JPS6356653A - Negative image forming method - Google Patents

Abstract

PURPOSE:To increase the density of an image formed by a negative type diffusion transfer process as well as to inhibit the fogging of the image by using a developing soln. contg. a specified hydroquinone deriv. CONSTITUTION:A photosensitive photographic element contg. photosensitive silver halide, nonphotosensitive metal salt particles, a compd. which releases a dissolving agent for the particles or a dissolution and physical development accelerating agent and physical developing nuclei is imagewise exposed and developed with a developing soln. contg. a hydroquinone deriv. having >=-200mV oxidation half-wave potential to a satd. calomel electrode at 13.0pH, e.g., a compd. represented by the formula. By the development, the metal salt particles in the exposed part are selectively deposited on the physical developing nuclei as a metal image. Thus, a negative image having high maximum density, little fog, high sensitivity and a low silver content is obtd. in a short processing time.

Description

Detailed Description of the Invention (A) Technical Field The present invention relates to a negative image forming method for forming a negative image by a novel negative plastic diffusion transfer method, and particularly relates to a negative image forming method with high image density and suppressed capri. .

CB) Prior art and its problems Metallic silver, which is essential as a raw material for silver salt photosensitive materials, has come to be widely used not only in the photographic industry but also in various industries in recent years, and its demand has been increasing. Since it is something that can only be produced naturally, it is thought that there will be a limit to its supply in the future. Due to this situation and the fact that silver bodies are high-value surface metals, attempts have been made to reduce the amount of silver used in silver halide photosensitive materials. A silver salt diffusion transfer method (DTR method) using dissolution physical development is known. The DTR method has the advantage of being able to obtain high-density photographic images with a low amount of silver because the transferred image has a high coverage sig power, and has excellent graininess.However, ordinary DTR.

The image obtained by this method is only a positive image and cannot be used directly in a negative image forming method. An example of a negative image forming method improved to obtain a diffusion transfer image in a negative shop by applying the principle of this diffusion transfer method is the photosensitive silver halide film disclosed in JP-A No. 58-48544. There is a method of causing dissolution physical development in the image area by utilizing the effect of iodine ions released during development. However, in this method, the dissolving power of iodine ions, which act as a silver halide solvent in the image area, is low, so long-term development is required for image formation, and it is difficult to achieve sufficient dissolution physical development. ,
This method has drawbacks such as the need to increase the content of iodine ions contained in silver halide, which limits the emulsions that can be used in practice.

Therefore, the inventors of the present invention have developed an excellent negative image that can be used in a short period of time, has good silver transfer efficiency, can obtain maximum density and high contrast with a low amount of silver, and has no restrictions on the photosensitive silver halide used. The formation method is as follows: 1) Photosensitive silver halide particles 2) Substantially non-photosensitive metal salt particles 3) React with the main development system oxidant produced by development to form the particles of 2) above. A compound that releases a compound that acts as a dissolving agent or dissolving physical development accelerator for non-photosensitive metal salt particles (5olve
nt Releasing Redox Compoun
ds, hereinafter abbreviated as SR, R, compound) <4> A substance containing physical development nuclei has been announced (Japanese Patent Application Laid-Open No. 1524-1983).
No. 7). This negative-tone sensitive material contains a silver halide reducing agent (cross oxidizing agent or electron transfer agent = Elect) whose oxidized form is relatively stable and can oxidize the SRR compound mentioned above in 3).
It is called ron Transfer Agent.

By treating the exposed area with a processing solution containing ETA (hereinafter abbreviated as ETA), the photosensitive silver halide described in item (1) above is developed in the exposed area. By the action of metal ions or metal complex ions generated from ETA and ETA, the metal is precipitated on the physical development nuclei of 4> to obtain an image.

Although these various methods have the five advantages mentioned above,
The developing agent when the metal salt particles in (2) are reduced to metal through dissolution physical development on the physical development nucleus of (4) also depends only on the added ETA, so it is not a normal positive type. Compared to the case of the diffusion transfer method, the developing power is weaker and the amount of developed silver that is precipitated is not sufficient, and as a result, a sufficient maximum density cannot often be obtained in a short processing time.

