JP2000275885A - Electrophotographic photoreceptor and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a phenomenon that a transferred image becomes blur when an amorphous silicon photoreceptive layer is used in an inside exposing system electrophotographic photoreceptor and an electrophotographic device using the same. SOLUTION: As to this electrophotographic device having the electrophotographic photoreceptor 10 having the photoreceptive layer constituted of a photoconductive material, and an electrifying device 31 electrifying the photoreceptor 10, and an exposing device 32 irradiating the electrified sensitive body 10 with light and forming an electrostatic latent image on one surface side of a light-transmissive base body; the device 31 is arranged on a side where the photoreceptive layer is formed, the device 32 is arranged on a side where the photoreceptive layer of the photoreceptor 10 is not formed, and a light- transmissive heater layer 20 positioned between the photoreceptive layer and the device 32 is provided on the photoreceptor 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming an electrostatic charge image (hereinafter referred to as an electrostatic latent image) on a photoreceptor by utilizing a photoconductive phenomenon, and further, to a colored charged fine particle (toner). And an electrophotographic apparatus using an electrophotographic process for obtaining a visible image by electrostatically adhering an electrostatic latent image to an electrostatic latent image, and an electrophotographic photosensitive member used for the electrophotographic apparatus.
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoconductor of an internal exposure type electrophotographic apparatus in which an exposure device is disposed on a substrate side of a photoconductor such as a method (PhotoInduced Toning Electrophotography).

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic apparatus using an electrophotographic process, a copying machine using a PPC (Plain Paper Copy) method for transferring a toner image formed on a photoreceptor onto paper or the like has been put into practical use. The so-called Carlson method is generally used. FIG. 5 schematically shows an electrophotographic process using the Carlson method, and reference numeral 60 denotes an electrophotographic apparatus. In a dark place, the surface of the photoconductor 50 is uniformly charged by the charger 61. Next, the exposing device 62 irradiates light to a portion other than the image portion, removes the charged charge in the portion to which the light is applied, and forms an electrostatic latent image on the photoconductor 50 with the charge remaining in the image portion. Next, toner charged to a polarity opposite to that of the electrostatic latent image by the developing device 63 is attached to the latent image to form a visible image, and this is transferred to the paper 40 by the transfer device 64. The paper 40 to which the toner has been transferred is heated or pressurized by a fixing device 67 to form a paper 4.
The toner is fused to 0 to form an image. On the other hand, the photoreceptor 50 after the transfer is neutralized by irradiating light with a static eliminator 65 and then cleaned by a cleaner 66 to repeat a series of electrophotographic processes.

As the photoconductor 50, a selenium photoconductor, an organic photoconductor (OPC) photoconductor, an amorphous silicon photoconductor, or the like is generally used. FIG. 6 is a cross-sectional view showing an example of the amorphous silicon photoconductor 50, in which a photoconductor layer 56 is formed on an aluminum substrate 51 formed in a cylindrical shape. The photoreceptor layer 56 includes, in order from the substrate side, a blocking layer 53 for preventing injection of carriers from the substrate, an amorphous silicon photosensitive layer 54 for retaining charges and absorbing exposed light to generate carriers, and a photosensitive layer 54. It consists of a surface protection layer 55 for protection.

In recent years, the miniaturization of copiers has further progressed, and there has been a demand for the development of electrophotographic processes capable of miniaturization.
PITE method (Photo Induced Toning Electrophotograph
Attention has been paid to a process of providing an exposure device 62 such as y) on the inner surface of the photoconductor 50. This method is called an inner surface exposure method or the like, in which an exposure device 62 is provided inside the photoconductor 50, that is, on the substrate 51 side, and the photoconductor layer 56 from the inner surface side to the outer surface side of the photoconductor 50 is exposed. It is. Therefore, the base 5
As 1, a light-transmitting material such as glass or plastic is used. With such a structure, the exposure device can be arranged on the inner surface of the photoconductor, and the size can be reduced.

[0005]

When an amorphous silicon photosensitive layer is used as the photosensitive layer of the above-mentioned inner surface exposure type photosensitive body, a phenomenon in which an image transferred to paper is blurred due to long use is observed. Was done.

[0006] After examining the cause, the photoreceptor 50 using the amorphous silicon photosensitive layer was exposed to nitrogen oxides due to the effects of ozone and the like generated in the electrophotographic process due to the use of the charger 61 as a result of prolonged use. (NO
x) occurs in the electrophotographic process, and nitrogen oxides and the like adhere and adsorb to the surface of the photoreceptor layer, a deteriorated layer is formed on the surface, and a certain thin film is formed on the surface of the photoreceptor 50 It seems to be the cause. Since the surface thin film has a lower resistance than the photoconductor layer, the charge of the photoconductor layer 56 flows toward the surface of the photoconductor 50, and as a result, the electrostatic latent image becomes blurred. It is considered that the transferred image was blurred, that is, a phenomenon of image deletion was caused.

In order to prevent image deletion, it is necessary to make it difficult for nitrogen oxides or the like to adhere to the surface of the photoreceptor 50, or
It is conceivable that even if the surface thin film layer is formed, it is removed in a subsequent cleaning step or the like. In the case of the amorphous silicon photoconductor, it is difficult to remove the surface thin film layer in the cleaning process because the photoconductor layer 56 is hard,
It was effective to employ a method of heating the photoreceptor 70 to make it less likely to adhere to the surface.

However, in an electrophotographic process of exposing from the substrate side using a translucent substrate as in the case of the inner surface exposure method, it is necessary to provide an exposing device on the inner surface side of the photoreceptor 70. It is difficult to provide a heater close to the body 70, and it is also difficult to heat the entire photoreceptor process. Therefore, when the heater is provided, there is a problem that the apparatus becomes large and effective heating cannot be performed.

In view of the above, it is an object of the present invention to provide an electrophotographic photoreceptor capable of effectively heating a photoreceptor of an internal exposure type and achieving downsizing, and an electrophotographic apparatus using the photoreceptor. And

[0010]

According to an aspect of the present invention,
An electrophotographic photosensitive member having a photosensitive layer made of a photoconductive material on one surface side of a light-transmitting substrate; a charger for charging the photosensitive member; and an electrostatic latent image formed by irradiating the charged photosensitive member with light. And an exposing device for forming an electrophotographic device, wherein the charging device is disposed on a side on which the photosensitive layer is formed, and the exposing device is disposed on a side of the photoconductor on which the photosensitive layer is not formed. The photoreceptor is an electrophotographic apparatus of an internal exposure type having a light-transmitting heater layer located between the photosensitive layer and the exposure device, and a photoreceptor provided with the light-transmitting heater layer is provided.

Since the light-transmitting heater layer is formed on the photosensitive member, a small-sized electrophotographic photosensitive member capable of effectively heating the photosensitive member without obstructing the optical path of the exposure device even in an electrophotographic apparatus of an internal exposure type. A body and an apparatus using the photoreceptor are provided, and the above object is achieved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 1 shows an example of a schematic configuration of an electrophotographic apparatus 30 of the inner surface exposure type according to the present invention, and FIG. 2 shows an example of a photoconductor 10 used in the electrophotographic apparatus 30. After uniformly charging the surface of the photoreceptor 10 with the charger 31 in a dark place,
The exposing unit 32 irradiates the image area with light, removes the charged electric charge in the light-irradiated area, and forms an electrostatic latent image on the photoreceptor 10 with the electric charge remaining in places other than the image area. Next, the developing device 33
The toner charged to the same polarity as the electrostatic latent image is attached to the latent image to form a visible image, which is transferred to paper 40 by the transfer unit 34. The paper 40 to which the toner has been transferred is heated or pressed by a fixing device 37 to fuse the toner to the paper 40 to form an image. On the other hand, the photoreceptor 10 after the transfer is used as the neutralizer 35.
After the electricity is removed by irradiating light at
And a series of electrophotographic processes is repeated. The series of processes is the same as in the conventional case.

In the present invention, unlike the prior art, an exposure device 32 such as an LED array
Is provided, and a heater layer 20 for adjusting the temperature is provided between the exposure device and the photoconductor layer 16. The heater layer 20 is connected to a temperature control unit (not shown) to control the temperature to an appropriate temperature.

Next, specific preferred examples of the photoreceptor will be described along the manufacturing method, and an electrophotographic apparatus using the photoreceptor will be described.

(Embodiment 1) As shown in FIG. 2, the photoreceptor 10 has a blocking layer 13, an amorphous silicon photoreceptor layer 14, and an amorphous silicon photoreceptor layer 14 on a transparent substrate 11 having an outer surface provided with a ground electrode layer 12. It has an amorphous silicon photoreceptor layer 16 on which a surface protection layer 15 is laminated, and a heater layer 20 is provided inside the base.

The photosensitive member 10 is manufactured, for example, as follows. 1.5 mm thick cylindrical glass substrate 11
And heated to about 600 ° C, then tin (Sn)
An antimony (Sb) -based metal chloride solution is sprayed on the inner surface and the outer surface of the glass substrate 11 by spraying or the like. The metal chloride solution that hit the high temperature glass surface is
Then, the conductive light-transmitting metal oxide film in which antimony is added to tin oxide is formed by decomposition and oxidation. In this manner, the heater layer 20 is provided on the inner side of the
The ground electrode layer 12 was simultaneously provided on the outer surface side of.

Next, the transparent substrate 11 on which the transparent metal oxide film is formed is set in a plasma CVD apparatus.
Thereafter, the substrate 11 is heated to a temperature of 250 to 300 ° C,
SiH ₄ , B ₂ H ₆ , H at a vacuum of 0.5 to 5 Torr
13.56 by introducing a material gas such as ₂ , CH ₄ , and N _2.
A high-frequency power of MHz was applied to continuously form a blocking layer 13, an amorphous silicon photosensitive layer 14, and a surface protective layer 15 to form a photoreceptor layer 16, thereby producing a photoreceptor 10 for electrophotography. The thickness of each layer of the photoconductor layer 16 is 3 μm, 25 μm, and 0.3 μm, respectively.

The photosensitive member 10 manufactured in the above embodiment is shown in FIG.
Used in the electrophotographic apparatus 30 shown in FIG. At this time, when the temperature of the photoconductor 10 was controlled to about 40 ° C. by the heater layer 20, the amorphous silicon photoconductor layer 1 was controlled.
The adhesion of nitrogen oxides and the like to the surface of No. 6 was reduced, and image deletion was less likely to occur.

The photosensitive wavelength range of the amorphous silicon photoreceptor is about 400 to 800 nm, and it is desirable that the wavelength of the light source of the exposure device also coincides with this photosensitive wavelength range. An earth electrode layer 12 provided on the photoconductor 10 and a heater layer 2
0 preferably indicates a high transmittance in both wavelength ranges. Specifically, when the transmittance is 50% or more, preferably 70% or more when provided on a glass substrate in a region of 400 to 800 nm. good. The sheet resistance of the heater layer 20 is preferably 1 Ω / sq to 100 KΩ / sq,
More preferably, it has a characteristic of 10 Ω / sq to 10 KΩ / sq, and is preferably formed by a wet film formation method.

Example 2 FIG. 3 shows a photoreceptor 21 of another embodiment. The heater layer 20 is formed on the glass substrate 11 as in the first embodiment. However, in the first embodiment, the heater layer 20 is provided on the inner surface side of the base 11;
In FIG. 3, it is formed on the outer surface of the glass substrate 11 as shown in FIG. Further, an SiO ₂ insulating layer 17 having a thickness of 0.1 μm and a ground electrode layer 12 having a thickness of 1 μm were formed thereon by a coating method or the like. Using this substrate, a photoreceptor layer 16 was formed in the same procedure and under the same conditions as in Example 1.

The ground electrode layer 12 has a thickness of 10 MΩ / sq.
The following sheet resistivity is preferable. In the case of an amorphous silicon photoreceptor, if the sheet resistance is higher than that, it is difficult to discharge electric charges during operation of the photoreceptor, which is not preferable.

This photosensitive member 21 is used in an electrophotographic apparatus 30 in the same manner as in the previous embodiment, and about 4
When the image was transferred by heating to 0 ° C., the image was not blurred even when the durability test was performed for the same time as in the conventional example. In addition, when the heating temperature was examined,
The range of 5 ° C. was the effective temperature range.

(Embodiment 3) FIG. 4 shows a photosensitive member 22 according to still another embodiment. Also in this embodiment, the heater layer 20 is formed on the glass substrate 11, and the photoconductor layer 16 is formed thereon under the same procedure and the same conditions as those of the first embodiment. However, in this embodiment, the heater layer 20 has both a function as a heater for heating the photoconductor 22 without providing the ground electrode layer and a function as an earth electrode layer for releasing electric charge when the photoconductor operates. . Therefore, the number of steps can be reduced, and the cost can be reduced, as compared with the case where the electrodes are separately formed as in the second embodiment.

This photosensitive member 22 is also used in the electrophotographic apparatus 30 in the same manner as in the previous embodiment, and the heater layer 20 is used.
Was heated to form an image, but the image was not blurred even after the durability test for the same time as in the conventional example.

