JPS62183475A - Image forming device - Google Patents

Abstract

PURPOSE:To form a color image without generation of color shear by setting up one or more conditions out of electrostatic charge, image exposure, uniform exposure, and development in the succeeding image formation based on the information for photosensitive body surface potential. CONSTITUTION:A potential sensor 18 is arranged on the periphery of a photosensitive body 4 so that a white reference image can be made incident upon the photosensitive body 4 as the image exposure I of irradiated light before the scanning exposure of an original image in an image exposuing device 6. In addition, a switching filter 62 for switcheably inserting a transparent filter,a semitransparent filter or a shielding plate is arranged in an optical path for the incidence of the image exposure I of the device 6 to the photosensitive body 4. Reference image exposure changing its charge and level and uniform exposure for specific light are previously applied to the photosensitive body 4, the surface potential of the photosensitive body 4 is measured during said exposure and based on the information thus obtained, the conditions for a charger 5, the image exposing device 6, uniform exposing devices 7B, 7G, 7R, 7K, dischargers 9Y, 9M, 9C, developing devices 8Y, 8M, 8C, 8K, etc., are stabilized to set up conditions for forming a toner image with high reproducibility. Consequently, a color image can be clearly formed.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention uses a photoreceptor having a distribution layer of color separation functional elements, and after the photoreceptor is charged and imagewise exposed, the photoreceptor is uniformly exposed to specific light. The present invention relates to an image forming apparatus capable of forming a color image on a photoreceptor without color shift by repeating the steps of "developing" and "developing" the electrostatic image formed thereby.

[Background of the invention]

The present inventors have previously completed various inventions regarding the above-mentioned image forming apparatus (% Application No. 59-185440, Application No. 59-187044, Application No. 60-229524, etc.). However, the above-mentioned image forming apparatus requires the charging and image exposure conditions for forming a primary latent image that does not function as an electrostatic image, and the electrostatic Settings such as uniform exposure conditions using specific light to bring out the color image, and development conditions to develop the electrostatic image to high density without affecting other color separation images and without fogging Charging in the image forming apparatus described in Japanese Patent Application Nos. 58-183152 and 58-184381, in which charging, image exposure, and development are repeated each time a color separated image is formed using a photoreceptor that does not have a distribution layer of separation functional elements.

This method has the problem of being more troublesome than setting conditions for image exposure, uniform exposure, development, etc.

[Purpose of the invention]

The present invention has been made in order to solve the above-mentioned problems, and uses a photoreceptor having a distribution layer of color separation functional elements that allows easy setting of conditions such as charging, image exposure, uniform exposure, and development. The purpose is to provide an image forming apparatus with

[Structure of the invention]

The present invention uses a photoreceptor having a distribution layer of color separation functional elements, and after charging the photoreceptor and imagewise exposure, uniform exposure with specific light and development of the electrostatic image formed thereby. In a device that repeatedly forms color images on a photoreceptor,
The photoreceptor is subjected to reference image exposure and specific light uniform exposure in which charging and level change in advance, and charging, image exposure, and uniform exposure are performed in subsequent image formation based on information on the surface potential of the photoreceptor during that period.

The image forming apparatus is characterized in that one or more of the developing conditions are set, and with this configuration, the above object is achieved.

〔Example〕

Hereinafter, the present invention will be explained based on illustrated examples. FIGS. 1 to 4 are a partial sectional view schematically showing an example of the layer structure of a photoreceptor used in an image forming apparatus of the present invention, and FIGS. FIG. 6 is a partial plan view of a color separation layer showing an example of the distribution shape of the color separation functional elements of the photoreceptor, FIG. 7 is a schematic configuration diagram showing an example of the image forming apparatus of the present invention, and FIG. 8 is a developing device. FIG. 9 is a synchronization chart of operations performed in advance to set image forming conditions, and FIG. 10 is a chart of changes in surface potential of the photoreceptor obtained by the operations shown in FIG. 9.

In FIGS. 1 to 4, 1 is a conductive member formed into an appropriate shape structure as required, such as a cylindrical shape or an endless belt shape, and 2 is a photoconductive layer made of an inorganic photoconductor or an organic photoconductor. ,
3 is an insulating layer including a layer 3a consisting of a distribution of minute color separation filters of red (8), green (Gl, blue (B), etc.) formed from various polymers, resins, etc. and colorants such as dyes and pigments; The insulation periphery 3 of the photoreceptor 4 in FIG.
printed on top.

The insulating layer 3 of the photoreceptor 4 shown in FIG.
has a transparent insulating layer under the insulating layer 3 in FIG. 1, and the insulating layer 3 of the photoreceptor 4 in FIG. 3 further has a transparent insulating layer on the insulating layer 3 in FIG. The insulating layer 3 of the photoreceptor 4 shown in FIG. 4 has a transparent insulating layer on top of the insulating layer 3 shown in FIG.

The distribution shape of the R/G2B filters, etc. in the color separation layer 3a of the insulating layer 3 is not particularly limited, but the mosaic distribution shown in FIGS. 5 and 6 is suitable for reproducing delicate multicolor images. It is used in many ways.

The individual sizes of the R, G, B filters, etc. are in the range of 10 to 200 μm, particularly 50 μm to 100 μm, as shown by t in the figure.
The range of m is considered appropriate in terms of ease of forming a distribution pattern, image resolution, and color reproducibility.

The image forming apparatus shown in FIG. 7 includes a charger 5, an image exposure device 6, and a uniform exposure device 7B, 7 around a drum-shaped photoreceptor 4 having an insulating layer 3 containing color separation R3a as described above. G
t 7 Rr 7 K, a non-contact method in which a -component or two-component developer is formed to a thickness that does not contact the surface of the photoreceptor 4, and an alternating current bias is used as a development bias to make the toner fly from the developer layer. Developing devices 8Y, 8M, 8C, 8K as shown in detail in FIG. 8 perform development, and dischargers 9Y, 9 for smoothing the surface of the photoreceptor 40 after development.
M.

90. Pre-transfer treatment to make it easier to transfer the finally formed toner image onto the recording paper P using a corona discharger and an exposure lamp with infrared light that has good permeability even for white light or a single layer of toner. Device 1o, transfer device 11, separator 12, pre-cleaning static eliminator 13 using an exposure lamp and a corona discharger
, a cleaning device 14 is provided, and a color image or a monochrome image is formed 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 (-order charging).

This corona discharge of the charger 5 is a positive discharge when an n-type semiconductor such as cadmium sulfide is used for the photoconductive layer 2 of the photoreceptor 4, and a positive discharge when a p-type semiconductor such as selenium is used. If there is a negative discharge.

An image exposure device 6 exposes an image onto the surface of the photoreceptor 4 which is primarily charged. The image exposure device 6 performs slit exposure using reflected light emitted from a reciprocating document by either an optical system or a document table.

The present invention is not limited to this, and it is also possible to use a method in which the original passes over a platen, or to perform image exposure using transmitted light from the original. When the image exposure device enters the image exposure device 6, the discharger 61 of the image exposure device 6 performs corona discharge of alternating current or direct current of opposite polarity to the charger 5 (secondary charging). As a result, a primary latent image consisting of charge density is formed on the photoreceptor 4. This sublayer image does not function as an electrostatic latent image for development. The discharge device 61 may be provided on the downstream side of the incident position of the image exposure operator.

- The uniform exposure device 7B uniformly applies blue light having a specific amount of light to the next layer image forming surface.

Due to this uniform exposure to the blue light, a potential pattern is generated on the surface of the B filter portion of the photoreceptor 4 from the previously formed primary latent image. This potential pattern, that is, the electrostatic image is developed by the developing device 8Y containing yellow toner to form a yellow toner image made of the yellow toner adhered to the surface of the B filter portion.

