JPS6014335B2 - Shadow image forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel negative image forming method, more specifically, it utilizes photosensitive silver halide, metal salts, and physical development nuclei to achieve high sensitivity, high contrast, and maximum density image formation. The present invention relates to a novel image forming method for obtaining a high shadow image.

Silver, which is essential for silver halide photographic materials, is decreasing in supply and increasing demand, which has caused the price to rise dramatically.As a result, the industry is trying to reduce the amount of silver used. Currently, this is actively being done.

For example, one example is a silver salt diffusion transfer method using physical development nuclei.

This method has a very high covering power (silver covering power) of the transferred image, so a higher density photographic image can be obtained with a small amount of silver halide, and it also has excellent sensitivity and sharpness, making it extremely useful. This is known as an image forming method. However, this method is a negative/positive type diffusion transfer method, and since the final image obtained is a positive image, it is not suitable for the purpose of the method of the present invention to form a negative image.

On the other hand, according to Tokuseki Akihiro-48 Pay No. 4, as a photosensitive material for finally obtaining a negative image by a silver salt diffusion transfer method, (i) a photosensitive silver halide layer and (ii) a photosensitive silver halide layer and (ii) It has been proposed that (i) a combination layer comprising a layer in which an elutriator is adsorbed to particles of a metal salt which is more easily soluble and has substantially no photosensitivity and physical development nuclei is provided; As a matter of course, the solubility of silver halide adsorbed with a solubilizing agent is significantly reduced.

Therefore, when a photosensitive material including the silver halide layer is processed with a processing solution containing at least a reducing agent and a substance that dissolves the solubilized silver halide, the process of causing the silver halide to precipitate on the physical development nuclei is difficult. , which is extremely time consuming and requires a long development process. Therefore, it is not possible to perform the rapid processing that has been desired in recent years. Furthermore, the efficiency of this process is extremely low, resulting in loss of sensitivity and density, and it is inevitably impossible to reduce the amount of silver. Furthermore, adding an elutriation agent to a light-sensitive material in an amount that makes easily soluble silver halide grains difficult to melt causes various drawbacks such as desensitization of the light-sensitive material during long-term storage. have. Therefore, the inventors of the present invention
-45719 (see Tsubaki Seki No. 55-137528), as a new negative image forming method that improves the above-mentioned drawbacks, the above-mentioned easily soluble metal salt particles whose surfaces have been scale-solubilized in advance with a solubilizing agent are described. Instead of using a breaker, which is a refractory agent, by coexisting with untreated metal salt particles, or by adding an elutriator to the processing solution, the development process can be speeded up and a further improved quality can be obtained. It was disclosed that images can be obtained.

However, it has been found that the method described in Hakama Akisho No. 54-45719 still has the drawback that the obtained image is accompanied by fog.

Therefore, the first object of the present invention is to provide a novel silver halide photographic material capable of producing negative images with high sensitivity, high contrast, and high maximum density in a silver-saving light-sensitive photographic element. It is a further object of the present invention to provide a method for forming relatively low fog and high contrast images by means of a novel silver halide image enhancement method.

Therefore, as a result of various studies and examinations by the inventors of the present invention, it was found that (ii) photosensitive silver halide, (i) which is more easily soluble than the photosensitive silver halide, and which is substantially photosensitive. A photosensitive photographic element containing a combination of particles of a metal salt whose surface is elutriated with a refractory agent and (iii) physical development nuclei is prepared by dissolving at least the reducing agent and the particles of the metal salt. The particles of the metal salt in the exposed area are selectively dissolved by treatment with a processing solution containing a substance and a substance that elutriates at least the metal salt in the presence of a specific fog suppressant, and then physical development is performed. It has been found that this object is achieved by a novel negative imaging method which comprises the step of depositing a metallic image on the nucleus.

That is, according to the image forming method of the present invention, by including a fog-inhibiting compound of the following general formula in the developing solution, a negative image with high maximum density and low fog can be formed without impairing the contrast. can be caused to form. In the general formula [this], X, Y, and Z each represent an N atom or a CR group (R is a hydrogen atom, a lower alkyl group, or an aryl group); Alkoxy group, aryloxy group, NO group, N
02 group, CN group, halogen atom, COR group, S02R
4 group, hydroxyl group, aryl group, or (respectively) a hydrogen atom, a lower alkoxy group, an OH group, a lower alkyl group, an aryl group, an aryloxy group, R5, R6
represent a water atom, a lower alkyl group, or an aryl group, respectively.

) Hereinafter, specific representative examples of the antifogging compound according to the present invention will be described, but the present invention is not limited thereto.

The capri-inhibiting compound represented by the above general formula is
The amount used is in the range of 0.019 to 10 days per day of development processing solution, and the solvent used for addition is water or a hydrophilic organic solvent such as methanol.

Hereinafter, embodiments of the present invention will be described in more detail.

First, the photosensitive photographic element used in the present invention is as described above (i
) photosensitive silver halide, (ii) metal salt particles, and (
lii) It contains a rough combination of physical development nuclei, but photosensitive silver halides include silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodobromide, silver chloroiodobromide, or these. Although silver iodobromide having high sensitivity is preferably used, silver iodobromide containing 50 mol % or less of silver iodide is particularly suitable in the present invention.

Further, the photographic emulsion containing silver halide used in the present invention is prepared by a conventional manufacturing method. Further, the silver halide grains used in the present invention include those having various crystal habits.

This silver halide emulsion can be sensitized using various sensitizers, and can also be spectrally sensitized using a sensitizing dye to impart photosensitivity to a desired spectral region. It can be stabilized using various stabilizers.

Next, the metal salt particles used in the present invention are metal salts that have a higher dissolution rate with respect to the dissolving substance described below than the photosensitive silver halide and have substantially no photosensitivity.

In the method of the present invention, the term ``substantially not having photosensitivity'' refers to the above-mentioned photosensitivity. "Non-light-sensitive" in relation to silver halide, and specifically means that the light-sensitive photographic element of the present invention is provided with the light energy necessary to sensitize the light-sensitive silver halide. It should be understood that when applied, the light energy is "substantially unsensitized." As a result of the dissolution of the metal salt particles, the metal ions or metal rust ions generated are reduced to metal on the physical development nuclei in the presence of a reducing agent. The metal salt particles used in the present invention may be appropriately selected from those having the above-mentioned properties, but in a preferred embodiment of the present invention, the metal salt particles are substantially photosensitive. The silver halide grains are selected from grains having a higher dissolution rate in a substance that dissolves the silver halide grains than the photosensitive silver halide grains.

More specifically, the metal salt particles preferably applied to the present invention are pure silver bromide, pure silver chloride, or a mixed silver halide thereof that has not been subjected to chemical sensitization treatment, It is desirable that the crystals be finer than that of
It is desirable that the material be solubilized in advance with an elutriation agent.
These metal salt particles are preferably used in an amount of 0.1 to 10 mol per mol of photosensitive silver halide. The above-mentioned elutriation agent is selected from so-called stabilizers, such as Research Disclosure RD-9232 (December 1971), R
An example is shown in D-17643 (197 Yoo December).

Among these, the most preferred key solubilizing agent for the present invention is 1-phenyl-5-mercaptotetrazole, and the phenyl group may have a substituent. These refractory agents are preferably used in an amount of 0.01 to 2.0 per mole of halogenated wire.
Used in the evening range.

Furthermore, the physical development nucleus according to the present invention is a substance having a function of catalytically promoting the process in which metal ions or metal ions produced by dissolving the metal salt particles are reduced to metal by a reducing agent, or It includes chemically active points that have this function.

Specific examples thereof include metal colloids dispersed in a binder, metal sulfide colloids, and other metal salt colloids.

Binders in this case include gelatin, siligasol, polyvinyl alcohol, gum arabic, agar, cellulose derivatives, etc.As for the method of preparing physical development nuclei, for example, - Described in Karpeles 1972 King's edition (London/New York).

Further, the substance that dissolves the readily soluble metal salt particles used in the present invention is a substance that acts on the metal salt particles to generate metal ions or soluble metal complex ions. Sulfites such as sodium sulfite; thiosulfates such as sodium thiosulfate and ammonium thiosulfate; cyanates such as potassium cyanide; thiocyanates such as sodium thiocyanide; thiocyanates such as rhodanammon; amino acid compounds such as cystine and cysteine;
Thiourea compounds such as 3,6-di-thia 1,8-octadiol and the like can be mentioned. Furthermore, the solubilizing agent used in the present invention is selected from compounds that adsorb to silver halide grains, which are easily soluble metal salt particles, and reduce the solubility of the silver halide grains. These compounds are, for example, mercapto compounds, and more specifically include cysteine, 1-phenyl-5-mercaptotetrazole, mercaptobenchiazole, etc. as typical examples. In addition, thiourea indazole,
Triazoles, imitazoles, etc. are also preferred compounds that can be used in the present invention. The amount of the substance to be added to dissolve the metal salt is preferably 10 to 1.0 times/day, and particularly preferably 50 to 500 times/day per treatment solution. Finally, any developer can be used as the developing agent of the developer used in the present invention. Examples include hydroquinone, 4-N-methylaminophenol (methol), ascorbic acid, isoascorbic acid, 2,6-dimethyl-4-aminophenol, toluhydroquinone, 2,6-dimethylhydroquinone,
-methyl-4-amino-6-methoxyphenol, 2,
6-dimethoxy-4-aminophenol, 2,5-dimethylhydroquinone, 2,4,6-triaminophenol, 2,4-diaminophenol (amidol), N,
Examples include N-diethylhydroxylamine and 4,6-diamino-ortho-cresol. Further, as alkaline agents, for example, inorganic alkaline agents such as caustic soda and soda carbonate, and organic amines such as diethylamine are added to the developer.

In addition, commonly used additives such as a development inhibitor, a color toning agent, a curing agent, and a development accelerator can be added to the developer as required. As detailed above,
The present invention utilizes the principle of the silver salt diffusion transfer method, and achieves rapid processing by using a silver-saving silver halide composition as described in the claims and the use of a developing treatment solution containing a refractory agent. The present invention is characterized in that the occurrence of incidental fog in the negative image forming process can be effectively improved in the presence of the specific compound represented by the above general formula.

The inventors have also discovered that the above effects can be achieved only by the presence of a compound having the structure represented by the above general formula during the negative image forming step.

In addition, in the present invention, several embodiments are conceivable regarding the structure of the photosensitive layer. An emulsion containing metal salts having substantially no photosensitivity, such as silver chloride, and physical development nuclei on the support, in the same layer. The most preferred method is to coat a layer and then coat an emulsion layer containing a highly sensitive silver halide thereon. Hereinafter, the present invention will be explained in more detail with reference to typical examples, but the technical scope of the present invention is not limited in any way by the following examples, and various embodiments are possible. .

Example-1 (Preparation of easily soluble metal salt) Loo0 in which 60% silver nitrate and 30% gelatin were dissolved
A silver chloride gelatin emulsion was prepared by adding 200 g of an aqueous solution containing 24.8 g of sodium chloride to an aqueous solution of 200 g.

This emulsion was then washed by a conventional precipitation method and then redispersed in an aqueous solution containing 400 g of gelatin grains, and the average grain size of the silver chloride crystals was 0.1 micron. (Preparation of high-sensitivity silver halide emulsion) A silver iodobromide emulsion containing 7 mol % of silver iodide prepared from silver nitrate, sodium bromide, and sodium iodide by the usual ammonia method is gold-hyposensitized using the usual method. 4 so that the ratio of stone paper sensitized by the method to gelatin was 1:1.
-Hydroxy-6-methyl-1,3,$,7-tetrazaindene was dispersed in an aqueous solution to prepare a high-sensitivity silver iodobromide emulsion.

Next, on the undercoated polyester base, a physical development nucleus colloid prepared by mixing sodium sulfide, silver nitrate, and zinc acetate with the silver chloride emulsion prepared as described above and dispersing it in an aqueous gelatin solution was added, and sabonin was added as a spreading agent. The silver chloride emulsion was coated at a silver content of 30 evening/final, and the physical development nucleus was coated at a dose of 0.01 evening/final. Sodium 2-ethylhexyl succinate monosulfonate was added to the silver emulsion as a spreading agent to give a silver content of 3.0 μm/g.
3. A photosensitive material is prepared in which a gelatin layer is coated so that the gelatin layer is coated in such a manner that the gelatin layer is coated as a hardening agent, and formalin and glyoxal are added as a hardening agent on top of the protective layer. After exposure to light from the MS, development was performed at 35° C. for seconds using the following developer, followed by fixing, washing with water, and drying.

[Developer prescription]

Conclusion of the above, sub 3.3f/,. A negative image with high brightness was obtained.

On the other hand, Table 1 shows the results of processing by adding 9.2 x 10-4 mol/Z of various inhibitors as shown in the table below to the above developer. Table 1 As is clear from Table 1, the development processing method using the processing solution containing the compound of the present invention has a high rate of reduction in fog density for the light-sensitive photographic material having the structure of the present invention, and moreover, the reduction in maximum density is lower. It can be seen that this is an excellent method with a low rate.

Example 2 For the silver chloride emulsion prepared in Example 1, 60 parts of silver nitrate and 100 parts of potassium iodide were mixed with 9 and 1-phenyl-5.
2. A photosensitive material was prepared in the same manner as in Example 1, except that the pure silver chloride emulsion in Example 1 was replaced with one containing mercaptotetrazole 250 cape.3. D
m loss x x 3.23, Dminl. 10 negative images were obtained, and 0.4 t of compounds of the present invention 6 and 8 and 2,5-dimercapto 1,3,4-thiadiazole as a comparative compound were each added to the developing solution per 00 release of the developing solution. The results obtained are shown in Table 2.

[Developer prescription]

Table 2 As is clear from the examples, when a negative image is obtained by the method according to the present invention, the fog suppressant for suppressing capri in the image has limited selectivity, and the compound of the present invention has limited selectivity. Excellent effects are achieved when combined with other methods.

Claims (1)

[Scope of Claims] 1. On the support, (1) a photosensitive silver halide, (2) a metal salt that is more easily soluble than the photosensitive silver halide and has substantially no photosensitivity is coated on the surface of the support. A photosensitive photographic element comprising a combination of particles rendered hardly soluble by a solubilizing agent and (3) physical development nuclei is treated with at least a reducing agent and (2) the physical development nuclei.
) A method for forming a negative image by processing with a processing solution containing a substance that dissolves metal salt particles, characterized in that the processing is carried out by containing a compound represented by the following general formula in the processing solution. A method for forming a negative image. General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ [Here, X, Y, and Z are each an N atom or a CR group (
R represents a hydrogen atom, a lower alkyl group, an aryl group), and R_1 and R_2 each represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, an aryloxy group, an NO group,
NO_2 group, CN group, halogen atom, COR_3 group, S
O_2R_4 groups, OH groups, aryl groups, or ▲mathematical formulas, chemical formulas, tables, etc. (atom, lower alkyl group, aryl group). ]