JPH09311494A - Image forming device and photoreceptor therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoreceptor for an image forming device which is hardly scratched and has durability, and to provide an image forming device which does not show decrease in the image quality even for long-term use. SOLUTION: This photoreceptor 101 is composed of a conductive base body, a photoconductive layer having photoconductive property comprising a nonsingle crystal material essentially comprising silicon atoms and containing hydrogen atoms and/or halogen atoms, and a surface layer having a charge holding function. The surface layer is composed of an amorphous silicon-based film having the following features. The optical band gap near the surface layer of the photoconductive layer is 1.70 to 1.75eV. The characteristic energy at the base of the exponential function obtd. from the absorption spectrum of the subband gap is 50 to 60meV. The local state density is 1×10<14> to 1×10<16> cm<-3> . The surface resistance of the surface layer is 1×10<10> to 1×10<15> Ωcm. The surface layer is formed under conditions of 0.1 to 0.5W/sccm power supply per the unit flow rate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus and a photoconductor for the image forming apparatus.

[0002]

2. Description of the Related Art Image Forming Apparatus The image forming apparatus is widely used not only in a so-called conventional copying machine for copying an original document but also in a printer as an output means of a computer or a word processor, which has been in great demand in recent years. Since such printers have been used not only for conventional office use but also for personal use, economics such as low cost and maintenance free are emphasized. Furthermore, from the perspective of ecology, reduction of paper consumption such as double-sided copying and use of recycled paper, energy saving of power consumption reduction, and countermeasures for impact on neighboring organisms by reducing ozone amount, etc. are required with the same importance as economic efficiency. There is.

The corona charger, which has been the mainstream of the conventional charging system, has a metal wire of about 50 to 100 μm and a thickness of 5 to 10
A high voltage of about kV is applied to ionize the atmosphere to charge the opposing object. In the process, the wire itself also adsorbs dirt, so periodic cleaning and replacement are necessary.
In addition, a large amount of ozone is generated due to the corona discharge. Further, there is a problem with the photoconductor heater regarding energy saving.

Electrophotographic photoreceptors used in recent years have a high surface hardness in order to increase the number of printable sheets and are difficult to scrape. Therefore, ozone products derived from ozone generated from a charger by repeated use are exposed to the light. The ozone product remains attached to the body surface, absorbs moisture in a high-humidity environment, and causes lateral flow of surface charge, which causes deterioration of image quality called image deletion.

In order to prevent such image deletion, heating by a heater as described in Japanese Utility Model Publication No. 1-34205 and a magnet roller as described in Japanese Patent Publication No. 2-38956 are used. A method of removing ozone products by rubbing the surface of a photoconductor with a brush formed of magnetic toner, JP-A-61-100.
A method of removing corona products by rubbing the surface of the photoreceptor with an elastic roller as described in Japanese Patent No. 780 has been used. However, although the method of rubbing the surface of the photosensitive member uses an amorphous silicon photosensitive member having an extremely high hardness, it is difficult to reduce the size and cost of the device. Further, the constant heating by the heater causes an increase in power consumption as described above. The capacity of these heaters is usually around 15 to 80 W, which does not necessarily give the impression of a large amount of electricity, but in most cases they are always energized even at night. 5 to 15% of the power consumption of Further, ozone, which is a source of image deletion, may cause health problems for people and living things around the image forming apparatus. Especially in the case of personal use, the amount of emitted ozone must be reduced as much as possible. Therefore, it is indispensable to attach an ozone removing filter that decomposes the generated ozone to make it harmless, resulting in a high cost. As described above, there is a demand for a method of significantly reducing the amount of ozone generated at the time of electrification, not only from an impact on humans and living things but also from an economical point of view. Under these circumstances, charging members that have no or reduced amount of ozone generated,
A charging device and an image forming apparatus are required.

[0006] 2. Contact charging method In order to solve the above problems, various types of charging devices have been proposed. In the contact charging method described in JP-A-63-208878, a charging member to which a voltage is applied is brought into contact with a member to be charged so that the surface to be charged is charged to a desired potential. This contact charging method is, compared with the widely used corona charging method, firstly, the applied voltage required to obtain a desired potential on the surface of the body to be charged can be lowered, and secondly, The fact that there is no or only a very small amount of ozone generated during the charging process and the need for an ozone removal filter is eliminated, and therefore the configuration of the exhaust system of the device is simplified, and further maintenance-free.
In order to prevent image deletion due to low resistance of the surface due to the ozone product generated by ozone generated in the charging process adhering to the image bearing member (for example, the photosensitive member surface) which is the surface to be charged, it is performed all day. It has advantages such as eliminating the need for dehumidification with a heating heater, which can significantly reduce power consumption such as night-time energization. Therefore, such a contact charging method is used in image forming devices such as copiers and laser beam printers, image forming devices such as electrostatic recording devices, image carriers such as photoconductors and dielectrics, and other charged members. As a means for charging the, it has attracted attention as an alternative to the corona charging method and has been put to practical use.

As the above-mentioned conventional well-known contact charging system,
Typically, a blade or a sheet-shaped fixed charging member is brought into contact with a member to be charged, and a bias is applied to the member to perform charging. FIG. 11 shows an example. Reference numeral 1101 denotes a photoconductor (photosensitive drum) that is a member to be charged.
Say. ) Is a drum-type electrophotographic photosensitive member that is rotationally driven by. Reference numeral 1102 denotes a charging member, which includes an electrode (1102a) and a resistance layer (1102b) formed on the charging surface thereof. The electrodes are usually aluminum, aluminum alloy, brass,
A metal such as copper, iron, or stainless steel, or an insulating material such as resin or ceramic that has been subjected to a conductive treatment (coating with a metal coating or conductive paint) is used. The resistance layer is generally made of a resin such as polypropylene or polyethylene, an elastomer such as silicon rubber or urethane rubber, and a conductive filler such as titanium oxide, carbon powder or metal powder dispersed therein. The resistance value of this resistance layer is 1 when measured with an applied voltage of 250 V to 1 kV using a MHI tester manufactured by HIOKI.
It has a resistance of × 10 ³ to 1 × 10 ¹² Ωcm. 1103 is a voltage application power supply (high voltage power supply) for the charging member. The high voltage power supply charges a voltage (Vac + Vdc) obtained by superimposing a DC voltage Vdc on an AC voltage Vac having a peak-to-peak voltage Vpp that is at least twice the charging start voltage. The outer peripheral surface of the photosensitive drum, which is rotationally driven by being applied to the electrode of the member, is uniformly charged. Further, an electrostatic latent image is formed on the photosensitive drum by scanning the image exposure (laser beam printer light) (1104) whose intensity is modulated according to the image signal. This electrostatic latent image is visualized by a developing device (developing sleeve) (1105) coated with a developer, and then transferred to a transfer material (1106) by a transfer roller (1107). Toner remaining on the photosensitive drum without being transferred to the transfer material is removed from the photosensitive drum by a cleaner (cleaning blade) (1108). The transferred image is fixed by a fixing device (not shown), and the transfer material having the image fixed thereon is discharged to the outside of the machine.

As another contact charging method, a method using magnetic powder for the contact charging member has been proposed. JP-A-59-
As in Japanese Patent No. 133569, a new method of a mechanism for charging by charging a magnetic brush-shaped contact charging member made of a magnetic material and magnetic powder (or particles) with an object to be charged, which is an image carrier, has already been proposed. Has been done. FIG. 12 shows an example thereof. 12
Reference numeral 01 is a photosensitive member (photosensitive drum) that is a member to be charged, and is a drum-type electrophotographic photosensitive member that is rotationally driven in the clockwise direction of arrow A at a predetermined process speed. A charging member 1202 is composed of a multi-pole magnetic body (1202a) and a magnetic brush layer (1202b) formed of magnetic powder on its charging surface. The multi-pole magnetic body is usually made of a magnetic material such as a ferrite magnet or a rubber magnet, and is configured like a cylindrical so-called magnet roller. For the magnetic brush layer, magnetic iron oxide (ferrite) powder, magnetite powder, known magnetic toner material, etc. are generally used. The resistance value of the charging member is appropriately selected according to the environment in which it is used, high charging efficiency, pressure resistance of the surface layer of the photoconductor, and the like. The closest gap between the photosensitive drum, which is the image carrier, and the charging member needs to be stably set to a constant distance in order to stably control the nip of the magnetic brush layer. This distance is 50-2000
The range of μm is preferable, and more preferably 100 to 100.
0 μm. Reference numeral 1203 denotes a voltage application power supply (high voltage power supply) for the charging member, and a DC voltage Vdc is applied to the multi-pole magnetic body and the magnetic brush layer of the charging member by this power supply, so that the outer peripheral surface of the photosensitive drum which is rotationally driven is uniform. Be charged to. Further, an electrostatic latent image is formed on the photosensitive drum by scanning the image exposure (laser beam printer light) (1204) whose intensity is modulated according to the image signal. This electrostatic latent image is visualized by a developing device (developing sleeve) (1205) coated with a developer, and then transferred onto a transfer material (1206) by a transfer roller (1207). The toner remaining on the photosensitive drum without being transferred to the transfer material is removed from the photosensitive drum by a cleaner (cleaning blade) (1208). The transferred image is fixed by a fixing device (not shown), and the transfer material having the image fixed thereon is discharged to the outside of the machine. By this method, the contact property and frictional property between the photosensitive drum (charged member) which is an image bearing member and the charging member are improved, and the mechanical abrasion resistance and the like are remarkably improved against deterioration of durability.

3. Amorphous silicon type photoconductor (a-
Si photoconductor) In electrophotography, as a photoconductive material forming the photosensitive layer of the photoconductor, the SN ratio (photocurrent (Ip) /
It has a high dark current (Id), has an absorption spectrum that matches the spectral characteristics of the electromagnetic waves that it irradiates, has a fast photoresponsiveness and has a desired dark resistance value, and that it is harmless to the human body during use, etc. The characteristics of are required. In particular, in the case of a photoconductor for an image forming apparatus that is incorporated in an image forming apparatus used in an office as an office machine, the above-described non-pollution during use is important. Hydrogenated amorphous silicon (hereinafter referred to as "a-Si: H") is a photoconductive material that exhibits excellent properties in this respect.
For example, Japanese Examined Patent Publication (Kokoku) No. 60-35059 describes application as a photoreceptor for an image forming apparatus. a-Si:
The photoreceptor for an image forming apparatus using H is generally a conductive support heated to 50 to 400 ° C., and a vacuum deposition method, a sputtering method, an ion plating method, or a thermal CVD method is applied on the support. A photoconductive layer made of a-Si is formed by a film forming method such as a photo CVD method or a plasma CVD method. Above all, the plasma CVD method, that is, the source gas is decomposed by direct current or high frequency or microwave glow discharge,
A method of forming an a-Si deposited film on a support has been put into practical use as a suitable method. Also, JP-A-54-83746
In the publication, a photoconductor for an image forming apparatus is proposed in which a photoconductive layer of a-Si (hereinafter referred to as "a-Si: X") containing a halogen atom as a constituent element is formed on a conductive support. ing. In this publication, by containing 1 to 40 atom% of halogen atoms in a-Si, the heat resistance is high and good electrical and optical characteristics can be obtained as a photoconductive layer of a photoreceptor for an image forming apparatus. It is said to be possible. Further, Japanese Patent Laid-Open No. 57-11556 discloses a-S
of a photoconductive member having a photoconductive layer composed of an i-deposited film,
In order to improve electrical / optical / photoconductive properties such as dark resistance, photosensitivity, and photoresponsiveness, operating environment properties such as moisture resistance, and stability over time, silicon atoms were used as the base material. A technique is described in which a surface layer made of a non-photoconductive amorphous material containing silicon atoms and carbon atoms is provided on a photoconductive layer made of an amorphous material. Further, Japanese Patent Application Laid-Open No. 60-67951 describes a technique relating to a photoconductor in which a translucent insulating overcoat layer containing amorphous silicon, carbon, oxygen and fluorine is laminated. No. 168161 discloses a surface layer containing 4 silicon atoms, 4 carbon atoms and 4 carbon atoms.
A technique using an amorphous material having hydrogen atoms of 1 to 70 atomic% as a constituent is described. Further, Japanese Unexamined Patent Publication No.
Japanese Patent No. 158650 contains 10 to 40 atomic% of hydrogen, and has an infrared absorption spectrum of 2100 cm ⁻¹ and 2000 c.
By using a-Si: H having an absorption coefficient ratio of the absorption peak of m ⁻¹ of 0.2 to 1.7 for the photoconductive layer, it is possible to obtain a photoconductor for an image forming apparatus having high sensitivity and high resistance. Has been described. On the other hand, in JP-A-60-95551, a
In order to improve the image quality of the Si photoconductor, an image forming process such as charging, exposure, development and transfer is performed while maintaining the temperature in the vicinity of the photoconductor surface at 30 to 40 ° C. There is disclosed a technique for preventing a decrease in surface resistance due to adsorption and a resulting image deletion.
With these technologies, the electrical / optical / photoconductive characteristics and the usage environment characteristics of the photoreceptor for the image forming apparatus are improved,
Along with that, the image quality has improved.

4. Environmentally friendly heater In order to prevent and remove the high-humidity image flow on the photoconductor,
Means for providing a heat source on the inner surface of the photoconductor is well known, and a sheet-shaped or rod-shaped electrothermal heater is generally arranged on the inner surface of the cylindrical photoconductor. Japanese Utility Model Publication No. 1-34205 discloses a heating means using a heater in order to prevent image deletion, but constant heating by the heater causes an increase in power consumption as described above.

[0011]

However, even in the image forming apparatus using the conventional a-Si photosensitive member,
There is a problem that unavoidable scratches occur due to the inclusion of foreign matter or due to contact with other units or parts such as screws during maintenance work. Further, the image quality is deteriorated after a long period of use due to abrasion due to contact of the separation claw of the copy sheet, the developing device, the cleaner and the like. These increase the service cost and become a serious problem that hinders maintenance-free operation.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a durable photoreceptor for an image forming apparatus which is hard to be scratched and worn, and the image quality is not deteriorated even if the photoreceptor is used for a long period of time. An object is to provide a maintenance-free image forming apparatus.

[0013]

Means for Solving the Problems The present inventors have conducted various studies to achieve the above object, and as a result, completed the present invention.

According to a first aspect of the invention, a voltage is applied to a cylindrical charging member composed of at least a multipolar magnetic material and magnetic powder, and the magnetic powder is brought into contact with an object to be charged, which is an image carrier, and the object to be charged. In an image forming apparatus that charges a charged body to form an electrostatic latent image on the charged body, the charged body is at least a conductive support and a hydrogen atom and / or a halogen atom having a silicon atom as a base. A photoconductor for an image forming apparatus, comprising a photoconductive layer having a photoconductivity made of a non-single-crystal material containing and a surface layer having a charge retaining function, the photoconductive layer being at least in the vicinity of the surface layer. , The optical band gap is 1.70 to 1.75 eV, the characteristic energy of the exponential tail obtained from the subband gap optical absorption spectrum is 50 to 60 meV, and the localized state density is 1 × 10 ¹⁴ to 1
× 10 ¹⁶ cm ⁻³ , the electric resistance of the surface layer is 1 × 10 ¹⁰ to 1 × 10 ¹⁵ Ωcm, and the surface layer has an applied power of 0.1 to 0.5 W / unit flow rate. The present invention relates to an image forming apparatus, which is an amorphous silicon-based surface layer formed in a sccm range.

The second invention relates to the image forming apparatus of the first invention, characterized in that an intermediate layer is provided between the photoconductive layer and the surface layer.

According to a third aspect of the present invention, there is provided a means for cooling the charged body, the surface temperature of the charged body being room temperature or higher and 25 to 30.
The present invention relates to the image forming apparatus of the first or second invention, which is controllable in the range of ° C.

A fourth invention is at least a conductive support.
And a hydrogen atom and / or ha
Photoconductivity consisting of non-single crystal material containing a rogen atom
The photoconductive layer and the surface layer having a charge retaining function.
A photoconductor for an image forming apparatus, comprising the photoconductive layer
Band gap near at least the surface layer of
Is 1.70 to 1.75 eV, sub-bandgap optical absorption
The characteristic energy of the exponential tail obtained from the spectrum is
50-60 meV, density of localized states is 1 × 10¹⁴~ 1 × 1
0¹⁶cm^-3And the electric resistance value of the surface layer is 1 ×
10^Ten~ 1 × 10 ^FifteenΩcm and the surface layer has a unit flow rate
Formed within the range of power input of 0.1 to 0.5 W / sccm
Characterized by an amorphous silicon-based surface layer
And a photoconductor for an image forming apparatus.

A fifth invention relates to a photoreceptor for an image forming apparatus according to the fourth invention, wherein an intermediate layer is provided between the photoconductive layer and the surface layer.

A sixth aspect of the present invention relates to an image forming apparatus provided with the photoconductor for an image forming apparatus of the fourth or fifth aspect.

The inventors of the present invention completed the invention as described above because they paid attention to increasing the hardness of the surface layer of the photoconductor to suppress the generation of scratches.

Therefore, when the relationship between the gas flow rate and the input power was examined in order to increase the altitude of the surface layer, the hardness of the surface layer increased by increasing the input power with respect to the gas flow rate.
It turns out that the scratches are less likely to occur. The sensitivity of the photoconductor decreased as the hardness of the surface layer increased by increasing the applied power, but the hardness of the surface layer could be improved while maintaining the sensitivity under specific conditions.

Further, although the above-described effects have been sufficiently obtained with respect to scratches such as scraping, there is room for further suppression of scratches due to contamination of foreign matter and unavoidable scratches during maintenance work, especially pressure scratches. It was This is because it is considered that the pressure scratches are caused not only in the surface layer but also due to the displacement of the interface between the photoconductive layer and the surface layer. Therefore, by forming a dense and highly adherent film (intermediate layer) between the photoconductive layer and the surface layer, the frequency of occurrence of pressure injuries such as inevitable scratches could be significantly suppressed.

Although the occurrence of scratches could be suppressed as described above, at the same time as forming and using a photoreceptor which is not easily scratched, the scratches should not affect the image even when scratches occur. It is also effective to create an image forming system that does. Therefore, as a result of paying attention to the charging method and the usage temperature of the photoconductor, the above-mentioned photoconductor is used, and the injection charging method (contact charging method) is used as the charging method to further control the usage temperature of the photoconductor. It was found that even when a scratch occurs on the photoconductor, the scratch does not appear in the image. At this time, if the operating temperature is lower than room temperature, image deletion occurs. Therefore, it was effective to set the operating temperature at room temperature or higher and in the range of 25 to 30 ° C. When the conventional image forming apparatus of the corona charging type is used at this temperature, image deletion occurs and scratches appear on the image, resulting in poor image quality. This is due to the temperature rise of the photoconductor, and in the present invention, the effect of the present invention was able to be exhibited by providing a mechanism for cooling the photoconductor to keep the photoconductor at a constant temperature.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to embodiments of the present invention.

Image Forming Apparatus FIG. 1 shows a schematic configuration diagram of an embodiment of the image forming apparatus of the present invention. In the figure, 101 is a photoconductor (photosensitive drum) that is a member to be charged, 102 is a contact type charging member, 104 is image exposure, 105 is a developing device, 107 is a transfer roller, and 108 is a cleaner. With this device, image formation is performed by the processes of charging, latent image formation, exposure, and transfer. Reference numeral 110 denotes a drum heater disposed inside the photoconductor, which is a-Si.
It is configured to heat the photoconductor. Reference numeral 109 denotes a photoconductor cooling device, which adjusts the surface temperature of the photoconductor in cooperation with a drum heater. This cooling device may have a structure for cooling the photoconductor with cold air such as the outside air or an original cooling mechanism, and controls the surface temperature of the photoconductor by contact or contact. It is preferably controllable in the range of 25 to 30 ° C. Furthermore, in order to prevent dew condensation, it is preferable to control the temperature to room temperature or higher.

FIG. 2 shows a schematic configuration diagram of another embodiment of the image forming apparatus of the present invention. A roller type drum heater (210) is provided inside the photoconductor, and a roller contact type cooling device (209) is provided outside the photoconductor. Other configurations are the same as those of the image forming apparatus shown in FIG.

Charging Member The contact-type charging member (102) used in the present invention comprises a multipolar magnetic body (102a) and a magnetic brush layer (102b) made of magnetic powder (FIG. 1). As the multipole magnetic body, a metal such as a ferrite magnet or a magnetic body capable of forming a multipole such as a plastic magnet is usually used. The magnetic flux density depends on many factors such as the process speed used, the electric field due to the potential difference between the applied voltage and the non-charged portion, the dielectric constant and surface property of the charged body, but the distance of 1 mm from the surface of the multipolar magnetic body. The magnetic flux density at the magnetic pole position measured in 1. is preferably 500 gauss (G) or more. More preferably, it is 1000 G or more.

The closest gap between the photoconductor, which is an image carrier, and the multipolar magnetic substance is an appropriate gap such as a roller or a spacer in order to stably control the contact width of the magnetic brush layer (hereinafter referred to as "nip"). Method, it is necessary to stably set a certain distance. This distance is preferably in the range of 50 to 2000 μm,
More preferably, it is 100 to 1000 μm. In addition, a mechanism such as a blade may be provided for adjusting the nip.

