JPS6083862A - Multi-color transfer type thermal transfer printing apparatus - Google Patents

Abstract

PURPOSE:To reduce color shift, by providing a means for shifting a recording start position, when an average recording feed amount per one raster is changed, corresponding to the change amount thereof. CONSTITUTION:A photosensor 16 for detecting the passage of the leading end of recording paper 11 is provided to this side of a thermal head 10A for performing recording and a photosensor 17 for detecting the rear end of the recording paper 11 is provided behind a thermal head 10B. The output signals of these sensors 16, 17 are inputted to a recording start time control circuit 18 and a recording start position is shifted corresponding to the change in an average recording feed amount.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is capable of recording multiple colors by sequentially passing a recording paper through each recording part and aligning the colors. The present invention relates to a single-pass type multicolor transfer type thermal recording device that performs recording.

[Prior art]

The transfer type thermal recording device can record characters in the desired color by simply replacing the ink donor film with the desired color. This method is attracting attention because it is possible to easily perform multicolor recording by using different colors of the ink donor films in each stage. For example, as shown in FIG. 1, recording units consisting of a pack roller 2 and a thermal head 3 are arranged in columns corresponding to each color of yellow, magenta, and cyan through a paper guide 1, and the ink in each recording unit is The colors of the donor film 4 are assumed to be independent, with yellow recorded in the first recording section, magenta recorded in the next recording section, and cyan recorded in the next recording section; sequentially. By doing so, multicolor recording using a combination of yellow, magenta, and cyan can be realized on the recording paper 5.

By the way, in such a single-pass type multicolor thermal recording device having a plurality of recording sections, it is necessary to align the recording positions between the respective recording sections to prevent color misregistration. For this reason, conventionally, means have been used to suppress the amount of deviation between each recording section between the average advance of the recording paper per raster in the initial state 5 (i) and the recording start position on the recording paper to a certain value or less. If the average feed amount of the recording paper changes due to changes, etc., there will be little color shift at the beginning of the recording, but large color shift will occur near the end of the recording, resulting in a reduction in image quality. .

[Purpose of the invention]

The present invention has been made in view of the above-mentioned conventional drawbacks, and an object of the present invention is to provide a multicolor transfer type thermal recording device that can reduce color shift caused by fluctuations in the average feeding amount of recording paper.

[One configuration of the invention]

The present invention provides means for shifting the recording start position in accordance with the change meter when the average recording paper feed threat per rusk changes over time and the total recording length changes in a certain recording section. This minimizes the amount of misalignment in the recording area and distributes the misalignment to the leading edge and trailing edge of the recording to make color misalignment less noticeable.

〔Example〕

Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a configuration diagram showing an embodiment of the present invention, in which each recording section includes a thermal head], OA, 1. OB,
Drive rollers 13A, 13B that face the thermal helix IOA, IOB and feed the recording paper 11 and ink donor films 12A, 12B (Iif2); supply rollers 14A, 1 that supply the ink donor films 12A, 12B;
4B, and winding rollers 15A and 15B that also perform winding. Note that the symbol A is used for the component of the second recording section, and the symbol B is used for the component of the second recording section.
It is shi. The recording paper 11 passes through these two recording units from the right side to the left side in the figure, but in front of the thermal head 10A that performs recording, the passage of the tip of the recording paper 11 is detected. A photosensor 16 is provided to detect the trailing edge of the recording paper 11, and a photo sensor 17 is provided behind the thermal radar 12B to detect the trailing edge of the recording paper 11.The output signals of these sensors 16 and 1.7 are used to control the recording start timing. circuit 18
is input.

The operation will be explained below. 11 In the second recording section, the recording paper 11 is made of ink donor films 12A and 12B.
Along with the drive roller 13A.

13 B. At this time, [9] The difference in the amount of recording paper movement per rotation angle for one raster due to the difference in diameter between the live rollers 13A and 13B is determined by the stepping motor 19A per raster applied to each recording section.

By thinning out or increasing the number of 19B steps at certain intervals, the effect is initially set in advance so that it has a minimum value with respect to the total recording length)1. I'm here.

Then, when a piece of recording paper is conveyed to the first recording section by a paper feeding mechanism (not shown), the photo sensor 6 detects the passage of its leading edge. Then, the timing at which the recording paper 8 reaches the recording position of the thermal head IOA is calculated by the recording start timing flt control circuit 18 from the distance between the drive roller 13A and the photosensor 16, the conveyance speed of the paper feeding mechanism, and the leading edge detection signal. . Then, based on this calculation result, the stepping motor 13A is controlled so that recording is started from a predetermined position a certain distance away from the leading edge of the recording paper. Note that the term "recording" as used herein includes recording of white information. On the other hand, the recording start time in the second recording section is determined by the distance between the recording sections, as described above. As described above, the color shift in the initial state is set to the minimum.

By the way, if the device is used repeatedly in this state, the Citripro rollers t3A, 13B will change over time.
This increases the number of slips between the recording paper 11 and the recording paper 11, resulting in a difference in conveyance amount between the recording sections. In this case, when the conveyance amount of the recording section of the cylinder 1 becomes smaller, most of the recording paper 11 is conveyed to the two recording sections at the same time, so the difference in conveyance amount is the difference between the recording sections. Although it is small as it is only the amount that depends on the distance, if the amount of conveyance is smaller in the second recording section, the difference in conveyance amount will affect the entire recording length.

Therefore, the recording start timing control circuit j8
Measure the difference in timing between the trailing edge detection signal of the recording paper 11 obtained from 6 and the leading edge detection signal obtained from the photosensor 17, and calculate the average decrease in feed speed based on the difference from the normal state. Then, the shrinkage of the total length of the recording paper in the second recording section is calculated.

Based on this calculation result, the chipping motor J-9A is operated so as to shift the recording start time to a point in time that is ahead of the time.
, 19 B is controlled to suppress the maximum amount of recorded color deviation to about half of the deviation of recording paper feed ffi.

By doing so, it is possible to reduce color shift due to fluctuations in the average feeding amount of recording paper, and it is possible to improve image quality.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the recording start position is corrected according to the change in the average feeding amount of the recording paper in a certain recording section, so the color between each recording color is corrected. The deviation can be reduced and the image quality can be improved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the general configuration of a multicolor transfer type thermal recording apparatus, and FIG. 2 is a diagram showing the configuration of an embodiment of the present invention. 10A, IOB... Thermal head, 1]... Recording paper, 12A, 12B... Ink donor film, 13
A, 13B...drive roller, 14A, 14B...
・Supply roller, 15A, 15B... Winding roller, 1
6, 17... Photo sensor, 18... Recording start timing control circuit, 19A, 19B... Stepping motor. Figure 2 8

Claims (1)

[Claims] In a multicolor transfer type thermal recording device that is equipped with a plurality of recording sections with different recording colors and performs multicolor recording by passing recording paper through each recording section in order and superimposing the colors, in the sub-scanning direction of each recording section] A multicolor transfer type thermal recording device characterized by comprising a control means for correcting the recording start position from the leading edge of the recording paper in accordance with the average recording paper conveyance amount of the rask.