JPH1031344A - Electrifier and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make maintenance free by obtaining an image of high quality, without making the rotational speed of a conductive fur brush faster. SOLUTION: A photoreceptor drum 105 is electrified by a belt-like conductive fur brush 104 revolved in the axial direction of the photoreceptor drum 105. A contact electrifying member 100 using the conductive fur brush 104 is formed in such a manner that a magnetic brush layer 101 is flocked on a flexible sheet 102. A contact electrifying member 106 can be disposed over the entire length, so as to come into circular-arcuate contact with the periphery of the drum 105 or a cleaning device 107 can be provided on the belt-like contact electrifying member 100.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device using a conductive fur brush as a contact charging member of a voltage application type and an image forming apparatus having the charging device.

[0002]

[Prior art]

[Image Forming Apparatus] An image forming apparatus is widely used in addition to a conventional so-called copying machine for copying an original, as well as a computer which has been growing in demand in recent years and a printer as an output means of a word processor. With respect to such printers, not only conventional office use but also personal use has increased, so that economical efficiency such as low cost and maintenance free is emphasized.

Further, from the viewpoint of ecology, measures to reduce the amount of paper consumed, such as double-sided copying and use of recycled paper, to save energy by reducing power consumption, and to reduce the amount of ozone generated, are as important as economics. Sought in degrees.

A corona charger, which has been the mainstream of the conventional charging system in an image forming apparatus, generates a corona discharge by applying a high voltage of about 5 to 10 kV to a metal wire having a thickness of about 50 to 100 μm to generate an atmosphere. This is to impart charge to the opposing object by ionization. During the discharging process, the wires themselves absorb dirt, so that periodic cleaning and replacement are required. In addition, unnecessary ozone is generated with the corona discharge.

[0005] In addition to the above, there is a problem with the photoconductor heater in terms of energy saving. An electrophotographic photoreceptor used as a member to be charged in recent years is designed to have a high surface hardness to increase the number of printings, and is used for a long time. For this reason, a corona product is derived from the ozone repeatedly generated from the corona charger, and the surface of the photoreceptor becomes sensitive to humidity due to the influence of the ozone, so that moisture is easily adsorbed. This causes a lateral flow of charges on the surface of the photoreceptor, which causes a deterioration in image quality, which is called an image flow.

In order to prevent such image deletion, a method of removing moisture by heating with a heater as disclosed in Japanese Utility Model Publication No. 1-305205, and Japanese Patent Publication No.
Japanese Patent Application Laid-Open No. 61-100780 discloses a method of removing corona products by rubbing the surface of a photoreceptor with a brush formed by a magnet roller and a magnetic carrier as described in JP-A-38956. A method has been used in which the surface of the photoconductor is rubbed with an elastic roller as described to remove corona products.

Such a method of removing corona products by rubbing the surface of a photoconductor is used for an amorphous silicon photoconductor having extremely high hardness. It is not suitable for cost reduction.
In the method of removing water by heating with a heater, constant heating causes an increase in power consumption. The capacity of such a heater is not necessarily large, usually about 15 W to 80 W, but in most cases the power is always supplied even at night, and the power consumption per day is the power consumption of the entire image forming apparatus. As much as 5-15% of the volume.

Further, an external heater heating system, that is, Japanese Patent Application Laid-Open No. 59-111179 and Japanese Patent Application Laid-Open No. 62-2785.
Even in the heating method disclosed in Japanese Patent Publication No. 77-77, there is no disclosure about improvement of the image density unstable element due to the temperature fluctuation of the photoconductor.

It is known that the above-mentioned ozone, which is a cause of such image deletion, has an effect on people and living things around the image forming apparatus. I was Especially in the case of personal use, the amount of emitted ozone must be reduced as much as possible. As described above, it is required to greatly reduce the amount of ozone generated at the time of charging from the viewpoint of both economy and environment.

Under these circumstances, a new charging member, a charging device, a charging device with no or reduced amount of generated ozone as an image forming device, a dehumidifying device with low power consumption, and an image forming device equipped with these components have been developed. It has been demanded.

[Charging device] In order to solve the above problems,
Various charging devices have been proposed.

A contact charging device described in Japanese Patent Application Laid-Open No. 63-208878 is a device in which a charging member to which a voltage is applied is brought into contact with a member to be charged to charge a surface to be charged to a required potential. First, compared with the corona charging device widely used as a charging device, firstly, the applied voltage required to obtain a desired potential on the surface to be charged can be reduced. The amount of ozone generated in the process is extremely small, and the necessity of installing an ozone removal filter is eliminated; therefore, the configuration of the exhaust system of the apparatus is simplified,
Being maintenance-free, and thirdly, a corona product derived from ozone generated in the charging process adheres to the surface of the image carrier, for example, the surface of the photoreceptor, which is the surface to be charged,
Dehumidification by a heater that is performed throughout the day to prevent image flow due to surface low resistance caused by the surface of the photoreceptor becoming sensitive to humidity due to the influence of corona products and absorbing moisture easily Power consumption, such as night-time electricity,
It has advantages such as.

Therefore, contact charging devices having such advantages include, for example, electrophotographic image forming apparatuses (copiers, laser beam printers), and electrostatic recording type image forming apparatuses, such as photoconductors and dielectrics. As a means of charging a carrier and other charged objects, it has attracted attention as an alternative to a corona discharge device, and has been put to practical use.

Conventionally, as a contact charging device, a fixed charging member in the form of a blade or a sheet is brought into contact with a member to be charged.
It is well known that a bias is applied thereto to perform charging.

FIG. 8 shows an example in which a blade-shaped charging member is used. Reference numeral 801 denotes a drum-type electrophotographic photosensitive member (photosensitive drum), which is rotationally driven at a predetermined peripheral speed (process speed) in the clockwise direction of arrow A. 80
Reference numeral 2 denotes a contact charging member, which includes an electrode 802-1 and a resistance layer 802-2 formed on a charging surface thereof.

The electrode 802-1 is usually made of aluminum,
Metals such as aluminum alloy, brass, copper, iron, and stainless steel, and insulating materials such as resin and ceramic that have been subjected to conductive treatment are used. Then, as the conductive treatment, a metal is coated or a conductive paint is applied.

The resistance layer 802-2 is generally formed by dispersing a conductive filler such as titanium oxide, carbon powder, or metal powder in a resin such as polypropylene or polyethylene, or an elastomer such as silicon rubber or urethane rubber. Used.

The resistance layer 802-2 has a resistance value of 250.
1 × 10 ³ to 1 × 1 as measured by an MΩ tester manufactured by HIOKI (manufacturer) at an applied voltage of 1000 V
It is formed so as to have 0 ¹² Ωcm.

Reference numeral 803 denotes a power supply for applying a voltage to the contact charging member 802. The power supply 803 controls a vibration voltage Vac having a peak-to-peak voltage Vpp twice or more the charging start voltage of the photosensitive drum 801 and a DC voltage. A charging voltage (Vac + Vdc) on which Vdc is superimposed is applied to the electrode 802-1 of the contact charging member 802 to uniformly charge the surface (outer peripheral surface) of the photosensitive drum 801 that is driven to rotate in this state.

Further, an electrostatic latent image is formed on the photosensitive drum 801 by scanning with the laser beam printer light 805 whose intensity is modulated according to the image signal. This electrostatic latent image is visualized by a developing sleeve 806 coated with a developer (toner) to become a toner image, and then transferred onto a transfer material 807 as a recording medium by a transfer roller 8.
08 is transferred. Then, the transfer material 807 after the transfer of the toner image is output outside the apparatus main body after the toner image on the surface is fixed by a fixing device (not shown). On the other hand, the transfer residual toner remaining on the surface of the photosensitive drum 801 without being transferred onto the transfer material 807 is cleaned by the cleaning blade 8.
09, and is subjected to the next image formation.

However, the contact charging member 802 described above
According to the method, the photosensitive drum 801 and the contact charging member 802 come into direct contact with each other and rub against each other. Therefore, the contact charging member 802 is worn out over a long period of use, and requires periodic replacement. In recent years, amorphous silicon photoreceptors that have begun to be widely used in image forming apparatuses have a semi-permanent life, and replacement of the contact charging member 802 impedes maintenance-free operation of the apparatus, and improvement is strongly demanded. .

As a solution to this problem, among various measures for improving the contact charging member, as disclosed in Japanese Patent Application Laid-Open No. S59-133569, a magnetic material and a carrier such as a magnetic powder or a magnetic particle (hereinafter referred to as a “charge carrier”) have been proposed. )), A new type of mechanism has been proposed in which a magnetic brush-shaped contact charging member provided with a photosensitive drum contacts a photosensitive drum to apply a charge.

FIGS. 9A and 9B show an example. 9A is a side view of the photosensitive drum 901 and the contact charging member 902, and FIG. 9B is a front view of the contact charging member 902. The photosensitive drum 901 is driven to rotate in a clockwise direction indicated by an arrow A at a predetermined peripheral speed (process speed). The contact charging member 902 includes a multipolar magnetic body 902-2,
A magnetic brush layer 902-1 formed of magnetic powder is provided on the charged surface (surface).

The multipolar magnetic body 902-2 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.

The magnetic brush layer 902-1 is generally made of magnetic iron oxide (ferrite) powder, magnet powder, a well-known magnetic toner material, or the like.

Contact charging member 9 constituted by these
It is desirable that the resistance value of 02 is appropriately selected according to the environment in which it is used, high charging efficiency, the withstand voltage characteristics of the surface layer of the photosensitive drum 901 and the like.

Photosensitive drum 901 and multipolar magnetic body 902-2
Is the contact width (hereinafter, “charging nip”) at which the magnetic brush layer 902-1 contacts the surface of the photosensitive drum 901.
) Must be stably set at a certain distance. This distance is 50-2000μ
m is preferable, and more preferably 100 to 1000.
μm.

Reference numeral 903 denotes a power supply for applying a voltage to the contact charging member 902. The DC voltage Vdc is supplied from the power supply 903 to the multipolar magnetic body 902-2 and the magnetic brush layer 902-1.
And the outer peripheral surface (surface) of the photosensitive drum 901 being driven to rotate is uniformly charged.

Further, an electrostatic latent image is formed on the photosensitive drum 901 by scanning with the laser beam printer light 905 whose intensity is modulated according to the image signal. This electrostatic latent image is visualized as a toner image by a developing sleeve 906 coated with a developer (toner). After that, the toner image is transferred onto the transfer material 907 by the transfer roller 90.
8 is transferred. Transfer material 90 after transfer of toner image
7 is output outside the apparatus main body after the toner image on the surface is fixed by a fixing device (not shown). On the other hand, the transfer drum remaining on the surface of the photosensitive drum 901 that has not been transferred to the transfer material 907 is removed by the cleaning blade 909, and is used for the next image formation.

According to the above-mentioned method using the contact charging member 902, characteristics such as contact property and frictional property between the photosensitive drum 901 and the contact charging member 902 are improved, and remarkable improvement such as mechanical abrasion against durability deterioration is achieved. Was planned.

Recently, a contact charging member using a fur brush has also been used. This is achieved, for example, by dispersing a conductive material on a roller-like electrode, a contact having conductivity, i.e., a plated metal brush or fiber brush, and bringing the conductive brush into contact with the photosensitive drum to reduce the charge. Is what you do.