The magnetic brush layer made of magnetic powder, which constitutes the above-mentioned charging member, generally uses magnetic powder such as ferrite or magnetite, or a well-known magnetic toner carrier. The particle size of the magnetic powder is generally 1 to 100 μm, but a powder having a larger particle size may be used as long as the image quality is not hindered. Further, in order to improve fluidity, magnetic powders having different particle sizes may be mixed and used.

In the present invention, the charging member having the magnetic brush layer as described above is used in combination with the photosensitive member described later, so that the image is less likely to be scratched and does not appear in the image even if the scratch is generated. A forming system could be made.

Amorphous Silicon-Based Photoreceptor An amorphous silicon-based photoreceptor (hereinafter referred to as “a-Si photoreceptor”), which is one mode of a suitable photoreceptor to be used in the present invention, will be described below. We have a-Si
Focusing on the behavior of carriers in the photoconductive layer of the photoconductor, as a result of diligent study on the relationship between the localized state distribution in the band gap and the temperature dependence of charging ability and the optical memory, at least light is incident on the photoconductive layer. Part of specific energy
It was found that the above object can be achieved by controlling the localized density of states in a certain range. That is, a non-single-crystal forest material containing a hydrogen atom and / or a halogen atom having a silicon atom as a base (hereinafter referred to as “a-Si: H,
X ". In the photoconductor having a photoconductive layer constituted by (1), the photoconductor designed and produced so as to specify the layer structure is not only excellent in practical use but also has a property of By comparison, it was found that they are superior in all respects, and in particular that they have excellent characteristics as a photoreceptor for an image forming apparatus.

The photoreceptor for an image forming apparatus of the present invention comprises at least a conductive support, a photoconductive layer made of a-Si: H, X, and a surface layer described later. The photoconductive layer is made of, for example, a non-single-crystal forest material containing hydrogen atoms having silicon atoms as a base (hereinafter referred to as “a-Si: H”), and in this case, the hydrogen atoms are 10 to 30 atom%. It is preferable to include hydrogen. The photoconductor of the present invention has an optical band gap of 1.70 to 1.75 eV at least in a portion where light is incident (near the surface layer of the photoconductive layer).
The characteristic energy of the exponential tail obtained from the subband gap optical absorption spectrum is 50 to 60 meV, and the localized density of states is 1 × 10 ¹⁴ to 1 × 10 ¹⁶ cm ⁻³ . The photoreceptor for an image forming apparatus of the present invention designed to have the above-mentioned constitution can solve all of the above-mentioned problems, and has extremely excellent electric / optical / conductive characteristics, image quality, and durability. Properties and environmental characteristics of use.

Generally, in the band gap of a-Si: H, a tail level due to structural disorder of Si-Si bond and a dangling bond of Si (dangling bond).
And other deep levels due to structural defects. It is known that these levels act as traps for electrons and holes and as a recombination center, and cause deterioration of device characteristics.

As a method of measuring the state of such a localized level in the band gap, generally, deep level spectroscopy, isothermal capacitance transient spectroscopy, photothermal deflection spectroscopy, constant photocurrent method, etc. are used. . Among them, the constant photocurrent method (Constant Photo
current Method, hereinafter referred to as "CPM". ) Is a-S
It is useful as a method for simply measuring the subgap optical absorption spectrum based on the localized level of i: H.

The present inventors have found that the characteristic energy of the exponential tail (hereinafter referred to as "Eu") and the localized density of states (hereinafter referred to as "DOS") obtained from the optical absorption spectrum measured by the CPM. ") And the characteristics of the photoconductor over various conditions.
The inventors have found that u and DOS are closely related to the temperature characteristics of the a-Si photoconductor and the optical memory, and have completed the present invention.

The reason why the charging ability is lowered when the photosensitive member is heated by a drum heater or the like is that thermally excited carriers (hereinafter referred to as “thermally excited carriers”) are attracted to the electric field at the time of charging, and the base of the band skirts. It can be mentioned that the trapping and emission to the deep local level in the band gap and the band gap travels to the surface while repeating trapping and emission to cancel the surface charge. At this time, the heat-excited carriers that reach the surface while passing through the charger have almost no effect on the decrease in chargeability, but the heat-excited carriers trapped in the deep level are not transferred to the surface after passing through the charger. It is observed as a temperature characteristic in order to reach the surface and cancel the surface charge. In addition, thermally excited carriers that are thermally excited after passing through the charger also cancel the surface charge and cause a reduction in charging ability. Therefore, in order to improve the temperature characteristics, it is necessary to suppress the generation of thermally excited carriers in the operating temperature range of the photoconductor and improve the traveling property of the thermally excited carriers. Further, the optical memory is generated when photo carriers generated by blank exposure or image exposure are trapped in a localized level in the band gap and the photo carriers remain in the photoconductive layer. That is, among the photocarriers generated in a certain copying process, the photocarriers remaining in the photoconductive layer are swept out by the electric field due to the surface charge at the time of the next charging or thereafter, and the potential of the portion irradiated with light is Is lower than that of the image, and as a result, shading occurs on the image. Therefore, it is necessary to improve the traveling property of the photocarrier so that the photocarrier travels in one copying process without remaining in the photoconductive layer. Therefore, by controlling Eu and DOS in a specific energy range as in the present invention, it is possible to suppress the generation of thermally excited carriers and reduce the rate at which thermally excited carriers and photocarriers are trapped in localized levels. Therefore, the traveling property of the carrier (hereinafter referred to as “charge carrier”) is remarkably improved. As a result, the temperature characteristics of the photosensitive member in the operating temperature region are dramatically improved, and at the same time, the generation of optical memory can be suppressed, so that the stability of the photosensitive member in the operating environment is improved and the halftone is reduced. It is possible to stably obtain a high-quality image that clearly appears and has high resolution.

Layer Structure of Photoreceptor Hereinafter, the layer structure of the photoreceptor for an image forming apparatus of the present invention will be described with reference to the drawings. FIG. 3 is a schematic layer configuration diagram of a photoreceptor for an image forming apparatus of the present invention. FIG. 3 (a)
The photosensitive member for an image forming apparatus shown in (1) has a photosensitive layer (302) provided on a support (301). This photosensitive layer is a
-Si: H, X photoconductive layer having photoconductivity (3
03) and an a-Si-based surface layer (304). The photosensitive member for an image forming apparatus shown in FIG. 3B has a photosensitive layer (302) provided on a support (301). The photosensitive layer includes a photoconductive layer (303) made of a-Si: H, X and having photoconductivity, an intermediate layer (305) made of a-Si: H, X, and an a-Si-based surface layer (304). ) And is composed of. In the photoreceptor for an image forming apparatus shown in FIG. 3C, a photosensitive layer (302) is provided on a support (301). This photosensitive layer is composed of a-Si: H, X and has a photoconductive layer (303) having photoconductivity, and a-Si:
It is composed of an intermediate layer (305) composed of H and X, an a-Si based surface layer (304), and an a-Si based charge injection blocking layer (306).

Support of Photoreceptor The material of the support used in the present invention may be conductive or electrically insulating as long as at least the surface on which the photosensitive layer is formed is conductive. Good. As the conductive support, Al, Cr, Mo, Au, In, Nb, T
Metals such as e.V.Ti.Pt.Pd.Fe, and alloys thereof, such as stainless steel, can be used. Also, at least the surface of the electrically insulating member such as polyester or polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polystyrene, polyamide, etc., on which the photosensitive layer is formed, or the surface of the electrically insulating member such as glass or ceramic is formed. A conductively treated support can also be used.

The shape of the support used in the present invention is, for example, a cylindrical or plate-shaped endless belt having a smooth surface or an uneven surface. The thickness is appropriately determined so that a desired photoreceptor for an image forming apparatus can be formed. It can be made as thin as possible within the range that can be sufficiently exhibited. However, the support is 10μ in terms of manufacturing and handling, mechanical strength and the like.
m or more is preferable.

In particular, when image recording is performed using a coherent light such as a laser light, the charge carrier is reduced in order to more effectively eliminate the image defect due to a so-called interference fringe pattern that appears in a visible image. Concavities and convexities may be provided on the surface of the support within a substantially nonexistent range. The irregularities provided on the surface of the support are described in JP-A-60-168156 and JP-A-6-168156.
It can be formed by a known method described in, for example, 0-178457 and 60-225854. Further, as another method of more effectively eliminating the image defect due to the interference fringe pattern in the case of using coherent light such as laser light, a plurality of toner particles on the surface of the support can be used within a range in which charge carrier is not substantially reduced. You may provide the uneven shape by a spherical dent. That is, the surface of the support has irregularities that are smaller than the resolving power required for the photoreceptor for an image forming apparatus, and the irregularities are due to a plurality of spherical dents. Unevenness due to a plurality of spherical trace dents provided on the surface of the support is disclosed in JP-A-61-61
It can be formed by a known method described in Japanese Patent Publication No. 231561. Further, as still another method of more effectively eliminating the image defect due to the interference fringe pattern when coherent light such as laser light is used, interference of a light absorbing layer or the like in the photosensitive layer or on the lower side of the photosensitive layer is performed. A preventive layer or region may be provided.

Photoconductive Layer of Photoreceptor In the photoreceptor for image forming apparatus of the present invention, the photoconductive layer is
In order to effectively achieve the purpose, it is formed on the above-mentioned support and, if necessary, an undercoat layer, and is formed thereon to form the photosensitive layer of the photoreceptor. This photoconductive layer is formed by a vacuum deposition film forming method by appropriately setting numerical conditions of film forming parameters so that desired characteristics can be obtained. Specifically, for example, glow discharge method (low frequency CVD method, high frequency CV
AC discharge CVD method such as D method and microwave CVD method, DC discharge CVD method, etc.), sputtering method, vacuum deposition method,
It can be formed by various thin film deposition methods such as an ion plating method, a photo CVD method, and a thermal CVD method. These thin film deposition methods are appropriately selected and adopted depending on factors such as manufacturing conditions, a load level under capital investment, manufacturing scale, and desired characteristics of a photoreceptor for an image forming apparatus to be manufactured. The glow discharge method, particularly the high-frequency glow discharge method using a power supply frequency in the RF band or the VHF band, is preferable because it is relatively easy to control the conditions in manufacturing the photoconductor for an image forming apparatus having characteristics. .

In order to form a photoconductive layer by the high frequency glow discharge method, basically, a source gas for supplying Si, which can supply silicon atoms (Si), and an H supply, which can supply hydrogen atoms (H). Raw material gas or / and a raw material gas for X supply capable of supplying halogen atom (X) are introduced in a desired gas state into a reaction vessel capable of reducing the pressure inside, and glow discharge is performed in the reaction vessel. A layer made of a-Si: H, X is formed on a predetermined support which is caused to stand in advance.

In the present invention, it is necessary for the photoconductive layer to contain hydrogen atoms and / or halogen atoms, which compensates for dangling bonds of silicon atoms and improves the layer quality, especially the photoconductive property. It is also essential to improve the charge retention characteristics. In the present invention, the content of hydrogen atoms or halogen atoms, or the total amount of hydrogen atoms and halogen atoms is 10 to 10 with respect to the total amount of silicon atoms and hydrogen atoms and / or halogen atoms.
30 atomic% is preferable and 15-25 atomic% is more preferable.

The substances which can be used as the raw material gas for supplying Si in the present invention include SiH ₄ , Si ₂ H ₆ , and
Silicon hydrides (silanes) in a gas state or gasifiable such as Si ₃ H ₈ and Si ₄ H ₁₀ are mentioned as being effectively used. Furthermore, they are easy to handle during layer formation and have good Si supply efficiency. From the above points, SiH ₄ and Si ₂ H ₆ are preferable. Then, structurally introducing hydrogen atoms into the photoconductive layer to be formed, aiming at easier control of the introduction ratio of hydrogen atoms, in order to obtain the film characteristics to achieve the object of the present invention, these It is desirable that a desired amount of a gas of H ₂ and / or He or a silicon compound containing a hydrogen atom is further mixed with the above gas to form a layer. Further, each gas may be mixed not only with a single species but also with a plurality of species at a predetermined mixture ratio.

The effective source gas for supplying halogen atoms used in the present invention is a gaseous or gasified halogen gas, a halide, an interhalogen compound containing halogen, a silane derivative substituted with halogen, or the like. The halogen compounds obtained are preferred. Further, a gaseous or gasifiable silicon hydride compound containing a halogen atom, which contains silicon atoms and a halogen atom as constituent elements, can also be cited as an effective one. Specific examples of the halogen compound that can be preferably used in the present invention include fluorine gas (F ₂ ), BrF, ClF, ClF ₃ , and B.
There may be mentioned interhalogen compounds such as rF ₃ , BrF ₅ , IF ₃ and IF ₇ . As a silicon compound containing a halogen atom, that is, a silane derivative substituted with a halogen atom, specifically, silicon fluoride such as SiF ₄ and Si ₂ F ₆ can be cited as a preferable example.

Hydrogen atoms contained in the photoconductive layer or /
And the amount of halogen atoms can be controlled by, for example, the temperature of the support, the amount of the raw material used to contain hydrogen atoms and / or halogen atoms introduced into the reaction vessel,
Controls discharge power etc.

In the present invention, the photoconductive layer preferably contains atoms for controlling the conductivity, if necessary. Atoms for controlling conductivity are contained in the photoconductive layer in a uniformly distributed state, but may be contained in a nonuniformly distributed state in the layer thickness direction.

As the atom for controlling the conductivity, a semiconductor is used.
The so-called impurities in the body field can be mentioned,
Atoms belonging to group IIIb of the periodic table giving p-type conductivity
(Hereinafter referred to as "Group IIIb atom") or n-type conduction characteristics
Atoms belonging to Group Vb of the periodic table (hereinafter referred to as “Vb
It is called a group atom. ) Can be used. Group IIIb
As atoms, boron (B), aluminum (Al),
Gallium (Ga), Indium (In), Thallium (T
1) and the like, and B, Al, and Ga are particularly preferable. No.
Vb group atoms include phosphorus (P), arsenic (As), anti
Mon (Sb), bismuth (Bi), etc., especially P and A
s is preferred. The content of atoms that control conductivity is
1x10 is better^-2~ 1 × 10^FourAtomic ppm, more preferably
Is 5 × 10 ^-2~ 5 × 10^ThreeAtomic ppm, optimally 1 x 10^-1
~ 1 × 10^ThreeIt is atomic ppm. Atoms that control conductivity, eg
For example, structurally introducing a group IIIb atom or a group Vb atom
In order to form a layer, a raw material for introducing a Group IIIb atom
A substance or a raw material for introducing a Group Vb atom in a gas state
In the reaction vessel, with other gas for forming the photoconductive layer
Introduce to. Raw material for introducing Group IIIb atoms or
As a source material for introducing a group Vb atom
Is gaseous at room temperature and pressure, or at least under layer forming conditions
It is desirable to adopt one that can be easily gasified. this
A raw material for introducing a group IIIb atom is a boron atom.
For introduction, B_TwoH₆, B_FourH_Ten, B_FiveH ₉, B_FiveH₁₁,
B₆H_Ten, B₆H₁₂, B₆H₁₄Borohydride, BF, etc._Three,
BCl_Three, BBr_ThreeSuch as boron halide, etc.
You. In addition, AlCl_Three, GaCl_Three, Ga (CH_Three)_Three,
InCl_Three, TlCl_ThreeAnd the like. Vb
Effectively used as a raw material for introducing a group atom,
For introducing phosphorus atoms, PH _Three, P_TwoH_FourSuch as phosphorus hydride,
PH_FourI, PF_Three, PF_Five, PCl_Three, PCl_Five, PBr_Three,
PBr_Five, PI_ThreeAnd the like. this
Other, AsH_Three, AsF_Three, AsCl_Three, AsBr_Three, AsF
_Five, SbH_Three, SbF_Three, SbF_Five, SbCl_Three, SbC
l_Five, BiH_Three, BiCl_Three, BiBr_ThreeEtc. Group Vb atom
Can be listed as valid starting materials for introduction
You. In addition, raw materials for introducing atoms that control the conductivity of these
H as needed_TwoOr / and diluted with He
May be used.

Further, in the present invention, it is effective that the photoconductive layer contains at least one kind of carbon atom, oxygen atom and nitrogen atom. The content of these atoms is preferably 1 × 10 ⁻⁵ to 10 atom%, more preferably 1 × 10 ⁻⁴ to 8 atom%, with respect to the total amount of silicon atoms, carbon atoms, oxygen atoms and nitrogen atoms. Optimally, it is 1 × 10 ^{−3 to} 5 atom%. These atoms are evenly and uniformly contained in the photoconductive layer, but there may be a portion having a nonuniform distribution in which the content changes in the layer thickness direction of the photoconductive layer.

In the present invention, the layer thickness of the photoconductive layer is appropriately determined as desired in view of obtaining desired electrophotographic characteristics and economic effects, and is preferably 20-5.
0 μm, more preferably 23-45 μm, optimally 25
Is about 40 μm. In order to achieve the object of the present invention and form a photoconductive layer having desired film characteristics, the mixing ratio of the raw material gas for supplying Si and the diluting gas, the gas pressure in the reaction vessel, the discharge power and the support temperature are set. Need to be set appropriately. The flow rate of H ₂ and / or He used as the dilution gas is appropriately selected according to the layer design,
H ₂ or / and He relative to the Si supply gas is usually 3 to 20 times, preferably 4 to 15 times, and most preferably 5 to 1 times.
Control in the range of 0 times. Similarly, the gas pressure in the reaction vessel is appropriately selected in accordance with the layer design, but in the normal case, it is 1 × 10 ^{−4 to} 10 Torr, preferably 5 × 10 ^{−4 to} 5 Torr.
Torr, optimally 1 × 10 ^{−3 to} 1 Torr. Similarly, the discharge power is appropriately selected in accordance with the layer design, but the discharge power with respect to the flow rate of the raw material gas for supplying Si is usually 2 to 7 times, preferably 2.5 to 6 times. Is set to a range of 3 to 5 times. Further, the temperature of the support is appropriately selected according to the layer design,
Preferably from 200 to 350 ° C, more preferably from 230 to
330 ° C, optimally 250-310 ° C. In the present invention, the above-mentioned ranges are mentioned as desirable numerical ranges of the support temperature and gas pressure for forming the photoconductive layer, but these conditions are not usually independently determined separately, In order to form a photoreceptor having the characteristics of
It is desirable to determine the optimum value based on mutual and organic relationships.

Intermediate Layer of Photoreceptor In order to effectively combine the objects in the present invention, an intermediate layer (3) constituting a part of the photosensitive layer on the surface layer side of the photoconductive layer.
05) is preferably provided (FIGS. 3B and 3C). The intermediate layer is formed by appropriately setting the numerical conditions of film forming parameters so that desired characteristics can be obtained by the vacuum deposition film forming method. Basically, the photoconductive layer can be manufactured by the same method as that of the photoconductive layer, and the physical properties of the formed intermediate layer are similar to those of the photoconductive layer. However, since the intermediate layer is on the surface side of the photoconductive layer and is located at the interface with the surface layer, it is necessary to form a film that matches the surface layer in terms of blocking ability and photosensitivity. The intermediate layer used in the present invention has an optical band gab of 1.70 to 1.75 eV and a characteristic energy of an exponential tail obtained from an optical absorption spectrum of 50 to 60 me.
V, and the density of localized states is 1 × 10 ¹⁴ to 1 × 10 ¹⁶ cm ⁻³
It is characterized by being. In order to form such an intermediate layer, it is preferable to reduce the film formation rate to improve the denseness, but the film formation rate is 1 to 10 in consideration of productivity.
A / s is preferable, and 1-5 A / s is more preferable. By using the above intermediate layer, the adhesion between the surface layer and the photoconductive layer is improved, so that the occurrence of pressure scratches can be suppressed.

Surface Layer of Photoreceptor In the present invention, an a-Si based surface layer (304) is formed on the surface of the photoreceptor (FIG. 3). This surface layer has a free surface and is provided to achieve the object of the present invention mainly in moisture resistance, continuous repeated use characteristics, electric pressure resistance, use environment characteristics, and durability. Further, in the present invention, since each of the photoconductive layer forming the photosensitive layer and the amorphous material forming the intermediate layer and the surface layer has a common constituent element of silicon atom, the chemical compound at the stacking interface is used. Sufficient stability is ensured.

Any material can be applied to the surface layer as long as it is an a-Si-based material, and any material having a sufficient charge retention property may be used. For example, hydrogen atom or /
And amorphous silicon containing a halogen atom and further containing a carbon atom (hereinafter referred to as “a-SiC: H, X”), amorphous silicon containing a hydrogen atom and / or a halogen atom and further containing an oxygen atom (hereinafter referred to as “a-SiC: H, X”). a-
SiO: H, X ". ), Amorphous silicon containing a hydrogen atom and / or a halogen atom and further containing a nitrogen atom (hereinafter referred to as “a-SiN: H, X”),
Amorphous silicon containing a hydrogen atom and / or a halogen atom and further containing at least one of a carbon atom, an oxygen atom and a nitrogen atom (hereinafter referred to as “a-SiCON: H, X”).
Say. ) And the like are preferably used. Since the surface layer has a sufficient charge retention function, a material having an electric resistance value of 1 × 10 ¹⁰ to 1 × 10 ¹⁵ Ωcm is used.

