JPH0215052B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to an image receiving element placed in a stacked relationship with a heat-developable photosensitive element at least during thermal transfer, comprising:
The present invention relates to a thermal development method using an image-receiving element to which a thermal transfer dye released or formed by thermal development from a thermal transferable dye-providing substance contained in a photographic constituent layer of the photosensitive element is thermally transferred. Specifically, the present invention relates to a thermal development method using a thermal transfer image receiving element that can obtain a sufficiently high maximum density while suppressing the occurrence of fog, and can suppress the occurrence of so-called step unevenness. [Prior Art] The conventionally known color photography method using photosensitive silver halide is superior to other color photography methods in terms of photosensitivity, tonality, image preservation, etc., and is the most widely used color photography method. has been transformed into However, in this method, wet processing is used for steps such as development, bleaching, fixing, and water washing, which takes time and effort, and there are concerns that the processing chemicals may cause pollution to the human body, or the processing room and There are many problems, such as concerns about contamination of workers by treatment chemicals, and furthermore, the labor and cost of waste liquid treatment. Therefore, there has been a demand for the development of a method for forming color images that allows dry processing. Heat-developable black-and-white photosensitive materials characterized in that the development process is carried out by heat treatment have been known for a long time, and are described in, for example, Japanese Patent Publications No. 43-4921 and No. 43-4924. A photosensitive material comprising silver halide and a developer is disclosed. Furthermore, many heat-developable color photosensitive materials are also known, which are based on this heat-developable black-and-white photosensitive material. For example, US Patent No. 3531286, US Patent No. 3761270, US Patent No.
No. 3764328, Research Disclosure No.
No. 15108, No. 15127, No. 12044, No. 16479, etc. are U.S. patents for heat-developable photosensitive materials containing photographic couplers and color developing agents.
No. 3180731, Research Disclosure No. 13443
and No. 14347, etc., regarding those using leuco dyes, U.S. Patent No. 4235957, Research
Disclosure No.14433, No.14448, No.
15227, No. 15776, No. 18137, and No. 19419, etc., which apply the silver dye bleaching method, include U.S. Patent Nos. 4124398, 4124387, and
No. 4123273 describes methods for thermally bleaching photothermographic materials. However, these proposals regarding heat-developable color photosensitive materials are difficult or impossible to bleach or fix the simultaneously formed black, white, and silver images, or even if it is possible, wet processing etc. are not required. It is what you need. Therefore, these proposals are not found to be desirable, as it is difficult to obtain clear color images, and complicated post-processing is required. On the other hand, heat-developable color photosensitive materials that obtain color images by transferring diffusible dyes released by heat development are disclosed in JP-A-57-179840, JP-A-57-186744, and JP-A-57.
-No. 198458, No. 57-207250, No. 58-40551,
58-58543, and patent application No. 57-122596 (Japanese Unexamined Patent Publication No. 59-1989) filed by the present inventors.
No. 12431), No. 57-229649 (Unexamined Japanese Patent Publication No. 59-124338)
No.) It is also indicated in each specification etc. In these proposals, a dye-providing substance having a diffusible dye in the same molecule releases the diffusible dye through a heat development reaction of an organic silver salt, and transfers the diffusible dye to an image-receiving layer to obtain a color image. In this specification, this is referred to as a "dye-releasing type." On the other hand, patent application No. 57-229671 by the present inventors
No. 58-33363 and No. 58-33364, the proposal is that a colorless or light-colored dye-providing substance reacts with an oxidized color developing agent produced by a thermal development reaction of an organic silver salt. A color image is obtained by forming a heat-diffusible dye and transferring it to an image-receiving layer.
It is called. However, in both the dye-releasing type and the dye-forming type, fog occurs when trying to obtain a sufficiently high maximum density, and when fog is suppressed, only a low maximum density can be obtained, which is still insufficient for practical use. It is. Further, at least during thermal transfer, a photosensitive element having a photographic constituent layer containing a dye-providing substance and an image receiving element are placed in a stacked relationship and heated externally. and a reversing path for heating the entire stack of photographic materials through a reversing path formed by a rotating drum and a heating element having a semicircular cross section disposed along a side portion of the rotating drum. When using a conveyance heating type thermal transfer device (for example, see 3M's Deiberotsu Permodule Model 277, etc.), the so-called step unevenness phenomenon occurs in which the dye image obtained on the image-receiving element appears as step-like unevenness. may occur. Therefore, it is desired to develop a thermal transfer technique that can obtain a sufficiently high maximum density while suppressing the occurrence of fog, and can also suppress the occurrence of so-called step unevenness. As a result of continuing research into this technical problem, the inventors of the present invention have found that in both the dye-releasing type and the dye-forming type, color images are obtained by thermal diffusion and transfer and dyeing to the image-receiving layer. It has been found that the characteristics of the elements greatly control the quality of the resulting color images. Furthermore, it has been found that the characteristics of the image receiving element have a large influence on the occurrence or degree of occurrence of so-called step unevenness, which is likely to occur when performing thermal transfer using a thermal transfer device of a reversal path conveyance/heating type, for example. However, in the conventional techniques related to dye-releasing or dye-forming heat-developable color photographic materials, most of the means to suppress fog and obtain high-density color images are based on improvements in photosensitive elements containing dye-providing substances. In particular, as far as the present inventors are aware, there are no documents describing so-called means for solving unevenness in rows. That is, for example, the above-mentioned Japanese Patent Application Laid-open No. 57-
Publication No. 207250 proposes a so-called support/image-receiving element system in which the support of a heat-developable color photographic material is capable of receiving an image of a dye. It states that by using this method, it is possible to form a clear image in which only the dye penetrates into the support, and also states that a layer made of this dye-receptive organic polymer substance may be provided on a support such as glass. However, there is no mention at all of the suppression of so-called uneven rows. The publication lists a wide range of heat-resistant organic polymeric substances with glass transition temperatures of 40°C or higher and 250°C or lower as examples of dye-receptive organic polymeric substances, and lists particularly useful supports. Examples of materials include cellulose acetate films such as triacetate and diacetate, polyamide films made from combinations of heptamethylene diamine and terephthalic acid, fluorene propylamine and adipic acid, hexamethylene diamine and diphenic acid, hexamethylene diamine and isophthalic acid, and diethylene glycol. and diphenylcarboxylic acid, bis-p-carboxyphenoxybutane, ethylene glycol, and other combinations of polyester films, polyethylene terephthalate films, and polycarbonate films. However, even with these specific examples listed as particularly useful supports, it is difficult to obtain high-density color images while suppressing the occurrence of fog and/or to suppress so-called step unevenness. of,
The present inventors learned this as a result of various experiments. [Object of the Invention] Therefore, the object of the present invention is to be able to suppress the occurrence of so-called step unevenness, which would need to be solved in practical use, and to achieve a high maximum density while suppressing the occurrence of fog. It is an object of the present invention to provide a thermal development method using an image receiving element for thermal transfer which provides the following. [Summary of the Invention] In order to achieve the above object, the present inventors continued intensive research and found that an azomethine dye or an indoaniline dye formed by coupling with an oxidized color developing agent through thermal development was developed at 150°C for 30°C. This object is achieved by a heat development method characterized by having a step of transferring to an image receiving layer containing a vinyl chloride polymer provided on a support whose expansion/contraction rate is within ±5% when heated for a second. I found out that it can be done. That is, in the form of an image-receiving element having an image-receiving layer made of an organic polymer substance on a support,
It has been discovered that the objects of the present invention can be achieved by selecting a specific support and an image-receiving layer made of a specific organic polymer material. As is clear from the description in the above-mentioned patent publication, vinyl chloride polymers have a glass transition temperature of 40°C or higher,
Although it is one of the examples of heat-resistant polymer materials below 250°C, it is not listed as a particularly useful example at present.The vinyl chloride polymer is used as an image-receiving layer and heated at 150°C for 30 seconds. The expansion/contraction rate is ±
It was surprising that the objects of the present invention were achieved by coating or laminating on a support of up to 5%. [Structure of the Invention] The present invention will be described below. The support used in the present invention is a material whose expansion/contraction rate is within ±5% when heated at 150° C. for 30 seconds.
The test method for the expansion/contraction rate of the support is as follows. An electric iron type heat block with a smooth bottom (square shape) measuring 15 cm in length and width and weighing 1 kg was used.
The heat block was heated to 150°C, and heated at 25°C for 30 seconds on a square support (test piece) of 10 cm in length and width placed on a flat table. Heating is called "constant heating").
The constant heated support is left at a temperature of 25°C for 10 minutes, and the support according to the present invention has both vertical and horizontal lengths within ±5% of the initial vertical and horizontal lengths of 10 cm. This is the support used. In other words, if the support, which was 10 cm in length and width, is heat-shrinked in the measurement after being heated to the above-described constant temperature and left to stand, the heat shrinkage rate is within 5%, that is, 9.5 cm in both length and width. On the other hand, in the case of hot stretching, the hot stretching ratio is within 5%, that is, 10.5 cm or less in both length and width. Specific examples of the support used in the present invention include:
For example, paper, photographic baryta paper, ivory paper, capacitor paper, polycarbonate film, polyether sulfone film, polyimide film,
Examples include cellulose ester film, acetylcellulose film, polyvinyl acetal film, and polyethylene terephthalate film (preferably polyethylene terephthalate film with a crystallinity of 40% or more). As a specific example of the support used in the present invention, in addition to having a thermal expansion/contraction rate of the present invention, it is also possible to use it in a wide range of thermal transfer devices, and it is particularly suitable for reverse path conveyance. This is preferable because it can also be suitably used in a heating type thermal transfer device. However, the use of the image receiving element of the present invention is not limited to use in such a specific thermal transfer device. However, this does not preclude the use of heat-resistant organic polymeric substances or inorganic substances that have no or poor flexibility due to the heat resistance. Note that there is no particular restriction on the thickness of the support used in the present invention, but so that it can be suitably used in a reverse path conveyance heating type thermal transfer device, etc.
For example, when using a film such as polyethylene terephthalate film with a crystallinity of 40% or more, 5μm
~500 μm, preferably 15 μm to 300 μm. In the image-receiving element of the present invention (an image-receiving element comprising an image-receiving layer containing a vinyl chloride polymer on a support whose expansion/contraction rate is within ±5% when heated at 150° C. for 30 seconds as described above; the same applies hereinafter) The image receiving layer includes a vinyl chloride polymer. The vinyl chloride polymer used in the present invention is produced by polymerizing vinyl chloride by suspension polymerization, bulk polymerization, or emulsion polymerization by irradiation with light or alpha rays, or in the presence of a free radical polymerization catalyst such as peroxide. , a homogeneous solution polymerization method, a precipitation solution polymerization method, etc. The polymer of the present invention may be polyvinyl chloride, which is a homopolymer of vinyl chloride, or may contain other monomers such as vinyl acetate, vinyl propionate, coconut acid, etc., if it contains 50 mol% or more of vinyl chloride. Alkyl esters of unsaturated fatty acids such as vinyl and vinyl tallow, acrylic acid, methacrylic acid, methyl acrylate, ethyl methacrylate, butyl acrylate, 2-hydroxyethyl methacrylate, 2-acrylic acid
Acrylic acid or methacrylic acid and its alkyl esters such as ethylhexyl, maleic acid and its alkyl esters such as maleic acid, diethyl maleate, dibutyl maleate, dioctyl maleate, methyl vinyl ether, 2-ethylhexyl vinyl ether, lauryl vinyl ether, palmityl vinyl ether,
Alkyl vinyl ethers such as stearyl vinyl ether, vinylidene chloride, ethylene, propylene, acrylonitrile, methacrylonitrile, styrene, chlorostyrene, itaconic acid and its alkyl esters, crotonic acid and its alkyl esters, dichloroethylene, trifluoroethylene, etc. It may also be a copolymer (including a graft copolymer) with polyhalogenated olefins, cycloolefins such as cyclopentene, aconitate esters, vinyl benzoate, benzoyl vinyl ether, and the like.
The degree of polymerization of vinyl chloride polymers is standardized in the range of 275 to 2460 in JIS K 6721, but in the present invention, both homopolymers and copolymers can be used regardless of the degree of polymerization. The image-receiving layer of the present invention may contain various additives, and for example, a plasticizer is preferably added to impart plasticity. Examples of plasticizers include phthalate esters (e.g. dimethyl phthalate, dibutyl phthalate, dioctyl phthalate, didecyl phthalate, etc.), adipate esters (dioctyl adipate, methyl lauryl adipate, di-2-ethylhexyl adipate). , ethyl lauryl adipate, etc.), other oleic acid esters,
Succinic acid esters, maleic acid esters, sebacic acid esters, citric acid esters, epoxy stearic acid esters, phosphoric acid esters such as triphenyl phosphate and tricresyl phosphate, ethyl phthalyl ethyl glycolate,
There are glycol esters such as butylphthalyl butyl glycolate. In the thermal transfer image-receiving element of the present invention, addition of a plasticizer not only imparts plasticity but also contributes to improving dye transfer efficiency and light resistance of transferred images. The amount of plasticizer added varies depending on the type of plasticizer, but is usually 0.1% to 50% by weight, preferably 0.5% by weight based on the vinyl chloride polymer.
%~45%. A stabilizer is preferably added to the image-receiving layer of the present invention in order to prevent decomposition and modification of the vinyl chloride polymer due to dehydrochlorination. Stabilizers include metal compounds (e.g. stearates of lead, zinc, barium, calcium, etc.), organic tin compounds (e.g. dibutyltin diisooctyl maleate, dibutyltin dilaurate, dibutyltin nonylthioglycolate, dibutyltin lauryl mer). captide, dioctyltin maleate, etc.). The image-receiving layer of the present invention may be mixed with other polymers to form a so-called polymer blend in order to increase its physical strength and heat resistance. Reinforcing agents to increase physical strength include chlorinated polyethylene, ethylene-vinyl acetate copolymer, polybutadiene, neoprene, isobutylene polymer, isoprene polymer, methyl methacrylate-butadiene-styrene copolymer, acrylonitrile-butadiene,
Examples include styrene copolymer, acrylonitrile-butadiene copolymer, and styrene-butadiene copolymer. To improve heat resistance, α
- Polymers containing methylstyrene, vinylcarbazole, and acenaphthylene are effective. In particular, vinyl chloride polymers containing poly-α-methylstyrene have a small thermal shrinkage rate and excellent dimensional stability. Furthermore, a polymer having excellent dye retention properties such as polyvinylpyrrolidone, polyvinyl butyral, and saturated polyester may be added to the image-receiving layer of the present invention. These other polymers are used in up to 50% by volume of the image receiving layer. A lubricant (slip agent) may be added to the image-receiving layer of the present invention in order to increase manufacturing and processing efficiency and improve quality, and to peel off the image-receiving layer and the photosensitive element or photosensitive layer after thermal transfer. It is valid. Examples of lubricants include hydrocarbons such as liquid paraffin and low-molecular polyethylene, aliphatic alcohols such as stearyl alcohol and cetyl alcohol, aliphatic ketones such as stearone and palmitone, fatty acids such as stearic acid and lauric acid,
Fatty acid amides such as stearic acid amide, oleic acid amide, methylene stearobisamide, waxes such as cetyl palmitate, polyalcohol esters such as diethylene glycol monooleate, and chlorinated naphthalene, chlorinated diphenyl, and fluorine resins. , silicone oil, silicone resin, and finely divided silicic anhydride. The image-receiving layer of the present invention preferably contains an antistatic agent. Usual anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants are used. In addition to the above, the thermal transfer image receiving element of the present invention includes:
Antioxidants, ultraviolet absorbers, dyes, pigments, etc. can also be added. The method of manufacturing the image receiving element of the present invention is arbitrary. For example, it can be produced by coating the support of the present invention with an image-receiving layer containing a vinyl chloride polymer or by laminating it. In addition to this, a method may be adopted in which the coating liquid constituting the support of the present invention is applied or vapor-deposited onto the vinyl chloride polymer film or sheet constituting the image-receiving layer of the present invention. . However, in view of cost, the coating method and the laminating method are advantageous, and the vinyl chloride polymer constituting the image-receiving layer of the present invention or a coating liquid containing the polymer as a main component is coated on the support. For example, a solution using tetrahydrofuran, methyl ethyl ketone, toluene, xylene, chloroform, dioxane, acetone, etc. as a solvent may be used, or a vinyl chloride polymer may be prepared by emulsion polymerization, preferably an aqueous dispersion. For coating on the support, commonly used methods can be applied, such as dip method (immersion method), roller method, reverse roll method,
Examples include the air knife method, doctor blade method, spray method, extrusion method, bead method, stretch flow method, and curtain method. On the other hand, in order to laminate a vinyl chloride polymer or a film or sheet containing the polymer as a main component on the support, a previously formed film or sheet is stacked on the support and heat sealing or high frequency welding is performed. , laminating methods such as ultrasonic welding are used. The amount of the image-receiving layer containing the vinyl chloride polymer coated or laminated on the support is 1 g/m ² to 500 g/m ² , preferably 5 g/m ² to 300 g/m ² . In the thermal transfer image-receiving element of the present invention, a white pigment may be added to the support or a white reflective layer may be provided in order to view a reflected image. White pigments include titanium white, magnesium carbonate, zinc oxide, barium sulfate, silica, talc,
Clay, calcium carbonate, etc. Further, in order to provide a light-shielding effect to the photosensitive layer, a black pigment may be added to the support, or a light-shielding layer may be provided. Examples of black pigments include carbon black, manganese dioxide, and graphite. As described above, the image-receiving element of the present invention may have one or more photographic constituent layers other than the image-receiving layer of the present invention. The relationship between the image-receiving element of the present invention and the photosensitive element layer used in combination with the image-receiving element may be in any conventionally known form. (2) The image-receiving element of the present invention is placed in a stacked relationship with respect to the photographic constituent layers of the photosensitive element during thermal transfer after thermal development. (3) The image-receiving element of the present invention is integrally provided on the photographic constituent layer of the photosensitive element, and imagewise exposure and thermal development are performed through the image-receiving element. It can be any of the following, or
[] The image-receiving element of the present invention may be of a type that is peeled off after thermal transfer, or [] The image-receiving element of the present invention may be of a type that is not peeled off after thermal transfer. In the present invention, thermal transfer means that the dye is sublimated, vaporized, evaporated, melted by heat, or dissolved by a solvent, and then diffused and transferred. The image-receiving element for thermal transfer of the present invention can be applied to either the dye-releasing type or dye-forming type heat-developable photosensitive element. Therefore, it shows excellent suitability for thermal transfer and dyeing of azomethine dyes or indoaniline dyes formed by coupling with oxidized products of color developing agents. Preferred examples of such dyes are disclosed in the aforementioned Japanese Patent Application Nos. 57-229671 and 58-33363 by the present inventors.
No. 58-33364. For the thermal transfer image-receiving element of the present invention, thermal transfer is performed when the photothermographic element is thermally developed or when it is reheated after thermal development. For heating for thermal transfer, all methods applicable to ordinary heat-developable photographic materials can be used. For example, by contacting with a heated block or plate, by contacting with a heated roller or drum, by passing through a high temperature atmosphere, by using high frequency heating, and furthermore, by contacting with a heated block or plate, by passing through a high temperature atmosphere, by using high frequency heating, and furthermore, by contacting with a heated block or plate, by contacting with a heated block or plate, by passing through a high-temperature atmosphere, by using high frequency heating, and furthermore, in a heat-developable photosensitive element or the present invention. It is also possible to provide an electrically conductive layer in the image receiving element for thermal transfer and utilize Joule heat generated by electricity or a strong magnetic field. There are no particular restrictions on the heating pattern; after preheating,
Although methods such as reheating, continuously rising, falling, or repeating heating at high temperature for a short time, or at low temperature for a long time, and even discontinuous heating are also possible, a simple pattern is preferable. Usually, the heating temperature during transfer is 80℃~200℃, preferably 80℃~160℃
℃, and the heating time is usually in the range of 1 second to 1 minute, preferably 1 second to 40 seconds. Thermal transfer using the image receiving element for thermal transfer of the present invention is
It is easy to use a commercially available heat developing machine. For example, “Image forming type 4634” (Sony
Tektronix), “Deiberotsu Permodule”
277” (3M), “Video Hard Copy Unit
NWZ-301'' (Japan Radio Co., Ltd.), etc. [Example] The present invention will be illustrated below with reference to Examples. Example 1 7.45 g of 4-sulfobenzotriazole silver was Add W-201, 24 ml of 8% aqueous solution, 1.3 g of ossein gelatin, 110 ml of water, and 25 ml of methanol.
Dispersion was performed using an alumina ball mill to obtain a silver salt dispersion. To 25 ml of this silver salt dispersion, 0.21 g of phthalic acid, 0.16 g of phthalazine, 0.44 g of the following compound X-1, 0.42 g of the following developing agent Dev-1, 1.8 g of 1,3-dimethylurea, and water-soluble polyvinyl alcohol (105, Kuraray) 5 ml of 8% aqueous solution, 10 ml of water, and a silver iodide emulsion with an average grain size of 0.04 μm converted to silver.
36mg was added, and the wet film thickness on photographic baryta paper was
A photosensitive element having a photosensitive layer was obtained by coating with a wire bar to a thickness of 55 μm. For the heat-developable photosensitive element sample obtained by drying,
An exposure of 30,000 CMS was given through the step wedge. On the other hand, as the image receiving element for thermal transfer of the present invention, the thickness
An image receiving element having an image receiving layer was obtained by coating a 10% tetrahydrofuran solution of polyvinyl chloride (Altron, Mitsubishi Monsanto) with a wet film thickness of 120 μm on a transparent polyethylene terephthalate film of 100 μm, crystallinity 45.5%, and density 1.387. Ta. The exposed sample and the image receiving element for thermal transfer (each sample 10 cm in length and width) were stacked and subjected to constant heating according to the present invention, that is, compression heating for 30 seconds using an electric iron type heat block with a surface temperature of 150°C. I tore it off. A step wedge image with a maximum reflection density of 1.45 and a minimum reflection density of 0.06 at 642 nm was obtained on the surface of the image receiving element of the present invention. Further, the thermal shrinkage rate of the image receiving element of the present invention at this time is:
It was 1.6%. Example 2 Samples of photosensitive elements were prepared in the same manner as in Example 1, but instead of photographic baryta paper, they were coated with acrylic acid ester polymer latex.
100μm transparent polyimide film (KAPTON,
(manufactured by DuPont) was used as a support. On the other hand, as an image receiving element for thermal transfer, a thickness of 50 μm,
On a transparent polyethylene terephthalate film with a crystallinity of 53.8% and a density of 1.397, a polyvinyl chloride solution was applied under the same conditions as in Example 1 to form an image-receiving layer, and on top of that, a white reflective layer with the following composition was formed. Established. <White reflective layer> (Unit: g/m ² ) Titanium dioxide (average particle size 1.5 μm) 12 Eslec W-201 (Sekisui Chemical Co., Ltd.) 1.3 The above-mentioned photothermographic element and image receiving element for thermal transfer (each sample 10 cm in length and width) were superimposed and fixed, and exposure of 30,000 CMS was applied from the polyimide film support side through a step wedge with a step height of 0.15, and the constant heating of the present invention was performed in the same manner as in Example 1. The polyethylene terephthalate film side of the image receiving element of the present invention has a maximum density at 642 nm.
1.38, a negative image of the step wedge with a minimum density of 0.05 was obtained. Further, the thermal shrinkage rate of this image receiving element for thermal transfer was 1% or less. Example 3 The heat-developable photosensitive element used in Example 1 was used, and the image receiving element shown in Table 1 below was used. The film was fixed and processed for 30 seconds at a heating temperature of 150° C. using a Deiberot Per Module 277 thermal transfer device (manufactured by 3M). After the treatment, it was immediately peeled off, the maximum reflection density and minimum reflection density at 642 nm were measured, and the occurrence of so-called step unevenness was visually judged. In addition, 〇 mark indicates that unevenness does not occur, △ mark indicates that unevenness occurs slightly,
A three-step method was used in which the most number of X marks occurred. The results are shown in Table-2.

【table】

【table】

[Table] As is clear from the results in Table 2, only the sample of the present invention (No. 13) was able to obtain high-density images while suppressing the occurrence of fog, and was also able to suppress the occurrence of unevenness. I understand.

Claims (1)

[Claims] 1. An azomethine dye or an indoaniline dye formed by coupling with an oxidized form of a color developing agent by heat development is provided on a support whose expansion/contraction rate is within ±5% when heated at 150°C for 30 seconds.
A heat development method comprising the step of transferring to an image-receiving layer containing a vinyl chloride polymer.