[Photoconductor] [Organic photoconductor (OPC)] In recent years, various organic photoconductor materials have been developed as photoconductor materials for electrophotographic photoconductors.
In particular, a function-separated type photoconductor in which a charge generation layer and a charge transport layer are laminated has already been put to practical use and mounted on an image forming apparatus such as a copying machine or a laser beam printer.

However, one of the major drawbacks of these photoconductors is that their durability is generally low. The durability is roughly classified into durability of electrophotographic physical properties such as sensitivity, residual potential, charging ability and image blur, and mechanical durability such as abrasion and scratches on the surface of the photoreceptor due to rubbing. Each of these factors is a major factor in determining the life of the photoconductor.

Of these, the durability of the electrophotographic physical properties, particularly the image blur, relates to ozone generated from a corona charger,
It is known that the cause is that the charge transporting substance contained in the surface layer of the photoreceptor is deteriorated by an active substance such as NOx.

On the other hand, the mechanical durability is known to be caused by physical contact of a photosensitive member with a cleaning member such as a blade or a roller, paper and toner, and rubbing. .

In order to improve the durability of the electrophotographic physical properties, it is important to use a charge transporting substance which is not easily deteriorated by an active substance such as ozone or NOx, and it is necessary to select a charge transporting substance having a high oxidation potential. It has been known.
Also, in order to increase the mechanical durability of the other, in order to withstand rubbing by paper or a cleaning member, the surface lubricity is increased to reduce abrasion, and to prevent toner filming fusion and the like. It is important to improve the releasability of the surface, and it is known that a lubricant such as a fluororesin powder, fluorinated graphite, or a polyolefin resin powder is blended in the surface layer. However, when the abrasion is significantly reduced, a hygroscopic substance generated by an active substance such as ozone or NOx accumulates on the surface of the photoreceptor, and as a result, the surface resistance decreases and the surface charge moves in the lateral direction. There is a problem that [Amorphous silicon-based photoreceptor (a-Si)] As a photoconductive material for forming a photosensitive layer in an electrophotographic photoreceptor, it has a high sensitivity and an SN ratio [photocurrent (Ip) / dark current (Id).
)] Is high, has an absorption spectrum suitable for the spectral characteristics of the electromagnetic wave to be irradiated, has a fast light response, has a desired dark resistance value, and is harmless to the human body when used. Is 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, in consideration of being used for copying in a large amount and for a long time, the image quality,
The long-term stability of the image density is also important.

As a photoconductive material exhibiting such excellent properties, hydrogenated amorphous silicon (hereinafter referred to as “a
—Si: H ”), for example,
Japanese Patent Application Laid-Open No. 5059 discloses an application as a photosensitive member for an image forming apparatus.

In general, such a photoreceptor for an image forming apparatus is prepared by heating a conductive support to 50 to 400 ° C. and depositing the conductive support on the conductive support by a vacuum deposition method, a sputtering method, an ion plating method, or the like. A photoconductive layer made of a-Si is formed by a film forming method such as a thermal CVD method, a photo CVD method, and a plasma CVD method. Among them, the plasma CVD method, that is,
A method in which a source gas is decomposed by direct current, high frequency or microwave glow discharge to form an a-Si deposited film on a conductive support has been put to practical use as a suitable method.

Japanese Patent Application Laid-Open No. 54-83746 discloses an image comprising a conductive support and an a-Si (hereinafter referred to as "a-Si: X") photoconductive layer containing a halogen atom as a constituent element. Photoconductors for forming apparatuses have been proposed.
In the above-mentioned publications, a-Si has a halogen atom of 1 to 1.
It is stated that by containing 40 atomic%, heat resistance is high and good electrical and optical characteristics can be obtained as a photoconductive layer of a photoconductor for an image forming apparatus.

Japanese Unexamined Patent Publication No. Sho 57-115556 discloses that a photoconductive member having a photoconductive layer composed of an a-Si deposited film has an electrical property such as a dark resistance value, a photosensitivity, and a photoresponsive property.
In order to improve the use environment characteristics such as optical and photoconductive properties and moisture resistance, as well as the stability over time, silicon atoms and carbon are deposited on a photoconductive layer composed of an amorphous material based on silicon atoms. A technique of providing a surface barrier layer made of a non-photoconductive amorphous material containing atoms is described.

Furthermore, Japanese Patent Application Laid-Open No. 60-67951 describes a technique relating to a photoconductor in which a light-transmitting insulating overcoat layer containing amorphous silicon, carbon, oxygen and fluorine is laminated. 62-1681
No. 61 describes a technique of using, as a surface layer, an amorphous material containing silicon atoms, carbon atoms, and 41 to 70 atomic% of hydrogen atoms as constituent elements.

[0042] Further, in JP-A-57-158650, hydrogen containing 10 to 40 atomic%, 0.2 absorption coefficient ratio of the absorption peak of 2100 cm ^-1 and 2000 cm ^-1 in the infrared absorption spectrum It is described that a photosensitive member for an image forming apparatus having high sensitivity and high resistance can be obtained by using a-Si: H of 1.7 for the photoconductive layer.

On the other hand, Japanese Unexamined Patent Publication No. Sho 60-95551 discloses that in order to improve the image quality of an amorphous silicon photoreceptor, the temperature near the surface of the photoreceptor is maintained at 30 to 40.degree. A technique is disclosed in which an image forming process such as transfer is performed to prevent a reduction in surface resistance due to the adsorption of moisture on the surface of a photoreceptor and an image deletion caused thereby.

These techniques have improved the electrical, optical, photoconductive and operating environment characteristics of the photoreceptor for an image forming apparatus, and the image quality accordingly.

[0045]

However, the magnetic particles of the voltage application type described above are brushed (contact charging member).
The following points can be cited as problems when the charging device used as the charging device is used as a charging unit for the image carrier.

In particular, when the rotation speed of the photosensitive member 901 is high, or when the potential difference between the charged portion (contact charging member) and the non-charged portion (charged member) is large, the durability of the contact charging member 902 is poor. Can be Charge carriers such as magnetic powder constituting the magnetic brush layer 902-1 move to the surface during rotation of the photoconductor 901 in a charging process or the like, and as a result, the charging efficiency is reduced and the photoconductor is not displayed on the image after development. A density difference can be seen in the rotation direction 901. In particular, in an image forming apparatus such as an amorphous silicon photoreceptor which is used at a high speed and has a very long life, the image quality is reduced due to the decrease in the charge carriers of the contact charging member 902, and the contact charging member 9
02 has to be maintained or replaced. Such a problem causes an increase in service cost, which hinders maintenance-free operation.

JP-A-59-133569 discloses a mechanism in which a cleaning blade 909 is provided downstream of the contact charging member 902 in the rotation direction of the photoconductor 901 to recapture the above-described charged carrier. However, there is a problem that maintenance-free operation is hindered as described above. In addition, the photosensitive member 90 whose surface hardness is not so high is particularly high.
In the case of No. 1, the surface of the photoconductor 901 is polished by the charge carrier attached to the developing sleeve 906, and the image quality may be deteriorated.

When a fur brush is used as the contact charging member, the maintenance interval can be extended without reducing the number of charge carriers, but hair-like charging unevenness of the fur brush occurs. It is necessary to rotate the fur brush in a reverse direction or at a high speed with respect to the member to be charged in order to eliminate the charging unevenness. Therefore, although the image quality can be improved by doing so, the fur brush or the member to be charged is improved. Result in shortening the life of the device.

Therefore, as a method of extending the life of the fur brush, for example, Japanese Patent Application Laid-Open No. Sho 59-228675 discloses a method in which a magnetic powder is mixed into fibers of a fur brush and a magnet is provided in a member to be charged. This discloses a technique for preventing set of the fur brush.

Japanese Patent Application Laid-Open No. Hei 5-241425 discloses that the toner or paper powder adhered to the surface of the photoreceptor is slid and moved to thereby stably charge the toner regardless of the presence or absence of toner or paper powder. A technique capable of realizing a state is disclosed.

However, even if these methods are used,
Since the fur brush is rotated at a high speed to improve the image quality, the fur brush and the member to be charged are worn due to friction, which hinders maintenance-free operation.

Therefore, when designing an image forming apparatus and an electrophotographic image forming method, it is required to improve the photoreceptor for the image forming apparatus from a comprehensive point of view such as electrophotographic physical properties and mechanical durability. I was

Accordingly, the present invention has been made to solve the above-mentioned problems, and it is intended to obtain a high-quality image without increasing the rotation speed of the contact charging member, and to improve the life of the contact charging member. It is an object of the present invention to provide a charging device and an image forming apparatus that extend the life of a member to be charged and extend the life of the member to be maintained.

[0054]

According to a first aspect of the present invention, there is provided a charging device according to the present invention.
The charging surface of the contact charging member to which a voltage is applied, which is configured to be charged by contacting the surface of the member to be charged,
The contact charging member is formed of a belt-shaped conductive fur brush.

According to a second aspect of the present invention, the conductive fur brush is formed by providing a magnetic brush layer on a belt-shaped flexible sheet.

According to a third aspect of the present invention, the conductive fur brush is stretched so as to orbit along the axial direction of the member to be charged.

According to a fourth aspect of the present invention, the conductive fur brush is stretched so as to move around a part of the member to be charged in a circumferential direction.

According to a fifth aspect of the present invention, the charging surface of the contact charging member to which a voltage is applied is charged by bringing the charging surface into contact with the surface of the member to be charged. Formed by an electrically conductive fur brush,
Further, the conductive fur brush is provided with cleaning means for removing dust.

According to a sixth aspect of the present invention, the conductive fur brush is formed by stretching a flexible sheet in a belt shape and providing a magnetic brush layer on the flexible sheet.

According to a seventh aspect of the present invention, the conductive fur brush is stretched so as to orbit along the axial direction of the member to be charged.

According to the present invention, the conductive fur brush is stretched so as to move around a part of the member to be charged in the circumferential direction.

According to a ninth aspect of the present invention, there is provided an image forming apparatus, comprising: a charging device for bringing a contact charging member to which a voltage is applied into contact so as to charge a member; and forming an electrostatic latent image on the member. An electrostatic latent image forming unit, a developing unit that visualizes the electrostatic latent image formed on the member to be charged, and a toner image formed on the member to be transferred by the developing unit onto a recording medium. And a transfer unit, wherein the charging device is provided with a contact charging member formed by a belt-shaped conductive fur brush.

According to a tenth aspect of the present invention, the conductive fur brush is formed by stretching a flexible sheet in a belt shape and providing a magnetic brush layer on the flexible sheet.

According to the eleventh aspect of the present invention, the conductive fur brush is stretched so as to move in the axial direction of the member to be charged.

According to a twelfth aspect of the present invention, the conductive fur brush is stretched so as to move around at one point in a circumferential direction of the member to be charged.

According to a thirteenth aspect of the present invention, there is provided the charging device according to any one of the first to eighth aspects, and an object to be charged which is charged by the charging device. A support, a photoconductive layer having photoconductive properties including a non-single-crystal material containing at least one of a hydrogen atom and a halogen atom based on a silicon atom, and a surface layer having a function of retaining electric charges. Wherein the photoconductive layer contains 10 to 30 atomic% of hydrogen, and has a characteristic energy of an exponential function tail obtained from a sub-bandgap light absorption spectrum at least in a portion where light is incident. 50 to 60 meV, and the local density of states below the conduction band edge is 1 × 10 ¹⁴ cm ⁻³ or more and less than 1 × 10 ¹⁶ cm ⁻³ .

