JPS5964391A - Heat sensitive transfer recording medium - Google Patents

Abstract

PURPOSE:To obtain a recording medium capable of forming an indelible image rich in gradation reprotucibility, generating no unnecessary transfer image due to pressure prior to thermal recording and having good preservability, by providing an image receiving layer by coating in close vicinity to an image forming substance-containing layer. CONSTITUTION:An image receiving layer 3 receiving image forming substance and capable of being transferred to a medium 5 to be transferred by heating is provided on a support (e.g., paper or a plastic sheet) 1 by coating in close vicinity to an image forming substance-containing layer 2 containing the image forming substance (e.g., azo-toluene, P-nitroanisole or m-amino-benzophenone) capable of imparting an image by heating to form a recording medium 4. As the substance for forming the image receiving layer 3, paraffins, carnaba wax and beeswax are pref. and the above-mentioned layer 3 is pref. provided to the surface of the image forming substance-containing layer 2 directly or indirectly by coating.

Description

[Detailed description of the invention] The present invention relates to thermal transfer recording media.

Conventionally, thermal transfer recording media, which are formed by transferring an image onto plain paper using a thermal printer or thermal facsimile, have been made using heat-melting substances such as pigments or sublimable dyes, which are transferred by heating. Melting, sublimation, on the medium
Alternatively, a method of forming an image by volatilization is known6. In addition, a transfer T6 material has been reported in which a color forming agent and a color developer are added to a heat-melting material and the color develops when heated. However, when using sublimable dyes, the dye density of the transferred image may change from time to time not only before recording but also after recording due to the sublimation property of the dye, which has the disadvantage of poor storage stability. Ta. However, although the method of transferring by heating a heat-melting substance containing pigments, etc. has excellent storage stability, the optical reflection density of the transferred image changes based on the change in the amount of image-forming substance per unit area of transfer. The essential drawback is that gradation cannot be expressed by changing the gradation.

The coloring agent described in JP-A-56-120393,
Thermal transfer recording media containing a color developer are easily colored by light, acid, alkali, pressure, etc., which pass before and after recording because the color former and developer are contained in the same layer. Is it a disadvantage of poor storage? have.

Therefore, the first object of the present invention (function of heating temperature and thermal transition')
lJ'-The recording medium is provided. .

The second object of the invention is to provide a layer containing an image-forming substance (hereinafter referred to as an image-forming substance-containing layer) that can provide good storage stability without producing unnecessary transferred images due to pressure, etc., before heating and recording. ), and an H image-receiving layer (hereinafter referred to as an image-receiving layer) capable of receiving the image-forming substance and transferring it to a transfer medium by heating. We have found that VC can achieve this.

- Any support that can be used in the present invention may be paper, plastic, metal, etc. as long as it does not soften when heated for a short time at about 200°C or less, and condenser paper, polyethylene terephthalate film, and aluminum foil are particularly preferably used. . The thickness of each layer can be determined depending on the material of the support, etc., but in general, if it is 3 μm or less, it is difficult to coat a layer containing the image-forming substance Z.
3 to 4.0 l as it is disadvantageous in terms of thermal efficiency at m or more.
1m is desirable.

In the thermal transfer recording medium of the present invention, it is preferable that the image-forming substance-containing layer itself is thermally stable so as not to cause any damage to the transfer medium when heated.

Is there a binder in this layer for this? Preferably, the binder contains mT, and as the binder advantageously used, various thermally stable materials known in the art can be used. For example, gelatin, volivyl alcohol, polyvinyl butyral, methyl cellulose, volley x-nal, polyvinyl butyral, etc. can be mentioned.

The image-forming substance contained in the image-forming substance-containing layer according to the present invention is preferably a substance that itself transfers to the image-receiving layer by melting or the like when heated to about 45°C or higher. It can also be used for For example, azobenzene derivatives, nido. The melting point of benzene derivatives, thiophyl J-nols derivatives, aniline derivatives, etc. is 45°C ~
One having a temperature of 120°C is preferably used. Particularly preferred are azotoluene, azobenzene, azo7enethole, N,N-dimethyl-rll-nido-r1aniline, P-
2) lJ7=sol, m-aminobenzophenone, P-
Aminobenzophenone, P-nitrone-N, N-dimethylanilide, 4-nitro-2-aminoanisole, nitrophenylhydrazine, P-nitrobenzyl The heating temperature during transcription is related to the heating time and the image-receiving layer. The temperature can be determined by taking into account the melting point of the substance used in the process, but it is preferably room temperature or higher, more preferably about 45°C or higher.

