JPH0356919B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a recording medium suitable for printing high-resolution characters or images, particularly a color discharge transfer recording medium. (Prior Art) In recent years, with the development of office automation, various types of terminal devices have been required. Among them, there is a large demand for recording devices that convert electrical signals into visible images, so-called printers, but none of them are satisfactory in terms of performance. There's not much to go on. For example, commonly used recording methods include the inkjet method, electrophotographic method, and thermal transfer method. Since a head is used, there are problems such as a short head life and slow printing speed. Therefore, the discharge transfer method is known as a means for forming characters or images at high speed and with relatively good resolution.
In this regard, for example, the thermograph copying method disclosed in Japanese Patent Publication No. 19819/1981, Japanese Patent Publication No. 57/22030
The transfer medium of the publication is disclosed. The conventional discharge transfer method will be explained below with reference to the drawings. FIG. 2 is a cross-sectional view of a transfer medium used in this method, in which a light reflecting layer 2 is provided on the upper surface of a support 1, a light-to-heat conversion layer 3 is provided on the lower surface, and a thermally transferable solid ink layer 4 is provided on the lower surface of the light-to-heat conversion layer 3. There is. Although not shown, if a roughened layer is provided between the support 1 and the reflective layer 2, the light reflective layer can be more easily destroyed by discharge and stabilized. 3 to 5 show the printing process using the recording medium, and the same parts as in FIG. 2 are given the same reference numerals. 5 is a receiving paper, 6 is a xenon lamp, and 7 is a flash. In the printing process, as shown in FIG. 3, the light reflecting layer 2 is removed according to the information pattern by a well-known discharge breakdown recording method, and as shown in FIG. paper 5
are brought into close contact with each other, and a xenon flash lamp 6 is used to irradiate the entire surface with flash light containing ultraviolet rays, visible rays, and infrared rays from above the light reflecting layer 2. Then, the flash of light irradiated on the part where the light reflection layer 2 remains is reflected, and the flash of light irradiated on the part from which the light reflection layer has been removed passes through the support 1 and reaches the photothermal conversion layer. The photothermal conversion layer absorbs flash energy and effectively converts it into thermal energy. At this time, the thermally transferable solid ink layered on the photothermal conversion layer is thermally melted or thermally sublimated by thermal energy, and as a result is transferred onto the sealed image receiving paper.
It is fixed, and a transferred image 8 can be obtained. (Problems to be Solved by the Invention) However, in the structure in which the conventional discharge breakdown recording sheet and the heat transferable solid ink sheet are directly integrated as described above, when an image receiving paper with a high surface smoothness is used, Although it is relatively clear and has the desired density, and can almost faithfully transfer the pattern created by discharge breakdown recording, it cannot be used with plain paper such as copy paper or bond paper used as business paper in Europe and the United States. When using image-receiving paper with a low surface smoothness such as There are problems in that during transfer, areas that are not transferred, called ``chips'' and ``stains'', tend to appear, and thin lines ``togire'' and ``fading'' tend to occur. In addition, in order to improve the transfer recording quality, it is possible to lower the melting point and melt viscosity of the heat-melting binder, or to lower the sublimation start temperature of the heat-sublimable paint, but in this case, the "bridging phenomenon" may occur. As a result, unresolved transfer (called "unresolved transfer") occurs, and transfer tends to occur even at relatively low temperatures, other problems arise, such as reduced storage stability and fogging in non-recorded areas. . Furthermore, the greatest feature of the discharge transfer method is that high-resolution characters and images can be faithfully and clearly transferred by discharge recording, but in the conventional configuration mentioned above, the edges of the transferred image "Bridging" and "Bokeh"
There was a problem in that prints were often thickened due to the printing process, and as a result, they tended to have a so-called "sharp" quality that lacked contrast and sharpness. Furthermore, regarding the gradation expression of each primary color required when obtaining a full-color transferred image using the discharge transfer method, in the conventional configuration, the gradation expression obtained by discharge breakdown recording is not possible. There is a problem that it is difficult to transcribe faithfully. That is, in a discharge breakdown recording pattern expressing areal gradation using the dither method, etc., the area irradiated with flash energy absorbed by the ink layer or the photothermal conversion layer can be controlled in accordance with the recording dot density, but it is not sufficient. In order to obtain gradation, it is difficult to maintain resolution during transfer, and the transfer recording density tends to saturate to a constant value, making it difficult to express gradation with high dot density. (Means for Solving the Problems) In view of the above-mentioned circumstances, the present invention has been made as a result of intensive studies to solve the problems, and the outline thereof is as follows. A light-reflecting layer removable by discharge destruction recording is provided on one side of a light-transmitting support, and an intermediate intervening layer (hereinafter referred to as intermediate layer) containing a photodegradable compound consisting of a diazo compound or an azide compound is provided on the other side of the support. A photothermal conversion layer (hereinafter referred to as photothermal conversion layer) containing at least one photothermal conversion substance selected from inorganic pigments, organic pigments, dyes, ultraviolet absorbers, or infrared absorbers (hereinafter referred to as photothermal conversion