The invention according to claim 14 is an electrophotographic photosensitive member, wherein the member to be charged has a conductive support, an organic photosensitive layer, and a surface layer containing charge-retaining particles.

[Operation] Based on the above configuration, the contact charging member is stretched along the member to be charged, and is formed by a belt-shaped conductive fur brush to which a voltage is applied. Then, by charging the charged object using the conductive fur brush, the contact width between the contact charging member and the charged object is increased. That is, the belt-shaped conductive fur brush is two to two times the roll-shaped fur brush.
The contact width can be tripled. As a result, a high-quality image can be easily obtained. In addition, the belt-shaped conductive fur brush can have a nip that is three to five times wider than a roll-shaped fur brush, and the density in the circumferential direction of the member to be charged increases. It is not necessary to rotate the brush at a high speed, and the life of the fur brush can be extended, and the life of the member to be charged can be significantly extended.

[0069]

Embodiments of the present invention will be described below in detail with reference to the drawings.

[Contact Charging Member] FIG. 1A shows a contact charging member 100 of the charging device according to the first embodiment of the present invention.
FIG. 3B is a perspective view showing a schematic configuration of FIG.
FIG. 4C is an enlarged front view showing a portion extracted and FIG. 4C is an enlarged front view showing a portion B extracted from FIG.
FIG. 9 is a perspective view illustrating a schematic configuration of a contact charging member 106 of a charging device according to a second embodiment of the present invention.

The belt-shaped contact charging member 100 is similar to that shown in FIG.
As shown in FIG. 1A, a drum-shaped electrophotographic photosensitive member (hereinafter, referred to as a “photosensitive drum”) 105 as a member to be charged is disposed along the axial direction of the photosensitive member, and as shown in FIG. A magnetic brush layer 101, a belt-shaped conductive brush support (flexible sheet) 102 on which the magnetic brush layer 101 is implanted, and a conductive core shaft 103 on which the brush support 102 is stretched; It has. Then, by the magnetic brush layer 101 and the brush support 102, FIG.
A conductive fur brush 104 is formed as shown in FIG. In this case, the gap between the brush support 102 and the photosensitive drum 105 is held by a spacer (not shown).

Further, the contact charging member 106 is provided as shown in FIG.
As shown in FIG. 1, the contact charging member 106 is disposed along the entire length of the photosensitive drum 105 so as to contact the peripheral surface of the photosensitive drum 105 in an arc shape. The configuration of the contact charging member 106 is shown in FIG. Magnetic brush layer 101 as well as contact charging member 100
, A brush support 102, and a core shaft 103 on which the brush support 102 is stretched. FIG. 1B shows an extracted and enlarged view of the portion C in FIG.

The photosensitive drum 105 and the brush support 102
In order to stably control the contact width (hereinafter referred to as “nip”) of the contact charging member 100 with respect to the photosensitive drum 105, the closest gap to the photosensitive drum 105 is stably maintained at a predetermined distance by an appropriate method such as a roller or a spacer. Need to be set. This distance is 5
The range is preferably 0 to 2000 μm, more preferably 1 to 2000 μm.
It is 00 to 1000 μm. In addition, a mechanism such as a blade may be provided for nip adjustment. The conductive fur brush 104 is obtained by mixing a conductive substance such as carbon into an organic fiber such as rayon or acrylic and adjusting the resistance value, or a fibrous conductive material such as carbon fiber or metal fiber. Is used.

The photosensitive drum 105 may be the same as the conventional one, but in the case of the present embodiment, a new photosensitive drum 105 described later is used.

In the present invention, in the contact charging members 100 and 106 using the conductive fur brush 104 as described above, the fur brush 104 is connected to the belt-shaped flexible sheet 10.
2, the contact width (nip) of the magnetic brush layer 101 is efficiently widened by implanting and configuring the magnetic brush layer 101,
A high-quality image can be obtained without rotating the fur brush 104 at high speed.

That is, when the nip portion between the brush support 102 and the photosensitive drum 105 is narrow, the fur pattern (thickness, number per unit area, state of the tip) of the fur brush 104 directly reflects the fur pattern. Occurs on the image. However, when the nip portion between the brush support 102 and the photosensitive drum 105 is positively widened as in the present invention, it is possible to prevent a phenomenon that the fur brush 104 has a fur pattern on an image. However, when only the magnetic carrier is used without using the fur brush 104 as the contact charging member, the number of magnetic carriers is reduced, which hinders maintenance-free operation.

Further, in the charging device of the present invention, it is not necessary to rotate the fur brush 104 at high speed, so that the fur brush 104 is not worn out due to friction or the like, so that the life can be extended and the photosensitive member can be extended. The service life of the drum 105 can be drastically extended, and maintenance-free operation becomes possible.

FIG. 1E is a perspective view showing a schematic configuration of a charging device according to a third embodiment of the present invention, and FIG. 1F is an extraction of a portion D in FIG. 1E. As shown in FIGS. 1E and 1F, a cleaning device 1 as a cleaning unit for removing toner and paper dust 109 adhering to the fur brush 104 as shown in FIGS.
07 is combined with the fur brush 104. The cleaning device 107 shown in FIGS.
Is attached to the contact charging member 100 shown in FIG. 1A, but can also be attached to the contact charging member 106 shown in FIG. Cleaning device 10
Reference numeral 7 denotes toner or paper powder 10 attached to the fur brush 104.
9 is scraped off by an insulating blade 108 and then completely removed by suction of air. That is, in the fur brush 104 of the present invention, as shown in FIG. 1E, the cleaning device 107 can be more easily attached than the magnetic brush and the roller-shaped fur brush.

Further, by using the cleaning device 107 together, the contact charging members 100 and 106 and the photosensitive drum 105 can have higher durability and can be maintenance-free.

As described in this embodiment, by using the contact charging devices 100 and 106 alone and by using the cleaning device 107 in combination with the contact charging members 100 and 106, the contact charging members 100 and 106 can be used.
6 and the photosensitive drum 105 can have high durability.

FIGS. 10A and 10B show an example.
Reference numeral 1001 denotes a drum-type electrophotographic photosensitive member (photosensitive drum) that is driven to rotate clockwise in the direction of arrow R1 at a predetermined peripheral speed (process speed).

The surface layer of the photosensitive drum 1001 is used to improve electrical characteristics such as charge holding ability and charging efficiency, and to prevent a so-called pinhole leak, which damages the surface layer due to a voltage. , Its resistance value is 1 × 1
It is preferably set to 0 ^{10 to} 5 × 10 ¹⁵ Ωcm. More preferably, it is 1 × 10 ¹² to 1 × 10 ¹⁴ Ωcm. The measurement of the resistance value in this case was performed by measuring with an applied voltage of 250 V to 1000 V using an MΩ tester manufactured by HIOKI (manufacturer).

Contact charging members 1002-a, 1002-b
The resistance value of the magnetic brush layer 1002-1 is HI to maintain good charging efficiency and to prevent pinholes.
250V-1 with MΩ tester manufactured by OKI (manufacturer)
In the measurement at an applied voltage of 000 V, 1 × 10 ³ to 1
It is preferable to have a resistance of × 10 ¹² Ωcm. More preferably, it is 1 × 10 ⁴ to 1 × 10 ⁸ Ωcm.

The photosensitive drum 1001 and the contact charging member 10
The nearest gap between the brush support 02-a and the brush support 1002-b is preferably set stably with a spacer (not shown) in the range of 50 to 2000 μm for nip control, and more preferably. It is 100 to 1000 μm. In addition, a mechanism such as a nip adjustment blade may be provided to stably set the closest gap.

Reference numeral 1003 denotes a power supply for applying a voltage to the contact charging member 1002-a, and a DC voltage Vdc is applied to the magnetic brush layer 1002-1 of the contact charging member 1002-a by the power supply 1003 to rotate the contact charging member 1002-a. The outer peripheral surface of the photosensitive drum 1001 is charged uniformly.

Further, an electrostatic latent image is formed on the photosensitive drum 1001 by scanning with laser beam printer light 1005 whose intensity is modulated according to the image signal.
This electrostatic latent image is developed by a developing sleeve 10 coated with a developer.
After being visualized by the reference numeral 06, the image is transferred onto a transfer material 1007 via a transfer roller 1008. Transfer material 1007
The transfer residual toner remaining on the photosensitive drum 1001 after transferring the toner image to the photosensitive drum 1001 is removed from the photosensitive drum 1001 by the cleaning blade 1009, and the transfer toner image is transferred to the transfer material 1007. After the image is fixed by the fixing device, the image is output outside the apparatus main body.

[Photoconductor] [Organic photoconductor (OPC)] In recent years, various organic photoconductor materials have been developed as photoconductor materials for electrophotographic photoconductors.
In particular, a function-separated type photoconductor in which a charge generation layer and a charge transport layer are laminated has already been put to practical use and mounted on an image forming apparatus such as a copying machine or a laser beam printer.

Hereinafter, an OPC photosensitive member, which is one form of a preferred photosensitive member charged by the contact charging member of the present invention, will be described. FIG. 11E is a schematic configuration diagram for explaining a layer configuration of the OPC photoconductor for an image forming apparatus.

An OP for a drum-shaped image forming apparatus shown in FIG.
C photoconductor (hereinafter simply referred to as “OPC photoconductor” as appropriate) 11
In No. 00, a photosensitive layer 1102 is provided on a cylindrical support (hereinafter simply referred to as “support”) 1101 for a photoconductor. The photosensitive layer 1102 is a photoconductive layer 110
3 (charge generation layer 1106 and charge transport layer 1107), and if necessary, a protective layer or surface layer 1104,
In addition, an intermediate layer is provided between the support 1101 and the charge generation layer 1106.

OPC photosensitive member 110 used in the present invention
0, that is, the surface layer 1104, the photoconductive layer 1103, and the intermediate layer
No. 04 needs to efficiently receive the charge injection from the contact charging member 100 and hold the charge effectively. The present applicants have proposed a material obtained by mixing a high-melting polyester resin and a cured resin, in particular, in the surface layer 1104, a charge-retaining particle such as a metal oxide such as SnO _{2 in} a mixed material of the high-melting polyester resin and the cured resin. It has been found that the dispersed materials act synergistically on the properties of the respective resin components and satisfy these conditions.

The surface layer 1104 and the photoconductive layer 1103 (the charge transport layer 1106 and the charge generation layer 110) of the OPC photosensitive member 1100 for an image forming apparatus as the above-described electrophotographic photosensitive member.
The resin component used for forming 7) will be described.

The polyester is a binding polymer of an acid component and an alcohol component, and is a polymer obtained by condensation of a dicarboxylic acid and a glycol or condensation of a compound having a hydroxy group and a carboxy group of hydroxybenzoic acid.

As the acid component, aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid; aliphatic dicarboxylic acids such as succinic acid, adipic acid and sebacic acid; alicyclic dicarboxylic acids such as hexahydroterephthalic acid; An oxycarboxylic acid such as ethoxybenzoic acid can be used.

As the glycol component, ethylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, cyclohexane dimethylol, polyethylene glycol, polypropylene glycol and the like can be used.

