JP2516052B2 - Silver halide photographic light-sensitive material capable of obtaining high-contrast images - Google Patents

Description

The present invention relates to a silver halide photographic light-sensitive material, and particularly to a silver halide photographic light-sensitive material capable of obtaining a photographic image with high contrast.

[Background of the Invention]

Conventionally, silver halide photographic light-sensitive materials have been widely used in the photomechanical process. This photolithography process step includes the step of converting a continuous tone original into a halftone image, that is, the step of converting the continuous tone density change of the original into a set of halftone dots having an area proportional to this density. Has been.

In this conversion step, a silver halide photographic light-sensitive material having a high contrast photographic property is used to photograph a document through an intersecting screen or a contact screen, and this is developed to form a halftone image. Was doing.

In order to impart a high contrast property to an image, there is a conventional method described in JP-A-56
-106244 and U.S. Pat.No. 4,686,167, a silver halide photographic light-sensitive material contains a compound such as hydrazine as a so-called contrast-increasing agent, and further, the contrast-increasing properties of this compound are effectively exhibited. It has been adjusted so as to obtain a desired photographic light-sensitive material by using silver halide grains or by appropriately combining other photographic additives. The silver halide photographic light-sensitive material thus obtained is certainly stable as a light-sensitive material, and a high-contrast photographic image can be obtained by processing with a developer capable of rapid processing. .

Further, JP-A-63-29751 proposes a high-contrast light-sensitive material using a novel hydrazine derivative, and the contrast has been improved.

However, in such a silver halide photographic light-sensitive material, when a continuous tone original is converted into a halftone dot image, a sandy pin-like fog, that is, a black pin is generated in the halftone dot, and the quality of the halftone dot image is increased. Had the problem of damaging. Therefore, in order to solve this problem, measures such as adding various stabilizers and inhibitors having a hetero atom have been conventionally taken, but it was not always effective.

[Object of the Invention]

The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a silver halide photographic light-sensitive material which has high contrast photographic characteristics and which can suppress fog generated in a halftone dot image and exhibit high-contrast photographic characteristics. .

[Structure of Invention]

The above object of the present invention is a silver halide photographic light-sensitive material having at least one silver halide emulsion layer, which contains a compound represented by the following general formula [I]. Achieved by the material.

[In the formula, R ₁ and R ₂ may be the same as or different from each other and may have a substituent (for example, a phenyl group, a p-methylphenyl group, a p-methoxyphenyl group, p-cyanophenyl group, p-chlorophenyl group, p- (t-amyl) phenyl group, p-acetylphenyl group, o-hydroxymethylphenyl group, o-hydroxyethylphenyl group, p-octylphenyl group, p-
Dodecyloxyphenyl group, m-butoxyphenyl group, etc.).

R ₃ is an aryl group (for example, the groups mentioned for R ₁ and R ₂ ), a heterocycle (for example, pyridyl group, furyl group, thiophenyl group, pyrrole group, etc.), hydrogen atom, alkyl group (methyl group, ethyl group, butyl group) , Octyl group, dodecyl group, etc.).

R ₄ is Or represents OR ₇ , R ₅ , R ₆ and R ₇ are a hydrogen atom, an optionally substituted alkyl group (for example, a methyl group, an ethyl group, a butyl group, a dodecyl group or a propenyl group, an alkenyl group such as a butenyl group, A methoxy group, an ethoxy group, a butoxy group, a methoxymethyl group, a phenyloxy group and the like) and an aryl group (a phenyl group and a substituted phenyl group mentioned for R ₁ and R ₂ ) are represented. The following are typical compounds represented by the above general formula [I]. However, it goes without saying that the specific compounds of the general formula [I] that can be used in the present invention are not limited to these compounds.

The silver halide photographic light-sensitive material of the present invention contains the compound represented by the above general formula [I]. The amount of the compound of the general formula [I] contained in the photographic light-sensitive material of the present invention is It is preferably 5 × 10 ⁻⁷ to 5 × 10 ⁻¹ mol per mol of silver halide contained in the photographic light-sensitive material of the present invention.

Particularly, it is preferably in the range of 5 × 10 ⁻⁵ mol to 1 × 10 ⁻² mol.

The silver halide photographic light-sensitive material of the present invention has at least one silver halide emulsion layer. That is, at least one silver halide emulsion layer may be provided on one side of the support, or at least one layer may be provided on each side of the support. The silver halide emulsion can be coated directly on the support or can be coated through another layer such as a hydrophilic colloid layer containing no silver halide emulsion. A hydrophilic colloid layer as a protective layer may be coated on the emulsion layer. Further, the silver halide emulsion layer may be separately coated on each of the silver halide emulsion layers having different sensitivities, for example, high sensitivity and low sensitivity. In this case, an intermediate layer composed of a hydrophilic colloid may be provided between each silver halide emulsion layer. An intermediate layer may be provided between the silver halide emulsion layer and the protective layer. That is, a non-photosensitive hydrophilic colloid layer such as an intermediate layer, a protective layer, an antihalation layer and a backing layer may be provided if necessary.

In order to incorporate the compound represented by the general formula [I] into the silver halide photographic light-sensitive material of the present invention, it is preferable to incorporate it into the hydrophilic colloid layer in the material, particularly preferably the silver halide emulsion layer and / or Alternatively, it may be contained in a hydrophilic colloid layer adjacent to the silver halide emulsion layer.

However, the compound of the general formula [I] may be contained in another layer instead of the silver halide emulsion layer. For example, it may of course be contained in another hydrophilic colloid layer which is laminated and coated on this emulsion layer.

The most preferred embodiment of the present invention is that the compound of general formula [I] is contained in the silver halide emulsion layer, and the hydrophilic colloid contained in the silver halide emulsion layer and the hydrophilic colloid layer is gelatin or a gelatin derivative. It is a certain silver halide photographic light-sensitive material.

In order to incorporate the compound of the general formula [I] of the present invention into the silver halide emulsion layer and / or the hydrophilic colloid layer, a method of dissolving the compound in appropriate water and an organic solvent and adding it,
Alternatively, a method in which a solution dissolved in an organic solvent is dispersed in a hydrophilic colloid matrix such as gelatin or a gelatin derivative and then added, or a method in which it is dispersed and added in latex is added. The present invention may use any of these methods.

When added, the compound of the above general formula [I] is
Even when used alone, preferable image characteristics can be obtained.
Further, even if two or more kinds of these compounds are used in combination at an appropriate ratio, they do not adversely affect the image characteristics.

As one preferred embodiment of the present invention, the compound of the general formula [I] according to the present invention may be added to the silver halide emulsion layer. In another preferred embodiment of the present invention, it is added to a hydrophilic colloid layer directly adjacent to a hydrophilic colloid layer containing a silver halide emulsion layer, or to an adjacent hydrophilic colloid layer via an intermediate layer.

As another addition method, the compound of the above general formula [I] is dissolved in a suitable organic solvent, for example, water, alcohols such as methanol and ethanol, ethers, esters, etc. The silver halide photographic light-sensitive material may be incorporated in the silver halide photographic light-sensitive material by coating it directly on the outermost layer of the silver halide emulsion layer.

Next, the silver halide used in the silver halide photographic light-sensitive material of the present invention will be described. The silver halide having any composition can be used. Examples are silver chloride, silver chlorobromide, silver chloroiodobromide, pure silver bromide and silver chloroiodobromide.
The average grain size of the silver halide grains is preferably in the range of 0.05 to 0.5 .mu.m, among which 0.10 to 0.40.
It is preferable that the thickness is μm.

The grain size distribution of the silver halide grains used in the present invention is arbitrary, but the monodispersity value defined below is preferably from 1 to 30, and more preferably from 5 to 20.

The monodispersity is 10 divided by the standard deviation of the particle size divided by the average particle size.
It is defined as a value multiplied by 0. The grain size of silver halide grains is represented by the edge length of cubic grains for convenience.

When the present invention is carried out, for example, as a grain of silver halide, a grain having a multi-layered laminated structure of at least two layers can be used. For example, the core portion is silver chloride, the shell portion is silver bromide, On the contrary, it is possible to use silver chlorobromide grains in which the core portion is silver bromide and the shell portion is silver chloride. At this time, iodine can be contained in any layer, but iodine is preferably within 5 mol%.

When preparing the silver halide emulsion of the present invention, a rhodium salt can be added to control the sensitivity or gradation. The addition of the rhodium salt is generally preferred during grain formation, but may be during chemical ripening or preparation of the emulsion coating solution.

The rhodium salt used in the present invention may be a simple salt or a double salt. Typically, rhodium chloride, rhodium trichloride, rhodium ammonium chloride and the like are used.

The amount of rhodium salt added can be freely changed according to the required sensitivity and gradation, but it is from 10 ^-9 mol to 10 ^-4 mol per 1 mol of silver.
A molar range is useful.

When the rhodium salt is used, other inorganic compounds such as iridium salt, thallium salt, cobalt salt and gold salt may be used together. Iridium salts can often be preferably used in the range of 10 ⁻⁹ to 10 ⁻⁴ mol per mol of silver for the purpose of imparting high illuminance characteristics.

The silver halide used in the present invention can be sensitized with various chemical sensitizers.

Examples of the sensitizer include active gelatin, sulfur sensitizer (sodium thiosulfate, allylthiocarbamide, thiourea,
Allyl isothiocyanate, etc., Selenium sensitizer (N, N-
Dimethyl selenoureas, selenoureas, etc.), reduction sensitizers (triethylenetetramine, stannous chloride, etc.), such as potassium chloroaurite, potassium aurithiocyanate, potassium chloroaurate, 2-aurothio-3-
Various noble metal sensitizers represented by methylbenzothiazolium chloride, ammonium chloroparadate, potassium chloroplatinate, sodium chloroparadite and the like can be used alone or in combination of two or more. When a gold sensitizer is used, rodan ammon can be used as an auxiliary agent.

The present invention is preferably applied when surface latent image type grains are contained as silver halide grains. Here, the surface latent image type particles mean particles prepared so that the sensitivity when treated with a surface developing solution in the art is higher than the sensitivity when treated with an internal developing solution.

The silver halide emulsion used in the present invention is a mercapto compound (1-phenyl-5-mercaptotetrazole,
2-mercaptobenzthiazole), benzotriazoles (5-bromobentriazole, 5-methylbenzotriazole), benzimidazoles (6-nitrobenzimidazole, etc. can be used for stabilization or fogging suppression. A sensitizing dye, a plasticizer, an antistatic agent, a surfactant, a hardener and the like can be added to the silver halide emulsion used in the present invention.

Gelatin is suitable as the binder of the compound of general formula [I] according to the present invention for the hydrophilic colloid layer, but hydrophilic colloids other than gelatin can also be used.

Examples of the support used in the present invention include Paraita paper,
Polyethylene coated paper, polypropylene synthetic paper, glass plate, cellulose acetate, cellulose nitrate,
For example, polyester films such as polyethylene terephthalate, polyamide films, polypropylene films, polycarbonate films, polystyrene films and the like are included as typical ones. These supports are appropriately selected depending on the intended use of the silver halide photographic light-sensitive material.

To develop the silver halide photographic light-sensitive material of the present invention, the following developing agents are used.

Typical examples of the HOCH = CHn OH type developing agent include hydroquinone, and catechol and pyrogallol.

Further, as the HOCH = CHn NH ₂ type developer, ortho and para aminophenols or aminopyrazolones are typical ones, and 4-aminophenol and 2-amino-
6-phenylphenol, 2-amino-4-chloro-6
-Phenylphenol, 4-amino-2-phenylphenol, 3,4-diaminophenol, 3-methyl-4,6-
Diaminophenol, 2,4-diaminoresorcinol,
2,4,6-triaminophenol, N-methyl-p-aminophenol, N-β-hydroxyethyl-p-aminophenol, p-hydroxyphenylaminoacetic acid, 2-
Aminonaphthol and the like.

Heterocyclic developers include 1-phenyl-3-pyrazolidone, 1-phenyl-4,4-dimethyl-3-pyrazolidone, 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone and 1-phenyl. -4-methyl-
4-hydroxymethyl-3-pyrazolidone and the like can be mentioned.

In addition, The James of TH Theory of the Photographic Process 4th Edition (The Theory of
the Photographic Process, Fourth Edition) No. 291-33
Page 4 and the Journal of the American Chemical Soc
Society, Vol. 73, page 3,100 (1951) and the like can be effectively used for the silver halide photographic light-sensitive material of the present invention.

These developers may be used alone or in combination of two or more kinds, but it is preferable to use two or more kinds in combination. The effect of the present invention is not impaired even if a sulfite such as potassium sulfite or ammonium sulfite is used as a preservative in the developer used for processing the light-sensitive material of the present invention.

Further, hydroxylamine or a hydrazide compound may be used as a preservative. Others: Adjusting pH with a caustic alkali, alkali carbonate, amine, etc. as used in general black and white developers, and providing a buffer function, and inorganic development inhibitors such as bromcali and organic development inhibitors such as benzotriazole, ethylenediaminetetraacetic acid, etc. Metal ion scavenger, development accelerator such as methanol, ethanol, benzyl alcohol, polyalkylene oxide, sodium alkylaryl sulfonate, natural saponin,
It is optional to add a surfactant such as a saccharide or an alkyl ester of the above compound, a hardening agent such as glutaraldehyde, formalin and gluoxal, and an ionic strength adjusting agent such as sodium sulfate.

The developer used in the present invention may contain alkanolamines or glycols as an organic solvent.

〔Example〕

Examples of the present invention will be described below. As a matter of course, the present invention is not limited to the following examples.

Example-1 An exemplary compound represented by the general formula [I] and a comparative compound (the types of which are shown in Table 1 below) were added to a silver halide emulsion layer of a photographic light-sensitive material in the following manner. , A sample was prepared.

[Preparation of silver halide photographic light-sensitive material]

On one undercoat layer of polyethylene terephthalate film of 100 μm thickness with 0.1 μm undercoat layer on both sides,
The silver halide emulsion layer of the following formulation (1) has a gelatin content of 1.
5g / m ² and silver amount of 3.3g / m ² are coated, and a protective layer of the following formulation (2) is further coated thereon so that the amount of gelatin is 1.0g / m ² , Also, on the other undercoat layer on the other side, a backing layer containing 3.5 g of gelatin was prepared according to the following prescription (3).
It is coated so that it will be / m ² and the following prescription (4) on it
The protective layer of N was coated so that the amount of gelatin would be 1 g / m ² , and Sample N
o.1 to 13 were obtained.

Formulation (1) [Silver Halide Emulsion Layer Composition] Gelatin 1.5 g / m ² Silver chlorobromide (AgCl 60 mol%, AgBr 40 mol%, monodispersity = 12, containing Rh and Ir 10 ⁻⁶ mol / Ag 1 mol) 3.3 g / m ² antifoggant: 4-hydroxy-6-methyl-1,3,3a, 7-
Tetrazaindene 0.30 g / m ² Compound of the present invention or comparative compound: according to Table-1 Surfactant: Saponin 0.1 g / m ² Latex polymer: Polyethyl acrylate-acrylic acid copolymer 1 g / m ² Sensitizing dye: Structure Four types of formulas (A) to (D) were used in combination.

