JPH07325449A - Color image forming device - Google Patents

Abstract

PURPOSE:To prevent light projected from an image exposure means inside an image forming body from being transmitted, after the exposure of the photosensitive body of the image forming body, and reflected inside a device, resulting in re-exposure of the photosensitive layer. CONSTITUTION:A plate-like light absorbing member 100 which has a black, glossless surface facing a drum and is long in the direction of the shaft of the drum is disposed in the position facing the periphery of the drum, opposite the exposing position of each exposure optical system 12 incorporated in the photosensitive drum 10. After a latent image is formed on the photosensitive layer of the drum by the use of light projected from each exposure optical system 12 at the time of image exposure on the photosensitive drum 10, the transmitted light is absorbed by the light absorbing member 100.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic system in which a plurality of image exposing means and developing means are arranged on the peripheral surface of an image forming body so that toner images are superposed during one rotation of the image forming body. The present invention relates to a color image forming apparatus.

[0002]

2. Description of the Related Art As a method for forming a multicolor image, a monochromatic toner image formed on each of the photoconductors is transferred by using a photoconductor, a charging device, a developing device and the like as many images as necessary. A device (A) that creates a color image by superimposing it on
A device (B) for forming a color image by repeating charging, image exposure and development for each color by rotating one photosensitive member a plurality of times, or similarly, charging, image exposure for each color and image exposure within one rotation of one photosensitive member. An apparatus (C) or the like is known in which development is sequentially performed to form a color image.

However, the above-mentioned device (A) has a drawback in that the volume of the device becomes large because it requires the conveyance of a plurality of photoconductors or transfer members, while the device (B) has a charging means, an image exposing means and a photoconductor. Since there is only one, the volume is reduced, but the size of the image formed is limited to the surface area of the photoreceptor or less.

Although the apparatus (C) is capable of high-speed image formation, it is necessary to dispose a plurality of sets of a charger, an image exposure means and a developing device within one circumference of the photosensitive member, and an optical system for image exposure. There is a possibility that the toner leaking from the developing device close to the system may stain the image quality and impair the image quality.To avoid this, the distance between the image exposing means and the developing device needs to be increased, so the diameter of the photoconductor inevitably increases. There is a contradiction that the device will become larger.

For the purpose of avoiding the drawbacks of the above-mentioned obstacles in the apparatus (C), the substrate of the image forming body is made of a transparent material, and a plurality of image exposing means are housed therein to form an image. An apparatus has been proposed in which the photosensitive layer formed on the outer periphery of the substrate is exposed through the substrate (for example, JP-A-5-307307).

[0006]

However, in an apparatus in which an image exposing means is included in an image forming body, the exposure transmitted through the photosensitive layer is radiated into the inside of the apparatus and the photosensitive layer is re-exposed by reflected light. However, it is inevitable to change the latent image formed by exposure.

Further, when the image forming body already carries a toner image and is subjected to image exposure in superposition, a part of the toner of the toner image at the position where the image forming body is discharged by exposure is in a floating state. There is also a risk of scattering.

On the other hand, the image forming body removes the residual charge by exposure before charging the photosensitive layer, at the time of transferring the toner image, and before cleaning the residual toner after the transfer, thereby applying a uniform electric potential and transferring the transfer rate. In addition, the process of pre-exposure that facilitates cleaning of residual toner is incorporated, but even in the case of such exposure, useless reflected light causes a change in the latent image formed as in the case of the image exposure described above. Or, the toner may be scattered in the apparatus.

As a result of solving these problems and improving the present invention, as a result, it is possible to efficiently prevent re-exposure of the photosensitive layer and scattering of toner due to each of exposure before image exposure and charging, simultaneous transfer and cleaning, and high quality. It is an object of the present invention to provide a color image forming apparatus capable of forming an image.

