JPS58203466A - Image synthesizing method - Google Patents

Abstract

PURPOSE:To attain an image synthesizing method where the positional deviation is eliminated with an easy operation and a synthesized image is superior in uniformity of image quality, by performing the exposure of the image of the second original, the formation of a letent image, and the development after charging again a photoreceptor having a fixed toner image of the first original. CONSTITUTION:A photoconductive sheet 10 is charged electrostatically by a charger 4 after supporting around a rotary drum 1, and the image of the first original on a platen 3 illuminated with an original illuminating lamp 14 is projected onto the photoconductive sheet 10 through a projection lens 2 to form an electristatic latent image. This latent image of the first original is developed by a developing machine 5 and is fixed onto the photoconductive sheet 10 to obtain a toner image. Next, the second original is placed on the platen 3 instead of the first original, and the photoconductive sheet 10 which carries this fixed toner image and is wound around the rotary drum 1 is charged again by the charger 4, and the image of the second original is projected onto the photoconductive sheet 10 by the original illuminating lamp 14 and the projection lens 2, and thus, a synthesized electrostatic latent image of the first and the second originals is obtained on the photoconductive sheet 10, and next, a fixed synthesized imagen of them is obtained on the sheet 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image composition method for copying images of a first original and a second original onto the same recording medium using electrophotography, and particularly to an image composition method using electronic printing.

Conventionally, the so-called 7-ohm overlay method, in which ordinary electrophotographic copying is performed with two types of originals superimposed on a document table, has been well known as one of the painter's composition methods using electrophotography. In this method, latent f-images corresponding to two types of originals are simultaneously formed on the photoconductor, so there is no problem in terms of uniformity of composite image density, but one of the originals is limited to a transparent original, and This method has drawbacks such as the fact that positional deviations are likely to occur, resulting in image deviations of one composite image, and the trouble of having to superimpose the originals for each copying operation.

Another method is to sequentially form a images corresponding to two types of originals on a photoreceptor and overlap them. For example, there is a method in which a two-layer laminated photoreceptor with different photosensitive ranges is used, and image exposure is performed after the charging process in which the wavelength range is changed for each document, or the method shown in Japanese Patent Application Laid-Open No. 8717-1983. There is a method in which a photoreceptor having a transparent insulating layer provided thereon is sequentially subjected to charging and simultaneous 11th image exposure, charging and simultaneous second image exposure, and whole surface exposure. These methods do not limit the number of originals or complicate overlapping of originals; however, because a special photoreceptor or process is used, the device configuration inevitably becomes complicated.

In addition to the poor uniformity of the image quality of the composite image, when it is desired to superimpose a number of second document images with different contents on a constant first document image such as a line or frame, the latent image of both documents may be There is the complexity of having to repeat the forming process each time.

The object of the present invention is to provide an image synthesis method that eliminates the drawbacks of conventional methods, and that makes it possible to obtain a composite image with simple operations, no positional deviation, and excellent uniformity of image quality. For the purpose of providing law.

A further object of the present invention is to provide an image composition method for forming a composite image by repeatedly using the same format manuscript and replacing only the other manuscript.

The present invention achieves the above object as follows.

That is, first, the electrophotographic photoreceptor is charged, and then the image of the first original is exposed. Next, the latent image of the first document is developed with toner to form a toner image, which is fixed to obtain a fixed toner image of the first document on the photoreceptor. Next, after recharging the photoreceptor having this fixed toner image, image exposure of the second original is performed, and an electrostatic layer @ in which the images of the first original and the second original are combined is formed on the photoreceptor. The electrostatic a image is developed to obtain a composite toner image, and then this composite toner r* is transferred and fixed to obtain a composite image.

By cleaning the residual toner on the photoreceptor after transfer and performing the above process on a different second original (that is, the process after image exposure of the second original), it is possible to combine the first original with the second original, which is different from the first original. Images can be obtained in a similar manner.

Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a diagram showing an example of an apparatus used in the present invention,
In the figure, 1 is a rotating drum, 2 is a projection lens, 3 is a document table, 4
is a charger, 5 is a developing device, and 6″′□i.

1 is a transfer corotron, 7 is a flash fixing device, 8 is a cleaning device, 9 is a hot roll fixing device, 10 is a photoconductive sheet, 11 is a transfer paper, 12 is a paper output tray, 13 is a uniform exposure rung, and 14 is an original illumination 15 is a cleaner lamp; 16 is a single conductive sheet inlet; and 17 is a photoconductive sheet discharge tray.

Next, the operation of this device will be explained.

A case will be explained in which the first document is a format and the second document is a document with variable contents such as numbers and characters.

First, after the photoconductive sheet 10 is wrapped around and supported by the rotating drum 1, it is charged by the charger 4, and further illuminated by the document illumination lamp 14, the first document on the document table 3 is placed on the projection lens 1.
is projected onto the photoconductive sheet 10 via the photoconductor to form an electrostatic latent image. Next, the latent image corresponding to the first document is visualized by the developing device 5, and then melted and fixed onto the photoconductive sheet 10 by the flash fixing device 7, thereby obtaining a fixed toner image.

Next, a second original is placed in place of the first original on the original platen 3, and the photoconductive sheet 10, which carries the above-mentioned fixed toner image and is wound around the rotating drum 1, is again charged with a charger. 4
The second original image is projected by the original illumination rung 14 and the projection lens 2, and an electrostatic art in which the first original and the second original are combined is obtained on the photoconductive sheet 10.

Next, this composite latent image is visualized in the developing device 5, and then the transfer paper 11 is sent to the transfer section in synchronization with the rotation of the rotating drum 1, and the toner image on the photoconductive sheet 10 is formed by the transfer corotron 6. The image is transferred onto a transfer paper 11 and further transferred to a heat roll fixing device 9.
The image becomes a fixed image, and is guided to the paper discharge tray 12 to become a copy.

On the other hand, the residual toner on the photoconductive sheet 10 after the transfer is cleaned by the cleaning device 8, and -th composite image copying is completed. The fixed toner image corresponding to the first original remains on the photoconductive sheet (photoconductive sheet) 10, and when compositing with several different second originals from now on, the second original on the original table is simply The above steps of recharging, second original image exposure, development, transfer/fixing, and cleaning may be performed by sequentially replacing .

Known charging devices and image exposure devices can be used in the present invention.

The photoconductive sheet 10 is made of ZnO1CdS on a conductive support.
It is possible to use a photosensitive layer coated with a photosensitive layer containing photosensitive particles dispersed in a resin, or coated with an organic photosensitive material such as polyvinylcarbazole-trinitrofluorenone (PVK-TNF). belt shape,
It can be used in any shape such as a scroll shape. When it is made into a sheet, it is possible to reuse the photoconductive sheet carrying the fixed toner image by ejecting it from the device and storing it. Further, when the photoconductive sheet is formed into a scroll shape, the complexity associated with feeding and discharging the photoconductive sheet is eliminated, and the apparatus can be simplified.

What is the method of phenomenon, such as the conventionally known method, such as the magnetic brush method or the cascade method? It is also possible to use two-component type or -component type of developer.

A pressure fixing method or a heat fixing method is used to fix the toner image corresponding to the first document (image) on the photoconductive sheet 10. The photoconductive sheet 1 carrying the fixed toner image
0 continues to be recharged, so the photoconductive sheet 10
Any fixing method may be used as long as it does not cause a change in the chargeability of the toner. Heat roll fixing method is used as heat fixing method.
Although flash fixing methods may be mentioned, it is preferable to use a flash fixing device because it simplifies the device and causes less deterioration in image quality when the toner is fixedly attached (7). A schematic cross-sectional view of a typical flash fixing device is shown in FIG.

In the figure, 18 is a flash rung, and 19 is a reflector.

The position of the flash lamp 18 and the shape and position of the reflector 19 are such that the toner image on the photoconductive sheet 10 wound and supported on the rotating drum 1 can be fixed efficiently and uniformly. It consists of two ellipsoid parts that share one focal point, and 7 lattice rungs 18 are arranged at this shared focal point and point part, and the recording surface is located near the other focal point of each □ of the second ellipsoid part. This is what was installed.

The device for recharging and the device for exposing the image of the second document may be the same as that used for forming the fixed toner image corresponding to the first document, or another device may be provided.

The state diagrams on the photoconductive sheet during the formation and visualization of electrostatic latent images corresponding to the first and second originals are shown in 3(1) to (3).
i) Shown in the figure.

In the figure, (a) is the charging process, (b) is the first original image exposure process, (c) is the developing process, (d) is the fixing process, (e) is the recharging process, and (, f) is the first original image exposure process. 2) indicates the original image exposure process, -) indicates the reproduction process, (h) indicates the transfer process, and 0) indicates the toner fixation process on the transfer paper. Further, 20 indicates toner particles, 21 indicates a fixed toner f image, and 22 indicates a toner image on the transfer paper.

The first. formed by the steps (,) to (d). The photoconductive sheet 10 carrying the fixed toner image corresponding to the original is recharged in steps (,) and exposed to a second original image in step (f), thereby forming a photosensitive layer of the photoconductive sheet 10. Charges in bright areas flow out through the conductive support, while charges in dark areas are retained. On the other hand, the photoconductive sheet 10
The toner image area fixed on the top acts as an optical shielding mask for the photoconductive layer directly below it, so that the charge is retained almost unaffected by the bright and dark areas caused by the exposure of the second original image. Ru. In this state, the reproduction process (h)
A copy of the composite image is obtained by sequentially performing the transfer step (i) and the fixing of the toner onto the transfer sheet (i).

Figure 4 shows the first manuscript (@) and the symbol ・
This figure shows that by combining the second document (b) representing variable content such as characters using the method of the present invention, a composite image copy as shown in (C) can be obtained.

As a method for cleaning the toner remaining on the photoconductive sheet 10 in the present invention, conventionally known fur brush methods, magnetic brush methods, etc. can be used.

Further, as a method for removing the residual charge on the photoconductive sheet (10), conventional methods such as alternating current corona discharge and uniform exposure can be used.

As explained above, according to the method of the present invention, a composite image of uniform image quality with no positional deviation can be obtained by simple operation. FIG. The figure is a schematic sectional view of an example of a flash fixing device used in the method of the present invention, Figures 3 (11) to (1) are explanatory diagrams sequentially showing the steps of the method of the present invention, and Figures 4 (a) to (c). ) represent examples of a first original image, a second original image, and a composite image, respectively.

Symbols in the figure: 1... Rotating drum; 2... Projection lens; 3... Original table; 4... Charger; 5... Developing device; 6... Transfer corotron; 7... Flash fixing device; 8... Cleaning device; 9... Heat roll fixing device: 10...
Photoconductive sheet; 11... Transfer paper; 12... Paper ejection tray; 13... Uniform exposure lamp; 14... Original illumination rung; 15... Cleaner lamp; 16... Sheet inlet ;17...7-t discharge tray;18...7
Lash lamp; 19...Reflector; 20...Toner particles; 21...Fixed toner (a; 22...Fixed toner image on transfer paper.

Representative Patent Attorney (8107) Kiyotaka Sasaki (and 3 others) Figure 1 = 11- Figure 3

Claims (1)

[Claims] After charging the electrophotographic photoreceptor, image exposure of the first original is performed to obtain an image a, and this latent image is developed to form a toner acid of the first original, which is fixed and the image of the first original is deposited on the photoreceptor. After forming a fixed toner image and then recharging the photoreceptor carrying the fixed toner image, image exposure of the second document is performed to form a composite electrostatic latent image of the first document group and the second document image. A one-image synthesis method characterized by developing a synthetic electrostatic latent image to obtain a toner image, transferring this toner image to a transfer material, and then fixing it to obtain a synthetic image.