JPS5973972A - Color electrostatic printing apparatus - Google Patents

Abstract

PURPOSE:To prevent the generation of color shift even in multi-coloration, by constituting the titled apparatus so as to be capable of conveying recording paper to both positive and reverse directions in such a state that both ends of the recording paper are grasped while successively arranging a multi-stylus head, a plurality of developing devices and a fixing device. CONSTITUTION:Electrostatic recording paper 7 is grasped at both ends thereof by pintch rolls 12a, 12b and a back-up roll 12c to be conveyed to a positive direction shown by an arrow 9. At this time, an image signal for a first color (e.g., cyan) is supplied to a multi-stylus head 11 and an electrostatic latent image for the first color 1 is formed on the recording paper 7. Subsequently, said latent image is developed by a developing device 13 for the first color and the developed image is fixed by a fuser 16. In the next step, the recording paper 7 is reversely sent to a direction shown by an arrow 19 by conveying roll pairs 12a-12c and again conveyed to the positive direction shown by the arrow 9 in such a state that the leading end thereof is subjected to positional alignment. At this time, by the multi-stylus head 11 and a developing device 14, the formation and the development of an electrostatic latent image for a second color (e.g., magneta) are performed and the developed image is fixed by the fuser 16. Similarily, recording for a third color (e.g., yellow) is performed and three-color images are stacked to obtain a natural color image.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color printer device.

Recording with an electrostatic printer not only provides high image quality, but also allows for halftone expression, and even though the recording paper is special paper, it looks almost the same as regular paper. It also has the characteristic of not having any problems in storage.For this reason, we have traditionally taken advantage of the above-mentioned ↓7)% characteristics.
Various attempts have been made to obtain color-printed images by electrostatic recording. One of the known methods is to arrange a plurality of electrostatic recording printing units of different tones in several stages along the conveyance path of recording paper, and record each color one after another in a layered manner.

The first part is a diagram showing a schematic configuration of a conventional color electrostatic printer device. The electrostatic HC recording paper 7 is pulled by a pair of feed rolls 8 and conveyed in the direction of an arrow 9.

The multi-stylus head 1, the developer 2 provided on the downstream side thereof, the gauze, and the user 3 provided further downstream thereof constitute an electrostatic recording printing section 10 for the first color.

The multi-stylus head 4, the developing device 5 provided downstream thereof, and the seven users 6 further provided downstream thereof constitute an electrostatic printing section 20 for the second color. In the conventional color electrostatic printer device having the above-mentioned configuration, the electrostatic recording paper 7 is conveyed at a predetermined speed in the direction of the arrow 9 by the feed row /l/8, and the first color 1
? Electrographic printing section 10 and second color electrostatic printing section 20
For example, if the first color electrostatic printing A5to records one line of red, and then the second color electrostatic printing section 20 records black, An image in two colors, red and black, can be obtained.1 Therefore, by adding an electrostatic recording printing section for a third color and performing overlapping recording using the three primary colors, it is possible to obtain a natural color print image. can.

However, in such a conventional device, the recording paper 7 is pulled by the feed roll 8, and there is a considerable gap between the feed roll 8 and the multicolor head 1.4 for each color. Because of this distance, the recording paper 7 tends to expand, contract, and meander in that area.

If the recording paper 7 expands, contracts, or meander as described above, no matter how precisely the multi-stylus heads for each color are positioned relative to each other, color misalignment will occur between the recorded images of each color, and the quality of the printed image will deteriorate. It has the disadvantage that it decreases.

The purpose of the present invention is to provide 11 colors that do not cause color shift even when multicolored. Our purpose is to provide an electronic printer device.

In order to achieve the purpose described in ^1■, in the present invention,
Conveyance [+-] The recording paper can be conveyed in both forward and reverse directions with both ends of the recording paper being held between the pair of rolls, and a multi-stylus head is disposed near the pair of conveyance rolls; Along the recording paper conveyance path, on the downstream side of the multi-stylus head, so as to face the recording paper,
The batter structure has at least two sets of developing devices and a foot attaching device arranged in sequence.

The present invention will be described in detail below with reference to the drawings.

FIG. 21 is a schematic front view of one embodiment of the present invention, and FIG. 3 is a left side view thereof. In addition, in these figures, the first
The same reference numerals as in the figure refer to the same parts.

One multi-stylus head 11 is silent 1ltI, I2
It is arranged so as to face the transport path of the recording paper 7, and
%Q 1 A pair of conveyor wheels for conveying the electrostatic recording paper 7 in forward and reverse directions is arranged near the multi-stylus rod 11.

As is clear from the figure, the conveyor roll pair carries the electrostatic recording paper 7.
0 Pinch rolls 12m in contact with both edges and conveying it
, 12b, and a backup roll 12c disposed at 5, facing each of the bottles 12a+12b, and sandwiching the electrostatic recording paper 7 therebetween.

In the examples shown in FIGS. 2 and 3, the position where the electrostatic recording paper 7 is sandwiched between the pair of transport rolls 11 and 12a and 12e is adjusted so that it almost coincides with the position where the electrostatic latent image is formed by the multi-stylus head 11. In other words, the pinch roll 12a,
Although the configuration is such that the multi-stylus controller 11 is positioned approximately in the center between the rotating shafts of the stylus 12b, this is not necessarily required (7 is also not necessary, and there may be a gap between the two). Of course.

Yopuko, iiQ F + self binbu ri -k 12a
, 12b 1 or at least both ends of the bank-up r1-rule 12c are preferably formed of a hard material and have a roughened surface 1. If this is done,
As will be described later, it is possible to prevent slips from occurring when the electrostatic recording paper 7 is transported in the forward and reverse directions.

The downstream side of Rad 11 to the Marv stylus (t in Figure 2,
On the right side), for example, developing units 13 to 15 for each hue of cyan, magenta, and yellow are arranged in eleventh order along the conveyance path of the electrostatic recording paper 7, and further, the developing units 13 to 1
A hooder 16 (for example, a flash lamp) is disposed downstream of the hood 50 .

During operation, both ends of the electrostatic recording paper 70 are held between the vinyl rolls 12a and 12b and the backup roll 12c, and are conveyed in the forward direction shown by arrow 9.

At this time, an image signal for the first color (for example, cyan) is supplied to the multi-stylus heater 11 according to an appropriate method, and an electrostatic latent image for the first color is formed on the electrostatic recording paper 7. is formed.

As is well known, the electrostatic latent image is formed as the electrostatic recording paper 7 is conveyed in the forward direction (rightward in FIG. 2).
The image is developed by the first color developer +3 and fixed by the fuser 16.

When the formation, development, and fixing of the first color electrostatic latent image are completed, the electrostatic recording paper 7 is moved by the transport roll pairs 12a to 12e.
1 is transported backward in the direction of arrow 19, and then transported again in the forward direction shown by arrow 9 with the leading end aligned.

When the electrostatic recording paper 70 is conveyed in the forward direction for the second time, the multi-stylus head 11 and the developing device 14 also form an electrostatic image for the second color (for example, magenta).
Development is performed and further fixing is performed by a fuser 16.

When the electrostatic latent image formation, development, and fixing of the second color are completed, the electrostatic recording paper 7 is conveyed in the opposite direction again, and recording is performed in the third color (for example, yellow) in the same manner as described above.

By the above operations, images in three different tones are superimposed and recorded on the electrostatic recording paper 7, and a natural color image is obtained.

. As is clear, by varying the number of developing units, it is possible to obtain a multicolor image 1c other than three colors.
Next, we will explain an experimental example conducted by Nagisa, the inventor of the present invention.

As the multi-stylus head 11, an 8-dot/gate multi-stylus head was used. Vinci roll 12
A and 12b are made of alumina ceramic with a roughened surface, and are still attached to the back "1 knob roll 12".
As c, a rubber one was used.

:! The Il imagers 13 to 15 include cyan, magenta,
Four sets of yellow and black were lined up along the paper transport path, and in accordance with the usual method, the 1st toner of each tone was supplied by a magnetic roll and developed. As the user 16, a flash lamp was used.

The process for obtaining color prints with this device is as follows.

When the electrostatic recording paper 7 is conveyed in the forward direction indicated by the arrow 9, a cyan Yf electrostatic latent image is first formed by the multi-stylus head 11.

Next, development with cyan toner is performed 1, and the cyan toner image is transferred to the recording paper 7 by the user 16.
will be established.

At this point, the vinyl rolls 12a and 12b are conveyed in the reverse direction, and the recording paper 7 is conveyed in the direction of the arrow 19, returning to the position at the start of recording.

Next, in the same manner as above, static I! for magenta color! A latent image is formed, and development and fixing are sequentially performed.

When the fixing of the magenta color image is completed, the recording paper 7 is returned to the starting point again.

By repeating 1 cess for each color of yellow and plaque, you can obtain 7 colored print images on recording paper.

In the present invention, color shift is minimized because the position of the multi-stylus head for obtaining an electrostatic latent image and the position of the pinch roll are close to each other in the direction of movement of the recording paper.

According to experiments by the present inventors, the time required to form an image of one color can be changed depending on the method of driving the multi-stylus 11, but it was possible to form an image in 1 to 10 seconds.

Therefore, the time required to form four-color images, that is, to form one color print, was 6 to 60 seconds, including the time required to convey the recording paper 7 in the reverse direction. therefore,
1 to 10 color prints were obtained in 1 minute.

The present invention allows the following modifications.

(1) %Q In order to increase the conveyance speed when the recording paper is conveyed in the reverse direction, the multi-stylus head structure may be slightly floated when the recording paper is conveyed in the reverse direction.

(2) In order to obtain a preferable image quality of a color intermediate, it may be preferable that the image of at least some tones is slightly shifted from the images of other tones1. It is preferable to slightly move the multi-stylus head in the direction perpendicular to the conveyance direction of the recording paper, to shift the timing of conveyance of the recording paper, or to arrange multiple sets of multi-styli so as to be slightly shifted from each other.

As is clear from the above description, according to the present invention, the electrostatic recording paper is always conveyed in the forward and reverse directions with both ends thereof being pinched between the pinch roll and the puncture roll, and moreover, only one The multi-stylus head of the is always pressed against the recording paper with a constant load1. Therefore, the slippage between the recording paper and the pinch roll is minimized and evened out, and a single recording paper can be moved forward or backward by the pair of transport rolls. Even when conveyance in this direction is repeated, the relative positional relationship (or phase relationship) between the recording paper and the multi-stylus is maintained constant.

Furthermore, according to the present invention, the position of the recording paper held between the transfer roll pair and the position of the recording paper recorded by the multi-stylus are close to each other (in the example of FIG. 2, they do not coincide). This prevents the recording paper from expanding and contracting or meandering during transportation, and color shift can be minimized. Therefore, according to the present invention, high-quality color images without color shift can be produced. In addition, since only one multi-stylus head is required, there is an advantage that a low-cost and compact printer can be obtained.

In addition, the color electrostatic printer device of the present invention can change the running speed of the recording paper as needed, and can also transport the recording paper in both forward and reverse directions. Multicolor blotting can be done, or specific prop inks can be overprinted on top of the 111 can print.

[Brief explanation of drawings]

FIG. 11 shows a schematic configuration of a conventional color silent printer (FIG. 1, FIG. 2 is a front view of an embodiment of the present invention, and FIG.
Figure t shows the left side view of Figure 2.1゜7...Electrostatic recording paper, 11...Multi-stylus,)
+ L2h...pinch roll, 12c...backup roll, 13-15...vL imager, 16...fuuser

Claims (1)

[Claims] (1) A pair of transport rolls that grips both ends of the recording paper and transports it in the forward and reverse directions; a multi-stylus head that is disposed facing the 8C recording paper near the pair of transport rolls; At least two sets of developing devices and fixing devices arranged sequentially in a direction facing the recording paper on the downstream side of the multi-stylus head along the conveying path, and the pair of conveying rolls are driven in forward and reverse directions. 1:2) A color still-jet 5 printer device, characterized in that the IJIJ feed roll pair contacts both ends of the IiC recording paper and conveys it, and the pinch roll that pinches the recording paper and conveys it. 2. The color electrostatic printer device according to claim 1, wherein the multi-stylus head is disposed between the rotation axes of both (Ill+) bin rolls and a backup roll facing the roll.