layer) and a thermally transferable solid ink layer are sequentially formed. This is a discharge recording medium characterized by: (Function) A typical structure according to the present invention is as shown in FIG. 1, and as is clear from comparison with the structure according to the conventional technology, the intermediate layer 9 containing a photodegradable compound made of a diazo compound or an azide compound is It is provided. Other parts that are the same as those in FIG. 2 are designated by the same reference numerals, so their explanation will be omitted. According to the studies conducted by the present inventors, it can be assumed that a typical process of the discharge transfer method is performed in the following order. A flash of light is irradiated from above the light reflective layer. A flash of light is incident on the discharge-destructive recording surface, and is reflected from the non-destructive recording surface, that is, the light-reflecting layer surface. The light incident on the discharge breakdown recording surface is absorbed by the photodegradable compound made of a diazo compound or an azide compound in the intermediate layer containing the photodegradable compound made of a diazo compound or an azide compound. Photodecomposition of a photodecomposable compound consisting of a diazo compound or an azide compound and generation of gas accompanying this The light transmitted through the intermediate layer is absorbed by the photothermal conversion layer and converted into thermal energy. Heat conduction of thermal energy to the thermally transferable solid ink layer Increase in temperature of the solid ink layer and reaching melting temperature or sublimation start temperature Absorption of heat of fusion or sublimation of the solid ink layer Start of thermal melting or sublimation of the solid ink layer Image reception Penetration of heat-fusible solid ink or adhesion of heat-sublimable coloring material to the paper surface Heat dissipation of heat of solidification or sublimation of solid ink to the support side or receiving paper side Support as the ink layer temperature falls to room temperature Dissipation of heat to the body side or image receiving paper side When the medium and image receiving paper are separated, the image receiving paper/image receiving paper side
Transfer of ink to image-receiving paper due to ink-to-ink adhesive force being greater than ink/medium support adhesion force Through the above steps, the transfer of the thermally transferable solid ink to the image-receiving paper is completed. The intermediate layer containing a photodegradable compound made of a diazo compound or an azide compound, which is a feature of the present invention, is considered to have the following effects on the above process. 1. Pressing and pressing the ink layer surface against the image receiving paper surface. The light-to-heat conversion layer swells due to the gas generated during the process), and the ink layer surface is pressed and pressed along the roughness of the image-receiving paper surface. Further, in processes () and (), the gas in the intermediate layer thermally expands due to the amount of heat dissipated toward the side of the support, thereby amplifying the pressing/pressing effect. Due to the pressure and contact effect caused by the gas generated in the intermediate layer, even when the contact pressure between the ink layer surface and the receiving paper surface is low, "white spots" may occur during solid transfer to receiving paper with low surface smoothness. , "chips" during fine line transfer
"Toggle" and "fading" are prevented, and high-level images and high-density transfer are possible. 2. Suppression of heat dissipation of condensation heat or sublimation heat toward the side of the support. In process),), the amount of heat that would have been dissipated toward the support in the conventional configuration is greatly suppressed from being dissipated toward the support due to the heat insulating effect of the gas generated in the intermediate layer. The adiabatic effect here takes advantage of the fact that the thermal conductivity of gas is much smaller than that of general solids. the result,
The suppressed amount of heat is accumulated in the photothermal conversion layer and the ink layer, further increasing the temperature of the ink layer. As a result, when the ink is heat-meltable, the melt viscosity decreases and the molten state retention time increases. On the other hand, in the case of thermal sublimation, the amount of sublimation of the thermal sublimable color is significantly increased. In addition, the accumulated heat causes temporary softening and elongation of the light-to-heat conversion layer and the intermediate layer, which makes it easier for the ink layer surface to adhere to the image-receiving paper surface along the roughness. Due to the heat insulation effect of the gas generated in the intermediate layer, that is, the effect of suppressing heat dissipation,
Even at low adhesion pressure, it is possible to improve the transferability as in 1) for image receiving paper with low surface smoothness. The effects listed above combine to make it possible to obtain faithful transfer recording quality with good "sharpness" without "bleeding" or "blurring" for characters and images of high order images by discharge breakdown recording, and at the same time. This significantly improves gradation expression and transfer recording quality, making it possible to apply it to full color. The properties required of the intermediate layer are as follows, but these properties are controlled by the properties of the binder forming the intermediate layer. 1. A photodegradable compound consisting of a diazo compound or an azide compound is uniformly dissolved or dispersed in the layer. 2. During light irradiation, a photodegradable compound consisting of a diazo compound or an azide compound is effectively photodecomposed, and at the same time, gas is uniformly generated. 3. It must have enough elasticity, flexibility, and stretchability to press the ink layer surface against the image-receiving paper surface as gas is generated. Next, the materials constituting the discharge transfer recording medium of the present invention will be described in detail. First, the binder material suitable for the intermediate layer in the present invention includes at least one selected from thermoplastic resins, waxes, and rubbers. As the thermoplastic resin, thermoplastic elastomers are particularly desirable, and specific examples thereof include polyethylene,