In the above-described embodiment, an example of the photoconductor having the amorphous silicon photoconductor layer 16 is described. However, the present invention can be applied to any photoconductor having a photoconductor layer containing silicon as a main component. In addition, Se _{2 in which} the phenomenon of image deletion occurs
The as ₃ photoconductor silicon, etc. it can be applied in the case of using a photosensitive member which is not a main component. Further, the shape of the photoreceptor is not limited to the cylindrical shape described above, but may be a belt-like shape using a polymer film or the like as a light-transmitting substrate.

In the case of the inner surface exposure method, it is necessary to provide an exposure device on the side of the photoreceptor substrate, and to precisely focus the exposure device on the photosensitive layer. Therefore, in an electrophotographic apparatus using an amorphous silicon photoreceptor having a long printing life of the photoreceptor, the image can be prevented from flowing and the life can be further prolonged. This makes it unnecessary to perform the above-mentioned focusing operation caused by the exchange of the photoconductor, and provides an extremely excellent effect in practical use that an electrophotographic apparatus with almost no exchange of the photoconductor can be provided. Therefore, overall cost reduction can be achieved,
It is particularly suitable for an electrophotography of an inner surface exposure method using an amorphous silicon photoreceptor.

[0028]

As described above, according to the present invention, in the electrophotographic apparatus of the inner surface exposure type, the photoreceptor is provided with the light-transmitting heater layer which does not hinder the exposure. In particular, when an amorphous silicon photosensitive member is used, an excellent effect that an image flow is prevented and a longer life can be achieved can be achieved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an electrophotographic apparatus of an inner surface exposure type according to the present invention.

FIG. 2 is a cross-sectional view of a main part showing the electrophotographic photosensitive member of the present invention.

FIG. 3 is a sectional view of a main part showing an electrophotographic photoreceptor of another embodiment.

FIG. 4 is a cross-sectional view illustrating a main part of an electrophotographic photosensitive member according to still another embodiment.

FIG. 5 is a schematic configuration diagram illustrating an electrophotographic apparatus according to the Carlson method.

FIG. 6 is a sectional view of a main part showing a conventional electrophotographic photosensitive member.

[Explanation of symbols]

10, 21, 22, 50 Electrophotographic photoreceptor 11, 51 Base 12 Ground electrode layer 13, 53 Blocking layer 14, 54 Amorphous silicon photosensitive layer 15, 55 Surface protective layer 16, 56 Amorphous silicon photosensitive layer 17 Insulating layer 20 Heater Layer 30, 60 Electrophotographic device 31, 61 Charger 32, 62 Exposure device 33, 63 Developing device 34, 64 Transfer device 35, 65 Static eliminator 36, 66 Cleaner 37, 67 Fixing device 40 Paper

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G03G 21/00 350 G03G 15/12

Claims (6)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer made of a photoconductive material on one surface side of a translucent substrate, a charger for charging the photosensitive member, and irradiating the charged photosensitive member with light. An exposing device that forms an electrostatic latent image by exposure, wherein the charging device is disposed on a side on which the photosensitive layer is formed, and the exposing device forms a photosensitive layer of the photoconductor. An inner surface exposure type electrophotographic apparatus, wherein a light-transmitting heater layer is provided between the photosensitive layer and the exposing device on the photosensitive member. 2. The electrophotographic apparatus according to claim 1, wherein said photosensitive layer contains amorphous silicon as a main component. 3. The heater layer according to claim 2, wherein the heater layer is formed on the surface of the light-transmitting substrate, and has a transmittance of 50% or more in a wavelength range of 400 nm to 800 nm.
2. The electrophotographic apparatus according to claim 1. 4. The photosensitive layer according to claim 1, wherein the photosensitive layer is formed on a heater layer provided on a light-transmitting substrate, and charges charged on the photosensitive member are released through the heater layer. Item 3. An electrophotographic apparatus according to Item 2. 5. The electrophotographic photoreceptor used in the electrophotographic apparatus according to claim 1, wherein the light-transmitting substrate has a light-transmitting conductive layer formed on both surface sides. The light-transmitting conductive layer provided on one surface side serves as an earth electrode layer for discharging charges charged by the photosensitive layer formed on the layer, and the light-transmitting conductive layer provided on the other surface side. An electrophotographic photosensitive member, wherein the layer is the heater layer. 6. The electrophotographic photosensitive member used in the electrophotographic apparatus according to claim 1, wherein a heater layer, an insulating layer,
An electrophotographic photoreceptor comprising a ground electrode layer formed in order, and a photosensitive layer provided thereon.