JPH06143845A - Thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To keep high printing density even when thermal transfer printing is repeatedly performed by providing a reticulated resin membrane on a hot-melt ink layer and providing vertical circular reticulated through-holes reaching the hot melt ink layer to the reticulated resin membrane. CONSTITUTION:In a thermal transfer recording medium 11, through-holes 6 are provided to the reticulated resin membrane 5 on a ink layer 4. As the resin of the reticulated resin membrane 5, a vinyl chloride/vinyl acetate copolymer is pref. By forming the through-holes 6 to the resin membrane 5, for example, a solution of the resin in methyl ethyl ketone is applied to the ink layer and the coating layer may be dried by air with relative humidity of 50% or more. By this constitution, it is prevented that the ink layer is peeled from a support 2 and the flow-out amt. of ink can be controlled at the time of thermal transfer recording.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermal transfer recording medium,
More specifically, the present invention relates to a thermal transfer recording medium in which a resin coating having a specific structure is provided on a heat-meltable ink layer so that a high-density image can be obtained by printing many times.

[0002]

2. Description of the Related Art Among recording devices such as printers and facsimiles, those utilizing a thermal transfer recording system have been widely used as devices which can be downsized, reduced in price, and reduced in maintenance. The thermal transfer recording medium used in the thermal transfer recording apparatus is generally one in which a thermal transferable ink layer (thermofusible ink layer) is simply provided on a support, and therefore the ink layer is heated by one use. There was a problem in running cost because the entire part was transferred to the receiving paper (plain paper etc.) and could not be used repeatedly. Therefore, the emergence of a thermal transfer recording medium that can be repeatedly used has been demanded, and various types of multiple-printing thermal transfer recording media have been proposed so far.

Some of them are (1) JP-A-54.
-68253, JP-A-55-105579, JP-A-60-40293, etc., a fine porous ink layer is provided on a support, and the heat-meltable ink is gradually added. It was made to exude, (2)
A method in which a porous film is provided on an ink layer on a support so as to control the outflow amount of ink, as disclosed in JP-A-58-212993, and (3) JP-A-60-127.
No. 191, JP-A-60-127192, etc., a plurality of ink layers are provided through a plurality of adhesive layers, and the adhesive layers and the ink layers are gradually peeled off to expose a new ink layer. Those that can be transferred and transferred are proposed. However, the thermal transfer recording medium of the above (1) has a drawback that it is difficult to seep out the ink with repeated use and the print density gradually decreases. In the thermal transfer recording medium (2), when the pore size of the porous film is increased in order to increase the printing density, the mechanical strength is lowered and the ink layer is peeled off. The thermal transfer recording medium (3) has a drawback that the transfer amount of the heat-meltable ink is not constant for each printing.

Further, most of the conventional thermal transfer recording media correspond to a serial thermal head used in a recording device such as a word processor, and like a line thermal bed used in a recording device such as a facsimile or a bar code printer. If the peeling time after heating the thermal transfer recording medium and the receiving paper (recording paper) is long, there is a drawback that the peeling of the ink layer occurs during peeling, and further, the image density decreases. Among the conventional techniques, in the thermal transfer recording mediums of (1) and (2), as disclosed in JP-A-63-137891, a thermosoftening resin is provided between the support and the ink layer. There is also proposed an example in which an intermediate adhesive layer is provided to prevent peeling of the ink layer. However, in this case, during thermal transfer recording,
In the multi-time thermal transfer recording medium in which the heat loss due to the intermediate adhesive layer is large and the ink coating layer is thicker than the one-time ribbon, the thermal sensitivity is remarkably reduced, and it is necessary to reduce the ink amount or increase the applied energy accordingly.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to prevent thermal peeling of an ink layer, maintain high printing density even when repeated thermal transfer printing is performed without increasing the applied energy, and reduce thermal density. A recording medium is provided.

