JPH1080656A - Perpendicular coating applicator for cylindrical body and coating application method as well as manufacture of electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the formation of a smooth coating film at a high speed by providing the device with a coating liquid supplying mechanism and a coating liquid holding member having a circular aperture and moving a cylindrical body inserted into this aperture perpendicularly downward, thereby applying a coating liquid on the outer peripheral surface of this cylindrical body. SOLUTION: At the time of operating the coating applicator, the coating liquid 3 is supplied from a coating liquid supply port 61 and is primarily stored in a coating liquid reservoir 62; thereafter, the coating liquid is made to flow over from a weir 63 and is supplied to the coating liquid holding member 2. On the other hand, the cylindrical body 1 is moved perpendicularly downward relative to the coating liquid holding member 2 by ascending of a pedestal 5 or descending of the cylindrical body 1. At this time, the coating liquid flows between the coating liquid holding member 2 and the cylindrical body 1 and the coating liquid holding member 2 is moved in the radial direction of the cylindrical body 1 by the liquid pressure distribution by the nonuniformity of the gap between a coating liquid scraping section 21 and the coating liquid and, therefore, the coating liquid holding member 2 moves in such a manner that the center of this coating scraping section 21 and the center of the cylindrical body 1 are approximately aligned. The distribution of the gap is thus eliminated and the uniform coating film is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical coating apparatus for forming a coating film on an outer peripheral surface of a cylindrical body by passing a cylindrical body such as used for an electrophotographic photosensitive drum through a coating liquid, and a vertical coating apparatus therefor. It is about the method.

[0002]

2. Description of the Related Art A dip coating method and a vertical coating method are conventionally known as methods for coating a cylindrical body. The dip coating method has the advantage that the operation is simple, but it is necessary to dipped the cylinder slowly to stabilize the liquid level at the top of the dip tank and stabilize the flow of the coating liquid inside the dip tank. In order to prevent the coating liquid from being applied to the inside of the cylinder other than the surface to be coated,
It is necessary to have a mechanism to keep the inside of the cylinder airtight, and even if the inside of the cylinder is kept airtight, it is inevitable that the coating liquid adheres to a part of the inside of the cylinder. Is necessary, because the film thickness depends on the viscosity and the coating speed, strict viscosity control is required for controlling the film thickness, the coating speed is extremely slow, and the productivity is poor. Has a drawback such that a large amount of coating liquid is required.

On the other hand, in the conventional vertical coating method, a ring-shaped coating liquid container for holding a ring-shaped liquid leakage preventing elastic packing having an opening is provided, and a cylindrical body is provided in the opening of the elastic packing. Is inserted, and the cylindrical body is moved relatively vertically upward with respect to the ring-shaped coating liquid container, whereby the outer peripheral surface of the cylindrical body is applied. The production speed is somewhat faster, the step of removing the coating liquid adhering to the inner surface of the cylinder is unnecessary, the coating can be performed with a small amount of coating liquid, and the cylindrical body is continuously coated with a ring. By supplying the liquid to the liquid container, there is an advantage that continuous application becomes possible.

[0004]

However, even in such a vertical coating method, as in the dip coating method, since the film thickness depends on the viscosity and the coating speed, strict viscosity control is required for adjusting the film thickness. In addition, the problem that the coating speed is very slow and the productivity is poor cannot be solved.

[0005] In order to solve such a problem,
JP-A-56-15865, JP-A-56-1586
No. 6 discloses a vertical coating method using a coating apparatus having a ring-shaped coating material scraping blade (blade) on an upper portion of a coating container. In such a so-called blade coating method, the wet film thickness is determined by the gap between the substrate to be coated and the blade, and does not depend much on the properties of the coating liquid or operating conditions, and enables high-speed coating. However, in order to obtain a uniform film thickness, it is essential to control the gap between the substrate to be coated and the blade. In the methods disclosed in JP-A-56-15865 and JP-A-56-15866, a blade is movably held in a radial direction with respect to a cylindrical body for the purpose of controlling this gap, and the gap is controlled during coating. The so-called self-aligning mechanism is adopted, which keeps the gap constant by using the stress when the lifted coating liquid passes through the gap by rotating the cylindrical body and pulling it up relative to the coating container at the same time. I have.

However, in such a vertical coating method, since the coating liquid holding container and the coating liquid scraping member are integrated, the automatic alignment mechanism does not work effectively when the alignment is performed only by the liquid pressure. In addition, there are problems such as that the film thickness unevenness may be remarkable and that a relatively large reservoir for the coating liquid is required because the cylindrical body moves relatively upward with respect to the coating liquid holding container.

The present invention has been made to improve the above-mentioned drawbacks in the prior art. That is, an object of the present invention is to provide a miniaturized vertical coating apparatus and a coating method capable of forming a smooth coating film with small thickness unevenness at high speed by effectively performing automatic alignment. It is in. Another object of the present invention is to provide a coating apparatus for producing an electrophotographic photoreceptor and a method for manufacturing an electrophotographic photoreceptor using the vertical direction coating apparatus and the coating method.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to insert a cylindrical body into a horizontally movable coating holding member having an opening, and insert the cylindrical body into the coating liquid holding member. On the other hand, when moving relatively vertically downward, the cylindrical body is a part of the coating liquid holding member provided movably in the radial direction of the cylindrical body, slightly smaller than the outer diameter of the cylindrical body. The center of the scraping portion having a large inner diameter portion and the center of the cylindrical body are moved substantially without contact with the scraping portion while being centered by the weight and the liquid pressure of the coating liquid so that the center of the cylindrical body is substantially equal to the center of the cylindrical body. This is achieved by applying a coating liquid to the outer peripheral surface of the substrate.

That is, the coating apparatus of the present invention has a coating liquid supply mechanism and a coating liquid holding member having a circular opening. A cylindrical body is inserted into the opening, and the cylindrical body is inserted into the coating liquid holding member. By moving the coating liquid relatively vertically downward, the coating liquid is applied to the outer peripheral surface of the cylindrical body, and the coating liquid holding member is held movably in the radial direction of the cylindrical body,
Further, the circular opening is formed of a coating liquid scraping part.

Further, according to the coating method of the present invention, a coating liquid is supplied to a coating liquid holding member having a circular opening, a cylinder is inserted into the circular opening, and the cylinder is moved relative to the coating liquid holding member. The coating liquid is applied to the outer peripheral surface of the cylindrical body by moving the coating liquid vertically downward, and the coating liquid holding member is provided movably in the radial direction of the cylinder to form a circular opening. In the coating liquid scraping section, a cylindrical body having an outer diameter slightly smaller than the inner diameter of the coating liquid scraping section is inserted so that the center of the coating liquid scraping section is substantially equal to the center of the cylindrical body. The cylinder is moved without contacting the scraping portion while the coating liquid holding member is aligned by the action of the weight and liquid pressure of the coating liquid.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The coating apparatus of the present invention includes a coating unit for coating a coating liquid, a coating unit supporting device that supports the coating liquid movably up and down, and a substrate supporting device that supports a substrate. FIGS. 1 to 4 are used to explain them. FIG. 1 is a cross-sectional view of a coating unit forming a main part of a coating apparatus of the present invention, and FIG. 2 is a plan view thereof. FIG. 3 is a schematic configuration diagram of the coating unit support device, and FIG. 4 is a schematic configuration diagram showing a partial cross section of the coating object support device for supporting and rotating the coating object.

1 and 2, reference numeral 1 denotes a cylindrical body as an object to be coated, 2 denotes a coating liquid holding member, 21 denotes a cylindrical coating liquid scraping section, 3 denotes a coating liquid, and 4 denotes a coating liquid holding member (a scraping section). 41, a coating liquid holding member holding portion, 5 a pedestal, 6 a coating liquid supply mechanism, 61 a coating liquid supply port, 62 a coating liquid reservoir, 63
Denotes a weir for adjusting the amount of coating liquid, and 64 denotes a lid for preventing solvent volatilization. In FIG. 3, reference numeral 101 denotes a base,
102 is a motor, 103 is a ball screw, 104 is a guide, and 105 is a lift. In FIG. 4, 1 is a cylindrical body, 201 is a supporting member, 202 is an AC servomotor, 203 is a pulley, 204 is a rotary joint,
05 is a pulley, 206 is a belt, 207 is a rotating member, 2
08 is a supporting member, and 209 is a rotating member.

In the coating apparatus of the present invention, the coating unit shown in FIG. 1 is supported by the coating unit supporting device shown in FIG. That is, the lift 105 is attached to the ball screw 103 provided on the base 101, and the coating unit shown in FIG. 1 is placed on the lift. The lift table can be moved up and down along a pair of guides 104 by rotating a ball screw 103 by a motor 102. On the other hand, although not shown in FIG.
An object-to-be-coated support device is provided separately, and a cylinder as an object to be coated is arranged so as to pass through an opening provided at the center of a coating unit placed on the elevating table.
Therefore, when the elevator 102 is moved upward by driving the motor 102, the coating liquid is applied to the periphery of the cylindrical body by the coating unit mounted thereon.

FIG. 4 shows an example of a device for supporting an object to be coated.
The support device is provided with a mechanism for rotating a cylindrical body as an object to be coated. In this support device, the upper rotating member 209 is supported by the supporting member 201 via a bearing, and the lower rotating member is supported by the supporting member 208 via a bearing. Further, the lower rotating member 207 is configured to rotate by driving the AC servomotor 202. That is,
The rotation of the AC servomotor 202 is transmitted to a rotating member by a pulley 203 mounted on a motor, a pulley 205 mounted on a rotary joint, and a belt 206 suspended therebetween. Therefore, the cylindrical body 1 can be rotated by mounting the cylindrical body 1 between the rotating members 209 and 207 of this support device and driving the AC servomotor 202.

Next, the coating unit in the coating apparatus of the present invention will be described. The pedestal 5 includes a coating liquid holding member 2,
A centering mechanism 4 and a coating liquid supply mechanism 6 are provided to constitute a coating unit. The coating liquid holding member 2 has a flange portion 22 at an upper portion and a cylindrical coating liquid scraping portion 21 at a lower portion, and is held movably in the radial direction of the cylindrical body 1. The alignment mechanism 4 of the coating liquid holding member will be described. The upper flange portion 22 of the coating liquid holding member 2 is provided with the concave portion provided in the coating liquid holding member holding portion 41 in the alignment mechanism 4 and the coating liquid supply mechanism 6. The coating liquid holding member 2 is slidably sandwiched between the bottom surface and the bottom surface so that the coating liquid holding member 2 can move in the radial direction of the cylindrical body by an amount corresponding to the gap a. It is preferable that the dimension b of the concave portion sandwiching the coating liquid holding member 2 is set to be slightly larger than the thickness of the coating liquid holding member and equal to or less than the thickness of the coating liquid holding member + 0.2 mm.

The pedestal 5 of the coating unit shown in FIGS. 1 and 2 is placed on the lifting table 105 of the coating unit supporting device. The coating liquid 3 is supplied from a coating liquid supply port 61 as shown by a black arrow, and a coating liquid reservoir 62 is provided.
After the primary storage, the water flows over the weir 63 and overflows inward, flows along the inclined surface of the weir 63, and is uniformly supplied to the coating liquid holding member 2. On the other hand, the cylinder 1, which is the object to be coated, moves vertically downward relative to the coating liquid holding member 2 by raising the pedestal 5 or lowering the cylinder 1 (in FIG. 3, the pedestal 5 rises). Let it. Thereby, the coating liquid 3 held by the coating liquid holding member 2 is applied to the surface of the cylindrical body.
That is, the coating liquid 3 flows between the coating liquid holding member 2 and the cylindrical body 1 due to the relative movement of the cylindrical body 1, but at this time, the gap between the cylindrical coating liquid scraping portion 21 and the cylindrical body 1 is not sufficient. The coating liquid holding member 2 is moved in the radial direction of the cylindrical body by the liquid pressure distribution caused by the uniformity, so that the center of the coating liquid scraping portion and the center of the cylindrical body are substantially equal. Moves, and the distribution of the gap is eliminated, so that a uniform coating film can be obtained.

The relative moving speed of the cylindrical body 1 with respect to the coating liquid holding member 2 is desirably 1 cm / sec or more in order to apply a shear stress effective for alignment to the coating liquid 3. In addition, the movement speed is desirably 2 m / sec or less due to an increase in machine vibration at higher speeds.

The cylindrical body 1 may be rotated with respect to the coating liquid holding member 2 to facilitate alignment. In this case, the following two methods can be considered. That is,
(1) a method of stopping after rotating the cylindrical body 1 and immediately moving the cylindrical body 1 downward with respect to the coating liquid holding member 2;
(2) There are two methods of rotating the cylinder 1 during the relative movement of the cylinder 1. In the case of (1), since the scraping portion 21 of the coating liquid holding member 2 is already centered as compared with the case where it is not rotated, a smooth coating film can be obtained immediately after the start of coating. In this case, the rotation speed is 50 rpm to 500 rpm.
m is more preferable, and more preferably 50 rpm to 300
rpm range. In the case of (2), the relative rotational speed of the cylindrical body 1 is determined by the relative moving speed of the cylindrical body 1, and is preferably 5 rpm to 500 rpm in order to suppress the occurrence of a spiral surface failure. More preferably, it is in the range of 10 rpm to 300 rpm.

The coating liquid scraping portion 21 of the coating liquid holding member 2
A cylindrical shape having a cylindrical surface parallel to the surface of the cylindrical body 1 as shown in FIG. 1 is desirable. Further, the coating liquid holding member 2 is used to effectively hold and flow the coating liquid, as shown in FIG.
The shape may have a tapered structure as shown in FIG.

The material constituting the coating liquid holding member 2 includes
Metals, resins, ceramics, glass, and the like are used. In particular, it is desirable to use a rigid body that is excellent in workability and easily provides high processing accuracy, for example, a metal such as stainless steel or aluminum. Further, in order to smoothly perform the alignment, the coating liquid holding member 2 is preferably subjected to Teflon treatment by anodic oxidation or electroless plating.

As the material of the coating liquid holding member holding portion 41, a material having good processing accuracy and a small surface friction coefficient is preferable. For example, stainless steel or aluminum subjected to Teflon treatment by anodic oxidation or electroless plating is used. Such metals are available.

The coating liquid supply mechanism 6 is preferably provided with a solvent volatilization preventing lid 64 in order to minimize solvent evaporation in the coating liquid 3. The coating liquid supply mechanism 6 is not limited to the one shown in FIG.
Any structure may be used as long as it is a mechanism that uniformly supplies in the circumferential direction.

The coating liquid 3 is made of a known resin depending on the purpose of coating.
Although a mixture of a pigment, a solvent, and the like is appropriately selected, a known coating solution for forming a photosensitive layer used for an electrophotographic photosensitive member may be used. At that time, the viscosity of the coating liquid was 0.5 Pa. s
The above is preferable, and more preferably, 1 Pa. s to 5 Pa. s range. Examples of the solvent include alcohols such as methanol, ethanol, isopropanol, and butanol; aliphatic hydrocarbons such as hexane, octane, and cyclohexane; aromatic hydrocarbons such as benzene, toluene, and xylene; dichloromethane, dichloroethane, and carbon tetrachloride. , Halogenated hydrocarbons such as chlorobenzene, dimethyl ether, diethyl ether, tetrahydrofuran, ethers such as ethylene glycol, acetone, ketones such as methyl ethyl ketone, ethyl acetate, esters such as methyl acetate, dimethyl formaldehyde, dimethyl formamide, dimethyl sulfoxide, Water and the like.

The material of the cylindrical body 1 to be coated includes metals such as stainless steel, aluminum and nickel, polyethylene, polypropylene, Teflon and ABS.
Although resin, glass, paper tube and the like are used, any material may be used as long as it is a rigid body having good shape accuracy. The cylindrical body 1 has an outer diameter slightly smaller than the inner diameter of the coating liquid scraping section. The difference between the inner diameter of the coating liquid scraping section and the outer diameter of the cylindrical body is 0.1 to It is preferably in the range of 2 μm.

[0025]

EXAMPLES In order to further clarify the effects of the present invention, specific examples will be described below. Example 1 As a cylinder 1 to be coated, 30 mmφ × 340 m
The coating was performed using an aluminum pipe having a length of m and a coating apparatus constituted by the apparatus shown in FIGS. The interval “b” in the coating liquid holding member centering mechanism 4 is 0.1 mm larger than that of the coating liquid holding member 2.
Increased by 1 mm. The coating and holding member 2 is made of aluminum having a surface treated with polytetrafluoroethylene and has an inner diameter of 30.3 mmφ and a height of 30.3 mmφ to 40 mm.
A cylindrical shape having a taper structure of 60 mm and a coating liquid scraping portion 21 having a surface parallel to one surface of a cylindrical body having a height of 6 mm was used. As the coating liquid 3, a solution prepared by dissolving 100 parts by weight of polycarbonate (trade name: Iupilon Z, Z-200, manufactured by Mitsubishi Gas Chemical Company) in 300 parts by weight of monochlorobenzene (Kanto Chemical, special grade) was used. The viscosity of the coating liquid 3 at a liquid temperature of 25 ° C. is about 3.5 Pa.
s.

First, as shown in FIG. 1, the cylinder 1 was moved downward relative to the coating liquid holding member 2 and inserted into the coating liquid holding member 2. Next, the coating liquid 3 was fed using the coating liquid supply mechanism 6 so as not to overflow the tapered portion of the coating liquid holding member 2, and the outer surface of the cylindrical body 1 was immersed in the coating liquid 3. From this state, the cylindrical body 1 is moved downward by 20 relative to the ring-shaped coating liquid container 2.
It was moved at a speed of cm / sec. As a result, a uniform coating film could be formed on the outer peripheral surface of the cylindrical body 1 without any visual surface defects. The film thickness distribution of the coating film applied to the outer peripheral surface of the cylindrical body 1 was measured with a β-ray film thickness meter (Fischer). Table 1 shows the results. The ratio of the standard deviation to the average of all the film thickness data in the table (hereinafter, this characteristic value is referred to as film thickness unevenness) is about 8.2%, indicating a fairly uniform film thickness distribution.

[0027]

[Table 1] Average film thickness: 19.686 μm Standard deviation: 1.61352 μm Film thickness unevenness = (standard deviation) / (average film thickness): 8.1965
%

Example 2 After the cylindrical body was rotated at 300 rpm, the rotation was stopped, and immediately thereafter, the coating was performed under the same conditions as in Example 1. As a result, a uniform coating film was formed on the outer peripheral surface of the cylindrical body without any visual surface defects. Table 2 shows the film thickness distribution of the coating film applied to the outer peripheral surface of the cylindrical body. The film thickness unevenness shows a very uniform film thickness distribution at about 4.7%.

[0029]

[Table 2] Average thickness: 19.457 μm Standard deviation: 0.91778 μm Thickness unevenness = (standard deviation) / (average thickness): 4.7171
%

Example 3 Coating was performed under the same conditions as in Example 1 except that the cylinder was rotated at 100 rpm. As a result, a uniform coating film was formed on the outer peripheral surface of the cylindrical body without any visual surface defects. Table 3 shows the thickness distribution of the coating film applied to the outer peripheral surface of the cylindrical body. The film thickness unevenness shows a very uniform film thickness distribution at about 3.3%.

[0031]

[Table 3] Average film thickness: 20.444 μm Standard deviation: 0.68161 μm Film thickness unevenness = (standard deviation) / (average film thickness): 3.3341
%

Example 4 18 parts by weight of polycarbonate (trade name: Iupilon Z, Z-200, manufactured by Mitsubishi Gas Chemical Company) and a charge transport agent (N, N'-diphenyl-N, N'-bis ( 3-
Coating was performed under the same conditions as in Example 2 except that a solution in which 12 parts by weight of (methylphenyl) -4,4'-diamine) was dissolved in 70 parts by weight of monochlorobenzene (manufactured by Kanto Chemical Co., Ltd., special grade) was used. At this time, the viscosity of the coating liquid 31 at a liquid temperature of 25 ° C. is about 1.0 Pa. s. As a result, a uniform coating film was formed on the outer peripheral surface of the cylindrical body without any visual surface defects. Table 4 shows the film thickness distribution of the coating film applied to the outer peripheral surface of the cylindrical body 1. The film thickness unevenness shows a fairly uniform film thickness distribution at about 2.6%.

[0033]

[Table 4] Average film thickness: 24.578 μm Standard deviation: 0.65023 μm Film thickness unevenness = (standard deviation) / (average film thickness): 2.6455
5%

[0034]

According to the coating apparatus of the present invention having the above-described configuration, the coating unit can be reduced in size.
By using this coating apparatus, it becomes possible to form a smooth coating film with a small thickness unevenness on the outer peripheral surface of a cylindrical body which is an object to be coated at a high speed using a small amount of a coating liquid. Therefore, the coating apparatus of the present invention is suitable for producing an electrophotographic photosensitive member.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a coating unit as a main part of a coating apparatus according to the present invention, illustrating a state in which a cylindrical body is coated.

FIG. 2 is a plan view of the coating unit of FIG.

FIG. 3 is a schematic configuration diagram of a coating unit support device in the coating device of the present invention.

FIG. 4 is a schematic configuration diagram showing a partial cross section of a device for supporting an object to be coated in the coating device of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... cylindrical body, 2 ... coating liquid holding member, 21 ... coating liquid scraping part, 22 ... flange part, 3 ... coating liquid, 4 ... alignment mechanism, 41
... Coating liquid holding member holding section, 5 ... Pedestal, 6 ... Coating liquid supply mechanism,
61 ... Coating liquid supply port, 62 ... Coating liquid reservoir, 63 ... Weir, 64 ...
Solvent volatilization prevention lid, 101: base, 102: motor,
103: ball screw, 104: guide, 105: lifting platform, 201: support member, 202: AC servomotor,
203: pulley, 204: rotary joint, 205
... pulley, 206 ... belt, 207 ... rotating member, 208
...... Support member, 209 ... Rotating member.

Claims (14)

[Claims] 1. A coating liquid supply mechanism and a coating liquid holding member having a circular opening, a cylindrical body is inserted into the opening, and the cylindrical body is positioned vertically downward relative to the coating liquid holding member. In the coating apparatus for applying the coating liquid to the outer peripheral surface of the cylindrical body by moving the coating liquid, the coating liquid holding member is held so as to be movable in the radial direction of the cylindrical body, and the circular opening is scraped with the coating liquid. A coating device comprising: 2. The coating apparatus according to claim 1, wherein a coating liquid supply mechanism for supplying a coating liquid to the coating liquid holding member is provided above the coating liquid holding member. 3. The coating apparatus according to claim 1, wherein the coating liquid holding member has a tapered portion for feeding the coating liquid. 4. The coating apparatus according to claim 1, wherein the coating liquid holding member is made of a rigid body. 5. The coating apparatus according to claim 1, wherein the coating liquid holding member has a surface that has been subjected to a treatment for improving slip. 6. The coating apparatus according to claim 1, wherein the coating liquid scraping section has a cylindrical surface. 7. The coating apparatus according to claim 1, further comprising a rotating device for rotating the cylindrical body. 8. A coating liquid is supplied to a coating liquid holding member having a circular opening, a cylinder is inserted into the circular opening, and the cylinder is moved vertically downward relative to the coating liquid holding member. Thereby, in the coating method for applying the coating liquid to the outer peripheral surface of the cylindrical body, the coating liquid holding member is provided so as to be movable in the radial direction of the cylindrical body, the coating liquid scraping portion forming a circular opening thereof, A cylinder having an outer diameter slightly smaller than the inner diameter of the coating liquid scraping section is inserted, and the weight and liquid of the coating liquid are adjusted so that the center of the coating liquid scraping section and the center of the cylinder are substantially equal. A coating method, wherein the cylindrical body is moved without contacting the scraping portion while the coating liquid holding member is aligned by the action of pressure. 9. The coating method according to claim 8, wherein a relative moving speed between the cylindrical body and the coating liquid holding member is 1 cm / sec or more. 10. The method according to claim 1, wherein the cylinder is moved at 50 rpm before moving.
The coating method according to claim 8, wherein the rotation is performed at 500 rpm, and after the rotation is stopped, the coating is moved relatively vertically downward. 11. The method according to claim 1, wherein the cylinder is moved from 5 rpm to 5 rpm while moving.
9. The coating method according to claim 8, wherein the rotation is performed at 00 rpm. 12. The coating liquid having a viscosity of 0.5 Pa.s. 9. The coating method according to claim 8, wherein the number is at least s. 13. A coating liquid supply mechanism and a coating liquid holding member having a circular opening, a cylindrical body is inserted into the circular opening, and the cylindrical body is placed vertically downward relative to the coating liquid holding member. By moving, in an electrophotographic photoreceptor manufacturing coating apparatus that applies a photoreceptor forming coating liquid to the outer peripheral surface of the cylindrical body, the coating liquid holding member is held movably in the radial direction of the cylindrical body, and A coating device for producing an electrophotographic photosensitive member, wherein the circular opening comprises a coating liquid scraping portion. 14. A coating liquid for forming a photosensitive layer is supplied to a coating liquid holding member having a circular opening, a cylinder is inserted into the circular opening, and the cylinder is vertically positioned relative to the coating liquid holding member. In a coating method of applying a coating solution for forming a photosensitive layer to the outer peripheral surface of a cylindrical body by moving the coating liquid holding member downward, the coating liquid holding member is provided so as to be movable in a radial direction of the cylindrical body, and a circular opening is formed. A cylindrical body having an outer diameter slightly smaller than the inner diameter of the coating liquid scraping section is inserted into the coating liquid scraping section so that the center of the coating liquid scraping section is substantially equal to the center of the cylindrical body. An electrophotographic photoreceptor which moves the cylindrical body without contacting the scraping portion while aligning the coating liquid holding member by the action of the weight and liquid pressure of the coating liquid for forming the photosensitive layer. Method of manufacturing.