JPS62184482A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent a non-image area of a photosensitive body from toner sticking by varying the uniform exposure range of a specific light beam and regulating the range of the photosensitive body to which toner can be sticked. CONSTITUTION:A primary latent image which is not functioned as an electrostatic latent image to be developed in formed on the photosensitive body by an electrostatic charger 61 in accordance with the incidence of image exposing light I, uniform blue light beams are made incident upon the latent image forming surface by an exposing device 7B and an electrostatic image generated from the formed primary latent image on the surface of a B filter part of the photosensitive body 4 is developed by a developing device 8Y to form a yellow toner image. The potential of the image forming surface is smoothed by a charger 9Y, green color light beams are uniformly made incident upon the smoothed surface by an exposing device 7G and the potential pattern on the surface of a G filter part is turned to a Magenta toner image by a developing device 8M. Then, red light beams are uniformly made incident by a charger 9M and an exposing device 7R and a cyanine toner image is formed on an R filter part by a developing device 8C. Consequently, a synthesized color image consisting of yellow, Magent and cyanine toner images is formed on the photosensitive body 4.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for forming a primary latent image by charging and imagewise exposing a photoreceptor having an insulating surface layer and a distribution layer of color separation functional elements.
This invention relates to an improvement in an apparatus that forms a color image on an insulating surface layer of a photoreceptor by repeatedly uniformly exposing a specific light to extract a color-separated electrostatic image from a primary latent image and developing the electrostatic image with a specific color toner. In particular, the present invention relates to an improvement that prevents toner from adhering outside the image forming area (hereinafter referred to as non-image area) of a photoreceptor.

[Background of the invention]

The present inventors have previously completed various inventions regarding image forming apparatuses using photoreceptors having the above-mentioned color separation function (Japanese Patent Application Nos. 59-185440 and 59-1870).
No. 44).

Even in an image forming apparatus using a photoreceptor having such a color separation function, as in an image forming apparatus using a photoreceptor without a color separation function, toner may adhere to the non-image area of the photoreceptor. For example, if the image exposure is performed using a scanning exposure device that scans with an optical system or a scanning exposure device that moves the document table, the image exposure pump is turned off and the image exposure pump moves back. The surface of the photoconductor corresponding to the surface of the photoconductor, the area other than the document placement frame, or the area other than the document area when copying without a platen cover is at a black image potential, and the toner adhering to it is cleaned. This increases the load on the device, wastes toner, and contaminates the device and recording paper. In the case of an image forming apparatus that performs variable-magnification copying, the surface of the photoreceptor outside the platen range has a black image potential during reduced copying, and toner adhering there causes a similar problem. In order to eliminate such problems, means are particularly employed to prevent toner from adhering to non-image areas of the photoreceptor.

In an image forming apparatus using a photoreceptor without a color separation function, as a means to prevent toner from adhering to non-image areas, a device is installed between the charger and the image exposure position or between the image exposure position and the developing device. A method that is mainly adopted is to provide an exposure device that exposes a non-image area to eliminate static electricity. This exposure device consists of an array of light emitting diodes LED, liquid crystal LC3, or electroluminium 2.7 sense lamps EL,
A method using a xenon lamp, a combination of a lamp and a lens or a shutter, etc., and a method of changing the developing bias of the developing device are also adopted or used in combination. However, these methods are applicable to those that form electrostatic images using the Carlson method, and cannot be directly applied to those that form electrostatic images using the NP method that uses a photoreceptor with an insulating layer. do not have. From this, in the case of a photoreceptor that has a transparent insulating layer on its surface and forms an e-electronic image using the NP method, it is necessary to There are many methods of uniformly exposing white light using a uniform exposure device that can limit the exposure area.

In contrast to the above, in an image forming apparatus using a photoreceptor having a color separation function, the method of exposing the non-image area to light does not remove static electricity due to the presence of an insulating surface layer, which warps and promotes toner adhesion. , cannot be adopted. The method of changing the developing bias cannot control the developing width in the direction perpendicular to the direction of movement of the photoreceptor, and therefore has the problem of not being able to sufficiently prevent toner from adhering to non-image areas. Furthermore, the NP type uniform exposure apparatus cannot be used because it extracts all the color separation electrostatic images from the primary latent image.

[Purpose of the invention]

The present invention has been made based on the above background,
In an image forming apparatus using a photoreceptor having a color separation function, the exposure area is limited by interlocking a plurality of uniform exposure devices for each specific light that draw color separation electrostatic images from the primary latent image. This was made based on the discovery that by using a toner with a color image, it is possible to prevent toner from adhering to a non-image area without hindering the formation of a color image.

That is, the present invention is an apparatus that can form a color image on a photoreceptor without color shift using a photoreceptor having a color separation function, and is designed to prevent toner from adhering to a non-image area of the photoreceptor. The purpose of the present invention is to provide an image forming apparatus with

[Structure of the invention]

In the present invention, a photoreceptor having an insulating surface layer and a distribution layer of color separation function elements is charged and imagewise exposed to form a primary latent image that is not developed, and then an electrostatic image with a color separation function is extracted from the primary latent image. In an apparatus that forms a color image on the insulating surface layer by repeatedly uniformly exposing the electrostatic image to a specific light and developing the electrostatic image with a specific color toner, the uniform exposure range of the specific light is made variable; The image forming apparatus is characterized in that the range to which toner can adhere to the photoreceptor is regulated by a different exposure range, and this configuration achieves the purpose of entrustment.

〔Example〕

The present invention will be explained below using illustrated examples.

1 to 4 are schematic partial cross-sectional views showing examples of the layer structure of a photoreceptor used in the image forming apparatus of the present invention, and FIGS. 5 and 6 are filters of color separation filter layers of the photoreceptor, respectively. FIG. 7 is a partial plan view showing an example of the distribution shape, FIG. 7 is a schematic configuration diagram showing an example of the image forming apparatus of the present invention, FIG. 8 is a graph showing changes in photoreceptor surface potential in the color image forming process, and FIG. FIG. 10 is a configuration diagram showing an example of a specific light uniform exposure device used in the image forming apparatus of the present invention, and FIG. 10 is a developed plan view showing a charged area of a photoreceptor.

In FIGS. 1 to 4, 1 is a conductive member formed into an appropriate shape as required, such as a cylindrical shape or an endless belt shape, and 2 is a photoconductive member made of an inorganic photoconductor or a leading conductor. layer,
3 consists of a distribution of minute color separation filters for red (R), green (G), blue (B), etc. formed from various polymers, resins, etc. and colorants such as dyes and pigments, that is, color separation functional elements. This is an insulating layer including layer 3a. The insulating layer 3 of the photoreceptor 4 in FIG. 1 is formed by depositing colored insulating materials such as resin on the photoconductive layer 2 in a predetermined pattern by means of printing, photoresist, vapor deposition, etc.; The insulating layer 3 of the photoconductor 4 in FIG. 2 has a transparent insulating layer under the insulating layer 3 in FIG. 1, and the insulating layer 3 of the photoconductor 4 in FIG. The insulation N3 of the photoreceptor 4 in section 4, which further has a transparent insulating layer on top of the layer 3, is similar to the one having a transparent insulating layer on top of the insulating layer 3 in FIG.

R and G in the color separation layer 3a of these insulating layers 3.

The distribution shape of the B filter etc. is not particularly limited, but the fifth
A mosaic distribution as shown in the figure and FIG. 6 is used because it is suitable for reproducing delicate multicolor images.

Regarding the individual sizes of the R, G, B filters, etc., a length range of 10 to 200 μm, as shown by l in the figure, is used from the viewpoint of ease of forming a distribution pattern, image resolution, and color reproducibility. .

The image forming apparatus shown in FIG. 7 includes an image exposure device 6 including a charger 5 and a charger 61 around a drum-shaped photoreceptor 4 having an insulating surface layer 3 and a color separation N3a as described above. Uniform exposure devices 7B and 7G for specific light as shown in FIG.
, 7R, 7, -component or two-component developer is applied to the photoreceptor 4.
Developing devices 8Y and 8M perform non-contact development in which the layer is formed to a thickness that does not contact the surface of the developer layer, and an AC bias is used as a developing bias to cause toner to fly from the developer layer.

8C, 8K, a charger for smoothing the surface potential of the photoreceptor 4 after development; 9Y, 9M, 9C1; an exposure lamp for white light or infrared light that can pass through even a single layer of toner; and a corona discharger. A transfer pre-processing device 10, a transfer device 11. A separator 12, a pre-cleaning static eliminator 13, and a cleaning device 14 are provided to form a color image or a monochrome image on the photoreceptor 4 through the steps described below.

The photoreceptor 4 rotates in the direction of the arrow, and the charger 5 performs corona discharge to uniformly charge the surface of the photoreceptor 4.

When the photoreceptor 4 uses an n-type semiconductor such as cadmium sulfide for the photoconductive layer 2, the corona discharge of the charger 5 is a positive discharge; If it is, it is a negative discharge. As a result, image exposure I is incident on the surface of the charged photoreceptor 4 by the image exposure device 6 . This image exposure device scans and exposes the document ○, regardless of whether the optical system or the document table moves back and forth.
Alternatively, a method may be adopted in which the document O passes through a platen. When the image exposure I is incident, the charger 61 performs corona discharge of alternating current or direct current having a polarity opposite to that of the charger 5. As a result, a primary latent image is formed on the photoreceptor 4, which does not function as an electrostatic image to be developed.

A uniform exposure device 7B uniformly applies blue light to this primary latent image forming surface. Due to this uniform exposure to the blue light, a potential pattern is generated on the surface of the filter portion of the photoreceptor 40B from the previously formed primary latent image. This potential pattern, that is, the electrostatic image is developed with a developing device 8Y containing yellow toner.
A yellow toner image consisting of yellow toner adhered to the surface of the B filter portion is formed. The potential of the surface on which the yellow toner image is formed is smoothed by the charger 9Y, and green light is uniformly incident on the smoothed surface by the uniform exposure device 7G. As a result, a potential pattern is generated on the surface of the G filter portion of the photoreceptor 4, and this potential pattern is developed with a developing bag TL8M containing magenta toner, resulting in a magenta toner image made of magenta toner adhered to the surface of the G filter portion. form. The potential of the surface on which this magenta toner image has been formed is smoothed by the charger 9M, and red light is uniformly incident on the smoothed surface by the uniform n-light device 177R.
Since a potential pattern resides on the surface of the filter portion, the potential pattern is developed with a developing bag H8C containing cyan toner to form a cyan toner image consisting of cyan toner adhered to the R filter portion. 4
Yellow on top.

A color image consisting of a combination of magenta and cyan toner images is formed without color shift. In addition, when the density of this color image, especially the black density, is to be increased, the potential of the surface on which the cyan toner image is formed is further smoothed by the charger 9C, and white light or infrared light is uniformly applied to the smoothed surface. When the light is uniformly incident on the exposure device N7K, this time it hits the photoreceptor 4.
B,G.

A slight potential pattern is generated on the surface of the R filter portion that compensates for the black portion of the original image, so this potential pattern is developed in the developing device 8 containing black toner to remove the black that adhered to the B, G, and R filter portions. A black toner image made of toner is formed. As a result, a color image with a dull image density is formed on the photoreceptor 4 by combining yellow, magenta, cyan, and black toner images. Both the previous three-color image and this four-color image are formed within one rotation of the photoreceptor 4.

In addition, when obtaining a monochromatic image, a potential pattern is formed on the specific light filter part or the entire filter part by front exposure of specific light or front n light of white light or infrared light.
By developing this with an arbitrary developing device, an arbitrary monochrome image can be obtained.

In the above image forming process, the surface potential of the photoreceptor 4 changes as shown in FIG. FIG. 8 shows an example in which the photoconductor FJ2 of the photoreceptor 4 is made of p-type semiconductor Se-Te, and shows changes in the surface potential of the photoreceptor 4 in each step up to three-color image formation. .

In FIG. 8, from time t0 on the horizontal axis to 1. -order charging from t1 to 1.0 indicates a state in which the surface of the photoreceptor 4 receives corona discharge and is charged while passing through the charger 5, and is charged from tl to 1. The dark decay until the surface passes through the charger 5 and reaches the charger 61 indicates a state in which the charged potential changes due to charge injection and dissipation of the injected charge. Also from time t2 to t
Secondary charging up to 3 shows a state in which the surface that has reached the charger 61 receives corona discharge and image exposure I while passing through the charger 61, and the potential changes, and the curves ■ and ■ in this period are , respectively, show potential changes in the areas where the bright and dark areas of image exposure (1) are incident. Due to this secondary charging, the potential of the surface of the photoreceptor 4 is substantially smoothed, and there is no potential pattern to which toner adheres. Even after time t, there is a portion where the potential contrast decreases due to dark decay, but this is omitted in FIG. From time t, to t.

Uniform exposure at the same time indicates a state in which the surface that has passed through the charger 61 is uniformly exposed to blue light and the potential changes while passing through the position of the uniform exposure device 7B. Due to this uniform exposure, the dark area potential V changes to a potential at which toner adheres during development, but the bright area potential VL hardly changes from the potential at which toner does not adhere. It goes without saying that the intermediate gradation area takes a potential intermediate between the bright area potential vL and the dark area potential V. As a result, when the uniformly exposed surface passes through the developing device 8Y by 1 ffl from time t4 to time t and is subjected to a developing action, a yellow toner image is formed. However, if the uniform exposure device 7B did not perform uniform exposure, the surface potential of the photoreceptor 4 would not change from the state at the end of secondary charging and would be subjected to a developing action by the constant value imager 8Y. Toner will not stick to the paper even if you use it. Taking advantage of this, the image forming apparatus of the present invention prevents toner from adhering to the non-image area of the photoreceptor 4. In other words, uniform exposure system? u
By using a uniform exposure device 7 capable of changing the uniform exposure range as shown in FIG. To maintain the non-image area in a state where secondary charging has been completed and to prevent toner from adhering to the non-image area.

The uniform exposure device 7 in FIG. 9 has LEDs, ELs, or LCs 3 divided into many parts arranged on a substrate 70 in the width direction of the photoreceptor 4, and always arranged in groups corresponding to the beams included in the image forming area. 71 and a group 72 corresponding to the width that enters the image forming area or becomes a non-image area due to scaling etc.
When the width of the image forming area becomes narrow due to reduction copying, etc., the groups 71 and 72 are set to emit light together by a switch 73, and the direction of rotation of the photoreceptor 4 is determined by the switch 74, which turns on each LED, EL, or LC3. The uniform exposure area is controlled by changing the time.

Although FIG. 9 shows only two groups, it goes without saying that it can be divided into more groups if necessary.

By reducing the size of each group, the image forming area can be finely restricted. Furthermore, by adding a lens to each LED to give directionality to the emitted light flux, not only can the image forming area and non-image area be clearly defined, but also the light that has passed through a specific filter can be directed to other filter areas. It is possible to prevent the occurrence of problems such as light entering the IT layer and deteriorating color reproducibility.

L E D4) E L or LC3 emits or emits blue light in the uniform exposure device 7B, and emits green light in the other uniform exposure devices 7G, 7R, and 7K, respectively. Of course, it is also a device that emits or projects red light, white light, or infrared light. Part 75 in Figure 9
B is provided with an additional lens, LED, EL, or LC3 as described above as necessary to project specific light.

G, R, etc. filters are shown.

As a result of the uniform exposure between time t and t4 in FIG. 8 being performed by the uniform exposure device ff7B as described above, time t4
During development using the developing bag ff18Y' between 0 and t, the yellow toner adheres only to the area where the uniform exposure of blue light is incident.

The recharging between is the developing device! While the surface of the photoreceptor 4 on which the yellow toner image is formed in 8Y passes through the charger 9Y, the surface potential changes due to corona discharge and changes to the same level as the bright region potential vL to which toner does not adhere. The uniform exposure between time 0 t6 and time t is performed using the uniform exposure device ff7G.
uniform exposure, and the uniform exposure system ff17G is also -pJ
Since only the image forming area is uniformly exposed like the n optical system ff7B, the next time t.

During the development using the developing bag flf8M from to t8, the magenta toner adheres only to the area where the uniform exposure of the green light is incident, and does not adhere to the non-image area. Recharging from time ta to t9 indicates a state in which the surface developed by magenta toner passes through the charger 9M and the potential is smoothed, and from time t to t
l. The uniform exposure between them indicates a state in which an electrostatic image is formed by further uniform exposure of red light by the uniform exposure device 7R. Since this uniform exposure is also performed only in the image forming area w4, the time t. Even during development by the developing device 8C between tl+ and tl+, cyan toner does not adhere to the non-image area.

With the above steps, the photoreceptor 4 can be removed without any toner being attached to the non-image area.
A three-color pattern is formed in the image forming area.

When forming a four-color image, recharging is performed by the charger 9C, uniform exposure is performed by the uniform exposure device 7K, and development is performed by the developing device 8K, and in this case as well, toner adheres to the non-image area. Never.

The color image or monochrome image formed as described above is easily transferred by the transfer pre-processing device 10, and the paper feed device 1
The image is transferred by the transfer device 11 onto the recording paper P fed by the printer 5. The recording paper P onto which the toner image has been transferred is transferred to a separator 1.
2, the toner is separated from the photoreceptor 4, transported to the fixing bag T117 by the conveying means 16, the toner is fixed by the fixing device 17, and the toner is discharged outside the machine. On the other hand, the surface of the photoreceptor 4 to which the toner has been transferred is neutralized by a pre-cleaning static eliminator 13, and then residual toner is removed by a cleaning device 14, and the photoreceptor 4 is subjected to the next image forming process.

The present invention is characterized in that the image forming area is exposed to each specific light without exposing the non-image area to each specific light, and it is possible to specify the potential pattern generation area independently of the image exposure area. It is a characteristic. Therefore, the non-image area is recorded not only by the area of the document or platen cover, or by the surface of the photoconductor corresponding to the image exposure lamp being turned off and returning from scanning movement, but also by changes in the size of the recording paper P. It also includes the surface of the photoreceptor that comes off from the paper P.

That is, based on information from a conventionally known document size detection device and magnification ratio detection device provided in the image exposure device section, recording paper size detection device provided in the paper feeder section, or recording paper size and magnification ratio specification means. , determine the exposure time, exposure timing, and exposure width of each specific light,
It is possible to prevent toner from adhering to the above-mentioned non-image area and to form an image only in the necessary image forming area. It goes without saying that each uniform exposure device operates at the same timing so as to correspond to the same image forming area. For example, to obtain a reduced image, the projected image area is reduced. The user specifies the recording paper size and variable magnification (F6 small magnification). This information allows the program to:
The exposure timing and intensity are determined so that only the area corresponding to the recording paper size is irradiated with the specific light. Furthermore, if the user specifically specifies the original size, the smaller one is selected compared to the reduced projected original size and the exposure area corresponding to the paper size. The same applies when obtaining an enlarged image.

