JPS62296169A - Picture forming device using photosensitive body with color separating function - Google Patents

Abstract

PURPOSE:To improve the color separating function of a photosensitive body so as to form a clear colored picture without replacing developing devices with each other, by constituting uniform exposure devices with liquid-crystal cells which selectively transmit any specific rays of light in such a way that the specific rays of light can be made incident to the photosensitive body by switching. CONSTITUTION:A color separating layer 1c composed of filters of color separation functioning elements of three colors is provided on the base body 1a of a photosensitive body 1 and electrostatic latent images are formed in each element of the photosensitive body by means of three exposure devices 5B, 5G, and 5R. The latent images are respectively developed with three developing devices. Rays of light of a panchromatic light source 50 are made incident to liquid-crystal cells 51 composed of laminated three sets of composite cells 51B, 51G, and 51R and each color is made incident to the photosensitive body by adjusting voltages V. Therefore, by respectively switching each uniform exposure device 5 so that rays of light other than blue, green, and red can be made incident to the photosensitive body, a colored picture having no color shifting which is obtained by color-converting the picture of an original can be formed clearly without replacing the three developing devices with each other.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an image forming apparatus using a photoreceptor having a color separation function, and particularly relates to an image forming apparatus that performs color conversion on an original image. The present invention relates to an image forming apparatus that can easily form images.

[Background of the invention]

An image forming apparatus using a photoreceptor with a color separation function charges the photoreceptor and exposes it to image light to form a primary latent image, and then uses a beam of specific light to draw a color-separated electrostatic image from the primary latent image. A color image consisting of a composite of multiple color toner images is formed on a photoconductor by repeating the process of exposure to light and developing the electrostatic image. Compared to color copying machines and the like, it has an excellent feature of being able to reproduce color images clearly and without color shift.

On the other hand, there are quite frequent requests to create images that are color-converted from original images for reasons such as color design of 1-inch rears of clothing, cars, home appliances, and the like. It is preferable if this requirement is satisfied by the above-mentioned image forming apparatus because a color-converted color image can be clearly obtained. However, forming a color-converted image using a conventional image forming apparatus requires replacing the developing device or the uniform exposure device, which is cumbersome to operate.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned background circumstances, and provides an image using a photoreceptor having a color separation function that can easily satisfy the request to create an image that is color-converted from an original image. The purpose is to provide a forming device.

[Structure of the invention]

The present invention uses a photoreceptor having a color separation function, and after forming a primary latent image by charging and imagewise exposing the photoreceptor, a specific beam of light is used to extract a color-separated electrostatic image from the primary latent image. In an apparatus for forming a color image consisting of a composite of a plurality of color toner images on a photoreceptor by repeatedly performing exposure to light and developing the electrostatic image, each uniform exposure device performs uniform exposure to the specific constant light. An image forming apparatus using a photoreceptor having a color separation function is characterized in that it uses a uniform exposure device that can switch any specific light to enter the photoreceptor, and with this configuration, the above-mentioned purpose can be achieved. achieve.

〔Example〕

Hereinafter, the present invention will be explained based on illustrated examples.

FIG. 1 is a schematic front view of the configuration of an example of the image forming apparatus of the present invention, and FIG. 2 is a partial cross-sectional view of an example of the layer configuration of the photoreceptor.
3 and 4 are partial plan views showing an example of the filter distribution shape of the color separation layer of the photoconductor, FIG. 5 is a potential change chart on the surface of the photoconductor in the color image forming process, and FIGS. 6 and 7 Each figure is a schematic front view showing an example of a specific light uniform exposure device used in the image forming apparatus of the present invention.

In the image forming apparatus shown in FIG. 1, the drum-shaped photoreceptor l has a layer structure as shown in FIG.

That is, a photoconductor layer 1b is provided on an electroconductive substrate la, and a blue (B) color separation functional element is applied thereon.

Color separation layer 1 consisting of distribution of green (G) and red (R) filters
This is a layered structure in which an insulating surface layer 1d having a thickness of c is provided. The color separation layer IC is covered with an insulating transparent protective layer 1e to prevent the B, G, and R filters from deteriorating due to ozone generated from the charger during image formation or shadows from the image exposure light source. There is. Regarding the distribution shape of the B, G, and R filters in the color separation layer IC, a mosaic distribution with l in the range of 10 to 200 μm as shown in Figures 3 and 4 improves image resolution and color reproducibility. It is preferably used from this point of view.