Development modifier: nonylphenoxy polyethylene glycol 10 mg / m ² 5-methylbenzotriazole 7 mg / m ² adenine 3 mg / m ² guanine 2 mg / m ² uracil 2 mg / m ² adenosine 2 mg / m ² 1-phenyl-5-mercaptotetrazole 3 mg / m ² hydroquinone 100 mg / m ² phenidone 10 mg / m ² formulation (2) [emulsion protective layer composition] gelatin 1.0 g / m ² matting agent: an average particle size of 3.0~5.0μm polymethylmethacrylate 0.05 g / m ² surfactant Agent: Sodium n-dodecylbenzenesulfonate 0.01g / m ² Charge modifier: C ₈ F ₁₇ COONH ₄ 10mg / m ₂ NaCl 100mg / m ² LiCl 30mg / m ² Stabilizer: 1-Phenyl-5-mercaptotetrazole 3 mg / m ² Hardener: Formalin 0.03 g / m ² Formulation (3) [Backing layer composition] Gelatin 3.5 g / m ² Dye: Surfactant: Saponin 0.1 g / m ² Hardener: glyoxal 0.1 g / m ² Formulation (4) [Backing protective layer composition] Gelatin 1 g / m ² Matting agent: Polymethyl methacrylate with an average particle diameter of 3.0～5.0Myuemu 0.5 g / m ² Surfactant: sodium p-dodecylbenzenesulfonate 0.01 g / m ² Development modifiers: 5-nitroindazole 0.012 m / g ² 5-methyl-benzotriazole 0.02 g / m ² 1-phenyl-5-mercaptotetrazole 0.005 g / m ² Hardener: Formalin 0.03 g / m ² obtained sample For this, a halftone dot quality test was performed by the following method.

(Test method for halftone dot quality) A stepped wedge is partially attached with a return halftone screen (150 lines / inch) having a halftone dot area of 50%, a sample is brought into close contact with the step wedge and exposed for 5 seconds with a xenon light source. Develop the sample with the following developing solution and the following fixing solution in an automatic processor for rapid processing under the following conditions, and set the halftone quality of the sample to 100
Observed with a double magnifying glass, the one with high halftone dot quality is ranked as "5", and the following 5 "4", "3", "2", "1"
It was ranked. Note that the ranks "1" and "2" are levels that are not practically preferable.

Fog in halftone dots was also evaluated in the same manner, and those with no black pins in halftone dots were given the highest rank of "5" and rank "4" according to the degree of occurrence of black pins in halftone dots. ",
The ranks of “3”, “2”, and “1” were sequentially lowered and evaluated. Incidentally, in the ranks "1" and "2", the black pin is also large, which is a level unfavorable for practical use.

(Developer formulation) (Composition A) Pure water (ion-exchanged water) 150 ml Ethylenediaminetetraacetic acid disodium salt 2 g Diethylene glycol 50 g Phosphoric acid 10 g Potassium sulfite (55% w / v aqueous solution) 100 ml Potassium carbonate 50 g Hydroquinone 15 g 5-Methylbenzotriazole 200mg 1-Phenyl-5-mercaptotetrazole 30mg Potassium hydroxide Amount to adjust the pH of the working solution to 11.5 Sodium bromide 3g (Composition B) Pure water (ion exchanged water) 3ml Diethylene glycol 50g 3-Diethylamino-1,2-propanediol 15g Ethylenediaminetetraacetic acid disodium salt 25mg Acetic acid (90% aqueous solution) 0.3ml 5-Nitroindazole 110mg 2-Mercaptobenzimidazole-5-sodium sulfonate 30mg 1-Phenyl-3-pyrazolidone 500mg N-methyl-p-aminophenol 25mg When using the developer in 500 ml of water Serial composition A, was dissolved in the order of composition B, it was used finish 1.

(Fixing solution formulation) (Composition A) Ammonium thiosulfate (72.5% w / v aqueous solution) 240 ml Sodium sulfite 17 g Sodium acetate trihydrate 6.5 g Boric acid 6 g Sodium citrate dihydrate 2 g Acetic acid (90% w / w aqueous solution) 13.6ml (Composition B) Pure water (ion exchanged water) 17ml Sulfuric acid (50% w / w aqueous solution) 4.7g Aluminum sulphate (Al ₂ O ₃ equivalent content is 8.1% w / w aqueous solution) 26.5g Use of fixer At times, the above composition A and composition B were dissolved in 500 ml of water in this order, and the solution was finished to 1 before use. The pH of this fixer was about 4.3.