The composition of the image-forming substance-containing layer in the present invention is as follows: binder 5
-70% (weight ratio), the image forming substance is preferably in the range of 30-90% (weight ratio), particularly preferably the binder is 10-3%
0% (weight ratio), image forming substance 70-90% (weight ratio)
The proportion of is advantageous.

The material forming the image-receiving layer in the thermal transfer recording medium of the present invention is preferably a material that is solid at room temperature and has a melting point when heated, and materials that can be used are known in the art. There are thermo-flexible substances such as waxes, higher alcohols, and higher fatty acids.

Specifically, paraffins, carnauba wax, beeswax, ceresin wax, polyethylene wax, etc. are used singly or in combination, taking their melting temperatures into consideration.

In the thermal transfer recording medium of the present invention, an intermediate layer Y can be provided between the image-forming substance-containing layer and the image-receiving layer. The intermediate layer may melt when heated or may be free of solvent. In the former case, the image may be transferred to the transfer medium together with the image-receiving layer. In the latter case, the condition is that the image-receiving layer must not be prevented from receiving the image-forming substance.

One method of using the thermal transfer recording medium of the present invention is to heat the support from the side on which the image-forming substance-containing layer is not coated using a thermal head, thermal pen, iron, or other device capable of emitting heat. It is desirable to do so.

Using the thermal transfer recording medium of the present invention, images can be recorded on transfer media such as various types of paper such as coated paper and drawing paper, and resin films such as polyethylene terephthalate film.

In the thermal transfer recording medium according to the present invention, an image-forming substance-containing layer and an image receptor layer are formed on a support by VC as follows.
Can be coated with C. First, the image forming substance occupied layer '7
a' For coating, for example, a layer containing an image-forming substance or a liquid dispersed in a solution containing the above-mentioned binder is used, or the binder is heated and melted without using a solvent to form an image on the object. Dissolve or disperse the substance and pour this liquid into a wire bar,
Coating can be carried out on the support using a commonly known coating device such as a brush or a coater. At this time, in order to improve the adhesion between the support and the image-forming substance-containing layer, there is a gap between the support and the image-forming substance-containing layer.
C: It is also possible to apply a so-called undercoat layer.

A preferred example of the heat-sensitive transfer recording medium of the present invention is as follows. That is, the image is thermally transferred from the image-forming substance-containing layer to the image-receiving layer.

The image-forming substance-containing layer is not transferred onto the transfer medium, but only the image-receiving layer is transferred. Therefore, the YC density of the transferred recorded image according to the present invention is determined by the amount of the image forming substance that has migrated to the image-receiving layer. That is, when recording images and sounds using the thermal transfer recording medium of the present invention, not only can intermediate IMY be expressed by the area ratio of halftone dots, etc., but also five intermediate tones can be expressed by so-called density modulation. There are advantages.

Further, in the thermal transfer recording medium of the present invention, since the 'WJ image-forming material-containing layer and the image-receiving layer are coated separately, the storage stability is excellent.

The present invention has the advantage that uniform density can be obtained not only on the recording side but also on solid images over a wide area, and fine gradation can be obtained even on photographic images.

Preferred embodiments of the present invention will be shown below, but the present invention is not limited to these embodiments.

Example 1 Gelatin 19”r: Solution 'aj dissolved in 2JJml of water
While stirring at 80°C, azobenzene 411Y [
[After cooling, cool this liquid to 50℃. This solution was dispersed in a sand mill for 2 hours while being maintained at 50° C. to obtain coating solution 1.

According to the dispersion method described in Japanese Patent Application Laid-Open No. 56-120393, the mixture was dispersed in 20 Tnl of water to obtain a coating solution 2.

Coating liquid 1 was applied onto polyethylene terephthalate with a thickness of 6 μm using a wire bar Z, and after drying, the thickness was 3.2 μm.
Forming a layer containing an image-forming substance (1) Spreading a coating liquid (2) on the dried layer containing the image-forming substance using a wire bar and drying it to obtain an image-receiving layer having a thickness of 2.4 μm. The heat-sensitive transfer recording medium of the present invention is obtained by bringing the coated side of the heat-sensitive transfer recording medium into close contact with a plain paper surface and changing the temperature with an iron from the support side.
After heating for a few seconds, an orange transfer image can be obtained on plain paper. The optical reflection density of this image was measured using a Z reflection densitometer (manufactured by Roku Konishi).

At temperatures of 1oo'C and 120°C+150°C, the reflection densities are 0.20, 0.57, and 1.17, respectively.
And one. In this way, in the present invention, KN,N-dimethyl-
Except for using 2 g of m-nitroaniline, the results were as expected.

This sample was subjected to the same transfer method as in Example 1, and the heating temperature of the iron and the optical reflection density of the red transferred image were determined in Example 1.
It was measured in the same way. Iron heating temperature 100℃, 120℃
℃ and 150℃, the optical reflection density of the transferred image is 0.35, 0.82, and 1.41, respectively, and as in Example 1, the thermal transfer recording medium according to the present invention has Comparative Example of Optical Reflection of Transferred Image A mixture of 20 ml of Coating Solution 1 and 20 ml of Coating Solution 2 obtained in Example 1 was applied onto a polyethylene terephthalate film with a thickness of 6 μm using a wire knife, dried, and thickened. A thermal transfer recording medium having a layer thickness of 3.5 μm was obtained.

The same transfer method as in Example 1 was carried out on this heat-sensitive transfer recording medium. Iron heating temperature lOO℃, 120℃, 15
The yC reflection density of the 0'C transfer image is 0.
51, 0.44, and 0.63, and it was not possible to change the optical reflection density of the transferred image in response to the heating temperature.

[Brief explanation of drawings]

FIG. 1 shows a thermal transfer recording medium 4 and a transfer medium 5 of the present invention.
and display the heating device 6. Furthermore, 1 and 2.3 represent a support, an image forming substance-containing layer, and an image receiving layer, respectively. Agent Yoshi Kuwahara Beautiful procedural amendment special π short J Nagatome Kazuo Wakasugi 1 Naka I'1 Personal indication 111' Iwa 5 F 1 Special y1 (No. 175138'
fj2 Name of the invention Thermal transfer recording medium: 3 Relationship with the name to be supplemented Patent applicant address Tokyo [1-26-21.4 Nishi-Shinjuku, Shuku-ku
Name (+27) Konishiroku? -3' Shin Kogyo Co., Ltd. representative director Nobuhiko Kawamoto 4 agent Jl': 111 Higashi 5; (To 1me 1ff11) Sakuri-cho H 6, full text of specification subject to amendment 7, contents of amendment (1 ) Amend the description as shown in the attached sheet 0 Correction Description 1, Title of the invention Thermal transfer recording medium 2, Claims (1) Heating the image-forming substance-containing layer containing the image-forming substance A heat-sensitive recording medium comprising an image-receiving layer that transfers an image-forming substance to a transfer recording medium by coating the image-forming substance-containing layer on a thermally stable support. , an image-receiving layer is coated directly or indirectly on the surface of the image-receiving layer. 3. Detailed Description of the Invention The present invention provides a transferred image on a transfer medium that has rich gradation expression and cannot be tampered with. Related to a new thermal transfer recording medium for forming. Conventionally, thermal transfer recording media, such as thermal printers and thermal printers, which transfer and form images onto plain paper using a V-type, use hot bath meltable substances containing pigments, etc. Alternatively, the sublimable dye is melted in a bath, sublimated, or
Alternatively, a method of forming images by interpolating them is known. In addition, color forming agent and color developer 1! It has also been reported that FIJ is added and color is developed and transferred when heated. However, when using sublimable dyes, the dye density of the transferred image may change from time to time not only before recording but also after recording due to the sublimation property of the dye, resulting in poor storage stability. It was. In addition, the method of transferring by heating a hot melt substance containing pigment@ has excellent storage stability, but on the other hand, the optical reflection density of the transferred image changes based on the change in the amount of image forming substance per unit area of transfer. The essential drawback is that it is not possible to perform gradation expression. 4) Thermal transfer recording medium containing the color forming agent and color developer described in JP-A-56-120393 is
]" and a color developer are contained in the same layer, so it has the disadvantage of being easily colored by sources, acids, alkalis, pressure, etc., and having poor storage stability. Therefore, the first object of the present invention is to provide a thermal transfer recording medium that can control the optical reflection density of a transferred recorded image as a function of heating temperature to obtain an image with rich gradation reproduction that cannot be tampered with. It is a mouth to do. The second object of the present invention is to create a thermal transfer recording medium that has good storage stability and does not generate unnecessary transferred images due to pressure or the like before heating recording. It is to provide. This purpose is to sequentially form a layer containing an image-forming substance on a support that can form an image by heating (hereinafter referred to as an image-forming substance-containing layer), and a layer that receives the image-forming substance and forms a transfer medium by heating. It has been found that this can be achieved by a heat-sensitive transfer recording medium characterized in that it is coated with an image-receiving layer C (hereinafter referred to as image-receiving layer) that can be transferred to The support may be paper, plastic, metal, etc. as long as it does not soften when heated for a short time at the heating temperature at which the image-forming material transfers to the image-receiving layer and is transferred to the transfer recording medium. Especially for a short time at about 200°C or less. Any material that does not soften when heated may be used, and in particular, condenser paper, polyethylene terephthalate film, and alumino paper are preferably used. Their thickness can be determined depending on the material of the support, etc., but generally 3.
If it is less than 40 μm, it is difficult to coat a layer containing an image forming substance, and if it is more than 40 μm, it is disadvantageous in terms of thermal efficiency.
~40 μm is desirable. In the thermal transfer recording medium of the present invention, the layer that holds the image forming substance is one that can hold the image forming substance in a particulate or molecular state, and is formed by a binder that allows the image forming substance to undergo V-transfer when heated. And this addition. Q] is not transferred onto the surface of the transfer recording medium when heated. ii! exists in this layer! ii Imaging material kerf 110
It may also contain substances that assist in migration during heat. Examples of the binder for forming this layer include commonly known thermally stable binders such as casein, gelatin, polyvinyl alcohol, polyvinyl butyral, methyl cellulose, gum arabic, polyester, and polyvinyl butyral. is preferred. Polypylene, 4 (Restyrene, Polyvinylchloride)
Do. Non-inventively, the image-forming substance contained in the image-forming substance-containing layer is such that when DO is heated to 15°C or higher, it melts, evaporates or sublimates itself, and is captured by the migration auxiliary substance present in the image-forming substance-containing layer. Any substance may be used as long as it can be transferred to the image-receiving layer by stimulation or the like. For example, the melting point of azobenzene derivatives, nitrobenzene derivatives, thiophenol derivatives, anionic conductors, etc. is 45℃~
