JPS5816171B2 - Lith type silver halide photographic material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a silver halide photographic material, and particularly to a novel lithium-type silver halide photographic material.

Lithium-type silver halide photographic materials are used in the printing industry for special purposes such as obtaining halftone images, line drawings, etc. for use in photolithography.

Furthermore, Lith-type silver halide photographic materials are generally used in combination with a special developer called Lith developer, which is an infectious developer containing hydroquinone as a developing agent and having a low concentration of free sulfite ions.

Therefore, due to its special usage and development method, lithium-type silver halide photographic light-sensitive materials are different from ordinary black and white films,
They are required to have photographic performance different from that of X-ray films, color films, and other general silver halide photographic materials.

That is, while high sensitivity and low fog are the most important photographic performances for general silver halide photographic materials, in lithium-type silver halide photographic materials, artificial light sources with high illuminance can be used and Because a special development method is used, particularly high sensitivity is not required, and fog is hardly a problem, and furthermore, so-called so-called problems that are hardly a problem or are completely unrelated to ordinary silver halide photographic materials. Squirrel characteristics are required.

The first required characteristic is high contrast.

Conventional techniques for increasing contrast include a method of adding metal salts such as cadmium, rhodium, and iridium when forming silver halide grains, or a method of incorporating a polyethylene oxide compound into a light-sensitive material after grain formation. ing.

However, among these metal salts, cadmium is difficult to use due to its toxicity and pollution generation, rhodium salts also have strong desensitization properties, and iridium is effective in preventing softening during high-intensity exposure, but It has little effect on increasing contrast with normal exposure.

In addition, polyethylene oxide compounds are used in many lithium-type silver halide photographic materials, but in order to obtain a high-contrast halftone image using this method, a considerably long lithium development time is required. Due to the high hydrophilicity of the compound,
During the Lith development process, alkylene oxide compounds contained in the photosensitive material are eluted into the processing solution and accumulated.
It has disadvantages such as inhibiting lithographic developability, causing a significant decrease in sensitivity and contrast, and reducing the number of times the processing solution can be used. Appropriate.

Furthermore, it also has drawbacks in terms of viscosity adjustment during coating of silver halide photographic emulsions.

The second property required as a lithographic property is high halftone dot quality.

Unlike the method used for normal photosensitive materials, Lith-type silver halide photographic materials are used to produce continuous gradation by placing a screen in close contact with the Lith-sensitive material and performing Lith development in which oxidation and reduction proceed simultaneously. Converts changes in the density of the subject into the size of high-density halftone dots.

The outline of the halftone dots obtained at this time must be particularly clear, and this depends on the halogen composition, crystal habit, and grain size distribution of the silver halide grains, as well as the development inhibitor, development accelerator, and enhancer used in combination. Although it is known that it is closely related to the sensitivity of dyes, developing agents, etc., the details of its principle etc. are unknown.

Furthermore, if the halogen composition of silver halide grains is determined so that only the halftone quality is optimized, other photographic properties such as sensitivity and development speed are often impaired.

Furthermore, during lithographic development, black spot failures of several tens to several hundred microns may occur.

The cause of this failure is not fully understood, and therefore countermeasures are still unclear.

It is only known that factors similar to halftone quality are involved.

The object of the present invention is to provide a lithium-type silver halide photographic sensitizer with improved lithographic characteristics, that is, lithographic developability, high contrast and high-quality halftone dot performance, and less occurrence of black spot defects. The goal is to provide materials.

The inventors have undertaken extensive research to achieve the above objectives and others that will become apparent below.

At that time, it became clear that the effects of the same photographic additive have no correlation between ordinary light-sensitive materials and lithium-type silver halide photographic materials, and often appear in opposite directions. there were.

As an example, polyethylene oxide compounds are good sensitizers for general photosensitive materials, but exhibit a desensitizing effect on lithographic photosensitive materials.

For these reasons, with regard to photographic additives that are thought to be involved during development, the techniques used in general photosensitive materials are almost useless or unreliable, and the inventors believe that both silver halide photographic materials We came to the conclusion that it should be considered a photosensitive material that belongs to the Shibetsu category.

In fact, the inventors of the present invention were able to effectively achieve the object of the present invention for the first time by taking an approach based on this way of thinking.

That is, these purposes are to contain at least one of the water-soluble compounds of the following metals in a silver halide emulsion layer containing silver chlorobromide or silver chloroiodobromide containing 65 moles or more of silver chloride. A lithium-shaped silver halide photographic material characterized by:

2X10' to 8X10-' per mole of silver halide
Water-soluble compounds of zirconium in moles per mole of silver halide 1X10-5 to 5XIO-3 moles of water-soluble compounds of niobium Water-soluble compounds of antimony from 2x10゛6 to 1x10-4 moles per mole of silver halide Compound 3X10' per mole of silver halide to 2x10-3 mole of water-soluble compound of osmium 3X1 per mole of silver halide
0""6-5x10□4 moles of strontium water-soluble compound per mole of silver halide 5xio-'-6-2X10-
This was achieved using a water-soluble compound of neodymium.

In the present invention, in a combination of a silver halide emulsion having the limited silver halide composition described above and a special development method called lithography, at least one of the water-soluble compounds of the metals described above is added to the emulsion within the concentration range described above. However, if the silver halide composition, the development method, the type of metal, and its concentration are changed, the desirable and sufficient lithium properties cannot be obtained. This can be said to be a discovery of an extremely unexpected effect.

The water-soluble compound of the above-mentioned metal used in the present invention may be any compound of the above-mentioned metal that exhibits water-solubility, but preferred compounds include the following.

Zirconium chloride ZrC64 Zirconium oxychloride ZrOCg□・8H20 Zirconium bromide Zr Br4 Zirconium hydroxide Zr(OH)4 Potassium hexafluorozirconium K2 Zr F6 Zirconium sulfate Zr(SO4)2・4H20 Niobium chloride
NbC65 Niobium oxychloride Nb0Ce3 Niobium bromide NbBr3 Niobium hydroxide Nb(OH)5 Antimore chloride sbcg3.5bC6° Antimony oxychloride Sb OCg Antimony bromide Sb Br3 Antimony sulfate Sb2 ('S 04)3 antimonic acid 5b205 x H2O antimonite H3Sb03 Osmium chloride 03Ce4,05Ce2 Ammonium hexachloroosmate (NH4) 20s Ce6 Osmate 0504 Strontium chloride 5rCe2・6H20 Strontium bromide S r Br 2・6H20 Strontium nitrate Sr (NO3) Strontium dihydroxide Sr(O H) 2.8H20 chloride Naodium N
dCe3 Neodymium nitrate Nd (NO3) 3・6H2
0 Neodymium sulfate Nd2 (804) s・8H
20 Two or more of these compounds within the above concentration range can be used in combination.

The compound according to the present invention is contained in a silver halide photographic emulsion layer.

These compounds are preferably added as an aqueous solution or an aqueous gelatin solution to the silver halide emulsion during the formation of silver halide grains, during physical ripening or chemical ripening, or before coating thereafter. It is preferable.

Further, if an aqueous gelatin solution is used in which the compound according to the present invention is added within the above concentration range after metal cations in gelatin are removed using an ion exchange resin, the squirrel effect may be significant.

The appropriate amount of the water-soluble compound of the metal used in the present invention is within the above-mentioned range for each type of metal per mole of silver halide. Otherwise, the object of the present invention cannot be achieved because of the inversion.

Further, the optimum amount to be added differs depending on the time of addition, and when it is added at the time of silver halide grain formation, a smaller amount is appropriate than when it is added afterwards.

The lithium-type silver halide photographic material according to the present invention contains the water-soluble metal compound of the present invention alone or in combination with suitable photographic additives in an emulsion layer, and is coated on a suitable support. However, in general, a silver halide emulsion layer, an intermediate layer, a filter layer, and a protective layer are coated on a support that is backed or subbed as necessary.

The silver halide emulsion layer can include two or more layers sensitized to different wavelength ranges, and each emulsion layer can contain the compound of the present invention.

The lithium-type silver halide emulsion used in the present invention is a hydrophilic colloidal dispersion of silver chlorobromide or silver chloroiodobromide containing silver chloride in a molar ratio of 65 or more.

As the hydrophilic protective colloid which is a dispersant for silver halide, various colloidal substances such as gelatin, synthetic resins such as polyvinyl alcohol, or gelatin derivatives are used alone or in combination.