(Development processing conditions) (Process) (Temperature) (Time) Development 40 ° C 15 seconds Fixing 35 ° C 15 seconds Washing at room temperature 20 seconds As the comparative compound added to the silver halide emulsion layer in Formula (1), the following ( The compounds a) to (c) were used.

(Test Results) Table 1 shows the compounds added to the silver halide emulsion layers and the addition amounts thereof for Samples Nos. 1 to 10 of the present invention and Samples Nos. 11 to 13 prepared using the comparative compound. Indicated. The compounds of general formula [I] in Table 1 are shown by the numbers of the exemplified compounds.

Table 2 shows the results of the halftone dot quality test, ranked for each of the above samples.

As is clear from Table-2, regarding the dot quality,
Samples Nos. 1 to 10 according to the present invention all showed a result of rank "4" or higher and rank "5" or more, and comparative sample No. 11
All of ~ 13 show results of rank "3".
If the ranks "1" and "2" are considered to be levels that cannot be put to practical use, it is hard to say that Sample Nos. 16 to 18 have good halftone dot quality, but Sample No. according to the present invention. It was found that all of .1 to 10 were excellent in that the dot quality was extremely high.

Regarding the occurrence of black pins as an index of fog, Sample Nos. 1 to 10 according to the present invention are all rank "5".
Or, it was evaluated to be “4” and showed extremely good results without fog, while Comparative Samples 11 to 13 were all ranked “2” or less and showed results that were not suitable for practical use. .

Example-2 In the sample No. 7 of the example-1, the monodispersion degree (uniformity of grain size) of the silver halide grains was changed to 4 to 40, and the sample No. 1 was used.
4-18 were created and experimented.

In addition, 8 × 10 ⁻⁷ mol / Ag 1 mol of rhodium and 3 × 10 ⁻⁷ mol / Ag 1 mol of iridium were added according to a conventional method when the particles were prepared. The silver halide composition here is 98 mol% of silver chloride.
Sensitizing dye ((a), (b),
Instead of adding (c) and (d), a desensitizing dye having the following structure was added.

Desensitizing dye (the sum of polarographic anode and cathode potentials is positive) Furthermore, in the protective layer, 50 mg / m ² of the following filter dye was added, In addition, 100 mg / m ^{2 of the following} ultraviolet absorbing dye was added.

 Others are the same as the sample No. 7, for example, the general formula
The same exemplified compound No. 14 as the compound represented by [I]
Using. Singletness is the pH potential of the charged particles, Ag ion
By changing the supply amount of
Method control Preparation by double jet method
Can be.

Further, exposure and development were also carried out in the same manner as in Example-1 to evaluate photographic performance.

However, in this example, for the exposure of the prepared sample, an ultra-high pressure mercury lamp was used and irradiation was performed with energy of 5 mJ.

The evaluation results are shown in Table-3. Samples No.14 to No.18 are all good with halftone dot quality of 4.5 to 5 and black pins 4.5 to 5,
It was found that the halftone dot quality was high and the fog was extremely small.

[Effects of the Invention] According to the present invention as described above, by incorporating the compound represented by the general formula [I] into the silver halide photographic light-sensitive material, it has the high contrast property of a photographic image and is excellent in high halftone dot quality. It is possible to obtain a photosensitive material.

Claims (1)

(57) [Claims] 1. A silver halide photographic light-sensitive material having at least one silver halide emulsion layer, which contains a compound represented by the following general formula [I]. [In the formula, R ₁ and R ₂ may be the same or different from each other and represent an aryl group which may have a substituent.
R ₃ represents a group selected from an aryl group, a heterocycle, a hydrogen atom and an alkyl group. R ₄ is Alternatively, it represents OR ₇ , and R ₅ , R ₆ and R ₇ represent a hydrogen atom, an optionally substituted alkyl group and an aryl group. ]