[0006]

In the thermal transfer recording medium of the present invention, a thermofusible ink layer containing a thermofusible substance and a colorant as a main component is provided on a support, and a reticulated resin thin film is formed on the ink layer. In addition, the network resin thin film is further provided with through holes of circular mesh in the direction perpendicular or substantially vertical to the ink layer.

The other thermal transfer recording medium of the present invention comprises:
A heat-meltable ink layer containing a heat-meltable substance and a colorant as main components is provided on a support, and a reticulated resin thin film having a circular network penetrating in the vertical direction is provided on the ink layer The agent is scattered.

The present invention will be described in more detail below.
1 and 2 are schematic cross-sectional views of two typical examples of the thermal transfer recording medium according to the present invention. In the figure, 11 and 12 are thermal transfer recording media, 2 is a support, 3 is a heat resistant protective layer, 4 is an ink layer (thermofusible ink layer), 5 is a mesh resin thin film, and 6 is a through hole (vertical or almost vertical). In the drawing, through holes of a circular mesh that reach the ink layer 4 in the direction), and 7 represent release agents, respectively.

The thermal transfer recording medium 11 of the present invention shown in FIG.
In order to prevent the ink layer 4 from peeling off from the support 2 and to control the ink outflow amount at the time of thermal transfer recording, the network resin thin film 5 on the ink layer 4 is provided with through holes 6. As the resin of such a resin thin film 5,
Although a general thermoplastic resin can be used, a vinyl chloride-vinyl acetate copolymer, a polyester resin, a polycarbonate resin, a cellulose resin and the like are preferable.

To form the through holes 6 in the resin thin film 5, for example, the resin as described above is dissolved in a volatile solvent such as methyl ethyl ketone, and if necessary, water or an alcohol such as methanol or ethanol is added. , This solution is applied to the ink layer 4 by a normal coating method (wire bar coating method,
Gravure coating method, etc., and then relative humidity 5
It may be dried with air of 0% RH or more, preferably 60 to 80% RH.

The through hole 6 has a diameter of 0.01 to 10 μm, preferably 0.1 to 3.0 μm. 0.01μ
If it is smaller than m, the oozing of the ink may not be expected, and if it is larger than 10 μm, the oozing of the ink may be too large. It is appropriate that the through holes 6 have an interval between adjacent ones of 10 μm or less, preferably about 0.5 to 2.0 μm. If these intervals are larger than 10 μm, in the case of a solid printed image, the ink leached from the ink layer 4 through the through hole 6 cannot contact the ink from the adjacent through hole 6, and the transferred image is not printed. Dark astringency may occur. Further, the through hole 6
The number of is 30 to 300 per unit area (400 μm ² ),
It is preferably in the range of 50 to 150. The number of through holes 6 per unit area (400 μm ² ) is 3
If the number is less than 0, the ink from the ink layer 4 is less likely to seep out, resulting in a decrease in image density.
When the number of through holes 6 per m ² ) is larger than 300, the amount of ink seeping out from the ink layer 4 is increased, and the number of times of mulching is often extremely reduced.

The diameters of the through holes 6, their intervals, the number of the through holes 6 per unit area, etc. can be controlled by adjusting the relative humidity of the air during drying of the reticulated resin thin film, as described above. Control becomes easy by the amount of water or alcohol added to the coating solution of the resin thin film.
The coating amount of the resin thin film 5 is 0.02 to 0.50 g / m ²
(Thickness of the resin thin film 5 is 0.02 to 0.50 μm). If it is less than 0.02 g / m ² (or a thickness of 0.02 μm), the mechanical strength of the resin thin film 5 becomes weak,
Peeling of the ink layer 4 is likely to occur, and 0.50 g / m ²
(Or a thickness of 0.50 μm), the thermal sensitivity becomes low and an unclear image with low image density is obtained.

