JPS6161101B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for manufacturing an electrophotographic photoreceptor. [Prior Art] Conventionally, photoconductive materials constituting the photoconductive layer of electrophotographic photoreceptors include inorganic photoconductive materials such as Se, CdS, and ZnO, poly-N-vinylcarbazole (PVK), and trinitrofluorenone ( Organic photoconductive materials (OPC) such as TNF) are commonly used. However, in electrophotographic photoreceptors that use these photoconductive materials, there are still various issues that can be resolved, and the conditions may be relaxed to a certain extent, depending on individual circumstances. The reality is that a suitable electrophotographic photoreceptor is used. For example, an electrophotographic photoreceptor using Se as a material for forming a photoconductive layer has a narrow spectral sensitivity range when Se alone is used, so attempts are being made to widen the spectral sensitivity range by adding Te or As. However, although electrophotographic photoreceptors with such Se-based photoconductive layers containing Te and As certainly improve the spectral sensitivity range, optical fatigue increases, so the same original cannot be printed continuously. Repeated copying may cause a decrease in the image density of the copied image and background stains (fogging), and if you continue copying other originals, the image of the previous original may be copied as an afterimage (ghost development). have. 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. Or again,
If the surface of the photoconductive layer is exposed, when a liquid developer is used to visualize (develop) the electrostatic latent image,
Since it comes into contact with the solvent, it is required to have excellent solvent resistance (resistance to liquid development), but it is difficult to say with certainty that the Se-based photoconductive layer always satisfies this requirement. 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, 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, Se-based photoconductive layers are usually formed by vacuum evaporation, which requires a significant capital investment in equipment, and it is difficult to reproducibly form a photoconductive layer with desired photoconductive properties. In order to obtain good results, it is necessary to strictly adjust various manufacturing parameters such as vapor deposition temperature, vapor deposition substrate temperature, degree of vacuum, vapor deposition rate, and cooling rate. Furthermore, since the surface coating layer is formed by pasting a film-like material on the surface of the photoconductive layer via an adhesive or by applying a surface coating layer forming material, the photoconductive layer is formed. Since it is necessary to set up equipment other than the equipment, there is a significant increase in capital investment, which 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 have high dark resistance as a photoconductive layer of an electrophotographic photoreceptor, but crystallization of Se occurs at approximately 65°C.
Because crystallization and development occur at extremely low temperatures, crystallization and development are greatly affected by the ambient temperature during handling after manufacture or during use, and by frictional heat due to rubbing with other parts during the image forming process. 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, in electrophotographic photoreceptors that use ZnO, CdS, etc. as photoconductive layer constituent materials, the photoconductive layer is
It is formed by uniformly dispersing photoconductive material particles such as ZnO or CdS in a suitable resin binder. An electrophotographic photoreceptor having this so-called binder-based photoconductive layer is advantageous in manufacturing compared to an electrophotographic photoreceptor having an Se-based photoconductive layer, and can relatively reduce manufacturing costs. . That is, the binder-based photoconductive layer is prepared by applying a coating solution prepared by kneading ZnO or CdS particles and an appropriate resin binder using an appropriate solvent onto an appropriate substrate, using a doctor blade method,
Since it can be formed by simply applying and solidifying it using a coating method such as a dipping method, it is not necessary to invest as much capital in manufacturing equipment as compared to electrophotographic photoreceptors having Se-based photoconductive layers, and it is also easier to manufacture. The method itself 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 characteristics of the photoconductive layer, there are many parameters that determine the electrical and photoconductive properties as well as the physical and chemical properties of the photoconductive layer. There is a drawback that the conductive layer cannot be formed with good reproducibility, resulting in a decrease in yield and lack of mass productivity. In addition, because the binder-based photoconductive layer is a dispersed system, the entire layer is porous, and as a result, it is highly dependent on humidity, and when used in a humid atmosphere, the electrical properties deteriorate, making it difficult to maintain high quality. In many cases, it becomes impossible to obtain a duplicate 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 developer permeates into the layer together with its carrier solvent due to capillary action, making the above point significant. It is necessary to cover with a surface coating 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 drawback 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 during manufacturing and use to prevent it from coming into contact with the human body or scattering into the surrounding environment. There is a need to. ZnO
When using ZnO binder-based photoconductive layers, 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 slow photoresponsiveness. ing. In addition, in electrophotographic photoreceptors that use organic photoconductive materials such as PVK and TNF, which have been attracting attention recently, organic photoconductive materials such as PVK and TNF are placed on a suitable support such as polyethylene terephthalate whose surface has been conductively treated. This method has the advantage in manufacturing that a photoconductive layer can be formed simply by forming a coating film of a photoconductive material, and the advantage that an electrophotographic photoreceptor with excellent flexibility can be manufactured. moisture resistant,
