JPH08297374A - Formation of electrophotographic photoreceptive member - Google Patents

Abstract

PURPOSE: To inexpensively and stably supply an electrophotographic photoreceptive member having excellent durability and excellent potential characteristics and image characteristics by suppressing the generation of spherical projections. CONSTITUTION: A vacuum vessel of which internal pressure can be reduced, has a gaseous raw material introducing means, a substrate having electrical conductivity, a microwave introducing means and an electrode in it. The gaseous raw materials introduced into the vacuum vessel are decomposed by using microwaves. While an AC electric field is impressed in a pulse state between the electrode 2114 and the substrate 2112, at least two layers that is, a photoconductive layer consisting of a non-single crystal material, and a surface layer, are formed on the substrate. The image characteristics and more particularly 'white dots', 'white drop-out' and 'flaws' of the electrophotographic photoreceptive member are effectively prevented by impressing the AC electric field in a pulse state thereon. Simultaneously, the interfacial characteristic is improved and an improvement in ghosts and photosensitivity can be obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron sensitive to electromagnetic waves such as light (light in a broad sense, ultraviolet rays, visible rays, infrared rays, x-rays, γ-rays, etc.). The present invention relates to a method for forming a light receiving member for photography.

[0002]

2. Description of the Related Art In the field of image formation, a photoconductive material for forming a light receiving layer in a light receiving member has high sensitivity,
The SN ratio [photocurrent (Ip)] / [dark current (Id)] is high, the absorption spectrum is adapted to the spectral characteristics of the electromagnetic wave irradiated, the photoresponsiveness is fast, and the desired dark resistance value is obtained. Characteristics such as being harmless to the human body when used are required. Particularly, in the case of an electrophotographic light receiving member incorporated in an electrophotographic apparatus used in an office as an office machine, the pollution-free property at the time of use is an important point.

Amorphous silicon is one of the photoconductive materials that has recently been attracting attention based on this point, and a part thereof has already been put to practical use as a light receiving member for electrophotography.

As a method for forming such a light receiving member for amorphous electrophotography, plasma CV by glow discharge is used.
D method (hereinafter, simply referred to as plasma CVD method) can be used.

For example, JP-A-57-115551 discloses an RF plasma CV which decomposes a raw material gas by using an electromagnetic wave having a frequency of 13.56 MHz to cause glow discharge.
An example of depositing a surface layer by the D method is disclosed. Further, JP-A-60-186849 discloses a method of forming a deposited film by a microwave plasma CVD method using a microwave having a frequency of 2.45 GHz as a decomposition source of a raw material gas. Further, Japanese Laid-Open Patent Publication No. 3-219081 discloses a method of forming a deposited film in which a bias is applied to the microwave plasma CVD method to improve the characteristics of the deposited film.

With such a technique, it has become possible to supply an electrophotographic light-receiving member having good electrical characteristics.

[0007]

However, in recent years,
Electrophotographic devices have higher image quality, higher speed,
At the same time as high added value such as high durability is pursued, ozone-free is also an issue in consideration of office environment. In particular, for the a-Si electrophotographic light-receiving member, there is an urgent need for a contact charging method instead of the conventional ozone charging in order to reduce ozone.

At the same time, the demand for cost reduction is increasing along with the support for such new electrophotographic processes.

On the other hand, in the conventional a-Si electrophotographic light-receiving member, abnormal growth of a film called a spherical protrusion is likely to occur during deposition of the a-Si film. These spherical protrusions cause small white spotted image defects called “white spots” on the copy image, and at the same time, the protrusions are missing during long-term use, resulting in new image defects.
When the debris rubs the surface of the electrophotographic light-receiving member, the surface layer may induce "scratches" that are peeled from the surface of the electrophotographic light-receiving member. In addition, dielectric breakdown may occur around these spherical protrusions, and based on this, a so-called "white spot" phenomenon that causes charging failure on the entire axial surface of the electrophotographic light-receiving member is generated, and contact charging method The adaptability was not good.

Further, in the conventional electrophotographic light-receiving member, when image formation is repeated at high speed, a so-called "ghost" phenomenon may occur in which an afterimage of the previous copy image appears on the next copy image. It was

Further, when the deposition film formation rate (deposition rate) is improved in order to cope with the cost reduction, the above-mentioned image defect problem tends to be aggravated.

From such a background, the establishment of a method for manufacturing a light-receiving member for electrophotography, which has the characteristics of satisfying a high-speed electrophotographic process while suppressing the generation of spherical projections, etc. At present, there is a strong demand for.

[Object of the Invention] The present invention has the above-mentioned a.
It is an object of the present invention to solve various problems in a method of forming a light-receiving member for electrophotography composed of —Si.

That is, the main object of the present invention is a means for suppressing the generation of spherical projections, and being able to stably and inexpensively supply a light-receiving member for electrophotography which is excellent in durability, potential characteristics and image characteristics. Another object of the present invention is to provide a method of forming a light receiving member for electrophotography.

Another object of the present invention is to provide a method for forming a photoreceptive member for electrophotography which prevents "white spots" and has a good adaptability to an ozone-less contact charging method, and which takes into consideration the office environment. is there.

Another object of the present invention is to provide a method for forming a photoreceptive member for electrophotography, which essentially reduces optical memory such as ghost and has excellent photosensitivity.

[0017]

SUMMARY OF THE INVENTION The present invention provides a method for forming an electrophotographic light-receiving member which solves the problems of the electrophotographic light-receiving member as described above.
At least a conductive substrate, a source gas introducing unit, a microwave introducing unit, an electrode, and an electric field (hereinafter referred to as "external electric bias" or simply "bias") between the substrate and the electrode in a vacuum container capable of depressurizing. ) Is applied to decompose the raw material gas introduced by the raw material gas introducing means by glow discharge by the energy of the microwave introduced by the microwave introducing means, and at the same time, Method of forming a photoreceptive member for electrophotography comprising a photoconductive layer composed of at least a non-single crystal material and a surface layer by using a microwave plasma CVD method for forming a deposited film on the substrate while applying an electric field therebetween The electric field is an alternating electric field and is applied in a pulse form.

