JPH1165152A - Electrophotographic photoreceptor, its production and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide photoreceptor having excellent wear resistance in repeated use, little residual potential and excellent fast responsiveness by incorporating a copolymer containing charge transfer blocks and insulating blocks into a charge transfer material and using an copolymer showing phase separation of a charge transfer phase and a insulating phase as the copolymer above described. SOLUTION: A charge generating layer 4 is formed on a conductive base body 1, and an intermediate layer 8 comprising a first charge transfer layer and a charge transfer matrix is formed thereon. Further, a charge transfer layer 5 containing crosslinked copolymers is formed. Moreover, a base coating layer 3 is formed between the conductive supporting body 1 and the charge generating layer 4. Relating to this photoreceptor, the charge transfer layer 5 contains at least a copolymer having a three-dimensional molecular structure by crosslinking and containing charge transfer blocks and insulating blocks, and this copolymer shows phase separation of a charge transfer phase and an insulating phase. Thereby, the obtd. photoreceptor has excellent wear resistance, little residual potential and excellent fast responsiveness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member comprising a conductive substrate having excellent wear resistance and a photosensitive layer. The present invention also relates to a method for producing these electrophotographic photoreceptors. The present invention also relates to an electrophotographic apparatus using such an electrophotographic photosensitive member.

[0002]

2. Description of the Related Art In recent years, electrophotographic technology has played a central role in the fields of copiers, printers, facsimile machines and the like because of its advantages such as high speed and high printing quality. 2. Description of the Related Art As an electrophotographic photoreceptor used in the electrophotographic technology, a photoconductor using an inorganic photoconductive material such as selenium, a selenium-tellurium alloy, or a selenium-arsenic alloy has been widely known. On the other hand, research on electrophotographic photoreceptors using organic photoconductive materials, which have advantages in terms of cost, manufacturability, disposability, etc., compared with these inorganic photoreceptors, has also become active. It has surpassed the body. In addition to a single-layer photoreceptor in which a phthalocyanine-based compound or the like is dispersed as a charge-generating material in a resin, a function-separated-type lamination structure in which photocharge generation and charge transport, which are the elementary processes of photoconduction, are carried on separate layers, respectively. With the development of such a device, the degree of freedom in material selection has been increased and the performance has been remarkably improved. At present, this function-separated laminated organic photoreceptor has become the mainstream of the electrophotographic photoreceptor. The charge generation layer for the function-separated laminated organic photoreceptor is formed by directly depositing a pigment having a charge generation ability such as a quinone pigment, a perylene pigment, an azo pigment, a phthalocyanine pigment, or selenium by vapor deposition or the like. Alternatively, those having a high concentration dispersed in a binder resin have been put to practical use. On the other hand, as the charge transporting layer, a layer in which a low-molecular compound having a charge transporting property such as a hydrazone compound, a benzidine compound, an amine compound, or a stilbene compound is molecularly dispersed in an insulating resin is used.

The durability required for electrophotographic photoreceptors is becoming severer year by year. In order to solve the problems such as abrasion and scratches on the surface layer due to repeated use, it is necessary to study techniques necessary for improving the durability. Continued. In response to these requirements, many studies have been made on surface protective layers. However, if the surface protective layer is composed of only a cross-linkable curable resin, the surface protective layer becomes an insulating layer, and the photoelectric characteristics of the photoconductor are sacrificed. Specifically, the problem that the development potential margin is narrowed due to an increase in the light portion potential at the time of exposure, and the residual potential after static elimination is increased, especially when long-term repeated printing is performed, image density is reduced. There was a problem of lowering.

As a method for improving the photoelectric characteristics, a method has been reported in which a conductive metal oxide fine powder is dispersed in a surface protective layer as a resistance control material. (Japanese Patent Laid-Open No. 57-1283
44) The decrease in the photoreceptor photoelectric characteristics due to this method is small, and the above-mentioned problems are remarkably improved. However, the resistance value of the metal oxide generally used as the conductive fine powder,
There is a problem that it largely depends on the humidity of the environment. Therefore, especially under high temperature and high humidity, the surface resistance of the photoreceptor decreases,
There is an essential problem that image quality is greatly reduced due to blurring of the electrostatic latent image.

As another method for improving the photoelectric characteristics, a method has been reported in which a charge transporting material is dispersed in a binder resin, and then the binder resin is cured to form a surface protective layer. According to this method, the surface resistance of the photosensitive member does not depend on the humidity, and there is no problem of image quality. However, the addition of a low-molecular-weight component such as a charge-transporting substance inhibits the curing reaction and lowers the mechanical strength of the surface protective layer. Therefore, even when a cross-linking curable resin having high mechanical strength is used alone, the mechanical strength of the surface protective layer is greatly reduced by adding a low-molecular component such as a charge transport material essential for improving photoelectric properties. .

[0006] On the other hand, it has been proposed to crosslink a charge transporting polymer compound to make the molecular structure three-dimensional and to cure it. In this method, although the mechanical strength is not reduced by the inhibition of the curing reaction by the low molecular weight compound, the cross-linking site exists at the site directly bonded to the charge transporting site. Cross-linked sites (or uncross-linked sites that could not react) adversely affect the charge transport site, causing problems such as an increase in residual potential and deterioration in repetition stability.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances in the prior art, and has an excellent wear resistance upon repeated use, at the same time, a small residual potential and a high speed response. An object of the present invention is to provide an electrophotographic photoreceptor excellent in image quality.

[0008]

Means for Solving the Problems The present inventors have made intensive studies on charge transporting materials and polymer materials, and as a result,
By a block or graft copolymerization technique in which a plurality of blocks having a desired function are linked by a covalent bond, a multifunctional material can be obtained without impairing each function, and a three-dimensional molecular structure can be obtained by crosslinking. The copolymer consisting of the charge transporting block and the insulating block is a charge transporting material, and has excellent overall properties as a surface layer,
The present invention has been found to be suitable, and the present invention has been completed.

That is, an object of the present invention is to provide an electrophotographic photosensitive member having at least a photosensitive layer containing a charge generating material and a charge transporting material on a conductive substrate, wherein the charge transporting material has a three-dimensional molecular structure by at least crosslinking. An electrophotographic photoreceptor comprising a copolymer containing a charge transporting block and an insulating block, wherein the copolymer is separated into a charge transporting phase and an insulating phase. To solve the problem.

[0010] In particular, the present invention relates to the following general formula (1) in a repeating unit of a charge transporting block in a copolymer comprising a charge transporting block and an insulating block, whose molecular structure is made three-dimensional by the crosslinking. Or an electrophotographic photoreceptor containing at least a repeating unit having a triarylamine structure represented by (2).
This photoreceptor has excellent charge transport performance.

Embedded image (Wherein, Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group, X ¹ is a divalent hydrocarbon group or a hetero atom-containing hydrocarbon group having an aromatic ring structure, X ² And X ³ each independently represent a substituted or unsubstituted arylene group; L ¹ represents a divalent hydrocarbon group or a heteroatom-containing hydrocarbon group which may have a branched or ring structure; , 0 or 1 respectively
Means an integer selected from )

Embedded image (In the formula, Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group, and L ² represents a trivalent hydrocarbon group having an aromatic ring structure or a heteroatom-containing hydrocarbon group.)

[0011] Further, the present invention is characterized in that the insulating block is made of a polymer of a vinyl-based monomer, so that mechanical strength, flexibility, visible and infrared light transmittance, chemical stability, insulation and the like are obtained. It is preferred in terms of. In particular, the vinyl monomer is at least one of the compounds represented by the following general formula (3).
A polymer of a vinyl monomer containing at least one kind of a compound having a crosslinkable functional group represented by the following general formula (4) is suitable.

Embedded image (Wherein, R ^{1 to} R ³ each independently represent a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group or an aryl group, and R ⁴ represents a halogen atom, or a substituted or unsubstituted alkyl group or an aryl group. , An alkoxy group, an acyl group, an acyloxy group, or an alkoxycarbonyl group.)

Embedded image (Wherein, R ^{5 to} R ⁷ each independently represent a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl or aryl group, and R ⁸ represents a chlorosulfone group, a carboxyl group, a hydroxy group, a mercapto group, a nitrile Represents an alkyl group, an aryl group, an alkoxy group, an acyl group, an acyloxy group, or an alkoxycarbonyl group substituted with a group, an isocyanate group, an amino group, an epoxy group or an alkoxysilyl group.)

[0012] Furthermore, it has a crosslinkable functional group,
By applying a solution containing a block copolymer or a graft copolymer composed of a charge transporting block and an insulating block and then crosslinking, a uniform and good crosslinked polymer film is formed. Furthermore, the charge transport material of the present invention have a hydroxy group, a copolymer composed of an insulating block and the charge-transport blocks, polyvalent isocyanate -
It is preferable to include a crosslinked polymer with the compound.

Furthermore, the charge transporting material of the present invention contains a crosslinked polymer by a condensation reaction between functional groups in a copolymer containing a charge transporting block and an insulating block, thereby adding a crosslinking agent. It is not necessary, and it is possible to eliminate the adverse effect on the charge transporting property caused by the cross-linking agent remaining in the charge transporting phase. For example, an alkoxysilyl group can be crosslinked by a condensation reaction between alkoxysilyl groups.
Since the alkoxysilyl group has an appropriate reactivity,
It is advantageous for synthesis and handling, and can easily cause a cross-linking reaction. Further, alcohol generated by condensation is also preferable because it does not remain in the photosensitive layer by being vaporized.

Such an electrophotographic photoreceptor can also be manufactured by the following manufacturing method. By using such a manufacturing method, an electrophotographic photoreceptor excellent in charge transport performance at low cost can be manufactured. it can. That is, a layer having a non-three-dimensional molecular structure, a cross-linkable functional group-containing block copolymer or graft copolymer having a charge transporting block and an insulating block as a main component of the matrix is formed. After the film is formed, the molecular structure of the block copolymer or the graft copolymer is made three-dimensional by cross-linking.