Next, the potential on the surface of the photoreceptor 4 on which the yellow toner image has been formed is smoothed by the discharger 9Y, and green light having a specific amount of light is uniformly incident on the smoothed surface by the uniform exposure device 7G. . As a result, the G of photoreceptor 4 is now
Since a potential pattern is generated on the surface of the filter portion, the potential pattern is transferred to the developing device 8M containing magenta toner.
A magenta toner image consisting of magenta toner adhered to the surface of the G filter portion is formed.

Further, the potential of the surface on which the magenta toner image has been formed is smoothed by the discharger 9M, and red light having a specific light amount is uniformly incident on the smoothed surface by the uniform exposure device 7R. Since a potential pattern is generated on the surface of the R filter portion, this potential pattern is developed by the developing device 8C containing cyan toner to form a cyan toner image made of the cyan toner adhered to the R filter portion. As a result, a color image is formed on the photoreceptor 4 by combining yellow and magenta cyan toner images.

If you want to increase the contrast of a color image,
The electric potential of the surface on which the above-mentioned cyan toner image is formed is transferred to a discharger 9.
The paper is smoothed by C, and a uniform exposure device 7K uniformly applies white light or infrared light in an amount sufficient to pass through the attached toner and each filter. . As a result, a slight potential pattern is generated on the surface of the B, G, and R filter portions of the photoreceptor 4, which compensates for the dot portions of the original image, and this potential pattern is developed by the developing device 8 containing black toner. Then B, G.

A black toner image consisting of black toner adhered to the R filter portion is formed. As a result, a color image with high image density consisting of a combination of yellow, magenta, cyan, and black toner images is formed on the photoreceptor 4 within one rotation of the photoreceptor 4.

It should be noted that the monochrome image formed in the above process, especially the monochrome image other than black, has a lower resolving power than the monochrome image formed with an image forming apparatus using a photoreceptor that does not have a distribution layer of color separation functional elements. It is likely that the concentration will be poor. Therefore, when forming a monochromatic image, uniform exposure of blue, green, red light, or white light is performed after image exposure, and thereby the B of the photoreceptor 4 is
,G.

The potential pattern formed on the R filter portion is transferred to the developing device 8.
If one or two of Y, 8M, and 80.8 are used for development, a monochrome image can be formed with the same resolution and density as in a monochrome copying machine. In the image forming apparatus shown in FIG. 7, formation of such a monochromatic image is performed on the photoreceptor 4, apart from cyan and black monochromatic images.
This is done within two revolutions. In order to perform this also within one rotation, the uniform exposure device 7B should be capable of performing uniform exposure with white light, or the uniform exposure device 7B should be aligned with the uniform exposure device 7B to uniformly expose white light or infrared light. An exposure device may be provided. In addition, when forming a color image as described above within four rotations of the photoreceptor 4, the dischargers 9Y19M and 90 are omitted, and the discharger 61 of the image exposure device 6 is used to smooth the surface potential after development. You can also do

The toner image formed on the photoreceptor 4 through the above steps is
Transfer is facilitated by the transfer pre-processing device 10, and the transfer device 11 transfers the toner image onto the recording paper P fed by the paper feeder 1sK. The toner is separated and transported by the transport means 16 to the fixing device 17, where the toner is fixed, 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 provided as necessary, and then the cleaning blade or cleaning roller of the cleaning device 14 comes into contact with the surface of the photoreceptor 4 to remove any remaining static electricity. After the toner is removed, it is subjected to the next image forming process.

The image forming apparatus shown in FIG. 7 further includes a potential sensor 18 around the photoconductor 4, and uses an image exposure device 6 to expose the photoconductor using light emitted from a white reference image before scanning and exposing the original image. 4, and a switching filter 62 is provided for selectively inserting a transparent filter, a translucent filter, and a shielding plate into the optical path of the image exposure device 6 that enters the photoreceptor 4. Therefore, prior to the above-mentioned toner image forming step, the photoreceptor 4 is exposed in advance to a reference image whose charge and level changes and is uniformly exposed to specific light, and the surface potential of the photoreceptor 4 is measured during this time. , based on the information, charger 5, image exposure device 6, and even uniform exposure devices 7B and 7G.
, 7R, 7K, discharger 9Y19M, 9G, developing device 8Y
, 8M, 80.

Conditions such as No. 8 can be set so that a toner image with good reproducibility is formed stably. This is done by rotating the photoreceptor 4 in advance, and during that time, for example, exposing the surface of the photoreceptor 4 to a charged p reference image, uniform exposure, etc. at the timing shown in FIG. The surface potential at each position of the photoreceptor 4 as shown in FIG. This is carried out by setting the conditions for the toner image forming process via a drive circuit using such a method.

■ The discharge conditions of the charger 5 are set so that the potential at position a, which is only charged by turning on the charger 5, is a predetermined potential, and the discharge conditions of the charger 5 are set so that the potential of the position a, which is only charged by turning on the charger 5, is set to a predetermined potential. The switching filter 62 sets the light emission amount to the initial setting value.
By sequentially switching the filter to a shielding plate, a semi-transparent filter, and a transparent filter, one or more of the potentials at positions b, d, and f where black, gray, and white reference image exposure are made are respectively set to predetermined potentials. The discharge conditions of the discharger 61 are set so as to have the potential. Then, with respect to the black reference image exposure incident position, the uniform exposure device 7K performs sufficient uniform exposure with light passing through all the filters at two positions, and the potential difference between the d and f positions is set to a predetermined potential difference, respectively. Reset the discharge conditions of the charger 5 as follows.

This results in j) b, d.

If the potential at position f deviates from the predetermined potential, the discharge conditions of the discharger 61 are reset so that the potential is again at the predetermined potential. By repeating the above, the potential contrast and the secondary band ta
Adjust the position. For this purpose, the operation shown in FIG. 9 during this period is repeated so that the state from position b to position δ is repeatedly reproduced.

Next, the light emission conditions of the image exposure lamp are set so that the potentials at positions C and e, where the uniform exposure device 7K has sufficiently uniformly exposed the reference image exposure incident positions of gray and white, respectively, are set to a predetermined potential. Set. As described above, the charging by the charger 5, the discharge by the discharger 61, and the light amount for black, gray, and white reference image exposure were adjusted.

Furthermore, uniform exposure by the uniform exposure device 7BIC was applied h
Alternatively, the light emitting conditions of the uniform exposure device 7B are set so that the potential at the i position is a predetermined potential, and the discharger 9Y is set so that the potential at the j or position where discharge is performed by the discharger 9Y is a predetermined potential. Furthermore, the light emitting conditions of the uniform exposure device 7G are set so that the potential at the position t or m where the uniform exposure by the uniform exposure device 7G is incident is a predetermined potential, and The discharge conditions of the discharger 9M are set so that the potential at the n or ○ position where the discharge occurs is set to a predetermined potential, and the potential at the p or q position where uniform exposure is applied by the uniform exposure device ft7H is set to the predetermined potential. The light emission conditions of the uniform exposure device 7 are set so that
The discharge conditions of the discharger 90 are set so that the potential at the position is a predetermined potential.

Setting of the uniform exposure conditions described above is performed as follows.

If the uniform exposure intensity of each of the uniform exposure devices 7B, 7G, and 7R is increased, in principle, the potential will be saturated at approximately - the potential contrast between the b, d, f positions and the C position. , if the intensity is increased indefinitely, in reality, the wavelength of uniform exposure or the spectral distribution of the filter is not ideal, so a potential pattern will occur in other filter parts, and as a result, the potential will change to the above-mentioned potential contrast. This exceeds 1/3 of the total. On the other hand, if development is performed and the toner spreads and adheres to other filter parts, the toner partially blocks the uniform exposure. Uniform exposure requires that the amount of light be sufficient to produce a potential pattern even with this shielding. Therefore, there is an appropriate value for the amount of light for uniform exposure. The appropriate amount of light is a scene where the generated potential is 2 to 10% higher than the potential contrast at the C position, or a scene where the potential contrast is approximately 1/3 of the potential contrast at the C position. 1.5-1
Set the light intensity to 0x. Note that, regarding the predetermined potential in this case or the potential of about 14° of the potential contrast at the C position, the dark decay of the photoreceptor 4 is also taken into consideration.

(2) The discharge conditions of the charger 5 and the discharger 61 and the light emission conditions of the image exposure lamp are set in the same manner as in (2) so that the potentials at the O+e+g positions mentioned above are set to predetermined potentials. After that, without operating the dischargers 9Y, 9M, 90 and the uniform exposure device 7K, the uniform exposure devices 7B, '7Cr, and 7R are operated separately, and the generated potential is used to Set the light emission conditions, and then set the dischargers 9Y, 9M, and 9G.
Set each discharge condition to smooth the potential. This means that the uniform exposure device 7B and the discharger 9Y in FIG. Turn it off before turning it on, and set the light emission condition from the potential at the h/t, p position or ir m + q position in the same way as in ■, and set the discharge condition from the potential at the ] + n + C position or +o + s position. This is done by setting .

■Dischargers 61.9Y, 9M, and 9 (3) use a scorotron that easily smoothes the surface potential of the photoreceptor 4 to keep these discharge conditions constant, and then set the potentials at positions e, g, or C to predetermined values, respectively. The discharge conditions of the charger 5 and the light emission conditions of the image exposure lamp are set so that the electric potential is maintained, and the light emission conditions of the uniform exposure devices 7B, 7G, 7R, and 7 are then set in the same manner as in (1) or (2).

As described above, the charger 5, the discharger 61 of the image exposure device 6, the image exposure lamp, the uniform exposure devices 7B, 7G,
7R, 7, dischargers 9Y, 9M.

9C conditions can be set. The predetermined potential and the predetermined potential difference in these methods are not limited to fixed values, but include values within a fixed range. As mentioned earlier, the predetermined potentials for setting the light emission conditions of the uniform exposure devices 7B, 7G, and 7H are as follows.
The charger 5 and the discharger 61 are discharged, and neither image exposure nor uniform exposure is applied at a predetermined potential at position b, and uniform exposure of a sufficient amount of white light or infrared light by the uniform exposure device 7K is performed. The difference between the predetermined potential at the 9g position and the predetermined potential at In addition, in the methods ① to ②, it is necessary to set the value such that the potential difference that occurs due to dark decay of the photoreceptor 4 becomes smaller in the later stages. Uniform exposure device 7B.

After uniform exposure by 7G and 71.7K, development may be performed by the developing devices 8Y, 8M, 8C, and 8K, respectively. Developing device f8Y, 8M.

The following method is used to set the developing bias at 80.8.

(2) Preferably, a developing device 8Y in the toner image forming step.

α corresponds to the state in which 8M and 80.8K are used for development.

The DC component of each developing bias is set to a value equal to the white original potential at the β, γ, and δ positions. The IR m + q r C positions where the image exposure was performed are developed by the corresponding developing devices 8Y, 8M, 8G and 8, respectively, and the toner image density at those positions is detected by a density sensor 19 consisting of a light emitting element and a light receiving element. The AC component voltage, frequency, etc. are set based on this information.

(2) Most simply, the developing bias DC component for the developing devices 8Y to 8 is set to be equal to the predetermined potential at position b, which provides a non-exposure potential, and the AC component is set in the same manner as in (2).

and input to the CPU. Then, the CPU sets the developing bias via the drive circuit.

Developing by the developing devices 8Y to 8K will be explained with reference to FIG.

In the developing device shown in FIG. 8, at least one of a developing sleeve 81 and a magnet 82 having N and S magnetic poles on the inner circumferential surface of the developing sleeve 81 rotates, and the developer reservoir is rotated by the magnetic force of the magnet 82. The developer adsorbed on the surface of the developing sleeve 81 from the paper 83 is conveyed in the direction of the arrow. During the conveyance of the developer, the amount of conveyance is regulated by the layer thickness regulating blade 84 to form a developer layer, and the developer layer is applied to the photoconductor 4 in the developing area where the developing sleeve 81 faces. Develop according to the pattern. During development, a developing bias voltage is applied to the developing sleeve 81 from a drive circuit.

Further, if necessary, even when no development is performed, toner may be transferred from the developing sleeve 81 to the photoreceptor 4 or
A bias voltage may be applied to the developing sleeve 81 in order to prevent the toner from migrating to the developing sleeve 81. That is, while the developing device 8Y is developing an electrostatic image, the other developing devices 8M, 80.8, etc. are kept in a state in which they do not perform development. This can be done by disconnecting the developing sleeve 81 from the drive circuit and placing it in a floating state or grounded, or actively
Charging of the toner is achieved by applying only a DC bias voltage of the same or opposite polarity to the toner, and it is particularly preferable to apply a DC bias voltage of the opposite polarity to that of the toner. Since the developing devices 8M and 8C18 are also designed to perform development under non-contact jumping development conditions, the developer layer on the developing sleeve 81 does not need to be particularly removed. but,
A developing device that is not in use may be stopped during this period, may be moved away from the photoreceptor, or the developer may be removed from the sleeve.

85 is a cleaning blade that removes the developer layer that has passed through the developing area from the developing sleeve 81 and returns it to the developer reservoir 83; 86 is a stirring blade that agitates the developer in the developer reservoir 83 to make it uniform and triboelectrically charges the toner. A means 88 is a toner replenishing roller that replenishes toner from the toner hopper 87 to the developer reservoir 83.

The developer used in such a developing device may be a so-called one-component developer consisting only of toner, or a two-component developer consisting of toner and a magnetic carrier. For development, a method may be used in which the developer layer, that is, the surface of the photoreceptor is directly rubbed with a magnetic brush, but especially after the second development, the developer layer is A developing method that does not contact the photoreceptor surface, such as U.S. Pat. No. 3,893,418,
Japanese Unexamined Patent Publication No. 18656/1983, especially Japanese Patent Application No. 58/57
No. 446, Japanese Patent Application No. 1982-238295, Japanese Patent Application No. 1983-
'238296, and Japanese Patent Application Nos. 58-139974 and 59-1399 for superimposition on the same latent image.
It is preferable to use the method described in each specification of No. 75. These methods use a one-component or two-component developer containing non-magnetic toner that can be colored freely, create an alternating electric field in the development area, and perform development without contact between the photoreceptor and the developer layer. be. In this non-contact development, the gap between the developing sleeve and the surface of the photoreceptor is set to be larger than the layer thickness of the developer layer on the developing sleeve (provided there is no potential difference between the two), and this gap, layer thickness Development is carried out under various conditions as described above.

The color toner used for development is made using known techniques and consists of known binding resins, organic and inorganic pigments, various chromatic and achromatic colorants such as dyes, and various magnetic additives that are commonly used in toners. Toner for electrostatic development can be used, and the carrier can be iron powder, ferrite powder, which are usually used for electrostatic images, those coated with resin, or those with magnetic material dispersed in resin. Among various known carriers, preferably a magnetic carrier having a high resistivity of 10 9 cm or more and a small particle size of 5 to 50 μm can be used.

In addition, the applicant filed the patent application No. 58-24966 earlier.
The developing method described in No. 9, No. 240066 may be used.

In the image forming apparatus shown in FIG. 7, conditions such as charging, image exposure, uniform exposure, development, etc. are set in advance by the methods described in (1) to (3) above.
In the subsequent toner image forming step, a toner image can be stably formed with good reproducibility. This process for setting conditions may be performed each time the copy button is operated, but since it does not need to be performed that frequently, it may be performed each time the image forming apparatus is powered on, or by pressing the condition setting command button on the operation panel. It is sufficient to set the setting value so that it is executed only when a command based on the command is issued, and to store the obtained set value. By doing this, it is not only possible to stably obtain images depending on the adjustment conditions, but also to easily and stably obtain images with different tones, shading, etc. by changing the above adjustment conditions according to your preference. You can also do it.

The image forming apparatus of the present invention is not limited to one in which all the conditions of charging, image exposure, uniform exposure, and development can be set in advance, but may be one in which only some of the conditions can be set. Also,
Uniform exposure device 7 in the process for setting conditions in FIG. 9
Even if the incident positions of the uniform exposures B, 7G, and 7H are completely shifted to form potential patterns at different positions, and furthermore, a plurality of potential sensors are used, the conditions can be set substantially unchanged. In addition, when developing in the process for setting conditions, it is recommended to perform development only by the developing device 8K to stabilize the output of the density sensor and to ensure that the cleaning device 14
This is preferable from the viewpoint of reducing the burden on other people.

The present invention is disclosed in Japanese Patent Application No. 60-22952 as an image forming method.
Primary charging and secondary charging as described in No. 4.

The present invention can be similarly applied to an image forming apparatus in which after image exposure, charging for smoothing, whole surface exposure with specific light, and development are repeated.

In addition, the photoreceptor has a filter provided on the conductive substrate side of the photoconductive layer, and image exposure and full-surface exposure are performed from the filter side (Japanese Patent Application No. 199547/1983).
and other configurations (patent application 1981-198166.1981)
67.201084). Furthermore, the photoconductive layer is not limited to a single layer, but has a functionally separated structure consisting of a charge generation layer and a charge transfer layer (Japanese Patent Application No. 60-24
No. 5178). Alternatively, the photoreceptor may have a structure in which the photoconductive layer has a color separation function (Japanese Patent Application No. 1983-
201085.60-245177).

〔Effect of the invention〕

According to the image forming apparatus of the present invention, charging and image exposure can be performed.

The excellent effect of being able to easily set appropriate conditions such as uniform exposure and development, and to form stable and clear color images with no color shift can be obtained.

[Brief explanation of drawings]

1 to 4 are partial cross-sectional views each schematically showing an example of the layer structure of a photoreceptor used in the image forming apparatus of the present invention, and FIGS. Partial plan view of the color separation layer showing an example of the distribution shape, No. 7
FIG. 8 is a schematic configuration diagram showing an example of the image forming apparatus of the present invention.
The figure is a partial sectional view showing an example of a developing device, and FIG. 9 is a synchronization chart of operations performed in advance to set image forming conditions.
FIG. 10 is a chart of changes in surface potential of the photoreceptor obtained by the operation shown in FIG. DESCRIPTION OF SYMBOLS 1... Conductive member, 2... Photoconductive layer, 3...
...Insulating layer, 3a...Color separation layer, 4...
・Photoreceptor, 5... Charger, 6... Image exposure device, 7B, 7G, 7R, 7K... Uniform exposure device, 8Y, 8
M, 80.8K...Developing device, 61.9Y, 9M, 9
0... Discharge device, 10... Transfer pretreatment device, 11.
... Transfer device, 12... Separator, 13... Pre-cleaning static eliminator, 14... Cleaning device, 15... Paper feeding device, 18... Potential sensor,
19...Concentration sensor, 62...Switching filter. Patent applicant Roku Konishi Photo Industry Co., Ltd. Figure 1 Figure z Figure 3 Figure 4 Figure 7

Claims (1)

[Claims] A photoreceptor having a distribution layer of color separation functional elements is used, and after the photoreceptor is charged and imagewise exposed, uniform exposure with specific light and development of the electrostatic image formed thereby are repeated to expose the photoreceptor to light. In an apparatus for forming a color image on a body, the photoreceptor is exposed in advance to a standard image with varying charge and level and uniformly exposed to a specific light, and information on the surface potential of the photoreceptor is used during subsequent image formation. An image forming apparatus characterized in that one or more of charging, image exposure, uniform exposure, and development conditions are set.