JPS61145549A - Silver halide photographic sensitive material - Google Patents

Abstract

PURPOSE:To improve the stability of a latent image on a silver halide photographic sensitive material for X-ray photography, especially a direct reversal photosensitive material to aging during the time from the end of exposure to the beginning of development by incorporating a polybasic carboxylic acid into the photosensitive material. CONSTITUTION:An aliphatic higher fatty acid, preferably <=6C fatty acid such as oxalic acid, tartaric acid or maleic acid or an aromatic polycarboxylic acid is incorporated into a silver halide emulsion layer to improve the stability of a latent image to aging during the time from the end of exposure to the beginning of development. A silver halide photographic sensitive material, especially a direct reversal photosensitive material stabilizing a latent image, having continuous gradient and suitable for X-ray photography is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a silver halide photographic material, and more particularly to a silver halide photographic material with improved latent image storage stability.

[Background of the invention and conventional technology]

Conventionally, silver halide photosensitive materials have had poor latent image stability between exposure and development, resulting in undesirable phenomena such as sensitization and desensitization over time until development, as well as fluctuations in the amma value. It has been known.

For example, this is undesirable in the case of medical film, as it leads to a decline in diagnostic ability and an increase in radiation exposure due to re-shooting, and for general use, it is extremely inconvenient, as it eliminates the chance of taking another shot. be.

In addition, particularly in direct reversal silver halide photosensitive materials, a latent image is formed optically or chemically in advance on the silver halide photographic emulsion, and the degree of formation is adjusted so that the maximum density is achieved after development. However, if this is unstable, it will cause a decrease in the maximum concentration and further cause gamma fluctuations.

This is extremely undesirable in terms of photographic performance. Furthermore, in the case of the direct inversion type, the storage time of the latent image IgJ is much longer than in the negative type, and higher stability is required.

As described above, improvement in the stability of latent images is strongly desired in terms of photographic performance.

Many proposals have been made as methods for stabilizing the undesirable development of sensitization or desensitization due to the poor stability of latent images over time from exposure to development of silver halide photographic materials. For example, British Patent No. 1,308.777, British Patent No. 1,378,354, British Patent No. 1°386.130.
No., West German Patent No. 2,335,090, etc., a method using a sulfur-containing amino acid compound, US Pat. No. 3,447,926, British Patent No. 1.224.
Specification No. 685, JP-A-49-14120, JP-A No. 50-
A method using a nitrogen-containing heterocyclic compound described in JP-A No. 94918, etc., a method using a mercapto compound described in JP-A-46-21987, U.S. Patent No. 3,318゜70
There is a method using nitrilotriacetic acid described in the specification of No. 2, a method using a guanazole compound described in JP-A-4S-29835, etc., but the effectiveness decreases significantly during storage before exposure. In addition, there are problems in that the effect of stabilizing the latent image after exposure decreases over time, and in some cases, the solubility in the solvent used when added to the silver halide photographic material is too low.

In addition, one of the important properties of direct reversal silver halide photographic materials is gradation, and in copying photographs with continuous gradation over a relatively large density range, such as X-ray photographs,
It is desired that the gradation is soft, and there is a particular demand for the development of a photosensitive material that can effectively reduce contrast while maintaining a predetermined maximum density.

As a means to meet such requests, U.S. Patent Nos. 3 and 3
No. 64,026 discloses a technique for reducing contrast by incorporating a certain type of sensitizing merocyanine dye. However, there is a problem in that the inclusion of the dye makes fog nuclei more likely to be oxidized, resulting in large fluctuations in maximum density and mass over time6. The development of effective technology for stabilization is desired.

[Purpose of the invention]

An object of the present invention is to provide a 7% silver halide photographic material with improved stability of a latent image over time from exposure to development. The object of the present invention is to provide a direct reversal silver halide photographic material in which the stability of a latent image optically or chemically imparted to a silver halide photographic emulsion is improved.

[Structure of the invention]

An object of the present invention is to provide a silver halide photographic material having a photosensitive layer on a support, at least one of the photosensitive layers.
The layer is achieved by a silver halide photographic material containing at least one polybasic carboxylic acid.

The present invention will be explained in detail below.

The polybasic carboxylic acids used in the present invention include aliphatic carboxylic acids and aromatic carboxylic acids.Aliphatic carboxylic acids may be saturated or unsaturated, and preferably have 6 carbon atoms.
For example, oxalic acid, malonic acid, glutaric acid,
Adipic acid, pimelic acid, speric acid, azelaic acid,
Examples include sebacic acid, tartronic acid, malic acid, tartaric acid, maleic acid, hexamaric acid, citraconic acid, mesaconic acid, itaconic acid, and the like. The aromatic carboxylic acid preferably has 9 or less carbon atoms, such as 7-talic acid, isophthalic acid,
Examples include terephthalic acid and camphoric acid. The number of carboxy groups in the polybasic carboxylic acid may be 2 or more. Particularly preferred polybasic carboxylic acids include oxalic acid, tartaric acid, malonic acid, succinic acid, hexamaric acid, maleic acid, malic acid, and citric acid.

These compounds can be dissolved in a suitable solvent such as water, methanol, ethanol, etc. and added to the constituent elements of the silver halide photographic light-sensitive material by a conventional method. These compounds are preferably added to the silver halide emulsion layer, but if necessary, they may also be added to layers adjacent to the silver halide emulsion layer, such as a protective layer, an intermediate layer, etc., to the extent that it does not affect photographic performance. can do. These compounds can be added to the constituent elements of a silver halide photosensitive material at any time during the manufacturing process, but when added to the silver halide emulsion layer, they may be added after chemical ripening or after coating. It is preferable to add it beforehand. The amount of the compound used at this time depends on the type of compound, type of silver halide, and p of the emulsion.
H, although it varies depending on various factors such as the type and amount of other additives used, it is usually 0.38 to 3.5 g per mole of silver halide, and more preferably 0.6 g.
It is preferable to use the amount in the range of g to 2.0 g.

Silver halide emulsions forming the photosensitive layer of the silver halide photographic light-sensitive material according to the present invention include silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide emulsions, etc. Silver oxide is dispersed in a protective colloid as described below, and these emulsions can be prepared using various methods, such as a neutral method, an ammonia method, and an acid method.
It can be produced by various methods such as the method of incorporating a Group 8 soluble metal salt as described in British Patent No. 3-4125 and British Patent No. 1,186,717.

The silver halide photographic material according to the present invention is for general black and white use,
It may be used for X-ray, micro, printing, electron beam recording, infrared recording, color, direct reversal, etc., but the effects of the present invention are particularly remarkable in direct reversal. .

When the present invention is applied to a direct reversal silver halide photographic light-sensitive material, any suitable method can be used to impart fog to the silver halide emulsion containing a polybasic carboxylic acid, for example, by uniformly printing the entire surface with light. Fogging can be carried out chemically by exposure or by using a suitable reducing agent, such as a compound of a metal which is also electrically positive, as described in British Patent No. 723,019. In order to obtain a direct reversal image with high sensitivity, various methods can be applied, such as the method of applying fog using a combination of a reducing agent and a gold compound, as described in Japanese Patent Publication No. 46-40900.

Typical useful reducing agents include, for example, formalin, hydrazone, polyamines (triethylenetetramine, tetraethylenepentamine, etc.), thiourea oxide, tetra(hydroxymethyl)phosphonium chloride, amineborane borohydride compounds, and primary chloride. tin, tin (I
I) Typical useful metal compounds that are electrically more positive than silver include chloride, etc., and include soluble salts of gold, rhodium, platinum, palladium, iridium, etc., such as potassium chloroaurate. , chloroauric acid, ammonium palladium chloride, sodium iridium chloride, and the like.

The degree of fogging of direct reversal silver halide emulsions can vary over a wide range. The degree of fogging is determined by the silver halide composition and grain size of the silver halide emulsion used, as well as the type and concentration of the fogging agent used, and the time at which fogging is applied, as is well known to those skilled in the art. 98. of emulsion.
It is related to pAg, temperature, time, etc.

The emulsion also contains organic desensitizers that exhibit a strong desensitizing effect when added to ordinary silver halide emulsions as solarization accelerators, such as Binacryp Yellow, Pinacryptol Green, 7E/S7 Lanin. or salts of metals in group 8 of the periodic law, such as rhodium chloride, iridium chloride salts, etc. Depending on the purpose, sensitization with cyanine dyes, pseudocyanine dyes, hemicyanine dyes, uncyanine dyes, etc. It may contain pigments.
1. Ike's photographic additives can also be added to the silver halide emulsion used in the light-sensitive material of the present invention. As a stabilizer, for example, Japanese Patent Publication No. 49-16053, Japanese Patent Publication No. 49-1265
No. 1, those described in JP-A No. 48-66828, etc.
Alternatively, triazoles, azaindenes, quaternary benzothiazolium compounds, mercapto compounds, or water-soluble inorganic salts such as cadmium, cobalt, nickel, manganese, and zinc may be included. Hardeners such as formalin, di-17oxal, aldehydes such as mucochloric acid, S-triazines, epoxies, azidinones, vinylsulfonic acid, etc., and coating aids such as saponin, sodium polyalkylene sulfonate, polymers, etc. .

Lauryl or oleyl monoether of lyethylene glycol, amylated alkyl taurine, JP-A-49-1
Fluorine-containing compounds selected from those listed in Japanese Patent Publications No. 0722, No. 49-46733, etc., and sensitizers such as Japanese Patent Publications No. 42-25203, No. 43-10245, No. 43-13822, No. 43 -17926, 43-
No. 17927, No. 46-21186, No. 49-810
It may also contain polyalkylene oxides and derivatives thereof selected from those described in No. 2, No. 49-8332, and the like.

Furthermore, for example, Japanese Patent Publication No. 45-24910, No. 45-298
It is also possible to contain color couplers selected from those described in No. 78 and the like. In addition, brighteners, thickeners, desensitizers, matting agents, antistatic agents, etc. can also be contained as necessary.

The silver halide emulsion according to the present invention contains protective colloids such as gelatin, gelatin derivatives, and natural substances such as fulpmin, agar, 72-biagum, and aluic acid, as well as polyvinyl alcohol, polyvinyl acrylate, polyvinyl vicritone, and partially hydrated cellulose ether. Hydrophilic polymers such as decomposition cell a-suacef-) and poly(N-hydroxylfurkyl)β-alanine derivatives grafted with ethylene toxide described in Publication I Publication No. 49-20530 can be included. Furthermore, a dispersion-polymerized vinyl compound may also be included as a binder for emulsions. For example,
A polymer latex of an unsaturated ethylenic monomer emulsion polymerized in the presence of an activator as described in Japanese Patent Publication No. 5-55956, and a ceric salt having hydroxyl groups as described in Japanese Patent Publication No. 49-20964. It is possible to contain a polymer latex etc. in which a high molecular compound is grafted with an unsaturated ethylenic monomer.

Also, from the emulsion technology, Japanese Patent Publication No. 44-2523, No. 44
9499, or protect and contain higher fatty acids such as liquid paraffin or higher unsaturated fatty acids such as stearyl acetoglyceride to improve the film properties, and furthermore, depending on the purpose, color couplers, It is also possible to protect and contain stabilizers and the like.

In the photographic material of the present invention, a silver halide emulsion layer,
The other layers may be any suitable photographic support such as glass,
Wood, metal, films such as cellulose acetate, cellulose acetate butyrate, cellulose nitrate, polyester, polyamide, polystyrene, etc., paper,
It is coated on baryta-coated paper, polyolefin-coated paper such as polyethylene or polypropylene-coated paper, and the polyolefin-coated paper can be subjected to electron bombardment treatment to improve the adhesion of the emulsion.

〔Example〕

Example (1) A silver iodobromide emulsion for direct reversal with an average grain size of about 0.5 μm was prepared according to the following recipe.

(iv) [Acetic acid Amount to neutralize to pH 6.0 First, solution (b) was added to solution (a) at 40°C, and while stirring, solution (c) was further added over 3 minutes. After aging at 40° C. for 20 minutes, the solution (2) was enriched and neutralized to pH 6.0. After desalting this emulsion, the pH was adjusted to 6.8 and the pAg was adjusted to 7.5.
Tetraethylenepentamine and potassium chloroaurate were added, and the mixture was aged at 60°C until proper fogging was obtained.

After ripening, the emulsion was divided, exemplified compounds of the present invention and comparative compounds were added as shown in Table 1, coating aids and hardeners were added, and the emulsion was uniformly coated on a polyethylene terephthalate film base and dried. It was used as a sample. The obtained samples were divided into two groups, of which 1. Ifl is 23℃, relative humidity 5
5%, other 1, [1ha50'(:', relative humidity 80%
Each was left for 3 days under these conditions.

These samples were exposed to light using a Sakura D Applicator Model 1 (manufactured by Konishiroku Photo Industry Co., Ltd.) through a wedge, and developed at 35° C. for 30 seconds using a developer having the composition shown below.

Developer composition Anhydrous sodium sulfite 70 g Hydroquinone 1 og Sodium carbonate hydrate 20 g Phenyl-3-pyrazolidone 0.35 g Potassium hydroxide
5g5-methylbenzotriazole
0.05g potassium bromide 5g
Glutaraldehyde bisulfite 15 g water
vinegar acid
Add 8g water to make 19.

Thereafter, fixing, washing with water, and drying were carried out using conventional methods.

The maximum concentration and gamma of the obtained sample were determined. The results are shown in Table-1. In addition, sample No. 2
and No. 3 are samples containing comparative compounds, and No. 4 to 7 are samples containing the polybasic carboxylic acid table of the present invention.
As is clear from Example 1, it can be seen that according to the present invention, a direct reversal silver halide photographic light-sensitive material can be obtained in which there is little decrease in maximum density due to aging after latent image formation and little variation in gamma.

Example (2) A silver iodobromide emulsion layer for direct reversal prepared in the same manner as Example (1) was adjusted to pH 8.0, and then formalin and chloroauric acid were added to obtain proper fog at 60°C. It was matured until. After ripening, the emulsion is divided and the following sensitizing dyes (
After adding 0.15 g 1 mol^gx of merocyanine dye), the polybasic carboxylic acid of the present invention and a comparative compound were added,
Coated and dried. The obtained samples were divided into two groups, one group was immediately exposed and developed in the same manner as in Example (1), and the other group was left at 40°C and 80% relative humidity for 7 days. , exposure and development were performed in the same manner. The maximum concentration and gamma of the obtained sample were determined. The results are shown in Table-2. In addition, samples N009 and No.
, 10 is a sample containing a comparison compound, and No.

Samples Nos. 11 to 14 are samples containing exemplary compounds of the present invention.

Sensitizing dye (merocyanine dye) As is clear from Table 2, even when using a sensitizing dye,
The light-sensitive material according to the present invention has less decrease in maximum density and less variation in gamma.

Example (3) Tested by conventional method! 1! ! After ripening the silver iodobromide emulsion with an average grain size of 1.2μ by adding gold and sulfur compounds,
The polybasic carboxylic acid of the present invention and a comparative compound were added as shown in Table 3, a stabilizer, a coating aid, and a hardening agent were added, and the mixture was uniformly coated on both sides of a polyethylene terephthalate film base and dried. did. These samples were placed between medium-sensitive X-ray fluorescent intensifying screens (manufactured by Tokyo Shibaura Electric Co., Ltd.), passed through an alumina edge, and exposed to a tube voltage of 60 k.
x#i exposure was carried out under the condition of vpw tube current of 200 Ω. Among these samples, one set was immediately prepared, and the other set was left at 40°C and 70% relative humidity for 7 days, and then developed, fixed, washed with water, and dried in the same manner as in Example (1). The sensitivity, gamma and maximum density of the obtained samples were determined and shown in Table 3.

In addition, the sensitivity was measured for a sample to which no compound was added (No. 15).
It is expressed as a relative sensitivity, with the sensitivity of > being 100. (In the table, N
Nos. 0 and 16 are comparative compounds, and Nos. 17 to 21 are samples containing exemplary compounds of the present invention. ) As seen from Table 3, it can be seen that the stability of latent images is significantly improved by the present invention, and fluctuations in sensitivity, amma, and maximum density due to time after latent image formation are reduced.

〔Effect of the invention〕

The stability of the latent image over time after exposure, that is, from the time the latent image is formed until it is developed, is improved, and fluctuations in sensitivity, gamma, maximum density, etc. due to the time after the latent image is formed are reduced. do.

Claims (1)

[Claims] A silver halide photographic material having a photosensitive layer on a support, wherein at least one of the photosensitive layers contains at least one type of polybasic carboxylic acid.