JPH1165153A - Electrophotographic photoreceptor and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoreceptor with little deterioration in potential characteristics and no contamination in the base nor production of image defects such as moire and to stably obtain a sharp image of high density by forming an intermediate layer between a conductive base body and a photosensitive layer and incorporating resin-coated fine particles into the intermediate layer. SOLUTION: The intermediate layer of the photoreceptor contains fine particles coated with a resin. As fine particles coated with a resin, inorg. fine particles or org. fine particles coated with a resin coating film of 0.001 to 0.1 μm thickness are preferably used. If the resin coating is <0.001 μm thick, the effect of the resin coating is not obtd. so that when an image is formed by using coherent light, moire is produced. This is not desirable. If the resin coating is >0.1 μm thick, the surface of the intermediate layer is made too rough, which deteriorates the image quality during forming an image. The intermediate layer of the photoreceptor is formed between the conductive base body and the photosensitive layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member, and more particularly, to an electrophotographic photosensitive member in which an electrostatic latent image is formed by coherent light such as laser light or light emitting diode light, and an electrophotographic photosensitive member. The present invention relates to an image forming apparatus to be used.

[0002]

2. Description of the Related Art Generally, in an electrophotographic photoreceptor (hereinafter, also simply referred to as a photoreceptor) repeatedly used for image formation, unnecessary charge injection is prevented to maintain good chargeability, and In order to improve the adhesion between the conductive substrate and the photosensitive layer, an intermediate layer using a resin having a relatively low resistance is provided between the conductive substrate and the photosensitive layer.

On the other hand, as the above-mentioned photoreceptor, there are an inorganic photoreceptor having a photosensitive layer containing an inorganic photoconductive substance and an organic photoreceptor having a photosensitive layer containing an organic photoconductive substance. Organic photoreceptors that are less toxic than their bodies, are low in cost, have excellent processability, and have a high degree of freedom for selection according to the purpose have been developed and put into practical use.

It is important for the organic photoreceptor to have a photosensitive layer having a function separated into a charge generating function and a charge transporting function. Usually, the organic photoreceptor has a charge generating layer and a charge transporting function via an intermediate layer on a conductive substrate. A stacked organic photoreceptor in which layers are provided in layers is used.

However, in the above-mentioned laminated organic photoreceptor, light for image exposure causes multiple reflections between the surface of the conductive substrate and the surface layer of the photoreceptor, and the reflected lights interfere with each other to generate moire. Image quality during image formation is reduced.

Therefore, a technique for preventing the above-described moiré by providing irregularities on the surface of the intermediate layer provided on the conductive substrate has been proposed in, for example, Japanese Utility Model Application Laid-Open No. 60-189747 or Japanese Utility Model Application Laid-Open No. 60-247647. Have been.

[0007]

However, simply providing the surface of the intermediate layer with irregularities usually results in the refractive index of the material of the intermediate layer and the charge generation layer and / or the charge transport layer in the laminated photoreceptor. Since the refractive index of the material is very close to the above, there is almost no interface between the layers in the optical sense, and it is almost useless to prevent moire. Further, if the surface of the intermediate layer is made more uneven than necessary, it adversely affects the photosensitive layer applied thereon and degrades the image quality (for example, in the case of the reversal development method, it appears as a stain on the background, In the ordinary developing method, the black solid portion is poorly buried and density unevenness is likely to occur).

On the other hand, it has been proposed to add a pigment or the like to the intermediate layer in order to make the surface of the intermediate layer uneven.
Generally, the incident light is less scattered by the pigment, and is hardly used to prevent moire.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and has as its object to prevent potential characteristics from deteriorating in the process of repeatedly forming an image using coherent light.
An object of the present invention is to provide a photoreceptor capable of stably obtaining a high-density and clear image without occurrence of image defects such as background stains and moire.

[0010]

The above object is achieved by the following constitution.

1. An electrophotographic photosensitive member having an intermediate layer between a conductive substrate and a photosensitive layer, wherein the intermediate layer contains fine particles coated with a resin.

2. 2. The electrophotographic photoconductor according to the above item 1, wherein the fine particles are inorganic fine particles.

3. 2. The electrophotographic photoconductor according to the above item 1, wherein the fine particles are organic fine particles.

