JPH0337518B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a transfer type thermal recording device, which is expected to be applied to color printers and the like.

Transfer-type thermal recording is a recording method in which a thin solid ink coated on an ink ribbon (thermal transfer sheet) is heated and softened using a heating resistor, and the ink is transferred and recorded onto plain paper or the like. The recording speed is not very fast, but the recording noise is low and it can be printed on plain paper. Other features include a simple mechanism, easy maintenance, color printing, and long shelf life of prints. For this reason, the transfer type thermal recording method is seen as the favorite recording method for simple color printers, which are in strong demand in the market (Nikkei Electronics No. 287
(1982.3.29) P72).

Figures 1 to 4 are explanatory diagrams showing the principle of the transfer-type thermal color printer known so far (Nikkei Electronics No. 276
(1981.10.26) P156, No. 287 (1982.3.29) P71/72). FIG. 1 shows an example in which three types of tape-like films are used. The thermal head 11 has three heating elements arranged in a vertical row. Yellow, magenta, and cyan cassette-shaped ink films (thermal transfer sheets) Y1, M1, and C1, respectively.
to scan horizontally. The recording paper 2 is fed in a direction perpendicular to the scanning direction of the thermal head, as indicated by the arrow. However, this method has the disadvantage that the horizontal axis of the device becomes long. In the conventional example shown in FIG. 2, a tape-shaped ink film 42 is colored yellow Y2, magenta M2, and cyan C2 at fixed lengths (three-color series type). The ink film 42 is used by being wound around the open reels 31 and 32. The thermal head 12 has heating elements arranged in a vertical line, and prints by scanning them in the horizontal direction, which is a so-called line-sequential recording method. The ink film 42 is scanned from the right reel 31 to the left reel 32, and the thermal head 12 is scanned from the left to the right. The first print is yellow, then magenta, and finally cyan. Thermal head 12
is returned to its initial position on the left each time. This method has a simple mechanism because the ink film 42 and the recording paper 2 need only be fed in one direction, but the reels 31 and 32 for winding the ink film 1 are large, and the ink film 1 cannot be wound easily. There are problems such as high speed is required for this process, which causes problems in positioning accuracy. Fig. 3 shows a system in which the tape-shaped ink film 43 of three colors (yellow Y3, magenta M3, cyan C3) is arranged in parallel in the method shown in Fig. 1, so that only one thermal head 13 is required. . In this case, it is necessary to raise and lower the film for each line of printing, which has the disadvantage that the mechanism of the ink film 43 conveying device becomes complicated. FIG. 4 shows a system in which one line is driven at the same time, and the ink film 44 and the recording paper 2 are each wound into rolls and are combined on the thermal head 14. Ink film 44 is yellow Y4,
For example, A4 in the order of magenta M4 and cyan C4.
Each edition is colored in series. First, only the necessary portions of the A4 size are printed in yellow, and then the recording paper 2 is released from the thermal head 14 and returned. Print the following in magenta and cyan in the same way, and
Finish color printing. In this method, the recording speed is faster, but the mechanism is complicated because it is necessary to return the recording paper to its original position after each color is printed, and the disadvantage is that the device becomes larger and the power capacity becomes considerably large. .

The present invention has been made to solve the above-mentioned drawbacks and problems, and it realizes a transfer-type thermal recording device that has a simple mechanism for conveying the thermal transfer sheet and recording paper, can downsize the entire device, and has good image quality. It is intended to.

In order to achieve the above object, the gist of the present invention is to provide a thermal transfer sheet that is subdivided into a plurality of color bands and is conveyed one color band at a time, and a recording paper that is conveyed in the same direction as the thermal transfer sheet. , a thermal head that simultaneously transfers a plurality of color bands of the thermal transfer sheet onto the recording paper each time the thermal transfer sheet is conveyed by one color band, and when recording of the plurality of color bands of all color bands is completed; The present invention resides in a transfer type thermal device characterized in that it is configured to feed recording paper in the plurality of color bands.

