阅读说明：本技术 电子照相感光构件、处理盒和电子照相设备 (Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus ) 是由 上野高典 滝泽久美子 黑岩育世 嶋田刚志 北村航 竹内艾琳 于 2019-06-04 设计创作，主要内容包括：本发明涉及电子照相感光构件、处理盒和电子照相设备。提供一种能够抑制干涉条纹和图像上沿圆周方向的条纹状不均匀部分二者的产生的电子照相感光构件。通过限定支承体的沿圆周方向的线状沟槽的长度,和限定支承体的沿轴向的粗糙度参数,来抑制干涉条纹的产生和图像上沿圆周方向的条纹状不均匀部分的产生。(The invention relates to an electrophotographic photosensitive member, a process cartridge, and an electrophotographic apparatus. Provided is an electrophotographic photosensitive member capable of suppressing the generation of both interference fringes and a striped uneven portion in the circumferential direction on an image. The generation of interference fringes and the generation of a striped unevenness in the circumferential direction on an image are suppressed by defining the length of a linear groove in the circumferential direction of a support body and defining a roughness parameter in the axial direction of the support body.)

1. An electrophotographic photosensitive member comprising a cylindrical support, an undercoat layer and a photosensitive layer in this order,

Characterized in that the surface of the support comprises linear grooves along the circumferential direction of the support, when a represents the length of the linear grooves along the circumferential direction, the length a satisfies 50 [ mu ] m

Wherein a ten-point average roughness Rzjis, an average length of a roughness curve element Rsm and a skewness Rsk, which are obtained from a roughness curve of the surface of the support body in the axial direction according to JIS B0601:2001, respectively satisfy

0.7μm≤Rzjis，

Rsm is less than or equal to 50 μm, and

-4.0≤Rsk≤-0.2。

2. The electrophotographic photosensitive member according to claim 1, wherein the skewness Rsk of the support is in the range of-1.2. ltoreq. rsk.ltoreq-0.2.

3. The electrophotographic photosensitive member according to claim 1, wherein a length a in a circumferential direction of the linear groove satisfies, with respect to 90% or more based on the entirety, a linear groove

A is more than or equal to 50 mu m and less than or equal to 400 mu m, and

Rzjis and Rsm of the support respectively satisfy

1.0 μm. ltoreq. Rzjis. ltoreq.1.5 μm, and

30μm≤Rsm≤40μm。

4. A process cartridge characterized in that it supports the electrophotographic photosensitive member according to any one of claims 1 to 3 and at least one unit selected from the group consisting of a charging unit, a developing unit, a transfer unit and a cleaning unit, and the process cartridge is detachably mountable to a main body of an electrophotographic apparatus.

5. An electrophotographic apparatus characterized by comprising the electrophotographic photosensitive member according to any one of claims 1 to 3, a charging unit, an exposing unit, a developing unit, and a transferring unit.

6. The electrophotographic apparatus according to claim 5, comprising, as a charging unit, a charging roller configured to abut against the electrophotographic photosensitive member and a charging unit that charges the electrophotographic photosensitive member by applying only a direct-current voltage.

Technical Field

The present invention relates to an electrophotographic photosensitive member, and a process cartridge and an electrophotographic apparatus including the electrophotographic photosensitive member.

Background

Electrophotographic apparatuses using an electrophotographic system are widely and commonly used as copiers, facsimile apparatuses, printers, and the like. In such an electrophotographic process, the surface of an electrophotographic photosensitive member provided with a photoconductive layer is uniformly charged, and is exposed with a laser, an LED, or the like according to image information to form an electrostatic latent image on the surface of the electrophotographic photosensitive member. Subsequently, according to the formed electrostatic latent image, toner is developed on the surface of the electrophotographic photosensitive member to form a toner image, and the toner image is transferred onto a recording material such as paper to form an image. Then, the residual toner on the electrophotographic photosensitive member that was not transferred is removed by the cleaner of the electrophotographic photosensitive member, and the following image forming process is repeated.

As an electrophotographic photosensitive member applicable to such an electrophotographic apparatus, an organic electrophotographic photosensitive member (OPC) using an organic photoconductive substance has been developed and becomes popular.

With the development of electrophotographic apparatuses, improvement in image quality is required, and therefore, shading unevenness caused by, for example, interference fringes on a halftone image due to interference with incident light and a streak-like unevenness portion (which was not a problem before) associated with a processing feed pitch of a support are sometimes considered to be a problem.

