JP3186010B2 - Electrophotographic photoreceptor, electrophotographic apparatus and apparatus unit - Google Patents

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 having excellent durability and an electrophotographic apparatus having the same.

[0002]

2. Description of the Related Art An electrophotographic photosensitive member needs to have sensitivity, electric characteristics and optical characteristics according to an applied electrophotographic process. Since electric and mechanical external forces are directly applied by processes such as charging, toner development, transfer to paper, and cleaning, they are required to have durability. Specifically, it is required to have durability against abrasion of the surface due to friction, generation of scratches, and deterioration of the surface under high humidity. In addition, there is a problem that toner adheres to the surface layer due to repetition of development and cleaning with toner. To solve this problem, improvement in the cleaning property of the surface layer is required. Various methods have been studied to satisfy the characteristics required for the surface layer as described above. Among them, means for providing a resin layer in which fluorine-based resin particles are dispersed on the surface is effective. The friction coefficient of the surface layer is reduced by the dispersion of the fluororesin particles, so that the cleaning property is improved, and the durability against abrasion and scratches is improved. However, fluorine resin particles have problems in dispersibility and cohesion, it is difficult to form a uniform and smooth film, and the resulting surface layer is free from image defects such as image unevenness and pinholes. I couldn't. In most cases, the use of binder resins, dispersing aids, and the like having good dispersibility caused deterioration of electrophotographic characteristics, and no effective one was found. An example of the dispersing aid is a fluorine-based comb-type graft polymer resin. In this case, the dispersion of the fluorine-based resin particles is good, but there is a problem that the image quality is deteriorated by repeated use under high humidity. That is, the residual potential increased due to repeated use, and image fogging occurred.
The decrease in the residual potential can be reduced to some extent by reducing the amount of the fluorine-based resin particles contained in the surface layer and / or the fluorine-based comb-type graft polymer resin, but it is necessary if the fluorine-based resin particles are small. Abrasion resistance was not obtained, and if the addition amount of the fluorine-based comb-type graft polymer resin was small, the dispersibility of the fluorine-based resin particles was reduced, and a satisfactory surface layer film could not be obtained, which was a problem.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the coefficient of friction of a surface layer, to have cleaning properties, durability against abrasion and scratches, and not to increase the residual potential in repeated electrophotographic processes. Another object of the present invention is to provide an electrophotographic photoreceptor capable of always obtaining a high-quality image and an electrophotographic apparatus having the same.

[0004]

That is, the present invention relates to an electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the surface layer contains fluorine-based resin particles and fluorine-based comb-type graft polymer resin. The quaternary ammonium salt content in the surface layer is 100 ppm based on the total weight of solids in the surface layer.
An electrophotographic photosensitive member characterized by the following, and an electrophotographic apparatus having the same.

[0005] As a result of the examination, the surface layer was made of fluororesin particles,
Increase in residual potential due to repeated use in an electrophotographic photoreceptor containing a fluorine-based comb polymer and a fluorine-based comb polymer is due to the formation of trap sites by the action of quaternary ammonium salts and impurities contained in the surface layer as impurities. Was found to be the main cause. The fourth contained in the surface layer
When the amount of the quaternary ammonium salt was set to 100 ppm or less, it was found that there was little increase in the residual potential due to repeated use and there was no practical problem.

[0006] Examples of routes through which the quaternary ammonium salt is introduced into the surface layer include those introduced as impurities of fluorine-based resin particles and fluorine-based comb-type graft polymerization resins. In particular, a quaternary ammonium salt is always used in the process of producing a fluorine-based comb-type graft polymer resin.

In general, the structure of a quaternary ammonium salt is one in which four hydrogen atoms of the ammonium salt are replaced with a hydrocarbon substituent, and is represented by the following general formula 1.

[0008]

Embedded image[Wherein, R₁ , R_Two , R_Three , R_Four Are independently carbonized
A hydrogen substituent, and the hydrocarbon substituent is an alkyl group
(E.g., methyl, ethyl, propyl, n-butyl
Group, iso-butyl group, aluminum group, etc.), cycloalkyl
Group, aryl group (for example, phenyl group, tolyl group,
Groups such as a silyl group and a naphthyl group). So
There is also an example in which each substituent further contains a substituent. X
As a hydroxyl group or an acid group (for example, NO_Three ^-, SO_Four ^2- , CH
_Three COO^- Etc.), halogen atoms (fluorine, chlorine, odor
, Iodine). ] As the name and structural formula of a typical quaternary ammonium salt
Examples include the following. Tetra-n-amylammonium Bro
middle [CH_Three (CH_Two )_Four ]_Four NBr Tetra-n-amylammonium Chl
oride [CH_Three(CH_Two )_Four ]_Four NCl Tetra-n-amylammonium Iod
ido [CH_Three (CH_Two )_Four ]_Four NI Tetra-n-butylammonium Br
imide [CH_Three(CH_Two )_Three ]_Four NBr Tetra-n-butylammonium Ch
loride [CH _Three (CH_Two )_Three ]_Four NCl Tetra-n-butylammonium Io
dodo [CH_Three (CH_Two )_Three ]_Four NI Tetra-n-butylammonium Fl
uoride [CH _Three (CH_Two )_Three ]_Four NF Tetra-n-butylammonium Hy
droxide [CH_Three (CH_Two )_Three ]_Four NOH Tetra ethylammonium Bro
middle [CH_Three (CH_Two )]_Four NBr Tetra ethylammonium Chl
oride [CH_Three(CH_Two )]_Four NCl Tetra ethylammonium Iod
ido [CH_Three (CH_Two )]_Four NI Tetra ethylammonium Flu
oride [CH_Three(CH_Two )]_Four NF Tetra ethylammonium Hyd
rodide [CH _Three (CH_Two )]_Four NOH Tetra methylammonium Br
imide (CH_Three)_Four NBr Tetra methylammonium Ch
loride (CH _Three )_Four NCl Tetra methylammonium Io
dodo (CH_Three ) _Four NI Tetra methylammonium Fl
uoride (CH _Three )]_Four NF Tetra methylammonium Hy
droxide (CH_Three )]_Four NOH Reduce the amount of quaternary ammonium salt contained in the surface layer
Examples of the method of causing the fluorinated resin particles and / or
Quaternary a contained in nitrogen-based comb type graft polymer resin
Method to reduce the amount of ammonium salt by purification means, synthesis
Reduce the amount of quaternary ammonium salt added in the stage
There is a method to make it.