When obtaining a normal 1:1 image at the same size, it is preferable to automatically give priority to the recording paper size. Also,
If the document is made of thick wood or the like, the document portion may be regarded as a black image due to lifting from the document table, and the edges of the resulting image may become black. In that case, it is preferable to make the uniform exposure area 1 to 5 mm narrower than the recording paper size. Such frame erasing means is also performed automatically or by designated means.

The image forming apparatus of the present invention is not limited to the example shown in FIG. 7, but is capable of printing other than yellow, magenta, and cyan, for example, blue.

It goes without saying that it may be one that forms a color image using green and red toners, and is not limited to one that has four sets of developing devices and the like. Further, in the image forming process described above, by performing uniform exposure using only one of the uniform exposure devices 7B, 7G, 7R, and 7 and disabling the others, one color can be formed on the photoreceptor 4. A monochromatic image consisting of a toner image is formed, but the monochromatic image is inferior in image density and resolution to those formed by a monochromatic copying machine, except for those using black toner. Therefore, the monochrome image outside the blackboard has the same image density as on a monochrome copying machine.

Uniform exposure devices 7B and IG are provided with uniform exposure devices similar to uniform exposure device WIK so as to be able to form images with high resolution.

It may also be provided adjacent to each of the 7Rs.

When forming a monochrome image, uniform exposure device 7B
, 7G, and 7R, uniform exposure may be performed using the uniform exposure apparatus. In this case, the surface potential developed by uniform exposure can be further developed in a subsequent developing device without smoothing, thereby forming, for example, a red image consisting of yellow toner and magenta toner.

Further, the present invention is disclosed in Japanese Patent Application No. 60-22 as an image forming method.
The present invention can be similarly applied to an image forming apparatus that repeats primary charging, secondary charging, after image exposure, charging for smoothing, whole surface exposure with specific light, and development as described in No. 9524. Further, the photoreceptor has a filter provided on the side of the mN substrate with respect to the photoconductive layer, and image exposure and full-scale exposure are performed from the filter side (Japanese Patent Application No. 59-199547
No.) and other configurations (Patent Application No. 1981-1981, 1
98167, 201084). Furthermore, the photoconductive layer is not limited to a single layer, but also has a functionally separated structure consisting of a charge generation layer and a charge transfer layer (patent application
No. 0-245178). Alternatively, the photoreceptor may have a structure in which the photoconductive layer has a color separation function (Japanese Patent Application Nos. 59-201085 and 60-245177).

Hereinafter, the present invention will be further explained using more specific examples.

A photoreceptor 4 having a color separation function and made of polyethylene terephthalate having a thickness of 20 μm was used in an image forming apparatus capable of variable magnification copying as shown in FIG. Using this image forming apparatus, images were formed on an A4 original size, an 85 recording paper size, and a reduction rate of 86% by the process described with reference to FIG.

First, the photoreceptor 4 is uniformly negatively charged by the charger 5. Next, while being subjected to image exposure I, it is charged with a reverse polarity by a charger 61 so that the surface potential becomes approximately 0. It is preferable that the charging width by the charger 5 is narrower than that by the charger 61.

In order to form a complete image in the image forming apparatus of the present invention, (i) Charge width by charger 5≦Charge width by charger 61 (ii) Charge width by charger 5.61≧Image exposure width (i) ( The relationship between the primary latent image width formed by ii) and the uniform exposure width is (iii) primary latent image width≧−uniform exposure width. In the case of (iii), it is ideal to have an equal sign when copying the entire original size, but it is necessary to narrow the uniform exposure width to some extent.

The size of the A4 version is 210 x 297 sx.

The size of the 85th edition is 1B2 x 2571111.

An A4 size original is reduced to 85 size by an optical system and image exposed. On the other hand, the length of the charging area in the direction of rotation of the photoreceptor 40 is, for example, 85 plate size 1B2 x 257 v
A-182U can be controlled by turning on and off the power supply that supplies power to the charger, but the photoreceptor 4
The length in the width direction is the charging width corresponding to the length of the charger. Therefore, even if the charged area is controlled, image-exposed and unirradiated areas as shown in FIG. 10 will occur. When uniform exposure is applied to this image-unexposed area, the toner adheres in a solid manner.

To prevent this, the image exposure jff M overlaps with 180
A uniform exposure was applied to an area of the X255 tuna.

If the uniform exposure devices 7B to 7K cannot irradiate uniform exposure to the same width as the image exposure width due to the size of the EL, LED, or LC8, the number of groups to be lit is reduced by one for the EL, LED, or LC3, and the irradiation width is narrow. Depending on the thickness of the original, a black frame may be formed even if uniform exposure is applied to the same area as the image exposure area, but it is effective to narrow the uniform exposure area to prevent this. . Uniform exposure device 7B, 7G
, 7R.

All uniform exposure areas formed by 7K must be identical.

The width direction length of the photoreceptor 4 cannot be adjusted unless the length of the charger is changed in the charged area by the chargers 9Y, 9M, and 9C after development. It can be controlled by turning the power on and off.

Regardless of the charging width before the primary latent image is formed, the charger 9Y.

Even if the charging width is set by 9M or 9C, it will not appear as a potential pattern because the exposure device is controlled uniformly even if the charging width is slightly different, but it is better to control the charging width according to the size of the recording paper to increase exposure. This is preferable because it can reduce fatigue of the body 4.

As described above, it was possible to obtain copying recording paper with high image quality and no black borders by the simple means of uniform exposure control.

〔Effect of the invention〕

By using a photoreceptor having a color separation layer, the image forming apparatus of the present invention can form a color image without color shift, and can make the image forming area of the photoreceptor variable by using a uniform exposure device for specific light. By making it possible to expose only the non-II! Toner is prevented from adhering to the IIA area, the burden on a cleaning device and the amount of toner consumed are reduced, and contamination by toner is reduced. In particular, it is possible to simplify the drive control of chargers, developing devices, etc., and furthermore, it is possible to control these at the same timing, and it is possible to use devices with simple structures for them. be effective.

[Brief explanation of drawings]

1 to 4 are partial plan views showing examples of the filter distribution shape of the color separation filter layer of the image forming bag of the present invention, respectively;
FIG. 7 is a schematic configuration diagram showing an example of the image forming apparatus of the present invention;
80 is a graph showing changes in the surface potential of the photoreceptor in the color image forming process, FIG. 9 is a schematic configuration diagram showing an example of a specific light uniform exposure device used in the image forming apparatus of the present invention, and FIG. FIG. 4 is a developed plan view showing the charged V4 region of the body. 1... Exclusive electrical member, 2... Photoconductive layer, 3...
- Insulating layer, 3a... Color separation layer, 4...
Photoreceptor, 5... Charger, 6... Image exposure device, 7B, 7G, 7R, 7, 7... Uniform exposure device, BY
, 8M, 8C, 8K...Developing device, 61.9Y, 9M
, 9C... Charger, 10... Transfer pre-processing device, 11
...Transfer device, 12...Separator, 13...Pre-cleaning static eliminator, 14...Cleaning device. Patent applicant Konishiroku Photo Industry Co., Ltd. Figure 1 Figure 2 Figure s 3 Figure 4 Figure 9

Claims (2)

[Claims] (1) After a photoreceptor having an insulating surface layer and a distribution layer of color separation functional elements is charged and imagewise exposed to form an undeveloped primary latent image, a specific light is used to draw out a color separation electrostatic image from the primary latent image. In an apparatus that forms a color image on the insulating surface layer by repeatedly performing uniform exposure and developing the electrostatic image with a specific color toner, the uniform exposure range of the specific light is made variable; An image forming apparatus characterized in that a range to which toner can adhere to a photoreceptor is regulated. (2) The image forming apparatus according to claim 1, wherein the uniform exposure range of the specific light is changed according to the recording paper size.