A preferred method for forming the photoreceptor 1 as described above is to form a color separation layer IC with the distribution pattern shown in FIGS. This is a method of attaching it onto the optical thick electrical layer lb using a highly insulating adhesive or pressure-sensitive adhesive that is transparent to external light. However, the invention is not limited to this, and the insulating surface layer 1 has a color separation layer 1c made of resin, dye, or pigment by direct printing, photoresist, vapor deposition, etc. on the photoconductor layer lb, for example.
d or without adhesion of the film having the color separation layer 1c, the photoconductor layer lb is fixed by mechanical fixing means.
It may also be provided above.

The distribution shape of the color separation functional elements is not limited to the examples shown in Figures 3 and 4, and the numbers of B, G, and R filters are not all equal. The number of G filters may be increased somewhat compared to the number of filters.

The charger 2 performs corona discharge on the surface of the photoreceptor 1 rotating in the direction of the arrow to uniformly charge the surface. This corona discharge is a positive discharge when the photoconductor layer lb of the photoreceptor 1 is made of an n-type semiconductor such as cadmium sulfide, and a negative discharge when it is made of a p-type semiconductor such as selenium.

The image exposure device 3 scans and exposes the original O by reciprocating the optical system or the original platen left and right, and uses the reflected light from the original O for image exposure I.
Not only when the light enters the surface of the photoreceptor 1 charged by the charger 2, but also when the scanning exposure of the original ○ is performed as the original 0 passes over the platen, the transmitted light of the original 0 is converted into an image. Exposure (■) may also be used. Furthermore, in the case of a fixed optical system, a light converging element array (trade name: CellHoc) can also be used in the optical system. The image exposure lamp 31 includes a halogen lamp and a xenon lamp.

A fluorescent lamp with a panchromatic emission spectrum.

A light source such as a combination of fluorescent lamps having B, G, and R spectra is used.

A charger 4 provided at the incident position of the image exposure I supplies a direct current or alternating current corona with a polarity substantially opposite to that of the corona discharge of the charger 2, at least while the image exposure I is incident on the surface of the photoreceptor 1. Perform discharge. The charger 4 may also be provided immediately after the incident position of the imagewise exposure I to cause corona discharge to at least the incident surface of the (&exposure I).

As a result, a primary latent image is formed on the photoreceptor 1 by color-separating the original ○, which does not function as an electrostatic image developed with toner.

The uniform exposure device 5B uniformly applies blue light to the primary latent image forming surface of the photoreceptor 1. This uniform exposure to blue light causes a potential pattern, that is, an electrostatic image to which toner adheres during development, to be generated from the primary latent image only in the B filter portion of the photoreceptor 1.

The developing device 6Y develops this electrostatic image using yellow toner. As a result, a yellow toner image consisting of yellow toner adhered to the surface of the B filter portion of the photoreceptor 1 is formed. The developing device 6Y includes a developing device 6M, which will be described later.
, 6C, similarly, a layer of -component or two-component developer is formed on the developing sleeve to a thickness that does not contact the surface of the photoreceptor l, and the toner is ejected from the developer layer by using an alternating current bias as the developing bias. A developing device that performs so-called non-contact development, in which the toner is allowed to adhere to the photoreceptor 1, is preferably used. However, it is not limited to this.

The charger 7Y is used to prevent color mixing due to the fact that even if the potential of the electrostatic image decreases due to the adhesion of toner charged to the opposite polarity, it will still be at the potential to which the toner will adhere when development is performed next time. , a photoreceptor 1 on which a yellow toner image is formed
A discharge of the same polarity as that of the charger 4 is applied to the surface of the charger 4 to smooth the potential to a level at which toner does not adhere.

The uniform exposure device 5G uniformly applies green light to the surface of the photoreceptor 1 whose potential has been smoothed. As a result, a potential pattern is generated from the primary latent image only in the G filter portion of the photoreceptor 1.

The developing device 6M develops the above-described potential pattern with magenta toner. As a result, a magenta toner image consisting of magenta toner adhered to the surface of the G filter portion of the photoreceptor 1 is formed.

Like the charger 7Y, the charger 7M smoothes the surface potential of the photoreceptor 1 on which the magenta toner image is formed. Then, the uniform exposure device 5R uniformly applies red light to the surface of the photoreceptor 1 whose potential has been smoothed. As a result, a potential bounce is generated only in the R filter portion of the photoreceptor 1 from the primary latent image.

