JP2002318458A - Electrophotographic photoreceptor, method for producing the same, electrophotographic process cartridge using the same and electrophotographic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor capable of preventing the occurrence of leak defects and capable of thoroughly preventing the occurrence of black spots and defects in image quality even after repeated use and to provide a method for producing the photoreceptor, an electrophotographic process cartridge using the photoreceptor and an electrophotographic apparatus. SOLUTION: In the electrophotographic photoreceptor with an undercoat layer having a middle layer 2 between an electrically conductive substrate 1 and a photosensitive layer 3, the middle layer 2 is formed using a coating liquid for forming a middle layer prepared by dispersing fine metal oxide particles in a binder resin after mixing the particles with a resin precursor. Since the degeneration of the binder resin by the fine metal oxide particles is thoroughly prevented and a homogeneous state is obtained, even when the electrophotographic photoreceptor is repeatedly used, the occurrence of pinholes is thoroughly prevented and the occurrence of black spots is thoroughly prevented.

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 in an electrophotographic apparatus such as a copying machine and a laser printer, a method for manufacturing the same, and an electrophotographic process cartridge and an electrophotographic apparatus using the electrophotographic photosensitive member. .

[0002]

2. Description of the Related Art Electrophotographic photoreceptors have been used in electrophotographic apparatuses such as copiers and laser printers because of their high speed and high printing quality. At present, organic photoreceptors using organic photoconductive materials are mainly used as electrophotographic photoreceptors, and the configuration of the photoreceptor is a charge transfer type complex structure, or a photoconductive layer is formed between a charge generation layer and a charge transport layer. Function-separated type photoreceptors have been changed to layers, and function-separated type photoreceptors have received particular attention.

[0003] This function-separated type photoreceptor generally has an intermediate layer, a charge generation layer and a charge transport layer on a conductive substrate. Here, with respect to the improvement of the repetition stability and environmental stability of the photoreceptor, not only the charge generation layer and the charge transport layer but also an intermediate layer having a large portion depending on the intermediate layer are required. ing.

The intermediate layer also plays a major role in preventing image quality defects, and is used to suppress image quality defects caused by defects and stains on the conductive substrate, coating defects such as the charge generation layer, and coating unevenness. The middle layer is indispensable.

In particular, in recent years, in an electrophotographic apparatus, a charging apparatus of a contact charging system which generates less ozone has been frequently used instead of a charging apparatus of a non-contact charging system such as a corotron. When a local high electric field is applied to a locally deteriorated portion of the photoconductor, an electric pinhole is apt to be generated in the deteriorated portion, thereby easily causing an image quality defect. For this reason, a technique for preventing a defect caused by a non-uniform state of the photoreceptor has been particularly strongly required, and for that purpose, an improvement in the intermediate layer has been required.

Therefore, a method of forming an intermediate layer containing a conductive fine powder on a conductive substrate in order to conceal the defects of the conductive substrate and stabilize the electrical characteristics has been taken. I have.

As this method, two kinds of methods are known. The first method is to form a first intermediate layer in which conductive powder is dispersed on an aluminum base material, and further form a second intermediate layer thereon. This is a method of forming an intermediate layer. That is, this is a method in which the intermediate layer is composed of two layers. According to this method, the first intermediate layer performs base material hiding and resistance adjustment, and the second intermediate layer has a charge blocking function.

The second method is a method in which an intermediate layer in which conductive powder is dispersed is applied on a substrate, and this intermediate layer is used as a layer having a blocking function and a resistance adjusting function. That is, this is a method in which the intermediate layer is composed of one layer. According to this method, the number of laminations is one less than in the first method, so that the manufacturing process of the photoconductor can be simplified and the cost can be reduced.

As a method of manufacturing an electrophotographic photosensitive member having such an intermediate layer, a method disclosed in Japanese Patent Application Laid-Open No. Hei 3-136062 has been known. This publication discloses a method of manufacturing an electrophotographic photoreceptor in which an undercoat layer as an intermediate layer is composed of one layer as follows. That is, the method of manufacturing the undercoat layer described in the publication, first, a modified indium oxide, a butyral resin, and a cyclohexane solution are mixed, and a methyl ethyl ketone solution of an isocyanate-based curing agent is added to prepare an undercoat layer coating solution. A method is disclosed in which the undercoat layer coating liquid is spray-coated on an aluminum drum, dried and cured to form an undercoat layer.

[0010]

However, the electrophotographic photosensitive member obtained by the manufacturing method described in the above-mentioned publication has the following problems.

That is, in the above-mentioned electrophotographic photoreceptor, when used repeatedly, black spots may be generated and image defects may occur.

The present invention has been made in view of the above circumstances, and an electrophotographic photoreceptor capable of sufficiently preventing the occurrence of black spots even after repeated use and sufficiently preventing the deterioration of image quality, and a method of manufacturing the same, and An object of the present invention is to provide an electrophotographic process cartridge and an electrophotographic apparatus using an electrophotographic photosensitive member.

[0013]

Means for Solving the Problems The present inventors have examined the above problems and found that when metal oxide particles such as modified indium oxide and butyral resin are suddenly mixed, the modified indium oxide has activity. Therefore, it was considered that the butyral resin and the like were deteriorated, thereby causing pinholes in the intermediate layer, deteriorating the electrical characteristics, and causing black spots when the electrophotographic photosensitive member was repeatedly used.

The inventors of the present invention have made further studies and found that the above problem was solved by mixing metal oxide particles with a resin precursor such as an isocyanate-based curing agent and then mixing with a butyral resin or the like. Find out what can be solved,
The present invention has been completed.

That is, the present invention relates to an electrophotographic photoreceptor having an intermediate layer between a conductive base material and a photosensitive layer, wherein the intermediate layer is obtained by mixing fine metal oxide particles with a resin precursor and then forming a binder resin. It is formed using a coating liquid for forming an intermediate layer obtained by dispersing the coating liquid therein. Further, the present invention provides an electrophotographic photoreceptor having an intermediate layer between a conductive substrate and a photosensitive layer, wherein the intermediate layer causes the metal oxide fine particles to be inert to the metal oxide fine particles. An electrophotographic photoreceptor formed by using a coating liquid for forming an intermediate layer obtained by mixing with an active resin and dispersing in a binder resin different from the inactive resin.

According to these inventions, the situation in which the binder resin is deteriorated by the metal oxide fine particles is sufficiently prevented, and the binder resin is in a homogeneous state. Therefore, in an electrophotographic apparatus having a contact-type charging device, even when repeatedly used, the occurrence of pinholes is sufficiently prevented, and the occurrence of black spots is sufficiently prevented.

Further, according to the present invention, there is provided a method of manufacturing an electrophotographic photoreceptor having an intermediate layer between a conductive substrate and a photosensitive layer, wherein the metal oxide fine particles are mixed with a resin precursor and then mixed with a binder resin. To prepare a coating solution for forming an intermediate layer, using the coating solution for forming an intermediate layer, a step of forming the intermediate layer on the conductive substrate, a photosensitive layer on the intermediate layer Forming an electrophotographic photoreceptor. Further, the present invention provides a method of manufacturing an electrophotographic photoreceptor having an intermediate layer between a conductive substrate and a photosensitive layer, wherein the metal oxide fine particles are formed of an inert resin inert to the metal oxide fine particles. After mixing with the inert resin, dispersed in a binder resin different from the inert resin to prepare a coating solution for forming an intermediate layer, using this coating solution for forming an intermediate layer, the intermediate layer on the conductive substrate Forming,
Forming a photosensitive layer on the intermediate layer.

According to these manufacturing methods, the situation in which the binder resin is deteriorated by the metal oxide fine particles is sufficiently prevented, and a homogeneous state is obtained. Therefore, in the intermediate layer of the obtained electrophotographic photosensitive member, even when the electrophotographic photosensitive member is repeatedly used in the electrophotographic device having the contact-type charging device, the occurrence of pinholes is sufficiently prevented, and the occurrence of black spots is sufficiently prevented. Is prevented. According to this manufacturing method,
In the coating liquid for forming the intermediate layer, the dispersion state of the metal oxide fine particles is improved. For this reason, the storage stability of the coating liquid for forming an intermediate layer is remarkably improved, and the occurrence of image defects is sufficiently prevented, and an electrophotographic photosensitive member having a good resistance value is obtained.

Further, the present invention comprises the above-mentioned electrophotographic photosensitive member, and a contact-type charging device which contacts the surface of the electrophotographic photosensitive member to charge the surface, and is detachable from the main body of the electrophotographic device. An electrophotographic process cartridge characterized in that: The present invention also provides the electrophotographic photosensitive member, a contact-type charging device that contacts the surface of the electrophotographic photosensitive member to charge the surface, and an electrostatic latent image that is formed by exposing the surface of the electrophotographic photosensitive member. An electrophotographic apparatus, comprising: an exposure device that forms an image; a developing device that develops the electrostatic latent image; and a transfer device that transfers the developed image to a transfer medium.

In general, when a contact-type charging device is used as a charging device, if a photosensitive member has a locally deteriorated portion, an electric pinhole is generated in the deteriorated portion due to the application of a local high electric field. And image quality defects are likely to occur. However, according to the electrophotographic process cartridge and the electrophotographic apparatus according to the present invention, since the binder resin is in a homogeneous state in the intermediate layer of the electrophotographic photosensitive member, pinholes are generated even if the electrophotographic photosensitive member is repeatedly used. Is sufficiently prevented, and the occurrence of black spots is sufficiently prevented.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

(Electrophotographic Photoreceptor) First, the electrophotographic photoreceptor of the present invention will be described. The electrophotographic photoreceptor of the present invention is
An intermediate layer is provided between the conductive substrate and the photosensitive layer.

(Intermediate Layer) The intermediate layer can be formed by applying a coating liquid for forming an intermediate layer on a conductive substrate and heating the conductive substrate.

The coating solution for forming the intermediate layer is prepared as follows. That is, first, metal oxide fine particles are mixed with a resin precursor, and then dispersed in a binder resin to prepare the composition.

Examples of the metal oxide fine particles include tin oxide, titanium oxide, zinc oxide, indium oxide, iron oxide, aluminum oxide, silicon oxide, zirconium oxide, and the like.
A conductive substance such as magnesium oxide or copper oxide is used.

The metal oxide fine particles have a particle size of 1
Those having a thickness of 00 nm or less are preferably used. The particle size here means an average primary particle size. If the particle size exceeds 100 nm, the residual potential tends to be high, and good electrical properties tend not to be obtained.

It is necessary for the intermediate layer to have an appropriate resistance in order to obtain leak resistance. Therefore, the metal oxide fine particles may have a powder resistance of about 10 ² to 10 ¹¹ Ω · cm. More preferably, it has a powder resistance of about 10 ⁴ to 10 ¹⁰ Ω · cm. If the powder resistance of the metal oxide fine particles is less than 10 ² Ω · cm, sufficient leakage resistance tends to be not obtained, and if the powder resistance exceeds 10 ¹¹ Ω · cm, the residual potential tends to increase. is there.

As the metal oxide fine particles, tin oxide, titanium oxide, zinc oxide and the like having powder resistance in the above range are particularly preferable from the viewpoint of suppressing the residual potential.

The metal oxide fine particles are preferably contained in the intermediate layer in an amount of 10 to 95% by weight, more preferably 25 to 85% by weight.
It is contained in the range of weight%. If the content is less than 10% by weight, the resistance of the obtained intermediate layer tends to be too high to obtain good electrical properties. If it exceeds 95% by weight, the dispersibility of the metal oxide fine particles is poor. Becoming
There is a tendency that the strength of the intermediate layer becomes insufficient or good image quality characteristics cannot be obtained.

On the other hand, the resin precursor has good dispersibility in the binder resin and is made of an inert material to the metal oxide fine particles. Examples of such a resin precursor include isocyanate compounds, epoxy group-containing prepolymers, phenol compounds, methylol compounds, melamine compounds, unsaturated polyesters, diallyl phthalate, bismaleimide, and imide group-containing prepolymers. The isocyanate compound is preferable because of high dispersibility, and among the isocyanate compounds, a blocked isocyanate compound is particularly preferable. In this case, since the gelation is sufficiently suppressed, the storage stability of the coating solution for forming the intermediate layer is improved, and the production cost can be reduced.

The amount of the resin precursor is preferably 5 to 30 parts by weight based on 100 parts by weight of the metal oxide fine particles.
More preferably, it is 10 to 25 parts by weight. When the addition amount of the resin precursor is less than 5 parts by weight, the binder resin described later is easily deteriorated by the metal oxide fine particles, and
The dispersibility of the metal oxide fine particles tends to deteriorate,
If the amount exceeds the weight part, the strength of the intermediate layer tends to decrease.

When mixing or dispersing the metal oxide fine particles and the resin precursor, a solvent is added as necessary. Any solvent may be used as long as it dissolves the resin precursor, such as a hydrocarbon solvent, a halogenated hydrocarbon solvent, methanol, n-butyl alcohol, an alcohol solvent such as methoxypropanol, a ketone solvent such as methyl ethyl ketone, Any known solvent such as an aromatic solvent, an ester solvent, and an ether solvent can be used. These may be used alone or in combination of two or more.

The mixing or dispersion of the resin precursor and the metal oxide fine particles can be carried out by a known method such as a roll mill, a ball mill, a vibrating ball mill, an attritor, a sand mill, a colloid mill, a paint shaker and the like.

The mixing or dispersing temperature is usually from 0 to 4
0 ° C. When mixing or dispersing using a solvent, the temperature is usually lower than the boiling point of the solvent used.
In this case, the temperature adjustment is preferably performed by flowing water cooling, because the temperature is prevented from rising during dispersion.

The binder resin is not particularly limited as long as the above resin precursor can be dispersed, and examples thereof include an acetal resin such as polyvinyl butyral, a polyvinyl alcohol resin, a casein, a polyamide resin, a cellulose resin, a gelatin, and a polyurethane resin. , Polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol resin, phenol-formaldehyde resin, melamine resin, etc. A polymer resin compound or the like is used.

It is preferable to add resin particles to the coating liquid for forming the intermediate layer from the viewpoint of preventing the occurrence of moire patterns. As the resin particles, for example, silicone resin,
PMMA resin or the like is used, and its particle size is 1 to 10 μm.
Is preferable, and 2 to 7 μm is more preferable.

Further, various additives may be added to the coating solution for forming the intermediate layer in order to improve electric characteristics, environmental stability and image quality.

Examples of such additives include quinone compounds such as chloranyl, bromoanil, and anthraquinone; tetracyanoquinodimethane compounds; 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitro-9- Fluorenone compounds such as fluorenone; 2- (4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole and 2,5-bis (4-naphthyl) -1,
Oxadiazole compounds such as 3,4-oxadiazol and 2,5-bis (4-diethylaminophenyl) 1,3,4oxadiazole; xanthone compounds; thiophene compounds; 3,3 ′, 5,5 'Electron-transporting substances such as diphenoquinone compounds such as tetra-t-butyldiphenoquinone, electron-transporting pigments such as polycyclic condensed and azo-based compounds, silane coupling agents, zirconium chelate compounds, titanium chelate compounds, and aluminum chelate compounds ,
Known materials such as titanium alkoxide compounds and organic titanium compounds are used.

Examples of the silane coupling agent include:
Vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane, β-
(3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (amino Ethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ
-Aminopropylmethylmethoxysilane, N, N-bis
(β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane and the like.

Examples of the zirconium chelate compound include zirconium butoxide, ethyl zirconium acetoacetate, zirconium triethanolamine, acetylacetonate zirconium butoxide, ethyl zirconium butoxide acetoacetate, zirconium acetate, zirconium oxalate, zirconium lactate, zirconium phosphonate, Examples include zirconium octoate, zirconium naphthenate, zirconium laurate, zirconium stearate, zirconium isostearate, zirconium butoxide methacrylate, zirconium butoxide stearate, and zirconium butoxide isostearate.

Examples of the titanium chelate compound include tetraisopropyl titanate, tetra-n-butyl titanate, butyl titanate dimer,
(2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate ammonium salt, titanium lactate, titanium lactate ethyl ester, titanium triethanol aminate, polyhydroxytitanium stearate, etc. No.

Examples of the aluminum chelate compound include aluminum isopropylate, monobutoxyaluminum diisopropylate, aluminum butyrate, diethyl acetoacetate aluminum diisopropylate, and aluminum tris (ethyl acetoacetate).

These compounds can be used alone or as a mixture or a polycondensate of a plurality of compounds.

Further, an antioxidant may be added to the coating solution for forming the intermediate layer. Examples of the antioxidant include a hindered phenol antioxidant, a hindered amine antioxidant, paraphenylenediamine, an arylalkane, hydroquinone, spirochroman, spiroidanone and derivatives thereof, an organic sulfur-based antioxidant, and an organic phosphorus-based antioxidant. And antioxidants.

Examples of the above hindered phenolic antioxidants include 2,6-di-t-butyl-4-methylphenol, styrenated phenol, and n-octadecyl-3-.
(3 ', 5'-di-t-butyl 4'-hydroxyphenyl)
-Propionate, 2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2-t-butyl-
6- (3′-tert-butyl-5′-methyl-2′-hydroxybenzyl) -4-methylphenyl acrylate, 4,
4'-butylidene-bis- (3-methyl-6-t-butyl-phenol), 4,4'-thio-bis- (3-methyl
6-t-butyl phenol), 1,3,5-tris (4
-T-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, tetrakis- [methylene-3
-(3 ', 5'-di-t-butyl-4'-hydroxy-phenyl) propionate] -methane, 3,9-bis [2- [3
-(3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5]
Undecane and the like.

The hindered amine antioxidants include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate. , 1- [2- [3-
(3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-t
-Butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine, 8-
Benzyl-7,7,9,9-tetramethyl-3-octyl-1,3,8-triazaspiro [4,5] undecane-
2,4-dione, 4-benzoyloxy-2,2,6
6-tetramethylpiperidine, dimethyl succinate-1-
(2-hydroxyethyl) -4-hydroxy-2,2,
6,6-tetramethylpiperidine polycondensate, poly [[6-
(1,1,3,3-tetramethylbutyl) imino-1,
3,5-Triazine-2,4-diimyl] [(2,2
6,6-tetramethyl-4-piperidyl) imino] hexamethylene [(2,3,6,6-tetramethyl-4-piperidyl) imino]], 2- (3,5-di-t-butyl-4) -Hydroxybenzyl) -2-n-butylmalonic acid bis (1,
2,2,6,6-pentamethyl-4-piperidyl), N,
N'-bis (3-aminopropyl) ethylenediamine-2,
4-bis [N-butyl-N- (1,2,2,6,6-pentamethyl-4piperidyl) amino] -6-chloro-1,
3,5-triazine condensates and the like.

The organic sulfur-based antioxidants include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-
3,3′-thiodipropionate, pentaerythritol-tetrakis- (β-lauryl-thiopropionate), ditridecyl-3,3′-thiodipropionate,
2-mercapto benzimidazole and the like.

Examples of the organic phosphorus antioxidant include trisnonylphenyl phosphite, triphenyl phosphite, tris (2,4-di-t-butylphenyl) -phosphite and the like.

The above-mentioned organic sulfur-based and organic phosphorus-based antioxidants are called secondary antioxidants, and when used in combination with the above-mentioned phenol-based or amine-based primary antioxidants, their synergistic effects allow the electrophotographic photosensitive agent to be used. Body deterioration can be further prevented.

When the coating liquid for forming an intermediate layer is thus obtained, the coating liquid for forming an intermediate layer is coated on a conductive substrate and heated to cure the resin precursor.

As a method of applying the coating solution for forming an intermediate layer,
Conventional methods such as a blade coating method, a Meyer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, and a curtain coating method can be used. When the required thickness cannot be obtained by one coating, the required thickness can be obtained by performing multiple coatings. In the case of performing multiple coatings, the heat treatment may be performed for each coating, or may be performed collectively after multiple coatings.

The curing temperature can be arbitrarily set according to the type of the resin precursor, but is usually set to 100 ° C. or higher, more preferably 150 ° C. or higher. The curing time can be arbitrarily set according to the type of the resin precursor, but is preferably 30 minutes to 5 hours.

Thus, an intermediate layer is obtained on the conductive substrate, and the intermediate layer preferably has a Vickers strength of 35 to 200. If the Vickers strength is less than 35, sufficient leak resistance tends not to be obtained, and if it exceeds 200, the intermediate layer tends to become brittle.

Further, as for the thickness of the intermediate layer, if the thickness is less than 3 μm, there is a tendency that the intermediate layer does not have sufficient leak resistance. On the other hand, when the thickness exceeds 30 μm, the effect of the intruding substance from the outside is easily prevented, so that the leak resistance is improved, but the film formation becomes difficult, and the image quality tends to deteriorate due to an increase in the residual charge. There is. Therefore, the thickness of the intermediate layer is preferably set in the range of 3 to 30 μm.

The resistance of the intermediate layer is 10 ⁴ to 10 ¹⁰ Ω ·
cm. If the resistance value is less than 10 ⁴ Ω · cm, sufficient leak resistance tends not to be obtained.
If it exceeds 0 ¹⁰ Ω · cm, the residual potential tends to increase if it is too high. The resistance value is controlled by controlling the resistance value of the metal oxide fine particles themselves and the amount added to the binder resin according to the resistance value, and controlling the dispersibility of the metal oxide fine particles in the binder resin. Can be.

Further, from the viewpoints of improving the electrical characteristics, improving the image quality, maintaining the image quality, and improving the adhesiveness of the photosensitive layer, the intermediate layer transfers electric charge from the photosensitive layer between the intermediate layer and the photosensitive layer. It may have a second intermediate layer having a blocking function.

The second intermediate layer is made of an acetal resin such as polyvinyl butyral, polyvinyl alcohol resin, casein, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacryl resin,
In addition to polymer resins such as acrylic resin, polyvinyl chloride resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, and melamine resin, silicon, zirconium,
It is composed of an organometallic compound containing titanium, aluminum, manganese atom and the like. These compounds can be used alone or as a mixture or a polycondensate of a plurality of compounds.

Above all, organometallic compounds containing silicon or zirconium are excellent in performance such as low residual potential and little change in potential due to environment, and little change in potential due to repeated use.

Examples of organometallic compounds containing silicon include vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane,
β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (Aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl)-
γ-aminopropylmethylmethoxysilane, N, N-bis
(β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane,
Vinyltriethoxysilane, vinyltris (2-methoxyethoxysilane), 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N- 2- (aminoethyl) 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) 3-aminopropylmethyldimethoxysilane, 3-
Aminopropyltriethoxysilane, N-phenyl-3
-Aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane and the like. Among them, particularly, vinyltriethoxysilane, vinyltris (2-methoxyethoxysilane), 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl)
Ethyltrimethoxysilane, N-2- (aminoethyl) 3
-Aminopropyltrimethoxysilane, N-2- (aminoethyl) 3-aminopropylmethyldimethoxysilane,
Preferred are silane coupling agents such as 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-chloropropyltrimethoxysilane.

Examples of organometallic compounds containing zirconium include zirconium butoxide, ethyl zirconium acetoacetate, zirconium triethanolamine,
Acetylacetonate zirconium butoxide, ethyl zirconium butoxide acetoacetate, zirconium acetate, zirconium oxalate, zirconium lactate, zirconium phosphonate, zirconium octanoate, zirconium naphthenate, zirconium laurate, zirconium stearate, zirconium isostearate, zirconium methacrylate, zirconium butoxide,
Zirconium butoxide stearate, zirconium butoxide isostearate and the like can be mentioned.

Examples of the organometallic compound containing a titanium atom include tetraisopropyl titanate, tetra-normal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octate Len glycolate, titanium lactate ammonium salt, titanium lactate, titanium lactate ethyl ester, titanium triethanol aminate, polyhydroxytitanium stearate and the like.

Examples of the organometallic compound containing an aluminum atom include aluminum isopropylate, monobutoxyaluminum diisopropylate, aluminum butyrate, diethylacetoacetate aluminum diisopropylate, and aluminum tris (ethylacetoacetate). .

The second intermediate layer also plays a role of electrical blocking in addition to the improvement of wettability of the upper layer. However, if the thickness is too large, the electrical barrier becomes too strong, and the sensitivity is lowered. There is a tendency for the potential to increase due to repetition, and when it is too small, sufficient blocking properties cannot be obtained, and the occurrence of black spots tends to be prevented. Therefore, when forming the second intermediate layer, its thickness is preferably set in the range of 0.1 to 3 μm.

The case where the coating solution for forming the intermediate layer is prepared by using a resin precursor has been described above. Instead of the resin precursor, the coating solution is inert to the metal oxide fine particles and is used together with the binder resin. Different inert resins may be used.

As such an inert resin, a phenol resin and a melamine resin are preferably used.

The solvent used for mixing or dispersing the metal oxide fine particles and the inert resin is not particularly limited as long as the solvent can dissolve the inert resin. Alternatively, the same solvent as that used for dispersion is used.

The preparation of the coating solution for forming the intermediate layer is carried out in the same manner as in the case of using the resin precursor, except that the resin precursor is replaced with an inert resin.

(Layer Structure of Electrophotographic Photoreceptor) Next, the specific layer structure of the electrophotographic photosensitive member of the present invention will be described.
1 to 6 are cross-sectional views showing various layer configurations of the electrophotographic photosensitive member. The electrophotographic photosensitive member shown in FIG.
And an intermediate layer 2 provided on the conductive substrate 1 and an intermediate layer 2
And a photosensitive layer 3 provided thereon. In the electrophotographic photoreceptor shown in FIG. 2, the photosensitive layer 3 of FIG.
1 and a charge transport layer 32, FIG.
The electrophotographic photoreceptor shown in FIG. 1 has a protective layer 5 further provided on the photosensitive layer 3 of the electrophotographic photoreceptor of FIG. 1, and the electrophotographic photoreceptor shown in FIG. Transport layer 32
The electrophotographic photoreceptor shown in FIG. 5 further includes a protective layer 5 on the intermediate layer 2 and the photosensitive layer 3 of the electrophotographic photoreceptor shown in FIG.
The electrophotographic photoreceptor shown in FIG. 6 has a second intermediate layer 4 between the intermediate layer 2 and the charge generation layer 31 of the electrophotographic photoreceptor of FIG. 4 is provided. The electrophotographic photosensitive member of the present invention may have any of the above-mentioned layer configurations.

Hereinafter, the conductive substrate 1, the charge generation layer 31, the charge transport layer 32, the protective layer 5, and the photosensitive layer 3 in the electrophotographic photosensitive member will be described.

(Conductive Substrate) The conductive substrate 1 may be a metal drum of aluminum, copper, iron, stainless steel, zinc, nickel or the like, or aluminum, copper, gold, silver on a sheet, paper, plastic or glass. , Platinum, palladium, titanium, nickel-chromium alloy, stainless steel, copper-indium alloy and other metals or indium oxide, those deposited with a conductive metal compound such as tin oxide, sheets,
Laminated metal foil on paper, plastic or glass, or carbon black, indium oxide,
A material obtained by dispersing tin oxide, antimony oxide powder, metal powder, copper iodide, or the like in a binder resin, and applying the resultant to a sheet, paper, plastic, or glass, and the like is used.

The shape of the conductive substrate 1 is not limited to a drum shape, but may be a sheet shape or a plate shape.

When the conductive substrate 1 is a metal drum, the metal drum may be a raw tube, or may be subjected to mirror cutting, etching, anodic oxidation, rough cutting, centerless grinding,
Surface treatment such as sandblasting and wet honing may be performed. However, it is preferable to use a conductive substrate 1 that has been subjected to a surface treatment. In this case, the surface of the base material is roughened, and it is possible to prevent grain-like density unevenness (moire pattern) due to interference light that may be generated in the photosensitive layer when a coherent light source such as a laser beam is used. Becomes

(Charge Generating Layer) The charge generating layer 31 is usually formed by dispersing a charge generating substance and a binder resin in an organic solvent, applying a coating liquid for forming a charge generating layer, and drying.

As the charge generating substance, any known charge generating substance can be used, but phthalocyanine pigments are preferably used because they have particularly excellent charge generating functions. In this case, an electrophotographic photosensitive member having particularly high sensitivity and excellent repetition stability can be obtained. Also,
The phthalocyanine-based pigment generally has several crystal types, and any crystal type can be used as long as it is a pigment capable of obtaining the desired sensitivity. Specific examples of particularly preferably used charge generating substances include compounds represented by the following structural formulas (1) to (9).

[0075]

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[0076]

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The above-mentioned charge generating substance is prepared by converting a pigment crystal produced by a known method into an automatic mortar, a planetary mill, a vibration mill, CF
It can be produced by mechanical dry pulverization with a mill, roller mill, sand mill, kneader or the like, or by wet pulverization using a ball mill, mortar, sand mill, kneader or the like together with a solvent after dry pulverization. Solvents used in the above treatment include aromatics (toluene, chlorobenzene, etc.), amides (dimethylformamide, N
-Methylpyrrolidone, etc.), aliphatic alcohols (methanol, ethanol, butanol, etc.), aliphatic polyhydric alcohols (ethylene glycol, glycerin, polyethylene glycol, etc.), aromatic alcohols (benzyl alcohol, phenethyl alcohol, etc.), esters (Acetate, butyl acetate, etc.), ketones (acetone, methyl ethyl ketone, etc.), dimethyl sulfoxide, ethers (diethyl ether, tetrahydrofuran, etc.), a mixed solvent of two or more of these, a mixed solvent of water and these organic solvents Is raised. The amount of the solvent used is 1 to 200 parts by weight, preferably 10 to 1 part by weight, per 100 parts by weight of the pigment crystal.
Used in the range of 00 parts by weight. The treatment temperature is in the range of 0 ° C to the boiling point of the solvent, preferably 10 to 60 ° C. Further, at the time of pulverization, a grinding aid such as salt and sodium nitrate can be used. The grinding aid may be used 0.5 to 20 times, preferably 1 to 10 times the weight of the pigment. Further, the crystal of the pigment crystal produced by a known method can be controlled by acid pasting or a combination of acid pasting and the above-mentioned dry pulverization or wet pulverization. As the acid used for acid pasting, sulfuric acid is preferable, and one having a concentration of 70 to 100%, preferably 95 to 100% is used.
-100 ° C, preferably 0-60 ° C.
The amount of concentrated sulfuric acid is set in the range of 1 to 100 times, preferably 3 to 50 times the weight of the pigment crystals. As a solvent to be precipitated, water or a mixed solvent of water and an organic solvent is used in an arbitrary amount. The temperature for the precipitation is not particularly limited, but is preferably cooled with ice or the like from the viewpoint of preventing heat generation.

The binder resin can be selected from insulating resins and organic photoconductive polymers such as poly-N-vinyl carbazole, polyvinyl anthracene, polyvinyl pyrene and polysilane. Preferred binder resins include, among insulating resins, polyvinyl acetal resin, polyarylate resin (polycondensate of bisphenol A and phthalic acid, etc.), polycarbonate resin, polyester resin, phenoxy resin, vinyl chloride-vinyl acetate copolymer , Polyamide resin, acrylic resin, polyacrylamide resin, polyvinylpyridine resin, cellulose resin,
Examples include, but are not limited to, urethane resins, epoxy resins, caseins, polyvinyl alcohol resins, polyvinyl pyrrolidone resins, and the like. Among them, polyvinyl acetal resin is particularly preferably used. These binder resins can be used alone or in combination of two or more.

The compounding ratio (weight ratio) of the charge generating substance to the binder resin is preferably in the range of 10: 1 to 1:10.

Examples of the solvent for preparing the dispersion for forming a charge generation layer include known organic solvents, for example, alcohols and the like.
It can be arbitrarily selected from aromatic, halogenated hydrocarbon, ketone, ketone alcohol, ether, ester and the like. For example, methanol, ethanol, n
-Propanol, iso-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride,
Usual organic solvents such as chloroform, chlorobenzene, and toluene can be used.

These solvents can be used alone or in combination of two or more. At the time of mixing, any solvent can be used as long as it can dissolve the binder resin.

A small amount of silicone oil can be added to the dispersion for forming the charge generation layer as a leveling agent for improving the smoothness of the coating film.

As a method for dispersing the charge generating substance in the binder resin, a method such as a roll mill, a ball mill, a vibration ball mill, an attritor, a sand mill, a colloid mill, and a paint shaker can be used. At this time, it is effective that the metal oxide fine particles have a particle size of 0.5 μm or less, preferably 0.3 μm or less, and more preferably 0.15 μm or less.

Examples of the method of applying the above-mentioned dispersion for forming a charge generation layer include ordinary methods such as blade coating, wire bar coating, spray coating, dip coating, bead coating, air knife coating, and curtain coating. A method can be used.

Further, various additives may be added to the coating solution for the charge generation layer in order to improve electric characteristics and image quality. As such additives, the same additives as those used for the intermediate layer are used.

The charge generating layer is provided with an antioxidant, a photo-oxidizing agent, and a photo-oxidizing gas for the purpose of preventing deterioration of the charge generating layer due to ozone or oxidizing gas generated in the electrophotographic apparatus, or light or heat. Additives such as stabilizers can be added.

As the antioxidant, the same antioxidant as that used for the intermediate layer can be used.

Examples of the light stabilizer include benzophenone derivatives, benzotriazole derivatives, dithiocarbamate derivatives, tetramethylpiperidine derivatives, and the like.

The benzophenone-based light stabilizer includes:
2-hydroxy-4-methoxy benzophenone, 2-
Hydroxy-4-octoxybenzophenone, 2,
2'-di-hydroxy-4-methoxy benzophenone and the like.

The benzotriazole-based light stabilizer includes 2-(-2'-hydroxy-5'methylphenyl-).
-Benzotriazole, 2- [2'-hydroxy-3'-
(3 ", 4", 5 ", 6" -tetra-hydrophthalimido-methyl) -5'-methylphenyl] -benzotriazole, 2-(-2'-hydroxy-3'-t-butyl 5 '
-Methylphenyl-)-5-chlorobenzotriazole, 2- (2'-hydroxy-3'-t-butyl 5'-methylphenyl-)-5-chlorobenzotriazole,
2- (2'-hydroxy-3 ', 5'-t-butylphenyl-)-benzotriazole, 2- (2'-hydroxy-5'
-T-octylphenyl) -benzotriazole, 2-
(2'-hydroxy 3 ', 5'-di-t-amyl phenyl-)-benzotriazole and the like.

Other light stabilizers include 2,4, di-
t-butylphenyl 3 ', 5'-di-t-butyl-4'-
Hydroxybenzoate, nickel dibutyl-dithiocarbamate and the like.

The charge generation layer may contain at least one kind of electron accepting substance for the purpose of improving sensitivity, reducing residual potential, and reducing fatigue during repeated use. Examples of the electron-accepting substance that can be used in the charge generation layer include succinic anhydride, maleic anhydride, dibromomaleic anhydride, phthalic anhydride, tetrabromophthalic anhydride, tetracyanoethylene, tetracyanoquinodimethane, and o-dichloromethane. Examples include nitrobenzene, m-dinitrobenzene, chloranil, dinitroanthraquinone, trinitrofluorenone, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, and phthalic acid. Of these, fluorenone-based, quinone-based, and benzene derivatives having an electron-withdrawing substituent such as Cl, CN, and NO ₂ are particularly preferable.

The charge generation layer can be formed by vacuum deposition of a charge generation material without using an organic solvent as described above.

(Charge Transporting Layer) As the charge transporting substance contained in the charge transporting layer, any known charge transporting substance can be used, and examples thereof include the following.

That is, oxadiazole derivatives such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole; 1,3,5-triphenyl-pyrazoline and 1- [pyridyl- ( 2) pyrazoline derivatives such as] -3- (p-diethylaminostyryl) -5- (p-diethylaminostyryl) pyrazoline; triphenylamine, triphenylamine
(P-methyl) phenylamine, N, N'-bis (3,4-dimethylphenyl) biphenyl-4-amine, dibenzylaniline, 9,9-dimethyl-N, N'-di (p-tolyl)
Aromatic tertiary amino compounds such as fluorenone-2-amine; N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1-biphenyl] -4,4'-diamine Aromatic tertiary diamino compounds; 1,2,4- such as 3- (4′-dimethylaminophenyl) -5,6-di- (4′-methoxyphenyl) -1,2,4-triazine
Triazine derivatives; hydrazone derivatives such as 4-diethylaminobenzaldehyde-1,1-diphenylhydrazone, 4-diphenylaminobenzaldehyde-1,1-diphenylhydrazone, [p- (diethylamino) phenyl] (1-naphthyl) phenylhydrazone; Quinazoline derivatives such as phenyl-4-styryl-quinazoline; benzofuran derivatives such as 6-hydroxy-2,3-di (p-methoxyphenyl) -benzofuran;
Α-stilbene derivatives such as (2,2-diphenylvinyl) -N, N′-diphenylaniline; enamine derivatives;
Carbazole derivatives such as -ethylcarbazole; hole transport substances such as poly-N-vinylcarbazole and derivatives thereof; or quinone-based compounds such as chloranyl, bromoanil, and anthraquinone; tetracyanoquinodimethane-based compounds; Trinitrofluorenone, 2,
Fluorenone compounds such as 4,5,7-tetranitro-9-fluorenone; 2- (4-biphenyl) -5- (4-t-
(Butylphenyl) -1,3,4-oxadiazole, 2,5-bis (4-naphthyl) -1,3,4-oxadiazole, 2,5-bis (4-diethylaminophenyl)
Oxadiazole compounds such as 1,3,4 oxadiazole; xanthone compounds; thiophene compounds;
Examples thereof include an electron transporting substance such as a diphenoquinone compound such as 3 ′, 5,5′tetra-t-butyldiphenoquinone, and a polymer having a group consisting of the compound described above in a main chain or a side chain. One or two of these charge transport materials may be used.
More than one species can be used in combination.

As the binder resin for the charge transport layer, any known binder resin can be used, but a resin capable of forming an electrically insulating film is preferable. Examples of such resin capable of forming an electrically insulating film include polycarbonate resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl acetate resin, and styrene-butadiene copolymer. Copolymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin. Silicon-alkyd resin,
Phenol-formaldehyde resin, styrene-alkyd resin, poly-N-carbazole, polyvinyl butyral, polyvinyl formal, polysulfone, casein, gelatin, polyvinyl alcohol, ethyl cellulose, phenol resin, polyamide, carboxy-methyl cellulose, vinylidene chloride polymer wax, polyurethane And the like, but are not limited thereto. These binder resins are used alone or as a mixture of two or more kinds. Among them, polycarbonates are particularly excellent in terms of compatibility with a charge transport substance, solubility in a solvent, and strength. Resins, polyester resins, methacrylic resins, and acrylic resins are preferably used.

The compounding ratio (weight ratio) of the binder resin and the charge transporting material can be arbitrarily set according to the required sensitivity. However, depending on the compounding ratio, the electric characteristics are reduced or the film strength is reduced. You need to be careful as it will drop.

The charge transport layer is prepared by dispersing a charge transport substance and a binder resin in an organic solvent to prepare a coating solution for forming a charge transport layer, and applying the coating solution for forming a charge transport layer to a charge generation layer and the like. It can be obtained by drying.

As the organic solvent, dioxane, tetrahydrofuran, methylene chloride, chloroform,
Normal organic solvents such as chlorobenzene and toluene are used, and these can be used alone or in combination of two or more.

As the above-mentioned coating method, a usual method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method and a curtain coating method can be used.

The thickness of the charge transport layer is usually from 5 to 50 μm, preferably from 10 to 35 μm.

The charge transport layer contains an antioxidant, a light stabilizer and the like in the charge transport layer for the purpose of preventing the deterioration of the photosensitive member due to ozone or oxidizing gas generated in the electrophotographic apparatus, or light or heat. Can be added.

The same antioxidant and light stabilizer as those used in the charge generation layer can be used.

(Protective Layer) The protective layer is used in the photosensitive layer having a laminated structure to prevent a chemical change of the charge transport layer during charging and to further improve the mechanical strength of the photosensitive layer. This protective layer is formed by including a conductive material in a suitable binder resin.

Examples of the conductive material include metallocene compounds such as N, N'-dimethylferrocene, and N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1'-biphenyl]. Aromatic amine compounds such as -4,4'-diamine, molybdenum oxide, tungsten oxide, antimony oxide, tin oxide, titanium oxide, indium oxide, and carriers of solid solutions of tin oxide and antimony or antimony oxide (each having a molecular dispersion But not limited thereto, or a mixture thereof, or a mixture of these metal oxides in a single metal oxide particle, or a coating thereof.

As the binder resin used for this protective layer, polyamide resin, polyvinyl acetal resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinylketone resin,
Known resins such as a polystyrene resin, a polyacrylamide resin, a polyimide resin, and a polyamideimide resin are used, and these can be crosslinked and used as necessary.

The thickness of the protective layer is usually 1 to 20 μm, preferably 2 to 10 μm.

The protective layer can be obtained by applying a coating liquid for forming a protective layer to a charge transport layer or the like and drying the coating solution.

As a method of applying the coating liquid for forming a protective layer,
Conventional methods such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, and a curtain coating method can be used.

Examples of the solvent used for the protective layer forming coating solution include ordinary organic solvents such as dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, and toluene. These organic solvents can be used alone or in combination of two or more. However,
Solvents that hardly dissolve the lower layer are preferred.

(Photosensitive Layer) Here, the case where the photosensitive layer 3 is composed of a single layer and has a charge generating ability and a charge transporting ability will be described.

The photosensitive layer 3 is not particularly limited as long as it is made of a material having a charge generating function and a charge transporting function. For example, it is made of a charge generating material, a charge transporting material, a binder resin and the like.

The thickness of the photosensitive layer 3 is generally 5 to 50 μm.
m, preferably in the range of 10 to 40 μm.

The photosensitive layer 3 can be obtained by applying a photosensitive layer forming coating solution for forming the layer 3 to the conductive substrate 1 or the intermediate layer 2 and drying. The coating liquid for forming a photosensitive layer can be obtained by dispersing a material having a charge generation function and a charge transport function and a binder resin in a solvent.

As the above-mentioned solvent, the same solvents as the above-mentioned solvents for the dispersion for forming a charge generation layer can be used.

The application of the coating solution for forming the photosensitive layer is performed by using the same coating method as the coating solution for forming the charge generation layer.

(Electrophotographic process cartridge)
The electrophotographic process cartridge of the present invention will be described. FIG. 7 is a schematic sectional view showing an example of an electrophotographic apparatus provided with the electrophotographic process cartridge of the present invention. The electrophotographic apparatus shown in FIG. 7 includes an electrophotographic apparatus main body, and the electrophotographic apparatus main body includes a developing device 11 and a transfer member 1.
2, the fixing device 15 and the mounting rail 16. Further, the electrophotographic apparatus has an electrophotographic process cartridge 17. The electrophotographic process cartridge 17 includes an electrophotographic photosensitive member 7 in a housing 18.
The electrophotographic process cartridge 1 supports the contact charging device 8, the exposure device 10, and the cleaning device 13 integrally.
7 can be mounted on a mounting rail 16. The contact-type charging device 8 has a contact-charging member. The contact-charging member is disposed so as to be in contact with the surface of the photoconductor, and applies a voltage directly and uniformly to the electrophotographic photoconductor 7. The surface of the photoconductor is charged to a predetermined potential.

Here, the contact-type charging member will be described in more detail. Examples of the contact charging member include metals such as aluminum, iron, and copper; conductive polymer materials such as polyacetylene, polypyrrole, and polythiophene; polyurethane rubber, silicone rubber, and epichlorohydrin rubber;
Ethylene propylene rubber, acrylic rubber, fluorine rubber,
A material in which metal oxide fine particles such as carbon black, copper iodide, silver iodide, zinc sulfide, and silicon carbide are dispersed in an elastomer material such as styrene-butadiene rubber or butadiene rubber can be used.

Examples of the above metal oxides include Z ₂ O, Sn
O ₂ , TiO ₂ , In ₂ O ₃ , MoO _{3, and the} like, or a composite oxide thereof are given.

Further, the contact charging member may be made of a material obtained by adding perchlorate to the above-mentioned elastomer material to impart conductivity.

Further, a coating layer is provided on the surface of the contact charging member.
It may be provided. In this case, the material forming the coating layer
N-alkoxymethylated nylon, cellulose
Resin, vinyl pyridine resin, phenol resin, polyurethane
Tan, polyvinyl butyral, melamine and the like,
These are used alone or in combination. Also,
As a material for forming the coating layer, an emulsion resin material
Material, such as acrylic resin emulsion, polyester tree
Fat emulsions, polyurethanes, especially soap-free
An emulsion resin synthesized by emulsion polymerization,
It can also be used. These emulsion resin materials
To further adjust the resistivity, the conductive agent particles are further separated.
And may contain antioxidants to prevent deterioration.
You can also have. In addition, when forming the coating layer,
Levelin is added to the emulsion resin to improve film properties.
Agents or surfactants may also be included. Ma
The shape of the contact charging member may be a roller type,
Examples include a blade type, a belt type, and a brush type. Sa
Further, the resistance of the contact charging member is preferably 10 ⁰
-10¹⁴Ωcm, more preferably 10^Two-10¹²Ωcm
Range. The voltage applied to the contact charging member
Can be either direct current or alternating current.
They may be superimposed.

According to the electrophotographic process cartridge 17, the binder resin in the intermediate layer 2 of the electrophotographic photosensitive member 7 is sufficiently prevented from being deteriorated, and the intermediate layer 2 is in a uniform state. Therefore, when the process cartridge 17 is mounted on the main body of the electrophotographic apparatus to constitute the electrophotographic apparatus, even if a high electric field is repeatedly applied to the surface of the electrophotographic photosensitive member 7 by the contact charging member repeatedly, the The occurrence of holes is sufficiently prevented, the occurrence of black spots is sufficiently prevented,
As a result, deterioration of image quality is sufficiently prevented.

The electrophotographic process cartridge 17 shown in FIG.
Although the contact-type charging device 8, the exposure device 10, and the cleaning device 13 are integrally supported, the electrophotographic process cartridge of the present invention may support at least the contact-type charging device 8 except for the electrophotographic photosensitive member 7. I just need. However, in this case, when the electrophotographic apparatus is configured by the electrophotographic process cartridge 17 and the electrophotographic apparatus main body, the electrophotographic apparatus includes the developing device 11, the transfer member 12, and the fixing device 1.
5, a mounting rail 16, an electrophotographic photoreceptor 7, a contact-type charging device 8, an exposure device 10, and a cleaning device 13.

(Electrophotographic Apparatus) Finally, the electrophotographic apparatus of the present invention will be described. FIG. 8 is a schematic sectional view showing an embodiment of an electrophotographic apparatus provided with the electrophotographic photosensitive member of the present invention. As shown in FIG. 8, the electrophotographic apparatus includes an electrophotographic photosensitive member 7, and around the electrophotographic photosensitive member 7,
A charging device 8, an exposure device 10, a developing device 11, a transfer device 12, a cleaning device 13, and a charge removing device 14 are sequentially arranged along the rotation direction of the electrophotographic photosensitive member 7. The charging device 8 is supplied with a potential from a power supply 9. Reference numeral 15 denotes a fixing device, and 19 denotes a transfer medium such as paper.

According to the electrophotographic apparatus, even when the electrophotographic photosensitive member 7 is repeatedly used, the generation of black spots is sufficiently prevented, and the deterioration of image quality is sufficiently prevented.

FIG. 9 is a schematic sectional view showing another embodiment of the electrophotographic apparatus of the present invention. The electrophotographic apparatus shown in FIG. 9 uses a contact charging device 8 as a charging device.
0 is different from the electrophotographic apparatus shown in FIG.

In the electrophotographic photoreceptor 7 of the present embodiment, the situation that the binder resin in the intermediate layer 2 is deteriorated by the metal oxide fine particles is sufficiently prevented, and the electrophotographic photoreceptor 7 is in a homogeneous state. The mold charging device 8 is provided, and even if a high electric field is repeatedly applied locally, the occurrence of pinholes is sufficiently prevented, the occurrence of black spots is sufficiently prevented, and the deterioration of image quality is also sufficiently prevented.

In the electrophotographic apparatus of this embodiment, since the contact-type charging device 8 is used, in addition to the advantage that the occurrence of defects on an image can be sufficiently prevented, a non-contact charging method such as a corona discharge method can be used. There is also an advantage that ozone is less likely to be generated as compared with the case where the charging device is used.

Note that the electrophotographic apparatus shown in FIGS.
Although the static eliminator 14 is provided, the electrophotographic apparatus of the present invention does not necessarily need to include the static eliminator.

Examples of the electrophotographic apparatus include a light lens type copying machine, a laser beam printer that emits near-infrared light or visible light, a digital copying machine, an LED printer, a laser facsimile, and the like.

Further, the electrophotographic apparatus can be used together with a one-component or two-component regular developer or a reversal developer.

Hereinafter, the contents of the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

[0133]

(Example 1) First, a diameter of 80 mm and a length of 340
An aluminum substrate having a thickness of 1 mm and a thickness of 1 mm was prepared.

On the other hand, a coating solution for forming an intermediate layer was prepared as follows. That is, 25 parts by weight of titanium oxide (trade name: TAF-J500 manufactured by Fuji Titanium Co., Ltd., no surface treatment, primary particle size: 50 nm) as metal oxide fine particles, and blocked isocyanate as a resin precursor (trade name: Sumitomo Bayern) 10 parts by weight of urethane (Sumidur 3175) and 60 parts by weight of methyl ethyl ketone are mixed for 30 minutes. Name: Tospearl 120 manufactured by Toshiba Silicone Co., Ltd.)
3 parts by weight, leveling agent (trade name: Silicone oil SH29PA manufactured by Dow Corning Toray Silicone Co., Ltd.) 0.0
1 part by weight was added, and the mixture was dispersed in a sand mill for 2 hours to obtain a coating liquid for forming an intermediate layer.

Next, the coating liquid for forming an intermediate layer was applied on the aluminum substrate by using a dip coating method, and dried and cured at 150 ° C. for 30 minutes to obtain a film having a thickness of 20 μm.
Was obtained.

Next, a charge generation layer was formed on the intermediate layer as follows. First, the Bragg angle (2θ ±) of the X-ray diffraction spectrum using Cukα ray as the charge generating substance
0.2 °) is at least 7.4 °, 16.6 °, 25.
15 parts by weight of gallium chloride phthalocyanine having diffraction peaks at positions of 5 ° and 28.3 °, and 10 parts by weight of a vinyl chloride-vinyl acetate copolymer resin (trade name: VMCH manufactured by Nippon Unicar) as a binder resin And 300 parts by weight of n-butyl alcohol were dispersed in a sand mill for 4 hours to obtain a dispersion for forming a charge generation layer. Then, the obtained dispersion for forming a charge generation layer was applied onto the intermediate layer by using a dip coating method and dried to obtain a charge generation layer having a thickness of 0.2 μm.

Next, a charge transport layer was formed on the charge generation layer. First, 4 parts by weight of N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1 '] biphenyl-4,4'-diamine and bisphenol Z polycarbonate resin (molecular weight 40,000) 6 Parts by weight were dissolved in 80 parts by weight of chlorobenzene to obtain a coating liquid for forming a charge transport layer. Then, the obtained coating solution for forming a charge transport layer is applied on the charge generation layer by using a dip coating method,
By drying in a minute, a charge transport layer having a thickness of 25 μm was obtained. Thus, an electrophotographic photosensitive member was obtained.

The obtained electrophotographic photosensitive member was used as a full-color printer having a contact-type charging device and an intermediate transfer device (product name: Docu Print C62 manufactured by Fuji Xerox Co., Ltd.).
0), and the print quality (initial print quality) was examined. Table 1 shows the results. As shown in Table 1, no black spots were observed, and good image quality was obtained.

[Table 1]

Further, a print test was continuously performed on 10,000 sheets while the electrophotographic photosensitive member was mounted on the full-color printer, and the print image quality of the 10,000th sheet was confirmed. Table 1 shows the results. As shown in Table 1, no black spots were observed, and no leak defects were observed. From this, it was found that the electrophotographic photoreceptor of the present invention exhibited excellent image quality maintenance.

(Example 2) An electrophotographic photosensitive member was obtained in the same manner as in Example 1, except that the intermediate layer was formed as follows.

That is, zinc oxide as a metal oxide fine particle (trade name: Nano Tek Zn manufactured by CI Kasei Co., Ltd.)
O, no surface treatment, primary particle size 30 nm) 33 parts by weight,
Blocked isocyanate as a resin precursor (trade name: Sumidur 317 manufactured by Sumitomo Bayern Urethane Co., Ltd.)
5) 30 parts by weight of 6 parts by weight and 25 parts by weight of methyl ethyl ketone
After mixing for 5 minutes, 5 parts by weight of a butyral resin (trade name: BM-1 manufactured by Sekisui Chemical Co., Ltd.) as a binder resin, 3 parts by weight of a silicone ball (trade name: Tospearl 120 manufactured by Toshiba Silicone Co., Ltd.), and a leveling agent ( Product name: Toray Dow Corning Silicone Silicone Oil SH29
PA) was added in an amount of 0.01 part by weight, and the mixture was dispersed in a sand mill for 2 hours to obtain a coating liquid for forming an intermediate layer. Then, the coating liquid for forming an intermediate layer is applied on an aluminum substrate having a diameter of 80 mm, a length of 340 mm, and a thickness of 1 mm by using a dip coating method, and dried and cured at 150 ° C. for 30 minutes. An intermediate layer of 20 μm was formed.

The print quality of the electrophotographic photosensitive member obtained as described above was evaluated in the same manner as in Example 1. Table 1 shows the results. As shown in Table 1, no black spots were observed in both the initial print quality and the print quality of the 10,000th print, and the print quality was good.

Example 3 Instead of 33 parts by weight of zinc oxide as metal oxide fine particles, tin oxide (trade name: S1, manufactured by Mitsubishi Materials Corporation, no surface treatment, primary particle size 20)
nm) An electrophotographic photosensitive member was obtained in the same manner as in Example 2 except that 40 parts by weight was used.

Example 1 of the obtained electrophotographic photosensitive member
The print quality was evaluated in the same manner as described above. Table 1 shows the results. As shown in Table 1, no black spots were observed in both the initial print quality and the print quality of the 10,000th print, and the print quality was good.

(Example 4) A melamine resin (trade name: Uban 20SE-60) as an inert resin was used in place of the blocked isocyanate, n-BuOH was used in place of methyl ethyl ketone, and the amount of butyral resin added was changed. An electrophotographic photosensitive member was obtained in the same manner as in Example 2, except that the amount was changed from 5 parts by weight to 6 parts by weight.

Example 1 of the obtained electrophotographic photosensitive member
The print quality was evaluated in the same manner as described above. Table 1 shows the results. As shown in Table 1, no black spots were observed in both the initial print quality and the print quality of the 10,000th print, and the print quality was good.

Example 5 Instead of 6 parts by weight of the blocked isoianate, 9 parts by weight of a phenol resin (trade name: J325 manufactured by Dainippon Ink and Chemicals, Inc.) was used as an inert resin, and 25 parts by weight of methyl ethyl ketone was used. An electrophotographic photoreceptor was obtained in the same manner as in Example 2, except that 5 parts by weight of methanol and 12 parts by weight of methoxypropanol were used, and the addition amount of butyral resin was changed from 5 parts by weight to 12 parts by weight.

Example 1 of the obtained electrophotographic photosensitive member
The print quality was evaluated in the same manner as described above. Table 1 shows the results. As shown in Table 1, no black spots were observed in both the initial print quality and the print quality of the 10,000th print, and the print quality was good.

(Comparative Example 1) Zinc oxide as a metal oxide fine particle (trade name: Nano Tek manufactured by C-I Kasei Co., Ltd.)
33 parts by weight of ZnO, no surface treatment, primary particle size of 30 nm) and butyral resin (trade name: BM-1 manufactured by Sekisui Chemical Co., Ltd.)
5 parts by weight and 35 parts by weight of methyl ethyl ketone were mixed by a sand mill for 30 minutes to obtain a dispersion.

The resulting dispersion was colored brown.
From this, it was found that butyral resin or methyl ethyl ketone was altered by zinc oxide.

Thereafter, 6 parts by weight of a blocked isocyanate (trade name: Sumidur 3175 manufactured by Sumitomo Bayer Urethane Co., Ltd.) was mixed with the dispersion, and the mixture was dispersed in a sand mill for 2 hours. Thereafter, 3 parts by weight of a silicone ball (trade name: Tospearl 120 manufactured by Toshiba Silicone Co., Ltd.) and 0.01 part by weight of a leveling agent (trade name: silicone oil SH29PA manufactured by Toray Dow Corning Silicone Co., Ltd.) are added and stirred to form an intermediate layer. A coating liquid for formation was obtained.

This intermediate layer-forming coating solution was applied on an aluminum substrate having a diameter of 80 mm, a length of 340 mm and a thickness of 1 mm by dip coating, and was applied at 150 ° C. and 30 ° C.
For 20 minutes to obtain an intermediate layer having a thickness of 20 μm.

Further, a charge generation layer and a charge transport layer were formed in the same manner as in Example 1 to obtain an electrophotographic photosensitive member.

Example 1 of the obtained electrophotographic photosensitive member
The print quality was evaluated in the same manner as described above. Table 1 shows the results. As shown in Table 1, when the print quality of the 10,000th print was examined, the occurrence of black spots was recognized. From this, it was found that the image quality was deteriorated by repeatedly using the electrophotographic photosensitive member.

Comparative Example 2 Titanium oxide as metal oxide particles (trade name: TAF-J50 manufactured by Fuji Titanium Industry Co., Ltd.)
0, no surface treatment, primary particle size 50 nm) 25 parts by weight,
Blocked isocyanate as a resin precursor (trade name: Sumidur 317 manufactured by Sumitomo Bayern Urethane Co., Ltd.)
5) 10 parts by weight, 9 parts by weight of butyral resin as a binder resin (trade name: BM-1 manufactured by Sekisui Chemical Co., Ltd.) and 60 parts by weight of methyl ethyl ketone were dispersed in a sand mill for 2 hours to obtain a dispersion. To this dispersion, 3 parts by weight of a silicone ball (trade name: Tospearl 120 manufactured by Toshiba Silicone Co., Ltd.) and 0.01 of a leveling agent (trade name: silicone oil SH29PA manufactured by Toray Dow Corning Silicone Co., Ltd.)
A part by weight was added and stirred to obtain a coating liquid for forming an intermediate layer. This intermediate layer forming coating solution was applied on an aluminum substrate having a diameter of 80 mm, a length of 340 mm, and a thickness of 1 mm by using a dip coating method, and was dried and cured at 150 ° C. for 30 minutes to obtain a 20 μm thick film. An intermediate layer was obtained.

Further, in the same manner as in Example 1, the charge generation layer
A charge transport layer was formed to obtain an electrophotographic photosensitive member.

Example 1 of the obtained electrophotographic photosensitive member
The print quality was evaluated in the same manner as described above. Table 1 shows the results. As shown in Table 1, when the print quality of the 10,000th print was examined, the occurrence of black spots was recognized. From this, it was found that the image quality was deteriorated by repeatedly using the electrophotographic photosensitive member.

From the results of Examples 1 to 5 and Comparative Examples 1 and 2, it was found that according to the present invention, the occurrence of black spots can be sufficiently prevented, and the deterioration of image quality can be sufficiently prevented. Further, from the results of Examples 1 to 5, it was found that according to the present invention, the maintainability of the image quality was also good.

[0159]

As described above, according to the electrophotographic photoreceptor of the present invention, deterioration of the binder resin is sufficiently prevented,
Since the intermediate layer is in a homogeneous state, generation of pinholes is sufficiently prevented even when a high electric field is applied. Therefore,
Generation of black spots due to repeated use of the electrophotographic photosensitive member is sufficiently prevented, and deterioration of image quality is sufficiently prevented.

Further, according to the method of manufacturing an electrophotographic photoreceptor of the present invention, a situation in which the binder resin is deteriorated by the metal oxide fine particles is sufficiently prevented, and a uniform state is obtained. Therefore, in the intermediate layer of the obtained electrophotographic photosensitive member, even when the electrophotographic photosensitive member is repeatedly used in the electrophotographic device having the contact-type charging device, the occurrence of pinholes is sufficiently prevented, and the occurrence of black spots is sufficiently prevented. And the deterioration of the image quality is sufficiently prevented. Further, according to this production method, the dispersion state of the metal oxide fine particles in the coating liquid for forming an intermediate layer is improved, so that the storage stability of the coating liquid for forming an intermediate layer is remarkably improved, and the image defect is improved. Is sufficiently prevented and an electrophotographic photosensitive member having a good resistance value is obtained.

Further, according to the electrophotographic process cartridge and the electrophotographic apparatus of the present invention, the binder resin is in a uniform state in the intermediate layer of the electrophotographic photosensitive member even when a contact-type charging device is used as the charging device. Therefore, even if the electrophotographic photosensitive member is used repeatedly, the occurrence of pinholes is sufficiently prevented, and the occurrence of black spots is sufficiently prevented. Therefore,
Image quality degradation can be sufficiently prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a first example of an electrophotographic photosensitive member having a single-layer structure.

FIG. 2 is a cross-sectional view illustrating a first example of an electrophotographic photosensitive member having a function-separated type laminated structure.

FIG. 3 is a cross-sectional view illustrating a second example of an electrophotographic photosensitive member having a single-layer structure.

FIG. 4 is a cross-sectional view illustrating a second example of an electrophotographic photosensitive member having a function-separated laminated structure.

FIG. 5 is a cross-sectional view showing a third example of the electrophotographic photosensitive member having a single-layer structure.

FIG. 6 is a cross-sectional view showing a third example of an electrophotographic photosensitive member having a function-separated type laminated structure.

FIG. 7 is a schematic sectional view showing an example of an electrophotographic apparatus provided with the electrophotographic process cartridge of the present invention.

FIG. 8 is a schematic sectional view showing an embodiment of the electrophotographic apparatus of the present invention.

FIG. 9 is a schematic sectional view showing another embodiment of the electrophotographic apparatus of the present invention.

DESCRIPTION OF SYMBOLS 1 ... conductive substrate, 2 ... intermediate layer, 3 ... photosensitive layer, 4 ... second intermediate layer, 5 ... protective layer, 7 ... electrophotographic photoreceptor, 8 ... contact type charging device, 9 ... Power supply, 10 ... Exposure device, 11 ... Developing device, 12 ... Transfer device, 13 ... Cleaning device, 14 ...
Static eliminator, 15: Fixing device, 16: Mounting rail, 19 ...
Transfer receiving medium, 31: charge generation layer, 32: charge transport layer.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masahiro Iwasaki 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Kazuo Yamazaki 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Michiko Aida 1600 Takematsu, Minami Ashigara, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Hiroshi Nakamura 1600 Takematsu, Minami Ashigara City, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. Address F-term in Fuji Xerox Co., Ltd. (reference) 2H068 AA43 AA45 EA13 FA27 FC01

Claims (6)

[Claims] 1. An electrophotographic photoreceptor having an intermediate layer between a conductive substrate and a photosensitive layer, wherein the intermediate layer is obtained by mixing fine metal oxide particles with a resin precursor and then dispersing the fine particles in a binder resin. An electrophotographic photoreceptor characterized by being formed using an intermediate layer forming coating solution obtained by the above. 2. An electrophotographic photoreceptor comprising an intermediate layer between a conductive substrate and a photosensitive layer, wherein the intermediate layer serves to inactivate metal oxide fine particles with respect to the metal oxide fine particles. An electrophotographic photoreceptor formed by using a coating liquid for forming an intermediate layer obtained by mixing with a resin and dispersing in a binder resin different from the inert resin. 3. A method of manufacturing an electrophotographic photoreceptor having an intermediate layer between a conductive substrate and a photosensitive layer, wherein the metal oxide fine particles are mixed with a resin precursor and then dispersed in a binder resin. Preparing a coating liquid for forming an intermediate layer, using the coating liquid for forming an intermediate layer, forming the intermediate layer on the conductive substrate, and forming a photosensitive layer on the intermediate layer; A method for producing an electrophotographic photoreceptor, comprising: 4. A method for producing an electrophotographic photoreceptor having an intermediate layer between a conductive substrate and a photosensitive layer, wherein the metal oxide fine particles are mixed with an inert resin inert to the metal oxide fine particles. After mixing, the mixture is dispersed in a binder resin different from the inert resin to prepare a coating solution for forming an intermediate layer, and using the coating solution for forming an intermediate layer, the intermediate layer is formed on the conductive substrate. And a step of forming a photosensitive layer on the intermediate layer. 5. An electrophotographic apparatus main body comprising: the electrophotographic photosensitive member according to claim 1; and a contact-type charging device that contacts the surface of the electrophotographic photosensitive member to charge the surface. An electrophotographic process cartridge, which is detachable from the electrophotographic process cartridge. 6. An electrophotographic photoreceptor according to claim 1 or 2, a contact-type charging device that contacts the surface of the electrophotographic photoreceptor to charge the surface, and exposes the surface of the electrophotographic photoreceptor. An electrophotographic apparatus, comprising: an exposure device that forms an electrostatic latent image by performing a developing process; a developing device that develops the electrostatic latent image; and a transfer device that transfers the developed image to a transfer-receiving medium. .