JPS6359137B2 - - Google Patents

Description

[Detailed description of the invention]

(A) Industrial Application Field The present invention relates to a processing solution for silver complex diffusion transfer. (B) Prior art and its problems The principle of the silver complex diffusion transfer method (hereinafter referred to as the DTR method) is described in the specification of U.S. Patent No. 2,352,014, and there are many other patents and documents. Are known. In other words, under the DTR method,
Silver complex salts are imagewise transferred from the silver halide emulsion layer to the image-receiving layer by diffusion, and they are converted into a silver image, often in the presence of physical development nuclei. For this purpose, an imagewise exposed silver halide emulsion layer is placed in contact with, or brought into contact with, an image-receiving layer in the presence of a developing agent and a silver halide solvent, and the unexposed halide emulsion layer is Converts silver into soluble silver complexes. In the exposed portions of the silver halide emulsion layer, the silver halide is developed to silver so that it cannot be further dissolved and therefore cannot be diffused. In the unexposed areas of the silver halide emulsion layer, the silver halide is converted to a soluble silver complex salt,
They are transferred to the image receiving layer where they form a silver image, usually in the presence of development nuclei. The DTR method is used to reproduce documents, create lithographic printing plates,
A wide range of applications are possible, including the production of block printing materials and instant photography. In particular, when reproducing documents or preparing printing materials, a negative material having a silver halide emulsion layer and a positive material having an image-receiving layer containing physical development nuclei are used.
Usually, they are brought into close contact in a DTR processing solution containing a silver complex forming agent to form a silver image on the image-receiving layer of a positive material.
The silver image must be pure black or black with a bluish tinge, and must also have a sufficiently high density.
Furthermore, it is important to have high contrast and sharpness and good image reproducibility, and it is desirable that the transfer speed is high. Moreover, it is necessary that the good quality of the positive material does not depend greatly on the processing conditions (e.g. time, temperature), or that the quality does not deteriorate due to running processing (continuing to use the processing solution for a long period of time). . In general, image forming systems using the DTR method are
A very simple process is used. For example, the processor includes a tray for holding a transfer developer, a squeeze roller for bringing a negative sheet and a positive sheet into close contact with each other, and a motor for rotating the squeeze roller. Various types of processors have been designed and put into practical use by manufacturers in other countries, but in general,
With some exceptions, temperature control is not performed, and processing is generally performed at room temperature. Furthermore, the conveyance speed and path length in the developer vary depending on the processor. Based on the principle of the DTR method described above, it can be easily inferred that the image forming process will be greatly affected by processing conditions, especially processing temperature, processing speed, etc. It is also well known. General specific examples of characteristic changes caused by changes in the processing environment in the DTR method, especially changes in processing temperature and changes in conveyance conditions, are as follows: (1) Sensitivity, tone, color tone, density (reflection density, (2) Low-temperature processing tends to cause contamination (due to the formation of fine silver colloid) on the image-receiving sheet. (3) The ability to form minute images, such as fine lines or minute dots, is affected by the processing temperature. For example, it decreases as the conveyance speed increases or as the conveyance speed decreases. Although these are very serious issues, they have been ignored because the DTR method relies on a delicate balance between chemical development, dissolution, diffusion, and physical development, which is difficult to control. This is probably because it was thought to exist. Furthermore, another practical problem with the DTR system is the following. That is, in order to satisfy the above-mentioned quality to some extent, the formulation composition of each product has been studied and put into practical use as a combination of a negative material, a positive material, and a DTR processing liquid. That is, as a negative material,
Low-sensitivity products for contact printing, high-sensitivity products for camera work, products using direct positive emulsion, positive materials that use reflection density, and transmission density, and DTR processing liquids. Various materials and processing solutions are selected and combined depending on the method and manner of use, such as those containing a developing agent and those not containing a developing agent.
If any one of the positive materials, negative materials, and processing liquids that are combined to obtain the highest quality is used as a substitute for another combination product, each combination has the disadvantage that the original highest quality cannot be obtained. It was hot. It would be desirable if a versatile processing solution could be obtained that exhibits the above-mentioned good properties for any negative or positive material. (C) Purpose of the Invention The purpose of the present invention is to ensure that the quality does not deteriorate depending on the type of negative material and positive material and their combination, and that the quality can be maintained at high density, high contrast, even when processing conditions are changed or running processing is performed. It is an object of the present invention to provide a processing solution and processing method for silver complex diffusion transfer, which can obtain a silver image with high resolution and good color tone, and a high quality positive material without background stains. (D) Structure of the Invention The above object of the present invention is to provide a processing solution for silver complex diffusion transfer containing at least a silver halide developing agent and an amino alcohol that has a pKa value of 9 in an aqueous solution containing 50% by weight of ethanol (at 25°C). A treatment for a silver complex diffusion transfer method, characterized in that it contains at least one of each of an amino alcohol of less than Achieved by liquid. The present invention will be explained in more detail below. The pKa value of amino alcohol is, for example, "STABILITY CONSTANTS OF METAL".
ION COMPLEXES” (Special Publication No.17
(1964) and No. 25 (1971), THE
CHEMICAL SOCIETY, published by LONDON), “Chemical Handbook Basic Edition” (revised 3rd edition, June 25, 1982)
published by Nippon Maruzen Co., Ltd.), etc.
It can also be easily measured. The pKa value in the present invention is defined as one measured at 25° C. in a mixed solvent of ethanol and water at a weight ratio of 50:50. However, in this specification, the pKa value of an amino alcohol in an aqueous solution is referred to as pKa [water]
It may be indicated that The value of pKa [water] is generally slightly higher (about 0.2) than the pKa value of the above mixed solvent, and for example, the following relationship exists.

[Table] Furthermore, the pKa [water] of amino alcohol is generally
It's getting higher. The use of amino alcohol in the DTR processing solution is described, for example, in JP-A No. 48-93338, and is known to have the effect of preventing the oxidation of silver halide developing agents, that is, as a preservative. . However, amino alcohols also act as alkaline agents. Therefore, it was found that when combined with an inorganic alkali agent, the amount of the alkaline agent becomes very large, which tends to cause disadvantages such as a decrease in concentration, and also worsens the running processability.As a result of intensive research, we found that combining an inorganic alkali agent, e.g. It has been discovered that the object of the present invention can be achieved by not containing sodium hydroxide, potassium hydroxide, etc., or by containing only a small amount, and by combining amino alcohols having different pKa values. It is. Although not bound by speculation, the present invention can be better understood by explaining the rationale below. In other words, the factors that cause the various properties of a realistic DTR processing solution to change as the running process continues include, for example, a decrease in the processing agent due to the sheet material, changes in composition, a decrease in pH, and water (and volatile processing agents). ), concentration due to evaporation, PH decrease due to absorption of carbon dioxide gas in the air, and oxidation of the developing agent. Among these, the present inventor found that not only the oxidation of the developing agent but also the absorption of carbon dioxide gas has an extremely large effect, and as a result of intensive research into a solution to this problem, the above-mentioned solution was found.
By combining at least one amino alcohol with a pKa value of less than 9 and at least one amino alcohol with a pKa value of 9 or more, it is possible to control the processing conditions from immediately after preparation of the processing solution to longer-term running processing. It has been discovered that better properties than ever before can be stably obtained. and pKa
Amino alcohols with a value of less than 9 and amino alcohols with a value of 9 or more are treated liquids that have absorbed carbon dioxide gas, that is, the amino alcohols used in the present invention are primary, secondary, or tertiary amine compounds having at least one hydroxyalkyl group. and particularly preferably secondary or tertiary amines. Amino alcohols include compounds represented by general formula (A). General formula (A) (X and X' represent a hydrogen atom, a hydroxyl group, or an amino group. l and m represent an integer of 0 or 1 or more, and n represents an integer of 1 or more.) Specifically, ethanolamine, diethanolamine, triethanol Amine, diisopropanolamine, N-methylethanolamine, N-
Aminoethylethanolamine, N,N-diethylethanolamine, N,N-dimethylethanolamine, N-methyldiethanolamine, N-
Ethyldiethanolamine, 3-aminopropanol, 1-amino-propan-2-ol, 4-
Aminobutanol, 5-amino-pentane-1-
Examples include ol, 3,3'-iminodipropanol, and N-ethyl-2,2'-iminodiethanol. Furthermore, the aforementioned 2-amino-2-(hydroxymethyl)propane-1,3-diol and 2-amino-2-methylpropane-1,3-diol can also be used. Generally speaking, the pKa value defined above is that amino alcohols having one hydroxyalkyl group have pKa9.
Based on the above, it can be said that an amino alcohol having two or more hydroxyalkyl groups has a pKa of less than 9. The difference in pKa values of the amino alcohols to be combined is preferably 0.3 or more, preferably 0.5 or more. Experiments have confirmed that these substances have a lower pKa and a higher pKa than that of carbonic acid (H ₂ CO ₃ ). Therefore, even if the processing solution absorbs carbon dioxide gas, the amino alcohol with a pKa of less than 9 will ensure the developing ability. However, from the above explanation, it is understood that amino alcohols with a pKa value of less than 9 can greatly improve running processability, but they alone may not provide sufficient photographic properties, especially during low temperature processing, or may not be suitable for running processing. Therefore, there is a drawback that contamination may occur on the image receiving sheet, and these drawbacks can be solved by combining an amino alcohol with a pKa value of 9 or more, and at the same time adding an inorganic alkaline agent to 0.2 mol or less per processing solution, preferably 0.15 mol to 0. The problem can be solved by converting it into moles, and the present invention has been completed. Of course, oxidation of the developing agent by amino alcohol can also be suppressed. The total amount of amino alcohol used is preferably in the range of 0.3 to 2 moles per 1 processing solution (working solution). The molar ratio of amino alcohols with pKa values of less than 9 and amino alcohols with pKa values of 9 or more is preferably in the range of 2:8 to 8:2. The silver halide developing agent used in the processing solution of the present invention is preferably a P-dihydroxybenzene compound, such as hydroquinone, methylhydroquinone, chlorohydroquinone, etc., and is preferably in the range of 0.07 to 0.2 mol per processing solution. The treatment liquid of the present invention preferably contains 1-phenyl-3-pyrazolidone (and its derivatives) in addition to P-dihydroxybenzene. However, 3-
Pyrazolidone may be included in various negative and/or positive materials. 1-phenyl-3
