JP2537707B2 - Thermal transfer medium and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer medium used in a thermal transfer system, and in particular, ticket papers such as boarding tickets, commuter tickets, pass tickets, prepaid cards, ID cards,
The present invention relates to a heat transfer medium suitable for cards such as safety cards and labels such as POS labels, and a method for manufacturing the same.

[0002]

2. Description of the Related Art With the rapid development of OA and FA, various terminals are required, and in particular, there is a remarkable demand for recording devices such as facsimiles and printers for converting electric signals into visible images. The thermal transfer recording method is widely used for these terminals because the apparatus has advantages of being simple and compact, noiseless, and maintenance-free. Recently, the thermal transfer recording method is used in combination with a magnetic recording method to increase demand for ticket papers such as tickets, commuter passes, pass tickets, cards such as prepaid cards, ID cards, and safety cards, as well as physical distribution and distribution. It has come to be used for labels such as POS labels that are used. These ticket papers,
In order to obtain reliability and security, cards and labels have strict requirements, that is, image receptivity for obtaining transferred images of high quality and high resolution, water resistance, sweat resistance, oil resistance,
It is necessary to satisfy chemical resistance such as alcohol resistance, acid resistance, alkali resistance, and plasticizer resistance. Also, in the case of paper sheets and cards combined with the magnetic recording method, it is necessary to accurately read the bar code printed on the labels, because it passes through a device containing a magnetic head for reading the magnetic recording information at high speed. Wear resistance is also required due to its properties.

Further, in these heat-transferable media, it is necessary to print patterns, marks, characters, etc., so-called tint block printing on fare tickets, commuter tickets, pass tickets, etc. to prevent tampering. In addition, it is necessary to print frames, characters, etc. in addition to the transferred images in advance on the labels, etc. Furthermore, color printing and character printing should be performed in advance on cards such as ID cards and prepaid cards that also serve as advertising media. You may need to leave it. These prints are under the ink receiving layer (between the support and the ink receiving layer)
However, in consideration of the purpose of tint block printing, the manufacturing cost, and the support for small-lot production of a wide variety of products, it is necessary to provide it on the ink image receiving layer. Therefore, the ink image receptivity, chemical resistance, and abrasion resistance of the printed image portion itself become a problem.

In the conventional thermal transfer recording system, waxes such as paraffin wax and microcrystalline wax are mainly used on a support such as an extremely thin polyethylene terephthalate film, and higher fatty acids such as stearic acid and higher alcohols such as stearyl alcohol and dyes. , A thermal transfer ink layer composed of a coloring material composed of pigment, and a heat resistant protective layer composed of silicone resin, nitrocellulose, etc. on the opposite surface to prevent sticking with the thermal head The medium (ink ribbon) is overlaid on the heat transfer medium, and the heat-sensitive protective layer is heated by the thermal head according to the recording information, and the information image of the heat transfer medium is thermally transferred onto the heat transfer medium to obtain the desired image. Was formed. In this case, since the conventional thermal transfer medium is paper, polyethylene terephthalate film or polyethylene laminated paper having no ink receptivity, the thermal transfer ink has a composition mainly composed of a soft wax in order to maintain the ink receptivity. It was However, when the heat-sensitive transfer ink mainly composed of the wax is transferred onto the heat-transferred medium, the abrasion resistance and the chemical resistance cannot be satisfied, and the transferred image has a drawback that it can be immediately removed by a nail or the like. Was. To remedy this drawback, carnauba wax, polyethylene wax,
There has been proposed a thermal transfer ink mainly composed of wax having a low penetration such as montan wax or a thermoplastic resin such as a polyester resin, an epoxy resin, an ethylene vinyl acetate copolymer resin and a polyamide resin. In particular, the heat-sensitive transfer ink mainly composed of the thermoplastic resin is effective in chemical resistance and abrasion resistance, and therefore has been rapidly developed recently.

