JPS639221B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention utilizes electromagnetic waves such as light (here, light in a broad sense, including ultraviolet rays, visible rays, infrared rays, X-rays, γ-rays, α-rays, etc.). The present invention relates to electrophotographic imaging members used to form images.

Conventionally, photoconductive materials constituting the photoconductive layer of electrophotographic image forming members include inorganic photoconductive materials such as Se, CdS, and ZnO, poly-N-vinylcarbazole (PVK), and trinitrofluorenone (TNF). Organic photoconductive materials (OPCs) are commonly used.

However, in electrophotographic image forming members using these photoconductive materials, there are still various issues that can be resolved, and the conditions may be relaxed to a certain extent to suit individual circumstances. In reality, each suitable electrophotographic imaging member is used.

For example, in an electrophotographic image forming member using Se as a photoconductive layer-forming material, Se alone has a narrow spectral sensitivity range when using light in the visible light region, so Te or As is added to produce a spectral sensitivity. The aim is to expand the sensitivity range.

However, although electrophotographic image forming members having such Se-based photoconductive layers containing Te and As certainly improve the spectral sensitivity range, optical fatigue increases, making it difficult to print the same original. Continuously copying may result in a decrease in the image density of the copied image or background stains (fogging on white areas), and if you continue to copy other documents, the image of the previous document may be copied as an afterimage ( It has drawbacks such as ghost development).

However, since Se, especially As and Te, are extremely harmful substances to the human body, it is necessary to devise ways to use manufacturing equipment that does not come into contact with the human body during manufacturing. The capital investment is significantly large. Furthermore, if the photoconductive layer is exposed even after manufacturing, the surface of the photoconductive layer will be directly rubbed during cleaning and other treatments, and a portion of it will be scraped off, preventing development. They may get mixed into agents, be scattered inside copying machines, or be mixed into copied images, resulting in contact with the human body. Furthermore, when the surface of a Se-based photoconductive layer is continuously and repeatedly exposed to corona discharge many times, crystallization or oxidation occurs near the surface of the layer, leading to deterioration of the electrical properties of the photoconductive layer. There are many cases. Alternatively, if the surface of the photoconductive layer is exposed, when a liquid developer is used to visualize (develop) an electrostatic image, it will come into contact with the solvent, resulting in poor solvent resistance (liquid development resistance). Although excellent properties are required, it is difficult to say with certainty that Se-based photoconductive layers are necessarily satisfactory in this respect.

In order to improve these points, it has been proposed to cover the surface of the Se-based photoconductive layer with a surface coating layer called a so-called protective layer, an electrically insulating layer, or the like.

However, with regard to these improvements, there still remains a sufficient solution in terms of adhesion and electrical contact between the photoconductive layer and the surface coating layer, as well as the electrical properties and surface properties required of the surface coating layer. At present, it is difficult to say that this has been achieved.

Separately, since the Se-based photoconductive layer is usually formed by vacuum evaporation, it requires a significant capital investment in equipment for this purpose, and it is difficult to form a photoconductive layer with desired photoconductive properties. To obtain layers with good reproducibility,
Various manufacturing parameters such as evaporation temperature, evaporation substrate temperature, degree of vacuum, and cooling rate must be precisely adjusted.

Furthermore, the surface coating layer can be formed by laminating a film-like material onto the surface of the photoconductive layer via an adhesive, or
Because it is formed by applying a surface coating layer forming material,
It is necessary to install equipment separate from the equipment for forming the photoconductive layer, and there is a significant increase in capital investment.
This is extremely unfavorable in the current period of slow economic growth.

In addition, the Se-based photoconductive layer is formed in an amorphous state in order to maintain high dark resistance as a photoconductive layer of an electrophotographic image forming member, but Se crystallization occurs at an extremely low temperature of approximately 65°C. Because of this, crystallization occurs during handling after manufacturing, or due to the influence of frictional heat caused by rubbing against other parts during the ambient temperature and image forming process during use. However, it also has a drawback in terms of heat resistance, in that it tends to cause a decrease in dark resistance.

