JPH082115A - Heat transfer sheet, multicolor heat transfer method and multicolor printed matter - Google Patents

Abstract

(57) [Abstract] [Purpose] A thermal transfer sheet capable of printing on plain paper with conventional thermal energy and capable of clear and diversified multicolor recording even when printed on thermosensitive coloring paper, a multicolor recording method, and Providing those prints. In a thermal transfer sheet having an ink layer formed on one surface of a base film, the ink layer contains a colorant and an erasing agent for hindering or decoloring the thermosensitive color paper. In the thermal transfer sheet, which is characterized in that a first ink layer containing a decoloring agent for preventing or decoloring the color of the thermosensitive coloring paper is formed on one surface of the substrate film, A thermal transfer sheet having at least one second ink layer between a base film, a thermal transfer method using these thermal transfer sheets, and a multicolor printed matter obtained by these methods.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer sheet and a multicolor thermal transfer recording method, and more particularly to a thermal transfer sheet capable of printing on plain paper and multicolor recording when printed on thermosensitive coloring paper, The present invention relates to a multicolor heat transfer method and a multicolor printed matter.

[0002]

2. Description of the Related Art Conventionally, as a system for performing color output, there are a heat-sensitive color developing system, a thermal transfer system, an ink jet system, an electrophotographic system and the like. Among these, the inkjet method has recently become widespread, and the reason for the widespread use is that it is possible to output a color image more easily than other methods. However, with this method, color output is possible in a relatively short time for A4 size paper, but for larger sizes such as A1 size and banners, color output is currently available. It requires a large output time and the device is expensive. Moreover,
The resulting image has a problem in water resistance, and the output color image is unsuitable for outdoor use. Further, the electrophotographic method has a short output time, and the durability of the color image obtained from the principle of fixing the toner is excellent,
The high price of the device and the need for maintenance hinder its widespread use.

In contrast to these methods, the thermosensitive color recording method using a thermosensitive color paper and a thermal head has a short output time, and the cost of the apparatus for outputting a large size is not as high as that of other methods. It's also free of maintenance. Further, in the melt heat transfer method using a heat transfer sheet, since a pigment-based coloring material is used, the obtained color image has very excellent durability such as light resistance and has the advantage that it can be used in outdoor applications. It is generally possible to output a color image at a relatively low cost.

When printing by the thermal transfer method, a thermal transfer sheet having a thermal transferable ink layer (hereinafter simply referred to as an ink layer) provided on one surface of a base film is used. This conventional thermal transfer sheet uses a base material film such as condenser paper or paraffin paper having a thickness of 10 to 25 μm or a plastic film such as polyester or cellophane having a thickness of 2 to 25 μm, and wax or pigment or dye. It is manufactured by coating an ink layer mixed with a colorant such as.

On the other hand, the thermosensitive coloring system can output a document or a figure at a lower cost than the thermal transfer system. When the output product becomes large, the unit price per output product is smaller than that of the thermal transfer system. It is widely used because it is advantageous. Further, some methods have been proposed for performing multicolor printing by using these thermosensitive coloring methods. As one of means for carrying out multicolor recording using the thermosensitive coloring paper, there is a thermosensitive coloring paper having a two-layer or three-layer structure. For example, in JP-A-57-178791, two coloring layers having different coloring temperatures and colors are provided, and a decoloring agent for decoloring the coloring of one layer is contained between the two coloring layers. An intermediate layer is provided. This makes it possible to print in two different colors by changing the printing temperature.

On the other hand, a so-called thermosensitive coloring paper is used as the transfer material,
An ink layer is transferred from the thermal transfer sheet to the color-developing surface, and at this time, two or more color images are easily formed by combining the hue of the ink layer of the thermal transfer sheet and the hue of the thermosensitive coloring paper in different combinations. The method is 3-25
It is proposed in Japanese Patent No. 355 and Japanese Patent No. 3-32476. Furthermore, although it is not a multicolor recording system, it is not disclosed in JP-A-63-3.
Japanese Patent No. 15292 discloses that a thermosensitive coloring paper is colored in advance and only a necessary portion is decolorized by using a decoloring agent present in a thermal transfer sheet, so-called blank printing is performed, and it is used as a presentation tool such as OHP. The method used is described.

[0007]

[Problems to be solved by the invention] However,
With the two-color thermosensitive color paper described in JP-A-57-178791, once the color paper to be printed is determined, the combination of print colors is limited. In addition, although there is no problem in the two-color recording, the realization becomes difficult as the number of colors increases, for example, four colors and five colors. Further, in the method described in Japanese Patent Publication No. 3-32476, two-color recording is achieved by a combination of low-temperature transfer and high-temperature color development. However, when the temperature is high, the recorded image always shows the color of the ink layer and the color of the color-developing paper. As it is a mixed color with, it is not possible to achieve multicolor recording of bright colors such as blue and red. On the contrary, according to the method described in Japanese Patent Publication No. 3-25355, although two-color recording is performed by low-temperature color development and high-temperature transfer, color mixing at the time of high-temperature transfer is inevitable as described above. Furthermore, in the method described in JP-A-63-315292,
This is a so-called blank character manufacturing method and is useful for forming an OHP image, but it cannot form a multicolor image.