However, even though these thermal transfer inks have been improved, the conventional thermal transfer medium has problems in image receiving property, abrasion resistance (fixing property), etc. of the thermal transfer ink, and is therefore practically sufficient. These characteristics cannot be satisfied. On the other hand, since the material of the printing ink of the print processing layer provided on the ink image receiving layer is poor in matching with the thermal transfer ink, such as conventionally using an ultraviolet curing acrylic resin, the transfer ink image on the printed portion is unclear, However, there is a problem in that the chemical resistance is low, and the abrasion resistance of the printed portion and the ink image thermally transferred onto the printed portion is poor. Further, there is a problem that there is a large difference in ink image receptivity between the ink image receiving layer and the print processing layer, and a difference in chemical resistance and abrasion resistance of the transferred image. For these reasons, the ink image-receiving layer and the print processing layer that constitute the conventional heat-transferred medium do not eventually satisfy all of the image-receiving property and the chemical resistance and abrasion resistance of the heat-sensitive transfer ink.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a heat-sensitive transfer ribbon having an ink image-receiving layer which constitutes a heat-transferred medium such as a ticket, a card and a label used in a thermal transfer system and a print processing layer provided on the ink image-receiving layer. It is intended to improve the image receptivity to ink and to improve chemical resistance such as sweat resistance, oil resistance, alcohol resistance, acid resistance, alkali resistance, and plasticizer resistance, and abrasion resistance.

[0007]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors have successively laminated an ink image-receiving layer for receiving a thermal transfer ink and a print treatment layer on a support. In order to complete the present invention, the ink used in the print treatment layer contains at least one of a polyester resin and an epoxy resin, and the print treatment layer is formed by using a gravure printing method. I arrived.

Next, the constituent materials and manufacturing method of the thermal transfer medium of the present invention will be described in detail below. The ink image-receiving layer constituting the heat-transferable medium of the present invention contains at least one kind of polyester resin or epoxy resin and a lubricant.
Examples of the polyester resin used in the ink image-receiving layer of the present invention include aliphatic polyester, polydimethylene malonate, polyethylene terephthalate, polytrimethylene terephthalate, polydiethylene glycol terephthalate, polyethylene isophthalate, polyethylene phthalate, polyethylene-1,5-. Naphthalate,
Polyethylene-1,4-naphthalate, polyethylene-
2,7-naphthalate, polyester (diethylene glycol-diphenylcarboxylic acid), polyester (bis-P-carboxyphenoxybutane-ethylene glycol) and the like can be mentioned, and they can be used alone or in combination of two or more. In the present invention, it is preferable to use a polyester resin having a glass transition temperature (hereinafter referred to as Tg) of 60 ° C. or higher as the polyester resin. That is, when Tg is higher than 60 ° C., chemical resistance and abrasion resistance can be further improved.

Examples of the epoxy resin used in the ink image-receiving layer of the present invention include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin, alicyclic epoxy resin, and phenol. Examples thereof include novolac type epoxy resin, cresol novolac type epoxy resin, and glycidyl ether type epoxy resin, which may be used alone or in combination of two or more kinds. In the present invention, it is preferable to use the epoxy resin having a softening point of 100 ° C. or higher. That is, the softening point is 100 ° C
When it is higher, more sufficient properties in chemical resistance and abrasion resistance can be obtained. The Tg and the softening point were all measured by the DSC method (heating rate 10 ° C / min, peak value in analysis).
Is required in.

As the lubricant to be blended in the ink image-receiving layer, carnauba wax, candelilla wax, polyethylene wax, polypropylene wax, ester wax, montan wax, montan wax derivative, oxidized microwax, Fischer-Trovsch wax, hardened castor oil. Waxes such as palmitic acid,
Higher fatty acids such as myristic acid, stearic acid and oleic acid, fatty acid amides such as palmitic acid amide, stearic acid amide and oleic acid amide, lauryl palmitate,
Stearyl stearate, stearyl behenate, esters of higher fatty acids such as behenyl behenate, stearyl alcohol, higher alcohols such as behenyl alcohol, zinc stearate, barium stearate, fatty acid metal salts such as calcium stearate, fine particles of fluorocarbon,
Etc. can be mentioned. Among these lubricants, polyethylene wax is particularly preferable in the present invention. The amount of the above-mentioned lubricant compounded is 0.5 to 30 parts by weight, preferably 3 to 15 parts by weight, based on 100 parts by weight of the total solid content in the ink image-receiving layer. If the blending amount is less than 0.5 part by weight, the friction coefficient of the ink image-receiving layer tends to be large and the abrasion resistance tends to be lowered. On the contrary, when the amount is more than 30 parts by weight, the image-receiving property and the fixing property of the heat-sensitive transfer ink tend to decrease.

The ink image-receiving layer of the present invention contains an appropriate amount of an inorganic or organic pigment, an antioxidant, a colorant, an antistatic agent, a curing agent, etc. in addition to the above-mentioned thermoplastic resin and lubricant, and is suitable. 0.01 to 20 μm, preferably 0.1 to 20 μm, preferably 0.1 to 20 μm on the support by a solvent coating method, various coating methods such as gravure printing and screen printing, and a printing method using a coating material obtained by dissolving or dispersing in a solvent. 10μ
It is provided to have a thickness of m.

The print treatment layer of the present invention is provided by using a printing ink having a composition containing at least one of a polyester resin and an epoxy resin. As the polyester resin used in the print treatment layer, since the print treatment layer needs to have ink image receptivity to a thermal transfer ink, chemical resistance and abrasion resistance similar to those of the ink image receptive layer, the same polyester as the ink image receptive layer is required. Resin is applied. Similarly, the epoxy resin used for the ink image receiving layer is applied as the epoxy resin. The print treatment layer of the present invention is obtained by adding a lubricant, a pigment, an antistatic agent, a coloring agent, a curing agent, etc., if necessary, in addition to the above thermoplastic resin, and dissolving or dispersing them in a suitable solvent. The printing ink is used to form a print on the ink image-receiving layer by gravure printing.

The gravure printing method used in the present invention is
Ink is supplied to a metallic gravure plate roll with fine halftone dot-shaped recesses in the printed image area to remove unnecessary ink with a blade, and then the ink remaining in the recesses is transferred to the substrate and printed. The gravure printing method is most suitable for printing using a solvent-based ink that satisfies the required properties such as ink image receptivity, chemical resistance, and abrasion resistance. In printing methods other than the gravure printing method, for example, in the screen printing method, since the amount of ink is large, the transferred image from the heat-sensitive transfer ribbon is bad due to the unevenness, and in the flexographic printing method, the rubber roll is attacked by the solvent and is uniform for a long time. Printing is not possible, and the offset printing method is not practical because of problems such as plate material and drying material.

The support used in the present invention includes polyethylene terephthalate, polyimide, polycarbonate,
Resin films such as cellophane, aromatic polyamide, polyolefin and vinyl chloride, high quality paper, coated paper, art paper, woven sheet, laminated paper, synthetic paper, metal plate, glass and the like can be used.

The surface of the heat-transferable medium of the present invention is desired to have good smoothness in order to improve the adhesion to the heat-sensitive transfer ink ribbon. That is, the Beck smoothness (JIS 8119-1976) of the ink image-receiving layer provided with the print processing layer is preferably 300 seconds or more, more preferably 500 seconds or more. In order to obtain such a value as the smoothness of the ink image receiving layer provided with the print processing layer, a support made of a resin film having high smoothness is used as the support, or an anchor coat layer is provided on the support. This can be achieved by providing a surface treatment such as calendering after providing the ink image-receiving layer or after providing the print processing layer.

The structure (layer structure) of the thermal transfer medium of the present invention will be described with reference to the drawings. FIG. 1 shows the basic structure of the heat transfer medium of the present invention. 2 to 4 are schematic cross-sectional views showing another embodiment of the heat transfer medium of the present invention, the present invention is not limited to these configurations. FIG. 1 shows a thermal transfer medium in which an ink image receiving layer 2 and a print processing layer 3 are provided on a support 1, and FIG. 2 shows an ink image receiving layer 2 and a print processing layer 3 are provided on a support 1 and vice versa. This is a thermal transfer medium in which an adhesive layer 4 and a release paper 5 are sequentially provided on the surface, and FIG. FIG. 4 shows a thermal transfer medium in which a layer 7 is sequentially provided. Further, FIG. 4 shows an ink image receiving layer 2 and a print treatment layer 3 provided on a support 1, and a magnetic recording layer 6, a hiding layer 8 and a second printing layer on the opposite surface. This is a thermal transfer medium in which a layer 9 and a protective layer 7 are sequentially provided.

The magnetic recording layer 6 contains a ferromagnetic powder such as γ-Fe ₂ O ₃ and barium ferrite in a binder such as polyester resin, vinyl chloride resin, polyurethane resin and vinyl chloride / vinyl acetate copolymer. If necessary, a pigment or the like is uniformly dispersed, and provided by a solvent coating method, gravure printing, or the like so as to have a thickness of 1 to 30 μm, preferably 3 to 15 μm on the support opposite to the ink image receiving layer. .

For the purpose of preventing forgery, a high magnetic permeability magnetic recording layer of sendust, permalloy or the like, and a magnetic recording layer of low coercive force of about 200 to 1000 oersted such as iron oxide magnetic powder are laminated by the above method. You can also do it. If necessary, a second printing layer 9 such as a company name, notes, commercials and various marks and patterns can be provided on the magnetic recording layer by printing such as gravure printing and flexographic printing. Here, in order to obtain a good second printed layer, it is better to provide a hiding layer 8 between the magnetic recording layer 6 and the second printed layer 9 in order to hide the coloring of the magnetic recording layer. The concealing layer can be formed by coating or printing a coating material in which a pigment such as aluminum paste or titanium oxide is uniformly dispersed in a resin such as polyester resin or polyurethane resin.

A protective layer 7 may be provided on the magnetic recording layer (or the second printed layer when the second printed layer 9 is set) for the purpose of protecting the surface of the magnetic recording layer 6. Examples of the binder for the protective layer include polyester resins, polyurethane resins, polystyrene resins, various fiber-based resins, polyimide resins, silicone resins, fluororesins, polyarylate resins, polycarbonate resins, phenol resins, epoxy resins, alkyd resins, and melamine. Examples include various thermoplastic resins and thermosetting resins such as resins and copolymers between these resins. The protective layer may be prepared by adding wax, silicone, pigment, etc. to the binder, kneading, or dissolving or dispersing in an appropriate solvent to obtain an ink or paint, which is solvent coating, gravure printing, flexo printing, screen. 0.01 to 10 on the magnetic recording layer (or the second printing layer when the second printing layer is set) by printing, offset printing, or the like.
It is provided to have a thickness of μm, preferably 0.1 to 5 μm.

[0020]

EXAMPLES The present invention will be specifically described below with reference to examples, but these examples do not limit the present invention. In addition, all compounding parts mean parts by weight. Example 1 Glass beads were added to the above mixture and dispersed for 2 hours with an attritor, and then 250 μm thick polypropylene synthetic resin (Oji Yuka Synthetic Paper Co., Ltd .: YUPO base paper FP250).
An ink image-receiving layer was formed by coating the above-mentioned support by a solvent coating method so that the coating amount after drying was 2.0 μm. Glass beads were added to the above mixed solution and dispersed for 2 hours with an attritor to prepare an ink for a print processing layer. Next, a print treatment layer was formed on the ink image-receiving layer by a gravure printing method using the ink to obtain a heat transfer medium of the present invention. As the gravure printing plate, a plate having a plate depth of 25 μm and a number of lines of 175 and a mesh pattern was used.

Example 2 After dispersing the above mixed solution in a ball mill for 8 hours, Add the above curing agent and disperse for an additional 1 hour, then add a thickness of 188
It is applied by a solvent coating method on a support made of a milky-white polyethylene terephthalate film having a thickness of μm, and while the coating material is in an undried state, an orientation treatment is performed by a magnetic field orientation treatment device, and the coating is dried at 100 ° C. for 5 minutes to have a thickness of 15
A μm magnetic recording layer was formed. The above-mentioned mixed solution was stirred with a disper to dissolve the binder, and then was coated on the above-mentioned magnetic recording layer by a solvent coating method so that the coating thickness after drying was 3.0 μm to form a protective layer. . Glass beads were added to the above mixed solution and dispersed by an attritor for 2 hours, and then the surface of the support opposite to the laminated side was coated by a solvent coating method so that the coating thickness after drying was 2.0 μm. Then, an ink image receiving layer was provided.

[0022] Glass beads were added to the above mixed solution and dispersed for 2 hours with an attritor to prepare an ink for a print treatment layer, and the ink was used to form a print treatment layer on the ink image receiving layer by a gravure printing method. A heat transfer medium of the present invention was obtained. As the gravure printing plate, a plate having a plate depth of 25 μm and a number of lines of 175 and a mesh pattern was used.

Example 3 A thermal transfer medium of the present invention was obtained in the same manner as in Example 2 except that the formulation of the ink for the print processing layer was changed as follows.

Example 4 A thermal transfer medium of the present invention was obtained in the same manner as in Example 2 except that the formulation of the ink for the print processing layer was changed as follows.

Comparative Example 1 A thermal transfer medium for comparison was obtained in the same manner as in Example 2 except that the formulation of the ink for the print processing layer was changed as follows.

Comparative Example 2 A heat transfer transfer medium for comparison was obtained in the same manner as in Example 2 except that the formulation of the ink for the print processing layer was changed as follows.

Next, the method for producing the heat-sensitive transfer ink ribbon used for evaluating the heat-sensitive transfer medium of Examples and Comparative Examples will be described below. The excellent characteristics of the heat-sensitive transfer medium of the present invention are the heat-sensitive transfer ink ribbons. It is not limited by
First, a heat-resistant layer made of silicon resin having a thickness of 0.5 μm was set on a polyethylene terephthalate film having a thickness of 4.5 μm. Next, a thermal transfer ink obtained by dispersing the following mixed solution with an attritor for 2 hours was applied on the surface opposite to the heat-resistant layer by a solvent coating method to give a coating amount of 3 μm.
The thermal transfer ink ribbon used in the present invention was obtained by setting so as to be m.

Using the above heat-sensitive transfer ink ribbon, the surface smoothness, sweat resistance, oil resistance, alcohol resistance, acid resistance, alkali resistance of the heat transfer mediums of Examples and Comparative Examples were measured.
Table 1 shows the results of evaluation of various properties such as chemical resistance, which is plasticizer resistance, abrasion resistance, and transferability. Moreover, the measuring method and the evaluation method of each of the various characteristics are shown below. In addition,
"Ink image receptivity" with respect to the thermal transfer ink is shown as a result of comprehensive evaluation of various properties in Table 1. (A) Surface smoothness Beck smoothness (JIS. 8119-1976) (b) Transferability High-density thermal printer (printer equipped with a thermal head of 8 dots / mm: printing energy;
65 mJ / dot, pulse width; 1.5 ms) and the above ink ribbon were used to perform transfer, and image density unevenness, uniformity, sharpness, and the presence or absence of random bridges and voids were evaluated. All evaluations are visual evaluations using enlarged photographs and the like. ○: All evaluation items are satisfied. B: Only one evaluation item has a defect. X: The evaluation item has two or more defects. (C) Alcohol resistance The thermal transfer medium transferred by the printer of (b) was immersed in ethanol for 2 minutes, and the change of the transfer surface was examined. ○: Transfer surface (transfer image area, ink image receiving layer, print processing layer)
There is almost no peeling, scratches, fading or erasing. Δ: Transfer surface (transfer image area, ink image receiving layer, print processing layer)
Some peeling, scratches, discoloration, and fading are seen. X: Transfer surface (transfer image area, ink image receiving layer, print processing layer)
Peeling, scratches, fading, and erasing are quite visible. (D) Acid resistance 5% acetic acid aqueous solution of pH 3 is used. The evaluation method complies with (c). (E) Alkali resistance pH 12, 1N sodium hydroxide aqueous solution is used. The evaluation method complies with (c). (F) Gasoline resistance Use gasoline. The evaluation method complies with (c). (G) Oil resistance After transferring with the printer of (b), a few drops of edible soybean oil was dropped on the transfer surface, and after 24 hours, the oil was wiped off with gauze to examine the change of the transfer surface. The evaluation method complies with (c). (H) Plasticizer resistance After transferring with a printer of (b), a plasticizer-containing plastic eraser was pressure-bonded to the transfer surface at a pressure of ² kg / cm ² , left for 24 hours, and then the plastic eraser was peeled off. The change of the transfer surface was examined. ○: No change at all Δ: Transfer surface to eraser (transfer image area, ink image receiving layer,
Printed layer) transfer, peeling, stains, etc. X: Transfer surface to eraser (transfer image area, ink image receiving area,
Transfer, peeling, and dirt of the print processing layer) are considerably seen. (I) Abrasion resistance After transfer with the printer of (b), a paperboard abrasion tester (manufactured by Kumagai Riki Kogyo Co., Ltd.) was used and a polishing sheet (manufactured by Sankyo Rikagaku Co., Ltd., product name Lapping Sheet WA # 8000) was used. Abrasion resistance of the transfer surface against room temperature: 20 ° C., load: 500
g / cm, rubbing frequency: 1000 reciprocations were examined under constant conditions. ○: Transfer surface (transfer image area, ink image receiving layer, print processing layer)
Almost no scratches, peeling, or dirt are seen. Δ: Transfer surface (transfer image area, ink image receiving layer, print processing layer)
Some scratches, peelings, and stains can be seen. X: Transfer surface (transfer image area, ink image receiving layer, print processing layer)
There are at least two scratches, peelings, and stains, or even one is large. (J) Sweat resistance After immersion for 1 week in the artificial sweat solution (acidic and alkaline) specified in JIS L 0848-1978, the test of (h) is performed.

