JPH0311455B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to photographic developing compositions, and particularly to developing solutions suitable for obtaining high contrast images. It is desirable that photographic images needed in the field of graphic arts have only the highest and lowest density areas and no intermediate density areas (so-called fringes). Therefore, in order to create such photographic images, a combination of a high-contrast silver halide photographic material (hereinafter referred to as a "photosensitive material") and a Lith developer for infectiously developing the material are often used. For information on methods of forming such photographic images and Lith developer, see G.A.C.
Journal of the Franklin Institute
239, p. 221 (1945). A lithium developer in which development occurs contagiously in this way is also called a contagious developer. In recent years, in the printing field, the complexity of printed matter,
With the development of scanners, there is a need to improve the efficiency of the turning process. In response to this demand, improvements have been made in terms of equipment such as printers and in light-sensitive materials. Silver halide photosensitive materials with a sensitivity of 10 ^-5 to 10 ^-4 have been developed. However, these photosensitive materials have a soft tone, so when halftones (halftone dots) and characters are overlapped and exposed as a returned original, the reproducibility of the characters may be poor or the sensitivity to the printer light source may be low. However, there is a need for further improvement. As a method of reducing the photosensitivity of photosensitive materials, inorganic desensitizers such as cupric chloride, rhodium chloride, and iridium chloride, and organic desensitizers such as pinacryptol yellow and phenosafranine are used in the silver halide emulsion layer. method with high silver chloride content (90 mol%
Above) Means using photosensitive silver halide are generally known. However, these conventionally known means have the disadvantage of increasing contamination with silver sludge. The Lith developer for producing high-contrast images has a small concentration of sulfite ion as an air antioxidant, usually less than 0.1 mol/l, and is therefore extremely susceptible to air oxidation and unstable, making it very inconvenient to handle. In order to overcome this drawback, various antioxidants have been investigated, but all have been insufficient. For example, Japanese Patent Publication No. 55-49298 describes a developer containing an increased amount of sulfite for such a purpose, but these have a lot of fringing, low gamma, and are still unsatisfactory in halftone dot quality. On the other hand, when the pH of the developer is increased, fogging is more likely to occur, film properties are deteriorated, and silver sludge is more likely to occur. Silver sludge inhibitors usually tend to deteriorate halftone dot quality, and the conditions under which they are used are important. Although there is a strong demand for shortening the development time of Lith developer, due to the above-mentioned drawbacks, the development time is usually short, at most about 1 minute to 40 seconds. The present invention has been made to improve these drawbacks, and a first object of the present invention is to provide a developing composition that can be stably and rapidly processed. A second object of the present invention is to provide a developing composition that is resistant to air oxidation. A third object of the present invention is to provide a developer composition that has high gamma and gives good halftone quality. A fourth object of the present invention is to provide a developing composition with low fog density and high activity. A fifth object of the present invention is to provide a developing composition with high activity and low silver sludge. The above object of the present invention is to prepare a silver halide containing at least 90 mol % of silver chloride on a transparent support, and to add a water-soluble rhodium salt at 10 ^-5 per mol of silver halide at the time of preparing a silver halide emulsion. A photographic developing composition for a silver halide photographic light-sensitive material having a light-sensitive silver halide emulsion layer containing silver halide prepared in the presence of ~10 ^-3 mol, comprising a p-dihydroxybenzene-based developing agent, the following general formula〔〕