The inventor of the present invention has made various efforts to analyze the growth of spherical projections of an a-Si electrophotographic light-receiving member and suppress it. As a result, the present invention has been found. The contents will be described below.

In general, the spherical projections are formed by abnormal growth of a film when a foreign substance is mixed into the film, which is used as a nucleus.

It has been found that such spherical protrusions affect the copied image over a range of several times larger than the diameter of the spherical protrusions observed on the surface of the electrophotographic light-receiving member. It was also found that such a tendency is emphasized as the deposition rate of the deposited film is increased in the conventional electrophotographic light-receiving member. Therefore, the present inventor analyzed the relationship between the growth state of the spherical projections, the process of image defect generation, and the deposit rate.

The inventor of the present invention produced electrophotographic light-receiving members under various conditions and observed the cross-section of the spherical projections. As a result, most of these spherical projections grew from the middle of the film of the photoconductive layer. In most cases, a nucleus was actually found at the center of the spherical protrusion. In addition, the growth of the spherical protrusions was found to be different depending on the deposition rate of the deposited film.

Generally, in the case of an electrophotographic light-receiving member formed with a relatively low deposition rate, the boundary between the normal growth portion and the spherical projection portion is not clear. In addition, some
It was also observed that even if foreign matter was mixed in the deposited film, it did not grow as spherical projections to the surface of the electrophotographic light-receiving member, but returned to normal film growth in the middle.

On the other hand, in the case of the electrophotographic light-receiving member deposited with a relatively high deposition rate, the boundary between the normal growth portion and the spherical projection portion is clearly separated. In addition, voids were observed in most of these boundaries.

Such a difference in the structure of the spherical protrusions has a great influence on the electrophotographic characteristics. That is, in most cases, the spherical projections of the electrophotographic light-receiving member formed with a relatively low deposition rate do not appear as "white spots" on the copy image, whereas in the case of a relatively high deposition rate,
The voids facilitate the flow of electric charges, and the potential drops over a wider range than the actual size of the spherical protrusions, resulting in a large “white spot” appearing on the image. Further, when such spherical projections are applied to contact charging (roller charging), dielectric breakdown is likely to occur, and a so-called "white spot" in which electric current is concentrated at one location and charging failure occurs at other locations is extremely likely to occur.

Further, the spherical projection having a void at the boundary with a normal film naturally has poor adhesion and is easily peeled off during long-term use. Such spherical protrusions cause damage to the surface of the electrophotographic light-receiving member.

In particular, in the case of roller charging, in some cases, the surface layer damaged by such peeled spherical projections develops until it peels off.

The difference in the structure of such spherical projections due to the deposition rate of the deposited film seems to be related to the essential formation process of the deposited film. For example, in the case of a deposited film formed with a relatively low deposition rate, when the active species in the plasma combine as a deposited film, sufficient relaxation time and mobility of the active species on the surface are ensured, While it is easy to form a three-dimensional bond structure, as the deposition rate increases, the tendency becomes insufficient and the two-dimensional bond tends to be promoted, which emphasizes the boundary between the normal deposited film and the spherical protrusion. It is thought that it works to let you.

In fact, according to the observation of the present inventor, in the deposited film having a relatively low depo rate, no remarkable structure is observed in the film, whereas spherical projections having voids at the boundary are generated. Under the conditions for forming the deposited film, a columnar structure was sometimes observed in the film.

The present inventor, based on the above findings,
In order to obtain a method of forming a photoreceptive member for electrophotography that can suppress the occurrence of image defects even when a deposited film is formed with a relatively high deposition rate, various studies are conducted focusing on the energy in plasma. Came. As a result, they have found that the constitution of the present invention is extremely effective in improving the performance of the electrophotographic light-receiving member and suppressing image defects, and completed the present invention.

The action of the pulsed bias in the plasma of the present invention is still unclear, but is thought to be roughly as follows. When the plasma state is changed in a pulse shape as in the present invention, the continuous wave (C
A very high electron temperature is obtained compared to the plasma according to W). It is known that the electron temperature is an important factor that influences the generation process of active species in plasma. Especially, under the formation conditions of the electrophotographic light-receiving member, the conventional electrophotographic light-receiving element is used. It is envisioned that it causes a plasma reaction that promotes coupling that is essentially three-dimensional as compared with the method of forming the members.

If such a reaction is promoted in plasma, as described above, the relaxation time and surface mobility when the active species combine as a deposited film are insufficient in the conventional deposited film forming method. However, even under the condition of high depo rate, it is considered that they are complemented as a result and the three-dimensional connection is maintained.

As a result, according to the method for forming a light-receiving member for electrophotography of the present invention, even when the deposition rate is relatively high, the columnar structure as in the conventional case is not recognized, and therefore the spherical projections are not formed. Even if it exists, it does not lead to the image defect, so that it has a great effect on the suppression of the image defect.

In addition, the method of forming a light-receiving member for electrophotography of the present invention also has a great effect on improving the characteristics, particularly when the interface of the deposited film is formed. For example, in the case of forming the interface between the photoconductive layer and the surface layer, when the discharge is cut off at the interface and then the discharge is performed again, there is a problem in the bondability of the deposited film formed immediately after the re-discharge, or There is a problem that the surface of the already formed layer is damaged. In addition, in order to improve the peeling of the surface layer due to the scratches as described above, in the case of taking measures such as providing an intermediate region for continuously changing the film composition etc. between the photoconductive layer and the surface layer, the intermediate region In some cases, a localized level or an absorption layer is easily generated, which may cause a ghost phenomenon or worsen photosensitivity.

According to the method of forming the light-receiving member for electrophotography of the present invention, even in such interface formation, the reaction in the plasma is promoted so that the interface having high adhesion between the photoconductive layer and the surface layer is formed. It is formed. Further, even in the case of forming the intermediate region, compared to the conventional method of forming a light receiving member for electrophotography,
Since the intermediate region is stably formed at a high electron temperature, it is possible to further improve the adhesion at the interface without causing the ghost and the deterioration of the photosensitivity as in the conventional case.