Furthermore, in this method, development occurs in a layered manner, so even a small amount of oxidized ETA may be generated in the system due to a small amount of capri of the added photosensitive silver halide or air oxidation. This has the disadvantage that dissolution physical development is triggered even in unexposed areas, and as a result, the latitude with respect to development time is narrow.

(C) Object of the Invention The object of the present invention is to provide a negative image forming method capable of obtaining a negative image with high maximum density, suppressed capri, high sensitivity, and low silver content in a short processing time.

(D) Structure of the Invention The present invention consists of (1) photosensitive silver halide (2) on a support;
Metal salt particles that have substantially no photosensitivity (3) A compound that reacts with the main development system oxidant produced by development and acts as a dissolving agent or a dissolved physical development accelerator for the metal salt particles mentioned in (2) above. A light-sensitive photographic element containing a combination of a compound to be released and (4) physical development nuclei is imagewise exposed and then developed to selectively remove the metal salt particles of (2) above in the exposed area. In a negative image forming method comprising the step of depositing a metal image on physical development nuclei of
When the processing solution used in the above development process has a pH of 13.0, the saturated calomel is 1! 120 for Ya (hereinafter abbreviated as 8CE)
Oxidation half-wave potential of 0 mV or more (hereinafter E”/2 (Ox-
) A method for forming a negative image, characterized in that it contains a hydroquinone derivative CI) having the following:

Examples of the compound [CI] used in the present invention include hydroquinone derivatives having moderate electron-withdrawing substituents, but preferably those having one or two electron-withdrawing groups that are diffusible under alkaline conditions. (iIit-converted hydroquinone derivatives are used.

Specific examples of the compound [I] include the following compounds, but the present invention is not limited thereto.

H H These [I] compounds (
Since it has a sufficiently high oxidation potential compared to the 8RR compound and ETA in (3), it does not interfere with the redox reaction between the compound in (3) and ETA, but it also has weak reducing properties, so it cannot be added to the processing solution. By doing so, it prevents air oxidation of the processing solution, acts as an auxiliary developer, and contributes to dissolution physical development.

From the above, the compound CI) can be added as much as it can be dissolved in the processing solution, but it is preferable to add it in a minimum amount of 1t7t to 30s to obtain a sufficient effect.
Used within the range of

Moreover, these compounds may be used alone, or two
You may use it in combination of more than one kind.

The photosensitive silver halide (1) used in the present invention includes silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloroiodide, silver iodobromide, silver chloroiodobromide, or any of these. Although a mixture of these and the like may be used, preferably silver bromide having high sensitivity or silver iodobromide containing 10 molt or less of silver iodide is suitable for the present invention.

Further, the photographic emulsion containing silver halide 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, it can also be spectrally sensitized using a sensitizing dye to impart photosensitivity to a desired spectrum region, and it can also be spectral sensitized using various sensitizing dyes. It can also be stabilized using a stabilizing agent.

The non-photosensitive metal salt particles (2) used in the present invention are (
3) as a dissolving agent for metal salt particles released by the compound.

It is a metal salt which has a higher dissolution rate than the photosensitive silver halide of (1) above and has substantially no photosensitivity. In the present invention, "substantially not having photosensitivity" means not being photosensitized relative to the photosensitive silver halide in (1) above, and specifically, It means that when the light energy necessary to sensitize the light-sensitive silver halide of (2)) is applied to the light-sensitive photographic element according to the present invention, it is not substantially sensitized at that light energy. . In the present invention, the term "non-photosensitive" is also used synonymously.

The non-photosensitive metal salt particles (2) used in the present invention may be selected from those having the above-mentioned properties, but in a preferred embodiment of the present invention, the non-photosensitive metal salt particles (2) are substantially photosensitive. These silver halide grains have a higher dissolution rate in a dissolving agent than the photosensitive silver halide grains described in (1) above. .

More specifically, the metal salt particles preferably applied to the present invention are pure silver chloride particles that have not been subjected to chemical sensitization treatment or chlorobromide particles that have been subjected to desensitization treatment and that contain silver bromide of 25 mole or less. Silver, silver chloroiodide containing 1 mole or less of silver iodide, or mixed silver halide thereof, preferably the photosensitive silver halide of (1) above also has fine crystals,
These metal salt particles are (1) photosensitive silver halide 1
It is used in a range of 0.1 mol to 100 mol, preferably in a range of 1 mol to 10 mol.