The thermal transfer recording medium 12 of the present invention shown in FIG.
The resin thin film 5 has a releasing effect on the receiving paper so that the entire ink layer is not transferred by one thermal transfer.
The release agent 7 is scattered on the top. That is, the resin used for the resin thin film 5 is a general thermoplastic resin, and since it is a thin film, when heat is applied from the thermal head, a part of the resin is softened and may be fixed on the receiving paper. In the worst case, the ink layer 4 is completely transferred to the receiving paper side. This phenomenon is particularly noticeable at low printing speed and high energy.

As the release agent 7, an inorganic lubricant is preferably used as the organic lubricant. As the organic or inorganic lubricant, beeswax, carnauba wax, spermaceti wax, wood wax, candelilla wax, nuka wax, montan wax, paraffin wax, polyethylene wax, oxidized wax, ozokerite, ceresin, ester wax and other natural waxes, petroleum wax, In addition to synthetic waxes, higher fatty acids such as margaric acid, lauric acid, myristic acid, palmitic acid, stearic acid, frommenic acid and behenylic acid,
Higher alcohols such as stearyl alcohol and behenyl alcohol, higher amides such as stearamide and oleinamide, organic lubricants such as esters such as glycerin and higher fatty acid esters of sorbitan, silica, calcium carbonate, talc, inorganic pigments such as kaolin, Fine particles such as fluororesin can be used. Among these, a particularly preferable mold release agent is one containing wax as a main component. This is because by using a wax as a main component as the release agent 7, when heat is applied from the thermal head, a part of the surface of the wax which is in contact with the receiving paper is melted and is more closely attached to the receiving paper. This is because a thermal transfer image with good resolution can be obtained. On the other hand, when the thermal transfer recording medium 12 is separated from the receiving paper, the release agent containing wax as a main component is solidified, so that it acts as a spacer.
It is considered that this is because the entire transfer of the ink layer 4 can be prevented. A wax-based release agent has a penetration of 25
By setting the temperature at 2 ° C. or less, it is possible to prevent transfer of the resin thin film 5 to the back surface, that is, so-called blocking phenomenon in a normal product state.

The scattered release agent 7 is preferably granular.
The particle size is 0.1 to 20 μm, preferably 3 to 10 μm. If it is smaller than 0.1 μm, the function as a spacer is impaired, and the entire transfer of the ink layer 4 easily occurs,
On the other hand, when it is larger than 20 μm, the adhesion to the receiving paper is deteriorated and the resolution is apt to be deteriorated.

Since the release agent 7 is scattered on the resin thin film 5 in the thermal transfer recording medium 12, the releasability from the receiving paper after thermal transfer recording is excellent, and the entire transfer of the ink layer to the receiving paper is prevented. However, it is preferable to impart adhesiveness to the support 2 to the ink layer 4 itself in order to prevent the entire transfer of the ink layer more reliably. This is
This is achieved by adding a substance having tackiness or adhesiveness to the ink layer 4 in contact with the support 2. Examples of the substance having tackiness or adhesiveness to the support 2 include polymer substances and wax-like substances, preferably polymer adhesives such as ethylene-vinyl acetate copolymer and microcrystalline wax. Can be mentioned. The addition amount of such a tacky or adhesive substance is appropriately determined according to the number of times of repeated printing and printing conditions, but in the case of application to a printer equipped with a normal line thermal head, in the case of a polymer adhesive, the ink 5 to 50% by weight in the layer, 5 to 70 in the ink layer in the case of microcrystalline wax
% By weight. In the case of a polymer adhesive, if the amount added is too large, the density of the transferred image will decrease, while if the amount added is too small, the adhesion of the ink layer 4 to the support 2 will decrease. In the case of microcrystalline wax, if the addition amount is too small, the adhesive force of the ink layer 4 to the support 2 is lowered, while if the addition amount is too large, problems such as blocking occur.

FIG. 3 shows the thermal transfer recording medium 11 shown in FIG.
The surface structure of was taken by a micrograph and examined. Further, FIG. 4 is a photograph of the surface structure of the thermal transfer recording medium 12 shown in FIG.