In order to solve such a problem, Japanese patent application laid-open No. 2002-311625 discloses a technique for reducing interference fringes by roughening the surface of a base body.

Disclosure of Invention

In general, the surface of the support is roughened to solve interference fringes on an image generated due to interference with light reflected from the support.

As a method for roughening the surface of the support body, for example, a method such as cutting or grinding is preferably used from the viewpoint of numerical control of the surface roughness of the support body and processing of the support body.

However, when the surface of the support is roughened by a method such as cutting and grinding, a linear-shaped groove (line-shaped groove) extending in the circumferential direction of the support is formed. The linear grooves are formed in correspondence with the processing feed pitch of the support body, and in some cases, stripe-shaped uneven portions due to the linear grooves are formed on the image.

Accordingly, an object of the present invention is to provide an electrophotographic photosensitive member capable of suppressing the generation of both interference fringes and striped unevenness.

The above object is achieved by the present invention described below.

In other words, the electrophotographic photosensitive member according to the present invention includes a cylindrical support, an undercoat layer, and a photosensitive layer in this order, wherein the surface of the support includes linear grooves along the circumferential direction of the support, and when a denotes the length of the linear grooves along the circumferential direction, the length a satisfies that the linear grooves are 90% or more based on the whole

50μm≤a≤500μm，

The ten-point average roughness Rzjis, the average length of the roughness curve elements Rsm and the skewness (degree of asymmetry) Rsk obtained from the roughness curve of the support surface in the axial direction according to JIS B0601:2001 satisfy

0.7μm≤Rzjis

Rsm is less than or equal to 50 μm, and

-4.0≤Rsk≤-0.2。

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, an electrophotographic photosensitive member capable of suppressing the generation of both interference fringes and striped unevenness can be provided.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

Drawings

Fig. 1 shows one example of an electrophotographic apparatus including a process cartridge having an electrophotographic photosensitive member of the present invention.

Fig. 2 shows one example of a centerless grinder for grinding the support of the electrophotographic photosensitive member of the present invention.

Fig. 3 shows one example of the layer constitution of the electrophotographic photosensitive member of the present invention.

Detailed Description

Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

In general, the surface roughness of the support is specified to eliminate interference fringes and streak-like unevenness on the image; however, it has been found that conventional regulations for roughness may not be sufficient to suppress interference fringes and streak-like unevenness on an image due to improvement in image quality.

In order to solve the technical problems occurring in the prior art described above, the present inventors have studied to adjust the length of the linear groove in the circumferential direction of the support body and also to adjust the roughness parameter in the axial direction of the support body.

As a result of the above-mentioned studies, it has been found that, when a represents the length of the linear grooves in the circumferential direction of the support, the length a satisfies 50 μm. ltoreq. a.ltoreq.500 μm with respect to the linear grooves of 90% or more based on the entirety, and the ten-point average roughness Rzjis, the average length Rsm of the roughness curve elements, and the skewness Rsk obtained from the roughness curve in the axial direction of the surface of the support according to JIS B0601:2001 satisfy 0.7 μm. ltoreq. Rzjis, Rsm. ltoreq.50 μm, and-4.0. ltoreq. Rsk. ltoreq.0.2, respectively, and as a result, the technical problems occurring in the prior art can be solved.

According to the present invention, the length a of the linear groove refers to the length of the groove in the circumferential direction of the support body due to the roughening of the support body. Rzjis, Rsm and Rsk are respectively represented by the following formulas.

Roughness of ten points

Zpi ═ the height from the highest curve peak height to the fifth highest curve peak height in the profile curve

Zvj height from lowest curve valley depth to fifth lowest curve valley depth in the profile curve

Average length of roughness curve elements

Length of contour curve element Xsi

Number of profile curve elements

Skewness (measure of asymmetry of probability density function along height)

Rq-root mean square height of roughness curve

l_rLength in the X-axis direction

Z (x) is the height in the Z-axis direction at position x

The reason why the problems can be solved by the above-described techniques will be described below.