The compound (3) that releases a solubilizing agent or a dissolved physical development accelerator (SRR compound) used in the present invention means a compound represented by the following general formula [■].

A-BCII) A redox mother nucleus having the function of total release is present, and B is a substituent that forms a compound that acts to dissolve polymetal salt particles or promote dissolution physical development upon elimination from A. A ballast group may be included to immobilize the person in the photographic element.

Here, one preferably uses a negative-acting dye-releasing redox compound (Diffusible Dye Releases), which is commonly known in the color diffusion transfer process.
ingRedox Compounds, hereinafter referred to as DRR
, abbreviated as compound) is used.

Representative examples are shown below.

No. 4,053,312 U8.3,928.
312 US, 4,055,428 US
, 4,336,322 K described Ba1list Described in JP-A-53-3,819 Described in JP-A-51-IQ 4,343? Described in JP-A-51-104,343 Ba1last Described in JP-A-51-104,343 H3O2- Described in Research Disclosure Magazine, No. 17.465 Described in US, 3,725,062 H H Oxidation as above All reduced cores are 8R used in the present invention.
It can be used as a redox mother nucleus for R compounds.

In the present invention, Ba1list is preferably a group containing a hydrophobic group having 8 to 50 carbon atoms.

The mechanism of B residue release upon development is the same as the mechanism of dye release of the D-R compound in the color diffusion transfer method.
ew, Chem, Int, Ed, Bngl,
It is described in detail in reviews such as Vol. 22, pp. 191-209 (1983) or Organic Synthetic Chemistry, Vol. 39, No. 4, pp. 331-344 (1981).

As the B residue, a substituent that forms a compound that exhibits a metal salt particle dissolving action or a dissolution physical development promoting action, which is known in the field of photographic Pt and optical materials, is usually used.
More preferably, the DRR is a heterocyclic compound such as a substituted uracil, a substituted hydantoin, a substituted imidazolidinethione, a substituted thiazolidinethione, or a substituted oxazolidinethione, which is bonded to the redox nucleus of the compound via a sulfonamide group, as well as a chain-like compound. Compounds conventionally known as silver halide solvents or silver halide dissolution physical development accelerators in the field of silver salt photographic materials, such as substituted thioethers and substituted amino alcohols, are used.

The following are used as examples of the SRR compound [■].

[:II) -1 [11) -2 CI’l　-4 [:n) -6 (-II'']-8.

Cm)-9 These compounds may be used alone or in combination. Furthermore, when Cm) is used as a dissolving agent or a dissolved physical development accelerator-releasing compound, [I[
) may be used as long as it forms an oxidant capable of cross-oxidizing the redox nucleus A of -There are pyrazolidinone derivatives. The developing agent may be contained in the processing solution or in the photosensitive material.

The physical development nucleus (4) in the present invention catalytically promotes the reaction in which metal ions or metal complex ions produced by dissolving the metal salt particles (2) are reduced to metal by a reducing agent. Indicates a substance that has a function. For example, metal sulfide colloids, noble metal colloids, etc. are used, and more specifically, palladium sulfide, nickel sulfide, silver sulfide, metal silver colloids, metal palladium colloids, etc. are preferably used.

The photographic light-sensitive element according to the present invention is basically formed by at least one support and the above-mentioned (1) photosensitive silver halide, (2) metal salt particles having substantially no photosensitivity, and (3) development. It contains a combination of (2) a compound that reacts with an oxidized developing agent and releases a compound that acts as a dissolving agent or dissolved physical development accelerator for metal salt particles, and (4) physical development nuclei. But (1), <2), (3
) and (4) may be contained in a single layer, or a layer containing two or more of them in any combination may be included. In addition, various configurations can be obtained for the order of the skin, including (1), (2), (
3) and (4) may be separately contained on a plurality of supports in any combination and layer configuration, and may be used in combination.

In addition, the photographic element of the present invention may have appropriate eyebrows, such as a protective layer, an intermediate layer, an anti-halation layer, or a backing layer, at various positions depending on the purpose without impairing the effects of the present invention. Alternatively, it may be in a so-called actepator form, which includes a layer containing a developing agent.