The present invention will be explained below based on the drawings.

FIG. 5 is a perspective view of a main part of a basic device for explaining an embodiment of a transfer type thermal recording device according to the present invention. 2 is a recording paper, and 45 is a thermal transfer sheet having a width corresponding to the width of the recording paper, both of which are wound into a roll. Reference numeral 15 denotes a thermal head on which the recording paper and the thermal transfer sheet 45 are combined, and is composed of a plurality of heating elements (for example, 16 elements/2 mm) arranged in a vertical row.
Reference numerals 51, 52, and 53 constitute a conveying means for conveying the thermal transfer sheet 45 and the recording paper 2 in a fixed vertical direction (in the direction of the arrow in the figure).
As shown in FIG. 6, the thermal transfer sheet 45 has a repeating pattern of a plurality of colors (herein, yellow, magenta, cyan, and black (hereinafter referred to as Y, M, C, and B, respectively)) in series in the vertical direction (transport direction). (color band). The length of one color in the vertical direction is equal to the length of the thermal head 15 in the vertical direction (also called recording length; for example, 2 mm), or is made longer than the recording length to avoid color mixing due to positional deviation.

FIG. 7 shows the scanning pattern of the thermal head 15. The thermal head 15 generates heat only in the part necessary for printing, and while transferring the ink on the thermal transfer sheet 45 to the recording paper 2,
scanned in the width direction.

FIGS. 8A to 8E show the process of multicolor printing.
When the thermal transfer sheet 45 is fed in the vertical direction (FIG. 8A), each color is transferred to an area 21 of the recording paper 2 corresponding to the horizontal scanning of the thermal head 15. First, the Y portion of the thermal transfer sheet is transferred to the area 21 of the recording paper (FIG. 8B). Next, while the recording paper remains in the same position, the thermal transfer sheet is fed by the length of one color in the vertical direction to transfer the M portion (FIG. 8C).
As a result, in area 21 of the recording paper, Y, M, M+Y
(red is a mixture of magenta and yellow). If you do the same for each color C and B (Fig. 8 D, E), the area 21 of the recording paper will have Y,
A total of seven colors are printed: M, C, B, Y+M, M+C (blue, which is a mixture of magenta and cyan), and C+Y (green, which is a mixture of cyan and yellow) (FIG. 8E).
Next, by feeding the recording paper 2 by the recording length and repeating the above steps, it is possible to print on recording paper of the required length (A4, etc.).

9 and 10 are explanatory diagrams for explaining the first embodiment of the present invention, in which four color bands are simultaneously scanned by a thermal head 19 corresponding to the four color bands. For example, 64 heating elements are arranged in one column in the vertical direction, and 16 elements are assigned to each color band. In this case, the longitudinal length of each color band of the thermal transfer sheet 49 is set equal to the recording length (for each color). First, recording paper 2 corresponding to the heating element corresponding to each color.
Y, M, C, and B of the thermal transfer sheet 45 are transferred to each of the areas 221, 222, 223, and 224 of 2, respectively. Next, the thermal transfer sheet 49 is fed by the recording length (for each color), and M, C, B, and Y are further transferred to each area 221, 222, 223, and 224, respectively. This result area 221
are printed in Y, M, and Y+M colors, and the area
222 is printed in colors M, C, and M+C, area 223 is printed in C and B, and area 224 is printed in B and Y. If you repeat 2 steps in the same way, areas 221, 222, 223, and 224 will all have
Y, M, C, B Y+M, M+C, C+Y printing is completed in a total of 7 colors. Next, advance the recording paper by four times the recording length (for each color) (total vertical length of the thermal head) and repeat the above steps to print on the required length of recording paper (A4, etc.). .
In this case, the number of scans of the thermal head is reduced to 1/4 compared to the case of the apparatus shown in FIG. 7, so there is an advantage that the recording speed is about 4 times faster. Furthermore, since recording of multiple color bands is performed simultaneously and the recording paper is stationary during this time, color shift due to errors in feeding the recording paper is less likely to occur. Compared to the case where the recording paper is fed every time one color band is recorded, as in the case of FIG. 7, the frequency of color misregistration, color mixing, etc. is reduced to approximately 1/4.

In addition, if the accuracy of the color-coding dimensions for each color of the thermal transfer sheet is insufficient, prepare two sets of recording heads and two sets of repeating patterns of the thermal transfer sheet, and operate them so as to complement each other (for example, one set for each set). (For example, have each row accept two colors, so that one group fills in the gaps between the records of the other group.)
This can improve color mixture, color misalignment, etc.

FIG. 11 is a partially cutaway perspective view for explaining a second embodiment using a thermal head 60 having heating elements in a matrix shape having a width corresponding to the width of the thermal transfer sheet. The thermal head 60 has a resistor 63 with an upper electrode 61 and a lower electrode 62.
The heating element corresponding to the position on the matrix selected by the upper surface electrode 61 and the lower surface electrode 62 generates heat and records data. According to this method, as in the first embodiment, each heating element is made to correspond to a plurality of colors of the thermal transfer printer in the vertical direction, and scanning of the thermal head is not required.
The recording speed can be further improved.

It is preferable that the thermal transfer sheet used in each of the above embodiments be based on a material such as capacitor paper that is strong and resistant to heat.

Furthermore, in each of the above embodiments, thermal transfer sheets of four colors, Y, M, C, and B, were used; however, the present invention is not limited to this;
Using three color thermal transfer sheets M and C, B is Y+M
It may also be created as +C (black created by mixing yellow, magenta, and cyan).

In addition, in each of the above embodiments, there is no reverse movement when conveying the recording paper or thermal transfer sheet, and it only needs to be conveyed in a fixed direction, so the mechanism of the conveying device can be simplified, and the advantage is that there is less color shift and color mixing. (Accurate positioning is possible using a stepping motor etc. for each feed). Further, the width of the recording device does not become bulky.

Furthermore, since the recording length (for each color) is short (especially compared to the conventional example shown in FIG. 4), there is also the advantage that there is less color shift and color mixing due to expansion and contraction of the recording paper or thermal transfer sheet. Moreover, since recording for one line is performed using the width of multiple thermal elements, recording with little color shift or color mixing can be achieved without having to leave much margin for each color band on the thermal transfer sheet relative to the width of the thermal element for one color. The recording efficiency is also excellent. Furthermore, the production of the thermal transfer sheet is relatively easy.

As described above, according to the present invention, it is possible to realize a transfer-type thermal recording device that has a simple mechanism for conveying the thermal transfer sheet and recording paper, can downsize the entire device, and has good image quality with less color shift and color mixing. .

[Brief explanation of drawings]

1 to 4 are explanatory diagrams of the principle of a conventional transfer-type thermal recording device, FIG. 5 is a perspective view of the main part configuration of the basic device for explaining an embodiment of the present invention, and FIG. 6 to FIG. 8 is an explanatory diagram of the apparatus shown in FIG. 5, FIGS. 9 and 10 are explanatory diagrams of the first embodiment of the present invention, and FIG. 11 is an explanatory diagram of the second embodiment of the present invention. FIG. 3 is a partially cutaway perspective view. 19, 60...Thermal head, 49...Thermal transfer sheet, 2...Recording paper.

Claims (1)

[Scope of Claims] 1. A thermal transfer sheet that is subdivided into a plurality of color bands and is conveyed one color band at a time, a recording paper that is conveyed in the same direction as the thermal transfer sheet, and a thermal transfer sheet that is conveyed one color band at a time. and a thermal head that simultaneously transfers a plurality of color bands of the thermal transfer sheet to the recording paper each time the thermal transfer sheet is transferred, and is configured to feed the recording paper by the plurality of color bands when recording of the plurality of color bands of all the color bands is completed. A transfer type thermal recording device characterized in that it is configured as follows. 2. The transfer type thermal recording device according to claim 1, wherein the thermal head has at least one row of heating elements.