Further, in the present invention, two or more ink layers 4 are provided on the support 2 in order to enable high-density printing in a large number of times of thermal transfer, and the heat-meltable ink components of the ink layer 4 are melted. It is preferable that the ink layer having a higher viscosity be closer to the support 2. In this case, the melt viscosity of the ink layer can be adjusted by adding a thickener to the ink layer and appropriately selecting the type and addition amount of the thickener at that time. As the thickener, an adhesive or sticky substance that is solid at room temperature is used. Something like this:
In addition to various polymers, organic substances having a high melt viscosity such as the above-mentioned microcrystalline wax can be shown.
The thickener preferably used in the present invention is an ethylene-vinyl acetate copolymer, and particularly has a melt flow rate (MF) (JIS K 6760) of 10 g / 10 mi.
It is preferable to use one having an n or more, preferably 100 g / 10 min or more.

The thermal transfer recording medium of the present invention can be manufactured by a conventionally known method. That is, a predetermined ink layer 4 is formed on the support 2 (preferably a “heat resistant substrate”).
And the resin thin film 5 is formed thereon. Then, the through hole 6 is formed in the resin thin film 5. Further, if necessary, the release agent 7 is scattered so as to be embedded or adhered on the resin thin film 5.

The colorant forming the thermal transferable ink layer 4 is
Although it can be appropriately selected from known pigments and dyes, it is common to use carbon black or a phthalocyanine-based pigment as the pigment, and the dye is a direct dye, an acid dye, a basic dye, a disperse dye, or an oil. Soluble dyes and the like are generally used.

Vehicle components constituting the ink layer 4 include natural waxes such as beeswax, carnauba wax, whale wax, wood wax, candelilla wax, nuka wax and montan wax, paraffin wax, polyethylene wax, oxidized wax, ozokerite and ceresin. , Ester waxes and the like are generally used. In addition to these, higher fatty acids such as margaric acid, lauric acid, myristic acid, palmitic acid, stearic acid, flomenic acid and behenylic acid, higher alcohols such as stearyl alcohol and behenyl alcohol, stearamide and Higher amides such as oleinamide and esters such as higher fatty acid esters of glycerin and sorbitan are also used.

The coating amount of the thermal transfer ink layer 4 must be appropriately set in consideration of various factors such as the number of times of printing and thermal sensitivity, but generally, the dry weight of the entire thermal transfer ink layer is 4 to 12 g / m ² is good, and in the case of a two-layer structure, each layer is 2
˜7 g / m ^2, about 3 to 5 g / m ^{2 for} each layer.

As the support 2 used in the present invention, known heat-resistant materials such as plastic films of polyester, polycarbonate, triacetyl cellulose, nylon, polyimide, etc., cellophane, sulfuric acid paper, condenser paper and the like can be used. The thickness of the support 2 is preferably about 2 to 15 μm in consideration of heat sensitivity and mechanical strength.

Further, by providing a heat-resistant protective layer 3 made of silicone resin, fluororesin, polyimide resin, epoxy resin, phenol resin, melamine resin, nitrocellulose or the like on the surface of the support 2 which contacts the thermal head, the support 2 It is also possible to further improve the heat resistance of. A suitable thickness of the heat-resistant protective layer is about 0.01 to 2.0 μm.

[0025]

EXAMPLES Next, the present invention will be specifically described by way of examples. All parts and% herein are based on weight.

Example 1 (Coating liquid A) Carbon black 15 parts Lanolin fatty acid monoglyceride (mp = 73 ° C.) 25 parts Candelilla wax 20 parts Microcrystalline wax (mp = 83 ° C.) 30 parts Ethylene-vinyl acetate copolymer 10 Parts (melt flow rate: 2000 g / 10 min) After filling the above components in a sand mill vessel, the temperature was adjusted to 110
Dispersion was performed while maintaining the temperature at ℃ to obtain a heat-meltable ink component (coating liquid A).