In the present invention, in order to effectively achieve the object, the surface layer is formed by a vacuum deposition film forming method by appropriately setting numerical conditions of film forming parameters so that desired characteristics can be obtained. Specifically, for example, the glow discharge method (low frequency CVD method, high frequency CVD method, microwave C
AC discharge CVD method such as VD method, DC discharge CVD method, etc.)
Can be formed by. These thin film deposition methods are based on manufacturing conditions, load level under capital investment, manufacturing scale,
It is appropriately selected and adopted depending on factors such as characteristics desired for the photoreceptor for the image forming apparatus to be formed, but from the viewpoint of productivity of the photoreceptor, it is preferable to use the same deposition method as for the photoconductive layer. For example, by glow discharge method, a-Si
To form a surface layer composed of C: H, X, basically, a source gas for supplying Si, which can supply silicon atoms (Si), and a source gas for supplying C, which can supply carbon atoms (C), can be used. A raw material gas and a raw material gas for supplying H, which can supply hydrogen atoms (H), and / or a raw material gas for supplying X, which can supply halogen atoms (X), are placed in a desired reaction vessel in a reaction vessel. It is introduced in a gas state to cause a glow discharge in the reaction vessel, and a layer made of a-SiC: H, X is formed on a support having at least a photoconductive layer formed in advance at a predetermined position. .

The material of the surface layer used in the present invention may be any a-Si type material containing a silicon atom, but a compound of a silicon atom containing at least one element selected from carbon, nitrogen and oxygen. Are preferable, and those containing a-SiC as a main component are particularly preferable. When the surface layer is composed mainly of a-SiC, the amount of carbon is preferably in the range of 30 to 90 atom% with respect to the total amount of silicon atoms and carbon atoms.

In the present invention, it is preferable that the surface layer contains hydrogen atoms and / or halogen atoms. This is essential for compensating the dangling bonds of silicon atoms and improving the quality of the layer, especially the photoconductive property and the charge retention property. The content of hydrogen atoms is usually 30 to 70 atom%, preferably 35 to 65 atom%, and more preferably 40 to the total amount of constituent atoms.
Is about 60 atom%. The content of halogen atoms such as fluorine atoms is usually 0.01 to 15 atom%, preferably 0.1 to 10 atom%, more preferably 0.6 to 4 atom%.
It is atomic%. The photoconductor formed in the range of the content of hydrogen atom and / or halogen atom is far superior to the conventional one in practical use and can be applied sufficiently.

It is known that defects (mainly dangling bonds of silicon atoms and carbon atoms) existing in the surface layer adversely affect the characteristics as a photoreceptor for an image forming apparatus. For example, deterioration of charging characteristics due to injection of charges from the free surface into the photoconductive layer, fluctuations in charging characteristics due to changes in the surface structure under operating environments such as high humidity, and during corona charging or light irradiation. Occasionally, the photoconductive layer injects charges into the surface layer, and the defects are trapped in the defects in the surface layer to cause an afterimage phenomenon upon repeated use. However, by controlling the hydrogen content in the surface layer to 30 atomic% or more, defects in the surface layer are significantly reduced, and as a result, electrical characteristics and high-speed continuous usability are drastically improved compared to conventional ones. Can be achieved. However, if the hydrogen content in the surface layer exceeds 70 atomic%, the hardness of the surface layer decreases, and it becomes impossible to withstand repeated use. Therefore, controlling the hydrogen content in the surface layer within the above range is one of the very important factors in obtaining the desired electrophotographic properties that are remarkably excellent. The hydrogen content in the surface layer can be controlled by the flow rate of H ₂ gas, the support temperature, the discharge power, the gas pressure and the like. Further, by controlling the fluorine content in the surface layer to be in the range of 0.01 atomic% or more, it becomes possible to more effectively achieve the generation of the bond between silicon atoms and carbon atoms in the surface layer. Further, as a function of the fluorine atom in the surface layer, the breaking of the bond between the silicon atom and the carbon atom due to damage such as corona can be effectively prevented. However, if the fluorine content in the surface layer exceeds 15 atomic%, the effect of generating the bond between the silicon atom and the carbon atom in the surface layer and the effect of preventing the breaking of the bond between the silicon atom and the carbon atom are hardly recognized. . Furthermore, since excess fluorine atoms impede the mobility of carriers in the surface layer, the residual potential and the image memory become noticeable. Therefore, controlling the fluorine content in the surface layer within the above range,
It is one of the important factors in obtaining desired electrophotographic characteristics. The fluorine content in the surface layer is the same as H content as H content.
₂ Gas flow rate, support temperature, discharge power, gas pressure, etc.

As a material that can be used as a source gas for supplying Si used in the formation of the surface layer of the present invention, SiH
_{4, Si 2 H 6, Si} 3 H 8, Si 4 H 10 , etc. of the silicon hydride that may or gasified gas state (silanes) can be mentioned as being effectively used, further layer formation of readiness in handling SiH ₄ and Si ₂ H ₆ are preferable as the sheath from the viewpoint of good Si supply efficiency. In addition, these raw material gases for supplying Si may be added with H ₂ , He, Ar, and Ne as necessary.
May be used after being diluted with such a gas. Examples of substances that can be used as a raw material gas for supplying carbon include CH ₄ , C ₂ H ₆ , and C _3.
Gaseous or gasifiable hydrocarbons such as H ₈ and C ₄ H ₁₀ can be effectively used, and CH _{4 in} terms of easiness of handling during layer formation and good Si supply efficiency.
And C ₂ H ₆ are preferred. In addition, if necessary, the source gas for supplying C may be H ₂ , He, or A.
It may be diluted with a gas such as r or Ne before use. As a substance that can be used as a gas for supplying nitrogen or oxygen, N
H ₃ , NO, N ₂ O, NO ₂ , H ₂ O, O ₂ , CO, CO ₂ ,
Examples of compounds that can be effectively used include compounds in a gas state or gasifiable such as N ₂ . Also, these nitrogen
The raw material gas for oxygen supply may be H ₂ , He, A
It may be diluted with a gas such as r or Ne before use. Further, in order to make it easier to control the introduction ratio of hydrogen atoms introduced into the surface layer to be formed, hydrogen gas or a silicon compound gas containing hydrogen atoms is also added in a desired amount to these gases. It is preferable to mix and form a layer. Further, each gas may be mixed not only with a single kind but also with a plurality of kinds at a predetermined mixing ratio.

Effective source gases for supplying halogen atoms used in the formation of the surface layer of the present invention include halogen gas, halides, halogen-containing interhalogen compounds, halogen-substituted silane derivatives and the like. Gaseous or gasifiable halogen compounds are preferred. Further, a gaseous or gasifiable silicon hydride compound containing a halogen atom, which contains silicon atoms and a halogen atom as constituent elements, can also be cited as an effective one. Specific examples of the halogen compound that can be preferably used in the present invention include fluorine gas (F ₂ ), BrF, ClF, ClF ₃ , BrF ₃ and B.
Inter-halogen compounds such as rF ₅ , IF ₃ and IF ₇ can be mentioned. As a silicon compound containing a halogen atom, that is, a so-called silane derivative substituted with a halogen atom, silicon fluorides such as SiF ₄ and Si ₂ F ₆ can be cited as preferable examples. In order to control the amount of hydrogen atoms and / or halogen atoms contained in the surface layer, for example, the temperature of the support, the raw material used to contain hydrogen atoms and / or halogen atoms, and It is performed by controlling the introduction amount, discharge power, and the like. Carbon atoms, oxygen atoms, and nitrogen atoms are evenly and uniformly contained in the surface layer, but there may be a portion having a nonuniform distribution such that the content varies in the layer thickness direction of the surface layer.

Further, in the present invention, it is preferable that the surface layer contains atoms for controlling the conductivity, if necessary. The atoms that control the conductivity are contained in the surface layer in a uniformly distributed state, but there may be a part in which the atoms are contained in a non-uniformly distributed state in the layer thickness direction.

As the atom for controlling the conductivity, a semiconductor is used.
The so-called impurities in the body field can be mentioned,
Group IIIb atoms or n-type conduction characteristics that give p-type conduction characteristics
A group Vb atom that imparts a property can be used. III
The group b atoms include boron (B), aluminum (A
l), gallium (Ga), indium (In), tariu
(Tl), etc., and B, Al, and Ga are particularly preferable.
You. Group Vb atoms include phosphorus (P), arsenic (As),
There are antimony (Sb), bismuth (Bi), etc., especially
P and As are preferred. Content of atoms controlling conductivity
Is preferably 1 × 10^-3~ 1 × 10^ThreeAtomic ppm, better
1x10 is better^-2~ 5 × 10^TwoAtomic ppm, optimally 1 ×
10^-1~ 1 × 10^TwoIt is atomic ppm. Hara that controls conductivity
Child, eg, a group IIIb atom or a group Vb atom, structurally
Introduced into the group IIIb atom during layer formation
Gas of the starting material for introducing the group Vb atom
Other gas for forming the surface layer in the reaction vessel in the state
To be introduced with. Raw materials for introducing Group IIIb atoms
Or as a raw material for introducing a Group Vb atom
The gas is at room temperature and atmospheric pressure, or at least under the layer forming conditions.
It is desirable to adopt one that can be easily gasified. This
Raw materials for introducing Group IIIb atoms such as
For child introduction, B_TwoH₆, B_FourH_Ten, B_FiveH₉, B
_FiveH₁₁, B₆H_Ten, B₆H ₁₂, B₆H₁₄Borohydride, such as
BF_Three, BCl_Three, BBr_ThreeSuch as boron halides
You can In addition, AlCl_Three, GaCl_Three, Ga (CH
_Three)_Three, InCl_Three, TlCl_ThreeAnd the like.
Effectively used as a raw material for introducing a Group Vb atom
For introducing phosphorus atom, PH is_Three, P_TwoH_FourEtc. hydrogen
Phosphorus, PH_FourI, PF_Three, PF_Five, PCl_Three, PCl_Five, P
Br_Three, PBr_Five, PI_ThreeAnd phosphorus halides such as
You. Besides this, AsH_Three, AsF_Three, AsCl_Three, AsB
r_Three, AsF_Five, SbH_Three, SbF_Three, SbF_Five, SbC
l_Three, SbCl_Five, BiH_Three, BiCl_Three, BiBr_ThreeEtc.
Listed as effective starting materials for introducing Group Vb atoms
Can be Also, the atoms that control these conductivities
Introduce raw materials as needed, H_TwoOr / and to He
You may use it after diluting.

The layer thickness of the surface layer in the present invention is usually 0.01 to 3 μm, preferably 0.05 to 2 μm.
m, more preferably 0.1 to 1 μm. The layer thickness is 0.
When the thickness is less than 01 μm, the surface layer is lost due to abrasion or the like during use of the photoconductor, and when the thickness exceeds 3 μm, electrophotographic characteristics such as increase in residual potential are deteriorated.

The surface layer in the present invention is formed as follows so that the required characteristics can be provided as desired. That is, Si and C or / and N or / and O
And a substance containing H and / or X as constituent elements are structurally in the form of crystalline to amorphous depending on the formation conditions, and in terms of electrical properties, conductive to semiconducting and insulating. In order to exhibit a property and to exhibit a property from a photoconductive property to a non-photoconductive property, in the present invention, a desired compound is formed so that a compound having a desired property depending on the purpose is formed. The formation conditions are strictly selected according to the compound. For example, when the surface layer is provided mainly for the purpose of improving the pressure resistance, it is formed as a non-single-crystal material having a remarkable electrical insulating behavior in the use environment. Also,
When a surface layer is provided mainly for the purpose of improving continuous repeated use characteristics and use environment characteristics, the degree of electrical insulation described above is relaxed to some extent, and a non-single crystal material having some sensitivity to irradiation light. Formed as. Furthermore, in the charging mechanism according to the present invention, in order to prevent image deletion due to the low resistance of the surface layer, or to prevent the influence of residual potential, on the other hand, in order to improve the charging efficiency,
When forming the layer, it is preferable to appropriately control the resistance value thereof. In order to form a surface layer having properties capable of achieving the object of the present invention, the temperature of the support and the gas pressure in the reaction vessel are appropriately set according to the desired compound. The temperature (Ts) of the support is appropriately selected in accordance with the layer design, but is preferably 200 to 350 ° C, more preferably 230 to 330 ° C, most preferably 250 to 300 ° C.
Similarly, the gas pressure in the reaction vessel is appropriately selected in accordance with the layer design, but an optimum range is selected, and preferably 1 × 10 ^{−4 to} 10 To.
rr, more preferably 5 × 10 ^{−4 to} 5 Torr, optimally 1 ×
It is 10 ^{−3 to 1} Torr. In the present invention, the above-mentioned ranges are mentioned as desirable numerical ranges of the temperature of the support and the gas pressure for forming the surface layer, but these conditions are not usually independently determined independently, It is desirable to determine the optimum value on the basis of mutual and organic relationships so as to form a photoconductor having the characteristics of.

The surface layer of the present invention is formed under the condition that the input power per unit flow rate is 0.1 to 0.5 W / sccm. By forming the surface layer under these conditions, it is possible to obtain a surface layer that is resistant to abrasion and has excellent sensitivity.

Further, in the present invention, it is also possible to provide a blocking layer (lower surface layer) having a carbon atom / oxygen atom / nitrogen atom content lower than that of the surface layer between the photoconductive layer and the surface layer. It is effective for further improving the characteristics such as. Further, a region where the content of carbon atoms and / or oxygen atoms and / or nitrogen atoms changes so as to decrease toward the photoconductive layer may be provided between the surface layer and the photoconductive layer. Thereby, the adhesion between the surface layer and the photoconductive layer can be improved, and the influence of interference due to the reflection of light at the interface can be further reduced.

Charge Injection Blocking Layer of Photoreceptor In the photoreceptor for an image forming apparatus of the present invention, it has a function of blocking charge injection from the conductive support side between the conductive support and the photoconductive layer. It is more effective to provide the charge injection blocking layer. That is, the charge injection blocking layer, when the photosensitive layer undergoes a constant polarity charging treatment on its free surface,
It has a function of preventing charges from being injected from the support side to the photoconductive layer side, and does not exhibit such a function when subjected to a charging treatment of the opposite polarity. There is. In order to impart such a function, the charge injection blocking layer contains a relatively large number of atoms for controlling conductivity as compared with the photoconductive layer. The atoms that control the conductivity may be evenly distributed in the layer, or there may be a part that is evenly distributed in the layer thickness direction but is unevenly distributed. Good. When the distribution concentration is non-uniform, it is preferable that the compound be contained so as to be distributed more on the support side. However, in any case, it is desirable that the content be uniformly distributed in the in-plane direction parallel to the surface of the support from the viewpoint of achieving uniform properties in the in-plane direction.

In the present invention, it is contained in the charge injection blocking layer.
In the field of semiconductors, atoms that control conductivity are
, So-called impurities, p-type conduction characteristics
Group IIIb atoms that give
Group Vb atoms can be used. As a group IIIb atom
For, boron (B), aluminum (Al), gallium
(Ga), indium (In), thallium (Tl), etc.
Yes, B, Al, and Ga are particularly preferable. Group Vb Hara
As a child, phosphorus (P), arsenic (As), antimony (S)
b), bismuth (Bi), etc., and P and As are particularly preferable.
It is. The inclusion of atoms controlling conductivity in the charge injection blocking layer.
In terms of quantity, the objective of the present invention can be effectively achieved.
Is appropriately determined according to the desire, but is preferably 10
~ 1 × 10 ^FourAtomic ppm, more preferably 50 to 5 × 10^Three
Atomic ppm, optimally 1 x 10^Two~ 1 × 10^ThreeAtomic ppm
You.

Furthermore, the charge injection blocking layer contains at least one kind of carbon atom, nitrogen atom and oxygen atom, so that the charge injection blocking layer can be provided with an adhesive property with other layers provided in direct contact with the charge injection blocking layer. It can be improved even more. Carbon atoms contained in this charge injection blocking layer
Nitrogen atoms and oxygen atoms may be evenly distributed in the layer, or they may be contained evenly in the layer thickness direction, but there is a portion that is contained in a non-uniformly distributed state. Good. However, in any case, it is desirable that the content be uniformly distributed in the in-plane direction parallel to the surface of the support from the viewpoint of achieving uniform properties in the in-plane direction. The content of carbon atoms and / or nitrogen atoms and / or oxygen atoms contained in the entire region of the charge injection blocking layer in the present invention is appropriately determined so that the object of the present invention can be effectively achieved. In the case of one kind, as the amount thereof, in the case of two or more kinds, as the sum thereof, preferably 1 × 10 ⁻³ to 50 atom%, more preferably 5 × 10 ⁻³ to
It is 30 atomic%, optimally 1 × 10 ⁻² to 10 atomic%.
Further, the hydrogen atoms and / or halogen atoms contained in the charge injection blocking layer in the present invention compensate for dangling bonds existing in the layer and are effective in improving the film quality. The content of hydrogen atoms, halogen atoms or the sum of hydrogen atoms and halogen atoms in the charge injection blocking layer is preferably 1 to 50 atom%,
It is more preferably 5 to 40 atom%, and most preferably 10 to 30 atom%. The thickness of the charge injection blocking layer is preferably from 0.1 to 5 μm, more preferably from 0.3 to 4 μm, and most preferably from 0.5 to 5 from the viewpoint of obtaining desired electrophotographic characteristics and economical effects. It is 3 μm.

In the present invention, the charge injection blocking layer is formed.
Vacuum deposition similar to the method of forming the photoconductive layer described above.
It is desirable to adopt the law. Can achieve the objects of the present invention
Of a charge injection blocking layer having the following characteristics by vacuum deposition
To supply Si, as in the case of the photoconductive layer,
Gas and dilution gas mixing ratio, gas pressure in the reaction vessel, discharge
It is necessary to set the force and the temperature of the support appropriately.
You. H which is a dilution gas _TwoOr / and He flow rate is layered
The optimum range is selected according to the total, but Si supply
H for gas_TwoOr / and He, usually 1-2
0 times, preferably 3 to 15 times, optimally 5 to 10 times
Control the enclosure. The gas pressure inside the reaction vessel is also designed in the same way.
Therefore, the optimum range is selected as appropriate, but in the normal case 1 × 1
0^-Four-10 Torr, preferably 5 × 10^-Four~ 5Torr, optimal
Has 1 × 10^-3~ 1 Torr. The discharge power is also the same
The optimum range is selected according to the layer design.
Discharge power with respect to the flow rate of gas for supply is normally 1
~ 7 times, preferably 2 to 6 times, optimally 3 to 5 times
Set to. In addition, the temperature of the support depends on the layer design.
Therefore, the optimum range is appropriately selected, but preferably 200 to
350 ° C, more preferably 230-330 ° C, optimally
It is 250-300 degreeC. In the present invention, charge injection
Mixing ratio of diluent gas, gas pressure, release to form blocking layer
As mentioned above as the desired numerical range of electric power and support temperature.
Range, but the factors for forming these layers are common.
It is not usually decided independently and separately, but the desired characteristics.
Based on mutual and organic relationships to form a functional layer.
It is desirable to determine the optimum value of the formation factor of each layer based on
New

In addition, in the photoreceptor for an image forming apparatus of the present invention, at least aluminum atoms, silicon atoms, hydrogen atoms and / or halogen atoms are unevenly distributed in the layer thickness direction on the support side of the photosensitive layer. It is desirable to have the layer area contained in the state. In the image forming apparatus photoreceptor of the present invention, for the purpose of further improving the adhesion between the support and the photoconductive layer or the charge injection blocking layer, for example, Si ₃ N ₄ , SiO ₂ , An adhesion layer made of an amorphous material containing SiO or a silicon atom as a base and containing a hydrogen atom and / or a halogen atom and a carbon atom and / or an oxygen atom and / or a nitrogen atom may be provided. Further, as described above, a light absorbing layer for preventing the generation of an interference pattern due to light reflected from the support may be provided.

Method and Device for Forming Photosensitive Layer Next, a device for forming the photosensitive layer and a method for forming the photosensitive layer will be described. FIG. 4 shows a high frequency plasma CVD method using the RF band as a power source frequency (hereinafter referred to as “RF-PCV”).
D ". FIG. 3 is a schematic configuration diagram illustrating an example of an apparatus for manufacturing a photoconductor for an image forming apparatus according to FIG. The structure of the manufacturing apparatus shown in FIG. 4 is as follows. This device is roughly divided into a deposition device (4100), a source gas supply device (4200), and an exhaust device (not shown) for reducing the pressure inside the reaction container (4111). A cylindrical support (4112), a support heating heater (4113), and a source gas introduction pipe (4114) are installed in the reaction vessel in the deposition apparatus, and a high-frequency matching box (4115) is further connected. ing.

The source gas supply device (4200) is made of SiH._Four,
GeH_Four, H_Two, CH_Four, B_TwoH₆, PH _ThreeSource gas of
Valve (4221-4226), valve (4231-4236, 4241-424
6, 4251-4256) and mass flow controller (4211
~ 4216) and each source gas cylinder is an auxiliary valve.
Introduction of raw material gas into the reaction vessel (4111) through the tube (4260)
It is connected to the pipe (4114).

Deposition film (photosensitive layer) using such an apparatus
Can be formed, for example, as follows. First, the cylindrical support (4112) is installed in the reaction vessel (4111), and the inside of the reaction vessel is evacuated by an exhaust device (not shown) (for example, a vacuum pump). Then, a heater for heating the support (41
By 13), the temperature of the cylindrical support is controlled to a predetermined temperature of 200 to 350 ° C. A gas cylinder valve (4231 to 423) is used to flow the raw material gas for forming the deposited film into the reaction vessel.
6) Confirm that the leak valve (4117) of the reaction vessel is closed, and that the inflow valves (4241-4246), outflow valves (4251-4256) and auxiliary valve (4260) are open. After confirming this, first open the main valve (4118) to evacuate the reaction vessel and the gas pipe. Next, when the reading of the vacuum gauge (4119) reaches about 5 × 10 ⁻⁶ Torr, the auxiliary valve and the outflow valve are closed. After that, each gas was introduced from the gas pump by opening the valve (4231-4236), and each gas pressure was adjusted to 2 Kg / cm by the pressure regulator (4261-4266).
Adjust to ² . Next, gradually open the inflow valves (4241 to 4246) to let each gas flow through the mass flow controller (4211
~ 4216) to introduce.

After the preparation for film formation is completed as described above, each layer is formed by the following procedure. When the cylindrical support reaches a predetermined temperature, gradually open the necessary ones of the outflow valves (4251 to 4256) and the auxiliary valve (4260),
A predetermined gas is introduced from the gas cylinder into the reaction vessel (4111) through the raw material gas introduction pipe. Next, the mass flow controllers (4211 to 4216) are used to adjust the raw material gases so that they have a predetermined flow rate. At that time, the pressure in the reaction vessel is 1
Adjust the opening of the main valve (4118) while observing the vacuum gauge so that the pressure becomes equal to or lower than Torr. When the internal pressure is stable, an RF power supply (not shown) having a frequency of 13.56 MHz is set to a desired power, and RF power is introduced into the reaction container through the high frequency matching box (4115) to cause glow discharge. The raw material gas introduced into the reaction vessel is decomposed by the discharge energy, and a deposited film containing silicon as a main component is formed on the cylindrical support. After the film having the desired film thickness is formed, the supply of the RF power is stopped, the outflow valve is closed to stop the gas from flowing into the reaction container, and the formation of the deposited film is completed. By repeating the same operation a plurality of times, a photosensitive layer having a desired multilayer structure is formed. Needless to say, all of the outflow valves other than the necessary gas are closed when forming each layer, and each gas remains in the reaction vessel and in the pipe from the outflow valve to the reaction vessel. To avoid this, close the outflow valve (4251 to 4256) and the auxiliary valve (42
60) is opened, the main valve (4118) is fully opened, and the system is temporarily evacuated to a high vacuum as needed.
Further, in order to make the film formation uniform, it is also effective to rotate the cylindrical support at a predetermined speed by a driving device (not shown) during the layer formation. Further, it goes without saying that the above-mentioned gas species and valve operation are changed according to the formation conditions of each layer.

Next, a method of manufacturing a photoreceptor for an image forming apparatus, which is formed by a high frequency plasma CVD (hereinafter referred to as "VHF-PCVD") method using a VHF band frequency as a power source, will be described. The deposition apparatus (4100) by the RF-PCVD method in the manufacturing apparatus shown in FIG. 4 is replaced with the deposition apparatus (5100) shown in FIG.
00) to obtain a photoconductor manufacturing apparatus for an image forming apparatus having the following configuration by the VHF-PCVD method. This device is roughly divided into a reaction container (5111) having a vacuum airtight structure and capable of reducing pressure, a source gas supply device (4200), and an exhaust device (not shown) for reducing the pressure inside the reaction container. Has been done. A cylindrical support (5112), a heater for heating the support (5113), a source gas introduction pipe (5114) and an electrode are installed in the reaction vessel (5111), and a high frequency matching box is connected to this electrode. . The inside of the reaction container is connected to a diffusion pump (not shown) through an exhaust pipe (5121). The raw material gas supply device (4200) uses SiH ₄ , GeH ₄ , H ₂ , CH ₄ , B ₂
Bomb H _6, PH ₃ or the like of the raw material gas (4221-4226) constructed from the valve (4231～4236,4241～4246,4251～4256) and mass flow controllers (4211 to 4216), a cylinder of each raw material gas valve It is connected to the source gas introduction pipe (5114) in the reaction vessel via (4260). Further, the space (5130) surrounded by the cylindrical support (5112) forms a discharge space.

VHF-PCVD using such an apparatus
The formation of the deposited film by the method can be performed as follows. First, a cylindrical support (5112) is installed in the reaction container, the cylindrical support is rotated by a drive unit (5120), and an exhaust pipe (e.g., a vacuum pump) is provided inside the reaction container by an exhaust device (not shown). Vent through 5121) and adjust the pressure in the reaction vessel to 1 × 10 ⁻⁷ Torr or less. Then, the temperature of the cylindrical support is heated and maintained at a predetermined temperature of 200 to 350 ° C. by the support heating heater (5113). To flow the raw material gas for forming the deposited film into the reaction container, make sure that the valves (4231 to 4236) of the gas cylinder and the leak valve (not shown) of the reaction container are closed. ~ 4246), the outflow valves (4251 to 4256) and the auxiliary valve (4260) are opened, and first the main valve (not shown) is opened to evacuate the reaction vessel and the gas pipe. Next, the reading of the vacuum gauge (not shown) is about 5
When the pressure reaches × 10 ^-6 Torr, the auxiliary valve (4260) and the outflow valve (4251 to 4256) are closed. Then, each gas is introduced from the gas cylinder (4221-4226) by opening the valve (4231-4236), and each gas pressure is adjusted to ² Kg / cm ² by the pressure regulator (4261-4266). Next, the inflow valve (4241
~ 4246) is gradually opened to introduce each gas into the mass flow controller (4211-4216).

After the preparation for film formation is completed as described above, each layer is formed on the cylindrical support (5112) as follows. When the cylindrical support reaches a predetermined temperature, the necessary ones of the outflow valves (4251 to 4256) and the auxiliary valve (4260) are gradually opened, and a predetermined gas is reacted from the gas cylinder through the raw material gas introduction pipe. Discharge space (51
Introduced in 30). Next, the mass flow controller adjusts each source gas so that it has a predetermined flow rate. At that time, the opening of the main valve (not shown) is adjusted while observing the vacuum gauge (not shown) so that the pressure in the discharge space becomes a predetermined pressure of 1 Torr or less. When the pressure is stable, a VHF power supply (not shown) with a frequency of 500 MHz is set to a desired power, and V is supplied to the discharge space through the matching box.
HF power is introduced to cause glow discharge. In this way, in the discharge space surrounded by the cylindrical support, the introduced source gas is excited by the discharge energy and dissociated, so that a predetermined deposited film is formed on the cylindrical support. At this time, in order to make the layer formation uniform, the support rotating motor (5120) is rotated at a desired rotation speed. After the desired film thickness is formed, the supply of VHF power is stopped, the outflow valve is closed to stop the gas from flowing into the reaction vessel, and the formation of the deposited film is completed. By repeating the same operation a plurality of times, a photosensitive layer having a desired multilayer structure is formed. Needless to say, all of the outflow valves other than the necessary gas are closed when forming each layer, and each gas is introduced into the reaction vessel or from the outflow valve (4251 to 4256) to the reaction vessel. Close the outflow valve (4251-4256) to avoid it remaining in the pipe,
If necessary, the auxiliary valve (4260) is opened, the main valve (not shown) is fully opened, and the system is temporarily evacuated to a high vacuum. It goes without saying that the above-mentioned gas species and valve operation are changed according to the formation conditions of each layer.

In any of the above-mentioned methods, the temperature of the support during the formation of the deposited film is appropriately 200 to 350 ° C.,
Preferably 230-330 ° C, more preferably 250-330 ° C.
300 ° C. The heating method of the support may be any heating element having a vacuum specification, and more specifically, electric resistance heating elements such as a wound heater, a plate heater, a ceramic heater of a sheath heater, a halogen lamp, an infrared lamp, etc. Examples of the heat radiation lamp include a heating element and a heating element using a heat exchange means with a liquid or gas as a heating medium. As the surface material of the heating means, metals such as stainless steel, nickel, aluminum and copper, ceramics, heat-resistant polymer resin and the like can be used. In addition to these, a method such as providing a container for heating other than the reaction container and heating and then transporting the support into the reaction container in a vacuum can be used.

The pressure in the discharge space is set especially at VHF-PCVD.
In the method, preferably 1 to 500 mTorr, more preferably 3 to 300 mTorr, most preferably 5 to 100 mTorr.
It is.

In the VHF-PCVD method, the electrode provided in the discharge space may have any size and shape as long as the discharge is not disturbed, but in practice, the diameter is 1 mm to 10 mm.
A cylindrical shape of cm is preferable. At this time, the length of the electrode can be arbitrarily set as long as the electric field is uniformly applied to the support.
Any material may be used as the material of the electrode as long as it has a conductive surface, such as stainless steel or Al / Cr.
・ Mo ・ Au ・ In ・ Nb ・ Te ・ V ・ Ti ・ Pt ・ P
Metals such as b · Fe, alloys thereof, or glass / ceramic / plastic whose surface is subjected to conductive treatment can be usually used.

[0081]

EXAMPLES The present invention will be further described below with reference to experimental examples and examples, but the present invention is not limited thereto.

Experimental Example 1 Using the photoconductor manufacturing apparatus for an image forming apparatus by the RF-PQVD method shown in FIG. A photoconductive layer and a surface layer were sequentially formed to manufacture a photoreceptor for an image forming apparatus. At that time, various photoreceptors were prepared by changing the flow rates of SiH ₄ and CH ₄ and the discharge power of the surface layer based on the conditions shown in Table 1.

[0083]

[Table 1]

Image scratches and sensitivities were evaluated for the various photoconductors produced. For the evaluation of image scratches, a load of 10 to 100 g is applied to a diamond stylus φ0.1 mm, and a scratch test of the photoconductor is performed at a feed speed of 50 mm / s. The scratches on the image were observed. The maximum load (g) at which no scratch appears on the image was used as an index of scratch susceptibility (scratch rank). The sensitivity was determined by adjusting the light source so that a normal image was produced and measuring the amount of light and the developing potential at that time (unit: [V / lux · sec]). These results are shown in FIG.

As is clear from FIG. 6, it was found that scratches were less likely to occur as the applied voltage per unit flow rate was increased. At the same time, since the sensitivity tends to decrease, the applied voltage per unit flow rate of the surface layer is 0.1 to 0.
It can be seen that it is effective to use in the range of 5 sccm.

Experimental Example 2 A photoconductor for an image forming apparatus was prepared in the same manner as in Experimental Example 1 except that an intermediate layer having a thickness of 1 μm and having the same characteristics as the photoconductive layer was formed between the photoconductive layer and the surface layer. It was made. At this time, the discharge power and the gas flow rate were adjusted to change the film formation rate, and various photoconductors having different Eu or DOS of the photoconductive layer were produced. Note that DOS when Eu is changed is 1 × 10 ¹⁵
Eu when the cm ^-3 and DOS were changed was set to 55 meV.

The temperature characteristics, optical memory (memory rank) and image deletion (image deletion rank) of the obtained photoreceptor were evaluated. Regarding the temperature characteristics, the potential at a high temperature (40 ° C.) of the photosensitive member was set to 440 V, and the potential when the temperature was set to a low temperature (30 ° C.) was obtained, and the change in the potential with respect to the temperature change was evaluated. For the memory rank, a ghost chart was displayed and the density differences appearing on the chart were ranked.
This rank is 1 when there is almost no difference in density.
In the following, the numerical value was increased as the density difference increased. The image flow was ranked using the image flow chart to character and line sharpness.

The results of the above evaluations are shown in FIGS. The characteristic energy at the tail of the exponential function (Eu) obtained from the subband gap optical absorption spectrum is 50 to 60 meV, and the density of localized states (DOS) is 1 × 10 ¹⁴ to 1 × 10 ¹⁶ cm ^−3.
Particularly good results were obtained in the range of.

Further, the optical band gap (Eg) = 1.
With respect to the photoconductors at 72 eV and 1.78 eV, scratches were evaluated in the same manner as in Experimental Example 1. In Table 2, the results are summarized together with the evaluation of the photoconductor on which the intermediate layer was not formed. In Table 2, those in which scratches could not be confirmed on the image were marked with "⊚", those with slight scratches were marked with "△", and those with obvious scratches on the image were marked with "x". A photoreceptor having an intermediate layer and Eg = 1.72 eV exhibited the most excellent effect.

The photoconductors 1 and 2 were produced under the condition that the discharge power of the surface layer in Table 1 was 200 W, and the intermediate layers having Eg of 1.72 eV and 1.78 eV were formed, respectively. The photoconductor 3 was produced under the condition that the discharge power of the surface layer in Table 1 was 200 W.

[0091]

[Table 2]

Experimental Example 3 Photoreceptors (Photoreceptor 1 and Photoreceptor 3) shown in Table 2 in Experimental Example 2
Was set in the same image forming apparatus as in Experimental Example 1 to form an image, and the change in the scratch rank with respect to the temperature of the photoconductor was evaluated. The scratch rank was evaluated as 1 in the scratch test.
A load of 0 to 200 g was applied, and the maximum load at which scratches did not appear on the image at the time of image formation was ranked. A conventional corona charger or a contact charging system was used for the charging device.

The results are shown in FIG. When the contact charging method was used and the temperature of the photoconductor was above room temperature and within the range of 25 to 30 ° C., scratches were difficult to appear on the image.

Example 1 A photoconductor for an image forming apparatus was manufactured under the conditions shown in Table 3 using the manufacturing apparatus shown in FIG. Eu of the photoconductive layer at this time,
DOS and Eg are 55 meV and 2 × 10 ¹⁵ cm, respectively
^-3 , and 1.72 eV.

A magnetic brush composed of a multipolar magnetic body having 12 magnetic poles and a magnetic brush layer made of the same magnetic powder as in Experimental Example 1 was prepared as a charging member. The resistance of this charging member was 5 × 10 ⁸ Ωcm.

This charging member and the above-mentioned photosensitive member were mounted on the image forming apparatus shown in FIG. 1, and the voltage applied to the charging member was set to 60.
0 Vdc, process speed is 250 mm / sec, and the charging member is rotated in the same direction so that the peripheral speed ratio is 150% at the contact surface with the photoconductor (the contact surfaces move in opposite directions). ). The temperature of the photoconductor was controlled at 28 ° C.

In the same manner as in Experimental Example 1, after carrying out a scratch test by applying a load of 100 g, image formation was carried out.
A good image was obtained without any scratches on the image.

[0098]

[Table 3]

Example 2 The same evaluation as in Example 1 was carried out using the charging member of the bristle brush made of carbon ferrite and the photoreceptor of Example 1. As a result, a good image was obtained without any scratches on the image.

Example 3 A photoreceptor was prepared in the same manner as in Example 1 except for the conditions shown in Table 4, and the same evaluation as in Example 1 was carried out. As a result, a good image was obtained without any scratches on the image.

[0101]

[Table 4]

Example 4 The same evaluation as in Example 1 was performed, except that an image forming apparatus having a roller-type drum heater inside and a roller-contact type cooling device outside was used as shown in FIG. As a result, a good image was obtained without any scratches on the image.

[0103]

As is apparent from the above description, according to the present invention, it is possible to obtain a durable photoconductor for an image forming apparatus which is hard to be scratched and worn, and to obtain an image even if the photoconductor is scratched. It is possible to provide a maintenance-free image forming apparatus in which the image quality does not deteriorate even when used for a long period of time because scratches can be made less likely to appear.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of an image forming apparatus of the present invention.

FIG. 2 is a schematic configuration diagram of an embodiment of an image forming apparatus of the present invention.

FIG. 3 is an explanatory diagram of a layer structure of a photoconductor for an image forming apparatus of the present invention.

FIG. 4 is a schematic configuration diagram of an apparatus for manufacturing a photoconductor for an image forming apparatus of the present invention.

FIG. 5 is a schematic configuration diagram of a main part of a manufacturing apparatus of a photoconductor for an image forming apparatus of the present invention.

FIG. 6 is a diagram showing the relationship between the applied power when the surface layer of the photoreceptor for an image forming apparatus is formed, the scratch rank on the image, and the sensitivity.

FIG. 7 is a diagram showing the relationship between the characteristic energy of the exponential function tail and the temperature characteristic obtained from the sub-bandgap light absorption spectrum of the photoreceptor for an image forming apparatus.

FIG. 8 is a diagram showing a relationship between a localized density of states of a photoconductor for an image forming apparatus and an optical memory (memory rank).

FIG. 9 is a relationship diagram between the characteristic energy of the exponential function skirt obtained from the sub-bandgap light absorption spectrum of the photoconductor for an image forming apparatus and the image flow.

FIG. 10 is a relationship diagram between the surface temperature of the photoconductor for an image forming apparatus of the present invention and the scratch rank on the image.

FIG. 11 is a schematic configuration diagram of a conventional contact charging type image forming apparatus.

FIG. 12 is a schematic configuration diagram of a conventional contact charging type image forming apparatus using a magnetic brush.

[Explanation of symbols]

101, 201, 1101, 1201 photoconductors (photosensitive drums) 102, 202, 1102, 1202 charging members 102a, 202a, 1202a multi-pole magnetic bodies 102b, 202b, 1202b magnetic brush layers 103, 203, 1103, 1203 high-voltage power supply 104, 204, 1104, 1204 Image exposure 105, 205, 1105, 1205 Developing device 106, 206, 1106, 1206 Transfer material 107, 207, 1107, 1207 Transfer roller 108, 208, 1108, 1208 Cleaner 109, 209 Cooling device 110, 210 Drum heater 111, 211 Pre-exposure 301 Support 302 Photosensitive layer 303 Photoconductive layer 304 Surface layer 305 Intermediate layer 306 Charge injection blocking layer 1102a Electrode 1102b Resistive layer 4100, 5100 Deposition device 111, 5111 Reaction container 4112, 5112 Cylindrical support 4113, 5113 Heater for heating support 4114, 5114 Raw material gas introduction pipe 4115 High frequency matching box 4116 Gas pipe 4117 Leak valve 4118 Main valve 4119 Vacuum gauge 4200 Raw material gas supply device 4211-4216 Mass flow controller 4221-4226 Material gas cylinder 4231-4236 Gas cylinder valve 4241-4246 Inflow valve 4251-4256 Outflow valve 4260 Auxiliary valve 4261-4266 Pressure adjuster 5120 Drive device 5121 Exhaust pipe 5130 Discharge space

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuya Karaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiroyuki Katagiri 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (6)

[Claims] 1. At least a multi-pole magnetic material and a magnetic powder are used.
A voltage is applied to a cylindrical charging member that carries an image of the magnetic powder.
Charge the charged body by bringing it into contact with the charged body that is the holding body.
An image forming apparatus that forms an electrostatic latent image on the charged body.
At this time, the member to be charged has at least a conductive support and a shield.
Hydrogen atom and / or halogen with recon atom as a host
Having photoconductivity consisting of non-single crystal material containing atoms
It is composed of a photoconductive layer and a surface layer having a charge retaining function.
A photoconductor for an image forming apparatus, wherein
The optical band gap near the surface layer is at least 1.
70-1.75 eV, sub-bandgap optical absorption spectrum
The characteristic energy of the exponential tail obtained from Toru is 50 ~
60 meV, localized density of states 1 × 10¹⁴~ 1 × 10 ¹⁶c
m^-3And the electric resistance value of the surface layer is 1 × 10^Ten
~ 1 × 10^FifteenΩcm, the surface layer per unit flow rate
An input voltage of 0.1 to 0.5 W / sccm
Characterized by a surface layer of morphus silicon
Image forming device. 2. The image forming apparatus according to claim 1, wherein an intermediate layer is provided between the photoconductive layer and the surface layer. 3. The image according to claim 1, further comprising: a means for cooling the charged body, wherein the surface temperature of the charged body can be controlled at room temperature or higher and in the range of 25 to 30 ° C. Forming equipment. 4. A photoconductive layer having at least a conductive support, a photoconductive layer made of a non-single-crystal material containing hydrogen atoms and / or halogen atoms having a silicon atom as a matrix, and a surface having a charge retaining function. And an optical bandgap of at least in the vicinity of the surface layer of the photoconductive layer in the photoconductor for an image forming apparatus including a layer of 1.70 to
1.75 eV, characteristic energy of exponential tail obtained from sub-bandgap optical absorption spectrum is 50 to 60 m
eV, the density of localized states is 1 × 10 ¹⁴ to 1 × 10 ¹⁶ cm ⁻³ , and the electric resistance value of the surface layer is 1 × 10 ¹⁰ to 1 ×.
10 ¹⁵ Ωcm, and the surface layer is an amorphous silicon-based surface layer formed with an input power per unit flow rate of 0.1 to 0.5 W / sccm. . 5. The photoconductor for an image forming apparatus according to claim 4, wherein an intermediate layer is provided between the photoconductive layer and the surface layer. 6. An image forming apparatus comprising the photoconductor for an image forming apparatus according to claim 4.