120'C is preferably used. Particularly preferred are azotoluene, azobenzene, azophenethole, N,N-dimethyl-m-nitroaniline, P-nitroanisole, m-aminobenzophenone, P-aminobenzophenone, P-nitrone-N,N-dimethylanilide 4-nitro -2-aminoanisole, nitrophenylhydrazine, and P-nitrobenzyl acetate. Therefore, the heating temperature when heating the thermal transfer recording medium according to the present invention for transfer recording can be determined by considering the relationship with the heating time and the melting point of the substance used in the image-receiving layer. The temperature is preferably about 45° C. or higher, more preferably about 45° C. or higher. The composition of the image-forming substance-containing layer in the present invention is as follows: binder 5
70% (multilayer), image forming substance 1 to 90% (weight ratio), particularly preferably binder lO to 30%
% (by weight) of the imaging substance, proportions of from 70% (overlapping ratio) are advantageous. If necessary, a substance that assists the transfer of the image-forming substance may be added to this material. In this case, it is preferable to use a substance with a melting point, such as a low melting point compound (melting point 45°C to 120°C) or a substance with a softening point 45°C to 120°C.
As a 120'C ammonium molecule compound, materials that can be used include thermally flexible physical materials known in the art such as waxes, higher alcohols, and higher fatty acids. Specifically, paraffins, carnauba wax, beeswax, ceresin wax, polyethylene wax, etc. are used singly or in combination, taking their melting temperatures into consideration. In the non-inventive thermal transfer recording medium, the image-forming substance 7
An intermediate layer may be provided between the layer and the image-receiving layer. The intermediate layer may or may not melt when heated. In the former case, the image can be transferred to the transfer medium together with the image-receiving layer. In the latter case, ii! The condition is that the TI image-receiving layer must not be prevented from receiving the imaging substance. One method of using the thermal transfer recording medium of the present invention: Using a tool that can generate heat, such as a thermal knife, a thermal pen, or an iron. It is preferable to heat it from By using the thermal transfer recording medium of the present invention, various types of
An image can be recorded on a transfer medium such as paper such as -1 paper or a resin film such as polyethylene terephthalate film. In the thermal transfer recording medium of the present invention, the image-forming substance-containing layer and the image-receiving layer can be coated on the support as follows. First, to apply the image-forming substance-containing layer, for example, the image-forming substance is dissolved or dispersed in a solution containing the binder, or the binder is heated and melted without using a solvent. This can be carried out by dissolving or dispersing the image forming substance in a liquid and applying this solution onto a support using a commonly known coating device such as a wire bar, brush, or coater. At this time, in order to improve the adhesion between the support and the image-forming substance-containing layer, a so-called subbing layer may be applied between the support and the image-forming substance-containing layer. A preferred example of the thermal transfer recording medium of the present invention is as follows. In other words, by using a thermal head, thermal pen, laser beam, etc., depending on the heating temperature and heating time, li! ! i The image forming substance is removed from the image forming layer 41 by phenomena such as diffusion, elution, evaporation and sublimation.
Shift to the J-image response group. At this time, the image forming substance may migrate together with the low melting point compound contained in the image forming substance containing layer. The binder of the image-forming substance-containing layer is not transferred onto the transfer medium, but only the image-forming substance and the vUJJ image-receiving layer, which has migrated as a function of thermal energy, are transferred. Therefore, the optical density of the transferred recorded image according to the present invention is determined by the state of the image-forming substance transferred to the image-receiving layer. That is, when recording an image using the thermal transfer recording medium of the present invention, not only can halftones be expressed by the area ratio of halftone dots, etc., but also the mechanism of so-called density modulation is not clear. A visible image is formed on the transfer recording medium surface by heating with a thermal pen or the like. Furthermore, in the thermal transfer recording medium of the present invention, ii, I
Since the I7 image-forming substance-containing layer and the image-receiving layer are coated separately, it has excellent storage stability. According to the present invention, recording rjJii! While uniform density can be obtained not only for li images but also for solid images over a wide area, when it comes to photographic images, fine 11!1gl! It has the advantage of providing Preferred embodiments of the present invention will be shown below, but the present invention is not limited to these embodiments alone. Example 1 While stirring a solution in which gelatin II was dissolved in 20 mt of water, 4.9'a'710 of azobenzene was added thereto while stirring the solution, and the solution was cooled to 50'C. This solution was kept at 50° C. and allowed to cool in a sand mill for 2 hours to obtain coating solution 1. Coating liquid 2 was prepared by dispersing beeswax 2I in 20 mJ of water according to the external enemy method described in JP-A-56-120393. Coating liquid 1 was applied onto polyethylene terephthalate with a thickness of 6 μm using a wire bar, and after drying, the thickness was 3.2 μm.