The thickness of the intermediate region in the present invention is such that a substantial interface is formed between the photoconductive layer and the surface layer, and the thickness between the photoconductive layer and the surface layer is gentle. connection,
It does not mean a so-called interfaceless state in which the interface cannot be specified in terms of composition, optical characteristics, and the like.

As described above, in the method for forming the electrophotographic light-receiving member of the present invention, the image characteristics required as the electrophotographic light-receiving member can be improved by using the bias on the pulse.

The effects of the present invention and the method for forming the electrophotographic light-receiving member of the present invention will be specifically described below with reference to the drawings.

The electrophotographic light-receiving member formed according to the present invention comprises at least a photoconductive layer made of a non-single crystal material and a surface layer. FIG. 1 is a view schematically showing an example of the layer structure of a light receiving member for electrophotography formed by the present invention. In FIG. 1, 101 is a substrate,
Reference numeral 102 denotes a photoconductive layer, and 103 denotes a surface layer. In the present invention, in addition to the above layer structure, for example, a lower charge injection blocking layer, an adhesion layer, etc. may be provided between the photoconductive layer 102 and the base 101. Further, a so-called function-separated layer structure in which a charge transport layer, a charge generation layer, and the like are used as the photoconductive layer can be used.

Further, an intermediate region having a continuously changed composition can be provided between the photoconductive layer 102 and the surface layer 103. The thickness of the intermediate region in the present invention is such that a substantial interface is formed between the photoconductive layer and the surface layer, and the photoconductive layer and the surface layer are connected smoothly. It does not mean a so-called interfaceless state in which the interface cannot be specified in terms of composition, optical characteristics, and the like.

The raw material gas used in the present invention is selected according to the production scale and characteristics of the electrophotographic light-receiving member, the layer structure and the like.

For example, when forming the electrophotographic light-receiving member having the layer structure shown in FIG. 1, the photoconductive layer 102 basically depressurizes the inside of the source gas for supplying Si, which can supply silicon atoms (Si). It is formed by introducing it into a possible reaction vessel in a desired gas state and causing a glow discharge in the reaction vessel.

The substances that can be used as the source gas for supplying Si in the present invention include SiH ₄ and Si ₂ H
₆ , Si ₃ H ₈ , Si ₄ H _10, etc. in a gas state or gasifiable silicon hydrides (silanes) are mentioned as being effectively used, and further, they are easy to handle during layer formation, S
iH ₄ and Si ₂ H ₆ are mentioned as preferable in terms of good supply efficiency. In addition, these raw material gases for supplying Si may be diluted with a gas such as H ₂ , He, Ar, or Ne as needed before use.

Further, in the present invention, it is effective to introduce an atom for controlling conductivity into the photoconductive layer 102, and it is also effective to introduce a halogen atom such as a fluorine atom as a modifier. .

In the present invention, in the photoconductive layer 102
It is also effective to introduce atoms to control conductivity.
However, if a halogen atom such as a fluorine atom is introduced as a modifier,
It is also effective to enter. Control the conductivity of the photoconductive layer
Atoms, such as group III or group V atoms,
To introduce structurally, a group III atom conductor must be used during layer formation.
Raw material for import or raw material for introducing Group V atom
Others for forming a photoconductive layer in the reaction vessel in the gas state
It may be introduced together with the gas. Group III atom introduction
Or a raw material for introducing a group V atom.
It can be gaseous or low at room temperature and pressure.
A material that can be easily gasified under the conditions for forming at least layers is used.
It is desirable to be. Sources for introducing such group III atoms
Specifically, as a raw material, for introducing a boron atom, B is used.
₂ H₆ , B_Four H_Ten, B_Five H₉ , B _Five H₁₁, B₆ H_Ten, B
₆ H₁₂, B₆ H₁₄Borohydride, BF, etc.₃ , BCl₃ ,
BBr₃ And the like, such as fluorinated boron. Besides this, Al
Cl₃ , GaCl₃ , Ga (CH₃ )₃ , InCl₃ ,
TlCl₃ Etc. can also be mentioned.

In the present invention, as a raw material for introducing a group V atom, phosphorus hydrides such as PH ₃ , P ₂ H _{4 and the} like, PH ₄ I, PF are effectively used for introducing a phosphorus atom.
₃ , PF ₅ , PCl ₃ , PCl ₅ , PBr ₃ , PBr
₅ , fluorinated phosphorus such as PI ₃ may be mentioned. Besides this, AsH
₃ , AsF ₃ , AsCL ₃ , AsBr ₃ , AsF ₅ , S
bH ₃ , SbF ₃ , SbF ₅ , SbCl ₃ , SbCl
₅ , BiH ₃ , BiCl ₃ , BiBr _{3 and the} like can also be mentioned as effective starting materials for introducing a Group V atom.

Halogen compounds which can be preferably used in the present invention are specifically fluorine gas (F ₂ ), BrF,
ClF, ClF ₃ , BrF ₃ , BrF ₅ , IF ₃ , IF
An interhalogen compound such as ₇ can be mentioned. Specific examples of the silicon compound containing a halogen atom, that is, a silane derivative substituted with a halogen atom include, for example, S
Silicon fluorides such as iF ₄ and Si ₂ F ₆ can be mentioned as preferable ones.

In the present invention, the layer thickness of the photoconductive layer 102 is appropriately determined as desired in view of obtaining desired electrophotographic characteristics and economical effects, and is preferably 5 to 5.
50 μm, more preferably 10 to 40 μm, optimally 1
The thickness is preferably 5 to 30 μm.

The temperature (Ts) of the substrate is appropriately selected in accordance with the layer design, but in the usual case, it is preferably 20 to 500 ° C, more preferably 50 to 480 ° C, most preferably 100 to 450 ° C. Is desirable.

When a surface layer made of, for example, amorphous silicon carbide (a-SiC) is provided as the surface layer 103 of the present invention, the above-mentioned Si supply gas capable of supplying Si is basically used, It is formed by introducing a gas for introducing C capable of supplying carbon atoms (C) into a reaction vessel whose inside can be decompressed in a desired gas state, and causing glow discharge in the reaction vessel.

