JPS6116053B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a negative silver halide photographic material. (Prior art) Although the supply of metallic silver, which is essential as a raw material for silver halide photographic materials, is decreasing, the demand in various industries is increasing. Attempts are being made actively. Furthermore, various demands are placed on the performance of silver halide photographic materials, and in particular, silver halide photographic materials with stable photographic performance and high or ultra-high sensitivity are required. In particular, in X-ray photosensitive materials, higher sensitivity is required in order to reduce the amount of X-ray exposure to the human body, and photographic photosensitive materials with high image quality are also required. The present inventors have previously proposed (1) a silver halide photographic light-sensitive material for obtaining a negative image, which is capable of greatly reducing silver consumption, and has high sensitivity, high contrast, and a high maximum density. Photosensitive silver halide grains, (2) more easily soluble than the photosensitive silver halide grains in (1),
Moreover, it discloses metal salt particles that have substantially no photosensitivity, which are rendered insoluble by adsorbing an agent to make them insoluble, and (3) particles containing physical development nuclei (JP-A-1988-1999-1).
No. 48544). This negative silver halide photosensitive material is
By processing with a developer containing at least a reducing agent and a substance that dissolves metal salt particles, a blackened image is obtained by depositing a metal corresponding to the metal salt particles on the physical development nuclei located in the exposed area. It is. However, in such silver halide photosensitive materials,
When stored unused (raw storage), sensitivity may decrease or fog may increase. In this case, a specific phenomenon of increased fogging is observed in terms of raw storage stability, especially under high temperature and low humidity conditions. It has also been found that in such silver halide photosensitive materials, the sensitivity can be increased by reducing the amount of the refractory agent added. However, at the same time, the image quality deteriorated, especially the graininess.
Furthermore, deterioration in storage stability also increases. Regarding the desensitization caused by the refractory agent, the present inventors have previously added a refractory agent as a precursor to the above-mentioned negative-working silver halide photosensitive material (Japanese Patent Application Laid-open No. 166642/1983). or added with a non-diffusible refractory agent (Japanese Unexamined Patent Application Publication No. 1989-1999)
66846) was proposed. It has been found that although sensitivity is improved by improving the refractory agent in these previous proposals, raw storage stability, especially increased fog and deterioration of graininess due to storage under high temperature and low humidity, is not improved. (Object of the Invention) The present invention was made in view of the above circumstances, and its first object is to provide a negative type with improved sensitivity of a silver-saving type containing the above-mentioned (1) to (3). The purpose of the present invention is to provide a silver halide photographic material (hereinafter abbreviated as negative material). The second object is to provide a negative light-sensitive material which has greatly improved shelf life, especially fogging and desensitization caused by storage under high temperature and low humidity conditions and high temperature and high humidity conditions. The third object is to provide a negative photosensitive material that has high sensitivity and can produce images with excellent graininess. The fourth object is to provide a negative light-sensitive material that can provide images with high sensitivity, high contrast, and high maximum density, and has a low silver content. (Structure of the Invention) The above-mentioned object of the present invention is to provide a structure in which (1) photosensitive silver halide particles, (2) surfaces of which are made insoluble by an insoluble agent, are present in the constituent layers formed on a support. It itself contains metal salt particles that are more easily soluble than the photosensitive silver halide and have substantially no photosensitivity, (3) and physical development nuclei, and further contains a small amount of a compound represented by the following general formula []. One of the above is added in an amount that does not cause a hardening effect in combination with the photosensitive silver halide grains, and the amount of the refractory agent is 4 x 10 ^-3 mol per 1 mol of the metal salt particles. This can be achieved using a negative photosensitive material having the following characteristics. General formula [] In the formula, A represents a sulfur atom or a selenium atom, B ₁ and B ₂ each represent a group of nonmetallic atoms necessary to form a heterocycle, and X represents an anion. First, to explain the compound represented by the general formula [], the nonmetallic atomic group B ₂ and/or B ₂ necessary to form the heterocycle of this compound is

[Formula] [However, R ₁ represents a hydrogen atom or a lower alkyl group, and m' represents 2 or 3. ] is preferred. Further, preferable heterocycles formed by B ₁ or B ₂ are 5- to 6-membered heterocycles, and heterocycles in which a benzene ring or a naphthyl ring is fused to the heterocycle, and these heterocycles are substituted. Examples of substituents (or atoms) include alkyl groups (e.g. methyl), alkoxy groups (e.g. methoxy), halogen atoms (e.g. chlorine), -
Examples of heterocycles include SO ₃ M group (M represents a hydrogen atom, an alkali metal atom, or an ammonium group), a carboxyl group, a hydroxy group, a sulfamoyl group, etc.

【formula】 【formula】

【formula】

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【formula】

【formula】

【formula】

【formula】

【formula】

[-1]

[-2] [-3] [-4] [-5] [-6] [-7] [-8] [-9] [−10] The compound [] exemplified above can be synthesized by the following method. Synthesis Example 1 (Synthesis Example of Exemplary Compound [-1]) 50 g of 2-methylthiobenzothiazole and 60 g of ethylene bromide were reacted by heating at 160°C for 5 hours,
After cooling, the precipitated crystals were collected by filtration and recrystallized using ethanol to obtain 50 g of the desired product in the form of needle-shaped crystals with a melting point of 258°C.
I got it. Synthesis Example 2 (Synthesis Example of Exemplified Compound [-2]) 50 g of 2-methylthiobenzothiazole and 1,3
- 80 g of dibromopropane was reacted by heating at 160°C for 5 hours, and after cooling, the precipitated crystals were collected by filtration and recrystallized using ethanol to obtain 22 g of the desired product in the form of needle-like crystals with a melting point of 261°C. For example, compounds [-7], [-8] and [-9] are described in Chemical Abstracts, Vol. 72, p. 3166 (1970).
It can be synthesized by the method described in . In addition, the compound [] is usually dissolved in a solvent such as water or methanol to a concentration of 0.1 to 1%, and then
The necessary amount can be added to the photographic emulsion. The addition time may be at any stage during the emulsion preparation process, but it is generally preferable to add it after chemical ripening. The amount added is in the range of 1 to 400 mg, particularly 5 to 200 mg, per mol of the photosensitive silver halide.
is preferred. Compound [] was previously designated as Special Publication No. 47-41095.
No. 48-39169 and No. 49-48172, the compound is known as a compound used in a method for curing proteins, a method for creating hardened gelatin images, and a method for curing vinyl polymers. No suggestion has been made at all. That is, the present invention does not utilize the hardening effect of a binder such as gelatin, and in this point the present invention is clearly different from the prior art. The present invention is characterized in that it is possible to maintain stable photographic performance that cannot be obtained by methods that utilize the hardening action of a binder such as gelatin. To further discuss this point, the amount of compound [] used is 2 mg or less per 1 g of binder such as gelatin contained in the light-sensitive material of the present invention, and this amount is an amount that does not harden the binder. With this addition amount, the melting point of the layer of the photosensitive material to which the compound [ ] is added does not rise, and the object of the present invention is achieved without causing any hardening effect. In addition, photosensitive silver halides used in combination with this compound [] include silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodobromide, silver chloroiodobromide, or mixtures thereof. However, silver iodobromide having high sensitivity is preferably used, and silver iodobromide containing 50 mol % or less of silver iodide is particularly suitable in the present invention. 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 may be manufactured by various manufacturing methods including the usual manufacturing method, such as Japanese Patent Publication No. 46-7772. or as described in the U.S. Patent No.
It can be prepared by the so-called conversion emulsion method described in No. 2592250, such as the single-jet emulsion method and the double-jet emulsion method. 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 microns. This photosensitive silver halide emulsion is then chemically sensitized using various chemical sensitizers. For chemical sensitization, not only known sensitizers such as sulfur sensitizers, selenium sensitizers, and noble metal sensitizers, but also reduction sensitizers, polyalkylene oxide-based sensitizers, etc. can be widely used. can. Furthermore, the photosensitive silver halide emulsion can also be spectrally sensitized using various sensitizing dyes. If necessary, the emulsion may be stabilized by using, in addition to the above-mentioned compounds, known photographic additives such as tetrazaindenes and tetrazoles. Next, when the surface of the metal salt particles used in the present invention is not coated with the refractory agent, the dissolution rate in a substance (described later) that dissolves the metal salt particles is lower than that of the photosensitive halogen. It consists of a metal salt that is larger than silver oxide and has substantially no photosensitivity. That is, to explain in more detail, the dissolution rate (or unit When the mass of the substance dissolved per hour) is measured under the condition that the total mass of the particles contained in both particle groups (A) and (B) is equal, the mass of the substance dissolved per hour is the same as that of particle group (A). ) must be larger than that of ). As a measurement method for actually verifying whether the conditions are met in this way, the following method is suitable. First, two types of emulsions each containing photosensitive silver halide particles and metal salt particles in a hydrophilic colloid are prepared, and each emulsion is coated onto a support and dried to prepare two types of samples. 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, for example, 2 seconds.
There are several levels such as 5 seconds and 8 seconds. Next, the sample is immediately transferred to a water tank, washed with water, and then dried. The residual photosensitive silver halide and residual metal salt amounts of the sample treated in this manner are analyzed and measured by a known method, and the residual rate (%) is determined for each. Draw a graph of residual rate and immersion time, and the miscellaneous rate is 50%.
The immersion time of the photosensitive silver halide sample corresponding to t ₁
and the immersion time t ₂ of the metal salt particle sample, and t ₂ /
Find the value of t ₁ . The value of t ₂ /t ₁ determined in this way needs to be smaller than 1, and preferably smaller than 0.7. The metal salt particles are readily soluble in the sense described above, 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 a metal salt that generally have at most 1/10 the photosensitivity of the photosensitive silver halide. The metal salt particles used in the present invention may be appropriately selected from those having the above properties. However, in a preferred embodiment of the present invention, the metal salt grains are silver halide grains that have substantially no 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 the metal salt particles are non-chemically sensitized silver halide particles. It is preferable that the crystals be finer than the above. The metal salt particles used in the present invention are 0.1 mol to 1 mol per mol of photosensitive silver halide.
Used in a range of 100 moles. 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 surface of the metal salt particles used in the present invention is coated with a refractory agent, which is adsorbed onto the surface of the metal salt particles or forms a part of the particle surface that becomes an active site for the dissolution reaction. It is a compound that slows down the dissolution rate of particles in the presence of the metal salt dissolving agent by adsorbing on the surface of the easily soluble metal salt particles.
It also includes compounds that form poorly soluble salts or complex salts with the metal ions of metal salts. 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, to reduce their solubility. These compounds are preferably, for example, mercapto compounds, more specifically cysteine, 1-phenyl-5-mercaptotetrazole, mercaptobenzthiazole, mercaptobenzselenazole, mercaptobenzoxazole, mercaptobenzimidazole, benzylmercaptan,
4-ethyl-2-thio-oxazoline, 2-mercapto-6-azauracil, 4-hydroxy-2
-Mercapto-6-methyl-pyrimidine, 3-mercapto-4-phenyl-5-methyl-1,2-
Representative examples include 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. As the physical development nuclei used in the present invention, for example, noble metals such as gold, silver, and platinum, preferably colloids thereof, metal sulfides such as silver, palladium, and zinc, or metal selenides can be used. Among these, silver compounds (e.g. silver nitrate,
Particularly preferred are metal silver particles obtained by reducing silver halide, etc., noble metal colloids, palladium sulfide, and silver sulfide. In addition, this physical development nucleus is a metal ion or metal complex ion generated by dissolving the above-mentioned metal salt.
It includes a substance that has the function of catalytically promoting the process of being reduced to a metal by a reducing agent, or a chemically active site that has such a function, and does not necessarily have to be a physical particle. As described above, the content of physical development nuclei in the sensitive material varies depending on the type, but for example, in the case of silver sulfide, it is 0.001 g to 1.0 g/m ² as metallic silver,
For example, in the case of metallic silver (produced by reducing fine particles of silver chloride), a range of 0.01 g to 3.0 g/m ² is appropriate. The negative photosensitive material of the present invention can have various configurations depending on its purpose or use. That is, the negative photosensitive material of the present invention has (1) on the support.
Contains photosensitive silver halide grains, (2) grains in which metal salt grains that are more easily soluble than the silver halide and have substantially no photosensitivity are coated with a refractory agent, and (3) physical development nuclei. However, even if the above (1) to (3) are contained in separate layers, or the above
Any two or more of (1) to (3) 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 particles,
If necessary, the order of stacking may be reversed, starting with a layer structure in which constituent layers containing a silver halide developer (described later) are stacked in the order in which they are stacked. A constituent layer containing development nuclei and, if necessary, a silver halide developer described below is coated, and a constituent layer on which photosensitive silver halide grains and metal salt particles are mixed and present in the same layer. It can be laminated to form a two-layer structure, or a constituent layer in which a mixture of photosensitive silver halide particles, metal salt particles, and physical development nuclei are present in the same layer is coated on a support to form a single layer structure. It can also be configured. In addition, when applying a peel-off diffusion transfer method as another method, the constituent layers may be coated on both sides of the support, or two supports may be prepared and the constituent layers may be applied separately to each support. Alternatively, three supports may be prepared and the constituent layers may be coated one by one on each support. Preferably, the layer structure of the negative photosensitive material of the present invention is coated on the same support as a single layer in which photosensitive silver halide grains, metal salt particles, and physical development nuclei are mixed and present in the same constituent layer. Alternatively, a constituent layer containing a mixture of metal salt particles and physical development nuclei is coated from the support side, and a constituent layer containing only photosensitive silver halide grains is coated on top of this. It is better to have a good structure. The compound [] is contained in combination with the photosensitive silver halide. Therefore, in the case of a layer structure in which photosensitive silver halide grains, metal salt particles, and physical development nuclei are mixed and coated on the same support as a single layer in the same constituent layer, the compound [] is the same. Preferably, it is contained in the layer. In addition, in the case of a layer structure in which a constituent layer is coated by mixing metal salt particles and physical development nuclei from the support side, and a constituent layer containing only photosensitive silver halide particles is coated on top of this, a constituent layer containing only photosensitive silver halide particles is coated. ] is preferably contained in a constituent layer containing only photosensitive silver halide grains. The layer structure of the negative photosensitive material of the present invention is as described above, but if necessary, the negative photosensitive material of the present invention may include auxiliary layers such as a protective layer, an antihalation layer, etc. can be provided,
Further, 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. Furthermore, for the purpose of improving the physical properties of a coated 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 film compositions containing hydrophilic colloid as a binder may optionally contain photographic additives other than the above-mentioned hardeners, such as gelatin plasticizers, surfactants, ultraviolet absorbers, antistain agents, and PH regulators. , antioxidants, antistatic agents, thickeners, graininess improvers, dyes, mordants, brighteners, development speed regulators, matting agents, silver halide developers described below, etc. that may impair the effects of the present invention. It can be used within a certain range. Examples of the support used in the negative photosensitive material of the present invention include baryta paper, polyethylene-coated paper,
Typical examples include polypropylene synthetic paper, glass plates, cellulose acetate, cellulose nitrate, polyester films such as polyethylene terephthalate, polyamide films, polypropylene films, polycarbonate films, and polystyrene films. It is selected as appropriate depending on the purpose of use of the 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., for example, 1-phenyl-3-pyrazolidone,
3-pyrazolidones represented by 1-phenyl-4-methyl-3-pyrazolidone, for example, 0
-Aminophenols represented by aminophenol, p-aminophenol, etc., for example, 1-
(p-hydroxyphenyl)-3-aminopyrazolidone, 1-(p-methylaminophenyl)-3-
1-aryl-3-aminopyrazolines such as aminopyrazoline, ascorbic acid, and others, CEKMees and THJames co-authored “The
Theory of the Photographic Process” 3rd edition (1966, Mecmillan Co., NY), Chapter 13 and LP
Photographic Processing by A. Meson
"Chemistry" (1966, The Focal Press,
Compounds described as developing agents on pages 16 to 30 (London) can be used alone or in combination. A substance that dissolves metal salt particles used in a developer (metal salt dissolving agent) is a substance that acts on 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 water. In this case, the metal salt dissolving agent is a substance that does not substantially dissolve the photosensitive silver halide, or is a substance that does not dissolve the photosensitive silver halide in an amount that does not substantially dissolve the photosensitive silver halide. The material is preferably a substance that dissolves metal salt particles such as silver halide fine particles having different ions. Typical examples of metal salt dissolving agents include sulfites such as sodium sulfite, thiosulfates such as sodium thiosulfate, potassium thiosulfate, and ammonium thiosulfate, cyanates such as potassium cyanide and sodium cyanide, and thiocyanates. thiocyanates such as sodium chloride and potassium rhodan, amino acid compounds such as cystine and cysteine, thiourea, phenylthiourea, 3,6-di-thia-
Thiourea compounds such as 1,8-octadiol,
Examples include thioether compounds. The metal salt dissolving agent is normally contained in the developer, but in some cases it can also be contained in the sensitive material as described above. Among the metal salt dissolving agents mentioned above, sodium sulfite in particular is generally used as a preservative for developing solutions, so the usage amount per unit is 0.1
The amount is preferably in the range of g to 100 g, more preferably 1 g to 70 g. The pH of such a developer is 5 or more, preferably
A pH of about 5.5 to 13.2 is optimal. In addition, if necessary, alkaline agents and pH
Various additives such as buffering agents, development accelerators, and antifoggants can be included. 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 area are reduced by the reducing agent,
The reaction product solubilizes the metal salt particles that have been made difficult to solubilize by the insoluble agent, and dissolves in the presence of the metal salt dissolving agent. The dissolved metal salts are deposited on the physical development nuclei and blacken to form a negative image. Examples Hereinafter, the present invention will be explained in more detail with reference to specific examples. Example 1 [Preparation of photosensitive silver halide emulsion] 4.0 mol % silver iodide that was gold-sensitized and sulfur-sensitized and aged to maximum sensitivity by a conventional method.
As a stabilizer, 4-hydroxy-6-methyl-1,3,
3a,7-tetrazaindene, silver halide 1
A photosensitive silver halide grain emulsion was prepared by adding 1.5 g per mole. The average grain size of this emulsion is approximately
It was 1.3μ. [Preparation of metal salt particles (substantially non-photosensitive silver chloride emulsion)] 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 0.2 μm. [Preparation of physical development nuclei] 1% polyvinyl alcohol (saponification degree 99)
%, polymer with a degree of polymerization of 1000) in 10 ml of an aqueous solution,
After adding 50 ml of 0.2% chloroauric acid and stirring at room temperature, 10 ml of 1% sodium borohydride was added to form a physical development nucleus for gold colloid. First, a silver chloride emulsion with virtually no photosensitivity was divided into four parts from among the three types prepared as described above, and 1-phenyl-5-mercaptotetrazole was added as a difficult-to-solubilize agent at 8x10 per mole of silver chloride. ^-3 moles and 3
x10 ^-3 mol and p-ethoxyphenyl-mercaptotetrazole were added per mol of silver chloride, respectively, 6 x 10 ^-3 mol and 2 x 10 ^-3 mol, and then the above-mentioned physical development nuclei were added to the silver chloride emulsion. After adding 200 mg of chloroauric acid per mole, a suitable amount of saponin was added as a coating aid to prepare a coating solution. Next, the photosensitive emulsion prepared as described above was taken, divided into equal parts, and the compound [ ] was added as shown in Table 1, and then an appropriate amount of saponin was added as a coating aid to each part. It was made into a coating solution. Further, as a protective layer, a 2.5% gelatin aqueous solution containing an appropriate amount of a hardening agent (formalin) and a coating aid (sodium 2-ethylhexyl succinate monosulfonate) was prepared. These coating solutions were uniformly coated on both sides of a subbed polyethylene terephthalate base in the order of silver chloride emulsion, photosensitive silver halide emulsion, and protective layer from the side closest to the base. The amount of coating on both sides of the obtained sample was as follows: the amount of silver in the chloride acid layer as a non-photosensitive silver halide emulsion layer was 1.0 g/m ² , and the amount of gold in the physical development nuclei was 0.8 mg/m ²
The silver content of the silver iodobromide layer as a photosensitive silver halide emulsion layer was 3.0 g/m ² . Next, each sample was subjected to a raw storage test treatment under the conditions shown in Table 1, and then the film piece was wedge-exposed to 3.2 CMS light, and then processed at 20°C using a developer with the following formulation. The film was developed for 4 minutes, then fixed, washed with water, and dried before sensitometry. [Developer prescription] Hydroquinone 9g Anhydrous sodium sulfite 70g Sodium carbonate monohydrate 35g Phenidone 0.4g Potassium bromide 4g Benztriazole 4mg Add water to make 1. The results obtained are shown in Table 1 below. Note that the sensitivity values in the table are shown as a 100 minute ratio with respect to sample No. 1 (naturally left). In addition, the graininess was evaluated visually, with 7 being excellent and 6 being excellent.
The graininess was ranked according to a 7-point system: ``Excellent,'' 5, 'Very Good,' 4, 'Good,' 3, 'Slightly Good,' 2, 'Slightly Poor,' and 1, 'Poor,' with 4 being the practically acceptable graininess.

[Table] As is clear from Table 1, the present invention has higher sensitivity and better graininess than the comparative samples, and is also free from increased fog due to storage at high temperature, low humidity and high temperature, high humidity. It can be seen that the decrease in sensitivity can be greatly improved. Example 2 A coating solution prepared in the same manner as in Example 1 was applied onto a polyethylene terephthalate base. however,
In this case, the hardening agent (formalin) in the protective layer was removed. The melting point of each sample obtained in this way was 0.2N
Measured in an aqueous sodium hydroxide solution. The results are shown in Table 2.

[Table] As shown in the table, the present invention does not increase the melting point. (Effects of the Invention) According to the present invention, a negative image with extremely high sensitivity and excellent graininess can be obtained. In addition, raw storage stability is improved, and the decrease in sensitivity and increase in fog after storage are significantly reduced. In particular, fog caused by raw storage under high temperature and low humidity is significantly reduced.

Claims (1)

[Scope of Claims] 1. In the constituent layers formed on the support, (1) photosensitive silver halide grains, (2) the surface of which is made difficult to solubilize by an agent that makes it difficult to solubilize, and which itself contains the above-mentioned photosensitive silver halide grains. metal salt particles that are more easily soluble than silver halides and have substantially no photosensitivity, (3) and physical development nuclei,
Furthermore, at least one compound represented by the following general formula [] is contained in combination with the photosensitive silver halide grains in an amount that does not cause a hardening effect, and the amount of the refractory agent is as described above. A negative-working silver halide photographic material characterized in that the amount is 4×10 ^-3 mol or less per 1 mol of metal salt particles. General formula [] [In the formula, A represents a sulfur atom or a selenium atom, B ₁ and B ₂ each represent a group of nonmetallic atoms necessary to form a heterocycle, and X represents an anion. ]