Olefin resins such as polypropylene, polybutylene, polybutadiene, acrylic resins such as polymethyl methacrylate, ethylene/ethyl acrylate copolymer, styrene resins such as polystyrene, AS resin, BS resin, ABS resin, polyvinyl chloride, Polyvinylidene chloride, polyvinyl acetate, ethylene/vinyl acetate copolymer, polyvinyl butyral, vinylidene chloride/acrylonitrile copolymer, vinyl chloride/vinyl acetate copolymer, vinyl chloride/vinylidene chloride copolymer, propylene/vinyl chloride Vinyl resins such as copolymers, nylon 6,
Polyamide resins such as nylon 66 and nylon 12, saturated polyester resins, polycarbonate resins, polyacetal resins, polyphenylene oxide resins, polyphenylene sulfide resins, polysulfone resins, polyurethane resins, tetrafluoroethylene resins, trifluoroethylene resins, polyfts Fluorine resins such as vinylidene chloride, cellulose resins such as ethyl cellulose, cellulose acetate, and nitrocellulose, organic solvent-soluble resins such as epoxy resins, ionomer resins, rosin derivative resins, gelatin, glue, casein, hydroxyethyl cellulose, and carboxymethyl cellulose. , methylulose, carboxymethyl hydroxyethyl cellulose, hydroxyethyl starch, gum arabic, sutucarose octaacetate, ammonium alginate, sodium alginate, polyvinyl alcohol, polyvinyl butyral, polyvinylpyrrolidone, polyvinylamine, polyethylene oxide, polystyrene sulfonic acid, polyacrylic acid, Examples include water-soluble resin systems such as polyamide, isobutylene/maleic anhydride copolymer, and emulsion systems of organic solvent-soluble resin systems described above. Specific examples of waxes include candelilla wax, carnauba wax, rice wax, tree wax, vegetable waxes such as jojoba oil, beeswax,
Animal-based waxes such as lanolin and spermaceti; mineral-based waxes such as montan wax, ozokerite, and ceresin; petroleum waxes such as paraffin wax, microcrystalline wax, and petrolatum;
Synthetic hydrocarbons such as fissure tropism waxes and polyethylene waxes, modified waxes such as montan wax derivatives, paraffin wax derivatives and microcrystalline wax derivatives, hydrogenated waxes such as hydrogenated castor oil and hydrogenated castor oil derivatives, 12- Examples include hydroxystearic acid, stearamide, higher alcohols, waxes of these types, and blends of waxes with organic and inorganic substances. Specific examples of rubber include natural rubber, isoprene rubber, styrene-butadiene rubber (SBR), butadiene rubber, acrylonitrile-butadiene rubber, butyl rubber, ethylene-propylene rubber, chloroprene rubber, acrylic rubber, chlorosulfonated polyethylene rubber, Examples include hydrin rubber, urethane rubber, polysulfide rubber, silicone rubber, fluorine rubber, rubbers such as these, and blends of rubber and organic/inorganic substances. These intermediate layer binders may be used alone or in combination of two or more types, but the binders are not limited to these. Next, the photodegradable compound to be added to the intermediate layer must be rapidly photodecomposed by light including ultraviolet rays, visible light, infrared rays, etc., and diazo compounds and diazo compounds are suitable materials for this purpose. Examples include azide compounds. The following items can be listed as properties required of the diazo compound and azide compound. 1. Can be uniformly dissolved or dispersed in the intermediate layer. 2. High photodecomposition rate and effective generation of nitrogen gas. 3. Must be resistant to thermal and mechanical shock. Diazo compounds with these properties include:
Those conventionally used in the field of diazo copying materials can be mentioned as they are. That is, specific examples thereof include 4-diazo-1-dimethylaminobenzene, 4-diazo-1-diethylaminobenzene, 4-diazo-1-dipropylaminobenzene, 4-diazo-1-methylbenzylaminobenzene, and 4-diazo-1-dimethylaminobenzene. Diazo-1-dibenzylaminobenzene, 4-diazo-1-ethylhydroxyethylaminobenzene, 4-diazo-1-diethylamino-3-methoxybenzene, 4-diazo-1-dimethylamino-2-methylbenzene, 4- Diazo
1-benzoylamino-2,5-diethoxybenzene, 4-diazo-1-morpholinobenzene, 4
-Diazo-1-morpholino-2,5-dimethoxybenzene, 4-diazo-1-morpholino-2,5
-diethoxybenzene, 4-diazo-1-morpholino-2,5-dibutoxybenzene, 4-diazo-1-morpholino-2,5-diisopropoxybenzene, 4-diazo-1-anilinobenzene, 4
-Diazo-1-dimethylamino-3-carboxybenzene, 4-diazo-1-tolylmercapto-2,5-diethoxybenzene, 4-diazo-
1,4-methoxybenzoylamino-2,5-diethoxybenzene, 4-diazo-1-pyrrolidino-3-methylbenzene, 4-diazo-1-pyrrolidino-2-methylbenzene, 4-diazo-1-dimethylamino -2-(4'-chlorophenoxy)-5
-Chlorobenzene, etc. can be mentioned. The above diazo compound can be stabilized by forming a double salt of its chloride and a metal halide such as zinc chloride, cadmium chloride, and tin chloride. Alternatively, the diazo compound may be stabilized by forming a complex salt with a fluoride acid such as tetrafluoroboric acid, hexafluorophosphoric acid, or fluorosulfuric acid, or an organic boron salt such as sodium tetraboronate. On the other hand, aromatic azide compounds are particularly effective as azide compounds. That is, as a specific example, In addition to the above, 4,4'-diazide-diphenylsulfone, 4,4'-diazidebenzosulfone, 4,4'-
diazidostilbene, 4,4'-diazidobenzalacetone, 2,6-di-(4-azidobenzal)-
4-Methylcyclohexanone, 4,4'-diazide diphenyl sulfide, 1,2-(4,4'-diazide diphenyl)ethane, 4,4'-diazide diphenyl ether, azidobenzoxazole ,
4,4'-diazide-diphenylmethane, 4,4'-
Examples include sodium diazidostilbene-2,2'-disulfonate, azidobenzoic acid, and azidobenzenesulfonic acid. Since these azide compounds are capable of optical sensitization, a sensitizer can be added as needed to improve the practical photosensitivity. The above diado compounds and azide compounds can be used alone or in combination of two or more types. The appropriate amount of these photodegradable compounds to be used is 0.1 to 80 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the total solid content in the intermediate layer. The intermediate layer can be formed by dispersing or dissolving a photodegradable compound in the binder described above, but for the purpose of effectively amplifying the pressing/pressing effect of nitrogen gas during photodecomposition, A thermoplastic substance may be added if necessary. The thermoplastic material in this case may be any material as long as it is compatible with the binder and the photodegradable compound, melts or softens due to thermal energy, and promotes thermal expansion of the nitrogen gas generated by photolysis. Specific examples of such include lauric acid amide,
