JPH11272002A - Eletrophotographic photoreceptor and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a photoreceptor which causes no microscopic fluctuations of the resistance of a photoreceptor and which enables formation of a good image without failure by forming a layer containing at least an amorphous metal oxide conducting agent on a conductive base body. SOLUTION: This photoreceptor has a layer containing at least an amorphous metal oxide conducting agent on a conductive base body. As for the conducting agent, a colloidal metal oxide sol is used. This sol is amorphous and has a broad scattering region with >=5 halfwidth having the peak between 20 deg. and 70 deg. of Bragg angle 2θmeasured by X-ray diffraction method using CUKα ray. As for the conductive base body, for example, a material having <=1×10<8> Ω.cm volume resistivity is used. As for the metal oxide, ZnO, TiO2 , SnO2 or the like is preferably used. As for the production method, any methods of dispersing metal oxide superfine particles in a proper solvent or of decomposing a solvent- soluble metal compd. in a solvent can be used.

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 used for image formation such as a copying machine, a printer or a facsimile.

[0002]

2. Description of the Related Art At present, most of high-quality and high-speed image forming apparatuses are based on an electrophotographic system, and among them, photoconductor technology is one of the key points. I have.

An electrophotographic photoreceptor is manufactured by forming an optical semiconductor layer (photosensitive layer) on a substrate having good conductivity. Recently, an intermediate layer (undercoat layer) is provided between the two layers. Has become widely practiced. The purpose is
Although there are various types such as so-called black spot failure prevention, it is a major problem how to provide appropriate conductivity to these layers.

For example, Japanese Patent Laid-Open Publication No. Sho 59-59 discloses a technique in which tin oxide particles are contained in a conductive intermediate layer together with titanium oxide particles.
84257. This technology has good conductivity, but poor dispersibility and the surface of the conductive intermediate layer becomes rough,
The surface of the conductive intermediate layer is smoothened by containing titanium oxide particles having good dispersibility together with tin oxide, which easily causes image defects.

In Japanese Patent Application Laid-Open No. 61-36755, the particle size is 0.5
A technique in which particles having a particle size of at least μm and particles having a particle size of less than 0.5 μm are contained in a conductive intermediate layer is disclosed. When light passing through the organic photosensitive layer is specularly reflected on the surface of the substrate, interference occurs with the incident light, and moire fringes occur. Therefore, by incorporating two types of particles having different particle diameters into the conductive intermediate layer, the reflected light is scattered, and interference with incident light is made less likely to occur.

[0006]

On the other hand, in order to make the conductivity of the conductive intermediate layer uniform, attempts have been made to reduce the particle size of the conductive agent. However, according to the study of the present inventors, when the particle size of the powdered conductive agent is reduced, the surface energy increases, and the powder is easily aggregated. The conductive layer containing the aggregated conductive agent partially increases conductivity, and causes a charge leakage in this portion. The leaked portion of the charged charges causes image defects such as so-called white spots and black spots.

That is, the aggregation of the conductive agent causes a variation in the microscopic resistance value in the photoconductor. The variation in the micro-resistance value is linked to the variation in the electric charge applied to the photoconductor, and causes the toner image to be uneven in the highlight image. In particular, the present inventors have found that this problem becomes remarkable when the toner is reduced in particle size to improve the image quality.

As disclosed in the prior art, when titanium oxide or barium sulfate fine particles are added for the purpose of improving the dispersibility of a conductive agent, a transparent substrate photoreceptor is used.
In a photoconductor for internal exposure of a transparent substrate used for exposure from the inside of the photoconductor, the exposure light is scattered by the added fine particles, making it difficult to reproduce a high-definition image.

It is an object of the present invention to provide a method for imparting appropriate conductivity to an intermediate layer (undercoat layer) between the surface of a substrate of an electrophotographic photosensitive member and a photosensitive layer. It does not cause variation in the microscopic resistance value of the photoreceptor, is excellent in transparency, has little variation in transparency, and can be applied to an image forming method in which a photoreceptor having a transparent substrate is exposed from the inside. An object of the present invention is to provide an electrophotographic photoreceptor to which a method for imparting conductivity that enables good exposure is applied and a method for producing the same.

[0010]

Means for Solving the Problems The present inventors have found that the conductive agent has a small particle size and good dispersibility, does not cause variations in the microscopic resistance value of the photosensitive member, and does not cause a failure. As a result of intensive studies to provide a method capable of forming an image, the present invention has been accomplished.

The object of the present invention is achieved by adopting the following constitution.

[1] An electrophotographic photosensitive member having a layer containing at least an amorphous metal oxide conductive agent on a conductive substrate.

[2] A photosensitive layer is provided on a conductive substrate, and a conductive intermediate layer is provided between the photosensitive layer and the conductive substrate. The conductive intermediate layer contains the conductive agent. [1] The electrophotographic photosensitive member according to [1].

[3] The conductive agent has a diameter of 1 to 100 nm.
[1] or [2].
The electrophotographic photosensitive member according to the above.

[4] The electrophotographic photosensitive member according to [1], [2] or [3], wherein the conductive agent is amorphous tin oxide.

[5] An electrophotographic photoreceptor having at least a conductive intermediate layer on a conductive substrate, wherein the conductive intermediate layer contains a colloidal metal oxide sol as a conductive agent. Photoreceptor.

[6] The electrophotographic photosensitive member according to [5], wherein the conductive agent is colloidal tin oxide.

[7] In a method for producing an electrophotographic photosensitive member having at least a conductive intermediate layer on a conductive substrate,
A method for producing an electrophotographic photosensitive member, comprising adding a colloidal metal oxide sol as a conductive agent to the conductive intermediate layer.

[8] The method for producing an electrophotographic photosensitive member according to [7], wherein the conductive agent is a colloidal tin oxide sol.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, 1 to 100 n
Since the dispersion state of particles having a diameter of m is stable, this size is referred to as a colloid dimension. Particles having a size of the colloid dimension are regarded as colloid particles, and the state in which the colloid particles are dispersed is referred to as a colloid in the present invention. Say a state.

The present invention is characterized in that a colloidal metal oxide sol is employed as the conductive agent.

The colloidal metal oxide sol of the present invention is characterized by being amorphous. The term “amorphous” as used herein refers to a Bragg angle of 2θ by X-ray diffraction using CuKα radiation.
It has a broad scattering band with a half value width of 5 or more having a peak at 20 ° or more and 70 ° or less, and a 2θ value of 70 or more.
° or more crystalline diffraction lines. In this case, the strongest intensity among the crystalline diffraction lines preferably observed at a 2θ value of 70 ° or more has the highest diffraction line intensity at the apex of a broad scattering band observed at a 2θ value of 20 ° or more and 70 ° or less. 50
It is preferably 0 times or less, more preferably 10 times or less.
It is 0 or less.

The conductivity of the conductive agent is such that its volume resistivity is 1 ×
Use a material having a resistance of 10 ⁸ Ω · cm or less, preferably 1 ×
It is 10 ⁵ Ω · cm or less.

The measurement of conductivity is performed as follows.
By applying a pressure of 100 kg / cm ^{2 to} the sample, a disc-shaped pellet having a diameter of 4 cm and a thickness of 0.2 cm is formed. The resistance (Ω · cm) of this pellet is
P (Mitsubishi Yuka) was used for the measurement.

Since the conductive agent of the present invention is in a colloidal state at the time of production, it is naturally dried to a powder, and the powder sample is subjected to X-ray diffraction and conductivity measurement.

In the present invention, the metal oxide is not limited to, but is preferably, for example, ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , Si
O ₂ , MgO, BaO, MoO ₃ , V ₂ O _{5 and the} like can be mentioned. Among these, ZnO, TiO ₂ and SnO ₂ are particularly preferred, and the most preferred is a colloid of SnO ₂ (tin oxide).

The method for producing a colloidal metal oxide sol according to the present invention is a method for producing by dispersing ultra-fine particles of a metal oxide (for example, tin oxide) in a suitable solvent, and a method for dissolving a metal compound soluble in a solvent in a solvent. Any method such as a method of producing from a decomposition reaction in the above can be adopted.

When the compatibility of the solvent of the metal oxide dispersion at the time of production with the protective colloid binder is poor, the solvent is replaced with a solvent suitable for dispersing in the binder. Or a compound capable of stably dispersing the metal oxide sol is added as appropriate, and the metal oxide ultrafine particles are dried and separated together with the compound added by heating to 300 ° C. or lower, preferably 200 ° C. or lower, further 150 ° C. or lower. And redispersed in water or water mixed with another solvent.

The tin compound used in the method for producing from the decomposition reaction of a tin compound soluble in a solvent in a solvent includes a compound containing an oxo anion such as K ₂ SnO ₃ .3H ₂ O, and a compound such as SnCl ₄ . water-soluble halide, R _'2 S
having the structure of nR ₂ , R ₃ SnX, R ₂ SnX ₂ (C
H ₃ ) ₃ SnCl. (Pyridine), (C ₄ H ₉ ) ₂ Sn (O
CC ₂ H ₅₎ organometallic compounds such as _{2, Sn (SO 4) 2} · 2
Oxo salts such as H ₂ O can be mentioned.

After dissolving a tin compound soluble in these solvents in the solvent, a tin oxide sol is produced by a physical method such as heating and pressurizing, or a chemical method such as oxidation, reduction and hydrolysis. Alternatively, a tin oxide sol is produced via an intermediate.
For example, Japanese Patent Publication No. 35-6616 discloses that SnCl ₄
Dissolve in 00 volumes of distilled water to precipitate stannic hydroxide, then add aqueous ammonia to make it slightly alkaline, dissolve the precipitate, and heat until ammonia odor disappears to produce colloidal tin oxide sol. A method is described.

Examples of the solvent include, in addition to water, alcohol solvents such as methanol, ethanol, and isopropanol; ether solvents such as tetrahydrofuran, dioxane and diethyl ether; aliphatic organic solvents such as hexane and heptane;
Various solvents can be used depending on the tin compound such as an aromatic organic solvent such as benzene and pyridine, and water and alcohols are preferable.

According to this method, it is possible to add a compound containing an element other than a tin compound soluble in a solvent during the production, for example, a fluorine-containing compound or a metal capable of taking a trivalent or pentavalent coordination number. Compounds can be introduced.

As the fluorine-containing compound soluble in a solvent,
Either ionic fluoride or covalent fluoride may be used, and metal fluorides such as K ₂ TiF ₆ , HF, KHF ₂ Sb, and F ₃ MoF ₆ and fluoro complex anions such as NH ₄ MnF ₃ and NH ₄ BiF ₄ may be used. Compounds to be produced, BrF ₃ , SF ₄ , SF
Inorganic molecular fluorides such as ₆ , CF ₃ I, CF ₃ OOH, P
Organic fluorine compounds such as (CF ₃ ) ₃ can be exemplified. Further, when the solvent is water, a combination of a fluorine-containing compound and a nonvolatile acid, such as a combination of CaF ₂ and sulfuric acid, can also be used.

The metal compound which can take a trivalent or pentavalent coordination number soluble in a solvent includes Al, Ca, In, Tl
Or a group V element such as P, As, Sb, Bi, etc. Nb, V, which can take a trivalent or pentavalent coordination number
A group of compounds containing a transition metal such as Ti, Cr, Mo, Fe, Co, and Ni.

When adding an amorphous metal oxide in an electrophotographic photoreceptor, it is preferable to add it to a conductive intermediate layer between a conductive substrate and a photosensitive layer.

[0036] The content of the electrophotographic photoreceptor in, preferably 5 to 500 mg / m ² of a metal oxide weight, particularly preferably 10 to 350 mg / m ^2. The weight ratio of the metal oxide to the binder is preferably from 1/300 to 100/1, more preferably at least 10 vol%. 10
It is known that in a state where vol% or more is added, a percolation transition occurs when conductive particles are dispersed in an insulator matrix, and the conductivity in the conductive layer is greatly changed.

The electrophotographic photosensitive member to which the present invention can be applied is not particularly limited. However, a typical one is an electrophotographic photoreceptor having a photosensitive layer provided on the surface of a cylindrical conductive substrate, and a conventionally used method can be widely used to provide the photosensitive layer.

That is, as the conductive substrate, a widely used metal substrate such as aluminum itself may constitute the conductive substrate, or a good conductive layer may be formed on an insulating substrate such as plastic. As a method,
Representative examples are those obtained by vapor deposition or sputtering of a metal or metal oxide such as aluminum or ITO (indium tin oxide), or those obtained by mixing ITO or alumina conductive fine particles with a resin to impart conductivity. is there.

In the formation of the photosensitive layer, an inorganic photoconductor layer may be formed by vapor deposition or the like, but an organic photoconductor layer, in particular, a function separation type containing both a charge transport material and a charge generation material, In particular, it is preferable to form by applying an organic photoreceptor of a type in which each is separately laminated.

The charge generation layer (CGL) is formed by dispersing a charge generation material (CGM) in a binder resin as required. Examples of CGM include metal or metal-free phthalocyanine compounds, azo compounds such as bisazo compounds and trisazo compounds, squarium compounds, azurenium compounds, perylene compounds, indico compounds, quinacridone compounds, polycyclic quinone compounds, cyanine dyes, xanthene dyes, Examples include, but are not limited to, charge transfer complexes comprising poly-N-vinylcarbazole and trinitrofluorenone. These may be used as a mixture of two or more as necessary.

As the binder resin usable for the charge generation layer, for example, polystyrene resin, polyethylene resin, polypropylene resin, polyacryl resin, polymethacryl resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinyl 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, for example, vinyl chloride-acetic acid Vinyl copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, and high-molecular organic semiconductor such as poly-N-vinyl carbazole,
And the like, but are not limited thereto. Among the above, when the imidazole perylene compound is used as the CGM, a preferred binder is polyvinyl butyral resin, and a preferred binder when using TiOPc is a polysilicone resin and a polyvinyl butyral resin, or a mixture of both. No.

The charge transport layer (CTL) 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,
Phenazine derivatives, aminostilbene derivatives, triarylamine derivatives, phenylenediamine derivatives, stilbene derivatives, benzidine derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, 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, a polycarbonate resin, a polyacrylate resin, a polyester resin, a polystyrene resin,
Examples thereof include, but are not limited to, styrene-acrylonitrile copolymer resin, polymethacrylate resin, and styrene-methacrylate copolymer resin.

Further, in order to reduce fatigue deterioration upon repeated use or to improve durability, each of the layers of the photoreceptor is provided with a conventionally known antioxidant, ultraviolet absorber, electron-accepting substance, and surface. An environment-dependent reducing agent such as a modifier and a plasticizer can be added in an appropriate amount as needed.

Further, for the purpose of improving the durability and taking measures against troubles, a non-photosensitive layer such as an intermediate layer (undercoat layer) containing a polyamide resin or the like and a protective layer may be provided as necessary.

Next, the photoreceptor of the present invention can be widely applied to an image forming apparatus and an image forming method using an electrophotographic system. Here, an embodiment of an internal exposure type superimposed color image formation in which the characteristics of the photoreceptor according to the present invention can be best exhibited will be described.

FIG. 1 is a sectional view of a color image forming apparatus showing an example of an image forming apparatus to which the above-described electrophotographic photosensitive member of the present invention is applied.

Reference numeral 10 denotes a drum-shaped photoreceptor. A transparent conductive layer, a conductive intermediate layer according to the present invention, and a charge-transfer layer are provided around a cylindrical substrate formed of a highly transparent polymethyl methacrylate polymer resin. A function-separated organic photosensitive layer comprising a generating layer and a charge transfer layer is formed. 110
Y, 110M, 110C and 110K are yellow (Y), magenta (M), cyan (C) and black (K)
In the corona charging device used in the image forming process of each color, a charging action is performed by corona discharge in order to hold a charge of a predetermined potential to the above-mentioned organic photosensitive layer of the photoconductor 10, and the photoconductor 10 is uniformly charged. Apply potential.

12Y, 12M, 12C and 12K are
FL (phosphor emission), EL (electroluminescence), PL (plasma discharge), LED (light emitting diode), and lamp and light shutter function in which light emitting elements arranged in the axial direction of the photoconductor 10 are arranged in a line. (Magneto-optical effect optical shutter array) in which elements with
PLZT (Transmissive piezoelectric element shutter array), LCS
An image of each color read by a separate image reading device using an exposure optical system that is an image exposure device configured as a unit including an exposure element such as a (liquid crystal shutter) and a selfoc lens as an equal-magnification image forming element. The signals are sequentially taken out of the memory and the exposure optical systems 12Y, 12M, 1
2C and 12K are respectively input as electric signals. The above-mentioned exposure optical systems 12Y, 12M, 12C and 1
Each 2K is attached to a cylindrical holding member 20 and housed inside the substrate of the photoreceptor 10.

The developing devices 13Y, 13M, 13C and 13K are developing devices which use the non-contact developing method for accommodating yellow (Y), magenta (M), cyan (C) and black (K) developers. The developing sleeves 1 rotate in the same direction while maintaining a predetermined gap with respect to the peripheral surface of the photoconductor 10.
30Y, 130M, 130C and 130K.

The developing units 13Y, 13M, 13C and 13K are provided with the above-described corona chargers 110Y, 110Y.
M, charging by 110C and 110K, exposure optical system 1
The electrostatic latent image on the photoconductor 10 formed by the image exposure by 2Y, 12M, 12C and 12K is reversely developed in a non-contact state by applying a developing bias voltage.

An original image is read out by an image reading device separate from the present device, and an image read by an image sensor or an image edited by a computer is temporarily converted into image signals for respective colors of Y, M, C and K. Stored and stored in memory.

At the start of image recording, the photosensitive member 10 is rotated clockwise by the start of the photosensitive member drive motor, and at the same time, the photosensitive member 10 is charged by the charging action of the corona charging device 110Y.
Is started.

After the photoreceptor 10 is applied with an electric potential, the exposure optical system 12Y starts exposure with an electric signal corresponding to a first color signal, that is, an image signal of yellow (Y), and the rotation is performed by rotating and scanning the drum. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer on the surface.

The latent image is reversal-developed by the developing device 13Y in a state where the developer on the developing sleeve is not in contact with the developer, and a yellow (Y) toner image is formed in accordance with the rotation of the photosensitive drum 10.

Next, the photosensitive drum 10 is further provided with a corona charging device 110M on the yellow (Y) toner image.
The exposure is performed by an electric signal corresponding to the second color signal of the exposure optical system 12M, that is, the image signal of magenta (M), and the non-contact reversal development is performed by the developing unit 13M. A magenta (M) toner image is sequentially superimposed on the yellow (Y) toner image.

By the same process, the corona charging device 11
0C, a cyan (C) toner image corresponding to the third color signal by the exposure optical system 12C and the developing device 13C, and a fourth color signal by the corona charging device 110K, the exposure optical system 12K and the developing device 13K. Corresponding black (K) toner images are sequentially superposed, and a color toner image is formed on the peripheral surface within one rotation of the photosensitive drum 10.

These exposure optical systems 12Y, 12M, 12C
Exposure of the organic photosensitive layer of the photoreceptor drum 10 at the temperature of 12 K and 12 K is performed from the inside of the substrate through the transparent substrate described above. Therefore, the exposure of the image corresponding to the second, third, and fourth color signals is performed without any influence from the previously formed toner image, and the same exposure as the image corresponding to the first color signal is performed. It is possible to form an electrostatic latent image. In order to stabilize the temperature inside the photosensitive drum and prevent the temperature from rising due to the heat generated by the exposure optical systems 12Y, 12M, 12C and 12K, a material having good heat conductivity is used for the holding member 20. When the temperature is high, measures such as radiating heat to the outside through a heat pipe can be taken to a level where no problem is caused.

Thus, the color toner image formed on the peripheral surface of the photosensitive drum is sent out from the paper feed cassette 15 by the feed roller 15a in the transfer unit 14a, and is sent to the timing roller 16 by the pair of transport rollers 15b and 15c. The sheet is conveyed, and is transferred onto a transfer sheet P, which is a transfer material fed in synchronization with the toner image on the photoconductor 10, by driving the timing roller 16.

The transfer paper P to which the toner image has been transferred is separated from the peripheral surface of the drum by the removal of the charge in the charge eliminator 14b, and then is carried by the transport driving roller 14c and the driven roller 14d.
The fixing device 17 is moved by the conveying belt 14e stretched between the fixing belts.
Transported to The fixing roller 17 in the fixing device 17
a, the toner is heated and pressed between the pressure rollers 17b to fuse and fix the toner on the transfer paper P, and then a pair of fixing exit rollers 17d
Is discharged from the fixing device 17 by the
The photosensitive drum 10 provided with the photosensitive layer on the cylindrical substrate of the present invention described above is conveyed by the discharge roller 8a and discharged onto the discharge tray 200 at the upper portion of the apparatus via the discharge roller 18. A clear and very good image was obtained.

On the other hand, the photoreceptor 10 from which the transfer paper has been separated is cleaned by a cleaning device 19 with a cleaning blade 19a.
The surface of the photoreceptor 10 is rubbed to remove the residual toner and is cleaned, and the formation of the toner image of the original image is continued or temporarily stopped to start the formation of a new toner image of the original image. The waste toner scraped off by the cleaning blade 19a is removed by the toner conveying screw 19b.
It is discharged to a waste toner container (not shown).

The photoreceptor 10 has a relatively small drum diameter because the exposure optical system is housed in the photoreceptor 10.
The plurality of corona charging devices 110 described above are provided on the outer peripheral surface thereof.
Y, 110M, 110C and 110K, developing unit 13
Y, 13M, 13C and 13K can be provided, and the volume of the apparatus can be made compact by using a small-diameter drum having an outer diameter of 30 mm to 150 mm.

[0063]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto. In the text, “parts” means “parts by weight”.

(Examples) (1) Synthesis of tin oxide sol 65 g of stannic chloride hydrate was mixed with a water / ethanol mixed solution 2
000 cc to obtain a homogeneous solution.

Next, the coprecipitate produced by boiling this is taken out by decantation and washed with distilled water many times. After confirming that there is no reaction of chlorine ions by dropping silver nitrate into the distilled water from which the precipitate has been washed, distilled water is added to the washed precipitate to make the total volume 2000 cc. Further, 40 cc of 30% aqueous ammonia was added, heated in an aqueous solution, and concentrated to obtain a colloidal sol dispersion having a solid content of 8%. It was confirmed by the above-mentioned X-ray diffraction method that the tin oxide in the colloidal sol dispersion had a diameter of about 30 nm and was amorphous.

(2) Formation of conductive intermediate layer 1) A coating solution having the following composition was prepared.

First liquid n-butyl acrylate 10 wt% t-butyl acrylate 35 wt% styrene 27 wt% 2-hydroxyethyl acrylate 28 wt% copolymer latex liquid (solid content 30%) Second liquid n-butyl acrylate 40 wt% styrene Coating latex liquid of 20 wt% glycidyl methacrylate 40 wt% (solid content 30%) Tin oxide sol synthesized by (1), first liquid and second liquid were mixed at a volume ratio of 35:15:50, and the coating liquid was dried. The coating was performed so that the thickness was 0.2 μm and the amount of the conductive agent was 250 mg / m ² .

(3) A photoreceptor was manufactured with the following configuration.

Photoconductor substrate Aluminum cylinder substrate (diameter 30 mm, length 26
0 mm).

Undercoat Layer-1 The following composition was applied on the above substrate by dipping to a layer thickness of 1 μm.

Conductive-treated titanium oxide particles 10 parts Phenol resin 10 parts Silicone oil 0.001 part Methanol / methyl cellosolve = 1/1 20 parts Conductive intermediate layer The conductive intermediate layer liquid as described in (2) is 0. ... 2 μm.

Undercoat Layer-2 The following composition was applied by dipping to a thickness of 0.5 μm.

Alcohol-soluble polyamide resin 10 parts (Toray Amilan CM-8000) Methoxymethylated 6 nylon resin 30 parts (Teijin Scientific Toresin EF-30T) Methanol / butanol 150 parts / 150 parts Charge generation layer (CGL) The composition solution was applied by a dipping method so as to have a film thickness of 0.2 μm.

4 parts of oxytitanium phthalocyanine 2 parts of polyvinyl butyral 2 parts (Slec BM-2 manufactured by Sekisui Chemical) 80 parts of cyclohexanone 115 parts of methyl ethyl ketone Charge transport layer (CTL) The following composition was applied by dipping to a film thickness of 18 μm. .

Amino compound 8 parts Polycarbonate resin 10 parts (Mitsubishi Gas Chemical Iupilon Z-200) Monochlorobenzene / dichloromethane 30 parts / 30 parts (Comparative Example) In the coating liquid of (2), the average particle size is 0.06
μm tin oxide fine powder is dispersed in a liquid obtained by mixing the first liquid and the second liquid, and the film thickness is 0.2 μm.
Coating was performed so as to be 250 mg / m ² .

When the tin oxide powder was measured by X-ray diffraction using CuKα radiation, the black angle 2θ value was 20.
A sharp scattering peak with an apex from ° to 40 ° was observed. The crystallite size determined based on the measurement results is
It was a typical rutile crystal at 41.5 nm.

(4) Performance evaluation (Comparison of performance with actual machine) Each of the example and the comparative example was mounted on a commercially available laser printer KL-2010 (manufactured by Konica), and was heated at 23 ° C. and 55% RH and at 30 ° C. and 80% RH. Was evaluated for a halftone image.

[0078] * 1 Image density unevenness occurred in the halftone portion.

* 2 Black spots on the image, which are probably caused by charge leakage, occurred over the entire surface.

Further, as the photoreceptor for internal exposure using the transparent substrate of FIG. 1, each layer formulation having the same composition as in the above example was applied, and a favorable photoreceptor having high transparency was obtained.

[0081]

According to the present invention, it is possible to provide a method for imparting appropriate conductivity to an intermediate layer (undercoat layer) between the surface of a substrate of an electrophotographic photoreceptor and a photosensitive layer. It does not cause any variation in resistance and has excellent transparency, and has little variation in transparency. The present invention can provide an electrophotographic photosensitive member to which a property imparting method is applied and a method for producing the same.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram of an image forming apparatus of the present invention.

[Explanation of symbols]

Reference Signs List 10 photoconductor (photoconductor drum) 12Y, 12M yellow, magenta exposure optical system (exposure device) 12C, 12K cyan, black exposure optical system (exposure device) 13Y, 13M, 13C, 13K yellow, magenta, cyan, black Developing devices 110Y, 110M, 110C, 110K yellow,
Magenta, cyan, and black corona charging device 15 Paper cassette 16 Timing roller 17 Fixing device 19 Cleaning device P Transfer paper

Claims (8)

[Claims] 1. An electrophotographic photosensitive member having a layer containing at least an amorphous metal oxide conductive agent on a conductive substrate. 2. A method according to claim 1, wherein a photosensitive layer is provided on the conductive substrate, and a conductive intermediate layer is provided between the photosensitive layer and the conductive substrate. The conductive intermediate layer contains the conductive agent. The electrophotographic photoreceptor according to claim 1. 3. The electrophotographic photosensitive member according to claim 1, wherein the conductive agent is conductive particles having a diameter of 1 to 100 nm. 4. The electrophotographic photoconductor according to claim 1, wherein the conductive agent is amorphous tin oxide. 5. An electrophotographic photosensitive member having at least a conductive intermediate layer on a conductive substrate, wherein the conductive intermediate layer contains a colloidal metal oxide sol as a conductive agent. Photoconductor. 6. The electrophotographic photosensitive member according to claim 5, wherein the conductive agent is colloidal tin oxide. 7. A method for producing an electrophotographic photoreceptor having at least a conductive intermediate layer on a conductive substrate, wherein a colloidal metal oxide sol is added as a conductive agent to the conductive intermediate layer. A method for manufacturing an electrophotographic photosensitive member. 8. The method according to claim 7, wherein the conductive agent is a colloidal tin oxide sol.