JPH0456969B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a silver complex diffusion transfer material that combines a light-sensitive material and an image-receiving material, and particularly relates to a method for producing an image-receiving material. The silver complex diffusion transfer method generally uses a light-sensitive material in which a silver halide emulsion is formed on a support as a light-sensitive layer, an image-receiving material in which an image-receiving layer containing physical development nuclei is formed on a support, and a silver halide solvent. It consists of a processing liquid containing The principle of the silver complex diffusion transfer method is that the silver halide in the exposed areas of the exposed photosensitive layer is developed by a processing solution or a developing agent in the photosensitive material, and at the same time, the silver halide in the unexposed areas is developed in the processing solution. It reacts with the silver halide solvent to form a soluble silver complex salt, which diffuses into the image-receiving material and deposits on physical development nuclei in the image-receiving layer to form a silver image. The silver complex diffusion transfer method based on this principle can be used to copy documents, such as printed matter, handwritten documents,
It is widely used for copying blueprints and as a material for plate making, and requires image reproduction that is faithful to the original manuscript. The important qualities of the image-receiving material used in the silver complex diffusion transfer method are high silver image density (reflection and transmission density) and good color tone (blue-black tone is generally desired).
It is important that the diffusion transfer speed is high and that the image-receiving layer has sufficient film strength. In particular, silver image density (reflection and transmission density) is a very important quality. Copies are generally required to have high image clarity, and if the silver image density is high, copies with high clarity can be obtained. In addition, when used as printing material, image quality (fine lines and net quality)
It is said that high silver image density is desirable for good reproduction. It is no exaggeration to say that the silver image density greatly influences the performance of image-receiving materials, and research and development efforts have been made in this industry to increase the silver image density of image-receiving materials. As is well known, the image-receiving material contains physical development nuclei as hydrophilic colloids, such as gelatin, gelatin derivatives,
Polyvinyl alcohol, partially silicified polyvinyl alcohol, maleic anhydride copolymer (e.g. styrene-maleic anhydride copolymer, ethylene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, vinyl methyl ether) maleic anhydride copolymers, vinyl acetate-maleic anhydride copolymers, etc.), and heated processed products of these maleic anhydride copolymers and polyvinyl alcohol,
Polyacrylamide, polyacrylic acid, poly-N
- Vinylpyrrolidone, emulsion polymerized synthetic resins (e.g., polyacrylic acid ester, polyacrylic acid, polymethacrylic acid, polymethacrylic acid ester, polystyrene, polybutadiene, etc. alone or copolymers, etc.), as well as carboxymethyl cellulose, hydroxyl It has an image-receiving layer in which ethyl cellulose, sodium alginate, dextran, gum arabic, agar, starch and its derivatives are dispersed. Generally, an image-receiving layer in which at least a portion of the hydrophilic colloid is gelatin is used, and it is dried at a low temperature to form a uniform film surface like a normal photographic light-sensitive layer by utilizing gelatin's sol or gelation phenomenon. It is normal to do so. The drying process is described in "Coating Engineering" by Yuji Harasaki (1971, Asakura Shoten), 278-281.
As described in page 1, the material preheating period, the constant rate drying period of the drying process in which the amount of solvent evaporation per unit time, that is, the evaporation rate of the solvent is constant, after which the evaporation rate of the solvent gradually decreases, The drying process is divided into three processes: a decreasing rate drying period until evaporation is almost eliminated (that is, the coating film has almost the equilibrium moisture content under the temperature and humidity conditions of the outside air), and a humidity control period is added as necessary. Sometimes. Normally, drying is completed when an equilibrium moisture content of about 5 to 8% is reached, but the temperature of the membrane surface during the drying process (in the present invention, this temperature is referred to as the surface wet bulb temperature) should be kept low. In other words, a uniform coating film was obtained, and an image-receiving material of good quality was obtained. By the way, various types of supports for image-receiving materials are known, such as polystyrene,
Examples include polycarbonate film, plastic film such as cellulose triacetate and polystyrene terephthalate, paper coated with resin such as polyethylene, and even baryta paper, which can be used depending on the purpose. Among the above-mentioned printing materials, there is an image-receiving material using a support made of resin-coated paper with a roughened surface, commonly called a matte surface. However, this image-receiving material has the disadvantage that it is difficult to obtain a high silver image density compared to an image-receiving material using resin-coated paper with a glossy surface. As a result of extensive research in order to solve the above-mentioned drawbacks, the present inventors have determined that the drying conditions are closely related to the drying conditions of the image-receiving layer and are contrary to the conventional knowledge as described above. We discovered the surprising fact that the problem can be solved by An object of the present invention is to provide a method for producing an image-receiving material comprising a support with a rough surface. Another object of the present invention is to provide a method for producing a rough-supported image-receiving material with high film strength and silver image density. The above-mentioned object of the present invention is to provide a method for producing an image-receiving material in which a coating solution for forming an image-receiving layer containing at least gelatin and physical development nuclei is applied to a rough-surfaced support and dried, wherein the gelatin concentration of the coating layer is at least about 30% by weight.
This was achieved by a method for producing an image-receiving material, which is characterized in that the surface wet bulb temperature of the coating layer is raised to 23° C. or higher before drying. Preferably, gelatin accounts for about 1/2 or more, preferably about 2/3 or more of the total amount of binder in the image-receiving layer. The coating solution for forming the image-receiving layer is generally preferably an aqueous solution containing a binder concentration in the range of about 2 to about 10% by weight. When the binder is gelatin alone, it is preferably an aqueous solution of about 4% to about 10% by weight. The method for coating the image-receiving layer in the production of the image-receiving material of the present invention may be a commonly used coating method (for example,
(air knife method, extrusion method, curtain method, etc.) are used. The amount applied can vary as desired, but generally ranges from about 1 to about 5 grams of binder per square meter.
It is preferable to apply it so that The applied image-receiving layer is first cooled and set,
Thereafter, hot air drying is performed while gradually increasing the temperature, and drying is completed when substantially no water evaporates. Today, the time from application to complete drying is less than 10 minutes or less than 5 minutes. However, even in such a short drying time, it was avoided as much as possible to increase the drying temperature for the applied amount of gelatin, for the reasons already mentioned.
In fact, if the drying temperature of an image-receiving layer coated on a smooth support, such as polyethylene resin-coated paper that has not been roughened, is raised during the drying process so that the surface wet bulb temperature is 23°C or higher, , the maximum reflection density of the silver image is obviously lower than that of an image-receiving material that is completely dried while its surface wet bulb temperature remains below 23°C. Nevertheless, the gelatin concentration in the image-receiving layer is gradually increased during the drying process so that the surface wet bulb temperature of the image-receiving layer coated on the rough surface support is 23°C or higher. , at the latest about 30% by weight
It has been found that the maximum density of the silver image is higher if the drying is completed by the time the silver image reaches . Even if the gelatin concentration becomes too high and the surface wet bulb temperature is raised to 23° C. or higher at or near completion of drying, the curing of the present invention is not substantially observed. Furthermore, if the surface wet bulb temperature is increased to 23°C or higher immediately after application, failures such as the paint film running will naturally occur. Therefore, after coating, the coated layer is cooled and set (gelled), and the surface wet bulb temperature must be kept below 23℃ until coating failures will not occur even if hot air is blown to reach a surface wet bulb temperature of 23℃ or higher. At least gradual drying is necessary. Its temperature is 23
The timing at which the temperature is raised to above 15°C varies depending on the composition of the image-receiving layer, the degree of surface roughening of the support, etc., but the gelatin concentration in the image-receiving layer is about 12% by weight or more, preferably about 15% by weight.
It is desirable that the amount exceeds % by weight. The required surface wet bulb temperature also varies depending on the composition of the image-receiving layer, the degree of surface roughening of the support, etc. The effect of the present invention begins to be obtained at temperatures above 23°C, and the effect increases as the temperature rises; Since the properties of the planar support may be lost, it is desirable to stop the temperature at about 35°C. Preferred is 23°C to 30°C. The surface wet bulb temperature roughly corresponds to the wet bulb temperature of the atmosphere surrounding the dry surface of the image receiving layer. The image-receiving layer of the image-receiving material can be hardened with a suitable hardening agent. Specific examples of the hardening agent include aldehyde compounds such as formaldehyde and glutaraldehyde, ketone compounds such as diacetyl and cyclobentanedione, and (2-chloroethylurea)-2-hydroxy-4,6-dichloro-1,
3,5 triazines, compounds with reactive halogens as described in U.S. Pat. No. 3,288,775, divinyl sulfones, compounds with reactive olefins as described in U.S. Pat. No. 3,635,718,
N-methylol compounds as described in US Pat. No. 2,732,316, isocyanates as described in US Pat. No. 3,103,437,
Aziridine compounds as described in US Pat. No. 3,017,280 and US Pat. No. 2,983,611; carbodiimide compounds as described in US Pat. No. 3,100,704; US Pat.
Epoxy compounds such as those described in No. 3091537, halogencarboxaldehydes such as mucochloric acid, dioxane derivatives such as dihydroxydioxane,
There are inorganic hardeners such as chromium alum, potash alum, and zirconium sulfate.
More than one species can be used in combination. Physical development nuclei used in the image-receiving layer of the image-receiving material according to the present invention include silver, gold, platinum, palladium,
Precious metals such as copper, cadmium, lead, cobalt, and nickel, or their sulfides, selenides, and the like can be used. These are preferably colloidal. The image-receiving layer contains surfactants (for example, natural surfactants such as saponin, nonionic surfactants such as alkylene oxide, glycerin, and glycidol, higher alkyl amines, quaternary ammonium salts, pyridine and other heterocycles, Cationic surfactants such as sulfoniums, carboxylic acids, sulfonic acids, phosphoric acids, sulfuric acid ester groups, anionic surfactants containing acidic groups such as phosphoric ester groups, amino acids, aminosulfonic acids, sulfuric acid or phosphoric acid esters of amino alcohols amphoteric surfactants such as fluorine-containing anions and amphoteric surfactants), matting agents, fluorescent dyes, discoloration inhibitors, color toning agents (typical examples include 1-phenyl-5-
mercapto-tetrazole, other color toning agents described in Focal Press Publishing, Photographic Silver Halide Distillation Process, page 61), developing agents (e.g., hydroquinone and its derivatives, 1-phenyl-3-pyrazolidone and its derivatives) etc.), silver halide solvents (e.g.
sodium thiosulfate, ammonium thiosulfate, sodium thiocyanate, potassium thiocyanate, etc.). Further, an over layer (for example, an over layer using lime-treated gelatin, acid-treated gelatin, hydroxyl ethyl cellulose, carboxyl methyl cellulose, bullulan, sodium alginate, etc.) on the image-receiving layer, a neutralizing layer below,
A subbing layer may be provided to improve adhesion to the support. The rough surface support used in the present invention may be any material such as a polyolefin resin film such as polyethylene or polypropylene, or paper coated with the same, as long as its surface is roughened. Examples of methods for roughening the surface include a solvent processing method, a foaming method, and a compression molding method using a rough surface body, and any method for roughening the surface may be used. Surface roughness is approximately 2 to 20 μm in depth, which is the distance from the depression to the top of the surface unevenness, and approximately 5 to 100 μm in size, which is the distance from peak to peak. is desirable. Since the roughened resin surface is hydrophobic as it is, it is generally subjected to some kind of hydrophilic treatment such as corona discharge treatment or subbing treatment.
The resin may contain a white pigment, a fluorescent dye, an antistatic agent, and the like. The silver halide emulsion used in the photosensitive layer of the photosensitive material for silver complex diffusion transfer according to the present invention is an emulsion commonly used for diffusion transfer, and there are no strict regulations on the composition of this emulsion. Silver bromide, silver iodide, silver chloride, silver chlorobromide, silver iodobromide, silver bromide, silver iodide, silver chloride, silver chlorobromide, silver iodobromide, etc. , silver chloroiodide and mixtures thereof.
Moreover, they can be subjected to chemical sensitization and spectral sensitization, which are commonly performed. The binder of the photosensitive layer is usually a polymeric substance used in the production of silver halide emulsions, such as lime-treated gelatin, acid-treated gelatin, phthalated gelatin, acylated gelatin, phenylcarbamylated gelatin, polyvinyl alcohol, or saponified polyvinyl alcohol,
Polyacrylamide, polyN-vinylpyrrolidone, hydroxyethyl cellulose, carboxymethyl cellulose, heat-processed products of polyvinyl alcohol and maleic anhydride copolymers (e.g., styrene-maleic anhydride, ethylene-maleic anhydride, etc.), emulsion polymerized Synthetic resins (for example, single or copolymers of polyacrylic ester, polymethacrylic ester, acrylic acid, methacrylic acid, polystyrene, polybutadiene, etc.)
etc. can be used. Further, the photosensitive layer can be hardened using a suitable hardening agent as described in the image-receiving layer. Furthermore, the photosensitive layer contains additives generally used in silver halide photosensitive materials, such as surfactants, antifoggants, matting agents, fluorescent dyes, and developing agents (e.g., hydroquinone and its derivatives, 1-phenyl-3-pyrazolidone). and its derivatives). Furthermore, an overlayer (for example, an overlayer using lime-treated gelatin, acid-treated gelatin, hydroxyethyl cellulose, carboxymethyl cellulose, bullulan, sodium alginate, etc.) may be provided on the photosensitive layer, and an antihalation layer may be provided below. . The treatment liquid for silver complex diffusion transfer in the present invention can have a composition of a usual silver complex diffusion transfer treatment liquid. That is, developing agents for developing exposed silver halide, such as hydroquinone and its derivatives, 1-phenyl-3-pyrazolidone and its derivatives, solvents for undeveloped silver halide, such as sodium thiosulfate, ammonium thiosulfate,
Sodium thiocyanate, potassium thiocyanate, etc.
It may contain additives such as sodium sulfite as a preservative, potassium bromide as a development inhibitor, and 1-phenyl-5-mercapto-tetrazole as a toning agent. Example 1 The back side of paper with a thickness of 110 μm was coated with 25 μm polyethylene, and then, immediately after extruding polyethylene uniformly to a thickness of 25 μm on the front surface, a metal roll with a rough surface pattern engraved was crimped. , fine mats were formed on the polyethylene surface. When this was measured with a surface roughness meter, the average depth was 7 μm and the average size was 50 μm. After corona discharge machining is performed on this rough surface, the following coating liquid is applied with moisture at a rate of 40 g per square meter and dried. Gelatin 20g Water 300ml Nickel sulfide colloid solution (5mM/) 40ml 1-phenyl-5-mercapto-tetrazole (1% methyl alcohol solution) 10ml 2,4-dichloro-6-hydroxy-S-triazine sodium salt (5% aqueous solution) 4ml Sodium dodecylbenzenesulfonate (5ml)
% aqueous solution) 10ml silica (average particle size 7μm) 0.2g to pH 6 (total 400g) For drying, set it to cool for 10 seconds after application, then pass through a drying zone where the temperature gradually rises to approximately 80%
When the water evaporates, the maximum dry bulb temperature is 40°C, and the surface wet bulb temperature is 18°C (sample A), 21°C (sample B), and 23°C.
Drying was completed under the conditions of (sample C) and 25°C (sample D). Similarly, samples were also prepared in which drying was completed under conditions of a maximum dry bulb temperature of 52°C and a surface wet bulb temperature of 21°C (sample E) and 25°C (sample F). The photosensitive material is a polyethylene laminate paper with an undercoat layer containing carbon black for antihalation, and ortho-sensitized silver chlorobromide (silver bromide 5 mol %) with an average particle size of 0.35μ is coated on top of the undercoat layer containing carbon black to prevent halation. A gelatin silver halide emulsion layer containing 1.5 g/m ² in terms of nitrate, 0.2 g/m ² of 1-phenyl-3-pyrazolidone, 0.7 g/m ² of hydroquinone, and 4 g/m ² of gelatin was provided. Manufactured by The silver halide emulsion layer is hardened by containing a hardening agent so as not to interfere with diffusion transfer processing. A diffusion transfer treatment solution having the following composition was used. Water 800ml Sodium hydroxide 25g Anhydrous sodium sulfite 100g Hydroquinone 20g 1-phenyl-3-pyrazolidone 1g Potassium bromide 3g Sodium thiosulfate 30g 1-phenyl-5-mercapto-tetrazole 0.1g Add water to make 1000ml. The light-sensitive material produced as described above is exposed to appropriate light using a plate-making camera using an original with a moderate amount of black, the emulsion surface of the light-sensitive material is overlapped with the image-receiving surface of the image-receiving material, and the aperture roller containing the above-mentioned diffusion transfer processing liquid is applied. Both materials were peeled off 30 seconds after exiting the squeezing roller. The image-receiving material was washed with water for about 30 seconds, dried, and the reflection density of the black area was measured using Macbeth RD519.
Measured with a reflection densitometer.

[Table] From the results in Table 1, it is understood that the silver image density of the image-receiving layer of the rough-surfaced support increases significantly when the surface wet bulb temperature is 23°C or higher. Reference Example Samples A to F of Example 1 were produced in exactly the same manner except that smooth polyethylene-coated paper was used instead of the support, and the test results were shown in Table 2. It is shown in

Table 2 shows that the silver image density of the image-receiving layer of the smooth support gradually decreases as the surface wet bulb temperature increases. Example 2 The method of Example 1 was followed except that the following coating liquid for forming an image-receiving layer was used. Gelatin 18g Water 250ml Heat-processed product of 10% solution of polyvinyl alcohol and ethylene/maleic anhydride copolymer (described in Published Patent Application No. 1983-9646) 20g Silver sulfide colloidal liquid (5mM/) 40ml 1-phenyl-5- Mercapto-tetrazole 10ml (1% methyl alcohol solution) Formalin (5% aqueous solution) 8ml Sodium lauryl sulfate (5% aqueous solution) 10ml Adjust the pH to 5.5. (Total 400g) The results are shown in Table-3.

Table Example 3 Example 1 was repeated. However, the water content of the image-receiving layer is approximately
When 60% of the sample had evaporated, the surface wet bulb temperature was raised to 23°C or higher to complete drying. Approximately 60% of the water was evaporated at a surface wet bulb temperature below 22°C. Similar results as in Example 1 were obtained.

Claims (1)

[Claims] 1. In a method for producing an image-receiving material in which a coating solution for forming an image-receiving layer containing at least gelatin and physical development nuclei is applied to a rough-surfaced support and dried, the gelatin concentration in the image-receiving layer reaches approximately 30% by weight at the latest. A method for producing an image-receiving material, which comprises drying by raising the surface wet bulb temperature to 23°C or higher.