It lacks corona ion resistance and cleaning properties, and
It has drawbacks such as low photosensitivity and a narrow spectral sensitivity range that is biased toward short wavelengths, so it can only be used in a very limited range. However, some of these organic photoconductive materials contain carcinogenic substances, and there is no guarantee that they are completely harmless to the human body. In this way, electrophotographic photoreceptors using photoconductive materials, which have traditionally been pointed out as materials for forming the photoconductive layer of electrophotographic photoreceptors, have both advantages and disadvantages, so manufacturing and usage conditions are relaxed to some extent. At present, an appropriate electrophotographic photoreceptor suitable for each use is selected and put into practical use. In response to these, amorphous silicon (hereinafter abbreviated as "a-Si") has recently begun to attract interest as a research subject. However, in the early stages of development, the a-Si film exhibits various electrical and optical properties as its structure is influenced by its manufacturing method and equipment conditions, and its reproducibility may vary. had a big problem. For example, in the early stages, a-Si films formed by vacuum evaporation or sputtering methods contained many defects such as voids, which greatly affected their electrical and optical properties. received,
It did not receive much attention as a research material for fundamental physical properties, and no research and development was conducted for its application. However, in early 1976, it was reported that p-n junctions could be realized in a-Si for the first time in amorphous amorphous materials (Applied Physics Letter; Vol 28,
No. 2, 15 January 1976), there has been a great deal of interest since then, and since then, in addition to the ability to obtain p-n junctions by doping impurities, crystalline silicon (abbreviated as c-Si) Since very weak luminescence can be observed with high efficiency in a-Si, research and development efforts have been focused mainly on its application to solar cells. By the way, the a-Si films that have been reported so far were developed for use in solar cells, so their electrical and optical properties are
The reality is that it cannot be used as a photoconductive layer of an electrophotographic photoreceptor. In other words, solar cells convert solar energy into current and extract it, so in order to have a good signal-to-noise ratio and efficiently extract current, a-Si
The resistance of the film must be small, but if the resistance is too low, the photosensitivity will decrease and the signal-to-noise ratio will deteriorate, so one of its characteristics is resistance of 10 ⁵ to 10 ⁸
Approximately Ω・cm is required. However, the resistance (dark resistance) of an a-Si film with this level of resistance (dark resistance) is too low to be used as a photoconductive layer of an electrophotographic photoreceptor, and it is currently not suitable for use as a photoconductive layer of an electrophotographic photoreceptor. , it cannot be used at all by applying known electrophotographic methods. Furthermore, as a photoconductive layer forming material for electrophotographic photoreceptors, bright resistance (resistance when irradiated with light) is required to be about 2 to 4 orders of magnitude smaller than dark resistance.
Since the reported a-Si films have a photoconductive layer of about two digits at most, conventional a-Si films have not been able to provide a photoconductive layer that fully satisfies these characteristics. In addition, previous reports on a-Si films have shown that increasing the dark resistance reduces photosensitivity; for example, in an a-Si film with a dark resistance of 10 ¹⁰ Ωcm, the bright resistance is also the same. Although it has been shown that the value of
In this respect as well, the conventional a-Si film could not serve as a photoconductive layer of an electrophotographic photoreceptor. Furthermore, other requirements other than the above required for the photoconductive layer of an electrophotographic photoreceptor, such as electrostatic properties, corona ion resistance, solvent resistance, light fatigue resistance, moisture resistance, heat resistance,
In terms of abrasion resistance, cleanability, etc., these were completely unknown in the past. [Purpose] The present invention has been made in view of the above-mentioned points, and since it is possible to easily create a closed system for the device at the time of manufacturing, it is possible to avoid adverse effects on the human body, and also to prevent the device from being manufactured once. When used, it is non-polluting and has no effect on the human body, other living things, or the natural environment, has excellent heat resistance and moisture resistance, and has stable electrophotographic properties at all times. The main purpose of the present invention is to provide a method for manufacturing an electrophotographic photoreceptor that is suitable for all environments without being limited by the usage environment, 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 a method for manufacturing an electrophotographic photoreceptor that can easily produce high-quality images with high density, clear halftones, and high resolution. Another object of the present invention is to have high photosensitivity, a wide spectral sensitivity range covering almost the entire visible light range, fast photoresponsiveness, and good abrasion resistance, cleaning properties, and solvent resistance. An object of the present invention is to provide a method for manufacturing an electrophotographic photoreceptor that is excellent in terms of quality. [Structure of the Invention] The present invention has been made as a result of intensive research and study on a-Si from the viewpoint of applying it to the photoconductive layer of an electrophotographic photoreceptor. The a-Si prepared by the method can not only be used satisfactorily as a material for forming the photoconductive layer of an electrophotographic photoreceptor, but also has almost the same characteristics as the photoconductive layer forming material of a conventional electrophotographic photoreceptor. This is based on the fact that it has been found to be extremely superior in terms of The initial object of the present invention was to install a vacuum at a degree of vacuum of 10 ^-2 in an inductively coupled glow discharge tank in which a layer-forming support was disposed and a hydrogen-containing silicon compound gas was introduced.
Under ~3torr, frequency 0.2~30MHz, power 0.1~
By generating a discharge under a 50W discharge condition and decomposing the silicon compound, 0.5-100 Å/
This is achieved by forming a photoconductive layer of amorphous silicon containing hydrogen at a layer growth rate of sec. The most typical structural example of an electrophotographic photoreceptor according to the present invention is shown in FIGS. 1 and 2. The electrophotographic photoreceptor 101 shown in FIG. 1 is composed of a support 102 for the electrophotographic photoreceptor, and a photoconductive layer 103 made of amorphous silicon containing hydrogen (hereinafter abbreviated as "a-Si:H"). and photoconductive layer 103
has a free surface 104 that serves as an imaging surface. The support 102 may be electrically conductive or electrically insulating. Examples of the conductive support include stainless steel, Al, Cr, Mo, Au, Ir, Nb,
Examples include metals such as Ta, 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,
The surface is subjected to conductive treatment by vacuum evaporation treatment with a metal such as Pb, Zn, Ni, or Au, or by lamination treatment with the metal. The shape of the support body is cylindrical,
It can be in any shape, such as a belt or a plate, and its shape is determined as desired, but in the case of continuous high-speed copying, it is preferably in the shape of an endless belt or a cylinder. The thickness of the support is determined as appropriate so that the electrophotographic photoreceptor is formed as desired, but if flexibility is required as an electrophotographic photoreceptor, the thickness of the support may be determined appropriately so that the support functions as a support. It is made as thin as possible within the range. However, in such cases, the thickness is usually set to 10μ or more in view of manufacturing and handling of the support, mechanical strength, etc. The a-Si photoconductive layer 103 is made of a hydrogen atom (H) layer so that electrophotographic properties, especially dark resistance and photosensitivity, satisfy the values required for a photoconductive layer of an electrophotographic photoreceptor. Controlled by inclusion during formation. As a method for incorporating H into the a-Si photoconductive layer 103, when forming the photoconductive layer 103, after introducing into the device system in the form of a compound such as SiH ₄ or Si ₂ H ₆ or H ₂ , Under the above layer forming conditions, such compounds or
_H2 is decomposed by glow discharge and incorporated as the layer grows. According to the findings of the present inventors, the H content in the a-Si photoconductive layer 103 determines whether the formed a-Si layer can be applied as a photoconductive layer of an electrophotographic photoreceptor. It has been found that this is one of the major factors that influences the In the present invention, in order for the a-Si layer to be formed to be sufficiently applicable as a photoconductive layer of an electrophotographic photoreceptor, the amount of H contained in the a-Si layer is preferably
10-40 atomic%, more preferably 15-30 atomic%
It is desirable that this is done. The theoretical basis for why the H content in the a-Si layer is limited to the above-mentioned numerical range has not yet been clarified and remains in the realm of speculation. However, from numerous experimental results, it has been found that if the H content is outside the above numerical range, for example, the dark resistance is too low for the photoconductive layer of an electrophotographic photoreceptor, the photosensitivity is extremely low, or in some cases. It was observed that almost no photosensitivity was observed, and the increase in carrier due to light irradiation was small, supporting that the H content within the above numerical range is a necessary condition. In order to contain H in the a-Si layer,
For example, the starting material for forming a-Si is SiH ₄ ,
When using hydrides such as Si ₂ H ₆ , SiH ₄ ,
When a hydride such as Si ₂ H ₆ is decomposed to form an a-Si layer, H is automatically contained in the layer under the above layer formation conditions. In order to carry out the inclusion even more efficiently, when forming the a-Si layer,
It is sufficient to introduce H ₂ gas into the system that performs glow discharge. In order to control the amount of H contained in the a-Si layer, the support temperature (Ts) during layer formation, discharge conditions,
Pressure, layer growth rate (deposition rate), amount of starting material used to contain H introduced into the system, etc. are selected and controlled as desired based on their mutual relationship. Just do it. Furthermore,
One method is to heat the a-Si layer below the crystallization temperature after forming the a-Si layer. As mentioned earlier, the a-Si layer can be made intrinsic by doping with impurities during manufacturing, and its conductivity type can be controlled, so it is possible to form an electrostatic image on the electrophotographic photoreceptor. It has the advantage that the polarity of charging during formation can be arbitrarily selected. This advantage is that a conventional, for example, Se-based photoconductive layer can be p-type or or at best the intrinsic type (i
This method is much more advantageous than the need to strictly control the temperature of the support to form a p-type. In order to make the a-Si layer p-type, suitable impurities to be doped into the a-Si layer include elements of group A of the periodic table, such as B, Al, Ga, In, and Tl. In the case of n-type,
Elements of group A of the periodic table, such as N, P,
Preferred examples include As, Sb, Bi, and the like.
The amount of these impurities contained in the a-Si layer is
Since it is on the order of ppm, there is no need to pay much attention to pollution, but it is preferable to use something that is as non-polluting as possible. From this point of view, considering the electrical and optical properties of the a-Si photoconductive layer to be formed, for example, B, As, P, Sb
etc. is optimal. The amount of impurity doped into the a-Si layer is
It is determined as appropriate depending on the desired electrical and optical properties, but in the case of impurities in group A of the periodic table, it is usually 10 ^-6 to 10 ^-3 atomic%, preferably 10 ^-5 to 10 -3 atomic%.
10 ^-4 atomic%, in the case of impurities of group A of the periodic table, usually 10 ^-8 to 10 ^-5 atomic%, preferably 10 ^-8 to
It is desirable to set it to 10 ^-7 atomic%. As for the method of doping these impurities into the a-Si layer, an appropriate method is adopted as desired when forming the a-Si layer, and specifically, in the following explanation or examples, Detailed. A-
In an electrophotographic photoreceptor in which the Si-based conductive layer 103 has a free surface 104 and the free surface 104 is subjected to charging treatment for electrostatic image formation, the a-Si-based photoconductive layer 103 and It is more preferable to provide a barrier layer between the support 102 and the support 102, which functions to prevent carrier injection from the support 102 during charging processing during electrostatic image formation. As a material for forming a barrier layer having such a function, an appropriate material is selected and used depending on the type of support selected and the electrical characteristics of the a-Si photoconductive layer to be formed. Ru. Such barrier layer forming materials include, for example, Au, Ir, Pt, Rh, Pd, Mo, etc., and as the support, for example, when the barrier layer forming material is Au, Al etc. are suitable. It is mentioned as a thing. The layer thickness of the a-Si photoconductive layer is determined as appropriate depending on the desired electrophotographic properties and usage conditions, such as whether flexibility is required, but case 5~80μ, preferably 110~70
μ, preferably 10 to 50 μ. In an electrophotographic photoreceptor having a layer structure in which the surface of the a-Si photoconductive layer is exposed as shown in FIG.
Since the refractive index n of the a-Si film is relatively large at approximately 3.35, light is more likely to be reflected on the surface of the photoconductive layer during exposure compared to conventional photoconductive layers, and therefore light is absorbed by the photoconductive layer. The proportion of the amount of light that is lost decreases, and the light loss rate increases. In order to reduce this optical loss rate as much as possible, it is preferable to provide an antireflection layer on the a-Si photoconductive layer. Materials for forming the antireflection layer must not have any adverse effect on the a-Si photoconductive layer and have excellent antireflection properties, but must also have electrophotographic properties, such as resistance above a certain level. thing,
When employing a liquid development method, the a-Si photoconductive layer 103 that has already been formed must have excellent solvent resistance and meet the conditions for forming an antireflection layer.
Conditions such as not degrading the characteristics of the material are required. Furthermore, in order to make antireflection effective, it is clear from simple optical calculation that the material for forming the antireflection layer should have a refractive index between that of the a-Si layer and that of air. It is best to choose as you see fit. Also, the layer thickness should be λ/4√ or (2R+1) times that value (where R is 0.1.2.3...), but considering the light absorption of the antireflection layer itself, it is better to set it to λ/4√. is optimal. (However, n is the refractive index of the a-Si layer, and λ is the wavelength of the exposure light.) Taking these optical conditions into consideration, the thickness of the antireflection layer is determined so that the wavelength of the exposure light is approximately visible. Since it is also in the wavelength range of light, it is preferably 50 to 100 mμ. For example, MgF ₂ , Al ₂ O ₃ , ZrO ₂ ,
TiO ₂ , ZnS, CeO ₂ , CeF ₂ , SiO ₂ , SiO,
Inorganic fluorides and inorganic oxides such as Ta ₂ O ₅ , AlF ₃ , 3NaF, or polyvinyl chloride, polyamide resin, polyimide resin, vinylidene fluoride, melamine resin,
Examples include organic compounds such as epoxy resins, phenolic resins, and cellulose acetate. The electrophotographic photoreceptor 101 shown in FIG.
Although the -Si-based photoconductive layer 103 has a free surface 104, on the surface of the a-Si-based photoconductive layer 103, there are
A surface coating layer such as a protective layer or an electrically insulating layer may also be provided. An electrophotographic photoreceptor having such a surface coating layer is shown in FIG. The electrophotographic photoreceptor 201 shown in FIG.
- Except for having the surface coating layer 204 on the Si-based photoconductive layer 203, the structure is not essentially different from the electrophotographic photoreceptor 101 shown in FIG. The characteristics required for each differ depending on the electrophotographic process to be applied. That is, for example, Japanese Patent Publication No. 42-23910,
If an electrophotographic process such as that described in Publication No. 43-24748 is applied, the surface coating layer 20
4 is required to be electrically insulating, to have sufficient ability to retain static charge when subjected to charging treatment, and to be thicker than a certain level. If applied, it is desirable that the potential of the bright area after electrostatic image formation is very small, so the thickness of the surface coating layer 204 is required to be very thin. In addition to satisfying the desired electrical properties, the surface coating layer 204 should not have any adverse chemical or physical effects on the a-Si photoconductive layer, and should not have any harmful effects on the a-Si photoconductive layer. It is formed taking into consideration electrical contact and adhesive properties, as well as moisture resistance, abrasion resistance, and cleaning properties. Typical materials effectively used as surface coating layer forming materials include polyethylene terephthalate, polycarbonate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polystyrene, polyamide,
polytetrafluoroethylene, polytrifluorochloroethylene,
Synthetic resins such as polyvinyl fluoride, polyvinylidene fluoride, propylene hexafluoride-tetrafluoroethylene copolymer, ethylene trifluoride-vinylidene fluoride copolymer, polybutene, polyvinyl butyral, polyurethane, cellulose derivatives such as diacetate, triacetate, etc. etc. These synthetic resins or cellulose derivatives are made into a film and a
-Si-based photoconductive layer 203 may be laminated onto the a-Si-based photoconductive layer, or a coating solution thereof may be formed to form a-Si-based photoconductive layer 203.
