JP2003140445A - Charging member and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus for which contact electrostatic charge is used and which prevents the end chipping, image deletion, toner splashing, end leak, etc., of a photoreceptor. SOLUTION: This image forming apparatus has a process step of charging the photoreceptor by bringing a charging member into contact with the photoreceptor and applying a voltage thereto, a latent image forming process step of forming an electrostatic latent image on the photoreceptor by performing image exposure, a developing process of forming the electrostatic latent image to visualize by a toner and a process step of transferring a toner image onto a transfer material, in which the photoreceptor 1 is about amorphous silicon photoreceptor, the charging member 3 is formed by having an elastic layer 32 of the middle electric resistance into contact with the photoreceptor 1 on a conductive substrate 31 to be applied with at least the charging voltage, the middle resistance elastic layer 32 is in contact with a non-image forming region section (b) at the end in the longitudinal direction of the photoreceptor and the middle resistance elastic layer of the portion corresponding to the non-image forming region is formed on the conductive substrate 31 across an electrical insulating layer 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging member that charges an image carrier by bringing it into contact with an image carrier (a member to be charged) and applying a voltage thereto.

The present invention also relates to a process of contacting a photoconductor with a charging member to apply a voltage to charge the photoconductor, and a latent image forming an electrostatic latent image on the photoconductor by performing image exposure. The present invention relates to an image forming apparatus having an image forming step, a developing step of visualizing the electrostatic latent image with toner, and a step of transferring the toner image onto a transfer material.

[0003]

2. Description of the Related Art Conventionally, an electrophotographic copying machine, a laser beam printer, an electrostatic recording device, etc. are known as an image forming apparatus for charging a photosensitive member, which is a member to be charged, prior to image formation. It includes a step of uniformly charging the photoconductor or the dielectric as an image carrier to a predetermined potential. Conventionally, as the charging means, corona charging has been widely used in which a high voltage of 5 to 10 kV is applied to a charging wire of 60 μm to 100 μm to cause a corona discharge.

However, the above-mentioned corona charging has drawbacks that a large amount of ozone is generated, the cost of the power source is high because a high voltage is applied, and miniaturization is difficult.
As an alternative, a contact type charging device has been proposed. The contact type charging device presses the charging member against the surface of the member to be charged and applies a voltage (DC voltage or a superimposed voltage of DC voltage and AC voltage) to the charging member,
The surface of the body to be charged is charged to a predetermined polarity and potential. Such a contact type charging device has advantages such as a lower applied voltage and less ozone generation than the corona charging device.

For example, a roller-shaped contact type charging member often has a structure in which an elastic medium resistance layer is formed around a conductive core metal, and the resistance is adjusted in the medium resistance layer. There are a resistance control layer and a structure in which a surface layer is laminated. Examples of the material of the elastic medium resistance layer include urethane, SBR, EVA, SBS, SEBS, SIS,
There are resins and rubbers such as TPO, EPDM, EPM, NBR, IR, BR, silicone rubber, and epichlorohydrin rubber. Depending on the required resistance value, for example, carbon black, carbon fiber, metal oxides, metal powders, For example, a solid electrolyte such as chlorate or a conductivity-imparting agent such as a surfactant may be added.

What has to be an electrically medium resistance element is that when the resistance is low, when a defect such as a pinhole occurs in the photoconductor, the current concentrates on that part, and the object including the position is defective. If the charging voltage is not applied across the entire length of the charging member, a charging failure occurs, and if the resistance is high, the voltage of the applied charging voltage drops in the charging member, causing a charging failure.

However, in the case of charging the body to be charged by using the contact and proximity charging members, there are the following problems due to long-term durability.

In the contact type charging device utilizing the discharge in the minute gap, the charging member comes into contact with the surface of the charged member, so that the influence of the discharge near the contact surface of the charging member strongly acts on the charged member, The surface of the charged body deteriorates and is easily scraped, especially when an organic photoconductor is used as the charged body, the deterioration is remarkable, and the resin of the surface layer has a low molecular weight due to the influence of discharge, and the surface layer is easily scraped. . These effects are likely to occur at both ends of the charging member. This is because in the case of contact charging, the discharge occurs at a portion slightly apart from the contact portion with the organic photoconductor, so the discharge portion is the nip between the charging member and the photoconductor except for both ends of the charging member. Although it is only a small space that sandwiches, the discharge area in the peripheral direction of the drum when viewed from the circumferential direction of the drum due to the addition of discharge from the end of the charging member in addition to that Since it is wider than that of the other parts, the discharge time becomes longer than other parts, and the organic photoreceptor is deteriorated and scraped more frequently.

Therefore, the life of the photoconductor is shortened,
Image defects will occur due to uneven charging due to uneven scraping.

As a method for solving this, for example, in Japanese Patent Laid-Open No. 7-199599, the resistance value of the charging member at both ends is increased by applying an insulating coating or the like to a state in which the insulating layer is in direct contact with the member to be charged. However, in this case, due to the difference in film thickness due to the application of the insulating paint at the boundary between the place where the insulating paint is applied and the place where the insulating paint is not applied, On the other hand, a step is generated, and the electric discharge is concentrated in a minute space of the step, so that the photoconductor on the part is abraded more and the life of the photoconductor is shortened.
In addition, since the resistance of the edge portion becomes sharply higher than that of the image forming area, almost no potential is applied to the non-image forming area portion of the member to be charged, and especially in the case of the image forming method using reversal development, the potential difference is generated in that portion. Due to this, toner is developed in the non-image forming area, and there are problems such as contamination inside the machine due to scattering and toner continuing to develop, and fusion to the photoconductor, deterioration of the cleaner section, and increase in toner consumption. .

Further, Japanese Patent Laid-Open No. 7-261507 describes a charging member whose resistance gradually increases from the central portion to the end portion. In that case, uneven charging occurs due to the contamination state of the charging roller surface. However, there is a problem that an image such as density unevenness is likely to be generated.

In addition, a non-single crystalline deposition film containing silicon atoms represented by amorphous silicon as a main component, eg, containing hydrogen and / or halogen (eg, fluorine, chlorine, etc.) (eg, hydrogen or dangling bond is compensated. ) Amorphous deposited films such as amorphous silicon are
It has been proposed as a high-performance, highly durable, pollution-free photoconductor, and some of them have been put to practical use.

Japanese Unexamined Patent Publication No. 54-86341, USP
No. 4,265,991 discloses a technique for an electrophotographic photosensitive member in which a photoconductive layer is mainly formed of amorphous silicon. Further, JP-A-60-12554 discloses a surface layer containing carbon and halogen atoms on the surface of a photoconductive layer made of amorphous silicon containing silicon atoms, and further, JP-A-2-111962. Discloses a photoreceptor having a surface protective lubricating layer provided on the photosensitive layer.

Amorphous silicon type photoreceptors typified by amorphous silicon have a high sensitivity to long-wavelength light such as a semiconductor laser, and have the advantage that deterioration due to repeated use is hardly recognized. It is widely used as a photoconductor for electrophotography such as a copying machine and an LBP (laser beam printer).

As a method for forming a silicon-based non-single-crystal deposited film, a sputtering method, a method of decomposing a source gas by heat (thermal CVD method), a method of decomposing a source gas by light (optical CVD method), or a source by plasma Many methods such as a method of decomposing gas (plasma CVD method) are known. Among them, plasma CVD method, that is, the raw material gas is decomposed by direct current or high frequency, (RF, VHF), or glow discharge generated by using microwave, and the like, and glass, quartz, heat resistant synthetic resin film, stainless steel, aluminum, etc. The method of forming a deposited film on the desired substrate of
Not only the method for forming an amorphous silicon deposited film for electrophotography, but also the method for forming a deposited film for other purposes are currently in practical use, and various devices for that purpose have been proposed.

Also in the image forming apparatus using the above-mentioned amorphous silicon type photoconductor, the mainstream of the charging method is corona charging, and a large amount of ozone is generated with corona discharge. Due to the effect of corona products derived from ozone generated from this charger, the surface of the photoconductor becomes sensitive to humidity and it becomes easy to adsorb moisture, which causes the lateral flow of charges on the photoconductor surface, which is called image deletion. It has the drawback of causing degradation.

In order to prevent such image deletion, heating with a heater as described in Japanese Utility Model Publication No. 1-34205 and a magnet roller as described in Japanese Patent Publication No. 2-38956 are used. A method of removing corona products by rubbing the surface of an image bearing member, for example, a photosensitive member, which is a member to be charged, with a brush formed of magnetic toner.
A method of removing the corona product by rubbing the surface of the photoreceptor with an elastic roller as described in JP-A-1-100780 has been used.

The method of rubbing the surface of the photosensitive member is used for an amorphous silicon type photosensitive member having extremely high hardness.
This is one of the reasons why it is difficult to reduce the size of the cleaning device, such as the size of the cleaning device. Moreover, in order to prevent the adsorption of water on the surface of the photoconductor, the constant heating by the heater causes an increase in power consumption. The capacity of these heaters is usually around 15 to 80 W, which does not necessarily give the impression of a large amount of electricity, but in most cases they are always energized even at night, and the amount of electricity consumed per day is the same for the entire image forming apparatus. 5 to 15% of the power consumption of

Further, ozone, which is a cause of such image deletion, has conventionally been decomposed and rendered harmless by an ozone removal filter before being discharged. Thus, there is a demand for a method of significantly reducing the amount of ozone generated during charging.

For this purpose, a contact charging method is known in which the above-mentioned charging member is pressed against the photoconductor and the photoconductor is charged to a predetermined polarity and potential by applying a charging voltage to the charging member. A charging roller having a roller-shaped charging member is widely used.

Compared to the corona charging method, these contact charging methods can lower the applied voltage required to give a desired potential to the photosensitive member. The size of ozone generated during the charging process is extremely small, and the shield like corona charging is not required, so the structure of the exhaust system of the device can be simplified. The ozone product adheres to the surface of the image bearing member that is the surface to be charged, for example, the surface of the photosensitive member,
The surface of the photoconductor is sensitive to humidity due to the influence of corona products, and water is easily adsorbed, so that the flow of images due to the low resistance of the surface can be reduced as compared with the corona charging method.