In the present invention, as a material that can be used as a raw material for introducing carbon atoms, a material that is gaseous at room temperature and normal pressure or that can be easily gasified under at least the above-mentioned surface layer forming conditions is adopted. desirable. Carbon atom (C)
Starting materials that are effectively used as raw material gases for introduction include C and H as constituent atoms, for example, saturated hydrocarbons having 1 to 5 carbon atoms and ethylene hydrocarbons having 2 to 4 carbon atoms. , Acetylene hydrocarbons having 2 to 3 carbon atoms, and the like.

Specifically, as the saturated hydrocarbon,
(CH_Four ), Ethane (C₂ H₆ ), Propane (C₃ H
₈ ), N-butane (n-C_Four H_Ten), Pentane (C_Five H
₁₂), Ethylene-based hydrocarbons include ethylene (C₂ H
_Four ), Propylene (C₃ H₆), Butene-1 (C_Four H
₈ ), Butene-2 (C_Four H₈ ), Isobutylene (C_Four H
₈ ), Penten (C_Five H_Ten), With acetylene hydrocarbons
Then, acetylene (C ₂ H₂ ), Methylacetylene
(C₃ H_Four ), Butin (C_Four H₆ ) And the like. Well
Further, as a source gas containing Si and C as constituent atoms, S
i (CH₃ )_Four , Si (C₂ H_Five )_Four Alky of Alchemy
You can list them.

In the present invention, when a surface layer made of a-SiC is formed, it is also effective to introduce a halogen atom such as a fluorine atom as a modifying substance in addition to the above substances. In the present invention, as the raw material gas for introducing halogen atoms into the surface layer, in addition to the above substances, C
As a substance that can supply halogen and halogen at the same time, CF ₄ , C
Fluorocarbon compounds such as F ₃ , C ₂ F ₆ , C ₃ F ₈ and C ₄ F ₈ can also be used.

In the present invention, the surface layer 103 preferably has a layer thickness of 0.01 to 50 μm, more preferably 0.05 to 20 μm, from the viewpoint of obtaining desired electrophotographic characteristics and economical effects. It is desirable that the thickness is 0.1 to 10 μm.

In the present invention, the conditions for forming the surface layer 103 can be appropriately determined so that desired electrophotographic characteristics can be obtained. For example, the substrate temperature is appropriately selected in an optimum range, but is preferably 20 to 500 ° C, more preferably 50 to 480 ° C, and most preferably 100 to 450 ° C.

Formation of Electrophotographic Photoreceptor Member in the Present Invention
The pressure inside the reaction vessel at that time depends on the characteristics of the photoreceptor member for electrophotography.
Selected according to the film properties and layer structure
Different but usually 1 × 10 5^-Five~ 100
Torr, preferably 5 × 10 ^-Five~ 30 Torr, optimum
For 1 x 10^-FourIt is preferably set to 10 Torr.

The microwave used in the present invention is 2.45 GHz (± 0.
A frequency of 1 GHz) is used as preferred.

The bias frequency used in the present invention is 10 MHz to 550 MHz in the RF band, VH.
F band and microwave band can be used. Frequency 1
Below 0 MHz, the effect of changing the reaction in plasma as a bias does not appear so much. Conversely, the frequency is 550 MH
If z is exceeded, it becomes difficult to maintain the uniformity of plasma discharge, and uneven thickness of the deposited film may occur in the electrophotographic light-receiving member. It is also effective for the present invention to superimpose a DC electric field on these AC electric fields. In the present invention, the range of these frequency bands is MF for convenience.
The band is 300 kHz to less than 3 MHz, the RF band is 3 MHz to less than 30 MHz, and the VHF band is 30
MHz ~ less than 300MHz, 300M as microwave
It was defined as above Hz.

The frequency of the AC electric field may be constant during the formation of the electrophotographic light-receiving member, or may be changed during the formation of each layer or may be changed during the formation of the same layer. However, when changing the frequency,
It is desirable to change within the above frequency range.

Further, in the present invention, as a pulsed electric field,
The AC electric field, or the electric field obtained by superposing the AC electric field and the DC electric field, which is modulated by the pulse wave can be effectively used.
The modulation by the pulse wave mentioned here refers to so-called amplitude modulation in which the amplitude of the AC electric field is modulated by the pulse wave. In this case, the frequency of the pulse wave is preferably in the frequency range of 100 Hz to 1 MHz. The effect of the present invention can be obtained outside the above range, but at a frequency of 100 Hz or less, for example, the effect tends to decrease as the frequency decreases. Similarly, when the frequency exceeds 1 MHz, the characteristics tend to approach those of CW. Since it is considered that the effect of the present invention utilizes the transient characteristic of the change in the plasma state, the transient characteristic is less likely to appear when the preferable frequency range is exceeded, and the C
It is thought that this is to approach a situation similar to W.

In the present invention, the frequency of the pulse wave may be constant during formation of the electrophotographic light-receiving member, or may be changed during formation of each layer or during formation of the same layer. However, when changing the frequency of the pulse wave, it is desirable to change it within the above frequency range.

The power of the microwave and AC electric field in the present invention is determined by the conditions such as the type of gas used, the characteristics of the electrophotographic light-receiving member to be obtained, the production scale, etc. However, the bias of the pulse wave is used. From the viewpoint of further accelerating the plasma reaction due to the above, when the microwave power is set to 1 when the formation speed of the deposited film formed on the substrate is saturated under the condition when no AC electric field is applied. By setting the range of 0.05 to 0.9, the effect of the present invention can be further enhanced.

The power of the microwave and the alternating electric field may be constant during the formation of the electrophotographic light-receiving member, or may be changed during the formation of each layer or during the formation of the same layer.

Substrate 101 used in the present invention
Is, for example, Al, Cr, Mo, Au, In, Nb, T
Examples include metals such as e, V, Ti, Pt, Pb, Fe, and alloys thereof, such as stainless steel. In addition, polyester, polystyrene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride,
It is also possible to use a substrate obtained by subjecting at least the surface of the electrically insulating substrate such as a film or sheet made of a synthetic resin such as polyethylene or polyamide, glass, or ceramic to the side where the light receiving layer is formed, to a conductive treatment. Further, it is desirable that the side opposite to the side on which the light receiving layer is formed is also subjected to conductive treatment.

The substrate 101 may be in the shape of a cylindrical or plate endless belt having a smooth flat surface or an uneven surface, and its thickness is appropriately selected so that a desired electrophotographic light-receiving member can be formed. Although it is determined, when flexibility is required for the electrophotographic light-receiving member, the thickness can be made as thin as possible within a range in which the function as the substrate can be sufficiently exerted. However, it is usually 10 μm or more from the viewpoint of mechanical strength and the like in manufacturing and handling the substrate.

The method of forming the electrophotographic light-receiving member of the present invention will be described in detail below.

FIG. 2 is a schematic view of an example of an apparatus for forming a light receiving member for electrophotography by the microwave plasma CVD method for carrying out the present invention. 3 is a cross-sectional view of the reaction container, and FIG. 4 is a vertical cross-sectional view of the reaction container.

This apparatus is roughly classified into a deposition apparatus 200.
0, a source gas supply device 2200, an exhaust device (not shown) for reducing the pressure in the reaction vessel 2111, and a power source (not shown) for generating microwaves. The rotary shaft 21 is provided in the reaction vessel 2111 in the deposition apparatus 2000.
16. A heater 2113 for heating the substrate is installed, and the substrate 2112 is fixed on the rotating shaft 2116. The rotating shaft 2116 is connected to the motor 2120 via a gear so that it can rotate. Also the reaction vessel 211
A source gas introduction tube / bias electrode 2114 is installed in the chamber 1, and is connected to a bias power source (high frequency amplifier) 2121. Further, windows 2122 for introducing microwaves are provided above and below the reaction vessel 2111 and are connected to a microwave power source through a waveguide 2115.

The source gas supply device 2200 is composed of SiH ₄ ,
Cylinders 2221 to 2226 of raw material gases such as H ₂ , CH ₄ , He, C ₂ H ₂ , and SiF ₄ and valves 2231 to 223
6, 2241 to 2246, 2251 to 2256, pressure regulators 2261 to 2266, and mass flow controllers 2211 to 2216, and each source gas cylinder is connected to a reaction container via a valve 2260.

When an electrophotographic light-receiving member having the layer structure shown in FIG. 1 is produced using the above apparatus, the procedure is roughly as follows.

First, the base 211 that has been degreased and washed in advance
2 is installed on the rotary shaft 2116 in the reaction container 2111, and the inside of the reaction container 2111 is exhausted by an exhaust device (not shown).
Subsequently, the substrate 211 is heated by the heater 2113 for heating the substrate.
Control the temperature of 2 to the desired temperature between 20 ° C and 500 ° C.

A raw material gas for forming a deposited film is supplied to the reaction vessel 211.
In order to make it flow into 1, the gas cylinder valves 2231-2
236, make sure that the leak valve 2117 of the reaction vessel is closed, and check the inflow valves 2241 to 224.
6, outflow valves 2251 to 2256, auxiliary valve 226
Make sure 0 is open, then first open main valve 2
118 is opened and the reaction vessel 2111 and the gas pipe 22 are opened.
Evacuate 16.

Next, the reading of the vacuum gauge 2119 is about 5 × 10.
^{When the} pressure reaches ^-3 Torr, the auxiliary valve 2260 and the outflow valves 2251 to 2256 are closed.

Thereafter, the gases are introduced from the gas cylinders 2221 to 2226 by opening the valves 2231 to 2236,
Each pressure of 2kg by pressure regulators 2261 to 2266
Adjust to / cm ² . Next, inflow valves 2241-22
46 is gradually opened to introduce each gas into the mass flow controllers 2211 to 2216.

After the preparation for film formation is completed as described above, a photoconductive layer and a surface layer are formed on the substrate 2112.

When the base body 2112 has reached a predetermined temperature, the necessary ones of the outflow valves 2251 to 2256 and the auxiliary valve 2260 are gradually opened to open the gas cylinder 22.
A predetermined gas is introduced from 21 to 2226 into the source gas introduction pipe / bias electrode 2114. Next, the mass flow controllers 2211 to 2216 are adjusted so that each raw material gas has a predetermined flow rate. At that time, the reaction vessel 21
The opening of the main valve 2118 is adjusted while observing the vacuum gauge 2119 so that the pressure inside 11 becomes a predetermined pressure of 1 Torr or less. When the internal pressure is stable, the microwave power source (not shown) is set to a desired power, and the waveguide 2115
Microwaves are introduced into the reaction vessel 2111 through to generate a glow discharge. At this time, the bias power supply (high frequency amplifier) 2121 is simultaneously adjusted in parallel to a desired power to supply the source gas introduction pipe 2114 with an external electric bias.

In this way, the reaction vessel 2 is activated by glow discharge.
The raw material gas introduced into 111 is decomposed, and the substrate 211
A predetermined deposited film is formed on the surface 2. At this time, the base 211
A motor 2120 in which 2 is connected to a rotating shaft via a gear
By rotating with, the deposited film is obtained on the base 2112 without unevenness. After the desired film thickness is formed, the supply of the microwave power and the bias power is stopped, the outflow valves 2251 to 2256 are closed to stop the gas from flowing into the reaction vessel 2111, and the formation of the deposited film is completed.

When a multi-layer structure is adopted as the electrophotographic light-receiving member, the desired layer may be formed by the above procedure and then the same procedure may be repeated again. It goes without saying that the internal pressure, substrate temperature, microwave, bias power, etc. are adjusted.

In the present invention, when an intermediate region having a continuously changed composition or the like is provided between the layers, for example, when the intermediate region is provided between the photoconductive layer and the surface layer, the photoconductive layer is formed by the above operation. After forming the layer, there is a method of gradually and continuously changing the flow rate condition of the raw material gas from the condition at the time of forming the photoconductive layer to the condition at the time of forming the surface layer without stopping the supply of high frequency power. Can be taken. At this time, the outputs of the microwave power source (not shown) and the bias power source 2121 and the main valve 2118 are changed so that the desired conditions at the time of forming the changed layer are obtained while changing the flow rate of the source gas.
Etc. are adjusted as necessary. Needless to say, when the flow rate of the raw material gas is changed, sufficient consideration should be given so as not to cause an extreme pressure change due to gas protrusion or the like. As described above, the thickness of this change region may be such that it substantially forms an interface between the photoconductive layer and the surface layer.