On the other hand, electrophotographic imaging members that use ZnO, CdS, etc. as photoconductive layer constituent materials have a photoconductive layer in which particles of the photoconductive material such as ZnO or CdS are uniformly dispersed in a suitable resin binder. It is formed by This image-forming member having a so-called binder-based photoconductive layer is advantageous in manufacturing compared to an image-forming member having an Se-based photoconductive layer, and can be manufactured at a relatively low manufacturing cost. That is, the binder-based photoconductive layer is prepared by applying a coating solution prepared by kneading ZnO or CdS particles and a suitable resin binder using a suitable solvent onto a suitable substrate using a doctor blade method, dipping method, etc. Since it can be formed simply by coating and solidifying using the coating method of It is simple and easy.

However, the binder-based photoconductive layer is basically a two-component system consisting of a photoconductive material and a resin binder, and the photoconductive material particles are uniformly dispersed in the resin binder. Due to the specific nature of the formation, there are many parameters that determine the electrical and photoconductive properties as well as the physical and chemical properties of the photoconductive layer, and therefore, these parameters must be precisely adjusted to achieve the desired results. There is a drawback that a photoconductive layer having specific characteristics cannot be formed with good reproducibility, leading to a decrease in yield and a lack of mass productivity.

Furthermore, due to the unique nature of the binder-based photoconductive layer being a dispersed system, the entire layer is porous, and as a result, it is highly dependent on humidity, resulting in deterioration of electrical properties when used in a humid atmosphere. In many cases, it becomes impossible to obtain a copy of the image.

Furthermore, the porous nature of the photoconductive layer causes developer to enter the layer during development, which not only reduces mold releasability and cleaning properties but also makes it unusable. When a developer is used, the above point becomes significant because the developer penetrates into the layer along with its carrier solvent under the acceleration of capillary development, and as in the case of the Se-based photoconductive layer, the surface of the photoconductive layer is It is necessary to cover with a covering layer.

However, even with this improvement by providing a surface coating layer, the surface of the photoconductive layer is uneven due to the porous nature of the photoconductive layer, so the interface is not uniform and the adhesion between the photoconductive layer and the surface coating layer is poor. Another disadvantage is that it is difficult to obtain good electrical contact.

In addition, when using CdS, since CdS itself has an effect on the human body, care must be taken to prevent it from coming into contact with the human body or scattering into the surrounding environment during manufacturing and use. It is necessary to
When using ZnO, there is almost no effect on the human body, but ZnO binder-based photoconductive layers have drawbacks such as low photosensitivity, narrow spectral sensitivity range, significant optical fatigue, and poor photoresponsiveness. ing.

In addition, in electrophotographic image forming members using organic photoconductive materials such as PVK and TNF, which have recently been attracting attention, PVK, TNF, etc. This method has the advantage in manufacturing that a photoconductive layer can be formed simply by forming a coating film of an organic photoconductive material, and the advantage that an electrophotographic image forming member with excellent flexibility can be manufactured. On the other hand, it has drawbacks such as lacking moisture resistance, corona ion resistance, and cleaning properties, and low photosensitivity, and the spectral sensitivity range in the visible light region is narrow and biased toward short wavelengths. , it is used only in a very limited range. However, there is no guarantee that many of these organic photoconductive materials are completely harmless to the human body, such as some containing carcinogenic substances.

As described above, electrophotographic image forming members using photoconductive materials, which have been pointed out as materials for forming the photoconductive layer of electrophotographic image forming members, have both advantages and disadvantages, so there are some difficulties in manufacturing them. At present, the conditions and usage conditions are relaxed, and an appropriate electrophotographic image forming member suitable for each use is selected and put into practical use.

Therefore, the third material for forming the photoconductive layer of an electrophotographic image forming member that can provide an excellent electrophotographic image forming member in which the above-mentioned problems are solved.
materials are desired.