The developing device 6C develops this potential pattern using cyan toner. As a result, a cyan toner image consisting of cyan toner adhered to the surface of the R filter portion of the photoreceptor 1 is formed.

As described above, a color image consisting of yellow, magenta, and cyan toner images corresponding to document 0 is formed on the surface of photoreceptor 1 without color shift or color mixture.

A pre-transfer system comprising an AC corona discharger and an exposure lamp that irradiates light, such as white light or infrared light, that passes through the B, G, and R filters of the photoreceptor 1 and makes the optically thick electrical layer 1b conductive. The processing device 8 makes it easy to transfer the formed toner image onto a transfer material P fed by a paper feeding device (not shown), the transfer device 9 transfers the toner image onto the transfer material P, and the separator 10
Separates the transfer material P onto which the toner image has been transferred from the S light body 1. The separated transfer material P is sent to a fixing device (not shown), the toner image is fixed thereon, and the transfer material P is discharged outside the machine.

A pre-cleaning static eliminator 11 having the same FM configuration as the transfer pre-processing device 8 removes static electricity from the surface of the photoreceptor 1 to which the toner image has been transferred to facilitate the removal of toner remaining on the surface. The residual toner is removed from the surface of the photoreceptor 10 using a blade or the like. As a result, the photoreceptor 10
The surface is again ready for the next image formation.

FIG. 5 shows the change in surface potential of the photoreceptor 1 during the color image forming process described above when the photoreceptor layer 1b of the photoreceptor 1 is made of a p-type semi-thick material such as 5e-Te photoconductor. , Time Rainbow. The primary charging from tl to tl is the change while the surface of the photoreceptor 1 passes through the charger 2, and the dark decay from time L1 to t2 is the charge injection and the change during the time when the primarily charged surface reaches the charger 4. Change due to dissipation of injected charge, secondary charging/a exposure curve from time t2 to t3 ■
L and Vo indicate changes in portions corresponding to the bright and dark portions of the image exposure I while passing through the charger 4. Due to this secondary charging, the surface potential of the photoreceptor 1 is substantially smoothed, and there is no potential pattern to which toner adheres. Although a decrease in potential contrast due to dark decay is observed after time L:I, this is omitted in FIG. Uniform exposure from time t to time t is a change in bright area potential (■) and dark area potential (■) due to uniform exposure to blue light, and development from time t4 to L5 is caused by yellow toner by developer 6Y. Changes due to the adhesion of
The change in smoothing due to the uniform exposure from time t to the change due to -ffi exposure of green light, time t
The development from 7 to t8 is due to the adhesion of magenta toner by the developing device 6M, and the time 1. From t,
The recharging up to t is a change in smoothing by the charger 7M, the uniform exposure from time to tlG is a change due to uniform exposure to red light, and the development from time tI0 to t is a change in smoothing by the charger 7M. This shows changes due to the adhesion of cyan toner. Here, the bright area potential ■ is the original O
It shows not only the potential of the part where the bright part of the image exposure (■) is incident (but also the part of the white part of the document table or platen cover where the image exposure I is incident), at least for time t, after which toner will not adhere. The potential is maintained and hardly changes.Therefore, no black frames etc. are generated on the transfer material P.In addition, the potential of the part where the gradation part between the bright part and the dark part of image exposure I is incident is the bright part potential. Since the potential is intermediate between VL and the dark area potential V, an image with gradation can also be obtained.

In the above image forming apparatus, the uniform exposure devices 5B and 5G
, 5R has the configuration shown in FIG. 6 or 7. The uniform exposure device shown in FIG. 6 uses light such as cold cathode discharge tubes, fluorescent lamps, halogen lamps, etc. that emit panchromatic light.
X50 and the voltage Va applied to each DAP type cell,
A DAP type cell is sandwiched between cholesteric cells that can transmit panchromatic light and transmit specific blue, green, and red light by controlling Vc and V++.
For example, by adjusting the voltages VB, VG, V, and l applied to the DAP type cell, the composite cell 51B can be changed to The photoreceptor 1 is placed in a specific light transmission state, and the composite cells 51G and 51R are placed in a panchromatic light transmission state.
blue light can be incident on the