Further, the charge transporting block in the block copolymer or the graft copolymer having a charge transporting block and an insulating block, wherein the molecular structure is not three-dimensional and has a crosslinkable functional group. And the insulating block are incompatible with each other, so that the copolymer including the charge transporting block and the insulating block, the molecular structure of which has been made three-dimensional by the cross-linking, has a charge transporting phase and an insulating property. An electrophotographic photoreceptor having a phase separated from a phase can be produced.

Further, the crosslinkable functional group in the block copolymer or the graft copolymer containing a charge transporting block and an insulating block, the molecular structure of which is not three-dimensional and has a crosslinkable functional group. Since the group is mainly present only in the insulating block, it is possible to manufacture the electrophotographic photoreceptor having no charge-transporting phase without a crosslinked portion or an uncrosslinked portion, and further, to have a good charge-transporting performance. Can be manufactured.

Further, the electrophotographic photoreceptor of the present invention comprises:
Because of its excellent charge transport ability and mechanical properties, it has excellent repetition stability and reliability.
And the apparatus unit.

Further, according to the present invention, the molecular structure is 3
Inclusion of a three-dimensional copolymer containing a charge transport block and an insulating block in the surface layer improves solvent resistance, and thus causes problems such as cracks even in combination with the liquid development method. It can be used preferably without any.

In the following, a “copolymer having a charge transporting block and an insulating block whose molecular structure is made three-dimensional by crosslinking” is referred to as a “crosslinked copolymer”.
The term "copolymer having a crosslinkable functional group, including a charge transporting block and an insulating block" is referred to as a "copolymer having a crosslinkable functional group", and the term "copolymer having a crosslinkable functional group," A copolymer containing a functional block and an insulating block, which has not yet been cross-linked, is abbreviated as "a copolymer before cross-linking."

The term "insulating property" as used herein means that the transport energy level is largely different from the transport energy level of the main transport charge, and the transport charge is substantially not injected at the ordinary electric field strength, and the main transport charge is not substantially injected. It means that the electric charge is in a practically electrically insulating state. The fact that the molecular structure is not three-dimensional does not mean that the molecular structure is not 100% three-dimensional, but that the copolymer is substantially uniformly dissolved in the coating liquid and can be applied. Some of the functional groups may be cross-linked as long as the fluidity is maintained.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, each layer constituting the electrophotographic photosensitive member of the present invention will be described in more detail. The photosensitive layer may be a single layer type in which a charge generating substance is dispersed and contained in a resin, or may be a stacked type including a charge generating layer and a charge transporting layer. Further, the charge transport layer may be two or more layers. Further, an intermediate layer composed of a charge transporting matrix may be provided between the charge generation layer and the charge transport layer. Furthermore, the photoreceptor of the present invention may include a surface protective layer. The crosslinked copolymer may be contained in any layer, but is preferably contained in the outermost layer. An example of an electrophotographic photoreceptor using the crosslinked copolymer of the present invention will be described with reference to the drawings. In the drawings, each layer constituting the photoreceptor is indicated by oblique hatching, and the layer containing the crosslinked copolymer of the present invention is indicated by dots in addition to the hatching. 1 and 2 are schematic views showing a cross section of the electrophotographic photosensitive member of the present invention. FIG. 1 shows an example of a single-layer type in which a photosensitive layer 3 containing a crosslinked copolymer 1 is provided on a conductive support 2. FIG. 2 shows the photoreceptor of FIG. 1 in which an undercoat layer 4 is further provided between the conductive support 2 and the photosensitive layer 3.

FIGS. 3 and 4 are schematic views showing cross sections of an electrophotographic photosensitive member according to another embodiment of the present invention. FIG. 3 shows an example of a stacked type in which a charge generation layer 5 is provided on a conductive support 2 and a charge transport layer 6 containing a crosslinked copolymer 1 is provided. FIG. 4 is a cross-sectional view of the photoconductor shown in FIG.
Is provided.

FIGS. 5 and 6 are schematic views showing a cross section of an electrophotographic photoreceptor of another embodiment of the present invention having two charge transport layers. In FIG. 5, the charge generation layer 5 is provided on the conductive support 2, and the second charge transport layer 8 including the copolymer 1 cross-linked with the first charge transport layer 7 is provided. FIG. 6 shows the photoreceptor of FIG. 7 in which an undercoat layer 4 is further provided between the conductive support 2 and the charge generation layer 5.

FIGS. 7 and 8 are schematic views showing a cross section of an electrophotographic photosensitive member according to another embodiment of the present invention provided with an intermediate layer. In FIG. 7, the charge generation layer 5 is provided on the conductive support 2.
Is provided, an intermediate layer 9 made of a first charge transport layer 6 and a charge transporting matrix is provided, and a charge transport layer 6 containing the crosslinked copolymer 1 is further provided. FIG.
In the photoconductor of FIG. 7, an undercoat layer 4 is further provided between the conductive support 2 and the charge generation layer 5.

FIGS. 9, 10 and 11 are schematic views showing a cross section of an electrophotographic photosensitive member according to another embodiment of the present invention provided with a protective layer. In FIG. 9, on the conductive support 2,
A photosensitive layer 3 is provided, on which a surface protective layer 9 containing the crosslinked copolymer 1 is provided. In FIG. 10, the charge generation layer 5 and the charge transport layer 6 are formed on the conductive support 2.
Is provided thereon, and a surface protective layer 9 containing the crosslinked copolymer 1 is provided thereon. In FIG. 11, a charge transport layer 6 and a charge generation layer 5 are provided on a conductive support 2, and a surface protective layer 9 containing the crosslinked copolymer 1 is provided thereon.
Is provided. FIGS. 12, 13 and 14 show the photoreceptors of FIGS. 9, 10 and 11, in which an undercoat layer 4 is further provided between the conductive support 2 and the charge generation layer 5.

These electrophotographic photoreceptors can further include an irregular reflection layer, if desired. The layer containing the cross-linked copolymer is formed from a coating solution in which a molecular structure is not three-dimensionally converted and a cross-linking agent and / or a catalyst are mixed if necessary. It is obtained by performing a treatment for crosslinking accordingly.

Examples of the crosslinkable functional group include crosslinkable functional groups described in literature such as Crosslinking Agent Handbook (Taiseisha, 1981) and synthesis and application of reactive polymers (CMC, 1989). Any group can be used as long as it is a hydroxy group, an alkoxysilyl group, an epoxy group, a carboxyl group, a halogen group, an isocyanate group, a mercapto group, a chlorosulfone group, an amino group, an amide group, a tertiary amino group, Examples thereof include a nitrile group, a pyridine group, a compound having an acid anhydride structure, and a compound having a double bond. These crosslinkable functional groups may be present in either or both of the charge transport block and the insulating block, but those present only in the insulating block are formed from the charge transport block. This has little effect on the charge transporting phase, and is advantageous in electrical characteristics.

In the crosslinking reaction, a crosslinking agent and / or a catalyst and / or crosslinking conditions are provided according to the reaction. Crosslinking reactions, crosslinking agents, catalysts, and crosslinking conditions, and combinations thereof, are described in the Crosslinking Agent Handbook (Taisei,
1982), synthesis and application of reactive polymers (CMC, 1989), etc., as long as the crosslinkable functional groups are crosslinked. Examples of the crosslinking agent include a sulfur compound, an organic peroxide, a polyvalent phenol resin, a polyvalent amino resin, a polyvalent halogen compound, a polyvalent amine compound, a polyvalent azo compound, and a polyvalent isocyanate compound. And polyvalent silyl isocyanate compounds, polyvalent epoxy compounds, silane compounds, titanate compounds, polyvalent carboxylic acid compounds, acid anhydrides and the like. These crosslinkers are pre-mixed with a copolymer having a crosslinkable functional group, and then coated and cross-linked, or the copolymer is pre-coated and sprayed, immersed, or exposed to steam. Contact and crosslink.

The crosslinkable functional group is a hydroxy group,
It is particularly preferable to use a polyvalent isocyanate compound as the crosslinking agent. When the crosslinkable functional group is a hydroxy group and a polyvalent isocyanate compound is used as a crosslinking agent, a metal acetate, metal chloride, copper sulfate, di-n-butyltin dilaurate, etc. may be used as a catalyst. Can be added. Heating can be performed to promote crosslinking. As the polyvalent isocyanate compound, it is more preferable to use a derivative obtained from an isocyanate monomer or a modified polyisocyanate such as a prepolymer. Examples thereof include modified adducts obtained by adding an isocyanate to a polyol having 3 or more functional groups, modified burette obtained by modifying a compound having a urea bond with an isocyanate compound, modified allophanates obtained by adding an isocyanate to a urethane group, isocyanate Nurate modified form,
And the like, and a carbodiimide-modified product is also used. In particular, modified burettes of hexamethylene diisocyanate and modified isocyanurates of hexamethylene diisocyanate represented by structural formulas (1) and (2) are characterized by mechanical strength and electrical properties. It shows particularly excellent properties.

[0030]

Embedded image

[0031]

Embedded image

Further, as another isocyanate compound,
For example, tolylene diisocyanate (TDI), diphenylmethane diisosocyanate (MDI), 1,5-naphthylene diisocyanate, tolidine diisocyanate,
1,6-hexamethylene diisocyanate, xylene diisocyanate, lysine isocyanate, tetramethyl xylene diisocyanate, 1,3,6-hexamethylene triisocyanate, lysine ester triisocyanate, 1,6,11-undecane triisocyanate,
1,8-diisocyanate-4-isocyanatomethyloctane, triphenylmethane triisocyanate, tris (isocyanatophenyl) thiophosphate,
And general isocyanate monomers. Although included in the modified polyisocyanate, a blocked isocyanate reacted with a blocking agent for temporarily masking the activity of the isocyanate group can also be preferably used. This is preferable from the viewpoint of extending the pot life of the coating liquid.

Examples of silane compounds and titanate compounds that can be used as a crosslinking agent include the following. Specific examples thereof include vinyltrimethoxysilane, vinyltriethoxysilane, and tris-
(Β-methoxyethoxy) vinylsilane, vinyltriacetoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-mercapto Known compounds such as propyltrimethoxysilane, β-mercaptoethyltrimethoxysilane, γ-chloropropyltrimethoxysilane, isopropyltristearoyl titanate, and isopropyl methacrylisostearoyl titanate are exemplified.

