JPS62243466A - Multicolir thermal transfer recorder - Google Patents

Abstract

PURPOSE:To reduce the inconvenience that a recording position differs form each color by providing an end face detection means for detecting an end face of recording paper and a means for controlling the recording position of a thermal head by means of the end face detection means. CONSTITUTION:A thermal head 101 is a recording head provided with plural heat resistors as heat elements, an image sensor 130 is provided with plural photodetectors and reads the end face image of the recording paper 120. A color sensor 102 detects the color of an ink sheet 121, outputs the result to the control section 103 and plural hot-melt or hot-subliming colors are painted sequentially on the sheet 121 in the carrying direction. The control section 103 uses the a roller 110 to carry the recording paper 120 in the forward direction, the recording by the 1st color member is executed and the end face information of the recording paper 120 is stored. Attended with the end of recording of the 1st color, the recording paper 120 is carried in the reverse direction and in recording the 2nd color member, the stored end face position information is called to control the recording position in the main scanning direction.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to multicolor thermal transfer recording in which a recorded image is obtained by thermally transferring coloring materials of three colors cyan, magenta, and yellow or four colors including black as a black plate. Regarding equipment.

2. Description of the Related Art A thermal transfer method is well known as a hard copy device for printing color images. For example, as shown in FIG. 6, such a multicolor thermal transfer recording device includes a thermal head 101 provided with a plurality of heating resistors and a plurality of heat-melting or heat-sublimating resistors in the conveying direction (sub-scanning direction). an ink sheet 121 on which the coloring material is applied in the order of yellow, magenta, and cyan, for example; a recording paper 120 from which the coloring material is transferred to form a recorded image; and a recording paper 120.
, and ink sheet! A control unit 80 that controls the conveyance of 21
Consists of 3.

To perform recording, image signals are stored in a buffer memory, and the ink sheet 121 and recording paper 120 are moved to the roller 110.
The image signal corresponding to the coloring material on the ink sheet 121 is read out from the buffer memory, the thermal head 101 is driven, and the ink sheet 12
The color material on 1 is melted and transferred onto recording paper 120.

In this way, when recording corresponding to a single color material is completed, the pressure contact state of the thermal head 1011 ink sheet + 21, the recording paper 120, and the roller 110 is released, and the ink sheet 121 is transferred to the next color material of the thermal head 101. The recording paper 120 is conveyed by the color sensor 102 so that it is positioned below, and the recording paper 120 is conveyed so that the beginning of the area where the recording corresponding to the previous color material was performed is positioned below the thermal head. Next, with an image signal corresponding to the color material of the ink sheet 121,
Driving the thermal head, the above-mentioned ink sheet 121
, the recording paper 120 is conveyed to obtain a second color recording image. Similarly, 3 yellow, magenta, and cyan
A single color recorded image is obtained by superimposing recorded images of four colors, including color or black as a black plate.

Problems to be Solved by the Invention However, in the conventional multicolor printing apparatus described above, monochromatic images are recorded in an overlapping manner while reciprocating the recording paper 120. Another drawback is that the recording position is different for each coloring material.

The cause of the skewed feeding of recording paper +20 is (■), Thermal head 10! , Inc.) 121%
Recording paper! 20 and the roller 110 are in pressure contact,
Nonuniform pressure in the axial direction of the roller 110 (perpendicular to the conveying direction of the recording paper 120); (2) because the amount of color material transferred to the recording paper 120 differs depending on the image signal corresponding to the color material; , the frictional force of the recording paper changes, etc.

The present invention has been made in order to eliminate the above-mentioned drawbacks inherent in the conventional technology, and therefore, an object of the present invention is to provide a novel multicolor thermal transfer recording device with less color shift and good graphic reproducibility. It is about providing.

Means for Solving the Problems In order to achieve the above object, the multicolor thermal transfer recording device according to the present invention includes an ink sheet on which a plurality of color materials are applied for each color material in the sub-scanning direction, and an ink sheet coated with the ink sheet. a thermal head that heats and transfers the coloring material onto a recording paper; a recording paper as a copy medium onto which the coloring material is transferred; a recording paper transport means that moves the recording paper back and forth by the number of the coloring materials; The apparatus is configured to include means for detecting the end surface of the recording paper, and means for controlling the recording position of the thermal head using the detecting means.

EXAMPLE Below, a preferred embodiment of the present invention will be specifically explained with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. In FIG. 1, reference number 101 indicates a thermal head, and the thermal head 101 is a recording head provided with a plurality of heating resistors as heating elements. The image sensor 130 is provided with a plurality of photodetecting elements, and has a recording paper! Read the end face image of 20. The image sensor 130 includes, for example, a contact type image sensor and a light source. In other embodiments, image sensor 130 is CO
It consists of a D image sensor, a light source, and a lens.

The color sensor 102 detects the color of the ink sheet 121 and outputs it to the control unit 103. The ink sheet 121 is coated with a plurality of coloring materials having heat melting properties or heat sublimation properties -5= in the order of yellow, magenta, and cyan in the direction in which the ink sheet 121 is conveyed. The control unit 103 controls the recording paper 120
is conveyed in the forward direction by rollers 110.

The end surface position of the recording paper 120 is read by the image sensor 130 for each line that is conveyed in the forward direction, that is, recorded. The binarized output of the image sensor 130 is, for example, a portion where the bits are "1" for all pixels (k pixels to pixels) as shown in FIG. 2 in a certain line.
This indicates that the recording paper 120 is present. Here, k in FIG. 2 is defined as a pixel bit representing the pupil at the edge of the recording paper. First, referring to FIG. 5, consider the case where a first color material (for example, yellow) is to be printed.

Image signals Y and M1C are each stored in a buffer memo 501.
, 502, 503.

In order to record the first line (recording start point), the changeover switch 510 is connected to the a contact side, and the shift control circuit 504
Read out the Y pixel signal. The image signal input to the shift control circuit 504 is transferred as it is as a recording image signal 521 to the thermal head 101, and the first line is recorded. At this time, the end face position information 520 of the recording paper 120 read by the image sensor 130 is
! ! The data is stored in the memory 505 through the a-contact. Thereafter, the memory 505 stores the first line (recording amount point) to the Nth line (recording end point) as shown in FIG. 3(a).
Record paper until now! Twenty end face position information (k) is accumulated.

Upon completion of recording of the first color, the recording paper 120 is conveyed in the reverse direction to the first line (recording start point). Further, the ink sheet 121 is conveyed by the color sensor 102 to a position where a second color material (for example, magenta) can be recorded.

Next, consider a case where a second color material (for example, magenta) is recorded.

In order to record the first line (recording start point), the changeover switch 510 is connected to the b contact side, and the shift control circuit 504
The M image signal is read out. The end face position information 520 of the recording paper 120 read by the image sensor 130 is input to the comparison circuit 50G through the b contact of the fifth changeover switch (FIG. 3(b)). On the other hand, the first line information of the edge surface position information of the recording paper 120 stored in the memory 505 when recording the first color (yellow) is read out, and the comparison circuit 50
6, and the difference between the two (see FIG. 4) is input to the shift control circuit 504. The shift control circuit 504 shifts the recording image signal 521 by +1 according to FIG. 4 and transfers it to the thermal head +01.

Therefore, the position of the image recorded by the thermal head 101 moves by +1, but the edge surface position of the recording paper 120 moves by +1.
Since the two colors have moved by 1, they are canceled out in the end, and the recording positions of the first color and the second color in the main scanning direction (the axial direction of the roller 110) coincide.

Thereafter, recording is performed in the same manner from the first line (recording start point) to the Nth line (recording end point). Furthermore, recording paper 1
20 and the ink sheet 121 are conveyed by the color sensor to a position where the third color material (cyan) can be recorded.

In the same way, cyan and then black recording is performed, completing one sheet of color recording.

In addition, in FIG. 5, the recording paper for the first color +20
The memory 505 that stores end face position information of the recording paper! 2
This is not necessary if the end face of the recording paper 120 is ideally cut in a straight line, but in reality it is jagged, so even if the recording paper 120 is conveyed ideally straight, the recording paper 120 A memory 505 is provided because the end face position information changes and it is assumed that the conveyance position has changed.

In this embodiment, a platen driving method using the rollers 110 is shown, but it is needless to say that the method is not limited to a transport method such as a transport method using a capstan roller.

Effects of the Invention As detailed above, according to the present invention, a means for detecting the edge of the recording paper is provided, and a means for controlling the recording position of the thermal head based on information on the edge surface position of the recording paper is provided. Even if the paper is skewed, the recording position on each recording line can be kept within at least one dot.
This has the effect of alleviating the problem of different recording positions for each color.

10-

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a multicolor thermal transfer recording device according to the present invention, FIG. 2 is a diagram showing output waveforms of the recording paper edge detection means, and FIGS. 3(a) and (b) are A diagram showing the output (position information) for each line of the recording paper edge detection means,
FIG. 4 is a diagram showing the difference in the edge position of the recording paper for the first color and the second and subsequent colors, FIG. 5 is a diagram showing the configuration of the control section of the present invention, and FIG. 6 is a diagram of the conventional multicolor thermal transfer recording apparatus. Diagram showing the configuration, No. 7
The figure shows an example of recording by a conventional multicolor thermal transfer device. 101, , thermal head, 102, ,
, a color sensor that detects the color of the coloring material of the ink sheet, 103
, . , control unit, 110', , platen roller, 12
0, . , recording paper, 121, , ink sheet coated with coloring material), 130. , , Image sensor for detecting the edge position of the recording paper, 501.502.503 , , Buffer memory for accumulating image signals, 504 , , Shift control circuit, 505 , , Accumulating the edge position information of the recording paper Le, +'! lJ, 50B, , comparator, 510
1511, . Changeover switch, 520, , Recording paper edge position information, 521, , Recording image signal to be transferred to the thermal head, 803, 0. Conventional control unit patent output NEC Co., Ltd. Representative Patent attorney Yutabe Kumagai

Claims (1)

[Claims] An ink sheet coated with a plurality of color materials for each color material in the sub-scanning direction, a thermal head that heats the ink sheet and transfers the color material to recording paper, and a recording medium as a copy medium to which the color material is transferred. In a multicolor thermal transfer recording device comprising paper and a recording paper conveying means for reciprocating the recording paper by the number of color materials, an edge detection means for detecting an edge of the recording paper; 1. A multicolor thermal transfer recording device comprising means for controlling the recording position of a thermal head.