The shorter the length of the linear groove in the circumferential direction, the lower the visibility on the image is caused, and therefore has a favorable effect on the suppression of interference fringes and streak-like unevenness. As Rz indicating the depth of the linear groove becomes higher, scattering of light reflected by the support body is facilitated, and as a result, suppression of interference fringes is facilitated. It is considered that as Rsm indicating the pitch of the linear grooves of the support becomes smaller, visibility on an image becomes lower, and as a result, interference fringes are favorably suppressed.

However, in some cases, the streak-like unevenness cannot be suppressed only by adjusting the above parameters. As a result of the investigation, it has been found that the streak-like unevenness can be suppressed by adjusting the skew (Rsk) in addition to the above-described roughness parameter.

Rsk is a roughness parameter indicating the degree of asymmetry, and when Rsk >0, the support has a large kurtosis (kurtosis), and when Rsk <0, the support has a shape having a small kurtosis.

It is considered that by adjusting the value of Rsk to-4.0. ltoreq. rsk.ltoreq.0.2, interference due to reflected light from the grooves formed on the support is weakened, and as a result, streaky uneven portions tend not to occur on the image.

As described above, these constitutions affect each other in a synergistic manner, and as a result, the effects of the present invention can be achieved.

In order to suppress the generation of streaky unevenness, the skewness (Rsk) is more preferably in the range of-1.2. ltoreq. Rsk. ltoreq-0.2.

For suppressing interference fringes, the above-mentioned parameters are more preferably in the ranges of 50 μm. ltoreq. a.ltoreq.400. mu.m, 1.0. mu.m. ltoreq. Rzjis. ltoreq.1.5. mu.m, and 30 μm. ltoreq. Rsm. ltoreq.40. mu.m.

[ electrophotographic photosensitive Member ]

The electrophotographic photosensitive member of the present invention includes a support, an undercoat layer, and a photosensitive layer in this order.

Examples of the production method of the electrophotographic photosensitive member of the present invention include a method of preparing a coating liquid for each layer described below, coating the coating liquid to achieve a desired layer order, and drying the coating liquid. In this case, examples of the method of coating the coating liquid include dip coating, spray coating, inkjet coating, roll coating, die coating, blade coating, curtain coating, wire bar coating, and loop coating. Among these, dip coating is preferable from the viewpoint of efficiency and productivity.

The layers will be described below.

< support >

In the present invention, the electrophotographic photosensitive member includes a support. In the present invention, the support preferably has a conductive support having conductivity. As the support body, a cylindrical support body is used. In order to adjust the roughness of the surface of the support body, the surface of the support body may be cut, ground, sandblasted, or the like.

As the material of the support, metal, resin, glass, or the like is preferable. Examples of metals include aluminum, iron, nickel, copper, gold, stainless steel, and alloys of these. Among them, a support made of aluminum is preferable.

The resin and the glass can be imparted with electrical conductivity by, for example, a treatment of mixing an electrically conductive material into the resin and the glass or covering the resin and the glass with an electrically conductive material.

< conductive layer >

In the present invention, a conductive layer may be provided on the support. By providing the conductive layer, defects or irregularities on the surface of the support can be hidden, or reflection of light on the surface of the support can be controlled. The conductive layer preferably contains conductive particles and a resin.

Examples of the material of the conductive particles include metal oxides, metals, and carbon black.

Examples of the metal oxide include zinc oxide, aluminum oxide, indium oxide, silicon oxide, zirconium oxide, tin oxide, titanium oxide, magnesium oxide, antimony oxide, and bismuth oxide. Examples of metals include aluminum, nickel, iron, nichrome, copper, zinc, and silver.

Among them, metal oxides are preferably used as the conductive particles, and particularly, titanium oxide, tin oxide, and zinc oxide are more preferably used.

When a metal oxide is used as the conductive particles, the surface of the metal oxide may be treated with, for example, a silane coupling agent, or the metal oxide may be doped with, for example, elemental phosphorus, elemental aluminum, or an oxide thereof.

The conductive particles may be a laminated configuration including core particles and a cover layer covering the core particles. Examples of the core particles include titanium oxide, barium sulfate, and zinc oxide. Examples of the capping layer include metal oxides such as tin oxide.

When a metal oxide is used as the conductive particles, the volume average particle diameter of the metal oxide is preferably 1nm or more and 500nm or less, more preferably 3nm or more and 400nm or less.