As a method of solving such a problem, there is a method of incorporating a white pigment having a high hiding power in the ink layer or an outer layer thereof (JP-A-2-214694). However, there is a problem in that clear chromatic color printing cannot be performed because the color tone becomes lighter and pastel. Further, heat from the thermal head is taken by the concealing layer, which requires a considerable amount of printing energy. Therefore, an object of the present invention is to print on plain paper with conventional heat energy, and also to print on a heat-sensitive color-developing paper, a thermal transfer sheet capable of clear and colorful multicolor recording, a multicolor recording method, and those It is to provide printed matter.

[0009]

The above object can be achieved by the present invention described below. That is, the present invention is a thermal transfer sheet formed by forming an ink layer on one surface of a base film, wherein the ink layer contains a colorant and a decolorizing agent that prevents or decolors the color of the thermosensitive color paper. A thermal transfer sheet characterized by being formed on one surface of the substrate film, a thermal transfer sheet comprising a first ink layer containing a decoloring agent for preventing or decoloring the color of the thermosensitive coloring paper, A thermal transfer sheet having at least one second ink layer between an ink layer and a base film, a thermal transfer method using these thermal transfer sheets, and a multicolor printed matter obtained by these methods. is there.

[0010]

When the ink layer is printed on the thermosensitive coloring paper, the decoloring agent present in the ink layer or in the transfer layer suppresses or decolors the thermosensitive coloring paper due to heat during printing. Further, even if thermal transfer printing is performed on a portion on which color development printing has been performed in advance, the color development portion is erased by the action of the decolorizing agent. Therefore, the hue of the transferred ink layer does not change, and clear and diversified multicolor recording is possible.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in more detail with reference to the preferred embodiments. A cross-sectional view of a preferred example of the thermal transfer sheet of the present invention is shown in FIG. The thermal transfer sheet shown in FIG. 1a is an example in which an ink layer 2 containing a colorant and a decolorant is formed on a base film 1. The example shown in FIG. 1b is an example in which a slip layer 3 for heat resistance and running property with respect to a thermal head is formed on the substrate film surface opposite to the ink layer in the example of FIG. 1a, and shown in FIG. 1c. An example is the substrate film 1 and the ink layer 2 in the example of FIG. 1b.
And a mat layer 4 for suppressing the glossiness of the printed matter and providing an antistatic effect to the thermal transfer sheet, if necessary. The example shown in FIG. An example in which one ink layer 5 and a second ink layer 6 are provided, and the example shown in FIG. 1e is an example in which the slip layer 3 and the mat layer 4 are provided in the example of FIG. 1d, and is shown in FIG. 1f. An example is shown in Figure 1.
1a is an example in which a protective layer 7 for preventing settling of the ink layer 2 is provided, and the example shown in FIG. 1g is an example in which the protective layer 7 is provided in the example in FIG. 1c, and FIG. The example shown is an example in which the protective layer 7 is provided in the example of FIG. 1e.
These examples show preferred examples of the present invention,
The invention is not limited to these illustrated examples.

As the base film used in the thermal transfer sheet of the present invention, the same base film as that used in the conventional thermal transfer sheet can be used as it is, and other materials can also be used, in particular Not limited. Specific examples of the preferred substrate film include, for example, polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride, polystyrene, nylon, polyimide, polyvinylidene chloride, polyvinyl alcohol, fluororesin, chlorinated rubber, ionomer and the like. Plastics, condenser paper, paraffin paper, and other non-woven fabrics, woven fabrics, etc.
Further, it may be a base film which is a composite of these. The thickness of the base film can be appropriately changed according to the material so that its strength and thermal conductivity are appropriate.
The thickness is preferably, for example, 2 to 25 μm.

The ink layer provided on the substrate film is
It may be composed of a colorant and a vehicle, and may further contain various additives if necessary. The colorant is preferably an organic or inorganic pigment or dye having good characteristics as a recording material, for example, a pigment having a sufficient coloring density and not discolored by light, heat, temperature or the like. Of course, carbon black is preferable for black monochromatic printing, and chromatic colorants such as cyan, magenta, and yellow are used for other hues. The amount of these colorants used is generally preferably about 3 to 70% by weight in the ink layer. As the vehicle, waxes, drying oils, resins, mineral oils, cellulose and rubber derivatives and the like and mixtures thereof are used.

Typical waxes include microcrystalline wax, carnauba wax and paraffin wax. Furthermore, various types of Fischer-Tropsch wax, various low molecular weight polyethylene, wood wax, beeswax, spermaceti wax, ivowa wax, wool wax, shellac wax, candelilla wax, petrolactam, polyester wax, partially modified wax, fatty acid ester, fatty acid amide, etc. Wax is used. Further, various thermoplastic resins known as resins, for example, ethylene resin, acrylic resin, polyester resin, styrene-
A butadiene copolymer, an acrylonitrile-butadiene copolymer, or the like is used, and by using these alone or in combination, the adhesion of the ink layer to various recording papers such as thermosensitive coloring paper, plain paper, and synthetic paper is improved. You can As a method of forming an ink layer on a base film, in addition to hot melt coating, hot lacquer coating,
Examples include gravure coat, gravure reverse coat, roll coat, knife coat, and many other means.
The thickness of these ink layers is 0.5 to 10 μm as in the conventional case.
The thickness may be m, preferably 1 to 5 μm.

In one embodiment of the present invention, a decoloring agent is contained in the ink layer when forming the above ink layer. The decoloring agent is an agent having a function of preventing the leuco dye or the like contained in the thermosensitive coloring paper from being colored by the addition of protons or the like due to heat, or having a function of decoloring the leuco dye or the like that has been colored. , Which vary depending on the type of the heat-sensitive color former, but generally preferred examples include, for example, thermoplastic polyethers,
Polyethylene glycol, polypropylene glycol and their derivatives, alcohols such as stearyl alcohol, dicyclohexyl phthalate, plasticizers such as diethylhexyl phthalate and di2-ethylhexyl adipate, supercooling materials such as polycaprolactone, polyester,
Acetamide, stearamide, organic ammonium salt,
Organic amine, urea, thiourea and their derivatives, thiazoles, pyrroles, pyrimidines, piperazines,
Known decoloring agents such as guanidines, indoles, imidazoles, imidazolines, triazoles, morpholines, piperidines, amidines, formazines, pyridines and olefin waxes are used.

The above-mentioned decoloring agent preferably has a melting point of 40 to 100 ° C. when heated by the DSC method (temperature rising rate of 7.5 ° C./min.), And thermal transfer using a decoloring agent which is liquid at room temperature. The sheet is inferior in storage stability. On the other hand, a thermal transfer sheet using a decoloring agent having a melting point of more than 100 ° C. cannot obtain sufficient printing property and decoloring property with ordinary printing energy. However, even a decoloring agent that is liquid at room temperature can be used as a decoloring agent in the present invention by forming a microcapsule covering the decoloring agent with a polymer material having an appropriate melting point. Further, in order to use these decoloring agents for the material of the ink layer, the melt viscosity at 100 ° C. is preferably 1,500 cps or less, and the melt viscosity at 100 ° C. is 1,500 cps.
If the material exceeds the range, the permeation of the decoloring agent to the thermosensitive color developing paper is deteriorated when thermal transfer printing is performed, and a sufficient decoloring effect cannot be obtained.

These decolorizers can be used alone as a vehicle for the ink layer as long as they have appropriate melting points and melt viscosities. However, when various fastnesses such as film strength are low, other decoloring agents can be used. It is preferable to use the above binder, for example, the above waxes or resins in combination. Further, as described in claims 5 and 6, by providing the second ink layer on the thermal transfer sheet of the present invention, it is possible to improve the robustness of the printed portion after printing. . The second ink layer can also be used for purposes other than the above.
For example, as described in claim 6, by forming the second ink layer with a wax as a main component, in addition to the improvement of the fastness, a peeling property for improving the peeling property at the time of printing. It can also have a function as a layer.

Further, other binders, for example, the above waxes, ethylene resins, styrene-butadiene copolymers, acrylonitrile-butadiene copolymers, thermoplastic resins such as acrylic resins are used together or aggregated in the ink layer. It is preferable to provide a second ink layer as described above between the ink layer and the base film for the purpose of imparting force. As the second ink layer, the waxes, ethylene resin,
It is preferable to use a thermoplastic resin such as an acrylic resin or a polyester resin.

Further, by adding a colorant to the second ink layer as described in claim 4, it is possible to have a function as a colored layer, and further, in claim 3 above.
By including a decolorizing agent as described in
It is possible to improve the decoloring performance as compared with the case where the decoloring agent is added only to the first ink layer. As described above, the second ink layer can have not only a single function according to the purpose as described above but also a plurality of functions by appropriately combining materials satisfying each requirement. Is. Further, when the desired performance is not sufficiently achieved with only the second ink layer, the third, fourth, ..., And second ink layers may have a multi-layered structure, if necessary.

Among the decoloring agents used in these ink layers, compounds having an ether bond in the molecule are effective in preventing or decoloring the color of the thermosensitive color developing paper. For example, polyethylene glycol and its derivatives,
Examples thereof include polypropylene glycol and its derivatives, polyglycerin and its derivatives, aliphatic ethers, aromatic ethers and cyclic ethers.