Further, this lithium-type silver halide emulsion can be chemically sensitized using a gold sensitizer, a sulfur sensitizer, or the like, or it can be optically sensitized using a sensitizing dye such as a cyanine dye or a merocyanine dye.

Furthermore, various kinds of photographic additives can be added, such as contrast enhancers such as palladium, platinum, rhodium, and cobalt, stabilizers or antifoggants such as triazole, tetrazole, and tetrazaindene compounds, formaldehyde, mucobromic acid, etc. halogen-substituted acids, hardening agents such as ethyleneimine compounds, spreading agents such as saponin, lauryl or oleyl monoether of polyethylene glycol,
Glycerin, ester of ethylene glycolic acid, polyvinylpyrrolidone, aqueous dispersion of synthetic resin (so-called lux)
Physical property improvers such as, halftone dot improvers such as alkylene oxide derivatives, lithium development accelerators such as imidazole and mercaptoimidazole compounds, etc. can be added within a range that does not impair the effects of the present invention.

As the support for the lithium-type silver halide photographic light-sensitive material according to the present invention, various polyesters including polyethylene terephthalate are typically used, but various other supports may be used depending on the purpose. For example, a synthetic resin such as polycarbonate, cellulose triacetate, or glass is used.

For developing the lithium-type photosensitive material according to the present invention, a hydroquinone-based developer containing sulfide ions at a relatively low concentration, ie, a lithium developer, is used.

The composition of the Lith developer is mainly composed of a dihydroxybenzene-based developing agent such as hydroquinone/S halogen-substituted hydroquinone or alkyl-substituted hydroquinone, alone or as a mixture, and an adduct of an aldehyde-bisulfite alkali salt, cyclohexane or acetone. A developing agent consisting of a compound having a carbonyl group (C=O), such as an adduct of a soluble sulfite, and an adduct of the soluble sulfite, or a condensation product thereof with an aliphatic primary or secondary amine. Preservatives, alkali agents such as alkali carbonates, alkali borates, and organic amines may be mentioned.

Furthermore, ascorbic acids, phenols, resorcinols, pyridazines, cysteines, primary, secondary or tertiary
amines, hydrazines, hydroxyamines, histidines, etc.; antifoggants such as 6-nidropentimitasol, 5-nitrointasol, 1-phenyl-mercaptotetrazole; triethylene; Organic solvents such as glycols such as glycols, amines, and alcohols, halftone improvers such as polyalkylene oxides, etc. can also be used.

The present invention will now be illustrated by examples, but the embodiments of the present invention are not limited thereto.

Example 1 A silver chlorobromide emulsion having an average grain size of 0.31 μm and containing 25 moles of silver bromide was prepared according to a conventional method for producing a lithium-type silver halide emulsion.

At this time, each material was prepared by adding zirconium sulfate in the amount shown in Table 1 below when forming silver halide grains.

The resulting emulsion was sensitized with gold and sulfur, and further had an average molecular weight of 40.
00 polyethylene oxide, formalin, saponin, anhydro-3/(δ-sulfobutyl)-selenocarbocyanine hydroxide and 4-methyl-6
-Hydroxy-1,3°3a,7-chitrazaindene was added, and the mixture was coated and dried on a subbed polyethylene terephthalate film support to a dry film thickness of 5 μm.

The obtained sample was measured using a KS-7 type sensitometer (manufactured by Konishiroku Photo Industry).
The results were shown in Table 1 below. Shown below.

Note that the sensitivity is expressed as a relative value, with the sensitivity of sample number 1 being 100.

As is clear from Table 1, the amount of water-soluble zirconium compound added in the present invention is 1 mole of silver halide.
If it is less than 0.01 mol, it has almost no effect on γ;
It can be seen that at 0-2 mol or more, desensitization appears and γ also decreases.

Example 2 Into a 25th gelatin aqueous solution, 16th silver nitrate, 0.6th alkali halide, and 10-5 mol of zirconium sulfate per 1 mol of silver halide were mixed using a tuple jet method.
Physical ripening was performed at 65° C. for 10 minutes to obtain silver chlorobromide emulsions having an average grain size of 0.20 μm and different silver chloride compositions.

This was sensitized with gold and sulfur, and the same photographic additives as in Example 1 were added, coated on a polyester base, and dried.

However, 1-(β-hydroxy)-3-phenyl-5-(3-(
γ-sulfopropyl)-α-penzoxazolinylideneethylidene]-2-thiohydantoin was added.

Roughten 58 filter (manufactured by Eastman Kotak)
was turned on, and high-intensity exposure was performed for 10-5 seconds using a xenon flash lamp.

This was treated with the above D-851J developer and subjected to sensitometry.

The results are shown in Table 2 along with the silver halide composition.

However, the γ increase rate in the table is expressed as the ratio of γ when zirconium sulfate is added to γ when zirconium sulfate is not added in each sample.

It can be seen from Table 2 that the contrast enhancement effect of zirconium sulfate is extremely pronounced when silver chloride has a molar concentration of 65 or more.

In the same manner as in this example, silver chloride iodobromide containing 1 mole of silver iodide was examined by changing the ratio of silver chloride and silver bromide, but the results showed that silver chloride was 65% silver iodide as in this example. High contrast was observed only when the content exceeded the molar coefficient.

Reference Example Instead of developer D-85 used in Example 2, general black and white developer A1 with the following formulation and color negative developer B for rapid processing were used.
Table 3 shows the γ increase rate when processing with 1. X-ray film developer for rapid processing D1. 1st developer for color reversal 0.1 Developer for color photographic paper E.

From the comparison of Tables 2 and 3 above, it can be seen that the effect of increasing contrast cannot be obtained by developing methods other than Lith developer.

Example 3 A lithium-type silver chloroiodobromide emulsion containing 80 moles of silver chloride and 1 mole of silver iodide was prepared in the presence of the metal salts shown in Table 4 below.

This was gold-sulfur sensitized, and the same additives as in Example 1 were added to create a lithium-shaped photosensitive material. A contact screen was attached to the material, and a helium-neon laser oscillator (manufactured by NEC Corporation, GAS LASER GLG) was prepared. -2004
) using a helium-neon laser light of 10-5
Exposure for seconds.

This was developed at 27°C using a developer with the following composition for 1 time.
Development was carried out at 10 second intervals from minute 20 seconds to 2 minutes 20 seconds.

Developer Composition The halftone dot quality and black spot occurrence were measured under a microscope for the sample with the least fringes at each development time, and the best one was evaluated as 5 and the poor one as 1. The results are shown in Table 4. It was shown to.

It can be seen from Table 4 that the addition of the compounds according to the invention improves the dot quality and the occurrence of black dots.

Example 4 According to Example 3, the metal compounds listed in Table 5 below were added,
Photographic performance was evaluated.

However, the photosensitive needle used was the KS-7 type (tungsten light source).

The results are shown in Table 5.

From Table 5, except for sample 35 and 4 12 related to the present invention,
It is understood that the objectives of the invention may not be achieved.

Note that cadmium in sample A35 is highly toxic and is a compound that should not be used industrially.

Test Example "Sakurapan Lith" (manufactured by Konishi Roku Photo Industry Co., Ltd.) is used as a typical lithium-type silver halide photographic light-sensitive material.The metals in the light-sensitive material are measured using a spark ion source mass spectrometer JMS-OIBM-2 model (manufactured by JEOL Ltd.). Compounds were quantified.

The results are shown in Table 6 below. Table 6 shows that the content of the metals according to the present invention in conventional lithium-type silver halide photographic light-sensitive materials is very small. It turns out that the purpose is not achieved.

Claims (1)

[Scope of Claims] 1. At least one of the water-soluble compounds of the following metals is contained in a silver halide emulsion layer containing silver chlorobromide or silver chloroiodobromide containing 65 moles or more of silver chloride. A lithium-shaped silver halide photographic material characterized by: Water-soluble compounds of zirconium from 2X10' to 8xlO' moles per mole of silver halide Water-soluble compounds of niobium from 1x10-5 to 5X10''3 moles per mole of silver halide 2X10-6 per mole of silver halide ~ 1X10' mole of a water-soluble compound of antimony 3x10-6 to 2X10-3 mole of a water-soluble compound of osmium per mole of silver halide 3x10-6 to 5X10-' mole of strontium per mole of silver halide Water-soluble compounds of 5X106 to 2X10' moles of water-soluble compounds of neodymium per mole of silver halide