JP2006047870A - Electrophotographic photoreceptor and manufacturing method therefor, electrophotographic apparatus, and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor in which leakage preventiveness and electrical characteristics are made compatible with each other at a high level and satisfactory image quality can be obtained without the occurrence of an image quality defect, such as fogging, when the photoreceptor is used together with a contact electrifying apparatus, and to provided a manufacturing method therefor, and a process cartridge and electrophotographic apparatus each using the electrophotographic photoreceptor. <P>SOLUTION: The electrophotographic photoreceptor 1 is equipped with an intermediate layer 4 between a conductive substrate 2 and a photosensitive layer 3, wherein the intermediate layer 4 contains an ionic liquid which is liquid at room temperature and a binder resin for holding the ionic liquid into the intermediate layer 4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electrophotographic photosensitive member used for electrophotographic image formation, a method for manufacturing the same, an electrophotographic apparatus, and a process cartridge.

  The electrophotographic system is widely used in the fields of copiers, laser printers, and the like because high-speed image formation is possible and high-quality images can be obtained.

  As an electrophotographic photoreceptor (hereinafter, simply referred to as “photoreceptor” in some cases) used for electrophotographic image formation, most organic photoreceptors using a photoconductive organic material are used. Further, as the organic photoreceptor, a function-separated type photoreceptor provided with a multilayered photosensitive layer including a charge generation layer and a charge transport layer is mainly used. There is also known a photoreceptor in which an intermediate layer (undercoat layer) is provided between the photosensitive layer and a conductive substrate that supports the photosensitive layer.

  Since such a photoreceptor is usually repeatedly used in an image forming process including steps such as charging, exposure, development, and transfer, the photoreceptor exhibits stable characteristics even after repeated use (hereinafter referred to as “repetition”). Called "stability"). In addition, the photoreceptor is required to be hardly affected by temperature and humidity (hereinafter referred to as “environmental stability”).

  Many of these characteristics depend not only on the photosensitive layer (charge generation layer, charge transport layer, etc.) but also on the intermediate layer. In particular, in order to obtain repeated stability, the intermediate layer has a low charge accumulation property due to repeated use. It is important to provide Also, the intermediate layer plays a major role in preventing image quality defects, and the undercoat layer is used to suppress image quality defects caused by defects or stains in the conductive substrate, coating film defects such as charge generation layers, or coating film irregularities. Has become an indispensable existence.

  By the way, in recent years, as a charging device for an electrophotographic apparatus, a contact charging type charging device such as a charging roll has been used instead of a non-contact type charging device such as a corotron. The contact charging device has an advantage that generation of ozone can be suppressed. However, when the contact charging device is used, the charged state of the photoconductor tends to be non-uniform. Further, if a local deteriorated portion is present in the photoconductor, a local high electric field is applied to the deteriorated portion during contact charging to generate an electrical pinhole, which is liable to cause an image quality defect. This pinhole leak may occur due to coating film defects in the photosensitive layer, but in addition to this, conductive foreign matter (carbon fiber, carrier powder, etc.) generated from within the electrophotographic apparatus may come into contact with the photosensitive member. This may occur because it is easy to form a conductive path between the contact charging device and the photosensitive substrate by penetrating into the photosensitive member.

Therefore, in order to avoid the above-described phenomenon associated with the use of the contact charging device, studies have been made on the constituent materials and physical properties of the intermediate layer, and electrophotographic photoreceptors having various undercoat layers have been proposed.
For example, Patent Document 1 below discloses an organic photoreceptor including an undercoat layer that includes a binder resin, a charge transport material, and conductive fine powder.
Japanese Patent Laid-Open No. 1-113758

  However, even with the above-described conventional electrophotographic photosensitive member, it has been very difficult to obtain sufficient image quality when used with a contact charging device. More specifically, it is desirable that the thickness of the undercoat layer is large (for example, about 10 to 30 μm) from the viewpoint of charge leakage prevention due to the occurrence of pinholes (hereinafter simply referred to as “leak prevention”). However, in order to obtain sufficient electrical characteristics, the resistance must be reduced as the thickness of the undercoat layer increases. Therefore, in the photoreceptor having such a thick film and reduced resistance, the blocking property for preventing the injection of charges from the substrate to the photosensitive layer is weakened, and fog is likely to occur.

  Furthermore, in the conventional electrophotographic photosensitive member, by providing the undercoat layer with the above-described configuration, the undercoat layer is provided with a blocking function and a resistance adjusting function. It is difficult from the viewpoint of production to stably reproduce a dispersed state that relies largely on the dispersed state of the conductive powder in the undercoat layer and achieves both functions.

  The present invention has been made in view of the above-described problems of the prior art, and has a high level of both anti-leakage properties and electrical characteristics. Even when used with a contact charging device, image quality such as fogging is achieved. An object of the present invention is to provide an electrophotographic photosensitive member capable of obtaining good image quality without causing defects, a manufacturing method thereof, a process cartridge and an electrophotographic apparatus using the electrophotographic photosensitive member.

  Therefore, in order to solve the above-described problems, the electrophotographic photoreceptor of the present invention includes a conductive substrate, an intermediate layer provided on the conductive substrate, and a photosensitive layer provided on the intermediate layer. The intermediate layer contains an ionic liquid and a binder resin for holding the ionic liquid in the intermediate layer.

  Here, the “ionic liquid” in the present invention refers to a substance that is liquid at room temperature (for example, 25 ° C.) and exhibits ionicity. The ionic liquid according to the present invention includes so-called onium salts and compounds having a structure in which an anionic substituent is bonded to a cation constituent atom, as will be described later.

  According to the electrophotographic photosensitive member of the present invention, the intermediate layer is provided between the conductive substrate and the photosensitive layer, and the intermediate layer contains an ionic liquid and a binder resin, thereby preventing the leakage of the intermediate layer. Since both the electrical characteristics are sufficiently enhanced, it is possible to obtain a good image quality without causing image quality defects such as fog even when used with a contact charging device.

  The reason why the above-described effect can be obtained by the present invention is not necessarily clear, but the present inventor presumes as follows. That is, in the conventional electrophotographic photoreceptor, in the case of an intermediate layer based on ionic conduction, the residual potential tends to increase when the film thickness is increased in order to improve leakage prevention, and the conductive component is utilized. In the case of an intermediate layer based on electron conduction, as described above, there is a problem that it is subjected to stability in manufacturing, and in both cases, it is difficult to achieve both leakage prevention properties and electrical characteristics. On the other hand, in the present invention, attention is paid to the ionic liquid. However, in the case of a normal ionic compound (salt), a solid conductive material is included in the intermediate layer, and the degree of freedom of the conductive material in the intermediate layer. Therefore, the conductive material cannot function effectively when an electric field is applied. On the other hand, in the electrophotographic photosensitive member of the present invention, the ionic liquid as the conductive substance has a predetermined degree of freedom by holding the ionic liquid in the intermediate layer, and the binder resin is used. It is considered that the ionic liquid can be ionized or take a predetermined orientation when an electric field is applied to the intermediate layer because it is sufficiently uniformly held in the intermediate layer. Therefore, in the present invention, the inventor speculates that it is not necessary to reduce the resistance as the film thickness is increased, and that both the leak prevention property and the electrical characteristics can be achieved at a high level.

In the present invention, the ionic liquid is preferably at least one selected from compounds represented by the following general formulas (1) to (8). By using these ionic liquids, it is possible to effectively realize an electrophotographic photoreceptor in which leakage prevention properties and electrical characteristics are compatible at a high level. Here, the compounds represented by the general formulas (1) to (4) are so-called onium salts, and when an electric field is applied to the intermediate layer, these onium salts are ionized in the intermediate layer and are high in the intermediate layer. It is thought to impart conductivity. On the other hand, the general formula (5) compounds represented by - (8), a cation, a monovalent substituent containing an anionic -A ^- those having a bond structure, an electric field is applied to the intermediate layer It is considered that these compounds are oriented in a predetermined direction in the intermediate layer and impart high conductivity to the intermediate layer.

[Wherein, R ¹ represents a group of carbon atoms having 2 to 10 carbon atoms constituting a ring together with N ⁺ , and R ² is a chain carbonization of 1 to 8 carbon atoms which may contain a hydrogen atom or a heteroatom. Represents a hydrogen group, X ⁻ represents an anion, p represents 1 or 2, p is 1 when the bond between N ⁺ and another atom contains one double bond, N ⁺ and other When all the bonds with the atoms are single bonds, p is 2. When p is 2, two R ^{2 s} may be the same or different. ]

[Wherein R ³ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with C, N ⁺ and N, and R ⁴ , R ⁵ and R ⁶ may be the same or different, and each represents a hydrogen atom, Alternatively, it represents a C 1-8 chain hydrocarbon group which may contain a hetero atom, and X ⁻ represents an anion. ]

[Wherein, R ⁷ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with N ⁺ , C and N, and R ⁸ and R ⁹ may be the same or different, and each represents a hydrogen atom or a heteroatom. the represents comprise also a good C1-8 chain hydrocarbon group, X ^- represents an anion. ]

[Wherein, Q represents a nitrogen atom, a phosphorus atom or a sulfur atom, and R ¹⁰ , R ¹¹ , R ¹² and R ¹³ may be the same or different and each may contain a hydrogen atom or a hetero atom. Represents a good chain hydrocarbon group having 1 to 8 carbon atoms, X- represents an anion, q represents 0 or 1, q is 0 when Q is a sulfur atom, and Q is a nitrogen atom or a phosphorus atom. When q is 1. ]