[0029]

[Table 1]

As is clear from Table 1, the heat-transferable medium of the present invention has a structure in which an ink image-receiving layer for receiving a heat-sensitive transfer ink and a print processing layer are sequentially laminated, and the ink image-receiving layer and the print processing layer are formed. Since it contains at least one type of polyester resin or epoxy resin, it has various chemical resistance such as sweat resistance, oil resistance, alcohol resistance, acid resistance, alkali resistance, plasticizer resistance, abrasion resistance, etc. The characteristics were satisfied, and excellent thermal transfer energy sensitivity and transfer quality could be obtained.

EFFECTS OF THE INVENTION Since the heat transferable medium of the present invention has chemical resistance such as sweat resistance, oil resistance, plasticity resistance and abrasion resistance, and excellent ink image receptivity, it can be used for tickets, commuter passes, I got a pass. Therefore, the transfer medium of the present invention can be suitably used for ticket papers such as boarding tickets, commuter tickets, pass tickets, cards such as prepaid cards, ID cards, safety cards, and labels such as POS labels.

[Brief description of drawings]

[Figure 1]

FIG. 4 is a cross-sectional view showing a structural example of a thermal transfer medium of the present invention.

[Explanation of symbols]

 1 Support 2 Ink Image Receiving Layer 3 Print Processing Layer 4 Adhesive Layer 5 Release Paper 6 Magnetic Recording Layer 7 Protective Layer 8 Shielding Layer 9 Second Printing Layer

Continuation of the front page (56) Reference JP-A 63-95988 (JP, A) JP-A 1-215588 (JP, A) JP-A 1-238987 (JP, A) JP-A 62-25089 (JP , A) JP-A-64-47585 (JP, A)

Claims (2)

(57) [Claims] 1. A thermal transfer medium in which an ink image-receiving layer for receiving a thermal transfer ink and a print treatment layer are sequentially laminated on a support, wherein the ink image-receiving layer and the print treatment layer are at least one of a polyester resin or an epoxy resin. A thermal transfer medium containing a seed. 2. When providing a print-treated layer of a heat-transferable medium in which an ink image-receiving layer for receiving a heat-sensitive transfer ink and a print-treated layer are sequentially laminated on a support, at least one of a polyester resin and an epoxy resin is used. A method for producing a thermal transfer medium, which comprises printing the contained ink by a gravure printing method.