As a method of charging the amorphous silicon type photoconductor by the contact charging method as described above, for example, in Japanese Patent Laid-Open No. 11-143176, the charging member and the surface roughness of the photoconductor are defined, and the charging uniformity is set. JP-A-6-83089 discloses a technique for charging an amorphous silicon photoconductor by contacting a metal blade, and JP-A-9-22168 and JP-A-8-1.
Japanese Patent No. 71262 describes a technique for reducing the generation of ozone by charging the photoconductor in the vicinity thereof.

However, even in the contact charging system,
Charging is performed by discharge in a minute gap between the photoconductor and the charging member, and when charging is performed by bringing the charging member into contact with an amorphous silicon-based photoconductor, an organic photoconductor (OPC)
In comparison with the above, since a large electrostatic capacity is required, a large amount of charging current is required to keep the same charging potential on the photoconductor, but depending on the process speed and the prescription of the photoconductor, it is about 2-3
Double the amount of current is required.

For this reason, the surface of the charging member that comes into contact with the photosensitive member is an organic resin or rubber, so that it is electrically or electrically deteriorated,
The longitudinal ends of the charging member, which are easily broken and are in contact with the photoconductor, are only minute spaces on both sides of the contact part (nip part) between the charging member and the photoconductor. In addition to that, discharge from the end of the charging member is also added, and when viewed from the peripheral direction of the photoconductor, the discharge area is wider in the peripheral direction of the photoconductor compared to places other than the end. Since it is longer than the portion of the charging member, a larger amount of charging current flows, which accelerates deterioration and destruction of the charging member, which gradually deteriorates from the end side to the center part, and the life of the charging member is shortened. The problem of shortening occurs.

Further, since the end portion has a large amount of discharge, the end portion has a large amount of abrasion, which shortens the life of the photosensitive member, causes uneven charging due to uneven abrasion, and causes image defects due to durability. Since there is little scraping of the body, there is a difference in the rubbing force between the center and end surfaces of the photoconductor due to the accumulation of discharge products, and an uneven load is applied to the cleaner part. When a mechanism is provided, chattering occurs and image defects such as cleaning defects occur.

Further, although the discharge products are less deposited than the corona charging, the discharge products are likely to be deposited due to the large discharge amount at the end portions as described above, causing image deletion and shortening the life. There was a problem.

Further, since the end portion has a large amount of discharge, a defect is likely to occur on the surface of the silicon drum, a leak occurs in which a current concentrates on the portion from the charging member, and a normal potential is applied to the image forming area portion. An image defect occurs because the user does not ride.

[0028] As a method for solving this, for example, Japanese Patent Laid-Open No. Hei 7
The charging members described in JP-A-199599 and JP-A-7-261507 can be cited, but these charging members also have the above-mentioned problems when a silicon-based drum is used.

[0029]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a charging member which solves the above problems.

That is, there is little scraping caused by the deterioration of the member to be charged due to the end discharge of the charging member without affecting the charging characteristics of the charging member in the image forming region, and the image is developed in the non-image forming region. An object of the present invention is to provide a charging member which prevents contamination in the machine due to toner scattering, drum fusion, and increase in toner consumption.

When an amorphous silicon type photosensitive member is used, deterioration of the charging member due to edge discharge of the charging member and uneven wear of the photosensitive member due to end discharge of the charging member without affecting the charging characteristics of the charging member in the image forming area due to durability, Prevents cleaning failures due to differences in the rubbing force on the surface of the photoconductor, and fouls inside the machine due to scattering by toner that develops in the non-image forming area.
An object of the present invention is to provide an image forming apparatus which prevents drum fusion.

[0032]

The present invention is a charging member and an image forming apparatus characterized by the following constitutions.

(1) A charging member that charges an image carrier by bringing it into contact with the image carrier and applying a voltage, and at least an electric resistance that contacts the image carrier on a conductive substrate to which a charging voltage is applied. Is a structure having an elastic layer with medium resistance, and the medium resistance elastic layer also contacts the non-image forming area portion at the end portion in the longitudinal direction of the image carrier, and the medium resistance elastic layer corresponding to the non-image forming area. Is formed on a conductive substrate via an electrically insulating layer, and a charging member.

(2) The charging member according to (1), characterized in that the length in the longitudinal direction of the medium resistance elastic layer corresponding to the non-image forming area is 3 mm or more.

(3) The film thickness of the electrically insulating layer in the portion corresponding to the non-image forming area is 1/10 or less of the film thickness of the medium resistance elastic layer, as described in (1) or (2). Charging member.

(4) The charging member according to any one of (1) to (3), wherein the film thickness of the electrically insulating layer in the portion corresponding to the non-image forming area is 5 μm to 500 μm.

(5) The hardness of the medium resistance elastic layer is JIS
35 at the hardness specified by the K6301 type A hardness tester
Characterized by being an elastic body having ˜75 degrees (1)
The charging member according to any one of (4) to (4).

(6) The electrically insulating layer in the portion corresponding to the non-image forming area is a layer formed by applying an insulative coating on a conductive substrate. (1) to (5) The charging member according to any one of claims.

(7) The electrically insulating layer in the portion corresponding to the non-image forming region is a layer formed by covering the conductive substrate with an insulating sheet or tape, and (1) to () The charging member according to any one of 5).

(8) A step of charging a photosensitive member by bringing a charging member into contact with the photosensitive member to apply a voltage, and a latent image formation in which an electrostatic latent image is formed on the photosensitive member by performing image exposure. In an image forming apparatus having a process, a developing process for visualizing the electrostatic latent image with toner, and a process for transferring the toner image to a transfer material, the photoconductor is an amorphous silicon photoconductor, and the charging member is at least charged. A conductive substrate to which a voltage is applied is provided with an elastic layer having a medium resistance in electrical resistance in contact with the photoconductor, and the non-image forming region at the end portion in the longitudinal direction of the photoconductor is also provided with the elastic layer. The image forming apparatus, wherein the resistance elastic layer is in contact with the medium resistance elastic layer corresponding to the non-image forming area, and is formed on the conductive substrate via an electrically insulating layer.

(9) The amorphous silicon type photoconductor has a photoconductive layer composed of a non-single-crystal material having silicon atoms as a matrix on a conductive substrate. The image forming apparatus described.

(10) The image forming apparatus according to (8) or (9), characterized in that the length in the longitudinal direction of the medium resistance elastic layer corresponding to the non-image forming area is 3 mm or more.

(11) Any one of (8) to (10), characterized in that the thickness of the electrically insulating layer in the portion corresponding to the non-image forming region is 1/10 or less of the thickness of the medium resistance elastic layer. An image forming apparatus according to claim 2.

(12) The image forming apparatus according to any one of (8) to (11), wherein the film thickness of the electrically insulating layer in the portion corresponding to the non-image forming area is 5 μm to 500 μm.

(13) The hardness of the medium resistance elastic layer is JIS
3 at the hardness specified by the K6301 type A hardness tester
The image forming apparatus according to any one of (8) to (12), which is an elastic body having an angle of 5 to 75 degrees.

(14) The electrically insulating layer in the portion corresponding to the non-image forming area is a layer formed by applying an insulating coating material on a conductive substrate. (8) to (13) The image forming apparatus according to any one of claims.

(15) The electrical insulating layer in the portion corresponding to the non-image forming area is a layer formed by covering the conductive substrate with an insulating sheet or a tape (8). The image forming apparatus according to any one of 13).

(16) The photosensitive body is an amorphous silicon type photosensitive body having a surface layer composed of a non-single crystalline hydrogenated carbon film. (8) to (15) Image forming apparatus.

(17) The amount of hydrogen in the non-single crystalline hydrogenated carbon film is 41% to 60% (16)
The image forming apparatus according to item 1.

(18) The photoconductor is a charge injection blocking layer,
The image forming apparatus according to any one of (8) to (17), which comprises three layers of a photoconductive layer and a surface layer.

(19) The photoconductor is a charge injection blocking layer,
The image forming apparatus according to any one of (8) to (17), which comprises four layers of a charge transport layer, a charge generation layer, and a surface layer.

[0052]

BEST MODE FOR CARRYING OUT THE INVENTION (1) Image Forming Apparatus FIG. 1 is a schematic structural model diagram of an example of an image forming apparatus. The image forming apparatus of this example is a digital copying machine using a laser beam (GP405, manufactured by Canon Inc.). The outline of the apparatus is equipped with a roller charger as a charging means for the photoreceptor,
A one-component developing device adopting a one-component jumping developing method is provided as a developing device, and a roller charger is provided as a transferring device.
An image forming apparatus (electrophotographic apparatus) of a reversal development type using a negative charging and negative toner, which is provided with a blade cleaning unit and a pre-charging exposure unit. Further, the photoconductor charger, the cleaning means, and the photoconductor are one-body type units.

Specifically, 1 is an electrophotographic photosensitive member as an image bearing member, and in this example, a photoconductive layer composed of a non-single crystal material having silicon atoms as a matrix is formed on a conductive substrate. It is a drum type amorphous silicon type photoconductor (hereinafter referred to as a photoconductor). The photoconductor 1 is rotationally driven in the clockwise direction indicated by the arrow at a predetermined peripheral speed.

Reference numeral 2 denotes an eraser lamp as pre-charging exposure means, which erases the electric memory of the photosensitive member 1.

Reference numeral 3 denotes a roller-shaped charging member (charging roller, roller charger) which is brought into contact with the photosensitive member 1. S1
Is a power source for applying a charging voltage to the charging member 3, and applies a predetermined charging voltage to the conductive substrate of the charging member 3.
As a result, the outer peripheral surface of the rotating photoconductor 1 is uniformly contact-charged to a predetermined negative potential in this example.

Reference numeral 4 is a laser beam scanner as an information writing means. Laser beam scanner 4
Outputs the laser light L modulated in accordance with the time-series electric digital pixel signal of the image information to scan and expose the uniformly charged surface of the photoconductor 1 described above. By this scanning exposure, the photoconductor 1
The potential of the light-exposed area on the uniformly charged surface is attenuated, and an electrostatic latent image corresponding to the scanning-exposure pattern is formed on the surface of the photoconductor due to the potential contrast with the potential of the dark area.