Further, in the photographic element of the present invention, depending on the purpose, photographic additives other than those described above may be added to any layer of the photographic element to the extent that the effects of the present invention are not impaired. For example, hardeners commonly used in the art can be used to strengthen adhesion to the support and physical properties of the film, and surfactants can also be used to improve the stability of the coating solution.

Next, any support can be used in the present invention as long as it has a hydrophilic surface. For example, baryta paper that has been subjected to corona discharge treatment, subbing treatment, etc.
Examples include polyethylene-coated paper, cellulose acetate, polyester film of polyethylene terephthalate, polyamide film, polystyrene film, glass plate, or metal plate such as anodized aluminum plate.

Further, the surface hydrophilic treatment methods such as the corona discharge treatment, undercoating treatment, anodizing treatment, etc. can be carried out using known methods commonly practiced in the art.

The present invention will be explained in more detail below using representative examples, but the technical scope of the present invention is not limited thereby.

Example 1 [a] Preparation method of high-sensitivity silver iodobromide emulsion (r(1) Preparation of photosensitive silver halide) Iodination was carried out using silver nitrate, potassium bromide, and potassium iodide by an ordinary neutral method. A silver bromide emulsion (silver iodide 2 mol %) was prepared, chemically sensitized by gold-sulfur sensitization method, and 4-hydroxy-6-methyl-1,3,3a, 7 was added as a stabilizer.
- Citrazaindene was added to obtain a silver iodobromide emulsion with a grain size of 0.4 microns.

[b) Preparation method of desensitized silver chlorobromide emulsion (r(2) Preparation of non-photosensitive metal salt particles) Desensitized salt odor using rhodium chloride as a desensitizer to silver nitrate, sodium chloride, and potassium bromide Silver bromide emulsion (silver bromide 1
2 mol%) was prepared. The grain size of the obtained emulsion grains is 0.
It was 1 micron.

[C] Preparation of palladium sulfide core solution (Preparation M of ``r(4) Physical development nucleus'') A physical development nucleus solution made from palladium sulfide was prepared by mixing sodium sulfide and palladium chloride in an aqueous polyvinyl alcohol solution. .

High-sensitivity silver iodobromide emulsion [Ca] prepared as above.
b] Desensitized iodosilver chloride emulsion [C] Palladium sulfide core solution and [dl Separately synthesized SR, R compound [■]-5 were incorporated into gelatin using an oil dispersion method, and a gel was used to coat the gel on a paper support. The sample of the present invention shown below was prepared by applying the same to the following.

Sample 1 A sample in which a layer containing Ca) and I:d:lt- was coated on a paper support, and then a layer containing [b] and [C] was coated.

However, for Ca), the coating silver amount is 0.22 f/rr?
, [b], the amount of coated silver is 0.55 f/s, [C
], the coating amount was 4.8X10- with palladium sulfide.
'mol ~ Also, for (d), the coating amount is [111-5
The compound was applied at a concentration of 0.4 mmol/m'.

Sample 1 of the present invention prepared as described above was subjected to wedge exposure, and then exposed to light at 20°C using a developer having the composition shown below.
Development was performed for 0 seconds.

Developer ■ (comparison): Developer ■ (invention): Developer solution 1000-[■]-1
Developer solution to which the compound of is added Developer solution ■ (this invention): Developer solution ■1ooo- to [■]-3
Developer solution (comparison): Developer solution (comparison): Methylhydroquinone (E 1/2 (Ox, ) = -2 as a comparison to developer ■ 1000-
65mV vs SCE at pH=13.0)
The sample was developed with a developer containing 100% chloride, fixed with a commercially available Kodak F-5 fixer (manufactured by Eastman Kodak, USA), washed with water, dried, and then subjected to IJ-measurement. The results shown in 1 were obtained.

From the results shown in Table 1, it can be seen that the method of the present invention provides negative images with high maximum density and suppressed capri. Also, I) oxidation half-wave potential at H=13.0 -2
The comparative compound methylhydroquinone, which has a voltage of 00 mV or less, shows an effect similar to that of the present invention when added in a small amount, but when the added amount is increased, the redox reaction between SRR and ETA is inhibited, so that almost no image is given in the exposed area. On the other hand, it can be seen that in the case of the present invention, the desired effect is obtained regardless of the amount of the compound [■] added.

