines per grain may not be clearly counted. However, even in these cases, approximately 10, 20, 30
It can be counted as a book, and obviously,
This can be distinguished from the case where there are only a few. The average number of dislocation lines per grain is calculated as the number average by counting the number of dislocation lines for 100 grains or more.

Introduction of dislocation lines into grains is described, for example, in JP-A-63-2.
The method disclosed in No. 20238 can be used, and a dislocation line can be introduced at an arbitrary position and place in a silver halide grain. The preferred dislocation introduction position is
It is the time when 30 to 90%, and more preferably 50 to 95% of the amount of silver used is consumed. Examples of the dislocation-introducing place include, for example, the main surface of the grain, the vicinity of the apex, and the twin plane in the case of a grain having a ridge and a twin plane, but they may be limited to these positions, or they may be combined. May be.

The silver halide emulsion of the present invention is preferably chemically sensitized, but it is preferable to use chalcogen sensitization and gold sensitization together as the chemical sensitization method. Particularly, the combined use of gold sensitization and sulfur sensitization is preferable because not only the sensitizing effect is remarkable but also the fog suppressing effect is obtained.

For sulfur sensitization, examples of sensitizers include thiosulfate, allylthiocarbamidothiourea, allylisothiacyanate, cystine, p-toluenethiosulfonate, and rhodanine. Other U.S. Patents 1,574,944
No. 3,656,955, German Patent 1,422,869, Japanese Patent Sho 56
The sulfur sensitizers described in JP-A-24937 and JP-A-55-45016 can also be used. The sulfur sensitizer may be added in an amount sufficient to effectively increase the sensitivity of the emulsion. This amount can be varied over a wide range under various conditions such as pH, temperature and size of silver halide grains, but as a guide, it is preferably 10 ^-7 to 10 ^-1 mol per mol of silver halide.

For gold sensitization, gold sensitizers such as chloroauric acid salt, gold thiourea complex salt, potassium chloroaurate, auric trichloride, potassium auric thiocyanate, potassium iodoaurate, tetracyanoauric amide and ammonium auro are used. Examples thereof include thiocyanate and pyridyl trichlorogold. The addition amount of these gold sensitizers can be varied over a wide range under various conditions, but as a guide, it is 5 × 10 ^{-7 to} 5 per mol of silver halide.
It is preferably ^{x10 -3} mol, more preferably 2x10 ^-6 to 4x10 ^-4 mol.

In the present invention, reduction sensitization and hydrogen sensitization methods can be used. Stannous salt as a reduction sensitizer,
Amines, formamine disulfinic acid, silane compounds, borane compounds, ascorbic acid and its derivatives can be used.

The amount of the reduction sensitizer added varies depending on the reducibility of the compound and the emulsion production conditions such as the type of silver halide and the dissolution conditions, but it is 1 × 10 ^-8 to 1 × per mol of silver halide.
A range of 10 ^-2 mol is suitable.

The chemical ripening temperature of the emulsion according to the present invention is arbitrarily determined, but is preferably in the range of 20 to 90 ° C, preferably 30 to 80 ° C, and more preferably 35 to 70 ° C.

In the present invention, before the completion of the chemical sensitization step of the silver halide emulsion of the present invention (hereinafter, parent grain emulsion),
It is preferable to add a silver halide fine grain emulsion having a solubility product smaller than that of the parent grain emulsion.

A solubility product smaller than that of the parent grain emulsion means that
When the solubility product is represented by K _SP , K _SP = [Ag ⁺ ] · [X ⁻ ] where [Ag ⁺ ] represents the silver ion concentration and [X ⁻ ] represents the halogen ion concentration. Therefore, when the parent grain is silver chloride, the fine grain silver halide is silver bromide or silver iodide.

Of course, a mixed crystal of these halogen ions may be used as long as the value of K _SP is smaller in the fine silver halide grains than in the parent grains.

The types of silver halide fine grains according to the present invention include AgBr, AgI, AgClBr and AgBr.
There are I, AgClI and AgClBrI, but silver halide fine grains having substantially no photosensitivity are preferable.

The grain size of the above silver halide fine grains is preferably 0.1 μm or less, more preferably 0.07 μm or less, and particularly preferably 0.05 μm or less. As the silver halide fine particles, silver iodide fine particles are preferably used.

With respect to silver iodide, generally cubic γ-
AgI and hexagonal β-AgI are known, but the silver iodide fine particles may have any crystal structure,
Also, a mixture of these may be used.

Further, silver bromide as silver halide fine particles,
When a solid solution mainly composed of silver chloride or these rock salt structures is used, for example, when fine particles such as AgBr ₉₀ I ₁₀ are used, these fine particles have substantially no twin plane, that is, a so-called twin-free crystal. A normal crystal or a single twin crystal having one twin plane is preferable. Further, the fine silver halide grains preferably have good monodispersibility, and are preferably prepared by the double jet method while controlling the temperature, pH and pAg.

The addition amount of fine silver halide grains is preferably 1/100 dmol or less per 1 mol of the parent grain emulsion, and more preferably 1 mol of the parent grain emulsion, when the average grain size of the parent grain emulsion is d (μm). It is preferably in the range of 1 / 20,000 d to 1/300 d mol, and most preferably 1/5000 d to 1/500 d mol per 1 mol of the parent grain emulsion.

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

The temperature of the parent grain emulsion when adding silver halide grains is preferably in the range of 30 to 80 ° C., more preferably 40 to 40 ° C.
A range of up to 65 ° C is particularly preferred.

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

Additive RD-17643 RD-18716 RD-308119 Page Classification Page Classification Page Classification Chemical sensitizer 23 III 648 Upper right 996 III Sensitizing dye 23 IV 648-649 996-8 IV Desensitizing dye 23 IV 998 B Dye 25-26 VIII 649-650 1003 VIII Development accelerator 29 XXI 648 Upper right fog inhibitor / stabilizer 24 IV 649 Upper right 1006-7 VI Whitening agent 24 V 998 V Hardener 26 X 651 Left 1004-5 X Surfactant Agent 26-7 XI 650 Right 1005-6 XI Antistatic agent 27 XII 650 Right 1006-7 XIII Plasticizer 27 XII 650 Right 1006 XII Sliding agent 27 XII Matting agent 28 XVI 650 Right 1008-9 XVI Binder 26 XXII 1003-4 IX Support 28 XVII 1009 XVII Supports that can be used in the light-sensitive material of the present invention include, for example, RD-17643, page 28 and RD-308119, 100.
Examples include those described on page 9.

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

[0050]

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

Example 1 A tabular silver halide emulsion EM-was prepared using the solution shown below.
1 was prepared.

[0052] A1 ossein gelatin _{10kg HO- (CH 2 CH 2 O} ) m- [CH (CH ₃₎ CH ₂ O] _{17 - (CH 2 CH 2 O} ) nH (10% methanol solution) m + n = 5.7 Add 0.1l water and 200l B1 silver nitrate 38kg Add water 48l C1 Potassium bromide 26kg Add water 48l While keeping A1 solution at 40 ℃ in a reaction vessel at high speed, p
H was maintained at 5.8, and then, the solution B1 and the solution C1 were added to this solution A1 by the double jet method over 20 minutes.
During this period, the silver potential (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) increased to 140 mV. next
The silver potential was adjusted to 180 mV using a 3.5 N silver nitrate aqueous solution. The pH at this time was 5.9.

Next, the temperature of the liquid in the reaction vessel was raised to 60 ° C., and then the mixture was kept under stirring for 55 minutes. During this period, the silver potential in the reaction vessel was kept at 140 mV using an aqueous potassium bromide solution. p
H was held at 6.0.

To remove excess salts, precipitation desalting was carried out using an aqueous solution of demole (manufactured by Kao Atlas) and an aqueous solution of magnesium sulfate, and additional gelatin was added to obtain an emulsion EM-1.

Observation of the obtained emulsion with an electron microscope revealed that the average side length is 0.87 μm, the variation coefficient is 19%, the average thickness is 0.17 μm, and the average aspect ratio is 5.1. Met.

(Preparation of silver iodide fine grain emulsion) 5000 ml of a 5.2% by weight gelatin solution containing 0.008 mol of potassium iodide
And an aqueous solution containing 1.06 mol of silver nitrate and potassium iodide.
1500 ml was added in a constant amount over 35 minutes. The temperature during the preparation of the microparticles was kept at 40 ° C. When the obtained silver iodide fine grains were confirmed by an electron micrograph at a magnification of 60,000, the average grain size was 0.05 μm and it was a mixture of β-AgI and γ-AgI.

<Formation of Transition Line> The temperature was raised to 45 ° C. before the desalting treatment of the emulsion EM-1 to 1 mol of silver of EM-1. 12% of potassium iodide aqueous solution (0.04 mol / l) equivalent to 1.3 mol%
Added over minutes (step a). Further, 260 ml of 0.4 N silver nitrate aqueous solution and 260 ml of 0.94 N aqueous sodium chloride solution were added over 7 minutes (step b). Further, the temperature is raised to 70 ° C., 0.007 mol (in terms of silver) of the silver iodide fine particles described above is added, and
After stirring for a minute (step c), desalting treatment was performed in the same manner as in EM-1. This emulsion was designated as EM-2.

The step b of the transition line forming step is not carried out, and the step a
The emulsion prepared by carrying out steps c and c was designated as EM-3.

The emulsion prepared by carrying out step c without carrying out steps a and b of the transition line forming step was designated as EM-4.

Dislocation lines of the obtained emulsion were observed with a transmission electron microscope. The accelerating voltage was 200 KV and the temperature was -120 ° C. Table 1 shows the presence / absence of dislocation lines and the results of their positions.

<Chemical Sensitization of Emulsion> Obtained Emulsions EM-1 to EM
While stirring and maintaining -4 at 55 ° C, the following compound (a) was added as a triethanolamine solution so as to be 140 mg per 1 mol of silver in the emulsion, and 10 minutes after that, 1 mol of silver as a chemical sensitizer was added. 60 mg of ammonium thiocyanate, 1.45 mg of chloroauric acid, and 13.8 mg of sodium thiosulfate were added. 30 minutes later, the silver iodide fine grain emulsion described above was added to 1.
After adding 37 × 10 ^-3 mol equivalent, 4-hydroxy-6-methyl-
Stabilization was performed by adding 1,3,3a, 7-tetrazaindene and 1-phenyl-5-mercaptotetrazole, and each was optimally chemically sensitized.

[0062]

[Chemical 1]

The emulsions EM-1 to EM-4 thus obtained were added with the additives described below to prepare emulsion layer coating solutions. At the same time, a protective layer coating solution described below was also prepared. The coating amount is 2.8 silver per side.
g / m ² and the amount with gelatin of 3.6 g / m ² were simultaneously coated on both sides using two slide hopper type coaters at a speed of 80 m / min and dried in 2 minutes and 20 seconds. , Coating samples No. 1 to No. 4 were obtained, respectively. As the support, the copolymer aqueous dispersion obtained by diluting the copolymer consisting of three kinds of monomers of glycidyl methacrylate 50 wt%, methyl acrylate 10 wt%, and butyl methacrylate 40 wt% to 10 wt% is undercoated. 175 μm X as liquid
A polyethylene terephthalate film base colored blue with a density of 0.15 for the line film was used.

The additives used in the emulsion are as follows.
The addition amount is indicated by the amount per mol of silver halide.

1,1-Dimethylol-1-bromo-1-nitromethane 70 mg t-Butyl-catechol 82 mg Polyvinylpyrrolidone (molecular weight 10,000) 1.0 g Styrene-maleic anhydride copolymer 25 g Nitrophenyl-triphenylphosphonium chloride 50 mg 1, Ammonium 3-dihydroxybenzene-4-sulfonate 2.0 g 2-Sodium mercaptobenzimidazole-5-sulfonate 1.5 mg 2-Mercapto- (S-acetyl) succinic anhydride 7.2 mg

[0066]

[Chemical 2]

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

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

[0069]

[Chemical 3]

Sensitometry (evaluation of photographic performance) In sensitometry, a sample was sandwiched between two intensifying screens (NR-160 Konica Corporation), and a tube voltage of 80 kv was applied through an aluminum wedge.
P, tube current 50 mA, X-ray irradiation for 0.05 seconds. Next, using a roller-conveying type automatic developing machine, development and fixing were performed with the developing solution and fixing solution shown below.

The processing time was dry to dry for 90 seconds. The temperature during processing is 32 ° C for development, 33 ° C for fixing, and 20% for washing.
C., and dried at 50.degree. The sensitivity was represented by the reciprocal of the exposure amount that gives a density of fog +1.0, and was represented by the relative sensitivity with the sensitivity of Sample No. 1 being 100. The results are shown in Table 1.

Evaluation of image color tone Each of the obtained samples was X-ray photographed to evaluate the color tone of developed silver.

That is, a fluorescent intensifying screen using a chest phantom
NR-160 (manufactured by Konica Co., Ltd.) was used for actual shooting at a tube voltage of 90 KVp. After photographing, development processing was performed by the same method as in sensitometry.

The obtained real copy sample was observed on a Schaukasten, and the color tone of developed silver due to transmitted light was visually evaluated by the following.

The following visual evaluation was made.

1: Yellowish black 2: Slightly yellowish black 3: Reddish black 4: Slightly reddish black 5: Pure black Evaluation 1 is not practical and evaluation 5 is It is the highest and practically 4 or more.

The results obtained are shown in Table 1 below.

Evaluation of Safelight Fog After irradiation with an incandescent lamp light through a red filter having the transmittance shown in FIG. 1 from 1.2 m above the sample for 30 minutes, development processing was performed by the same processing method as sensitometry and fog was performed. Was measured. The results are shown together in Table 1.

[0079]

[Table 1]

The compositions of the developing solution and fixing solution used in the present invention are shown below.

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

Part-B (for 12 l finishing) Glacial acetic acid 170 g Triethylene glycol 185 g 1-Phenyl-3-pyrazolidone 22 g 5-Nitroindazole 0.4 g N-acetyl-DL-penicillamine 1.2 g Water is added to make 1000 ml.

Starter Glacial acetic acid 120 g Potassium bromide 225 g Water is added to make 1.0 liter.

Fixing Solution Formulation Part-A (For 18l Finishing) Ammonium Thiosulfate (70wt / vol%) 6000g Sodium Sulfite 110g Sodium Acetate Trihydrate 450g Sodium Citrate 50g Gluconic Acid 70g 1- (N, N-Dimethylamino) -Ethyl-5-mercaptotetrazole 18g Add water to make 10 l.

Part-B Aluminum sulfate 800 g Add water to finish to 3.0 l To prepare a developing solution, add Part A and Part B to about 5 l of water at the same time, add water while stirring and dissolve, and add 12 l to finish with glacial acetic acid.
The H was adjusted to 10.40. This is used as a developing solution.

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

The fixing solution was prepared by adding Part A and Part B to about 5 liters of water.
Was added at the same time, water was added while dissolving with stirring to make 18 l, and the pH was adjusted to 4.6 using sulfuric acid and NaOH. This was used as a fixing solution.

Example 2 Seed emulsion EM-0 was prepared using the following solution.

[0089] A2 ossein gelatin _{2kg HO- (CH 2 CH 2 O} ) m- [CH (CH ₃₎ CH ₂ O] _{17 - (CH 2 CH 2 O} ) nH (10% methanol solution) m + n = 5.7 0.1l water was added and 100l B2 silver nitrate 0.85kg water was added 5.0l C2 potassium bromide 0.583kg potassium iodide 0.017kg water was added 5.0l while A2 solution was kept at 40 ° C with high speed stirring in a reaction vessel. pH
Was adjusted to 6.0, and then solution A2 was mixed with solution B2 and solution C2 for 60 seconds by the double jet method. After the addition was completed, the silver potential was 160 mV and the pH was 6.1. After raising the liquid temperature of 60 ° C. to 60 ° C., it was kept stirring for 60 minutes. During this period, the silver potential in the reaction vessel was maintained at 135 mV, and the pH was
Hold on to 6.1.

Next, additional gelatin was added, and the emulsion was cooled and set to be seed emulsion EM-0.

Next, EM-5 was prepared using the following four kinds of solutions.
Was prepared.

[0092] A3 ossein gelatin _{29.4g HO- (CH 2 CH 2 O} ) m- [CH (CH ₃₎ CH ₂ O] _{17 - (CH 2 CH 2 O} ) nH (10% methanol solution) m + n = 5.7 2.5 ml seed emulsion Em-0 0.588 mole equivalent Distilled water to 4800 ml B3 Silver nitrate 1404.2 g Distilled water to 2360 ml C3 Potassium bromide 982.8 g Distilled water to 2360 ml D3 1.75N KBr aqueous solution Silver potential control amount below 60 Using a mixing grinder shown in Japanese Patent Publication Nos. 58-58288 and 58-58289, the total amount of Solution B3 and Solution C3 was adjusted to 21.26 ml / m2 by the double jet method.
At a flow rate of in, it took 80 minutes to carry out additive growth. During this period, the silver potential was controlled to be +70 m by using the solution D3.

After the addition is completed, in order to remove excess salts,
Precipitation desalination was performed using an aqueous solution of Demol N (manufactured by Kao Atlas) and an aqueous solution of magnesium sulfate. A gelatin aqueous solution was added to make 2500 ml, and the mixture was stirred and redispersed.

When the obtained emulsion was designated as EM-5 and EM-5 was observed and measured by an electron microscope and the shape was broken, the average side length was 1.1 μm, the coefficient of variation was 18%, and the average grain thickness was 0.26. μ
The average particle size was m, the average aspect ratio was 4.2, and the main plane was a quadrangular tabular grain.

Emulsion EM-6 was prepared in exactly the same manner as EM-5 except that the amount of potassium bromide in C3 solution used in Emulsion EM-5 was changed to 968 g and the formulation was changed to 20.6 g of potassium iodide. Observation of the obtained EM-6 with a scanning electron microscope revealed that EM-5
The size and shape were almost the same.

<Formation of Dislocation Lines> The temperature of the emulsion EM-5 was raised to 40 ° C. before desalting treatment, and an aqueous solution of potassium iodide equivalent to 1.3 mol% with respect to the silver amount of EM-5 was prepared (0.04 mol / l). Was added over 12 minutes (step d). In addition, 260m1 of 0.4N silver nitrate aqueous solution
260 ml of 0.94N aqueous sodium chloride solution was added over 7 minutes (step e). The temperature was further raised to 75 ° C., 0.008 mol (in terms of silver) of the silver iodide fine particles described above was added, and the mixture was stirred for 10 minutes (step f) and then desalted by the same method as for the emulsion EM-5. . This emulsion was designated as EM-7.

Prior to desalting the emulsion EM-6, the temperature was raised to 40 ° C.
Emulsion EM-8 having a transition line formed was prepared in the same manner as EM-7.

Emulsion EM-without step e of the transition line forming step
The emulsion prepared from 5 was designated as EM-9, and the emulsion prepared from emulsion EM-6 was designated as EM-10.

The emulsion prepared from emulsion EM-5 without carrying out steps d and e of the dislocation line forming step was designated as EM-11, and the emulsion prepared from emulsion EM-6 was designated as EM-12.

The dislocation lines of the obtained emulsion were observed with a transmission electron microscope. The accelerating voltage was 200 KV and the temperature was -120 ° C. The results of presence or absence of dislocation lines and their positions are shown in Table 2 (Chemical sensitization of emulsion). While the emulsions EM-5 to EM-12 thus obtained were stirred and held at 55 ° C, the above compound (a) was added. A triethanolamine solution was added to 140 mg per 1 mol of silver in the emulsion, and 10 minutes later, as a chemical sensitizer, 65 mg of ammonium thiocyanate and 1.45 m of chloroauric acid per 1 mol of silver were added.
g and 15.0 mg of sodium thiosulfate were added respectively. Further, 30 minutes later, the above-mentioned silver iodide fine grain emulsion was 1.37 × 10 ^-3.
After adding a molar equivalent, 4-hydroxy-6-methyl-1,3,3a,
7-Tetrazaindene and 1-phenyl-5-mercaptotetrazole were added to stabilize and optimally chemically sensitize each.

The resulting chemically sensitized emulsions EM-5 to EM-12 were coated on a support and dried in the same manner as in Example 1. The obtained sample was evaluated in the same manner as in Example 1. The results are shown in Table 2.
Shown in.

[0102]

[Table 2]

As is clear from Tables 1 and 2, a silver halide photographic light-sensitive material containing square tabular grains having two parallel (100) planes as main planes has a high maximum density (Dmax) but a silver color. It is in poor condition and has a high level of safe light fog.
However, it can be seen that the silver halide photographic light-sensitive material of the present invention has high sensitivity and a good silver color tone, and further, safe light fog is significantly suppressed.

[0104]

EFFECTS OF THE INVENTION According to the present invention, a silver halide photographic light-sensitive material having high sensitivity, no fog due to safe light when handling a film in a dark room, and a formed silver image having a pure black tone. Got

[Brief description of drawings]

FIG. 1 is a transmittance curve of a red filter for safelight.

Claims (1)

[Claims] 1. A silver halide photographic light-sensitive material having at least one silver halide emulsion layer on at least one side of a support, wherein two silver halide grains in the silver halide emulsion layer are parallel to each other. A silver halide photographic light-sensitive material, which is a tabular silver halide grain having a (100) plane as a main plane and having dislocation lines.