JPH0580355B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat-sensitive melt transfer recording medium for use in a heat-sensitive melt transfer recording method using a thermal head employed in computer printers, typewriters, and the like. More specifically, the present invention relates to a heat-sensitive melt transfer recording medium in which a heat-melt colored ink layer containing a heat-melt synthetic resin as the main component of the vehicle is provided on one side of a polyester film.

[Prior art and its problems] In this type of heat-sensitive melt transfer recording medium, it is possible to improve the printing performance on paper with a rough surface, or to re-apply the colored ink layer that has been image-wise transferred to the recording paper. By overlapping printing, it exhibits the ability to be peeled off and erased (hereinafter referred to as lift-off property),
A colored ink layer whose main component is an appropriate heat-melting synthetic resin in order to provide abrasion resistance so that the transferred print image on the recording paper does not wash away even when rubbed by a machine or fingers. has come to attract attention.

On the other hand, from the viewpoint of heat resistance and thickness, polyester films have been widely used as supports for this type of heat-sensitive melt transfer recording media. When a colored ink layer is formed as the main component, the ink adheres too much to the polyester film, and when heated with a thermal head, a portion remains on the film side, making it difficult to obtain a good printed image. There was a problem.

[Means for Solving the Problems] In order to solve these problems, the present invention has the following features:
A wax layer containing polyethylene wax as a main component is formed by applying and drying an aqueous dispersion of wax containing polyethylene wax as a main component on the surface of a polyester film, and the surface of the wax layer is In addition, the vehicle is composed of a heat-melting synthetic resin as a main component, and a colored ink layer containing no wax is provided.

[Function and Effects of the Invention] With the above configuration, the wax layer is melted well by heating with a thermal head, and a layer with weak internal cohesive force is formed between the colored ink layer and the polyester film. Although the colored ink layer has a strong internal cohesive force due to the vehicle, it is thought that only the areas heated by the thermal head are selectively transferred to the recording paper, and this causes the polyester It has now become possible to successfully transfer a colored ink layer containing a heat-melting synthetic resin as the main component of the vehicle while using a film as a support.

[Example] Next, the present invention will be specifically explained.

The polyester film used as the support has a thickness of 2 to 10 μm, and any conventionally known polyester film may be used.

The wax layer formed on the surface of the film is preferably coated with an emulsion in which wax containing polyethylene wax as a main component is dispersed in water, and the thickness after coating and drying is 2 to 3 g/ ^m2. It is preferable to

The colored ink layer, which has the heat-melting synthetic resin as the main component of the vehicle and does not contain wax, is a solvent that is liquefied using a volatile organic solvent that dissolves the vehicle, and then applied and dried on the surface of the wax layer. It is best to use the coating method.
The thickness of the colored ink layer after drying is 4 to 10 g/m ²
It is appropriate to keep it at a certain level.

The main component of the wax layer is polyethylene wax, and paraffin wax, carnauba wax, etc. may also be blended therein.

The heat-melting synthetic resin includes ethylene-vinyl acetate copolymer, polyamide resin, 1,2-polybutadiene, etc., and has a melting point of 50 to 90°C.
Melt index (measured by DSC) is 20
It is appropriate to use one with a yield of ~1000g/10 minutes (190°C).

Example 1 An aqueous emulsion in which 20% by weight of polyethylene wax (melting point 103°C) was dispersed was coated on the surface of a 3.5 μm thick Lumirror (polyester film manufactured by Toray Industries, Inc.) and dried to a thickness of 2 g/ ^m2. Added a wax layer.

A colored ink with the following formulation was applied to the surface of the wax layer using a solvent coating method and dried to a thickness of 7 g/
A colored ink layer of m ² was obtained.

Ethylene-vinyl acetate copolymer 4 parts by weight (vinyl acetate content 28% by weight, melting point 63°C, melt index 150g/10 minutes (190°C)) Carbon black 1 part by weight Toluene 20 parts by weight Obtained in this way Edge-type thermal head
When printing was carried out on recording paper with a Beck smoothness of 30 seconds using a recording paper (shown in FIG. 2 of Publication No. 179268), a clear printed image was able to be transferred and formed. Thereafter, this heat-melting transfer recording medium was placed on top of the printed image and heated by a thermal head with about 80% of the energy of the transfer, and the impression was removed from the recording paper.

Claims (1)

[Claims] 1. A wax layer containing polyethylene wax as a main component is provided on the surface of a polyester film by applying and drying an aqueous dispersion of wax containing polyethylene wax as a main component. A heat-sensitive melt transfer recording medium provided with a wax-free colored ink layer on the surface of which the main component of the vehicle is a heat-melt synthetic resin.