A toner developing device 5 is a developing means. In this example, the one-component developing device adopts the one-component jumping developing method of the reversal developing method with negative toner, and the toner adheres to the exposed bright portion of the photoconductor surface to reversal develop the electrostatic latent image as a toner image. To be done. 51 is a developing roller as a developer carrying member, and S2 is a developing voltage applying power source, which applies a predetermined developing voltage to the developing roller.

Reference numeral 6 denotes a paper feeding cassette. A recording material (transfer paper) P stacked and stored in the paper feeding cassette is separated and fed by a pickup roller 61, and passes through a sheet path 62 and a registration sensor 63. Then, the toner is fed to the transfer nip portion, which is the contact portion between the photoconductor 1 and the transfer roller 7 as the transfer means, at a predetermined control timing. A predetermined transfer voltage is applied to the transfer roller 7 from the transfer voltage applying power source S3, and the toner image formed on the surface of the photoconductor 1 is electrostatically transferred to the surface of the recording material P that is nipped and conveyed in the transfer nip portion. It

A drum cleaning device 8 removes contaminants such as transfer residual toner and paper dust remaining on the surface of the photoconductor 1 after the recording material is separated, and cleans the photoconductor surface.

A fixing device 9 introduces the recording material P separated from the surface of the photoconductor 1 through the transfer nip portion, and heats and fixes the unfixed toner image on the surface of the recording material P as a permanently fixed image. The recording material that has passed through the fixing device 9 is the sheet path 6
The sheet is discharged to the sheet discharge tray 10 through the sheet 4.

(2) Charging Member 3 FIG. 2 is a model view of the blade- or plate-shaped charging member 3. Reference numeral 31 is a conductive base, and 32 is a blade provided in electrical contact with the conductive base. It is a medium resistance member having a shape of elasticity. Blade-shaped elastic medium resistance member 3
Reference numeral 2 forms a charging nip portion N by contacting the surface of the photoconductor 1 with a predetermined pressing force. The conductive substrate 31 has a power source S1
From the above, a predetermined charging voltage is applied, and the surface of the photoconductor 1 is contact-charged with a predetermined polarity and potential.

FIG. 3 is a model view of a roller-shaped charging member (charging roller) 3, 31 is a core metal as a conductive base, 32 is an outer periphery of the core metal 31 and is electrically connected to the core metal 31 for conduction. This is a medium resistance layer having elasticity and provided in a roller shape. The elastic medium resistance layer 32 is brought into contact with the surface of the photoconductor 1 with a predetermined pressing force to form the charging nip portion N.
A predetermined charging voltage is applied from the power source S1 to the cored bar 31 which is a conductive substrate, and the surface of the photoconductor 1 is contact-charged with a predetermined polarity and potential.

2 and 3, a is the maximum image forming area width of the photoconductor 1 and b is a non-image forming area outside the maximum image forming area width a. The length of the charging member 3 is set longer than the maximum image forming area width.

As described above, in the charging member that contacts the member to be charged and charges the member to be charged, both ends of the charging member are added in addition to the upstream side and the downstream side of the nip when viewed from the circumferential direction of the member to be charged. The discharge from the part is also added, which accelerates the deterioration of the surface layer of the charged body and increases the abrasion of the charged body.Therefore, the resistance at the end of the charging member is increased and the amount of discharge to the charged body is reduced. It is necessary to suppress the deterioration of the charged body,
Further, in order to prevent the development of toner to the non-image forming area, the charging potential of the member to be charged is not sharply lowered from the image forming area to the end of the charging member, but is gradually reduced by the potential difference. It is possible to prevent the development of the toner, and it is possible to prevent contamination inside the machine due to scattering.

As the structure of the charging member therefor, in this embodiment, in the blade-shaped charging member 3 of FIG. 2 and the roller-shaped charging member 3 of FIG. Middle resistance layer 3 having elasticity directly on 31
2 is in contact, and the end portion of the medium resistance layer 32 is a charging member in contact with the photoconductor 1 via the insulating layer 33 formed on the conductive substrate 31.

When the middle resistance layer 32 is formed with the insulating layer 33 at the ends as described above, the resistance at both ends is increased, and the discharge amount at the ends can be reduced. Due to the conductivity of the resistance layer 32 in the longitudinal direction of the photoreceptor 1, the resistance between the conductive substrate 31 and the intermediate resistance layer 32 gradually increases toward the end portion, and as a result, it is a charged body as shown in FIG. The charging potential of the photoconductor 1 also gradually decreases toward the end, and the above-mentioned problems can be solved.

Further, in the non-image forming area b, at least the medium resistance layer 32 in contact with the photoconductor 1 must be present. If the intermediate resistance layer 32 does not exist, the edge scraping naturally increases, and the potential difference between the image forming area and the non-image forming area of the photoconductor 1 suddenly increases, causing the above-mentioned scattering and fusion. There will be problems.

Further, the length of the non-image forming area b is preferably 3 mm or more, and when it is smaller than 3 mm, the potential on the photosensitive member does not gradually decrease toward the end portion, but the potential decreases sharply at the end portion. As a result, the problems such as the above-mentioned scattering and fusion occur, the effect of reducing the discharge amount at the end is small, and the problem that the scraping of the end is large occurs. More preferably, the non-image forming area b is 10 mm or more.

Further, the medium resistance layer 32 must have elasticity. If it does not have elasticity, the middle resistance layer 32 of the non-image forming area b and the image forming area a is in contact with the photoreceptor at the boundary. However, due to the influence of the thickness of the insulating layer 33, a step is likely to occur, and the discharge is concentrated on that portion, which causes deterioration of the photoconductor 1. However, if it has elasticity, the film thickness of the insulating layer 33 is increased. Is absorbed, the contact state with the photosensitive member 1 becomes uniform, the concentration of discharge can be prevented, and the deterioration of the photosensitive member 1 can be suppressed.

Further, the insulating layer 33 in the portion corresponding to the non-image area
Is preferably less than 1/10 of the thickness of the medium resistance layer 32. When the film thickness of the insulating layer 33 is 1/10 or more, even if the intermediate resistance layer 32 has elasticity, the film thickness of the insulating layer cannot be absorbed and a step is generated in the contact state with the photoconductor 1, which is preferable. Absent. More preferably, it is less than 1/20.

Further, the thickness of the insulating layer 33 is 5 μm to 50 μm.
It is preferably 0 μm. If it is smaller than 5 μm,
Since the film thickness is thin, the insulating layer 33 is liable to cause dielectric breakdown depending on the charging voltage and the electrical insulating state cannot be maintained easily, which is not preferable. Is difficult to absorb and a step is likely to occur in the contact state with the photoconductor 1, which is not preferable. More preferably, it is 10 to 200 μm.

1) Medium Resistance Layer 32 As the material of the elastic body forming the medium resistance layer 32, for example, urethane, SBR, EVA, SBS, SEBS, SI
S, TPO, EPDM, EPM, NBR, IR, BR,
There are resins and rubbers such as silicone rubber and epichlorohydrin rubber. Depending on the required resistance value, for example, carbon black, carbon fiber, metal oxides, metal powder, solid electrolytes such as perchlorate, surfactants, etc. And the like, to which the conductivity-imparting agent is added.

Further, the medium resistance layer 32 may include a layer for controlling resistance and a surface layer having a function of preventing dirt on the outermost surface of the charging member 3. The material thereof is, for example, polyamide, Polyurethane, fluorine, polyvinyl alcohol, silicone, NBR, EPDM, CR, IR, B
There are resins such as R and hydrin rubber, rubbers, and the like, and for example, there are those obtained by mixing a conductive or insulating filler, an additive, or the like to obtain a desired resistance value.

In this case, even if the resistance control layer is included, there is no problem as long as the middle resistance layer has elasticity.

The hardness of the elastic medium resistance layer 32 is JIS
The hardness specified by the K6301 type A hardness tester is 35.
It is preferably about 70 degrees. If it is greater than 70 degrees, the hardness is too high, and it is difficult to absorb a step with the film thickness of the insulating layer, and it is difficult to make the contact state with the photoconductor 1 uniform.
If it is less than 5 degrees, the compression set is deteriorated, the charging member is deformed by leaving it for a long time, and the charge on the photoconductor 1 tends to become non-uniform, which is not preferable and the tackiness is increased. If the surface is easily contaminated and the transfer residual toner or the like adheres to the surface layer of the charging member and the roller surface is covered with the adhered matter, if the charging failure on the photoreceptor 1 or the adhered matter becomes large, Toner is scattered from the surface,
It is not preferable because it may contaminate the inside of the machine.

The resistance value of the intermediate resistance layer 32 is 1 × 10 ⁴ to 1 ×.
It is preferably 10 ¹⁰ Ω. If it is larger than 1 × 10 ¹⁰ Ω, the charging property to the photoconductor 1 is deteriorated and charging failure is caused, which is not preferable, and if it is smaller than 1 × 10 ⁴ Ω, when a pinhole exists in the photoconductor 1, it is present. The current is concentrated, the chargeability to other parts is deteriorated, and an excessive current flows in the pinhole portion, so that the intermediate resistance layer 32 is deteriorated due to dielectric breakdown, which is not preferable.

The above-mentioned resistance value measuring method is performed at a temperature of 22.5.
Under conditions of ℃ and 55% RH, a thin film having good conductivity such as aluminum foil is formed on the surface of the charging member 3 with a width of 1 cm and a length of 10 cm.
Cut it into pieces, press it against the surface of the charging member 2 (wrap it around in the case of a roller), connect the conductive base 31 and the thin film to both ends of the thin film megohm high tester (manufactured by HIOKI), and apply a DC voltage of 250 V to apply 10 V. Read the value in seconds.

For the above-mentioned resistance measurement, the volume resistivity value was measured according to JIS K6911.

The volume resistance value of the insulating layer 33 is 1 × 10 ¹⁰ Ω.
cm or more is preferable. 1 × 10 ¹⁰ Ω. If it is smaller than cm, the effect of the present invention is hard to be obtained because the discharge state at the end hardly changes, which is not preferable.

2) Conductive Substrate 31 As the conductive substrate 31, for example, metal such as aluminum, aluminum alloy, stainless steel and copper, or non-conductive surface such as glass, resin and paper, aluminum, palladium, rhodium, gold, Examples thereof include a conductive substrate in which a conductive thin film is formed by vapor-depositing or laminating a metal such as platinum, and a charging voltage is applied thereto.

A conductive pigment may be dispersed on the above metal or the like to form a resin having a resistance value of 10 ⁴ Ω or less or a conductive rubber having elasticity, which can be used as a conductive substrate. .

The resistance value of the conductive substrate 31 is preferably 1 × 10 ³ Ω or less, and if it is larger than 1 × 10 ³ Ω, the charging voltage is not favorably applied from the conductive substrate 31 to the intermediate resistance layer 32.
This is not preferable because it leads to poor charging of the photoreceptor 1.

3) Insulating Layer 33 As the insulating coating material for forming the insulating layer 33, for example, polyamide, polyurethane, fluorine, polyvinyl alcohol, silicone, NBR, EPDM, CR, I
Examples thereof include resins such as R, BR, and hydrin rubber, and rubbers, and an insulating filler, an additive, or the like may be mixed therein.

As a method of applying the coating material to the non-image forming area b of the conductive substrate 31, there is a method of applying masking such as a tape to the non-image forming area and applying the coating by dipping or spraying.

Examples of the insulating sheet and tape for forming the insulating layer 33 include urethane, PET, polyamide, fluororesin tape, sheet, and the like.
Examples thereof include a method of sticking them on the conductive substrate 31 or a method of coating the conductive substrate 31 with an adhesive or the like.

The insulating layer 33 is necessary from the region of the medium resistance layer 32 which is in contact with the photosensitive member 1 to the end, but if it does not interfere with the charging voltage applied to the conductive substrate 22, the insulating layer 33 extends beyond the end. It doesn't really matter.

The medium resistance layer 32 formed on the insulating layer 33 and the insulating layer 33 may be adhered to each other with an adhesive or the like.
The structure may be such that the intermediate resistance layer 32 is directly formed on the insulating layer 33 without any treatment.

(3) Organic Electrophotographic Photoreceptor As the electrophotographic photoreceptor to be charged, for example, an organic electrophotographic photoreceptor having a conductive support and a photosensitive layer formed on the support can be used. .

As the above-mentioned conductive support, the same conductive support as that used for an electrophotographic photosensitive member included in an ordinary image forming apparatus can be used. Specifically, iron,
Metals and alloys such as copper, nickel, aluminum, titanium, tin, antimony, indium, lead, zinc, gold and silver,
Alternatively, those oxides, carbons, conductive supports formed by molding conductive materials such as conductive resins, or coating or vapor-depositing the conductive materials on the surface of a base material having a desired shape and physical properties by an appropriate method. The conductive support obtained as described above can be used. Examples of the shape include a drum shape, a belt shape, and a sheet shape. In the present invention, a drum-shaped conductive support is preferably used.

The above-mentioned photosensitive layer is a layer containing both a charge generating material for generating photocarriers and a charge transporting material for transporting carriers at least on the side in contact with the conductive support (hereinafter referred to as charge generating layer and transporting layer). have. Instead of the charge generation and transport, a structure in which a charge generation layer containing a charge generation material that generates photocarriers and a charge transport layer containing a charge transport material that transports carriers are stacked may be used. In that case, either the charge generation layer or the charge transport layer may be formed on the side in contact with the conductive support.

Further, a conductive layer and an undercoat layer may be provided between the charge generation layer, the transport layer and the conductive support in this order from the conductive support side. Further, the conductive layer and the undercoat layer can be combined into one layer. In this specification, the photosensitive layer is used as a general concept of all layers formed on the conductive support.

Specific examples of the charge generating material include phthalocyanine pigments, azo pigments, amorphous silicon, triphenylmethane dyes and the like.

Specific examples of the charge transport material include pyrene compounds, carbazole compounds, hydrazone compounds, triphenylamine compounds, styryl compounds, stilbene compounds and the like.

Specific examples of the binder resin include polyester, polyurethane, polyarylate, polyethylene, polystyrene, polybutadiene, polycarbonate, phenol resin, epoxy resin and butyral resin. In addition, reactive epoxy, (meth)
Acrylic monomers and oligomers can also be used after mixing them.

The charge generation / transport layer may be replaced with a two-layer structure of a charge generation layer and a charge transport layer. The charge generation layer may be composed of only the charge generation material, but in other cases, it may contain the binder resin or the like.

The content of the charge generating material in the charge generating layer is preferably 30 to 100% by mass based on the total amount of the layer constituting material. Further, the thickness of the charge generation layer is preferably about 0.1 to 0.5 μm.

The charge transport layer comprises a binder resin and
With respect to the binder resin, preferably 30 to 120
The charge transport material may be contained in an amount of% by mass, and if necessary, various optional components similar to those contained in a usual charge transport layer may be contained. The thickness of the charge transport layer is 10-3
It is preferably about 0 μm.

The optional undercoat layer is a layer provided for preventing, for example, charges injected from the conductive support from affecting charges charged on the surface of the photosensitive layer. It can be composed of the same binder resin and may contain the above-mentioned conductive material or acceptor. The thickness of the undercoat layer is preferably about 0.1 to 1.0 μm.

Further, the conductive layer is, for example, a layer provided to improve the surface condition of the conductive support,
It is possible to adopt a structure in which the conductive material is dispersed in the same binder resin as described above. The thickness of the conductive layer is 10-2
It is preferably about 0 μm.

The method for producing the electrophotographic photosensitive member used in the present invention is usually a conductive support, a conductive layer, and
A method of laminating an undercoat layer, a charge generation layer, a transport layer and a charge injection layer by vapor deposition, coating, etc. is used. Regarding the lamination method, specifically, a bar coater, a knife coater, a roll coater, an attritor, a spray, a dip coating, an electrostatic coating, a powder coating or the like is used for coating. The above-mentioned coating method can be carried out by applying a solution or dispersion in which the constituents of each layer are dissolved or dispersed in an organic solvent or the like and then removing the solvent by drying or the like. Alternatively, when a reaction-curable binder resin is used, each layer constituent component is dissolved or dispersed in a resin raw material component and an appropriate organic solvent or the like added as necessary, and a solution or dispersion is prepared by the method described above. After the application, the resin raw material is reacted and cured by, for example, heat or light, and the solvent may be removed by drying or the like, if necessary.

(4) Amorphous silicon (a-Si)
System Photoreceptor FIG. 5A and FIG. 5B are examples of schematic cross-sectional views of a light receiving member of an amorphous silicon photoconductor,
(A) is a single-layer type light receiving member in which the photoconductive layer is a single layer in which the functions are not separated. Further, (B) is a function-separated type light-receiving member in which the photoconductive layer is separated into a charge generation layer and a charge transport layer.

The amorphous silicon type photoreceptor shown in (A) is a conductive substrate 101 made of aluminum or the like, and a charge injection blocking layer 102 sequentially laminated on the surface of the conductive substrate 101.
And a photoconductive layer 103 and a surface layer 104. here,
The charge injection blocking layer 102 blocks injection of charges from the conductive substrate 101 into the photoconductive layer 103, and is provided as necessary. The photoconductive layer 103 is made of an amorphous material containing at least silicon atoms and exhibits photoconductivity. Further, the surface layer 104 is made of an aC: H film containing carbon atoms and hydrogen atoms, and has the ability to retain a visible image in an electrophotographic apparatus.

In the amorphous silicon type photosensitive member shown in (B), the photoconductive layer 103 has a charge transport layer 106 made of an amorphous material containing at least silicon atoms and carbon atoms.
And a charge generation layer 105 composed of an amorphous material containing at least silicon atoms, which are sequentially stacked, and are a function-separated type light receiving member. Carriers mainly generated in the charge generation layer 105 that irradiate the light receiving member with light pass through the charge transport layer 106 and reach the conductive substrate 101.

As the film forming gas for the surface layer 104,
Gases such as CH ₄ , C ₂ H ₆ , C ₃ H ₈ and C ₄ H ₁₀ and hydrocarbons that can be gasified are mentioned as being effectively used. In addition, these raw material gases for supplying carbon may be diluted with a gas such as H ₂ , He, Ar, or Ne, if necessary.

The above-mentioned photoreceptor may not have a surface layer, but preferably has a surface layer of non-single crystalline hydrogenated carbon film, more preferably non-single crystalline hydrogen. The photoconductor has a surface layer in which the hydrogen content of the carbon dioxide film is 41 to 60%.

By having the above-mentioned surface layer, the surface layer of the photoconductor becomes harder, and the effect of suppressing scraping is achieved, and since there is no hydrophilic group in the surface layer, the discharge products are less likely to adhere to the surface layer and the image flow is reduced. Is suppressed, and it is particularly preferable that the amount of hydrogen in the non-single crystalline hydrogenated carbon film is in the range of 41 to 60% because the effect is further exhibited. If the hydrogen content is less than 41%, the abrasion tends to increase, so that the life of the photoconductor is shortened, and if it exceeds 60%, image deletion due to the accumulation of discharge products tends to occur, which is not preferable.

FIG. 6 is a diagram schematically showing an example of a general apparatus for depositing a light receiving member by the plasma CVD method.

This apparatus is roughly classified into a deposition apparatus 210.
0, a source gas supply device 2200, and an exhaust device (not shown) for reducing the pressure inside the reaction vessel 2110. A cylindrical film-forming substrate 2112, a heater 2113 for heating the cylindrical film-forming substrate, and a source gas introducing pipe 21 which are connected to earth in a reaction vessel 2110 in the deposition apparatus 2100.
14 is installed, and a high frequency matching box 21 is further installed.
A high frequency power supply 2120 is connected via 15.

The source gas supply device 2200 is made of SiH ₄ ,
Source gas cylinders 2221 to 2226 such as H ₂ , CH ₄ , NO, B ₂ H ₆ , and CH ₄ and valves 2231 to 2236, 22
41 to 2246, 2251 to 2256 and mass flow controllers 2211 to 2216, and a cylinder of each constituent gas is a reaction vessel 211 via a valve 2260.
0 is connected to the gas introduction pipe 2114.

The cylindrical film-forming substrate 2112 is installed on the conductive pedestal 2123 to be grounded.

An example of the procedure of the method for forming the light receiving member using the apparatus shown in FIG. 6 will be described below.

The cylindrical film-forming substrate 2 is placed in the reaction vessel 2110.
112 is installed and the inside of the reaction vessel 2110 is exhausted by an exhaust device (not shown) (for example, a vacuum pump). Subsequently, the temperature of the cylindrical film-forming substrate 2112 is controlled to a desired temperature of 20 ° C. to 500 ° C. by the cylindrical film-forming substrate heating heater 2113. Next, in order to allow the raw material gas for forming the light receiving member to flow into the reaction vessel 2110, gas cylinder valves 2231 to 2236 and a reaction vessel leak valve 2117.
Check that the inlet valve 224 is closed.
1 to 2246, the outflow valves 2251 to 2256, and the auxiliary valve 2260 are confirmed to be opened, the main valve 2118 is opened, and the reaction container 2110 and the gas supply pipe 2116 are exhausted.

Thereafter, the reading of the vacuum system 2119 is 5 × 10.
At the time of ^-6 Torr, the auxiliary valve 2260 and the outflow valves 2251 to 2256 are closed. Then gas cylinder 2
Valves 2231 to 223 from 221 to 2226
6 is opened and introduced, and each gas pressure is adjusted to ² kg / cm ² by the pressure adjusters 2261 to 2266. Next, the inflow valves 2241 to 2246 are gradually opened to introduce the respective gases into the mass flow controllers 2211 to 2216.

After the film formation preparation is completed by the above procedure, the photoconductive layer is first formed on the cylindrical film formation base 2112.

That is, when the cylindrical film-forming substrate 2112 reaches a desired temperature, each outflow valve 2251-2
Necessary ones of 256 and the auxiliary valve 2260 are gradually opened, and a desired raw material gas is supplied from each of the gas cylinders 2221 to 2226 via the gas introduction pipe 2114 to the reaction vessel 211.
Install within 0. Next, each mass flow controller 2
211 to 2216 are adjusted so that each source gas has a desired flow rate. At that time, the inside of the reaction vessel 2110 is 1
The vacuum gauge 211 should be adjusted to the desired pressure below Torr.
While watching 9, the opening of the main valve 2118 is adjusted.
When the internal pressure is stable, the high frequency power supply 2120 is set to a desired power and, for example, the frequency is 1 MHz to 450 MHz.
The high frequency electric power of is supplied to the cathode electrode 2111 through the high frequency matching box 2115 to cause high frequency glow discharge. This discharge energy causes the reaction container 21
The source gases introduced into the chamber 10 are decomposed, and a photoconductive layer containing desired silicon atoms as a main component is deposited on the cylindrical film-forming substrate 2112. After the desired film thickness is formed, the supply of high frequency power is stopped and each outflow valve 2251-
2256 is closed to stop the flow of each source gas into the reaction vessel 2110, and the formation of the photoconductive layer is completed.

Known compositions and film thicknesses of the photoconductive layer can be used.

When the surface layer is formed on the photoconductive layer, the above operation may be basically repeated.

FIG. 7 shows a plasma CV using a high frequency power source.
It is the figure which showed typically another example of the deposition apparatus of the light receiving member by D method.

This apparatus is roughly classified into a deposited layer 3100,
It comprises a source gas supply device 3200 and an exhaust device (not shown) for reducing the pressure inside the reaction container 3110. In the reaction vessel 3110 in the deposition apparatus 3100, a cylindrical film-forming target substrate 3112 connected to the ground, a heater 3113 for heating the cylindrical film-forming target substrate, and a source gas introducing pipe 31.
14 is installed and a high frequency matching box 31 is further installed.
A high frequency power supply 3120 is connected via 15.

The source gas supply device 3200 is composed of SiH ₄ ,
Source gas cylinders 3221 to 326, such as H ₂ , CH ₄ , NO, B ₂ H ₆ , and CH ₄ and valves 3231 to 236, 32
41-3246, 3251-3256, and mass flow controllers 3211-3216, and the cylinder of each constituent gas is a reaction container 311 via a valve 3260.
0 is connected to the gas introduction pipe 3114.

The cylindrical film-forming substrate 3112 is installed on the conductive pedestal 3123 to be grounded. The cathode electrode 3111 is made of a conductive material and is insulated by the insulating material 3121.

The conductive material used for the conductive pedestal 3123 is copper, aluminum, gold, platinum, lead, nickel, cobalt, iron, chromium, molybdenum, titanium, stainless steel, or a composite of two or more of these materials. Materials can be used.

As an insulating material for insulating the cathode electrode 3111, an insulating material such as ceramics, Teflon (registered trademark), mica, glass, quartz, silicone rubber, polyethylene or polypropylene can be used.

As the matching box 3115 used, any structure can be preferably used as long as it can match the load with the high frequency power supply 3120.
Further, as a method for obtaining matching, a method of automatically adjusting is preferable, but a method of manually adjusting does not affect the effect of the present invention at all.

Cathode electrode 31 to which high frequency power is applied
The material of 11 is copper, aluminum, gold, silver, platinum,
Lead, nickel, cobalt, iron, chromium, molybdenum, titanium, stainless steel, and a composite material of two or more kinds of these materials can be used. The shape is preferably a cylindrical shape, but an elliptical shape or a polygonal shape may be used if necessary.

The cathode electrode 3111 may be provided with a cooling means if necessary. As a specific cooling means, cooling with water, air, liquid nitrogen, a Peltier element or the like is used as needed.

Cylindrical film forming substrate 3112 used in the present invention
May have any material or shape according to the purpose of use. For example, regarding the shape, when an electrophotographic photosensitive member is manufactured, a cylindrical shape is desirable, but a flat plate shape or another shape may be used as necessary. As for the material, copper, aluminum, gold, silver, platinum, lead, nickel, cobalt, iron, chromium, molybdenum, titanium, stainless steel, and a composite material of two or more kinds of these materials, and further polyester, polyethylene, polycarbonate. ,
An insulating material such as cellulose acetero, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, glass, quartz, ceramics or paper coated with a conductive material can be used.

An example of the procedure of the method for forming the light receiving member using the apparatus shown in FIG. 7 will be described below.

The cylindrical film-forming substrate 3 is placed in the reaction vessel 3110.
112 is installed and the inside of the reaction container 3110 is exhausted by an exhaust device (not shown) (for example, a vacuum pump). Then, the temperature of the cylindrical film-forming substrate 3112 is controlled to a desired temperature of 20 ° C. to 500 ° C. by the cylindrical film-forming substrate heating heater 3113.

A raw material gas for forming the light receiving member is supplied to the reaction vessel 3
In order to make it flow into 110, valve 3231 of gas cylinder
~ 3236, make sure that the leak valve 2117 of the reaction vessel is closed, and inflow valves 3241 to 32
46, outflow valves 3251 to 256, auxiliary valve 32
Check that 60 is open, and then open the main valve 311.
8 is opened and the reaction container 3110 and the gas supply pipe 3116 are opened.
Exhaust.

Next, the reading of the vacuum system 3119 is 5 × 10 ^-6 T
When it becomes orrr, the auxiliary valve 3260 and the outflow valves 3251 to 256 are closed. Then gas cylinder 322
Each gas is introduced from 1 to 3226 by opening the valves 3231 to 236, and each gas pressure is adjusted to ² kg / cm ² by the pressure adjusters 3261 to 3266. Next, the inflow valve 32
41 to 246 are gradually opened to introduce each gas into the mass flow controllers 3211 to 3216.

After the film-forming preparation is completed by the above procedure, the photoconductive layer is formed on the cylindrical film-forming substrate 3112.

When the cylindrical film-forming substrate 3112 reaches a desired temperature, the necessary one of the outflow valves 3251 to 256 and the auxiliary valve 3260 are gradually opened.
The gas is introduced into the reaction vessel 3110 from each of the gas cylinders 3221 to 3226 through a desired raw material gas introduction pipe 3114.
Next, each mass flow controller 3211 to 3216
Is adjusted so that each source gas has a predetermined flow rate. At that time, the opening of the main valve 3118 is adjusted while observing the vacuum gauge 3119 so that the inside of the reaction container 3110 has a predetermined pressure of 1 Torr or less. When the internal pressure is stable, the high frequency power supply 3120 is set to a desired power and, for example, high frequency power having a frequency of 1 MHz to 450 MHz is supplied to the cathode electrode 3111 through the high frequency matching box 3115 to cause high frequency glow discharge. The source energy introduced into the reaction vessel 3110 is decomposed by this discharge energy, and a deposited film containing silicon atoms as a main component is formed on the cylindrical film-forming substrate 3112. After the desired film thickness is formed, the supply of the high frequency power is stopped, the outflow valves 3251 to 2566 are closed to stop the inflow of each source gas into the reaction vessel 3110, and the formation of the deposited film is completed.

Also, when the surface layer of the present invention is formed, the above operation may be basically repeated.

Specifically, each outflow valve 3251 to 32
Necessary ones of 56 and the auxiliary valve 3260 are gradually opened, and the raw material gas required for the surface layer is introduced into the reaction vessel 2110 from each of the gas cylinders 3221 to 226 via the gas introduction pipe 2114. Next, the mass flow controllers 3211 to 3216 adjust the raw material gases so that they have a predetermined flow rate. At that time, the reaction vessel 3110
The opening of the main valve 3118 is adjusted while observing the vacuum gauge 3119 so that the inside has a predetermined pressure of 1 Torr or less. When the internal pressure is stable, the high frequency power supply 3120 is set to a desired power and high frequency power having a frequency of 1 MHz to 450 MHz is supplied to the cathode electrode 3111 through the high frequency matching box 3115 to cause high frequency glow discharge. By this discharge energy, the reaction container 311
Each raw material gas introduced into 0 is decomposed to form a surface layer. After the desired film thickness is formed, the supply of the high frequency power is stopped, the outflow valves 3251 to 2566 are closed to stop the inflow of each source gas into the reaction vessel 3110, and the formation of the surface layer is completed.

While the film is being formed, the cylindrical film-forming substrate 3112 may be rotated at a predetermined speed by a driving device (not shown).

(5) Examples Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. First, an example in which an amorphous silicon type photosensitive member is used will be described.

1) Photoreceptor Production Example 1 Using the plasma CVD apparatus shown in FIG. 6, a lower blocking layer, a photoconductive layer, and a surface layer were sequentially laminated on a cylindrical Al substrate under the following conditions, and negative charging was performed. The light receiving member used was completed.

Lower blocking layer: SiH ₄ 100 ml / min (normal) H ₂ 300 ml / min (normal) PH ₃ 800 ppm (relative to SiH ₄ ) NO 5 ml / min (normal) Power 150 W Internal pressure 80 Pa Substrate temperature 280 ° C. Membrane Thickness 3 μm Photoconductive layer SiH ₄ 350 ml / min (normal) H ₂ 600 ml / min (normal) B ₂ H ₆ 0.5 ppm (relative to SiH ₄ ) Power 400 W Internal pressure 73 Pa Base temperature 280 ° C. Thickness 20 μm SiC Surface layer: SiH ₄ 20 ml / min (normal) CH ₄ 500 ml / min (normal) Power 150 W Internal pressure 67 Pa Substrate temperature 250 ° C. Film thickness 0.5 μm 2) Photoreceptor Production Examples 2, 3 and 4 ． No. 1 and a new surface layer of 0.2 μm was further deposited on the surface layer under the conditions shown in Table 1 below. 2-4 were obtained.

[0140]

[Table 1]

The above photoconductor No. In Nos. 2 to 4, in order to measure the hydrogen content, a surface layer sample was prepared on a silicon wafer under the conditions shown in Table 1 above, and the hydrogen content H /
The results of the measurement of (C + H) are shown in Table 2 below.

[0142]

[Table 2]

3) Manufacturing Example 1 of charging member ． Preparation of conductive substrate A stainless steel core having a resistance of 2Ω was prepared.

.. Adjustment of Insulating Paint on Both Ends As an insulating paint for painting both ends, 100 parts by weight of silicone resin and 300 parts by weight of toluene were mixed to adjust the silicone paint, and the volume resistivity was measured according to JIS K6911. It was 10 ¹² Ωcm.

.. Adjustment of rubber compound of medium resistance layer 100 parts by weight of epichlorohydrin rubber terpolymer (epichlorohydrin: ethylene oxide: allyl glycidyl ether = 40 mol%: 56 mol%: 4 mol%) light calcium carbonate 30 parts by weight plasticizer (molecular weight 8000) 10 parts by weight Parts Stearic acid 1 part by weight Anti-aging agent MB 1.5 parts by weight Zinc oxide 10 parts by weight Quaternary ammonium salt 1 part by weight
Kneading for minutes to adjust the raw material compound, and to this compound, 2 parts by weight of sulfur as a vulcanizing agent, 1 part by weight of DM as a vulcanization accelerator, and 0.5 parts by weight of TS are added to 100 parts by weight of epichlorohydrin rubber as a raw material rubber. And add 20
The mixture was kneaded for 10 minutes with a two-roll machine cooled to 0 ° C. to prepare a rubber compound.

.. Preparation of Charging Member The insulating paint prepared above was applied to the image forming area a at both ends of the φ8 stainless steel cored bar corresponding to the non-image forming area b.
Was masked and applied by dipping so as to have a thickness of 20 μm, and after removing the masking, it was dried at 130 ° C. for 80 minutes to form an insulating layer.

Using the above core metal and the above rubber compound, a roller was formed by an extrusion molding machine so as to have a roller shape with an outer diameter of φ16, and was heated and vulcanized at 150 ° C. for 2 hours, and the charging roller No. Got 1.

4) Manufacturing Example 2 of Charging Member Preparation of paint for surface layer 100 parts by weight of fluoroacryl resin and 250 parts by weight of toluene are mixed to dissolve the resin, and 60 parts of electroconductive titanium oxide is dispersed therein for 2 hours by a paint shaker to prepare a paint of electroconductive fluoroacryl resin. did.

.. Preparation of charging member Charging roll No. 1 was coated with the above surface layer by dipping so as to have a thickness of 20 μm, and then at 120 ° C.
Charging roller No. 1 similar to charging roller 1 except that it was dried for 5 hours. Got 2.

5) Charging Member Production Example 3 The charging roller No. 3 was manufactured except that a polyimide tape having a thickness of 100 μm and a volume resistance value of 1 × 10 ¹³ Ωcm was wound around the non-image forming area of the core metal about once. Similar to No. 2 charging roller No. Got 3.

6) Charging Member Manufacturing Example 4 The rubber compound prepared in Charging Member Manufacturing Example 1 was used as φ7.
It was placed in a bamboo ring-shaped mold having an outer diameter of φ17 (thickness 4.25) in the hole of No. 5, and was heated and vulcanized at 150 ° C. for 2 hours to prepare a bamboo ring-shaped rubber roll. Further, a PET tape with a thickness of 50 μm was wrapped around the non-image forming area of the φ8 stainless steel core metal for about one lap, and this was inserted into the bamboo ring-shaped rubber roller produced as described above while sending air, and after insertion, Diameter is φ1
Charging roller N that has been subjected to a wide polishing process so as to be No. 6
o. Got 4.

7) Charging Member Production Example 5 A charging roller similar to the charging roller 4 except that a core metal wound around the core with the PET tape of 50 μm thickness used in the above-mentioned charging member Production Example 4 for about 9 turns was used. No. Got 5.

8) Charging Member Manufacturing Example 6 Charging roller N except that the length of the non-image forming area is different.
o. Similar to No. 2 charging roller No. Got 6.

9) Charging Member Manufacturing Example 7 Charging roller N except that the length of the non-image forming area is different.
o. Similar to No. 2 charging roller No. Got 7.

10) Charging Member Production Example 8 Charging roller No. 10 except that the rubber compound contained 0.1 part of the plasticizer and 10 parts of the vulcanizing agent sulfur. Similar to the charging roller No. 1 Got 8.

11) Charging Member Production Example 9 Charging roller No. 1 except that the rubber compound contained 25 parts of plasticizer and 1 part of vulcanizing agent of sulfur. Similar to the charging roller No. 1 Got 9.

12) Charging Member Production Example 10 Charging roller No. 10 was used except that the insulating paint prepared in Charging Member Production Example 1 was applied to the cored bar portion of the non-image forming area in a thickness of 3.8 μm. As with No. 2, the charging roller No. Got 10.

13) Charging Member Manufacturing Example 11 Charging roller No. 11 was used except that the PET tape having a thickness of 50 μm used in Charging Member Manufacturing Example 4 was wound around the cored bar portion of the non-image forming area for about 13 times. Charging roller No. 3 similar to
I got 11.

14) Charging Member Manufacturing Example 12 Charging roller N except that the length of the non-image forming area is different.
o. Similar to No. 2 charging roller No. I got 12.

15) Charging Member Production Example 13 Charging roller No. 15 was manufactured except that the core bar was not coated with the insulating paint. A charging roller X (Comparative Example) similar to that of No. 2 was obtained.

16) Manufacturing Example of Charging Member 14 The medium resistance layer of the non-image forming area of the charging roller 2 was removed by a cutter to obtain a charging roller Y (comparative example) which charges only the image area.

17) Charging Member Manufacturing Example 15 The insulating coating material prepared in Charging Member Manufacturing Example 1 was applied on the medium resistance layer of the charging roller X corresponding to the non-image forming area in a thickness of 30 μm, and at 130 ° C. A charging roller W (comparative example) dried for 40 minutes was obtained.

18) Charging Member Production Example 16 A conductive base having a conductive rubber layer having the following composition and having a film thickness of 2 mm formed on a core metal made of Φ6 stainless steel was used, and a non-image forming area was formed on the conductive base. Charging member manufacturing example 2 except that the silicone resin paint shown in charging member manufacturing example 1 was applied so as to have a thickness of 20 μm, and the outer diameter of the roller was molded to Φ14.
Similar to Φ14 charging member No. I got 13.

Silicone rubber 100 parts by weight Zinc oxide 5 parts by weight Higher fatty acid 1 part by weight Conductive carbon black 13 parts by weight Paraffin oil 10 parts by weight Sulfur 2 parts by weight Vulcanization accelerator MBT 1 part by weight Vulcanization accelerator TMTD 1.5 1.5 parts by weight of vulcanization accelerator ZnMDC 1.5 parts by weight The above materials are mixed for 15 minutes while being cooled with a two-roll mill to prepare a rubber compound, which is heat-vulcanized on the core metal at 150 ° C. for 20 minutes to obtain a thickness. A conductive substrate containing 1 mm of conductive rubber was prepared.

19) Each charging member No. 1 to 13,
The characteristics of X, Y and W are shown in Table 3.

[0166]

[Table 3]

20) Example No. 1 to 16, Comparative Example N
o. 1 to 3 in the image forming apparatus shown in FIG. 1, the photosensitive member 1 and the roller-shaped charging member (charging roller) 3 are the photosensitive member No. 2 to 4 and charging member No. 1-13, X, Y,
Example No. in which W was used in combination as shown in Table 4. 1 to
16, Comparative Example No. Performance evaluation of 1-3 was performed.

In this case, the wavelength of light for image exposure and pre-exposure was set to 660 nm. The charging part is configured such that the core metal parts on both sides are pressed against the photoconductor by the springs (total pressure 15.69N on both sides, 7.8N on one side) against the photoconductor 1.
Then, the photosensitive member 1 is charged by applying a charging voltage to the cored bar 31 while being driven to rotate. The charging voltage is −
A sine wave of 1600Vpp / 1840Hz is superimposed on a DC voltage of 650V. DC component of developing voltage is -350V
And

.. Evaluation method 1 Using the above-mentioned image forming apparatus, 100,000 continuous A4 sheets were continuously printed at a printing ratio of 5% in an environment of 30 ° C./85% RH, and image formation was performed on the film thickness of the photoconductor at the beginning of durability and after durability. Area and the non-image forming area (especially the end portion of the charging member), the respective scraped amounts Zc (image area) Zr (non-image area) are calculated, and Zr / Z
The value of c was set to Z, and evaluation was performed according to the following items. The evaluation results are summarized in Table 4.

⊚: 1 ≦ Z <1.1 ○: 1.1 ≦ Z <1.2 Δ: 1.2 ≦ Z <1.3 x: 1.3 ≦ Z <1.5 xx: 1. 5 ≦ Z. Evaluation method 2 The values of Zc are summarized in Table 4. The unit of Zc is the amount of abrasion per 10,000 sheets and the unit is × 10 ^-9 m.

.. Evaluation method 3 Turn off the power of the image forming apparatus after running 100,000 sheets.
After standing for 4 hours, a character image was printed and the image deletion was evaluated according to the following items.

⊚: Good without occurrence of defective image due to image deletion ○: Level where image deletion is slight but no problem Δ: Occurrence of defective image due to image deletion is recognized to a degree ×: Image deletion is observed especially at the edge of the image Bad image occurred. Evaluation method 4 A solid black image, a halftone image, and a solid white image are formed after the durability test according to the evaluation method 1. Particularly, an image defect at the end of the image due to contamination of the exposed portion due to scattering, and a cleaning failure image due to drum fusion. The fused image was evaluated according to the following evaluation items. The evaluation results are summarized in Table 4.

⊚: Good without occurrence of defective image ◯: Slightly but no problem level Δ: Occurrence of defective image is slightly recognized ×: Many defective images occurred. Evaluation method 5 A solid white image was formed after the durability test according to the evaluation method 1, and the occurrence of vertical streak images due to defective cleaning was evaluated according to the following evaluation items, particularly at the image edges. The evaluation results are summarized in Table 4.

⊚: Good with no vertical streak image ○: Slight vertical streak but no problem level Δ: Vertical streak image is slightly observed ×: Many vertical streak images are generated. Evaluation Method 6 A solid white image was printed after the durability test according to Evaluation Method 1, and in particular, the occurrence of a horizontal streak image due to a leak at the image end was evaluated according to the following evaluation items. The evaluation results are summarized in Table 4.

◯: Good without occurrence of horizontal streak image Δ: Level with little horizontal streak, but no problem ×: Generation of vertical streak image is confirmed. The comparative example was evaluated.

[0176]

[Table 4]

Next, examples using an organic photoconductor will be shown.

Photoconductor Production Example 5) A photoconductor is a photoconductor using an organic photoconductive substance for negative charging (hereinafter referred to as an OPC photoconductor), and four functional layers are provided on a cylinder made of aluminum having a diameter of 30 mm.

The first layer is a conductive layer, and is a conductive particle-dispersed resin having a thickness of about 20 μm, which is provided to smooth defects such as aluminum cylinders and to prevent the generation of moire due to reflection of laser exposure. It is a layer.

The second layer is a positive charge injection preventing layer (undercoat layer), which plays a role of preventing the positive charges injected from the aluminum support from canceling out the negative charges charged on the surface of the photoreceptor. -66-610-12-Medium resistance layer having a thickness of about 1 μm, whose resistance was adjusted to about 10 ⁶ Ωcm by nylon resin and methoxymethylated nylon.

The third layer is a charge generation layer, which is a layer having a thickness of about 0.3 μm in which a disazo pigment is dispersed in a resin, and positive and negative charge pairs are generated by receiving laser exposure.

The fourth layer is a charge transport layer, which is a layer having a thickness of 25 μm in which hydrazone is dispersed in polycarbonate resin, and is a P-type semiconductor. Therefore, the negative charges charged on the surface of the photoconductor cannot move in this layer, and only the positive charges generated in the charge generation layer can be transported to the surface of the photoconductor.

Each of the above layers was coated by a dipping method to obtain a photoconductor used in the examples.

Charging Member Manufacturing Example 21) ． Preparation of conductive substrate A stainless steel core having a resistance of 2Ω was prepared.

.. Adjustment of Insulating Paint on Both Ends Mixing 100 parts by weight of silicone resin and 300 parts by weight of toluene and adjusting the silicone paint, the volume resistivity was measured according to JISK6911. 1 × 10 ¹² Ωcm
Met.

.. Adjustment of rubber compound of medium resistance layer 100 parts by weight of epichlorohydrin rubber terpolymer (epichlorohydrin: ethylene oxide: allyl glycidyl ether = 40 mol%: 56 mol%: 4 mol%) light calcium carbonate 30 parts by weight plasticizer (molecular weight 8000) 10 parts by weight Stearic acid 1 part by weight Antioxidant MB 0.9 parts by weight Zinc oxide 5 parts by weight Quaternary ammonium salt 10 parts by weight 10 parts by weight of a closed type mixer adjusted to 45 ° C.
Kneading for minutes to adjust the raw material compound, and to this compound, 2 parts by weight of sulfur as a vulcanizing agent, 1 part by weight of DM as a vulcanization accelerator, and 0.5 parts by weight of TS are added to 100 parts by weight of epichlorohydrin rubber as a raw material rubber. And add 20
The mixture was kneaded for 10 minutes with a two-roll machine cooled to 0 ° C. to prepare a rubber compound.

.. Preparation of Charging Member The insulating paint prepared above was applied to both ends of the φ6 stainless steel cored bar corresponding to the non-image light image area by masking the image forming area so as to have a thickness of 20 μm. 80 after removing masking at 130 ℃
It was dried for a minute to form an insulating layer.

Using the core metal, a roller was formed by an extrusion molding machine so as to have a roller shape with an outer diameter of φ12.
It was heated and vulcanized at 50 ° C. for 2 hours to obtain a charging roller 21.

Charging Member Production Example 22). Preparation of paint for surface layer 100 parts by weight of methylolated nylon resin, toluene 15
0 parts by weight and 400 parts by weight of methanol were mixed to dissolve the resin, and 40 parts of conductive tin oxide was dispersed therein with a paint shaker for 3 hours to prepare a conductive nylon resin coating material.

.. Preparation of Charging Member A charging roller 22 similar to the charging roller 21 was obtained, except that the surface layer described above was applied to the charging roller 21 by dipping so as to have a thickness of 15 μm, and then dried at 120 ° C. for 1 hour.

Charging Member Production Example 23) The same charging as the charging roller 22 except that a fluorine tape having a thickness of 100 μm and a volume resistance value of 1 × 10 ¹⁴ Ωcm was wound around the non-image forming area of the core metal about once. Roller 23
Got

Charging Member Manufacturing Example 24) The rubber compound prepared in Charging Member Manufacturing Example 21) was
It was put in a bamboo ring-shaped mold having an outer diameter of φ14 (thickness 4.5) in the hole of No. 5, and was heated and vulcanized at 150 ° C. for 2 hours to prepare a bamboo ring-shaped rubber roller. A 100 μm thick fluorine tape was wrapped around the non-image forming area of the φ6 stainless steel core metal, and this was inserted into the bamboo ring-shaped rubber roller produced above while sending air, and then the outside Diameter is φ
Widely polished charging roller 2 to 12
Got 4.

Charging Member Production Example 25) A charging roller 25 similar to the charging roller 24 was obtained, except that a cored bar in which a 100 μm thick fluorine tape was wound around the cored bar for 4 turns was used.

Charging Member Production Example 26) Charging roller 22 except that the length of the non-image forming area is different.
A charging roller 26 similar to the above was obtained.

Charging Member Production Example 27) Charging roller 22 except that the length of the non-image forming area is different.
A charging roller 27 similar to the above was obtained.

Charging Member Production Example 28) A charging roller 28 similar to the charging roller 21 was obtained except that 1 part of the rubber compound plasticizer and 5 parts of the vulcanizing agent sulfur were used.

Charging Member Production Example 29) A charging roller 29 similar to the charging roller 21 was obtained, except that the rubber compound plasticizer was 30 parts and the vulcanizing agent sulfur was 0.5 part.

Charging Member Production Example 30) A charging roller 30 was obtained in the same manner as the charging roller 22 except that the insulating paint prepared in Charging Member Production Example 1 was applied to the cored bar portion of the non-image forming area in a thickness of 3 μm. It was

Charging Member Production Example 31) A charging roller 31 similar to the charging roller 23 was obtained except that the fluorine tape prepared in Charging Member Production Example 23 was wound around the cored bar portion of the non-image forming area for about 6 rounds.

Charging Member Production Example 32) Charging roller 22 except that the length of the non-image forming area is different.
A charging roller 32 similar to the above was obtained.

Charging Member Production Example 33) A charging roller A similar to the charging roller 22 was obtained except that the insulating coating was not applied to the cored bar.

Charging Member Production Example 34) A charging roller B was obtained by cutting the medium resistance layer of the non-image forming area of the charging roller 22 with a cutter.

Charging Member Manufacturing Example 35) The insulating coating material prepared in Charging Member Manufacturing Example 21 was applied to the medium resistance layer of the charging roller X in the non-image forming area at a thickness of 20 μm, and the coating was carried out at 130 ° C. at 40 ° C. The charging roller C dried for a minute was obtained.

Charging Member Manufacturing Example 36) Using a conductive substrate in which a conductive rubber layer having a film thickness of 1 mm was formed on a core metal made of φ6 stainless steel, and manufacturing example 21 was formed on the non-image forming area portion. A charging member 33 of φ12 was obtained in the same manner as in the charging member production example 22 except that the silicone resin paint shown in was applied so as to have a thickness of 20 μm.

EPDM 100 parts by weight Zinc oxide 5 parts by weight Higher fatty acid 1 part by weight Conductive carbon black 10 parts by weight Paraffin oil 10 parts by weight Sulfur 2 parts by weight Vulcanization accelerator MBT 1 part by weight Vulcanization accelerator TMTD 1.5 parts by weight Part vulcanization accelerator ZnMDC 1.5 parts by weight The above is mixed for 15 minutes while being cooled by a two-roll to prepare a rubber compound, which is heat-vulcanized on the above core metal at 150 ° C. for 20 minutes to give a thickness of 1 mm. An electroconductive substrate containing the electroconductive rubber of was prepared.

The characteristics of the above charging member are shown in Table 5 below.

[0207]

[Table 5]

As the electrophotographic apparatus of the present invention, a digital copying machine using a laser beam (GP55 manufactured by Canon Inc.) equipped with the image forming apparatus shown in FIG. 1 was prepared. The outline of the apparatus is provided with a corona charger as a charging means for the photoconductor, a one-component developing device adopting a one-component jumping developing method as a developing means, and a corona charger, a blade cleaning means, a pre-charge exposure as a transferring means. Means are provided. Also,
The photoconductor charger, the cleaning means, and the photoconductor are a one-body unit. Process speed is 150m
m / s. The device was modified as follows.

As the photoconductor, the photoconductor produced in the above-mentioned photoconductor production example 5 was used, and a roller charging device for contacting and charging the photoconductor at the charged portion was adjusted and mounted, and further, transfer means using a corona charger. Was changed to a roller transfer system, and a reversal development electrophotographic apparatus using a negatively chargeable photoconductor and a negatively chargeable toner was prepared.

The charged portion is such that the cored portions on both sides of the photoconductor are pressed against the photoconductor by means of springs (total pressure 15.69N on both sides, 7.8N on one side), so that the photoconductor is driven to rotate. It was decided to charge the photoreceptor by applying a charging voltage to the core metal.

The charging voltage is 220V to the DC voltage of -700V.
A 0 Vpp / 1200 Hz sine wave is superimposed. The DC component of the developing voltage was -500V.

(Evaluation Method 7) Using the above electrophotographic apparatus, 20% continuous printing on A4 landscape was carried out at a printing ratio of 5% under an environment of 30 ° C./80% RH. The film thickness is measured at the image forming portion and the non-image forming portion (especially the end portion of the charging member), and the scraped amount Zc (image portion) of each
Zr (non-image part) was calculated, and the value of Zr / Zc was set as Z, and evaluation was performed according to the following items. The evaluation results are summarized in Table 6.

⊚: 1 ≦ Z <1.1 ○: 1.1 ≦ Z <1.2 Δ: 1.2 ≦ Z <1.3 x: 1.3 ≦ Z <1.5 xx: 1. 5 ≦ Z (Evaluation method 8) Solid black after durability after evaluation method 7
Performs halftone images and solid white images, especially at the image edges, image defects due to contamination of the exposed area due to scattering,
The defective cleaning image and the fused image due to the drum fusion were evaluated according to the following evaluation items. The evaluation results are summarized in Table 6.

⊚: Good with no defective images generated ○: Slight but no problem level Δ: Occurrence of defective images is slightly recognized ×: Many defective images occurred (Evaluation method 9) After endurance according to evaluation method 7 The charging member was visually observed, and together with the image, the stain on the surface of the member was evaluated according to the following items. The evaluation results are summarized in Table 6.

⊚: Slightly soiled, no defective image due to stains on the image ○: Soil is uniformly attached, but no defective image due to stains is generated on the image Δ: Surface stain Is conspicuous, and slight image unevenness is generated on the image due to stains.
3 was used for evaluation, Comparative Examples 4 to 6 were charging members A,
Evaluation was performed using B and C.

[0216]

[Table 6]

[0217]

As described above, according to the present invention, according to the present invention, in the charging member which is disposed in contact with the member to be charged and which is charged with the charging voltage to charge the member to be charged, the charging member is at least On a conductive substrate to which a charging voltage is applied, an elastic layer having a medium electric resistance in contact with an object to be charged is provided, and the non-image forming area portions at both ends in the longitudinal direction of the object are charged. And the medium resistance layer is in contact with the medium resistance layer, and the medium resistance layer corresponding to the non-image forming area of the non-image area corresponding to the non-image forming area is formed on the conductive substrate via the electrically insulating layer. By using, the discharge amount at the edge is reduced, and the potential on the charged body gradually decreases from the image area toward the edge, so that the local abrasion of the photoconductor at the edge is reduced and the potential difference is reduced. Toner can be prevented from migrating to the edges due to Since the inner contamination is reduced, it becomes possible to extend the life of the photosensitive member, it is possible to provide a charging member which good images can be obtained over a long period.

When an amorphous silicon type photosensitive member is used, the discharge amount at the end is reduced by using the charging member, deterioration of the charging member is prevented, image deletion at the end and image portion on the surface of the photosensitive member are prevented. Since the difference in frictional force between the non-image forming part and the non-image forming part is small, a defective image such as poor cleaning is prevented, and the potential on the charged body gradually decreases from the image area toward the end part. The local abrasion of the photoconductor is reduced, and the transfer of toner to the edge due to the potential difference can be prevented, which reduces the contamination in the machine such as scattering, which can prolong the life of the photoconductor and provide a good image for a long time. Is obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration model diagram of an example of an image forming apparatus.

FIG. 2 is a structural model diagram of a blade-shaped charging member.

FIG. 3 is a structural model diagram of a roller-shaped charging member.

FIG. 4 is a diagram showing a potential state in the longitudinal direction of the photoconductor.

FIG. 5A and FIG. 5B are schematic layer structure diagrams of an amorphous silicon-based photoconductor as a light receiving member.

FIG. 6 is a schematic configuration diagram of an example of a deposition apparatus used for manufacturing a light receiving member by the PCVD method.

FIG. 7 is a schematic configuration diagram of another example of a deposition apparatus used for manufacturing a light receiving member by the PCVD method.

[Explanation of symbols]

101 Conductive Substrate 102 Charge Injection Blocking Layer 103 Photoconductive Layer 104 Surface Layer 105 Charge Generation Layer 106 Charge Transport Layer 2100, 3100 Deposition Device 2110, 3110 Reaction Vessels 2111, 3111 Cathode Electrodes 212, 3112 Conductive Substrate 2113, 3113 Substrate Heating Heaters 2114, 3114 gas introduction pipes 2115, 3115 high frequency matching boxes 2116, 3116 gas pipes 2117, 3117 leak valves 2118, 3118 main valves 2119, 3119 vacuum systems 2120, 3120 high frequency power supplies 2121, 3121 insulating material 3122 insulating shield plate 2123 3123 Cradle 2200, 3200 Gas supply device 2211-2216, 3122-3216 Mass flow controller 2221-2226, 3221-3226 Valves 2231-2236, 3231-3236 valves 2241-2246, 3241-3246 inflow valves 2251-2256, 3251-3256 outflow valves 2260, 3260 auxiliary valves 2261-2266, 3261-3266 pressure regulator 1: photoconductor 3: charging member 31: conductive substrate 32: medium resistance layer 33: insulating layer a: image forming area b: non-image forming area

Continued front page    F-term (reference) 2H068 CA03 DA05 DA12 DA28 DA53                 2H200 FA08 FA09 FA19 GA16 GA18                       GA23 HA02 HA28 HB12 HB14                       HB22 HB40 HB43 HB45 HB46                       HB47 MA01 MA03 MA04 MB02                       MB03 MB06 MC02

Claims (19)

[Claims] 1. A charging member for charging an image bearing member by bringing it into contact with the image bearing member and applying a voltage thereto, and an electric resistance contacting the image bearing member is provided on at least a conductive substrate to which a charging voltage is applied. It is configured to have an elastic layer having a medium resistance, and the medium resistance elastic layer also contacts the non-image forming area portion at the end portion in the longitudinal direction of the image carrier, and the medium resistance elastic layer corresponding to the non-image forming area is A charging member, characterized in that it is formed on a conductive substrate through an electrically insulating layer. 2. The charging member according to claim 1, wherein the medium resistance elastic layer corresponding to the non-image forming area has a longitudinal length of 3 mm or more. 3. The charging member according to claim 1, wherein the thickness of the electrically insulating layer in the portion corresponding to the non-image forming area is 1/10 or less of the thickness of the medium resistance elastic layer. . 4. The charging member according to claim 1, wherein the electrically insulating layer in the portion corresponding to the non-image forming region has a film thickness of 5 μm to 500 μm. 5. The hardness of the medium resistance elastic layer is JIS K63.
35 to 75 at the hardness specified by the 01 type A hardness tester
The charging member according to claim 1, which is an elastic body having a degree. 6. The electrically insulating layer in a portion corresponding to the non-image forming area is a layer formed by applying an insulating coating material on a conductive substrate. The charging member described. 7. The electrically insulating layer in the portion corresponding to the non-image forming area is a layer formed by covering a conductive substrate with an insulating sheet or tape. The charging member according to any one of claims. 8. A step of charging a photoreceptor by bringing a charging member into contact with the photoreceptor to apply a voltage, and a latent image forming step of forming an electrostatic latent image on the photoreceptor by performing image exposure. An image forming apparatus having a developing step of visualizing the electrostatic latent image with toner and a step of transferring the toner image onto a transfer material, wherein the photoconductor is an amorphous silicon photoconductor, and the charging member is at least a charging voltage. A conductive substrate to which is applied is provided with an elastic layer having an electric resistance of medium resistance in contact with the photoconductor, and the non-image forming area portion at the longitudinal end of the photoconductor also has the medium resistance. An image forming apparatus, wherein the elastic layers are in contact with each other, and the medium resistance elastic layer corresponding to the non-image forming area is formed on the conductive substrate via an electrically insulating layer. 9. The amorphous silicon-based photoconductor has a photoconductive layer formed of a non-single-crystal material having silicon atoms as a base material on a conductive substrate. Image forming device. 10. The image forming apparatus according to claim 8, wherein the medium resistance elastic layer corresponding to the non-image forming area has a length of 3 mm or more in the longitudinal direction. 11. The film thickness of the electrically insulating layer in the portion corresponding to the non-image forming area is 1/10 or less of the film thickness of the medium resistance elastic layer, according to any one of claims 8 to 10. Image forming device. 12. The image forming apparatus according to claim 8, wherein the film thickness of the electrically insulating layer in the portion corresponding to the non-image forming area is 5 μm to 500 μm. 13. The medium resistance elastic layer has a hardness of JIS K6.
35 to 7 at the hardness specified by 301 type A hardness tester
The image forming apparatus according to claim 8, wherein the image forming apparatus is an elastic body having 5 degrees. 14. The non-image forming area corresponding to the electrically insulating layer is a layer formed by applying an insulating coating material on a conductive substrate. The image forming apparatus described. 15. The electrically insulating layer in the portion corresponding to the non-image forming area is a layer formed by covering an electrically conductive substrate with an insulating sheet or tape.
The image forming apparatus according to any one of 3 above. 16. The image forming apparatus according to claim 8, wherein the photoconductor is an amorphous silicon photoconductor having a surface layer formed of a non-single crystalline hydrogenated carbon film. . 17. The image forming apparatus according to claim 16, wherein the amount of hydrogen in the non-single crystalline hydrogenated carbon film is 41% to 60%. 18. The image forming apparatus according to claim 8, wherein the photoconductor is composed of three layers of a charge injection blocking layer, a photoconductive layer and a surface layer. 19. The image according to claim 8, wherein the photoconductor is composed of four layers of a charge injection blocking layer, a charge transport layer, a charge generation layer and a surface layer. Forming equipment.