When the cross-linked copolymer is a cross-linked polymer obtained by a condensation reaction between functional groups in a copolymer containing a charge transport block and an insulating block, it is necessary to add a cross-linking agent. In addition, it is possible to eliminate the adverse effect on the charge transport property caused by the cross-linking agent remaining in the charge transport phase. In particular, when the cross-linking site mainly exists only in the insulating block, or in the case of a copolymer in which the cross-linkable functional group is mainly present only in the insulating block, the cross-linking agent remains in the charge transporting phase. No cross-linking sites in the charge-transporting phase,
In addition, since there is no uncrosslinked portion, the charge transporting property is not impaired, which is particularly preferable. Examples of the functional groups capable of undergoing a condensation reaction between the functional groups include alkoxysilyl groups, isocyanate groups, a hydroxyl group and an isocyanate group. In particular, since the alkoxysilyl group has an appropriate reactivity, it is advantageous for synthesis and handling, and can easily cause a crosslinking reaction,
Further, alcohol generated by condensation is also preferable because it does not remain in the photosensitive layer due to vaporization. When the crosslinkable functional group is an alkoxysilyl group, an acid such as acetic acid or hydrochloric acid, an alkali, an organometallic compound, or the like can be added as a catalyst, and water may be further added. Heating can be performed to promote crosslinking.

The copolymer before cross-linking used in the present invention may be in any connection form of the constituent blocks.
For example, the charge transporting block is A, and the insulating block is B
AB type, ABA type, BAB type, (AB) n type,
(AB) nA-type and B (AB) n-type block copolymers, graft copolymers having a charge-transporting block as a main chain and an insulating block as a side chain, an insulating block as a main chain, charge-transporting property A and / or A are added to a side chain of a graft copolymer having a block as a side chain or a block copolymer such as an ABA type.
Or a block copolymer grafted with B-a block copolymer such as a graft copolymer, a graft copolymer, a block-
Examples include a graft copolymer.

The crosslinkable functional group of the copolymer before crosslinking used in the present invention may be contained in both or both of the charge transporting block and the insulating block. The insulating block may be formed of a block in which a repeating unit having a crosslinkable functional group is polymerized and a block in which a repeating unit having no crosslinkable functional group is polymerized. Further, the insulating block may be formed only of a block obtained by polymerizing a repeating unit having a crosslinkable functional group. In particular, the crosslinkable functional group is present only in the insulating block, and the composition ratio of the repeating unit having a crosslinkable functional group and the repeating unit having no crosslinkable functional group in the insulating block is 1:20 to A range of 10: 1 (weight ratio) is preferable, and a range of 1: 5 to 3: 1 (weight ratio) is more preferable. When the composition ratio of the repeating unit having a crosslinkable functional group exceeds the upper limit, there is a tendency to be brittle, and when the composition ratio of the repeating unit having a crosslinkable functional group falls below the lower limit, mechanical strength is increased. It tends to worsen.

The copolymer before cross-linking blocks a repeating unit having a cross-linkable functional group when forming the charge transporting block or the insulating block of the copolymer containing the charge transporting block and the insulating block. During random copolymerization,
Alternatively, it can be obtained by block copolymerization. In addition, it can be obtained by polymerizing a repeating unit having a crosslinkable functional group at the terminal of a block copolymer or a graft copolymer having no charge-crosslinkable functional group and a charge transporting block and an insulating block. Can be.

As is well known in the field of polymer blends and polymer alloys, different polymers are generally incompatible with each other, and mixtures thereof and block copolymers or graft copolymers are in a state of phase separation. take. Generally, in a mere mixture, that is, a polymer blend, the phase separation scale is macroscopic to several μm or more (macrophase separation). On the other hand, the block copolymer and the graft copolymer in which each component is connected by a covalent bond give a phase separation state composed of fine domains of submicron or less (microphase separation). It is known that the scale of phase separation in block copolymers and graft copolymers is generally the same dimension as the average length of each block, and is approximately proportional to the molecular weight. The copolymer containing a charge transporting block and an insulating block used in the present invention generally takes a microphase-separated state. However, copolymers containing a charge-transporting block and an insulating block not only necessarily take a microphase-separated state, but also some exhibit a compatibility and do not cause phase separation depending on the combination of each block. You.

In general, the phase separation state in the phase-separable block or the graft copolymer depends on the type of the constituent block,
The most thermodynamically stable structure exists due to the molecular weight, the composition ratio of both blocks, etc. In the copolymer consisting of A block and B block, it depends only on the A / B composition ratio, regardless of the connection type As the A / B ratio increases, A is a spherical domain and B is a matrix, A is a rod-shaped domain and B is a matrix, A / B alternating layers, B is a rod-shaped domain and A is a matrix, and B is a spherical domain and A is a Changes systematically into a matrix. However, when a film is formed by a wet coating method, the phase separation state can be arbitrarily controlled depending on the solvent used, the drying speed, and the like. For example, even when the A / B ratio is large and a B sphere-A matrix is taken thermodynamically, if a solvent that is both a good solvent for B and a poor solvent for A is selected as a coating solvent, A sphere-B A matrix structure can be obtained. Also, using good solvents of both A and B,
When the solvent is rapidly removed, a phase separation structure (modulation structure) frozen in a spinodal decomposition state may be obtained. In addition, when a polymer having a high A / B ratio and having a thermodynamically B-sphere-A matrix and a polymer compatible only with B is added, the amount of B-sphere increases as the amount of addition increases. Bloated,
Eventually, A gives a phase-separated structure in which a polymer compatible with only spheres and B and B serves as a matrix.

Examples of the method of synthesizing the copolymer having a crosslinkable functional group used in the present invention include the fourth edition of Experimental Chemistry Lecture 28, Polymer Synthesis (Maruzen, 1992), Macromonomer Chemistry and Industry (IPC). , 1990), polymer compatibilization and evaluation technology (Technical Information Association, 1992), block copolymers or graft copolymers described in documents such as New Polymer One Point 12 polymer alloy (Kyoritsu, 1988). Any suitable synthetic method that can provide coalescence can be used.

For example, a desired block copolymer can be obtained by previously synthesizing a charge-transporting polymer and an insulating polymer and reacting and bonding the polymers. Further, when the polymerization form of the monomer forming the charge transporting block and the monomer forming the insulating block are the same and the reactivities of both are significantly different, simply polymerizing a mixture of those monomers firstly, After the monomer having higher reactivity is polymerized and the monomer is consumed, the monomer having lower reactivity is polymerized to obtain a desired block copolymer. In addition, a polymer of one monomer is synthesized in advance, and azo, peracid ester, peroxy, dithiocarbamate,
A desired block copolymer or graft copolymer can also be obtained by introducing a polymerization initiator containing a group having a polymerization initiation ability, such as an alkali metal alcoholate or an alkali metal alkyl, and polymerizing the other monomer with the polymerization initiator. A polymer is obtained. According to this method, a block copolymer or a graft copolymer comprising a polycondensation or polyaddition polymer and an addition polymerization or ring-opening polymerization polymer can be easily obtained. In addition, azo, peracid ester,
By using a compound containing a plurality of groups having a polymerization initiation ability such as peroxy, first, one monomer is polymerized from a part of the polymerization initiation groups, and then the other monomer is polymerized from the remaining polymerization initiation groups. The desired block copolymer is also obtained. Also, a desired block copolymer can be obtained by sequentially polymerizing each monomer by a living polymerization method such as a cation living polymerization method, an anion living polymerization method, or a radical living polymerization method. The living polymerization method has an advantage that the molecular weight of each block can be easily controlled and a polymer having a narrow molecular weight distribution can be obtained. In addition, immortal polymerization method, Inifer
The desired block copolymer can also be obtained by sequentially polymerizing each monomer by a ter method or the like. Furthermore, a desired macro-copolymer can be obtained by synthesizing a macromonomer in which the other monomer has been introduced into the terminal of the polymer of one monomer in advance, and polymerizing the macromonomer.

The molecular weight of the charge transporting block and the insulating block of the copolymer of the present invention may be any value.
In order to exhibit high polymer properties, the molecular weight is desirably 2000 or more. In order to facilitate phase separation, the molecular weights of the charge transporting block and the insulating block are 2,000 or more, preferably 5,000 or more, more preferably 1,000 or more.
It is 0 or more, more preferably 20,000 or more. There is no particular limitation on the upper limit of the molecular weight in terms of electrical characteristics and mechanical characteristics.However, when a film is formed by a wet coating method, it is necessary that the upper limit of the molecular weight be within a range that gives an appropriate solution viscosity. Is preferably 5,000,000 or less.

The weight ratio between the charge transporting block and the insulating block in the copolymer of the present invention is set between 1: 9 and 9: 1. In particular, 2: 8 to 8: 2 is preferable, and 3: 7 to 7: 3 is particularly preferable. When the weight ratio of the charge transporting block is smaller than the above range, the charge transporting property cannot be sufficiently exerted, causing problems such as a decrease in photosensitivity, an increase in residual potential, and a decrease in repetition stability. Also,
When the weight ratio of the charge transporting block is larger than the above range, the mechanical strength tends to decrease. However, when it is used as a surface protective layer that requires mechanical strength rather than charge transportability, it is preferable that there be many insulating blocks.

The charge-transporting block of the cross-linked copolymer and the copolymer before cross-linking may be, for example, polyvinylcarbazole, polysilane, etc. as long as the repeating unit contains a structure having a charge-transporting property. , Any of those having a triarylamine structure in the repeating unit may have charge mobility, charge injection property, charge life,
It is preferable in terms of visible light and infrared light transmittance, chemical stability and the like.

In particular, as the triarylamine structure, at least one of the structures represented by the following general formula (1) or (2)
Those containing a seed as a repeating unit are preferred.

