JPH05169695A - Thermal printer - Google Patents

Abstract

PURPOSE:To form an image on printing paper of any type or perform printing on plain paper by a method wherein a sublimable dye layer and an image receiving layer are provided on an ink sheet, and a sublimable dye is also transferred while the image receiving layer is transferred onto plain paper. CONSTITUTION:An ink sheet 3 is composed of a sheet base layer 5, a sublimable dye layer 6, a release layer 8, a melting image-receiving layer 7, and an adhesive layer 9. Printing paper 4 is general-purpose plain paper. A sublimable dye sublimated by heat can be transferred to the melting image-receiving layer 7 similarly to a coating material for specialty paper, and the image-receiving layer 7 is thermally transferred per se. A thermal energy generated by a heating element 1a of a thermal head 1 reaches the sublimable dye layer 6 through the base layer 5 of the sheet 3, furthermore reaching the melting image-receiving layer 7 and the adhesive layer 9 through the release layer 8. A transfer initiation temperature T1. of the image-receiving layer 7 is different from a transfer initiation temperature T2 of the dye layer. By using this difference in characteristics, the image-receiving layer 7 and the dye layer 6 can be separately transferred.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink sheet for a thermal printing apparatus of the type which forms an image on a sheet by utilizing heat generated by a heating element, and a transfer method thereof.

[0002]

2. Description of the Related Art In the field of office equipment and the like, a printing apparatus utilizing heat is widely used. Typical printing methods of these printers will be briefly described with reference to FIG.

An ink sheet 3 is arranged on a heating element 1a of the thermal head 1, and a printing paper 11 is arranged below the ink sheet 3. The heat generated from the heating element 1a passes through the sheet base layer 5 of the ink sheet 3 and reaches the sublimation dye layer 6. By this heat energy, the sublimation dyes 6Y and 6M of the sublimation dye layer 6 are sublimated and only the dye is transferred 11Y to the photographic printing paper 11.

The photographic printing paper 11 is a special paper which is composed of a front coat layer 11a, an image receiving layer 11b, a base layer 11c and a back coat layer 11d.

To form a color image, yellow,
Images of three or four colors of magenta, cyan, or black are superposed and formed. Therefore, the above-mentioned yellow 6Y, magenta 5M, cyan (not shown) or black sublimation dyes are arranged on the ink sheet 3 in a face-sequential manner, and the respective colors are sequentially superposed and transferred onto the photographic paper. The image was formed. For this reason, pressure is applied between the ink sheet 3 and the printing paper 11 by the thermal head 1 and the platen roller 2 in order to enhance the adhesion and improve the transfer characteristics.

[0006]

As described above, in the conventional printer device, in order to sublimate and superimpose the dye, the special paper with the special coating on the surface is required, and the running cost at the time of printing is reduced. In a high example, even if plain paper is used, the sublimation dye is not transferred and an image cannot be formed. Therefore, there was a problem that special paper was always required.

[0007]

In order to solve the above problems, the present invention provides an image by forming a sublimation dye layer and an image receiving layer on an ink sheet, and transferring the sublimation dye onto the plain paper while transferring the image receiving layer. Is a thermal printer that forms a. Therefore, the sublimation temperature is set higher than the transfer temperature.

[0008]

Embodiments of the present invention will be described in detail below with reference to FIGS. 1, 2, 3, and 4. 1, 2 and 3
FIG. 3 is a detailed view showing a print portion of the thermal printer according to the present invention. FIG. 4 is a graph showing the thermal characteristics of the ink sheet.

In FIG. 1, 1 is a thermal head and 2 is a platen roller. The ink sheet 3 and the printing paper 4 are arranged between the thermal head 1 and the platen roller 2. Ink sheet 3 and photographic paper 4
Although the feeding method and the feeding method are not shown, printing is performed while feeding the ink sheet 3 and the printing paper 4 in the arrow X direction. After printing one screen, thermal head 1
The pressure applied between the platen roller 2 and the platen roller 2 is released, and the printing paper 4 is returned to the printing start position. (Arrow Y direction) At this time, the ink sheet 3 is also fed in the arrow Z direction in order to find the next color to be printed.

The ink sheet 3 is composed of a sheet base layer 5, a sublimation dye layer 6, a peeling layer 8, a melt image receiving layer 7 and an adhesive layer 9, and the printing paper 4 is a commonly used plain paper. is there. Like the conventional coating material for special paper, the heat-fusible image-receiving layer 7 can transfer a sublimation dye sublimated by heat, and the image-receiving layer 7 itself is also thermally transferred.

The thermal energy emitted from the heating element 1a of the thermal head 1 passes through the sheet base layer 5 of the ink sheet 3 and reaches the sublimation dye layer 6. Furthermore, this thermal energy passes through the peeling layer 8 and reaches the melted image receiving layer 7 and the adhesive layer 9. FIG. 4 shows the relationship between the transfer rate and the temperatures of the fused image-receiving layer 7 and the sublimation dye layer 6 at this time. There is a difference between the transfer start temperature T1 of the melted image receiving layer 7 and the transfer start temperature T2 of the sublimation dye layer. The sublimation dye layer transfer start temperature T2 is a temperature near the melting image receiving layer transfer rate of 100% at the same time. By utilizing the difference between these two characteristics, it is possible to separately transfer the melt image receiving layer 7 and the sublimation dye layer 6. If the image is transferred at a temperature T3 higher than the temperature T2, the melted image receiving layer 7 is transferred 100%, but the sublimation dye layer 6 is transferred by A% to a required density.

In the case of FIG. 1, heat energy is selectively applied only to the dot portions to be formed according to the image information, and the dye of the sublimation dye layer 6 is transferred to the melt image receiving layer 7 and at the same time the melt image receiving layer 7 and the adhesive layer. 9 is a method of transferring 9 to the printing paper 4.

Since the melted image receiving layer 7 and the adhesive layer 9 are colorless and transparent, there is no problem in color reproducibility even when a plurality of colors are overprinted.

In the system shown in FIGS. 2 and 3, the thermal head 1 and the platen roller 2 have the same configurations as those shown in FIG. In the constitution of the ink sheet 3, as shown in FIG. 2, only the ink sheet on which the yellow dye layer 6Y is arranged, the peeling layer 8, the melt image receiving layer 7, and the adhesive layer 9 are formed.
have. As shown in FIG. 3, the ink sheet portion on which the magenta dye layer 6M and the cyan dye layer 6C are arranged is composed of only the sheet base layer 5 and the sublimation dye layer 6.

In order to obtain a color image, three colors of yellow, magenta and cyan or black are overlaid and expressed. At this time, at the time of transferring the yellow dye layer 6Y which is the first image to be printed, the melted image receiving layer 7 is transferred 10Y to the printing paper 4 at the same time, and at the time of transferring the magenta dye and the cyan dye, it is performed on the melted image receiving layer 7 previously transferred (10M ) Is configured as.

[0016]

The present invention has the following effects by having the above-mentioned structure. Since the image receiving layer as well as the sublimation dye is transferred by the melting method, the type of printing paper on which an image is formed is not selected, and thus printing on plain paper is possible. This makes it possible to obtain a high-quality color image with low running cost during printing.

[Brief description of drawings]

FIG. 1 is a detailed view of an image forming portion of a thermal printer in which a fused image receiving layer according to an embodiment of the present invention is arranged on the entire surface of an ink sheet.

FIG. 2 is a detailed view of a portion in which a melt image-receiving layer according to an embodiment of the present invention is arranged only in a yellow sublimation dye portion and the yellow dye and the melt image-receiving layer are transferred.

FIG. 3 is a detailed view of the same magenta dye transfer.

FIG. 4 is a graph showing temperature and transfer rate of the ink sheet according to the present invention.

FIG. 5 Example

[Explanation of symbols]

 1 Thermal Head 1a Heating Element 2 Platen Roller 3 Ink Sheet 4 Printing Paper 5 Sheet Base Layer 6 Sublimation Dye 6Y Yellow Sublimation Dye Layer 6M Magenta Sublimation Dye Layer 6C Cyan Sublimation Dye Layer 7 Melt Image Receiving Layer 8 Release Layer 9 Adhesive Layer 10 Transfer Image 10Y Yellow transfer image 10M Magenta transfer image 11 Dedicated image receiving paper 11a Surface coating layer 11b Image receiving layer 11c Base layer 11d Backside coating layer 11Y Transfer dye Arrow X printing direction Arrow Y Paper returning direction Arrow Z Ink sheet feeding direction T1 Melting image receiving layer transfer start temperature T2 Sublimation dye transfer start temperature

Claims (2)

[Claims] 1. Sublimation dyes of a plurality of colors, a fused image-receiving layer that receives an image when the sublimation dyes are sublimated, and is transferred by application of heat energy on the base layer, and the image-receiving surface of the image-receiving layer. An ink ribbon having an adhesive layer applied to the opposite side and having an adhesive layer that is viscous when heat energy is applied, a thermal head for selectively applying heat energy from the base layer side of the ink ribbon, and the ink ribbon A thermal printer comprising: a platen that holds paper together with the thermal head. 2. The thermal head according to claim 1, wherein the sublimation temperature of the sublimation dye is set to a high temperature with respect to the transfer temperature of the melted image receiving layer of the ink ribbon.