JPH0986056A - Thermal transfer recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermal transfer recording medium developing antibacterial properties by antibacterial fine particles precipitated on the surface thereof after transfer by successively laminating a release layer having an antibacterial agent added thereto and a color ink layer or the release layer having the antibacterial agent added thereto, the color ink layer and an adhesive layer on a base material. SOLUTION: A release layer 2 and a color ink layer 3 are successively laminated to one surface of a base film 1 and a sticking preventing layer 4 is laminated on the opposite surface thereof to form a thermal transfer recording material 5. The base film 1 is pref. composed of polyethylene terephthalate and the thickness thereof is about 2-9μm. The release layer 2 is formed by using wax as a main material and inorg. antibacterial agent fine particles of which the average particle size is twice or less the thickness of the release layer. A material used in the color ink layer 3 is cellulose derivative, a styrene resin or an acrylic resin and a dye or pigment is added thereto. As the inorg. antibacterial agent, silver or an inorg. substance having silver ions supported thereon is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer recording medium used for thermal transfer recording in which characters and images are transferred and recorded by a thermal head.

[0002]

2. Description of the Related Art In recent years, products containing antibacterial agents have been extensively developed. Examples thereof include ballpoint pens, pencils, notebooks, office supplies such as files, electrical products such as personal computers, word processors, and telephones, furniture such as chairs and desks, packaging films, and labels. However, there has been no example used at present in a thermal transfer recording medium. In addition, products with antibacterial agents that have been developed in recent years have been printed with a word processor, etc., or those with characters, pictures, etc. printed on them. And the antibacterial property of the product itself is impaired.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances. After the transfer by adding antibacterial fine particles to the release layer of the thermal transfer recording medium,
It is an object of the present invention to provide a heat-sensitive transfer recording medium capable of exhibiting antibacterial properties by exposing antibacterial fine particles to the surface.

[0004]

The heat-sensitive transfer recording medium of the present invention is a heat-sensitive transfer recording medium having a transfer layer on at least one side of a base material, which is used in a heat transfer recording apparatus having a thermal head, A peeling layer, a colored ink layer, or a peeling layer, a colored ink layer, and an adhesive layer are added, and an antibacterial agent is added to the peeling layer.

Further, the antibacterial agent is characterized in that it comprises an inorganic antibacterial agent having an average particle diameter not more than twice the thickness of the release layer.

Further, as the above-mentioned inorganic antibacterial agent, an antibacterial agent containing silver as an antibacterial component is used.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows one of the basic constitutions of the present invention. A peeling layer (2), a colored ink layer (3) from a base film (1), and an anti-sticking layer (4) on the opposite side. ) Is provided to form a thermal transfer recording medium (5).

FIG. 2 is also one of the basic constitutions of the present invention. A peeling layer (2), a colored ink layer (3), an adhesive layer (6) from the base film (1), and a sticking prevention layer ( 4) is provided to form a thermal recording transfer medium (7).

As the base film (1), a polyethylene terephthalate sheet having a thickness of about 2 to 9 μm is used.

The release layer (2) is mainly made of wax, but resin may be added in some cases. As wax, carnauba wax, rice wax, montan wax, microcrystalline wax, candelilla wax,
One or more of ceresin wax, paraffin wax, polyethylene wax and the like are used, and as a resin to be added, cellulose derivative, styrene resin, styrene copolymer resin, acrylic resin, methacrylic resin, rosin ester resin, polyvinyl acetate One or two of resin, polyvinyl chloride, vinyl chloride / vinyl acetate copolymer, ethylene / vinyl acetate copolymer, polyester resin, polyurethane resin, butyral resin, polyamide resin, petroleum resin, chlorinated rubber, chlorinated polyolefin resin The above is selected and used.

Inorganic antibacterial agent fine particles having an average particle diameter not more than twice the thickness of the peeling layer are added to the peeling layer (2). When the added antibacterial agent is printed by the thermal head through the heat-sensitive transfer recording medium, the antibacterial agent is exposed on the surface of the transfer paper to develop the antibacterial property. At this time, if the average particle size of the fine particles is larger than twice the release layer, it becomes difficult to form the release layer properly, and the performance as a recording medium cannot be obtained.

Materials used for the colored ink layer (3) and the adhesive layer (6) are cellulose derivative, styrene resin, styrene copolymer resin, acrylic resin, methacrylic resin, rosin ester resin, polyvinyl acetate resin, polyvinyl chloride. ,
One or more of vinyl chloride / vinyl acetate copolymer, ethylene / vinyl acetate copolymer, polyester resin, polyurethane resin, butyral resin, polyamide resin, petroleum resin, chlorinated rubber, and chlorinated polyolefin resin are used, but wax May be added. Carnauba wax as wax,
Rice wax, montan wax, microcrystalline wax, candelilla wax, ceresin wax, paraffin wax, polyethylene wax, etc.
One kind or two or more kinds are used. Solid fine particles may be added to improve sharpness during printing. As the wax, the above-mentioned wax is used, and as the fine particles, it is effective to use solid fine particles such as silica, silicone, benzoguanamine, and fluorine. A dye or a pigment may be added to the colored ink layer (3), and a colorant may be added to the adhesive layer depending on the case.

As the inorganic antibacterial agent that can be used in the present invention, those in which silver or silver ions are supported by an inorganic substance can be used. Inorganic antibacterial substances other than silver that can be used include copper and zinc, but copper has the same antibacterial activity as silver, but since it has hygienic problems, it is necessary to exercise caution when using it. Further, zinc has a problem that it has a poor antibacterial activity.

Examples of the carrier that holds these metals or metal ions include zeolite, clay minerals and silica. There are a dry pulverization method and a wet pulverization method for obtaining a desired particle size of the antibacterial agent carrying these metal ions.
A wet pulverization method in which an antibacterial agent is dispersed in a solvent of a material forming the release layer and then pulverized can be preferably used.

[0015]

According to the present invention, when a thermal transfer recording medium is printed using a thermal head by adding fine particles of an inorganic antibacterial agent having an average particle diameter of not more than twice the film thickness of the release layer to the release layer (2). The added antibacterial agent puts its head on the surface of the transfer paper to develop antibacterial properties.

[0016]

EXAMPLES Specific examples of the present invention will be described.

<Example 1> A polyester film having a thickness of 3.5 μm was prepared by adding 10 parts of inorganic silver-based fine particles having an average particle diameter of 1 μm to carnauba wax as a release layer, and having a thickness of 1 μm.
To a thickness of 3 .mu.m for the colored ink layer, 3 .mu.m of carbon black dispersed epoxy resin, and 0.5% of acrylic resin on the opposite side for the sticking prevention layer.
A thermal transfer recording medium having a thickness of μm was prepared, and an image was printed on paper having antibacterial properties by a serial thermal head mounted on a word processor. As the inorganic antibacterial agent, so-called silver zeolite was used in which 5% of replaceable sodium ions in the zeolite were replaced with silver ions. Further, as the paper having antibacterial property, used was one in which 2% of the silver-substituted zeolite was added to a filling agent and coated.

Example 2 A polyester film having a thickness of 3.5 μm was prepared by adding 10 parts of inorganic silver-based fine particles having an average particle diameter of 1 μm to carnauba wax as a release layer, and having a thickness of 1 μm.
The carbon ink-dispersed epoxy resin is 3 μm as the colored ink layer, the polyamide resin is 2 μm as the adhesive layer, and the acrylic silicone resin is 0.5 μm as the sticking prevention layer on the opposite side. A thermal transfer recording medium was prepared by printing the image on a paper having antibacterial properties with a serial thermal head mounted on a word processor. As the inorganic antibacterial agent, so-called silver zeolite was used in which 5% of replaceable sodium ions in the zeolite were replaced with silver ions. Further, as the paper having antibacterial property, used was one in which 2% of the silver-substituted zeolite was added to a filling agent and coated.

<Comparative Example> Although not shown, the thickness is 3.5 μm.
carnauba wax as a release layer to a thickness of 1 μm on a polyester film of m, a color ink layer of 3 μm of carbon black-dispersed epoxy resin, and a sticking prevention layer of 0.5 μm of acrylic resin on the opposite side. A thermal transfer recording medium was prepared by setting the thickness to 1 and the image was printed on paper having antibacterial properties by a serial thermal head mounted on a word processor. As the paper having antibacterial properties, the above silver-substituted zeolite added with 2% as a filling agent and coated was used.

<Antibacterial Test> An antibacterial test was conducted using the three prints of Examples 1 and 2 and Comparative Example, an antibacterial paper, and a polyethylene film as a control. Sunahachi,
Staphylococcus aureus and Escherichia coli were suspended in distilled water that had been sterilized to 10 ⁵ cells / ml, and 1 ml of this suspension was added dropwise to each sample. After leaving for 24 hours, the bacterial cells were washed out and survived by the pouring method. The number of bacteria was measured. The results are shown in the table below. Escherichia coli Staphylococcus aureus [Example 1] 7.8x10 ¹ 6.3x10 ⁰ [Example 2] 6.2x10 ¹ 4.2x10 ⁰ [Comparative example] 7.8x10 ⁴ 4. 3 × 10 ⁴ [antibacterial paper] 3.4 × 10 ¹ 7.8 × 10 ⁰ [polyethylene] 1.2 × 10 ⁵ 1.0 × 10 ⁵ * Unit: piece / sample

The results of the antibacterial test shown above show that when printing is performed on paper having antibacterial properties with a thermal transfer recording medium having no antibacterial properties, the antibacterial substances are hidden and the antibacterial properties of the antibacterial paper are expressed. Although it is hindered, the print surface can be provided with antibacterial property by using the heat-sensitive transfer recording medium according to the present invention.

[0022]

INDUSTRIAL APPLICABILITY According to the present invention, a thermal transfer recording medium is prepared by adding a fine particle of an inorganic antibacterial agent having an average particle diameter of not more than twice the thickness of the release layer to the thermal head of the thermal transfer recording medium. When printing is performed using the particles, after printing, fine particles appear on the surface of the transferred material, so that characters and images having antibacterial properties can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing a structure of a thermal transfer recording medium according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a configuration of a heat-sensitive transfer recording medium according to another embodiment of the invention, which is shown in cross section.

[Explanation of symbols]

 1 ... Base film 2 ... Release layer containing antibacterial agent 3 ... Colored ink layer 4 ... Sticking prevention layer 5, 7 ... Thermal transfer recording medium 6 ... Adhesive layer

Claims (3)

[Claims] 1. A thermal transfer recording medium having a transfer layer on at least one side of a substrate, which is used in a thermal transfer recording device having a thermal head, and a release layer, a colored ink layer, or a release layer, a colored ink from the substrate. A heat-sensitive transfer recording medium comprising a layer and an adhesive layer, wherein an antibacterial agent is added to the release layer. 2. The heat-sensitive transfer recording medium according to claim 1, wherein the antibacterial agent is an inorganic antibacterial agent having an average particle diameter of not more than twice the thickness of the release layer. 3. The heat-sensitive transfer recording medium according to claim 1, wherein an antibacterial agent containing silver as an antibacterial component is used as the inorganic antibacterial agent.