Embedded image

In the above general formula (1), Ar ¹ and Ar ²
Are each independently selected from a substituted or unsubstituted aryl group, and specific examples of the aryl group include a phenyl group,
Examples include a biphenyl group, a naphthyl group, and a pyrenyl group. Examples of the substituent include a methyl group, an ethyl group, a methoxy group, and a halogen atom. X ¹ is selected from a divalent hydrocarbon group having an aromatic ring structure or a hetero atom-containing hydrocarbon group. Specific examples include a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group, a methylenediphenyl group, a cyclohexyredenediphenyl group, an oxydiphenyl group, a thiodiphenyl group, and the like, and methyl-, ethyl-, and methoxy-substituted products thereof. Or a halogen-substituted compound. Among them, a substituted or unsubstituted biphenylene group is particularly preferred in view of charge transportability. X ² and X ³ are each independently selected from a substituted or unsubstituted arylene group, specifically, a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group and the like, and methyl-substituted products thereof.
Examples thereof include an ethyl-substituted product, a methoxy-substituted product, and a halogen-substituted product. L ¹ is selected from a divalent hydrocarbon group or a heteroatom-containing hydrocarbon group which may have a branched or ring structure, and is optional as long as it exhibits at least one of the above-mentioned preferable properties. Those containing a bonding group selected from an ester bond, a carbonate bond, a siloxane bond and the like, and having 20 or less carbon atoms are preferred. Specific examples include the following.

[0047]

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[0048]

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In the above general formula (2), Ar ³ and Ar ⁴
Are each independently selected from a substituted or unsubstituted aryl group, and specific examples of the aryl group include a phenyl group,
Examples include a biphenyl group, a naphthyl group, and a pyrenyl group. Examples of the substituent include an alkyl group or an alkoxy group having 1 to 12 carbon atoms, a diphenylamino group, and a halogen atom. L ² represents 3 having an aromatic ring structure
It is selected from a monovalent hydrocarbon group or a heteroatom-containing hydrocarbon group and may be any one as long as it exhibits at least one of the above-mentioned preferable characteristics, but preferably has 20 or less carbon atoms. Specific examples include the following.

[0050]

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[0051]

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The insulating block in the copolymer of the present invention may be any one of polycarbonate, polyarylate, polyester, polysulfone, polymethyl methacrylate, polyurethane and the like.
It is preferable to be made of a polymer of a vinyl monomer in terms of flexibility, transparency of visible light and infrared light, chemical stability, insulating properties and the like.

In particular, as the vinyl monomer, a monomer obtained by polymerizing at least one vinyl monomer represented by the following general formula (3) is preferable. Further, a vinyl monomer having a crosslinkable functional group represented by the general formula (4) and a vinyl monomer represented by the general formula (3) obtained by copolymerizing at least one of the vinyl monomers are preferable.

[0054]

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In the above formula (3), R ^{1 to} R ³ are each independently selected from a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl or aryl group. Specific examples of the substituted or unsubstituted alkyl group or aryl group include a methyl group, an ethyl group, a methoxy group, a chloromethyl group, a phenyl group, a tolyl group and the like. R4
Is selected from a substituted or unsubstituted alkyl group, aryl group, alkoxy group, acyl group, acyloxy group, and alkoxycarbonyl group. The alkyl group, the alkoxy group, the acyl group, the acyloxy group, and the alkoxycarbonyl group preferably have 1 to 18 carbon atoms. Examples of the aryl group include a phenyl group, a naphthyl group, and pyrenyl. Examples of the substituent include a halogen atom, a phenyl group, a hydroxy group, an amino group, an isocyanate group, an epoxy group, and an alkoxysilyl group.

[0056]

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In the above formula (4), R ^{5 to} R ⁷ are each independently selected from a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl or aryl group. Specific examples of the substituted or unsubstituted alkyl group or aryl group include a methyl group, an ethyl group, a methoxy group, a chloromethyl group, a phenyl group, a tolyl group and the like. R ⁸
Is a chlorosulfone group, a carboxyl group, a hydroxy group,
Mercapto group, nitrile group, isocyanate group, amino group, alkyl group substituted with epoxy group or alkoxysilyl group, aryl group, alkoxy group, acyl group,
It represents an acyloxy group or an alkoxycarbonyl group. The alkyl group may have a branched or cyclic structure, but preferably has 1 to 20 carbon atoms. Examples of the aryl group include a phenyl group, a naphthyl group and pyrenyl.

In the copolymer having a crosslinkable functional group of the present invention, specific examples of the structural formula represented by the above general formula (1), which is contained as a repeating unit in the charge transporting block, are shown in Tables 1 to 3 below. 4, specific examples of the structural formula represented by the above general formula (2) are shown in the following Table 5, and the above general formula (3) containing as a repeating unit in the insulating block.
Are shown in Tables 6 and 7 below, and specific examples of the crosslinking site are shown in Tables 8 to 10 below, but the present invention is not limited to these. In addition, specific examples of the charge transporting copolymer of the present invention include a block having a repeating unit of any one selected from the structures shown in Tables 1 to 3 below and a structure shown in Tables 4 and 5 below. Examples of the block copolymer include a block copolymer comprising a block having any of the above as a repeating unit, but the present invention is not limited thereto.

[0059]

[Table 1]

[0060]

[Table 2]

[0061]

[Table 3]

[0062]

[Table 4]

[0063]

[Table 5]

[0064]

[Table 6]

[0065]

[Table 7]

[0066]

[Table 8]

[0067]

[Table 9]

[0068]

[Table 10]

[0069] As the resistance value of the insulating block or insulating phase in the copolymer of the present invention is preferably at least 10 ¹³ 3Ωcm, particularly preferably 10 ¹⁴ 4Ωcm. When the resistance value of the insulating block becomes lower than the above value, transport charges enter the insulating block, causing troubles such as a decrease in charge transportability, a decrease in photosensitivity, an increase in residual potential, and a decrease in repetition stability. . It is difficult to directly measure the electric resistivity in the copolymer, and the electric resistivity of a polymer having the same structure as the insulating block or the insulating phase can be used instead.

The charge mobility of the charge-transporting block or the charge-transporting phase in the copolymer of the present invention is one factor that governs the response speed of the electrophotographic photosensitive member. It is suitably used for the electrophotographic apparatus. In the electrophotographic apparatus of the present invention, it is preferably at least 10 ⁻⁷ cm ² / Vs in an electric field intensity range used for development. More preferably, it is at least 10 ^-6 cm ² / Vs. It is difficult to directly measure the charge mobility of the charge transport block or the charge transport phase, and the charge mobility of the charge transport polymer having the same structure as the charge transport block or the charge transport phase is difficult. Can be substituted. Mobility measurement is a common practice in the industry, Time-o
It can be performed by the f-Flight method and has an electric field strength of 5
V / μm.

The phase separation structure of the charge transporting phase and the insulating phase of the crosslinked copolymer of the present invention may be any phase structure such as a sea-island structure, a cylinder-shaped structure, a lamellar structure, or a modulated structure. good. Direct observation of the phase separation state in the copolymer
There is a method of observing the stained section with a transmission electron microscope. However, as described above, the electric resistance of the phase in the copolymer,
In addition, since it is difficult to measure the charge mobility, it is difficult to directly determine whether or not the charge transporting phase and the insulating phase are separated. However, due to the nature of the polymer, if a phase-separated structure is confirmed in a copolymer of blocks composed of two or more types, each phase can be regarded as composed of the same type of blocks. for that reason,
If it is a copolymer consisting of a charge transport block and an insulating block, and if phase separation can be confirmed by any method, it is separated into a phase composed of a charge transport block and a phase composed of an insulating block. Can be considered As a matter of course, the phase composed of the charge transporting block is a charge transporting phase, and the phase composed of the insulating block is an insulating phase. As a method of confirming phase separation,
In addition to microscopy, for example, light scattering, small-angle X-ray scattering,
Thermal analysis, etc.

According to the present invention, as a charge transporting material in a photosensitive layer, a charge transporting block which is phase-separated into a charge transporting phase and an insulating phase and has a three-dimensional molecular structure by crosslinking. And a charge transporting polymer containing an insulating block, it is possible to improve abrasion resistance without impairing the charge transporting performance. That is, the matrix material forming the photosensitive layer has a charge transporting property by copolymerization, and has a structure in which a charge transporting phase and an insulating phase are separated by introducing a charge transporting block and an insulating block. Thus, the mechanical strength can be increased by making the molecular structure three-dimensional by crosslinking without impairing the charge transporting ability. In particular, by introducing a method of alloying the charge transport block and the insulating block, the degree of freedom in molecular design is greatly expanded, without impairing the charge transport ability, mechanical strength, glass transition temperature, crystallinity, Refractive index,
It is possible to control adhesiveness, adsorptivity, flexibility, solubility, meltability, phase separation state, and the like.

In particular, when the cross-linking site is mainly present only in the insulating block and the phase is separated into the charge transporting phase and the insulating phase, the cross-linking site and the uncross-linked remaining When the site is spatially separated from the charge transporting site, it is possible to minimize the adverse effect on the charge transporting performance. For this reason, an electrophotographic photoreceptor having excellent photosensitivity, residual potential, charge transport speed, repetition stability, and excellent abrasion resistance without deteriorating the charge transportability can be provided. Furthermore, the degree of freedom in designing the charge transporting site and the cross-linking site is increased, and compatibility between electrophotographic characteristics and abrasion resistance can be facilitated.

The photo-induced potential decay curve of a normal photoreceptor
Is J-shaped as shown in FIG.
The photoinduced potential decay curve depends on the photoreceptor configuration as shown in FIG.
An S-shaped electrophotographic photosensitive member can be obtained. Light induced
The S-shaped scale of the potential decay curve includes, for example,
Exposure E required to attenuate 50%_50%And 10% attenuation
Exposure E required to make_Ten%Ratio E with_50%/ E_Ten%To
Can be used. Potential decay with ideal J-shaped photoreceptor
Is proportional to the exposure,_50%/ E_Ten%The value is 5 and
Become. With a general J-shaped photoreceptor,
The charge generation efficiency and / or charge transport ability is reduced,
E_50%/ E_Ten%Indicates a value exceeding 5. On the other hand, S-shaped
The potential does not decay at all until a certain amount of exposure, which is the ultimate
Stair-like shape in which the potential attenuates to the residual potential level at once with the exposure
In the photoinduced potential decay curve of_{50 %}/ E_Ten%The value is 1
You. Therefore, the S-shape is E_50%/ E_Ten%Value is 1-5
Is defined as being within the range. Preferred digital
E _50%/ E_Ten%Value less than 3
It is preferred that More preferably a value less than 2
You.

An antioxidant, a light stabilizer, a heat stabilizer and the like are contained in the copolymer for the purpose of preventing the deterioration of the photoreceptor due to ozone or oxidizing gas generated in the electrophotographic apparatus, or light or heat. Can be added. As the antioxidant, known ones can be used, and examples thereof include hindered phenol, hindered amine, paraphenylenediamine, hydroquinone, spirochroman, spiroidanone and derivatives thereof, organic sulfur compounds, organic phosphorus compounds and the like. . As the light stabilizer, known ones can be used, for example, derivatives such as benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine, and electron withdrawing properties that can deactivate the photoexcited state by energy transfer or charge transfer. And a compound or an electron donating compound. Furthermore, various particles can be dispersed and contained in the layer containing the crosslinked copolymer in the photoreceptor of the present invention. For example, insulating particles such as a fluororesin and an inorganic filler may be dispersed for the purpose of reducing surface wear, improving transferability, improving cleanability, and the like.

The conductive support may be opaque or substantially transparent, and may include metals such as aluminum, nickel, chromium, stainless steel, and aluminum,
Titanium, nickel, chromium, stainless steel, gold, vanadium, tin oxide, indium oxide, plastic film provided with a thin film such as ITO, glass, etc., or paper, plastic film and glass coated or impregnated with a conductivity imparting agent. can give. These conductive supports are
It is used as an appropriate shape such as a drum shape, a sheet shape, and a plate shape, but is not limited thereto. Further, if necessary, various treatments can be performed on the surface of the conductive support within a range that does not affect the image quality. For example, surface oxidation treatment, chemical treatment, and coloring treatment,
Alternatively, irregular reflection processing such as graining can be performed.

One or more subbing layers may be provided between the conductive support and the photosensitive layer. The undercoat layer acts as an adhesive layer that prevents the injection of charges from the conductive support into the photosensitive layer when the photosensitive layer is charged, and that integrally holds the photosensitive layer on the conductive support. Or, in some cases, an effect of preventing reflection of light from the conductive support.

As the undercoat layer, known ones can be used. For example, polyethylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, polycarbonate resin, polyurethane resin, Polyimide resin, vinylidene chloride resin, polyvinyl acetal resin, vinyl chloride
Vinyl acetate copolymer, polyvinyl alcohol resin, water-soluble polyester resin, alcohol-soluble nylon resin,
Polymer compounds such as nitrocellulose, casein, gelatin, polyglutamic acid, starch, starch acetate, amino starch, polyacrylic acid, and polyacrylamide; or curable metal organic compounds such as zirconium alkoxide compounds, titanium alkoxide compounds, and silane coupling agents The compounds can be used alone or in combination of two or more. Further, a material capable of transporting only charges having the same polarity as the charged polarity can be used.

The thickness of the undercoat layer is 0.01 to 10
μm is appropriate, and preferably in the range of 0.05 to 5 μm. As a coating method, a blade coating method,
Wire bar coating method, spray coating method,
Conventional methods such as a dip coating method, a bead coating method, an air knife coating method, and a curtain coating method can be used.

When the photosensitive layer of the electrophotographic photosensitive member of the present invention is of a single-layer type, it can be prepared by coating a binder resin in which a charge generating material is dispersed. In a single-layer photoreceptor, when the surface protective layer is not provided, the copolymer before cross-linking of the present invention is used as a main binder resin, and a material in which a charge generation material is dispersed in the binder resin is applied. Can be produced. The photosensitive layer may contain a charge transporting low molecular weight compound and / or a charge transporting high molecular weight compound. Furthermore, a material having electron affinity can be included for the purpose of improving photosensitivity, reducing residual potential, and the like. Furthermore, to maintain chemical stability, antioxidants, and / or
UV absorbers can be included.

The mixing ratio (weight ratio) of the charge generation material and the binder resin in the photosensitive layer in the single-layer type photosensitive member of the present invention is 1:
The range of 1-1: 100 is preferred. More preferably,
It is set in the range of 1: 3 to 1:50. When the compounding ratio of the charge generation material to the binder resin is larger than the above range, dark decay is increased and mechanical properties are deteriorated. If the amount is less than the above range, problems such as a decrease in photosensitivity and an increase in residual potential occur. In addition, the thickness of the photosensitive layer in the single-layer type is generally
1 to 100 μm is suitable, preferably 5 to 50 μm
Is set in the range. As a coating method, a usual method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, or the like can be used.

The charge generation layer of the electrophotographic photoreceptor of the present invention can be prepared by coating a charge generation material by a vacuum deposition method or by dispersing or dissolving the charge generation material in a binder resin. Further, the charge generation layer may contain a charge transporting low molecular weight compound and / or a charge transporting high molecular weight compound. Furthermore, in order to maintain chemical stability, an antioxidant and / or an ultraviolet absorber may be included.

The compounding ratio (weight ratio) of the charge generating material and the binder resin in the charge generating layer of the laminated photoreceptor of the present invention is 1
The range of 0: 1 to 1:10 is preferred. More preferably,
It is set in the range of 3: 1 to 1: 1. When the compounding ratio of the charge generation material to the binder resin is larger than the above range, dark decay is increased and mechanical properties are deteriorated. If the amount is less than the above range, problems such as a decrease in photosensitivity and an increase in residual potential occur. The thickness of the charge generation layer used in the present invention is generally 0.05 to 5 μm, preferably 0.1 to 5 μm.
It is set in the range of ２．０2.0 μm. As the application method,
Conventional methods such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, and a curtain coating method can be used.

As the charge generating material used for the single-layer photosensitive layer and the laminated charge generating layer in the electrophotographic photosensitive member of the present invention, known materials can be used. For example, amorphous selenium, selenium-tellurium alloy, selenium-arsenic alloy, other selenium compounds and selenium alloys, inorganic photoconductive materials such as zinc oxide, titanium oxide, a-Si, a-SiC, phthalocyanine, squarium Organic pigments and dyes such as, but not limited to, organic pigments, anthrone-based, perylene-based, azo-based, anthraquinone-based, pyrene-based, pyrylium salts, and thiapyrylium salts can be used. Also, these organic pigments and dyes
They can be used alone or in combination of two or more.

The phthalocyanine-based compound has a wavelength of 60 nm, which is the emission wavelength of an LED or a laser diode which is currently used as a light source in a digital electrophotographic apparatus.
Since it has excellent photosensitivity at 0 to 850 nm, it is particularly preferable as the charge generation material of the present invention. Specifically, they are metal-free phthalocyanine and metal phthalocyanine, and the central metals of the metal phthalocyanine include Cu, Ni, Zn, C
o, Fe, V, Si, Al, Sn, Ge, Ti, In,
Examples thereof include Ga, Mg, Pb, and the like, and oxides, hydroxides, halides, alkylates, alkoxylates, and the like of these central metals can also be used. Specific examples include metal-free phthalocyanine, titanyl phthalocyanine, chlorogallium phthalocyanine, hydroxygallium phthalocyanine, vanadyl phthalocyanine, chloroindium phthalocyanine, dichlorotin phthalocyanine, and the like. Further, those having an arbitrary substituent in these phthalocyanine rings can also be used. Further, those in which an arbitrary carbon atom in these phthalocyanine rings is substituted with a nitrogen atom are also effective. As the form of these phthalocyanine compounds, it is possible to use amorphous or all polymorphic forms.

Among these phthalocyanine compounds,
Titanyl phthalocyanine, chlorogallium phthalocyanine, hydroxygallium phthalocyanine, and dichlorotin phthalocyanine have particularly excellent photosensitivity and are particularly preferred as charge generation materials.

The binder resin used for the single-layer type photosensitive layer and the laminate type charge generation layer in the electrophotographic photoreceptor of the present invention includes polyvinyl butyral resin, polyvinyl formal resin, partially modified polyvinyl acetal resin, and polycarbonate resin. , Polyester resin, acrylic resin,
Examples include, but are not limited to, polyvinyl chloride resin, polystyrene resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate copolymer, silicone resin, phenol resin, poly-N-vinyl carbazole resin, and the like. These binder resins can be block, random or alternating copolymers. These binder resins can be used alone or in combination of two or more.

When a plurality of charge transporting layers are used in the photosensitive layer of the present invention, the charge transporting layer which is not the outermost surface may be a known one used as a charge transporting layer in a conventional laminated photoreceptor. . For example, a benzidine-based compound, an amine-based compound, a hydrazone-based compound, a stilbene-based compound, a hole-transporting low-molecular compound such as a carbazole-based compound, or a fluorenone-based compound, a malononitrile-based compound, or an electron-transporting low-molecular-weight compound such as a diphenoquinone-based compound. , Alone or as a mixture of two or more, in the form of a solid solution film in which molecules are uniformly dispersed in an insulating resin such as polycarbonate, polyarylate, polyester, polysulfone, and polymethyl methacrylate, or a polymer that itself has a charge transporting ability Compounds and the like can be used. Also,
An inorganic substance having a charge transporting ability, such as selenium, amorphous silicon, or amorphous silicon carbide, can also be used. Examples of the charge-transporting polymer compound include a polymer compound having a charge-transporting group such as polyvinylcarbazole in the side chain, and a group having a charge-transporting property as disclosed in JP-A-5-232727. And a polysilane having a main chain of Of course, the copolymer of the present invention can be used.

The charge transport layer used in the present invention has a thickness of 1 to 1
The thickness is set to 00 μm, preferably 5 to 50 μm. As a coating method, a usual method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, or the like can be used. In addition, those capable of vapor phase film formation can be directly formed by a vacuum evaporation method or the like.

In the photoreceptor of the present invention, a charge transporting polymer compound is preferably used as the charge transporting substance used in the charge transporting layer in contact with the crosslinked copolymer. The reason is that, in the photoreceptor manufacturing process, when a charge transport layer and a layer containing the copolymer before cross-linking as a main matrix component are laminated and formed, a low molecular weight is added to the charge transport layer in contact with the copolymer before cross-linking. When a charge transporting substance that is a compound is used, the charge transporting low molecular weight compound is mixed in a layer containing a copolymer before cross-linking as a main matrix component, and the insulating property of an insulating phase is reduced, This is because the contaminant molecules serve as charge traps, causing obstacles such as an increase in residual potential, a decrease in transport ability, and a decrease in photosensitivity. This problem is particularly noticeable when each layer is formed by a wet coating method. Of course, these problems can be avoided by selecting an upper layer coating solvent that does not easily dissolve and swell the lower layer, or by selecting an insulating block that is incompatible with the charge transporting low molecular weight compound. It is possible to However, it is known that polymers generally undergo phase separation without being compatible with each other, and a charge transporting polymer compound is used as a charge transport layer in contact with a cross-linked copolymer. In the case, since the phase is separated without being compatible with the insulating block in the cross-linked copolymer, the problem of mixing as described above hardly occurs, and the restriction on the selection of the material and the manufacturing method is eliminated. It has the advantage that.

For the same reason, it is preferable to use a charge-transporting high molecular compound also in the intermediate layer which is in contact with the charge-transport layer containing a crosslinked copolymer as a main matrix component.

In the present invention, when the photoreceptor is composed of a charge transporting layer comprising a copolymer crosslinked with a charge generating layer, an intermediate layer comprising a charge transporting matrix is provided between the charge generating layer and the charge transporting layer. Is preferably provided. Normal,
In the charge generating layer, the charge generating agent is dispersed in a matrix in the form of particles, and the contact between the charge generating particles and the charge transporting block of the crosslinked copolymer in the charge transporting layer causes charge transport. It is smaller than the case where the charge transporting substance in the layer is molecularly dispersed (solid solution) in the matrix. Therefore, between such a charge generation layer and a charge transport layer made of a cross-linked copolymer, a layer in which a charge transport substance is dissolved in a resin matrix, or a layer made of a charge transport polymer. It is preferable to provide an (intermediate layer) to improve the charge transport performance. As the intermediate layer, a known one used as a charge transport layer in a conventional J-shaped laminated photoreceptor can be used. For example, benzidine compounds, amine compounds, hydrazone compounds, stilbene compounds, hole transporting low molecular weight compounds such as carbazole compounds or fluorenone compounds, malononitrile compounds, electron transporting low molecular weight compounds such as diphenoquinone compounds. ,
Alone or in combination of two or more, polycarbonate,
A solid solution film in which molecules are uniformly dispersed in an insulating resin such as polyarylate, polyester, polysulfone, and polymethyl methacrylate, or a polymer compound having a charge transporting ability by itself can be used. Further, an inorganic substance having a charge transporting ability, such as selenium, amorphous silicon, or amorphous silicon carbide, can also be used.
Examples of the charge-transporting polymer compound include a polymer compound having a charge-transporting group such as polyvinylcarbazole in the side chain, and a group having a charge-transporting property as disclosed in JP-A-5-232727. And a polysilane having a main chain of

An electrically inactive region surrounded by a charge transporting matrix may be present in the intermediate layer.

The thickness of the intermediate layer used in the present invention is 0.05
The thickness is set to 10 to 10 μm, preferably 0.1 to 5 μm, and more preferably 0.2 to 2 μm. If the thickness is smaller than the above range, the effect as the intermediate layer is insufficient, and if the thickness is large, the original purpose of the non-uniform charge transport layer tends to be hindered. As a coating method, a usual method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, or the like can be used. In addition, those capable of vapor phase film formation can be directly formed by a vacuum evaporation method or the like.

A protective layer containing a crosslinked copolymer as a main matrix component may be provided on a single-layer type photosensitive layer or a photosensitive layer comprising a charge generation layer and a charge transport layer.
This protective layer protects the photosensitive layer from oxidizing gas such as ozone generated from the charging member, chemical stress such as ultraviolet light, or mechanical stress caused by contact with a developer, paper, a cleaning member, or the like. Is effective for improving the substantial life of the photosensitive layer. In particular, the effect is remarkable in a layer configuration using a thin charge generation layer as an upper layer.

The thickness of the protective layer is suitably from 0.5 to 20 μm, preferably from 1 to 10 μm.

When a protective layer is provided, a blocking layer for preventing leakage of electric charge from the protective layer to the photosensitive layer can be provided between the photosensitive layer and the protective layer, if necessary. As the blocking layer, a known layer can be used.

In the electrophotographic photoreceptor of the present invention, ozone or oxidizing gas generated in the electrophotographic apparatus, or
An antioxidant, a light stabilizer, a heat stabilizer and the like can be added to each layer or the uppermost layer for the purpose of preventing the photoconductor from being deteriorated by light and heat. As the antioxidant, known ones can be used, and examples thereof include hindered phenol, hindered amine, paraphenylenediamine, hydroquinone, spirochroman, spiroidanone and derivatives thereof, organic sulfur compounds, organic phosphorus compounds and the like. . As the light stabilizer, known ones can be used, for example, derivatives such as benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine, and electron withdrawing properties that can deactivate the photoexcited state by energy transfer or charge transfer. And a compound or an electron donating compound.

Further, reduction of surface wear, improvement of transferability,
Insulating particles such as a fluororesin may be dispersed in the outermost surface layer for the purpose of improving the cleaning property and the like.

When the electrophotographic photoreceptor of the present invention is an S-shaped photoreceptor, it is preferable to have the layer structure shown in FIGS. The reason why the photoreceptor having such a configuration exhibits the S-shaped photo-organic potential decay characteristic is not always clear, but it is presumed that the charge transport path is nonlinear due to the non-uniformity of the charge transport layer. (JP-A-9-96914).
In the case of using an S-shaped photoreceptor, the pitch of the charge transporting phase is preferably from 0.01 to 3 μm, more preferably from 0.02 μm.
To 1 μm, particularly preferably 0.05 to 0.5 μm.

The electrophotographic apparatus on which the electrophotographic photosensitive member of the present invention is mounted may be any apparatus using an electrophotographic method. For example, analog exposure type electrophotographic copying machine, laser exposure type digital electrophotographic copying machine,
Electrophotographic facsimile, laser beam printer,
Examples include an LED printer and a liquid crystal shutter printer. Cleaning means together with the electrophotographic photosensitive member,
The device unit may be combined with at least one of a charging unit and a developing unit. Although any developing means may be used for the electrophotographic apparatus, in the electrophotographic apparatus employing the liquid developing method, the electrophotographic photoreceptor of the present invention is excellent in solvent resistance due to crosslinking and has no problem such as cracks. Can be preferably used.

[0102]

The present invention will be specifically described below with reference to examples. However, the present invention is not limited to the following examples, and those skilled in the art can modify the following examples based on known knowledge of electrophotographic technology.

Synthesis Example 1 : Reactive polymerization initiator 4,4′-
Synthesis of azobis (4-cyanovaleric chloride) Thionyl chloride (220 ml) was ice-cooled, and 4,4'-azobis (4-cyanovaleric acid) (100 g) was gradually added. 30 ° C
For 6 hours, and excess thionyl chloride was distilled off under reduced pressure. The residue was recrystallized from chloroform to obtain 42 g of 4,4′-azobis (4-cyanovaleric acid chloride) crystal.

Synthesis Example 2 N, N′-bis (p, m-dimethylphenyl) -N,
100 g of N'-bis [p- (2-methoxycarbonylethyl) phenyl]-[3,3'-dimethyl-1,1'-biphenyl] -4,4'-diamine, 200 g of ethylene glycol and 5 g of tetrabutoxytitanium ,
The mixture was heated and refluxed for 3 hours under a nitrogen stream. N, N'-bis (p, m-dimethylphenyl) -N, N'-bis [p-
(2-methoxycarbonylethyl) phenyl]-[1,
After confirming that 1′-biphenyl] -4,4′-diamine was consumed, the pressure was reduced to 0.5 mmHg, and the mixture was heated to 230 ° C. while distilling off ethylene glycol.
The reaction was continued for hours. Thereafter, the mixture was cooled to room temperature, methylene chloride was added to dissolve the insoluble matter, and the precipitate was reprecipitated from acetone to obtain 90 g of a prepolymer having hydroxy groups at both ends. The weight average molecular weight of the obtained prepolymer was 7.4 × 104.

The above polymer (43 g) and triethylamine (0.5 g) were dissolved in toluene (120 ml) and cooled to 0 ° C. or lower. Here, 5.6 g of 4,4′-azobis (4-cyanovaleric acid chloride) obtained in Synthesis Example 1 was added to toluene 2
The liquid suspended in 0 ml was added dropwise. After reacting at room temperature for 1 hour, the reaction was carried out at 30 ° C. for 6 hours. The solvent was distilled off from this, and it was dissolved by adding tetrahydrofuran, added dropwise to methanol, stirred for 1 hour, and filtered. This reprecipitation operation was repeated twice more. The remaining compound was dried to obtain 41 g of a polymer having an azo-type polymerization initiator at both ends.

6 g of the polymerization initiator-containing polymer, ter
6 g of t-butyl methacrylate and 2 g of 2-hydroxy methacrylate were dissolved in 120 ml of toluene, and the mixture was purged with nitrogen and heated at 65 ° C. for 95 hours. This solution was added dropwise to methanol, stirred for 1 hour, and filtered off. The obtained solid is sufficiently washed with cyclohexane, and a block comprising a charge transporting block having a triarylamine structure and an insulating block having a hydroxy group as a crosslinkable functional group represented by the following structural formula (3): 9 g of copolymer
I got The weight average molecular weight of the obtained copolymer is 12 × 1
0 is ^{4, 1} of the resulting block copolymer H-NMR
From the integral ratio of the peaks corresponding to the protons specific to both blocks in the spectrum, the weight composition ratio of the charge transporting block and the insulating block is calculated to be about 3: 2. Similarly, the weight composition ratio of the crosslinked portion and the non-crosslinked portion in the insulating block is calculated to be about 2: 8.

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Synthesis Example 3 N, N′-bis (p, m-dimethylphenyl) -N,
N′-bis [p- (2-methoxycarbonylethyl) phenyl]-[3,3′-dimethyl-1,1′-biphenyl] -4,4′-diamine is converted to N, N-bis (p, m-
A polymer having an azo-type polymerization initiator at both terminals was obtained in the same manner as in Synthesis Example 2 except that dimethylphenyl) -N-[(m, m'-bismethoxycarbonylethyl) phenyl] amine was used.

6 g of a charge transporting polymer having an azo-type polymerization initiator at both terminals, 6 g of tert-butyl methacrylate, and 2 g of 3-trimethoxysilylpropyl methacrylate were dissolved in 120 ml of tetrahydrofuran. Heated for hours. This solution was added dropwise to methanol, stirred for 1 hour, and filtered off. The obtained solid is sufficiently washed with cyclohexane, and is composed of a charge transporting block having a triarylamine structure and an insulating block having an alkoxysilyl group as a crosslinkable functional group represented by the following structural formula (4). A block copolymer was synthesized. The weight average molecular weight of the charge transporting prepolymer is 3.1 × 10 ⁴ , the weight average molecular weight of the finally obtained block copolymer is 5.5 × 10 ⁴ , and the composition ratio of both blocks is about 2: Calculated as 3. Further, the weight composition ratio of the crosslinked portion and the non-crosslinked portion in the insulating block is calculated to be about 2: 8.

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Synthesis Example 4 Copolymers having different composition ratios were synthesized in the same manner as in Synthesis Example 2 except that the mixing ratio of each material was changed. The composition ratio between the charge transporting block and the insulating block is calculated to be about 2: 3. Further, the weight composition ratio of the crosslinked portion and the non-crosslinked portion in the insulating block is calculated to be about 2: 8.

Synthesis Example 5 Copolymers having different composition ratios were synthesized in the same manner as in Synthesis Example 3 except that the mixing ratio of each material was changed. The composition ratio between the charge transporting block and the insulating block is calculated to be approximately 1: 4. Further, the weight composition ratio of the crosslinked portion and the non-crosslinked portion in the insulating block is calculated to be about 2: 8.

Example 1 To a solution prepared by dissolving 8 parts by weight of the block copolymer obtained in Synthesis Example 5 in 90 parts of toluene was added 2 parts by weight of chlorogallium phthalocyanine, and the mixture was dispersed with stainless beads by a ball mill for 48 hours. After that, acetic acid 0.1%
The coating liquid was prepared by adding parts by weight. This coating solution was applied on an aluminum plate by a dip coating method, and 135
The composition was cured by heating at 60 ° C. for 60 minutes to prepare a single-layer type electrophotographic photosensitive member having a thickness of 20 μm.

When the photosensitive layer was observed with a transmission electron microscope using a ruthenic acid staining method, a phase-separated structure was observed. The scale of the phase separation structure is about 0.03 μm.
Met.

The electrophotographic photoreceptor thus obtained
To the electrostatic copying paper tester (electrostatic
Analyzer EPA-8100, manufactured by Kawaguchi Electric Works, Ltd.)
Under the environment of normal temperature and normal humidity (20 ° C., 40% RH),
Evaluation of electrophotographic properties was performed. Adjust corona discharge voltage
After charging the photoconductor surface to 750V, the interference filter
Halogen lamp light monochromaticized to 750 nm
2 mW / m on photoreceptor surface^TwoAdjust the light intensity to
And irradiate for 7 seconds.
E_50%I asked. Also, the potential 7 seconds after the start of the exposure is left.
The residual potential was used. E _50%Is 4.2 mJ / m^Two, The residual potential is
It was 50V.

Further, an electrophotographic photosensitive member was manufactured in the same manner as described above except that an aluminum drum was used instead of the aluminum substrate, and a laser printer (Laser Printer) was used.
Press 4105, manufactured by Fuji Xerox Co., Ltd.). Since this laser printer was for a negatively charged photoreceptor, it was modified for a positively charged photoreceptor, and a 30,000-sheet running test on an actual machine was performed. The difference between the film thickness of the photosensitive layer after the 30,000 sheet running test and the film thickness before the actual machine running was taken as the abrasion loss. The wear amount was 0.9 μm.

Comparative Example 1 To a solution in which 8 parts by weight of a polycarbonate Z resin (Iupilon Z-400, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was previously dissolved in 90 parts of toluene, 2 parts by weight of chlorogallium phthalocyanine was added. Dispersion treatment was performed for 48 hours to prepare a coating solution. The obtained coating solution was applied by dip coating on an aluminum plate and an aluminum drum, and was dried by heating at 100 ° C. for 1 hour.
A single-layer type electrophotographic photoreceptor having the above photosensitive layer was prepared.
As a result of evaluation in the same manner as in Example 1, E _50% was 8 mJ /
m ² .

Comparative Example 2 Compound represented by Structural Formula (5) as a low-molecular charge transport material
A photoconductor was prepared in the same manner as in Comparative Example 1, except that 5 parts by weight was added.
And evaluated in the same manner as in Example 1. As a result, E _50%Is
3.6mJ / m^TwoAnd the residual potential was 40V. Also,
An actual machine running test was performed in the same manner as in Example 1. The wear amount is 5.
It was 5 μm.

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By comparing Example 1 with Comparative Examples 1 and 2, it can be seen that the copolymer effectively contributes to charge transport. In addition, by comparing Example 1 and Comparative Example 2,
It can be seen that the abrasion resistance is greatly improved.

Example 2 20 parts by weight of a zirconium alkoxide compound (trade name: ORGATICS ZC540, manufactured by Matsumoto Pharmaceutical Co., Ltd.) and γ-aminopropyltriethoxysilane (trade name) were placed on an aluminum plate and a honed aluminum drum. : A1100, manufactured by Nippon Unicar)
2 parts by weight and polyvinyl butyral resin (Eslec B
(MS, manufactured by Sekisui Chemical Co., Ltd.) A solution consisting of 1.5 parts by weight of n-butanol and 70 parts by weight of n-butanol was applied by a dip coating method, and heated and dried at 170 ° C. for 10 minutes.
An undercoat layer of 0 μm was formed. Next, 4 parts by weight of chlorogallium phthalocyanine microcrystals were mixed with 2 parts by weight of a vinyl chloride-vinyl acetate copolymer (trade name: UCAR Solution Vinyl Resin VMCH, manufactured by Union Carbide), 67 parts by weight of xylene, and 33 parts by weight of butyl acetate. Mixed with
2 with a sand grinder together with 1mmφ glass beads
After dispersing by time treatment, the obtained coating solution was applied on the undercoat layer by a dip coating method, and dried by heating at 100 ° C. for 10 minutes to form a 0.2 μm-thick charge generating layer.

Next, 10 parts by weight of the block copolymer obtained in Synthesis Example 2 and 1 part by weight of a trivalent isocyanate compound represented by the following structural formula (6) as a crosslinking agent were dissolved in 90 parts by weight of cyclohexanone. After the solution was applied on the charge generation layer by a dip coating method,
The resultant was cured by heating for 20 minutes to form a charge transport layer having a thickness of 20 μm, thereby producing an electrophotographic photosensitive member shown in FIG.

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When the photosensitive layer was observed with a transmission electron microscope using a ruthenic acid staining method, a phase-separated structure was observed. The scale of the phase separation structure is about 0.06 μm
Met. The evaluation was performed in the same manner as in Example 1 except that the charging polarity of the electrophotographic photosensitive member thus obtained was negative. E _50% is 4.5 mJ / m ² , residual potential is −60
V, E _50% / E _{10% The} value was 1.8, which was an S-shape. An actual machine running test was performed in the same manner as in Example 2 except that the photoconductor was not modified for a positively charged photoconductor. The wear amount is 0.6μm
Met.

Comparative Example 3 In the same manner as in Example 2, a charge generation layer was formed. Next, 20 parts by weight of a compound composed of a repeating unit represented by the following structural formula (7) having a molecular weight of 80,000, which is a polymer charge transporting material, is dissolved in 80 parts by weight of monochlorobenzene, and immersion coating is performed on the charge generation layer. And dried by heating at 135 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm, thereby producing an electrophotographic photoreceptor. The electrophotographic photosensitive member thus obtained was subjected to an actual running test in the same manner as in Example 2. As a result, the abrasion amount was 1.0 μm.

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Example 3 To a solution in which 8 parts by weight of a polycarbonate Z resin (Iupilon Z-400, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was previously dissolved in 89 parts of toluene, 3 parts by weight of dichlorotin phthalocyanine was added, and the mixture was sand-milled for 24 hours. It was dispersed to prepare a coating liquid.
The obtained coating solution was applied onto an aluminum plate and an aluminum drum by dip coating, and dried by heating at 100 ° C. for 1 hour to prepare a photosensitive layer having a thickness of 15 μm. Next, 8 parts by weight of the copolymer of Synthesis Example 3 was dissolved in 92 parts by weight of toluene, and a coating solution containing 0.5 part by weight of acetic acid was further spray-coated on the photosensitive layer. It was cured by heating to form a surface protective layer having a thickness of 3 μm, and an electrophotographic photosensitive member having a structure shown in FIG. 9 was formed.

When this protective layer was observed with a transmission electron microscope using a ruthenic acid staining method, a phase-separated structure was observed. Also, the scale of the phase separation structure is about 0.03μ.
m. When the electrophotographic photoreceptor thus obtained was evaluated in the same manner as in Example 2, the E _50% was 6.5 m.
J / m ² , and the residual potential was −90 V. Further, a running test of the actual machine was performed in the same manner as in Example 2, and the amount of wear was found to be 0.3.
It was 5 μm.

Example 4 In the same manner as in Example 3, an undercoat layer and a charge generation layer were applied on an Al plate. Next, a polymer having a molecular weight of 8
Twenty parts by weight of a compound consisting of 10,000 units of the repeating unit represented by the structural formula (7) is dissolved in 80 parts by weight of monochlorobenzene, applied on the charge generation layer by a dip coating method, and dried by heating at 135 ° C. for 1 hour. And a film thickness of 20
A μm charge transport layer was formed. Next, 10 parts by weight of the block copolymer obtained in Synthesis Example 4 and a trivalent isocyanate compound represented by the structural formula (6) 1.
A solution prepared by dissolving 5 parts by weight of cyclohexanone in 90 parts by weight was applied on the charge transport layer by dip coating, and then heated and cured at 150 ° C. for 60 minutes to form a film having a thickness of 2 μm.
m, and an electrophotographic photoreceptor having the structure shown in FIG. 15 was formed.

When this protective layer was observed with a transmission electron microscope using a ruthenic acid staining method, a phase-separated structure was observed. The scale of the phase separation structure is about 0.06μ.
m. When the electrophotographic photoreceptor thus obtained was evaluated in the same manner as in Example 2, the E _50% was 4.5 m.
J / m ² , and the residual potential was −60V. Further, a running test of the actual machine was performed in the same manner as in Example 2, and the amount of wear was found to be 0.3.
It was 5 μm.

Example 5 In the same manner as in Example 2, a charge generation layer was formed. Next, 12 parts by weight of a compound composed of a repeating unit represented by the structural formula (7) having a molecular weight of 80,000, which is a polymer charge transporting material, is dissolved in 88 parts by weight of monochlorobenzene, and dip coating is performed on the charge generation layer. And at 135 ° C for 10
After drying for 2 minutes, an intermediate layer having a thickness of 2 μm and comprising a charge transporting matrix was formed. Further, on this intermediate layer, 18 parts by weight of the block copolymer obtained in Synthesis Example 3 was dissolved in 82 parts of toluene, 1 part by weight of acetic acid was further added, and a coating solution was applied by an applicate method. At 6
By heating and curing for 0 minutes to form a charge transport layer having a thickness of 20 μm, an electrophotographic photosensitive member shown in FIG. 8 was produced.

The electrophotographic photoreceptor thus obtained was evaluated in the same manner as in Example 2. As a result, E _50% was 3.4 m.
It was an S-shape having J / m ² , a residual potential of −30 V, and an E _50% / E _10% value of 2.4.

[0128]

The electrophotographic photoreceptor of the present invention comprises an electrophotographic photoreceptor having a photosensitive layer containing a charge generation material and a charge transport material on at least a conductive substrate. The structure contains a copolymer consisting of a three-dimensional charge transport block and an insulating block, and the copolymer is separated into a charge transport phase and an insulating phase. It is possible to provide an electrophotographic photoreceptor that is excellent in abrasion resistance during use, has low residual potential, and is excellent in high-speed response.

Further, after applying a coating liquid containing a block copolymer or a graft copolymer composed of a charge transporting block having a crosslinkable functional group whose molecular structure is not three-dimensional and an insulating block. The above-mentioned electrophotographic photoreceptor is provided by a method for producing an electrophotographic photoreceptor, wherein the molecular structure of the block copolymer or the graft copolymer is made three-dimensional by crosslinking at the same time as or when the coating is applied. it can.

Furthermore, by providing such an electrophotographic photosensitive member having excellent charge transporting ability and excellent mechanical properties, it is possible to provide an electrophotographic apparatus and an apparatus unit which are excellent in repetition stability and reliability. Can be.

[0131]

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a single-layer type photoreceptor.

FIG. 2 is a schematic cross-sectional view showing an example of a single-layer type photoreceptor having an undercoat layer.

FIG. 3 is a schematic cross-sectional view illustrating an example of a laminated photoconductor.

FIG. 4 is a schematic cross-sectional view illustrating an example of a laminated photoconductor having an undercoat layer.

FIG. 5 is a schematic cross-sectional view showing an example of a laminated photoreceptor having two charge transport layers.

FIG. 6 is a schematic cross-sectional view of the laminated type photoreceptor of FIG. 5 further having an undercoat layer.

FIG. 7 is a schematic cross-sectional view illustrating an example of a laminated photoconductor having an intermediate layer.

FIG. 8 is a schematic cross-sectional view of the laminated photoreceptor of FIG. 7 further having an undercoat layer.

FIG. 9 is a schematic cross-sectional view showing an example of a single-layer type photoconductor provided with a protective layer.

FIG. 10 is a schematic cross-sectional view illustrating an example of a laminated photoconductor provided with a protective layer.

FIG. 11 is a schematic cross-sectional view showing another example of a laminated photoconductor provided with a protective layer.

FIG. 12 is a schematic cross-sectional view illustrating an example of a single-layer type photoconductor provided with an undercoat layer and a protective layer.

FIG. 13 is a schematic cross-sectional view showing an example of a laminated photoconductor provided with an undercoat layer and a protective layer.

FIG. 14 is a schematic cross-sectional view showing another example of a laminated photoconductor provided with an undercoat layer and a protective layer.

FIG. 15 is a graph showing a relationship between an exposure amount and a surface potential in a J-shaped electrophotographic photosensitive member.

FIG. 16 is a graph showing a relationship between an exposure amount and a surface potential in an S-shaped electrophotographic photosensitive member.

[Explanation of symbols]

 1: conductive support 2: photosensitive layer 3: undercoat layer 4: charge generation layer 5: charge transport layer 6: first charge transport layer 7: second charge transport layer 8: intermediate layer 9: surface protective layer

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Masakazu Iijima 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Taketoshi 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Fuji Xerox Co., Ltd.

Claims (16)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer containing a charge generating material and a charge transporting material on at least a conductive substrate, wherein the charge transporting material has at least a three-dimensional molecular structure by crosslinking. An electrophotographic photoreceptor comprising a copolymer containing a charge transport block and an insulating block, wherein the charge transport phase and the insulating phase of the copolymer are phase-separated. . 2. A three-dimensional molecular structure by crosslinking.
2. The electrophotographic photoreceptor according to claim 1, wherein a cross-linking site in the copolymer containing the charge transport block and the insulating block mainly exists in the insulating block. 3. A three-dimensional molecular structure by crosslinking.
2. The repeating unit of the charge transporting block in the copolymer containing the charge transporting block and the insulating block contains at least a repeating unit having a triarylamine structure. Item 3. The electrophotographic photosensitive member according to Item 2. 4. The electrophotographic photosensitive material according to claim 3, wherein the charge transporting block having a triarylamine structure has at least one of the structures represented by the following general formula (1) as a repeating unit. body. Embedded image (Wherein, Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group, X ¹ is a divalent hydrocarbon group or a hetero atom-containing hydrocarbon group having an aromatic ring structure, X ² And X ³ each independently represent a substituted or unsubstituted arylene group; L ¹ represents a divalent hydrocarbon group or a heteroatom-containing hydrocarbon group which may have a branched or ring structure; , 0 or 1 respectively
Means an integer selected from ) 5. The electrophotographic photosensitive member according to claim 4, wherein X ¹ in the general formula (1) is a substituted or unsubstituted biphenylene group. 6. The electrophotographic photosensitive material according to claim 3, wherein the charge transporting block having a triarylamine structure has at least one of the structures represented by the following general formula (2) as a repeating unit. body. Embedded image (In the formula, Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group, and L ² represents a trivalent hydrocarbon group having an aromatic ring structure or a heteroatom-containing hydrocarbon group.) 7. The electrophotographic photosensitive member according to claim 1, wherein the insulating block comprises a polymer of a vinyl monomer. 8. The vinyl monomer contains at least one kind of a compound represented by the following general formula (3) and at least one kind of a compound having a crosslinkable functional group represented by the following general formula (4). The electrophotographic photosensitive member according to claim 7, wherein: Embedded image (Wherein, R ^{1 to} R ³ each independently represent a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group or an aryl group, and R ⁴ represents a halogen atom, or a substituted or unsubstituted alkyl group or an aryl group. , An alkoxy group, an acyl group, an acyloxy group, or an alkoxycarbonyl group.) (Wherein, R ^{5 to} R ⁷ each independently represent a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl or aryl group, and R ⁸ represents a chlorosulfone group, a carboxyl group, a hydroxy group, a mercapto group, a nitrile Represents an alkyl group, an aryl group, an alkoxy group, an acyl group, an acyloxy group, or an alkoxycarbonyl group substituted with a group, an isocyanate group, an amino group, an epoxy group or an alkoxysilyl group.) 9. The cross-linked polymer of a block copolymer or a graft copolymer having a charge-transportable block and an insulating block, which has a crosslinkable functional group. 2. The electrophotographic photosensitive member according to 1. 10. A copolymer having a charge transporting block and an insulating block, the molecular structure of which is three-dimensionalized by crosslinking, comprising a copolymer having a hydroxy group and comprising a charge transporting block and an insulating block. 2. The electrophotographic photoconductor according to claim 1, wherein the electrophotographic photoconductor is a crosslinked polymer of a polyvalent isocyanate compound. 11. A copolymer having a charge transporting block and an insulating block, the molecular structure of which has been made three-dimensional by cross-linking, wherein the functional groups in the copolymer comprising the charge transporting block and the insulating block are different from each other. The electrophotographic photoreceptor according to claim 1, wherein the electrophotographic photoreceptor is a crosslinked polymer obtained by a condensation reaction of 12. A copolymer having a charge transporting block and an insulating block, the molecular structure of which is three-dimensionally formed by crosslinking, comprising an alkoxysilyl group and comprising a charge transporting block and an insulating block. The electrophotographic photoreceptor according to claim 1, which is a crosslinked polymer of 13. The exposure amount required for 50% potential decay is 10
13. The electrophotographic photoreceptor according to claim 1, wherein the exposure amount is less than 5 times the amount of exposure required for% potential decay. 14. A coating liquid containing a block copolymer or a graft copolymer having a charge-transportable block and an insulating block, which does not have a three-dimensional molecular structure and has a crosslinkable functional group, is applied. A method for producing an electrophotographic photoreceptor, wherein the molecular structure of the block copolymer or the graft copolymer is made three-dimensional by crosslinking after or simultaneously with the coating. 15. A crosslinkable functional group in a block copolymer or a graft copolymer having a charge transport block and an insulating block, which has a crosslinkable functional group whose molecular structure is not three-dimensional. The method for producing an electrophotographic photoreceptor according to claim 14, wherein the photoreceptor is mainly present in an insulating block. 16. An electrophotographic apparatus comprising the electrophotographic photoreceptor according to claim 1. Description: