JP2002131941A - Electrophotographic photoreceptor, and process cartridge and electrophotographic device having the electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor having an excellent mechanical strength and surface lubricating property after the photoreceptor is used for a long time, and to provide an electrophotographic photoreceptor having good electrophotographic characteristics and good coating property and a long pot life of the coating material in the manufacture process and hardly causing a distortion or an abnormal noise even in a general cleaning blade. SOLUTION: In the electrophotographic photoreceptor having a supporting body and a photosensitive layer, the surface layer of the electrophotographic photoreceptor contains a polyarylate having a repeating unit of a specified structure, a polycarbonate having a repeating unit of a specified structure, a copolymer having two kinds of repeating units of specified structures, a copolymer having three kinds of repeating units of specified structures, and a graft polymer having polymerizable monomers with silicon atoms in the side chains as the structural component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member, and more particularly, to an electrophotographic photosensitive member having a photosensitive layer containing a specific resin on a surface layer, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic photosensitive member. Related to the device.

[0002]

2. Description of the Related Art An electrophotographic method is disclosed in U.S. Pat.
As shown in the specification, a photoconductive material is used in which the electric resistance changes according to the amount of irradiation received during exposure and which is made of a support coated with an insulating substance in a dark place.
The basic characteristics required of an electrophotographic photoreceptor using this photoconductive material include (1) being able to be charged to an appropriate potential in a dark place, (2) being small in potential dissipation in a dark place, (3) Quickly dissipating the charge by light irradiation.

Heretofore, as an electrophotographic photosensitive member, an inorganic photosensitive member having a photosensitive layer containing an inorganic photoconductive compound such as selenium, zinc oxide and cadmium sulfide as a main component has been widely used. However, they satisfy the above conditions (1) to (3), but are not always satisfactory in heat stability, moisture resistance, durability, and productivity. In recent years, electrophotographic photoconductors containing various organic photoconductive compounds as main components have been actively developed in order to overcome the disadvantages of inorganic photoconductors. For example, U.S. Pat. No. 3,838,851 discloses a photoreceptor having a charge transport layer containing triallylpyrazoline, U.S. Pat. No. 3,871,880 describes a charge generating layer comprising a derivative of a perylene pigment, and a charge generating layer comprising 3-propylene and formaldehyde. A photoreceptor comprising a charge transport layer comprising a condensate is known.

Further, the photosensitive wavelength range of the electrophotographic photosensitive member can be freely selected by the organic photoconductive compound depending on the compound.
The substances disclosed in JP-A-272754 and JP-A-56-167759 disclose substances exhibiting high sensitivity in the visible region, and are disclosed in JP-A-57-19576 and JP-A-61-228453. It has been shown that the compounds described in the publication have sensitivity up to the infrared region. Among these materials, those exhibiting sensitivity in the infrared region are used in laser beam printers (hereinafter abbreviated as LBPs) and LED printers, which have been making remarkable progress in recent years, and the demand frequency thereof is increasing.

Electrophotographic photoreceptors using these organic photoconductive compounds are function-separated type photoreceptors in which a charge transport layer and a charge generation layer are laminated in order to satisfy both electrical and mechanical properties. Often used. On the other hand, as a matter of course, the electrophotographic photoreceptor is required to have sensitivity, electric characteristics, and optical characteristics according to the applied electrophotographic process. Particularly in the electrophotographic photoreceptor that is used repeatedly, the surface of the electrophotographic photoreceptor is directly applied with electrical or mechanical external force such as corona or contact charging, exposure, toner development, transfer process, surface cleaning, etc. Durability against them is also required.

More specifically, electrical deterioration due to ozone and nitrogen oxides during charging, electric discharge during charging, mechanical deterioration in which the surface is worn or scratched due to rubbing of a cleaning member, Durability against electrical degradation is required. The electrical deterioration is particularly problematic in that carriers stay in a portion irradiated with light and an electric difference occurs in a portion not irradiated with light, which occurs as a photo memory. The mechanical deterioration is particularly different from the inorganic photoreceptor, and the organic photoreceptor having many soft materials is inferior in the durability against the mechanical deterioration, and the improvement of the durability is particularly desired. Various attempts have been made to satisfy the durability characteristics required for the photosensitive member as described above.

As a resin which is often used for the surface layer and has excellent abrasion and electrical properties, attention has been paid to a polycarbonate resin having bisphenol A as a skeleton. However, not all of the above problems can be solved. In addition, it has the following problems.

(1) It has poor solubility, shows good solubility only in a part of halogenated aliphatic hydrocarbons such as dichloromethane and 1,2-dichloroethane, and has a low boiling point because these solvents have a low boiling point. When a photoreceptor is manufactured using a coating solution prepared with these solvents, the coated surface tends to be whitened. It takes time to control the solid content of the coating liquid.

(2) It is partially soluble in solvents other than halogenated aliphatic hydrocarbons in tetrahydrofuran, dioxane, cyclohexanone or a mixed solvent thereof, but the solution gels in a few days. It has poor aging properties and is not suitable for photoconductor production.

(3) Further, even if the above (1) and (2) are improved, solvent cracks are liable to occur in the polycarbonate resin having bisphenol A as a skeleton.

(4) In addition, in the conventional polycarbonate resin, since the coating formed of the resin does not have lubricity, the photosensitive member is easily damaged, and cleaning is performed so as to reduce the abrasion amount of the electrophotographic photosensitive member. The setting may cause an image defect, cleaning failure due to early deterioration of the cleaning blade, toner fusion, and the like.

Regarding the solution stability mentioned in the above (1) and (2), use of a polycarbonate Z resin having a cyclohexylene group as a structural unit of the polymer, or copolymerization with bisphenol Z, bisphenol C, etc. It has been solved by

On the other hand, polyarylate has a structure similar to that of polycarbonate, but differs in various properties. For example, although the mechanical strength is superior, the solubility of the Z type having a cyclohexylidene group is low. In addition, there are differences in electrophotographic photoreceptor characteristics, and particularly when used as a binder resin for a charge transport layer, each memory, residual potential, and the like are susceptible to change (deterioration) depending on the structure of the charge transport material used. .

In addition, the coating film formed is harder than conventional polycarbonate resins, so that the formed coating is hard to be scraped off. With a general cleaning method using a rubber blade, the surface is rougher than polycarbonate and the contact area increases, so that the cleaning blade is brought into contact with the cleaning blade in the counter direction. In such a case, the phenomenon that the cleaning blade is turned up easily occurs.

As for the solvent crack, as disclosed in JP-A-6-51544, JP-A-6-75415, and JP-A-6-295075, a silicon-modified polycarbonate and an ether-modified polycarbonate are used. It is possible to solve the problem. However, compared to conventional polycarbonate resins, these modified polycarbonates have a structure that gives flexibility to internal stress in the polymer in order to prevent solvent cracks, and as a result, the mechanical There was a disadvantage that the strength was reduced.

In recent years, contact charging in which a voltage is applied directly to a charging member to apply a charge to an electrophotographic photosensitive member as disclosed in JP-A-57-17826 and JP-A-58-40566. The method is becoming mainstream. This is a method in which a roller-shaped charging member made of conductive rubber or the like is brought into direct contact with an electrophotographic photoreceptor to apply an electric charge. Compared to a scorotron or the like, the amount of generated ozone is remarkably small. Is 80 of the current flowing through the charger.
While around% is wasted because it flows to the shield,
Contact charging has such advantages that it is very economical without this waste.

[0017]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problem of having a conventional polycarbonate resin or polyarylate resin as a surface layer, and to improve the mechanical strength and lubricity. An object of the present invention is to provide an electrophotographic photoreceptor which has both of them until the end of the life. Further, an electrophotographic photoreceptor having good electrophotographic properties, good coatability during coating and good coating pot life, and which does not generate curling or abnormal noise even with a general cleaning blade is provided. It is.

[0018]

According to the present invention, in an electrophotographic photosensitive member having a support and a photosensitive layer, the surface layer of the electrophotographic photosensitive member comprises the following components (A) to (E): ) A polyarylate having a repeating unit represented by the following formula (1); (B) a polycarbonate having a repeating unit represented by the following formula (2); and (C) a repeating unit represented by the following formulas (3) and (4). (D) a copolymer having repeating units represented by the following formulas (5), (6) and (7), and (E)
An electrophotographic photoreceptor characterized by comprising a graft polymer having a polymerizable monomer having a silicon atom in a side chain as a constituent component.

[0019]

[Outside 8]

(X ₁ is a carbon atom or a single bond (R ₅ and R ₆ are not used in this case), R _{1 to} R ₄ are a hydrogen atom, a halogen atom, an alkyl group which may be substituted, And R ₅ and R ₆ each represent a hydrogen atom, a halogen atom, an alkyl group which may be substituted, an aryl group which may be substituted, or a substituent formed by bonding R ₅ and R _6. Indicates an alkylidene group which may be
R ₇ to R ₁₀ are each a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an optionally substituted aryl group).

[0021]

[Outside 9]

[0022]

[Outside 10]

[0023]

[Outside 11]

[0024]

[Outside 12]

[0025]

[Outside 13]

[0026]

[Outside 14]

Wherein R _{37 to} R ₃₈ are an alkylene group or an alkylidene group having 1 to 6 carbon atoms, and R _{39 to} R ₄₂ are a group having 1 carbon atom.
An alkyl group, a phenyl group or a substituted phenyl group,
n represents an integer of 1 to 200).

According to the present invention, the electrophotographic photosensitive member and at least one unit selected from the group consisting of a charging unit, a developing unit and a cleaning unit are integrally supported and detachably attached to an electrophotographic apparatus main body. A process cartridge is provided.

Further, according to the present invention, there is provided an electrophotographic apparatus comprising the above electrophotographic photosensitive member, charging means, exposure means, developing means and transfer means.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION In the formulas (1) to (7), examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom, and examples of the alkyl group include a lower alkyl group such as a methyl group and an ethyl group. A propyl group, a butyl group and the like are mentioned, an aryl group is a phenyl group, a naphthyl group and the like, and a cycloalkylidene group is a cyclohexylidene group and the like. Examples of the substituent which the alkyl group, the aryl group and the cycloalkylidene group may have include a lower alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group; an aryl group such as a phenyl group and a naphthyl group; And a halogen atom such as a chlorine atom and a bromine atom. n represents a positive integer;
It is preferably 0.

Preferred specific examples of the repeating unit represented by the formula (1) are shown in Table 1, but the present invention is not limited to these. Among these, examples of the repeating unit (1-1), (1-2) and (1-23) are particularly preferable, and examples of the repeating unit (1-2) are more preferable.

[0032]

[Table 1]

[0033]

[Table 2]

[0034]

[Table 3]

[0035]

[Table 4]

The polymer having a repeating unit represented by the formula (1) used in the present invention is usually mixed with a mixture of terephthalic acid chloride and isophthalic acid chloride and various bisphenols for controlling solubility and rigidity. Are interfacially polymerized with stirring in a solvent / water system under an alkali. That is, the formula shown in Table 1 was expressed as a form prepared from a mixed system of terephthalic acid chloride and isophthalic acid chloride. However, the ratio of terephthalic acid chloride and isophthalic acid chloride is determined in consideration of the solubility of the polymer, and there is no established theory. However, care must be taken when the content of any of the chlorides is 30 mol% or less, since the solubility of the synthesized polymer is extremely reduced. Usually 1
It is preferable to synthesize at a ratio of / 1. In the electrophotographic photoreceptor of the present invention, even if a monopolymer is composed of the same repeating unit represented by the formula (1), a copolymer comprising two or more different kinds of the repeating units represented by the formula (1) may be used. It may be a polymer.

Preferred specific examples of the repeating unit represented by the formula (2) are shown in Table 2, but the present invention is not limited to these. Among these, the repeating unit examples (2-1), (2-2) and (2-13) are particularly preferred, and the repeating unit example (2-13) is more preferred.

[0038]

[Table 5]

[0039]

[Table 6]

[0040]

[Table 7]

Preferred specific examples of the repeating unit represented by the formula (3) are shown in Table 3. Among these, the repeating unit examples (3-1) and (3-6) are particularly preferable.

[0042]

[Table 8]

[0043]

[Table 9]

Preferable specific examples of the repeating unit represented by the formula (4) are shown in Table 4, but are not limited thereto. Among these, particularly, the repeating unit example (4-
1), (4-2), (4-8), (4-9), (4-1)
0) and (4-13) are preferable, and a repeating unit example (4-13) is more preferable.

[0045]

[Table 10]

[0046]

[Table 11]

[0047]

[Table 12]

Preferred specific examples of the repeating unit represented by the formula (5) are shown in Table 5, but are not limited thereto. Among these, in particular, the repeating unit examples (5-
1), (5-2), and (5-5) are preferable, and a repeating unit example (5-1) is more preferable.

[0049]

[Table 13]

Preferable specific examples of the repeating unit represented by the formula (6) are shown in Table 6, but are not limited thereto. Among these, in particular, the repeating unit example (6-1)
And (6-2) are preferable, and a repeating unit example (6-1) is more preferable.

[0051]

[Table 14]

Preferable specific examples of the repeating unit represented by the formula (7) are shown in Table 7, but are not limited thereto. Among these, in particular, the repeating unit example (7-1),
(7-6) is preferred.

[0053]

[Table 15]

[0054]

[Table 16]

The copolymer having the repeating units represented by the formulas (3) and (4) used in the present invention comprises a bisphenol represented by the following formula (8) and a copolymer represented by the following formula (9)
Is interfacially polymerized in the presence of phosgene, carbonate or chloroformate.

[0056]

[Outside 15]

Wherein X ₄ and R _{49 to} R ₅₄ are represented by the formula (4)
Has the same meaning as X ₃ and R _{23 to} R ₂₈ . The copolymer having the repeating units represented by the formulas (5), (6) and (7) used in the present invention comprises bisphenols represented by the following formulas (10) and (11) and the following formula ( The bisphenol represented by 12) can be obtained by interfacial polymerization in the presence of phosgene, carbonate or chloroformate.

[0058]

[Outside 16]

In the electrophotographic photoreceptor of the present invention, when the mass of the repeating unit represented by the formula (4) is α, and the repeating unit represented by the formula (3) is β, β /
The value of (α + β) is preferably in the range of 0.001 to 0.9, and particularly preferably in the range of 0.001 to 0.2.

In the electrophotographic photoreceptor of the present invention, when the mass of the repeating unit represented by the formulas (5) and (6) is α and the repeating unit represented by the formula (7) is β, β The value of / (α + β) is preferably in the range of 0.001 to 0.9, and particularly preferably in the range of 0.001 to 0.2.

In the formulas (3) and (7), n represents an integer of 1 to 200, and particularly preferably 5 to 100. R ₁₇ and R ₁₈ in the formula (3) and R ₃₇ and R ₃₈ in the formula (7) include methylene, ethylene, propylene, isopropylene, butylene and pentylene, and particularly, methylene, ethylene, propylene and isopropylene. Is preferred.

The graft polymer having a polymerizable monomer having a silicon atom in the side chain as the component (E) used in the present invention is a polymer having a silicon atom in the side chain and a polymerizable terminal. Macromonomer consisting of a monomer having a functional group and a polymerizable monomer having no silicon atom or a relatively low molecular weight oligomer having a polymerizable functional group at a terminal and having a molecular weight of about 1,000 to 10,000 And a structure in which a side chain containing a silicon atom is suspended in a branch from the main chain.

Specific examples of the polymerizable monomer having a silicon atom in the side chain are shown in Table 8, but are not limited thereto.

[0064]

[Table 17]

[0065]

[Table 18]

One of the polymerizable monomers or macromonomers is selected to have an affinity for the resin to which the graft polymer is to be added. For example, acrylates, methacrylates, styrene and styrene derivatives Are used. The copolymerization ratio is preferably 5% by mass or more as the content of the polymerizable monomer having a silicon atom in the side chain. The molecular weight of the obtained polymer is from 500 to 100,000, especially from 1,000 to 50,000 as a weight average molecular weight.
00 is preferred.

Although the detailed mechanism has not been fully elucidated, polyarylate having a repeating unit represented by the formula (1), polycarbonate having a repeating unit represented by the formula (2), and A copolymer having repeating units represented by 3) and (4) and a copolymer having repeating units represented by formulas (5), (6) and (7) are mixed and used. And (E) a graft polymer having a polymerizable monomer having a silicon atom in a side chain as a component, thereby stably improving surface lubricity and solvent crack resistance from the initial stage to the end of the endurance. Can be improved.

It is known that a graft polymer having a polymerizable monomer having a silicon atom in a side chain as a component has a high surface migration property. Therefore, a polymerizable monomer having an added silicon atom in a side chain is known. It can be predicted that most of the graft polymer having a monomer as a constituent component will be localized near the film surface to improve the surface lubricity in the early stage of the durability, but in the configuration according to the present invention, the initial stage of the durability and the The surface lubricity has been improved stably up to now. This is because polyarylate structure, polycarbonate structure, siloxane structure and C
A polycarbonate structure having an F ₃ group penetrates between each molecular chain to break down each crystallinity, and further, a graft polymer having a polymerizable monomer having a silicon atom in a side chain as a constituent is only in the vicinity of the film surface. However, by being present inside the film, a molecular group including a graft polymer having a polymerizable monomer having a silicon atom in a side chain as a constituent component inside the film and an intramolecular orientational order are created, thereby providing high resistance. It is presumed that high surface lubricity and solvent crack resistance up to the end of the durability can be improved while maintaining abrasion.

This effect can be obtained by using a polyarylate structure, a polycarbonate structure, a siloxane structure, a polycarbonate structure having a CF ₃ group, and a polymerizable monomer having a silicon atom in a side chain, which are constituents of the present invention. It is effectively expressed when all the graft polymers having it are complete.Even if one of the constituent elements is missing, the effect is greatly impaired. The lubricating matter of the graft polymer having a polymerizable monomer in the chain as a constituent component, a new effect far exceeding the solvent crack resistance, is exhibited by the interaction between the above-described components of the present invention. It is assumed that

The detailed mechanism is not fully understood.
Although it has not come, R in the formula (1)₁, R_Two, R_Five, R₆
Is a methyl group and R_Three, R_Four , R₇~ R_TenIs a hydrogen atom
Containing a polyarylate having repeating units
And R in equation (2)₁₁~ R ₁₄Is a hydrogen atom
R_Fifteen, R₁₆Is X_TwoTogether with a cyclohexylidene group
Containing polycarbonate having repeating units,
And R in equation (3)₁₇~ R ₂₀Is a methyl group
R_{twenty one}, R_{twenty two}Is a hydrogen atom, and R in the formula (4)_{twenty three}~
R₂₆Is a hydrogen atom and R₂₇, R₂₈Is X_ThreeWith cyclo
A copolymer having a repeating unit that is a hexylidene group
Contains parentheses and repeats shown in formulas (5), (6) and (7)
Mix and use each polymer of the copolymer consisting of
In addition, a graph having a silicon atom in the side chain as the component (E).
From the initial stage to the end of durability
Especially stable surface lubrication and solvent crack resistance
Can be improved. This is a polyarylate
The structure is represented by R in the formula (1)₁, R_Two, R_Five, R₆Is a methyl group
And R_Three, R_Four, R₇~ R_TenIs a hydrogen atom, and poly
The carbonate structure is represented by R in the formula (2)₁₁~ R₁₄Is hydrogen
An atom, R_Fifteen, R₁₆Is X_TwoWith cyclohexylide
And the siloxane structure is represented by R in the formula (3).₁₇~
R ₂₀Is a methyl group, and R_{twenty one}, R_{twenty two}Is a hydrogen atom,
R in equation (4)_{twenty three}~ R ₂₆Is a hydrogen atom, and R₂₇,
R₂₈Is X_ThreeTogether with a cyclohexylidene group
Closely related, how to enter between each molecular chain, each
How to break the crystallinity, and furthermore, the silicon (E) component inside the film
Molecular groups including graft polymers having a silicon atom in the side chain;
It is presumed that there is a difference in how
This keeps high wear resistance until after durability
High surface lubricity and improved solvent crack resistance
It is presumed that it can be done.

In the present invention, a polyarylate having a repeating unit represented by the formula (1), a polycarbonate having a repeating unit represented by the formula (2), and a polycarbonate having the repeating units represented by the formulas (3) and (4) The viscosity average molecular weight of the copolymer having the repeating unit represented by the formula (1) and the copolymer having the repeating unit represented by the formulas (5), (6) and (7) may be from 10,000 to 200,000. Preferably, it is particularly preferably 15,000 to 120,000. Further, the viscosity average molecular weight (Ma) of the polyarylate as the component (A) is from 30,000 to
105,000, and the viscosity-average molecular weight (Mc) of the polycarbonate as the component (B) is 25,000.
It is particularly preferred that 0 to 55,000 and Ma> Mc.

The mass ratio (Wa) of the polyarylate having the repeating unit represented by the formula (1), the mass ratio (Wc) of the polycarbonate having the repeating unit represented by the formula (2), and the formula (3) And the mass ratio (Ws) of the copolymer having the repeating unit represented by (4) and the mass ratio (Wfs) of the copolymer having the repeating unit represented by the formulas (5), (6) and (7) Is Wa / Wc = 9
5/5 to 5/95, preferably (Ws + Wf
s) / (Wa + Wc) = 1/99 to 30/70. The mass ratio (Wf) of the graft polymer having a silicon atom in the side chain as the component (E) is Wf /
(Wa + Wc + Ws + Wfs) = 0.01 / 100-2
It is preferably 0/100.

The structure of the electrophotographic photosensitive member used in the present invention will be described below. The electrophotographic photoreceptor in the present invention is
The photosensitive layer may be of a single-layer type in which the charge transporting material and the charge generating material are contained in the same layer, or may be of a multilayer type in which the charge transporting layer and the charge generating layer are separated from each other.

In each case, at least the surface layer of the electrophotographic photosensitive member has, as described above, a polyarylate having a repeating unit represented by the formula (1) as the component (A), and a formula (2) as the component (B). ), A copolymer having the repeating units represented by formulas (3) and (4) as the component (C), and formulas (5) and (6) as the component (D). )
And (7) a copolymer having a repeating unit and (E) a graft polymer having a silicon atom in a side chain.

The support to be used is not limited as long as it has conductivity, and examples thereof include metals such as aluminum and stainless steel, and metals having a conductive layer, paper, and plastics. Is mentioned. In particular, when an image input such as LBP is a laser beam, it is preferable to provide a conductive layer for the purpose of preventing interference fringes due to scattering or covering a scratch on the support. This can be formed by dispersing conductive powder such as carbon black and metal particles in a binder resin. The thickness of the conductive layer is preferably 5 to 40 μm, particularly preferably 10 to 30 μm.

An intermediate layer having an adhesive function and a barrier function can be provided thereon if necessary. As the material of the intermediate layer, polyamide, polyvinyl alcohol,
Polyethylene oxide, ethyl cellulose, casein,
Examples include polyurethane and polyether urethane. These are applied by dissolving in an appropriate solvent. The thickness of the intermediate layer is preferably 0.05 to 5 μm, particularly 0.3 to 5 μm.
1 μm is preferred.

In the case of the function separation type, a charge generation layer is formed thereon. Examples of the charge generation material used in the present invention include selenium-tellurium, pyrylium, thiapyrylium dyes, phthalocyanine, anthantrone, dibenzpyrenequinone, trisazo, cyanine, disazo, monoazo, indigo, quinacridone, and asymmetric quinocyanine pigments. No. The charge generation layer comprises a homogenizer, an ultrasonic dispersion, a ball mill, a vibration ball mill, a sand mill, an attritor, a roll mill, a liquid collision type high-speed disperser, and the like, together with a binder resin and a solvent in an amount of 0.3 to 4 times the mass of the charge generation material. And well-dispersed, and the dispersion is applied and dried. The thickness of the charge generation layer is preferably 5 μm or less, and particularly preferably 0.1 to 2 μm.

The charge transport layer is formed by applying and drying a coating material in which a charge transport material and a binder resin are dissolved in a solvent. Examples of the charge transport material used include a triarylamine compound, a hydrazone compound, a stilbene compound, a pyrazoline compound, an oxazole compound, a triallylmethane compound, and a thiazole compound.

These are combined with 0.5 to 2 times the amount of the binder resin, applied and dried to form a charge transport layer. The thickness of the charge transport debris is preferably 5 to 40 μm, and particularly preferably 15 to 30 μm.

When the photosensitive layer is of a single-layer type, the photosensitive layer is formed by dispersing and dissolving the above-described charge generating material and charge transporting material in the above-described binder resin, followed by drying. The film thickness is preferably 5 to 40 μm, particularly preferably 1 to 40 μm.
5 to 30 μm is preferred.

FIG. 1 shows a schematic configuration of an electrophotographic apparatus having the electrophotographic photosensitive member of the present invention.

In the drawing, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate around a shaft 2 in a direction of an arrow at a predetermined peripheral speed. The photoreceptor 1 rotates during the rotation process.
The primary charging means 3 receives a uniform charge of a predetermined positive or negative potential on its peripheral surface, and then exposes light 4 from exposure means (not shown) such as slit exposure or laser beam scanning exposure.
Receive. Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 1.

The formed electrostatic latent image is then
The toner-developed image developed by the toner image is transferred from a paper supply unit (not shown) between the photoconductor 1 and the transfer unit 6 in synchronization with the rotation of the photoconductor 1 and fed to a transfer material 7 fed therefrom. The image is sequentially transferred by the transfer unit 6.

The transfer material 7 which has undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 8 and subjected to image fixing, thereby being printed out of the apparatus as a copy.

The surface of the photoreceptor 1 after the transfer of the image is cleaned by a cleaning blade 9 to remove the untransferred toner, and further subjected to a charge elimination process by pre-exposure light 10 from a pre-exposure unit (not shown). Later, it is used repeatedly for image formation. When the primary charging means 3 is a contact charging means using a charging roller or the like as shown in the figure, the pre-exposure is not necessarily required.

In the present invention, a plurality of components such as the above-described electrophotographic photosensitive member 1, primary charging means 3, developing means 5 and cleaning means 9 are integrally connected as a process cartridge. The process cartridge may be configured to be detachable from a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer.
For example, at least one of the primary charging unit 3, the developing unit 5 and the cleaning unit 9 is integrally supported together with the photoreceptor 1 to form a cartridge, which can be attached to and detached from the apparatus main body using a guide unit such as a rail 12 of the apparatus main body. Process cartridge 11.

When the electrophotographic apparatus is a copier or a printer, the exposure light 4 is reflected or transmitted from the original, or the original is read by a sensor and converted into a signal. Laser beam scanning, L
Light emitted by driving the ED array, driving the liquid crystal shutter array, and the like.

The electrophotographic photosensitive member of the present invention can be used not only for an electrophotographic copying machine but also for a laser beam printer,
RT printer, LED printer, LCD printer,
It can be widely used in electrophotographic applications such as laser plate making.

Hereinafter, description will be made in accordance with embodiments.

The polyarylate having a repeating unit represented by the formula (1) and the polycarbonate having a repeating unit represented by the formula (2) used in the present invention, and the repeating units represented by the formulas (3) and (4) Copolymer having units, and formulas (5), (6) and (7)
The copolymer having a repeating unit represented by was synthesized by a conventional method. Further, the viscosity average molecular weight was determined by a conventional method.

Table 9 shows the graft polymers (compound Nos. 9-1 to 9-4) having a polymerizable monomer having a silicon atom in the side chain as a constituent component used in the following Examples. .

[0092]

[Table 19]

[0093]

[Example 1] An Al cylinder having a diameter of 30 mm and a diameter of 357.5 mm was used as a support, and a coating composed of the following materials was applied to the support by a dipping method.
For 30 minutes to form a conductive layer having a thickness of 15 μm.

Conductive pigment: 10 parts of barium sulfate treated with SnO ₂ coating Pigment for resistance control: 2 parts of titanium oxide Binder resin: 6 parts of phenolic resin Leveling material: 0.001 part of silicone oil Solvent: methanol, methoxypropanol 0.2 / 0.
8 20 parts Next, on this conductive layer, 3 parts of N-methoxymethylated nylon and 3 parts of copolymerized nylon were mixed with 65 parts of methanol,
A solution dissolved in a mixed solvent of 30 parts of n-butanol was applied by a dipping method to form an intermediate layer having a thickness of 0.5 μm.

Next, in the X-ray diffraction of CuKα, the folding angles 2θ ± 0.2 ° are 9.0 °, 14.2 °, 23.9 °.
4 parts of oxytitanium phthalocyanine having strong peaks at 0 ° and 27.1 ° and polyvinyl butyral (trade name:
Esrec BM2, 2 parts of Sekisui Chemical Co., Ltd.) and 60 parts of cyclohexanone were dispersed in a sand mill using φ1 mm glass beads for 4 hours.
The resulting mixture was added to prepare a charge generation layer dispersion. This was applied by an immersion method to form a charge generation layer having a thickness of 0.3 μm.

Next, in order to form a charge transport layer, a paint for the charge transport layer was prepared. Bisphenol C type (repeat unit example (1-2)) polyarylate (viscosity average molecular weight 61,000) 50 parts, bisphenol Z type (repeat unit example (2-13)) polycarbonate (viscosity average molecular weight 61,000) 40 copies, repetitive stand alone example (3
-6) and a repeating unit represented by the repeating unit example (4-13),

[0097]

[Outside 17]

Copolymer (viscosity average molecular weight 42,000) 5 wherein (2-13) is 98% by mass of the total mass of the copolymer
Part, repeating unit examples (5-1), (6-1) and (7)
-1) a repeating unit represented by

[0099]

[Outside 18]

A copolymer having a repeating unit example (5-1) of 45% by mass of the total mass of the copolymer and a repeating unit example (6-1) of 45% by mass (viscosity average molecular weight of 42,000%) was used.
0) 5 parts of a graft polymer having a polymerizable monomer having a silicon atom in a side chain as a component (Compound No. 9-
1) 2 parts, 90 parts of an amine compound having the following structural formula, and

[0101]

[Outside 19]

10 parts of an amine compound having the following structural formula

[0103]

[Outside 20]

Was dissolved in 700 parts of monochlorobenzene and 300 parts of dimethoxymethane to obtain a paint for a charge transport layer. This paint was applied by a dipping method, and was dried at 120 ° C. for 2 hours to form a 25 μm charge transport layer.

Next, the evaluation will be described.

The apparatus was manufactured by Canon's LBP “ImageCl
ass 4000 ”(process speed 144.5mm /
s) was modified and used. For the remodeling, pre-exposure with a fuse lamp was attached immediately before the charger, and the lamp was used only when the residual potential was measured. The potential measurement was performed by setting the dark part to Vd, the laser light irradiation part to Vl, and the pre-exposure irradiation part to Vr.

The prepared electrophotographic photoreceptor was separated into 23
The paper passing durability was given at 55 ° C. and 55% RH. The sequence is an intermittent mode in which one print is stopped for each print,
When 00 sheets (A4 paper, printing rate 5%) were printed, the potential was measured, and then the sheet was passed through up to 10,000 sheets to measure the shaving amount of the photoconductor.

In a high-temperature, high-humidity environment of 32.5 ° C. and 85% RH, 50,000 sheets (A4 paper, print ratio 0.9%) were passed. The sequence is an intermittent mode in which the printing is stopped once for every two prints, the printing is paused for 10 minutes for every 500 prints, and the cartridge is repeatedly taken in and out every 1,000 prints. The turning was evaluated. It should be noted that the toner was replenished as needed during a print pause of 10 minutes. Further, the solvent cracking property allows finger grease to adhere to the surface,
After standing for a time, the presence or absence of solvent cracks was observed under a microscope. To evaluate the pot life, each charge transport layer paint was allowed to stand in a closed container at room temperature (23 ° C.) for one week, and then the dissolved state was observed.

Example 2 A polyarylate obtained by copolymerizing bisphenol Z type (repeat unit example (1-23)) and bisphenol C type (repeat unit example (1-2)) at a mass ratio of 1/1 as a polymer to be used. (Viscosity average molecular weight = 45,000), and carried out in the same manner as in Example 1 except that the conditions shown in Table 10 were used. The results are shown in Table 11.

[Examples 3 to 17] The polymer to be used, the viscosity average molecular weight, the graft polymer having a polymerizable monomer having a silicon atom in the side chain as a constituent component, and the mixing ratio were 10%.
The procedure was performed in the same manner as in Example 1 except that the conditions shown in the table were used. The results are shown in Table 11.

[Embodiment 18] A modified machine (process speed 235.5 mm / s) of Canon LBP "ImageClass4000" was used as an evaluation apparatus. Modification is performed by changing the high voltage setting, turning the drive motor quickly, increasing the primary AC frequency, changing the laser from single beam to double beam, changing the laser light amount, changing the scanner rotation speed, and reviewing the paper feed sequence. Was. Performed in the same manner as in Example 1 except that the polymer to be used, the viscosity average molecular weight, the graft polymer having a polymerizable monomer having a silicon atom in the side chain as a component, and the mixing ratio were set to the conditions shown in Table 10. Was. The results are shown in Table 11.

[Comparative Examples 1 to 8] The polymer to be used, the viscosity average molecular weight, the graft polymer having a polymerizable monomer having a silicon atom in the side chain as a constituent, and the mixing ratio were 10th.
The procedure was performed in the same manner as in Example 1 except that the conditions shown in the table were used. The results are shown in Table 11.

[0113]

[Table 20]

[0114]

[Table 21]

The potential evaluation results were all good in dark area potential, light area potential, residual potential, and potential after printing 3,000 sheets. There were no cracks generated, gelled, or not dissolved, and the solvent cracking property and pot life were all good.

In Examples 1 to 18, good results were obtained for all evaluation items. However, in Comparative Example 7, an image defect occurred when the durability was 50,000 sheets or less. The cause was abrasion of the photoreceptor. Comparative Examples 1, 2, 3, 4, 5, 6, 8
In each case, the cleaning blade was not turned up under high temperature and high humidity, and good results were obtained without occurrence of image defects up to 50,000 sheets of durability. However, when the rotation of the photosensitive member was started or stopped, the result was slight. However, generation of abnormal noise due to friction between the photoreceptor and the blade was observed.

As described above, by containing the polyarylate, the polycarbonate, the modified polycarbonate, the fluorinated modified polycarbonate, and the graft polymer having a polymerizable monomer having a silicon atom in a side chain as a constituent component, the present invention can be used. And an electrophotographic photoreceptor having both excellent mechanical strength and surface lubricity until endurance. Further, it is possible to provide an electrophotographic photoreceptor that has good electrophotographic properties, good coatability at the time of production and a good paint pot life, and does not generate curling or abnormal noise even with a general cleaning blade. it can.

[0118]

As described above, the electrophotographic photoreceptor of the present invention has both excellent mechanical strength and surface lubricity until after the endurance, and has good electrophotographic properties. In addition, the improvement in solubility and pot life has expanded the range of choice of materials (repeating units), making it possible to provide an electrophotographic photosensitive member according to the purpose of use.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus having an electrophotographic photosensitive member of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrophotographic photoreceptor of the present invention 2 axis 3 Primary charging means 4 Exposure light 5 Developing means 6 Transfer means 7 Transfer material 8 Image fixing means 9 Cleaning blade 10 Pre-exposure light 11 Process cartridge 12 Rail

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C08L 69/00 C08L 69/00 // C08F 290/06 C08F 290/06 299/08 299/08 F-term (reference) 2H068 AA13 BB07 BB26 BB27 BB32.

Claims (13)

[Claims] 1. An electrophotographic photoreceptor having a support and a photosensitive layer, wherein the surface layer of the electrophotographic photoreceptor is represented by the following components (A) to (E) and (A) the following formula (1). A polyarylate having a repeating unit, (B) a polycarbonate having a repeating unit represented by the following formula (2), (C) a copolymer having a repeating unit represented by the following formulas (3) and (4), and (D) Equations (5) and (6) below
And (E) a graft polymer having, as a component, a polymerizable monomer having a silicon atom in a side chain. Photoconductor. [Outside 1] (X ₁ is a carbon atom or a single bond (in this case, R ₅ , R ₆
), R _{1 to} R ₄ represent a hydrogen atom, a halogen atom, an optionally substituted alkyl group, or an optionally substituted aryl group, and R ₅ and R ₆ represent a hydrogen atom, a halogen atom, A good alkyl group, an optionally substituted aryl group, or an optionally substituted alkylidene group formed by combining R ₅ and R ₆ , wherein R _{7 to} R ₁₀ are a hydrogen atom, a halogen atom, Represents an optionally substituted alkyl group and an optionally substituted aryl group). [Outside 2] [Outside 3] [Outside 4] [Outside 5] [Outside 6] [Outside 7] 2. The electrophotographic photoreceptor according to claim ₁ , wherein said R ₁ , R ₂ , R ₅ , and R ₆ are methyl groups, and said R ₃ , R ₄ , R _{7 to} R ₁₀ are hydrogen atoms. . 3. The electrophotographic photoreceptor according to claim 1, wherein R _{11 to} R ₁₄ are a hydrogen atom, and R ₁₅ and R ₄ are a cyclohexylidene group together with the X ₂ . 4. The electrophotographic photoreceptor according to claim 1, wherein R ₁₇ and R ₁₈ are an alkylene group having 2 to 3 carbon atoms, and R _{19 to} R ₂₂ are a methyl group. 5. The R_{twenty three}~ R₂₆Is a hydrogen atom;
R₂₇, R₂₈Is the X _ThreeTogether with the cyclohexylidene group
The electrophotographic photoreceptor according to claim 1. 6. The electrophotographic photosensitive member according to claim 1, wherein R _{29 to} R ₃₂ are a hydrogen atom. 7. The R₃₃, R₃₄Is a hydrogen atom or methyl
And the above R ₃₅, R₃₆Is a hydrogen atom.
7. The electrophotographic photosensitive member according to any one of items 1 to 6. 8. The electrophotographic photosensitive member according to claim 1, wherein R ₃₇ and R ₃₈ are an alkylene group having 2 to 3 carbon atoms, and R _{39 to} R ₄₂ are a methyl group. 9. The graft polymer having a polymerizable monomer having a silicon atom in a side chain as the component (E) as a component has a silicon atom in a side chain and a polymerizable functional group at a terminal. 9. A monomer obtained by copolymerizing a monomer and a macromonomer comprising a polymerizable monomer having no silicon atom or an oligomer having a polymerizable functional group at a terminal. 2. The electrophotographic photoreceptor of claim 1. 10. The mass ratio (Wa) of the polyarylate as the component (A), the mass ratio (Wc) of the polycarbonate as the component (B), and the mass ratio of the copolymer as the component (C) ( Ws), the mass ratio (Wfs) of the copolymer as the component (D) and the mass ratio (Wf) of the graft polymer containing a silicon atom in the side chain as the component (E) satisfy the following relationships. The electrophotographic photoreceptor according to any one of claims 1 to 9, wherein Wa / Wc = 95 / 5-5 / 95 (Ws + Wfs) / (Wa + Wc) = 1 / 99-30 /
70 Wf / (Wa + Wc + Ws + Wfs) = 0.02 / 10
0-20 / 100 11. The polyarylate has a viscosity average molecular weight (Ma) of 30,000 to 105,000, and the polycarbonate has a viscosity average molecular weight (Mc) of 25,000 to 11.
2. The method according to claim 1, wherein 55,000 and Ma> Mc.
An electrophotographic photoreceptor according to any one of claims 10 to 10. 12. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1 and at least one unit selected from the group consisting of a charging unit, a developing unit and a cleaning unit. A process cartridge which is detachable from an apparatus main body. 13. An electrophotographic apparatus comprising: the electrophotographic photosensitive member according to claim 1; a charging unit; an exposing unit; a developing unit; and a transfer unit.