JPH03227286A - thermal transfer ink ribbon - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a thermal transfer ink ribbon used in a heat-melting type thermal transfer printing device.

Conventional technology Conventional heat-melting type thermal transfer printing uses heat to change the viscosity of hoto-type ink, which uses wax, heat-melting resin, etc. as a binder, to adhere to or penetrate the transfer recording paper in contact with the ink. Then, by peeling the ink ribbon from the transfer recording paper, the ink is transferred to the transfer recording paper and printing is performed.

The thermal transfer characteristics of such hot-melt thermal transfer printing are mainly influenced by the surface conditions of the ink ribbon and the transfer recording paper. In particular, print quality is greatly affected by the composition and structure of the ink ribbon.

The thermal transfer ink ribbon used for hot-melt thermal transfer printing is
They can be roughly divided into two types: wax type ink with a high content of wax and low content of hot melt resin, and resin type ink with high content of hot melt resin and low content of wax 7.

The structure of a wax type ink ribbon is shown in FIG.

As shown in FIG. 4, the basic structure is that an ink layer 6 containing pigments, wax, thermofusible resin, etc. is provided on a base film 1, and a release layer 6 is provided between the base film 1 and the ink layer 6. Layer 2 may also be provided.

FIG. 5 shows the configuration of a north-south type ink ribbon. A release layer 2 made of wax, silicone resin, or fluororesin is provided on the base film 1, and an ink layer 3 made of a pigment, wax, heat-melting resin, etc. is provided on the release layer 2, and further A top coat layer 6 made of silicone resin, fluororesin, or the like is provided thereon. The reason why a top coat is provided in a resin type ink ribbon is to improve the lubricity between the heat-melting resin, which is largely contained in the ink layer 3, and the transfer recording paper. It is.

When performing thermal transfer on rough paper such as PPC copier paper with a rough surface (Beck smoothness of around 20 seconds) or bond paper (Peck smoothness of 10 seconds or less), use transfer recording paper that is difficult for the ink from the ink ribbon to come into contact with. Ink is transferred in the form of bridges in the recesses on the surface.

In order to prevent this bridge-like ink layer from breaking, a resin-type ink with a large self-cohesive force and a high melt viscosity is used.

Problems to be Solved by the Invention In general, wax-type ink ribbons require greater printing energy than resin-type ink ribbons because the heat of fusion of wax is greater.

Therefore, when printing is performed at low speed and with high printing energy, high quality printing can be obtained. However, high-speed printing is limited by the limit input energy of the recording head, resulting in insufficient input and extremely poor print quality.

In addition, in recent years, high-speed printing of 30 characters/second or more has become mainstream even in inexpensive serial type thermal transfer printing devices.
The use of resin-type ink ribbons, which are suitable for high-speed printing, is increasing. The ink surface of such a resin type ink ribbon is provided with a top coat layer made of silicone resin or fluororesin. Resin-type ink ribbons have a high resin content in the ink layer, so they have poor lubricity with the transfer recording paper, and the transfer recording paper is likely to be smudged due to friction between the paper and the ink ribbon. In order to prevent such scumming, the above-mentioned top coat layer is provided.

However, this top coat layer does not have good wettability with the transfer recording paper, so the adhesion between the ink and the transfer record is low, and good printing cannot be done on transfer recording paper with a rough surface such as rough paper. There was an issue.

The present invention solves these problems and provides a thermal transfer ink that improves the wettability of the ink of the resin type ink ribbon onto transfer recording paper and enables high-quality printing on everything from smooth paper to rough paper. The purpose is to provide ribbons.

Means for Solving the Problem In order to solve this problem, the present invention provides a resin type thermal transfer ink ribbon with the following configuration. That is, a release layer is provided on the base and the film, an ink layer containing a pigment, wax, and a hot melt resin is provided on top of the release layer, and a thin wax layer is further provided on top of that, and the surface of the ink layer does not contain wax components. The interior contains a large amount of resin components.

Function When performing thermal transfer with the above configuration, the adhesive force between the ink layer and the transfer recording paper is mainly determined by the wettability of the surface of the ink layer. Wettability is evaluated based on the contact angle of the surface of the ink layer with the surface of the transfer recording paper.

Table 1 shows the measurement results of the contact angle of various inks on transfer recording paper. As can be seen from Table 1, the contact angle of wax is smaller than that of resin, and its wettability is good.

Table 1 In the present invention, by applying wax on the ink layer without top coating with a release material, the wettability of the ink to the transfer paper is improved, and the adhesion between the ink and the transfer recording paper is improved. Power increases. Therefore, it is possible to always perform high-quality printing on smooth paper to rough paper without being affected by the surface condition of the paper.

Embodiment FIG. 1 is a structural diagram of a thermal transfer ink ribbon according to an embodiment of the present invention. As shown in FIG. An ink layer 13 made of a pigment such as carbon black, wax, and a thermofusible resin is provided on top of the ink layer 13, and a wax layer 14 is further provided on top of the ink layer 13.The surface is coated with wax and the inside is coated with a large amount of resin. The ink layer 13 contained in the ink layer constitutes a thermal transfer ink ribbon.

FIGS. 2 and 3 show thermal transfer results when the resin type ink ribbons of the present invention and the conventional resin type ink ribbon were transferred and recorded on rough paper with a rough surface. FIG. 2 shows the results of continuous recording of all dots using the ink ribbon of this example using a serial printer with a 48-dot thermal head under printing conditions of 70 characters/second. FIG. 3 shows the results of printing using a conventional resin type ink ribbon under the same conditions as FIG. 2.

As is clear from FIG. 2, the ink ribbon of the present invention was capable of high-quality printing even when transfer-recording was performed on rough paper, despite high-speed printing of 70 characters/sec.

The conventional example shown in FIG. 3 cannot keep up with high-speed printing, and the print quality deteriorates significantly. This difference, as shown in Table 1, is due to the strong adhesion between the ink and the paper, which is based on the excellent wettability of the wax layer used in the top coat in the configuration of the present invention.

Effects of the Invention As is clear from the above description of the embodiments, according to the present invention, the surface of the ink layer in the thermal transfer ink ribbon has a top coat layer made of wax, and the recording of the ink during thermal melting is improved. The contact angle to paper becomes smaller. As a result, the wettability of the ink improves and its adhesion to the recording paper increases, making it possible to print high-quality prints on everything from smooth to rough paper even when printing at high speeds such as 70 characters/second. can get.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the structure of a thermal transfer ink ribbon according to an embodiment of the present invention, FIG. 2 is a diagram of printed matter thermally transferred onto rough paper using the thermal transfer ink ribbon according to the embodiment, and FIG. 3 is a diagram of a conventional thermal transfer ink ribbon. FIG. 4 is a cross-sectional view showing the structure of a conventional wax-type thermal transfer ink ribbon, and FIG. 5 is a cross-sectional view of a conventional resin-type thermal transfer ink ribbon. 1... Base film, 2... Nm layer, s... Ink layer, 4. ,,,・Wax layer.

Claims (1)

[Claims] A release layer is provided on a base film, an ink layer containing a pigment, wax, and a thermofusible resin is provided on the release layer, and a wax layer is further provided on top of the ink layer, and the ink layer has a wax layer on the surface. A thermal transfer ink ribbon that contains a large amount of resin components.