JP3402970B2 - Electrophotographic photoreceptor, process cartridge having the electrophotographic photoreceptor, and electrophotographic apparatus - 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 photoreceptor, a process cartridge equipped with the electrophotographic photoreceptor, and an electrophotographic apparatus.

[0002]

BACKGROUND OF THE INVENTION Electrophotography is described in US Pat. No. 2,297,691.
As disclosed in Japanese Unexamined Patent Publication (Kokai), a photoconductive material is used whose electric resistance changes according to the amount of irradiation received during image exposure and which is composed of a support coated with an insulating substance in a dark place. . The basic characteristics required for an electrophotographic photosensitive member using this photoconductive material are (1) being able to be charged to an appropriate potential in a dark place, (2) being small in dissipation of a charge in a dark place, ( 3) It is possible to rapidly dissipate the charge by light irradiation.

Conventionally, as an electrophotographic photosensitive member, an inorganic photosensitive member having a photosensitive layer containing an inorganic photoconductive compound such as selenium, cadmium sulfide and zinc oxide as a main component has been widely used. However, although these satisfy the above conditions (1) to (3), they are not necessarily satisfactory in terms of thermal stability, moisture resistance, durability, productivity, and the like. For example, when selenium is crystallized, the characteristics as a photoreceptor are deteriorated, so that it is difficult to manufacture and selenium causes crystallization of heat and cancowite citrate to deteriorate the performance as a photoreceptor. Further, cadmium sulfide has problems in moisture resistance and durability, and zinc oxide has problems in smoothness, hardness, and abrasion resistance. Further, most of the inorganic photoconductors have a limited photosensitive wavelength region. For example, the photosensitive wavelength region of selenium is the blue region, and it has almost no sensitivity in the red region. Therefore, various methods have been proposed to extend the photosensitivity to the long wavelength region, but there are many restrictions on the selection of the photosensitivity wavelength region. Even when zinc oxide or cadmium sulfide is used as a photoconductor, the photosensitive wavelength range of itself is narrow, and it is necessary to add various sensitizers.

In recent years, electrophotographic photoreceptors using various organic photoconductive compounds have been actively developed for the purpose of overcoming the disadvantages of these inorganic photoreceptors. For example, U.S. Pat. No. 3,837,851 discloses a photoreceptor having a charge transport layer containing triallyl pyrazoline, U.S. Pat. No. 3,870,370.
No. 882, there is already known a photoreceptor or the like comprising a charge generation layer made of a derivative of a perylene pigment and a charge transport layer made of a condensation product of 3-propylene and formaldehyde.

Further, as a photoreceptor using a bisazo pigment or a trisazo pigment as a charge generating material, JP-A-59-3
3445, JP-A-56-46237, JP-A-60-111249 and the like are already known.

Further, the organic photoconductive compound can freely select the photosensitive wavelength region of the electrophotographic photosensitive member depending on the compound. For example, regarding azo organic pigments, JP-A-61-272754 and JP-A-56-16.
The substance disclosed in Japanese Patent No. 7759 includes a substance having high sensitivity in the visible region, and is disclosed in JP-A-57-195.
The substances disclosed in Japanese Patent No. 767 and Japanese Patent Application Laid-Open No. 61-228453 include those having sensitivity in the infrared region.

Among these materials, materials having sensitivity in the infrared region are used in laser beam printers, LED printers and the like, which have made remarkable progress in recent years, and their demand frequency is increasing.

An electrophotographic photoreceptor using these organic photoconductive compounds is used as a function-separated photoreceptor in which a charge generation layer and a charge transport layer are laminated in order to satisfy both electric and mechanical properties. Often. On the other hand, as a matter of course, it is required that the electrophotographic photosensitive member has sensitivity, electrical characteristics, and optical characteristics according to the electrophotographic process applied to the electrophotographic photosensitive member. Especially for electrophotographic photoreceptors that are repeatedly used, the surface layer of the photoreceptor is corona charged,
Since external electrical and mechanical forces such as direct charging, toner development, transfer process, and surface cleaning are directly applied, durability against them is also required. Specifically, the surface is abraded by electrical deterioration due to ozone or nitrogen oxides during charging, discharge during charging and rubbing of the cleaning member,
Durability against mechanical deterioration such as scratches is required.

The surface of the electrophotographic photosensitive member is generally composed of a charge transport material and a resin layer, and is a fairly thin film. Of the above-mentioned drawbacks, mechanical deterioration is largely due to the resin layer,
The choice of this resin layer is very important.

A polycarbonate resin having bisphenol Z as a skeleton is one having durability as described above. This polycarbonate Z resin (hereinafter abbreviated as PCZ) is superior in mechanical strength to the conventionally used polycarbonate A resin and exhibits good solubility in various organic solvents. It has the characteristics mentioned.

However, even if the above points are solved, the following problems still remain. (1) It is vulnerable to solvent cracks caused by the organic solvent or oil adhering to the surface. (2) When the formed coating film main body does not show good lubricity, the electrophotographic photosensitive member is liable to be scratched, resulting in image defects, and cleaning failure and cleaning due to early deterioration of the cleaning blade. -Insufficient cleaning may occur due to reversal of the blade.

[0012] In PCZ, volume shrinkage is large during coating film formation, particularly when coating from a solution by a casting method, and stress is often left inside the coating film. Therefore, it has a drawback that it is relatively weak against stress corrosion. In order to solve this, for example, in JP-A-61-62040, a polycarbonate A resin and PCZ are mixed, and in JP-A-61-62039, a bisphenol A resin is used.
Although a method for reducing stress corrosion cracking by copolymerizing bisphenol Z with bisphenol Z is disclosed, none of them is sufficient for solvent cracking.

Further, as described in (2) above, the ordinary polycarbonate resin has a low lubricity against the cleaning blade used in the electrophotographic process, and the cleaning blade has a low lubricity. However, it has been pointed out that there is a problem in that it is reversed due to the progress of durability, which causes a cleaning failure and a scratch is generated due to a strong force applied to the electrophotographic photosensitive member. In order to improve this, a method of adding Si oil, or a method of copolymerizing a polydimethylsiloxane block with a polycarbonate resin as disclosed in JP-A-61-1293954, and JP-A-63-63.
The -65444 discloses bisphenol - method used to change the center of Le A a (CH _{3) 2} -C = moiety (CF _{3) 2} -C = is disclosed. However, in the method of adding Si oil, electrophotographic characteristics, specifically sensitivity,
It adversely affects various characteristics such as residual potential. Moreover, there is a drawback that the Si oil in the surface layer is lost due to the progress of durability, and permanent lubricity cannot be obtained.

Further, when the above-mentioned methyl siloxane block copolymerized resin or a resin containing a fluorine-based bisphenol is used, the lubricity is improved, but these polymers are soluble. However, there were drawbacks such as white turbidity and gelation during coating, and surface roughness and reduction in mechanical strength when used as the surface layer of an electrophotographic photoreceptor.

[0015]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the conventional electrophotographic photoreceptor having a polycarbonate resin as a surface layer, and to improve lubricity and rubbing. It is an object of the present invention to provide an electrophotographic photosensitive member which has improved memory properties, maintains film strength, has good solvent cracking properties, and is easy to manufacture. Another object of the present invention is to provide a process cartridge having the electrophotographic photoreceptor and an electrophotographic apparatus.

[0016]

The present invention is an electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer is
It has a charge generation layer and a charge transport layer, and the charge transport layer is a surface layer.
In the electrophotographic photosensitive member which is a surface layer, the surface layer is a polymer having a constitutional unit represented by the following general formula (1), a general formula (1)

[Chemical 3] [In the formula, A is —CR ₃ R ₄ — (provided that R ₃ and R ₄ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms), and 5 to 5 carbon atoms which may be substituted. 11-1,1-
A cycloalkyl group, an α, ω-alkylene group having 2 to 10 carbon atoms, a single bond, —O—, —S—, wherein R ₁ and R ₂ are a hydrogen atom, a halogen atom, or an optionally substituted alkyl group Represents an optionally substituted aryl group. ] And a copolymer in which one or more kinds of the structural unit represented by the general formula (1) is branched by an ester bond is contained, and at the end of the copolymer, all hydrogen atoms are substituted with fluorine atoms. It is composed of an electrophotographic photoreceptor having a phenyl group.

Table 1 shows examples of constitutional units represented by the general formula (1).
However, the present invention is not limited to these.

[Table 1]

Examples of preferred structural units include structural unit examples 1, 2 and 8, and structural unit example 1 is particularly preferred.

The polymer having the constitutional unit represented by the general formula (1) is a compound represented by the following general formula (5) as a terminal terminating agent when polymerizing the bisphenol represented by the following general formula (4). Is synthesized by using. General formula (4)

[Chemical 5] [In the formula, A is —CR ₃ R ₄ — (wherein R ₃ and R ₄ are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms), or an optionally substituted carbon atom having 5 to 5 carbon atoms. 11-1,1-
A cycloalkyl group, an α, ω-alkylene group having 2 to 10 carbon atoms, a single bond, —O—, and —S—, and R ₁ and R ₂
Represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group, or an optionally substituted aryl group. ] General formula (5)

[Chemical 6] (In the formula, B represents a single bond or a straight chain having 1 to 3 carbon atoms.)

Further, by making at least one of the constitutional units represented by the general formula (1) contained in the copolymer the same as the constitutional units of the polymer, the compatibility between the polymer and the copolymer is reduced. Therefore, it is preferable to have the same structural portion.

The electrophotographic photoreceptor of the present invention has particularly excellent solvent crack resistance, surface lubricity, and storage stability because the introduction of a substance having a chemical resistant terminal portion into the surface layer. It is considered that, by doing so, the rate at which the chemical agent that causes the solvent crack penetrates into the photosensitive layer is reduced, and the rate at which an abnormality occurs in the coating is reduced. When a homopolymer having the same structure as that of the constituent unit is blended, the effect of relaxing the internal stress is enhanced, and the solvent crack resistance is further improved. Further, by adopting this structure, the effect that the polymer and the oligomer are compatible with each other and the trap of the electric charge is reduced can be obtained.

Next, layer separation by deposition of low-molecular components added to the photosensitive layer is carried out. This is because a fluorine atom having a large electronegativity is introduced into the terminal, so that
It is considered that the charge transport material becomes difficult to move because it functions as a compatibilizer.

The polymer or copolymer contained in the surface layer of the electrophotographic photosensitive member of the present invention is determined in consideration of scratch resistance, hardness, manufacturing stability, storage stability and the like required according to the electrophotographic process. It must be. In that case, the weight ratio to the total binder resin used in the charge transport layer is 0.0
It is preferably in the range of 1 to 30% by weight, and 0.01
Especially preferred is a range of -15% by weight.

Next, the structure of the electrophotographic photosensitive member of the present invention will be described. As the conductive support, any material having conductivity may be used, and examples thereof include metals such as aluminum and stainless steel, metals provided with a conductive layer, plastics, paper, and the like, and examples of the shape include a cylindrical shape or a film shape. .

When the image input such as a laser beam printer is laser light, a conductive layer may be provided for the purpose of preventing interference fringes due to scattering or covering scratches on the support.
This can be formed by dispersing conductive powder such as carbon black or metal particles in a binder resin. The thickness of the conductive layer is 5 to 40 μm, preferably 10 to 30 μm.

An intermediate layer having an adhesive function is provided on the conductive support or the conductive layer. Examples of the material for the intermediate layer include polyamide, polyvinyl alcohol, polyethylene oxide, ethyl cellulose, casein, polyurethane, and polyether urethane. The intermediate layer is formed by dissolving these materials in a suitable solvent and applying them. The film thickness is 0.1-5 μm, preferably 0.3-1 μm
Is appropriate.

On the intermediate layer, a coating solution prepared by dispersing a charge generating material such as a phthalocyanine pigment, an azo pigment and an anthanthrone pigment in a binder resin dissolved in a solvent is applied and dried to form the charge generating layer. Form.

Examples of the binder resin include polyester resin, polyacrylic resin, polyvinylcarbazole resin, phenoxy resin, polycarbonate resin, polystyrene resin, polyvinylacetate resin, polysulfone resin and polyarylate. Resins, vinylidene chloride-acrylonitrile copolymer resins, polyvinylbenzal resins and the like can be mentioned. The ratio of binder resin to pigment is 1/1 to 10
/ 1, preferably 1.5 / 1 to 3/1.

The charge transport layer is mainly formed by coating and drying a coating solution in which a charge transport material and a binder resin are dissolved in a solvent. Examples of the charge transport material include various triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, triallylmethane compounds, thiazole compounds and the like. As the binder resin, the same resin as used in forming the charge generation layer can be used.

The present invention integrally supports the electrophotographic photoreceptor of the present invention and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means, and is attachable to and detachable from the main body of the electrophotographic apparatus. It is composed of a process cartridge characterized by being flexible.

The present invention also comprises an electrophotographic apparatus characterized by having the electrophotographic photosensitive member of the present invention, a charging means, an image exposing means, a developing means and a transferring means.

FIG. 5 shows a schematic structure of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention. In the figure, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is rotationally driven at a predetermined peripheral speed in the direction of an arrow around the lever 2. In the course of rotation of the photoconductor 1, the peripheral surface of the photoconductor 1 is uniformly charged to a predetermined positive or negative potential by a primary charging means 3, and then an image exposure means (non-exposure means) such as slit exposure or laser beam scanning exposure is used. Image exposure light 4 from the drawing is received. In this way, electrostatic latent images are sequentially formed on the peripheral surface of the photoconductor 1.

The formed electrostatic latent image is then developed by the developing means 5.
The toner-developed toner image developed and developed by the transfer material 7 is fed from a sheet feeding unit (not shown) between the photoconductor 1 and the transfer unit 6 in synchronization with the rotation of the photoconductor 1. Then, the image is sequentially transferred by the transfer means 6. The transfer material 7 that has received the image transfer is separated from the surface of the photoconductor and is introduced into the image fixing means 8 to undergo the image fixing, and is printed out as a copy (copy) to the outside of the apparatus. The surface of the photoreceptor 1 after the image transfer is cleaned by the cleaning means 9 after removal of the residual toner after transfer, and is further neutralized by the pre-exposure light 10 from the pre-exposure means (not shown). And then repeatedly used for image formation. If the primary charging means 3 is a contact charging means using a charging roller or the like, pre-exposure is not always necessary.

In the present invention, among the constituent elements such as the photoconductor 1, the primary charging means 3, the developing means 5 and the cleaning means 9 described above, a plurality of constituent elements are integrally combined as a process cartridge. However, the process cartridge may be detachably attached to the main body of the electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging means 3, the developing means 5 and the cleaning means 9 is integrally supported together with the photoconductor 1 to form a cartridge, and a guide means such as a rail 12 of the apparatus main body is used. The process cartridge 11 can be detachably attached. When the electrophotographic apparatus is a copying machine or a printer, the image exposure light 4 uses reflected light or transmitted light from the document, or the document is read by a sensor, converted into a signal, and the image is read according to this signal. The light emitted by the laser beam scanning, the driving of the LED array, the driving of the liquid crystal shutter array, and the like.

On the other hand, when used as a printer for a facsimile, the image exposure light 4 becomes exposure light for printing the received data. FIG. 6 is a block diagram showing an example of this case. The controller 14 controls the image reading unit 13 and the printer 22. The entire controller 14 is controlled by the CPU 20. The read data from the image reading unit 13 is transmitted to the partner station through the transmission circuit 16. The data received from the partner station is sent to the printer 22 through the receiving circuit 15. Predetermined image data is stored in the image memory. The printer controller 21 controls the printer 22. 17
Is a telephone. The image received from the line 18 (image information from the remote terminal connected via the line) is demodulated by the receiving circuit 15, and then the image information is decoded by the CPU 20 and sequentially stored in the image memory 19. To be done. When the image of at least one page is stored in the image memory 19, the image of that page is recorded. The CPU 20 reads out one page of image information from the image memory 19 and sends the decoded one page of image information to the printer-controller-21. Upon receiving the image information of one page from the CPU 20, the printer controller 21 controls the printer 22 to record the image information of the page. CPU20
Is receiving the next page while the printer 22 is recording. In this way, the image is received and recorded.

[0036]

BEST MODE FOR CARRYING OUT THE INVENTION The electrophotographic photosensitive member of the present invention is prepared, for example, as follows.

Aluminum cylinder-tin oxide on top
A coating solution prepared from titanium oxide, titanium oxide, phenol resin, silicone oil, and methanol / methyl cellosolve is applied to form a conductive layer, and then copolymerized with N-methoxymethylated nylon. A solution of nylon dissolved in methanol and n-butanol is applied on the conductive layer to form an intermediate layer. Next, oxytitanium phthalocyanine, polyvinyl butyral and cyclohexanone are dispersed by a sand mill, and further, Methyl ethyl ketone was added to prepare a charge generation layer dispersion, which was then dip-coated on the intermediate layer to form a charge generation layer.
LeZ polycarbonate resin is dissolved in monochlorobenzene and dichloromethane, and the prepared solution is applied onto the charge generation layer by dip coating and dried to form a charge transport layer, thereby preparing an electrophotographic photoreceptor.

The cartridge of the present invention integrally supports the electrophotographic photosensitive member of the present invention and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means. It is designed to be removable from the body of the photographic device.

In the electrophotographic apparatus having the process cartridge having the electrophotographic photosensitive member of the present invention, the drum-shaped electrophotographic photosensitive member of the present invention is rotationally driven at a predetermined peripheral speed. In the course of rotation of the photosensitive member, its peripheral surface is uniformly charged with a predetermined positive or negative potential by the primary charging means, and then image exposure from the image exposing means such as slit exposure or laser beam scanning exposure is performed. Upon receiving light, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor, and the formed electrostatic latent image is then toner-developed by the developing means.
The developed image is sequentially transferred by the transfer unit to the transfer material that is fed from the paper feeding unit between the photosensitive member and the transfer unit in synchronization with the rotation of the photosensitive member. The transfer material which has received the image transfer is separated from the surface of the photoconductor and is introduced into the image fixing means to undergo the image fixing, so that it is printed out as a copy (copy) outside the apparatus. The surface of the photoconductor after the image transfer is clear.
After the transfer residual toner is removed by the cleaning means, the surface is cleaned, and the charge is removed by the pre-exposure light from the pre-exposure means. Then, the toner is repeatedly used for image formation.

[0040]

【Example】

Example 1 An aluminum cylinder of 30θ, 260 mm was used as a support, and 10 parts of titanium oxide treated with tin oxide coat (parts by weight, the same hereinafter), 10 parts of titanium oxide, 10 parts of phenol resin, and silicone oil were placed on the support. A coating material prepared from 0.001 part of methanol / methyl cellosolve (1/1) was applied by a dipping method and heat-cured at 140 ° C. for 30 minutes to form a conductive layer of 15 μm.

Then, a solution prepared by dissolving 3 parts of N-methoxymethylated nylon and 3 parts of copolymerized nylon in 65 parts of methanol and 350 parts of n-butanol was applied thereon by a dipping method to form a film. An intermediate layer having a thickness of 0.5 μm was formed.

Next, the diffraction angles 2θ ± 0.2 ° in the X-ray diffraction spectrum of CuKα are 9.0 °, 14.2 °, 2
1 part of 4 parts of oxytitanium phthalocyanine having a strong peak at 3.9 ° and 27.1 °, 2 parts of polyvinyl butyral (trade name S-REC BM-2, manufactured by Sekisui Chemical Co., Ltd.) and 80 parts of cyclohexanone are φ1 mm. After being dispersed for 4 hours by a sand mill using glass beads, 115 parts of methyl ethyl ketone was added to prepare a dispersion liquid for a charge generation layer.
This dispersion was applied on the above intermediate layer by a dipping method to give a film thickness of 0.
A 3 μm charge generation layer was formed.

Next, 7 parts of an amine compound having the following structural formula,

[Chemical 7] 3 parts of an amine compound having the following structural formula,

[Chemical 8] 9 parts of Bisphenol Z polycarbonate resin (viscosity average molecular weight 22000) and 1 part of Polymerization Example 1 shown in Table 2 below were dissolved in 50 parts of chlorobenzene and 10 parts of dichloromethane to prepare a coating liquid for charge transport layer. Was prepared. This coating solution was applied on the charge generation layer by a dipping method and dried at 110 ° C. for 1 hour to form a charge transport layer having a film thickness of 25 μm, thereby preparing an electrophotographic photoreceptor.

[0044]

[Table 2]

Examples 2 to 3 Electrophotographic photoreceptors were prepared in the same manner as in Example 1 except that Polymerization Examples 2 and 3 were used instead of Polymerization Example 1.

Using the electrophotographic photosensitive members prepared in Examples 1 to 3 , surface lubricity and solvent crack resistance were measured. Regarding the surface lubricity, a polyurethane resin cleaning blade for a copying machine was used, which was brought into contact with the surface of the photoconductor at a contact angle of 30 degrees, and the sliding resistance thereof was changed to HEIDON-1.
It measured using the 4 type surface property tester (made by Shinto Scientific Co., Ltd.). Regarding the solvent cracking property, finger grease was adhered to this surface layer and left for 24 hours and 2 days at 25 ° C. and 60% RH, and then the presence or absence of solvent cracking was observed by a microscope.

Further, this electrophotographic photosensitive member was subjected to 9 ° C. at 9 ° C.
After being left under 5% RH for 24 hours, L manufactured by Canon Inc.
It was placed in BPNX and subjected to paper passing for 15,000 sheets, and black spots caused by toner adhering to the surface of the photoconductor were observed.

Next, after the blades were rubbed and abutted and left for 24 hours, it was observed whether or not a rubbing memory of the abutted portion of the blade appeared in the image. The results are shown in Tables 3 and 4.

[0049]

[Table 3]

[0050]

[Table 4]

Comparative Examples 1 and 2 The binder resins for the charge transport layer were prepared under the conditions 1 and 2 shown in Table 5 below.
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that. The results are shown in Tables 6 and 7.

[0052]

[Table 5]

[0053]

[Table 6]

[Table 7]

Examples 4 to 5 Table 8 shows the binder resins used in the charge transport layer in Example 1.
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the combinations shown in 9 and 9 were replaced. The results are shown in Tables 10 and 11.

[0055]

[Table 8]

[0056]

[Table 9]

[0057]

[Table 10]

[0058]

[Table 11]

[0059]

The electrophotographic photosensitive member of the present invention has remarkable effects on lubricity, solvent crack resistance and rubbing memory characteristics. Further, a remarkable effect can be obtained in a process cartridge having the electrophotographic photosensitive member and an electrophotographic apparatus.

[Brief description of drawings]

FIG. 1 is a process chart having an electrophotographic photoreceptor of the present invention.
FIG. 2 is a diagram showing a schematic configuration of an electrophotographic apparatus having a trig.

FIG. 2 is a diagram showing an example of a block of a facsimile having the electrophotographic photosensitive member of the present invention.

[Explanation of symbols]

1 Electrophotographic photoreceptor of the present invention 2 axes 3 Primary charging means 4 Image exposure light 5 Developing means 6 Transfer means 7 Transfer material 8 Image fixing means 9 Cleaning means 10 Pre-exposure light 11 Process Cartridge 12 rails 13 Image reading section 14 Controller 15 Receiver circuit 16 Transmitter circuit 17 telephone 18 lines 19 Image memory 20 CPU 21 Printer Controller 22 Printer

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-64-75525 (JP, A) JP-A-8-225639 (JP, A) JP-A-8-146640 (JP, A) JP-A-8- 95264 (JP, A) JP 7-181706 (JP, A) JP 7-92701 (JP, A) JP 7-76619 (JP, A) JP 5-188628 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 5/00 CA (STN) REGISTRY (STN)

Claims (5)

(57) [Claims] 1. An electrophotographic photoreceptor having a photosensitive layer on a conductive support, the photosensitive layer comprising a charge generating layer and a charge transport layer.
Electrophotographic photosensitive having a transport layer, and the charge transport layer is a surface layer
In the polymer, the surface layer is a polymer having a constitutional unit represented by the following general formula (1), a general formula (1): [In the formula, A is —CR ₃ R ₄ — (provided that R ₃ and R ₄ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms), and 5 to 5 carbon atoms which may be substituted. 11-1,1-
A cycloalkyl group, an α, ω-alkylene group having 2 to 10 carbon atoms, a single bond, —O—, —S—, wherein R ₁ and R ₂ are a hydrogen atom, a halogen atom, or an optionally substituted alkyl group Represents an optionally substituted aryl group. ] And a copolymer in which one or more kinds of the structural unit represented by the general formula (1) is branched by an ester bond is contained, and at the end of the copolymer, all hydrogen atoms are substituted with fluorine atoms. An electrophotographic photoreceptor having a phenyl group. 2. The ester bond part in the general formula (1) has a structural unit represented by the following general formula (2).
The electrophotographic photosensitive member described. General formula (2) 3. The viscosity average molecular weight of the branched copolymer is 15,000 or less, and the content is 0.01% by weight or more and 30% by weight or less based on all resin components contained in the surface layer. The electrophotographic photosensitive member according to claim 1. 4. An electrophotographic photosensitive member according to claim 1, and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means, which are integrally supported and detachably mountable to the main body of the electrophotographic apparatus. A process cartridge characterized by the following. 5. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging unit, an image exposing unit, a developing unit, and a transferring unit.