4. Wherein the resin coated on the fine particles is different from the binder resin of the intermediate layer.
4. The electrophotographic photoreceptor according to any one of claims 1 to 3.

[0015] 5. An image forming apparatus using the electrophotographic photosensitive member according to any one of the above items 1 to 4.

Hereinafter, the present invention will be described in detail.

The photoreceptor of the present invention is characterized in that the intermediate layer contains fine particles coated with a resin, and the fine particles coated with the resin preferably contain 0.001 A resin coating with a thickness of about 0.1 μm is used. 0.001 resin coating thickness
When the thickness is less than μm, the effect of resin coating is not obtained, and moire occurs when an image is formed using coherent light. On the other hand, if the thickness of the resin coating exceeds 0.1 μm, the unevenness on the surface of the intermediate layer becomes excessively large, deteriorating the image quality during image formation. The intermediate layer of the photoreceptor of the present invention is provided between the conductive substrate and the photosensitive layer.

<Inorganic fine particles>
For example, alumina (Al ₂ O ₃ ), silica (SiO ₂ ), titanium oxide (TiO ₂ ), zinc oxide (ZnO), cerium oxide (CeO ₂ ), ferric oxide (Fe ₂ O ₃ ), zinc sulfide (ZnS) ), Potassium iodide (KI), magnesium oxide (MgO), cadmium sulfide (CdS), copper sulfate, magnesium chloride, sodium carbonate, magnesium sulfate,
Powders such as potassium chloride, calcium chloride, sodium chloride, silver chloride, nickel sulfate, ammonium thiocyanate, etc., and asbestin (Ca
-Mg-Silicalate), clay, kaolin,
Clay - acid clay - disilazide (aluminum silicate), diatomaceous earth, chalk (CaCO _3), gypsum (CaSO ₄ · 2H
₂ O), talc-talc powder (3MgO.4SiO ₂ .H)
₂ O), barite (BaSO ₄ ), mica powder (Al ₂ O _3.
White pigments such as K ₂ O.SiO ₂ ), antimony white (Sb ₂ O ₃ ), lithopone-orzinc white (ZnS + BaS)
O ₄ ), black pigments such as carbon black, gas black,
Iron black, black iron oxide, graphite, graphite, manganese dioxide, chromium black, red pigments such as red iron oxide, red iron oxide, iron red, toluidine red, etc., yellow pigments such as titanium yellow, ocher, ocher, and green pigments Chromium oxide, cobalt chrome green, and blue pigments include ultramarine, ultramarine, and cobalt blue, and purple pigments include purple iron oxide and mars purple, as well as Al powder, stainless steel powder, and glass frit.

<Organic fine particles>
For example, polyvinylidene fluoride, polyvinylidene chloride,
Resin fine particles such as Teflon, polyacrylonitrile, polystyrene, polymethyl methacrylate, and polyvinyl butyral are exemplified.

Further, for example, organic pigment fine particles of azo type, triphenylmethane type, quinoline type, anthraquinone type, phthalocyanine type and the like can be mentioned.

Among the above-mentioned inorganic and organic fine particles, workability,
From the viewpoints of dispersibility in the intermediate layer, moiré prevention effect, etc., fine particles of inorganic oxides having a sphericity of preferably 0.5 or more, more preferably 0.8 or more, or fine particles of a fluorine atom or a silicon atom-containing resin are excellent. In particular, fine particles of the inorganic oxide are preferable.

Here, the sphericity refers to the ratio of the diameter of the smallest circumscribed circle to the diameter of the largest inscribed circle of the fine particles, and 1.0 when the inscribed circle and the circumscribed circle match. .

The volume average particle diameter of the inorganic and organic fine particles is preferably 0.1 to 5 μm, more preferably 0.1 to 5 μm.
When the thickness is less than 0.1 μm, the effect of preventing moiré is insufficient, and when the thickness exceeds 5 μm, the unevenness of the intermediate layer becomes excessively large, and the image quality is deteriorated.
Black spots easily occur.

The volume average particle size of the above-mentioned inorganic and organic fine particles (substantially the same as the volume average particle size when the fine particles are coated with a resin) is measured by a laser diffraction type particle size distribution analyzer “HEROS” (Sympatech). (Manufactured by K.K.).

