JPH07134428A - Apparatus for production of electrophotographic receptor - Google Patents

Abstract

PURPOSE:To provide the apparatus for production of the electrophotographic receptor capable of preventing unequal coating and forming uniform coating films by a simple and easy mechanism. CONSTITUTION:This apparatus has a tank for housing a coating liquid for forming a photosensitive layer on the surface of a cylindrical conductive base material 1, a clamping mechanism 18 for clamping the inside wall of this conductive base material 1 by coming into tight contact therewith and a lifting machine for immersing the base material 1 held by this clamping mechanism 18 into the coating liquid, then pulling up the base material out of the coating liquid. The clamping mechanism 18 has a microhole 12 opening at all times. Gas 19 confined between the clamping mechanism 18 and the coating liquid within the base material 1 when the conductive base material 1 is immersed into the coating liquid communicates with the atmosphere outside the base material 1 only through the microhole 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor manufacturing apparatus, and more particularly to an improved apparatus for forming a photoreceptor layer on a cylindrical support according to a dip coating method.

[0002]

2. Description of the Related Art In recent years, the development of organic photoconductive materials for electrophotographic photoreceptors has progressed, and they have come to be used more than conventional inorganic photoconductive materials. Photoreceptors using organic materials have some problems in sensitivity, durability and environmental stability, but toxicity,
There are many advantages over inorganic materials in terms of cost, degree of freedom in material design, and the like.

Therefore, various sensitizing methods have been proposed from the enthusiastic examination of each company, and among them, a substance that generates a charge carrier when irradiated with light (hereinafter referred to as "charge generating substance").
(Hereinafter referred to as "charge transport layer") and a layer mainly composed of a substance (hereinafter referred to as "charge transport substance") that receives and transports charge carriers generated in the charge generation layer (hereinafter referred to as "charge transport layer"). A layered type photoconductor (hereinafter referred to as “layer”) (hereinafter referred to as “function-separated type photoconductor”) exhibits excellent sensitization properties, and thus occupies most of the organic photoconductor structure currently in practical use. Is coming. Further, it is expected as the mainstream of photoconductors in the future due to the improvement of durability in recent years.

Further, an undercoat layer is provided for the purpose of improving the charging property, preventing unnecessary injection of charges from the support, covering defects on the support, preventing pinholes, improving the adhesiveness of the photosensitive layer, and the like. As a result, durability is improving.

Examples of the coating method of the organic electrophotographic photosensitive member include a spray method, a bar coating method, a roll coating method, a blade method, a ring method and a dipping method. Especially the immersion method
This is a method of forming a photosensitive layer by immersing a conductive substrate in a coating tank filled with a photoreceptor coating solution and then pulling it up at a constant rate or a rate that changes sequentially. Because of its superiority, it is often used in the production of electrophotographic photoreceptors.

An example of an apparatus used for dip coating is shown in FIG. In the apparatus shown in the figure, a bath 4 contains a coating liquid 5 containing a photoconductor. A cylindrical conductive substrate 1 held by a chucking mechanism 8 in a coating liquid 5 in a tank 4
Is soaked. For immersion, the chucking device 8
The substrate 1 is lowered by the elevator 2 including the motor 3, and the base material 1 is dipped in the coating liquid 5. After sufficiently dipping, the chucking mechanism 8 is lifted by the elevator 2. The liquid overflowing from the tank 4 upon immersion is collected in the auxiliary tank 7 and returned to the tank 4 by the pump 6.

When the photosensitive layer is formed on the cylindrical conductive substrate by the dipping method, the coating is prevented from being applied to the portion (the inner surface of the substrate) and the gripping mechanism which do not need to be coated, and the loss of the coating liquid is reduced. Therefore, in order to reduce the cost, it is necessary to provide a chucking device having a mechanism for gripping the inside of the cylindrical conductive base material in a sealable manner. As a device for preventing such a coating liquid from entering the inside of the base material, a chucking device having an inflatable / contractible bag portion (Japanese Patent Laid-Open No. 59-44).
No. 66), a chucking device (see Japanese Patent Application Laid-Open No. 3-60766) having a mechanism for pressing the O-ring against the inner surface of the substrate has been proposed.

[0008]

When the chucking device disclosed in these publications is used, air is sealed in the conductive base material during coating. In such a closed type, the volume of the air sealed inside the base material increases due to the evaporation of the solvent of the coating liquid and the temperature difference between the coating liquid and the base material during the dip coating process, resulting in an opening at the bottom of the base material. Bubbles from the part,
There was a problem such as uneven application. In order to solve this problem, a chucking device having an air bleeding mechanism for an on-off valve (see Japanese Patent Application Laid-Open No. 59-4467) and a chucking device having a gas pressure adjusting chamber of variable volume (Japanese Patent Application Laid-Open No. 63-192046). For example, refer to the official gazette). However, in both cases, the mechanism is very complicated, and the problem that the control thereof requires high accuracy remains. Further, since the air bleeding mechanism is driven during the coating process, there is a problem that vibration is generated in the apparatus itself, which causes uneven coating.

An object of the present invention is to solve the above problems and to prevent uneven coating by a simple and easy mechanism.
An object of the present invention is to provide an electrophotographic photoreceptor manufacturing apparatus capable of forming a uniform coating film.

[0010]

In the present invention, an apparatus for producing an electrophotographic photosensitive member in which a photosensitive layer is formed on the outer surface of a cylindrical conductive substrate is used for forming the photosensitive layer. Of the coating liquid, a gripping mechanism that is in close contact with the inner wall of the conductive base material and grips the conductive base material, and the base material held by the gripping mechanism is immersed in the coating liquid in the bath and then the coating liquid. And a moving mechanism for moving the base material in the height direction of the cylinder relative to the tank in order to lift the base material from above. The gripping mechanism has micropores that are always open, and when the conductive base material is immersed in the coating liquid, the gas trapped between the gripping mechanism and the coating liquid inside the base material is a micropore. And communicates with the atmosphere outside the substrate.

In the above apparatus, when the conductive substrate is immersed in the coating solution, the flow rate of gas leaking through the micropores is 0.01 to 10 Nl / mi at a pressure of 1 kgf / cm ² .
It is preferably n. Further, the minimum cross-sectional area of the micropores is preferably 0.001 to 0.5 mm ² .

Further, in the present invention, an apparatus for producing an electrophotographic photosensitive member in which a photosensitive layer is formed on the outer surface of a cylindrical conductive substrate contains a coating solution for forming the photosensitive layer. The bath, the gripping mechanism that adheres to the inner wall of the conductive base material and grips it, and the conductive base material held by the gripping mechanism is immersed in the coating liquid in the bath and then pulled up from the coating liquid. Therefore, a moving mechanism that moves the base material in the height direction of the cylinder relative to the tank is provided, and when the conductive base material is immersed in the coating liquid, a gripping mechanism inside the base material. A gas can be trapped between the coating liquid and the coating liquid, and the gripping mechanism has a mechanism for moving the member in and out of the base material while keeping the airtightness, whereby the volume of the trapped gas is reduced. Adjusted.

Further, in the present invention, an apparatus for producing an electrophotographic photosensitive member having a photosensitive layer formed on the outer surface of a cylindrical conductive substrate contains a coating solution for forming the photosensitive layer. The tank to be held, the gripping mechanism that adheres to the inner wall of the conductive base material and grips it, and the conductive base material held by the gripping mechanism is immersed in the coating liquid in the tank and then pulled up from the coating liquid. A moving mechanism for moving the base material relative to the tank in the height direction of the cylinder, and a gripping mechanism inside the base material when the conductive base material is immersed in the coating liquid. A gas can be trapped between the coating liquid and the gripping mechanism is provided with a cooling means for cooling the trapped air.

[0014]

The mechanism of the present invention will be described below with reference to the drawings.

FIG. 2 shows an example of a device according to the present invention in which a microscopic hole is formed in the gripping mechanism. FIG. 2 shows a gripping mechanism which is a particularly important part of the present invention. The mechanism shown in this figure is used, for example, in a chucking mechanism of an apparatus as shown in FIG. 1 and constitutes an electrophotographic photosensitive member manufacturing apparatus.

In FIG. 2, the gripping mechanism 18 has a bag-shaped member 9, a pipe 10 connected to the bag-shaped member 9, and a support 58 for supporting the bag-shaped member. This mechanism is inserted inside the cylindrical conductive substrate 1 during chucking. Then, when gas is introduced from the pipe 10, the bag-shaped member 9 expands and comes into close contact with the inner wall of the substrate 1 to be gripped. At this time, there is no gap between the bag-shaped member 9 and the base material 1, and the gas inside the base material 1 does not flow from between them.

On the other hand, in the gripping mechanism 18, the support 58
A micro hole 12 penetrating this mechanism is formed in.
The micropores 12 always remain open. Therefore, even if the bag-shaped member and the base material are brought into close contact with each other by chucking, the air 19 trapped inside the base material 1 is connected to the atmosphere outside the gripping mechanism 18 through the minute holes 12.

When the base material held by this mechanism is immersed in the coating liquid in the apparatus as shown in FIG. 1, the base material 1
The gas trapped between the gripping mechanism and the coating solution inside can gradually go out through the micropores 12 even if expanded under various conditions described above. Thereby, even if the volume of gas inside the base material increases, it is possible to prevent bubbles from being jetted from the opening at the lower end of the base material, and to prevent application unevenness due to bubbles. In addition, such a mechanism,
It has a very simple structure as compared with the conventional one using an air bleeding valve and a variable volume mechanism, and does not generate the vibration that has occurred due to conventional air bleeding.

In such a mechanism, the minimum sectional area of the micropores is preferably 0.001 to 0.5 mm ² . The flow rate of gas (air) leaking through the micropores is 1 kg pressure.
It is preferably about 0.01 to 10 Nl / min at f / cm ² . If both the minimum cross-sectional area and the flow rate are below the lower limits, the effect of air bleeding will decrease. Further, when the upper limit is exceeded, the flow of the coating liquid into the base material increases,
The coating on the inner wall of the substrate becomes remarkable, which requires cleaning work and causes loss of the coating liquid.

In the present invention, the micro holes are realized by providing various holes in the gripping mechanism.
It can be obtained by providing a needle, a capillary or the like, or by performing various etchings on a metal plate or the like to form fine holes.

FIG. 3 shows an example of an apparatus according to the present invention provided with a member for adjusting the volume of gas trapped in the base material. This figure also shows the gripping mechanism, and the mechanism shown in the figure is used for the chucking mechanism of the apparatus shown in FIG. 1 and constitutes an electrophotographic photosensitive member manufacturing apparatus.

In FIG. 3, the gripping mechanism 28 has a cylindrical member 20 and an O-ring 11 provided along the outer circumference thereof. In this mechanism, when chucking, the cylindrical member 20 is inserted into the inside of the base material 1, and the inner wall of the base material and the cylindrical member 2 are inserted.
The space between 0 and 0 is sealed by an O-ring 11. Therefore, when the base material 1 is gripped, gas does not flow between the cylindrical member 20 and the base material 1, and chucking is performed in a sealed state.

On the other hand, the cylindrical member 20 is provided with a rod-shaped rigid body 13, and the rigid body 13 extends into the grasped base material 1. A stretchable bag-shaped member 14 is provided at a portion where the rigid body 13 extends into the base material 1. This member 1
The numeral 4 seals a rigid body in the base material 1, and even if the rigid body is moved as described later, the air inside the base material 1 does not leak out through the rigid body portion. Also, the rigid body 13
The dust generated by the movement of the member 14 is prevented from entering the inside of the base material by the member 14.

In such a mechanism, the rigid body 13 can be put in and taken out. By this loading and unloading, the volume below the gripping mechanism is changed inside the base material. That is, when the base material is immersed in the coating liquid as described above, the volume of the air trapped between the coating liquid and the gripping mechanism is changed by taking in and out the rigid body. By this volume adjustment, even if the above-described expansion of the gas occurs, the pressure can be changed to prevent the generation of bubbles.

The change in volume due to the movement of the rod-shaped rigid body is easy to control. Further, in the case of such a mechanism, even if the sealing property of the variable volume portion is broken, it does not seriously affect the uniformity of the coating film and the coating liquid.

FIG. 4 shows an example of an apparatus in which the gripping mechanism is provided with cooling means in the present invention. This drawing also shows the gripping mechanism, and the mechanism shown in the drawing is used as a chucking mechanism of the apparatus shown in FIG. 1 and constitutes an electrophotographic photosensitive member manufacturing apparatus.

Referring to FIG. 4, the gripping mechanism 38 includes a cylindrical member 20 and an O-ring 11 provided along the outer circumference thereof.
Have. In this mechanism, when chucking, the cylindrical member 20 is inserted into the inside of the base material 1, and an O-ring 11 seals between the inner wall of the base material and the cylindrical member 20. Therefore, when the base material 1 is gripped, the cylindrical member 20 and the base material 1 are
The gas does not flow from between and, and chucking is performed in a sealed state.

On the other hand, the cylindrical member 20 is provided with a cooling member 15 at substantially the center thereof. The cooling member 15 is arranged inside the base material 1 when the mechanism grips the base material 1.

As the cooling member, various heat exchange devices can be used, but among them, it is preferable to use a thermoelectric cooling element utilizing the Peltier effect which can be electrically cooled. The cooling temperature and the efficiency are 5 ° C to 3 ° C while the cylindrical conductive substrate is immersed in the coating liquid.
It is preferable that the gas contained in the substrate can be cooled at about 0 ° C. At this time, a water droplet receiving member may be provided below the cooling member in order to prevent water droplets from mixing into the coating liquid due to condensation of the cooling member.

In chucking, the gas trapped between the coating liquid and the gripping mechanism is cooled by the cooling member 15, and its pressure is reduced. This prevents the ejection of bubbles from the opening at the lower end of the substrate. Such a mechanism is simple and it is easy to ensure the hermeticity. Further, since no drive source is used, there is no fear of vibration.

In the present invention, as the cylindrical conductive base material, a base material itself having conductivity such as aluminum, aluminum alloy, copper, zinc, stainless steel, nickel, titanium, etc. can be used. It is possible to use a plastic or paper obtained by vapor-depositing or coating aluminum, an aluminum alloy, indium oxide, tin oxide, or the like, a plastic or paper containing conductive particles, a plastic having a conductive polymer, or the like.

In forming the photosensitive layer, the conductive substrate is covered with scratches and irregularities, and the charging property is prevented from deteriorating during repeated use.
Due to the improvement of charging characteristics in low temperature / low humidity environment,
An undercoat layer may be provided between the conductive substrate and the charge generation layer / charge transport layer.

As the material for the undercoat layer, conventionally, polyamide, copolymer nylon, polyvinyl alcohol, polyurethane, polyester, epoxy, phenol resin,
Casein, cellulose, gelatin and the like are known, and particularly alcohol-soluble copolymer nylon is often used. These are water and various organic solvents, especially water, methanol, ethanol, butanol alone solvent, or water / alcohol, a mixed solvent of two or more alcohols, or dichloroethane, chloroform, trichloroethane, trichloroethylene, perchlorethylene, etc. It is dissolved in a mixed solvent of a chlorine-based solvent and alcohol and applied on the surface of the conductive substrate. In addition, if necessary, zinc oxide, titanium oxide, zinc oxide, titanium oxide, etc. may be used for the reason of setting the volume resistivity of the undercoat layer and improving the repeated aging characteristics under low temperature / low humidity environment.
It is known to disperse and contain inorganic pigments such as tin oxide, indium oxide, silica and antimony oxide.

These are dispersed / dissolved in the above-mentioned various organic solvents and dip-coated on a conductive substrate so that the film thickness is about 0.1 to 5 μm.

The charge generating layer contains a charge generating material which generates charges upon irradiation with light as a main component, and optionally contains a known binder, plasticizer and sensitizer. As the charge generating material, perylene imide, perylene pigments with perylene anhydride, quinacridone, polycyclic quinone pigments such as anthraquinone, metal and metal-free phthalocyanines, phthalocyanine pigments such as halogenated metal-free phthalocyanines, squarylium dyes, Azurenium dye, thiapyrylium dye, and azo pigment having a carbazole skeleton, styrylstilbene skeleton, triphenylamine skeleton, dibenzothiophene skeleton, oxadiazole skeleton, fluorenone skeleton, bisstilbene skeleton, distyryloxadiazole skeleton or distyrylcarbazole skeleton And so on.

As a method for forming the charge generating layer, there are a method of directly forming a film of a compound by vacuum vapor deposition and a method of dispersing and coating the compound in a binder resin solution to form a film, but the latter method is generally preferable, The film thickness of the generation layer is 0.05 to 5 μm, preferably 0.1 to 1 μm. In the case of preparation by coating, the method of mixing and dispersing the charge generating material in the binder resin solution and the coating method are the same as those for the undercoat layer. Examples of the binder resin for the binder resin solution include melamine resin, epoxy resin, silicone resin, polyurethane resin, acrylic resin, vinyl chloride-vinyl acetate copolymer resin, polycarbonate resin, and phenoxy resin. As a solvent for dissolving these resins, ketones such as acetone, methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, ethers such as tetrahydrofuran and dioxane, aromatic hydrocarbons such as benzene, toluene and xylene. , N, N
-Aprotic polar solvents such as dimethylformamide and dimethylsulfoxide can be used.

Examples of the charge transport material of the charge transport layer provided on the charge generation layer include hydrazone compounds, pyrazoline compounds, triphenylamine compounds, triphenylmethane compounds, stilbene compounds, oxadiazole compounds. Etc. can be used, and the charge transport layer coating solution is prepared by dissolving the charge transport substance in the binder resin solution. As the coating method of the charge transport layer, the same method as that of the undercoat layer is used.

The photosensitive layer of the electrophotographic photoreceptor contains one or more electron-accepting substances or dyes for the purpose of improving sensitivity and suppressing an increase in residual potential and fatigue during repeated use. May be included. Examples of the electron acceptor used here include succinic anhydride, maleic anhydride,
Acid anhydrides such as phthalic anhydride and 4-chloronaphthalic anhydride, cyano compounds such as tetracyanoethylene and terephthalmalondinitrile, aldehydes such as 4-nitrobenzaldehyde, anthraquinones such as anthraquinone and 1-nitroanthraquinone, 2 Polycyclic or heterocyclic nitro compounds such as 4,4,7-trinitrofluorenone and 2,4,5,7-tetranitrofluorenone can be used as the chemical sensitizer.

As the dye, for example, an organic photoconductive compound such as xanthene dye, thiazine dye, triphenylmethane dye, quinoline dye, copper phthalocyanine can be used as an optical sensitizer.

Further, the photosensitive layer may contain a well-known plasticizer in order to improve moldability, flexibility and mechanical strength. Examples of the plasticizer include dibasic acid ester, fatty acid ester, phosphoric acid ester, phosphoric acid ester, phthalic acid ester, chlorinated paraffin, and epoxy type plasticizer. Moreover, you may contain a leveling agent, antioxidant, a ultraviolet absorber, etc. as needed.

[0041]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. Example 1 A methoxymethylated nylon resin (Teijin Chemical Co., Ltd .: Resin Resin EF-30T) was added to an azeotropic composition mixed solvent of 28.7 parts by weight of methyl alcohol and 53.3 parts by weight of 1,2-dichloroethane.
0.9 parts by weight and non-conductive titanium oxide (Ishihara Sangyo: TTO
What was mixed with 17.1 parts by weight of -55A) was dispersed with a paint shaker for 8 hours to prepare a coating liquid for the undercoat layer. The coating liquid thus obtained is 1 mmt × 65 m
It was applied onto an aluminum drum base material of mφ × 348 mm.

For coating, coating was carried out by using the chucking mechanism shown in FIG. 2 in the apparatus shown in FIG. In the mechanism shown in FIG. 2, the micropore 12 has a minimum sectional area of 0.001 mm ² and a pressure of 1 kgf / cm ^2.
The flow rate of air in was 0.01 Nl / min.
As a result, an undercoat layer having a film thickness of 1.5 μm was obtained.

On top of that, 97 parts by weight of methyl isobutyl ketone, 1.5 parts by weight of a bisazo pigment of the structural formula [Chemical formula 1] [chloridane blue] and 1.5 parts by weight of butyral resin (manufactured by Union Carbide Co.). The mixed parts were dispersed with a paint shaker for 8 hours to prepare a charge generation layer coating liquid. The obtained coating liquid was coated with an apparatus using the gripping mechanism shown in FIG. 2 to obtain a charge generation layer having a film thickness of 0.8 μm. In the gripping mechanism, the minimum cross-sectional area of the micropores 12 was 0.01 mm ² , and the flow rate of air at a pressure of 1 kgf / cm ² was 0.5 Nl / min.

Further, 1 part by weight of a hydrazone compound [4,4-diethylaminobenzaldehyde-N, N-diphenylhydrazone] having the structural formula shown in [Chemical Formula 2] was added to 8 parts by weight of dichloromethane and a polycarbonate resin (Upilon manufactured by Mitsubishi Gas Chemical Co., Inc.). ) A mixture of 1 part by weight was stirred and dissolved with a magnetic stirrer to prepare a charge transport layer coating solution. The coating liquid thus obtained was further coated in the above apparatus to obtain a charge transport layer having a film thickness of 20 μm.
In the gripping mechanism, the minimum cross-sectional area of the micro holes 12 is 0.5 m
The flow rate of air at m ² and pressure of 1 kgf / cm ² is 10
It was set to Nl / min.

[0045]

[Chemical 1]

[0046]

[Chemical 2]

The electrophotographic photosensitive member thus obtained was very uniform and had a good coating layer.
The coating unevenness of each layer of the photoconductor and the length of the coated portion of the inner surface of the substrate were measured and shown in Table 1.

[0048]

[Table 1]

From these results, it was revealed that the coating area of the unnecessary portion was small and the loss of the coating liquid was very small. Further, when the image characteristics of the electrophotographic photosensitive member were evaluated by an actual copying machine (SF-2027 manufactured by Sharp Co., Ltd.), an extremely good image without image defects was obtained. Comparative Examples 1 and 2 An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the minimum cross-sectional area of micropores and the flow rate of air at the time of coating the charge transport layer in Example 1 were set as shown in Table 2, respectively. Was prepared and evaluated. The results are shown in Table 2.

In the electrophotographic photosensitive member of Comparative Example 1 using a gripping mechanism having no micropores, air bubbles were generated by the air blown out inside the base material during coating of the charge transport layer, resulting in a large amount of coating unevenness. Further, in the photoconductor of Comparative Example 2, a large amount of the coating liquid penetrated into the inside of the base material and was applied to the gripping member, resulting in a large loss of the coating liquid. In addition, cleaning work was also required due to the application of excess parts.

[0051]

[Table 2]

Embodiments 2 and 3 In Embodiment 1, the gripping mechanism shown in FIGS.
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the one shown in FIG. The results are shown in Table 3. In the table, the example shown in Example 2 uses the mechanism of FIG. 3, and the experiment shown in Example 3 uses the mechanism of FIG. The electrophotographic photosensitive member thus obtained showed extremely good characteristics in image evaluation by an actual copying machine.

[0053]

[Table 3]

[0054]

As described above, the apparatus for producing an electrophotographic photosensitive member according to the present invention is capable of producing an electrophotographic photosensitive member having a uniform coating film and showing extremely good image characteristics.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of an apparatus for performing dip coating for forming a photoreceptor layer.

FIG. 2 is a sectional view showing a specific example of the present invention.

FIG. 3 is a cross-sectional view showing another example of the present invention.

FIG. 4 is a sectional view showing another example of the present invention.

[Explanation of symbols]

 1 Cylindrical Conductive Substrate 2 Elevator 3 Motor 4 Tank 5 Coating Liquid 6 Pump 7 Auxiliary Tank 8 Chucking Mechanism 18, 28, 38 Gripping Mechanism 12 Micropore 13 Rigid Body 15 Cooling Means

Front page continued (72) Inventor Ryuhiro Morita 22-22 Nagaike-cho, Abeno-ku, Osaka, Osaka, Japan Sharp Co., Ltd. (72) Inventor Makoto Kurokawa 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture

Claims (5)

[Claims] 1. An apparatus for manufacturing an electrophotographic photosensitive member having a photosensitive layer formed on the outer surface of a cylindrical conductive base material, which contains a coating liquid for forming the photosensitive layer. And a holding mechanism that adheres to the inner wall of the conductive base material to hold the conductive base material, and the base material held by the holding mechanism is immersed in the coating solution in the tank and then pulled out from the coating solution. A moving mechanism that moves the base material in the height direction of the cylinder relative to the tank, the gripping mechanism has micropores that are always open, and the conductive base material is the coating material. When immersed in a liquid, the gas trapped between the gripping mechanism and the coating liquid inside the base material communicates with the atmosphere outside the base material only through the micropores. Equipment for manufacturing photographic photoreceptors. 2. When the conductive substrate is immersed in the coating solution, the flow rate of the gas leaking through the micropores is 1
The apparatus for producing an electrophotographic photosensitive member according to claim 1, wherein the value is 0.01 to 10 Nl / min in kgf / cm ² . 3. The minimum cross-sectional area of the micropores is 0.001 to
The apparatus for manufacturing an electrophotographic photosensitive member according to claim 1, wherein the size is 0.5 mm ² . 4. An apparatus for producing an electrophotographic photosensitive member having a photosensitive layer formed on the outer surface of a cylindrical conductive base material, which contains a coating liquid for forming the photosensitive layer. And a holding mechanism that adheres to the inner wall of the conductive base material to hold it, and the conductive base material held by the holding mechanism is immersed in the coating liquid in the bath and then from the coating liquid. To pull up
A moving mechanism that moves the base material in the height direction of the cylinder relative to the tank, and when the conductive base material is immersed in the coating liquid, the gripping inside the base material is performed. A gas can be confined between the mechanism and the coating liquid, and the gripping mechanism has a mechanism for moving the member in and out of the base material while keeping the airtightness. An apparatus for manufacturing an electrophotographic photosensitive member, characterized in that the volume of gas is adjusted. 5. An apparatus for manufacturing an electrophotographic photosensitive member, wherein a photosensitive layer is formed on the outer surface of a cylindrical conductive base material, containing an application liquid for forming the photosensitive layer. And a holding mechanism that adheres to the inner wall of the conductive base material to hold it, and the conductive base material held by the holding mechanism is immersed in the coating liquid in the bath and then from the coating liquid. To pull up
A moving mechanism that moves the base material in the height direction of the cylinder relative to the tank, and when the conductive base material is immersed in the coating liquid, the gripping inside the base material is performed. An apparatus for manufacturing an electrophotographic photosensitive member, characterized in that a gas can be trapped between a mechanism and the coating liquid, and that the gripping mechanism is provided with a cooling unit for cooling the trapped air. .