Example 2 High-sensitivity silver iodobromide emulsion [a] same as used in Example 1 [
b] Desensitized silver chlorobromide emulsion [C] A palladium sulfide core solution and [d] Dispersed gelatin containing 8RR, compound [11) -5' were used to prepare the samples of the present invention shown below.

Sample 2: A sample in which a layer containing [a] and [d) t- was coated on a paper support, a layer containing [b] was coated on top of which a layer containing [c] was coated on top of that.

However, for [a], the coated silver coin is 0.281β, [b]
For [c], the coating amount was 0.65 f/rd, and for [c], the coating amount was palladium sulfide, 1.4 x 10-'
For mol /, 1 or [d], the coating amount is I:I
[:l-5 compound was applied at a concentration of 0.6 mmol/m'.

Sample 2 of the present invention prepared in the manner described above was subjected to wedge exposure and then developed for 60 seconds at 25° C. with a developer having the composition shown below.

Developer ■ (comparison): Developer ■ (invention): Developer in which CD-1 compound was added to developer ■Developer ■ (invention): Developer in which [:IJ-2 compound was added to developer ■] Developer solution Developer solution ■ (comparison): As a comparison to developer ■, Hydrokino 7 (El/2 (Ox,) = -205mV vs.
8CBat pH=13.0) After development, the sample was treated in the same manner as in Example 1, and the amount of silver was measured in the exposed and unexposed areas of the obtained sample, and the silver precipitated on the surface was peeled off and the sample was processed again. The amount of silver was measured and the amount of silver deposited on the surface was calculated, and the results shown in Table 2 were obtained.

From the results shown in Table 2 and above, it can be seen that only the method of the present invention is an excellent negative image forming method that provides sufficient surface deposited silver in image areas and suppresses fogging silver in non-image areas.

Example 3 Sample 3 A sample is prepared in which a layer having the same composition as that prepared in Example 2 is coated on a polyethylene terephthalate film support.

However, for [a], the amount of coated silver is 0.25? /rr?
, [:b:1, the coating silver amount is 0.68? β, [C
], the coating amount is palladium sulfide 1.4 x 1
For 0-'mo1~[d], the coating amount is I:I[
]-5 to give a concentration of 0.5 mmol/m', and further added 0.6 υ of silica gel powder (Syroid 5Y-308, Fuji Davison M) as a matting agent to the emulsion layer containing [b, le. The coating was performed using

After image exposure of the obtained sample, the developer of Example 2 ■ (comparison)
, developer ■ ([I:]-1 content: 20F) (this invention)
The plate was developed for 50 seconds at 25° C. using a developer solution (hydroquinone content: 20 f) (comparison), and further processed in the same manner as in Example 2 to prepare a negative printing plate.

For the above samples, the printing plate was coated with a sensitizing solution (SLM-OH solution).
After wiping with Mitsubishi Paper Mills ■ and applying oil sensitization treatment, use ordinary offset printing ink and apply SLM-O as a wetting liquid.
When applied to an offset printing machine using Liquid D (manufactured by Mitsubishi Paper Mills@), only the sample of the present invention treated with developer ■ gave a clear ink image with risk of ink stains in non-image areas; In all of the comparative samples, no ink was applied to the image area, and the ink stain in the non-image area was severe, so that a proper ink image could not be obtained.

From the above, it can be understood that the negative image forming method of the present invention can be applied to the production of excellent negative planographic printing plates without fog.

Claims (1)

[Claims] On the support, (1) photosensitive silver halide (2) metal salt particles having substantially no photosensitivity (3) metal salt particles of (2) which react with the oxidized developing agent produced by development. A photosensitive photographic element containing a combination of a compound that releases a compound that acts as a dissolving agent or a dissolving physical development accelerator and (4) physical development nuclei is subjected to imagewise exposure and then developed to obtain the above-mentioned (2) in the exposed area. In the negative image forming method comprising the step of selectively depositing metal salt particles as a metal image on the physical development nuclei of (4) above, the processing solution used for the development processing is applied to a saturated calomel electrode at pH = 13.0. 1. A negative image forming method comprising a hydroquinone derivative having an oxidation half-wave potential of -200 mV or more.