(Application liquid B) Carbon black 10 parts Candelilla wax 40 parts Lanolin fatty acid monoglyceride (mp = 73 ° C.) 45 parts Ethylene-vinyl acetate copolymer (MF = 400 g / 10 min) 5 parts The above components are put into a sand mill vessel. After filling, the temperature is 110
Dispersion was carried out by keeping at ℃. 20 parts of this dispersion was crushed, added to 80 parts of methyl ethyl ketone / toluene (2/1) mixed solvent, dissolved by heating and then cooled and dispersed at 25 ° C. to obtain a heat-meltable ink component (coating liquid). B) was obtained.

(Coating liquid C) Vinyl chloride-vinyl acetate copolymer 3 parts Methyl ethyl ketone 94 parts Water 3 parts The above components were mixed to obtain a resin thin film component (coating liquid C).

Next, after applying A to the other surface of the substrate, which has been heat-treated on one side, a PET film having a thickness of about 5.5 μm is applied.
Is applied by the hot melt coating method to about 3 g / m
A thermal transfer ink layer of ² was obtained. Subsequently, the coating liquid B is applied with a bar coater and then dried at 80 ° C. to obtain about 4 g /
A m ² thermal transfer ink layer was laminated. The coating liquid C is also coated with a bar coater in the same manner, and then air having a relative humidity of 50% RH, a wind speed of 2 msec and a temperature of 20 ° C. is uniformly applied for 10 seconds and dried to laminate a resin thin film of about 0.2 g / m ^2. To prepare a thermal transfer recording medium. The cross section of this thermal transfer recording medium is T
Analysis by EM photographs and SEM photographs of the surface revealed that a resin thin film having through holes of circular mesh was formed. The diameter of the through hole is about 1.
5 μm, their spacing is about 2 μm, unit area (400 μm
The number of through holes per m ² ) was about 150. I was convinced.

Example 2 In Example 1, the coating liquid C was dried under the relative humidity of 80.
% RH, wind speed 2m / sec, temperature 10 ℃ 10
A thermal transfer recording medium was obtained in the same manner as in Example 1 except that it was uniformly applied for a second and dried. As a result, the diameter of the through holes of the formed resin thin film was about 3.0 μm, the distance between the through holes was about 3 μm, and the number of through holes per unit area (400 μm ² ) was about 100.

Example 3 Example 1 except that the composition of the coating liquid C was changed to the coating liquid D described below.
A thermal transfer recording medium was obtained in the same manner as in. As a result, the diameter of the through holes of the formed resin thin film was about 2.5 μm, the distance between the through holes was about 4 μm, and the number of through holes per unit area (400 μm ² ) was about 25. (Coating liquid D) Vinyl chloride-vinyl acetate copolymer 3 parts Methyl ethyl ketone 94 parts Methanol 2 parts Water 1 part

Example 4 In Example 3, the coating liquid D was dried under the relative humidity of 80.
% RH, wind speed 2m / sec, temperature 10 ℃ 10
A thermal transfer recording medium was obtained in the same manner as in Example 3 except that it was uniformly applied for a second and dried. As a result, the diameter of the through holes of the formed resin thin film is about 2.5 μm, and the distance between the through holes is about 1
The number of through holes per μm and unit area (400 μm ² ) was about 300.

