JPH0528996B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a thermal transfer ribbon, an image forming method using the thermal transfer ribbon, and an information recording card produced by the method. The purpose is to record good gradation image information and highly reliable binary image information.

<Prior Art> Today, cards are widely used in various fields, and their types and uses are wide-ranging. Various information is usually recorded on such cards. One example is magnetic recording on a magnetic recording layer provided on a card, but the majority of information is visual information. As a method for recording visual information, printing is a common method for making multiple copies of the same information. Furthermore, embossing, laser recording, etc. have been conventionally used to record individual information. Furthermore, recently, color images have been recorded using various imaging devices and small computers. A common method for this is thermal sublimation recording using thermal sublimation ink.

Heat-sublimable ink can control the amount of heat-sublimable dye transferred to the recording medium according to the amount of heating, so it can be used not only for binary images such as characters, but also for images with gradation such as photographic images. It also has the feature of being able to record. However, heat-sublimable inks generally have lower thermal sensitivity than heat-melt transfer inks, and have problems such as re-sublimation of heat-sublimable dyes, bleeding, and fading, resulting in poor reliability of recorded images. Ta. The reliability of recorded images is at a level that does not pose a practical problem when used as a general image printer, but high contrast is required for binary images such as gradation images and character recording. This was insufficient for purposes requiring records.

In such cases, it is common practice to record a binary image on the card using heat-melting ink, but since normal heat-melting ink is mainly made of wax, the recording is not durable and is prone to rubbing and friction. It has the disadvantage that records can be easily lost due to damage, etc., which has been a problem for cards. Cards referred to here include prepaid cards, commuter passes, gift certificates, admission tickets, train tickets and other cash vouchers, credit cards, ID cards, student ID cards, etc.
This refers to ID cards, and in any case, there must be no risk of tampering or deterioration of visibility of the character records.

<Problems to be Solved by the Invention> The present invention provides a method for recording a good gradation image and a highly reliable binary image when recording an image consisting of a gradation image and a binary image on cards. The present invention aims to provide a thermal transfer ribbon capable of simultaneously forming images, an image forming method using the thermal transfer ribbon, and an information recording card produced by the method.

<Means for Solving the Problems> The thermal transfer ribbon of the present invention has a structure in which a heat sublimation ink layer and a heat melt transfer ink layer containing a thermoplastic resin as a main component are alternately and repeatedly provided in the length direction of a base material. The image forming method of the present invention uses a thermal transfer ribbon having the above-mentioned configuration, and for images having gradations such as face photographs, a thermal head or a thermal head as a heating means is applied to the heat sublimation ink layer. By applying thermal energy according to the desired image density using a printing plate, heat sublimation ink is transferred and a gradation image is recorded on the card, and 2-tone images such as character images are recorded.
For digital images, binary images are recorded on the same card by transferring highly durable heat-melting transfer ink, which is mainly made of thermoplastic resin, using the same heating means. As a result, an information recording card on which a gradation image and a binary image are transferred and formed is obtained.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is an explanatory diagram showing the image forming method of the present invention, in which an image is recorded on a card-shaped recording medium 10 using a thermal transfer ribbon 30, a thermal head 20, and a pressing platen roller 40.

When performing gradation color recording in the method shown in FIG. 1, first, the yellow portion 31 of the heat sublimable ink layer of the transfer ribbon 30 is superimposed on the card-shaped recording medium 10, and moved in the directions of arrows B and A, respectively. While doing so, yellow transfer recording is performed by the thermal head 20, and after completion of the yellow transfer recording, the recording medium 10 is pulled back in the direction of arrow A' to overlap with the magenta portion 32, and magenta transfer recording is performed in the same manner. Similarly, cyan part 3
After performing the recording in step 3, the heat-melting transfer ink layer 34 is similarly transferred to perform character recording. In this example, character recording is performed after gradation image recording, but this order may be reversed.

FIG. 2 shows an example of recording on a card using the above-described image forming method.

That is, FIG. 2 shows a photographic image 51 of a face formed using thermal sublimation ink and a character image 52 formed using thermal melting transfer ink on a card-shaped recording medium 50, which are recorded by using a thermal head. Recording can be performed on any part of the card, which is a medium. Image data necessary for recording can be input from a commercially available video camera, etc., and character data can also be input from a commercially available personal computer.

Here, the thickness of the recording card is 150 to 300 μm.
Polyester sheets of 500 to 1000 μm, hard PVC sheets or hard PVC/polycarbonate laminated sheets, various paperboards, etc. are generally used. The heat-sublimable dye receiving layer is not particularly limited, and any known material used for general heat-sublimation printers can be used. Furthermore, regarding the size of the area in which the receptive layer is provided, in an information recording card, a photograph of the face is most necessary, and therefore, the area needs to be large enough to match the size of the photograph of the face. Specifically, the short side
A rectangular size with a length of 2.5 to 5 cm and a long side of 2.5 to 6 cm is desirable.

The transfer ribbon is based on a heat-resistant film such as polyester film, polyamide film, cellophane film, or aramid film, or thin paper such as capacitor paper with a thickness of 3 to 50 μm.
A material in which a heat-sublimable ink layer and a heat-melting transfer ink layer are both provided on the base material is used. Here, the heat sublimation ink layer may be one coated with a known heat sublimation ink used in general video printers, etc.
When performing color recording, it is possible to use a material that exhibits the three colors of yellow, magenta, and cyan, which are painted separately, or a material that is coated in four colors by adding a black heat sublimation ink layer. It is also possible to use Of course, if only black recording is performed, a heat sublimable ink layer of one color, black, may be used.

In addition, the heat-melting transfer ink layer is made of a linear saturated polyester resin formed by condensation polymerization of dicarboxylic acid components and diol components, and has a glass transition point of 50°C.
This is a heat-melting transfer ink layer whose main components are a thermoplastic resin made of acrylic resin with a temperature range of 110°C, a colorant, and a lubricant. The above saturated polyester resin has the effect of improving the adhesion of the transfer layer,
The preferred addition amount is 10 to 30% by weight based on the entire thermoplastic resin.The above acrylic resin imparts plasticizer resistance to the overcoat layer, and the glass transition point was determined based on the glass transition point.
This is because chemical resistance and plasticizer resistance are insufficient at temperatures below 50°C, and thermal sensitivity becomes too low at temperatures above 110°C. The coloring agent is not particularly limited as long as it has good visibility; for example, carbon black and various inorganic and organic pigments can be used. The above-mentioned lubricant is required to improve the abrasion resistance of records formed on recording media, and specifically, Teflon powder, polyethylene powder, waxes, metal salts of higher fatty acids such as zinc stearate, etc. are used. I can do it.

The composition ratio of the heat-melting transfer ink layer is as follows:
Thermoplastic resin: 40 to 80% by weight, lubricant: 5 to 30%
% by weight, the colorant is 5 to 30% by weight.

The thermal head serving as the heating means may be of the flatbed type used in ordinary thermal printers, but if the card is particularly thick and difficult to bend, an end-face type thermal head with a heating element provided on the end face of the substrate is more desirable. There are no particular restrictions when using a heat stamp plate.

Heat-melt transfer ink has almost the same thermal sensitivity as heat-sublimation ink, so it does not require a separate heating means for transfer, and can be used with the thermal head or heat stamp used for sublimation transfer recording. It is highly convenient because the board can be used as is.

In addition to cards, the transfer recording medium can also be transparent plastic sheets such as OHP sheets,
Possible examples include flat plastic molded products such as compact disks and floppy disk jackets.

A more detailed explanation will be given below using specific examples.

〔Example〕

<Example 1> Thickness of heat sublimable ink receiving layer provided on recording surface
250μ polyester sheet, edge type thermal head (EUX-E8A4 manufactured by Matsushita Electronic Components Co., Ltd.) and 6μ thick
Polyester film (Lumirror manufactured by Toray Industries, Inc.)
Recording was performed using a transfer ribbon on which a heat-sublimable ink layer and a heat-melting transfer ink layer with a thickness of 3 μm having the following composition were provided.

Carbon black 12 parts by weight methacrylic acid ester (Mitsubishi Rayon BR-
64) 60 parts by weight Vinyl chloride acetate copolymer (VAGH made by UCC) 18 parts by weight Teflon powder 6 parts by weight The end-face type thermal head produces gradation images by modulating the conduction pulse width of the heating element from 2 msec to 20 msec with an applied voltage of 14 V. Recorded. Thereafter, binary image recording was performed with a conduction pulse width of 4 msec. the result,
The thermo-sublimation ink makes it possible to obtain facial photograph images with good gradation, and the heat-melting transfer ink makes it possible to obtain character images with high contrast and strong resistance to rubbing and friction. When a friction test was performed by rubbing the image with a plastic eraser 30 times, no blurring of the letters was observed. After further rubbing 30 times,
Although a slight decrease in density was observed, there was no loss of characters and there was no problem with legibility.

<Example 2> An edge-type thermal head (Mitani Electronics Co., Ltd.) was mounted on a 760μ thick PVC card provided with a heat-sublimable ink receiving layer.
MT-S2-8-1) manufactured by Co., Ltd. and the same transfer ribbon as in Example 1 were used to record facial photographs. The applied voltage is
Gradation images were recorded by modulating the conduction pulse width from 2 msec to 15 msec at 16 V. Thereafter, a character image was recorded with a conduction pulse width of 6 msec. As in Example 1, a rubbing friction test was conducted using a plastic eraser, and no deterioration was observed in the character image area even after 30 reciprocations.

<Effects of the Invention> According to the present invention, a gradation image such as a photograph of a face having good gradation properties is recorded on a transfer recording medium such as a card by heat sublimation ink, and a thermoplastic resin is used as the main component. The present invention has the advantage that it is possible to form a highly robust binary image record using the heat-melting transfer ink using the same device, and it can be used in applications that require recording reliability.

[Brief explanation of the drawing]

The drawings show an example of the method of the present invention, and FIG. 1 is a sketch showing the image forming method of the present invention, and FIG.
The figure is a plan view showing a card on which recording was performed using the image forming method of the present invention. 10, 50... Card-shaped recording medium, 20... Thermal head, 30... Transfer ribbon, 40... Platen roller.

[Claims]

1. A thermal transfer sheet comprising an ink layer in which a heat sublimable dye and a binder are mixed on a substrate, wherein the binder is composed of a mixed composition of 15 parts by weight or more of an epoxy resin and a butyral resin. Thermal transfer sheet.

Claims (1)

A transfer process in which heat-melting transfer ink layers consisting mainly of a thermoplastic resin made of acrylic resin with a lath transition temperature in the range of 50°C to 110°C, a coloring agent, and a lubricant are alternately and repeatedly provided in the length direction of the ribbon. A ribbon is used to form two types of images on a recording medium using a thermal head or a heat printing plate as a heating means: a gradation image using heat sublimation ink and a binary image using heat melt transfer ink. Image forming method. 5 It is recommended to use a transfer ribbon in which the heat-sublimable ink layer is sequentially painted in the length direction of the ribbon with heat-sublimable ink of three colors: yellow, magenta, and cyan, or four colors of heat-sublimable ink including ink. The image forming method according to claim 4. 6. The image forming method according to claim 4, wherein the colorant of the heat-melting transfer ink layer is a pigment, or a pigment and a heat-sublimable dye. 7. In an information recording card that records an image by transferring transfer ink from a thermal transfer ribbon onto the surface using a thermal head or a heat printing plate as a heating means, a method for receiving thermal sublimation ink provided over a specific area of the surface. A gradation image is recorded on the layer using heat sublimation transfer ink, and a linear saturated polyester resin formed by condensation polymerization of a dicarboxylic acid component and a diol component and a glass transition point of 50°C to 110°C are applied to any area of the surface. 1. An information recording card characterized in that a binary image is recorded using a heat-melting transfer ink whose main components are a thermoplastic resin such as an acrylic resin having a temperature range of 0.degree. C., a colorant, and a lubricant. 8. The information according to claim 7, characterized in that the gradation image is a full-color image using thermal sublimation ink of three colors yellow, magenta, and cyan, or four colors including black ink in the length direction. record card. 9. The information recording card according to claim 7, wherein the area of the heat-sublimable ink receiving layer is rectangular with a short side of 2.5 to 5 cm and a long side of 2.5 to 6 cm.