-The amount of pyrazolidone is preferably in the range of 2×10 ⁻³ to 2×10 ⁻² mol/. The processing solution of the present invention may further contain a preservative, such as 0.3 to 0.7 mol of sodium sulfite, and a silver halide solvent, such as sodium thiosulfate or potassium thiocyanate, of 0.02 to 0.15 mol. Furthermore, thickening agents such as carboxymethyl cellulose, hydroxyethyl cellulose, antifoggants such as potassium bromide, benzotriazole, toning agents such as 1-phenyl-5-mercapto-tetrazole, developer modifiers such as polyoxyalkylene compounds, grade ammonium salts, development nuclei such as those described in GB 1001558. A typical negative material for the DTR method is composed of at least one silver halide emulsion layer provided on a support, and the silver halide content, calculated as silver nitrate, is generally in the range of 0.5 g to 3.5 g/ ^m2 . applied. In addition to this silver halide emulsion layer, auxiliary layers such as an undercoat layer, an intermediate layer, a protective layer, and a release layer are provided as necessary. For example, the negative material used in the present invention is a water-permeable binder such as those described in Japanese Patent Publication No. 38-18134 and 18135, etc., such as methyl cellulose, sodium salt of carboxymethyl cellulose, sodium alginate, etc., which are halogenated. It can be used as a covering layer for the silver emulsion layer to ensure uniform transfer, and this layer is so thin that it does not substantially prevent or suppress diffusion. silver halide emulsion layer in negative material,
The image-receiving layer of the positive material contains hydrophilic colloid substances such as gelatin, gelatin derivatives such as phthalated gelatin, cellulose derivatives such as carboxymethyl cellulose and hydroxymethyl cellulose, dextrin, soluble starch, polyvinyl alcohol, and polystyrene sulfone. Contains one or more types of hydrophilic polymer colloid substances such as acids. The silver halide emulsion consists of silver halides, such as silver chloride, silver bromide, silver chlorobromide, and iodides thereof, dispersed in the above-mentioned hydrophilic colloid. Silver halide emulsions can be sensitized in a variety of ways when they are manufactured or coated. Chemically sensitized by methods well known in the art, such as with sodium thiosulfate, alkylthioureas, or with gold compounds such as gold rhodan, gold chloride, or a combination of both. Good too. The emulsions are further sensitized, usually to a range of about 530 to about 560 nm, but can also be panchromatically sensitized. Direct positive silver halide emulsions may also be used. The silver halide emulsion layer and/or the image-receiving layer may contain any compound commonly used for carrying out the silver complex diffusion transfer method. These compounds can include, for example, fog suppressants such as tetrazaindene and mercaptotetrazoles, coating aids such as saponin and polyalkylene oxides, hardeners such as formalin and chrome alum, and plasticizers. It may contain a developing agent. The support used for negative or positive materials is any commonly used support. These include paper, glass, films such as cellulose acetate film, polyvinyl acetal film, polystyrene film, polyethylene terephthalate film, etc.; metal supports coated on both sides with paper;
Paper supports coated on one or both sides with an α-olefin polymer, such as polyethylene, can also be used.
The positive material may contain physical development nuclei, such as heavy metals or their sulfides. In one or more layers of the positive material, substances which play a significant role in the formation of the diffusion transfer image, such as black toning agents such as those described in British Patent No. 561,875 and Belgian Patent No. 502,525, such as -Phenyl-5-mercaptotetrazole may be included. The positive material may also contain a fixing agent such as sodium thiosulfate in an amount of about 0.1 to about 4 g/m ² . (E) Examples The present invention will be explained in more detail below using examples, but is of course not limited to these. Example 1 [Positive material A] An image-receiving layer consisting of a processed product of PVA containing palladium sulfide cores, an ethylene/maleic anhydride copolymer, and gelatin on one side of a 110 g/m ² paper support coated on both sides with polyethylene. Dry weight 3g/ ^m2
A positive material A was prepared by providing the following conditions. [Positive material B] Hardened gelatin image-receiving layer containing palladium sulfide nuclei on polyethylene terephthalate film
A positive material B was prepared by providing the amount of 3 g/m ² . [Negative material M] On the same paper support as positive material A, an undercoat layer containing carbon black for anti-halation is provided, and on top of that, silver chlorobromide (silver bromide 5 A negative material M was prepared by providing an ortho-sensitized gelatin silver halide emulsion layer containing 2.0 g/m ² of silver nitrate (mol%). [Negative Material N] Comparative emulsion B described in Example 1 of JP-A-57-96331 was used in place of the emulsion of negative material M to prepare a direct positive silver halide negative material N. Negative materials M and N were attached to an ordinary plate-making camera, exposed to light, and brought into close contact with positive materials A and B, respectively, for image transfer. The transfer processor used was a Mitsubishi paper transport speed variable type OSP-12 (trade name), and the processing liquid temperature was set arbitrarily. The transfer time was 30 seconds. For image exposure, thin lines from 10μ to 100μ (every 10μ) and reflective optical wedges are placed on the document, and the exposure amount is controlled from the wedge of the transferred image.
Further, the ability to form minute images was evaluated from the state of formation of thin lines. The photograph was taken at a 70% reduction of the original. Evaluation of Processing Condition Tolerance The processing liquid temperature was set to 10°C, 20°C, and 30°C, and the conveyance speed was changed so that the residence time of the negative material in the processor liquid was changed to 3 seconds, 6 seconds, and 9 seconds. Evaluation of running processability After processing 10 sets of A-4 size negative material and positive material per developer, each processing solution was opened for 4 days in a carbon dioxide atmosphere with dry ice, and the processing solution was The transfer process was performed again and the characteristics were evaluated. Table 2 shows the tolerance of processing conditions with the new solution, and Table 3 shows the evaluation of running processability. Furthermore, Table 2,
In Table 3, the conveyance speed of the processor was set so that the negative liquid residence time was 6 seconds. Table 1 shows the composition of the treatment liquid.

【table】

[Table] N-methylethanolamine has a pKa [water] of 10.1,
N-methyldiethanolamine has a pKa of 8.28.

【table】

【table】

[Table] The processing solutions F and I of the present invention not only provide a high transmission density, but also are stable against changes in processing temperature, are free from contamination during low-temperature processing, and have low halftone The color tone was good, the temperature dependence of practical printing sensitivity (expressed as relative sensitivity with sensitivity at 20°C processing as 100) was small, and the ability to form minute images was excellent. In addition, in similar experiments, regarding the relationship between the processing liquid temperature and the transport speed, it was found that the processing liquid of the present invention does not easily cause background yellow staining under the conditions of low temperature and high speed transport, while the micro image forming ability decreases under the conditions of high temperature and low speed transport. It was confirmed that the decrease was extremely small. Furthermore, it can be seen that the treatment liquid of the present invention has excellent running treatment properties. Example 2 Various properties of the following treatment liquids were checked in the same manner as in Example 1. (Negative (M), Positive (A),
(B) Use)

[Table] High temperature processability (30℃ processing, conveyance speed 9 seconds)
), low-temperature processability (judged from the occurrence of background yellow contamination at a conveyance speed of 4 seconds at 10°C), and running properties (judged from the background yellow contamination, similar to Example 1) We have summarized the following. (F) Effect of the invention The processing liquid of the present invention can be used in combination with various negative and positive materials and processed under various conditions by using amino alcohols with different pKa values in combination with a small amount or no inorganic alkaline agent. It is possible to obtain a good image even when running, and the running processability is very good.

Claims (1)

[Claims] 1 In a processing solution for silver complex diffusion transfer containing at least a silver halide developing agent and an amino alcohol, an aqueous solution containing 50% by weight of ethanol (25°C)
silver containing at least one kind of an amino alcohol having a pKa value of less than 9 and an amino alcohol having a pKa value of 9 or more, and further containing no inorganic alkali agent or an amount of 0.2 mol or less per processing solution Processing solution for complex salt diffusion transfer.