It may be coated on top to form a film. The layer thickness of the surface coating layer is appropriately determined depending on the desired characteristics and the material used, but is usually 0.5
It is estimated to be about ~70μ. In particular, when the surface coating layer is required to function as the above-mentioned protective layer, it is usually 10μ or less, and conversely, when it is required to function as an electrical insulating layer, it is usually It is considered to be 10μ or more. However, the layer thickness value that distinguishes between the protective layer and the electrically insulating layer varies depending on the materials used, the applied electrophotographic process, and the structure of the electrophotographic photoreceptor, and the above value of 10μ is an absolute value. It's not a typical thing. Furthermore, if this surface coating layer 204 is also given the role of an antireflection layer as described above, its function will be greatly expanded and it will become more effective. FIG. 3 is a schematic explanatory diagram of an inductive type (inductively coupled type) glow discharge vacuum deposition apparatus for embodying the method of manufacturing an electrophotographic photoreceptor of the present invention. 301 is a glow discharge vacuum deposition tank, inside of which a substrate (support) 302 for forming an a-Si photoconductive layer is fixed to a fixing member 303;
A heater 304 for heating the substrate 302 is installed on the lower side of the substrate 302. At the top of the vacuum deposition tank, an inductive type (inductively coupled) electrode 30 is connected to a high frequency power source 305.
6,307 is wound, and the high frequency power source 30
5 is turned on, a high frequency is applied to the electrodes 306 and 307, and a glow discharge is generated in the vacuum deposition tank 301. A gas introduction pipe is connected to the upper end of the deposition tank 301, and gas cylinders 308, 309, 310
When the gas in each cylinder is needed, it is transferred to the deposition tank 30.
It is expected to be introduced within 1. 311,31
2 and 313 are flow meters for detecting the flow rate of gas, and 31
4,315,316 are flow control valves, 317,
318 and 319 are valves, and 320 is an auxiliary valve. In addition, the lower end of the deposition tank 301 is connected to a main valve 32.
1 to an exhaust system (not shown). 322 is a valve for breaking the vacuum inside the deposition tank 301. 323 is a mixing tank, and the gas to be used is transferred to cylinders 308,
This tank is used to mix gases in a predetermined proportion in advance and introduce this mixed gas into the deposition tank 301, rather than directly introducing the gases from 309 and 310 into the deposition tank 301. In this way, the method of introducing the gas to be used into the mixing tank 323 at one end, mixing it at a predetermined ratio, and then introducing this mixed gas from the mixing tank 323 into the deposition tank 301 is a method that uses a mixed gas with a constant mixing ratio. This is an extremely effective method because it is introduced into the deposition tank 301 whenever necessary. Using the glow discharge device of FIG.
In order to form an a-Si photoconductive layer with desired characteristics on the substrate 302, first, the substrate 302 is subjected to a predetermined cleaning treatment.
is fixed to the fixing member 303 with the cleaned side facing upward. The method for cleaning the surface of the substrate 302 typically includes
A conventional method, for example, a chemical treatment method using an alkali or an acid, is employed. Alternatively, after being cleaned to some extent, it may be placed at a predetermined position in the deposition tank 301, and glow discharge treatment may be performed before forming an a-Si photoconductive layer thereon. In this case, the board 3
Since the cleaning process of 02 to the formation of the a-Si photoconductive layer can be carried out in the same system without breaking the vacuum, it is possible to avoid dirt and impurities from adhering to the cleaned substrate surface. After fixing the substrate 302 to the fixing member 303, the main valve 321 and the auxiliary valve 320 are fully opened to exhaust the air in the deposition tank 301 and the mixing tank 323 to a degree of vacuum of about 10 ^-5 torr.
After the deposition tank 301 and the mixing tank 323 reach a predetermined degree of vacuum, the heater 304 is ignited to heat the substrate 302, and once the substrate 302 reaches a predetermined temperature, it is maintained at that temperature. Next, close the auxiliary valve 320 and open the gas cylinder 3.
08 valve 317 and gas cylinder 309 valve 318 are fully opened. Gas cylinder 308 is Ar
For diluting gas such as gas, gas cylinder 309
is for raw material gas for forming a-Si,
For example, SiH ₄ , Si ₂ H ₆ , Si ₄ H ₁₀ or a mixture thereof is stored. The cylinder 310 is used for raw material gases for impurities to be introduced into the a-Si photoconductive layer as needed, and stores PH ₃ , P ₂ H ₄ , B ₂ H ₆ and the like. After that, the flow rate adjustment valves 314 and 315 of the gas cylinders 308 and 309 are connected to the flow meter 311.