Coating liquid 2 is applied with a wire bar onto the dried layer containing the image forming substance 4i, and dried to obtain an image receiving layer 4r having a thickness of 2.4 μm. A thermal transfer recording medium of the present invention was obtained. The above-mentioned coated side of this thermal transfer recording medium was brought into close contact with the surface of plain paper, and the temperature was varied with an iron from the support side.
When heated for a second, an orange transferred image could be obtained on plain paper. The optical reflection density of this image was measured using a reflection densitometer (manufactured by Roku Konishi). At temperatures of 100°C, 120°C, and 150°C, the reflection densities were 0.20.0, 57.1.17, respectively. Fifth, in the present invention, the optical reflection density of the transferred image can be changed in accordance with the heating temperature. Example 2 N,N-dimethyl- instead of azobenzene in Example 1
A thermal transfer recording medium was obtained using the same method as in Example 1, except that 2y of m-nitroaniline was used. This sample was subjected to the same transfer method as in Example 1.Heating temperature of the iron and red transferred image Example 1
It was measured in the same way. Iron heating temperature 100℃, 120℃
℃ and 150℃, the optical reflection density of the transferred image is 0, 35, 0.82, 1.41, respectively, and as in Example 1, the thermal transfer recording medium according to the present invention has It can be seen that the optical reflection density of the transferred image can be varied. Comparative Example A mixture of Coating Solution 1 (20 g) obtained in Example 1 and Coating Solution 2 (20 I Lt) was coated on a 6 μm thick polyethylene terephthalate film using a wire bar, and dried to give a coating of 1 V and 3. A thermal transfer recording medium provided with a layer of 5 μm was obtained. The same transfer method as in Example 1 was applied to this thermal transfer recording medium. Iron heating temperature 100℃, 120℃, 150℃
℃, the optical reflection density of the transferred image is 0.51.
0.44.0.63, and it was not possible to change the optical reflection density of the transferred image in response to the heating temperature. 4. Brief description of the drawings FIG. 1 shows a thermal transfer recording medium 4 and a transfer medium 5 of the present invention.
and heating device 6-f. Furthermore, 1°2 and 3 represent a support, an image-forming substance-containing layer, and an image-receiving layer, respectively. Agent Suna Kuwahara Beautiful procedural amendment ↑, Participant 11 Kazuo Wakasugi Tono 1 Naka I 1 C) l (Small Ill'i Japanese 57 乍Special revised application No. 175138 No. 2 Name of the invention Thermal transfer recording medium: ) Supplement i1. k I and 'If relationship 11f WT applicant 41 Location: Nishi-Shinjuku, Nishi-Shinjuku, Shin-i 6th Ward, Tokyo]] [126-2
1 Name (+27) Konishi Rokusha Tei 1-Gyo Co., Ltd.
Tonoki ηf Nobuhiko Kawamoto 4 Agent 191 L, 'r N11 7, Sakura-cho 1, No-shi, Tokyo 11 Contents of the amendment Correction as per the attached document Description 1 Name of the invention Thermal transfer recording medium 2 Patent Claims (1) A photosensitive material comprising an image-receiving layer that transfers the image-forming substance to a recording medium by heating, which is coated adjacent to the image-forming substance-containing layer containing the image-forming substance. Thermal transfer recording medium. (2) Claim 1, characterized in that an image-forming substance-containing layer is coated on a thermally stable support, and an image-receiving layer is coated directly or indirectly on the surface of the layer. Thermal transfer recording medium described in . 3. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel thermal transfer recording medium that forms a transferred image with rich gradation expression and which cannot be tampered with on the transferred recording medium. Conventionally, thermal transfer recording media, which are used to transfer and form images on plain paper using thermal printers, thermal facsimiles, etc., have been produced using heat-melting substances or sublimation dyes containing pigments that are melted onto the transfer recording medium by heating. ,sublimation,
Alternatively, a method in which an image is formed by volatilization is known. Also, a method has been reported in which a color forming agent and a color developer are added to a heat-melting material to develop and transfer color when heated. However, when using sublimable dyes, the dye density of the transferred image may change from moment to moment not only before recording but also after recording due to the dye's sublimation properties, resulting in poor storage stability. there were. In addition, the method of transferring by heating a heat-melting substance containing pigments, etc. has excellent storage stability, but on the other hand, the optical reflection density of the transferred image changes based on the change in the amount of image-forming substance per unit area of transfer. The essential drawback is that it is not possible to perform gradation expression. The heat-sensitive transfer recording medium containing a color former, color developer, etc. described in JP-A No. 56-120393 has a color former and a color developer contained in the same layer. Towash, light,
It has the disadvantage that it easily develops color when exposed to acids, alkalis, pressure, etc., and has poor storage stability. Therefore, the first object of the present invention is to provide a thermal transfer recording medium that can control the optical reflection density of a transferred recorded image as a function of heating temperature and obtain an image with rich gradation reproduction that cannot be tampered with. It is to provide. A second object of the present invention is to provide a thermal transfer recording medium that has good storage stability and does not generate unnecessary transferred images due to pressure or the like before heating recording. For this purpose, a layer containing an image-forming substance capable of forming an image by heating (hereinafter referred to as an image-forming substance-containing layer) is sequentially formed on a support, and a layer that receives the image-forming substance and is coated by heating. An image-receiving layer that can be transferred to a transfer medium (
Hereinafter, it will be referred to as an image-receiving layer. ) has been found to be achieved by a heat-sensitive transfer recording medium characterized by being coated with. Supports that can be used in the present invention include paper, plastic, metal, and other supports that do not soften when heated for a short time at a heating temperature of 100°C, where the image-forming material transfers to the image-receiving layer and is transferred to the transfer recording medium. In particular, any material that does not soften when heated for a short time at about 200° C. or less may be used, and condenser paper, polyethylene terephthalate film, and aluminum foil are particularly preferably used. Their thickness (
can be determined depending on the material of the support, but in general, if the thickness is 3 μm or less, it is difficult to coat a layer containing an image forming substance of 1 il, and if the thickness is 1011 m or more, it is disadvantageous in terms of ship efficiency. 3~40μ7n is good for one spring. In the thermal transfer recording medium of the present invention, it is possible to form an image on the surface of the recording medium. Imaging substance present in this layer 1+”=7Jl]
When heated, this layer may be coated with a substance that assists in the transition (for example, as a filter binder).
Casein, 4-palatin, polyvinyl alcohol, polyvinyl butyral, methylcellulose, gum arabic, polyester, polyvinyl formal, holipropylene,
Thermal stability with commonly known binding agents such as poly-f-rene, polyvinyl chloride, etc.1. C is preferred. When the image-forming substance contained in the image-forming substance-containing layer according to the present invention is heated to 45° C. or higher, it melts, evaporates, or sublimates itself, and forms an image by the action pressure of the transfer auxiliary substance present in the image-forming substance-containing layer. Any substance may be used as long as it can migrate to the receptor layer. For example, those having a melting point of 459C to 120C, such as azobenzene derivatives, nitrobenzene derivatives, thiophenol derivatives, and aniline derivatives, are preferably used. Particularly preferred are azotoluene, azobenzene, azopheneto-/l/, N,N-dimethyl-m-nitroaniline, p-nitroanisole, m-aminobenzophenone, p-aminobenzophenone, p-
Nitron-N, N-dimethylanilide, 4-nitro-2
-aminoanisole, nitrophenylhydrane, p-
Nitrobenzyl acetate is mentioned. Therefore, the heating temperature when heating the thermal transfer recording medium according to the present invention for transfer recording can be determined by taking into consideration the relationship with the heating time and the melting point of the substance used in the image-receiving layer. The temperature is preferably at least room temperature, more preferably at least about 45°C. The composition of the image-forming substance-containing layer in the VC of the present invention is as follows: binder: 5 to 70 parts (weight ratio), image forming substance: 1 to 90 parts (gold: 1).
The binder is preferably in the range of 10 to
A proportion of 30 parts (by weight) and 70 to 90 parts (by weight) of imaging material is advantageous. A transfer auxiliary substance for assisting the transfer of the image-forming substance may be added thereto, if necessary. The substance forming the image-receiving layer in the thermal transfer recording medium of the present invention is preferably a substance that is solid at room temperature and has a melting point capable of melting rock when heated, such as a low melting point compound (melting point 45°C to 120°C). ) Also, the softening point is 45°C ~ 1
Materials that can be scaled at 20° C. for polymeric compounds include thermoflexible materials such as waxes, higher alcohols, and higher fatty acids known in the art. Specifically, paraffins, carnauba wax, beeswax, ceresin wax, polyethylene wax, etc. are used singly or in combination in consideration of their melting temperature. In the thermal transfer recording medium of the present invention, an intermediate layer can be provided between the image-forming substance-containing layer and the image-receiving layer. The intermediate layer may or may not melt when heated. In the former case, the image can be transferred to the recording medium together with the image-receiving layer. In the latter case, the condition is that the image-receiving layer must not be prevented from receiving the image-forming substance. One method of using the thermal transfer recording medium of the present invention is to heat the support from the side on which the image-forming substance-containing layer is not coated using a device that can generate heat, such as a thermal head, thermal vane, or iron. It is desirable to do so. Using the thermal transfer recording medium of the present invention, it is possible to record the entire transferred image on a transfer recording medium such as various coated papers, papers such as drawing paper, and resin films such as polyethylene terephthalate film. In the thermal transfer recording medium of the present invention, the image-forming substance-containing layer and the image-receiving layer can be coated on the support as follows. First, to apply the image-forming acid substance-containing layer, for example, a solution in which the K1iii image-forming substance is dissolved or dispersed in the U liquid containing the binder, or a binder is heated without using a solution. An image-forming substance is dissolved or dispersed in a molten material, and this liquid is coated onto a support using a commonly known coating device such as a wire bar, brush, or coater. At this time, a so-called subbing layer can be applied between the support and the image-forming substance-containing layer to improve adhesion between the support and the image-forming substance-containing layer.The present invention A preferred example of a thermal transfer recording medium is as follows: An image forming substance is diffused, eluted, evaporated, or The image forming substance is transferred from the image forming substance containing layer to the image receiving layer by a phenomenon such as sublimation. At this time, the Ii!ili image forming substance may be transferred together with the low melting point compound R contained in the image forming substance containing layer. The binder of the image-forming substance-containing layer on the transfer recording medium is not transferred, but only the image-forming substance and the image-receiving layer that have migrated as a function of l/(7 thermal energy. Therefore, the transfer according to the present invention The optical reflection density of a recorded image is determined by the value of the image forming substance transferred to the image-receiving layer.That is, when recording a transferred image using the thermal transfer recording medium of the present invention, , it has the advantage that not only can the intermediate layer be expressed by the area ratio of halftone dots, etc., but also that the entire intermediate layer can be expressed by so-called dark-to-black modulation.
Although the mechanism by which the image-forming substance transfers to the I7 image-receiving layer is not clear, a visible image is formed on the surface of the transfer recording medium by heating with a thermal pen or the like. Furthermore, in the thermal transfer recording medium of the present invention, since the image-forming substance-containing layer and the image receiving layer 1- are coated separately, it has excellent storage stability. According to the present invention, recording ii! While uniformity can be obtained not only for 17 images but also for solid images over a wide area, it also has the advantage of producing a gradation of approximately 17 + 1 for photographic images. Preferred embodiments of the present invention will be shown below, but the present invention is not limited to these embodiments. Example 1 A solution in which 1 g of gelatin was dissolved in 20 cups of water was stirred at 10° C., 4 g of azobenzene was added thereto, and the solution was cooled to 50° C. This solution was dispersed in a sand mill for 2 hours while being maintained at 50° C. to obtain coating solution 1. Coating liquid 2 was prepared by dispersing 2 g of beeswax in 2 Q ml of water according to the dispersion method described in JP-A-56-120393. Coating liquid 1 was applied onto polyethylene terephthalate with a thickness of 6 μm using a wire bar, and after drying, the thickness was 3.2 μm.
A layer containing an imaging material was provided. Coating liquid 2 was applied onto the dried layer containing the image-forming substance using a wire bar and dried to obtain the entire image-receiving layer with a thickness of 2.4 μm, thereby obtaining a heat-sensitive transfer recording medium of the present invention. When the coated side of this thermal transfer recording medium was brought into close contact with the surface of plain paper and the temperature was varied with an iron from the support side for 1 second each time, an orange transferred image could be obtained on the plain paper. . The optical reflection of this image was measured using a degree P reflection density needle (manufactured by Roku Konishi). When the temperature was 100°C, 120°C, and 150°C, the reflected acidity was 0.20.0.57.1.17, respectively. In this way, in the present invention, the total optical reflection density of the transferred image can be changed in accordance with the heating temperature. Example 2 N,N-dimethyl-m instead of azobenzene in Example 1
A thermal transfer recording medium was obtained using the same method as in Example 1 except that -nitroaniline 29 was used. This sample was subjected to the same transfer method as in Example 1, and the heating temperature of the iron and the optical reflection density of the red color transfer density were measured in the same manner as in Example 1. Iron heating temperature 100℃, 12
At 0°C and 150°C, the optical reflection density of the transferred image is 0.35, 0.82, and 1.41, respectively, and as in Example 1, the thermal transfer recording medium according to the present invention corresponds to the heating temperature. It can be seen that the optical reflection density of the transferred image can be changed. Comparative Example A mixture of 20 ml of coating M1 obtained in Example 1 and 20 ml of coating liquid was applied with a wire bar onto a 6 μm thick polyethylene terephthalate film, and dried to form a 3.5 μm thick layer. A thermal transfer recording medium was obtained. The same transfer method as in Example 1 was applied to this thermal transfer recording medium. , iron heating temperature 100℃, 120℃, 15
At 0°C, the optical reflection density of the transferred image is 0.51.
．． The optical reflection density of the transferred image could not be changed in response to the heating temperature, which was 0.44.063. 4. Brief Description of the Drawings FIG. 1 shows a thermal transfer recording medium 4, a transfer recording medium, and a heating device 6 of the present invention. Furthermore, 1.2.3 represents a support, an image-forming substance-containing layer, and an image-receiving layer, respectively. Agent Yoshimi Kuwahara 553-

Claims (1)

[Claims] A layer containing an image-forming substance capable of forming an image by heating, and an image-receiving layer capable of receiving the image-forming substance and transferring it to a transfer medium by heating are coated on the support in sequence. Features of thermal transfer recording media.