[0010]

SUMMARY OF THE INVENTION The above-mentioned object is a color in which a toner image is formed on an image forming body by repeating charging, image exposure and development on the image forming body, and then collectively transferring to a transfer material. In the image forming apparatus, the image forming body includes a plurality of image exposing means, and a light absorbing member is provided outside an exposure position of the image forming body facing the image exposing means. An apparatus (first invention), and a color image forming apparatus that performs charging, image exposure, and development on an image forming body to form a toner image on the image forming body in a superimposed manner, and then collectively transfers the toner images to a transfer material. The image forming body includes a plurality of image exposing means, and an electrode member to which a voltage having the same polarity as that of the toner is applied is provided outside the exposure position of the image forming body facing the image exposing means. Color image formation (2nd invention), and a color image forming apparatus that performs charging, image exposure, and development on an image forming body to form toner images on the image forming body in a superimposed manner, and then collectively transfers the toner images to a transfer material. The image forming body includes a plurality of image exposing means, and the exposure position of the image exposing means is in a developing container upstream of the developing sleeve of the developing means (third invention). ), And a color image forming apparatus for forming a toner image on the image forming body by repeatedly charging, exposing and developing the image forming body, and then collectively transferring the toner image onto a transfer material. Includes a plurality of image exposing means and pre-charging exposing means, and the exposure position of the pre-charging exposing means is in the cleaning container on the upstream side of the charging means and on the downstream side of the cleaning means. An image forming apparatus (fourth invention) and a color image formation in which a toner image is superposedly formed on the image forming body by repeating charging, image exposure and development on the image forming body, and then collectively transferring to a transfer material. In the apparatus, the image forming body includes a plurality of image exposing means and pre-cleaning exposing means, and the exposure position of the pre-cleaning exposing means is in a cleaning container on the upstream side of the cleaning means. (5th aspect of the invention), and a color image forming apparatus for performing batch transfer to a transfer material after forming a toner image on the image forming body by repeating charging, image exposure and development on the image forming body, The image forming body includes a plurality of image exposure means and transfer simultaneous exposure means, and the exposure position of the transfer simultaneous exposure means is set to the downstream side of the position closest to the transfer means. And a color image forming apparatus (sixth invention).

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Prior to the description of each embodiment of the present invention, the structure of a color image forming apparatus common to each invention will be described with reference to FIGS.

Reference numeral 10 denotes a drum-shaped image forming body, that is, a photosensitive drum, which is coated with a transparent conductive layer and an organic photosensitive layer (OPC) on the outer periphery of a cylindrical substrate formed of a transparent member such as optical glass or transparent acrylic resin. It was done.

A flange 10A at one end of the photosensitive drum 10 has a guide pin 30 provided in a cartridge 30 described later.
The flange 10B at the other end is supported by P, and the flange 10B at the other end is fitted onto a plurality of guide rollers 40R provided on the substrate 40 of the apparatus main body to mesh the outer gear 10G with the drive gear 40G. Rotated clockwise with the layers grounded.

Reference numeral 11 denotes a scorotron charger, which is a photosensitive drum 10.
The above-mentioned organic photoconductor layer is charged by a grid held at a predetermined potential and corona discharge by a discharge wire to give a uniform potential to the photoconductor drum 10.

Reference numeral 12 denotes FL, EL, PL, L in which light emitting elements arranged in the axial direction of the photosensitive drum 10 are arranged in a line in an array.
LI in which EDs and elements having an optical shutter function are arranged in a line
In an exposure optical system composed of SA, PLZT, LCS and a self-occ lens as a unity magnification image forming element, image signals of respective colors read by a separate image reading device are sequentially taken out from a memory, and each of the above-mentioned each. The signals are input to the exposure optical system 12 as electric signals.

Each of the exposure optical systems 12 is attached to a cylindrical support member 20 which is fixed to a substrate 40 of the apparatus main body with a guide pin 40P1 as a guide, and is mounted on the photosensitive drum 10.
Is housed inside the base body of.

Reference numerals 13Y to 13K denote developing units for accommodating yellow (Y), magenta (M), cyan (C) and K (black) developers, respectively, each having a predetermined gap with respect to the peripheral surface of the photosensitive drum 10. Development sleeve 13 that keeps the same and rotates in the same direction
Equipped with 0.

Each of the developing devices is in a non-contact state by applying a developing bias voltage to the electrostatic latent image formed on the photosensitive drum 10 formed by the charging by the charging device 11 and the image exposure by the exposure optical system 12 described above. Reverse development with.

Next, the process of the color image forming apparatus in this apparatus will be described.

The original image is temporarily read as an image signal for each color of Y, M, C and K from an image read by an image pickup device or an image edited by a computer in an image reading apparatus separate from this apparatus. Stored and stored in memory.

When the photoconductor drive motor is started by the start of image recording, the drive gear 40G is rotated to rotate the photoconductor drum 10 in the clockwise direction, and at the same time, the photoconductor is driven by the charging action of the charger 11 (Y). Application of electric potential to the drum 10 is started.

After the photosensitive drum 10 is applied with a potential,
In the exposure optical system 12 (Y), the exposure by the electric signal corresponding to the first color signal, that is, the yellow (Y) image signal is started, and the yellow (Y) of the original image is formed on the photosensitive layer on the surface by the rotational scanning of the drum. ) Form an electrostatic latent image corresponding to the image.

The latent image is reversal-developed by the developing device 13 (Y) with the developer on the developing sleeve in a non-contact state, and a yellow (Y) toner image is formed according to the rotation of the photosensitive drum 10.

Next, the photoconductor drum 10 is given a potential on the yellow (Y) toner image by the charging action of the charger 11 (M), and the second color signal of the exposure optical system 12 (M), that is, Exposure with an electric signal corresponding to the magenta (M) image signal is performed, and non-contact reversal development by the developing device 13 (M) causes a magenta (M) toner image on the yellow (Y) toner image. Will be sequentially stacked.

By the same process, a cyan (C) toner image corresponding to the third color signal is further generated by the charger 11 (C), the exposure optical system 12 (C) and the developing device 13 (C), and the charger also. 11 (K), exposure optical system 12 (K) and developing unit 13
By (K), a black (K) toner image corresponding to the fourth color signal is sequentially superimposed and formed, and a color toner image is formed on the peripheral surface of the photosensitive drum 10 within one rotation.

Photoreceptor drum 10 by each of these exposure optical systems
The exposure to the organic photosensitive layer is conducted through the transparent substrate from the inside of the drum. Therefore, the exposure of the images corresponding to the second, third and fourth color signals is performed without any influence of the toner image previously formed.
It is possible to form an electrostatic latent image equivalent to the image corresponding to the color signal of. The stabilization of the temperature inside the photosensitive drum 10 and the prevention of the temperature rise due to the heat generation of each exposure optical system 12 use a material having good thermal conductivity for the supporting member 20, and use a heater 201 when the temperature is low, When the temperature is high, it can be suppressed to a level without any trouble by taking measures such as radiating heat to the outside through the heat pipe 202. Further, during the developing action by each developing device, a developing bias in which a direct current or an alternating current is applied to the developing sleeve 10 is applied, and jumping development is performed by the one-component or two-component developer accommodated in the developing device, and the transparent A non-contact reversal development is performed in which a DC bias having the same polarity as that of the toner is applied to the photoconductor drum 10 having the conductive layer grounded so that the toner is attached to the exposed portion.

Thus, the color toner image formed on the peripheral surface of the photosensitive drum 10 is transferred to the transfer paper which is conveyed from the paper feed cassette 15 in the transfer device 14A and is fed synchronously by the driving of the timing roller 16. It

The transfer paper on which the toner image has been transferred is a static eliminator.
In 14B, the charge is removed and the toner is separated from the peripheral surface of the drum. After the toner is fused in the fixing device 17, the toner is discharged via the paper discharge roller 18 onto the tray above the device.

On the other hand, the photosensitive drum 10 from which the transfer paper has been separated removes and cleans the residual toner in the cleaning device 19 to continue the formation of the toner image of the original image, or temporarily stops the toner image of the new original image. Formation.

The photoconductor drum 10, each charging device 11, each developing device 13 and the cleaning device 19 are housed in a cartridge 30 and integrated with each other, without giving a load or a shock to the image exposure means, and an optical system. The supporting member 20 having 12 is left so that it can be attached to and detached from the main body of the apparatus. The heater 201 and the heat pipe 2 have a structure in which the supporting member 20 is left when attaching and detaching.
02. It has a feature that the lead wire 203 for operating the LED and the optical system 12 can be fixed to the support member 20 in spite of the rotation of the photoconductor and the attachment / detachment of the photoconductor. It can also be used to determine the axis of the photosensitive drum 10 as described below.

(Embodiment 1) An embodiment of the first invention will be described with reference to FIG.

Each of the exposure optical systems 12 has a plate-shaped light absorbing member 100 having a predetermined width and a length corresponding to the axial direction of the drum, outside the exposure position of the photoconductor drum 10 facing each other. I have it.

Each of the light absorbing members 100 described above has the exposure optical system 12
Upon image exposure of the photoconductor drum 10 by the above, it is installed at a position where all the transmitted light emitted to the outside of the drum is received.

At least the side of the light absorbing member 100 facing the photosensitive drum 10 absorbs the image exposure light. For example, it has a black matte surface state and efficiently absorbs the transmitted light without reflecting it, thereby preventing re-exposure of the photosensitive layer due to reflection of the transmitted light in the machine.

In principle, the color of the electrode member may absorb the image exposure light, but black is preferred in order to reduce the effects of transfer, cleaning, pre-transfer exposure and light leakage from outside the machine.

The light absorbing member 100 is formed of a conductive material which can also serve as an electrode, and is placed thereon. When image exposure is performed by superimposing it on a toner image, a voltage having the same polarity as that of the toner is applied. Thus, it is possible to prevent the toner from scattering by forming an electric field for pressing the toner toward the image forming body. In this case, the effect can be achieved by making the applied voltage higher than the charging potential of the photoconductor drum 10 by the charger 11 or the DC component voltage of the bias applied to the developing sleeve 130 of the developing device 13.

(Embodiment 2) An embodiment of the second invention will be described with reference to FIG.

Each of the exposure optical systems 12 is provided with a plate-like electrode member 110 having a predetermined width and a length corresponding to the axial direction of the drum, outside the exposure position of the photoconductor drum 10 facing each other. ing.

The electrode member 110 is installed at a position where all the transmitted light emitted to the outside of the drum upon image exposure of the photosensitive drum 10 by the exposure optical system 12 is received.

The electrode member 110 is applied with a voltage E having the same polarity as the toner at the same time as the image exposure by the exposure optical system 12 is projected, so that the toner of the toner image already formed is superposed. It suppresses floating and scattering by projection.

The voltage E is the charging potential of the photoconductor drum 10 by the charger 11 or the developing sleeve 130 of the developing device 13.
The effect is exhibited by making the voltage higher than the DC component voltage of the bias applied to.

If at least the side of the electrode member 110 facing the photoconductor drum 10 is made to have a black glossy surface state, it absorbs the transmitted light passing through the photosensitive layer at the time of image exposure and is exposed by reflection of the transmitted light. It can also serve as a light absorbing member for preventing re-exposure of the layer.

In principle, the color of the electrode member may absorb the image exposure light, but black is preferred in order to reduce the influence of transfer, cleaning, pre-charge exposure and light leakage from outside the machine.

(Embodiment 3) An embodiment of the third invention will be described with reference to FIGS.

Each of the above-mentioned exposure optical systems 12 corresponds to the photosensitive drum 1 on the upstream side of the developing sleeve 130 in the container of each developing device 13.
An exposure position (indicated by an arrow) is set on the peripheral surface of 0.

Since the air flow in the direction shown by the broken line in FIG. 6 is formed in the opening of the container 131 on the upstream side of the sleeve by the rotation operation of the photosensitive drum 10, one of the toner images formed on the drum by image exposure is Even if some toner is floating, the toner is prevented from being sent to the inside of the container 131 and scattered to the outside by the air flow.

Further, the container 131 has an inner wall surface 131A facing the exposure position formed of a black non-glossy light absorbing member, so that the light transmitted through the photosensitive layer for image exposure is absorbed and the inside wall of the container 131 is protected. It can also have a function to prevent the disturbance of the latent image due to reflection.

Further, by forming a voltage E having the same polarity as the toner by forming an electrode member 131B near or on the upstream side of the image exposure portion of the container 131, the toner of the toner image already formed is superposed. It is also possible to suppress floating and scattering by image exposure. The electrode portion 131B can also serve as a black matte light absorbing member.

In this case, since the voltage E is the reversal development, it has the same polarity as that of the toner, and the photosensitive drum 10 by the charger 11 has the same polarity.
The effect can be obtained by setting the charging potential of 1 or the voltage value higher than the bias voltage of the DC component with respect to the developing sleeve 130 of the developing device 13.

(Embodiment 4) An embodiment of the fourth invention will be described with reference to FIG.

The support member 20 further supports an exposure lamp and an LED array used as a light source of the pre-charging exposure means L1. The pre-exposure to the is performed from the inside of the drum.

The pre-charging exposure means L1 includes a photosensitive drum.
A light source with a size equivalent to 10 axial lengths is used,
A blade serving as a cleaning means of the cleaning device 19 has its exposure area formed by the reflecting member 121 having a concave mirror inside.
It is limited to the drum peripheral surface between the pressure contact of 19A and the end surface of the downstream container 19B.

Therefore, the pre-charging exposure means L1 is continuously operated because there is no possibility that the toner scattered by cleaning adheres and the transmitted light passing through the photosensitive layer does not leak to the outside from the cleaning container 19B. It is possible to apply a uniform charge to the photoconductor by the charging action in forming a new image.

By providing a black matte surface state as a light absorbing member on the inner surface of the cleaning container 19B,
It is also prevented that the slight irradiation light reflected in the container leaks to the outside.

(Embodiment 5) An embodiment of the fifth invention will be described with reference to FIG.

The support member 20 is further provided with an exposure lamp or LE used as a light source of the pre-cleaning exposure means L2.
The pre-cleaning exposure for the photoconductor is performed from the inside of the drum by utilizing the fact that the substrate of the photoconductor drum 10 is a transparent body while supporting the D array.

A light source having a size corresponding to the axial length of the photosensitive drum 10 is used as the pre-cleaning exposure means L2, and the exposure area of the cleaning device 19 is defined by the reflecting member 122 having a concave mirror inside. It is limited to the peripheral surface of the drum 19A which is the cleaning means and each pressure contact of the plate-like or roller-like toner collecting member 19C provided upstream thereof.

The residual toner on the photosensitive drum 10 onto which the toner image has been transferred is separated from the drum surface by the blade 19A and drops, and is conveyed to the toner recovery path by the rotation of the toner recovery member 19C and recovered. It

Therefore, the pre-cleaning exposure means L2
Is that there is no possibility that toner scattered due to cleaning will adhere, and that the projection light will cause the blade 19A to
Since the residual charge is effectively eliminated by concentrating on the drum surface on the upstream side of, the residual toner is efficiently removed by the blade 19A.

The pre-cleaning exposure means L2 is
By expanding the exposure area to the end surface of the cleaning container 19B on the downstream side of the blade 19A, it is possible to use it as a light source for both pre-cleaning exposure and pre-charging exposure.

(Embodiment 6) An embodiment of the sixth invention will be described with reference to FIGS. 9 and 10.

The support member 20 further supports an exposure lamp and an LED used as a light source of the transfer simultaneous exposure means L3, and the base of the photoconductor drum 10 is a transparent body so that the support member 20 can be used for the photoconductor. Simultaneous transfer exposure is performed from the inside of the drum.

A light source having a size corresponding to the length of the photosensitive drum 10 in the axial direction is used as the transfer / simultaneous exposure means L3, and the exposure area is defined by the reflecting member 123 having a concave mirror on the inner side thereof. It is limited to be performed uniformly from the peripheral surface of the drum located closest to the corona discharge electrode to the downstream side thereof.

If the exposure is performed before the closest contact, the adhesion of the toner to the image forming body is reduced, and the toner is easily scattered to cause dust in the image.

The exposure area is limited within the range in which the downstream side thereof reaches at least the cleaning device 19 beyond the separation area by the static eliminator 14B described above.

The transfer-simultaneous exposure means L3 has a function of discharging the electric charge of the photoconductor drum 10 carrying the toner image upon transfer of the toner image to the transfer paper by the irradiation thereof, so that the transfer device 14A transfers the toner image. Is performed efficiently and even after transfer, the charge on the photoconductor is efficiently removed by the synergistic action with the static eliminator 14B. Therefore, the transfer paper is separated from the drum surface and the residual toner is removed by the cleaning device 19. Cleaning is also promoted.

Irradiation of the transfer simultaneous exposure means L3 is started after the transfer paper comes into close contact with the image forming body and is charged by the electrodes of the transfer device 14A, so that the disturbance of the toner image on the photosensitive member is avoided and stabilized. The transferred image can be transferred.

On the other hand, in the apparatus using the transfer roller 140A for transferring the toner image as shown in FIG. 10, the exposure area of the exposure lamp L3 is uniform from the peripheral surface of the drum contacting the transfer roller 140A to the downstream side thereof. To the reflective member 12
Limited by 4. In this case, the transfer paper is the transfer roller 140.
By entering the nip portion formed between A and the drum surface, the image forming body is brought into close contact with the toner and electric charges are applied, so that the toner image is not disturbed and stable image transfer is performed as in the previous example.

[0069]

According to the present invention, each image exposure means for forming a latent image on the photoconductor and each uniform exposure stage for performing charge removal are integrally housed in the photoconductor and further exposed by a common light source. As a result, the reliability of the exposure function is improved, the volume is reduced, and the color image forming apparatus is expected to reduce the cost by simplifying the structure.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram of a color image forming apparatus of the present invention.

FIG. 2 is a sectional view showing a relationship between a photosensitive drum and an exposure optical system.

FIG. 3 is a layout diagram of an exposure optical system according to the first invention.

FIG. 4 is a layout diagram of an exposure optical system according to a second invention.

FIG. 5 is a layout diagram of an exposure optical system according to a third invention.

FIG. 6 is a principal part diagram of an exposure optical system according to a third invention.

FIG. 7 is a layout view of pre-charging exposure means according to a fourth invention.

FIG. 8 is a layout view of pre-cleaning exposure means according to the fifth invention.

FIG. 9 is a layout view (1) of the transfer simultaneous exposure means according to the sixth invention.

FIG. 10 is a layout diagram (No. 2) of transfer simultaneous exposure means according to the sixth invention.

[Explanation of symbols]

 10 Photoconductor drum 11 Scorotron charger 12 Exposure optical system 13 Developing device 14A Transfer diagram 14B Static eliminator 19 Cleaning device 19A Blade 100 Light absorbing member 110 Electrode member 121, 122, 123, 124 Reflecting member L1, L2, L3 Exposure means

Claims (18)

[Claims] 1. A color image forming apparatus that repeats charging, image exposure and development on an image forming body to form a toner image on the image forming body in a superimposed manner and then collectively transfers the toner image onto a transfer material. A color image forming apparatus, wherein a body includes a plurality of image exposing means, and a light absorbing member is provided outside an exposure position of the image forming body facing the image exposing means. 2. The color image forming apparatus according to claim 1, wherein the light absorbing member is an electrode to which a voltage is applied. 3. The color image forming apparatus according to claim 2, wherein the applied voltage is higher than the charging potential of the image forming body or the potential of the developing sleeve of the developing means. 4. A color image forming apparatus, wherein a toner image is superposedly formed on the image forming body by repeating charging, image exposure and development on the image forming body, and then the image forming body is collectively transferred to a transfer material. A body includes a plurality of image exposure means, and an electrode member to which a voltage having the same polarity as that of toner is applied is provided outside the exposure position of the image forming body facing the image exposure means. apparatus. 5. The color image forming apparatus according to claim 4, wherein the applied voltage is higher than the charging potential of the image forming body or the potential of the developing sleeve of the developing means. 6. The color image forming apparatus according to claim 4, wherein the electrode member is a light absorbing member. 7. A color image forming apparatus, wherein a toner image is superposedly formed on the image forming body by repeating charging, image exposure and development on the image forming body, and then the image forming body is collectively transferred to a transfer material. The body contains a plurality of image exposing means, and the exposure position of the image exposing means is in a developing container upstream of the developing sleeve of the developing means. 8. The color image forming apparatus according to claim 7, wherein a light absorbing member is provided in the developing container facing the exposure position. 9. An electrode, to which a voltage having the same polarity as that of the toner is applied, which is higher than the charging potential of the image forming body or the developing sleeve of the developing means, is provided in the developing container facing the exposure position. The color image forming apparatus according to claim 7, wherein the color image forming apparatus is a color image forming apparatus. 10. The color image forming apparatus according to claim 9, wherein the electrode is a light absorbing member. 11. A color image forming apparatus for performing a batch transfer onto a transfer material after repeatedly forming a toner image on the image forming body by repeating charging, image exposure and development on the image forming body. The body contains a plurality of image exposing means and pre-charging exposing means, and the exposure position of the pre-charging exposing means is in the cleaning container on the upstream side of the charging means and on the downstream side of the cleaning means. . 12. The color image forming apparatus according to claim 11, wherein a light absorbing member is provided in the cleaning container facing the exposure position. 13. A color image forming apparatus, wherein a toner image is superposedly formed on the image forming body by repeating charging, image exposure and development on the image forming body, and then a batch transfer is performed on a transfer material. The body includes a plurality of image exposure means and pre-cleaning exposure means, and the exposure position of the pre-cleaning exposure means is in a cleaning container on the upstream side of the cleaning means. 14. The color image forming apparatus according to claim 13, wherein the exposure area of the pre-cleaning exposure unit is set on the downstream side of the toner collecting member provided in the cleaning container. 15. The color image forming apparatus according to claim 13, wherein the exposure area of the pre-cleaning exposure unit is set in a cleaning container downstream of the toner spill prevention member sandwiching the cleaning unit. 16. A color image forming apparatus, wherein a toner image is superposedly formed on the image forming body by repeating charging, image exposure and development on the image forming body, and then batch transfer is performed on a transfer material. The body includes a plurality of image exposure means and transfer simultaneous exposure means, and an exposure position of the transfer simultaneous exposure means is set to a downstream side from a position closest to the transfer means. . 17. The color image forming apparatus according to claim 16, wherein the transfer simultaneous exposure unit includes a light source shielding unit, and the exposure region is regulated by the shielding unit. 18. The color image forming apparatus according to claim 17, wherein the exposure area includes a charge eliminating area on a downstream side.