JPH0377970A - Color image forming method - Google Patents

Abstract

PURPOSE:To eliminate color discrepancy arising when images are formed in two or more colors such as red, green, blue and black by concurrently developing with two or more colors among yellow, magenta and cyan coloring grains possessing polarity opposite from the surface charges of an electrostatic image forming member. CONSTITUTION:When red, green, blue and black images are formed on the electrostatic image forming member, they are concurrently developed with two or more colors among yellow, magenta and cyan coloring grains possessing the polarity opposite from the surface charges of the electrostatic image forming member. While the electrostatic image forming member makes one turn, an image is formed at a time in one of the colors such as red, green, blue and black. By repeating this process, images of all colors are formed. Thus, color discrepancy does not arise when images are formed in two or more colors such as red, green, blue and black.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a color image forming method, and in particular, to the surface of an electrostatic image forming member, electrostatic latent image formation and development are repeated multiple times to statically deposit colored particles of different colors on the surface of an electrostatic image forming member. TECHNICAL FIELD This invention relates to a method of forming color images by polymerizing onto electroimageable members.

Conventional technology As a color image forming method as mentioned above, Japanese Patent Application Laid-Open No. 60-95
45 (I) and Japanese Unexamined Patent Publication No. 57-111572 are well known. An example of the color image forming method will be described below with reference to the drawings.

First, the method described in Japanese Unexamined Patent Publication No. 60-95456 will be explained. FIG. 2 is an operational flowchart of this method, in which 1 is an electrostatic image forming member and 3 is an exposure means.

First, the surface of the electrostatic image forming member 1 is charged, a first electrostatic latent image is formed by the exposure means 3, and the electrostatic latent image is developed to form a first toner image. do. Furthermore, the electrostatic image forming member 1 is charged one more time, a second electrostatic latent image is formed by the exposure means 3, and the electrostatic latent image is developed to form a second toner image. form.

In this way, repeated charging, image exposure, and development using a developer each time are performed, and by overlapping the spot position of the previous image exposure and the spot position of the subsequent image exposure, a yellow color is formed on the electrostatic image forming member. , magenta, cyan, and black in this order.

Next, the method described in Japanese Unexamined Patent Publication No. 57-111572 will be explained. FIG. 5 is a block diagram of an apparatus according to this method. In FIG. 5, 31 is an electrostatic image forming member, 32 is a transfer roll, 33 to 36 are developing means, and 37 is an image receptor. The method described in Japanese Patent Application Laid-Open No. 57-111572 is not a method of polymerizing a plurality of color toners on the electrostatic image forming member described above, but the method of winding the image receptor 37 around the transfer roll 32 and applying Each time the electrostatic image forming member 31 is subjected to cyan, magenta, yellow, and black development by the 36 developing means, the toner image formed on the electrostatic image forming member 31 is wound around the transfer roll 32 on the image receptor. 37, and polymerized a plurality of color toners on the image receptor 37.Problems to be Solved by the InventionHowever, as the image quality and resolution of color images have improved in recent years, It is desired to reliably match the spot position of the previous image exposure with the spot position of the subsequent image exposure. It is difficult to reliably align the positions of the exposure spots, which causes the spots to be misaligned, resulting in color misalignment of the toner image.

The present invention solves the above problems in terms of red and green.

For the formation of winter bodies with secondary colors of blue and blank,
An object of the present invention is to provide a color image forming method that does not cause color shift.

Means for Solving the Problems In order to solve the above problems, the color image forming method of the present invention converts original image signals into yellow and magenta.

The electrostatic latent image is divided into seven color signals of cyan, red 5, green, blue, and black, and the cycle of creating and developing an electrostatic latent image is repeated multiple times on the surface of the electrostatic image forming member. A color image forming method in which at least yellow, magenta, and cyan colored charged particles are superimposed on the electrostatic imaging member, and the red, green, blue, and blank winter bodies are superimposed on the electrostatic imaging member. When formed, yellow has an inverse polarity with the surface charge of the electrostatic member.

By simultaneously developing two or more of the colored charged particles of magenta and cyan, one of the colors of red, green, blue, and black is developed once for each rotation of the electrostatic image forming member. This is a method characterized by forming an image on the image and repeating this process to form all the images.

Function: By the method of the present invention in which two or more colored charged particles of yellow, magenta, and cyan are simultaneously developed in one electrostatic latent image formation, two colors of red, green, blue, and blank are developed.
The formation of images of each of the secondary colors and higher colors does not cause color shift, and as a result, the winter bodies of secondary colors and higher of red, green, blue, and black become clear images with high resolution.

EXAMPLE An example of the color image forming method of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of a first embodiment of the present invention. In FIG. 1, l is an electrostatic image forming member such as arsenic selenium, selenium tellurium 5 amorphous silicon, or an organic photoconductor, 2 is a charger such as a corotron or scorotron, and 3 is a light emitting diode array, a semiconductor laser, or a liquid crystal optical shutter. Exposure means such as arrays and ordinary lamps, 4.5 and 6.7 are yellow (Y) and magenta (
M), cyan (C), and black (Black) toner are contained separately in the developing means, and 8 is the old one.

Image receptor such as OHP, 9 is a corona charger for transfer, 10
11 is an AC static eliminator for paper peeling, 11 is a static eliminator, and 12 is a cleaning means such as a cleaning blade.

The developing means used in the present invention is a non-contact type developing means in which the developer does not come into contact with the photoreceptor. There is an electric field flying development method in which toner is caused to fly by applying a voltage.

Among the above-mentioned electric field flying development, DC electric field flying in which the voltage applied between the toner carrier and the photoreceptor is a DC voltage is particularly advantageous because - the developed toner becomes difficult to fly back from the photoreceptor to the toner carrier. This is suitable because the developing means will not be contaminated with different types of toner. , magenta, cyan, and black.

Further, the toner used in the present invention is a non-magnetic l-component toner with negative polarity, and the charging polarity of the electrostatic image forming member 1 is charged to at least either positive or negative polarity in the present invention. Although any material can be used, a positively charged organic photoreceptor was used in this example.

FIG. 3 is an operational flowchart of the present invention.

The present invention will be explained in detail using FIG.

First, convert the original image signal into yellow (Y) and magenta (M).
, cyan (C), red (R), green (G).

It is divided into seven signals: blue (B) and black. Y by the signal divided into 7 parts.

Images are formed in the order of M, C, R, G, B, and Black.

First, it is determined whether or not there is a yellow signal among the seven signals divided by 0 to explain the formation of a yellow image. If there is a signal, the two chargers positively charge the electrostatic image forming member 1, and the exposure means 3 forms a yellow electrostatic latent image. A yellow image is formed on the yellow electrostatic latent image using the developing means 4. Finally, the charge of the yellow toner on the electrostatic image forming member 1 and the electrostatic image forming member 1 is removed by a static eliminator 11. If there is no signal, the process moves on to the next magenta process. The magenta image forming process is the same as the yellow image forming process, and the sixth order cyan image forming process is also similar.

Next, it is determined whether or not there is a red signal among the zero-divided signals, which will be described with reference to FIG. 4 regarding the formation of a red image. If there is a signal, the electrostatic image forming member 1 is charged with the charger 2 (4.2), and a red electrostatic latent image is formed by the exposure means 3 (4.3). First, a yellow image is formed on the electrostatic latent image using the developing means 4. At that time, the development contrast voltage of the red electrostatic latent image decreases slightly due to the adhesion of yellow toner, but
Sufficient contrast voltage is maintained to form the next magenta toner image (4.4). Therefore, using the developing unit No. 5, develop the yellow toner to form magenta toner on the yellow (
4.5) That is, development of a plurality of color toners is performed simultaneously during one cycle of charging, image exposure, and development.

By superimposing magenta on yellow in this way, a red image is expressed. Finally, the charges of the magenta and yellow toners on the electrostatic image forming member 1 and the electrostatic image forming member 1 are removed by the static eliminator 11 (4.6). If there is no signal, the following Let's move on to green processing. The green image formation process is similar to the red image formation process.

The same applies to the next step of forming a blue image.

The final black image formation step is the same as the yellow step described above. Further, black image formation may be performed by superimposing three colors of yellow, magenta, and cyan, such as by superimposing two colors of red, yellow and magenta.

Through the above steps, the toner image formed on the electrostatic image forming member 1 is transferred all at once to the image receptor 8 using the transfer corona charger 9, thereby forming a toner image on the image receptor 8. do.

As described above, according to this embodiment, the original image signal is yellow, magenta, cyan, red, and green.

The signals are divided into seven color signals of blue and black, and cycles of charging, image exposure, development, and charge removal are repeated multiple times on the surface of the electrostatic image forming member, thereby producing a plurality of colors on the electrostatic image forming member. When superimposing charged particles, color shift can be eliminated by simultaneously developing colors of secondary colors or higher, and as a result, a clear image with high resolution can be formed.

Effect of the invention As described above, the present invention converts the original image signal into yellow.

It is divided into seven color signals of magenta, cyan, red, green, blue, and black, and is printed on the surface of the electrostatic image forming member.
A color image forming method in which a cycle of creating and developing an electrostatic latent image is repeated multiple times to superimpose colored charged particles of at least yellow, magenta, and cyan on the electrostatic image forming member, the electrostatic image forming method comprising: Said red, green on the parts.

When forming blue and black winter bodies on the electrostatic image forming member, two or more colored charged particles of yellow, magenta, and cyan having polarities opposite to the surface charge of the electrostatic image forming member are simultaneously developed. By doing this, one rotation of the electrostatic image forming member forms an image of one of the red, green, blue, and black colors at a time, and this process is repeated until all images are formed. By doing this, for example, character images can be formed with high resolution and clear images without color shift.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a first embodiment of the present invention, FIG. 2 is an operation flowchart of a conventional color image forming method,
FIG. 3 is an operation flowchart in the first embodiment of the present invention, FIG. 4 is a process diagram for forming a yellow toner image, and FIG. 5 is a block diagram of a conventional color image forming method. ■... Electrostatic image forming member, 2... Charger, 3... Exposure means, 4-7... Development means, 8... ... Image receptor, 9 ... Corona charger for transfer, lO ... AC static eliminator for peeling, 1
1... Static eliminator, 12... Cleaning means, 13... Fixing device.

Claims (1)

[Claims] The original image signal is divided into seven colors: yellow, magenta, cyan, red, green, blue, and black, and the cycle of creating and developing an electrostatic latent image is repeated multiple times on the surface of the electrostatic image forming member. , a color image forming method in which at least yellow, magenta, and cyan colored charged particles are superimposed on the electrostatic image forming member, wherein each of the red, green, blue, and black images is superimposed on the electrostatic image forming member. When forming on the electrostatic image forming member, the electrostatic charge is The image forming member is characterized in that when the image forming member rotates once, an image of one of the red, green, blue, and black colors is formed at a time, and this is repeated to form all the images. Color imaging method.