<Resin Coating on Fine Particles> As the resin forming the coating layer of the inorganic and organic fine particles, a resin having excellent affinity and dispersibility with the binder resin of the intermediate layer is selected. From the viewpoint of the moiré prevention effect, those having optical characteristics different from the binder resin of the intermediate layer are preferable. Preferred resins for coating the fine particles include, for example, polyamide resin “CM-8000” (manufactured by Toray Industries, Inc.), silicone resin “KR-5240” (manufactured by Shin-Etsu Chemical Co., Ltd.), and polyamide resin Resin “Lacamide 521
6 "(manufactured by DIC Corporation) or polystyrene resin" High Flow 55 "(manufactured by Mitsubishi Monsanto Co., Ltd.).

Examples of the resin coating method for the inorganic and organic fine particles include, for example, an interfacial polymerization method, an in situ polymerization method, a hardening coating method in liquid, a coacervation method (aqueous / organic solution), a wurster method, and a spray method. There are various methods such as a dry method, and it is preferable to select according to the type of resin to be coated.

The addition amount of the resin-coated fine particles to the intermediate layer is determined based on the binder resin of the intermediate layer.
Preferably 0.5 to 30 wt%, more preferably 2-1.
When the content is less than 0.5 wt%, the effect of preventing moiré is insufficient, and when it exceeds 30 wt%, the image quality is deteriorated.

Hereinafter, the present invention will be described in more detail.

<Structure of Photoreceptor> The photoreceptor of the present invention is provided with an intermediate layer containing the above-mentioned resin-coated inorganic or organic fine particles on a conductive substrate, and preferably an organic photosensitive layer, particularly preferably, on the intermediate layer. Can be obtained by providing a function-separated type photosensitive layer having a charge generation layer and a charge transport layer.

As the conductive substrate, a metal substrate such as aluminum, nickel or stainless steel, a plastic substrate in which a conductive pigment such as carbon is dispersed, or a metal deposited on an insulating support (such as plastic or plastic film). Examples thereof include a substrate and a substrate coated with a conductive paint.

The intermediate layer provided on the conductive substrate contains inorganic or organic fine particles coated with a resin as described above, and the thickness of the intermediate layer is preferably 0.1 to 15 μm.
m, more preferably 0.3 to 10 μm, and 0.1 μm
If it is less than m, the function as an intermediate layer (image quality adjustment, moiré prevention and adhesiveness) cannot be achieved, and if it exceeds 15 μm, poor adhesion tends to occur, fogging tends to occur, and image quality tends to deteriorate.

Examples of the binder resin for forming the intermediate layer include polyvinyl alcohol, polyvinyl butyral, cellulose resin, polyamide resin, carboxymethyl cellulose, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-maleic acid copolymer And a resin having a relatively low electric resistance such as casein.

The intermediate layer may further include a surfactant, if necessary, for improving coating processability or conductivity.
A conductive agent, a conductive fine powder or the like may be added.

In a photoreceptor having a function-separated type photosensitive layer obtained by laminating the charge generation layer and the charge transport layer,
The charge generation layer is formed by dispersing a charge generation material (CGM) in a binder resin as needed. As CGM, azo compounds such as metal or metal-free phthalocyanine compounds, bisazo compounds, and trisazo compounds, squarium compounds, azurenium compounds, perylene compounds,
Examples include, but are not limited to, indico compounds, quinacridone compounds, polycyclic quinone compounds, cyanine dyes, xanthene dyes, charge transfer complexes composed of poly-N-vinylcarbazole, trinitrofluorenone, and the like. These may be used as a mixture of two or more as necessary.

However, in order to achieve the object of the present invention at the highest level, a kind of perylene compound, imidazole perylene compound or metal phthalocyanine compound such as titanyl phthalocyanine (TiOPc), gallium phthalocyanine (GaPc) or hydroxygallium phthalocyanine (GaOHPc Is preferred.

Examples of the binder resin usable for the charge generation layer include polystyrene resin, polyethylene resin, polypropylene resin, polyacrylic resin, polymethacrylic resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinyl butyral resin, and poly (vinyl butyral) resin. Epoxy resins, polyurethane resins, polyphenol resins, polyester resins, polyalkyd resins, polycarbonate resins, polysilicone resins, polymelamine resins, and copolymer resins containing two or more of the repeating units of these resins,
Examples include, but are not limited to, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, and high molecular organic semiconductors such as poly-N-vinyl carbazole. Absent.

