JP2000284661A - Image forming device and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the turn-up of a cleaning member over a long term without causing faulty electrification even in the case of using a contact electrifying means. SOLUTION: An electrifying roller 2 uniformly electrifying the surface of a photoreceptor drum 1 is arranged in contact with the surface of the drum 1. A grinding member 14 (surface roughing means) roughing one part of the surface of the drum 1 is provided on a downstream side from the roller 2 and on an upstream side from a cleaning means 8 in the rotating direction (direction shown by an arrow (a)) of the drum 1. At least one part of a part inside from a cleaning area where a cleaning blade 6 abuts and outside from a developing area where development is performed by a developing means 5 out of the surface of the drum 1 is roughed by the member 14. Thus, the frictional force of the blade 6 exerted on the surface of the drum 1 is weakened so as to prevent the turn-up of the blade.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus having a cleaning blade for removing toner and the like adhering to the surface of an electrophotographic photosensitive member by rubbing, and is detachable from the image forming apparatus. Regarding the process cartridge.

[0002]

2. Description of the Related Art FIG. 5 is a longitudinal sectional view showing a schematic structure of a process cartridge used in a conventional electrophotographic image forming apparatus. In the process cartridge shown in the figure, several process devices (image forming means) are integrated into a cartridge container to be made into a compact cartridge.

In FIG. 1, reference numeral 1 denotes a photosensitive drum as an electrophotographic photosensitive member, 2 denotes a charging roller as a contact charging means disposed in contact with the surface of the photosensitive drum 1 to uniformly charge the surface, and 5 denotes a photosensitive drum. Developing means 8 for attaching toner to the electrostatic image formed on the surface of the photosensitive drum 1 to form a toner image (developed image), and cleaning means 8 for removing and collecting the toner remaining on the surface of the photosensitive drum 1. The photosensitive drum 1, the charging roller 2, the developing means 5, the cleaning means 8 and the like are integrated into a housing (cartridge container) 9 to form a cartridge, thereby forming a compact process cartridge 11.

The developing means 5 has a developing sleeve 3 which rotates in the direction of arrow B to convey toner, and a developing blade 4 for regulating the thickness of the toner on the developing sleeve 3.

A transfer roller 10 is provided below the photosensitive drum 1 as transfer means for applying a charge to the transfer material P and electrostatically transferring the toner image on the photosensitive drum 1 to the transfer material P. ing.

The transfer material P carrying on its surface the unfixed toner image transferred by the transfer roller 10 is conveyed to a fixing means (not shown) and is fixed by heating and pressing of the fixing means.

The cleaning means 8 includes a cleaning blade 6 supported by a support member 13 for scraping off the transfer residual toner from the photosensitive drum 1 and a toner receiving sheet 7 for collecting the scraped transfer residual toner. In addition, a blade end seal (not shown) such as foamed polyurethane is provided at both ends of the cleaning blade 6 in a gap between the cleaning blade 6 and the container of the cleaning means 8.

The cleaning blade 6 generally uses a highly durable urethane rubber. In addition, urethane rubber has a high degree of adhesion and a high scraping force for toner, but on the other hand, has poor slipperiness with respect to a contacting member due to the adhesion. When the photosensitive drum 1 rotates, the cleaning blade 6 receives a force in the direction indicated by an arrow F in FIG. 6, but is in contact with the surface of the photosensitive drum 1 in the counter direction. If the frictional force between them becomes excessively large, the edge of the cleaning blade 6 is reversed in the direction of the arrow F with the operation of the photosensitive drum 1 (rotation in the direction of the arrow a), so that a so-called "blade turning phenomenon" occurs. There is.

Therefore, in order to deal with such a problem,
There is a method in which silicon resin fine particles or fluorine particles as a lubricant are applied to a contact portion with the photosensitive drum 1 to enhance lubricity. However, since this lubricant is peeled off from the cleaning blade 6 and decreases over a long period of use, the effect of preventing the blade from turning over cannot be maintained for a long period of time.

The following method is known as another example of the solution to this problem. Usually, the surface of the photosensitive drum 1 is almost mirror-finished in manufacturing. For this reason, the cleaning blade 6 comes into close contact with the photosensitive drum 1, and very large frictional resistance is likely to occur. However, if the surface of the photosensitive drum is intentionally roughened within a range where there is no problem in image formation, the contact area between the cleaning blade 6 and the photosensitive drum 1 is reduced, and the frictional force is also reduced. It is possible to prevent the frictional force between the photosensitive drum 1 and the cleaning blade 6 from being excessively roughened to some extent.

For example, JP-A-08-095258 and JP-A-11-002910 disclose a photosensitive drum 1 in which the surface of the photosensitive drum 1 contacting near the blade end is particularly roughened at the end from the intermediate part. It has been disclosed.

This prevents noise caused by the vibration of the cleaning blade 6 in contact with the end surface of the photosensitive drum 1, and the side end of the cleaning blade 6, which is a free end, is more easily turned up than the intermediate portion. This is to prevent blade turning. That is, the contact area between the cleaning blade 6 and the photosensitive drum 1 decreases,
Since the frictional force is reduced, the surface of the photosensitive drum 1 can be roughened to some extent, and the frictional force between the photosensitive drum 1 and the cleaning blade 6 can be prevented from becoming excessive.

Japanese Patent Laid-Open No. 10-340027 discloses a photosensitive drum 1 as a polishing member for the surface of the photosensitive drum 1.
There is disclosed a polishing member in which the polishing characteristics of an end polishing portion for polishing the width direction end portion and a central polishing portion for polishing the center portion of the photosensitive drum 1 are different from each other so that the end portion has a larger surface roughness than the center portion. ing. In this case, since the side end of the cleaning blade 6 is a free end, it is more easily turned up than the intermediate part. Therefore, a polishing member is provided for the purpose of roughening the surface of the photosensitive drum as described above.

Further, Japanese Patent Application Laid-Open No. 62-182785 discloses that a toner is developed on the edge of the sheet width to remove talc adhering to the surface of the photosensitive drum 1 together with the toner. Talc is removed from the surface of the photosensitive drum 1 to prevent image deletion. This is
This is a method of polishing the surface of the photosensitive drum 1 in the development area, and the method is obviously different from the method of polishing the surface of the photosensitive drum 1 outside the development area of the present invention.

[0015]

However, the method disclosed in Japanese Patent Laid-Open No.
8-095258 and JP-A-11-002910
The method described in Japanese Patent Application Laid-Open Publication No. H10-15095 in which the surface of the photosensitive drum 1 is roughened in advance to prevent the blade from turning up also has the following problems.

Since the surface of the photosensitive drum is abraded as the endurance advances, the roughness of the photosensitive drum is reduced as much as in the initial stage of use.
The end of the cleaning blade 6 may be turned up. In other words, if the surface is only roughened in advance, the blade is turned over after a long use.

Further, the surface of the photosensitive drum 1 is polished by a polishing member as disclosed in Japanese Patent Application Laid-Open No. H10-340027,
Regarding the method of increasing the roughness near the end, the end roughness can be maintained to some extent, and blade turning can be continuously prevented. However, when the contact charging means is used as the charging means as in the present invention, it is not necessary to provide the shaving powder at a position downstream of the cleaning means when viewed in the operation direction of the photosensitive drum 1 so that the shaving powder is removed.
, Causing poor charging.

The charging roller 2 is in pressure contact with the surface of the photosensitive drum 1 by springs (not shown) at both ends thereof, and is driven to rotate as the photosensitive drum 1 rotates. That is, since the pressing force is higher at both ends than at the center, the surface material of the charging roller 2 is slightly rubbed against the surface of the photosensitive drum 1 and transferred, particularly at both ends. This causes the surface of the photosensitive drum 1 to be less slippery and causes blade turning.

In addition to the end portions, especially the transfer roller 1
0 is in contact with the surface of the photosensitive drum 1 and the transfer roller 10
It itself cleans the surface of the photosensitive drum 1, and further inside, the toner image and the transfer material P are cleaning, that is, the outside of the portion of the photosensitive drum surface that is in contact with the transfer roller 10. The portion where only the charging roller 2 comes into contact is particularly hard to slip, which is a trigger for turning up the blade.

[0020]

According to a first aspect of the present invention, there is provided an electrophotographic photosensitive member for carrying an electrostatic image, and the electrophotographic photosensitive member in contact with the electrophotographic photosensitive member. Contact charging means for uniformly charging the body surface; developing means for developing the electrostatic image on the electrophotographic photosensitive member as a developed image; and electrophotographic photosensitive member in a counter direction as viewed in the operation direction of the electrophotographic photosensitive member. A cleaning blade that removes deposits on the surface of the electrophotographic photoreceptor by a leading edge that contacts the body surface. The surface of the electrophotographic photoreceptor is contacted to roughen at least a part of the inner side and at least a part of a part outside a developing area where development is performed by the developing unit. The roughening means is, is disposed upstream of the downstream side a and the cleaning blade than the contact charging means viewed in the direction of movement of said electrophotographic photosensitive member,
It is characterized by the following.

According to a second aspect of the present invention, in the image forming apparatus of the first aspect, a transfer electric field is formed between the electrophotographic photosensitive member and a transfer material to transfer the developed image on the electrophotographic photosensitive member. Transfer means for electrostatically transferring to the transfer material, wherein the transfer means is applied with a voltage having a polarity opposite to the polarity charged by the contact charging means inside a charging area of the contact charging means; It is characterized by.

According to a third aspect of the present invention, in the image forming apparatus of the second aspect, the roughening means is provided at least outside a transfer area of the transfer means.

According to a fourth aspect of the present invention, in the image forming apparatus of the first or second aspect, the roughening means is provided at least inside a charging area of the contact charging means. Features.

The present invention according to claim 5 is based on claims 1, 2,
In the image forming apparatus according to the third or fourth aspect, the surface roughening means has a polishing layer using an abrasive on a surface.

The present invention according to claim 6 is based on claims 1, 2,
In the image forming apparatus according to the third or fourth aspect, the surface roughening unit includes a support and a polishing sheet attached to a surface of the support.

The present invention according to claim 7 is based on claims 1, 2,
3, 4, 5 or 6, wherein the transfer means is a transfer roller, and the surface roughening means is provided on an outer peripheral surface near an end of the transfer roller. I do.

The present invention according to claim 8 is the invention according to claims 1, 2,
In the image forming apparatus of any one of 3, 4, 5, 6 and 7, the surface roughening means is integrally incorporated in a process cartridge including at least the electrophotographic photosensitive member and detachable from an image forming apparatus main body. , Characterized in that.

According to a ninth aspect of the present invention, there is provided an electrophotographic photosensitive member carrying at least an electrostatic image, a contact charging means for contacting the electrophotographic photosensitive member and uniformly charging the surface of the electrophotographic photosensitive member, Developing means for developing the electrostatic image on the electrophotographic photosensitive member as a developed image; and a carrier having a leading edge which abuts on the surface of the electrophotographic photosensitive member in a counter direction as viewed in the operation direction of the electrophotographic photosensitive member. In a process cartridge, which is used in an image forming apparatus having a cleaning blade for removing an adhered substance on a surface, and is detachable from the main body of the image forming apparatus, the cleaning blade of the electrophotographic photosensitive member has a cleaning blade. At least a part of a portion inside a cleaning region that is in contact with and outside a developing region where development is performed by the developing unit is roughened. A surface roughening unit, wherein the surface roughening unit is disposed downstream of the contact charging unit and upstream of the cleaning blade when viewed in the operation direction of the electrophotographic photosensitive member. .

According to a tenth aspect of the present invention, in the process cartridge of the ninth aspect, the image forming apparatus main body to which the process cartridge is attached / detached imparts a charge to a transfer material to cause a transfer member to be mounted on the electrophotographic photosensitive member. A transfer unit that electrostatically transfers the developed image to the transfer material, wherein a voltage having a polarity opposite to a polarity charged by the contact charging unit is applied to the inside of a charging area of the contact charging unit; It is characterized by that.

The present invention according to claim 11 is the process cartridge according to claim 9 or 10, wherein the surface roughening means is provided at least outside a transfer area of the transfer means.

