JPS6225090A - Thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To prevent bleeding of the constituent of a recording medium, by forming cure layers at the side faces of a thermal transfer recording medium. CONSTITUTION:Cure layers 3 of active radiation curing substance are formed at the side faces 2, 2' of a thermal transfer recording medium 1. As the active radiation curing substance, any substance to be cured by the irradiation of an active radiation such as light or electron rays can be used, but the substance of silicon series is prefered. In this manner, even with the recording medium wound into a roll, bleeding of the constituent therein can be effectively prevented, and further defects caused by the deterioration of the medium, due to bleeding, contamination of a thermal head, malfunction of the feed of the recording medium can be prevented. As the thermal transfer recording material, a recording medium of hot melt transfer type is desired, especially a melting- type material containing wax with a 50-85 deg.C melting point is more effective.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to thermal transfer recording media.

C. Prior Art] In recent years, with the rapid development of the information industry, various information processing systems have been developed, and recording devices and methods suitable for each information system have also been developed and adopted. As one such recording method, the thermal recording method has recently been widely used because the device used is lightweight, compact, noiseless, and has excellent operability and maintainability.

However, the back of the recording paper used in the thermal recording method, normal thermal recording paper, is a color-forming processed paper that contains a coloring agent and a color developer, so it is expensive, and the recording can be tampered with.
The recording paper has disadvantages in that it has poor storage stability, such as being easily colored by heat or organic solvents and fading in a relatively short period of time.

A thermal transfer recording method has recently been attracting particular attention as a method that maintains the advantages of the above-mentioned thermal recording method and compensates for the drawbacks associated with the use of thermal recording paper.

This heat-sensitive transfer recording method generally uses a heat-sensitive transfer material made by melt-coating a heat-transferable ink made of a heat-melting binder with a colorant dispersed on a sheet-like support. The F1 transferable ink layer is superimposed on the recording medium so as to be in contact with the recording medium, and heat is supplied from the support side of the thermal transfer material by a thermal head to transfer the melted ink layer to the recording medium. A transfer ink image corresponding to the heat supply shape is formed thereon. According to this method, it is possible to maintain the above-mentioned advantages of the heat-sensitive recording method, use plain paper as a recording medium, and eliminate the above-described disadvantages associated with the use of heat-sensitive recording paper.

However, this thermal transfer recording method also has some problems that should be improved. One of these is the storage stability of recording media. Recording media are usually wound into rolls and made into cassettes. If this rolled recording medium is left at high temperatures, components of the recording medium will ooze out from the roll, causing problems such as deterioration of the recording medium, contamination of the thermal head by the oozing components, and poor feeding of the recording medium. Occur. As a method of preventing this bleeding phenomenon, it is possible to increase the melting point of the components of the recording medium or to remove low melting point impurities. However, these methods result in a decrease in recording sensitivity or an increase in the price of the recording medium.

[Problem that the invention seeks to solve]

The problem to be solved by the present invention is to eliminate the drawbacks of the above-mentioned conventional thermal transfer recording media. That is, the objective is to eliminate problems such as bleeding of components of the recording medium, deterioration of the medium due to this, contamination of the thermal head, and poor supply of the recording medium.

[Means for solving problems]

The above problem can be achieved by forming a cured layer of an actinic radiation-curable material on the side surface of a thermal transfer recording medium. More specifically, as shown in Figure 1, conventional thermal transfer recording media (1)
A cured layer (3) of an actinic radiation-curable material is formed on the side surfaces (2) and (2') of the substrate.

However, in FIG. 1, (4) is the base material, and (5) is the ink sheet layer.

[Effect]

In the present invention, the side surfaces (2) and (2') of the thermal transfer recording medium are
) is formed with a cured layer of active radiation-curable material, so even if the recording medium is rolled up,
It is possible to effectively prevent the component from oozing out from the roll, and in turn, the above-mentioned problems caused by this oozing can be prevented.

The actinic radiation-curable substance used in the present invention may be any substance that can be cured by irradiation with active radiation such as light or electron beams. Particularly preferred are silicon-based materials. As a specific example of this silicon-based material, for example, JP-A-53-5536
No. 3, JP-A-54-48854, JP-A-54-500
Ultraviolet curable silicone containing a double bond such as an allyl group or a vinyl group or a -5H group as disclosed in No. 67, etc., or JP-A-59-64669 and JP-A-59-6467.
Examples include electron beam-curable silicone disclosed in No. 0 and the like. The structural formulas of typical examples of these silicon-based materials are shown in the table below. However, the axis in the table below represents CH3, and ph represents a phenyl group.

In the present invention, ordinary photosensitizers and polymerization initiators can be appropriately added to these actinic radiation-curable substances. As the photopolymerization initiator in this case, a wide variety of initiators that have been conventionally used in this field can be used, such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzophenone, anthraquinone, acetophenone, anthracene, Examples include diphenyl disulfide and hensyl dimethyl ketal.

The ratio of these polymerization initiators used is usually 0.01 to 1 part by weight of the polymerization initiator per 100 parts by weight of the active radiation-curable substance.
Approximately 1 copy of 0ftf is used.

Various conventionally known materials can be used as the thermal transfer recording material in the present invention, such as thermal sublimation transfer disclosed in JP-A-59-101399 and JP-A-59-199295. Recording material, JP-A-56-8
Examples include thermal transfer recording materials that can be used multiple times and are disclosed in Japanese Patent Application Laid-Open No. 57-160691 and the like. Particularly preferred are heat-melt transfer recording media, which are composed of pigments, wax, cedar (fat, etc.).More specifically, polyethylene terephthalate film, polyethylene terephthalate film,
2-15μm of polyimide film, capacitor paper, etc.
A wax selected from waxes such as paraffin wax, microcrystalline wax, oxidized wax, carnauba wax, beeswax, esterified wax of montanic acid, acid wax, etc., and polyethylene, ethylene-vinyl acetate copolymer are placed on the thin heat-resistant film. , ethylene-7-1JJL41 ester copolymer, polystyrene, and other resins, carbon black as a coloring component, and an organic pigment listed in the Dye Handbook. The proportions of the socks, resin, and coloring components to the ink components are preferably such that the wax is 40 to 90% of the ink, the resin is 0 to 30%, and the coloring component is 5 to 25%.

As the thermal transfer recording material of the present invention, a heat-melting transfer type recording medium is preferable, but a melt-type type containing socks having a melting point of 50 to 85°C is particularly effective.

The means for forming a cured layer on the side surface of a thermal transfer recording medium using the actinic radiation-curable substance of the present invention is not particularly limited as long as this cured layer is formed. A typical method is to apply the above-mentioned curable substance, preferably a solvent solution thereof, from the side of the thermal transfer recording medium that has been partially rolled in a roll using an appropriate coating method such as a brush or spray. After drying, the material is cured by irradiating it with actinic radiation. At this time, the coating thickness of the cured layer of the active radiation curable substance is 1 to 50 μm.
That's about it. Further, as the solvent used in this case, a wide variety of solvents can be used as long as they can dissolve the actinic radiation-curable substance.

〔Example〕

The present invention will be explained below with reference to Examples. However, in the following examples, parts refer to parts by weight.

EXAMPLE An ink having the following components was coated on a polyethylene terephthalate film having a thickness of 3.5 μm to a thickness of 4.0 μm.

20 parts carbon blank 20 parts oxidized wax (mp 72°C) 25 parts paraffin wax (mp 69°C) 53 parts ethylene-vinyl acetate co-merge 2 parts The obtained film was heated to 81 WI
After cutting it to width II, it was wound 270 m around a core with a winding diameter of 1 cIm. The side surface of this rolled film was subjected to the curing treatment of the present invention as described below. That is, after adding 5% by weight of 2.4-dichlorobenzoyl peroxide based on tetramethyldivinyldisiloxane to a 10% toluene solution of tetramethyldivinylsiloxane,
It was applied to the side surface of the roll with a brush to a dry film thickness of 5 μm and air-dried. After air drying, it was irradiated with ultraviolet light using an ultraviolet lamp and cured.

Comparative Example A thermal transfer recording medium in which the curing treatment of the present invention was not performed at all in the above examples.

Each of the recording media of the above Examples and Comparative Examples was heated at 60°C and at a humidity of 40°C.
% for 2 hours, and then printed using a thermal printer. As a result, the product of the present invention had good printing runnability and quality with no ink smearing outside the roll, whereas the comparative product had ink seeping on the side of the roll. As a result, film feeding problems occurred during printing, and good printing could not be obtained.

[Brief explanation of the drawing]

FIG. 1 is a drawing showing an example of the thermal transfer recording medium of the present invention, in which (a) is a plan view of the same, and (b) shows the state in which it is wound into a roll. (1)・・・・・・・・・Thermal transfer recording medium (2), (
2')... Each side surface (3)... Cured layer of active radiation curable substance (4)... Base material (5)... ...Ink layer (and above) Patent applicant Nitto Electric Industry Co., Ltd. 10 (1) 711 Cori

Claims (4)

[Claims] (1) A thermal transfer recording medium characterized by having a hardened layer of an active radiation compound on its side surface. (2) The thermal transfer recording medium according to claim 1, wherein the thermal transfer recording medium is a thermal melt transfer type recording medium. (3) The thermal transfer recording medium according to claim 1, wherein the thermal transfer recording medium contains wax having a melting point of 50 to 85°C. (4) The thermal transfer recording medium according to claim 1, wherein the active radiation compound is a silicon-based active radiation compound.