JPS6219488A - Heat-sensitive transfer recording media and heat-sensitive transfer recording method - Google Patents

Abstract

PURPOSE:To form a distinct multi-colored heat-sensitive transfer recording picture, by using the heat-sensitive transfer recording media prepared by successively arranging the sublimating dye containing layer and the dye acceptable layer on the base material. CONSTITUTION:The layer containing sublimating dye 4 is laminated on the heat-resisting base material 3 and further, the dye acceptable layer 5 easy to collect the sublimated sublimating dye is laminated thereon. The dye contained in the layer containing sublimating dye 4 sublimates according to the applied temperature. That is, when the lowest temperature among the sublimation starting temperature of those dyes is applied, only the sublimating dye having the lowest sublimation starting temperature sublimates to transfer to the acceptable layer. As the applied temperature is raised, the sublimating dye corresponding to that temperature is further added to the sublimating dye having a low sublimating starting temperature to transfer to the acceptable layer. Thereby, because the acceptable layer attached to the material to be recorded contains much dye of the same color series or otherwise, is mixed with the dye of different color series according to the applied temperature, the color to be colored varies. Because the content of dye in the dye acceptable layer can be regulated by the regulation of applied temperature utilizing the sublimating dye as a colorant, the multi-colored picture having good coloration and excellent gradation, can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a thermal transfer recording medium used for thermal transfer recording, more specifically, a thermal transfer recording medium containing a sublimable dye and capable of producing a clear image by selecting the recording surface condition and material. The present invention relates to a thermal transfer recording medium that can be formed by first forming a thermal transfer recording medium, and a thermal transfer recording method using the thermal transfer recording medium.

[Background Art] In recent years, with the rapid development of the information industry, various information processing systems have been developed, and recording methods and devices suitable for each information processing system have been developed. One such recording method is the thermal recording method, which has been widely used recently because the equipment used is lightweight, compact, noiseless, and has excellent light operability and maintainability. .

Among these thermal recording methods, a thermal transfer recording method has recently attracted particular attention. This recording method is generally
A thermal transfer material is used, in which a thermal transfer layer consisting of a colorant dispersed in a heat-melting binder or a dye layer containing a sublimable dye is provided on a sheet-like support. Alternatively, the dye layer is superimposed on the recording material so as to be in contact with the recording material, and heat is supplied from the support side of the thermal transfer material using a thermal head or the like to transfer the melted thermal transfer layer or sublimated dye to the recording material. By doing so, a transferred recorded image corresponding to the heat supply pattern is formed on the recording material.

The above thermal transfer recording method using a sublimable dye is
The colors of the resulting image are beautiful. It has advantages such as being able to easily produce neutral colors, but in particular, the dye layer contains sublimable dyes of different colors with different sublimation temperatures, and by selectively applying heat according to the image, it is possible to easily produce intermediate colors. An efficient method for obtaining multicolor images has been proposed.

[Problems to be solved by the invention] However, sublimable dyes are difficult to adhere to ordinary recording paper;
Furthermore, since the grains of the recording paper are rough and the sublimated dye gets into the grains, it is necessary to use a special recording paper that has a layer on one surface that easily captures the sublimable dye. Furthermore, it was not possible to prevent the sublimated dye from scattering to areas other than the desired areas of the recording paper, making it impossible to obtain images with excellent clarity.

The present invention was made in view of the above problems, and its purpose is to make use of the advantages of sublimable dyes, such as clear colors in the images obtained and the ability to easily produce intermediate colors, while also producing vivid multicolor images. To provide a method for forming a thermal transfer recorded image without selecting recording paper.

[Means for Solving the Problems] The above object of the present invention is to provide a thermal transfer recording medium in which a sublimable dye-containing layer and a dye-receiving layer are sequentially disposed on a support, and also to provide a thermal transfer recording medium in which a sublimable dye-containing layer and a dye-receiving layer are sequentially disposed on a support. This is achieved by the thermal transfer recording method used.

[Effect] The mechanism of thermal transfer according to the present invention is as follows.

That is, the thermal transfer recording medium is superimposed on the recording material so that its dye-receiving layer is in contact with the recording material, and a desired portion of the sublimable dye-containing layer is heated to a temperature at which the dye to be sublimated is sufficiently sublimated. do. The dye sublimated by heating is immediately captured by the adjacent dye-receiving layer. Immediately after this heating, when the thermal transfer recording medium is separated from the recording material, the entire receptor layer, or only the portion of the dye receptor layer that has captured the sublimable dye, is separated from the other dye receptor layers and is deposited onto the recording surface. Glue. The sublimable dye captured in the dye-receiving layer is sufficiently diffused in the dye-receiving layer, and the dye-receiving layer adheres to the recording surface, resulting in a desired recording on the recording material. .

In the transfer recording method of the present invention, since the dye-receiving layer serves to adhere the dye to the recording surface, recording can be performed on any material to which the molten dye-receiving layer adheres.

[Embodiments of the present invention] Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of one embodiment of the thermal transfer recording medium of the present invention, in which a sublimable dye-containing layer 4 is laminated on a heat-resistant support 3 and further captures the sublimated dye. A dye-receiving layer 5 is laminated thereon.

As the support 3, conventionally known films and papers can be used as they are, but for example, films of relatively heat-resistant plastics such as polyester, polycarbonate, triacetyl cellulose, polyamide, polyimide, cellophane, sulfur paper, etc. can be suitably used. The thickness of the support is preferably about 2 to 15 microns when using a thermal head as a heat source during thermal transfer. The heat resistance of the support can be improved by providing a heat-resistant protective layer made of silicone resin, fluororesin, polyimide resin, epoxy resin, phenol resin, melamine resin, nitrocellulose, etc. It is also possible to use support materials with low heat resistance. Further, for reinforcement, the support body 3 can be multi-layered if necessary.

For example, as disclosed in Japanese Unexamined Patent Publication No. 58-12790, conductive fine particles such as carbon black or metal are dispersed in the support 3 to increase its specific resistance to 102 to 103.
It may have a conductivity of about Ω·01, or as disclosed in Japanese Unexamined Patent Publication No. 58-220795, etc.
A highly conductive layer made of a vapor-deposited metal film or the like may be provided between the conductive heat-generating support 3 and the dye-containing layer 4.

Examples of sublimable dyes constituting the sublimable dye-containing layer 4 include disperse dyes represented by anthraquinone compounds and azo compounds, and basic dyes represented by indolenine compounds and leucophenoxazine compounds. Sublimation dyes of choice include. However, from a practical point of view, those having a sublimation start temperature of 200°C or less are preferable, and specifically, for example, Kayaset Yellow AC, Kayaset Red B, Kayaset Blue 908 (IJ
Top, manufactured by Nippon Gunpowder, product name), Resilien Yellow TGL
, Ceresplu-GN, Resolin Red B, Resolin Yellow GRN (manufactured by Bayer, product names), Dianex Yellow 6O-5E, Dianex Brilliant Ye O-50-E, Dianex Scarlet 3R-FE, , Dyanix Scarlet PT
B-137 (manufactured by Mitsubishi Kasei, product name), Miketon Yellow 5G, Miketon Red BSF, Miketon Blue FTK (product name, manufactured by Mitsui Toatsu), Sumikalon Yellow E-4GL, Sumikalon Red F- BGL
, Sumirikironbrute GRL, etc.

The sublimable dye-containing layer 4 usually contains a plurality of sublimable dyes of different colors or similar colors, which are the above substances and have different sublimation start temperatures.

In the present invention, 1 degree of sublimation initiation of a sublimable dye refers to a temperature defined as follows. That is, a certain amount (for example, 10
100 liters of sublimable dye was placed uniformly on an area of 5 x 5 cm, and a hot plate at a predetermined temperature was placed on the dye for 1 second to inject 20 g.
/ cm2 pressure. The temperature of the hot plate at which the optical density of the film at the maximum absorption wavelength of the sublimable dye captured (transferred) onto the film (recording material) shows 0.10 is defined as the sublimation start temperature. Further, the sublimation end temperature refers to the temperature of the hot plate at which the optical density shows 0.90 when the change in the amount of transmitted light of the film is determined by the same method as the sublimation start temperature.

In addition, the sublimable dyes of different colors as used in the present invention refer to dyes whose hues are clearly different from each other. For example, when using two-color dyes, dyes of different colors are selected from different groups of the three primary colors of cyan, magenta, and yellow. Two colors are suitable.

When the sublimable dye-containing layer contains two sublimable dyes of different colors, it is desirable that the sublimation end temperature of the first sublimable dye and the sublimation start temperature of the second sublimable dye are equal. , it is appropriate that the difference is at least 5°C or less. If the temperature difference between these temperatures exceeds 5°C, the temperature range for producing a change in the color density of the first sublimable dye may become too narrow, or the change in the color density of the first sublimable dye may become too narrow. This is not preferable because the total temperature range of the temperature range for developing the color and the temperature range for developing the hue change of the mixed color of the first sublimable dye and the second sublimable dye becomes too wide.

Further, the thermal transfer recording medium of the present invention may contain a third sublimable dye in addition to the first and second sublimable dyes. In this case, the third sublimable dye is the first sublimable dye. It is preferable that the sublimable dye has a different color to each of the sublimable dye and the second sublimable dye, and the third sublimable dye has a sublimation start temperature that is lower than that of the second sublimable dye. It is preferable that the temperature is approximately equal to the sublimation end temperature.

Furthermore, in the present invention, similar coloring agents refer to those whose hues are very similar to each other; for example, all of these coloring agents belong to the same group of the three primary colors of cyan, magenta, and yellow. It is necessary. On the other hand, "another different color" for specifying the second colorant refers to a color whose hue is clearly different from the hue of the first colorant group. For example, the first colorant group is cyan. If it belongs to one of the three primary colors of , magenta, and yellow,
It is necessary that it belongs to a different group.

When the sublimable dye-containing layer contains a plurality of sublimable dyes of the same color, it is preferable that the transfer start temperature of the lowest one and the highest one among them differ by at least 5°C, It is more preferable that there is a difference of 10°C or more, but it is not appropriate that there is a difference of 50°C or more, and the transfer start temperature of these colorants is approximately equal in number. It is preferable that

The dye contained in the sublimable dye-containing layer 4 as described above is sublimed depending on the applied temperature.

That is, when the lowest temperature among the sublimation start temperatures of these dyes is applied, only the sublimable dye having the lowest sublimation start temperature sublimes and transfers to the receiving layer. As the applied temperature is increased, sublimable dyes corresponding to the temperature are further added to sublimable dyes having a low sublimation start temperature and transferred to the receiving layer.

Therefore, the color of the receptor layer attached to the recording material changes depending on the applied temperature, as more dyes of the same color or dyes of different colors are mixed together.

The A sublimable dye-containing layer 4 is usually constructed by dispersing the above-mentioned plurality of sublimable dyes in a binder resin. The binder resin is suitably one having a melting point or softening point higher than the temperature at which the sublimable dye dispersed therein almost completely sublimates. Examples of such binder resin include phenol resin, melamine resin,
Epoxy resin, silicone resin, urea resin, diallyl phthalate resin, alkyd resin, acetal resin, acrylic resin, methacrylic resin, polyester resin, starch and its derivatives, cellulose resin, vinyl halide resin, polyolefin, polystyrene, polyvinyl acetal , polyamide, polyvinyl alcohol, polycarbonate, polysulfone, polyether sulfone, polyester, polyether, polyacrylonitrile, polyimide, polyamideimide, and polymer blends such as As resin and ABS resin.

Specifically, the method of providing the sublimable dye-containing layer 4 on the support 3 is, for example, by kneading a sublimable dye and a binder resin with a suitable solvent to form a dispersion liquid, and applying the dispersion liquid using a roll coater or a blade coater. For example, the coating material may be coated on the support 3 using any coating means such as a bar coater, and dried if necessary. The thickness of the sublimable dye-containing layer 4 is usually 0.1 to 10 μs, preferably 0.5 μs.
~5 tiles.

Dye-receiving R5 does not have adhesive properties at normal temperatures but becomes adhesive when heated. During transfer recording, the entire receiving layer may be transferred to the recording material, or only the portion where the sublimable dye has been captured may be transferred to the recording material. In the former case, during recording, a temperature at which the dye-receiving layer 5 exhibits adhesive properties is constantly applied to the transfer recording medium.

In other words, instead of sublimating the sublimable dye and transferring only the dye-receiving layer that captures it onto the recording material, the non-image forming area is also heated within a temperature range in which the sublimable dye does not sublimate. Adhere the dye-receiving layer to the entire surface of the material.

On the other hand, in the latter case, during the heating process to sublimate the sublimable dye, the heat-applied portion of the dye-receiving layer melts and adheres to the recording surface, and the thermal transfer recording medium is immediately separated from the recording material. Only the fused portion remains adhered to the recording surface.

For this reason, the lowest temperature at which the dye-receiving layer exhibits adhesion is preferably at least 5°C lower than the lowest sublimation start temperature of the sublimable dye contained in the dye layer. Considering stability, it is preferable that the temperature is 55°C or higher, and the dye-receiving layer should be one that maintains a certain level of viscosity and does not flow even when sublimating a sublimable dye with the highest sublimation initiation temperature. . The thickness of this dye-receiving layer is at least 2 times the thickness of the sublimable dye-containing layer, although it depends on the type of sublimable dye, since it is necessary to capture most of the amount of sublimation when the sublimable dye sublimes. It is desirable that the thickness be at least 30% thick.

The constituent materials of this dye-receiving layer include polyester resin,
Polyamide resin, polystyrene resin, agril resin, polycarbonate resin, epoxy resin, polyvinylpyridine resin, polyolefin resin, etc. can be used.

The dye-receiving layer can also be obtained by coating the above-mentioned material on the sublimable dye-containing layer by a conventional coating method.

In this case, in order to coat without damaging the sublimable dye-containing layer, it is preferable to select a solvent or to modify it into a hydrogen emulsion.

When recording is performed using the thermal transfer recording medium of the present invention as described above, a desired portion of the sublimable dye-containing layer is heated. When a thermal head is used as the heating means, heating is performed as follows. Namely, the thermal transfer recording medium is superimposed on the recording material so that its dye-receiving layer is in contact with the recording material as shown in FIG. Then, heat is supplied to a desired portion of the heat-sensitive transfer recording medium from the support side. The heat supplied from the thermal head is transmitted through the support 3 to sublimate the sublimable dye contained in the sublimable dye-containing layer at a rate corresponding to the applied temperature.At the same time, the sublimated dye is transferred to the sublimable dye-containing layer. The dye is captured in the upper dye-receiving layer, and when the thermal transfer recording medium is immediately separated from the recording material, the sublimable dye is captured and only the dye-receiving layer in the uniformly colored portion is covered, as shown in Figure 2. It remains attached to the surface of the recording material.

In the thermal transfer recording medium of the present invention, an adhesive layer may be further provided on the dye-receiving layer as shown in FIG. Suitable materials for forming the layer include ethylene vinyl acetate copolymer and ethylene acrylic copolymer. This adhesive layer can be formed using the same means as the dye-receiving layer. By selecting the constituent material of this adhesive layer, it is possible to record on recording paper that would not have good adhesion with the dye-receiving layer alone, as well as on the surface of all materials such as metal, cloth, plastic, glass, and ceramics. .

Note that in the case of the current heating method, the heat-sensitive transfer medium itself generates heat by applying current from a needle-like or multi-stylus-like recording electrode instead of a thermal head, but of course heat is applied by such a method. You may.

[Effects of the Invention] When transfer recording is performed using the thermal transfer recording medium of the present invention and the thermal transfer recording method of the present invention, dye content in the dye-receiving layer can be reduced by using a sublimable dye as a coloring material and adjusting the application temperature. Since the amount can be adjusted, a multicolor image with good color development and excellent gradation can be obtained.

Further, since the dye-receiving layer is provided in contact with the dye-containing layer, diffusion of the sublimated dye is suppressed, and a clear image can be obtained.

Furthermore, the sublimable dye in the dye-containing layer migrates to the dye-receiving layer at a rate depending on the applied temperature, and the dye-receiving layer that captures this dye is adhered to the recording surface, so it can be used regardless of the recording material. It can also record on metal, cloth, wood, plastic, ceramics, glass, etc.

Furthermore, when the entire receiving layer is transferred to a recording material, characteristics such as glossiness of the recording surface can be adjusted by adjusting the components of the receiving layer.

There are other effects.

〔Example〕

Hereinafter, the present invention will be explained in more detail based on Examples.

Example 1 Polyester resin Atrac (trade name, manufactured by Kao Corporation) 100 parts by weight Dye Miketone Polyester Yellow YL (trade name, manufactured by Mitsui Toatsu Co., Ltd.) 15 parts by weight Methyl ethyl ketone
1000 parts by weight of the above composition was thoroughly and uniformly stirred in a 7 triter, and the resulting mixture was coated on a 3.5-thick polyethylene terephthalate film so that the coating thickness after drying would be approximately tog. After coating with a wire bar and drying, a polyamide resin solution, which is a component of the receiving layer, is further coated on top of the above composition with a wire bar to a thickness of 1.
A recording material for thermal transfer was prepared by applying the coating to give a temperature of 3-. Note that the sublimation start temperature of dye A was 65°C.

This thermal transfer recording medium was mounted on a thermal transfer recording device (Canoward CM-45S, trade name, manufactured by Canon ■), and the thermal energy supplied to the heat was applied to 0.3 to 0.7 layers.
/ dot in 5 steps, and the temperature applied to the thermal transfer recording medium was changed in 5 steps in the range of 65 to 200°C, and a color photographic image was reproduced on high-quality paper.
It had clear color gradation ranging from pale yellow to deep yellow, and a clear recorded image was obtained despite the pale color.

Example 2 Polyester resin Atrac (trade name, manufactured by Kao ■) 100 parts by weight Dye Miketone Polyester Yellow 115G (trade name, Mitsui Toatsu Co., Ltd.) 15 parts by weight Dye Kayaset Red 12B (trade name 1) (manufactured by Nippon Kayaku Co., Ltd.) 15 parts by weight Methyl ethyl ketone 1000 parts by weight The above composition was sufficiently uniformly stirred in a 7 triter, and the resulting mixture was dried on a polyethylene terephthalate film with a thickness of 3.5 μs. After coating using a wire bar and drying so that the subsequent coating thickness is about 10 μs, a polyolefin resin solution, which is a component of the receptor layer, is further applied on the layer of the above composition using a wire bar to a thickness of 10 μs. A thermal transfer recording material was prepared. The sublimation start temperature of dye B was 72°C, and the sublimation start temperature of dye C was 110°C.

This thermal transfer recording medium is attached to a thermal transfer recording device (Canoward CW-45S, trade name, manufactured by Canon ■), and the thermal energy supplied to the thermal head is 0.3 to 0.7 + sJ.
/ dot, and the temperature applied to the thermal transfer recording medium was changed in 8 steps in the range of 65 to 200,000. A clear recorded image with clear color gradation ranging from orange to red was obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a thermal transfer recording medium of the present invention, and FIG. 2 is a cross-sectional view of a thermal transfer recording medium of the present invention having an adhesive layer. Fig. 3 is a cross-sectional view showing the process in which the receiving layer of the thermal transfer recording medium shown in Fig. 1 is brought into contact with the recording material and heated with a thermal head, and Fig. 4 is a cross-sectional view showing the process in which the receiving layer of the thermal transfer recording medium of Fig. 1 is brought into contact with the recording material and heated with a thermal head. FIG. 3 is a cross-sectional view showing how the receptor layer is adhered to the support. l, recording medium 2, recording medium 3 having an adhesive layer, support 4, sublimable dye-containing layer 5, dye-receiving layer 6, contact M layer 7, recording medium 8, thermal head

Claims (4)

[Claims] (1) A thermal transfer recording medium characterized in that a sublimable dye-containing layer and a dye-receiving layer are sequentially disposed on a support. (2) The thermal transfer recording medium according to claim 1, wherein the sublimable dye-containing layer contains a plurality of sublimable dyes. (3) The thermal transfer recording medium according to claim 1, further comprising an adhesive layer laminated on the dye-receiving layer. (4) A thermal transfer recording medium comprising a sublimable dye-containing layer and a dye-receiving layer disposed in sequence on a support is superimposed on a recording material such that the receptor layer is in contact with the recording material, and the thermal transfer recording After applying different temperatures to different desired regions of the medium depending on the color and density of the desired image to cause the receiving layer to receive the sublimable dye, at least the portions of the receiving layer that have received the sublimable dye are coated. A thermal transfer recording method characterized by transferring onto a recording material.