According to a twelfth aspect of the present invention, in the process cartridge of the ninth or tenth aspect, the surface roughening means is provided at least inside a charging area of the contact charging means. .

According to the thirteenth aspect, the present invention provides a ninth aspect,
Process cartridge 0, 11 or 12, wherein the surface roughening means has a polishing layer using an abrasive on the surface.

According to a fourteenth aspect of the present invention, there is provided the ninth and the first aspects.
0, 11, or 12 process cartridges,
The roughening means includes a support and a polishing sheet attached to a surface of the support.

[0034]

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

<Embodiment 1> FIG. 1 shows an example of an image forming apparatus according to the present invention. FIG. 1 is a longitudinal sectional view showing a part of the image forming apparatus.

The image forming apparatus shown in FIG. 1 includes a drum type electrophotographic photosensitive member (hereinafter, referred to as "photosensitive drum") 1 as an image carrier. The photosensitive drum 1 is rotationally driven (operates) in a direction indicated by an arrow a by a driving unit (not shown).

Around the photosensitive drum 1, a charging roller 2 serving as a contact charging means for charging the surface of the photosensitive drum 1 to a uniform potential substantially in the direction of rotation thereof, and a surface of the charged photosensitive drum 1. Exposure means 1 for exposing to form an electrostatic image
2. Developing means 5 for adhering toner to the electrostatic image formed on the surface of photosensitive drum 1 to form a toner image, and toner remaining on the surface of photosensitive drum 1 (residual toner) scraped by cleaning blade 6. A cleaning means 8 for removing and collecting the residual toner is provided.

The above-mentioned charging roller 2 is arranged in contact with the surface of the photosensitive drum 1, and is driven to rotate in the direction of the arrow c with the rotation of the photosensitive drum 1 in the direction of the arrow a. A charging bias application power source S is connected to the charging roller 2 so that a charging bias in which a DC voltage and an AC voltage are superimposed is applied. Development means 5 described above
Has a developing sleeve 3 that carries toner on the surface and rotates in the direction of arrow b, and a developing blade 4 that regulates the layer thickness of the toner on the surface of the developing sleeve 3. The cleaning blade 6 has a leading edge 6a that comes into contact with the surface of the photosensitive drum 1 in the counter direction when viewed in the rotation direction of the photosensitive drum 1.

The photosensitive drum 1, the charging roller 2, the developing means 5, the cleaning means 8 and the like among the above-mentioned members are integrated into a housing (cartridge container) 9 to form a cartridge, and a compact process cartridge is provided. 11. The process cartridge 11 can be easily attached to and detached from an image forming apparatus main body (not shown).
A transfer roller 10 serving as a transfer charging unit for transferring a toner image on the surface of the photosensitive drum 1 onto the transfer material P is provided below the photosensitive drum 1 in a state where is mounted. The transfer material on which the toner image has been transferred to the surface by passing through the transfer roller 10 is transported to a fixing unit (not shown) while carrying the unfixed toner image, and is heated and pressurized here. The toner image is fixed on the surface. Transfer material P after toner image fixing
Is discharged onto a paper discharge tray (not shown).

FIG. 2 shows the photosensitive area A of the photosensitive drum 1 and the charging area A of the charging roller 2 serving as the contact charging means, the transfer area B of the transfer roller 10, the cleaning area C of the cleaning blade 6, and the developing area E of the developing sleeve 3. The positional relationship in the longitudinal direction (width direction) of the drum 1 is shown. The photosensitive drum 1, the cleaning area C, the charging area A, the transfer area B, and the developing area E are arranged in the order of width. In addition, the surface potential of the photosensitive drum 1 in the longitudinal direction is also shown for areas other than the development area E.

In this embodiment, a polishing member 14 is provided as a roughening means for roughening the surface of the photosensitive drum 1. The polishing member 14 is disposed downstream of the transfer unit 10 and upstream of the cleaning unit 8 in the rotation direction of the photosensitive drum 1 (direction of arrow a). That is, it is disposed downstream of the charging roller 2 as a contact charging unit and upstream of the cleaning unit 8. The polishing member 14 has on its surface a polishing layer formed by mixing an abrasive with an elastic material such as resin or rubber.
The surface of the photosensitive drum 1 may be slightly scraped by pressing against the surface, or by rotating a roller or the like wound with something like sandpaper. When the above-mentioned sandpaper is used, it is appropriate that the sandpaper is approximately No. 1000 of JIS standard or slightly coarser.

The above-mentioned polishing member 14 is desirably brought into contact with the vicinity of both ends in the longitudinal direction of the surface of the photosensitive drum 1, that is, an area where an electrostatic image is not developed by the developing means 5 and an image cannot be formed. In a region where an image is formed, if the surface of the photosensitive drum 1 is too rough, a good image cannot be obtained. Therefore, the surface roughness (10-point average roughness: the same applies hereinafter) must be 1 μm or less. However, since the area near the end of the cleaning blade 6 is a non-image forming area, there is no problem even if the surface roughness is about 5 μm, and a range in which the surface layer of the photosensitive drum 1 is not excessively shaved. Can be used coarsely.

As described above, according to the present invention, the surface roughness of the photosensitive drum 1 can be maintained so that the cleaning blade 6 does not turn over. A good image can be formed without turning over.

The cleaning blade 6 at the beginning of use is used.
In order to prevent the curling, it is considered that the most effective form is to use the lubricant and the toner in advance in a powder form on the surface of the cleaning blade 6 or the photosensitive drum 1 as in the related art. .

However, when an image forming method called a so-called reversal developing method is employed, usually, the charging means such as the charging roller 2 charges a wider area than the transfer means such as the transfer roller 10. So, as shown in Figure 2,
Of the areas (charged area A) that are negatively charged by the charging roller 2, for example, the area that receives positive charge by the transfer roller 10 (transfer area B) is close to 0 V during cleaning. In the region (region D) not receiving the positive charge, the negative charge remains even when facing the cleaning blade 6.

On the other hand, some lubricants, which are present as powder and are usually negatively charged, rub against each other, causing some of the lubricants to be positively charged.

The positively charged lubricant is attracted to the region D in FIG. 2 and is transferred from the cleaning blade 6 to the surface of the photosensitive drum 1. When this phenomenon progresses and the lubricant of the cleaning blade 6 decreases excessively, blade turning occurs. That is, in order to prevent the cleaning blade 6 from being turned up, at least a portion of the non-image forming area (outside of the developing area E) on the surface of the photosensitive drum 1 which is located outside the transfer area B and inside the charging area A. If the surface property of (region D) is roughened, there is a sufficient effect.

Therefore, especially in an image forming apparatus adopting the reversal development system, the polishing member 14 (roughening means) as in the present invention is more effective than preventing the cleaning blade 6 from being turned only by applying a lubricant. It is preferable to use them together, and if both the use of the lubricant and the roughening of the photosensitive drum 1 are used in this way, the effect of preventing the blade from being turned up can be further enhanced.

In this embodiment, the polishing member 14 (roughening means) is located downstream of the transfer roller 10 and upstream of the cleaning blade 6 with respect to the rotation direction of the photosensitive drum 1 (direction of arrow a). This is because powder or the like generated by polishing may adhere to the charging roller 2 and cause charging failure, that is, on the upstream side of the cleaning blade 6 and the charging roller 2. 2 is satisfied, the shavings of the photosensitive drum 1 do not adhere to the charging roller 2, and therefore, poor charging and blade turning can be prevented.

In particular, if the polishing member 14 (roughening means) is disposed immediately before the cleaning means 8, the powder generated by polishing can be collected by the cleaning means 8 before being transferred to other parts. Since the inside of the image forming apparatus main body is not contaminated, it is preferable that the image forming apparatus is disposed downstream of the transfer roller 10 and upstream of the cleaning blade 6 as in the above-described embodiment.

<Second Embodiment> Next, a second embodiment will be described with reference to FIG.

In the present embodiment, the polishing member 14 as a roughening means is attached to the developing container 5a of the developing means 5 incorporated in the process cartridge 11. In addition, in each member in FIG. 3, those having the same configuration and operation as those in FIG.
A duplicate description of these will be omitted as appropriate.

In this embodiment, the developing container 5a of the process cartridge 11 which can be attached to and detached from the image forming apparatus main body is
Since the polishing member 14 (roughening means) is provided, and the polishing member 14 is replaced with a new one when the process cartridge 11 is replaced, the surface of the photosensitive drum 1 can be stably roughened for a long time. it can. For example, if the performance of the polishing member 14 deteriorates, sufficient performance may not be obtained. Therefore, it is desirable that the polishing member 14 can be replaced at appropriate time intervals. In such a case, the polishing member 14 can be replaced without performing a special operation for replacing the polishing member 14, and a good polishing action can always be exhibited.

In the above-described embodiment, the polishing member 14
Is attached to the lower portion of the developing container 5a of the process cartridge 11, but is not limited to this. For example,
An exchangeable cleaning container and other photosensitive drums around the photosensitive drum 1 are provided on the condition that the condition that the downstream side of the charging roller 2 and the upstream side of the cleaning blade 6 are satisfied along the rotation direction of the photosensitive drum 1 is satisfied. You may make it comprise integrally with a replacement part.

Third Embodiment FIG. 4 shows a third embodiment.

In this embodiment, the surface roughening means is formed coaxially with the transfer roller 20 and is formed as a single component. Except for this point, the other configuration is the same as that shown in FIG. 1. Therefore, hereinafter, only the transfer portion 16 and the roughened portion 15 of the transfer roller 20 are shown, and other members such as Is omitted.

The surface roughening portion 15 of the transfer roller 20 as a surface roughening means includes a cylindrical roller body 20 as a support.
A polishing layer in which an abrasive capable of polishing the surface of the photosensitive drum 1 is mixed is provided on the outermost layer of A, and roughened portions 15 are formed at both ends in the longitudinal direction of the transfer roller 20. In addition, a polishing sheet such as sandpaper may be adhered to the outer peripheral surfaces at both ends of the roller body 20A to form the roughened portion 15.

According to the present embodiment, there is no need to make a change such as preparing a space for installing a new roughening means or a separate member, and the effect obtained from the arrangement is the same as that of the first embodiment. It is preferred because it is similar.

In order to prevent an excessive current from flowing to a portion of the surface of the photosensitive drum 1 where the surface layer is roughened and the resistance becomes low, the roughening portion 15 of the transfer roller 20 is connected to the transfer portion 1.
The transfer current may be prevented from flowing through the roughened portion 15 by setting the resistance sufficiently higher than 6 or by providing an interval of about 2 mm between the transfer portion 16 and the roughened portion 15.

In the above embodiment, an example is shown in which the present invention is applied to an electrophotographic photosensitive member as an image bearing member. The present invention is also applicable to a member such as a so-called intermediate transfer body (for example, an intermediate transfer belt or an intermediate transfer drum) onto which an image is transferred.

[0061]

As described above, according to the present invention,
By providing a roughening means for roughening the surface of the electrophotographic photoreceptor on the downstream side of the contact charging means and on the upstream side of the cleaning means when viewed in the direction of operation of the electrophotographic photoreceptor, contact charging is performed. Even when the means is used, turning over of the cleaning member is prevented for a long time without causing charging failure.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view illustrating a schematic configuration of an image forming apparatus according to a first embodiment.

FIG. 2 is a schematic diagram showing the width of each member in the longitudinal direction of the photosensitive drum and the photosensitive drum surface potential at a cleaning blade contact position.

FIG. 3 is a longitudinal sectional view illustrating a schematic configuration of an image forming apparatus according to a second embodiment.

FIG. 4 is a perspective view showing an embodiment in which a surface roughening means is provided on a charging roller.

FIG. 5 is a longitudinal sectional view showing a schematic configuration of a conventional image forming apparatus.

[Explanation of symbols]

Reference Signs List 1 electrophotographic photosensitive member (photosensitive drum) 2 contact charging means (charging roller) 5 developing means (developing device) 6 cleaning blade 6a leading edge 8 cleaning means 10 transfer means (transfer roller) 11 process cartridge 14 roughening means (polishing) 15) Roughening part (polishing layer, polishing sheet) 16 Transfer part 20 Transfer means (transfer roller) 20a Supporter (roller body) A Charged area a Operation direction (rotation direction) of electrophotographic photosensitive member (photosensitive drum) ) B transfer area C cleaning area E development area P transfer material

Claims (14)

[Claims] An electrophotographic photoreceptor carrying an electrostatic image; contact charging means for contacting the electrophotographic photoreceptor and uniformly charging the electrophotographic photoreceptor surface; A developing means for developing the electrophotographic image as a developed image and a tip edge contacting the electrophotographic photosensitive member surface in a counter direction as viewed in the operation direction of the electrophotographic photosensitive member to remove deposits on the surface of the electrophotographic photosensitive member. A cleaning blade, wherein a portion of the surface of the electrophotographic photosensitive member, which is inside a cleaning region where the cleaning blade contacts, and outside a development region where development is performed by the developing unit. Surface roughening means contacting the surface of the electrophotographic photosensitive member so as to roughen at least a part of the surface of the electrophotographic photosensitive member; Than downstream and the cleaning blade than stage is disposed on the upstream side, an image forming apparatus characterized by. 2. A transfer means for forming a transfer electric field between the electrophotographic photosensitive member and a transfer material to electrostatically transfer the developed image on the electrophotographic photosensitive member to the transfer material, 2. The image forming apparatus according to claim 1, wherein the transfer unit applies a voltage having a polarity opposite to a polarity charged by the contact charging unit inside a charging area of the contact charging unit. 3. 3. The image forming apparatus according to claim 2, wherein the roughening unit is provided at least outside a transfer area of the transfer unit. 4. The image forming apparatus according to claim 1, wherein the surface roughening unit is provided at least inside a charging area of the contact charging unit. 5. The image forming apparatus according to claim 1, wherein the surface roughening means has a polishing layer using a polishing material on a surface. 6. The method according to claim 1, wherein the roughening means has a support and a polishing sheet attached to a surface of the support. Image forming device. 7. The transfer device according to claim 1, wherein the transfer unit is a transfer roller, and the surface roughening unit is provided on an outer peripheral surface near an end of the transfer roller. 7. The image forming apparatus according to 4, 5, or 6. 8. The image forming apparatus according to claim 1, wherein the surface roughening unit is integrated into a process cartridge including at least the electrophotographic photosensitive member and detachable from an image forming apparatus main body. 2, 3, 4, 5, 6 or 7
An image forming apparatus according to claim 1. 9. An electrophotographic photosensitive member carrying at least an electrostatic image, contact charging means for contacting the electrophotographic photosensitive member and uniformly charging the surface of the electrophotographic photosensitive member, and Developing means for developing the electrostatic image as a developed image;
A cleaning blade having a leading edge contacting the electrophotographic photoreceptor surface in a counter direction as viewed in the operation direction of the electrophotographic photoreceptor, and removing a deposit on the surface of the carrier. A process cartridge detachable from the image forming apparatus main body, wherein a portion of the electrophotographic photosensitive member surface, which is inside a cleaning region where a cleaning blade contacts, and a developing region where development is performed by the developing unit. A surface roughening means for roughening at least a part of the outer part, wherein the roughening means is downstream from the contact charging means and from the cleaning blade when viewed in the operation direction of the electrophotographic photosensitive member. A process cartridge also disposed upstream. 10. The image forming apparatus main body to which the process cartridge is attached and detached, applies an electric charge to a transfer material,
Transfer means for electrostatically transferring the developed image on the electrophotographic photoreceptor to the transfer material, wherein the transfer means has a charge polarity by the contact charging means inside a charging area of the contact charging means; The process cartridge according to claim 9, wherein a voltage having a reverse polarity is applied. 11. The process cartridge according to claim 9, wherein the surface roughening means is provided at least outside a transfer area of the transfer means. 12. The process cartridge according to claim 9, wherein the surface roughening means is provided at least inside a charging area of the contact charging means. 13. The process cartridge according to claim 9, wherein the surface roughening means has a polishing layer using an abrasive on the surface. 14. The method according to claim 9, wherein the surface roughening means has a support and a polishing sheet attached to a surface of the support. Process cartridge.