JPS6014337B2 - 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 indispensable for silver halide photographic materials, is decreasing in supply and increasing demand, leading to a significant rise in price.As a result, the industry is actively trying to reduce the amount of silver used. This is the current situation.

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 brightness, 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 image finally obtained is a positive image, it is not suitable for the purpose of the method of the present invention, which is to form a negative image.

On the other hand, according to Tsubaki Publication No. 54-48544, as a photosensitive material for finally obtaining a negative image by a silver salt diffusion transfer method, (1) a photosensitive silver halide layer (U) itself is coated on a support. (1) A structure has been proposed that is more easily portable and includes a combination of a layer in which a solubilizing agent is adsorbed to metal salt particles that are substantially non-photosensitive, and physical development nuclei. .

The method includes processing with a physical developer containing at least one type of reducing agent (specifically, a silver halide developer) and a silver halide dissolving agent (specifically, a sulfite) as a developer, This is to obtain a shadow image. However, in this processing method, the process of precipitating and reducing silver ions on the physical development nuclei takes time, so it lacks suitability for the rapid development process that has been implemented in recent years, and the inertness of the nucleus process is the main reason. As a result, the sensitivity and technical density are insufficient, and as a result, wire saving cannot be achieved. Furthermore, it has many drawbacks, such as the fact that the tone of the resulting negative image is difficult to turn neutral gray, making it unsuitable for use in X-ray photosensitive materials, where image silver is visually evaluated. It turned out that. Therefore, the present inventors proposed Mochito Sho 54-124344 specification (Tokizeki Sho 5
No. 6-47037) proposed a developing solution in which amines are added in combination as a negative image forming method that improves the above-mentioned drawbacks.

However, even this method is not necessarily satisfactory in terms of image tone after development or storage stability of the developer itself, and further improvements have been desired. Therefore, the first aspect of the present invention
The purpose of the above 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; A second object of the present invention is to provide a method for forming low fog, high contrast images more quickly by means of a novel silver halide image enhancement method. A third objective is to provide a novel image forming method that can rapidly obtain fine-grained, neutral gray shade images.

A fourth object is to provide a developer that maintains stable characteristics without any fluctuation in photographic performance even when stored at high temperatures for long periods of time.

Purposes other than these will become clear from the examples described above. As a result of extensive studies, the present inventors have discovered that all of the above objects can be achieved by the novel negative image forming method described below. That is, '1' photosensitive silver halide on a support, '2) particles of a metal salt that is more easily soluble than the photosensitive silver halide and whose surface has been solubilized with an elutriator, and (2) physical particles. After exposing a photosensitive photographic element containing a combination of development nuclei and a developing nucleus, the photosensitive photographic element is treated with an alkaline composition containing a silver halide developer and at least one compound represented by the following general formula. This is a negative image forming method characterized by processing.

- Twin support type R, 1 SfR3kiX・R4na mSnanR2
(R and R2 in the formula are substituted or unsubstituted alkyl groups, aryl groups, and alkenyl groups, respectively, and R3 and R
4 is an alkylene group or an arylene group, and X is one.

Any one of 1-C〇〇1, 1C〇NH1, 1C〇NHC〇, m is 0 or 1, and n is an integer from 0 to 20. ) At least one of RI and R2 is substituted with a hydrophilic group.

Preferred examples of this substituent include a hydroxyl group, a carboxyl group, a sulfonic acid group, and an amino group.
Specific examples of compounds that can be used in the present invention are shown below, but the present invention is not limited thereto.

Compound no. I HOH2C--day2C--S-CH2C
H20H No. 2 days 5C200CH2CH2C
--S-CH2CH20th No. 3 No. 4 No. 5 No. 6 Day 3COOCH2C--S-℃Day 2C
OOCH3No. 7 Nippon XH2CH2C--S-
CH2CH2COOHNo, 8 daypi XH2CH
2C--S-CH2CH2C Pini 2nd 5No. 9
Day 2NOCHNH2CH2C--S, CH2CH2NH
CONH2N〇, l.

H No. 2CH2C-S in 2CH2C-S in 2CH2NH in 2CH2NH 11 (Sun 3C) 2NOCHNH2
CH2C--S-CH2CH2NHCON(CH3)2
No. 12 HOH2CH2C--S-CH2CO
NHCH2NHCOCH2SCH2CH20HNo. 1
3 HOOCH2CH2C--S-CH2CH20C
H2CH2SCH2CH2COOHNo. 14H
OH2CH2C--S-CH2CH2CH2S03Na
No. 15 days 2NH2CH2C--S-CH2C
H2NH2No. 16 HOH2CH2C--S-C
H2--S-CH2CH20HNo. 17 HOH
2CH2C--S--CH2CH2--S-CH2CH
20H No. 18 Na03SH2CH2CH2CS
-CH2CH2SCH2CH2CH2S03NaNo.
19 day M day 2CH2C--S-CH2CH2S
-CH2CH2COOHNo. 20 days 5C20CO
H2CH2C-“S-CH2CH2S-CH2CH20
COC 2nd 5th No. 21 No. 22 No. 23 No. 24 No. 25 n-tei 5 No. 26 ntei 10 As for the synthesis method, it can be synthesized according to known methods such as the reaction of a compound having a mercapto group with a halogen compound or a compound having a double bond. There is a description in .

According to an embodiment of the negative image forming method of the present invention, a negative image with high maximum density and low capri can be quickly obtained by adding the compound of the above general formula to the developer during processing. .

Furthermore, the compound of the present invention can provide rapid processing effects not only in the usual high-temperature development but also in normal temperature development. This is extremely useful in view of recent energy conservation efforts. The compound according to the present invention is more easily soluble than photosensitive silver halide, and has the property of dissolving metal salt particles whose surfaces have been made key-solubilized by a refractory agent during development.

In carrying out the present invention, the compound may be used alone or in combination of two or more in a developer containing a developer, and may also be used in combination with other known silver halide solvents such as sulfite, thiosulfate, etc. It can be used in combination with salt or thiocyanate.

The amount of the compound of the present invention to be used may range from 0.0019 to 50 times per development processing solution, and the most preferred amount is from 0.01 to 10 times per developer. For addition, water or a hydrophilic organic solvent such as methanol or ethylene glycol is used. Note that even when the developer is viscous, it can be used in the same manner as above. below,
Embodiments of the invention will now be described in further detail.

First, the light-sensitive photographic element used in the present invention is as described above.
1' photosensitive silver halide, '2} metal salt particles, and [
Photosensitive silver halides include silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodobromide, and silver iodobromide. Although silver or a mixture thereof is included, it is preferable to use silver iodobromide with high sensitivity, and silver iodobromide containing 50% by mole or less of silver iodide is particularly suitable in the present invention. It is.

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 in a silver halide solvent than the photosensitive silver halide and have substantially no photosensitivity.

In the method of the present invention, the term "substantially not photosensitive" herein means "non-photosensitive" in relation to the photosensitive silver halide; Specifically, it is to be understood that when the light-sensitive photographic element of the present invention is provided with the light energy necessary to sensitize the light-sensitive silver halide, it is "substantially unsensitized" by the light energy. 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 have substantially no photosensitivity. The silver halide grains are silver halide grains that do not have
Grains are selected that have a high rate of dissolution in the substance that dissolves the 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 layer sensitization treatment, and is Crystals of these metal salts are preferably finer than those of silver halide, and particles of these metal salts are preferably used in an amount of 0.1 mol to 50 mol per mol of photosensitive silver halide. 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 rust ions generated by dissolving the metal salt particles are reduced to metal by a reducing agent. 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.

Examples of binders in this case include gelatin, siligasol, polyvinyl alcohol, gum arabic, agar, and cellulose derivatives. Focal Press 1972 King edition (London/New York).

Furthermore, the elutriation agent used in the present invention is selected from compounds that adsorb to halogenated synthetic fiber particles, which are easily soluble metal salt particles, and reduce the solubility of the silver halide particles.

These compounds are, for example, mercapto compounds,
More specifically, representative examples include cysteine, norphenyl-5-captotetrazole, and mercaptobentsiazole. Further, thiourea indazoles, triazoles, imidazoles and the like are also preferred compounds that can be used in the present invention. The amount of the above compound to be used is in the range of 0.01 to 2.0 molar per mole of silver halide. Furthermore, any developer can be used as the developing agent of the developer used in the present invention. For example, hydroquinone, 4-N
-Methylaminophenol (methol), ascorbic acid, isoascorbic acid, 2,6-dimethyl-4-aminophenol, toluhydroquinone, 2,6-dimethylhydroquinone, 2-methyl-4-amino-6-methoxyphenol, 2,6- Dimethoxy 4-aminophenol, 2,5-dimethylhydroquinone, 2,4,6
Examples include monotriaminophenol, 2,4-diaminophenol (amidol), N,N-dimethylhydroxylamine, and 4,6-diamino-ortho-cresol. Further, as alkaline agents, for example, inorganic alkaline agents such as caustic soda and soda carbonate, as well as diethylamine and the like are added to the developing solution.

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. In particular, as a development inhibitor, the specification of Japanese Patent Application No. 54-11193
The imidazole, indazole, and triazole derivatives described in Japanese Patent Publication No. 644) are suitable.

As described above in detail, the present invention utilizes the principle of silver salt diffusion transfer method to eliminate fogging by using a structure of a silver halide compound that has been converted into silver and a physical developer containing a silver halide solvent. It is characterized by the ability to quickly form high-sensitivity negative images with little turbulence.

The inventors have also discovered that the above-mentioned excellent effects can be achieved by the presence of a compound having a structure as shown in the above-mentioned general formula during the above-mentioned negative image forming step.

Furthermore, in the present invention, several embodiments can be considered with respect to the configuration of photosensitivity enhancement, but there are three types: high-sensitivity silver halide, a metal salt having substantially no photosensitivity, such as silver chloride, and physical development nuclei. are contained in the same emulsion layer and coated on the support, or metal salts having substantially no photosensitivity, such as chloride radiation, and physical development nuclei are contained in the same layer on the support. Most preferred is a structure in which an emulsion layer is coated, and an emulsion layer containing high-sensitivity silver halide is further coated 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 (i) Preparation of photosensitive silver halide (highly sensitive lactating agent) Silver iodobromide emulsion (silver iodide 7 After preparing mol %), a second ripening is performed by a gold/sulfur sensitization method, and then 0.00% of 4-hydroxy-6-methyl-1,3, powder, 7-tetrazaindene is added per mol of silver halide as a stabilizer. After 3 days of addition, a highly sensitive silver iodobromide emulsion was obtained.

(ii) Preparation of easily soluble metal salt grains (silver halide emulsion with virtually no photosensitivity) After preparing a pure silver chloride emulsion consisting of silver nitrate and sodium chloride by a normal neutral method, the grains are washed by a precipitation method. An emulsion was prepared by adding 0.6 t of 1-phenyl-5-mercaptotetrazole per mole of silver chloride as a scale-solubilizing agent to the emulsion.

The average particle size of the silver chloride particles was about 0.1 micron. (iii) Preparation of physical development nuclei Physical development nuclei consisting of silver sulfide were prepared in an aqueous gelatin solution with sodium sulfide and silver nitrate.

Next, the physical development nuclei were added to the above-mentioned easily soluble silver chloride emulsion, and then an appropriate amount of saponin was added as a coating aid, and the emulsion was uniformly coated onto a subbed polyester base.

At this time, the amount of silver coated in the silver chloride emulsion was 2.1 m/m, the amount of silver in the physical development nuclei was 0.01 m/m, and the amount of gelatin was 3 m/m. Next, on this layer, an appropriate amount of sodium amber 2-ethylhexyl-ester monosulfonate was added as a coating aid to the photosensitive silver iodide emulsion described above, and the amount of silver was reduced to 2.
．． It was coated uniformly so that the amount of gelatin was 09/Mede and the amount of gelatin was 3/3.

Furthermore, a 2.5% gelatin aqueous solution containing an appropriate amount of a hardening agent (formalin) and a coating aid (same as above) was applied as a protective layer on top of this layer, thereby producing a photosensitive material according to the present invention.

3. The obtained film piece. After wedge exposure with MS light, development was carried out at 35° C. for 3 stages using a developer having the following formulation, followed by fixation, washing with water and drying, followed by sensitometry. [Developer formulation] Hydrokimene 12.0 Polyanhydrous sodium sulfite 65.0 Taufenidone
1.0 potassium hydroxide
15.0% The above developer was used as a standard comparative developer, and the compounds of the general formula according to the present invention were added as shown in Table 1 below, and the results were developed.

Table 1 To make the results easier to understand,
I have attached a drawing, which shows the characteristic curve of the photosensitive material according to the present invention, and 1 in Figure 1 shows the case where only the photosensitive silver iodobromide emulsion according to the present invention is coated in a single layer. With the curve of
2 is a characteristic curve when the lacquerable metal salt (silver chloride) emulsion layer containing physical development nuclei according to the present invention and the photosensitive silver iodobromide emulsion layer of i are coated in a multilayer manner.

3 and 4 in FIG. 2 are compounds related to the present invention, including M.
3 and M. This is a characteristic curve when 2.0 of No. 12 was added per developer per night. As is clear from these figures 1 and 2, the negative image formation rule according to the method of the present invention is that in contrast to 1 when the photosensitive emulsion layer is a single layer, in the multilayer 2 with the silver chloride emulsion layer, It is clear from FIG. 2 that a photographic material with extremely high sensitivity and high gamma can be obtained, and that when the development process according to the method of the present invention is applied, it is possible to form a negative image with further improved characteristics. I can understand what makes it possible. Example 2 An emulsion was prepared by adding physical development nuclei to exactly the same easily soluble chloride emulsion used in Example 1.

A photosensitive silver iodobromide emulsion similar to that used in Example 1 was mixed with this emulsion to prepare a coating solution. The mixing ratio is a dose ratio of silver chloride emulsion and silver iodobromide emulsion of 3:1 molar,
The amount of silver coated was adjusted to 2.0 ta'.
Furthermore, a protective layer similar to that in Example 1 was provided on top of the protective layer to obtain a photosensitive material of the present invention. 3. Same as Example-1 for the obtained film sample. After the next MS wedge exposure, an experiment was conducted by adding the compounds according to the present invention and comparative compounds as shown in Table 2 using the developer shown below as a standard.

Developer Hydroquinone 10 Anhydrous Sodium Sulfite 65 Tough Ednin
1.0 potassium hydroxide
16.0 E5 Nitroindazole
0.3 Potassium polybromide
Add 0.2 t water and leave overnight.

2. As a light-sensitive material, even in the case of the single layer method according to the present invention, by adding the compound of the present invention to the developer, the developability can be improved.

It can also be seen that there is very little deterioration of the characteristics even when the developer is left in a harsh environment. Note that good results can also be obtained when 0.5 ta of sodium thiosulfate is uniformly added to the developer of Example 3 for development.

[Brief explanation of drawings]

FIG. 1 is a characteristic curve diagram of a device other than the present invention, and FIG. 2 is a characteristic curve diagram of an embodiment of the present invention. 1 is a characteristic curve of a photosensitive material consisting of a photosensitive emulsion layer that does not contain physical development nuclei. 2 is a characteristic curve of a photosensitive material consisting of an emulsion layer having physical development nuclei and a photosensitive emulsion layer. Figure 1 Figure 2

Claims (1)

[Scope of Claims] 1. 1. Photosensitive silver halide on a support, 2. Particles of a metal salt that is more easily soluble than the above-mentioned photosensitive silver halide and whose surface has been made difficult to solubilize with a retarding agent, and 3. Physical development. A method for forming negative images, which comprises, after imagewise exposure of a photosensitive photographic element containing nuclei, treating it with an alkaline composition containing at least one halogenated radiation developer and a compound represented by the following general formula. General formula R_1-S-[R_3(X・R_4)-_mS]
-_nR_2 In the formula, R_1 and R_2 are each a substituted or unsubstituted alkyl group, aryl group, or alkenyl group, and at least one of R_1 and R_2 is substituted with a hydrophilic group. R_3 and R_4 are alkylene groups,
is an arylene group, and X is -O-, -COO-, -CON
H-, -CONHCO- group, m
represents 0 or 1, and n represents an integer from 0 to 20.