JPH01125287A - Thermal transfer recording material - Google Patents

Abstract

PURPOSE:To obtain a thermal transfer recording material capable of effecting a high-quality printing on a recording paper with low smoothness even under low-energy and high-speed setting conditions and having good heat-build up properties by incorporating an encapsulated foaming agent containing therein isobutene in an ink layer. CONSTITUTION:In a thermal transfer recording material in which an ink layer composed of a foaming agent is heated by a heating means and is then melted to be transferred onto a paper for recording, thereby accomplishing recording, the foaming agent contains isobutene and is encapsulated. The failure temperature of the skin of the encapsulated foaming agent ranges from 55-280 deg.C, and the foaming agent is incorporated in the ink layer in an amount ranging from 0.1-35pts.wt. Thus, the thermal recording material so formed accomplices a high-quality printing on a recording paper with low smoothness even under low-energy and high-speed setting conditions.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a thermal transfer recording material with improved thermal transfer properties.

[Conventional technology]

In recent years, thermal transfer recording has been used in many fields such as facsimiles, computer terminals, and recorders due to its features such as non-impact, noiseless, maintenance-free, low cost, size and weight, and color printing. .

In such a thermal transfer recording method, an ink layer is melted and transferred onto a recording paper by heating the surface of the recording material using a thermal head or by heating an energized heat-generating resistive layer using a current-carrying head.

However, this method also had some drawbacks.

When plain paper is used as the transfer paper, the transferability of this thermal transfer recording method is greatly influenced by the unevenness of the surface of the plain paper, the surface physical properties, the adhesive strength of the ink layer, the permeability, etc.

Particularly in the case of paper with large surface irregularities, the hot melted ink cannot penetrate into the fibers of the paper during printing and only adheres to the convex parts of the surface or the vicinity thereof, resulting in sharp edges of the printed image. Otherwise, part of the image may be missing, resulting in a decrease in printing quality. In addition, in order to improve printing quality, it is possible to use a heat-melting binder with a low melting point, but in this case, the heat-transferable ink layer becomes sticky even at relatively low temperatures, causing blocking, etc. This causes inconveniences such as a decline in storage stability and staining of non-printing areas of the recording material.

As a means to solve the above problem, for example,
-201893, a technology was devised in which a thermally decomposable blowing agent is contained in the ink layer, and the blowing agent components include inorganic blowing agents such as bicarbonate, carbonate, and azide compounds, and azo Techniques using organic blowing agents such as nitroso-based, nitroso-based, and sulfonyl hydrazide-based blowing agents have been known.

[Problem that the invention seeks to solve]

Therefore, in order to solve these conventional problems, the present invention
By containing a foaming agent with low energy and good foaming properties in the ink layer, the aim is to obtain a thermal transfer recording material that has good print quality even on recording paper with low smoothness and has excellent heat-generating melting properties. It is closed.

However, when printing with a thermal transfer recording material containing these foaming agents in the ink layer, it takes time for foaming to occur after heating, making high-speed printing difficult and difficult to obtain the desired amount of foaming. , which had the disadvantage of requiring high energy.

[Means for solving problems]

In order to solve the above problems, the thermal transfer recording material of the present invention melts an ink layer containing a foamed material using a heat generating means and transfers it to a recording paper to obtain a recording. is characterized by containing isobutane and being encapsulated.

Furthermore, the capsule outer skin breaking temperature of the foamed material is 55 to
It is characterized by a temperature range of 280°C.

Furthermore, the ink layer contains the foaming material in an amount of 0.1 to 35% by weight.

〔Example〕

Examples of the present invention will be described in detail below, but the present invention is not limited thereto. The foam material used in the present invention was one in which isobutane was encapsulated and encapsulated in a vinylidene chloride/acrylonitrile copolymer. The capsule shell breaking temperature of the foam material must be within the range of 55 to 280°C, preferably 60 to 150''C. If the temperature is less than 55°C, wax and resin constituting the ink layer will be destroyed. It is necessary to select a material that has low physical properties, such as a softening and melting temperature that is approximately equal to or lower than that of , which reduces storage stability and tends to cause blocking.

On the other hand, if the temperature exceeds 280°C, the foaming properties will be reduced, leading to a reduction in the transferability.

Further, the content of the blowing agent is suitably 1 to 35% by weight of O. If the content is low, the amount of foaming will be small, resulting in poor transferability to plain paper, whereas if the content is high, the content of other ink compositions will be reduced, resulting in poor transferability and the generation of voids. It becomes easy.

[Example 1] As shown in FIG. 1, a thermal transfer recording material having an ink layer 2 containing a foaming agent 3 was prepared. As the support 1, a polyethylene terephthalate film having a thickness of about 6 μm was used. The composition of the ink layer 2 was adjusted as follows, dispersed in a solvent, and dried using a wire bar to a thickness of 12 μm.
It was coated to a thickness of about m.

Ink - Carnauba wax 30 Parafine wax 25 (m, p, 60 to 62°C) Oleic acid 5-functional ethylene-vinyl acetate copolymer 10 Surpon plug 20 Foaming agent 10 The capsule shell breaking temperature of Foaming agent 3 is 70 ~100℃
A material containing isobutane with an average particle diameter of 10 μm and an average particle diameter of 40 μm after foaming was used.

[Example-2] Ink was prepared by dispersing the following composition in a solvent Example 1
Similarly, the ink N2 was coated on the support 1 so that the thickness after drying was about 12 μm.

Ink -0 Carnauba wax 35 Parafine wax 29.9 Oleic acid 5-functional ethylene vinyl acetate copolymer
10 Surpon crank 20 Foaming agent
0.1 The capsule shell breaking temperature of the foaming agent 3 is in the range of 70 to 100°C, and the average particle size is 1.
0 am, the average particle size after foaming was 40 μm, and one containing isobutane was used.

[Example-3] Create ink by dispersing the following composition in a solvent Example 1
In the same manner as above, the ink layer 2 was coated on the support 1 so that the thickness of the ink layer 2 after drying was about 12 μm.

Ink -0 Carnauba wax 20 Parafine wax 20 Oleic acid 3-engineered ethylene vinyl acetate copolymer 7 Servon black 15 Foaming agent
35 The capsule shell breaking temperature of the foaming agent 3 is in the range of 70 to 100°C, and the average particle size is 1.
A material containing isobutane with an average particle size of 0 μm and 40 μm after foaming was used.

[Comparative Example-1] A polyethylene terephthalate film with a thickness of 6 μm was used as the support 1, and the composition of the ink layer 2 was adjusted as shown below, dispersed in a solvent, and dried using a wire bar to a thickness of about 12 μm. I painted it to look like this.

Ink - Carnauba wax 30 Parafine wax 30 Oleic acid 5-functional ethylene-vinyl acetate copolymer 15 Servon black 20 The thermal transfer recording material prepared by the above method is shown in FIG.

[Comparative Example-2] Ink was prepared by dispersing the following composition in a solvent.
The ink layer 2 was coated on top using a wire bar so that the thickness of the ink layer 2 after drying was about 12 μm.

In 0 Carnauba wax 20 Parafine wax 15 Oleic acid 3-engineered ethylene-vinyl acetate copolymer 7 Servon black 15 Foaming agent 40 The capsule shell breaking temperature of Foaming agent 3 is 70 to 100°C
The average particle size is 10 μm, and the average particle size after foaming is 40 μm. I used one that contained isobutane.

[Comparative Example-3] Ink was prepared by dispersing the following composition in a solvent Support 1
The ink layer 2 was coated on top using a wire bar so that the thickness of the ink layer 2 after drying was about 12 μm.

Ink: O carnauba wax 30 Parafine wax 25 Oleic acid 5-functional ethylene-vinyl acetate copolymer 10 Surpon plug 20 Foaming agent 10 The above-mentioned foaming agent was one containing ammonium carbonate as a main component.

The thermal transfer recording material obtained as described above was printed on the following two types of recording paper with different Beck smoothness using a thermal printer.
Print quality was visually evaluated. Furthermore, the printing speed is 40cp.
s and 80 cps, and head voltages were 18V and 25V.

Shin, Be... Pa (sec Lancaster Bond Paper 6~8 Xerox 4024
25-30 evaluation results are shown in Table 1.

-Table 1- Note) O1Δ, × are evaluations that change stepwise from good to bad.

As is clear from the above results, by using the thermal transfer recording material according to the example of the present invention, it was possible to obtain transfer with good print quality on recording paper with low smoothness even under low energy and high speed printing conditions.

Further, FIG. 3 is a diagram showing the thermal transfer recording material of the present invention transferred onto a transfer paper having unevenness. As can be seen from the figure, the foaming agent 3 in the ink layer 2 heated by the thermal head 4
expands due to thermal decomposition and efficiently contacts the uneven surface of the transfer paper 5. When the support 1 is peeled off from the transfer paper 5, the transfer paper 5
The heated and melted ink 6 is transferred onto the surface.

〔Effect of the invention〕

As explained above, the present invention uses a thermal transfer recording material containing isobutane and an encapsulated foaming agent in the ink layer, so that it can be printed even under low energy and high speed printing conditions on recording paper with low smoothness. A thermal transfer recording material with good print quality and excellent heat generation properties can be obtained.

[Brief explanation of the drawing]

FIG. 1 shows a cross-sectional view of the thermal transfer recording material of the present invention. Second
The figure shows a comparative example. FIG. 3 is a diagram showing a state in which a thermal transfer recording material is transferred to a transfer paper of the present invention. 1...Support 2...Ink layer 3...Blowing agent 4...Thermal head 5...Transfer paper 6...Heat-melted ink 7...Platen and above Applicant Seiko Epson Corporation Company Figure 1 Figure 2

Claims (3)

[Claims] (1) In a thermal transfer recording material in which a recording is obtained by melting an ink layer containing a foaming agent as a component using a heat generating means and transferring it to recording paper, the foaming agent includes isobutane and is encapsulated. Features of thermal transfer recording material. (2) The capsule shell breaking temperature of the foaming agent is 55 to 28
The thermal transfer recording material according to claim 1, characterized in that the temperature is in the range of 0°C. (3) The thermal transfer recording material according to claim 1, wherein the foaming agent is contained in the ink layer in an amount of 0.1 to 35% by weight.