Alternatively, the composite cell 51G may be set to a specific light transmitting state, the composite cells 51B and 51R may be set to a panchromatic light transmitting state, and green light may be incident on the photoreceptor 1; the composite cell 51R may be set to a specific light transmitting state; It is also possible to make the composite cells 51B, 51G transmit panchromatic light so that red light is incident on the photoreceptor 1, or to make the composite cells 51B, 51G, 51R
It is also possible to make all of the panchromatic light transparent so that the panchromatic light is incident on the photoreceptor 1. Note that voltage can be easily applied to the DAP cell by pressing a color conversion key on an operation board (not shown). In other words, the signal sent from the operation board is sent to a control device (not shown), and is controlled by it. Any of the above-mentioned incident states can be obtained by the T;1 device controlling the voltages V++, VG, and VR applied to the DAP type cell. The incident state of panchromatic light is used when forming a monochrome image or when adding contrast to a color image using black toner.

The uniform exposure apparatus shown in FIG. 7 has a structure in which light emitting elements 50B and 500.5OR such as LEDs that emit blue light, green light, and red light, respectively, are arranged on a common substrate 52 in the width direction of the photoreceptor 1. By selectively causing the array of light emitting elements 50B to emit light, blue light is incident on the photoreceptor 1, and the light emitting elements 50
By causing the array of G to emit light, green light is incident, and by causing the array of light emitting elements 50R to emit light, red light is incident. By causing all the light emitting elements 50B, 50G, and 50R to emit light, light having the same components as white light having blue, green, and red components can be incident on the photoreceptor 1. This is also used when forming a monochrome image.

Lighting control of each light emitting element is performed in the same manner as X' when driving a DAP type cell.

By using the above uniform exposure devices as the uniform exposure devices 5B, 5G, and 5R, the uniform exposure devices 5B, 5G, and
By switching the SR so that blue, green, and light from the outside are incident on the photoreceptor 1, the image on the original O can be easily color-converted without replacing the developing units 6Y, 6M, 6C, etc. Color images can be formed clearly without color shift.

In the image forming apparatus of the present invention, B and G of the photoreceptor 1.

Color information formed on each R filter section and having a complementary color relationship with the filter color is developed with toner of a color other than the complementary color to perform color conversion. For example, yellow information formed on the B filter section is developed with a cyan or magenta toner other than yellow, and magenta information formed on the G filter section is developed with a yellow or cyan toner other than magenta, and then formed on the R filter section. Cyan information is developed with yellow or magenta toner other than cyan. However, it is not limited to this. That is, it is not necessary to perform color conversion between all developers and filters, and the number changes depending on the color to be converted.

When the uniform exposure devices 5B, -5G, and 5R input light having blue, green, and red components, the image density and resolution are the same as in a monochrome copying machine or the like in which the photoreceptor 1 does not have a color separation function. It is possible to form a monochromatic image consisting of yellow, magenta, cyan, etc. toner. Furthermore, when the uniform exposure device shown in FIG. 7 uses an array of light emitting elements 50B, 50G, and 50R, the uniform exposure range is limited to the image forming area, and toner is not applied to the non-image area. It is possible to easily prevent an adhering potential pattern from occurring, thereby preventing the occurrence of black frames and waste of toner. Light emitting elements 50B, 50G that emit specific light,
Instead of 50R, a combination of a light emitting element that emits panchromatic light and a solid or liquid crystal filter may be used.

If the uniform exposure range is not changed, the light emitting elements do not need to have an array configuration.

Further, the image forming apparatus of the present invention is not limited to one that forms a color image using yellow, magenta, and cyan toner.
For example, it may form a color image using red, green, and blue toners, it may also include a developing device containing black toner, and it may form a four-color color image, or it may have only two developing devices. It may be something that doesn't exist.

Furthermore, the present invention provides an image forming apparatus that repeats charging for smoothing, whole surface exposure with specific light, and development after secondary charging, secondary charging, and image exposure, as described in Japanese Patent Application No. 60-229524. It can also be applied to

In addition, a configuration in which the photoreceptor is provided with a filter on the side opposite to the side receiving corona discharge from a charger or the like and receives image exposure and uniform exposure from the filter side (Japanese Patent Application No. 59-199547) and other configurations (Patent Application Showa 59-198166゜198167
, 201084). In addition, the photoconductive layer of the photoreceptor is not a single layer, but has a functionally separated structure consisting of a charge generation layer and a charge transfer layer (Japanese Patent Application No. 60-22952
No. 4, No. 60-245178), or one in which the photoconductor has a color separation function in the photoconductive layer (Japanese Patent Application No. 59-2
No. 01085, No. 60-245177).

Further, specific examples of the present invention will be shown below.

Example 1: U-B manufactured by Konishiroku Photo Industry Co., Ltd. was used in the image forming apparatus shown in FIG.
ix 3300 MR was used. The photoreceptor had the layer structure shown in FIG. 2, and Nj was used for the conductive substrate 1a to facilitate charge injection during primary charging. Insulating surface layer 1
For d, a 25 μm thick polyethylene terephthalate thin film with a filter pattern as shown in FIG. 4 was printed on a 20 μm thick polyethylene terephthalate thin film. 2 Te is added to the photoconductor layer 1b.
A 5% doped Se Te photoconductor was used.

The outer diameter of the photoreceptor drum is φ12ON, and the linear speed is 92sn/
sec.

The uniform exposure devices 5B, 5G, and 5R are D as shown in FIG.
It consisted of an AP type liquid crystal cell and a white fluorescent lamp.

For normal color image formation, a voltage V is applied to the 51R portion of the DAP type liquid crystal cell of the -il exposure device 5B.

Similarly, a voltage V3 was applied to the portion 51B of the DAP type liquid crystal cell of the uniform exposure device 5R to form an image.

The relationship between the color information and the toner image when color conversion is performed and when it is not performed is shown below.

Example 2゜The same image forming apparatus as in Example 1, with uniform exposure device 5B D
Apply voltage ■8 to the 51R section of the AP type liquid crystal cell, similarly apply the voltage ■ to the 51B section of the DAP type liquid crystal cell of the uniform exposure device 5G, and apply the voltage ■ to the 51G section of the 5R DAP type liquid crystal cell. 6 was applied to perform image formation.

The relationship between the color information and the toner image when color conversion is performed and when it is not performed is shown below.

〔Effect of the invention〕

According to the image forming apparatus of the present invention, it is possible to clearly reproduce a document image without any color shift, and it is possible to easily form a color-converted image of the document image clearly without color shift, without replacing the developing device or the like. Moreover, the advantageous effect of being able to form a monochrome image with the same image density and resolution as in a monochrome copying machine or the like can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of the configuration of an example of the image forming apparatus of the present invention, and FIG. 2 is a partial cross-sectional view of an example of the N configuration of the photoreceptor.
3 and 4 are partial plan views showing an example of the filter distribution shape of the color separation layer of the photoconductor, FIG. 5 is a potential change chart on the surface of the photoconductor in the color image forming process, and FIGS. 6 and 7 Each figure is a schematic front view showing an example of a specific light uniform exposure device used in the image forming apparatus of the present invention. l...photoreceptor, 1a...conductive substrate,
1b... Optical electrical conductor layer, lc... Color separation layer, 1d
...Insulating surface layer, le...Protective layer, 2.4,
7Y, 7M... Charger, 3... Image exposure device, 5B, 5G, 5R... Uniform exposure device for specific light, 50.
...Cold cathode discharge tube, 50B, 50G, 50R...Light emitting element, 51...Liquid crystal cell, 51B, 51G, 51R...Composite cell, 52...Common substrate, 6Y, 6M, 6C,...Developer, 8...Transfer pre-processing device, 9...Transfer device, 10...
- Separator, 11... Pre-cleaning static eliminator, 12... Cleaning device. Patent applicant: Konishiroku Photo Industry Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 4

Claims (3)

[Claims] (1) Using a photoreceptor with a color separation function, after forming a primary latent image by charging and imagewise exposing the photoreceptor, uniformity of specific light to draw a color-separated electrostatic image from the primary latent image. In an apparatus that repeatedly performs exposure and development of the electrostatic image to form a color image consisting of a composite of a plurality of color toner images on a photoreceptor,
A photoconductor having a color separation function, characterized in that each uniform exposure device that uniformly exposes the specific light uses a uniform exposure device that can switch any specific light to enter the photoconductor. An image forming device using (2) A claim in which the uniform exposure device is a combination of a light source that emits panchromatic light and a filter using a liquid crystal cell that can selectively transmit any of the specific lights from the light. An image forming apparatus using a photoreceptor having a color separation function according to item 1. (3) The color according to claim 1, wherein the uniform exposure device is configured to include an array of light emitting elements that emit each specific light, and to selectively cause any of the light emitting elements of the specific light to emit light. An image forming device that uses a photoreceptor that has a decomposition function.