and 312, the mixing tank 323 is gradually opened, and the mixing tank 323 is filled with the required amount of predetermined gas from the cylinders 308 and 309 at the desired ratio, and a mixed gas, for example, a mixed gas of Ar and SiH ₄ is filled. create. After that, the flow rate adjustment valves 314, 315
is closed, and then the auxiliary valve 320 is gradually opened to introduce the mixed gas from the mixing tank 323 into the deposition tank 301. In this case, dilution gas such as Ar gas is not necessarily required, and SiH ₄
There is no problem even if only the raw material gas for forming the a-Si layer, such as, is introduced. When introducing the dilution gas and the raw material gas for forming an a-Si layer such as SiH ₄ into the mixing tank 323, the quantitative ratio is determined as desired. gas
It is considered to be 10Vol% or more. Also, as a diluent gas, Ar
In addition to gas, He gas may also be used. At this time,
The interior of the deposition tank 301 is maintained at a predetermined degree of vacuum by adjusting the main valve 321, usually at a gas pressure of 10 ^-2 to 3 torr when forming the a-Si layer. Next, when a high frequency voltage of a predetermined frequency, usually 0.2 to 30 MHz, is applied from the high frequency power supply 305 to the inductance type electrodes 306 and 307 wound outside the deposition tank 301, a glow discharge is caused inside the deposition tank 301, for example. , SiH ₄ gas decomposes and the substrate 30
Si is deposited on 2 to form an a-Si layer. When introducing impurities into the a-Si photoconductive layer to be formed, the gas for impurity generation is mixed from the cylinder 310 in the same way as other gases when filling the mixing tank 323 with the gas. tank 3
It would be good to introduce it on the 23rd. In this case, by appropriately adjusting the flow rate control valve 316, the amount of gas introduced into the mixing tank 323 from the cylinder 310 for impurity generation can be appropriately controlled. The amount of impurities introduced into the conductive layer can be controlled arbitrarily. In an inductance type glow discharge device such as the device shown in FIG. 3 according to the present invention, the high frequency power for obtaining a glow discharge that is effective for forming an a-Si layer having desired characteristics may be set as desired. Although it is determined as appropriate, preferably
It is desirable that the power be 0.1 to 50W, most preferably 0.5 to 10W. Even when forming an a-Si photoconductive layer using an inductance typo glow discharge device as shown in FIG.
The properties of the photoconductive layer depend largely on the support temperature during layer growth and the layer growth rate. Therefore, it is necessary to strictly control it. When using an inductance type glow discharge device, the substrate temperature and layer growth rate are preferably in the range of 50 to 350°C, preferably 100 to 200°C. By doing so, an a-Si photoconductive layer having effective characteristics as a photoconductive layer for electrophotography is formed. Further, the substrate temperature can be changed continuously or intermittently during the formation of the a-Si layer to obtain desired characteristics. Further, the layer growth rate is usually 0.5 to 100 Å/sec, preferably 1 to 50 Å/sec. Hereinafter, the present invention will be specifically explained with reference to Examples. Example 1 An electrophotographic photoreceptor was prepared in the following manner using the glow discharge deposition apparatus shown in FIG. 3, and an image was formed by performing an image forming process. 1% of
10cm x 10cm surface treated with NaOH solution, thoroughly washed with water and dried to clean the surface.
An aluminum substrate 302 with a size of 1 mm was prepared and firmly fixed at a predetermined position of a fixing member 303 in a predetermined position in a glow discharge deposition tank 301 at a distance of about 10 cm from a heater 304 . Next, the main valve 321 and the auxiliary valve 32
0 was fully opened to exhaust the air in the deposition tank 301 and the mixing tank 323 to a degree of vacuum of approximately 5×10 ⁻⁵ Torr. Thereafter, the heater 304 was ignited to uniformly heat the aluminum substrate 302 to 150° C., and this temperature was maintained. After that, close the auxiliary valve 320 and open the gas cylinder 3.
The valve 317 of 08 and the valve 318 of the gas cylinder 309 were fully opened. Next, the flow rate adjustment valves 314 and 315 of the gas cylinder 308 for Ar and the gas cylinder 309 for SiH ₄ are connected to the flow meter 31.
1 and 312, the mixing tank 323 is gradually opened and Ar gas and SiH gas are added to the mixing tank 323 in a volume ratio.
It was filled at a ratio of Ar:SiH ₄ =10:1. After that, the flow rate adjustment valves 314 and 315 are closed, and the auxiliary valve 320 is gradually opened to allow the flow into the deposition tank 301.
A mixed gas of Ar and SiH ₄ was introduced. At this time, the main valve 321 was adjusted so that the degree of vacuum in the deposition tank 301 was maintained at about 0.75 torr. Next, turn on the switch of the high frequency power supply 305 and connect the inductance type electrodes 306 and 307.
A glow discharge was generated by applying high frequency power of 13.56 MHz, and an a-Si layer was formed on the aluminum substrate 302. The high frequency power at this time was approximately 5W. Also, the layer growth rate of the a-Si layer at this time is about 3 Å/
sec, and after 20 hours of layer formation,
An a-Si photoconductive layer having a thickness of about 20 μm was formed. Corona discharge was applied to the surface of the a-Si photoconductive layer of the electrophotographic photoreceptor thus prepared in the dark at a power supply voltage of 5500 V, and then image exposure was performed at an exposure dose of 15 lux·sec to form an electrostatic image. When this electrostatic image was developed with toner charged by a cascade method and transferred and fixed onto a transfer paper, an extremely clear image with high resolution was obtained. Example 2 Similar to Example 1, using the apparatus shown in FIG.
An electrophotographic photoreceptor was prepared in the following manner, and an image was formed by performing an image forming process. An a-Si layer was formed on the aluminum substrate 302 with a thickness of 1 mm, which was surface-treated using a 1% NaOH solution, thoroughly washed with water, and dried to clean the surface. The high frequency power at this time was 5W.
In addition, the growth rate of the a-Si layer in this case is approximately 4 Å/
sec and layer formation was carried out for 15 hours to form a 20 μm thick a-Si layer on the aluminum substrate 302.
After completing the layer formation, the electrophotographic photoreceptor produced in this way is attached to the main valve 321 and the auxiliary valve 320.
is closed, and valve 322 is opened instead to close sedimentation tank 30.
The vacuum inside 1 was broken and it was taken out to the outside. On this electrophotographic photoreceptor, corona discharge was applied to the surface of the a-Si photoconductive layer in the dark at a power supply voltage of 5500 V, and then image exposure was performed at an exposure amount of 20 lux sec to form an electrostatic image. When the electrostatic image was developed with toner charged by the cascade method and transferred and fixed onto transfer paper, an extremely clear image was obtained. When we repeated this image forming process and tested the durability of the electrophotographic photoreceptor, we found that the image obtained on the 10,000th sheet of transfer paper was of extremely good quality, and the image on the first sheet of transfer paper was of very good quality. There was no difference at all when compared with the image of the above image, demonstrating that this electrophotographic photoreceptor is extremely durable. Note that blade cleaning was adopted as the cleaning method, and the blade was molded from urethane rubber. Example 3 Similarly to Example 1, using the apparatus shown in FIG.
An electrophotographic photoreceptor was prepared in the following manner, and an image was formed by performing an image forming process. Prepare an aluminum substrate with a thickness of 1 mm and a size of 10 cm x 10 cm, which has been surface-treated with a 1% NaOH solution, thoroughly washed with water, dried, and cleaned, and placed in a designated area in the glow discharge deposition tank 301. A heater 304 is placed at a predetermined position of the fixed member 303 in the position.
It was fixed at a distance of about 10 cm from the Next, the main valve 321 was fully opened to exhaust the air in the deposition tank 301, resulting in a vacuum level of approximately 5×10 ⁻⁵ torr. Thereafter, the heater 304 was ignited, and the aluminum substrate 302 was uniformly heated to 270° C. and maintained at this temperature. After that, the auxiliary valve 320 is fully opened, and then the valve 3 of the cylinder 308 is opened.
17. After fully opening the valve 318 of the cylinder 309, gradually open the flow control valves 314 and 315 to supply Ar gas from the cylinder 308 to the cylinder 30.
9, SiH ₄ gas was introduced into the deposition tank 301.
At this time, adjust the main valve 321 to
The degree of vacuum inside 01 was maintained at approximately 0.75 torr. Also, in this case, the flow meters 311 and 3
12, the flow control valves 314 and 315 were adjusted so that the flow rate of SiH ₄ gas was 10 Vol% of the flow rate of Ar gas. Next, fully open the valve 319 of the cylinder 310,
Thereafter, B ₂ H ₆ gas was introduced into the deposition tank 301 while the flow rate control valve 316 was gradually opened and the flow rate was controlled to be 5×10 ^-3 Vol% of the flow rate of the SiH ₄ gas. At this time as well, the main valve 321 was adjusted to maintain the degree of vacuum in the deposition tank 301 at 0.75 torr. Subsequently, the switch of the high frequency power supply 305 was turned on, and a high frequency voltage of 13.56 MHz was applied to the electrodes 306 and 307 to cause glow discharge, thereby forming an a-Si layer on the aluminum substrate 302. The glow discharge power at this time was 100W. The growth rate of the a-Si layer in this case was about 4 Å/sec, and the layer was formed for 15 hours to form an a-Si photoconductive layer with a thickness of about 20 μm on the aluminum substrate 302. After completing the layer formation, the electrophotographic photoreceptor produced in this manner is assembled into the main valve 321, the auxiliary valve 320, the flow rate adjustment valves 314, 315, 316, and the valve 3.
17, 318, 319 and replace valve 32.
2 was opened to break the vacuum inside the deposition tank 301 and taken out to the outside. On this electrophotographic photoreceptor, corona discharge was applied to the surface of the a-Si photoconductive layer in the dark with a power supply voltage of 5500 V, and then image exposure was performed with an exposure amount of 20 lux·sec to form an electrostatic image. When this electrostatic image was developed with toner charged by the cascade method and transferred and fixed onto transfer paper, an extremely clear image was obtained. When this image forming process was repeated on the electrophotographic photoreceptor and the durability of the electrophotographic photoreceptor was tested, it was found that the image obtained on the 10,000th sheet of transfer paper was of extremely good quality. Even when compared with the image on the first sheet of transfer paper, there was no difference at all, demonstrating that this electrophotographic photoreceptor is extremely durable. Note that blade cleaning was adopted as the cleaning method, and the blade was molded from urethane rubber. Next, with respect to the electrophotographic photoreceptor, in the dark,
Corona discharge was applied with a power supply voltage of 6000V, then 20
Image exposure was performed with an exposure amount of lux·sec to form an electrostatic image. When this electrostatic image was developed using toner charged by the cascade method and then transferred and fixed onto transfer paper, an extremely clear image was obtained. It was found from this result that the electrophotographic photoreceptor obtained in the above-mentioned example had no dependence on charging polarity and had the characteristics of an amphoteric photoreceptor. Example 4 In Example 3, an aluminum substrate was fabricated in the same manner as in Example 3, except that the flow rate of B ₂ H ₆ gas was adjusted to 1 × 10 ^-2 vol% of the flow rate of SiH ₄ gas. An a-Si photoconductive layer having a thickness of about 20 μm was formed on the substrate to prepare an electrophotographic photoreceptor. An image was formed on a transfer paper using this electrophotographic photoreceptor under the same conditions and procedures as in Example 3. The image quality was excellent and extremely clear. From this result, it was found that the electrophotographic photoreceptor obtained in this example had charge polarity dependence. However, the polarity dependence was opposite to that of the electrophotographic photoreceptor obtained in Example 1. Example 5 In Example 1, the electrons indicated by sample No. A photographic photoreceptor was prepared, and an image was formed on a transfer paper under exactly the same image forming conditions as in Example 3, and the results shown in Table 1 below were obtained. As can be seen from the results shown in Table 1, in order to achieve the object of the present invention, it is necessary to form the a-Si layer at a substrate temperature in the range of 50 to 350°C.