Incidentally, polyfunctional compounds such as pentaerythritol, lorimethylpropane, pyromellitic acid and their ester-forming derivatives may be copolymerized as long as the polyester resin is substantially linear.

As the polyester resin, a high melting point polyester resin is used.

The high melting polyester resin has an intrinsic viscosity of 0.4 in orthochlorophenol at 36 ° C.
dl / g or more, preferably 0.5 dl / g or more, more preferably 0.65 dl / g or more is used.

Preferred high melting point polyester resins include polyalkylene terephthalate resins. The polyalkylene terephthalate resin mainly comprises terephthalic acid as an acid component and alkylene glycol as a glycol component.

Specific examples thereof include polyethylene terephthalate (PET) mainly composed of a terephthalic acid component and an ethylene glycol component;
Polybutylene terephthalate (PBT) mainly composed of a 4-tetramethylene glycol (1,4-butylene glycol) component, polycyclohexyl dimethylene terephthalate (PCT) mainly composed of a terephthalic acid component and a cyclohexanedimethylol component, and the like. it can. As another preferable high molecular weight polyester resin, a polyalkylene naphthalate resin can be exemplified. The polyalkylene naphthalate resin is mainly composed of a naphthalenedicarboxylic acid component as an acid component and an alkylene glycol component as a glycol component. Specific examples thereof include polyethylene naphthalenedicarboxylic acid components and an ethylene glycol component. And phthalate (PEN).

The high melting point polyester resin has a melting point of preferably 160 ° C. or more, particularly preferably 200 ° C.
That's all.

In addition to the polyester resin, an acrylic resin may be used.

The binder is a bifunctional acrylic,
Hexafunctional acryl, phosphazene and the like are used.

It is considered that these resins have relatively high crystallinity, and the entanglement between the cured resin polymer chain and the high melting point polymer chain is uniform and dense, so that a highly durable surface layer can be formed. . In the case of a low-melting polyester resin or the like, since the crystallinity is low, there are portions where the degree of entanglement with the cured resin polymer chain is large and small, and the durability is considered to be poor.

As the surface layer 1104, a material in which a charge holding material such as SnO ₂ was dispersed was used. It is preferable to control the resistance value and the charging efficiency by using a dispersion amount appropriately selected according to use conditions and the like. [Amorphous silicon photoconductor (a-Si)]
An amorphous silicon photoconductor, which is one form of a preferable photoconductor charged by the contact charging member of the present invention, will be described.

The photoreceptor for an image forming apparatus comprises a conductive support and a photosensitive layer having a photoconductive layer made of a non-single-crystal material having silicon atoms as a base.
Containing about 30 atomic% of hydrogen and having a characteristic energy of 50 to 6 in an exponential tail (Urbuck tail) of an optical absorption spectrum.
0 meV and the density of localized states is 1 × 10 ¹⁴ to 1
It is characterized by being × 10 ¹⁶ cm ⁻³ .

The photoreceptor for an image forming apparatus designed to have the above-described configuration can solve all of the above-mentioned problems and has extremely excellent electrical, optical, photoconductive properties and image quality. Shows quality, durability and environmental characteristics of use.

Generally, in the band gap of a-Si: H, the tail level based on the structural disorder of the Si-Si bond and the dangling bond of Si are included.
Deep levels due to structural defects such as It is known that these levels act as trapping and recombination centers for electrons and holes, and cause deterioration of device characteristics.

As a method for measuring the state of a localized level in such a band gap, deep level spectroscopy, isothermal capacity transient spectroscopy, photothermal deflection spectroscopy, constant photocurrent method, and the like are generally used. . Above all, constant photocurrent method [Consta
nt Photocurrent Method: hereinafter referred to as “CPM”] is useful as a method for easily measuring a subgap light absorption spectrum based on the localized level of a-Si: H.

Applicants have determined the characteristic energy (hereinafter referred to as “Eu”) and the localized density of states (hereinafter referred to as “DOS”) of an exponential tail (Urbuck tail) obtained from an optical absorption spectrum measured by CPM. As a result of examining the correlation between the characteristics of the photosensitive member and the characteristics of the photosensitive member under various conditions, Eu and D
The inventors have found that the OS has a close relationship with 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 reduced when the photoreceptor is heated by a drum heater or the like is that the thermally excited carrier (hereinafter referred to as "thermally excited carrier") is attracted by the electric field at the time of charging, and the band at the bottom of the band is localized. It travels to the surface while repeatedly capturing and emitting levels and deep localized levels in the band gap,
It is possible to cancel the surface charge. At this time, the thermal excitation carrier that reaches the surface while passing through the charger has almost no effect on the reduction in charging ability,
The thermally excited carriers captured at the deep level reach the surface after passing through the charger, and are observed as a temperature characteristic because the surface charge is canceled. 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, it is necessary to suppress the generation of the thermally excited carrier in the operating temperature range of the photoconductor and to improve the running property of the thermally excited carrier in order to improve the temperature characteristics.

Further, the optical memory is generated by the optical carriers generated by the blank exposure or the image exposure being captured by the localized levels in the band gap and remaining in the photoconductive layer. That is, of 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 next charging or thereafter, and the potential of the light-irradiated portion becomes another. , Which results in shading on the image. Therefore, it is necessary to improve the traveling property of the optical carrier so that the optical carrier travels in one copying process without remaining in the photoconductive layer.

Therefore, by controlling Eu and DOS in a specific energy range, it is possible to suppress the generation of thermally excited carriers and to reduce the rate at which the thermally excited carriers and optical carriers are trapped in the localized levels. As a result, the traveling properties of the carrier (hereinafter referred to as "charge carrier") are significantly improved. As a result, the temperature characteristics of the photoconductor in the operating temperature range are dramatically improved, and at the same time, the occurrence of optical memory can be suppressed. Therefore, the stability of the photoconductor in the usage environment is improved, and the halftone becomes clearer. It is possible to stably obtain a high-quality image that comes out and has high resolution.

Hereinafter, the photoconductive member will be described in detail with reference to the drawings.

FIG. 11A is a schematic configuration diagram for explaining a layer configuration of an amorphous silicon photoreceptor for an image forming apparatus. An amorphous silicon photoconductor 1100 for an image forming apparatus shown in FIG. 11A has a photosensitive layer 1102 on a conductive support (support) 1101 for the photoconductor.
Is provided. This photosensitive layer 1102 is made of a-Si: H
Alternatively, the photoconductive layer 1103 is made of a-Si: X and has photoconductivity.

FIG. 11B is a schematic configuration diagram for explaining another layer configuration of a drum-shaped amorphous silicon photoconductor 1100 for an image forming apparatus (hereinafter, simply referred to as “photoconductor”). An amorphous silicon photosensitive member 1100 for an image forming apparatus shown in FIG. 11B has a photosensitive layer 1102 provided on a support 1101 for a photosensitive member. The photosensitive layer 1102 is made of a-Si: H or a-Si: H.
Photoconductive layer 1103 made of Si: X and having photoconductivity
And an amorphous silicon-based surface layer 1104.

FIG. 11C is a schematic configuration diagram for explaining another layer configuration of the amorphous silicon photosensitive member for an image forming apparatus of the present invention. An amorphous silicon photosensitive member 1100 for an image forming apparatus shown in FIG. 11C has a photosensitive layer 1102 provided on a support 1101 for a photosensitive member. The photosensitive layer 1102 is made of a-Si: H or a-Si: X and has photoconductivity.
03, an amorphous silicon-based surface layer 1104,
And an amorphous silicon-based charge injection blocking layer 1105.

FIG. 11D is a schematic configuration diagram for explaining still another layer configuration of the amorphous silicon photosensitive member for an image forming apparatus of the present invention. An amorphous silicon photoconductor 1100 for an image forming apparatus shown in FIG.
A photosensitive layer 110 is provided on a support 1101 for a photosensitive member.
2 are provided. This photosensitive layer 1102 is the photoconductive layer 1
A charge generation layer 1106 and a charge transport layer 1107 made of a-Si: H or a-Si: X constituting 103;
And an amorphous silicon-based surface layer 1104.

[Support] The support 1101 used for the above-mentioned photosensitive member 1100 may be either conductive or electrically insulating. Al, Cr, M as the conductive support
o, Au, In, Nb, Te, V, Ti, Pt, Pd,
Examples include metals such as Fe and alloys thereof, for example, stainless steel. Further, at least the surface of the electrically insulating support such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polystyrene, polyamide or the like on the side on which the photosensitive layer is formed of an electrically insulating support such as ceramic, ceramic, etc. A support subjected to a conductive treatment can also be used.

The shape of the support 1101 can be a cylindrical or plate-like endless belt having a smooth surface or an uneven surface, and the thickness thereof is as desired.
100 is appropriately determined, but if the photoreceptor 1100 for an image forming apparatus is required to have flexibility, the thickness should be as thin as possible within a range where the function as the support 1101 can be sufficiently exhibited. be able to. However,
The thickness of the support 1101 is usually 10 μm or more in terms of production, handling, mechanical strength, and the like.

In particular, when image recording is performed using coherent light such as laser light, the number of charged carriers is reduced in order to more effectively eliminate image defects due to so-called interference fringe patterns appearing in a visible image. May be provided on the surface of the support 1101 as long as the surface is substantially free of the following. Support 11
01 is provided on the surface of JP-A-60-1681.
Nos. 56, 60-178457 and 60-2
It is prepared by a known method described in, for example, US Pat.

As another method for more effectively eliminating image defects due to interference fringes when coherent light such as laser light is used, a support 1101 may be used as long as charge carriers are not substantially reduced. May be provided with a plurality of spherical trace depressions. That is, the support 1101
Has fine irregularities smaller than the resolving power required for the photosensitive member 1100 for an image forming apparatus, and the irregularities are caused by a plurality of spherical trace depressions. The unevenness due to the plurality of spherical trace depressions provided on the surface of the support 1101 is produced by a known method described in JP-A-61-231561.

Further, as another method for more effectively eliminating image defects due to interference fringe patterns when coherent light such as laser light is used, a method is provided in the photosensitive layer 1102 or below the photosensitive layer 1102. An interference prevention layer or a region such as a light absorption layer may be provided.

[Photoconductive layer] The photosensitive layer 1102 is formed on the support 1101 and, if necessary, on the undercoat layer (not shown).
The photoconductive layer 1103 constituting a part of the above is manufactured by appropriately setting numerical conditions of film forming parameters so as to obtain desired characteristics by a vacuum deposited film forming method. In particular,
For example, a glow discharge method (an AC discharge CVD method such as a low-frequency CVD method, a high-frequency CVD method, a microwave CVD method, or a DC discharge CVD method), a sputtering method, a vacuum deposition method, an ion plating method, an optical CVD method, heat C
It can be formed by various thin film deposition methods such as a VD method. These thin film deposition methods are appropriately selected and adopted depending on factors such as manufacturing conditions, the degree of load under capital investment, the manufacturing scale, and the characteristics desired for a photoconductor for an image forming apparatus to be manufactured. The glow discharge method, especially in the RF band or V
A high-frequency glow discharge method using a power supply frequency in the HF band is preferable.

In order to form the photoconductive layer 1103 by the glow discharge method, basically, a source gas for supplying Si capable of supplying silicon atoms (Si) and a source gas for supplying hydrogen atoms (H) are provided. And / or a source gas for X supply capable of supplying a halogen atom (X) is introduced in a desired gas state into a reaction vessel capable of reducing the pressure therein, thereby causing glow discharge in the reaction vessel. A-S on a predetermined support 1101 previously set at a predetermined position.
A photoconductive layer 1103 made of i,: H, a-Si,: X may be formed.

It is necessary that the photoconductive layer 1103 contains a hydrogen atom and / or a halogen atom, which compensates for dangling bonds of silicon atoms and improves the quality of the layer. In addition, it is indispensable for improving the charge retention characteristics. Therefore, the content of the hydrogen atom or the halogen atom, or the sum of the hydrogen atom and the halogen atom is preferably 10 to 30 atom%, more preferably 15 to 30 atom%, based on the sum of the silicon atom and the hydrogen atom and / or the halogen atom. It is desirably 25 atomic%.

Examples of substances that can serve as a Si supply gas include:
Silicon hydrides (silanes) in a gas state such as SiH ₄ , Si ₂ H ₆ , Si ₃ H ₈ , Si ₄ H ₁₀ or the like, which can be gasified, can be used effectively. SiH ₄ and Si ₂ H ₆ are preferred in terms of ease of handling at the time and good Si supply efficiency.

[0127] Then, a hydrogen atom structurally introduced in the photoconductive layer 1103 is formed, achieving such becomes easier to control the introduction rate of the hydrogen atoms, further H ₂ in these gases
It is necessary to form a layer by mixing a desired amount of He or a silicon compound gas containing a hydrogen atom.
Further, each gas is not limited to a single species, and a plurality of species may be mixed at a predetermined mixture ratio.

[0128] As a source gas for supplying a halogen atom, a gaseous or gasifiable halogen compound such as a halogen gas, a halide, an interhalogen compound containing halogen, or a silane derivative substituted with halogen is useful. Preferred. In addition, a gaseous silicon hydride compound containing a silicon atom and a halogen atom and containing a halogen atom that can be gasified can also be mentioned as an effective compound. In this case,
Specific examples of the halogen compound that can be suitably used include fluorine gas (F ₂ ), BrF, ClF, ClF ₃ , and BrF.
_3, BrF _5, it is possible to increase the interhalogen compounds such as IF _7. As a silicon compound containing a halogen atom, that is, a silane derivative substituted with a so-called halogen atom, specifically, for example, silicon fluoride such as SiF ₄ or Si ₂ F ₆ can be preferably mentioned.

In order to control the amount of hydrogen atoms and / or halogen atoms contained in the photoconductive layer 1103, for example, the temperature of the support 1101 and the raw material used to contain the hydrogen atoms and / or halogen atoms The amount to be introduced into the reaction vessel, the discharge power, etc. may be controlled.

It is preferable that the photoconductive layer 1103 contains atoms for controlling conductivity as necessary. The atoms that control the conductivity may be contained in the photoconductive layer 1103 in a state of being distributed uniformly and evenly, or there may be a part that is contained in the layer thickness direction in a non-uniform distribution state. Is also good.

Examples of the above-described atoms for controlling conductivity include so-called impurities in the field of semiconductors, and atoms belonging to Group IIIb of the Periodic Table which gives p-type conduction characteristics (hereinafter referred to as “Group IIIb atoms”). ) Or an atom belonging to the group Vb of the periodic table giving n-type conduction characteristics (hereinafter referred to as “Vb
Group atom).

Examples of Group IIIb atoms include boron (B), aluminum (Al), gallium (Ga),
There are indium (In) and thallium (Tl), and B, Al, and Ga are particularly preferable. Specific examples of group Vb atoms include phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi).
Is preferred.

The content of atoms for controlling conductivity contained in the photoconductive layer 1103 is preferably 1 × 10 ⁻² to
1 × 10 ⁴ atomic ppm, more preferably 5 × 10 ^{−2 to} 5 ×
10 ³ atoms ppm, optimally 1 × 10 ^-1 to 1 × 10 ³ atoms
It is desirable to use ppm.

Atoms controlling conductivity, for example, IIIb
To structurally introduce a group V atom or a group Vb atom,
In forming the layer, a source material for introducing a Group IIIb atom or a source material for introducing a Vb atom may be introduced in a gas state into the reaction vessel together with another gas for forming the photoconductive layer 1103. Good. As a raw material for introducing a Group IIIb atom or a raw material for introducing a Group Vb atom, those which are gaseous at ordinary temperature and normal pressure or which can be easily gasified at least under layer forming conditions are employed. Is desirable.

As a raw material for introducing a Group IIIb atom, specifically, for introducing a boron atom, B ₂ H
_{6, B 4 H 10, B} 5 H 9, B 5 H 11, B 6 H 10, B 6 H
_12, borohydride such as _{B 6 H 14, BF 3,} BC 13, BB
such as boron halides, such as r _3, and the like. In addition, AlCl ₃ , GaCl ₃ , Ga (CH ₃ ) ₃ , In
Cl ₃ and TlCl ₃ can also be mentioned.

Effectively used as a raw material for introducing a group Vb atom are PH ₃ and P ₂ for introducing a phosphorus atom.
Hydrogenated phosphorus such as H ₄ , PH ₄ I, PF ₃ , PF ₅ , PC
and phosphorus halides such as l ₃ , PCl ₅ , PBr ₃ , PBr ₅ and PI ₃ . In addition, AsH ₃ , AsF
₃ , AsCl ₃ , AsBr ₃ , AsF ₅ , SbH ₃ , S
bF ₃ , SbF ₃ , AbCl ₃ , SbCl ₅ , BiH
₃ , BiCl ₃ , BiBr _{3 and the} like can also be mentioned as effective starting materials for introducing a group Vb atom.

Further, these raw materials for introducing atoms for controlling conductivity may be diluted with H ₂ and / or He, if necessary.

It is also effective to make the photoconductive layer 1103 contain carbon atoms and / or oxygen atoms and / or nitrogen atoms. The content of the carbon atom and / or the oxygen atom and / or the nitrogen atom is preferably 1 × 10 ⁻⁵ to 10 atom%, more preferably 1 × 10 ⁵ %, based on the sum of silicon atom, carbon atom, oxygen atom and nitrogen atom. ^-4 to
8 at%, optimally 1 × 10 ^{−3 to} 5 at% is desirable.
The carbon atoms and / or oxygen atoms and / or nitrogen atoms may be uniformly contained in the photoconductive layer 1103 or may be non-uniform such that the content changes in the thickness direction of the photoconductive layer 1103. There may be a portion having an appropriate distribution.

The thickness of the photoconductive layer 1103 is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economic effects, and is preferably 20 to 50 μm.
More preferably 23 to 45 μm, optimally 25 to 40 μm
m is desirable.

In order to form the photoconductive layer 1103 having desired film characteristics, the mixing ratio of the gas for supplying Si and the diluent gas, the gas pressure in the reaction vessel, the discharge power, and the temperature of the support are appropriately set. is required.

[0141] The flow rate of H ₂ and / or He used as a dilution gas is properly selected within an optimum range in accordance with the layer design, to Si-feeding gas H ₂ and / or He
Is usually controlled in the range of 3 to 20 times, preferably 4 to 15 times, and most preferably 5 to 10 times.

The gas pressure in the reaction vessel is also appropriately selected in the same manner according to the layer design, but is usually 1 × 10 ^−4.
The pressure is preferably 10 to 10 Torr, more preferably 5 × 10 ^{−4 to} 5 Torr, and most preferably 1 × 10 ^{−3 to} 1 Torr.

Similarly, the optimum range of the discharge power is appropriately selected according to the layer design, but the discharge power to the flow rate of the gas for supplying Si is usually 2 to 7 times, preferably 2.times.
It is desirable to set the range to 5 to 6 times, optimally 3 to 5 times.

Further, the temperature of the support 1101 is appropriately selected in an optimum range according to the layer design, but is usually preferably 200 to 350 ° C., more preferably 230 to 3 ° C.
It is desirable that the temperature is 30 ° C, optimally 250 to 310 ° C.

Desirable numerical ranges of the temperature of the support and the gas pressure for forming the photoconductive layer include the above-mentioned ranges, but the conditions are not usually determined independently and independently, and the desired characteristics are obtained. It is desirable to determine the optimum value based on mutual and organic relationships to form the photoreceptor.

[Charge Injection Blocking Layer] In a photosensitive member for an image forming apparatus, a conductive support 1101 and a photoconductive layer 1103 are provided.
It is more effective to provide a charge injection blocking layer 1105 which has a function of blocking charge injection from the conductive support side. In other words, the charge injection blocking layer 1105 is a photosensitive layer 1102 that is subjected to a charging treatment with a fixed polarity on its free surface 110.
4a, has a function of preventing charge from being injected from the support side to the photoconductive layer side, and does not exhibit such a function when subjected to charging treatment of the opposite polarity. Has dependency. In order to provide such a function, the charge injection blocking layer 1105 contains a relatively large number of atoms for controlling conductivity as compared with the photoconductive layer 1103.

The atoms for controlling the conductivity contained in the charge injection element layer 1105 may be uniformly distributed throughout the layer, or may be uniformly distributed in the layer thickness direction. May be present in a non-uniformly distributed state. 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 each case, the support 1
In the in-plane direction parallel to the surface of the substrate 101, it is necessary to be uniformly contained in a uniform distribution from the viewpoint of making the characteristics in the in-plane direction uniform.

As the atoms for controlling the conductivity contained in the charge injection blocking layer 1105, there can be mentioned impurities in the field of semiconductors, the atoms belonging to Group III of the Periodic Table which gives p-type conductivity (hereinafter referred to as "atoms"). (Group III atoms) or an atom belonging to Group V of the periodic table that provides n-type conduction characteristics (hereinafter referred to as “Group V atoms”) can be used.

Examples of Group III atoms include boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Ta). In particular, B, Al, and Ga include It is suitable. Specific examples of Group V atoms include phosphorus (P), arsenic (As), and antimony (S
b) and bismuth (Bi), and P and As are particularly preferable.

The content of the atoms controlling the conductivity contained in the charge injection blocking layer 1105 is appropriately determined as desired so as to effectively achieve the polarity dependency, but is preferably 10 to 1 ×. 10 ⁴ atomic ppm, more preferably 50 to 5 × 10 ³ atomic ppm, and most preferably 1 × 10 ² to 1
It is preferably set to × 10 ³ atomic ppm.

Furthermore, by including at least one of carbon atoms, nitrogen atoms, and oxygen atoms in the charge injection blocking layer 1105, adhesion to another layer provided in direct contact with the charge injection blocking layer 1105 is achieved. The performance can be further improved.

The carbon atoms, nitrogen atoms, or oxygen atoms contained in the charge injection element layer 1105 may be uniformly distributed in the layer, or may be uniformly distributed in the layer thickness direction. However, there may be a portion which is contained in a state of being unevenly distributed. However, in any case, it is necessary to uniformly contain the particles in a uniform distribution in a plane parallel to the surface of the support from the viewpoint of making the characteristics uniform in the plane.

The content of carbon atoms and / or nitrogen atoms and / or oxygen atoms contained in the entire layer region of the charge injection blocking layer 1105 is appropriately determined so as to effectively achieve polarity dependency. , In the case of a kind,
In the case of two or more kinds, preferably 1 × 10
^-3 to 50 at%, more preferably 5 × 10 ⁻³ to 30 at%, and most preferably 1 × 10 ⁻² to 10 at%.

The hydrogen atoms and / or halogen atoms contained in the charge injection blocking layer 1105 compensate for dangling bonds existing in the layer, and are effective in improving the film quality. The content of hydrogen atoms or halogen atoms or the sum of hydrogen atoms and halogen atoms in the charge injection blocking layer 1105 is preferably 1 to 50 atomic%, more preferably 5 to 40 atomic%, and most preferably 10 to 40 atomic%. It is desirable to set it to 30 atomic%.

The thickness of the charge injection blocking layer 1105 is preferably 0.1 to 5 μm, and more preferably 0.3 from the viewpoints of obtaining desired electrophotographic characteristics and economic effects.
It is desirable that the thickness be 4 μm, most preferably 0.5 μm to 3 μm.

To form the charge injection blocking layer 1105,
A vacuum deposition method similar to the method for forming the photoconductive layer 1103 described above is employed.

In order to form the charge injection blocking layer 1105 having characteristics that can achieve the purpose of polarity dependence, the photoconductive layer 11
As in 03, it is necessary to appropriately set the mixing ratio between the Si supply gas and the dilution gas, the gas pressure in the reaction vessel, the discharge power, and the temperature of the support 1101.

The optimum flow rate of the diluent gas H ₂ and / or He is appropriately selected according to the layer design.
The H ₂ and / or He is usually 1 to 20 times, preferably 3 to 15 times, optimally 5 times the Si supply gas.
It is desirable to control to a range of 10 to 10 times.

Similarly, the optimum range of the gas pressure in the reaction vessel is appropriately selected in accordance with the layer design, but usually 1 × 10 ^−4.
The pressure is preferably 10 to 10 Torr, more preferably 5 × 10 ^{−4 to} 5 Torr, and most preferably 1 × 10 ^{−3 to} 1 Torr.

Similarly, the optimum range of the discharge power is appropriately selected in accordance with the layer design. The discharge power with respect to the flow rate of the Si supply gas is usually 1 to 7 times, preferably 2 to 6 times.
It is desirable to set it in the range of 2 times, optimally 3 to 5 times.

Further, the temperature of the support 1101 is appropriately selected in an optimum range according to the layer design, but is usually preferably 200 to 350 ° C., more preferably 230 to 3 ° C.
It is desirable that the temperature is 30 ° C, optimally 250 to 300 ° C.

Desirable numerical ranges of the mixing ratio of the diluent gas, the gas pressure, the discharge power, and the temperature of the support for forming the charge injection blocking layer 1105 are as described above.
These layering factors are usually not independently determined separately, but rather are defined as surface layers 110 having desired properties.
It is desirable to determine the optimum value of each layer forming factor based on mutual and organic relationships to form 4.

In addition, in the photoreceptor for an image forming apparatus, at least aluminum atom, silicon atom, hydrogen atom and / or
Alternatively, it is desirable to have a layer region containing halogen atoms in a non-uniform distribution state in the layer thickness direction.

In the photoreceptor for an image forming apparatus,
For the purpose of further improving the adhesion between the support 1101 and the photoconductive layer 1103 or the charge injection blocking layer 1105, for example, Si ₃ N ₄ , SiO ₂ , SiO, or a silicon atom as a base and a hydrogen atom And / or a halogen atom and a carbon atom and / or an oxygen atom and / or
Alternatively, an adhesion layer formed of an amorphous material containing nitrogen atoms may be provided. Further, as described above, the support 1
A light-absorbing layer may be provided to prevent the occurrence of an interference pattern due to the reflected light from 101.

Next, an apparatus and a film forming method for forming the photosensitive layer 1102 will be described in detail.

FIG. 2 is a schematic diagram showing an example of an apparatus for manufacturing a photosensitive member for an image forming apparatus by a high-frequency plasma CVD method (hereinafter, referred to as “RF-PCVD”) using an RF band as a power supply frequency. The configuration of the manufacturing apparatus shown in FIG. 2 is as follows.

This apparatus is roughly classified into a deposition apparatus 210
0, source gas supply device 2200, and reaction vessel 211
1 is constituted by an exhaust device (not shown) for reducing the pressure in the inside of the apparatus. A cylindrical support 2112 and a heater 211 for heating the support are provided in a reaction vessel 2111 in the deposition apparatus 2100.
3. A source gas introduction pipe 2114 is installed, and a high frequency matching box 2115 is connected.

The raw material gas supply device 2200 includes SiH ₄ ,
Cylinders 2221 to 2226 and valves 2231 to 22 for source gases such as GeH ₄ , H ₂ , CH ₄ , BH ₆ , and PH ₃
36, 2224 to 2246, 2251 to 2256, and mass flow controllers 2211 to 2216. The cylinders 2221 to 2226 for each source gas are connected to the source gas introduction pipe 2114 in the reaction vessel 2111 via the auxiliary valve 2260.

The formation of a deposited film using this apparatus can be performed, for example, as follows.

First, the cylindrical support 2112 is set in the reaction vessel 2111, and the inside of the reaction vessel 2111 is evacuated by an exhaust device (not shown) (for example, a vacuum pump). Subsequently, the cylindrical support 2112 is heated by the support heating heater 2113.
Is controlled to a predetermined temperature of 200 to 350 ° C.

The source gas for forming the deposited film is supplied to the reaction vessel 211.
1, the valves 2231 to 2237 of the gas cylinders 2221 to 2226 and the leak valve 2117 of the reaction vessel 2111 are closed, and the inflow valves 2241 to 2246 and the outflow valves 2251 to 2225 are checked.
After confirming that the auxiliary valve 2260 is open, the main valve 2118 is first opened and the reaction vessel 21 is opened.
11 and the gas pipe 2116 are evacuated.

Next, the reading of the vacuum gauge 2119 was about 5 × 10
^{When the} pressure reaches ^-6 Torr, the auxiliary valve 2260 and the outflow valves 2251 to 2256 are closed.

Thereafter, each gas is introduced from the gas cylinders 2221 to 2226 by opening the valves 2231 to 2236.
Each gas pressure is adjusted to 2 kg / by the pressure regulators 2261-2266.
adjusted to cm ^2. Next, the inflow valves 2241 to 2246
, Gradually open each gas to the mass flow controller 22.
11 to 2216.

After the preparation for film formation is completed as described above, each layer is formed in the following procedure.

When the temperature of the cylindrical support 2112 reaches a predetermined temperature, necessary ones of the outflow valves 2251 to 2256 and the auxiliary valve 2260 are gradually opened, and a predetermined gas is supplied from the gas cylinders 2221 to 2226 to the source gas introduction pipe 2114. Through the reaction vessel 2111. Next, each source gas is adjusted by the mass flow controllers 2211 to 2216 so as to have a predetermined flow rate. At this time, the opening of the main valve 2218 is adjusted while watching the vacuum gauge 2119 so that the pressure in the reaction vessel 2111 becomes a predetermined pressure of 1 Torr or less. When the internal pressure is stable,
An RF power source (not shown) having a frequency of 13.56 MHz is set to a desired power, and RF power is introduced into the reaction vessel 2111 through the high frequency matching box 2115 to generate glow discharge. The raw material gas introduced into the reaction vessel 2111 is decomposed by the discharge energy, and a deposited film mainly containing predetermined silicon is formed on the cylindrical support 2112. After the formation of the desired film thickness, the supply of the RF power is stopped, the outflow valve is closed, the flow of gas into the reaction vessel 2111 is stopped, and the formation of the deposited film is completed.

By repeating the same operation a plurality of times, a desired multilayer photosensitive layer 1102 is formed.

When forming each layer, it goes without saying that all the outflow valves other than the necessary gas are closed.
In order to avoid remaining in the piping from the outflow valves 2251 to 2256 to the reaction vessel 2111, the outflow valves 2251 to 2256 are closed, the auxiliary valve 2260 is opened, and the main valve 2118 is fully opened to temporarily raise the inside of the system. An operation of evacuating to a vacuum is performed as necessary.

In order to make the film formation uniform, it is also effective to rotate the support 2112 at a predetermined speed by a driving device (not shown) during the layer formation.

Further, it goes without saying that the above-mentioned gas types and valve operations are changed according to the conditions for forming each layer.

Next, a description will be given of a method of manufacturing a photosensitive member for an image forming apparatus by a high-frequency plasma CVD method (hereinafter referred to as “VHF-PCVD”) using a VHF band frequency as a power supply.

RF-PC in the manufacturing apparatus shown in FIG.
A deposition apparatus 2100 using the VD method is replaced with a deposition apparatus 3 shown in FIG.
By exchanging with 100 and connecting it to the raw material gas supply device 2200, it is possible to obtain a photoconductor manufacturing apparatus for an image forming apparatus having the following configuration by VHF-PCVD. The source gas supply device 2200 of the VHF-PCVD method
Is the same as that of FIG.
This will be described with reference to FIG.

This apparatus is roughly classified into a reaction vessel 3111 having a vacuum tight structure and capable of reducing pressure, a raw material gas supply apparatus 2
200 and an exhaust device (not shown) for reducing the pressure inside the reaction vessel 3111. Reaction vessel 31
In 11, a cylindrical support 3112, a heater 3113 for heating the support, a raw material gas introduction pipe 3114, and an electrode 3115 are provided, and a high frequency matching box 3120 is further connected to the electrode 3115. In addition, the reaction vessel 311
The inside of 1 is connected to a diffusion pump (not shown) through an exhaust pipe 3121.

The raw material gas supply device 2200 includes SiH ₄ ,
Cylinders 2221 to 2226 for source gases such as GeH ₄ , H ₂ , CH ₄ , B ₂ H ₆ , PH ₃ and valves 2231 to 2
236, inflow valve 2241 to 2246, outflow valve 2
251-2256 and mass flow controller 221
Each of the source gas cylinders is connected to a source gas introduction pipe 3114 in a reaction vessel 3111 via an auxiliary valve 2260. The space 3130 surrounded by the cylindrical support 3112 forms a discharge space.

The formation of a deposited film in this apparatus by the VHF-PCVD method can be performed as follows.

First, the cylindrical support 3112 is set in the reaction vessel 3111, the cylindrical support 3112 is rotated by the driving device 3120, and the inside of the reaction vessel 3111 is exhausted by an exhaust device (for example, a vacuum pump) not shown. 3121
And the pressure in the reaction vessel 3111 is reduced to 1 × 10
Adjust to ^-7 Torr or less. Subsequently, the temperature of the cylindrical support 3112 is set to 200 to 200 by the support heating heater 3113.
It is heated and maintained at a predetermined temperature of 350 ° C.

A source gas for forming a deposited film is supplied to a reaction vessel 311.
In order to make the gas flow into the valve 1, the gas cylinder valves 2231 to 2231
236, confirm that the leak valve (not shown) of the reaction vessel 3111 is closed,
2246, the outflow valves 2251 to 2256, and the auxiliary valve 2260 are confirmed to be open, and first, the main valve (not shown) is opened to exhaust the gas in the reaction vessel 3111 and the gas pipe (not shown).

Next, the reading of a vacuum gauge (not shown) was about 5 × 1.
When the pressure reaches 0 ^-6 Torr, the auxiliary valve 2260 and the outflow valves 2251 to 2256 are closed.

Thereafter, each gas was introduced from the gas cylinders 2221-2226 by opening the valves 2231-2236.
Each gas pressure is adjusted to 2 kg / by the pressure regulators 2261-2266.
Adjust to cm ² . Next, the inflow valves 2241 to 224
6 is gradually opened, and each gas is
It is introduced into 211-2216.

After the preparation for film formation is completed as described above, each layer is formed on the cylindrical support 3112 as follows.

When the temperature of the cylindrical support 3112 reaches a predetermined temperature, necessary ones of the outflow valves 2251 to 2256 and the auxiliary valve 2260 are gradually opened, and a predetermined gas is supplied from the gas cylinders 2221 to 2226 to the source gas introduction pipe 3114. Through the discharge space 31 in the reaction vessel 3111
30. Next, the mass flow controller 221
Each of the source gases is adjusted to have a predetermined flow rate according to 1-2216. At this time, the pressure in the discharge space 3130 becomes 1
The opening of the main valve (not shown) is adjusted while watching the vacuum gauge (not shown) so that the pressure becomes a predetermined pressure of Torr or less.

When the pressure becomes stable, the frequency becomes 500M.
Hz VHF power supply (not shown) is set to the desired power,
Discharge space 3130 through matching box 3120
VHF electric power is introduced to generate glow discharge. Thus, in the discharge space 3130 surrounded by the cylindrical support 3112, the introduced source gas is excited by the discharge energy and dissociated, and a predetermined deposited film is formed on the cylindrical support 3112. At this time, the cylindrical support 3
The support 112 is rotated at a desired rotation speed by a support rotating motor 3120 in order to achieve uniform layer formation.

After the formation of the desired film thickness, the supply of the VHF power is stopped, the outflow valves 2251 to 2256 are closed, the flow of gas into the reaction vessel 3111 is stopped, and the formation of the deposited film is completed.

By repeating the same operation a plurality of times, a desired photosensitive layer having a multilayer structure is formed.

When forming each layer, it goes without saying that all the outflow valves 2251 to 2256 other than the necessary gas are closed, and each gas is supplied to the inside of the reaction vessel 3111 and the outflow valve 2251. ~ 2256
Outflow valves 2251 to 2256, auxiliary valve 2260 is opened, and the main valve (not shown) is fully opened in order to avoid remaining in the piping from Perform the exhausting operation as needed.

It goes without saying that the above-mentioned gas species and valve operation can be changed according to the production conditions of each layer.

In any of the methods, the temperature of the support during the formation of the deposited film is in particular 200 to 350 ° C., preferably 23 to
0-330 degreeC, More preferably, 250-300 degreeC is preferable.

The heating method of the cylindrical support 3112 may be a heating element of a vacuum specification, and more specifically, an electric resistance heating element such as a sheet heater, a sheet heater, a ceramic heater, or the like. Examples of the heating element include a heat radiation lamp heating element such as a lamp and an infrared lamp, and a heating element using a liquid or a gas as a heating medium and a heat exchange unit. As the surface material of the heating means, metals such as stainless steel, nickel, aluminum, and copper, ceramics, and heat-resistant polymer resins can be used.

In addition to the above, a method other than providing a reaction vessel other than the reaction vessel, heating, and then transporting the support in the reaction vessel in a vacuum is used.

Further, particularly in the VHF-PCVD method,
The discharge space pressure is preferably 1 to 500 mTorr,
More preferably 3 to 300 mTorr, most preferably 5 to 300 mTorr
It is desirable to set to 100 mTorr.

In the VHF-PCVD method, the discharge space 3
The size and shape of the electrode 3115 provided on the electrode 130 may be any as long as they do not disturb the discharge. However, in practice, a cylindrical shape having a diameter of 1 to 100 mm is preferable. At this time,
The length of the electrode 3115 can be arbitrarily set as long as the electric field is uniformly applied to the cylindrical support 3112.

The material of the electrode 3115 may be any material as long as its surface becomes conductive. For example, stainless steel, Al, Cr, Mo, Au, In, Nb, Tb
metals such as e, V, Ti, Pt, Pb, and Fe; alloys thereof;
Plastics and the like are usually used.

Hereinafter, experimental examples and examples will be described in more detail by giving specific numerical values. Note that the present invention is not limited to these examples. <Experimental Example 1> Using an apparatus for manufacturing a photoreceptor for an image forming apparatus by the RF-PCVD method shown in FIG. A photoreceptor comprising an injection blocking layer, a photoconductive layer and a surface layer was prepared. Further, various photoconductors were produced by changing the mixing ratio of SiH ₄ and H ₂ and the discharge power of the photoconductive layer.

The prepared photoreceptor was set in an image forming apparatus (NP6060 manufactured by Canon Inc. modified for testing), and the reduction of images and carriers was evaluated.

[0205] Regarding the image, fog, streaks, and halftone density unevenness were comprehensively judged on the image.

On the other hand, a glass substrate (Corning Co., Ltd., 7059) and a Si wafer placed on a cylindrical sample holder were placed on an a-layer having a thickness of about 1 μm under the conditions for forming a photoconductive layer.
A Si film was deposited. An Al comb electrode was deposited on the deposited film on the glass substrate, and the characteristic energy (Eu) and the localized level density (DOS) of the exponential function were measured by CPM.
The hydrogen content of the deposited film on the wafer was measured by FTIR.

FIG. 4 shows the relationship between Eu and temperature characteristics at this time.
5 and 6 show the relationship between DOS, memory, and image flow. All samples had a hydrogen content between 10 and 30 atomic%.

As is clear from FIGS. 4, 5 and 6, Eu = 50-60 meV, DOS = 1 × 10 ¹⁴ -1
It was found that it was necessary to set the range of × 10 ¹⁶ cm ^-3 to obtain good electrophotographic properties. Similarly, a sample of the surface layer was prepared, and the resistance value was measured using a comb-shaped electrode.

Subsequently, a contact charging member was manufactured under the following conditions. The fur brush formed into a sheet having a width of 33 mm was configured as shown in FIG. The magnetic brush layer has a diameter of 20
μm, 4mm long fur brush density of about 150,000
A book / inch ² was used. The charging device composed of these was brought into contact with a member to be charged (photoreceptor) having a diameter of 108 to adjust the nip width to 31 to 33 mm. Note that the contact charging member was used stationary. The fur brush formed into a sheet having a width of 360 mm was configured as shown in FIG. The magnetic brush layer has a diameter of 2
0μm, 4mm long fur brush with a density of about 150,000
Those having 0 / inch ² were used. The charging device composed of these was brought into contact with a member to be charged (photoreceptor) having a diameter of 108 to adjust the nip width to 31 to 33 mm. Note that the contact charging member was used stationary.

The contact charging member and the auxiliary electrode thus produced were
The image forming apparatus shown in FIGS.
6060 was modified), and the charging ability was evaluated.
The voltage applied to the contact charging member was set at 600 Vdc.
The process speed was 300 mm / sec. 20 ° C,
A printing durability test of 100,000 sheets was performed in an environment of 40% RH.

The results are shown in FIG. 1x contact charging member
When having a resistance value of 10 ³ to 1 × 10 ¹¹ Ωcm, good charging characteristics were obtained. More preferably, when the contact charging member has a resistance value of 1 × 10 ⁴ to 1 × 10 ⁹ Ωcm, good charging characteristics and environmental characteristics such as image deletion were obtained.

When the resistance of the contact charging member was less than 1 × 10 ³ Ωcm, abnormal discharge and pinholes occurred, and the photosensitive member was damaged. The contact charging member has a resistance value of 1 × 10
^{When it was 12} Ωcm or more, the charging efficiency was reduced and charging due to injection hardly occurred. <Experiment 2> The image quality of the charging device according to the embodiment of the present invention was evaluated using the photoreceptor manufactured in Experiment 1. The following (1) to (5) were used as the contact charging member. (1) Contact charging member of the present invention used in Experimental Example 1: Contact charging member is stationary. (2) Contact charging member of the present invention used in Experimental Example 1: Contact charging member is stationary. (3) Diameter 20 μm, length 4mm, density about 150,000
A roller-type contact charging member in which a fur brush of book / inch ² is stretched around a conductive core shaft of φ18.

The contact charging member is stationary. (4) Diameter 20 μm, length 4 mm, density about 150,000
A roller-type contact charging member in which a fur brush of book / inch ² is stretched around a conductive core shaft of φ18.

The contact charging member rotates in the opposite direction to the photosensitive member at the same surface speed. (5) A contact charging member of a magnetic brush using a multipolar magnetic material of φ18.

(Number of magnetic poles: 12, magnetic field line density: 3000 Gauss): Contact charging members are stationary These contact charging members are formed by using an image forming apparatus (modified from Canon NP6060) as shown in FIGS. 10 (a) and 10 (b). Then, a durability test was performed on 100,000 sheets of A4 paper, and the image quality of the halftone image was evaluated. FIG. 15 shows the results.

By using the charging device of the present invention (the embodiment shown in FIGS. 1A and 1B), a high-quality image was obtained as in the case of using the magnetic brush in the initial image. Further, in the image after the durability test of 100,000 sheets of A4 paper, in the case of the roller type fur brush and the magnetic brush, the brush sweep unevenness occurred, but in the contact charging member of the present invention, A high-quality image almost the same as the initial image could be obtained. That is, when the contact charging member of the present invention was used, almost no reduction in image quality was observed.

As described above, by using the contact charging member of the present invention, the nip between the contact charging member and the member to be charged can be effectively widened in a limited space, and the movement of the contact charging member ( Even without rotation, the image quality was improved, and an image of stable image quality was obtained for a long time. FIG.
As shown in (e) and (f), the durability becomes more effective by combining the cleaning device with the contact charging member. <Experimental Example 3> Using the same image forming apparatus as in Experimental Example 1, the charging efficiency was evaluated by using the contact charging member (2) in Experimental Example 2 and changing the nip width from 8 to 33 mm. The voltage applied to the contact charging member was set at 700 Vdc. The process speed was 200 mm / sec, and the charging potential was measured immediately after charging. Similarly, the same evaluation was performed for the contact charging members of (3) and (4) of Experimental Example 2. FIG. 13 shows the results.

As shown in FIG. 13, in the charging device of the present invention, the charging efficiency is 90% in the nip width range of 8 to 33 mm.
This indicates that 98% especially when the nip width is 15 mm or more.
The above charging efficiency was shown.

In addition, as a result of performing the same experiment as in Experimental Example 2,
In the image after the durability test of 100,000 sheets of A4 paper, even if the nip width is 8 mm, the images of (1),
The same result as (2) was shown. That is, when using the contact charging member of the embodiment of the present invention, considering image defects such as sweeping unevenness, preferably a nip width of 10 mm or more,
More preferably, when the thickness is 15 mm or more, a very high charging efficiency can be obtained, the high charging efficiency is maintained even after the durability, and the configuration has a very excellent durability with no image defects. <Example 1> An aluminum cylinder having an outer diameter of 80 mm and a length of 358 mm was used as a substrate, and a 5% methanol solution of alkoxymethylated nylon was applied to the aluminum cylinder by a dipping method to form a film having a thickness of 1 mm.
An undercoat layer (intermediate layer) of μm was provided.

Next, titanyl phthalocyanine pigment was added to 10
Parts (parts by weight, hereinafter the same), 8 parts of polyvinyl butyral,
Then, 50 parts of cyclohexanone were mixed and dispersed for 20 hours by a sand mill using 100 parts of glass beads having a diameter of 1 mm. To this dispersion was added methyl ethyl kent 70-120.
(Appropriate) parts were added and applied on the undercoat layer.
After drying for 0.2 minute, a 0.2 μm charge generation layer was formed.

Next, 10 parts of a styryl compound having the structural formula shown in FIG. 16 and 10 parts of bisphenol Z-type polycarbonate were dissolved in 65 parts of monochlorobenzene on the charge generation layer. This solution was applied on a substrate by a dipping method, and dried with hot air at 120 ° C. for 60 minutes to form a charge transport layer having a thickness of 20 μm.

Next, a surface layer having a thickness of 1.0 μm was provided on the charge transport layer by the following method.

High melting point polyethylene terephthalate (A) obtained by using terephthalic acid as an acid component and ethylene glycol as a glycol component [intrinsic viscosity: 0.1.
70 dl / g, melting point 258 ° C. (10
The measurement was performed at a heating rate of ° C / min. The measurement sample was 5 mg, and the polyester resin to be measured was 280
Melted at 0 ° C. and quenched with ice water at 0 ° C.), glass point transition temperature 70 ° C.] 100 parts and epoxy resin (B) [epoxy equivalent 160; aromatic ester type; trade name: Epicoat 190P (oilification) Shell Epoxy Co., Ltd.)] was dissolved in 100 ml of a mixture of phenol and tetrachloroethane (1: 1). Further, 60 wt% of SnO ₂ powder was mixed into the above solution as charge retaining particles. Next, 3 parts of triphenylsulfonium hexafluoroantimonate (C) was added as a photopolymerization initiator to prepare a resin composition solution.

As for the light irradiation conditions, curing was performed by irradiating a 2 kW high-pressure mercury lamp (30 W / cm) at 130 ° C. for 8 seconds from a position 20 cm away.

In the image forming apparatus shown in FIGS. 10 (a) and 10 (b), the photosensitive drum manufactured in this manner is provided with auxiliary electrodes outside the image forming portion. , (2) were used. The carrier resistance was 8 × 10 ⁷ Ωcm.

Under these conditions, a 100,000-sheet printing test was conducted in an environment of 30 ° C. and 80% RH, and the reduction of images and carriers was evaluated. The voltage applied to the contact charging member was set at 700 Vdc. Process speed 200mm /
I went in sec. Charging potential measured immediately after charging is 680 V
That was all. When the same evaluation as in Experimental Example 2 was performed, a good image was obtained. Example 2 The following protective layer was formed in place of the protective layer used in Example 1. The same binder as that used in the charge transport layer was mixed with 60 wt% of SnO ₂ powder in an acrylic resin, and applied on the charge generation layer to a thickness of 1.0 μm to form a surface layer. A durability test was performed in the same manner as in Example 2, and the same evaluation as in Experimental Examples 2 (1) and (2) was performed. As a result, a good image was obtained when the contact charging member of the present invention was used. <Embodiment 3> Using an apparatus for manufacturing a photoreceptor for an image forming apparatus by the VHF-PCVD method shown in FIG. 3, a mirror-finished aluminum cylinder (support) having a diameter of 108 mm in the same manner as in Embodiment 1 was used. A photoreceptor comprising a charge injection blocking layer, a photoconductive layer, and a surface layer was prepared under the following conditions.

A durability test was performed on this photoreceptor in the same manner as in Example 2, and the same evaluation as in Experimental Examples 2 (1) and (2) was carried out. A good image was obtained when the contact charging member of the present invention was used. was gotten. Example 4 A photoconductor for an image forming apparatus was manufactured under the manufacturing conditions shown in FIG. 18 using the apparatus for manufacturing a photoconductor for an image forming apparatus shown in FIG.

A durability test was performed on this photosensitive member in the same manner as in Example 2, and the same evaluation as in Experimental Examples 2 (1) and (2) was carried out. As a result, a good image was obtained when the contact charging member of the present invention was used. was gotten.

[0229]

As described above, according to the present invention,
By forming the contact charging member with a belt-shaped conductive fur brush, more nips can be secured in a limited space, and high-quality images can be obtained without increasing the rotating speed of the conductive fur brush. Can now be obtained. Therefore, the life of the brush is prolonged due to wear, etc., and
It is possible to dramatically extend the life of the member to be charged,
Maintenance free is now possible.

Further, in the charging device of the present invention, the nip can be maximized in a limited space, which is excellent in space saving.

Further, since the conductive fur brush can be brought into contact with the surface of the member to be charged, high charging efficiency and high quality images can be obtained.

[Brief description of the drawings]

1A and 1B show a charging device of the present invention, wherein FIG. 1A is a perspective view showing a first embodiment, FIG. 1B is a perspective view showing a portion A in FIG.
FIG. 4D is an enlarged side view showing a portion C extracted from FIG.
(C) is an enlarged side view showing an extracted portion B of FIG. (B), (d) is a perspective view showing the second embodiment, and (e) is a perspective view showing the third embodiment. (F) is an enlarged side view extracting and showing part D of FIG. (E).

FIG. 2 is a schematic explanatory view of an example of an apparatus for forming a light receiving layer of a photoconductor for an image forming apparatus, which is an apparatus for manufacturing a photoconductor for an image forming apparatus by a glow discharge method using a high frequency in an RF band. is there.

FIG. 3 is an example of an apparatus for forming a photoreceptive layer of a photoreceptor for an image forming apparatus, and is a schematic explanatory view of an apparatus for manufacturing a photoreceptor for an image forming apparatus by a glow discharge method using VHF band high frequency. is there.

FIG. 4 is a diagram showing a relationship between characteristic energy (Eu) of an Urbach tail of a photoconductive layer and a temperature characteristic in a photoconductor for an image forming apparatus.

FIG. 5 is a diagram illustrating a relationship between a local density of state (DOS) of a photoconductive layer and an optical memory in a photoconductor for an image forming apparatus.

FIG. 6 is a diagram illustrating a relationship between a local density of state (DOS) of a photoconductive layer and an image deletion in a photoconductor for an image forming apparatus.

FIG. 7 shows a photoconductive layer of a photoconductor for an image forming apparatus.
FIG. 4 is a diagram showing a relationship between an absorption peak intensity ratio of a —H ₂ bond and a Si—H bond and halftone density unevenness (graininess).

FIG. 8 is a schematic configuration diagram illustrating an example of a conventional charging device.

FIG. 9 is a schematic configuration diagram showing another example of a conventional charging device.

FIG. 10 shows an embodiment of the image forming apparatus of the present invention,
1A is a schematic configuration diagram using the contact charging member of FIG. 1A, and FIG. 2B is a schematic configuration diagram using the contact charging member of FIG.

FIGS. 11A to 11E are partial cross-sectional views showing different configurations of a photoconductor for an image forming apparatus.

FIG. 12 is a characteristic diagram showing the resistance and charging state of the magnetic brush layer of the contact charging member according to the present invention.

FIG. 13 is a diagram illustrating a relationship between a nip width and a charging potential in the present invention and a conventional contact charging member.

FIG. 14 is a diagram showing conditions for manufacturing a photoconductor for an image forming apparatus of Experimental Example 1.

FIG. 15 is a diagram showing a result of a durability test of the contact charging member.

FIG. 16 is a diagram showing a structural formula of a styryl compound constituting a charge transport layer in Example 1.

FIG. 17 is a view showing conditions for manufacturing a photoconductor for an image forming apparatus of Example 3.

FIG. 18 is a diagram illustrating conditions for manufacturing a photoconductor for an image forming apparatus of Example 4.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 contact charging member 101 magnetic brush layer 102 flexible sheet (brush support) 103 conductive core shaft 104 conductive fur brush 105 charged member (photosensitive drum) 106 contact charging member 107 cleaning means (adsorption device) 1100 Charged body (photoconductor) 1101 Conductive support 1102 Photosensitive layer 1103 Photoconductive layer 1104 Surface layer 1106 Charge generation layer 1107 Charge transport layer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshiyuki Ehara 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (14)

[Claims] 1. A charging device in which a charging surface of a contact charging member to which a voltage is applied is charged by contacting the charging surface with a surface of a member to be charged, wherein the contact charging member is a belt-shaped conductive fur brush. A charging device, which is formed. 2. The charging device according to claim 1, wherein the conductive fur brush is formed by providing a magnetic brush layer on a belt-shaped flexible sheet. 3. The charging device according to claim 1, wherein the conductive fur brush is stretched so as to move around the charged body in an axial direction. 4. The charging device according to claim 1, wherein the conductive fur brush is stretched so as to move around a part of the member to be charged in a circumferential direction. 5. A charging device in which a charging surface of a contact charging member to which a voltage is applied is charged by bringing the charging surface into contact with the surface of a member to be charged, wherein the contact charging member is a belt-shaped conductive fur brush. The charging device, wherein the conductive fur brush is provided with cleaning means for removing dust. 6. The conductive fur brush according to claim 5, wherein a flexible sheet is stretched in a belt shape and a magnetic brush layer is provided on the flexible sheet. Charging device. 7. The charging device according to claim 5, wherein the conductive fur brush is stretched so as to move around in the axial direction of the member to be charged. 8. The charging device according to claim 5, wherein the conductive fur brush is stretched so as to move around a part of the member to be charged in a circumferential direction. 9. A charging device for contacting a contact charging member to which a voltage is applied so as to charge a member to be charged, an electrostatic latent image forming means for forming an electrostatic latent image on the member to be charged, An image forming apparatus comprising: a developing unit that visualizes an electrostatic latent image formed on a member to be charged and a transfer unit that transfers a toner image formed on the member to be charged to a recording medium by the developing unit. The image forming apparatus according to claim 1, wherein the charging device includes a contact charging member formed by a belt-shaped conductive fur brush. 10. The conductive fur brush according to claim 9, wherein a flexible sheet is stretched in a belt shape and a magnetic brush layer is provided on the flexible sheet. Image forming device. 11. The image forming apparatus according to claim 9, wherein the conductive fur brush is stretched so as to move around the charged member in an axial direction. 12. The image forming apparatus according to claim 9, wherein the conductive fur brush is stretched so as to move around a part of the member to be charged in a circumferential direction. 13. The method according to claim 1, wherein:
And a charged object charged by the charging device, wherein the charged object contains a conductive support, and at least one of a hydrogen atom and a halogen atom based on a silicon atom. A photoconductive layer having a non-single-crystal material and exhibiting photoconductivity, and a photoreceptive layer having a surface layer having a function of retaining charges,
Wherein the photoconductive layer contains 10 to 30 atomic% of hydrogen, and at least in a part where light is incident, a characteristic energy of an exponential function tail obtained from a sub-bandgap light absorption spectrum is 50 to 60 meV, And the density of localized states below the conduction band edge is 1 × 10 ¹⁴ cm ^-3 or more and 1 × 10 ¹⁶ cm
^The image forming apparatus is less than ^-3 . 14. The image forming apparatus according to claim 13, wherein the member to be charged is an electrophotographic photosensitive member having a conductive support, an organic photosensitive layer, and a surface layer containing charge holding particles. apparatus.