Such materials that have recently been viewed as promising include amorphous silicon containing 1 to 40 atomic percent hydrogen (hereinafter abbreviated as a-Si:H) and amorphous germanium containing hydrogen (hereinafter a-Si:H).
Ge: abbreviated as H).

a-Si:H and a-Ge:H meet the requirements for photoconductive layers of electrophotographic image forming members, such as photosensitivity, corona ion resistance, solvent resistance, light fatigue resistance, moisture resistance, and heat resistance. In terms of durability, abrasion resistance, cleanability, etc., it has properties that are comparable to those of conventional electrophotographic image forming materials. However, for example, the a-
Research and development efforts have been focused on Si:H films mainly for application to solar cells, so the dark resistance is 10 ⁵ to 10 ⁸ Ω・cm.
Even if an attempt is made to apply it as it is as a photoconductive layer of an electrophotographic image forming member, the dark resistance is too close and it cannot be used at all in currently known electrophotographic methods. This problem of dark resistance can be said similarly for a-Ge:H.

The present invention can be used as a photoconductive layer of an electrophotographic image forming member while maintaining the high photosensitivity, corona ion resistance, moisture resistance, abrasion resistance, and cleaning properties of a-Si:H and a-Ge:H. This solution solves the problem of dark resistance so that it can be applied.

In the present invention, since the device can be easily made into a closed system during manufacturing, it is possible to avoid adverse effects on the human body. is non-polluting, has no impact on the natural environment, has excellent heat resistance and moisture resistance, always has stable electrophotographic properties, and is suitable for all environments with almost no restrictions on usage environments. The main object of the present invention is to provide an electrophotographic image forming member that has excellent light fatigue resistance and corona ion resistance, and does not cause deterioration even after repeated use.

Another object of the present invention is to provide an electrophotographic image forming member that can easily produce high-quality images with high density, clear halftones, and high resolution.

Another object of the present invention is that the dark resistance and photosensitivity are high, the spectral sensitivity range covers almost the entire visible light range, the dark decay rate is small, and the photoresponsiveness is fast.
Another object of the present invention is to provide an electrophotographic image forming member that has excellent abrasion resistance, cleaning properties, and solvent resistance.

The initial object of the present invention was to form a lower layer of amorphous silicon or/and germanium containing hydrogen, and a layer of 0.1 to 10 μm consisting of amorphous silicon or/and germanium containing 0.1 to 30 atomic percent oxygen together with hydrogen. This is accomplished by forming a photoconductive layer consisting of a thick top layer.

The most typical structural example of the electrophotographic image forming member of the present invention is shown in FIGS. 1 and 2. The electrophotographic imaging member 1 shown in FIG. 1 includes a support 2,
The lower layer 3 of the photoconductive layer is composed of a lower layer 3 of the photoconductive layer and an upper layer 4 of the photoconductive layer, and the lower layer 3 of the photoconductive layer is a-Si:H or/and a
-Ge:H, and the upper layer 4 of the photoconductive layer is formed of a-Si:H or/and a-Ge:H containing oxygen.

As mentioned above, normal a-Si:H or/and A-
By laminating the upper layer 4 of the photoconductive layer made of a-Si:H or/and a-Ge:H containing oxygen on the lower layer 3 of the photoconductive layer made of Ge:H, the dark resistance can be reduced. It is possible to achieve a remarkable increase in photosensitivity and a high photosensitivity, resulting in a photoconductive layer having electrophotographic properties that are comparable to those of conventional Se-based photoconductive layers.

For example, in the glow discharge method, the a-Si:H or/and A-Ge:H used as the lower layer 3 of the photoconductive layer is a hydride such as SiH ₄ , Si ₂ H ₆ , GeH ₄ as it is,
Alternatively, using these gases diluted with Ar, _H2, etc., the material is decomposed and deposited by glow discharge. For example, when using the sputtering method, Si or Ge or (Si+Ge) is used as the target,
Sputtering is performed in a mixed gas atmosphere of inert gas such as Ar and _H2 .

A- containing oxygen used as the upper layer 4 of the photoconductive layer
For example, in the glow discharge method, Si:H and/or a-Ge:H are used as hydrides such as SiH ₄ , Si ₂ H ₆ , GeH ₄ as they are, or with these gases diluted with Ar, H ₂ , etc. , O ₂ or a gas obtained by diluting O ₂ with an inert gas such as Ar are introduced into the vapor deposition tank from separate inlets,
It is decomposed and deposited by glow discharge. For example, when using the sputtering method, Si, Ge, or (Si+Ge) is used as the target, and H ₂ is
Sputtering is performed by introducing a gas diluted with an inert gas such as Ar and a gas obtained by diluting O ₂ with an inert gas such as Ar into the vapor deposition tank from separate inlets.

The amount of oxygen contained in the upper layer 4 of the photoconductive layer must be appropriately determined depending on the characteristics of the lower layer 3 of the photoconductive layer, but is usually 0.1 to 30 atomic%, preferably 0.1 to 10 atomic%. is desirable. or,
The thickness of the upper layer 4 of the photoconductive layer is usually 0.1 to 10 μm, preferably 0.5 to 5 μm, in order to effectively increase the dark resistance without impairing the characteristics of the lower photoconductive layer 3. .

The support 2 may be electrically conductive or electrically insulating. Examples of the conductive support include stainless steel, Al, Cr, Mo, Au, Ir, Nb, Te,
Examples include metals such as V, Ti, Pt, and Pd, and alloys thereof. As the electrically insulating support, films or sheets of synthetic resins such as polyester, polyethylene, polycarbonate, cellulose triacetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, glass, ceramic, paper, etc. are usually used. . It is desirable that at least one surface of these electrically insulating supports is electrically conductive treated.

For example, if it is glass, its surface is conductive treated with In ₂ O ₃ or SnO ₂ , or if it is a synthetic resin film such as polyester film, it is treated with Al, Ag,
Pb, Zn, Ni, Au, Cr, Mo, Ir, Nb, Ta, V,
Vacuum evaporation, electron beam evaporation with metals such as Ti and Pt,
The surface is made conductive by sputtering or by laminating with the metal. The shape of the support may be any shape, such as a cylinder, a belt, or a plate, and the shape is determined depending on the need. In the case of continuous high-speed copying, an endless belt or a cylindrical shape is used. It is desirable to do so. The thickness of the support is determined appropriately so that the desired image forming member is formed, but when flexibility is required as an image forming member, the support function can be fully demonstrated. Within this range, it is made as thin as possible. However, in such cases, from the viewpoint of manufacturing and handling of the support, mechanical strength, etc., it is usually 10μ.
This is considered to be the above.

The electrophotographic image forming member 5 shown in FIG. 2 has a charge injection function that serves to prevent carrier from entering the lower layer 8 of the photoconductive layer from the side of the support 6 during charging processing during electrostatic image formation. A blocking layer 7 is provided. This is intended to further improve the charging potential and reduce dark decay. Materials for forming such a charge injection blocking layer 7 include Al ₂ O ₃ , SiO,
Examples include inorganic insulating compounds such as SiO ₂ and organic insulating resins such as polyethylene, polycarbonate, polyurethane, and polyparaxylylene. In addition, when the electrophotographic image forming member 5 is used with positive charging, P-type doped A-Si:H or/and a
-Ge:H, n-type doped A-Si:H or/and a-Ge:
H is effectively used.

The method for forming the charge injection blocking layer 7 differs depending on the material, but for example, inorganic insulating compounds such as Al ₂ O ₃ , SiO, SiO ₂ etc. can be formed by sputtering targeting Al ₂ O ₃ , SiO, SiO ₂ etc. By process, for example, polyparaxylylene is formed by vapor phase thermal synthesis of P-xylylene in vacuo. Also, P-type or n-type doped A-Si:H or/and a-Ge:
For example, when H is formed by a glow discharge method,
Hydride such as SiH ₄ , Si ₂ H ₆ , GeH ₄ as it is,
or these gases Ar diluted with Ar, _H2 , etc.
_{B 2 H 6} (P type), PH ₃ , AsH ₃ (n
A mixed gas with a gas such as mold) is introduced into the deposition tank, and is decomposed and deposited by glow discharge. Impurity B doped to a-Si:H or/and a-Ge:H
(P-type), P, As (n-type), etc. are usually 10 ^-4 ~
It is desirable that the content be 10 atomic %, preferably 10 ^-3 to 1 atomic %.