Examples of the resin include polyester resins, polycarbonate resins, polyvinyl acetal resins, acrylic resins, silicone resins, epoxy resins, melamine resins, polyurethane resins, phenol resins, and alkyd resins.

The conductive layer may further contain a masking agent such as silicone oil, resin particles, and titanium oxide.

The average film thickness of the conductive layer is preferably 1 μm or more and 50 μm or less, and particularly preferably 3 μm or more and 40 μm or less.

The conductive layer can be formed by preparing a coating liquid for the conductive layer containing the above-described respective materials and a solvent, forming a coating film from the coating liquid, and drying the coating film. Examples of the solvent used for the coating liquid include alcohol-based solvents, sulfoxide-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents. Examples of a method of dispersing the conductive particles in the coating liquid for the conductive layer include a method using a paint shaker, a sand mill, a ball mill, and a liquid impact type high-speed dispersing machine.

< undercoat layer >

In the present invention, an undercoat layer may be provided on the support or on the conductive layer. By providing the undercoat layer, the interlayer adhesion function is enhanced, and thus a charge injection preventing function can be imparted.

The primer layer preferably contains a resin. The undercoat layer may also be formed into a cured film by polymerizing a composition containing a monomer having a polymerizable functional group.

Examples of the resin include polyester resins, polycarbonate resins, polyvinyl acetal resins, acrylic resins, epoxy resins, melamine resins, polyurethane resins, phenol resins, polyvinyl phenol resins, alkyd resins, polyvinyl alcohol resins, polyethylene oxide resins, polypropylene oxide resins, polyamide acid resins, polyimide resins, polyamide-imide resins, and cellulose resins.

Examples of the polymerizable functional group possessed by the monomer having a polymerizable functional group include an isocyanate group, a blocked isocyanate group, a methylol group, an alkylated methylol group, an epoxy group, a metal alkoxide group, a hydroxyl group, an amino group, a carboxyl group, a thiol group, a carboxylic anhydride group, and a carbon-carbon double bond group.

In order to improve electrical properties, the undercoat layer may further contain an electron-transporting substance, a metal oxide, a metal, a conductive polymer, and the like. Among them, electron-transporting substances and metal oxides are preferably used.

Examples of the electron transporting substance include quinone compounds, imide compounds, benzimidazole compounds, cyclopentadienylene compounds, fluorenone compounds, xanthone compounds, benzophenone compounds, cyanovinyl compounds, halogenated aryl compounds, silole compounds, and boron-containing compounds. As the electron transporting substance, an electron transporting substance having a polymerizable functional group can be used to carry out copolymerization of the electron transporting substance and the above-mentioned monomer having a polymerizable functional group to form the undercoat layer into a cured film.

Examples of the metal oxide include indium tin oxide, indium oxide, titanium oxide, zinc oxide, aluminum oxide, and silicon dioxide. Examples of the metal include gold, silver, and aluminum.

The primer layer may further comprise an additive.

The average film thickness of the undercoat layer is preferably 0.1 μm or more and 50 μm or less, more preferably 0.2 μm or more and 40 μm or less, and particularly preferably 0.3 μm or more and 30 μm or less.

The undercoat layer can be formed by preparing a coating liquid for undercoat layer containing the above-mentioned respective materials and a solvent, forming a coating film from the coating liquid, and drying and/or curing the coating film. Examples of the solvent used for the coating liquid include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents.

< photosensitive layer >

The photosensitive layer of the electrophotographic photosensitive member is roughly classified into (1) a laminated type photosensitive layer and (2) a single layer type photosensitive layer. (1) The laminated photosensitive layer includes a charge generation layer containing a charge generation substance and a charge transport layer containing a charge transport substance. (2) The monolayer type photosensitive layer includes a photosensitive layer containing both a charge generating substance and a charge transporting substance.

(1) Laminated photosensitive layer

The stacked photosensitive layer includes a charge generation layer and a charge transport layer.

(1-1) Charge generating layer

The charge generation layer preferably contains a charge generation substance and a resin.

Examples of the charge generating substance include azo pigments, perylene pigments, polycyclic quinone pigments, indigo pigments, and phthalocyanine pigments. Among them, azo pigments and phthalocyanine pigments are preferable. Among the phthalocyanine pigments, oxytitanium phthalocyanine pigments, chlorogallium phthalocyanine pigments and hydroxygallium phthalocyanine pigments are preferable.

The content of the charge generating substance in the charge generating layer is preferably 40 mass% or more and 85 mass% or less, and more preferably 60 mass% or more and 80 mass% or less, based on the total mass of the charge generating layer.

Examples of the resin include polyester resins, polycarbonate resins, polyvinyl acetal resins, polyvinyl butyral resins, acrylic resins, silicone resins, epoxy resins, melamine resins, polyurethane resins, phenol resins, polyvinyl alcohol resins, cellulose resins, polystyrene resins, polyvinyl acetate resins, and polyvinyl chloride resins. Among them, a polyvinyl butyral resin is more preferable.

The charge generation layer may further include additives such as an antioxidant and an ultraviolet absorber. Specific examples of the additive include hindered phenol compounds, hindered amine compounds, sulfur compounds, phosphorus compounds, and benzophenone compounds.

The average film thickness of the charge generation layer is preferably 0.1 μm or more and 1 μm or less, and more preferably 0.15 μm or more and 0.4 μm or less.

The charge generating layer can be formed by preparing a coating liquid for the charge generating layer containing the above-described respective materials and a solvent, forming a coating film from the coating liquid, and drying the coating film. Examples of the solvent used for the coating liquid include alcohol-based solvents, sulfoxide-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents.

(1-2) Charge transport layer

The charge transport layer preferably contains a charge transport substance and a resin.

Examples of the charge transporting substance include polycyclic aromatic compounds, heterocyclic compounds, hydrazone compounds, styryl compounds, enamine compounds, biphenylamine compounds, triarylamine compounds, and resins having groups derived from these substances. Among them, triarylamine compounds and biphenylamine compounds are preferable.

The content of the charge transporting substance in the charge transporting layer is preferably 25 mass% or more and 70 mass% or less, more preferably 30 mass% or more and 55 mass% or less, based on the total mass of the charge transporting layer.

Examples of the resin include polyester resins, polycarbonate resins, acrylic resins, and polystyrene resins. Among them, polycarbonate resins and polyester resins are preferable. As the polyester resin, a polyarylate resin is particularly preferable.

The content ratio (mass ratio) of the charge transporting substance to the resin is preferably 4:10 to 20:10, more preferably 5:10 to 12: 10.

The charge transport layer may contain additives such as an antioxidant, an ultraviolet absorber, a plasticizer, a leveling agent, a slipping property imparting agent, and an abrasion resistance improving agent. Specific examples of the additives include hindered phenol compounds, hindered amine compounds, sulfur compounds, phosphorus compounds, benzophenone compounds, siloxane-modified resins, silicone oils, fluororesin particles, polystyrene resin particles, polyethylene resin particles, silica particles, alumina particles, and boron nitride particles.

The average film thickness of the charge transport layer is preferably 5 μm or more and 50 μm or less, more preferably 8 μm or more and 40 μm or less, and particularly preferably 10 μm or more and 30 μm or less.

The charge transporting layer can be formed by preparing a coating liquid for charge transporting layer containing the above-mentioned respective materials and a solvent, forming a coating film from the coating liquid, and drying the coating film. Examples of the solvent used for the coating liquid include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents. Among these solvents, ether solvents and aromatic hydrocarbon solvents are preferable.

(2) Single-layer type photosensitive layer

The monolayer type photosensitive layer can be formed by preparing a coating liquid for the photosensitive layer containing a charge generating substance, a charge transporting substance, a resin and a solvent, forming a coating film from the coating liquid, and drying the coating film. The charge generating substance, the charge transporting substance, and the resin are similar to those in the example shown in the above "(1) laminated photosensitive layer".

< protective layer >

in the present invention, a protective layer may be provided on the photosensitive layer. The provision of the protective layer can improve durability.

The protective layer preferably contains conductive particles and/or a charge transporting substance, and a resin.

Examples of the conductive particles include particles of metal oxides such as titanium oxide, zinc oxide, tin oxide, and indium oxide.

Examples of the charge transporting substance include polycyclic aromatic compounds, heterocyclic compounds, hydrazone compounds, styryl compounds, enamine compounds, biphenylamine compounds, triarylamine compounds, and resins having groups derived from these substances. Among them, triarylamine compounds and biphenylamine compounds are preferable.

Examples of the resin include polyester resins, acrylic resins, phenoxy resins, polycarbonate resins, polystyrene resins, phenol resins, melamine resins, and epoxy resins. Among them, polycarbonate resins, polyester resins and acrylic resins are preferable.

The protective layer may also be formed as a cured film by polymerizing a composition containing a monomer having a polymerizable functional group. Examples of the reaction in this case include thermal polymerization, photopolymerization, and radiation polymerization. Examples of the polymerizable functional group which the monomer having a polymerizable functional group has include an acryloyl group and a methacryloyl group. As the monomer having a polymerizable functional group, a material having an ability to transport charges may be used.

The protective layer may contain additives such as an antioxidant, an ultraviolet absorber, a plasticizer, a leveling agent, a sliding property imparting agent, and an abrasion resistance improving agent. Specific examples of the additives include hindered phenol compounds, hindered amine compounds, sulfur compounds, phosphorus compounds, benzophenone compounds, siloxane-modified resins, silicone oils, fluororesin particles, polystyrene resin particles, polyethylene resin particles, silica particles, alumina particles, and boron nitride particles.

The average film thickness of the protective layer is preferably 0.5 μm or more and 10 μm or less, and more preferably 1 μm or more and 7 μm or less.

The protective layer can be formed by preparing a coating liquid for the protective layer containing the above-described respective materials and a solvent, forming a coating film from the coating liquid, and drying and/or curing the coating film. Examples of the solvent used for the coating liquid include alcohol-based solvents, ketone-based solvents, ether-based solvents, sulfoxide-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents.

[ Process Cartridge and electrophotographic apparatus ]

The process cartridge of the present invention supports the above-described electrophotographic photosensitive member and at least one unit selected from the group consisting of a charging unit, a developing unit, a transfer unit, and a cleaning unit, and is detachably mountable to a main body of an electrophotographic apparatus.

An electrophotographic apparatus of the present invention includes the above-described electrophotographic photosensitive member, a charging unit, an exposure unit, a developing unit, and a transfer unit. Further, the electrophotographic apparatus of the present invention includes, as a charging unit, a charging roller configured to abut against the electrophotographic photosensitive member and a charging unit that charges the electrophotographic photosensitive member by applying only a direct-current voltage.

Fig. 1 shows one example of a schematic configuration regarding an electrophotographic apparatus including a process cartridge having an electrophotographic photosensitive member.

Reference numeral 1 denotes a cylindrical electrophotographic photosensitive member, which rotates around an axis 2 in the direction of an arrow at a predetermined peripheral speed. The surface of the electrophotographic photosensitive member 1 is charged by the charging unit 3 to have a predetermined positive potential or negative potential. Fig. 1 shows a roller charging manner by a roller-type charging member; however, a charging method such as a corona-type charging method, a proximity-type charging method, or an injection-type charging method may be employed. The surface of the charged electrophotographic photosensitive member 1 is irradiated with exposure light 4 from an exposure unit (not shown) to form an electrostatic latent image corresponding to the target image information. The electrostatic latent image formed on the surface of the electrophotographic photosensitive member 1 is developed with toner contained in the developing unit 5 to form a toner image on the surface of the electrophotographic photosensitive member 1. The toner image formed on the surface of the electrophotographic photosensitive member 1 is transferred onto a transfer material 7 by a transfer unit 6. The transfer material 7 on which the toner image is transferred is conveyed to a fixing unit 8, subjected to a fixing process of the toner image, and printed to the outside of the electrophotographic apparatus. In order to remove deposits such as toner remaining on the surface of the electrophotographic photosensitive member 1 after transfer, the electrophotographic apparatus may include a cleaning unit 9. The electrophotographic apparatus may not include a cleaning unit, that is, a cleanerless system that removes the above-described deposits by a developing unit or the like may be used. The electrophotographic apparatus may include a charge removing mechanism for performing charge removing processing on the surface of the electrophotographic photosensitive member 1 by the pre-exposure light 10 from a pre-exposure unit (not shown). In order to attach the process cartridge 11 of the present invention to the main body of the electrophotographic apparatus or detach the process cartridge 11 from the main body of the electrophotographic apparatus, a guide unit 12 such as a guide rail may be provided.

the electrophotographic photosensitive member of the present invention can be used for laser beam printers, LED printers, copiers, facsimile machines, multifunction complex machines of these, and the like.