JPH0411853B2 - - Google Patents

Description

[Detailed description of the invention]

(A) Field of Industrial Application The present invention relates to a method for developing a silver halide photographic material, and particularly to a photographic material that provides extremely high contrast negative images, highly sensitive negative images, and good halftone image quality. . (B) Prior art The addition of hydrazine compounds to silver halide photographic emulsions and developing solutions is described in U.S. Pat. (Using hydrazine as an auxiliary developer to obtain an image), Specification No. 3386831 (containing β-monophenyl hydrazide of aliphatic carboxylic acid as a stabilizer for silver halide sensitive materials), Specification No. 2419975, etc. ,
“The Theory of Photographic” by Mees
Process” 3rd edition (1966) 281 pages. Among these, in particular U.S. Patent No. 2,419,975,
It is disclosed that a high contrast negative image can be obtained by adding a hydrazine compound. That is, it is stated that when a hydrazine compound is added to a silver chlorobromide emulsion and the emulsion is developed with a developer having a high pH of 12.8, extremely high-contrast photographic characteristics with a gamma (γ) exceeding 10 can be obtained. . However, strong alkaline developers with a pH close to 13 are susceptible to air oxidation, are unstable, and cannot withstand long-term storage or use. The ultra-high contrast photographic characteristics with a gamma value exceeding 10 are extremely useful for photographic reproduction of continuous-tone images using dot images useful in printing plate making, and reproduction of line drawings, whether negative or positive images. Useful. Conventionally, for this purpose, a silver chlorobromide emulsion with a silver chloride content exceeding 50 mol%, preferably 75 mol%, is used, and the effective concentration of sulfite ions is extremely low (usually 0.1 mol/%). A method of developing with a hydroquinone developer (Lith development) was commonly used. However, in this method, the developer is extremely unstable due to the low sulfite ion content in the developer,
It cannot withstand being stored for more than a day. Furthermore, since all of these methods require the use of silver chlorobromide emulsions having a relatively high silver chloride content, high sensitivity cannot be obtained. Therefore, there has been a strong desire to obtain ultra-high contrast photographic characteristics useful for reproducing halftone images and line drawings by using a highly sensitive emulsion and a stable developer. For this purpose, U.S. Pat.
No. 4224401, No. 4243739, No. 4269929, No. 4224401, No. 4243739, No. 4269929, No.
No. 4272614, No. 4323643, etc., disclose silver halide photographic materials that use a stable developer to provide extremely high-contrast negative photographic properties. It has been found that it has some drawbacks. That is, these hydrazines are known to generate nitrogen gas during the development process, and this gas may collect in the film and form bubbles, which may damage the photographic image. Therefore, there has been a desire for a compound which can reduce the generation of bubbles and at the same time reduce the cost of producing a sensitive material, and which can provide extremely sharp photographic characteristics even when added in a small amount. Also, if development is continued using these hydrazines, countless circular fogs (sand fog; pepper fog) will appear in the unexposed areas.
This was likely to occur, significantly impairing image quality. In addition, conventional hydrazines are required in large amounts for sensitization and high contrast, and when particularly high sensitivity is required in terms of the performance of the photosensitive material, other sensitization techniques [e.g. chemical Increasing sensitization; increasing particle size; US Pat. No. 4,272,606 and US Pat. No. 4,241,164
However, when these sensitization techniques are used together, sensitization over time and sensitization fog may occur during storage. be. Furthermore, when conventional hydrazines are used for development, so-called uneven development is likely to occur due to uneven stirring of the developer. This development unevenness is noticeable in automatic processor processing, and if the development processing is strengthened to eliminate this phenomenon, the above-mentioned sand fog phenomenon occurs, which is a drawback. Therefore, there has been a desire for a compound that does not have the problems of stability over time, uneven development, or sand fog as described above, is effective when added in a very small amount, and is easy to synthesize. (C) Purpose of the Invention The first purpose of the present invention is to provide a silver halide photographic light-sensitive material capable of obtaining photographic characteristics of extremely high contrast negative gradation with a gamma of over 10 using a stable developer. That's true. A second object of the present invention is to provide a negative-working silver halide photographic material containing hydrazines that can provide good image quality without problems with uneven development or sand fog. A third object of the present invention is to provide a negative-working silver halide photograph containing hydrazines that can provide the desired photographic characteristics of extremely high contrast negative gradation with a small amount of addition without adversely affecting photographic performance. The purpose of this invention is to provide photosensitive materials. A fourth object of the present invention is to improve the processing stability (e.g., no development unevenness, sand fog, etc.) by adding hydrazines, which can provide photographic properties such as rapid sharp contrast, to the processing solution. An object of the present invention is to provide a method for developing a silver oxide photographic material with high contrast. (D) Structure of the Invention The objects of the present invention were achieved by developing a silver halide photographic material in the presence of a compound represented by the following general formula (). General formula () [Wherein, Ar represents an aryl group, and R represents a hydrogen atom, an alkyl group, an alkenyl group, an unsaturated heterocyclic group, or an aryl group. R ₁ and R ₂ represent a hydrogen atom or a group represented by the general formula (). ] General formula () [In the formula, R ₀ represents an alkyl group, an alkenyl group, an aryl group, an alkoxy group, or an aryloxy group, and n represents an integer of 1 or 2. ] In the general formula (), the aryl group represented by Ar is specifically a phenyl group or a naphthyl group which may have a substituent, and examples of the substituent include an alkyl group, an aryl group, group, halogen atom, alkoxy group, aryloxy group, alkenyl group, substituted amino group, acylamino group, sulfonamide group, alkylidene amino group, thiourea group,
Examples include a thioamide group, a heterocyclic group, and a combination thereof. In the general formula (), among the groups represented by R,
Alkyl groups and alkenyl groups are preferably
Alkyl groups and alkenyl groups having 30 or less carbon atoms, including halogen atoms, cyano groups, carboxy groups,
It may have a substituent such as an alkoxy group (including a polyether group), an aryloxy group, a sulfo group, an aryl group, or a substituted amino group. In the general formula (), among the groups represented by R,
The aryl group is a phenyl group or a naphthyl group which may have a substituent. Examples of preferred substituents include an alkyl group, an aryl group, a halogen atom, an alkoxy group, an aryloxy group, an alkenyl group, a substituted amino group, an acylamino group, a sulfonamide group, an alkylidene amino group, a heterocyclic group, or a combination thereof. etc. Among the groups represented by R in the general formula (), an unsaturated heterocyclic group may be combined with a monocyclic or bicyclic aryl group to form a heteroaryl group. In the general formula (), among the groups represented by R ₀ ,
Alkyl and alkenyl groups preferably have carbon atoms
30 or less alkyl and alkenyl groups,
It may have a substituent such as a halogen atom, a cyano group, an alkoxy group, an aryloxy group, an aryl group, or a substituted amino group. In the general formula (), among the groups represented by R ₀ ,
The aryl group is a phenyl group or a naphthyl group which may have a substituent, and examples of the substituent include an alkyl group, an aryl group, a halogen atom,
Examples include an alkoxy group, an aryloxy group, a combination thereof, and the like. Among the groups represented by R ₀ in the general formula (),
The alkoxy group is preferably an alkoxy group having 1 to 8 carbon atoms, and may be substituted with a halogen atom, an aryl group, or the like. In the general formula (), the aryloxy group in the group represented by R ₀ is preferably a monocyclic group, and may be substituted with a halogen atom, an alkyl group, or the like. Ar or R in the general formula () may have a ballast group commonly used in immobile photographic additives such as couplers incorporated therein. The ballast group is a group having 8 or more carbon atoms and is relatively inert to photography, such as an alkyl group, an alkoxy group, a phenyl group, a phenoxy group,
You can choose from among these. Specific examples of the compound represented by the general formula () are shown below. However, the present invention is not limited to the following compounds. The compounds of the present invention can be synthesized by various methods. For example, the corresponding hydrazine compound (Ar
_-NHNH2 ) and a compound represented by the general formula () in a suitable solvent such as dioxane, benzene, DMF, etc. under a base catalyst or by simply heating. General formula () [In the formula, R is defined in the general formula (), and X represents a halogen atom, a phenoxy group, a succinimide group, a phthalimide group, or the like. ] Further, as another method, a method using a transesterification reaction as shown in the synthesis example, a method of reacting ascorbic acid with a corresponding diazonium salt, etc. can be used. The method for synthesizing the compound of the present invention will be explained below by giving specific examples. <Synthesis Example 1> Synthesis of Exemplified Compound 1 150 ml of diethyl oxalate was added to 30.7 g of p-nitrophenylhydrazine, and the mixture was heated and stirred on a water bath at about 80° C. for 1 hour. After cooling, 50 ml of isopropyl ether was added to the reaction solution to precipitate crystals. The obtained crude crystals were recrystallized from an ethyl acetate-benzene mixture to give 1-ethoxalyl-2-(p
40.6 g of -nitrophenyl)hydrazine was obtained. Melting point: 187.0-187.5°C Next, 25.3 g of 1-ethoxalyl-2-(p-nitrophenyl)hydrazine obtained above was dissolved in ethanol.
After dissolving in a mixed solvent of 300 ml and dioxane 200 ml, 20 g of 10% palladium-carbon was added and catalytic reduction was carried out in the usual manner to obtain 1-ethoxalyl-2-(p-
21.5 g of (aminophenyl)hydrazine was obtained. melting point
97-99℃ Next, 11.2g of 1-ethoxalyl-2-(p-aminophenyl)hydrazine obtained above was added to ethanol.
After dissolving in 200 ml, 10.9 g of pn-hexyloxybenzaldehyde was added and stirred overnight at room temperature. After the reaction, the precipitated crystals were collected by filtration and recrystallized from about 1 liter of ethanol to obtain Exemplary Compound 1. Yield: 19.8g Melting point: 206.0-207.0℃ (Elemental analysis) C% H% N% Theoretical value: 67.13 7.10 10.21 Measured value: 67.10 7.08 10.35 <Synthesis example 2> Synthesis of exemplified compound 4 Add 13ml of diethyl oxalate to 10ml of cyclohexane Add 1.4 ml of triethylamine and add p-methoxyphenylhydrazine hydrochloride while stirring at room temperature.
1.75g was added in portions. After the addition, the mixture was heated under reflux for 1 hour. After cooling, the precipitated crystals were collected by filtration, washed with water and dried. The obtained crude crystals were recrystallized from a mixed solvent of ethyl acetate and cyclohexane to obtain Exemplary Compound 4. Yield: 1.6g Melting point: 130.0-131.5℃ (Elemental analysis) C% H% N% Theoretical value: 55.46 5.92 11.76 Measured value: 55.41 5.93 11.68 <Synthesis example 3> Synthesis of exemplified compound 6 8.45g of L-ascorbic acid was added to water Dissolve the solution in 85ml and 4-methylbenzenediazonium sulfate in water.
The solution dissolved in 120 ml was mixed and stirred at room temperature for 1 hour. After cooling the reaction solution with ice, the precipitated crystals were collected by filtration, washed with cold water, and dried to obtain pale yellow crystals. Yield: 11.3g Melting point: 180.5-182.5℃ (Elemental analysis) C% H% N% Theoretical value: 53.06 4.80 9.52 Measured value: 53.00 4.96 9.65 <Synthesis example 4> Synthesis of exemplified compound 7 9.23g of L-ascorbic acid in water A solution prepared by dissolving 4-methoxybenzenediazonium sulfate in 90 ml of water and a solution obtained by dissolving 4-methoxybenzenediazonium sulfate in 110 ml of water were mixed and stirred at room temperature for 1 hour. After cooling the reaction solution on ice, the precipitated crystals were collected by filtration.
After washing with cold water, the mixture was dried to obtain Exemplified Compound 7 as pale yellow crystals. Yield: 10g Melting point: 175.5-177℃ (Elemental analysis) C% H% N% Theoretical value: 50.32 4.55 9.03 Measured value: 50.30 4.36 9.16 <Synthesis Example 5> Synthesis of Exemplary Compound 8 Exemplary Compound 7 obtained in Synthesis Example 4 A solution of 1.55 g dissolved in 20 ml of dioxane and a solution of 0.13 g of metallic sodium dissolved in 5 ml of anhydrous n-octyl alcohol were mixed, and the mixture was heated and stirred on a water bath at 80 to 90° C. for 4 hours. After cooling, insoluble materials were filtered off, and the filtrate was concentrated under reduced pressure. The resulting residue was recrystallized from a mixed solvent of cyclohexane and ethyl acetate to obtain Exemplary Compound 8. Yield: 0.97g Melting point: 89.5-92.5℃ (Elemental analysis) C% H% N% Theoretical value: 63.33 8.13 8.69 Measured value: 63.32 8.20 8.73 <Synthesis example 6> Synthesis of exemplified compound 10 p-Tolylhydrazine hydrochloride 2.38g in THF30
ml, then 2.43 ml of pyridine was added, and a solution of 3.31 g of octyl chloroglyoxylate dissolved in 15 ml of THF was slowly added dropwise while cooling in a dry ice-methanol bath. After dropping, at the same temperature
After stirring for a period of time and filtering off the precipitate, the filtrate was concentrated under reduced pressure and subjected to silica gel column chromatography to obtain the target exemplary compound 10. Yield: 2.8g Melting point: 114.0-115.0℃ (Elemental analysis) C% H% N% Theoretical value: 66.64 8.55 9.14 Measured value: 66.64 8.60 9.13 <Synthesis example 7> Synthesis of exemplified compound 11 4-(4-tert-butylphenoxy ) - phenylhydrazine hydrochloride 2.92g and diethyl oxalate
After adding 10 ml of cyclohexane and 1.39 ml of triethylamine to 14.61 g, the mixture was heated under reflux for 3 hours. After the reaction was completed, the reaction solution was poured into water and extracted with ethyl acetate. After drying over sulfur salt, the ethyl acetate was concentrated under reduced pressure. Exemplary Compound 11 was obtained by recrystallizing the obtained residue from a mixed solvent of cyclohexane and ethyl acetate. Yield: 2.6g Melting point: 117.0-118.0℃ (Elemental analysis) C% H% N% Theoretical value: 67.40 6.79 7.86 Measured value: 67.31 6.80 7.93 In the photosensitive material of the present invention, the compound represented by the general formula () is: It is preferably contained in the surface latent image type silver halide emulsion layer, but it may be contained in the hydrophilic colloid layer adjacent to the surface latent image type silver halide emulsion layer. Such layers include a subbing layer, an intermediate layer, a filter layer,
The layer may have any function, such as a protective layer or an antihalation layer, as long as it does not prevent the compound represented by the general formula () from diffusing into the silver halide grains. The content of the compound of the invention in the layer varies depending on the properties of the silver halide emulsion used, the chemical structure of the compound and the development conditions, so the appropriate content may vary over a wide range. , about 1×10 ^-6 per mole of silver in the surface latent image type silver halide emulsion.
A range of 1.times.10.sup. ^-2 moles is practically useful. When mixed in the developer with the hydrazine compound represented by the general formula () used in the present invention, the appropriate amount is 10 ^-4 to 10 ^-1 mol/l, more preferably 5 x 10 ^-4 A range of from 5×10 ^{−2 /l to 5×10 −2} /l is particularly preferred. The silver halide used in the light-sensitive silver halide emulsion layer of the light-sensitive material of the present invention is not particularly limited, and silver chlorobromide, silver chloroiodobromide, silver iodobromide, silver bromide, etc. can be used. However, when silver iodobromide or silver chloroiodobromide is used, the content of silver iodide is preferably in the range of 5 mol % or less. There are no particular limitations on the morphology, crystal habit, size distribution, etc. of the silver halide grains, but grain sizes of 0.7 microns or less are preferred. Silver halide emulsions are made of gold compounds such as chlorauric acid salts and gold trichloride, salts of noble metals such as rhodium and iridium, sulfur compounds that react with silver salts to form silver sulfide, stannous salts, etc. Sensitivity can be increased by using reducing substances such as amines without making the particles coarser. Also, salts of noble metals such as rhodium and iridium,
Iron compounds such as red blood salts may also be present during physical ripening or nucleation of the silver halide grains. In particular, the addition of rhodium salts or complex salts is preferable because it further promotes the effect of the present invention of achieving ultra-high contrast photographic characteristics in a short development time. In the present invention, the surface latent image type silver halide emulsion refers to an emulsion comprising silver halide grains having surface sensitivity higher than internal sensitivity, and this emulsion is preferably defined in US Pat. No. 4,224,401. There is a difference between surface sensitivity and internal sensitivity. It is desirable that the silver halide emulsion be monodisperse, particularly an emulsion having the monodispersity defined in the above-mentioned US Pat. No. 4,224,401. The photographic emulsion used in the present invention may be spectrally sensitized with methine dyes or others. The dyes used include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, and hemioxonol dyes. Particularly useful dyes are those belonging to the cyanine dyes, merocyanine dyes, and complex merocyanine dyes. These sensitizing dyes may be used alone, but
Combinations thereof may also be used. Combinations of sensitizing dyes are often used, especially for the purpose of supersensitization. Along with the sensitizing dye, the emulsion may contain a dye that itself does not have a spectral sensitizing effect or a substance that does not substantially absorb visible light and exhibits supersensitization. As the binder or protective colloid that can be used in the emulsion layer or intermediate layer of the light-sensitive material of the present invention, it is advantageous to use gelatin, but other hydrophilic colloids can also be used. For example, gelatin derivatives, graft polymers of gelatin and other polymers, proteins such as albumin and casein; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, and cellulose sulfates; sugar derivatives such as sodium alginate and starch derivatives; polyvinyl alcohol , partial acetal of polyvinyl alcohol, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole, etc., using various synthetic hydrophilic polymer materials such as single or copolymers. be able to. Gelatin includes lime-processed gelatin, acid-processed gelatin, Bull, Soc, Sci, Phot, Japan
Enzyme-treated gelatin as described in No. 16, P30 (1966) may be used, and gelatin hydrolysates and enzymatically decomposed products may also be used. The photographic emulsion used in the present invention can contain various compounds for the purpose of preventing fog during the manufacturing process, storage, or photographic processing of the light-sensitive material, or for stabilizing photographic performance. That is, azoles such as benzothiazolium salts, nitroimidazoles, nitrobenzimidazoles, chlorobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptothiazoles, aminotriazoles, benzotriazoles, mercaptotetrazoles. ; Mercaptopyrimidines, mercaptotriazines, thioketo compounds; Azaindenes; Many compounds conventionally known as antifoggants or stabilizers can be added. Among these, particularly preferred are benzotriazoles (eg, 5-methylbenzotriazole) and nitroindazoles (eg, 5-nitroindazole). These compounds may be included in the treatment liquid. The photographic light-sensitive material of the present invention may contain an inorganic or organic hardening agent in the photographic emulsion layer or other hydrophilic colloid layer. For example, chromium salts (chromium alum, etc.), aldehydes (formaldehyde, glyoxal, etc.), N-methylol compounds, dioxane derivatives (2,3-dihydroxydioxane, etc.),
Active vinyl compounds, active halogen compounds (2,4
-dichloro-6-hydroxy-S-triazine, etc.), etc. can be used alone or in combination. The photographic emulsion layer or other hydrophilic colloid layer of the light-sensitive material produced using the present invention may contain coating aids, antistatic properties, smoothness improvement, emulsification dispersion, adhesion prevention, and improvement of photographic properties (e.g., development acceleration, high contrast). (sensitization, sensitization)
Various surfactants may be included for various purposes such as. For example, saponins (steroids), alkylene oxide derivatives (polyethylene glycol, polyethylene glycol alkyl ethers, etc.),
Nonionic surfactants such as glycidol derivatives (alkenylsuccinic acid polyglycerides, etc.), fatty acid esters of polyhydric alcohols, alkyl esters of sugars; alkyl carboxylates, alkyl sulfonates, alkyl sulfates, alkyl Carboxy groups, such as phosphoric acid esters,
Anionic surfactants containing acidic groups such as sulfo groups, phospho groups, sulfate ester groups, phosphate ester groups;
Ampholytic surfactants such as amino acids, aminoalkyl sulfonic acids, aminoalkyl sulfates or phosphoric acid esters; Cations such as aliphatic or aromatic quaternary ammonium acids, heterocyclic quaternary ammonium salts such as pyridinium and imidazolium Surfactants can be used. In the photographic light-sensitive material used in the present invention, a hydrophilic colloid layer such as a photographic emulsion layer may contain a decomposed product of a water-insoluble or sparingly soluble synthetic polymer for the purpose of improving dimensional stability. For example, alkyl (meth)acrylate, alkoxyalkyl (meth)acrylate, glycidyl (meth)acrylate, (meth)acrylamide, vinyl acetate, acrylonitrile, olefin, styrene, etc. alone or in combination, or together with acrylic acid, methacrylic acid, α , β-unsaturated dicarboxylic acid, hydroxyalkyl (meth)acrylate, sulfoalkyl (meth)acrylate, styrene sulfonic acid, etc. can be used as a monomer component. In order to obtain ultra-high contrast photographic characteristics using the silver halide photosensitive material of the present invention, it is not necessary to use a conventional Lith developer or a high alkaline developer with a pH close to 13 as described in U.S. Pat. No. 2,419,975. , a stable developer can be used. That is, the silver halide photographic material of the present invention is
Sufficient amount of sulfite ion as a preservative (especially 0.15
In addition, a developer with a pH of 9.5 or higher, particularly 10.5 to 12.3, can be used to obtain a sufficiently high contrast negative image. There are no particular limitations on the developing agent that can be used in the method of the present invention, and dihydroxybenzenes, 3-pyrazolidones, aminophenols, and the like can be used alone or in combination. The developer also contains alkali metal sulfites,
PH buffering agents such as carbonates, borates, and phosphates; development inhibitors or antifoggants such as bromides, iodides, and organic antifoggants (particularly preferably nitroindazoles or benzotriazoles); It can also contain agents such as Also, if necessary, water softeners, solubilizing agents, toning agents, development accelerators, surfactants, antifoaming agents, hardeners, film silver stain preventive agents (for example, 2-mercaptobenzimidazole sulfonic acids) It may also include. Specific examples of these additives are described in Research Disclosure No. 176, 17643, and the like. As the fixer, one having a commonly used composition can be used. As the fixing agent, in addition to thiosulfates and thiocyanates, organic sulfur compounds known to be effective as fixing agents can be used. Further, the fixing solution may contain a water-soluble aluminum salt or the like as a hardening agent. In the present invention, a method may be adopted in which a developing agent is incorporated into the photosensitive material and the material is processed with an alkaline activator solution. (JP-A No. 57-129436, No. 57-129433, No. 57
-129434, 57-129435, US Patent 4323643
(see issue, etc.). The treatment temperature is usually selected between 18°C and 50°C, but it may also be lower than 18°C or higher than 50°C. It is preferable to use an automatic processor for photographic processing. In the present invention, the total processing time from the time the photosensitive material is put into the automatic processor until it comes out is 60 seconds to 120 seconds.
Even when set to seconds, you can still obtain ultra-high contrast negative gradation photographic characteristics. (E) Example <Example 1> Average particle size 0.25μ containing 97% AgBr, 3% AgI
A silver iodobromide emulsion consisting of cubic crystals was prepared by the double jet method, washed with water in a conventional manner, redissolved, and then chemically sensitized using sodium thiosulfate. After dividing this silver iodobromide emulsion into 17 parts, the compounds of the general formula () of the present invention, (1), (8), (10), (11),
(12), (13), (20) and Comparative Compound (A) were added in the amounts shown in Table 1, and then coated on a polyester film in an amount of 3.7 g of silver per 1 m ² . The film sample thus prepared was subjected to wet exposure, and then developed at 20 DEG C. for 1 to 5 minutes using a developer having the composition shown below. <Developer> Hydroquinone 30g 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone 0.3g Sodium sulfite 75g EDTA・2Na 1.0g Tripotassium phosphate 80g Potassium bromide 2.0g NaOH 13g 5-methylbenzotriazole 0.3 g 1-diethylamino-2,3-dihydroxypropane 17g Add water 1 Adjust to pH 11.5 with potassium hydroxide. The results are shown in Table 1. As is clear from Table 1, compared to Comparative Compound (A), the compound of the present invention has almost the same high contrast photographic properties even when developed at 20°C for 1 minute, and it also lasts for a long time. It can be seen that there is no increase in fog even after development. Furthermore, the change in sensitivity due to changes in development time is extremely small compared to Comparative Compound (A), which indicates that it has high stability against development. In addition, looking at the unexposed areas of each sample after development processing, the sample to which comparative compound (A) was added (No. 2.3)
In comparison with the case where obvious sand fog already occurred after 3 minutes of development time, no sand fog was observed in the samples containing the compound of the present invention (Nos. 4 to 17).

[Table] <Example 2> Next, a part of the film sample obtained in Example 1 was
After heating at 40°C for 30 days, exposure and development (20°C for 3 minutes) were performed in the same manner as in Example 1, and the sensitivity and fog values immediately after coating were compared. The results are shown in the table.

[Table] As is clear from the table, the compounds of the present invention show extremely little change in sensitivity and increase in fog over time of storage. <Example 3> Next, using another part of the film sample obtained in Example 1, a halftone dot quality test was conducted. That is, using a 150-line gray contact screen and a sensimetry exposure wedge,
After each film sample was exposed to light, it was developed for 30 seconds at 38°C using the same developer as before, and the quality of the halftone dots was examined. The results are shown in the table. Halftone quality is visually evaluated on a 5-point scale.
represents the best quality and 1 represents the worst quality. As halftone dot original plates for plate making, grades 5 and 4 are practically usable, grades 3 are poor but barely usable, and grades 2 and 1 are of a quality that is practically unusable.

[Table] As is clear from the table, it can be seen that the compounds of the present invention exhibit good halftone dot quality.

Claims (1)

[Scope of Claims] 1. An image forming method characterized by developing a silver halide photographic material in the presence of a compound represented by the following general formula (). General formula () [Wherein, Ar represents an aryl group, and R represents a hydrogen atom, an alkyl group, an alkenyl group, an unsaturated heterocyclic group, or an aryl group. R ₁ and R ₂ represent a hydrogen atom or a group represented by the general formula (). ] General formula () [In the formula, R ₀ represents an alkyl group, an alkenyl group, an aryl group, an alkoxy group, or an aryloxy group, and n represents an integer of 1 or 2. ]