Higher fatty acid amides such as stearic acid amide and N-behenylbenzamide, aromatic carboxylic acid amides, higher fatty acids such as lauric acid, stearic acid, and oleic acid or their esters, polyethylene glycol, polyethylene oxide, polyethylene oxide/polypropylene oxide graft copolymer Examples include merging. Furthermore, for the purpose of imparting plasticity to the intermediate layer, a phthalate-based, glycol ester-based, epoxy-based, polyester-based, vinyl polymer-based plasticizer or the like may be added, if necessary. Furthermore, for the purpose of improving the dispersion state and coating film formation state, a dispersant or a pigment may be added as necessary. An intermediate layer coating can be obtained by adding the above binder, a photodegradable compound consisting of a diazo compound or an azide compound, and various additives as necessary, and dissolving or dispersing the mixture in a suitable solvent. Dissolution or dispersion when creating the intermediate layer paint can be carried out using conventionally used planetary mixers, butterfly mixers, sand mills, tank mixers, attritors, three-roll mills,
This can be done using a vibrator mill, jet mill, etc. The intermediate layer coating material is formed on the light-transmitting support surface by a solvent coating method. Coating can be performed using an air doctor coater, blade coater, rod coater, knife coater, squeeze coater, impregnation coater, reverse roll coater, transfer roll coater, gravure coater, kiss roll coater, and the like. The thickness of the intermediate layer is suitably in the range of 0.01 to 20 μm, preferably 0.1 to 10 μm. Next, the formation of the light-to-heat conversion layer will be explained. The following items can be listed as characteristics required of the light-to-heat conversion layer. 1. The photothermal conversion substance is uniformly dissolved or dispersed. 2. Photothermal conversion materials must absorb light energy including ultraviolet rays, visible light, infrared rays, etc. over a wider wavelength range and convert it into thermal energy more effectively. 3. The interfacial adhesion between the intermediate layer and the light-to-heat conversion layer must be strong enough to not impede the pressure/pressure effect of the gas in the intermediate layer. The above characteristics are mainly controlled by the properties of the binder forming the light-to-heat conversion layer, the light-to-heat conversion substance, and the solvent. As the material for the binder constituting the light-to-heat conversion layer, generally used coating binders can be basically used, but thermoplastic resins, rubbers and thermosetting resins are particularly preferred.
Among these, thermoplastic resins and rubbers can be selected from the specific examples listed as binders for use in the intermediate layer. Specific examples of thermosetting resins include unsaturated polyester resin, epoxy resin, xylene resin, polyamide/imide resin, silicone resin, polyimide resin, polyurethane resin, olefin resin, allyl resin, melamine resin, furan resin, and urea resin. , phenolic resin, phenol-formaldehyde resin, polyester-amino resin, alkyd resin, etc. These light-to-heat conversion layer binders may be used alone or in combination.
Although it is possible to use a mixture of more than one species, the binder is not limited to these.
In addition, examples of materials for the photothermal conversion substance include inorganic and organic pigments and dyes, ultraviolet absorbers, and infrared absorbers. Specific examples include metal powders such as carbon black, graphite, iron powder, copper powder, chromium powder, and aluminum powder, and inorganic materials such as metal oxides, sulfides, selenides, ferrocyanides, chromates, and silicates. Organic pigments such as pigments, azo pigments, dyed lake pigments, nitro pigments, nitroso pigments, phthalocyanine pigments, metal complex pigments, perylene pigments, isoindolinone pigments, quinacridone pigments, nitrone dyes, nitro dyes, azo dyes, stilbene azo dyes , triphenylmethane dye, xanthene dye,
Quinoline dyes, thiazole dyes, azine dyes, oxazine dyes, sulfur dyes, anthraquinone dyes,
Dyes such as indigoid dyes and phthalocyanine dyes, salicylic acid-based, benzophenone-based, benzotriazole-based, cyanoacrylate-based, nickel-dibutyldithiocarbamate, and benzoate-based quenchers, and UV absorbers such as hindered amines; commercially available infrared absorbers (Mitsui East Made by Presssha
IR absorber-PA-1001, PA-1005, PA-
1006, Fujifilm IRF-905, IRF-700
etc.) etc. These photothermal conversion substances can be used alone or in combination of two or more types. The appropriate amount of the photothermal conversion material used is 1 to 50 parts by weight, preferably 3 to 30 parts by weight, based on 100 parts by weight of the total solid content in the intermediate layer. The solvent of the paint for forming the light-to-heat conversion layer is:
It is required to have the properties of at least a binder and a solvent for dissolving the light-to-heat conversion substance, or a dispersion medium for dispersing it. Furthermore, during coating, the properties of the photodegradable compound must not be impaired due to significant erosion of the intermediate layer. Furthermore, as will be described later, in order to coat the intermediate layer with a level of interfacial adhesion that does not impede the pressing/pressure effect of the intermediate layer, the intermediate layer must be coated with a relatively resistant solvent. system is preferable. These solvents can be selected from those commonly used for paints, and specific examples include aliphatic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, alcohols, ethers, ketones, and esters. Examples include nitriles, carbon tetrachloride, carbon disulfide, water, etc. These solvents may be used alone or as a mixed solvent of two or more, but the solvents are not limited to these. In addition to the above-mentioned binder, light-to-heat converting substance, and solvent, additives such as a dispersant may be added as necessary, and a light-to-heat converting layer coating can be obtained by dissolving or dispersing the mixture in the same manner as in the case of the intermediate layer. The light-to-heat conversion layer can be formed on the intermediate layer by the solvent coating method as in the case of the intermediate layer. The thickness of the photothermal conversion layer is suitably in the range of 0.01 to 10 μm, preferably 0.1 to 5 μm. As described above, a photothermal conversion layer containing a photothermal conversion substance is formed on one surface of the light-transmitting support via an intermediate layer containing a photodegradable compound. Considering the results of the studies conducted by the inventors,
