JP2882593B2 - Electrophotographic photoreceptor - 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, and more particularly to a highly durable electrophotographic photoreceptor having a high surface hardness and excellent abrasion resistance, which enhances the quality and reliability of the photoreceptor. The present invention also relates to an electrophotographic photoreceptor capable of reducing running cost by further improving durability.

[0002]

2. Description of the Related Art An electrophotographic photosensitive member is a main medium for forming an image in an electrophotographic process such as a copying machine or a laser beam printer. The image forming process includes charging,
It consists of repeated processes of exposure, development, transfer, cleaning, and static elimination. More specifically, when an electrophotographic photosensitive member uniformly charged by a corona electrode or a rubber electrode is exposed to a light image using halogen light or laser light, the charged potential of the exposed portion is attenuated, and an electrostatic latent image is formed. You. Next, the electrostatic latent image is developed using a developer called toner composed of charged fine particles, and a visible image is formed on the electrophotographic photosensitive member. The visible image is transferred to the transfer material by the Coulomb force and the pressure by the transfer charging. At this time, all the toner is not transferred,
Since the toner remains on the electrophotographic photosensitive member, it is necessary to clean the residual toner in order to use the toner repeatedly. After cleaning, the charge history is removed by strong exposure, bias application, or the like, and then the process proceeds to the next repetitive process.

[0003] The cleaning will be described in more detail. Fur brushes, magnetic brushes, blade cleaning and the like are known as means for removing fine particles such as toner. In particular, blade cleaning is the most frequently used cleaning method because of its high cleaning accuracy and simple device configuration. As shown in FIGS. 1 and 2, the blade cleaning has a structure in which a blade 1 of an elastic member made of a plate-like polyurethane or the like is attached to a support 2, and is pressed and contacted in the direction of the generatrix of the photoreceptor. It is configured to be. As shown in FIG. 2, the direction in which the blade abuts is divided into a forward direction and a counter direction as shown in FIG. From the viewpoint of cleaning accuracy, the latter counter-type cleaning is more preferable. Further, in order to improve the cleaning accuracy, it is preferable to increase the contact pressure of the blade 1 with the photoconductor 3.

[0004]

The improvement of the cleaning accuracy as described above is very important for maintaining the image quality at the time of repeated use, while increasing the frictional force generated between the photosensitive member and the blade. Has the disadvantage that The increase in the frictional force between the two significantly reduces the life of the photoreceptor due to an increase in the amount of scraping of the photoreceptor and the occurrence of scratches.

In particular, in recent years, organic photoreceptors whose use has rapidly increased due to their advantages such as mass productivity, low cost and low pollution have no sufficient mechanical strength on the surface and extremely poor durability. Was something. The biggest reason is that in the organic photoreceptor, the organic binder forming the photosensitive layer does not have sufficient mechanical strength. That is, since the organic photoconductive compound having photoreceptor properties hardly has sufficient film forming properties by itself, it is necessary to use the organic photoconductive compound in a form compatible with or dispersed in an organic binder to form a film as a photoreceptor. there were. Particularly, the loss of photoreceptor characteristics is small in a solvent-soluble thermoplastic binder, but none of such binders has excellent mechanical strength.

On the other hand, attempts have been made to obtain a high-hardness photosensitive layer after a polymerization process using a polymerizable monomer or oligomer. Specifically, JP-A-55-85058,
Nos. 61-41152, 61-201461, 62-201460, JP-A-1-
Nos. 116553, 1-134364 and 1-134365.

[0007] However, the compatibility and dispersibility of monomers and oligomers, and furthermore, their polymerization products and photoconductive compounds are not good. In addition, the photoconductive compound was often deteriorated during the polymerization reaction, and the photoconductor characteristics were not satisfied.

[0008] The present invention provides an organic photoreceptor using an organic photoconductive compound, which forms a high hardness surface by polymerizing a specific polysynthetic monomer, and has high durability and excellent scratch resistance and abrasion resistance. An object is to provide an electrophotographic photosensitive member.

[0009]

In the electrophotographic photoreceptor of the present invention, the surface layer located on the outermost surface thereof has the following general formula:

[0010]

Embedded image (Where R "indicates a = CH _2, R 'is an alkyl chain, O, CO, 1 kind selected from NH and S, R"-R'-CR is selected from H, CH ₃ and phenyl group And a monomer polymer represented by the following formula:

In the present invention, Rs may be the same or different. Specific examples thereof include groups or atomic groups having a structure as shown in Table 1 below.

The above-mentioned monomers are polymerized by radical polymerization, and have a very high functional group density.
Since the reaction rate is extremely fast, the polymerization reaction proceeds even under mild conditions, and therefore, the photoconductive material is hardly damaged. Further, it has excellent compatibility and dispersibility with the photoconductive material. Furthermore, due to the extremely high functional group density, the polymer has a very high hardness.

In the present invention, in order to polymerize the above monomer, an initiator which generates a radical is used. There are two cases for this, thermal radicals and photo radicals. Examples of the thermal polymerization initiator that generates a radical by heat include a peroxide, an azo compound, a tetraalkylthiuram disulfide, and an organometallic compound. These can be used alone, but when two or more kinds are used in combination, the polymerization reaction can be more efficiently advanced in some cases. It is also possible to promote the generation of radicals by combining with a reducing agent. Examples of such a reducing agent include ferrous salts, tertiary amines, naphthenates, mercaptans, and organometallic compounds. Can be

Tables 2 and 3 below show specific examples of the thermal polymerization initiator.

As the photopolymerization initiator, acetophenone,
Examples include benzoin, benzophenone, thioxanthone, anthraquinone, benzyl, camphorquinone, and Michler's ketone. These generate radicals by light in the ultraviolet region, but they can generate radicals more effectively when used in combination with a photoinitiating auxiliary such as amine, sulfone, or phosphasis. Since the photopolymerization initiators have different absorption wavelengths, the use of two or more photopolymerization initiators can improve the radical generation efficiency. Further, by using in combination with a photosensitizer having absorption in the visible region, radicals can be generated by visible light.

The following Tables 4 to 12 show examples of typical photopolymerization initiators, photoinitiating assistants and photosensitizers.

The most suitable light source for generating photoradicals is selected depending on the type of photoinitiator or photosensitizer. A high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, an electrodeless lamp, a xenon lamp, Excimer laser, He-Cd laser and the like are used.

Radiation is generated even in a yarn not containing an initiator by electron beam irradiation, so that a polymerization reaction can be carried out. Either a scanning type or a non-scanning type can be used for electron beam irradiation.

The monomer used in the present invention can be polymerized after mixing with other polymerizable monomers and oligomers, and further with other polymer binders. Mixable polymer binders (including those obtained by polymerizing thermoplastic resins and the above-mentioned polymerizable monomers and oligomers) include polyester, polyurethane, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, polyamideimide , Phenolic resin, acrylic resin, silicone resin, epoxy resin, urea resin, allyl resin, alkyd resin, melamine resin, nylon, polysulfone, polyallyl ether, polyacetal, butyral resin,
Fluororesin and the like. In particular, acrylate, methacrylate, and epoxy-based polymerizable monomers and oligomers have excellent compatibility and are convenient for forming a mixed system.

Next, the layer constitution of the electrophotographic photosensitive member of the present invention will be described.

In the present invention, the photosensitive layer may have a single-layer structure or a laminated structure. In a single photosensitive layer, photocarriers are generated and moved between the same layers, and the photosensitive layer itself is the surface layer. On the other hand, the laminated photosensitive layer has a configuration in which a charge generation layer that generates photocarriers and a charge transfer layer in which the generated carriers move are stacked. The surface layer in the laminated photosensitive layer may be either the charge generation layer or the charge transport layer. In either case of a single layer or a laminate, a protective layer can be provided on the photosensitive layer. In this case, the protective layer is a surface layer. In any case, in the present invention, the surface layer contains a polymerization product of the monomer of the present invention, and forms a surface layer having high hardness and excellent wear resistance.

The single-layer photosensitive layer of the present invention preferably has a thickness of 8 to 40.
It is used in a thickness of μm, more preferably 12 to 30 μm. It preferably contains 20 to 80% of a photoconductive material such as a charge generation material and a charge transport material, and more preferably 3 to 80%.
0 to 70%.

In the laminated photosensitive layer of the present invention, the thickness of the charge generation layer is preferably from 0.001 μm to 6 μm, more preferably from 0.01 μm to 2 μm. The amount of the charge generation material contained in the charge generation layer is preferably from 10 to 100% by weight,
More preferably, it is 50 to 100%. The thickness of the charge transport layer is preferably from 5 to 70 μm, more preferably from 60 to 70 μm.
30 μm. The amount of the charge transporting material contained in the charge transporting layer is preferably 20 to 80% by weight, and more preferably 30 to 70%.

The charge generating materials used in the present invention include phthalocyanine pigments, polycyclic quinone pigments, trisazo pigments, disazo pigments, azo pigments, perylene pigments, indigo pigments, quinacridone pigments, azulhenium salt dyes, squalium dyes, cyanine dyes, Examples include a pyrylium dye, a thiopyrylium dye, a xanthene dye, a quinone imine dye, a triphenylmethane dye, a styryl dye, selenium, a selentellurium alloy, amorphous silicon, and cadmium sulfide.

Examples of charge transport materials include pyrene compounds, N-alkylcarbazole compounds, hydrazone compounds, N, N-dialkylaniline compounds, diphenylamine compounds, triphenylamine compounds, triphenylmethane compounds, pyrazoline compounds, styryl compounds, And stilbene compounds.

When a protective layer is provided, its thickness is 0.01 to 1
It is preferably 0 μm, more preferably 0.1 to 7 μm.
The protective layer may contain a charge generation material or a charge transport material. Further, the protective layer may contain a conductive material such as a metal and its oxide, nitride, salt, alloy, and carbon. Examples of such metal species include iron, copper, gold, silver, lead, zinc, nickel, tin, aluminum, titanium, antimony, indium, and the like. Specifically, ITO, Ti
O ₂ , ZnO, SnO ₂ , Al ₂ O _{3 and the} like can be used. The conductive material is dispersed in the form of fine particles in the protective layer, and the particle size is preferably 0.001 to 5 μm, more preferably 0.01 to 1 μm.
μm, and the amount added to the protective layer is preferably 1 to 70%, more preferably 5 to 50%.
As a dispersant, a titanium coupling agent, a silane coupling agent, various surfactants, and the like may be used.

When a layer other than the surface layer is formed, a polymerization product of a monomer is not always necessary, and a film is formed of the following polymer compound. That is, polyester, polyurethane, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, phenolic resin, acrylic resin, silicone resin, epoxy resin, urea resin, allyl resin, alkyd resin, polyamideimide, nylon, polysulfone, Polyallyl ether, polyacetal, butyral resin and the like.

The conductive substrate of the electrophotographic photoreceptor of the present invention comprises:
Metals and alloys such as iron, copper, gold, silver, aluminum, zinc, titanium, lead, nickel, tin, antimony, and indium, or oxides, carbon, and conductive polymers of the above metals can be used. The shapes include a drum shape such as a cylindrical shape and a column shape, and a belt shape and a sheet shape.
The conductive material may be formed as it is, used as a paint, deposited, or processed by etching or plasma processing. In the case of paints, paper, plastic, etc., as well as the above metals and alloys, are used as the base.

An undercoat layer may be provided between the conductive substrate and the photosensitive layer. The undercoat layer functions as a charge injection control at the interface and as an adhesive layer. The undercoat layer is mainly made of a binder resin, but may contain the above-mentioned metal or alloy, or an oxide, salt, or surfactant thereof. Specific examples of the binder resin forming the undercoat layer include polyester, polyurethane, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide,
Polypropylene, polyimide, phenolic resin, acrylic resin, silicone resin, epoxy resin, urea resin,
Allyl resin, alkyd resin, polyamide imide, nylon, polysulfone, polyallyl ether, polyacetal, butyral resin and the like can be mentioned. The thickness of the undercoat layer is preferably 0.05 μm to 7 μm, and more preferably 0.1 μm to 2 μm.

For the production of the electrophotographic photosensitive member of the present invention, methods such as vapor deposition and coating are used. The coating method can form films of various compositions in a wide range from a thin film to a thick film. Specifically, it is applied by a bar coder, knife coater, dip coating, spray coating, beam coating, electrostatic coating, roll coater, attritor, powder coating, or the like.

The electrophotographic photosensitive member of the present invention can be applied as a photosensitive member to all electrophotographic apparatuses including a copying machine and a laser beam printer. As an example, FIG.
FIG. 1 shows a schematic configuration example of a general transfer type electrophotographic apparatus using the electrophotographic photosensitive member of the present invention.

In the figure, reference numeral 100 denotes an electrophotographic photosensitive member of the present invention as an image carrier, which is driven to rotate around an axis 101a in a direction indicated by an arrow at a predetermined peripheral speed. The electrophotographic photoreceptor receives a uniform charge of a predetermined positive or negative potential on its peripheral surface by a charging means 102 in the course of its rotation, and then a photo 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.

This electrostatic latent image is then developed with toner by developing means 104, and this toner development is transferred between the photosensitive member 101 and the transfer means 105 from a paper feeding unit (not shown) by a transfer means.
The transfer material P is sequentially transferred onto the surface of the transferred transfer material P fed in synchronization with the rotation of one.

The transfer material P having undergone the image transfer is separated from the photoreceptor surface and introduced into the image fixing means 108, where the image is fixed, and then printed out as a copy.

The surface of the photoreceptor 101 after the image transfer is cleaned and cleaned by removing the untransferred toner by the cleaning means 106, and is further subjected to a static elimination treatment by the pre-exposure means 107, and thereafter is repeatedly used for image formation. You.

As the uniform charging means 102 for the photosensitive member 101, a corona charging device is generally widely used. Also, a corona charging device is generally widely used for the transfer device 105. 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 photoconductor 101 and the cleaning means 106 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. In this case, 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 may be reflected light or transmitted light from the original, or a laser beam based on a signal obtained by reading the original and forming a signal. Scanning, driving of an LED array, or driving of a liquid crystal shutter array.

When used as a facsimile printer, the light image exposure L is an exposure for printing received data. FIG. 5 is a block diagram showing an example of this case.

The controller 111 controls the image reading unit 110 and the printer 119. The entire controller 111 is a CPU 117
Is controlled by The read data from the image reading unit 110 is transmitted to the partner station through the superstition circuit 113. Data received from the partner station is sent to the printer 1
Sent to 19. The image memory 116 stores predetermined image data. The printer controller 118 is a printer 119
Is controlling. 114 is a telephone.

The image information received from the line 115 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 112, and then decoded by the CPU 117. Is stored. When the image information of at least one page is stored in the memory 116, the image of the page is recorded. The CPU 117 reads out one page of image information from the memory 116 and sends the decoded one page of image information to the printer controller 118. When receiving the image information of one page from the CPU 117, the printer controller 118 controls the printer to record the image information of the page.

The CPU 117 receives the image information of the next page during the recording by the printer 119.

As described above, image reception and recording are performed.

The electrophotographic photosensitive member of the present invention is used not only for an electrophotographic copying machine but also for a laser beam printer,
It can be widely used in electrophotographic applications such as CRT printers, LED printers, liquid crystal printers, and laser plate making machines.

[0044]

The present invention will be described below with reference to examples.

Example 1 Nylon (10 parts by weight of trade name "M-4000" manufactured by Toray Industries, 100 parts by weight of methanol and 90 parts by weight of isopropanol were mixed and dissolved, and then the outer diameter was 80 mm, the wall thickness was 1.5 mm, and the length was 3
Dip coating on 63mm aluminum cylinder, 9
After drying at 0 ° C. for 20 minutes, an undercoat layer of 2.0 μm was provided.

Next, 10 parts by weight of the following trisazo pigment:

[0047]

Embedded image (Where Ar is

[0048]

Embedded image X is Cl. ) Was dispersed in a sand mill to obtain a charge generation layer coating material. This paint was dip-coated on the undercoat layer,
After drying at 0 ° C. for 20 minutes, a charge generation layer of 0.15 μ was obtained.

Next, 20 parts by weight of the following biphenyl compound:

[0050]

Embedded image 5 parts by weight of the following monomer,

[0051]

Embedded image 0.15 parts by weight of the following initiator,

[0052]

Embedded image And polycarbonate resin (bisphenol A type: Mw 5
A solution obtained by mixing 15 parts by weight (0,000) and 300 parts by weight of monochlorobenzene was applied onto the charge generation layer by dip coating. 100
After drying at 5 ° C. for 5 minutes, ultraviolet light irradiation of 1200 μJ / cm ² was performed with a high-pressure mercury lamp, and immediately, drying was performed at 120 ° C. for 60 minutes to obtain a photoconductor having a 15 μm charge transport layer. Comparative Example 1 20 parts by weight of the biphenyl compound of Example 1 and a similar polycarbonate resin (bisphenol A type: Mw 50,000) 2
0 parts by weight and 300 parts by weight of monochlorobenzene were mixed.
This solution was applied onto the charge generating layer of Example 1 by dip coating,
Drying at 60 ° C. for 60 minutes gave a photoreceptor having a charge transport layer of 23 μm. Example 2 10 parts by weight and 0.4 part by weight of the monomer and the photoinitiator of Example 1 were mixed with 90 parts by weight of methyl ethyl ketone, and this solution was spray-coated on the charge transport layer of Comparative Example 1. Drying at 70 ° C. for 10 minutes, irradiation with 1200 μJ / cm ² of ultraviolet light, and drying at 120 ° C. for 60 minutes were successively performed to obtain a photoreceptor having a 1.2 μm protective layer. Comparative Example 2 A photoconductor having a protective layer was obtained in the same manner as in Example 2, except that the following monomers were used.

[0053]

Embedded image [Evaluation of physical properties] i) Abrasion test At the time of manufacturing the photoreceptor, a sample using an aluminum sheet having a thickness of 50 µ instead of the aluminum cylinder was also prepared. This sheet sample was subjected to an abrasion test with a weight of 500 g × 2 and 5,000 revolutions using a Taber abrasion tester, and the weight loss of the sample was measured. As a result, it was 9.6 mg in Comparative Example 1, but 0.28 mg in Example 1, showing good wear resistance. Further, in Comparative Example 2, the difference was 0.2 due to the difference in the type of the acrylate monomer.
In contrast to 43 mg, Example 2 using the monomer of the present invention showed an extremely good abrasion resistance of 0.05 mg. ii) Scratch test Using a Haydon scratch tester, the surface of the photoreceptor was scratched with a 0.5 mm diameter diamond needle under a load of 50 g, and the depth was measured. In Comparative Example 1, the scratch was 5.1 μm, in Example 1 was 0.5 μm, and in Comparative Example 2 was 0.6 μm, whereas in Example 2 was 0.2 μm. However, it was shown that the photoreceptor of the present invention had extremely high surface hardness. [Evaluation of actual machine] A copying machine manufactured by Canon (trade name “Color Laser Copier 200 (CLC-200)”) was used. 20,000 full-color copies were made on A4 size paper, and the photoreceptor shaving amount, the decrease in dark potential, and the background fog of a solid white image were tested.

The results are summarized in Table 1. The results show that the photoreceptor of the present invention is extremely excellent in durability since the shaving amount is small, and there is no reduction in dark potential and no fogging. Example 3 A sample was prepared and evaluated in the same manner as in Example 2 except that the following monomer and initiator were used.

Monomer

[0056]

Embedded image Initiator

[0057]

Embedded image Example 4 A similar sample was prepared in Example 2 except that the following monomers and initiator were used, and good results were obtained.

Monomer

[0059]

Embedded image Initiator

[0060]

Embedded image Example 5 After the charge transport layer of Comparative Example 1 was provided on the undercoating layer of Example 1, the charge generation layer of Example 1 was provided to obtain an inverse layer photoreceptor. The protective layer of Example 4 was provided thereon to obtain a photoreceptor. CLC-200
In the evaluation of, the high-voltage transformer was changed to reverse the polarity of the primary charging, the transfer charging, and the developing bias. Good results were obtained as in the other examples. Comparative Example 3 The photoconductor of Example 4 having no protective layer was designated as Comparative Example 3. Since this photoreceptor had a thin surface charge generation layer, it was evaluated with a CLC-200. As a result, the charge generation layer was scraped off with the durability of 100 sheets, and no image appeared. Examples 6 and 7 After mixing 10 parts by weight and 0.5 part by weight of the monomer and the initiator of Example 3 with 90 parts by weight of methyl ethyl ketone, Sn
3 parts by weight of O ₂ fine particles (average particle diameter: 0.05 μ) were added, and dispersion was performed at 3,300 rpm for 6 hours using a small sand mill using glass beads. The dispersion thus obtained was spray-coated on the charge transport layer of Comparative Example 1, dried at 75 ° C. for 15 minutes, irradiated with 1500 μJ / cm ² ultraviolet rays, dried at 120 ° C. for 60 minutes, and protected at 3.0 μ. A photoreceptor having a layer was obtained. This is Example 6. A photoconductor in which a similar protective layer was provided on the charge transport layer of Example 5 is referred to as Example 7. Example 6 used ordinary CLC-200, and Example 7 used CLC-200 in which the polarity of the high-voltage transformer used in Example 5 was changed. Both provided good results. Comparative Examples 4 and 5 The same samples were prepared and evaluated except that the monomers used in Comparative Example 2 were used instead of the monomers used in Examples 6 and 7. Compared with Examples 6 and 7, the photosensitive member was less susceptible to abrasion and scratching, and could not be said to be a practically usable photosensitive member. Example 8 10 parts by weight of the monomer of Example 1 and the photoinitiator of Example 1
A solution prepared by mixing 5 parts by weight, 250 parts by weight of methyl ethyl ketone and 250 parts by weight of isopropanol, and a solution prepared by mixing 40 parts by weight of thermoplastic modified polyethylene terephthalate (molecular weight: 20,000) and 500 parts by weight of hexafluoroisopropanol were prepared. After mixing the seed solutions, the mixture was spray-coated on the charge transport layer of Comparative Example 1. 60
℃, drying for 5 minutes, UV irradiation of 1500μJ / cm ² , 120 ℃, 6
After drying for 0 minutes, a photoreceptor having a 1.1 μm protective layer was obtained.

The details of the above results are summarized in Table 13 below.

[0062]

[Table 1]

[0063]

[Table 2]

[0064]

[Table 3]

[0065]

[Table 4]

[0066]

[Table 5]

[0067]

[Table 6]

[0068]

[Table 7]

[0069]

[Table 8]

[0070]

[Table 9]

[0071]

[Table 10]

[0072]

[Table 11]

[0073]

[Table 12]

[0074]

[Table 13]

[0075]

The photoreceptor cured by containing the monomer of the present invention in the surface layer can provide a highly durable photoreceptor having a high hardness surface layer and extremely excellent abrasion and scratch resistance.

[Brief description of the drawings]

1A is a plan view of a normal cleaning blade, FIG. 1A is a side view of the cleaning blade of FIG. 1A, FIG. 1B is a plan view of another normal cleaning blade, and FIG. The side view of the cleaning blade of (B).

FIG. 2 is an explanatory diagram showing an arrangement of a cleaning blade with respect to a photoconductor.

FIG. 3 is an explanatory diagram showing another arrangement of the cleaning blade with respect to the photoconductor.

FIG. 4 is a schematic configuration diagram of a general transfer type electrophotographic apparatus.

FIG. 5 is a block diagram of a facsimile using the electrophotographic apparatus of FIG. 4 as a printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blade 2 Support 3,101 Photoconductor 102 Charging means 103 Exposure section 104 Developing means 105 Transfer means 106 Cleaning means 107 Pre-exposure means 108 Image fixing means

Claims (1)

(57) [Claims] 1. An electrophotographic photoreceptor comprising a conductive substrate and a photosensitive layer provided thereon, wherein the surface layer located at the outermost surface of the photoreceptor has the following general formula: (Where R "indicates a = CH _2, R 'is an alkyl chain, O, CO, 1 kind selected from NH and S, R"-R'-CR is selected from H, CH ₃ and phenyl group An electrophotographic photoreceptor comprising a monomer polymer represented by the following formula: