JPS6059584B2 - Negative silver halide photographic material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a negative silver halide photographic light-sensitive material.
The present invention relates to a negative-working silver halide photographic light-sensitive material in which deterioration of photographic properties is prevented.

Metallic silver, which is an important raw material for silver halide photographic materials, is a natural product, and while its supply is decreasing year by year, the demand in industry is on the contrary increasing. As a recent trend in the manufacturing technology of silver halide photographic materials, attempts at so-called ``silver saving'', in which the amount of silver used is reduced, are becoming a very important research topic.

From this point of view, the present inventors previously proposed
In No. 8544, the silver content is low and the frequency is high.
A negative-tone photosensitive material with high contrast and maximum density and a processing method thereof have been disclosed. The above method comprises photosensitive silver halide grains and a substantially non-photosensitive metal salt which is more easily soluble than the light-sensitive silver halide grains on the surface using a refractory agent. A photosensitive material containing particles and physical development nuclei is processed with a developer containing a substance that dissolves the metal salt particles.

However, with such materials, the photographic characteristics deteriorate during storage (raw preservation), resulting in a decrease in sensitivity, gamma, etc.
Fog may increase. In this case, it has been found that an unexpected and specific phenomenon occurs in terms of shelf life, particularly in that fog increases significantly under high temperature and low humidity conditions.

In addition, in terms of image quality after processing, graininess,
It has the disadvantage of poor sharpness.

In connection with the above-mentioned photosensitive materials, the present inventors have further developed materials in which a refractory agent is added to the photosensitive material as a recursor, or a material in which a refractory agent is added as a non-diffusive compound, etc. Taku and 56-6684
This was proposed in issue 6. By improving these refractory agents, the decrease in sensitivity has been particularly improved. However, it has been found that the above-mentioned problems such as increased fog and deterioration of graininess with respect to raw storage under high temperature and low humidity conditions cannot be improved. Therefore, the first object of the present invention is to produce a negative film containing photosensitive silver halide grains, substantially non-photosensitive metal salt particles made difficult to solubilize with an insoluble agent, and physical development nuclei as described above. The purpose is to prevent the deterioration of photographic properties, especially the occurrence of fog, when the photosensitive material is stored under high temperature and low humidity conditions, and the second purpose is to prevent the occurrence of high quality such as graininess and sharpness. The purpose is to make it possible to obtain images.

The third objective is to provide a negative-working silver halide photographic light-sensitive material that has good photographic properties immediately after production, provides images with extremely high sensitivity and high contrast, and has a low silver content. It's about doing. The present inventors believe that in order to achieve this purpose, rather than improving the refractory agent,
Based on the idea that it is necessary to improve photosensitive silver halide, the present invention has been completed through intensive research.

That is, as a result of various studies, the inventors of the present invention have prepared photosensitive silver halide grains on a support, the surface of which has been made difficult to solubilize with an agent that makes it difficult to solubilize, and the above-mentioned photosensitive silver halide grains. In a negative-working silver halide photographic light-sensitive material having at least one layer containing metal salt particles and physical development nuclei that are more easily soluble than the above and substantially non-photosensitive, the photosensitive silver halide particles contain 2 mol of the photosensitive silver halide particles. % to 6 mol % of silver iodide, and further contains a compound represented by the following general formula in the layer containing the photosensitive silver halide grains. It has been found that the above objective can be achieved by the following method.

General formula (wherein R represents a linear or branched alkyl group having 1 to 18 carbon atoms.

) Hereinafter, the present invention will be explained in more detail.

As described above, the present invention provides the above-mentioned common materials in the layer containing photosensitive silver halide grains of the negative-working silver halide photographic light-sensitive material of the present invention (hereinafter referred to as the "sensitive material of the present invention") having the above-described layer structure. It is characterized by containing a gallic acid ester compound represented by the formula, and specific examples of the compounds represented by the general formula include the following compounds:
The present invention is not limited to these.

(Exemplary compounds) (1) Gallic acid methyl ester (2) Gallic acid ethyl ester (3) Gallic acid n-propyl ester (4) Gallic acid isopropyl ester (5) Gallic acid n-butyl ester (6) Gallic acid isoamyl ester (7) Gallic acid α-amyl ester (8) Gallic acid n-hexyl ester (9) Gallic acid n-heptyl ester (1Cj1 Gallic acid n-octyl ester (11) Gallic acid n-nonyl ester (12) Gallic acid n -decyl ester (13) gallic acid n-hendecyl ester (14) gallic acid n-dodecyl ester (15) gallic acid n-tetradecyl ester (16) gallic acid n-hexadecyl ester (17) gallic acid n-
Octadecyl ester The above-exemplified compound according to the present invention is generally dissolved in water or a hydrophilic organic solvent such as methanol, ethanol, acetone, etc., and then added to the layer containing the photosensitive silver nitride particles. Added or contained.

The amount of these ester compounds added in the present invention is 10-3 mol to 10-3 mol per 1 mol of photosensitive silver halide.
A range of 1 mole is preferred. If the amount of the compound according to the present invention added is smaller than the above range, it is difficult to obtain the effects of the present invention, and if it is added in a large amount, desensitization may occur, which is not preferable. These compounds may be added at any time during the photosensitive silver halide emulsion production process, but addition after chemical ripening and before coating is advantageous in achieving the object of the present invention. The above compounds according to the present invention may be used alone or in combination of two or more.

Further, the photosensitive silver halide used in the layer containing the photosensitive silver halide grains containing the above-mentioned compound according to the present invention is silver iodobromide, and in particular, the silver iodide content is 2 mol to 6 mol. Silver iodobromide in the mole % range is preferred.
If the silver iodide content is less than the above range, it is difficult to increase the maximum density, and conversely, if it exceeds the above range, the graininess of the negative-working silver halide photosensitive material decreases, which is not preferable in either case. Such photosensitive silver halide grains are applied to the present invention in the form of a silver halide emulsion, but
The emulsion to be used can be manufactured by various manufacturing methods including the conventional post-manufacturing method, such as the method described in Japanese Patent Publication No. 46-77n, or the method described in U.S. Patent No. 2,592.
It can be prepared by the so-called convergence emulsion method, such as the single-jet emulsion method and the double-jet emulsion method, as described in , No. 2.

Further, the photosensitive silver halide grains used in the present invention include those having various crystal habits.

Although the particle size varies depending on the intended use of the photographic element, it is usually within the range of 0.1 to 3.0 .mu.m. This photosensitive silver halide emulsion is then chemically sensitized using various chemical sensitizers.

Chemical sensitizers include known sensitizers such as sulfur sensitizers, selenium sensitizers, and noble metal sensitizers, as well as reduction sensitizers,
Polyalkylene oxide-based sensitizers can also be widely used.

Furthermore, photosensitive silver halide grains can also be spectrally sensitized using various sensitizing dyes.

Further, if necessary, in addition to the compound represented by the above general formula, known photographic additives such as tetrazaindenes and tetrazoles may be used to stabilize the emulsion.

Next, when the surface of the metal salt particles used in the present invention is not coated with the refractory agent,
It is made of a metal salt that has a higher dissolution rate than the photosensitive silver notagenide described above with respect to a substance that dissolves metal salt particles (described later), and has substantially no photosensitivity. That is, to explain in more detail, the dissolution rate (or dissolution rate per unit time) of metal salt particle group A and photosensitive silver halide particle group B in the presence of at least one of the metal salt dissolving agents described below mass of the substance) under the condition that the total mass of particles included in both particle groups A and B is equal to each other,
It is necessary that each particle group A be larger than that of particle group B when measured. The measurement method for actually verifying whether or not these conditions are met is as follows:
The following method is suitable.

First, two types of emulsions containing photosensitive silver halide grains and metal salt grains in hydrophilic colloids were prepared,
Two types of samples are prepared by applying each onto a support and drying.

The amount of coating at this time is such that the amounts of photosensitive silver halide, metal salt, and hydrophilic colloid per unit area are equal between the two types of samples. In the measurement, sodium thiosulfate is used as a standard metal salt dissolving agent, and the obtained sample is immersed in a 5% aqueous sodium thiosulfate solution (temperature 20° C.) without stirring.

The immersion time is set at several levels, for example 2 seconds, 5 seconds and 8 seconds. Next, the sample is immediately transferred to a water tank, washed with water, and then dried. For the sample treated in this manner, the amount of residual photosensitive silver halide and residual metal salt is analyzed and measured by a known method, and the residual rate (%) is determined for each. A graph of residual rate/immersion time is drawn, and the immersion time t1 of the photosensitive silver halide sample and the immersion time t1 of the metal salt particle sample corresponding to a residual rate of 50% are drawn. Find the value of T2/・chi.
The value of T2/t1 determined in this way needs to be smaller than 1, and preferably smaller than 0.7.

The metal salt particles are easily soluble in the above sense, but at the same time they are substantially non-photosensitive.

In this case, in the present invention, "substantially not having photosensitivity" means "not being photosensitized" relative to the photosensitive silver halide, and specifically, It should be understood that when the light energy necessary to sensitize the photosensitive silver halide is applied to the light-sensitive material of the present invention, it is "substantially not sensitized" depending on the light energy.

More specifically, the metal salt particles of the present invention are fine particles of metal salts that generally have a photosensitivity of at most 1110 with respect to the photosensitive silver halide. The metal salt particles used in the present invention may be any metal salt particles that can be appropriately selected from those having the above-mentioned properties.

However, in a preferred embodiment of the present invention, the metal salt grains are silver halide grains that do not have substantial photosensitivity, and compared to the photosensitive silver halide grains, the metal salt grains are made of a substance that dissolves the silver halide grains. Particles are selected that have a high dissolution rate.

More specifically, the metal salt particles preferably applied to the present invention are pure silver bromide, pure silver chloride, or a mixed silver halide thereof that has not been subjected to chemical sensitization treatment, and is It is preferable that the crystals be finer than the above.
The metal salt particles used in the present invention are used in an amount of 0.1 mol to 100 mol per mol of photosensitive silver halide.

In addition, metal ions or metal complex ions produced as a result of dissolving such metal salt particles in the presence of a metal salt dissolving agent described below are reduced to metals in the presence of a reducing agent on physical development nuclei described later. It is something that

The metal salt particles used in the present invention are difficult to obtain. The surface is coated with a solubilizer, and this refractory agent adsorbs to the surface of the metal salt particles or to a part of the particle surface that becomes an active site for the dissolution reaction, thereby reducing the amount of the metal salt solubilizer. There are compounds that slow down the dissolution rate of particles in the presence of this! The poorly soluble agent also includes a compound that adsorbs to the surface of particles of a readily soluble metal salt and forms a poorly soluble salt or a complex salt with the metal ion of the metal salt.

According to one preferred embodiment of the present invention, the refractory agent is selected from compounds that adsorb to non-photosensitive silver halide grains, which are easily soluble metal salt grains, and reduce their solubility.

These compounds are preferably mercapto compounds, more specifically cysteine, 1-phenyl-5-mercaptotetrazole, mercaptobenzthiazole,
Mercaptobenz selenazole, mercaptobenzoxazole, mercaptobenzimidazole, benzyl mercaptan, 4-ethyl-2-thiooxazoline, 2
-mercapto 6-azauracil, 4-hydroxy-2
Typical examples include -mercapto-6-methyl-pyrimidine, 3-mercapto-4-phenyl-5-methyl-1,2,4-triazole, and the like.

Further, thiourea, indazoles, triazoles, imidazoles and the like are also preferred compounds that can be used in the present invention. Among these, mercaptotetrazole compounds are particularly preferred.

On the other hand, physical development nuclei used in the present invention include, for example, noble metals such as gold, silver, and platinum, preferably colloids thereof, metal sulfides such as silver, palladium, and zinc,
Alternatively, a metal selenium compound or the like can be used.

Among these, metal silver particles obtained by reducing silver compounds (for example, silver nitrate, silver halide, etc.), noble metal colloids,
Alternatively, palladium sulfide and silver sulfide are particularly preferred. Note that this physical development nucleus is a substance that has the function of catalytically promoting the process in which metal ions or metal complex ions produced by dissolving the metal salt described above are reduced to metal by a reducing agent, or such a substance. It does not necessarily have to be a physical particle.

The content of such physical development nuclei in a sensitive material varies depending on the type thereof, but for example, in the case of silver sulfide, it is 0.001y to 1.0y/d1 as metallic silver. (manufactured by reducing fine particles of silver chloride),
A range of 0.01y to 3.0y/a is suitable. The structure of the photosensitive material of the present invention can take various forms depending on its purpose or use.

That is, the binder material of the present invention includes (1) photosensitive silver halide grains, (2) a metal salt grain that is more easily soluble than the silver halide and has substantially no photosensitivity, and a refractory agent on the support. and (3) particles containing physical development nuclei, but even if the above (1) to (3) are contained in separate layers, or the above (1) to (3) are Any two or more may be contained in the same layer. For example, on a support, from the support side, a constituent layer containing physical development nuclei, a constituent layer containing metal salt particles, a constituent layer containing photosensitive silver halide grains, and, if necessary, a halogen Starting from the layer structure in which the constituent layers containing the silver oxide developer are laminated in the order, the order of lamination may be reversed, and further, for example, from the support side, the physical development nuclei and the later-described layers are layered as necessary. Coating a constituent layer containing a silver halide developer,
On top of this, a constituent layer in which photosensitive silver halide grains and metal salt particles are mixed and present in the same layer is laminated, and a two-layer structure may be formed. A constituent layer containing a mixture of metal salt particles and physical development nuclei may be coated on a support to form a single layer structure.

Furthermore, as another method, it is possible to coat the constituent layers on both sides of the support, prepare two supports, and form the constituent layers separately for each support, or even coat the constituent layers on both sides of the support. A body may be prepared and the constituent layers may be coated one by one on each support.

The preferable layer structure of the complex material of the present invention is as follows:
A layer structure in which photosensitive silver halide grains, metal salt particles, and physical development nuclei are mixed in the same constituent layer and coated on the same support as a single layer, or metal salt particles and physical development from the support side. It is preferable to form a two-layer structure by coating a constituent layer containing a mixture of nuclei and a constituent layer containing only photosensitive silver halide grains thereon.

The layer structure of the photosensitive material of the present invention is as described above, but the photosensitive material of the present invention may include, if necessary,
For example, auxiliary layers such as a protective layer and an antihalation layer can be provided, and photographic additives other than those mentioned above can also be added to these layers.

In the present invention, the photosensitive silver halide, metal salt particles, and physical development nuclei are each used alone or in a mixture of two or more, dispersed in a suitable binder, and present in a predetermined constituent layer.

Various hydrophilic colloids can be used as the binder, and gelatin is typically preferably used.

In addition, for the purpose of improving the physical properties of a coating film using the above-mentioned hydrophilic colloid as a binder, it is preferable to use various film property improving agents, such as a hardening agent, as necessary.
Coating compositions containing hydrophilic colloid as a binder include:
If necessary, photographic additives other than the hardening agent, such as gelatin plasticizers, surfactants, ultraviolet absorbers, antistain agents, PH regulators, antioxidants, antistatic agents,
Thickeners, graininess improvers, dyes, mordants, brighteners, development speed regulators, matting agents, silver halide developers described below, etc. can be used within the range that does not impair the effects of the present invention. .

Examples of the support used for the surface material of the present invention include (Gibaraita paper, polythousandylene-coated paper, polypropylene synthetic paper, glass plate, cellulose acetate, cellulose nitrate, polyester film such as polyethylene terephthalate, polyamide film, polypropylene Typical supports include film, polycarbonate film, polystyrene film, etc., and each of these supports is appropriately selected depending on the intended use of the photographic element.

After exposure, the photosensitive material of the present invention is processed with a developer containing a reducing agent and a substance that dissolves metal salt particles.

As the reducing agent used in the developer, a developing agent is advantageously used.

As the developing agent, well-known in the art, for example,
Polyhydroxybenzenes represented by hydroquinone, toluhydroquinone, 2,5-dimethylhydroquinone, etc., such as 1-phenyl-3-pyrazolidone,
3-pyrazolidones represented by 1-phenyl-4-methyl-3-pyrazolidone, aminophenols represented by 0-aminophenol, p-aminophenol, etc., such as 1-(p-hydroxyphenyl)- 1-aryl-3-aminopyrazolines represented by 3-aminopyrazolidone, 1-(p-methylaminophenyl)-3-pyrazoline, etc., ascorbic acid, others, C.I. E. K. Mees<15T. H. James
Co-authored “TheOryOfthePhOtOgra
phicPrOcess” 3rd edition J (1966, Ma
cmillanCO. ,N. Y. ) Chapter 13 and L. P.
A. “PhOtOgraphicPrOc” written by MasOn
essingChemistry” (1966, Th
ePOca! Press, [0ndOn) pages 16-30, the compounds described as developing agents can be used alone or in combination. A substance used in a developer that dissolves metal salt particles (metal salt dissolving agent) is a substance that acts on the metal salt particles to generate metal ions or soluble metal complex ions, and this is a substance that dissolves metal salt particles in the developer solution itself. , for example, it may be water.

In this case, the metal salt dissolving agent is a substance that does not substantially dissolve photosensitive silver halide, or is different from photosensitive silver halide in an amount added that does not substantially dissolve photosensitive silver halide. It is preferable to use a substance that dissolves metal salt particles such as silver halide fine particles having different solubility.

Typical specific examples of such metal salt dissolving agents include sulfites such as sodium sulfite, thiosulfates such as sodium thiosulfate, potassium thiosulfate, ammonium thiosulfate, and cyanates such as sodium cyanide and sodium cyanide. , thiocyanate salts such as sodium thiocyanide and potassium rhodasocyanide, amino acid compounds such as cystine and cysteine, thiourea compounds such as thiourea, phenylthiourea, 3,6-di-thia 1,8-octadiol, thioether compounds, etc. can be mentioned.

The metal salt dissolving agent is normally contained in the developer, but in some cases it can also be contained in the developer as described above.

Among the above metal salt dissolving agents, sodium sulfite is generally used as a preservative for developing solutions, so the amount used per 1e is preferably 1y to 70y1. It is preferable that there is a range.

The pH of such a developer is 5 or more, preferably PH5.
．． Approximately 5 to 131 is optimal. Further, the developer may contain various additives such as an alkaline agent, a PH buffer, a development accelerator, and an antifoggant, if necessary.

The processing temperature using the above-mentioned processing liquid is suitably in the range of 20°C to 50°C. By processing with such a developer,
The photosensitive silver halide grains in the exposed areas are reduced by the reducing agent, and the resulting halogen ions, particularly bromine or iodine, destroy the coating of the refractory agent present on the surface of the metal salt.

As a result, the metal salt particles are dissolved in the presence of the metal salt dissolving agent,
It is deposited on the physical development nucleus and becomes black, forming a negative image.

Note that processing after development may be carried out in accordance with commonly used processing for black-and-white materials, such as stopping and fixing. According to the present invention, 2 mol% of the compound represented by the above general formula
By incorporating it in combination with photosensitive silver halide grains made of silver iodobromide containing ~6 mol% silver iodide, the shelf life of the photosensitive material is improved, and the sensitivity, gamma, and maximum density after storage are improved. There is very little deterioration.

In particular, fog caused by raw storage under high temperature and low humidity is significantly reduced.

Furthermore, image quality such as graininess and sharpness of the obtained image is also improved.

In addition, the photographic properties immediately after manufacture are good, with high sensitivity and
High contrast images can be obtained.

As a result, a negative photosensitive material is realized that can stably produce images of excellent overall quality. Hereinafter, the present invention will be explained in more detail with reference to specific examples.

Example 1 [Preparation of photosensitive silver iodobromide emulsions] High-strength silver iodobromide emulsions containing various concentrations of gold-sensitized and sulfur-sensitized silver iodide were prepared by conventional methods. ,
As a stabilizer, 4-hydroxy-6-methyl-1,3,
A photosensitive silver halide grain emulsion was prepared by adding 1.5 y of 3a,7-tetrazaindene per mole of silver halide.

The average grain size of this emulsion is approximately 1. '2p was hot. [Preparation of metal salt grains (substantially non-photosensitive silver halide grains)] A pure silver chloride emulsion consisting of silver nitrate and sodium chloride was prepared by a neutral method.

The average grain size of this emulsion was easily soluble silver chloride grains of about 0.1 μm.

[Preparation of physical development nuclei]

Add 0.2% to 10ml of an aqueous solution of 1% polyvinyl alcohol (a polymer with a degree of saponification of 99% and a degree of polymerization of 1000).
Add 50ml of chloroauric acid of 1% to the stirred mixture at room temperature.
10 ml of sodium borohydride was added to form a physical development nucleus for gold colloid.

First, a silver chloride emulsion with substantially no photosensitivity was taken from among the three types prepared as described above, and 1-phenyl-5-mercaptotetrazole was added to the silver halide emulsion as an insoluble agent.
Then, 120 ml of the above-mentioned physical development nuclei as chloroauric acid was added per mole of silver chloride emulsion, and then an appropriate amount of saponin was added as a coating aid to prepare a coating solution.

At the time of application, it was applied uniformly to both sides of a polyethylene terephthalate base that had been subjected to undercoat processing. Subsequently, the photosensitive emulsion prepared as described above is collected and divided into equal parts, and then the compound represented by the general formula in the present invention is added to
Samples with additives as shown in Table 1 below and samples with no additives were prepared for comparison.

Next, after adding appropriate amounts of saponin as a coating aid and formalin as a hardening agent to each of the above samples,
A sample was prepared by uniformly coating both sides of the silver chloride emulsion layer.

The amount of coating on both sides of the obtained sample was such that the amount of silver in the silver chloride layer as a non-photosensitive silver halide emulsion layer was 1.0 y/i, the amount of physical development nuclei was 1.0 m9/i in terms of gold, and the amount of photosensitive The amount of silver in the silver iodobromide layer as a silver halide emulsion layer is 2.5y.
It was /d.

For each of the above samples, after storing them under high temperature, low humidity and high temperature and high humidity conditions, double-sided wedge exposure was performed using 3.2 CMS light, and then development was performed at 20°C for 4 minutes and 30 seconds using a developer with the following formulation. conduct.

After fixing, washing with water and drying, sensitometry was performed and the results are shown in Table 1. (Developer Composition) The sensitivities in Table 1 below are expressed as relative values with the sensitivity of Sample 1 as 100.

As is clear from Table 1 above, the combination of silver halide grains with a relatively high silver iodide content and the compound according to the present invention produces particularly high yields compared to the comparative samples (Samples Nos. 1 to 4). It was found that the maximum density could be maintained during storage without decreasing sensitivity or increasing fog.

Example 2 Samples were prepared by combining light-sensitive silver halide emulsions having various silver iodide contents as shown in Table 2 below and compounds according to the present invention by the same method as in Example 1. It was created.

The obtained sample was developed in the same manner as in Example 1, and the resulting photographic properties are shown in Table 2 below. The graininess is visually determined according to a 7-step system: 7 is excellent, 6 is excellent, 5 is slightly excellent, 4 is good, 3 is slightly good, 2 is slightly poor, and 1 is poor. The graininess that is practically acceptable is 4.

From the results shown in Table 2 above, photosensitive silver halide emulsions with a low silver iodide content have a low maximum density, and when the silver iodide content is high, the graininess of the silver halide emulsion decreases.

However, it has been found that by combining a silver halide emulsion having a content according to the present invention with a compound according to the present invention, a photographic material having a high maximum density and excellent graininess can be obtained. Next, three types of photosensitive materials created in this way. , tube voltage 100KVP. Tube current 100rr
Image sharpness and granularity were measured for a sample obtained by irradiating X-rays under 1A conditions and processing in the same manner as in Example 1.

For the sharpness, use 0TF, and place a 0TF measurement chart containing a lead rectangular wave of 0.8 to 10 lines/7 m closely to the back side of the front side of the intensifying screen, and measure the lead rectangular wave on the film surface. The film was developed by irradiating X-rays so that the density of the unshielded area was 1.0 on both sides.

Next, the emulsion layer on the front side with respect to the X-ray generator is peeled off, and the rectangular wave pattern on the other side is
Measurement was performed using Sakura Microdensitometer M-5 type (manufactured by Konishiroku Photo KK). The aperture size at this time is 230p in the parallel direction of the rectangular wave and 2? in the perpendicular direction. The magnification was set to IOPJ.

The results obtained for samples NO19 (comparative sample), 20 (comparative sample) and 23 (sample according to the invention) are
As shown in the figure.

On the other hand, the graininess was measured by placing an acrylic plate with a thickness of 10 cm in front of the photosensitive material sandwiched between amplifying paper, and performing X under the above conditions so that the density after development was 1.0 on both sides. It was irradiated with radiation.

Next, in the same manner as in the 0TF measurement, the emulsion layer on one side was peeled off, and the RMS value was measured on the other side using a Sakura one-touch RMS measuring device (manufactured by Konishiroku Photo Industry KK).

Note that the aperture size at this time was 50p, and the magnification was 5×l.

The results obtained are shown in Table 3.

As is clear from the results shown in FIG. 1 and Table 3, the optical material of the present invention was found to have extremely good sharpness and graininess.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the relationship between spatial frequency and 0TF value for confirming the sharpness-related effects of the present invention.

Claims (1)

[Scope of Claims] 1. Photosensitive silver halide grains on a support, the surface of which has been made difficult to solubilize with an insoluble agent, are themselves more easily soluble than the above-mentioned photosensitive silver halide grains, and substantially In a negative-working silver halide photographic light-sensitive material comprising one or more layers comprising metal salt particles having no photosensitivity and a layer containing physical development nuclei, the photosensitive silver halide particles are A negative characterized in that it is silver iodobromide containing 2 mol % to 6 mol % of silver iodide, and further contains a compound represented by the following general formula in the layer containing the photosensitive silver halide grains. type silver halide photographic material. General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R represents a straight chain or branched alkyl group having 1 to 18 carbon atoms.)