Among the above, when an imidazole perylene compound is used as CGM, a preferred binder resin is polyvinyl butyral resin, and CGM is TiO.
As a preferred binder resin when Pc is used, a polysilicone resin or a polyvinyl butyral resin, or a mixture of both is used. The thickness of the charge generation layer is preferably 0.01 to 2 μm.

Next, the charge transport layer is composed of a charge transport material (CTM) alone or together with a binder resin. Examples of the CTM include carbazole derivatives, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, and oxazolone. Derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives,
Phenamine derivatives, aminostilbene derivatives, triazoleamine derivatives, phenylenediamine derivatives, stilbene derivatives, benzidine derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, and the like, but are not limited thereto. Not necessarily. These may be used alone or in combination of two or more.

As the binder resin usable for the charge transport layer, for example, polycarbonate resin, polyacrylate resin, polyester resin, polystyrene resin, styrene-acrylonitrile copolymer resin, polymethacrylate resin, styrene-methacrylic resin Examples include acid ester copolymer resins, but are not limited thereto. Also, in order to reduce fatigue deterioration when repeatedly used or to improve durability,
Any known antioxidant, electron-accepting substance, surface modifier, plasticizer, environment-dependent reducing agent, etc. can be added to any of the layers of the photoreceptor, if necessary, in an appropriate amount.
The thickness of the charge transport layer is preferably 5 to 50 μm.
It is.

If necessary, a protective layer may be provided on the photosensitive layer of the laminated organic photoreceptor obtained as described above.
The protective layer may contain a charge transport material (CTM), and additives such as a dye for correcting color sensitivity and an antioxidant may be added.

<Structure of Image Forming Apparatus> FIG. 1 is a cross-sectional view showing an example of an image forming apparatus for forming an image using the photoreceptor of the present invention, wherein 1 is modulated by, for example, a digital signal from a computer. This is image exposure of coherent light such as laser light or light-emitting diode light, and the image exposure forms an electrostatic latent image on the photoreceptor 7 of the present invention, which has been uniformly charged in advance by the charger 6. The electrostatic latent image is developed by a reversal developing method under application of a bias from a bias power supply 8 to form a toner image in a contact or non-contact manner by a developing device 2, and a toner image is formed on the photoconductor 7. Is transferred by the action of the transfer pole 3 onto the transfer paper 4 conveyed in synchronization with the image formation of
Thereafter, through a separation and fixing process, a fixed image is obtained on the transfer paper 4. On the other hand, the photoconductor 7 after the transfer is cleaned of residual toner by a cleaning device 5 having a cleaning blade, and is prepared for the next image formation.

[0042]

In the photoreceptor of the present invention, when producing the photoreceptor, an intermediate layer containing dispersed inorganic or organic fine particles coated with a resin is provided on a conductive substrate, and the photosensitive layer is coated on the intermediate layer. However, due to the presence of the intermediate layer, the coating processability of the photosensitive layer is excellent, and when image formation is repeatedly performed using coherent light such as laser light as image exposure, No deterioration and no stain on the background
It also has excellent effects such as no moiré.

Although the reason for the above effects is not necessarily clear, since the resin-coated inorganic or organic fine particles are dispersed and contained very uniformly in the intermediate layer, a uniform photosensitive layer is formed thereon. Also, even when image exposure of coherent light is performed on the photoreceptor, the image exposed light is scattered in the intermediate layer having resin-coated fine particles in a complicated manner, and it is presumed that moire is eliminated. .

In the above description, it is assumed that the effect of preventing moiré is greater when the binder resin of the intermediate layer and the resin coated with the fine particles are resins having different optical characteristics.

[0045]

The present invention will be specifically described below with reference to examples.

<Preparation of Fine Particle 1 (with Resin Coating)> A solution of polyamide resin “CM-8000” (manufactured by Toray Industries, Inc.) in methanol and fine alumina particles were sprayed and dried in a spray drying apparatus. Fine particles 1 (with resin coating) having a sphericity of 0.9, a resin coating layer thickness of 0.01 μm, and a volume average particle diameter of 0.8 μm were obtained.

<Preparation of fine particles 2 to 8 (with resin coating)>
Fine particles (with resin coating) 2 to 8 were obtained by changing the coating resin of the fine particles 1, the solvent, the material of the fine particles, the sphericity, the resin coating layer thickness, and the volume average particle diameter of the fine particles as shown in Table 1.

[0048]

[Table 1]

In the table, as the coating resin other than the polyamide resin, a polyurethane resin “PARAPRENE 22” was used.
S "(manufactured by Hodogaya Chemical Co., Ltd.), silicone resin" KR-5240 "(manufactured by Shin-Etsu Chemical Co., Ltd.), and styrene resin" High Flow 55 "(manufactured by Mitsubishi Monsanto Co., Ltd.). .

<Preparation of Photoconductor 1> A mirror-finished aluminum drum base having a diameter of 60 mm and a height of 273 mm was used as a conductive support, and the following intermediate layer coating solution composition UCL-1 was formed on the drum base. Was applied and dried so as to have a dry film thickness of 1.0 μm to form an intermediate layer.

<< Intermediate Layer Coating Composition UCL-1 >> Ethylene-vinyl acetate copolymer “ELVAX 4260” (manufactured by Mitsui DuPont Chemical Co., Ltd.) 50 g toluene / n-butanol = 5/1 (vol ratio) 2000 ml) In addition to the above components, fine particles 1 are further added so as to be 15 wt% of the binder resin of the intermediate layer.

<< Charge Generating Layer Coating Composition CGL-1 >> Y-type titanyl phthalocyanine (CGM-1) having the following structure 100 g Silicone resin "KR-5240" (manufactured by Shin-Etsu Chemical Co., Ltd.) 100 g t-butyl acetate 10,000 ml A coating solution obtained by dispersing the above composition using a sand mill for 17 hours was coated on the above intermediate layer and dried to form a 0.5 μm thick charge generation layer.

[0053]

Embedded image

In the X-ray diffraction spectrum with respect to Cu-Kα ray, the above-mentioned CGM-1 has a Bragg angle 2θ of 9.5 ± 0.2 °, 24.1 ± 0.2 °, 27.2 ± 2 °.
Y-type titanyl phthalocyanine in a crystalline state showing a peak at 0.2 °.

The following charge transport layer coating solution composition CTL-1 was coated on the above-mentioned charge generation layer and dried to form a charge transport layer having a thickness of 23 μm. Thus, Photoreceptor 1 of the present invention was obtained.

<< Charge Transport Layer Coating Solution Composition CTL-1 >> Charge Transport Material (CTM-1) having the following structure 500 g Polycarbonate “Z-200” (manufactured by Mitsubishi Gas Chemical Company, Inc.) 560 g Ethylene chloride 2800 ml Silicone oil KF-54 (Shin-Etsu Chemical Co., Ltd.) 100 ppm based on the total solids in the charge transport layer

[0057]

Embedded image

<Preparation of Photoconductors 2 to 9> Fine particles 2 to 8 (with resin coating) and fine particles 9 (without resin coating) are used instead of fine particles 1 (with resin coating) in the intermediate layer of photoconductor 1, and Photoconductors 2 to 8 of the present invention and Photoconductor 9 of Comparative Example were obtained in the same manner as Photoconductor 1 except that the content of the fine particles with respect to the binder resin in the intermediate layer was changed as shown in Table 2.

<Preparation of Photoconductor 10> A mirror-finished aluminum drum base having a diameter of 60 mm and a height of 273 mm was used as a conductive support.

The following intermediate layer coating solution composition UCL-2 was applied on the drum substrate and dried to a dry film thickness of 1.0 μm to form an intermediate layer.

<< Interlayer Coating Composition UCL-2 >> Copolymerized Nylon Resin (CM-8000) (manufactured by Toray Industries, Inc.) 2 g Methanol / n-butanol = 10/1 (vol ratio) 1000 ml Further, fine particles 1 are added so as to be 15 wt% of the binder resin of the intermediate layer.

<< Charge Generating Layer Coating Composition CGL-2 >> Y-type titanyl phthalocyanine (CGM-1) 100 g Silicone resin “KR-5240” (manufactured by Shin-Etsu Chemical Co., Ltd.) 100 g t-butyl acetate 10,000 ml Was dispersed in a sand mill for 17 hours, and the coating liquid obtained was applied on the intermediate layer and dried to form a charge generation layer having a thickness of 0.5 μm.

The following charge transport layer coating solution composition CTL-2 was applied onto the above-mentioned charge generation layer so as to have a dry film thickness of 23 μm and dried to obtain a photoreceptor 10 of the present invention.

<< Charge Transport Layer Coating Composition CTL-2 >> Charge transport substance (CTM-2) having the following structure: 500 g Polycarbonate “Z-200” (manufactured by Mitsubishi Gas Chemical Co., Ltd.) 560 g Ethylene chloride 2800 ml Silicone oil KF-54 (Shin-Etsu Chemical Co., Ltd.) 100 ppm based on the total solids in the charge transport layer

[0065]

Embedded image

<Preparation of Photoconductors 11 to 14> In place of the fine particles 1 (with resin coating) in the intermediate layer of the photoconductor 10, fine particles 2 were used.
3 (with resin coating) and fine particles 9 and 10 (without resin coating), and the same method as in the photoreceptor 10 except that the content of the fine particles with respect to the binder resin in the intermediate layer was changed as shown in Table 2. 11 and 12 and Comparative Photoconductor 1
3, 14 were obtained.

[0067]

[Table 2]

<Evaluation of electrophotographic performance> The above photoreceptors 1 to 14
Were sequentially mounted on a laser printer “LP-3015” (manufactured by Konica Corporation) using a laser beam of λ = 780 nm, and a potential characteristic test and an image test were performed at 20 ° C. and 50% RH atmosphere. The results are shown in Table 3.

<< Evaluation of Potential Characteristics >>
The fluctuation value (absolute value) ΔL and the unexposed portion of the potential of the exposed portion from the initial stage when rotating 1000 times while performing charging and intermittent exposure of laser light, respectively, are sequentially mounted on the laser printer in which an electrometer is arranged in the developing portion. The fluctuation value (absolute value) ΔH of the potential was measured, and the results are shown in Table 3.

<< Evaluation of Image >> The photoreceptors 1 to 14 were sequentially mounted on the laser printer, and moire in a halftone area and background stains were printed 1000 times using a document having a halftone image. The presence or absence of occurrence was visually observed, and the results were evaluated according to the following evaluation criteria in a “O” or “X” system. The results are shown in Table 3.

<< Evaluation Criteria >> ：: Not observed at all △: Thin moire is observed at the end, but there is no problem in practical use.

Δ: Light moiré is observed in the halftone area. X: Clear moiré is observed in the halftone area, and background stain is observed in the unexposed area.

[0073]

[Table 3]

As is apparent from Table 3, according to the photoreceptor of the present invention and the image forming apparatus using the photoreceptor, when the image is repeatedly exposed by coherent light such as laser light to form an image, The variation in potential of the unexposed area and the unexposed area is very small, and a high-quality image free of image defects such as moiré and stain on the background can be obtained. In addition, it can be seen that image defects such as moiré and stain on the background occur, and a high-quality image cannot be obtained.

[0075]

As demonstrated in the examples, according to the photoreceptor of the present invention and the image forming apparatus using the photoreceptor, in the process of repeatedly forming an image using coherent light such as laser light, It has excellent effects such as no deterioration of the potential characteristics of the photoreceptor, no occurrence of image defects such as moiré and stains on the background, and a stable high-density image can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an image forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image exposure 2 Developing device 3 Transfer pole 4 Transfer paper 5 Cleaning device 6 Band electrode 7 Photoconductor 8 Bias power supply

Claims (5)

[Claims] 1. An electrophotographic photosensitive member having an intermediate layer between a conductive substrate and a photosensitive layer, wherein the intermediate layer contains resin-coated fine particles. 2. The electrophotographic photosensitive member according to claim 1, wherein said fine particles are inorganic fine particles. 3. The electrophotographic photosensitive member according to claim 1, wherein the fine particles are organic fine particles. 4. The resin coated on the fine particles is different from the binder resin of the intermediate layer.
4. The electrophotographic photoreceptor according to any one of claims 1 to 3. 5. An image forming apparatus using the electrophotographic photoreceptor according to claim 1.