It has been found that the above-mentioned pressing/pressing effect and heat dissipation suppressing effect of the intermediate layer are basically largely dependent on the adhesive force at the interface between the intermediate layer and the light-to-heat conversion layer. That is,
If the adhesive force at the interface is extremely strong, the gas generated as a result of photolysis and the thermal expansion of this gas will prevent the light-to-heat conversion layer from swelling, and the ink layer surface will conform to the roughness of the receiving paper surface. The effect of being pressed and pressed is significantly reduced. Moreover, at the same time, as a result of the thermal expansion of the gas being impeded, the effect of suppressing heat dissipation is also significantly reduced. Based on the above considerations, we have systematically varied the interfacial adhesion force and found that the interfacial adhesion force of the intermediate layer/light-to-heat conversion layer in order to effectively express the effects of the structure of the present invention is determined by the 180° peel test method. It was found that an essential requirement is that the peel strength at 500 g/cm or less is required. Note that various heat-resistant resin films such as polyethylene terephthalate, polyimide, polycarbonate, and cellophane are used as the light-transmitting support used in the present invention. The thickness of the film is 1-
A suitable range is 100 μm, preferably 4 to 30 μm. Further, a vapor-deposited film of a metal such as aluminum, zinc, indium, tin, etc., which is easily destroyed by discharge, is applied to the light-reflecting layer provided on one side of the light-transmitting support. At that time, silica,
It is preferable to provide a highly transparent roughened layer containing fine particles of alumina, tin dioxide, hydrated alumina, etc. between the support and the light-reflecting layer. Next, the thermally transferable solid ink layer provided on the light-to-heat conversion layer will be explained. The heat-transferable solid ink layer may be heat-melting or heat-sublimating, and any of those conventionally used in the field of heat transfer ink sheets can be used. That is, in the case of a heat-melting material, its constituent materials mainly consist of a binder colorant and a softener, which are low melting point substances. A binder made of a low melting point substance is a solid or semisolid substance whose melting point is in the range of 40 to 120°C, and specific examples thereof include carnauba wax, paraffin wax, microcrystalline wax, ester wax, Waxes such as oxidized wax and montan wax, stearic acid,
Higher fatty acids such as behenic acid, higher alcohols such as palmityl alcohol and stearyl alcohol,
Higher fatty acid esters such as cetyl palmitate and cetyl stearate, amides such as acetamide and stearic acid amide, ester gums, rosin derivatives such as rosin phenol resin, polymer compounds such as terpene resins and cyclopentadiene resins, stearylamine, palmitin amine Examples include higher amines such as polyethylene glycol, polyethylene oxide, etc. These low melting point substances can be used alone or in combination of two or more.
Further, the coloring agent can be selected from conventionally known dyes or pigments. Specific examples of cyan pigments include Diaceriton Fast Brilliant Blue-R (manufactured by Mitsubishi Kasei Co., Ltd., trade name), Kayalon Polyester Blue-B-SF Conc (manufactured by Nippon Kayaku Co., Ltd.,
(trade name), magenta pigments include Diaceritone Fastret R (manufactured by Mitsubishi Kasei Co., Ltd., trade name), Kayalon Polyester Pink RCL-E (manufactured by Nippon Kayaku Co., Ltd., trade name), etc., and yellow pigments include: Kayalon Polyester Light Yellow 5G-S (manufactured by Nippon Kayaku Co., Ltd., product name), Eisenspiron Yellow
Examples include GRH (manufactured by Hodogaya Chemical Co., Ltd., trade name). Cyan pigments include cerulean blue phthalocyanine blue, magenta pigments include brilliant carmine and alizarin lake, yellow pigments include Hansa yellow and bisazo yellow, and black pigments include carbon black, graphite, Oil black etc. can be mentioned. Note that thermoplastic resins such as ethylene vinyl acetate copolymer and butyral resin, oil, etc. may be added to the solid ink layer, if necessary. Next, in the case of thermal sublimation, the constituent materials mainly consist of a binder and a coloring agent. The binder preferably has a relatively high melting point or softening point in order to avoid melt transfer during transfer. Specific examples include organic solvent-soluble resins such as polysulfone, polycarbonate, polyester, polyphenylene oxide, cellulose derivatives, polyvinyl alcohol, polyvinyl butyral, hydroxyethyl cellulose, carboxymethyl cellulose, water-soluble or water-dispersible polyesters, and water-soluble Alternatively, examples include water-soluble or water-dispersible resin systems such as water-dispersible acrylic resins, and emulsion systems of the organic solvent-soluble resins described above. The heat sublimable or heat vaporizable dye should be selected from disperse dyes, oil-soluble dyes, acid dyes, mordant dyes, vat dyes, basic dyes, etc., which are generally used in transfer printing of textiles and heat transfer inks. I can do it. Specific examples include azo-based, anthraquinone-based, nitro-based, styryl-based, naphthoquinone-based, quinophthalone-based, azomethine-based, coumarin-based, and fused polycyclic dyes. The sublimation initiation temperature of these dyes is preferably 150°C or lower. In addition, in the solid ink layer, if necessary,
Antiblocking agents, inorganic and organic pigments, antioxidants, ultraviolet absorbers, antistatic agents, crosslinking agents, and the like may also be added. These thermally transferable solid ink layers can be formed by a hot melt coating method or a solvent coating method. The thickness of the ink layer is suitably in the range of 0.1 to 10 μm, preferably 1 to 5 μm. EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but these Examples are not intended to limit the present invention. (Example) Example 1 An average particle size of 5 μm was placed on a transparent support made of polyethylene terephthalate film with a thickness of 12 μm.
By providing a roughened layer with a thickness of 6 μm containing silica (SiO ₂ ), and further providing an Al vapor deposited layer with a thickness of about 500 Å on the roughened layer, a light reflecting layer that can be removed by discharge breakdown recording is created. Obtained. Next, an intermediate layer paint containing a photodegradable compound having the following composition was prepared. Binder: 35% by weight toluene/isopropyl alcohol solution of polyurethane resin (manufactured by Takeda Pharmaceutical Company, trade name: Takerakku E-366)
171 parts by weight Photodegradable compound: 4-diazo-1-diethylamino-2-(4'-chlorophenoxy)-5-chlorobenzene/phosphorus hexafluoride 40 parts by weight Solvent: 456 parts by weight of methyl ethyl ketone Glass beads were added to the above mixed solution, and after dispersion and dissolution treatment for 100 minutes in a paint shaker, an intermediate layer paint was obtained. This paint was coated on the other side of the polyethylene terephthalate film using a wire bar so that the layer thickness after drying at 75° C. for 1 minute was 2 μm to form an intermediate layer. Next, a light-to-heat converting layer coating containing a light-to-heat converting substance having the following composition was prepared. Binder: 30% by weight toluene solution of saturated polyester resin (manufactured by Toyobo Co., Ltd., trade name: Vylon 300) 117 parts by weight
wt% methyl ethyl ketone solution
117 parts by weight Photothermal conversion substance: Carbon dispersion liquid (manufactured by Toyo Ink Co., Ltd., trade name Multilac A-903 Black)
60 parts by weight Solvent: Toluene 106 parts by weight Glass beads were added to the above mixed solution, and after dispersion and solution treatment in a paint shaker for 100 minutes, a light-to-heat conversion layer paint was obtained. Apply the paint onto the intermediate layer using a wire bar to determine the layer thickness after drying at 90℃ for 1 minute.
A photothermal conversion layer was formed by coating to a thickness of 2.5 μm. At this time, the 180° peel strength at the interface between the intermediate layer and the light-to-heat conversion layer was 50 g/cm. Next, three types of hot-melt inks with the following formulations were prepared. Binder: Carnauba wax (mp73℃)
12 parts by weight paraffin wax (mp60℃)
20 parts by weight Additive: 9 parts by weight of oleic acid Pigment: Yellow (Y) Ink: Bisazo Yellow Magenta (M) Ink: Brilliant Carmine Cyan (C) Ink: 9 parts by weight of Phthalocyanine Blue Each of the above mixtures was heated at 95°C. After melt-mixing, the mixture was stirred for 60 minutes using a homomixer to obtain a colored hot-melt ink. The Y, M, and C inks had melting points of 75, 74, and 72°C, and melt viscosities of 126, 34, and 22 cp at 100°C. Each of the inks described above was coated on the photothermal conversion layer by a hot melt coating method so that each layer had a thickness of 3.5 μm to form a thermally transferable solid ink layer, thereby obtaining a discharge transfer recording medium of the present invention. Thereafter, each printing pattern of a character pattern, a solid pattern, and a gradation pattern according to the Daigo method was recorded on the recording medium using a conventional discharge recording device at a voltage applied to the head of 45V. Next, a receiver paper was brought into close contact with the surface of the ink layer, and using a xenon flash device (FX-150 manufactured by Riso Kagaku Co., Ltd.), a flash of light was irradiated over the entire surface of the microphone sheet from the light-reflecting layer side. At this time, the contact pressure between the ink layer surface and the receiving paper surface was adjusted to a constant value of 50 g/cm ² and 100 g/cm ² , and the flash energy was adjusted to a constant value of 13 mJ/mm ² . Furthermore, the receiver paper is
Bond paper with a surface smoothness of 4 to 6 seconds,
Three types of paper were used: 50-60 second copy paper and 300-320 second thermal transfer paper. After irradiation with flash light, the discharge transfer recording medium of the present invention and the image receiving paper were peeled and separated by a 180° peeling method, and the quality of the resulting transfer recording was evaluated according to the following evaluation criteria. That is, by visual inspection and enlarged photographs (25x, 50x), "printing marks", "toggle", "fading",
Observe the degree of ``white spots'' and gradation expression in the solid transfer area. is 1 or more and the gradation expression is also good. ◎ If at least one of "printing scratches", "toggle", "fading", "white spots" and "fogging" occurs, If the degree of the problem is not significant, mark it as ○, "printing scratches", "printing blur", "staining", "white spots"
△ indicates that at least one of the following and "fogging" is relatively noticeable;
A case where the solid transfer portion lacked density was marked as ×. The data are shown in Tables 1 and 2 below. Example 2 Example 1 except that the formulation of the intermediate layer was changed as follows.
A discharge transfer recording medium of the present invention was obtained in the same manner as described above. Binder: Polyester resin (manufactured by Nippon Gosei Kagaku Co., Ltd., product name Nichigo Polyester LP-)
20% by weight methyl ethyl ketone solution of 011)
300 parts by weight Photodegradable compound: 4-diazo-1-diethylamino-2-(4'-chlorophenoxy)-5-chlorobenzene/phosphorus hexafluoride 40 parts by weight Solvent: methyl ethyl ketone 327 parts by weight Example 3 Preparation An intermediate layer was formed in the same manner as in Example 1, except that the following changes were made. Binder: 300 parts by weight of a 20% by weight methyl ethyl ketone solution of vinyl chloride/vinyl acetate copolymer resin (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name Denkavinyl 1000As) Photodegradable compound: 4-diazo-1-morpholino-2,5- Dibutoxybenzene/boron tetrafluoride salt Solvent: 327 parts by weight of methyl ethyl ketone Next, a light-to-heat conversion layer coating containing the following composition of light-to-heat conversion substances was prepared. Binder: 30% by weight petroleum benzine/toluene solution (petroleum benzine/toluene = 50/50) of vinyltoluene/butadiene copolymer resin (manufactured by Guttoyer, trade name Priorite VTL) 233 parts by weight Photothermal conversion substance: Carbon dispersion Liquid (manufactured by Toyo Ink Co., Ltd., product name Multilac A-903 Black)
60 parts by weight Solvent: Toluene 107 parts by weight Glass beads were added to the above mixture, and after dispersion and solution treatment in a paint shaker for 100 minutes, a light-to-heat conversion layer paint was obtained. Apply the paint onto the intermediate layer using a wire bar to determine the layer thickness after drying at 85℃ for 1 minute.
A photothermal conversion layer was formed by coating to a thickness of 3 μm. At this time, the 180° peel strength at the interface between the intermediate layer and the light-to-heat conversion layer was 30 g/cm. Thereafter, in the same manner as in Example 1, a discharge transfer recording medium of the present invention was obtained. Example 4 Example 3 except that the formulation of the intermediate layer was changed as follows.
In the same manner as above, a discharge transfer recording medium of the present invention was obtained. Binder: Ethylene/vinyl acetate copolymer resin (manufactured by Nippon Gosei Kagaku Kogyo Co., Ltd., trade name Soarex R-BH: content of vinyl acetate component 55
300 parts by weight of a 20% toluene solution of 5 Example 3 except that the formulation of the intermediate layer was changed as follows.
In the same manner as above, a discharge transfer recording medium of the present invention was obtained. Binder: 300 parts by weight of a 20% by weight methyl ethyl ketone solution of vinylidene chloride resin (trade name Saran Resin R-202, manufactured by Asahi Kasei Corporation) Photodegradable compound: 4-diazo-1-morpholino-2,5-dibutoxybenzene. Boron tetrafluoride salt 40 parts by weight Solvent: methyl ethyl ketone 327 parts by weight Example 6 A discharge transfer recording medium of the present invention was obtained in the same manner as in Example 3 except that the formulation of the intermediate layer was changed as follows. Binder: 400 parts by weight of a 15% by weight isopropyl alcohol solution of polyamide resin (product name Diaamide Boron fluoride salt 40 parts by weight Solvent: methanol 227 parts by weight Example 7 An intermediate layer was formed in the same manner as in Example 1, except that the formulation was changed as follows. Binder: Microcrystalline wax (manufactured by Nippon Seirosha Co., Ltd., product name Heimitsuku 1070)
20% by weight toluene solution 300 parts by weight Photodegradable compound: 4-diazo-1-morpholino-2,5-dibutoxybenzene/tetrafluoroborate salt 40 parts by weight Solvent: methyl ethyl ketone 327 parts by weight Next, the following A light-to-heat converting layer coating containing a blended light-to-heat converting substance was prepared. Binder: 35% by weight toluene/isopropyl alcohol solution of polyurethane resin (manufactured by Takeda Pharmaceutical Co., Ltd., trade name: Takerakku E-366)
237 parts by weight Photothermal conversion substance: Carbon powder (manufactured by Mitsubishi Chemical Corporation,
Product name MA-100) 12 parts by weight Conductive zinc white (manufactured by Honjo Chemical Co., Ltd.)
5 parts by weight Dissolved: 146 parts by weight Toluene Glass beads were added to the above mixed solution, and after dispersion and dissolution treatment in a paint shaker for 200 minutes, a light-to-heat conversion layer paint was obtained. The paint was applied on the intermediate layer using a wire bar, and the layer thickness after drying at 90℃ for 2 minutes was 2.5 μm.
A photothermal conversion layer was formed by coating the film so as to have the following properties. At this time, the 180° peel strength at the interface between the intermediate layer and the light-to-heat conversion layer was 25 g/cm. Thereafter, in the same manner as in Example 1, a discharge transfer recording medium of the present invention was obtained. Example 8 Example 7 except that the formulation of the intermediate layer was changed as follows.
In the same manner as above, a discharge transfer recording medium of the present invention was obtained. Binder: Carboxy-modified styrene-butadiene rubber (manufactured by Japan Synthetic Rubber Co., Ltd., trade name
JSR0693) 125 parts by weight Photodegradable compound: 4-diazo-1-morpholino-2,5-dibutoxybenzene chloride
zinc chloride salt Solvent: Water 502 parts by weight Example 9 Example 1 except that the formulation of the intermediate layer was changed as follows.
A discharge transfer recording medium of the present invention was obtained in the same manner as described above. Binder: 35% by weight toluene/isopropyl alcohol solution of polyurethane resin (manufactured by Takeda Pharmaceutical Co., Ltd., trade name: Takerakku E-366)
171 parts by weight Photodegradable compound: 1-azido-pyrene Solvent: Methanol 289 parts by weight Example 10 A discharge transfer recording medium of the present invention was obtained in the same manner as in Example 1, except that the color heat-melting ink was changed to the following heat-sublimable ink. Binder: 3 parts by weight of ethyl cellulose Added pigment: 2 parts by weight of white carbon (manufactured by Nippon Silica Co., Ltd., trade name NIPSEAL E-200A) Disperse dye: (manufactured by Nippon Kayaku Co., Ltd.) 10 parts by weight Yellow (Y) ink: Kayaset-IO-
A-G Magenta (M) ink: Kayaset Red B Cyan (C) ink: Kayaset Blue 906 Solvent: Isopropyl alcohol 45 parts by weight Add glass beads to each of the above mixtures, disperse for 120 minutes in a paint shaker, and then This paint was coated onto the photothermal conversion layer using a wire bar so that the layer thickness after drying at 60°C for 2 minutes was 3 μm. Comparative Example 1 A comparative discharge transfer recording medium was obtained in the same manner as in Example 1 except that no intermediate layer was provided. Comparative Example 2 A comparative discharge transfer recording medium was obtained in the same manner as in Example 1 except that the intermediate layer did not contain a photodegradable compound. Comparative Example 3 A comparative discharge transfer recording medium was obtained in the same manner as in Example 1, except that the photothermal conversion layer did not contain a photothermal conversion substance. Comparative Example 4 A comparative discharge transfer recording medium was obtained in the same manner as in Example 1, except that the binder in the intermediate layer was changed to the following thermosetting resin. Binder: Urea/melamine resin (manufactured by Hitachi Chemical Co., Ltd., trade name Melan 445) 109 parts by weight Photodegradable compound: 4-diazo-1-diethylamino-2-(4'-chlorophenoxy)-5-chlorobenzene 6 feet Phosphate salt 40 parts by weight Solvent: xylene 259 parts by weight Butanol 259 parts by weight Comparative Example 5 A comparative discharge transfer recording medium was obtained in the same manner as in Example 1, except that the formulation of the light-to-heat conversion layer was changed as follows. . Binder: 175 parts by weight of 40% by weight methyl ethyl ketone/toluene solution (methyl ethyl ketone/toluene = 50/50) of saturated polyester resin (manufactured by Toyobo Co., Ltd., trade name: Byron 200) Light-heat conversion substance: Carbon dispersion (manufactured by Toyo Ink Co., Ltd., product name) Multi rack A-903 black)
60 parts by weight Solvent: methyl ethyl ketone 165 parts by weight At this time, the 180° peel strength at the interface between the intermediate layer and the light-to-heat conversion layer was 520 g/cm. The results of transfer recording quality obtained from Examples and Comparative Examples are divided into cases where the contact pressure is 50 g/cm ² and 100 g/cm ² and the respective results are shown in Tables 1 and 2. be.

【table】

[Table] (Effects of the invention) According to the present invention, by providing an intermediate layer containing a photodegradable compound, the compound in this layer is photodecomposed by transmitted light and gas is generated. This increases the pressure-contact effect on the image-receiving paper surface, thereby making it possible to transfer a high-level image with high density even on the image-receiving paper with low surface smoothness. As a result, the heat dissipation to the ink layer is significantly suppressed, which further increases the ink layer temperature, amplifying the effect of the ink layer, improving the retention of the molten state in the case of fusible ink, and causes a significant increase in the amount of sublimation, thereby improving transferability.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a sectional view of a conventional example, and FIGS. 3 to 5 are sectional views showing each stage of the discharge transfer method. DESCRIPTION OF SYMBOLS 1... Light-transmitting support, 2... Light-reflecting layer, 3... Light-to-heat conversion layer, 4... Thermal transferable solid ink layer, 5... Receiving paper, 6... Xenon flash lamp, 7... Flash light,
8... Transfer image, 9... Intermediate layer.

Claims (1)

[Scope of Claims] 1. A light-reflecting layer removable by discharge destruction recording is provided on one side of a light-transmitting support, and the other side of the support contains a photodegradable compound consisting of a diazo compound or an azide compound. A light-to-heat conversion layer containing at least one light-to-heat conversion substance selected from inorganic pigments, organic pigments, dyes, ultraviolet absorbers or infrared absorbers, and a thermally transferable solid ink layer are sequentially provided. Discharge transfer recording medium 2: The binder in the intermediate intervening layer containing a photodegradable compound consisting of a diazo compound or an azide compound is at least one type selected from thermoplastic resins, waxes, or rubbers. Discharge transfer recording medium 3 according to claim 1, characterized in that: an intermediate layer containing a photodegradable compound made of a diazo compound or an azide compound; an inorganic pigment;
The 180° peel strength of the interface of the photothermal conversion layer containing at least one photothermal conversion substance selected from organic pigments, dyes, ultraviolet absorbers, or infrared absorbers is
500 g/cm or less, the discharge transfer recording medium 4 according to claim 1, characterized in that the thermally transferable solid ink layer is a thermally meltable solid ink layer or a thermally sublimable ink layer. A discharge transfer recording medium according to claim 1.