The electrophotographic imaging member shown in FIG. 2 is similar to the electrophotographic imaging member 1 shown in FIG. 1 except that the charge injection blocking layer 7 is provided between the support 6 and the lower photoconductive layer 8. be.

Examples will be described in detail below.

Example 1 Using the apparatus shown in FIG. 3 installed in a clean room, an electrophotographic image forming member 1 was produced by the following operations.

An Al plate (substrate) 11 having a surface cleaned and having a thickness of 1 mm and 10×10 cm was firmly fixed to a fixing member 12 in a glow discharge deposition tank 10. The substrate 11 is heated with an accuracy of ±0.5° C. by a heater 13 within the fixing member 12. The temperature was directly measured on the back surface of the substrate 11 using a thermocouple (chromel-alumel).
Next, after confirming that all valves in the system were closed, the main valve 15 was fully opened to evacuate the interior of the vapor deposition tank 10 to a degree of vacuum of approximately 1×10 ^-6 Torr. Thereafter, the input voltage of the heater 13 was increased, and the input voltage was varied while detecting the Al substrate temperature, and was stabilized until it reached a constant value of 200°C.

Thereafter, the auxiliary valves 19, 20, then the outflow valves 21, 23, and the inflow valves 29, 31 were fully opened, and the insides of the flowmeters 25, 27 with needles were also sufficiently evacuated to a vacuum state.

Next, valves 19, 20, 21, 23, 29, 3
After closing 1, Ar dilute 10vol% _SiH4 (hereinafter
Valve 3 of gas cylinder 43 (written as SiH ₄ /Ar)
9 was opened, the pressure of the output pressure gauge 35 was adjusted to 1 Kg/cm ² , and the inflow valve 31 was gradually opened to allow SiH ₄ /Ar gas to flow into the needle-equipped flow meter 27 . Subsequently, the outflow valve 23 was gradually opened, and then the auxiliary valve 20 was gradually opened, and the flow rate of the SiH ₄ /Ar gas was adjusted to 40 c.c./min using the needle of the flow meter 27. After the pressure in the vapor deposition tank 10 became stable, the main valve 15 was gradually closed, and the opening was narrowed until the reading on the Pirani gauge 16 reached 0.1 Torr. After confirming that the internal pressure has stabilized, turn on the switch of the high frequency power supply 18, apply 13.56MHz high frequency power between the upper electrode 14 and the substrate 11, and create a glow between the upper electrode and the substrate 11. A discharge was generated and the input power was 30W. After maintaining the above conditions for 10 hours, turn off the high frequency power supply 18.
state.

While SiH ₄ /Ar gas is flowing, Ar
Open the valve 37 of the diluted 10 vol% O ₂ (hereinafter referred to as O ₂ /Ar) gas cylinder 41, and check the output pressure gauge 33.
The pressure of the O 2 /Ar gas was adjusted to 1 Kg/cm ² , the inflow valve 29, the outflow valve 21, and the auxiliary valve 19 were gradually opened, and the flow rate of O ₂ /Ar gas was adjusted to 1 c.c./min with the needle of the flow meter 25. . After confirming that the internal pressure has stabilized, adjust the opening of the main valve 15,
After setting the indication on the Pirani gauge 16 to 0.1 Torr, the switch of the high frequency power supply 18 was turned on again to generate a glow discharge and set the input power to 30W. After maintaining this condition for 1 hour, high frequency power supply 1
8 was turned off. Next, turn off the power to the heater 13, and turn off the gas cylinder valve 3.
7 and 39, and fully open the main valve 15.
After reducing the inside of the vapor deposition tank 10 to 1×10 ^-5 Torr or less, close the valves 29, 31, 21, 23, 19, and 20, and wait for the substrate temperature to become 100° C. or less.
The main valve 15 was closed, the inside of the vapor deposition tank 10 was returned to atmospheric pressure by the leak valve 16, and the Al substrate 11 on which the vapor deposited film was formed was taken out. the result,
On top of the Al substrate (support 2), a lower photoconductive layer 3
As, an a-Si:H layer is formed to a thickness of 20μ,
On top of that, an oxygen-containing a is formed as the upper layer 4 of the photoconductive layer.
A photoconductive member 1 for electrophotography in which a -Si:H layer was formed to a thickness of 2 μm was obtained.

The electrophotographic image forming member 1 thus obtained is
It was installed in a charging exposure experimental device, corona charged at 6KV for 0.2 seconds, and a light image was immediately irradiated. The optical image is generated using a tungsten lamp light source at 15lux・sec.
of light was irradiated through a transmission type test chart.

Immediately thereafter, a good toner image was obtained on the surface of the imaging member by cascading a chargeable developer (containing toner and carrier) onto the surface of the imaging member. The toner image on the material is transferred onto transfer paper using +5KV corona charging, which has excellent resolution.
Clear, high-density images with good gradation reproducibility were obtained.

Example 2 Using the apparatus shown in FIG. 3 installed in a clean room, a negatively charged electrophotographic image forming member 5 was produced by the following operations.

A stainless steel plate (substrate) 11 of 1 mm thickness and 10×10 cm whose surface had been cleaned was set in the glow discharge deposition tank 10 in the same manner as in Example 1. Next, after confirming that all valves in the system are closed, the main valve 15 is fully opened to exhaust the vapor deposition tank 10.
The degree of vacuum was set to approximately 1×10 ^-6 Torr. Thereafter, the heater 13 was turned on, and while the temperature of the stainless steel substrate was detected, it was stabilized until it reached a constant value of 250°C.

Then the auxiliary valves 19, 20, then the outflow valves 21, 22, 23, and the inflow valves 29, 3.
Fully open 0,31, flow meter 2 with needle
5, 26, and 27 were also sufficiently evacuated to a vacuum state. Next, valves 19, 20, 21, 22, 23, 29,
30 and 31, open the valve 39 of the SiH ₄ /Ar (10%) gas cylinder 43, adjust the pressure of the output pressure gauge 35 to 1 Kg/cm ² , and close the inflow valve 3.
1. Gradually open the outflow valve 23 and auxiliary valve 20, and use the needle of the flow meter 27 to collect SiH ₄ /Ar.
The gas flow rate was adjusted to 10 c.c./min. After confirming that the internal pressure has stabilized, open the valve 38 of the gas cylinder 42 of PH ₃ (hereinafter referred to as PH ₃ /Ar) with Ar dilution of 1000 ppm, and increase the pressure of the output pressure gauge 34 to 1 Kg/cm ²
, gradually open the inflow valve 30 and outflow valve 22, and use the flow meter needle to adjust the pH _{to 3/3} .
The flow rate of Ar gas was adjusted to 10 c.c./min. Vapor deposition tank 1
After the pressure inside the 0 becomes stable, gradually close the main valve 15 until the indication on the Pirani gauge 16 is
The aperture was narrowed down to 0.1Torr. After confirming that the internal pressure has stabilized, turn on the switch of the high frequency power supply 18, apply 13.56 MHz high frequency power between the upper electrode 14 and the substrate 11, generate a glow discharge, and input 10 W. It was used as electricity. After maintaining the above conditions for 30 minutes, the high frequency power supply 18 was turned off. Then close the valves 38, 30, 22,
Stop the PH ₃ /Ar gas, readjust the SiH ₄ /Ar gas to 40c.c./min with the needle of the flow meter 27, adjust the opening of the main valve 15, and set the indication on the Pirani gauge 16 to 0.1. I set it to Torr. Vapor deposition tank 1
After confirming that the pressure inside 0 has stabilized, turn on the switch of the high frequency power supply 18, apply 13.56MHz high frequency power between the upper electrode 14 and the substrate 11, and generate glow discharge again. , with an input power of 30W. After maintaining this condition for 10 hours, the high frequency power supply 18 was turned off. Subsequently, in the same manner as in Example 1, 1 c.c./O ₂ /Ar (10%) gas was added.
The gas pressure of the mixed gas of SiH ₄ /Ar and O ₂ /Ar was adjusted to 0.1 Torr using the main valve, and 30 W of high-frequency power was applied to generate a glow discharge. After maintaining this condition for one hour, turn on the high frequency power supply 18.
It was set to OFF state. Subsequently, heating heater 13
Turn off the power and close the gas cylinder valve 37,
39, open the valves 22 and 30, and fully open the main valve 15.
After reducing the temperature to below 10 ^-5 Torr, valves 29, 30, 3
1, 21, 22, 23, 19, and 20, wait until the substrate temperature becomes 100°C or less, close the main valve 15, and close the leak valve 1 in the vapor deposition tank 10.
6 to return to atmospheric pressure, and the stainless steel substrate 11 on which the vapor deposited film was formed was taken out. As a result, n-type a-Si doped with phosphorus as a charge injection blocking layer 7 on a stainless steel substrate (support 6):
A H layer is formed to a thickness of approximately 1μ, on which an a-Si:H layer is formed to a thickness of 20μ as a lower photoconductive layer 8, and an oxygen-containing layer 9 is formed thereon as an upper layer 9 of the photoconductive layer. An electrophotographic image forming member 5 for negative charging in which a Da-Si:H layer was formed to a thickness of 2 μm was obtained.

The electrophotographic image forming member 5 for negative charging thus obtained was installed in a charging exposure experimental device and heated at 6KV.
Corona charging was performed for 0.2 seconds, and a light image was immediately irradiated. The optical image is created using a xenon lamp light source.
15lux・sec was irradiated through a transmission type test chart.

Immediately thereafter, a good toner image was obtained on the surface of the member by cascading a charged developer (containing toner and carrier) onto the surface of the member. When the toner image on the member was transferred onto transfer paper using +5KV corona charging, a clear, high-density image with excellent resolution and good gradation reproducibility was obtained.

Example 3 Using the apparatus shown in FIG. 3 installed in a clean room, an electrophotographic image forming section 5 was produced by the following operations.

A stainless steel plate (substrate) 11 of 1 mm thickness and 10 x 10 cm whose surface had been cleaned was set in the glow discharge deposition tank 10 in the same manner as in Example 1. Next, after confirming that all valves in the system were closed, the main valve 15 was fully opened to evacuate the interior of the deposition tank 10 to a degree of vacuum of approximately 1×10 ⁻⁶ Torr. Thereafter, the heating heater 13 was turned on, and the temperature was stabilized until a constant value of 250°C was reached while detecting the stainless steel substrate.

Thereafter, the auxiliary valves 19, 20, then the outflow valves 21, 23, and the inflow valves 29, 31 were fully opened, and the insides of the flowmeters 25, 27 with needles were also sufficiently evacuated to a vacuum state. Next, valves 19, 20,
After closing 21, 23, 29, 31, SiH ₄ /Ar
(10%) Open the valve 39 of the gas cylinder 43, adjust the pressure of the output pressure gauge 35 to 1 kg/cm ² , gradually open the inflow valve 31, outflow valve 23, and auxiliary valve 20, and adjust the needle of the flow meter 27. The flow rate of SiH ₄ /Ar gas was adjusted to 40 c.c./min.

Confirm that the internal pressure stabilizes, then add O ₂ /Ar (10
%), open the valve 37 of the gas cylinder 41, adjust the pressure of the output pressure gauge 33 to 1 kg/ ^cm2 , gradually open the inflow valve 29, outflow valve 21, and auxiliary valve 19, and use the needle of the flow meter 25 to
The O ₂ /Ar gas flow rate was adjusted to 20 c.c./min. After confirming that the internal pressure has stabilized, close the main valve 15.
Adjust the opening of the Pirani gauge 16 to read the indication.
I set it to 0.2 Torr. After the internal pressure has stabilized, turn on the high frequency power supply 18 and turn on the upper electrode 14.
A high frequency power of 13.56MHz was applied between the substrate 11 and the substrate 11 to generate glow discharge, resulting in an input power of 10W.

After maintaining this condition for 30 minutes, turn on the high frequency power supply 18.
It was set to OFF state. Next, close the auxiliary valve 19,
The O ₂ /Ar gas was turned off. SiH ₄ /Ar gas is 40
Adjust the opening of the main valve 15 while keeping the flow at a flow rate of cc/min to read the reading on the Pirani gauge 16.
I set it to 0.1Torr. After confirming that the pressure inside the vapor deposition tank 10 has stabilized, turn on the high frequency power supply 18.
After turning it on, a 13.56 MHz high frequency power source was applied between the upper electrode 14 and the substrate 11 to generate glow discharge again, resulting in an input power of 30 W. After maintaining this condition for 10 hours, the high frequency power supply 18 was turned off. Subsequently, in the same manner as in Example 1,
Flow O ₂ /Ar (10%) gas at 1 c.c./min, SiH ₄ /
The gas pressure of the mixed gas of Ar and O ₂ /Ar was adjusted to 0.1 Torr by opening the main valve 15, and 30 W of high frequency power was applied to cause glow discharge. After maintaining this condition for 1 hour, turn off the high frequency power supply 18.
state. Subsequently, the heater 13 is turned off, the gas cylinder valves 37 and 39 are closed, the main valve 15 is fully opened, and the vapor deposition tank 10 is turned off.
After reducing the inside to 1×10 ^-5 Torr or less, valve 29,
31, 21, 23, 19, and 20, wait for the substrate temperature to drop below 100°C, close the main valve 15, and return the inside of the vapor deposition tank 10 to atmospheric pressure using the leak valve 16 to remove the vapor deposited film. The stainless steel substrate 11 on which was formed was taken out. As a result, a charge injection blocking layer 7 is placed on the stainless steel substrate (support 6).
a-, which contains a large amount of oxygen and is close to SiO ₂
A Si:H layer is formed to a thickness of approximately 1 μm, on which an a-Si:H layer is formed to a thickness of 20 μm as a lower photoconductive layer 8, and an upper photoconductive layer 9 is formed thereon. An electrophotographic image forming member 5 in which an oxygen-containing a-Si:H layer was formed to a thickness of 2 μm was obtained.

The electrophotographic image forming member 5 thus obtained is
It was installed in a charging exposure experimental device, corona charged at 6KV for 0.2 seconds, and a light image was immediately irradiated. The optical image was irradiated with 15 lux·sec through a transmission type test chart using a xenon lamp light source.

Immediately thereafter, a good toner image was obtained on the surface of the member by cascading a charged developer (containing toner and carrier) onto the surface of the member. When the toner image on the member was transferred onto transfer paper using +5KV corona discharge, a clear, high-density image with excellent resolution and good gradation reproducibility was obtained.

In Examples 1 to 3, the films were formed by the glow discharge method, but the films can be similarly formed by the sputtering method.

[Brief explanation of the drawing]

1 and 2 are schematic cross-sectional views showing an example of the structure of the electrophotographic image forming member of the present invention, and FIG. 3 is a schematic cross-sectional view of an apparatus for manufacturing the electrophotographic image forming member of the present invention. FIG. 2 is a schematic explanatory diagram showing an example. 1, 5... Image forming member for electrophotography, 2, 6...
Support, 3, 8... lower layer of photoconductive layer, 4, 9...
Upper layer of photoconductive layer, 7... Charge injection blocking layer, 10...
...Vapor deposition tank, 11...Substrate, 13...Heater, 1
4... Upper electrode, 18... High frequency power supply, 15...
Main valve, 25, 26, 27, 28...Flow meter with needle, 41, 42, 43, 44
...Gas cylinder.

Claims (1)

[Scope of Claims] 1. An electrophotographic image forming member having a support and a photoconductive layer, in which the photoconductive layer includes a lower layer made of amorphous silicon or/and germanium containing hydrogen, and 0.1 to 30atomic%
1. An electrophotographic image forming member comprising an upper layer made of amorphous silicon or/and germanium containing oxygen and having a layer thickness of 0.1 to 10 μm. 2. The electrophotographic image forming member according to claim 1, wherein a charge injection blocking layer is provided between the support and the photoconductive layer.