Examples of the method for purifying the fluorine-based comb type graft polymer resin used in the present invention include simple extraction and reprecipitation purification. A more preferable method is to use a fluorine-based comb type graft polymer resin with a good solvent. Dissolving the solution with high pressure and passing it through a narrow nozzle for reprecipitation purification, heating the fluorine-based comb type graft polymer resin to break the crystals, dissolving with a good solvent and reprecipitation purification, supercritical fluid And a method of purification using

For example, as a good solvent used for reprecipitating and refining the fluorine-based comb type graft polymer resin, it is more effective to select a solvent having particularly good solubility in the fluorine-based comb type graft polymer resin. Particularly preferred examples include ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone and cyclohexanone; ethers such as diethyl ether and tetrahydrofuran; esters such as ethyl acetate and butyl acetate; hydrocarbons such as toluene and benzene; chlorobenzene And the like, and halogenated hydrocarbons.

As the poor solvent used for purifying the fluorine-based comb type graft resin of the present invention, those having low solubility in the fluorine-based comb type graft polymer resin are suitable. Particularly preferred examples are methanol, ethanol and Alcohols such as butanol and isopropyl alcohol; hydrocarbons such as normal hexane, petroleum ether, and cyclohexane; and water.

With respect to the method of reprecipitation purification, a solution of a fluorine-based comb type graft polymer resin dissolved in a good solvent is mixed with a poor solvent.

The fluorine-based comb-type graft polymer resin used in the present invention is composed of a macromonomer composed of a relatively low molecular weight oligomer having a polymerizable functional group at one end of each molecular chain and having a molecular weight of about 1,000 to 10,000, and a fluorine-based polymer. It is obtained by copolymerizing a reactive monomer, and has a structure in which a macromonomer polymer hangs in a plate shape on the trunk of a fluoropolymer. As the macromonomer, those having an affinity for the resin to which the graft polymerization resin is added are selected. For example, polymers or copolymers of acrylates, methacrylates, styrene compounds and the like are used.

On the other hand, as the fluorine-based polymerizable monomer,
One or more polymerizable monomers having a fluorine atom in a side chain as shown in the following (2) to (7) can be used, but the invention is not limited thereto.

[0015]

Embedded image In the formula, R ₅ represents a hydrogen atom or a methyl group. R ₆ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or a nitrile group, and may be a combination of several kinds thereof. n is an integer of 1 or more, m is an integer of 1 to 5, k is 1 to
Represents an integer of 4, and m + k = 5.

The content of the fluorine-based monomer residue in the fluorine-based comb type graft polymer resin is preferably 5 to 90% by weight in the fluorine-based comb type graft polymer resin, and 10 to 70% by weight.
% By weight is more preferred. If the content of the fluorine-based monomer residue is less than 5% by weight, the effect of improving the hydrophobicity cannot be sufficiently exerted, and if the content of the fluorine-based monomer residue exceeds 90% by weight, the solubility with the macromonomer is reduced. become worse.

The fluorine-based comb-type graft polymerization resin used in the present invention is preferably a resin graft-polymerized from a macromonomer selected from acrylates, methacrylates, and styrene compounds, and a perfluoroalkylethyl methacrylate. Particularly, a resin obtained by graft polymerization of perfluoroalkylethyl methacrylate based on methyl methacrylate is preferable.

The fluororesin particles used in the present invention include tetrafluoroethylene resin, trifluoroethylene chloride resin, hexafluoroethylene propylene resin, vinyl fluoride resin, vinylidene fluoride resin and difluoride dichloride. It is desirable to appropriately select one or more of ethylene resins and copolymers thereof, and particularly preferable are tetrafluoroethylene resins and vinylidene fluoride resins. The molecular weight of the resin and the particle size of the particles can be appropriately selected and are not particularly limited.

The presence of the fluorine-based graft polymer resin improves the dispersibility of the fluorine-based resin particles and prevents aggregation during the formation of a coating film, so that a very uniform and smooth fluorine-based resin particle dispersion layer is formed. You. In addition, since the fluorine-based graft polymer resin has the above-described structure, it has excellent compatibility with a coating solution containing a binder resin for forming a resin layer, and therefore does not migrate or exude onto the surface layer.

The content of the dispersed fluororesin particles is as follows:
Based on the solid content weight of the surface layer, 1 to 50% is appropriate, and particularly preferably 5 to 30%. If the content is less than 1%, the modifying effect by dispersion of the fluororesin particles is not sufficient,
On the other hand, if it exceeds 50%, the light transmittance is reduced, and the mobility of carriers is also reduced. The content of the fluorine-based graft polymer resin is 0.01 to 10% based on the weight of the solid content.
Is suitable, and particularly preferably 0.02 to 2%. When the content is less than 0.01%, the effect of improving the dispersibility of the fluororesin particle group is not sufficient. On the other hand, when the content is more than 10%, the fluorograft resin is present not only on the coating film surface but also in the bulk. Therefore, due to the compatibility problem with the resin, the accumulation of residual charges when the electrophotographic process is repeatedly performed occurs.

The binder resin for forming the resin layer is as follows:
Any polymer may be used as long as it has a film-forming property, but polymethacrylate, polycarbonate, polyacrylate, polyester, polysulfone, and the like are preferable in terms of having a certain degree of hardness by themselves and not hindering carrier transport. .

As a method for purifying the fluororesin particles, there is a method for extracting or heating to decompose a quaternary ammonium salt.

As a method for preparing a coating solution for forming the surface layer of the electrophotographic photoreceptor of the present invention, a binder resin, a charge transporting material and the like are simultaneously mixed with a solvent together with fluorine resin particles and a fluorine comb type graft polymer resin. It may be dispersed. Alternatively, a dispersion may be prepared by previously dispersing the fluorine-based resin particles, the fluorine-based comb-type graft polymer resin, and the binder resin, and may be mixed with a separately dispersed coating solution. In preparing the coating solution for the electrophotographic photoreceptor or the fluororesin particle dispersion used in the present invention, simple stirring and mixing may be used, but if necessary, a dispersing means such as a ball mill, a roll mill, a sand mill, and a high-pressure homogenizer is used.

A coating solution for an electrophotographic photosensitive member used in the present invention,
Alternatively, a solvent having good solubility in a binder resin and a charge transport material, good dispersibility in a pigment, and good coatability are selected as a solvent used for preparing a fluororesin particle dispersion.

Examples of the material of the conductive support used in the present invention include metals such as aluminum, copper, nickel and silver or alloys thereof; conductive metal oxides such as antimony oxide, indium oxide and tin oxide; Examples thereof include carbon fiber, carbon black, and a mixture of graphite powder and resin.

Further, it is possible to provide a conductive layer on the support for covering defects on the support and protecting the support. For example, metal powders such as aluminum, copper, nickel, and silver; conductive metal oxides such as antimony oxide, indium oxide, and tin oxide; polymer conductive materials such as polypyrrole, polyaniline, and polymer electrolyte; carbon fibers, and carbon black , Graphite powder; or a conductive substance such as a conductive powder whose surface is coated with these conductive substances,
Thermoplastic resins such as acrylic resin, polyester resin, polyamide resin, polyvinyl acetate resin, polycarbonate resin and polyvinyl butyral resin; thermosetting resins such as polyurethane resin, phenol resin and epoxy resin;
Examples thereof include those dispersed in a binder resin such as a photocurable resin, and those obtained by further adding a necessary additive to a support.

The photosensitive layer may have a single-layer structure or a laminated structure in which functions are separated into a charge generation layer and a charge transport layer.

Examples of the material for the charge generation layer of the laminated photoreceptor include azo pigments such as Sudan red and chlordian blue; phthalocyanine pigments such as copper phthalocyanine and titanyl phthalocyanine; quinone pigments such as anthranthrone; perylene pigments and indigo pigments Charge generation materials such as acrylic resin, polyester resin, polyamide resin, polyvinyl acetate resin, polycarbonate resin,
Thermoplastic resins such as polyvinyl butyral resin and polyvinyl benzal resin; those dispersed in binder resins such as thermosetting resins such as polyurethane resins, phenolic resins and epoxy resins; and those dispersed and applied in an appropriate solvent. Can be Furthermore, it is also possible to add additives as needed.

Examples of the material for the charge transport layer include charge transport materials such as hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, thiazole compounds and triarylamine compounds, and acrylic resins, polyester resins, and the like. Polyarylate resin,
Thermoplastic resins such as polyvinyl chloride resin, polycarbonate resin, polyvinyl butyral resin, and polymethacrylate resin; binder resins such as polyurethane resin, phenol resin, and epoxy resin; methanol, ethanol, butanol, isopropyl alcohol, etc. Alcohols; ketones such as methyl ethyl ketone, acetone, methyl isopropbutyl ketone, and cyclohexanone; ethers such as diethyl ether and tetrahydrofuran; esters such as ethyl acetate and propyl acetate; hydrocarbons such as normal hexane, petroleum ether, and toluene. Those dispersed in other suitable solvents, such as halogenated hydrocarbons such as monochlorobenzene and dichloromethane, and those further coated with additives as required. It is. In addition, a conductive polymer can also be used.

As a coating method used in the present invention, a dip coating method, a spray coating method, a roll coater coating method, a gravure coater coating method, or the like can be applied.

In the present invention, the layer containing the fluororesin particles and, for example, the fluorine-containing comb type graft polymer resin purified by reprecipitation after heat treatment may be used as a surface layer of a photoreceptor (directly used for a toner, a developing device, a cleaning device, etc.). It is effective to apply it to the contacting layer. Examples of the layer configuration of the photoreceptor include a photosensitive layer in a single-layer structure, a charge transport layer in a layered photoreceptor in which a charge transport layer is provided on a charge generation layer, and a charge generation layer on a charge transport layer. It can be used as a conductive layer in a laminated photoreceptor of the type in which a layer is provided and a conductive layer is further provided thereon, and as a protective layer in a photoreceptor in which a protective layer is provided on the photosensitive layer.

The electrophotographic photosensitive member of the present invention can be applied to a photosensitive drum generally used in an electrophotographic apparatus such as a copying machine, a laser printer, an LED printer, and a liquid crystal shutter printer.

Further, the present invention comprises an electrophotographic apparatus having the electrophotographic photoreceptor of the present invention.

FIG. 1 shows a schematic configuration of a general transfer type electrophotographic apparatus using the drum type photosensitive member of the present invention. In the figure, reference numeral 1 denotes a drum type photosensitive member as an image carrier, and a shaft 1
It is rotationally driven at a predetermined peripheral speed in the direction of the arrow around a.
The photoreceptor 1 is uniformly charged with a predetermined positive or negative potential on its peripheral surface by a charging means 2 during the rotation process, and then, in an exposure section 3, a light image exposure L (slit exposure / Laser beam scanning exposure). As a result, an electrostatic latent image corresponding to the exposure image is sequentially formed on the peripheral surface of the photoconductor. The electrostatic latent image is then developed with toner by a developing unit 4, and the developed toner image is transferred by a transfer unit 5 between a photosensitive unit 1 and a transfer unit 5 from a paper supply unit (not shown) in synchronization with the rotation of the photosensitive unit 1. It is sequentially transferred to the surface of the transfer material 9 taken and fed. The transfer material 9 having undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 8 and subjected to image fixing, and is printed out of the apparatus as a copy. The surface of the photoreceptor 1 after the image transfer is cleaned and cleaned by removing the untransferred toner by the cleaning unit 6, subjected to a charge removal process by the pre-exposure unit 7, and used repeatedly for image formation. As the uniform charging means 2 for the photoreceptor 1, a corona charging device or the like is used. The transfer device 5 also uses corona transfer means or the like. As an electrophotographic apparatus, a plurality of components such as the above-described photoreceptor, developing means, and cleaning means are integrally connected as an apparatus unit, and this unit is configured to be detachable from the apparatus body. You may. For example, the photoreceptor 1 and the cleaning means 6 may be integrated into one apparatus unit, and may be configured to be detachable using a guide means such as a rail of the apparatus body. At this time, the above-described device unit may be provided with a charging unit and / or a developing unit. When the electrophotographic apparatus is used as a copying machine or a printer, the light image exposure L uses light reflected from or transmitted from a document. Alternatively, the scanning is performed by scanning a laser beam, driving a light emitting diode array, or driving a liquid crystal shutter array based on the read signal of a document according to the signal.

[0035]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to specific examples, but the present invention is not limited to the following examples. Example 1 2000 parts by weight of conductive titanium oxide coated with tin oxide containing 10% antimony oxide as a conductive layer coating step;
2500 parts by weight of phenolic resin, methyl cellosolve 20
00 parts by weight and 500 parts by weight of methanol were dispersed in a sand mill using φ1 mm glass beads for 2 hours to prepare a coating solution for a conductive layer.

Aluminum cylinder (φ30mm × 36
0 mm, thickness 1 mm)
It was dried at 160 ° C. for 25 minutes by a drying apparatus. The thickness of the conductive layer was 20 μm.

Next, the reprecipitated N
5. 1000 parts by weight of methoxymethylated nylon 6 and
250 parts by weight of 12.66.610 copolymerized nylon was dissolved in a mixed solvent of 5000 parts by weight of methanol and 5000 parts by weight of butanol to prepare a coating solution for an intermediate layer. The above coating material was further applied by dip coating on the above-described aluminum cylinder on which the conductive layer had been applied, and dried at 95 ° C. for 7 minutes by a drier. The thickness of the intermediate layer was 0.70 μm.

Next, 400 parts by weight of a disazo pigment having the following structural formula was applied as a coating step of the charge generation layer.

[0039]

Embedded image 200 parts by weight of a polyvinyl butyral resin (butyralization ratio: 68%, weight average molecular weight: 24000) and 5,000 parts by weight of cyclohexanone were dispersed in a sand mill using φ1 mm glass beads for 24 hours, and 5,000 parts by weight of tetrahydrofuran was further added to coat the charge generating layer. A liquid was prepared. This solution was further centrifuged (7000 rpm, 30
Minutes) to remove bead residue and dust. The above-mentioned coating material for a charge generation layer was applied by dip coating on the cylinder on which the intermediate layer had been applied, and dried at 85 ° C. for 7 minutes. The thickness of the charge generation layer is 0.1
It was 5 μm.

Next, as a step of purifying the fluorine-based comb type graft polymer resin, a fluorine-based comb type graft polymer resin (trade name: GF-300, manufactured by Toa Gosei Chemical Industry Co., Ltd.) 800
A part by weight (solid content: 25%) was dropped and stirred into 9000 parts by weight of methanol at a dropping rate of 100 cm ³ / min.
The resulting precipitate was separated and recovered from methanol by suction filtration, and then dried at 50 ° C. for 24 hours using a vacuum drier. Further, this fluorine-based comb-type graft polymer resin was dissolved in tetrahydrofuran to obtain a solid content of 25%, and the solution was made 100 cm.
^The mixture was dropped and stirred in 9000 parts by weight of methanol at a dropping rate of ³ / min, and reprecipitated and purified again. The resulting precipitate was separated and recovered from methanol by suction filtration, and then dried at 50 ° C. for 24 hours using a vacuum dryer to obtain a purified fluorine-based comb-type graft polymer resin. Further, this fluorine-based comb-type graft polymer resin is dissolved again in tetrahydrofuran to make the solid content 25%, and this solution is added at a dropping rate of 100 cm ³ / min to 900.
The mixture was dropped and stirred in 0 parts by weight of methanol to perform a third reprecipitation purification. The resulting precipitate was separated and recovered from methanol by suction filtration, and then dried at 50 ° C. for 24 hours using a vacuum dryer to obtain a purified fluorine-based comb-type graft polymer resin.

Next, as a purification step of the tetrafluoroethylene resin particles, tetrafluoroethylene resin particles (trade name: Lubron L)
-2, manufactured by Daikin Industries, Ltd.)
Add 500 parts by weight of tetrahydrofuran and stir for 30 minutes. Only the tetrafluoroethylene resin particles were separated and collected by a centrifugal separator. After repeating this process three times, the product was dried at 50 ° C. for 24 hours using a vacuum drier to obtain purified tetrafluoroethylene resin particles.

Next, as a process for preparing a dispersion of tetrafluoroethylene resin particles, 100 parts by weight of tetrafluoroethylene resin particles purified by the above process and 100 parts by weight of a polycarbonate resin (trade name: Iupilon, manufactured by Mitsubishi Gas Chemical Co., Ltd.) After thoroughly mixing 7 parts by weight of the fluorine-based comb-type graft polymer resin (GF-300) purified by the above step and 550 parts by weight of monochlorobenzene, a high-pressure dispersing machine (trade name: Nanomizer, manufactured by Nanomizer Co., Ltd.) was used. To obtain a dispersion of tetrafluoroethylene resin particles.

Next, 500 parts by weight of a styryl compound having the following structural formula:

[0044]

Embedded image 500 parts by weight of a triarylamine compound having the following structural formula,

[0045]

Embedded image Polycarbonate resin (trade name: Iupilon Z200:
800 parts by weight of Mitsubishi Gas Chemical Co., Ltd.) and 1500 parts by weight of a tetrafluoroethylene resin particle dispersion were dissolved and mixed in 5000 parts by weight of monochlorobenzene and 3000 parts by weight of dichloromethane to prepare a coating liquid for a charge transport layer. This solution was applied onto the aluminum cylinder coated with the charge generating layer by dip coating, and dried at 130 ° C. for 50 minutes. The thickness of the charge transport layer was 25 μm.

The electrophotographic photoreceptor was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity with an electrophotographic photoreceptor tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential (surface potential after strong exposure) was measured 10,000 times in a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member is charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a high-quality image free from image defects was obtained both in the initial stage and on the 10,000th sheet.

On the other hand, the charge transporting layer of the electrophotographic photosensitive member was peeled off, and 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile, and this liquid was subjected to HPLC (high-performance liquid chromatography; pump L-6200, column ODS-4 × 250
mm, detector L-4200, data processor D-250
As a result of quantification of the quaternary ammonium salt with a sample No. 0, both manufactured by Hitachi, Ltd., 1 ppm of tetra-n-butylammonium bromide was detected. Therefore, 1
It was found that 00 ppm of the quaternary ammonium salt was contained.

Example 2 As a purification step of a fluorine-based comb type graft polymer resin, 800 parts by weight of a fluorine-based comb type graft polymer resin (trade name: LF-40, manufactured by Soken Chemical Co., Ltd.) was dropped at a rate of 50 cm ³ / min. And stirred dropwise into 9000 parts by weight of methanol. After the formed precipitate was separated from methanol by centrifugal filtration, the precipitate was dried at 60 ° C. for 24 hours using a vacuum dryer. Further, this fluorine-based comb-type graft polymer resin was dissolved in methyl ethyl ketone to a solid content of 15%, and this solution was dropped and stirred in 9000 parts by weight of methanol at a dropping rate of 50 cm ³ / min, and reprecipitated again. The resulting precipitate was separated and recovered from methanol by suction filtration, and then dried at 50 ° C. for 24 hours using a vacuum dryer to obtain a purified fluorine-based comb-type graft polymer resin.

Next, as a purification step of the tetrafluoroethylene resin particles, tetrafluoroethylene resin particles (trade name: Lubron L)
-2, manufactured by Daikin Industries, Ltd.)
Add 500 parts by weight of monochlorobenzene and stir for 30 minutes. Only the tetrafluoroethylene resin particles were separated and collected by a centrifugal separator, and then dried at 150 ° C. for 24 hours by a vacuum dryer to obtain purified tetrafluoroethylene resin particles.

Next, as a process for preparing a dispersion of tetrafluoroethylene resin particles, 100 parts by weight of tetrafluoroethylene resin particles (trade name: Lubron L-2, manufactured by Daikin Industries, Ltd.), 90 parts by weight of a resin (trade name: Panlite, manufactured by Teijin Chemicals Ltd.), 10 parts by weight of a fluorine-based comb graft polymer resin (FL-40) purified by the above process, and monochlorobenzene 55
After thoroughly mixing 0 parts by weight, the mixture was dispersed with a high-pressure dispersing machine (trade name: Nanomizer, manufactured by Nanomizer Co., Ltd.) to prepare a tetrafluoroethylene resin particle dispersion.

Using this tetrafluoroethylene resin particle dispersion, a coating solution for a charge transport layer was prepared in exactly the same manner as in Example 1. This solution was dip-coated on the same aluminum cylinder coated with the charge generation layer as in Example 1, and dried at 130 ° C. for 40 minutes. The thickness of the charge transport layer was 25 μm.

The electrophotographic photoreceptor was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photoreceptor tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a high-quality image free from image defects was obtained both in the initial stage and on the 10,000th sheet.

On the other hand, the charge transport layer of the electrophotographic photoreceptor was peeled off, 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile, and quantified by HPLC in the same manner as in Example 1. 50 ppm of tetra-n-butylammonium bromide and 30 ppm of tetra-n
-Ethyl ammonium bromide was detected. 80 in total
It was found that the quaternary ammonium salt was contained in ppm.

Example 3 As a step of purifying a fluorine-based comb type graft polymer resin, a fluorine-based comb type graft polymer resin (trade name: GF-150,
Toagosei Chemical Industries Co., Ltd.) 400 parts by weight of 30cm ³ a
The mixture was dropped and stirred in 6000 parts by weight of methanol at a dropping rate of / min. After the formed precipitate was separated from methanol by centrifugal filtration, the precipitate was dried at 60 ° C. for 24 hours using a vacuum dryer. After heating the fluorine-based comb-type graft polymer resin in a heating furnace at 150 ° C. for 1 hour, the fluorine-based comb-type graft polymer resin is further dissolved in methyl ethyl ketone to a solid content of 10%, and the solution is 30 cm ³ / m ^3.
The mixture was dropped and stirred in 6000 parts by weight of methanol at a dropping rate of "in", and reprecipitated and purified again. The resulting precipitate is separated and recovered from methanol by suction filtration, and then dried by a vacuum drier.
After drying at 24 ° C. for 24 hours, a purified fluorine comb type graft polymer resin was obtained.

Next, as a process for preparing a dispersion of poly (trifluorochloroethylene) resin particles, poly (trifluorochloroethylene) resin particles (trade name: Daiflon, manufactured by Daikin Industries, Ltd.) 10
0 parts by weight, 80 parts by weight of a polycarbonate resin, a fluorine-based comb type graft polymer resin (GF
-150) After sufficiently mixing 4 parts by weight of monochlorobenzene and 600 parts by weight of monochlorobenzene, the mixture was dispersed with a dispersing machine using glass beads (trade name: Sand Grinder, manufactured by Imex Co., Ltd.), and poly (trifluorochloroethylene) resin was obtained. A particle dispersion was prepared.

A coating solution for a charge transport layer was prepared in exactly the same manner as in Example 1 using this poly (trifluorochloroethylene) resin particle dispersion. This solution was dip-coated on the same aluminum cylinder coated with the charge generation layer as in Example 1,
And dried. The thickness of the charge transport layer was 25 μm. The electrophotographic photoreceptor is charged, exposed, and strongly exposed in an electrophotographic photoreceptor test machine (manufactured by Kawaguchi Electric Co., Ltd.) at 35 ° C. and 80% high temperature and high humidity for 0.5 seconds.
The change of the residual potential was measured 0000 times repeatedly. The results are shown in Table 1.

The electrophotographic photosensitive member is charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a high-quality image free from image defects was obtained both in the initial stage and on the 10,000th sheet.

On the other hand, the charge transport layer of the electrophotographic photoreceptor was peeled off, and 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile, and quantified by HPLC in the same manner as in Example 1. , 100 ppm of tetra-n-butylammonium bromide was detected.

Example 4 As a process for preparing a dispersion of polyvinylidene fluoride resin particles, 100 parts by weight of polyvinylidene fluoride resin particles (trade name: Daiel, manufactured by Daikin Industries, Ltd.), 70 parts by weight of polycarbonate resin, purified in Example 1. 9 parts by weight of the fluorinated comb-type graft polymer resin (GF-300) and 600 parts by weight of monochlorobenzene are sufficiently mixed, and then dispersed by a sand grinder using glass beads (manufactured by IMEX Co., Ltd.). A resin particle dispersion was prepared.

Using this polyvinylidene fluoride resin particle dispersion, a coating solution for a charge transport layer was prepared in exactly the same manner as in Example 1. This solution was dip-coated on the same aluminum cylinder coated with the charge generation layer as in Example 1, and dried at 130 ° C. for 60 minutes. The thickness of the charge transport layer was 25 μm. The electrophotographic photoreceptor was charged, exposed and strongly exposed in an electrophotographic photoreceptor tester (manufactured by Kawaguchi Electric Co., Ltd.) at 35 ° C. and 80% high temperature and high humidity at a cycle of 1000 for 0.5 seconds.
The change in the residual potential was measured repeatedly 0 times. The results are shown in Table 2.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a high-quality image free from image defects was obtained both in the initial stage and on the 10,000th sheet.

On the other hand, the charge transport layer of the electrophotographic photoreceptor was peeled off, 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile, and quantified by HPLC in the same manner as in Example 1. In this case, 40 ppm of tetra-n-butylammonium bromide was detected.

Example 5 The same styryl compound as in Example 1, 1200 parts by weight, a polycarbonate resin (1000 parts by weight), monochlorobenzene (5,000 parts by weight), and dichloromethane (3,000 parts by weight) were dissolved and mixed to prepare a charge transport layer coating solution. This liquid was applied by dip-coating the coating material for a charge transport layer on an aluminum cylinder coated with a charge generation layer as in Example 1, and dried at 130 ° C. for 40 minutes. The thickness of the charge transport layer was 20 μm.

Next, as a process for preparing a dispersion of tetrafluoroethylene resin particles, 50 parts by weight of a styryl compound and tetrafluoroethylene resin particles (trade name: Lubron L-
2, manufactured by Daikin Industries, Ltd.) (washing and purifying three times by the method of Example 2) 50 parts by weight, 120 parts by weight of polycarbonate resin, fluorine-based comb type graft polymer resin (GF-300) 4 purified in Example 1 Parts by weight and monochlorobenzene 5
After thoroughly mixing 00 parts by weight, the mixture was dispersed by a sand grinder (manufactured by Imex Co., Ltd.) using glass beads to prepare a dispersion of tetrafluoroethylene resin particles.

Further, the dispersion liquid of the tetrafluoroethylene resin particles was spray-coated on the photosensitive drum coated with the charge transport layer, and dried at 130 ° C. for 10 minutes to provide a protective layer. The thickness of the protective layer was 4 μm.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a high-quality image free from image defects was obtained both in the initial stage and on the 10,000th sheet.

On the other hand, the protective layer of the electrophotographic photoreceptor was peeled off, 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile, and quantified by HPLC in the same manner as in Example 1. As a result, 95 ppm of tetra-n was obtained. -Butyl ammonium bromide was detected.

Example 6 As a step of purifying a fluorine-based comb type graft polymer resin, a fluorine-based comb type graft polymerization resin [methyl methacrylate as a macromonomer and a compound represented by the above formula (4) as a fluorine-based polymerizable monomer were grafted. Copolymerized fluorine comb type graft polymer resin (fluorine content 23
500% by weight) was dropped and stirred into 9000 parts by weight of methanol at a rate of 150 cm ³ / min.
After the formed precipitate was separated from methanol by centrifugal filtration, the precipitate was dried at 60 ° C. for 24 hours using a vacuum dryer. Further, this fluorine-based comb type graft polymer resin is dissolved in methyl ethyl ketone to a solid content of 25%,
The mixture was dropped and stirred in 9000 parts by weight of methanol at a dropping rate of 0 cm ³ / min, and reprecipitated again. The resulting precipitate was separated and recovered from methanol by suction filtration, and then dried at 50 ° C. for 24 hours using a vacuum dryer to obtain a purified fluorine-based comb-type graft polymer resin.

Next, as a process for preparing a dispersion of tetrafluoroethylene resin particles, tetrafluoroethylene resin particles (trade name: Lubron L-2, manufactured by Daikin Industries, Ltd.) (purified by the method of Example 2) 100 parts by weight, 90 parts by weight of a polycarbonate resin (trade name: Panlite, manufactured by Teijin Chemicals Ltd.), 10 parts by weight of a fluorine-based comb-type graft polymer resin purified by the above process, and 550 parts by weight of monochlorobenzene were sufficiently mixed. Thereafter, the mixture was dispersed with a high-pressure dispersing machine (trade name: Nanomizer, manufactured by Nanomizer Co., Ltd.) to prepare a tetrafluoroethylene resin particle dispersion.

Using this tetrafluoroethylene resin particle dispersion, a coating solution for a charge transport layer was prepared in exactly the same manner as in Example 1. This solution was dip-coated on the same aluminum cylinder coated with the charge generation layer as in Example 1, and dried at 130 ° C. for 40 minutes. The thickness of the charge transport layer was 25 μm.

The electrophotographic photosensitive member was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photosensitive member tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a high-quality image free from image defects was obtained both in the initial stage and on the 10,000th sheet.

The charge transport layer of the electrophotographic photosensitive member was peeled off,
1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile and quantified by HPLC in the same manner as in Example 1.
50 ppm of tetra-n-butylammonium iodide and 30 ppm of tetraethylammonium chloride were detected in the charge transport layer. 4th of total 80ppm
It was found that a quaternary ammonium salt was contained.

Comparative Example 1 The procedure of Example 1 was repeated except that in the purification step of the fluorine-based comb-type graft polymer resin of Example 1, only one reprecipitation purification was used without performing the second or subsequent reprecipitation purification. An electrophotographic photoreceptor was prepared in exactly the same manner.

The electrophotographic photosensitive member was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photosensitive member tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the change in the residual potential, it was higher than the initial value.

On the other hand, the charge transport layer of the electrophotographic photoreceptor was peeled off, 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile, and quantified by HPLC in the same manner as in Example 1. n-Butyl ammonium bromide was detected.

Comparative Example 2 In the purification step of the fluorine-based comb type graft polymer resin of Example 1, the same procedure as in Example 1 was carried out except that only the reprecipitation purification was performed twice without performing the third reprecipitation purification. An electrophotographic photosensitive member was prepared in the same manner.

The electrophotographic photosensitive member was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photosensitive member tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the change in the residual potential, it was higher than the initial value.

On the other hand, the charge transport layer of the electrophotographic photoreceptor was peeled off, 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile, and quantified by HPLC in the same manner as in Example 1. As a result, 130 ppm of tetra- n-Butyl ammonium bromide was detected.

Comparative Example 3 In the purification step of the fluorine-based comb type graft polymer resin of Example 2, the procedure was the same as that of Example 1 except that the second reprecipitation purification was carried out without the second reprecipitation purification. An electrophotographic photosensitive member was prepared in the same manner.

The electrophotographic photoreceptor was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photoreceptor testing machine (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the change in the residual potential, it was higher than the initial value.

On the other hand, the charge transport layer of the electrophotographic photoreceptor was peeled off, and 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile and quantified by HPLC in the same manner as in Example 1. n-Butyl ammonium bromide and 50 ppm of tetra-n-ethyl ammonium bromide were detected. 4th of 140 ppm in total
It was found that a quaternary ammonium salt was contained.

Comparative Example 4 In the purification step of the fluorine-based comb type graft polymer resin of Example 3, reprecipitation purification 1 was performed without performing the step of heating and reprecipitation again.
An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 3 except that a fluorine-based comb-type graft polymer resin was used.

The electrophotographic photosensitive member was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photosensitive member tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the change in the residual potential, it was higher than the initial value.

The charge transport layer of the electrophotographic photosensitive member was peeled off,
1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile and quantified by HPLC in the same manner as in Example 1.
150 ppm of tetra-n-butylammonium bromide was detected in the charge transport layer.

Comparative Example 5 In the purification step of the fluorine-based comb type graft polymer resin of Example 3, except that the step of heating the resin was not performed and only the re-precipitation purification was performed twice, a fluorine-based comb type graft polymer resin was used. An electrophotographic photosensitive member was prepared in exactly the same manner as in Example 3.

The electrophotographic photosensitive member was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photosensitive member tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the change in the residual potential, it was higher than the initial value.

The charge transport layer of the electrophotographic photosensitive member was peeled off,
1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile and quantified by HPLC in the same manner as in Example 1.
120 ppm of tetra-n-butylammonium bromide was detected in the charge transport layer.

Comparative Example 6 In the step of purifying a fluorine-based comb type graft polymer resin,
An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 4, except that a fluorine-based comb-type graft polymer resin (GF-300), which was subjected to reprecipitation and purification only once as in Comparative Example 1, was used.

The electrophotographic photosensitive member was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photosensitive member tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the change in the residual potential, it was higher than the initial value.

The charge transport layer of the electrophotographic photosensitive member was peeled off,
1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile and quantified by HPLC in the same manner as in Example 1.
150 ppm of tetra-n-butylammonium bromide was detected in the charge transport layer.

Comparative Example 7 In the step of purifying the fluorine-based comb type graft polymer resin of Example 5, a fluorine-based comb-type graft polymer resin (GF-300), which was subjected to reprecipitation and purification only once as in Comparative Example 1, was used. An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 5, except for using it.

The electrophotographic photoreceptor was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photoreceptor testing machine (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1. This electrophotographic photoreceptor was attached to a copying machine in which charging, exposure, development, transfer and cleaning processes were repeated in a 0.5 second cycle,
Under 80% high temperature and high humidity, 10,000 copies were continuously made. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the change in the residual potential, it was higher than the initial value.

The protective layer of the electrophotographic photoreceptor was peeled off, and 1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile and quantified by HPLC in the same manner as in Example 1.
0 ppm of tetra-n-butylammonium bromide was detected.

Comparative Example 8 In the step of purifying the fluorine-based comb type graft polymer resin of Example 6, the procedure was the same as in Example 6 except that the fluorine-based comb type graft polymer resin was used only once for reprecipitation purification. To produce an electrophotographic photoreceptor.

The electrophotographic photosensitive member was charged, exposed and strongly exposed at 35 ° C. and 80% high temperature and high humidity by an electrophotographic photosensitive member tester (manufactured by Kawaguchi Electric Co., Ltd.).
The change in the residual potential was measured 10,000 times with a 5-second cycle. The results are shown in Table 1. This electrophotographic photoreceptor was attached to a copying machine in which charging, exposure, development, transfer and cleaning processes were repeated in a 0.5 second cycle,
Under 80% high temperature and high humidity, 10,000 copies were continuously made. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the change in the residual potential, it was higher than the initial value.

The charge transport layer of the electrophotographic photosensitive member was peeled off,
1 part by weight of the pulverized powder was extracted with 99 parts by weight of acetonitrile and quantified by HPLC in the same manner as in Example 1.
130 ppm of tetra-n-butylammonium iodide and 40 ppm of tetraethylammonium chloride were detected in the charge transport layer. It was found that a total of 170 ppm of the quaternary ammonium salt was contained.

Comparative Example 9 An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that in the preparation step of the charge transport layer of Example 1, the following composition was used without adding the tetrafluoroethylene resin particle dispersion. did.

1000 parts by weight of styryl compound, 1200 parts by weight of polycarbonate resin (trade name: Iupilon, manufactured by Mitsubishi Gas Chemical Co., Ltd.), 610 tetrahydrofuran
0 parts by weight, 3000 parts by weight of dichloromethane.

The electrophotographic photosensitive member was charged, exposed, developed,
The process of transferring and cleaning was repeated in a 0.5 second cycle, and the copying machine was mounted on a copying machine at 35 ° C. and 80% high temperature and high humidity for continuous copying of 10,000 sheets. As a result, a good image was obtained in the initial stage, but fog occurred on the 10,000th sheet, and no good image was obtained. As a result of measuring the thickness of the charge transport layer, it was found that the 10,000th sheet had already been worn to 7 μm.

Comparative Example 10 A dispersion was prepared in the same manner as in Example 1 except that no fluorine-based comb type graft polymer resin was added in the step of preparing the tetrafluoroethylene resin particle dispersion. As a result, the dispersion liquid became gel due to poor dispersion. An electrophotographic photoreceptor was prepared using this tetrafluoroethylene resin particle dispersion in the same manner as in Example 1. However, a large number of spot-like fogs were generated from the initial stage, and a good image was not obtained. As a result of observing the surface of the electrophotographic photosensitive member, a large number of aggregates of tetrafluoroethylene resin particles were found.

Example 1, Example 2, Example 3, Example 4, Example 5, Example 6 and Comparative Example 1, Comparative Example 2, Comparative Example 3, Comparative Example 4, Comparative Example 5, Comparative Example 6 Comparing Comparative Example 7 and Comparative Example 8, the amount of quaternary ammonium salt contained in the surface layer of the electrophotographic photoreceptor in which the surface layer contains fluorine-based resin particles and fluorine-based comb-type graft polymerized resin is Those having a concentration of 100 ppm or less have a small increase in the residual potential due to repeated charging and exposure, and are not only stable in potential even when the charging, exposure, development, transfer and cleaning processes are repeated, but also the 10,000th sheet in the initial stage. Also, a high-quality image without image defects was obtained. However, when the amount of the quaternary ammonium salt contained in the surface layer is 1
When the content exceeds 00 ppm, the residual potential was increased after repeated use, and image fogging occurred.

On the other hand, in the surface layer containing no fluorine resin particles as in Comparative Example 9, the abrasion resistance was poor, and the surface layer was worn by repeated use. Comparative Example 10
When only the fluorine-based resin particles were used and the fluorine-based comb-type graft polymer resin was not contained, the fluorine-based resin particles did not disperse well and a good surface layer could not be obtained.

[0112]

[Table 1]

[0113]

As is apparent from the above, the electrophotographic photoreceptor of the present invention and the electrophotographic apparatus having the same have durability against abrasion and scratches on the surface due to friction, and remain in a high humidity environment. There is no increase in potential, and a high-quality image can be formed stably.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a transfer type electrophotographic apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drum type photoreceptor 1a shaft 2 Charging means 3 Exposure part 4 Developing means 5 Transfer means 6 Cleaning means 7 Pre-exposure means 8 Image fixing means 9 Transfer material L Optical image exposure

Continuation of the front page (56) References JP-A-63-311356 (JP, A) JP-A-63-221355 (JP, A) JP-A-62-87966 (JP, A) JP-A-55-142359 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 5/147

Claims (5)

(57) [Claims] 1. An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the surface layer contains fluorine-based resin particles and a fluorine-based comb-type graft polymer resin, wherein the quaternary ammonium in the surface layer is provided. An electrophotographic photoreceptor, wherein the salt content is 100 ppm or less based on the total weight of the solid content of the surface layer. Wherein said fluorine-based comb type graft polymerization resin, acrylic acid esters, methacrylic acid esters and is Ru macromonomer selected from the group consisting of styrene compounds,
2. The electrophotographic photoreceptor according to claim 1 , wherein the electrophotographic photoreceptor is graft-copolymerized from perfluoroalkylethyl methacrylate. 3. The electrophotographic photoconductor according to claim 1, wherein the quaternary ammonium salt is tetrabutylammonium bromide. 4. The electrophotographic apparatus, comprising an electrophotographic photosensitive member according to any one of claims 1-3. 5. The electronic photograph according to claim 1, wherein:
True photoconductor, charging means, developing means and cleaning
At least one member selected from the group consisting of
And is detachable from the main body of the electrophotographic apparatus.
An apparatus unit, characterized in that: