JPH04324454A - Electrophotographic sensitive body and production thereof - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body having excellent surface lubricity, wear resistance and durabili and maintaining high-grade image characteristics even after repeated use. CONSTITUTION:When an electrophotographic sensitive body with at least a photosensitive layer on an electric conductive substrate is produced, the outermost layer of the sensitive body is composed of at least two layers, that is, a layer rich in a resin binder and a layer rich in titanium oxide powder and the outermost layer is formed by separately spraying at least two kinds of coating materials, that is, a resin binder soln. and a dispersion of titanium oxide powder.

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 a method for manufacturing the same, and more particularly to an electrophotographic photoreceptor having excellent durability, potential stability, and surface slipperiness, and a method for manufacturing the same.

0002

[Field of Industrial Application] Electrophotographic photoreceptors undergo repeated steps of charging, exposure, development, transfer, cleaning, and charge removal in their image forming process. The electrostatic latent image formed by charging and exposure is developed with toner, which is fine powder. Further, the developed toner is transferred to a transfer material such as paper in a transfer process, but not 100% of the toner is transferred, but a portion remains on the photoreceptor. Unless this remaining toner is removed, high-quality images free of stains and the like cannot be obtained in repeated processes. Therefore, it is necessary to clean the remaining toner. Typical cleaning processes include those using fur brushes, magnetic brushes, blades, etc., but blade cleaning is generally selected from the viewpoints of cleaning accuracy and rationalization of the device configuration. To explain blade cleaning in more detail here, as shown in FIGS. 1(A) and 1(B), it has a configuration in which a plate-shaped elastic member made of a material such as polyurethane is pressed against and brought into contact with the photoreceptor to scrape off the remaining toner. It has become. In FIG. 1, 11 is a blade holding member, and 12 is a cleaning blade. In order to improve cleaning accuracy, it is necessary to appropriately increase the contact pressure of the blade against the photoreceptor. The blade 4 can be brought into contact with the photoreceptor 3 in a manner in which the blade is perpendicular to the photoreceptor, in a forward direction relative to the rotational direction as shown in FIG. 2, and in a reverse direction as shown in FIG. Although it is conceivable, from the viewpoint of cleaning accuracy, it is said that the type in the opposite direction as shown in FIG. 3 is preferable.

[0003] Such a structure for improving cleaning accuracy simultaneously increases the contact pressure between the photoreceptor and the blade, thereby increasing the frictional force generated between the two. the result,
Problems such as an increase in the amount of abrasion of the photoreceptor, the occurrence of scratches, and the so-called "blade turning" caused by the blade turning over result in poor cleaning and equipment stoppage. FIG. 4 shows a blade reversal condition that resulted in the device being stopped. It is known that lowering the coefficient of friction of the photoreceptor is effective in solving the problems related to cleaning as described above. Conventionally, a method of adding a lubricant to the surface layer of a photoreceptor has been proposed as a means of lowering the coefficient of friction of the photoreceptor. Specifically, JP-A-52-117134 and JP-A-53-1078
41, 54-26740, 54-27434, 5
4-86340, 54-143142, 54-14
3148, 56-9345, 56-126838,
57-14845, 57-74748, 57-3
5863, 57-76553, 58-44444,
58-70229, 58-102949, 58-
163958, 59-197042, 62-272
281, 63-30850, 63-56658, 63-58352, 63-58450, 63-61
255, 63-61256, 63-65449, 63-65450, 63-65451, 63-73
267, 63-221355, 63-249152
, No. 63-311356 and the like.

Titanium oxide (TiO2) is used as a lubricant.
) Powder is preferred.

[0005] Lubricants include acrylic resin, polycarbonate polystyrene resin, epoxy resin, polyester resin,
After being dispersed in a binder resin such as polyurethane resin, it is applied to the surface of a photoreceptor to form a film. The disadvantage of electrophotographic photoreceptors provided with a surface layer obtained by these methods is that when a large amount of lubricant is dispersed in order to satisfy the slipperiness required for the surface of the photoreceptor, this can lead to a decrease in sensitivity and residual potential. On the other hand, if the amount of lubricant added is decreased, the frictional resistance will increase, causing blade curling and the superiority of wear resistance will not be maintained.
Another problem is that it is difficult to achieve excellent performance in the three elements of electrophotographic properties. Therefore, in the lubricant-added photoreceptor surface layer, a sufficient amount of lubricant is added near the surface to satisfy the sliding properties, and slightly closer to the support to improve electrophotographic properties and wear resistance. It is necessary to satisfy the minimum amount of lubricant necessary to satisfy the properties, and the required properties differ in the thickness direction even within the same surface layer.

[0006] Accordingly, an object of the present invention is to provide an electrophotographic photoreceptor that satisfies each of surface slipperiness, abrasion resistance, and electrophotographic properties at a high level and maintains high-quality images even after repeated use. An object of the present invention is to provide an electrophotographic photoreceptor having an outermost layer containing a lubricant, and a method for manufacturing the same.

[0007]

[Means for Solving the Problems] According to the present invention, in an electrophotographic photoreceptor having at least a photosensitive layer on a conductive support, the outermost layer of the photoreceptor includes a layer rich in binder resin and a layer rich in titanium oxide powder. In an electrophotographic photoreceptor comprising at least two layers, and a method for producing an electrophotographic photoreceptor having at least a photosensitive layer on a conductive support, the outermost layer of the photoreceptor is coated with a binder resin solution. This method of manufacturing an electrophotographic photoreceptor is characterized in that the electrophotographic photoreceptor is formed by independently spraying at least two types of paints, ie, a titanium oxide powder dispersion and a titanium oxide powder dispersion.

The present invention will be further explained with reference to the drawings. (See Figure 5) 1 is a support body, which usually has a diameter of 24 mm to 240 mm.
It can be fixed to a jig and rotated at any number of rotations. Reference numerals 2 and 3 are paint atomization devices, and not only general air spray, but also airless spray and other atomization systems can be used. Furthermore, atomization devices 2 and 3
is a function of moving in a direction parallel to the center line of the support 1 at an arbitrary speed by a lifting device, and a distance from the support coating surface,
Equipped with adjustable angle function. The present invention is characterized in that the functions of the atomizing devices 2 and 3 are separated. That is, at the stage of forming the outermost layer (the most superficial layer of the photoreceptor) in the electrophotographic photoreceptor manufacturing process, paints with different functions are supplied to the atomizer 2 and the atomizer 3, respectively, and the paints are atomized to form a coating film. By mixing or finely separating paints that have multiple functions, a coating film with performance that cannot be obtained with an ordinary single paint is obtained.

More specifically, a case will be explained in which a binder resin solution is supplied to the atomizer 2 and a titanium oxide powder dispersion is supplied to the atomizer 3. As the binder resin of the binder resin solution, polycarbonate resin, acrylic resin, polyester resin, polyurethane resin, etc. are used after being dissolved in a normal organic solvent, and in some cases, a small amount of lubricant and photosensitive material may be added, and a sensitizer or antioxidant may be added. It is also possible to add additives such as.

[0010] The dispersion liquid consists of a lubricant and a solvent, but from the viewpoint of dispersion stability and performance, a binder resin or a dispersion aid may be added.
It is possible to add surfactants, photosensitive materials, and additives such as sensitizers and antioxidants. At least these two kinds of paints are atomized to form a coating film. In the present invention, it is possible to obtain various coating film characteristics by arranging the atomizers 2 and 3. If the support is rotated according to Figure 5 and the atomizer is moved from the top to the bottom to apply the coating, the area closest to the surface of the outermost layer will be covered with the binder resin (Figure 8(a)), and conversely, the atomizer will move from the bottom to the top. If it is applied in a uniform manner, the area near the surface becomes rich in titanium oxide (FIG. 8(b)). The degree of mixing or separation of at least two types of paint in these coating films can be arbitrarily adjusted by adjusting the arrangement of the atomizers 2 and 3, that is, the distance and angle between the atomizers 2 and 3. In Figure 6, the atomized paint remains completely mixed (Figure 8(c)), and in Figure 7, the atomized paint remains completely separated into a coating film. A fine laminated structure (FIG. 8(d)) is formed depending on the rotation speed of the support. Furthermore, although one set of each is shown in the figure, it is an effective means to use a plurality of atomization systems each consisting of atomization devices 2 or 3 depending on the required film quality and film thickness. FIG. 8(e) shows a preferred configuration of the outermost layer in the case where a protective layer with a thickness of 3.0 μm is provided as the outermost layer in the present invention. This preferred outermost layer structure is 0.5 μm from the surface of the photoconductor, which is the closest to the surface, in order to reduce excessive frictional force that occurs between the cleaning member and the photoconductor when the photoconductor is installed in an actual copying machine. A thin film region with a lubricant content of 30 to 50 wt% is provided in the thickness direction,
Furthermore, in order to satisfy electrophotographic properties such as sensitivity and residual potential, a layer containing a lubricant of 5 to 10 wt%, which is the minimum necessary for wear resistance, is formed continuously in the lower layer. The atomization system uses the configuration shown in FIG. 5. The binder resin solution is supplied to the atomization device 2, the lubricant dispersion liquid is supplied to the atomization device 3, and the pattern area of the paint atomized by the atomization devices 2 and 3 is 9.
Fixed in a 0% overlapping arrangement, and placed two supports above from the bottom in the figure.
Apply while rotating at 00 rpm to form a coating. For reference, the binder resin solution has a binder/photosensitive material/solvent ratio of 2/1/100 by weight, and the lubricant dispersion has a lubricant/binder/photosensitive material/surfactant/solvent ratio of 3/100 by weight. 3/1/0.1/150. Note that this is just one example, and the specific example of the surface layer is not limited to that shown in FIG. 8(e) depending on the required performance.

Next, the layer structure of the electrophotographic photoreceptor according to the present invention will be described. As the conductive support, metals and alloys such as iron, copper, gold, silver, aluminum, zinc, lead, tin, titanium, nickel, oxides of these metals, carbon, conductive polymer molded products, etc. are used. It is possible. In addition, we can apply conductive paint to non-conductive materials such as paper, plastic, and ceramics.
It may also be used after being subjected to conductive treatment such as vapor deposition. The shape may be a drum shape such as a cylinder or column, a sheet shape, or a belt shape. A conductive layer may be further provided between the support and the photosensitive layer, or an intermediate layer may be provided for the purpose of improving the adhesion and electrical properties between the photosensitive layer and the support or the conductive layer. The intermediate layer can be formed of casein, polyvinyl alcohol, nitrocellulose, polyvinyl butyral, polyester, polyurethane, gelatin, polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon), aluminum oxide, or the like. The thickness of the intermediate layer is suitably 0.1 to 10 μm, preferably 0.3 to 3.0 μm.

The present invention relates to a laminated photoreceptor in which a charge generation layer containing a charge generation substance and a charge transport layer containing a charge transport substance are laminated, and a single layer photoreceptor in which a charge generation substance and a charge transport substance are contained in a single layer. It can also be used for photoreceptors having a protective layer as the outermost layer among these laminated and single-layer photoreceptors. Examples of charge generating substances include phthalocyanine pigments, polycyclic quinone pigments, trisazo pigments, disazo pigments, azo pigments, perylene pigments, indigo pigments, quinacridone pigments, azulenium salt dyes, squalium dyes, cyanine dyes, pyrylium dyes, thiopyrylium dyes, and xanthene dyes. , triphenylmethane dye, styryl dye, selenium, selenium-tellurium alloy, amorphous silicon, cadmium sulfide, and the like. Pigments and dye-based charge-generating substances are generally used as paints by being dispersed in binder resins. Examples of such binder resins include polyvinyl butyral, polyvinyl benzal, polyarylate, polycarbonate, polyester, and polyester. , polyurethane, phenoxy resin, acrylic resin, cellulose resin, etc. are preferred.

Examples of charge transport substances include pyrene compounds, N-alkylcarbazole compounds, hydrazone compounds, N,N dialkylaniline compounds, diphenylamine compounds, triphenylamine compounds, triphenylmethane compounds, pyrazoline compounds, styryl compounds, and stilbenes. compounds, polynitro compounds, polycyano compounds, and the like. These charge transport substances are generally dissolved in a binder resin and used as a paint, but include polycarbonate, polyester, polyurethane, polysulfone, polyamide, polyarylate, polyacrylamide, polyvinyl butyral, phenoxy resin, acrylic resin, acrylonitrile. resin, methacrylic resin,
Examples include phenol resin, epoxy resin, alkyd resin, and the like. These charge-generating substances and charge-transporting substances may be used as a charge-generating layer and a charge-transporting layer in the form of a laminated photoreceptor, or they may be mixed to form a single-layer photoreceptor, and the present invention can be applied to the outermost layer. . The present invention can also be applied to cases where a protective layer or the like is provided as the outermost layer of a laminated or single-layer photoreceptor.

FIG. 9 shows a schematic configuration example of a general transfer type electrophotographic apparatus using the electrophotographic photoreceptor of the present invention.

In the figure, reference numeral 101 denotes a drum-type photoreceptor of the present invention as an image carrier, which is rotated at a predetermined circumferential speed in the direction of the arrow around a shaft 101a. The photoreceptor 101 is uniformly charged at a predetermined positive or negative potential on its circumferential surface by the charging means 102 during its rotation process, and then the photoreceptor 101 is charged uniformly at a predetermined positive or negative potential by the charging means 102.
At this point, a light image exposure L (slit exposure, laser beam scanning exposure, etc.) is applied by an image exposure means (not shown). As a result, electrostatic latent images corresponding to the exposed images are sequentially formed on the circumferential surface of the photoreceptor.

The electrostatic latent image is then developed with toner by a developing means 104, and the toner developed image is transferred by a transfer means 105 from a paper feeding section (not shown) between the photoreceptor 101 and the transfer means 105 as the photoreceptor 101 rotates. The images are sequentially transferred onto the surface of the transfer material P that is synchronously taken out and fed.

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

After the image has been transferred, the surface of the photoreceptor 101 is cleaned by cleaning means 106 to remove residual toner after transfer, and is further subjected to charge-eliminating treatment by pre-exposure means 107 and used repeatedly for image formation.

As the uniform charging means 102 for the photoreceptor 101, a corona charging device is generally widely used. Further, for the transfer device 105, corona transfer means is generally widely used. As an electrophotographic device, the above-mentioned photoreceptor, developing means,
A plurality of components such as the cleaning means may be integrally combined as an apparatus unit, and this unit may be configured to be detachable from the apparatus main body. For example, the photoreceptor 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 main body. At this time, the above-mentioned device unit may include a charging means and/or a developing means.

When the electrophotographic apparatus is used as a copying machine or a printer, the optical image exposure L converts reflected light or transmitted light from an original document, or reads the original into a signal, and uses this signal to scan a laser beam and control an LED array. This is done by driving a liquid crystal shutter array or by driving a liquid crystal shutter array.

When used as a facsimile printer, the optical image exposure L is exposure for printing received data. FIG. 10 is a block diagram showing an example of this case.

A controller 111 controls an image reading section 110 and a printer 119. The entire controller 111 is controlled by a CPU 117. Image reading section 1
The read data from 10 is transmitted to the other station through the transmission circuit 113. The data received from the other station is sent to receiving circuit 1.
12 to the printer 119. Image memory 116 stores predetermined image data. A printer controller 118 controls a printer 119. 114 is a telephone.

Image information received from the line 115 (image information from a remote terminal connected via the line) is
After being demodulated by the receiving circuit 112, the CPU 117 performs decoding processing, and the signals are sequentially stored in the image memory 116. Then, when at least one page of image information is stored in the memory 116, the image of that page is recorded. CPU1
17 reads one page of image information from the memory 116 and sends the decoded one page of image information to the printer controller 118. Printer controller 118
When receiving one page of image information from the CPU 117, it controls the printer 119 to record the image information of that page.

Note that the CPU 117 is receiving the next page while the printer 119 is recording.

[0025] Images are received and recorded in the manner described above.

The electrophotographic photoreceptor of the present invention can be used not only for electrophotographic copying machines, but also for laser beam printers, C
RT printer, LED printer, LCD printer,
It can also be widely used in electrophotographic applications such as laser engraving.

[0027]

EXAMPLES Next, the present invention will be explained in more detail using examples. Example 1 After mixing and dissolving 10 parts by weight of polyamide (CM-8000: manufactured by Toray), 100 parts by weight of methanol, and 80 parts by weight of butanol, an outer diameter of 80 mm, a wall thickness of 1.5 mm, and a length of 3
It was applied by dip coating onto a 63 mm aluminum cylinder, and after drying, an intermediate layer having a thickness of 1.0 μm was provided.

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

0
029]

embedded image 5 parts by weight of polyvinyl butyral resin (S-LEC BX-S, manufactured by Sekisui Chemical Co., Ltd.) and 600 parts by weight of cyclohexanone were dispersed in a sand mill device using glass beads to obtain a charge generation layer paint. This paint was applied onto the intermediate layer by a conventional spray coating method to obtain a charge generating layer having an adhesion amount of 150 mg/m 2 after drying.

Next, 10 parts by weight of a stilbene compound represented by the following structural formula,

[0031]

[Chemical formula 2] Polycarbonate resin (bisphenol Z type, product name:
A charge transport layer coating was prepared by dissolving 10 parts by weight of Iupilon Z200 (manufactured by Mitsubishi Gas Chemical Co., Ltd.) in 50 parts by weight of monochlorobenzene and 20 parts by weight of dichloromethane, which was applied by dip coating onto the charge generation layer, and after drying, a charge layer with a thickness of 20 μm was formed. A transport layer was provided.

Next, a protective layer was provided by the method shown below. 50 parts by weight of the above-mentioned stilbene compound and 75 parts by weight of the above-mentioned polycarbonate resin were mixed with 1 part by weight of monochlorobenzene.
Dissolved in 800 parts by weight to form a binder resin paint.
was supplied to the atomizing device 2 of the apparatus shown in FIG. Furthermore, 20 parts by weight of titanium oxide particles (SR-1T: manufactured by Sakai Chemical Co., Ltd.) were added to a solution consisting of 40 parts by weight of the aforementioned polycarbonate resin (Iupilon Z200) and 1000 parts by weight of monochlorobenzene, and a surfactant (GF-300: Toagosei Chemical)
1 part by weight was dispersed in a ball mill, and the resulting titanium oxide powder dispersion was supplied to the atomization device 3.

The support, on which the charge transport layer had been previously provided, was mounted on the apparatus shown in FIG. 5 and rotated at 200 rpm, and the atomizers 2 and 3 were simultaneously moved upward from the lower end of the support to form a coating film. . The atomizers 2 and 3 were arranged so that their paint atomization pattern areas overlapped by 90%. The thickness of the obtained protective layer was 3 μm. The photoreceptor thus obtained was designated as Example Photoreceptor 1.

Comparative Example 1 Comparative Photoreceptor 1 was a photoreceptor in which a protective layer was not provided in Example 1.

Comparative example 2 A photoreceptor similar to that of Example 1 was prepared up to the charge transport layer.

Next, 50 parts by weight of the same stilbene compound as in Example 1 and 75 parts by weight of the polycarbonate resin described above were dissolved in 1800 parts by weight of monochlorobenzene to obtain a binder resin paint, and titanium oxide particles (SR-
1T: manufactured by Sakai Chemical) was added to a solution consisting of 40 parts by weight of the aforementioned polycarbonate resin (Iupilon Z200) and 1000 parts by weight of monochlorobenzene, and 1 part by weight of a surfactant (GF-300: manufactured by Toagosei Chemical) was added. The resulting titanium oxide powder dispersion was mixed with a binder resin paint. This coating material was uniformly applied onto the charge transport layer prepared using the apparatus shown in FIG. 5 in the same manner as in Example 1, and after drying, a protective layer having a thickness of 3 μm was provided. The photoreceptor thus obtained was designated as Comparative Photoreceptor 2.

[Evaluation Results 1] Evaluation was performed using a Canon digital color copier (CLC-1). The evaluation results are shown in the table below, and the evaluation details are as follows. "Blade turning" occurs when the photosensitive drum is installed in a copying machine with a new cleaning blade (the cleaning blade is set in the counter direction (reverse direction) shown in Fig. 3) and the copying operation begins. Indicates that the cleaning blade has turned upside down and copying cannot continue. ``Durability'' shows the amount of wear on the photoconductor after 20,000 continuous color copies were made after the drum was attached with artificial toner application to avoid blade curling. ``Endurance image'' also indicates the image quality after 20,000 continuous color copies.

[0038]

[Table 1] Example 2 The same material as in Example 1 was prepared up to the charge generation layer.

Next, 70 parts by weight of the same stilbene compound as in Example 1 and 75 parts by weight of the polycarbonate resin also mentioned above were dissolved in 1500 parts by weight of monochlorobenzene to obtain a binder resin paint, and the atomizer of the apparatus shown in FIG. 2 was supplied. Furthermore, titanium oxide particles (SR-1T-5
20 parts by weight of the surfactant (GF-300) were added to a solution consisting of 40 parts by weight of the above-mentioned polycarbonate resin (Iupilon Z200), 20 parts by weight of the above-mentioned stilbene compound, and 1000 parts by weight of monochlorobenzene.
1 part by weight (manufactured by Toagosei Chemical Co., Ltd.) in a ball mill, and the resulting titanium oxide powder dispersion was supplied to the atomization device 3.

The support on which the charge generation layer had been provided was mounted on the apparatus shown in FIG. 5 and rotated at 200 rpm, and the atomizers 2 and 3 were simultaneously moved upward from the lower end of the support to form a coating film. . The paint atomization pattern areas of atomizers 2 and 3 are arranged so that they overlap by 90%, and the film thickness after drying of the coating film obtained by atomizer 2 is 15 μm, and the film thickness obtained by atomizer 3 is 5 μm. The discharge amount was adjusted so that The thickness of the surface layer obtained in this way after drying was 20 μm.
Met. This was designated as Practical Photoreceptor 2.

Comparative Example 3 A photoreceptor was prepared in the same manner as in Example 2 except that the outermost layer with a film thickness of 20 μm was formed after drying using only the atomizer 2 without operating the atomizer 3. It was set as body 3.

Comparative Example 4 A photoreceptor was prepared in the same manner as in Example 2 except that the coating direction was reversed, that is, the coating was applied below the upper end of the support, and this was designated as Comparative Photoreceptor 4.

[Evaluation Results 2] The evaluation method was the same as the method used to obtain Evaluation Results 1, and the results are summarized in the following table.

[0044]

[Table 2] Example 3 A material similar to Example 1 up to the intermediate layer was prepared. Next, 10 parts by weight of the stilbene compound shown in Example 1 and styrene-methyl methacrylate copolymer resin (trade name MS200) were added.
: Nippon Steel Chemical Co., Ltd.) was dissolved in 70 parts by weight of toluene to prepare a charge transport layer paint. This paint was applied onto the intermediate layer by dip coating, and after drying, a charge transport layer having a thickness of 15 μm was formed.

Next, disazo pigment 1 represented by the following structural formula
0 parts by weight

[0046]

A charge generation layer paint was prepared by dispersing [Chem. This paint was applied onto the charge transport layer using a conventional air spray device, and after drying, a charge generation layer having a thickness of 0.5 μm was provided.

Next, a protective layer was formed on the charge generation layer in exactly the same manner as the method for forming the protective layer shown in Example 1, and this electrophotographic photoreceptor was designated as Example Photoreceptor 3.

Comparative Example 5 Example 3 except that the protective layer was not provided in Example 3.
A photoreceptor completely similar to the above was prepared and designated as Comparative Photoreceptor 5.

Comparative Example 6 The same material as in Example 3 was prepared up to the charge generation layer.

Next, when forming a protective layer in Example 1, two pairs of the binder resin solution supplied to the atomizing device 2 and the titanium oxide powder dispersion liquid supplied to the atomizing device 3 shown in FIG. They were mixed uniformly at a ratio of 1:1, 1:1, and 1:2 to form a paint. This paint was supplied to an atomizer and a protective layer having a thickness of 3 μm after drying was provided on the charge generating layer. At this time, a photoreceptor with a protective layer obtained from a binder resin solution and a titanium oxide powder dispersion in a ratio of 2:1 was used as a comparison photoreceptor 6, and a photoreceptor similarly obtained from a 1:1 ratio was used as a comparison photoreceptor 7. A photoreceptor obtained in the same manner from 1:2 was designated as Comparative Photoreceptor 8.

[Evaluation Results 3] The experimental photoconductor 3 and comparative photoconductors 5, 6, 7, and 8 were used in a Canon plain paper copying machine NP-3.
It was attached to a modified 825 machine (primary charging was set to positive charging) and evaluated using the same method used to obtain evaluation result 1. However, the number of durable sheets was set at 50,000 sheets.

The evaluation results are shown below.

[0053]

[Table 3]

[0054]

[Table 4]

[0055]

As shown in the examples above, according to the present invention, while satisfying the electrophotographic properties required of a photoreceptor, remarkable improvements have been made in surface slipperiness and abrasion resistance, which were previously unobtainable. It has become possible to provide an electrophotographic photoreceptor that is highly durable and has high-quality image characteristics even after durability.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a blade.

FIG. 2 is a diagram showing a method (forward direction) of bringing the blade into contact with the photoreceptor.

FIG. 3 is a diagram showing a method of bringing the blade into contact with the photoreceptor (in the opposite direction).

FIG. 4 is a diagram showing an inverted state of the blade.

FIG. 5 is a diagram showing the state of paint spraying.

FIG. 6 is a diagram showing a state of paint spraying (for forming a completely mixed layer).

FIG. 7 is a diagram showing a state in which paint is sprayed (for forming a completely separated layer).

FIG. 8 is a configuration diagram of the outermost layer of the photoreceptor.

FIG. 9 is a schematic configuration diagram of a general transfer type electrophotographic apparatus.

FIG. 10 is a block diagram of a facsimile machine using an electrophotographic device as a printer.

[Explanation of symbols]

1 Support 2 Atomization device (for binder resin solution) 2'
Paint tank 3 Atomization device (for lubricant dispersion) 3'
Paint tank 4 Atomization device moving shaft 5 Support holding rotation device

Claims (15)

[Claims] Claim 1. An electrophotographic photoreceptor having at least a photosensitive layer on a conductive support, the outermost layer of the photoreceptor comprising:
An electrophotographic photoreceptor comprising at least two layers: a layer rich in binder resin and a layer rich in titanium oxide powder. 2. The electrophotographic photoreceptor according to claim 1, wherein the outermost layer of the photoreceptor is a charge transport layer. 3. The electrophotographic photoreceptor according to claim 1, wherein the outermost layer of the photoreceptor is a charge generation layer. 4. The electrophotographic photoreceptor according to claim 1, wherein the outermost layer of the photoreceptor is a protective layer. 5. The electrophotographic photoreceptor according to claim 4, wherein the photoreceptor has a charging characteristic of negative charge. 6. The electrophotographic photoreceptor according to claim 4, wherein the charging property of the photoreceptor is positive charging. 7. An electrophotographic apparatus comprising the electrophotographic photoreceptor according to claim 1. 8. A facsimile machine comprising the electrophotographic photoreceptor according to any one of claims 1 to 6, and receiving means for receiving image information from a remote terminal. 9. A method for producing an electrophotographic photoreceptor having at least a photosensitive layer on a conductive support, wherein the outermost layer of the photoreceptor is coated with at least two types of paints: a binder resin solution and a titanium oxide powder dispersion. A method for producing an electrophotographic photoreceptor, characterized in that the electrophotographic photoreceptors are formed by spraying each member independently. 10. The method for producing an electrophotographic photoreceptor according to claim 9, wherein the outermost layer of the photoreceptor is a charge transport layer. 11. The method for manufacturing an electrophotographic photoreceptor according to claim 9, wherein the outermost layer of the photoreceptor is a charge generation layer. 12. The method for producing an electrophotographic photoreceptor according to claim 9, wherein the outermost layer of the photoreceptor is a protective layer. 13. The method for manufacturing an electrophotographic photoreceptor according to claim 12, wherein the charging property of the photoreceptor is negative charging. 14. The method of manufacturing an electrophotographic photoreceptor according to claim 12, wherein the charging property of the photoreceptor is positive charging. 15. The method for producing an electrophotographic photoreceptor according to claim 9, wherein the binder resin solution and the titanium oxide powder dispersion are sprayed by a spray coating method.