[Wherein, R ¹⁴ represents a group of carbon atoms having 2 to 10 carbon atoms constituting a ring together with N ⁺ , and R ¹⁵ is a chain carbonization of 1 to 8 carbon atoms which may contain a hydrogen atom or a heteroatom. A represents a hydrogen group, A represents a monovalent substituent having an anionic property, r represents an integer of 0 to 2, a bond between N ⁺ and another atom contains one double bond, and N ^{When +} and A ⁻ are bonded, r is 0, and when the bond between N ⁺ and another atom includes one double bond or when N ⁺ and A ⁻ are not bonded r is 1, r is 2 when the bonds of N ⁺ and other atoms are all single bonds, and N + and A ⁻ are not bonded, and when R is 2, two R ² are It may be the same or different. ]

[Wherein R ¹⁶ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with C, N ⁺ and N, and R ¹⁷ and R ¹⁸ may be the same or different, and each represents a hydrogen atom or a heteroatom. Represents a chain hydrocarbon group having 1 to 8 carbon atoms which may contain A, and A represents a monovalent substituent having anionic property. ]

[Wherein R ¹⁹ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with N ⁺ , C and N, and R ²⁰ is a hydrogen atom or a C ¹ to C 8 which may contain a hetero atom. Represents a chain hydrocarbon group, and A represents a monovalent substituent having an anionic property. ]

[Wherein, Q represents a nitrogen atom, a phosphorus atom or a sulfur atom, and R ²¹ , R ²² and R ²³ may be the same or different and each may contain a hydrogen atom or a hetero atom. 1 to 8 chain hydrocarbon group, A represents a monovalent substituent having an anionic property, t represents 0 or 1, t is 0 when Q is a sulfur atom, and Q is a nitrogen atom Or t is 1 when it is a phosphorus atom. ]
Among the ionic liquids represented by the general formulas (1) to (8), the ionic liquid is represented by the general formula (2) or (6), and R ³ , C, N ⁺ and N in the formula In particular, an ionic liquid in which the ring constituted by or a ring constituted by R ¹⁶ , C, N ⁺ and N is one selected from an imidazole ring, a 2-imidazoline ring, a tetrahydropyrimidine ring, a diazabicyclo ring and a pyridine ring preferable.

The electrophotographic photosensitive member of the present invention may be characterized in that the film thickness of the intermediate layer is 15 μm or more and the volume resistivity of the intermediate layer is 1 × 10 ⁷ to 1 × 10 ¹³ Ω · cm. . In the present invention, since the intermediate layer is formed using the ionic liquid as described above, the film thickness and the volume resistivity of the intermediate layer can be respectively set as described above, and the leakage prevention property and electrical characteristics can be improved. It is possible to effectively realize an electrophotographic photoreceptor in which both are compatible at a high level.

  The method for producing an electrophotographic photoreceptor of the present invention includes an electrophotographic photoreceptor comprising a conductive substrate, an intermediate layer provided on the conductive substrate, and a photosensitive layer provided on the intermediate layer. A method for producing an intermediate layer-forming coating liquid by adding an ionic liquid that is liquid at room temperature and a binder resin or a precursor thereof to a predetermined solvent and dissolving, emulsifying or dispersing the manufacturing method Applying a coating solution for forming an intermediate layer onto a conductive substrate and drying to form an intermediate layer containing an ionic liquid and a binder resin; and applying the coating solution for forming a photosensitive layer to the intermediate layer And a step of forming a photosensitive layer by applying the coating on the substrate and drying it.

  According to the production method of the present invention, the electrophotographic photosensitive member of the present invention in which leakage prevention properties and electrical characteristics are compatible at a high level can be easily and reliably obtained by having the above configuration.

  The electrophotographic apparatus of the present invention includes the electrophotographic photosensitive member of the present invention, a charging device for charging the electrophotographic photosensitive member, and an exposure device for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image. And a developing device that develops the electrostatic latent image to form a toner image, and a transfer device that transfers the toner image from the electrophotographic photosensitive member to a transfer medium.

  The process cartridge of the present invention includes the electrophotographic photosensitive member of the present invention, a charging device that charges the electrophotographic photosensitive member, a developing device that develops an electrostatic latent image formed by exposure and forms a toner image, And at least one selected from a cleaning device that removes toner remaining on the electrophotographic photosensitive member after transfer.

  According to the electrophotographic apparatus and the process cartridge of the present invention, an electrophotographic process including charging, exposure, development, and transfer is performed using the electrophotographic photosensitive member of the present invention without causing image quality defects such as fog. Good image quality can be obtained. In the electrophotographic apparatus and the process cartridge of the present invention, both the anti-leakage property and the electrical characteristics are imparted to the electrophotographic photosensitive member. Therefore, charging is performed using a contact charging type charging device. However, the above effect can be obtained effectively.

  According to the present invention, leak prevention and electrical characteristics are compatible at a high level, and even when used with a contact charging device, good image quality can be obtained without causing image quality defects such as fog. It is possible to provide a possible electrophotographic photosensitive member and a method for producing the same, and a process cartridge and an electrophotographic apparatus using the electrophotographic photosensitive member.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as the case may be. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic sectional view showing a preferred embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 1 shown in FIG. 1 is a function-separated photoreceptor in which a charge generation layer 5 and a charge transport layer 6 are separately provided, and an intermediate layer (undercoat) is formed on one side of the conductive substrate 2. Layer) 4, charge generation layer 5 and charge transport layer 6 are laminated in this order.

  As the conductive substrate 2, for example, metals such as aluminum, nickel, chromium, and stainless steel, and thin films such as aluminum, titanium, nickel, chromium, stainless steel, gold, vanadium, tin oxide, indium oxide, and ITO are provided. Plastic film or the like, or paper coated with or impregnated with a conductivity-imparting agent, plastic film, and the like can be raised.

  The shape of the conductive substrate 2 may be a drum shape, a sheet shape, or a plate shape. When a metal pipe is used as the conductive substrate, the metal pipe may be left as it is, or a surface such as mirror cutting, etching, anodizing, rough cutting, centerless grinding, sand blasting, wet honing, etc. It may be given to.

  The intermediate layer 4 is a layer that includes an ionic liquid and a binder resin.

  The ionic liquid is not particularly limited as long as it is liquid at room temperature and can be ionized into a cation and an anion, but at least one selected from compounds represented by the following general formulas (1) to (8) It is preferable that

[Wherein, R ¹ represents a group of carbon atoms having 2 to 10 carbon atoms constituting a ring together with N ⁺ , and R ² is a chain carbonization of 1 to 8 carbon atoms which may contain a hydrogen atom or a heteroatom. Represents a hydrogen group, X ⁻ represents an anion, p represents 1 or 2, p is 1 when the bond between N ⁺ and another atom contains one double bond, N ⁺ and other When all the bonds with the atoms are single bonds, p is 2. When p is 2, two R ^{2 s} may be the same or different. ]

[Wherein R ³ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with C, N ⁺ and N, and R ⁴ , R ⁵ and R ⁶ may be the same or different, and each represents a hydrogen atom, Alternatively, it represents a C 1-8 chain hydrocarbon group which may contain a hetero atom, and X ⁻ represents an anion. ]

[Wherein, R ⁷ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with N ⁺ , C and N, and R ⁸ and R ⁹ may be the same or different, and each represents a hydrogen atom or a heteroatom. the represents comprise also a good C1-8 chain hydrocarbon group, X ^- represents an anion. ]

[Wherein, Q represents a nitrogen atom, a phosphorus atom or a sulfur atom, and R ¹⁰ , R ¹¹ , R ¹² and R ¹³ may be the same or different and each may contain a hydrogen atom or a hetero atom. Represents a good chain hydrocarbon group having 1 to 8 carbon atoms, X- represents an anion, q represents 0 or 1, q is 0 when Q is a sulfur atom, and Q is a nitrogen atom or a phosphorus atom. When q is 1. ]

[Wherein, R ¹⁴ represents a group of carbon atoms having 2 to 10 carbon atoms constituting a ring together with N ⁺ , and R ¹⁵ is a chain carbonization of 1 to 8 carbon atoms which may contain a hydrogen atom or a heteroatom. A represents a hydrogen group, A represents a monovalent substituent having an anionic property, r represents an integer of 0 to 2, a bond between N ⁺ and another atom contains one double bond, and N ^{When +} and A ⁻ are bonded, r is 0, and when the bond between N ⁺ and another atom includes one double bond or when N ⁺ and A ⁻ are not bonded r is 1, r is 2 when the bonds of N ⁺ and other atoms are all single bonds, and N + and A ⁻ are not bonded, and when R is 2, two R ² are It may be the same or different. ]

[Wherein R ¹⁶ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with C, N ⁺ and N, and R ¹⁷ and R ¹⁸ may be the same or different, and each represents a hydrogen atom or a heteroatom. Represents a chain hydrocarbon group having 1 to 8 carbon atoms which may contain A, and A represents a monovalent substituent having anionic property. ]

[Wherein R ¹⁹ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with N ⁺ , C and N, and R ²⁰ is a hydrogen atom or a C ¹ to C 8 which may contain a hetero atom. Represents a chain hydrocarbon group, and A represents a monovalent substituent having an anionic property. ]

[Wherein, Q represents a nitrogen atom, a phosphorus atom or a sulfur atom, and R ²¹ , R ²² and R ²³ may be the same or different and each may contain a hydrogen atom or a hetero atom. 1 to 8 chain hydrocarbon group, A represents a monovalent substituent having an anionic property, t represents 0 or 1, t is 0 when Q is a sulfur atom, and Q is a nitrogen atom Or t is 1 when it is a phosphorus atom. ]
The compounds represented by the general formulas (1) to (4) are so-called onium salts. In such an onium salt, X ⁻ which is an anion is not particularly limited, but is selected from iodine ion, nitric acid, perchloric acid, tetrafluoroboric acid, hexafluoroboric acid, trifluoromethanesulfonic acid, trifluoroacetic acid and alkylcarboxylic acid. It is preferable that it is at least one kind. Thereby, the volume resistance of the intermediate | middle layer 4 can be controlled more accurately, and both leak prevention property and an electrical property can be improved further.

  Among the onium salts, the onium salts represented by the general formulas (1) to (3) include a cation having a ring structure. As the cation having a ring structure, a cation having a ring selected from an imidazole ring, an imidazoline ring, a pyrazole ring, a pyrazoline ring, a tetrahydropyrimidine ring, a diazabicyclo ring, and a pyridine ring is preferable. For example, as a cation having an imidazole ring, 1,3-dialkyldialkylimidazolium, 1,2,3-trialkylimidazolium and the like can be mentioned. Moreover, 1-methyl pyrazolium etc. are mentioned as a cation which has a pyrazole ring. Moreover, butyl pyridinium etc. are mentioned as a cation which has a pyridine ring.

On the other hand, the general formula (5) compounds represented by - (8), a cation, a monovalent substituent -A having anionic ^- those having bound structure. -A ^- as has anionic, and the general formula (5) to (7) is not particularly limited as long as the constituent atom or the general formula ring (8) and Q ⁺ being couplable in However, the substituent represented by the following general formula (i) is preferable.

^{_{- (B) n -D - (}} i)
In general formula (i), B represents a divalent group, preferably a linear or branched alkylene group having 1 to 10 carbon atoms. Further, -D ^- -SO ₃ represents a monovalent anionic group, preferably ^-, -COO - is C = C (CN) _2, etc. ^-, -O (O). Moreover, n shows the integer of 0-4.

  The compounds represented by the general formulas (5) to (7) include a cation having a ring structure. As the cation having a ring structure, as in the case of the onium salts represented by the general formulas (1) to (3), an imidazole ring, an imidazoline ring, a pyrazole ring, a pyrazoline ring, a tetrahydropyrimidine ring, a diazabicyclo ring, and a pyridine A cation having a ring selected from rings is preferred.

Preferred examples of the compounds represented by the general formulas (5) to (8) are shown in Table 1 below.

  In the present invention, one of the above ionic liquids may be used alone, or two or more may be used in combination, but the compound represented by the general formula (6) is essential. It is preferable to make it contain in the intermediate | middle layer 4 as a component.

  The content of the ionic liquid in the intermediate layer 4 is preferably 0.01 to 90% by mass, more preferably 1.0 to 10% by mass, based on the total amount of the constituent materials of the intermediate layer 4.

  The binder resin used for the intermediate layer 4 is not particularly limited as long as it can hold the ionic liquid in the intermediate layer 4. Specifically, polyolefin resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinyl acetal resin, polyvinyl acetate resin, polyvinyl alcohol resin, polyether resin, polyamide resin, cellulose resin, polyester resin, polycarbonate resin, etc. can be used. It is. Alternatively, a charge transporting resin having a charge transporting group or a conductive resin such as polyaniline may be used. These binder resins may be used as a mixture of one or more selected from one.

  Further, a resin obtained by using a resin precursor such as an isocyanate compound, an epoxy group-containing prepolymer, a phenol compound, a methylol compound, a melamine compound, an unsaturated polyester, diallyl phthalate, or an imide group-containing prepolymer is bonded to the intermediate layer 4. It is good also as a resin.

  Here, when block type polyisocyanate is used as the resin precursor, alcohol compounds, phenol compounds, lactam compounds, amine compounds, amide compounds, oxime compounds, β-diketone compounds, and the like can be used as the blocking agent.

  Further, a burette-modified product of hexamethylene diisocyanate, an isocyanurate-modified product of hexamethylene diisocyanate, a burette-modified product of isophorone diisocyanate, an isocyanurate-modified product of isophorone diisocyanate may be used.

  The content of the binder resin in the intermediate layer 4 is preferably 10 to 99% by mass, more preferably 90 to 99% by mass, based on the total amount of the constituent materials of the intermediate layer 4.

  The intermediate layer 4 can be formed using a coating solution in which the ionic liquid and the binder resin or resin precursor are added to a predetermined solvent and dissolved, emulsified or dispersed.

  Examples of the solvent used for the intermediate layer forming coating solution include aromatic hydrocarbon solvents such as toluene and chlorobenzene, and aliphatic alcohol solvents such as methanol, ethanol, n-propanol, iso-propanol, and n-butanol. , Ketone solvents such as acetone, cyclopentanone, cyclohexanone, 2-butanone, halogenated aliphatic hydrocarbon solvents such as methylene chloride, chloroform, ethylene chloride, cyclic or linear such as tetrahydrofuran, dioxane, ethylene glycol, diethyl ether And ether solvents such as methyl ether solvent, methyl acetate, ethyl acetate and n-butyl acetate. These solvents can be used alone or in combination of two or more.

  In addition, as a method of applying the intermediate layer forming coating solution onto the conductive substrate 2, dip coating method, push-up coating method, wire bar coating method, spray coating method, blade coating method, knife coating method, curtain coating method, etc. Is mentioned.

The film thickness of the intermediate layer 4 thus formed is preferably 15 μm or more, and more preferably 20 μm or more and 50 μm or less. Further, the volume resistivity of the intermediate layer 4 is preferably 1 × 10 ⁷ to 1 × 10 ¹³ Ω · cm.

  Further, in order to prevent the moire image, when the exposure laser wavelength used is λ, the surface roughness of the intermediate layer 4 can be adjusted to λ · ¼n (n is the refractive index of the upper layer) to λ. preferable. Examples of means for adjusting the surface roughness include addition of resin particles to the intermediate layer 4 and polishing of the intermediate layer 4. As the resin particles, silicone resin particles, cross-linked PMMA resin particles, and the like can be used. Examples of the polishing method include buffing, sandblasting, wet honing, and grinding.

  The intermediate layer 4 may further contain metal oxide fine particles in order to adjust the conductivity. Specific preferred examples of the metal oxide fine particles include tin oxide, titanium oxide, zinc oxide, aluminum oxide and the like. These metal oxide fine particles may be used alone or in a combination of two or more. Moreover, powder resistance and dispersibility can be controlled by performing surface treatment with a coupling agent on the metal oxide fine particles.

  Further, the intermediate layer 4 can use various additives for improving electrical characteristics, improving environmental stability, and improving image quality. Specific examples of additives include quinone compounds such as chloranylquinone, bromoanilquinone, anthraquinone, tetracyanoquinodimethane compounds, 2,4,7-trinitrofluorenone, 2,4,5,7- Fluorenone compounds such as tetranitro-9-fluorenone, 2- (4-biphenyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole and 2,5-bis (4-naphthyl)- Oxadiazole compounds such as 1,3,4-oxadiazole, 2,5-bis (4-diethylaminophenyl) 1,3,4-oxadiazole, xanthone compounds, thiophene compounds, 3,3 ′, Electron transporting substances such as diphenoquinone compounds such as 5,5′-tetra-t-butyldiphenoquinone, electron transporting pigments such as polycyclic condensation systems and azo systems, Hexafluorophosphate chelate compounds, titanium chelate compounds, aluminum chelate compounds, titanium alkoxide compounds, organic titanium compounds, there can be used a known material such as a silane coupling agent. These compounds can be used alone or as a mixture or polycondensate of a plurality of compounds.

  The charge generation layer 5 includes a charge generation material and a binder resin. As the charge generation material, phthalocyanine pigments such as metal-free phthalocyanine, chlorogallium phthalocyanine, hydroxygallium phthalocyanine, dichlorotin phthalocyanine, and titanyl phthalocyanine can be used. ) Chlorogallium phthalocyanine crystal having strong diffraction peaks at least at 7.4 °, 16.6 °, 25.5 ° and 28.3 °, at least a Bragg angle (2θ ± 0.2 °) with respect to CuKα characteristic X-rays Metal-free phthalocyanine crystals having strong diffraction peaks at 7.7 °, 9.3 °, 16.9 °, 17.5 °, 22.4 °, and 28.8 °, Bragg angle (2θ ± 0.2 °) at least 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 ° Hydroxygallium phthalocyanine crystals having strong diffraction peaks at 25.1 ° and 28.3 °, Bragg angles (2θ ± 0.2 °) with respect to CuKα characteristic X-rays of at least 9.6 °, 24.1 ° and 27.2 A titanyl phthalocyanine crystal having a strong diffraction peak at 0 ° can be used. In addition, as the charge generation material, a quinone pigment, a perylene pigment, an indigo pigment, a bisbenzimidazole pigment, an anthrone pigment, a quinacridone pigment, and the like can be used. These charge generation materials can be used alone or in admixture of two or more.

  Examples of the binder resin in the charge generation layer 5 include polycarbonate resin such as bisphenol A type or bisphenol Z type, acrylic resin, methacrylic resin, polyarylate resin, polyester resin, polyvinyl chloride resin, polystyrene resin, and acrylonitrile-styrene. Polymer resin, acrylonitrile-butadiene copolymer, polyvinyl acetate resin, polyvinyl formal resin, polysulfone resin, styrene-butadiene copolymer resin, vinylidene chloride-acrylonitrile copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride resin Silicone resin, phenol-formaldehyde resin, polyacrylamide resin, polyamide resin, poly-N-vinylcarbazole resin, and the like can be used. These binder resins can be used alone or in combination of two or more. The mixing ratio of the charge generating material and the binder resin is preferably in the range of 10: 1 to 1:10.

  The charge generation layer 5 can be formed using a coating solution obtained by adding the above constituent materials to a predetermined solvent. Examples of the solvent used in the coating solution for forming the charge generation layer include aromatic hydrocarbon solvents such as toluene and chlorobenzene, and aliphatic alcohols such as methanol, ethanol, n-propanol, iso-propanol, and n-butanol. Solvents, ketone solvents such as acetone, cyclohexanone and 2-butanone, halogenated aliphatic hydrocarbon solvents such as methylene chloride, chloroform and ethylene chloride, cyclic or linear ether systems such as tetrahydrofuran, dioxane, ethylene glycol and diethyl ether Examples of the solvent include ester solvents such as methyl acetate, ethyl acetate, and n-butyl acetate. These solvents can be used alone or in combination of two or more.

  In order to enhance the dispersibility of the charge generation material in the charge generation layer 5, it is preferable to perform a dispersion treatment on the charge generation layer forming coating solution. As a dispersion treatment method, a media disperser such as a ball mill, a vibration ball mill, an attritor, a sand mill, or a horizontal sand mill, or a medialess disperser such as an agitator, an ultrasonic disperser, a roll mill, or a high-pressure homogenizer can be used. Further, examples of the high-pressure homogenizer include a collision method in which the dispersion liquid is dispersed by liquid-liquid collision or liquid-wall collision in a high pressure state, and a penetration method in which the fine liquid is penetrated and dispersed in a high pressure state.

  The charge generation layer 5 can be formed by applying the coating solution for forming the charge generation layer thus obtained on the intermediate layer 4 and drying it. As the coating method, usual methods such as a dip coating method, a push-up coating method, a wire bar coating method, a spray coating method, a blade coating method, a knife coating method, and a curtain coating method can be used. The thickness of the charge generation layer is generally set in the range of 0.01 to 5 μm, preferably 0.05 to 2.0 μm.

  The charge transport layer 6 includes a charge transport material and a binder resin. Examples of the charge transport material include oxadiazole derivatives such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole, 1,3,5-triphenyl-pyrazoline, 1- [ Pyrazoline derivatives such as pyridyl- (2)]-3- (p-diethylaminostyryl) -5- (p-diethylaminostyryl) pyrazoline, triphenylamine, N, N′-bis (3,4-dimethylphenyl) biphenyl- Aromatic tertiary amino compounds such as 4-amine, tri (p-methylphenyl) aminyl-4-amine, dibenzylaniline, N, N′-bis (3-methylphenyl) -N, N′-diphenylbenzidine Aromatic tertiary diamino compounds such as 3- (4′-dimethylaminophenyl) -5,6-di- (4′-methoxyphenyl) -1,2,4 1,2,4-triazine derivatives such as triazine, hydrazone derivatives such as 4-diethylaminobenzaldehyde-1,1-diphenylhydrazone, quinazoline derivatives such as 2-phenyl-4-styryl-quinazoline, 6-hydroxy-2,3- Benzofuran derivatives such as di (p-methoxyphenyl) benzofuran, α-stilbene derivatives such as p- (2,2-diphenylvinyl) -N, N-diphenylaniline, enamine derivatives, carbazole derivatives such as N-ethylcarbazole, poly -Hole transport materials such as -N-vinylcarbazole and its derivatives, quinone compounds such as chloranil and broanthraquinone, tetraanoquinodimethane compounds, 2,4,7-trinitrofluorenone, 2,4,5,7 -Fluorenone such as tetranitro-9-fluorenone Examples thereof include electron transport materials such as compounds, xanthone compounds, and thiophene compounds, and polymers having groups composed of the above-described compounds in the main chain or side chain. These charge transport materials can be used alone or in combination of two or more.

  Examples of the binder resin in the charge transport layer 6 include polycarbonate resin such as bisphenol A type or bisphenol Z type, acrylic resin, methacrylic resin, polyarylate resin, polyester resin, polyvinyl chloride resin, polystyrene resin, acrylonitrile- Styrene copolymer resin, acrylonitrile-butadiene copolymer resin, polyvinyl acetate resin, polyvinyl formal resin, polysulfone resin, styrene-butadiene copolymer resin, vinylidene chloride-acrylonitrile copolymer resin, vinyl chloride-vinyl acetate-anhydrous Insulating resins such as maleic acid resin, silicone resin, phenol-formaldehyde resin, polyacrylamide resin, polyamide resin, chlorine rubber, and polyvinylcarbazole, polyvinyl alcohol Anthracene, organic photoconductive polymers such as polyvinyl pyrene, and the like. These binder resins can be used individually by 1 type or in mixture of 2 or more types.

  The charge transport layer 6 can be formed using a coating liquid for forming a charge transport layer in which the above-described constituent materials are added to a predetermined solvent. Examples of the solvent used for forming the charge transport layer 6 include aromatic hydrocarbon solvents such as toluene and chlorobenzene, and aliphatic alcohol solvents such as methanol, ethanol, n-propanol, iso-propanol, and n-butanol. , Ketone solvents such as acetone, cyclohexanone and 2-butanone, halogenated aliphatic hydrocarbon solvents such as methylene chloride, chloroform and ethylene chloride, and cyclic or linear ether solvents such as tetrahydrofuran, dioxane, ethylene glycol and diethyl ether And ester solvents such as methyl acetate, ethyl acetate, and n-butyl acetate. These solvents can be used alone or in combination of two or more. The blending ratio of the charge transport material and the binder resin is preferably 10: 1 to 1: 5.

  The charge transport layer forming coating solution may be applied onto the charge generation layer 5 by dip coating, push-up coating, wire bar coating, spray coating, blade coating, knife coating, curtain coating. A usual method such as can be used.

  The film thickness of the charge transport layer 6 thus formed is preferably set in the range of 5 to 50 μm, more preferably 10 to 40 μm.

  In the case where the charge transport layer 6 is a surface layer (a layer disposed farthest from the conductive substrate 2) as in the electrophotographic photosensitive member 1 shown in FIG. In order to improve the properties and toner cleaning properties, fluorine-based resin particles may be contained. Examples of fluorine resin particles include tetrafluoroethylene resin, trifluorinated ethylene resin, hexafluoroethylenepropylene resin, vinyl fluoride resin, vinylidene fluoride resin, difluorodiethylene chloride resin, and their co-polymers. It is preferable that it consists of 1 type, or 2 or more types of resin chosen from coalescence.

  The fluorine-based resin particles are preferably present as primary particles dispersed in the charge transport layer 6, and therefore the average primary particle diameter of the fluorine-based resin particles is preferably 0.05 to 1.0 μm, 0 More preferably, it is 1 to 0.3 μm. In addition, when the average primary particle diameter of the fluorine-based resin particles is less than 0.05 μm, the aggregation of the fluorine-based resin particles easily proceeds, and when it exceeds 1.0 μm, image quality defects are likely to occur.

  The content of the fluorine resin particles in the charge transport layer 6 is preferably 0.1 to 40% by mass, and more preferably 1 to 30% by mass based on the total amount of the constituent materials of the protective layer 7. If the content of the fluorine-based resin particles is less than 1% by mass, the effect of modifying the charge transport layer 6 due to the use of the fluorine-based resin particles is not sufficient. On the other hand, if the content exceeds 40% by mass, the light transmittance tends to decrease. .

  Further, when the charge transport layer 6 contains fluorine-based resin particles, a dispersion for improving the dispersion stability of the fluorine-based resin particles in the charge transport layer forming coating liquid and for preventing aggregation at the time of coating film formation. It is preferable to add a fluorine-containing graft polymer as an auxiliary agent. As the fluorine-containing graft polymer, a macromonomer composed of an acrylic ester compound, a methacrylic ester compound, a styrene compound, or the like, and a resin graft-polymerized from perfluoroalkylethyl methacrylate are preferable.

  Since the fluorine-containing graft polymer functions as a dispersion aid for the fluorine-based resin particles, the amount of the fluorine-containing graft polymer is preferably selected appropriately according to the amount of the fluorine-based resin particles used. Specifically, 1.5 to 2.5% by mass is appropriate with respect to the amount of the fluorine resin particles used, and 1.6 to 2.2% by mass is particularly preferable. When the content of the fluorine-containing graft polymer is less than 1.5% by mass, the dispersibility of the fluororesin particles in the coating solution tends to be insufficient. On the other hand, when the content exceeds 2.6% by mass, it is repeatedly used. There is a tendency for the residual potential to increase due to.

  The charge transport layer 6 may further contain inorganic particles. Examples of the inorganic particles used in the present invention include alumina, silica (silicon dioxide), titanium oxide, zinc oxide, cerium oxide, zinc sulfide, magnesium oxide, copper sulfate, sodium carbonate, magnesium sulfate, potassium chloride, calcium chloride, and chloride. Examples thereof include sodium, nickel sulfate, antimony, manganese dioxide, chromium oxide, tin oxide, zirconium oxide, barium sulfate, aluminum sulfate, silicon carbide, titanium carbide, boron carbide, tungsten carbide, zirconium carbide, and the like. Species can be used alone or in combination of two or more.

  Among these, it is preferable to use silica particles. The silica particles are preferably produced by a chemical flame CVD method. As a specific example, silica particles are obtained by gas phase reaction of chlorosilane gas in a high-temperature flame of oxygen-hydrogen mixed gas or hydrocarbon-oxygen mixed gas. The method is preferred.

  In addition, as the inorganic particles, particles having a hydrophobic surface are preferable. As the hydrophobizing agent, for example, a siloxane compound, a silane coupling agent, a titanium coupling agent, a polymer fatty acid or a metal salt thereof is used. Examples of the siloxane compound include polydimethylsiloxane, dihydroxypolysiloxane, octamethylcyclotetrasiloxane, and examples of the silane coupling agent include γ- (2-aminoethyl) aminopropyltrimethoxysilane and γ- (2-aminoethyl). Aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) γ-aminopropyltrimethoxysilane hydrochloride, hexamethyldisilazane, methyltrimethoxysilane, butyltrimethoxy Silane, isobutyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, phenyltrimethoxysilane, o-methylphenyltrimeth Examples include xylsilane and p-methylphenyltrimethoxysilane.

  Moreover, 0.005-2.0 micrometers is preferable and, as for the average primary particle diameter of an inorganic particle, 0.01-1.0 micrometer is more preferable. When the average primary particle size of the inorganic fine particles is less than 0.005 μm, there is a tendency that sufficient mechanical strength cannot be imparted to the surface of the photoreceptor 1 (surface opposite to the conductive substrate 2), and aggregation during dispersion is present. Is easier to proceed. On the other hand, when the average primary particle size of the inorganic particles exceeds 2 μm, the surface roughness of the charge transport layer 6 increases, and when the electrophotographic apparatus includes a cleaning blade, the cleaning characteristics deteriorate due to wear and damage of the cleaning blade. Image blur is likely to occur.

  The content of the inorganic particles in the charge transport layer 6 is preferably 0.1 to 30% by mass, and more preferably 1 to 20% by mass based on the total amount of the constituent materials of the charge transport layer 6. When the content of the inorganic particles is less than 0.1% by mass, the modification effect due to the dispersion of the inorganic particles tends to be insufficient. On the other hand, when the content exceeds 30% by mass, the light transmittance is lowered, and further, poor dispersion tends to occur. There is a tendency.

  When fluorine resin particles and / or inorganic particles are used as the constituent material of the charge transport layer 6, when dispersing them in the charge transport layer forming coating solution, a ball mill, a vibration ball mill, an attritor, a sand mill, a horizontal type Media dispersers such as a sand mill and medialess dispersers such as agitator, ultrasonic disperser, roll mill, and high-pressure homogenizer can be used. Furthermore, as a high-pressure homogenizer, dispersion processing is performed by a collision method in which the dispersion liquid is dispersed by liquid-liquid collision or liquid-wall collision in a high-pressure state, or a penetration method in which a fine flow path is dispersed in a high-pressure state. You can also.

  In addition, additives such as an antioxidant, a light stabilizer, and a heat stabilizer are added to the photosensitive layer 3 for the purpose of preventing deterioration of the photoreceptor due to ozone, nitrogen oxide, or light or heat generated in the electrophotographic apparatus. Can be added. For example, examples of the antioxidant include hindered phenol, hindered amine, paraphenylenediamine, arylalkane, hydroquinone, spirochroman, spiroidanone and derivatives thereof, organic sulfur compounds, and organic phosphorus compounds. Examples of light stabilizers include derivatives such as benzophenone, benzoazole, dithiocarbamate, and tetramethylpipen. For the purpose of improving the smoothness of the surface, a leveling agent such as silicone oil can be added to the surface layer.

  The electrophotographic photosensitive member of the present invention is not limited to the above embodiment. For example, FIG. 1 shows a function-separated type photoreceptor in which the charge generation layer 5 and the charge transport layer 6 are separately provided. However, the photosensitive layer provided in the electrophotographic photoreceptor of the present invention includes a charge generation material and It may be a single-layer type photosensitive layer containing both the charge transport material and the same layer.

  Further, in the electrophotographic photoreceptor 1 shown in FIG. 1, the surface of the photoreceptor opposite to the conductive substrate 2 is constituted by the charge transport layer 6, but the mechanical strength of the charge transport layer 6 is insufficient. In this case, a protective layer may be further provided on the charge transport layer 6.

  Further, the electrophotographic photoreceptor of the present invention has a second intermediate layer between the intermediate layer 4 and the photosensitive layer 3 in order to improve electrical characteristics, improve image quality, improve image quality maintenance, and improve adhesion of the photosensitive layer. May be further provided.

  Examples of the binder resin used for the second intermediate layer include acetal resins such as polyvinyl butyral, polyvinyl alcohol resin, casein, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacrylic resin, acrylic resin, and polyvinyl chloride. In addition to polymer resins such as resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, melamine resin, zirconium, titanium, aluminum, manganese, There are organometallic compounds containing silicon atoms and the like. These compounds can be used alone or as a mixture or polycondensate of a plurality of compounds. Among these, organometallic compounds containing zirconium or silicon are excellent in performance, such as low residual potential, little potential change due to environment, and little potential change due to repeated use.

  Examples of organic zirconium compounds include zirconium butoxide, zirconium zirconium acetoacetate, zirconium triethanolamine, acetylacetonate zirconium butoxide, ethyl acetoacetate butoxide, zirconium acetate, zirconium oxalate, zirconium lactate, zirconium phosphonate, zirconium octoate, Zirconium naphthenate, zirconium laurate, zirconium stearate, zirconium isostearate, methacrylate zirconium butoxide, stearate zirconium butoxide, isostearate zirconium butoxide and the like.

  Examples of organosilicon compounds include vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltri Methoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl)- γ-aminopropylmethylmethoxysilane, N, N-bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, and the like. Among these, silicon compounds particularly preferably used are 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 Examples include silane coupling agents such as phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-chloropropyltrimethoxysilane.

  Examples of organic titanium compounds include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate ammonium salt , Titanium lactate, titanium lactate ethyl ester, titanium triethanolamate, polyhydroxy titanium stearate and the like.

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

  The second intermediate layer can be formed using a coating solution obtained by adding the above constituent materials to a predetermined solvent. Examples of the solvent used for forming the second intermediate layer include known organic solvents, for example, aromatic hydrocarbon solvents such as toluene and chlorobenzene, methanol, ethanol, n-propanol, iso-propanol, n-butanol and the like. Aliphatic alcohol solvents, ketone solvents such as acetone, cyclohexanone and 2-butanone, halogenated aliphatic hydrocarbon solvents such as methylene chloride, chloroform and ethylene chloride, cyclic such as tetrahydrofuran, dioxane, ethylene glycol and diethyl ether Linear ether solvents, ester solvents such as methyl acetate, ethyl acetate and n-butyl acetate, and these solvents can be used alone or in combination of two or more. When mixing, any solvent can be used as long as it can dissolve the binder resin as a mixed solvent.

  As a coating method for forming the second intermediate layer, a normal method such as a dip coating method, a push-up coating method, a wire bar coating method, a spray coating method, a blade coating method, a knife coating method, or a curtain coating method may be used. it can.

  In addition to improving the coatability of the upper layer, the second intermediate layer also serves as an electrical blocking layer. However, when the film thickness is too large, the electrical barrier becomes too strong and the potential due to desensitization or repetition is reduced. It tends to cause a rise. Therefore, when forming the second intermediate layer, the film thickness is preferably 0.1 to 3 μm.

  The electrophotographic photosensitive member of the present invention having the above-described configuration is used in electrophotographic apparatuses such as light lens type copying machines, laser beam printers that emit near-infrared light or visible light, digital copying machines, LED printers, and laser facsimiles. Can do. The electrophotographic photosensitive member of the present invention can be used in combination with a one-component or two-component developer. In addition, the photoconductor manufactured using the manufacturing method of the present invention can provide good characteristics with little current leakage even in the contact charging system using a charging roller or a charging brush.

  Next, preferred embodiments of an electrophotographic apparatus and a process cartridge equipped with the electrophotographic photosensitive member of the present invention will be described.

  FIG. 2 is a schematic configuration diagram showing a preferred embodiment of the electrophotographic apparatus of the present invention. An electrophotographic apparatus 200 shown in FIG. 2 includes an electrophotographic photosensitive member 1 of the present invention, a charging device 208 that charges the electrophotographic photosensitive member 1 by a contact charging method, a power source 209 connected to the charging device 208, and a charging device. An exposure device 210 that exposes the electrophotographic photosensitive member 207 charged by 208 to form an electrostatic latent image, and a developing device that develops the electrostatic latent image formed by the exposure device 210 with toner to form a toner image 211, a transfer device 212 that transfers a toner image formed by the developing device 211 to a transfer medium, a cleaning device 213, a static eliminator 214, and a fixing device 215. Although not shown in FIG. 2, a toner supply device that supplies toner to the developing device 211 is also provided. Moreover, in an embodiment different from the present embodiment, the static eliminator 214 may not be provided.

  The charging device 208 makes a conductive member (charging roll) contact the surface of the photoconductor 1 to uniformly apply a voltage to the photoconductor to charge the surface of the photoconductor to a predetermined potential.

  As the conductive member, a member provided with an elastic layer, a resistance layer, a protective layer and the like on the outer peripheral surface of the core material is preferably used. The shape of the conductive member may be any of a brush shape, a blade shape, a pin electrode shape, a roller shape, and the like.

  As the material of the core material, a conductive material such as iron, copper, brass, stainless steel, aluminum, nickel, or the like is used. Also, a resin molded product in which conductive particles or the like are dispersed can be used.

As the material of the elastic layer, a material having conductivity or semiconductivity, for example, a material in which conductive particles or semiconducting particles are dispersed in a rubber material can be used. As the rubber material, EPDM, polybutadiene, natural rubber, polyisobutylene, SBR, CR, NBR, silicone rubber, urethane rubber, epichlorohydrin rubber, SBS, thermoplastic elastomer, norbornene rubber, fluorosilicone rubber, ethylene oxide rubber and the like are used. Examples of the conductive particles or semiconductive particles include carbon black, zinc, aluminum, copper, iron, nickel, chromium, titanium, and other metals, ZnO—Al ₂ O ₃ , SnO ₂ —Sb ₂ O ₃ , In ₂ O ₃ — Metal oxides such as SnO ₂ , ZnO—TiO ₂ , MgO—Al ₂ O ₃ , FeO—TiO ₂ , TiO ₂ , SnO ₂ , Sb ₂ O ₃ , In ₂ O ₃ , ZnO or MgO can be used. These materials can be used individually by 1 type or in mixture of 2 or more types.

  As the material of the resistance layer and the protective layer, conductive particles or semiconductive particles are dispersed in a binder resin, and the resistance is controlled. As binder resin, acrylic resin, cellulose resin, polyamide resin, methoxymethylated nylon, ethoxymethylated nylon, polyurethane resin, polycarbonate resin, polyester resin, polyethylene resin, polyvinyl resin, polyarylate resin, polythiophene resin, PFA, FEP or A polyolefin resin such as PET or a styrene butadiene resin is used. As the conductive particles or semiconductive particles, carbon black, metal, or metal oxide similar to the elastic layer is used. Further, if necessary, an antioxidant such as hindered phenol and hindered amine, a filler such as clay and kaolin, and a lubricant such as silicone oil can be added. As a means for forming these layers, 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, a curtain coating method, or the like can be used.

  When the photosensitive member 1 is charged using these conductive members, a voltage is applied to the conductive member. The applied voltage may be a DC voltage or a DC voltage obtained by superimposing an AC voltage. In addition to the charging roll shown in this embodiment, charging by a contact charging method may be performed using a charging brush, a charging film, a charging tube, or the like. Moreover, you may charge by the non-contact system using a corotron or a scorotron.

  As the exposure device 210, an optical system device or the like that can expose a light source such as a semiconductor laser, an LED (light emitting diode), a liquid crystal shutter, or the like on the surface of the electrophotographic photosensitive member 1 in a desired image manner can be used. Among these, when an exposure apparatus capable of exposing non-interference light is used, interference fringes between the conductive substrate of the electrophotographic photosensitive member 1 and the photosensitive layer can be prevented.

  As the developing device 211, a conventionally known developing device using a regular or reversal developer such as a one-component system or a two-component system can be used.

  Examples of the transfer device 212 include a roller-type contact charging member, a contact-type transfer charger using a belt, a film, a rubber blade, or the like, a scorotron transfer charger using a corona discharge, a corotron transfer charger, or the like. .

  The cleaning device 213 is for removing residual toner adhering to the surface of the electrophotographic photosensitive member after the transfer process, and the electrophotographic photosensitive member cleaned by this is repeatedly used for the image forming process described above. . As the cleaning device, methods such as brush cleaning and roll cleaning can be used in addition to those using the illustrated cleaning blade. Among these, the cleaning blade is preferably used. Examples of the material for the cleaning blade include urethane rubber, neoprene rubber, and silicone rubber.

  In addition, the electrophotographic apparatus according to the present embodiment further includes a static eliminator such as a static eliminator (erase light irradiation device) 214 and an image fixing device 215 as shown in FIG. As a result, when the electrophotographic photosensitive member is repeatedly used, the phenomenon that the residual potential of the electrophotographic photosensitive member is brought into the next image forming cycle is prevented, so that the image quality can be further improved.

  FIG. 3 is a schematic configuration diagram showing the basic configuration of another embodiment of the electrophotographic apparatus of the present invention. The electrophotographic apparatus 220 shown in FIG. 3 is an intermediate transfer type electrophotographic apparatus. In the housing 400, four electrophotographic photoreceptors 401a to 401d (for example, the electrophotographic photoreceptor 401a is yellow and the electrophotographic photoreceptor 401b is magenta). The electrophotographic photosensitive member 401c can form an image of cyan and the electrophotographic photosensitive member 401d can form a black color) are arranged in parallel along the intermediate transfer belt 409.

  Here, the electrophotographic photoreceptors 401a to 401d mounted in the electrophotographic apparatus 220 are the electrophotographic photoreceptors of the present invention (for example, the electrophotographic photoreceptor 1), respectively.

  Each of the electrophotographic photosensitive members 401a to 401d can be rotated in a predetermined direction (counterclockwise on the paper surface), and the charging rolls 402a to 402d, the developing devices 404a to 404d, and the primary transfer roll 410a along the rotation direction. To 410d and cleaning blades 415a to 415d are arranged. Each of the developing devices 404a to 404d can be supplied with toner of four colors of black, yellow, magenta and cyan accommodated in the toner cartridges 405a to 405d, and the primary transfer rolls 410a to 410d are respectively intermediate transfer belts. 409 is in contact with the electrophotographic photoreceptors 401a to 401d.

  Further, a laser light source (exposure device) 403 is disposed at a predetermined position in the housing 400, and the surface of the electrophotographic photoreceptors 401a to 401d after charging is irradiated with laser light emitted from the laser light source 403. Is possible. Accordingly, charging, exposure, development, primary transfer, and cleaning are sequentially performed in the rotation process of the electrophotographic photosensitive members 401a to 401d, and the toner images of the respective colors are transferred onto the intermediate transfer belt 409 in an overlapping manner.

  The intermediate transfer belt 409 is supported with a predetermined tension by a drive roll 406, a backup roll 408, and a tension roll 407, and can rotate without causing deflection due to the rotation of these rolls. Further, the secondary transfer roll 413 is disposed so as to contact the backup roll 408 via the intermediate transfer belt 409. The intermediate transfer belt 409 passing between the backup roll 408 and the secondary transfer roll 413 is cleaned by, for example, a cleaning blade 416 disposed in the vicinity of the drive roll 406 and then repeatedly used for the next image forming process. Is done.

  A tray (transfer medium tray) 411 is provided at a predetermined position in the housing 400, and a transfer medium 417 such as paper in the tray 411 is transferred to the intermediate transfer belt 409 and the secondary transfer roll by a transfer roll 412. Then, the paper is sequentially transferred between the two fixing rolls 414 that are in contact with each other and the two fixing rolls 414, and then discharged to the outside of the housing 400.

  In the above description, the case where the intermediate transfer belt 409 is used as the intermediate transfer member has been described. However, the intermediate transfer member may have a belt shape like the intermediate transfer belt 409 or a drum shape. Also good. In the case of a belt shape, a conventionally known resin can be used as the resin material used as the base material of the intermediate transfer member. For example, polyimide resin, polycarbonate resin, polyvinylidene fluoride (PVDF), polyalkylene terephthalate (PAT), ethylenetetrafluoroethylene copolymer (ETFE) / PC, ETFE / PAT, blend material of PC / PAT, polyester, polyether Examples thereof include resin materials such as ether ketone and polyamide, and resin materials containing these as main raw materials. Furthermore, a resin material and an elastic material can be blended and used.

  As an elastic material, polyurethane, chlorinated polyisoprene, NBR, chloropyrene rubber, EPDM, hydrogenated polybutadiene, butyl rubber, silicone rubber, or the like can be used, or a material obtained by blending two or more kinds can be used. If necessary, a conductive agent imparting electronic conductivity or a conductive agent having ionic conductivity is added to the resin material and elastic material used for these base materials in combination of one kind or two or more kinds. Among these, it is preferable to use a polyimide resin in which a conductive agent is dispersed from the viewpoint of excellent mechanical strength. As the conductive agent, a conductive polymer such as carbon black, metal oxide, or polyaniline can be used. When a belt-shaped configuration such as the intermediate transfer belt 409 is employed as the intermediate transfer member, the thickness of the belt is generally preferably 50 to 500 μm and more preferably 60 to 150 μm, but is appropriately selected according to the hardness of the material. be able to.

  For example, a belt made of a polyimide resin in which a conductive agent is dispersed is 5 to 20% by mass as a conductive agent in a polyamic acid solution, which is a polyimide precursor, as described in JP-A-63-311263. After the carbon black is dispersed, the dispersion is cast on a metal drum and dried, and then the film peeled off from the drum is stretched at a high temperature to form a polyimide film. Can be produced.

  The film molding is generally performed by injecting a polyamic acid solution film-forming stock solution in which a conductive agent is dispersed into a cylindrical mold and, for example, heating at 100 to 200 ° C. at a rotational speed of 500 to 2000 rpm. The film was formed into a film by a centrifugal molding method while being rotated, and then the obtained film was demolded in a semi-cured state and covered with an iron core, and subjected to a polyimide reaction (polyamide acid) at a high temperature of 300 ° C. or higher. It can be carried out by proceeding a ring-closing reaction) and carrying out main curing. In addition, the stock solution is cast on a metal sheet to a uniform thickness and heated to 100 to 200 ° C. to remove most of the solvent in the same manner as described above, and then gradually raised to a high temperature of 300 ° C. or higher. There is also a method of forming a polyimide film. Further, the intermediate transfer member may have a surface layer.

  When a drum-shaped configuration is adopted as the intermediate transfer member, it is preferable to use a cylindrical substrate formed of aluminum, stainless steel (SUS), copper, or the like as the substrate. If necessary, an elastic layer can be coated on the cylindrical substrate, and a surface layer can be formed on the elastic layer.

  The transfer medium according to the present invention is not particularly limited as long as it is a medium that transfers a toner image formed on an electrophotographic photosensitive member. For example, when transferring directly from an electrophotographic photosensitive member to a transfer medium such as paper, paper or the like is the transfer medium. When an intermediate transfer member is used, the intermediate transfer member is a transfer medium.

  FIG. 4 is a sectional view schematically showing a basic configuration of a preferred embodiment of a process cartridge including the electrophotographic photosensitive member of the present invention. In addition to the electrophotographic photosensitive member 1, the process cartridge 400 is attached to a charging device 208, a developing device 211, a cleaning device (cleaning means) 213, an opening 217 for exposure, and an opening 218 for static elimination exposure. Are combined and integrated with each other.

  The process cartridge 400 is detachable from the main body of the electrophotographic apparatus including the transfer device 212, the fixing device 215, and other components (not shown). It constitutes.

  The above-described electrophotographic apparatuses 200 and 220 and the process cartridge 400 include the electrophotographic photosensitive member of the present invention, so that even when used with a contact charging device, image quality defects such as fog do not occur and high image quality is achieved. An image of (image quality) can be obtained, and the stability of the image quality can be improved.

EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example at all.
[Example 1]
In a solution obtained by dissolving 24 parts by mass of polyvinyl butyral resin (ESREC BM-1, Sekisui Chemical Co., Ltd.) in 400 parts by mass of isopropyl alcohol, 6 parts by mass of 1,3-ethylmethylimidazolium tetrafluoroborate and block type isocyanate (Sumi Joule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.) 70 parts by mass, silicone ball (Tospearl 120, manufactured by Toshiba Silicone Co., Ltd.) 10 parts by mass, and dioctyltin dilaurate 0.07 parts by mass are mixed with stirring and applied to the intermediate layer. A liquid was obtained. This coating solution was dip coated on a 30 mmφ aluminum substrate and dried and cured at 160 ° C. for 100 minutes to form an intermediate layer.

  Next, at a Bragg angle (2θ ± 0.2 °) of an X-ray diffraction spectrum using Cu—Kα ray as a charge generation material, 7.4 °, 16.6 °, 25.5 ° and 28.3 A mixture comprising 15 parts by mass of gallium chloride phthalocyanine having a diffraction peak at the position of °, 10 parts by mass of vinyl chloride-vinyl acetate copolymer resin (VMCH, manufactured by Nihon Unicar) and 300 parts by mass of n-butyl alcohol. Was dispersed in a sand mill for 4 hours to obtain a coating solution for forming a charge generation layer. The obtained dispersion was dip-coated on the intermediate layer and dried to form a charge generation layer having a thickness of 0.2 μm.

Next, 8 parts by mass of tetrafluoroethylene resin particles, 0.16 parts by mass of a fluorine-based graft polymer as a dispersion aid, 49 parts by mass of tetrohydrofuran and 21 parts by mass of toluene were sufficiently stirred and mixed. A resin particle suspension was prepared. Subsequently, 20 parts by mass of N, N′-bis (3-methylphenyl) -N, N′-diphenylbenzidine and 20 parts by mass of N, N′-bis (3,4-dimethylphenyl) biphenyl-4-amine 60 parts by mass of bisphenol Z polycarbonate resin (viscosity average molecular weight 40,000) was sufficiently dissolved and mixed in 231 parts by mass of Tetrohydrofuran and 99 parts by mass of toluene. A high-pressure homogenizer (trade name LA-33S, manufactured by Nanomizer Co., Ltd.) equipped with a penetrating chamber having fine flow paths after adding the above tetrafluoroethylene resin particle suspension to this solution and stirring and mixing. The coating liquid for forming a charge transport layer was prepared by repeating the dispersion treatment by increasing the pressure up to 500 kgf / cm ² four times. The obtained coating solution was dip-coated on the charge generation layer and dried to form a charge transport layer having a thickness of 26 μm.
[Example 2]
Except for using 6 parts by mass of 1,3-ethylmethylimidazolium hexafluorophosphate instead of 6 parts by mass of 1,3-ethylmethylimidazolium tetrafluoroborate when preparing the coating solution for forming the intermediate layer. In the same manner as in Example 1, an electrophotographic photosensitive member was produced.
[Example 3]
Except for using 6 parts by mass of 1,3-ethylmethylimidazolium trifluoromethanesulfonate instead of 6 parts by mass of 1,3-ethylmethylimidazolium tetrafluoroborate when preparing the coating solution for forming the intermediate layer. In the same manner as in Example 1, an electrophotographic photosensitive member was produced.
[Example 4]
30 parts by mass of an organic zirconium compound (acetylacetone zirconium butyrate), an organic silane compound (γ) in a solution in which 4 parts by mass of a polyvinyl butyral resin (ESREC BM-S, manufactured by Sekisui Chemical Co., Ltd.) is dissolved in 70 parts by mass of N-butyl alcohol. -Aminopropyltrimethoxysilane) 3 parts by mass and 1,3-butylmethylimidazolium tetrafluoroborate 2 parts by mass were added, mixed and stirred to obtain a coating solution for forming an intermediate layer. This coating solution was dip-coated on a 30 mmφ aluminum substrate and dried and cured at 170 ° C. for 100 minutes to form an intermediate layer.

An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the undercoat layer was formed as described above.
[Example 5]
Example 4 except that 2 parts by mass of 1-methylpyrazolium tetrafluoroborate was used instead of 2 parts by mass of 1,3-butylmethylimidazolium tetrafluoroborate when preparing the coating solution for forming the intermediate layer In the same manner as above, an electrophotographic photosensitive member was produced.
[Example 6]
In a solution prepared by dissolving 24 parts by mass of polyvinyl butyral resin (ESREC BM-1, Sekisui Chemical Co., Ltd.) in 400 parts by mass of isopropyl alcohol, 6 parts by mass of the ionic liquid (5-1) in Table 1 and block type isocyanate (Sumi Joule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.) 70 parts by mass, silicone ball (Tospearl 120, manufactured by Toshiba Silicone Co., Ltd.) 10 parts by mass, and dioctyltin dilaurate 0.07 parts by mass are mixed with stirring, and applied for an intermediate layer. A liquid was obtained. This coating solution was dip-coated on a 30 mmφ aluminum support and dried and cured at 160 ° C. for 100 minutes to form an intermediate layer.

  Next, as a charge generation material, 7.4 °, 16.6 °, 25.5 at a Bragg angle (2θ ± 0.2 °) of an X-ray diffraction spectrum using Cu—Kα rays as a charge generation material. Using gallium chloride phthalocyanine having a diffraction peak at the positions of ° and 28.3 °, 15 parts by mass thereof, 10 parts by mass of vinyl chloride-vinyl acetate copolymer resin (VMCH, manufactured by Nihon Unicar Company) and n-butyl alcohol 300 The mixture consisting of parts by mass was dispersed for 4 hours in a sand mill to obtain a coating solution for forming a charge generation layer. The obtained coating solution was dip-coated on the intermediate layer and dried to form a charge generation layer having a thickness of 0.2 μm.

Next, 8 parts by mass of tetrafluoroethylene resin particles, 0.16 parts by mass of a fluorine-based graft polymer as a dispersion aid, 49 parts by mass of tetrohydrofuran and 21 parts by mass of toluene were sufficiently stirred and mixed. A resin particle suspension was prepared. Subsequently, 20 parts by mass of N, N′-bis (3-methylphenyl) -N, N′-diphenylbenzidine and 20 parts by mass of N, N′-bis (3,4-dimethylphenyl) biphenyl-4-amine 60 parts by mass of bisphenol Z polycarbonate resin (viscosity average molecular weight 40,000) was sufficiently dissolved and mixed in 231 parts by mass of Tetrohydrofuran and 99 parts by mass of toluene. A high-pressure homogenizer (trade name LA-33S, manufactured by Nanomizer Co., Ltd.) equipped with a penetrating chamber having fine flow paths after adding the above tetrafluoroethylene resin particle suspension to this solution and stirring and mixing. The coating liquid for forming a charge transport layer was prepared by repeating the dispersion treatment by increasing the pressure up to 500 kgf / cm ² four times. The obtained coating solution was dip-coated on the charge generation layer and dried to form a charge transport layer having a thickness of 26 μm to obtain an electrophotographic photosensitive member.
[Example 7]
When preparing the coating solution for forming an intermediate layer, an electron was prepared in the same manner as in Example 6 except that the ionic liquid (5-2) was used instead of the ionic liquid (5-1) in Table 1. A photographic photoreceptor was prepared.
[Example 8]
When preparing the coating solution for forming an intermediate layer, an electron was prepared in the same manner as in Example 6 except that the ionic liquid (6-1) was used instead of the ionic liquid (5-1) in Table 1. A photographic photoreceptor was prepared.
[Example 9]
In a solution obtained by dissolving 24 parts by mass of polyvinyl butyral resin (ESREC BM-1, Sekisui Chemical Co., Ltd.) in 400 parts by mass of isopropyl alcohol, 6 parts by mass of ionic liquid (7-1) in Table 1 and block type isocyanate ( 70 parts by mass of Sumijoule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.), 10 parts by mass of silicone balls (Tospearl 120, manufactured by Toshiba Silicone Co., Ltd.) and 0.07 parts by mass of dioctyltin dilaurate are added and mixed by stirring to form an intermediate layer. A coating solution was obtained. This coating solution was dip-coated on a 30 mmφ aluminum support and dried and cured at 160 ° C. for 100 minutes to form an undercoat layer.

An electrophotographic photosensitive member was produced in the same manner as in Example 6 except that the intermediate layer was formed as described above.
[Example 10]
When preparing the coating solution for forming an intermediate layer, an electron was prepared in the same manner as in Example 9 except that the ionic liquid (7-2) was used instead of the ionic liquid (5-1) in Table 1. A photographic photoreceptor was prepared.
[Example 11]
When preparing the coating solution for forming an intermediate layer, an electron was prepared in the same manner as in Example 9 except that the ionic liquid (8-1) was used instead of the ionic liquid (5-1) in Table 1. A photographic photoreceptor was prepared.
[Example 12]
When preparing the coating solution for forming the intermediate layer, an electron was prepared in the same manner as in Example 9 except that the ionic liquid (8-2) was used instead of the ionic liquid (5-1) in Table 1. A photographic photoreceptor was prepared.
[Comparative Example 1]
30 parts by mass of an organic zirconium compound (acetylacetone zirconium butyrate) and an organic silane compound (γ) in a solution in which 4 parts by mass of a polyvinyl butyral resin (ESREC BM-S, manufactured by Sekisui Chemical Co., Ltd.) are dissolved in 170 parts by mass of n-butyl alcohol. -Aminopropyltrimethoxysilane) 3 parts by mass was added and mixed and stirred to obtain a coating solution for forming an intermediate layer. This coating solution is dip-coated on a 30 mmφ aluminum substrate roughened by a honing treatment, air-dried at room temperature for 5 minutes, and then the substrate is heated to 50 ° C. over 10 minutes, to 50 ° C. and 85 ° C. It was put in a constant temperature and humidity chamber of% RH (dew point 47 ° C.) and subjected to a humidification hardening acceleration treatment for 20 minutes. Then, it put into the hot air dryer and dried for 10 minutes at 170 degreeC, and formed the intermediate | middle layer.

An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the intermediate layer was formed as described above.
[Comparative Example 2]
2-butanone 44 parts by weight polyvinyl butyral resin (S-REC BM-1, manufactured by Sekisui Chemical Co., Ltd.) 6 parts by weight zinc oxide 35 parts by weight and block type isocyanate (Sumijour 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.) 15 parts by mass were added and mixed. The mixed solution was subjected to a dispersion treatment for 2 hours with a sand mill using 1 mmφ glass beads to obtain a dispersion. To the obtained dispersion, 0.005 parts by mass of dioctyltin dilaurate and 17 parts by mass of silicone balls (Tospearl 130, manufactured by GE Toshiba Silicone) were added as a catalyst to obtain a coating solution for forming an intermediate layer. This coating solution was dip-coated on a 30 mmφ aluminum substrate and dried and cured at 160 ° C. for 100 minutes to form an intermediate layer.

An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the intermediate layer was formed as described above.
(Production of electrophotographic apparatus and continuous print test)
The electrophotographic apparatus shown in FIG. 3 was produced using the photoreceptors of Examples 1 to 5 and Comparative Examples 1 and 2. The produced photoreceptor was equipped with a contact charging type charging device, and the same elements as those of the full color printer DocuCenter Color 400 CP manufactured by Fuji Xerox Co., Ltd. were used for the elements other than the photoreceptor.

Next, using each of the obtained electrophotographic apparatuses, in an environment of 28 ° C. and 85% RH, in an A4 size and full color mode, the image density (ratio of the printed image area on the paper) is 50000 at 5%. A sheet continuous printing test was conducted. The residual potential (Rp) after static elimination was measured for the photoconductor after the initial printing test and after printing 30000 sheets, and the difference (ΔRp) between the initial residual potential and the residual potential after printing 30,000 sheets was calculated. The results are shown in Table 2. In Table 2, the smaller ΔRp,
It means stable electrophotographic characteristics.

Table 2 also shows the initial print quality evaluation results of the 15000th and 30000th sheets obtained in this test. In Comparative Examples 1 and 2, since an image defect was observed on the 15000th sheet, the test was stopped, and the print image quality evaluation for the 30000th sheet was not performed (“interruption” in the table).

1 is a schematic cross-sectional view showing a preferred embodiment of an electrophotographic photoreceptor of the present invention. 1 is a schematic configuration diagram showing a preferred embodiment of an electrophotographic apparatus of the present invention. It is a schematic block diagram which shows other embodiment of the electrophotographic apparatus of this invention. 1 is a schematic configuration diagram showing a preferred embodiment of a process cartridge of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 401a-401d ... Electrophotographic photoreceptor, 2 ... Conductive substrate, 3 ... Photosensitive layer, 4 ... Undercoat layer, 5 ... Charge generation layer, 6 ... Charge transport layer, 200, 220 ... Electrophotographic apparatus, 208 ... Charging device 209 ... Power source 210 ... Exposure device 211 ... Developing device 212 ... Transfer device 213 ... Cleaning device 214 ... Chargeer 215 ... Fixing device 216 ... Toner supply device 217 ... Opening for exposure , 218 ... opening for static elimination exposure, 219 ... mounting rail, 300 ... process cartridge, 400 ... housing, 402a to 402d ... charging roll, 403 ... laser light source (exposure device), 404a to 404d ... developing device, 405a ˜405d ... toner cartridge, 406 ... drive roll, 407 ... tension roll, 408 ... backup roll, 409 ... medium Transfer belt, 410a to 410d ... primary transfer roll, 411 ... tray (transfer medium tray), 412 ... transfer roll, 413 ... secondary transfer roll, 414 ... fixing roll, 415a-415d ... cleaning blade, 416 ... cleaning blade 417, 500: Medium to be transferred.

Claims (7)

A conductive substrate, an intermediate layer provided on the conductive substrate, and a photosensitive layer provided on the intermediate layer;
The electrophotographic photoreceptor, wherein the intermediate layer contains an ionic liquid and a binder resin for holding the ionic liquid in the intermediate layer. 2. The electrophotographic photoreceptor according to claim 1, wherein the ionic liquid is at least one selected from compounds represented by the following general formulas (1) to (8).

[Wherein, R ¹ represents a group of carbon atoms having 2 to 10 carbon atoms constituting a ring together with N ⁺ , and R ² is a chain carbonization of 1 to 8 carbon atoms which may contain a hydrogen atom or a heteroatom. Represents a hydrogen group, X ⁻ represents an anion, p represents 1 or 2, p is 1 when the bond between N ⁺ and another atom contains one double bond, N ⁺ and other When all the bonds with the atoms are single bonds, p is 2. When p is 2, two R ^{2 s} may be the same or different. ]

[Wherein R ³ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with C, N ⁺ and N, and R ⁴ , R ⁵ and R ⁶ may be the same or different, and each represents a hydrogen atom, Alternatively, it represents a C 1-8 chain hydrocarbon group which may contain a hetero atom, and X ⁻ represents an anion. ]

[Wherein, R ⁷ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with N ⁺ , C and N, and R ⁸ and R ⁹ may be the same or different, and each represents a hydrogen atom or a heteroatom. the represents comprise also a good C1-8 chain hydrocarbon group, X ^- represents an anion. ]

[Wherein, Q represents a nitrogen atom, a phosphorus atom or a sulfur atom, and R ¹⁰ , R ¹¹ , R ¹² and R ¹³ may be the same or different and each may contain a hydrogen atom or a hetero atom. Represents a good chain hydrocarbon group having 1 to 8 carbon atoms, X- represents an anion, q represents 0 or 1, q is 0 when Q is a sulfur atom, and Q is a nitrogen atom or a phosphorus atom. When q is 1. ]

[Wherein, R ¹⁴ represents a group of carbon atoms having 2 to 10 carbon atoms constituting a ring together with N ⁺ , and R ¹⁵ is a chain carbonization of 1 to 8 carbon atoms which may contain a hydrogen atom or a heteroatom. A represents a hydrogen group, A represents a monovalent substituent having an anionic property, r represents an integer of 0 to 2, a bond between N ⁺ and another atom contains one double bond, and N ^{When +} and A ⁻ are bonded, r is 0, and when the bond between N ⁺ and another atom includes one double bond or when N ⁺ and A ⁻ are not bonded r is 1, r is 2 when the bonds of N ⁺ and other atoms are all single bonds, and N ⁺ and A ⁻ are not bonded, and two R ² when r is ^2. May be the same or different. ]

[Wherein R ¹⁶ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with C, N ⁺ and N, and R ¹⁷ and R ¹⁸ may be the same or different, and each represents a hydrogen atom or a heteroatom. Represents a chain hydrocarbon group having 1 to 8 carbon atoms which may contain A, and A represents a monovalent substituent having anionic property. ]

[Wherein R ¹⁹ represents an atomic group having 2 to 10 carbon atoms constituting a ring together with N ⁺ , C and N, and R ²⁰ is a hydrogen atom or a C ¹ to C 8 which may contain a hetero atom. Represents a chain hydrocarbon group, and A represents a monovalent substituent having an anionic property. ]

[Wherein, Q represents a nitrogen atom, a phosphorus atom or a sulfur atom, and R ²¹ , R ²² and R ²³ may be the same or different and each may contain a hydrogen atom or a hetero atom. 1 to 8 chain hydrocarbon group, A represents a monovalent substituent having an anionic property, t represents 0 or 1, t is 0 when Q is a sulfur atom, and Q is a nitrogen atom Or t is 1 when it is a phosphorus atom. ] The ionic liquid is represented by the general formula (2) or (6) and is a ring composed of R ³ , C, N ⁺ and N, or R ¹⁶ , C, N ⁺ and N The electrophotographic photoreceptor according to claim 2, wherein the constituted ring is one selected from an imidazole ring, a 2-imidazoline ring, a tetrahydropyrimidine ring, a diazabicyclo ring, and a pyridine ring. The film thickness of the said intermediate | middle layer is 15 micrometers or more, and the volume resistivity of the said intermediate | middle layer is 1 * 10 < ⁷ > -1 * 10 < ¹³ > ohm * cm, The any one of Claims 1-3 characterized by the above-mentioned. The electrophotographic photosensitive member according to claim 1. An electrophotographic photosensitive member comprising a conductive substrate, an intermediate layer provided on the conductive substrate, and a photosensitive layer provided on the intermediate layer,
Adding an ionic liquid that is liquid at room temperature, a binder resin or a precursor thereof to a predetermined solvent, and dissolving, emulsifying, or dispersing to obtain a coating solution for forming an intermediate layer;
Applying the intermediate layer forming coating solution onto a conductive substrate and drying to form an intermediate layer containing the ionic liquid and the binder resin;
And a step of applying a coating solution for forming a photosensitive layer on the intermediate layer and drying to form a photosensitive layer. The electrophotographic photosensitive member according to any one of claims 1 to 4,
A charging device for charging the electrophotographic photoreceptor;
An exposure apparatus that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image; and
A developing device for developing the electrostatic latent image to form a toner image;
An electrophotographic apparatus comprising: a transfer device that transfers the toner image from the electrophotographic photosensitive member to a transfer medium. The electrophotographic photosensitive member according to any one of claims 1 to 4,
A charging device that charges the electrophotographic photosensitive member, a developing device that develops an electrostatic latent image formed by exposure to form a toner image, and a cleaning device that removes toner remaining on the electrophotographic photosensitive member after transfer A process cartridge comprising at least one selected from

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