A compound represented by the following general formula [], a sulfite ion concentration of 0.3 mol/l or more,
This is achieved by a photographic developing composition containing a polyalkylene oxide compound and an organic solvent and having a PH value of 11.5 or more. General formula () [In the formula, R ₁ is a nitro group at the 5- or 6-position,
_R2 represents a hydrogen atom or a _C1 to _C5 lower alkyl group. M represents a cation such as a hydrogen atom, an alkali metal atom, an alkaline earth metal atom, or an ammonium ion. ] General formula [ ] [In the formula, Z represents a heterocycle containing a nitrogen atom.
M represents the same meaning as in the general formula []. ] In the general formula [], the heterocycle represented by Z is preferably 5-6 to which a benzene ring may be fused.
membered heterocycle, such as oxazole, benzoxazole, thiazole, benzothiazole,
Examples include rings such as triazine, pyrimidine, tetrazaindolizine, triazaindene, and brine. Further, the heterocycle may have a substituent other than the -SM group described in the general formula [], and examples of the substituent include a halogen atom, a sulfo group, a hydroxyl group,
Examples include lower alkyl groups and phenyl groups. Compounds represented by the general formula [] used in the present invention (hereinafter referred to as compounds of the present invention [])
Examples include 5-nitroindazole, 6-nitroindazole, or alkali metal salts thereof, and these may be used alone or in combination. The concentration range of the compound [ ] of the present invention is 1 mg to 1 g, preferably 10 mg to 300 mg per developer.
mg. A density outside this range is unfavorable in terms of manufacturing cost and photographic performance. The compound [ ] of the present invention may be added after being dissolved in an organic solvent, or may be added directly, and is not limited to its form. Examples of the organic solvent include triethylene glycol, diethylene glycol, diethanolamine, triethanolamine, methanol, and ethanol. The developing agent used in the present invention can be appropriately selected from p-dihydroxybenzene-based developing agents well known in the field of photography. To give a specific example,
Hydroquinone, chlorohydroquinone, bromohydroquinone, isopropylhydroquinone,
toluhydroquinone, methylhydroquinone, 2,3
-dichlorohydroquinone, 2,5-dimethylhydroquinone, hydroquinone sulfonate, etc. Among these, hydroquinone is particularly practical. These developing agents may be used alone or in combination. The amount of the developing agent added is 5 to 50 g, preferably 10 to 30 g per developer. The sulfite used in the present invention may be any salt as long as it liberates sulfite ions (SO ₃ ^2- ) in the developer, and examples thereof include sodium sulfite, potassium sulfite, potassium bisulfite, and the like. The concentration range may be 0.3 mol or more per developer, but 1 mol or more is not practical for production. The preferred amount added is 0.4 mol/~0.7 mol/. If the amount is less than 0.3 mol/mol, the performance changes significantly with respect to air oxidation, making it impractical. In the present invention, the PH range is 11.5 to 13.5,
If it exceeds 13.5, it is dangerous to handle and there is no particular benefit. If it is less than 11.5, it is unfavorable in terms of photographic performance. To adjust the pH, alkalis commonly used in the field of photography, such as sodium hydroxide, potassium hydroxide, potassium carbonate, and sodium carbonate, are used. Next, the polyalkylene oxide compound used in the present invention refers to a compound containing at least 10 or more and at most 200 or less polyalkylene oxide chains in the molecule, such as polyalkylene oxide and aliphatic alcohols, phenols, fatty acids, etc. By a condensation reaction with a compound having an active hydrogen atom such as an aliphatic mercaptan or an organic amine, or by condensing an aliphatic mercaptan, an organic amine, ethylene oxide, propylene oxide, etc. with a polyol such as polypropylene glycol or polyoxytetramethylene polymer. can be synthesized by The above polyalkylene oxide compound has 1 polyalkylene oxide chain in the molecule.
It may be a block copolymer that is divided into two or more parts instead of individual parts. At this time, the total polymerization degree of the polyalkylene oxide is preferably 10 or more and 100 or less. Specific examples of the polyalkylene oxide compounds used in the present invention are shown below.
It is not limited to these.

【table】

【table】 \

( _CH2CH2O ) _{o H}

The amount of polyalkylene oxide compound used in the present invention is 0.01g to 40g per developer.
and preferably 0.1 g to 5 g. The addition method may be by using a solution dissolved in water or an organic solvent such as triethylene glycol or diethylene glycol, or by direct addition. Organic solvents used in the present invention include diethylene glycol, triethylene glycol, tetraethylene glycol, triethanolamine, diethanolamine, and the like. The amount added is 10 g or more, preferably 20 to 100 g per developer. It is not economical to use more than 200g. Specific examples of the compound represented by the general formula [] used in a preferred embodiment of the present invention are shown below, but the invention is not limited thereto. The amount of the compound represented by the general formula [] to be added is 5 mg to 1 g, preferably 10 mg to 500 mg per developer.
mg. The mechanism of the present invention is that the conventional developer causes the first dissociation of hydroquinone (the acid dissociation constant is approximately
10 ^-9.9 )

In contrast, in the developing composition of the present invention, the second dissociation (acid dissociation constant is approximately
10 ^-11.5 )

[Formula] is used, so it is estimated that the pH will be effective in the range of 11.5 to 13.5. In this PH range, the developing agent is very active, usually causes fogging, becomes soft in tone, tends to generate silver sludge, has very poor storage stability over time, and is completely impractical. However, according to the present invention, this high
When a compound having a sulfite ion concentration of at least 0.3 mol per developer in the pH range and a compound represented by the general formula [], a polyalkylene oxide compound, and an organic solvent are used together, fogging can be suppressed extremely effectively and high contrast can be achieved. It was possible to maintain stable and high activity with less silver sludge. Although the theoretical elucidation of this mechanism is not complete, the stabilizing effects of high concentrations of sulfite ions and organic solvents (these effects are not thought to be the same), and the effects of sulfite ions and compounds represented by the general formula [] dissociated form of

This is presumed to be due to a complex synergistic effect such as the interaction between [Formula] and the polyalkylene oxide compound. Furthermore, according to the present invention, silver sludge could be significantly reduced by using the compound represented by the general formula [] in combination. In addition to the above-mentioned compounds, the developer of the present invention includes an auxiliary developer such as 1-phenyl-3-pyrazolidone to an extent that does not inhibit the contrast enhancement effect, a water-soluble acid such as acetic acid or boric acid, potassium carbonate or borax. PH such as
Buffer, potassium bromide, 5-methylbenztriazole, 5-nitrobenzimidazole or 4-
fog suppressants such as hydroxy-6-methyl-1,3,3a,7-tetrazaindene, water softeners such as ethylenediaminetetraacetate or nitriloacetic acid, antioxidants such as ascorbic acid, ethylene urea or kojic acid; It can contain development accelerators such as quaternary ammonium salts, nucleic acid decomposition products such as adenine and guanine, and the like. It is preferable not to contain formalin-generated products such as formalin-bisulfite adducts contained in the Lith developer. As the silver halide used in the silver halide emulsion of the photographic light-sensitive material processed with the developer of the present invention, silver chloride, silver chlorobromide, silver chloroiodobromide, and silver chloroiodide are used. Even in this case, silver halide contains 90 mol% or more of silver chloride. In a preferred embodiment of the present invention, water-soluble rhodium salts used in light-sensitive materials include, for example, rhodium dichloride, rhodium trichloride, ammonium hexachlorodate, etc., but preferably rhodium trichloride and halogen are preferred. A complex compound with chlorine or bromine is preferable. The amount added is 10 ^-5 to 10 ^-3 mol per mol of silver halide, but
More preferably 10 ⁻⁴ to 10 ⁻³ mol. If the amount of the water-soluble rhodium salt exceeds 10 ^-3 , although there is still a tendency to desensitize, the object of the present invention cannot be achieved because the tone becomes soft. On the other hand, if it is less than 10 ^-5 mol, the sensitivity required for use in a bright room, which is one of the objectives of the present invention, cannot be lowered, and the objective cannot be achieved. The emulsion used in the present invention can be prepared by any of forward mixing, back mixing, semi-back mixing, and simultaneous mixing, but the most preferred method is the simultaneous mixing method. In addition, methods for preparing emulsions include the ammonia method,
Preferably, the neutral method or the acidic method is used. The distribution of silver halide grains in the emulsion may be either monodisperse or heterodisperse, but monodisperse is preferable for uniform grain sensitivity. Further, the grain crystal habit may be cubic, octahedral, dodecahedral, spherical, or any other shape. As particle size
The thickness is preferably 1μ or less, preferably 0.5μ or less. More preferably, it is 0.3μ or less. This is because it is necessary to make the developed silver particles finer in order to prevent them from becoming rough and to achieve the required photographic density with a small amount of silver in order to save resources. The emulsion thus prepared can also be chemically sensitized (for example, sulfur sensitization, gold-sulfur sensitization, reduction sensitization, etc.) using a chemical sensitizer. However, chemical sensitization may not be performed at all. Furthermore, the emulsion thus prepared may contain stabilizers such as tetrazaindenes, antifoggants such as triazoles and tetrazoles, covering power improvers, and irradiation inhibitors such as oxanol dyes, dialkylaminobenzylidene dyes, etc. It is possible to add wetting agents, latexes, polyalkylene oxides, and other additives used in general photographic emulsions, such as spreading agents and hardening agents. In the photographic light-sensitive material to which the developing composition of the present invention can be applied, the silver halide photographic emulsion is coated on a support, and the support may be a commonly used transparent film such as a polyester base, glass, or the like. A transparent support is used. EXAMPLES The present invention will be described in more detail below with reference to Examples. The technical scope of the present invention is not limited in any way by the following examples, and various embodiments are possible. Example 1 In an aqueous gelatin solution kept at 50°C, an average particle size of 0.2μ was obtained by a conventional method in the presence of 10 ^-4 mol of rhodium chloride per mol of silver halide from an aqueous solution of sodium chloride and potassium bromide and an aqueous silver nitrate solution. silver chloride 98
A silver chlorobromide gelatin emulsion was prepared in which the balance was silver bromide. After sulfur sensitization of this emulsion according to a conventional method, 6-methyl-4-hydroxy-1,
3,3a,7-tetrazaindene, 1-phenyl-5-mercaptotetrazole, dispersion of polyethyl acrylate, tartrazine, sabonin and hardener, 2-hydroxy-4,6-dichloro-
After adding 1,3,5-S-triazine sodium salt, it was coated on a film base to a silver content of 3 g/m ² and dried. The sample obtained in this way was
HMW-215) through a light wedge, processed with the following developer, and evaluated for return characteristics. (Developer A) Hydroquinone 25g Potassium sulfate 70g Potassium carbonate 35g Ethylenediaminetetraacetic acid-2Na salt 1g Potassium bromide 3g Boric acid 2g Add water to make 1. The pH of the above developer A was adjusted with sodium hydroxide to prepare developers (1) to (10) as shown in Table 1 below, and developed on the same day and after 5 days at 30°C for 20 seconds. The results are shown in Table 2 (same day) and Table 3 (5 days after aging), respectively. The developing solution was left in a rectangular parallelepiped stainless steel container with a depth of 1 m at room temperature. In the table, the halftone dot quality refers to the quality of the return halftone dot.
Visually judge with a 100x magnifying glass and rank from 1 to 10 (10
is the best). Sensitivity was expressed as relative sensitivity.
Gamma is the tanθ value of the straight part of the photographic characteristic curve.
Fog is indicated including film base density.
The silver sludge was evaluated by dividing the amount of silver sludge generated by processing 2 m ² of the film sample without exposure using developer 1 into 10 ranks (10 being the best).

【table】

【table】

【table】

[Table] From Table-2 and Table-3, developers (5) to (8) of the present invention
can be developed quickly in 20 seconds, has stable sensitivity over time, has high gamma and high halftone dot quality, does not cause fogging, and has a good silver sludge. Example 2 Silver halide grains having a silver chloride composition of 98 mol% silver chlorobromide and an average grain size of 0.17μ were produced by a neutral method.
After adding chloroauric acid and hypo and chemically aging at 50°C for 50 minutes, 6-methyl-4-hydroxy-1,
3,3a,7-tetrazaindene was added, and further a dispersion of polymethyl acrylate, exemplary compound [2-5], sabonin, the following compound [A], and 2-hydroxy-4 as a thickener and hardening agent were added. ,6-dichloro-1,3,5-S-triazine sodium salt was added thereto, and then coated on a film base to give a silver content of 2.5 g/m ² and dried. The sample thus obtained was exposed to light using a bright room printer in the same manner as in Example 1, treated with the following developer, and the return characteristics were evaluated. (Developer B) Hydroquinone 22g Potassium sulfate 80g Potassium carbonate 20g Ethylenediaminetetraacetic acid-2Na salt 1g Potassium bromide 2g Add water to make 1. The pH of developer B was adjusted with potassium hydroxide to prepare developer solutions (1) to (18) shown in Table 4 below, and developed on the same day and on the 5th day at 35°C for 20 seconds. It is shown in Table-5 and Table-6. However, the amounts added in the table are per developer.

【table】

【table】

【table】

【table】

[Table] From Table-5 and Table-6, the developer of the present invention (5),
It is clear that (6), (8), (9), (10), (12) and (18) are excellent in various photographic performances. Comparative Example 1 Silver halide grains of silver chlorobromide with a silver chloride composition of 75 mol % and an average grain size of 0.17 μm were prepared by a neutral method, chloroauric acid and hypo were added, and the grains were chemically aged at 50° C. for 50 minutes. Thereafter, Sample A was prepared by adding additives in the same manner as in Example 2, and exposed in the same manner. This sample A was treated with the developer (10) in Table 4 above, and its reversal characteristics were evaluated. On the other hand, silver bromide particles with an average particle size of 0.17 μm were prepared by a neutral method, chloroauric acid and hypo were added, and the particles were chemically aged at 50° C. for 50 minutes. Thereafter, Sample B was prepared by adding the same additives as in Example 2, and exposed in the same manner. This sample B was treated with the developer (10) in Table 4 above, and its return characteristics were evaluated. Table 7 shows the same day results corresponding to Table 5 above.
Table 8 shows the results after 5 days corresponding to Table 6 above. In addition, the developer (10) in Table-5 and Table-6
The processing results are also listed.

【table】

[Table] From Tables 7 and 8, when the silver chloride content is outside the scope of the present invention, such as 75 mol% (sample A) and 0 mol% (sample B), low gamma and halftone quality deterioration are observed. It can be seen that not only that, but also that the amount of silver sludge increases. Comparative Example 2 In the treatment with developer (10) in Example 2, the following comparative compound (-100) was added in the same amount (100
An experiment was conducted with the only difference being the use of a developer (19) containing 1.0 mg/). Comparative compound (-100) The same day results corresponding to Table 5 above are shown in Table 9.
Table 10 shows the results after 5 days corresponding to Table 6 above. In addition, the developer (10) in Table-5 and Table-6
The processing results are also listed.

【table】

[Table] Tables 9 and 10 show that the compound represented by the general formula () of the present invention has low gamma and halftone dots in combination with a comparative compound other than the compound represented by the general formula (). It can be seen that the quality has deteriorated.

Claims (1)

[Claims] 1. On a transparent support, a silver halide containing at least 90 mol% or more of silver chloride is formed, and a water-soluble rhodium salt is added at a rate of 10 ^-5 per mol of silver halide at the time of preparing a silver halide emulsion. A photographic developing composition for a silver halide photographic light-sensitive material having a light-sensitive silver halide emulsion layer containing silver halide prepared in the presence of ~10 ^-3 mol, comprising a p-dihydroxybenzene-based developing agent, the following general A compound represented by the formula [],
Compound represented by the following general formula [], 0.3 mol/
Contains sulfite ion concentration, polyalkylene oxide compound and organic solvent, and has a pH value of 11.5.
A photographic developing composition characterized by the above. General formula () [In the formula, R ₁ is a nitro group at the 5- or 6-position,
_R2 represents a hydrogen atom or a _C1 to _C5 lower alkyl group. M represents a cation such as a hydrogen atom, an alkali metal atom, an alkaline earth metal atom, or an ammonium ion. ] General formula [ ] [In the formula, Z represents a heterocycle containing a nitrogen atom. M
represents the same meaning as in the general formula []. ] 2. Claim 1, wherein the silver halide photographic light-sensitive material contains a polyalkylene oxide compound in the light-sensitive silver halide emulsion layer.
The photographic developing composition described in .