Example 5 In Example 1, the composition of the coating liquid C was changed to the coating liquid E described below, and the drying conditions were 80% RH relative humidity and 2 m / se wind velocity.
A thermal transfer recording medium was obtained in the same manner as in Example 1 except that air having a temperature of 20 ° C. was uniformly applied for 10 seconds to be dried. As a result, the diameter of the through hole of the formed resin thin film is about 2.0 μm, the distance between the proposed holes is about 3 μm, and the unit area (4
The number of through holes per 00 μm ² ) was about 80. (Coating liquid E) Vinyl chloride-vinyl acetate copolymer 3 parts Vinyl chloride powder 2 parts (Average particle size of about 4.0 μm, Whiten SB manufactured by Shiraishi Calcium Co.) Methyl ethyl ketone 92 parts Water 3 parts

Example 6 In Example 1, the composition of the coating liquid C was changed to the coating liquid F described below, and the drying conditions were 80% RH relative humidity and 2 m / se wind speed.
A thermal transfer recording medium was obtained in the same manner as in Example 1 except that air having a temperature of 20 ° C. was uniformly applied for 10 seconds to be dried. As a result, the diameter of the through holes of the formed resin thin film is about 2.0 μm, the distance between the through holes is about 2 μm, and the unit area (4
The number of through holes per 00 μm ² ) was about 100. (Coating liquid F) Vinyl chloride-vinyl acetate copolymer 3 parts Paraffin wax aqueous dispersion (solid content 30%, average particle size about 3 μm) 8 parts Methyl ethyl ketone 91 parts

Example 7 In Example 1, the composition of the coating liquid C was changed to the coating liquid G described below, and the drying conditions were 80% RH relative humidity and 2 m / se wind velocity.
A thermal transfer recording medium was obtained in the same manner as in Example 1 except that air having a temperature of 20 ° C. was uniformly applied for 10 seconds to be dried. As a result, the diameter of the through holes of the formed resin thin film was about 2.0 μm, the distance between the through holes was about 2.0 μm, and the number of through holes per unit area (400 μm ² ) was about 120. (Coating liquid G) Vinyl chloride-vinyl acetate copolymer 3 parts Carnauba wax aqueous dispersion (solid content 30%, average particle size about 4 μm) 8 parts Methyl ethyl ketone 87 parts Methanol 2 parts

Comparative Example 1 The coating liquid C was dried under the conditions of relative humidity of 10% RH and wind speed of 2 m /
A thermal transfer recording medium was obtained in exactly the same manner as in Example 1 except that air having a temperature of 20 ° C. for 10 sec was uniformly applied and dried. As a result, no circular mesh through holes could be confirmed in the formed resin thin film.

Comparative Example 2 The composition of coating liquid C in Example 1 was changed to the following coating liquid H, and the drying conditions were 90% RH relative humidity and 2 m / se wind speed.
A thermal transfer recording medium was obtained in the same manner as in Example 1 except that air having a temperature of 20 ° C. was uniformly applied for 10 seconds to be dried.
As a result, in the formed resin thin film, some of the through holes were cut innumerably, and the film had low mechanical strength. (Coating liquid H) Vinyl chloride-vinyl acetate copolymer 3 parts Methyl ethyl ketone 74 parts Methanol 20 parts Water 3 parts

These 9 types of thermal transfer recording media were mounted on a line thermal head, and the same spot was printed 5 times under the following conditions. [Printing conditions] Thermal head: Line thin film head type (8dot /
mm) Platen pressure: 330 gf / cm Peeling angle of thermal transfer recording medium: 45 ° (to transfer paper) Applied energy: 18 mj / mm ² Printing speed: 4 inch / sec Transfer paper: coated paper (Bristow absorption 4. 00 ml:
j. TAPPI, No. 51, first grade liquid paraffin used / Beck smoothness 2000 sec) Printing pattern: CODE39 parallel bar coat (Na
print 2 dots) 4 solids (6 mm × 7 mm) printing environment temperature: 20 ° C., 60% RH The density of the solid portion of the printed matter was evaluated by RD-914 manufactured by Macbeth. The total transfer of the ink layer was visually evaluated. Regarding the image printing unevenness, the presence or absence of printing unevenness in the solid portion was visually evaluated. For blocking, the surface of each thermal transfer recording medium was superposed on the polyethylene terephthalate film so as to face each other, and left at 50 ° C. for 24 hours under a load of 2 kg / cm ² .
After cooling, it was visually confirmed and evaluated. The results are summarized in Table 1.

[0039]

[Table 1]

In Examples 1 to 4, excellent bar code reproducibility and relatively high image density up to 5 times printing were obtained. Above all, Example 2 was able to withstand practical use. In addition, in Examples 5 to 7, printed images with excellent bar code reproducibility and high temperature without image density unevenness were obtained. Among them, Example 7 was excellent in blocking resistance and was printed with a large number of times, which was extremely practical. It was a thermal transfer recording medium for use. In Comparative Example 1, only images with low density can be obtained, and in Comparative Example 2
However, the image density became low after the fourth time, which was not practical.

[0041]

According to the thermal transfer recording medium of the first aspect, a net-like resin thin film having a circular mesh penetrating in the vertical direction is formed on the uppermost layer to prevent the ink layer from peeling off from the base material (support). At the same time, the amount of ink outflow can be controlled during thermal transfer, and an image with high print density can be obtained. In the thermal transfer recording medium according to the second or third aspect, by setting the thickness of the uppermost layer or the coating amount within a certain range, the amount of ink flowing out from the ink layer becomes appropriate. The thermal transfer recording medium according to claim 4, 5 or 6 has a high printed image by defining the diameter of the through holes, the number of craters per unit area (400 μm ² ) in the point resin thin film or the distance between adjacent through holes. It is possible to achieve multi-time maintenance in concentration.
In the thermal transfer recording medium of the seventh aspect, the release agent is scattered on the resin film, whereby the entire transfer of the ink layer can be prevented. In the thermal transfer recording medium according to the eighth aspect, the release agent containing wax as a main component provides a clear image with excellent resolution, that is, less white spots. The thermal transfer recording medium according to claim 9 is further improved in blocking resistance by using a release agent containing a wax having a penetration of 2 or less at 25 ° C. as a main component.

[Brief description of drawings]

FIG. 1 is a sectional view of an example of a thermal transfer recording medium according to the present invention.

FIG. 2 is a sectional view of an example of another thermal transfer recording medium according to the present invention.

FIG. 3 is a micrograph showing a surface structure of a thermal transfer recording medium according to the present invention.

FIG. 4 is a micrograph showing the surface structure of another thermal transfer recording medium according to the present invention.

[Explanation of symbols]

 2 Support 3 Heat Resistant Protective Layer 4 Ink Layer 5 Resin Protective Layer 6 Through Hole 7 Release Agent 11, 12 Thermal Transfer Recording Medium

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Masahiro Sato 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd.

Claims (9)

[Claims] 1. A heat-meltable ink layer containing a heat-meltable substance and a colorant as a main component is provided on a support, a network resin thin film is provided on the ink layer, and a circle perpendicular to the network resin thin film. A thermal transfer recording medium, characterized in that through holes having a mesh shape are provided. 2. The thickness of the reticulated resin thin film is 0.02 to
The thermal transfer recording medium according to claim 1, which has a thickness of 0.50 μm. 3. The coating amount of the reticulated resin thin film is 0.02 to
The thermal transfer recording medium according to claim 1, which has a weight of 0.50 g / m ² . 4. The thermal transfer recording medium according to claim 1, wherein the diameter of the through hole is 0.01 to 10 μm. 5. The number of the through holes is 30 per 400 μm ^2.
2. The thermal transfer recording medium according to claim 1, wherein the number is from 300 to 300. 6. The thermal transfer recording medium according to claim 1, wherein the through holes have an interval between adjacent ones of 10 μm or less. 7. The thermal transfer recording medium according to claim 1, wherein a release agent is scattered on the reticulated resin thin film. 8. The thermal transfer recording medium according to claim 7, wherein the release agent contains wax as a main component. 9. The thermal transfer recording medium according to claim 8, wherein the release agent containing wax as a main component has a penetration of 2 or less at 25 ° C.