JPH02128897A - Thermal transfer recording method - Google Patents

Abstract

PURPOSE:To enable a transmission image copy of an overheat projector (OHP) or the like to be easily prepared in a high density high clearly by a method wherein a thermal transfer ink donor sheet after transfer is used as an image recording material. CONSTITUTION:A thermal transfer ink donor sheet 4 of which on one side of a substrate 1 a thermal transfer ink layer 1 is provided and a thermal transfer ink acceptor ribbon 9 (corresponding to a transfer sheet of a conventional thermal transfer system) of which on one side an accepting layer 8 accepting the thermal transfer ink layer 1 or color material 3 is provided, are so piled that the thermal transfer ink layer 1 of the thermal transfer ink donor sheet 4 is opposed to the accepting layer 8 of the thermal transfer ink acceptor ribbon 9. Thermal transfer is performed by heating the thermal transfer ink acceptor ribbon 9 from an opposite side of a face on which the accepting layer 8 thereof 9 is provided with a thermal head 11. The thermal transfer ink donor sheet which is reversed to white after thermal transfer, i.e. since the color material of a part corresponding to an image is transferred, or the thermal transfer ink donor sheet in which the color material of parts other than the part corresponding to the image is transferred, is used as an image recording material.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is applicable to high-density thermal transfer images, especially overhead images.
The present invention relates to a thermal transfer recording method that allows a transparent image to be obtained using a projector (Ol-IP) or the like.

(Prior Art) In recent years, overhead projectors (hereinafter referred to as O
l-! (abbreviated as P) is frequently used.

With the spread of these OHP systems, various means have been adopted for image forming methods.

Additionally, there is an increasing demand for color images and higher density images. In order to meet these demands, it has become common to process characters and images using personal computers, word processors, etc., and to produce transparent image originals such as OHP using various printer devices as the output Ml.

Among these various types of printers used to create OHP transparent image originals, thermal transfer printers are easy to handle and maintain, make less noise during printing, and produce images with good gradation. It has the following characteristics.

There are two types of thermal transfer type printer devices: a sublimation type that uses a thermally sublimable dye as a coloring material, and a melting type that uses a thermally meltable binder and a pigment as a coloring material.

The principle of printing using these thermal transfer printers is as follows:
A thermal transfer recording sheet, which has a thermal transfer ink layer on one side of the substrate, and a transfer sheet are overlapped, and the thermal transfer ink layer or thermal transfer ink layer of the thermal transfer recording sheet is heated, for example, from the substrate side of the thermal transfer recording sheet by a thermal head of a printer device. The color material inside is thermally transferred to the transfer sheet.

(Problems to be Solved by the Invention) However, although the thermal transfer method is attracting attention as it exhibits the great features mentioned above, it still has a particularly big problem when applied to a recording medium having a transparent image such as an OHP. has been done. Unlike when thermally transferred onto a transfer sheet based on highly white paper or synthetic paper, when thermally transferred onto a transparent plastic film used for transmissive image originals such as OHP, the image recording density decreases. It is to be. Furthermore, a transparent image original such as an OHP whose image is observed using transmitted light requires a much higher density than a normal transfer sheet whose image is observed using reflected light.

Even in the thermal transfer method, in the melting type thermal transfer method, which uses pigment as the coloring material and a low melting point substance such as wax as the binder, the transferred ink layer itself has a low transmittance, making it difficult to obtain clear and high-density transmitted images. difficult.

Although the thermal transfer method has many advantages, it is difficult to create a high-density transparent original such as an OHP using the conventional method.

(Means for Solving the Problems) The present inventors have made full use of the features of conventional thermal transfer printers and have developed O-I, which is becoming widely popular.
Although efforts were being made to develop a recording medium that could obtain transparent images such as P with high density and clarity, the density of the ink layer itself provided on the thermal transfer ink donor sheet (corresponding to the transfer sheet in conventional recording media) It was thought that if it could be used in an image recording medium, the objective could be achieved by providing an ink layer in which a coloring material was dissolved or dispersed at a high concentration, and as a result of various studies, the present invention was completed.

That is, the present invention provides a thermal transfer ink donor sheet having a thermal transfer ink layer on one side of a substrate, and a thermal transfer ink acceptor ribbon having a thermal transfer ink layer or a receiving layer for receiving and receiving a coloring material on one side of the substrate (conventional thermal transfer transfer method). (equivalent to a sheet) such that the thermal transfer ink layer of the thermal transfer ink donor sheet and the receiving layer of the thermal transfer ink acceptor ribbon face each other, and from the side opposite to the surface on which the receiving layer of the thermal transfer ink acceptor ribbon is provided. Thermal transfer is performed by heating with a thermal head, and the thermal transfer ink donor sheet is treated as white because the color material in the area corresponding to the image has been transferred from the end of the thermal transfer, or the color material other than the area corresponding to the image has been transferred. This is a thermal transfer recording method characterized by using a transferred thermal transfer ink donor sheet as an image recording body.

In the conventional thermal transfer recording method, a color material or a thermal transfer ink layer is thermally transferred from a thermal transfer recording sheet (corresponding to the thermal transfer ink acceptor ribbon of the present invention) to a transfer sheet (corresponding to the thermal transfer ink donor sheet of the present invention), While the sheet serves as an image recording medium, the present invention is based on the completely opposite concept. For example, in terms of gradation, in order to obtain a transparent part of an OHP or other transmissive image with O (pyro) gradation, maximum thermal energy is applied through the thermal transfer ink acceptor ribbon, and the color in the ink layer of the thermal transfer ink donor sheet is Most of the material is thermally transferred to make it colorless and transparent.On the other hand, in order to obtain transparent image parts such as OHP with the highest degree of transparency, the ink layer itself is transferred without applying thermal energy, that is, without transferring the coloring material. It can be obtained by using as is. - In this way, high-density image recording bodies, which could not be achieved with conventional techniques, can be achieved by utilizing the thermal transfer ink layer itself containing the coloring material.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 is a diagram showing an embodiment of the thermal transfer recording method of the present invention. In the figure, 4 indicates a thermal transfer ink donor sheet (which itself becomes an image recording medium), 9 a thermal transfer ink acceptor ribbon, 10 a platen roller, and 11 a thermal head.

In addition, in the figure, 1 is a thermal transfer ink layer containing a coloring material, 2 is a thermal transfer ink donor sheet substrate that holds the thermal transfer ink layer 1, and 3 is a portion where the coloring material has been thermally transferred and the coloring material has escaped from the thermal transfer ink layer 1 ( color material transfer section). 5 is a receiving layer that receives the coloring material thermally transferred from the thermal transfer ink layer 1, and 8 is a thermal transfer ink! A portion (coloring material receiving portion) that receives the coloring material transferred from the coloring material transfer portion 3 of i11 is shown. 6 is a thermal transfer ink acceptor ribbon substrate that holds the receiving layer 5; 7 is a heat-resistant slippery material to prevent sticking with the thermal transfer ink acceptor ribbon substrate 6 due to heating from the thermal head 11 and to ensure running properties of the thermal head 11. It is a layer.

FIG. 2 shows the relationship between colored parts and non-colored parts of an image according to the present invention. For example, a case is shown in which an OHP transparent manuscript with characters "V II" is created. Desired characters II V n
To make one copy like a conventional thermal transfer image,
As shown in Figure 2 (b), the character 11 V! Areas other than the portion e are heated by the thermal head 11 to transfer the coloring material of the thermal transfer ink layer 1 to the receiving layer 5 of the thermal transfer ink acceptor ribbon 9. At this time, the thermal transfer ink layer 1 remains in the colored portion of the letter "V", making use of the high density property of the thermal transfer ink layer itself.The state of the thermal transfer ink acceptor ribbon 9 that has received this is shown in Figure 2. It becomes medium (d).

On the other hand, if you want the characters ``vI+'' to be treated as white in the colored part of the entire screen as shown in FIG. 2(a), only the white characters 11 It turns out. At this time, the thermal transfer ink layer remains as it is in the colored areas other than the white text 11V'' (the shaded areas in Figure 2 (a)), and the high density of the thermal transfer ink layer itself is produced, resulting in a very clear and beautiful color. An OHP transparent original can be obtained.The state of the thermal transfer ink acceptor ribbon 9 at this time is as shown in FIG. 2 (C), and the characters II V
rT is transferred to the coloring material and becomes a colored part. In the conventional thermal transfer recording method, since this image shown in FIG. 2(C) is used for the recording medium, the coloring density of the character 11 V $1 is not sufficient.

By the thermal transfer recording method as described above, it is possible to create a monochrome or monochrome transparent image original such as an OHP with a height of 211 degrees. Of course, it is also possible to take advantage of the gradation, which is a feature of the thermal transfer recording method.

FIG. 3 shows gradation with respect to thermal energy applied from the thermal head. In the figure, (a> shows the distribution of thermal energy with respect to gradation, and (b) shows the density on the thermal transfer ink donor sheet (recording body) of the present invention with respect to the given thermal energy (a).Thermal transfer ink donor To create white areas on the sheet, high thermal energy is applied, and conversely, to obtain high density colored parts, no thermal energy is applied at all.In Figure 3, the gradation shown in (C) becomes the conventional way of thinking.

Thermal transfer of the thermal transfer ink donor sheet 4 In the case of a sublimation type ink layer 1 using a sublimable dye, the transfer efficiency of the coloring material is increased and the residual rate of the coloring material in the ink layer after the coloring material is transferred. In order to lower the ink layer, increase transparency, and obtain clear images, it is desirable for the ink layer to have a high concentration and a thin thickness. Usually, the ink layer thickness is 0.1 to 10 μm, especially 0.1 to 10 μm.
1 μm is preferred. It is important to include as much coloring material as possible in such a thin ink layer.

Further, as the thermal transfer ink donor sheet substrate 2, OH
When creating a transparent image original such as P, a transparent plastic film such as a polyester film is used.

Usually, a thickness of 50 to 125 μm is used. Of course, an opaque material may be used as the thermal transfer ink donor sheet 4, as in the conventional thermal transfer recording system.

The thermal transfer ink acceptor ribbon 9 corresponds to a transfer sheet in a conventional thermal transfer recording system, but the thickness of the substrate is completely different. For the receiving layer 5, in the case of a sublimation type using a sublimable dye, a polyester resin having high dyeability is used. Thickness is usually 2-50μm1
Particularly preferred is 2 to 10 μm. The thermal transfer ink acceptor ribbon substrate 6 corresponds to a conventional thermal transfer ink ribbon substrate, and a sheet having a thickness of 3 to 9 μm is usually used.

Of course, a thin substrate provides high resolution and high sensitivity, but it is selected in consideration of ease of handling, process problems, durability, balance with the thickness of the receiving layer, price, etc.

As the base material, a plastic film such as a polyester film, capacitor paper, or glassine paper may be used. Further, in the case of a substrate without heat resistance, a heat-resistant slipping layer 7 is provided in order to impart heat resistance and, at the same time, ensure running properties of the thermal head. As the heat-resistant lubricant layer 7, a mixture of a heat-resistant resin and a lubricant such as silicone resin or fluororesin can be used.

Thickness is usually 0.1 to 5 μm, preferably 0.1 to 2 μm
It is. The thickness of this heat-resistant slipping layer 7 also affects resolution and sensitivity, so it is desirable that it be as thin as possible.

Next, embodiments of the present invention will be described in more detail.

A thermal transfer ink donor sheet 4 and a thermal transfer ink acceptor ribbon 9 having the configuration shown in FIG. 1 were prepared by the following method.

[Thermal Transfer Ink Donor Sheet] The following ink composition was coated on one side of a 100 μm thick polyester film as a base so that the thickness after drying was 1 μm.

Cyanide Color Set Blue 14 5 parts by weight (manufactured by Nippon Kayaku) Byron-2901 parts by weight (manufactured by Toyobo, linear saturated polyester resin) Ethyl cellulose 4 parts by weight Methyl ethyl ketone 40 parts by weight Torr
En 40 parts by weight Cyclohexanone 10 parts [Thermal transfer ink acceptor ribbon] The following receptor layer composition was applied on the opposite side of the heat-resistant slippery layer on the 6 μm thick polyester film provided with the heat-resistant slippery layer 7, after drying. A predetermined thickness was applied to the sea urchin to give a thickness of 5 μm.

1111 Ei 1 Byron-200151 Shinbe (manufactured by Toyobo, linear saturated polyester resin) Byron-3
0015 parts by weight (manufactured by Toyobo, linear saturated polyester resin) KS 8
41 12vffi parts (Shin-Etsu Chemical, silicone oil) Methyl ethyl ketone 34 parts by weight Torr
34 parts by weight The thermal transfer recording method of the present invention was carried out using the combination of the thermal transfer ink donor sheet 4 and the thermal transfer ink acceptor ribbon 9 thus obtained. The results are shown in Table 1. The comparative example is the result of a conventional method in which the cyan ink composition was provided on a 6 μm thick polyester film, the receiving layer composition was further provided on a 100 μm thick polyester film, and thermal transfer was performed using a combination of these.

(Hereinafter, blank space) Table 1 *1) Transmission density was measured using a Macbeth m meter TD-914.

2) Reflection density was measured using a Macbeth densitometer RD-918 on a white synthetic paper placed underneath.

As can be seen from this table, the thermal transfer recording method of the present invention makes it possible to obtain a transparent image recording medium such as an OHP having a higher density than the recording medium of the comparative example using the conventional thermal transfer recording method.

(Effects of the Invention) As described above, the thermal transfer recording method according to the present invention is particularly effective in the thermal dye sublimation transfer method, since the dye ink coating film originally possessed by the thermal transfer ink donor sheet has high density, clarity, and transparency. This makes it possible to utilize the good characteristics of the recording medium by leaving them as they are on the recording medium. As a result, it is possible to easily create transmissive image originals such as OHP with high density and high definition, which was not possible with conventional thermal transfer recording methods.
We can provide something that can be greatly utilized in presentations such as lectures.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the thermal transfer recording method of the present invention;
Fig. 2 is a diagram showing the relationship between the colored parts and non-colored parts of the image on the recording medium, and Fig. 3 is a diagram showing the density relationship of the colored parts of the ink donor sheet and ink acceptor ribbon with respect to thermal energy from the thermal head. be. DESCRIPTION OF SYMBOLS 1... Thermal transfer ink layer, 2... Thermal transfer ink donor sheet base, 3... Color material transfer part, 4... Thermal transfer ink donor sheet, 5...
Receptive layer, 6... Thermal transfer ink acceptor ribbon substrate, 7...
Heat-resistant slipping layer, 8... Coloring material receptor, 9... Thermal transfer ink acceptor ribbon, 1G... Platen roller, 11
...Thermal head. Patent Applicant: Victor Japan Co., Ltd. Representative: Kunio Umiki

Claims (1)

[Claims] A thermal transfer ink donor sheet having a thermal transfer ink layer on one side of a substrate and a thermal transfer ink acceptor ribbon having a thermal transfer ink layer or a receiving layer for receiving a colorant on one side of a substrate,
The thermal transfer ink layer of the thermal transfer ink donor sheet and the receiving layer of the thermal transfer ink acceptor ribbon are overlapped so as to face each other, and thermal transfer is performed by heating with a thermal head from the side opposite to the surface on which the receiving layer of the thermal transfer ink acceptor ribbon is provided. A thermal transfer recording method characterized in that the thermal transfer ink donor sheet after thermal transfer is used as an image recording body.