Of the above, polyethylene glycol and its derivatives, polypropylene glycol and its derivatives are particularly preferable. Considering the melting point, melt viscosity and coagulation characteristics required as a decoloring agent, the weight average molecular weight is 7,
000 or less, more preferably 1,000 to 5,0
00 is the above compound. Weight average molecular weight is 1,000
When the weight average molecular weight exceeds 7,000, the above-mentioned microencapsulation is necessary because the liquid becomes liquid when the amount is less than 7,000, and when the weight average molecular weight exceeds 7,000, the heat sensitivity of the decoloring agent is increased when the thermal transfer printing is performed as in the case of the melt viscosity. Permeability to color paper is reduced, and sufficient decoloring effect cannot be obtained.

Further, since polyethylene glycol generally has a high affinity with water, it may cause a problem in the storability of the heat transfer sheet obtained under high humidity conditions. In such a case, the terminal hydroxyl group of polyethylene glycol may be changed. At least one of them is preferably etherified or esterified with an alcohol, an organic acid, or a monomer, oligomer or polymer having a carboxyl group, and the storage stability of the resulting thermal transfer sheet is improved.

Not only when polyethylene glycols are used, but also when a decoloring agent having low storage suitability is used, another method for improving environmental preservation characteristics is to mix a filler in the ink layer or to form a protective layer. A method of providing it on the outside of the ink layer may be used. When mixing a filler in the ink layer, the filler is not limited to both organic filler and inorganic filler as the type, but as the organic filler, for example, ethylene-vinyl acetate copolymer, polyethylene, ionomer, a filler made of polystyrene or the like. The inorganic filler is preferably calcium carbonate, silica, kaolin, titanium oxide or the like. The particle size of these fillers is preferably larger than the thickness of the ink layer. When the particle size is larger than the thickness of the ink layer, the filler can absorb the pressure applied to the ink layer, and the blocking resistance of the thermal transfer sheet is improved. On the other hand, when the particle size of the filler is smaller than the thickness of the ink layer, the filler is buried in the ink layer, and the blocking resistance effect as described above cannot be obtained.

The amount of the filler added is 1 m when the number of the fillers present in the layer containing the filler or the number of the filler protruding on the surface of the layer containing the filler is 1 m.
A range of 500-100,000 per m ² is desirable. If it is less than 500, sufficient environmental preservation suitability cannot be obtained, while if it exceeds 100,000, transferability and decoloring performance of the ink layer are significantly impaired. On the other hand, when the protective layer is provided on the outside of the ink layer, the above-mentioned waxes as the protective layer, for example, carnauba, paraffin, microcrystalline, polyethylene, etc., or resins, for example, silicon-modified acrylic, styrene-butadiene rubber, Polyesters, acrylics, olefins, etc. can be used alone or by mixing them in an appropriate ratio, but when the above fillers are mixed with these, the same principle as when mixed in the ink layer is obtained. Thus, the environmental preservation characteristics can be further improved.

When these decoloring agents are not used alone during the preparation of the ink but used by mixing with other vehicles, they are in the range of about 10 to 500 parts by weight per 100 parts by weight of the binder such as wax or resin. Or it may be used in an amount of 0.5 g or more / m ^{2 in} the ink layer or on the surface of the ink layer. Further, the thermal transfer sheet of the present invention having the constitution as shown in FIG. 1d may be used alone or when the above-mentioned decoloring agent is solid on the surface of the second ink layer 6 of the thermal transfer sheet produced by the usual method. The first ink layer 5 may be formed by coating with a different binder such as the above wax. In this case, the thickness of each ink layer is not particularly limited, but for example, the thickness of the first ink layer is about 0.1.
About 10 to 10 μm, preferably 0.5 to 3 μm,
The thickness of the second ink layer is about 0.01 to 5 μm, preferably 0.1 to 1 μm.

In forming the ink layer as described above, the thickness between the base film side and the ink layer is 0.1 to 10 μm.
A matte layer can be formed to some extent to give the printed matter a matte feeling. The mat layer is formed by hot melt coating,
It may be a hot lacquer coat, emulsion coat, gravure coat, gravure reverse coat or roll coat. The release layer generally has a thickness of about 0.1 to 5 μm.

In the thermal transfer method of the present invention, as shown in FIG. 2, the thermal transfer sheet 8 of the present invention and the thermosensitive coloring paper 9 are used, the thermal transfer sheet is overlaid on the thermosensitive coloring paper, and the thermal head 10 is placed from the back of the thermal transfer sheet. The feature is that heat is applied at. In the thermal transfer method of the present invention, for example, as shown in FIG. 2A, the thermal transfer sheet 8 (ink hue: red) of the present invention is overlaid on a part of the surface of the thermal transfer paper 9 that develops black, and the thermal head 10 is used. When the heat transfer sheet is peeled off after applying the heat with, the red printing 11 is performed on the portion where the heat transfer sheet exists, as shown in FIG.
Since the portion to which the heat is applied does not develop a black color, the transferred ink layer 11 shows a clear red color. Here, 12 indicates a coloring portion of the thermosensitive coloring paper.

Further, even if a thermal transfer sheet is overlaid on a part of the surface of a thermosensitive coloring paper which has been colored black in advance and thermal transfer is carried out, due to the effect of the decoloring agent in the ink layer of the thermal transfer sheet,
Black coloring is erased and clear red printing is performed. In such printing, the thermal energy and printing pressure applied to the thermal head are set to 0.2 mJ / dot, 2 kg / line, as is often set when printing with a conventional line type head having a resolution of about 200 dpi. (However, 1
Even if the line is about A4 width), a sufficient decoloring effect can be obtained for thermosensitive coloring paper. Therefore, considering the complexity of control of the printing device, these are basically thermal transfer under the same conditions. Coloring is also preferably performed, but the printing pressure and the amount of applied energy can be changed in some cases.
0.4mJ / dot, 4k to enhance the erasing effect
About g / line is desirable.

The thermosensitive color-developing paper used in the present invention, and the thermosensitive color-developing paper known per se, can be used as the material to be transferred in the present invention. These heat-sensitive color-developing papers are those in which a color-developing layer containing a colorless dye that is colored by an acid and a solid acid that is a color-developing agent is provided on the surface of a paper that is a base material. The coloring agent may be divided into separate layers, or may be mixed in one layer, and a dye and / or a developer may be developed by a shell material that is destroyed by heat to improve stability. The agents may each be microencapsulated. Phenols are generally frequently used as the color developer used in the thermosensitive coloring paper, and bisphenol or a derivative thereof, particularly bisphenol A is preferable in the present invention. Such a thermosensitive coloring paper is used as the thermal transfer sheet of the present invention. When used in combination, excellent decoloring property can be obtained.

The above-mentioned thermal transfer sheet of the present invention and the conventionally known thermosensitive coloring paper may be prepared separately, or the ink layer surface and the coloring surface of both of them may be temporarily adhered to each other to form an integrated type. May be. These have a form corresponding to the mechanism of the printing apparatus, and if necessary, a ribbon-shaped thermal transfer sheet may be provided with a lead tape, end marks, or the like.

[0031]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. In the text, parts and% are based on weight unless otherwise specified. Example 1 A 6.0 μm-thick polyethylene terephthalate film having a slip layer on the back surface and a mat layer having the following composition on the surface was used as a base film, and the following ink composition was formed on the mat layer. Was applied at a rate of 3 g / m ² to form an ink layer to obtain a thermal transfer sheet of the present invention. Matte layer composition Carbon black 24 parts Polyester resin 16 parts Dispersant 1.5 parts Curing agent 3 parts Ink composition Red pigment (lake red C) 10 parts Carnauba wax 40 parts Aliphatic amine 50 parts

Example 2 In the same manner as in Example 1, 3 g / m ² of the following ink composition was added.
To form an ink layer, and the following decoloring agent ink layer is further applied to the surface at a rate of 1 g / m ² to form a decoloring agent layer. Got the sheet. Ink composition Blue pigment (phthalocyanine blue) 10 parts Paraffin wax 40 parts Carnauba wax 30 parts Ethylene / vinyl acetate copolymer 20 parts Decolorant ink composition Dicyclohexyl phthalate 50 parts Carnauba wax 50 parts

Example 3 In the same manner as in Example 1, 3 g / m ² of the following ink composition was used.
Is applied to form an ink layer, and the following decoloring agent ink layer is further applied to the surface at a rate of 1 g / m ² to form a decoloring agent layer. Got the sheet. Ink composition Black pigment (carbon black) 17 parts Ethylene / vinyl acetate copolymer 10 parts Paraffin wax 50 parts Carnauba wax 24 parts Decolorant ink composition Polyethylene glycol (molecular weight 4,000) 100 parts

Example 4 A thermal transfer sheet of the present invention was obtained in the same manner as in Example 1 except that the aliphatic amine in Example 1 was replaced with polypropylene glycol (molecular weight 6,000). Comparative Example 1 The following ink composition was used in the same manner as in Example 1 to obtain 3 g / m ²
A thermal transfer sheet of a comparative example was obtained by applying an ink layer at the following ratio to form an ink layer. Ink composition Green pigment (phthalocyanine green) 10 parts Carnauba wax 30 parts Paraffin wax 40 parts Ethylene / vinyl acetate copolymer 20 parts

Use Example 1 The thermal transfer sheets of Examples 1 to 4 and Comparative Example 1 were superposed on the left half of the following thermosensitive coloring paper, and the printing speed was 9 msec / l.
Fixed at ine, applied energy of 200 dpi thermal head is 0.4 mJ / dot, printing pressure 4 kg / lin
print as e, peel off the thermal transfer sheet after printing,
The printed image was observed and the results shown in Table 1 below were obtained. Thermosensitive coloring paper (1) Black purple thermosensitive coloring paper (dye: crystal violet lactone, developer: bisphenol A (2) Red thermosensitive coloring paper (dye: 3-diethylamino-5
-Methyl-7-chlorofluorane, developer: 4,4 'isopropylidenediphenol)

[0036]

[Table 1]

Example 5 The following ink composition was applied onto the matte layer of a polyethylene terephthalate film having a thickness of 4.5 μm, the slip layer being provided on the back side and the matte layer described in Example 1 being provided on the surface. An ink layer was formed by coating at a rate of 3 g / m ² to obtain a thermal transfer sheet of the present invention. Using this thermal transfer sheet, printing was performed on the thermal recording paper (1) in Use Example 1 under the printing conditions: applied energy 0.4 mJ / dot and printing pressure 4 kg / line, and the results shown in Table 2 below were obtained. Ink composition Red pigment (lake red C) 20 parts Polyethylene glycol (molecular weight 4,000) 80 parts

Example 6 A thermal transfer sheet of the present invention was obtained using the following ink composition in the same manner as in Example 5, and a printing test was conducted in the same manner as in Example 5. Ink composition Red pigment (lake red C) 20 parts Polyethylene glycol (molecular weight 4,000) 50 parts Ethylene / acrylic acid copolymer 30 parts Example 7 A slip layer is provided on the back surface and a release layer is provided on the surface. 3 g / cm of an ink layer having the following composition on a release layer of a polyethylene terephthalate film having a thickness of 4.5 μm
The heat transfer sheet of the present invention was obtained by forming the sheet to a thickness of ² , and a printing test was conducted in the same manner as in Example 5. Ink composition Red pigment (lake red C) 20 parts Polyethylene glycol-polypropylene glycol copolymer (molecular weight 10,000) 80 parts

Example 8 2 g of a second ink layer having the following composition was placed on a release layer of a polyethylene terephthalate film having a thickness of 4.5 μm, which has a slip layer on the back surface and a release layer on the front surface.
cm ² and then an ink composition having the following composition at a rate of 3 g / m ² to form a first ink layer on the surface to obtain a thermal transfer sheet of the present invention. A printing test was conducted in the same manner as in No. 5. Second ink layer composition Ethylene / vinyl acetate copolymer 100 parts First ink layer composition Red pigment (lake red C) 20 parts Polyethylene glycol (molecular weight 4,000) 80 parts

Example 9 2 g of a second ink layer having the following composition was placed on a release layer of a polyethylene terephthalate film having a thickness of 6.0 μm, which has a slip layer on the back surface and a release layer on the front surface.
It was formed to have a thickness of cm ^{2, and} a first ink layer having the following composition was formed to have a thickness of 3 g / m ² on the surface, a thermal transfer sheet of the present invention was obtained, and a printing test was conducted in the same manner as in Example 5. Second ink composition Red pigment (lake red C) 20 parts Ethylene / vinyl acetate copolymer 80 parts First ink layer composition Polyethylene glycol (molecular weight 6,000) 100 parts

Example 10 In the same manner as in Example 5, the following ink composition was applied to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Blue pigment (phthalocyanine blue) 20 parts Heat-fusible microencapsulated product of polyethylene glycol having a molecular weight of 600 50 parts Styrene butadiene rubber 30 parts Example 11 The decolorizer of Example 10 is heat-melting property of polypropylene glycol having a molecular weight of 400. An ink layer was formed in the same manner as in Example 10 except that the microencapsulated product was used to obtain a thermal transfer sheet of the present invention, and a printing test was performed in the same manner as in Example 5. Example 12 Using the thermal transfer sheet of Example 5, printing was performed under printing conditions: applied energy of 0.2 mJ / dot and printing pressure of 2 kg / line, and the results shown in Table 2 below were obtained.

Example 13 Using the thermal transfer sheet of Example 6, printing was performed under printing conditions: applied energy of 0.2 mJ / dot and printing pressure of 2 kg / line, and the results shown in Table 2 below were obtained. Example 14 In the same manner as in Example 5, the following ink composition was applied to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Red pigment (lake red C) 20 parts Polyethylene glycol distearate (molecular weight 6,000) 50 parts Ethylene / acrylic acid copolymer 30 parts

Example 15 In the same manner as in Example 5, the following ink composition was applied to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Red pigment (lake red C) 20 parts Polyethylene glycol (molecular weight 11,000) 80 parts Example 16 The following ink composition was applied in the same manner as in Example 5 to form an ink layer to form an ink layer of the present invention. A thermal transfer sheet was obtained and a printing test was conducted in the same manner as in Example 5. Ink composition Red pigment (lake red C) 20 parts Polyethylene glycol (molecular weight 4,000) 70 parts Ethylene / acrylic acid copolymer 10 parts

Example 17 The following ink composition was applied in the same manner as in Example 5 to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Red pigment (lake red C) 20 parts Polyglycerin stearic acid ester 50 parts Ethylene-acrylic copolymer 30 parts Example 18 The following ink composition was applied in the same manner as in Example 5 to form an ink layer. A thermal transfer sheet of the present invention was formed and a printing test was conducted in the same manner as in Example 5. Ink composition Polyethylene glycol 4000 (reagent) 30 parts Ethylene-acrylic acid copolymer 25 parts Filler (ethylene-vinyl acetate copolymer particles, particle size 6 μm) 30 parts (30000 / mm ² ) Red pigment (lake red C ) 15 copies

Example 19 In the same manner as in Example 5, the following ink composition was applied to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Polyethylene glycol 4000 (reagent) 50 parts Ethylene-acrylic acid copolymer 33 parts Filler (silica particles, particle size 5.5 μm) 2 parts (1500 pieces / mm ² ) Red pigment (lake red C) 15 parts Implementation Example 20 In the same manner as in Example 5, the following ink composition was applied to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was performed in the same manner as in Example 5. Ink composition Polyethylene glycol 4000 (reagent) 30 parts Ethylene-acrylic acid copolymer 5 parts Filler (ethylene-vinyl acetate copolymer particles, particle size 4 μm) 50 parts (150,000 / mm ² ) Red pigment (lake red C ) 15 copies

Example 21 In the same manner as in Example 5, the following ink composition was applied to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Polyethylene glycol 4000 (reagent) 50 parts Ethylene-acrylic acid copolymer 34.5 parts Filler (silica particles, particle size 5.5 μm) 0.5 part (300 / mm ² ) Red pigment (lake red C 15 parts Example 22 The following ink composition was applied in the same manner as in Example 5 to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Polyethylene glycol 4000 (reagent) 30 parts Ethylene-acrylic acid copolymer 35 parts Filler (ethylene-vinyl acetate copolymer particles, particle size 1 μm) 10 parts (25,000 / mm ² ) Red pigment (lake red C ) 15 copies

Example 23 The following ink composition was applied in the same manner as in Example 5 to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Polyethylene glycol 4000 (reagent) 50 parts Ethylene-acrylic acid copolymer 25 parts Filler (ethylene-vinyl acetate copolymer particles, particle size 6 μm) 10 parts (20000 / mm ² ) Red pigment (lake red C 15 parts Example 24 A thermal transfer sheet of the present invention was obtained in the same manner as in Example 8 except that the composition for the first ink layer of Example 8 was changed to the following composition for the first ink layer. A printing test was conducted in the same manner as in. Composition for the first ink layer Ethylene-vinyl acetate copolymer 80 parts Polyethylene glycol (molecular weight 4000) 20 parts

Example 25 In the same manner as in Example 5, the following ink composition was applied to form an ink layer to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Ink composition Red pigment (Lake Red C) 20 parts Polyoxyethylene / bisphenol A ether 50 parts Ethylene-acrylic acid copolymer 30 parts Example 26 Ethylene as a protective layer on the outside of the ink layer of the thermal transfer sheet of Example 6 A vinyl acetate copolymer was applied at a ratio of 0.5 / m ² to obtain a thermal transfer sheet of the present invention, and a printing test was conducted in the same manner as in Example 5. Example 27 A thermal transfer sheet of the present invention was obtained in the same manner as in Example 26 except that the composition for protective layer in Example 26 was changed to the following composition, and a printing test was performed in the same manner as in Example 5. Composition for protective layer Ethylene-acrylic acid copolymer 40 parts Filler (ethylene-vinyl acetate copolymer particles, particle size 6 μm) 60 parts

Comparative Example 2 In the same manner as in Example 5, the following ink composition was applied to form an ink layer, and a thermal transfer sheet of Comparative Example was obtained.
A printing test was conducted in the same manner as in 2. Ink composition Red pigment (lake red C) 20 parts Carnauba wax 80 parts

[0050]

[Table 2]

* 1: When the background color is not erased and mixed, the color is X. When the color is erased but not perfect, the color mixture is recognized is Δ. When the color is not completely erased, almost no color mixture is observed. The case where no color mixture was observed was marked with ◯, and the case where no color mixture was recognized was marked with ⊚. * 2: ∘ when no print blur was observed, and ∘ when the blur was not a problem. * 3: ⊚ when there was no disturbance at the boundary between the printed part and the non-printed part, and ◯ when there was no problem. * 4: Viscosity at 100 ° C * 5: Evaluation after storage for 3 days in a temperature of 40 ° C and a humidity of 80% ⊚ ... No migration of ink layer components to the back surface is observed. ○: ・ Transfer of ink layer components to the back is slightly observed.

Use Example 2 The thermal transfer sheet prepared in Example 18 was slit, a lead tape and an end mark were attached, and the sheet was mounted on an ink ribbon cassette for a word processor. Attach the cassette containing the created ink ribbon to the word processor,
Printing was performed on the colored portion and the uncolored portion of the thermosensitive coloring paper used in Use Example 1. As a result, clear two-color printed matter was obtained. Use Example 3 The thermal transfer sheet prepared in Example 18 was cut into A1 size sheets, and then overlaid on A1 size thermosensitive coloring paper and printed with a large printer. As a result, clear two-color printed matter can be obtained, and printing can be performed at a lower cost than two-color printing only by thermal transfer printing.

[0053]

As described above, according to the present invention, when the ink layer is printed on the thermosensitive coloring paper, the decoloring agent contained in the ink layer suppresses or decolors the coloring of the thermosensitive coloring paper due to heat during printing. Therefore, the hue of the ink layer does not change. Further, by adopting such a mechanism, it is not necessary to change the printing conditions of the thermal head at the time of transferring the ink layer and at the time of developing the color of the thermosensitive coloring paper alone, so that the smooth printing can be performed.
Further, the thermal transfer sheet and method of the present invention is particularly useful for sending an image signal to a large-sized printer and producing a printed matter enlarged by a large-sized printer, and, for example, a large-sized poster,
It is particularly useful for producing large-sized color images for banners, hop applications (for example, advertisements, leaflets, etc.).

[0054]

[Brief description of drawings]

FIG. 1 is a diagram schematically illustrating a cross section of a thermal transfer sheet of the present invention.

FIG. 2 is a diagram schematically illustrating a thermal transfer method of the present invention.

[Explanation of symbols]

 1: Substrate film 2: Ink layer 3: Slip layer 4: Matt layer 5: First ink layer 6: Second ink layer 7: Protective layer 8: Thermal transfer sheet 9: Thermosensitive coloring paper 10: Thermal head 11: Ink image 12: Color image

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location 7267-2H B41M 5/26 C 7267-2H A

Claims (17)

[Claims] 1. A thermal transfer sheet comprising a base film and a thermal transfer ink layer formed on one surface of the substrate film, wherein the ink layer comprises a colorant and a decolorizing agent for preventing or decoloring the thermosensitive color paper. A thermal transfer sheet characterized by containing. 2. A thermal transfer sheet comprising a substrate film and a first thermal transferable ink layer containing a decolorizing agent for preventing or decoloring the thermosensitive color paper on one surface of the substrate film. At least 1 between the base film and the base film
A thermal transfer sheet having a second thermal transferable ink layer. 3. The heat transfer sheet according to claim 2, wherein the second heat transferable ink layer contains a decoloring agent which prevents or decolors the color of the thermosensitive color developing paper. 4. The thermal transfer sheet according to claim 2, wherein the second thermal transfer ink layer contains a pigment as a colorant. 5. The thermal transfer sheet according to claim 2, wherein the second thermally transferable ink layer contains a thermoplastic resin as a main component as a vehicle. 6. The heat transfer sheet according to claim 2, wherein the second heat transferable ink layer contains waxes as a main component as a vehicle. 7. The thermal transfer sheet according to claim 1, wherein the decolorizer has a melt viscosity at 100 ° C. of 1,500 cps or less. 8. The thermal transfer sheet according to claim 1, wherein the decoloring agent is liquid at room temperature and is contained in the microcapsules. 9. The thermal transfer sheet according to claim 1, wherein the decoloring agent is a compound having an ether bond. 10. The thermal transfer sheet according to claim 1, wherein the decoloring agent is polyethylene glycol, polypropylene glycol, or a derivative thereof. 11. A protective layer for preventing set-off of heat transferable ink is provided outside a layer containing a decoloring agent.
The thermal transfer sheet of item 0. 12. The thermal transfer sheet according to claim 1, wherein the thermal transfer ink layer or the protective layer contains an organic and / or inorganic filler. 13. The thermal transfer sheet according to claim 12, wherein the average particle size of the filler is larger than the thickness of the layer containing the filler. 14. The number of the fillers present in the layer containing the filler or the number of the fillers protruding on the surface of the layer containing the filler is 500 to 1 per 1 mm ² .
The thermal transfer sheet according to any one of claims 12 to 13, wherein the number is in the range of 0,000. 15. The thermal transfer sheet according to claim 1 is overlaid on a thermosensitive coloring paper that develops a hue different from that of the colorant of the thermal transfer ink layer of the thermal transfer sheet, and the thermal head is placed from the back side of the thermal transfer sheet. A multicolor thermal transfer method characterized in that heat is applied to transfer the thermal transferable ink layer, and at the same time as the transfer of the thermal transferable ink layer or before and after the transfer, the thermosensitive color developing paper is heated to develop color. 16. The multicolor thermal transfer method according to claim 15, wherein both the transfer of the thermal transferable ink layer and the color development of the thermosensitive color developing paper are performed by a thermal head without positively changing the applied energy. 17. A multicolor printed matter obtained by the method according to claim 15.