Needless to say, all the outflow valves other than the necessary gas are closed when forming each layer, and each gas is supplied to the reaction vessel 2111.
Inside, outflow valves 2251 to 2256 to reaction vessel 211
In order to avoid remaining in the pipe reaching 1, the outflow valves 2251 to 2256 are closed, the auxiliary valve 2260 is opened, and the main valve 2118 is fully opened to temporarily exhaust the system to a high vacuum. Do it. Needless to say, the above-mentioned gas species and valve operation may be changed according to the preparation conditions of each layer.

[0080]

EXAMPLES Specific examples for demonstrating the effects of the present invention will be described below, but the present invention is not limited thereto.

<Example 1> Using the apparatus for experimentally modifying the deposited film forming apparatus shown in FIG. 2 and following the procedure described above, an aluminum cylinder having a diameter of 108 mm was used as a substrate, and the preparation conditions shown in Table 1 were used. Then, a light-receiving member for electrophotography was produced. In this example, the AC electric field was fixed and the frequency of the pulse wave was changed in the range of 50 Hz to 10 MHz. The duty ratio of the pulse wave was 0.1. In this example, no intermediate region was provided between the photoconductive layer and the surface layer, and the AC electric field and the frequency of the pulse wave were constant between the photoconductive layer and the surface layer. Further, in the present invention, the electric power of the pulsed AC electric field (or the AC electric field superposed with the DC electric field) refers to the electric power obtained at the time of CW multiplied by the duty ratio.

The electrophotographic light-receiving member thus produced was set in an electrophotographic apparatus (NP6060 manufactured by Canon Inc. was used as a roller charging type and modified for this test), and an image was formed by an ordinary electrophotographic process. , "White spots", "scratches", "white spots", ghosts, and photosensitivity, after initial image evaluation and 5 million continuous paper feed durability tests (hereinafter referred to as durability tests) Image evaluation was performed. Separately from this, a scratch strength test was conducted on a single electrophotographic light-receiving member to evaluate the adhesion between the photoconductive layer and the surface layer.

The following criteria were used for evaluation of each item. "White spot": The halogen lamp for image exposure is turned off, a black image on the entire surface (solid black image) is taken, and "white spot" on the image is observed and evaluated.

In the evaluation of "white spots" ◎ "white spots" are not recognized. ○ "white spots" are difficult to distinguish. △ There are clear "white spots", but there is no practical problem. Is shown. "White spots" ... A solid black image was taken in the same manner as "white spots", and the state of "white spots" on the image was observed and evaluated. In the evaluation of "white spots" ◎ "White spots" are not observed at all. △ "White spots" are large, and there is no problem in practical use. “Scratch” ... A solid black image was taken in the same manner as “white spot”, and the state of “scratch” on the image was observed and evaluated. In the evaluation of "scratches" ◎ "Scratches" are not recognized. ○ There are "scratches" but it is difficult to distinguish. △ There are obvious "scratches", but there is no problem in practical use.

Ghost ... A Canon Ghost Test Chart (Part No. FY9-9040) has a reflection density of 1.
1. When a black circle with a diameter of 5 mm is pasted on the platen, and a Canon halftone chart is overlaid on it, the reflection of the black circle with a diameter of 5 mm of the ghost chart that is recognized on the halftone copy in the copy image. The difference between the density and the reflection density of the halftone portion was measured and evaluated.

Regarding Ghosts ⊚ indicates “especially good” ○ indicates “good” Δ indicates “no problem in practical use” x indicates “problem in practical use”

Photosensitivity: The photoreceptive member for electrophotography is charged to a constant dark surface potential. Then, the light image is immediately irradiated. The light image was emitted by using a xenon lamp light source and excluding light in a wavelength range of 550 nm or less using a filter. At this time, the surface potential of the light portion of the electrophotographic light-receiving member is measured with a surface potential meter. The exposure amount is adjusted so that the light portion surface potential becomes a predetermined potential, and the exposure amount at this time is taken as the sensitivity.

Regarding the photosensitivity, ⊚ means “particularly good”, ○ means “good”, Δ means “no problem in practical use”, and “means problem in practical use”.

Scratch strength test: A diamond needle having a diameter of 0.1 mm is placed on the surface of the electrophotographic light-receiving member, and a load is applied, and the needle is moved in the axial direction of the electrophotographic light-receiving member at a speed of 100 mm / min. . At this time, the surface of the electrophotographic light-receiving member is observed, and the adhesion between the photoconductive layer and the film of the surface layer is evaluated based on the magnitude of the load when the surface layer starts to peel.

In the scratch strength test, ⊚ represents “especially good”, ◯ represents “good”, Δ represents “no problem in practical use”, and x represents “problem in practical use”.

<Comparative Example 1> The bias frequency is 105 MHz.
An electrophotographic light-receiving member was produced in exactly the same manner as in Example 1 except that the continuous wave (CW) of z was used. The electrophotographic light-receiving member thus produced was evaluated in the same manner as in Example 1.

The results of Example 1 and Comparative Example 1 are shown in Table 2 above.
Shown in As shown in Table 2, in the method for forming a light receiving member for electrophotography of the present invention, the image characteristics and the adhesion between the photoconductive layer and the surface layer are improved as compared with the bias of the conventional CW. I understand. In addition, the frequency of the pulse wave is 10
It can be seen that the effect of the present invention is further improved by setting it to 0 Hz to 1 MHz.

Example 2 Using the apparatus for experimentally modifying the deposited film forming apparatus shown in FIG. 2 and following the procedure described above, an aluminum cylinder having a diameter of 108 mm was used as a substrate, and the preparation conditions shown in Table 3 were used. Then, a light-receiving member for electrophotography was produced. In this example, the same conditions as in Example 1 were used except that an intermediate region having a continuously changed composition was provided between the photoconductive layer and the surface layer.

The electrophotographic light-receiving member thus produced was set in an electrophotographic apparatus (NP6060 manufactured by Canon Inc. was used as a roller charging type and modified for this test), and the initial characteristics were obtained in the same manner as in Example 1. The characteristics after the durability test and the scratch strength test were evaluated.

<Comparative Example 2> The bias frequency is 105 MHz.
An electrophotographic light-receiving member was produced in exactly the same manner as in Example 2 except that the continuous wave of z (CW) was used. The electrophotographic light-receiving member thus produced was evaluated in the same manner as in Example 2.

The results of Example 2 and Comparative Example 2 are shown in Table 4 above.
Shown in As is apparent from Table 4, in the electrophotographic light-receiving member forming method of the present invention, the image characteristics and the adhesion between the photoconductive layer and the surface layer are improved as compared with the conventional CW bias. confirmed. Further, by comparing with Table 2, it can be seen that by providing the intermediate region, the adhesion between the photoconductive layer and the surface layer is further improved without deterioration of photosensitivity as in the conventional case.

Example 3 Using the apparatus for experimentally modifying the deposited film forming apparatus shown in FIG. 2 and following the procedure described above, an aluminum cylinder having a diameter of 108 mm was used as a substrate, and the preparation conditions shown in Table 5 were used. Then, a light-receiving member for electrophotography was produced. In this embodiment, a pulse wave having a frequency of 400 Hz and a duty ratio of 0.2 is fixed, and the frequency of the alternating electric field is 5M.
It was changed in the range of Hz to 700 MHz. Further, in this example, no intermediate region was provided between the photoconductive layer and the surface layer, and the frequency of the alternating electric field and the pulse wave was constant between the photoconductive layer and the surface layer.

The electrophotographic light-receiving member thus prepared was set in an electrophotographic apparatus (NP6060 manufactured by Canon Inc. was used as a roller charging type and modified for this test), and the same initial characteristics as those of Example 1 were obtained. The characteristics after the durability test and the scratch strength test were evaluated.

Comparative Example 3 An electrophotographic light-receiving member was produced in exactly the same manner as in Example 3 except that the bias was continuous wave (CW). The electrophotographic light-receiving member thus produced was evaluated in the same manner as in Example 3.

The above Example 3 is shown in Table 6 and the result of Comparative Example 3 is shown in Table 7. From the results shown in Tables 6 and 7, it can be seen that the image characteristics are improved by the method for forming a light receiving member for electrophotography of the present invention. Especially, the frequency of AC electric field is 10MHz
It can be seen that the effect of the present invention is further improved by setting the frequency to 550 MHz.

Example 4 Using the apparatus for experimentally modifying the deposited film forming apparatus shown in FIG. 2 and following the procedure described above, an aluminum cylinder having a diameter of 108 mm was used as a substrate, and the preparation conditions shown in Table 8 were used. Then, a light-receiving member for electrophotography was produced. In this example, the microwave power was varied from 0.05 to 1.5 with the power (saturation power) at which the formation rate of the deposited film saturates as 1. Under the conditions shown in Table 8, the formation rate of the deposited film was saturated at a microwave power of 1200 W. Further, in this example, no intermediate region having a continuously changed composition was provided between the photoconductive layer and the surface layer.

The electrophotographic light-receiving member thus produced was set in an electrophotographic apparatus (NP6060 manufactured by Canon Inc. was used as a roller charging type and modified for this test), and the same initial characteristics as those of Example 1 were obtained. The characteristics after the durability test and the scratch strength test were evaluated.

Further, in this example, a relative comparison between the deposition film formation rate and the deposition film formation rate at the saturation power was evaluated as the deposition film formation rate ratio.

Comparative Example 4 An electrophotographic light-receiving member was produced in exactly the same manner as in Example 2 except that the bias was continuous wave (CW). The electrophotographic light-receiving member thus produced was evaluated in the same manner as in Example 4.

The results of Example 4 are shown in Table 9 and the results of Comparative Example 4 are shown in Table 10. From the results shown in Table 9, the method for forming a light-receiving member for electrophotography of the present invention improved image characteristics. Further, it has been found that the image characteristics are particularly improved by setting the microwave power in the range of 0.05 to 0.9 with respect to the power when the formation rate of the deposited film is saturated.

On the other hand, in the conventional method for forming a photoreceptive member for electrophotography shown in Table 10, there was a tendency that the deposition film formation rate gradually decreased as the microwave power was reduced. Along with that, "white spots", "white spots", and "scratches" tend to improve, but on the contrary, ghosts and light sensitivity deteriorate,
It was not possible to obtain the one that satisfied all the conditions including the deposition film formation rate.

Example 5 Using the apparatus modified from the deposited film forming apparatus shown in FIG. 2 for an experiment and using the aluminum cylinder having a diameter of 108 mm as a substrate according to the above procedure, the preparation conditions shown in Table 11 were used. Then, a light-receiving member for electrophotography was produced. In this example, the microwave power was varied from 0.05 to 1.5 with the power (saturation power) at which the formation rate of the deposited film saturates as 1. Under the conditions shown in Table 11, the formation rate of the deposited film was saturated with microwave power of 1100W. Further, in this example, an intermediate region whose composition was continuously changed was provided between the photoconductive layer and the surface layer.

The electrophotographic light-receiving member thus prepared was set in an electrophotographic apparatus (NP6060 manufactured by Canon Inc. was used as a roller charging type and modified for this test), and the same initial characteristics as those of Example 1 were obtained. The characteristics after the durability test and the scratch strength test were evaluated.

Further, in the present embodiment, the relative comparison between the deposition film formation rate and the deposition film formation rate at the saturation power was evaluated as the deposition film formation rate ratio.

The results of Example 5 are shown in Table 12. Table 1
From the results of No. 2, improvement in image characteristics was obtained by the method for forming a light receiving member for electrophotography of the present invention. Further, it has been found that the image characteristics are particularly improved by setting the microwave power in the range of 0.05 to 0.9 with respect to the power when the formation rate of the deposited film is saturated.

Example 6 Using the apparatus for experimentally modifying the deposited film forming apparatus shown in FIG. 2 and following the procedure described above, an aluminum cylinder having a diameter of 108 mm was used as a substrate, and the preparation conditions shown in Table 13 were used. Then, a light-receiving member for electrophotography was produced. In this embodiment, as the external electric bias, a DC electric field is superimposed on the RF band having a frequency of 13.56 MHz. Further, in this example, an intermediate region whose composition was continuously changed was provided between the photoconductive layer and the surface layer.

The electrophotographic light-receiving member thus produced was set in an electrophotographic apparatus (NP6060 manufactured by Canon Inc. was used as a roller charging type and modified for this test), and the same initial characteristics as those of Example 1 were obtained. The characteristics after the durability test and the scratch strength test were evaluated.

Example 7 Using the apparatus for experimentally modifying the deposited film forming apparatus shown in FIG. 2, following the procedure described above, an aluminum cylinder having a diameter of 108 mm was used as a substrate, and the preparation conditions shown in Table 14 were used. Then, a light-receiving member for electrophotography was produced. Further, in this example, an intermediate region whose composition was continuously changed was provided between the photoconductive layer and the surface layer.

The electrophotographic light-receiving member thus produced was set in an electrophotographic apparatus (NP6060 manufactured by Canon Inc. was used as a roller charging type and modified for this test), and the same initial characteristics as those of Example 1 were obtained. The characteristics after the durability test and the scratch strength test were evaluated.

<Embodiment 8> Using the apparatus modified from the deposited film forming apparatus shown in FIG. 2 for an experiment, the aluminum cylinder having a diameter of 108 mm was used as a substrate according to the above procedure, and the preparation conditions shown in Table 15 were used. Then, a light-receiving member for electrophotography was produced. Further, in this example, an intermediate region whose composition was continuously changed was provided between the photoconductive layer and the surface layer.

The electrophotographic light-receiving member thus produced was set in an electrophotographic apparatus (NP6060 manufactured by Canon Inc. was used as a roller charging type and modified for this test), and the same initial characteristics as those of Example 1 were obtained. The characteristics after the durability test and the scratch strength test were evaluated.

The results of Examples 6 to 8 are shown in Table 16. As is clear from Table 16, good results were obtained in all cases.

[0118]

[Table 1]

[0119]

[Table 2]

[0120]

[Table 3]

[0121]

[Table 4]

[0122]

[Table 5]

[0123]

[Table 6]

[0124]

[Table 7]

[0125]

[Table 8]

[0126]

[Table 9]

[0127]

[Table 10]

[0128]

[Table 11]

[0129]

[Table 12]

[0130]

[Table 13]

[0131]

[Table 14]

[0132]

[Table 15]

[0133]

[Table 16]

[0134]

As described above, the present invention has excellent image characteristics and durability by applying an external electric bias in a pulse form when the electrophotographic light-receiving member is formed by the plasma CVD method. It is possible to obtain a light receiving member for electrophotography.

That is, according to the present invention, it is possible to stably and inexpensively supply an electrophotographic light-receiving member that suppresses the generation of spherical projections, has excellent durability, and has excellent potential characteristics and image characteristics. Becomes

Further, it is possible to provide a method for forming a light-receiving member for electrophotography, which is suitable for an ozone-less contact charging system and which prevents "white spots" and which is friendly to the office environment.

Further, it is possible to provide a method for forming a photoreceptive member for electrophotography, which is capable of essentially reducing optical memory such as ghost and has excellent photosensitivity.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of a light-receiving member for electrophotography formed by the present invention.

FIG. 2 is a schematic view of an example of a deposited film forming apparatus for carrying out the method for forming a light receiving member for electrophotography of the present invention, and is a longitudinal sectional view of a reaction vessel and an overall configuration diagram of the deposited film forming apparatus.

FIG. 3 is a cross section of the reaction vessel of FIG.

FIG. 4 is a vertical cross section of the reaction vessel of FIG.

[Explanation of symbols]

 100 Electrophotographic Photoreceptive Member 101 Substrate 102 Photoconductive Layer 103 Surface Layer 2000 Deposition Device 2111 Reaction Vessel 2112 Substrate 2113 Substrate Heating Heater 2114 Raw Material Gas Introducing Tube / Bias Electrode 2116 Rotating Shaft 2117 Leak Valve 2118 Main Valve 2119 Vacuum Gauge 2120 Motor 2121 Bias power supply (high frequency amplifier) 2122 Window 2123 Matching box 2124 Signal generator 2200 Gas supply device 2211 to 2216 Mass flow controller 2221 to 2226 Cylinder 2231 to 2236 Valve 2241 to 2246 Valve 2251 to 2256 Valve 2260 Valve

Claims (5)

[Claims] 1. A method of forming a photoreceptive member for electrophotography, comprising a photoconductive layer composed of at least a non-single crystal material and a surface layer on a conductive substrate, wherein a microwave plasma CVD method is used, A photo-receptor for electrophotography, characterized in that a raw material gas is decomposed by glow discharge by wave energy and, at the same time, an alternating electric field is applied in a pulse shape between the substrate and an electrode to form a deposited film on the substrate. Method of forming member. 2. The frequency of the alternating electric field is from 10 MHz to
The method for forming a photoreceptive member for electrophotography according to claim 1, wherein the method is 550 MHz. 3. The AC electric field has a frequency of 100 Hz to 1
3. The method for forming a light receiving member for electrophotography according to claim 1, wherein the light receiving member for electrophotography is modulated by a pulse wave of MHz. 4. The intermediate region in which the composition ratio of the deposited film is continuously changed is provided between the photoconductive layer and the surface layer. A method for forming a light-receiving member for electrophotography. 5. When the power of the microwave is set to 1 when the formation speed of a deposited film formed on a conductive substrate is saturated under the condition that an AC electric field is not applied,
The method for forming a photoreceptive member for electrophotography according to claim 1, wherein the range is from 0.05 to 0.9.