[Table] Example 6 In Example 3, samples No. ~ were prepared under exactly the same conditions and procedures as in Example 3, except that the substrate temperature was varied as shown in Table 2 below. The electrophotographic photoreceptor shown was prepared and an image was formed on a transfer paper under exactly the same image forming conditions as in Example 3, and the results shown in Table 2 below were obtained. As can be seen from the results shown in Table 2, in order to achieve the object of the present invention even in the case of this example, the a-Si layer must be formed at a substrate temperature in the range of 50 to 350°C. There is a need.

[Table] Example 7 Sample No. ~ was prepared under the same conditions and procedures as in Example 4, except that the substrate temperature was varied as shown in Table 3 below. The electrophotographic photoreceptor shown was prepared and an image was formed on a transfer paper under exactly the same image forming conditions as in Example 4, and the results shown in Table 3 below were obtained. As can be seen from the results shown in Table 3, in order to achieve the object of the present invention even in the case of this example, the a-Si layer must be formed at a substrate temperature in the range of 50 to 350°C. There is a need.

〔effect〕

As detailed above, according to the present invention, it is possible to easily create a closed system for the device at the time of manufacturing, thereby avoiding adverse effects on the human body, and once manufactured, the device can be used as a closed system. In addition, it is non-polluting, has no impact on the human body, other living things, and the natural environment, and is heat resistant.
It has excellent moisture resistance, stable electrophotographic properties at all times, can be used in all environments, and is extremely resistant to light fatigue and corona ions, and does not cause deterioration even after repeated use. An electrophotographic photoreceptor can be obtained. Further, according to the present invention, it is possible to easily obtain high-quality images with high density, clear halftones, and high resolution, and the photosensitivity is high and the spectral sensitivity range is almost the entire visible light range. It is possible to obtain an electrophotographic photoreceptor that covers a wide range, has fast photoresponsiveness, and has excellent abrasion resistance, cleaning properties, and solvent resistance.

[Brief explanation of the drawing]

1 and 2 are schematic structural sectional views showing an example of the structure of an electrophotographic photoreceptor according to the present invention, and FIG. 3 is a preferred embodiment for embodying the method for manufacturing an electrophotographic photoreceptor according to the present invention. FIG. 2 is a schematic explanatory diagram showing an example of a device. 101,201...electrophotographic photoreceptor, 102,
202...Support, 103,203...Photoconductive layer, 204...Surface coating layer, 104,205...
Free surface, 301... Deposition tank, 305... High frequency power supply, 323... Mixing tank.

Claims (1)

[Claims] 1. Under a vacuum degree of 10 ^-2 to 3 torr in an inductively coupled glow discharge tank in which a support for layer formation is disposed and a silicon compound gas containing hydrogen is introduced, A discharge of 0.5 to 100 Å / A method for producing an electrophotographic photoreceptor, characterized in that a photoconductive layer made of amorphous silicon containing hydrogen is formed at a layer growth rate of sec. 2. The method of manufacturing an electrophotographic photoreceptor according to claim 1, wherein the silicon compound is selected from SiH ₄ , Si ₂ H ₆ , and Si ₄ H ₁₀ . 3. The method of manufacturing an electrophotographic photoreceptor according to claim 1, wherein a gas for introducing impurities is further introduced during the formation of the photoconductive layer. 4 The gas for introducing impurities is PH ₃ , P ₂ H ₄ ,
The method for manufacturing an electrophotographic photoreceptor according to claim 3, wherein the electrophotographic photoreceptor is selected from B ₂ H ₆ . 5. The method for manufacturing an electrophotographic photoreceptor according to claim 1, wherein an inert gas is introduced in addition to the silicon compound gas. 6. The method for manufacturing an electrophotographic photoreceptor according to claim 5, wherein the inert gas is either Ar gas or He gas. 7. The method for manufacturing an electrophotographic photoreceptor according to claim 1, wherein hydrogen gas is further introduced during the formation of the photoconductive layer. 8. The method for manufacturing an electrophotographic photoreceptor according to claim 1, wherein the surface of the support is exposed to electric discharge before the formation of the photoconductive layer.