JPH04298756A - Production of electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To form a uniform charge transfer coated film without generating brushing; etc., by forming a charge transfer layer by using a coating liquid for the charge transfer layer specified in a moisture content in environment specified in relative humidity. CONSTITUTION:The charge transfer layer is formed by using the coating liquid for the charge transfer layer which is prepd. by confining the moisture content to <=0.01wt.% in the environment of <=65% relative humidity. Derivatives of fluorene, fluorenone, etc., or >=2 kinds thereof are usable as the charge transfer material of this coating liquid. The above-mentioned coating liquid is prepd. by using a silicone resin, etc., as a binder, incorporating plasticizers, such as halogenated paraffin, and additives, such as ozone deterioration preventive agents of a phenol system and phosphorus system, and uniformly dissolving these materials into a solvent, such as acetone. The coating liquid is preferably processed by a molecular sieve having <=3A effective diameter of micropores. The temp. of the environment at the time of forming the charge transfer layer is preferably 16 to 25 deg.C.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electrophotographic photoreceptor.

0002

BACKGROUND OF THE INVENTION Electrophotographic photoreceptors using organic photoconductive compounds have recently been widely studied because they are advantageous in terms of flexibility, light weight, surface smoothness, cost, and the like. Among these, functionally separated electrophotographic photoreceptors, which are provided with a charge generation layer that generates charge carriers by light absorption and a charge transport layer that transports the generated charge carriers by an electric field, are conventionally known.
Rapid progress has been made in recent years because the sensitivity, which has been a major drawback of electrophotographic photoreceptors using organic photoconductive compounds, can be greatly improved.

These composite organic electrophotographic photoreceptors are used by being installed in electrophotographic devices (printers, copying machines, etc.) based on the Carlson method. However, in recent years, as the quality of printed images obtained with electrophotographic devices such as copiers and printers has increased, there has been an increasing demand for uniformity of the coating film on electrophotographic photoreceptors. In composite organic electrophotographic photoreceptors, the preparation method and coating method of the coating liquid for the charge transport layer, which requires a thick film, are key to making the coating film uniform. When forming a charge transport layer, a coating solution is prepared by dissolving a substance having a charge transport function, a binder, and additives as necessary in a solvent, and after being subjected to prescribed filtration, dip coating is performed. It is formed by applying a coating using a coating method such as a coating method, a spray coating method, a roll coating method, an applicator coating method, or a wire bar coating method, and then drying it.

Polycarbonate resin is generally used as the binder for the charge transport layer from the viewpoint of mechanical strength and transparency. Polycarbonate resins are known as bisphenol A type, bisphenol Z type, bisphenol F type and their derivatives depending on the structure, but from the viewpoint of solubility of the binder and the substance having charge transport function, methylene chloride, carbon tetrachloride, Solvents with relatively low boiling points and high evaporation rates are used, such as 1,2-dichloroethane, α-dichloroethane, methyl ethyl ketone, tetrahydrofuran, and dioxane.

[0005] Therefore, due to variations in the relative humidity in the coating environment of the coating solution for the charge transport layer, defects such as brushing occur, and a uniform charge transport layer cannot be formed, resulting in a decrease in image quality.

[0006]

[Problems to be Solved by the Invention] The present invention solves the above-mentioned problems of the prior art, and makes it possible to form a uniform charge transport layer coating without causing defects such as brushing (cloudiness, whitening). The purpose of the present invention is to provide a method for manufacturing an electrophotographic photoreceptor.

[0007]

[Means for Solving the Problems] The present invention provides a relative humidity of 65%.
The present invention relates to a method for producing an electrophotographic photoreceptor, characterized in that a charge transport layer is formed using a charge transport layer coating liquid having a water content of 0.01% by weight or less in an environment of 0.01% by weight or less.

In the present invention, the relative humidity of the environment when forming the charge transport layer must be 65% or less. It is preferably 30 to 60%, more preferably 35 to 55%, and particularly preferably 40 to 50%. If the relative humidity exceeds 65%, brushing will occur in the coating film, which is unsuitable. If it is too low, static electricity is likely to occur, which is inappropriate. The temperature of the above environment is 16~
The temperature is preferably 25°C, more preferably 18 to 23°C, and particularly preferably 20 to 22°C. If the environmental temperature is too low or too high, the solvent will volatilize unevenly and the leveling of the coating will tend to deteriorate.

[0009] In the present invention, the coating liquid for the charge transport layer is
It is necessary that the water content is 0.01% by weight or less. If the water content exceeds 0.01% by weight, a uniform charge transport layer coating cannot be obtained.

[0010] The coating solution for the charge transport layer can be treated, for example, with a molecular sieve whose micropores have an effective diameter of 3A or less to reduce the water content to 0.01% by weight or less.

[0011] In this specification, the moisture content is determined by the Karl Fischer method.

[0012] The coating liquid for charge transport layer in the present invention contains fluorene, fluorene, 2,
7-dinitro-9-fluorenone, 4H-indeno(1
,2,6)thiophen-4-one,3,7-dinitro-
Dibenzothiophene-5-oxide, 1-bromopyrene, 2-phenylpyrene, carbazole, 3-phenylcarbazole, 2-phenylindole, 2-phenylnaphthalene, oxazole, oxadiazole, oxatriazole, triphenylamine, imidazole, chrysene, Tetrafen, acriden, various hydrazones,
Styryl compound, poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, 1-phenyl-
3-(4-diethylaminostyryl)-5-(4-diethylaminophenyl)pyrazoline, polyvinylpyrene,
2-phenyl-4-(4-diethylaminophenyl)-
5-phenyloxazole, polyvinylindoquinoxaline, 1,1-bis(p-diethylaminophenyl)
-4,4-diphenyl-1,3-butadiene, polyvinylbenzothiophene, polyvinylanthracene, polyvinylacridine, polyvinylpyrazoline, derivatives thereof, etc. can be used singly or in combination of two or more, and as a binder, silicone Resin, polyamide resin, polyurethane resin, polyester resin, epoxy resin, polyarylate resin, polyetherimide resin, polyethersulfone resin, polyketone resin, polycarbonate resin,
Polystyrene resin, polymethacrylate resin, polyacrylamide resin, polybutadiene resin, polyisoprene resin, melamine resin, benzoguanamine resin, polychloroprene resin, polyacrylonitrile resin, ethyl cellulose resin, nitrocellulose resin, urea resin, phenol resin, phenoxy resin, polyvinyl butyral Resins, formal resins, vinyl acetate resins, vinyl acetate/vinyl chloride copolymers, polyester carbonate resins, and the like can be used singly or in combination of two or more.

[0013] If necessary, plasticizers such as halogenated paraffins, dimethylnaphthalene, and dibutyl phthalate, phenol-based and phosphorus-based ozone deterioration inhibitors, amine-based anti-aging agents, methanesulfonic acid, and dodecylbenzenesulfonic acid are also added. , addition of sulfone-based curing catalysts such as dinonylnaphthalenedisulfonic acid, fluidity imparting agents such as Modaflow (manufactured by Monsanto Chemical Company) and Acronal 4F (manufactured by Basf Corporation), pinhole control agents such as benzoin and dimethyl phthalate, etc. Acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dioxane, toluene, ethyl acetate, methylene chloride, toluene, xylene, cellosolve, 1,1,2-
Trichloroethane, methanol, isopropyl alcohol, isobutyl alcohol, n-butyl alcohol, 1
, 2-dichloroethane or the like.

[0014] When producing the coating solution for the charge transport layer in the present invention, the coating solution prepared by dissolving the various components described above is treated with a molecular sieve whose micropores have an effective diameter of 3A or less. It is preferable to do so. The size of the molecular sieve used here is not limited, but it is preferable that the effective diameter of the micropores is 3A or less.

[0015] When the effective diameter of the micropore exceeds 3A,
Components other than water in the coating solution, such as the dispersion solvent and binder resin, tend to be adsorbed by the molecular sieve, resulting in poor solubility and solution stability. Molecular sieves whose micropores have an effective diameter of 3A or less are, for example, zeolite 3A (
Available commercially as Union Showa Co., Ltd.).

The coating solution is treated by adding 10 parts by weight or more of molecular sieve to 100 parts by weight of the coating solution.
This is preferably carried out by stirring for more than an hour. If the amount of molecular sieve is less than 10 parts by weight, dehydration is insufficient and a uniform coating solution for the charge transport layer tends to be difficult to obtain. Furthermore, if the stirring time is short, dehydration tends to be insufficient.

[0017] The electrophotographic photoreceptor is obtained, for example, by providing an undercoat layer as required on a conductive substrate, and then forming a charge generation layer and a charge transport layer.

[0018] Here, as the conductive substrate, conductive materials such as conductively treated paper or plastic film, a plastic film laminated with metal foil such as aluminum, a metal plate, a metal drum, etc. can be used.

A known undercoat layer is provided on the conductive substrate as described above, if necessary. As the undercoat layer, for example, fine particles of titanium oxide, alumina, zirconia, lanthanum lead zirconate titanate, titanium black, silica, lead titanate, barium titanate, etc., polyamide resin,
Examples include phenol resin, casein, melamine resin, benzoguanamine resin, polyurethane resin, epoxy resin, cellulose, and polyvinyl butyral resin. These fine particles and resins can be used alone or in combination of two or more. In particular, when using fine particles, it is desirable to use them together with a resin because the resin can be adsorbed to the fine particles and a smooth film can be obtained.

[0020] The undercoat layer is formed by dipping coating, spray coating, roll coating, applicator coating, or wire bar coating on the conductive substrate using a coating liquid in which the fine particles and/or resin are dispersed and dissolved in a solvent. It can be formed by coating using a coating method such as and drying.

In this case, the solvents used include acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, toluene, ethyl acetate, methylene chloride, toluene, xylene, cellosolve, 1,1,2-trichloroethane, methanol, isopropyl alcohol,
Isobutyl alcohol, n-butyl alcohol 1,2-
There are solvents such as dichloroethane. Thickness of undercoat layer: 0.
01-20.0 μm, preferably 0.1-3.0 μm
It is. If the thickness is less than 0.01 μm, it becomes difficult to uniformly form the undercoat layer, and if it exceeds 20.0 μm, the electrophotographic properties tend to deteriorate. A charge generation layer is provided on the undercoat layer formed as described above. The charge generating layer includes a photoconductive material, a binder, and other optional additives.

Examples of the photoconductive substance used in the charge generation layer include azoxybenzene type, disazo type, trisazo type, benzimidazole type, polycyclic quinoline type, indigoid type, quinacridone type, phthalocyanine type, naphthalocyanine type, and pyrrolo. Examples include organic pigments such as pyrrole-based, perylene-based, methine-based pigments, and derivatives thereof.

As the binder for the charge generation layer, the same binder as for the charge transport layer can be used. The binder is preferably used in an amount of 5 to 200 parts by weight, more preferably 10 to 100 parts by weight, based on 100 parts by weight of the photoconductive material. If the amount is less than 5 parts by weight, the binder resin will not be sufficiently adsorbed to the photoconductive substance, so that the film of the charge generation layer will tend to be non-uniform and the image quality will tend to be poor. If it exceeds 200 parts by weight, sensitivity tends to decrease and residual potential tends to increase. Further, the same additives as those for the charge transport layer can be used in the charge generation layer.

The charge generating layer contains a photoconductive material, binder and additives such as acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, toluene, ethyl acetate, methylene chloride, toluene, xylene, cellosolve, 1,1,2- After uniformly dissolving or dispersing in a solvent such as trichloroethane, methanol, isopropyl alcohol, isobutyl alcohol, n-butyl alcohol 1,2-dichloroethane, this coating solution is applied onto the undercoat layer by dip coating method or spray coating method. It can be formed by coating using a coating method such as , roll coating, applicator coating, wire bar coating, etc., and drying.

[0025] Thickness of the charge generation layer is usually 0.01 to 2.0μ.
m, preferably 0.1 to 0.8 μm. If the thickness is less than 0.01 μm, it becomes difficult to uniformly form the charge generation layer, and if it exceeds 2.0 μm, the electrophotographic properties tend to deteriorate.

After forming the charge generation layer as described above, the charge transport layer coating solution produced as described above is further applied by dip coating on this layer in an environment with a relative humidity of 65% or less. It can be formed by coating using a coating method such as a coating method, a spray coating method, a roll coating method, an applicator coating method, a wire bar coating method, and the like, and drying it.

The binder resin for the charge transport layer is desirably used in an amount of 450 parts by weight or less per 100 parts by weight of the charge transport layer material so as not to deteriorate the electrophotographic properties. In view of film properties, it is desirable to use 50 parts by weight or more. Further, additives such as a plasticizer, a fluidity imparting agent, and a pinhole control agent can be included as necessary.

The thickness of the charge transport layer is usually 5 to 50 μm, preferably 8 to 30 μm. If this thickness is less than 5 μm, the potential will be low at the initial stage, and if it exceeds 50 μm,
Electrophotographic properties tend to deteriorate.

A protective layer may be formed on the charge transport layer formed as described above. The thickness of the protective layer is 0.01
~10 μm, preferably 0.1 to 3 μm. If this thickness is less than 0.01 μm, the effect of the protective layer is small;
Durability is poor, and if it exceeds 10 μm, sensitivity tends to decrease and residual potential increases.

When printing is performed using the electrophotographic photoreceptor of the present invention, after charging and exposing in the same manner as before,
All you have to do is develop it, transfer the image onto plain paper, and fix it.

[0031]

EXAMPLES Next, the present invention will be explained in detail based on Examples, but the present invention is not limited thereto.

The materials used in the following examples are listed below. Abbreviations are shown in parentheses. (1) Charge-generating organic pigment τ-type metal-free phthalocyanine (τ-H2Pc) (manufactured by Toyo Ink Co., Ltd.) (2) Charge transport substance 1,1-bis(p-diethylaminophenyl)-4,4
-diphenyl-1,3-butadiene (PBD)

003
3) (3) Binder (A) MX1970 (MX1970) for undercoat layer Solid content 100% (manufactured by Nippon Rilsan Co., Ltd.) Butylated melamine resin Melan 2000 (ML2000) with a bound formaldehyde number of 4.0 and a methylol group number of 1.0 ) Solid content 50% (manufactured by Hitachi Chemical Co., Ltd.)

(B) For charge generation layer Brominated phenoxy resin YPB-43 (YPB-43) Solid content 40% (manufactured by Toto Kasei Co., Ltd.)

(C) Polycarbonate resin N2200 (N
2200) Solid content 100% (manufactured by Idemitsu Kosan)

[Chemical 1] Polycarbonate resin TS2050 (
TS2050) Solid content 100% (manufactured by Teijin Chemicals)

[Chemical formula 2] Polycarbonate resin PH-PC (P
H-PC) Solid content 100% (manufactured by Idemitsu Kosan)

[Chemical formula 3] Polycarbonate resin TP-PC (T
P-PC) Solid content 100% (manufactured by Idemitsu Kosan)

[C4]

Comparative Example 1 70g of MX1970, 140g of ML2000 and 4
．． 2 g of trimellitic acid was completely dissolved in 3600 g of a 1:1 mixed solvent of methanol and methylene chloride. This solution was poured into an aluminum drum (outer diameter 120 mmφ, length 48 mm).
6mm, thickness 4mm) by dip coating method,
It was dried at 0° C. for 30 minutes to form an undercoat layer with a thickness of 0.3 μm.

Next, 100g of τ-H2Pc, 200g
YPB-43, 3700 g of 1,2-dichloroethane was dispersed for 80 hours using an ultrasonic disperser. The resulting charge generation layer coating solution was applied onto the undercoat layer by dip coating, and dried at 140° C. for 30 minutes to form a charge generation layer with a thickness of 0.3 μm.

Next, 120 g of PBD and 280 g of N
2200 was completely dissolved in 2400 g of methylene chloride. This solution was coated on the charge generation layer having the undercoat layer by dip coating in an environment with relative humidity of 65%.
It was dried at 00° C. for 30 minutes to form a charge transport layer with a film thickness of 17 μm, thereby forming an electrophotographic photoreceptor.

The water content of this charge transport layer coating solution was measured by the Karl Fischer method and was found to be 0.06% by weight.

Comparative Example 2 Using the materials and procedures shown in Comparative Example 1, an aluminum drum (outer diameter 120 mmφ, length 486 mm, thickness 4 m
A subbing layer having a thickness of 0.3 μm was formed on top of (m). Next, using the materials and procedures shown in Comparative Example 1, a charge generation layer with a thickness of 0.3 μm was formed on the above-mentioned undercoat layer.

Next, 144 g of PBD and 336 g of T
S2050 was completely dissolved in 2200 g of methylene chloride. Coating this solution on the charge generation layer having the undercoat layer by dip coating in an environment with relative humidity of 75%,
This was dried at 100° C. for 30 minutes to form a charge transport layer with a thickness of 16 μm, thereby forming an electrophotographic photoreceptor.

The water content of this charge transport layer coating solution was measured by the Karl Fischer method and was found to be 0.07% by weight.

Comparative Example 3 Using the materials and operations shown in Comparative Example 1, an aluminum drum (outer diameter 120 mmφ, length 486 mm, thickness 4 m
A subbing layer having a thickness of 0.3 μm was formed on top of (m). Next, using the materials and procedures shown in Comparative Example 1, a charge generation layer with a thickness of 0.3 μm was formed on the above-mentioned undercoat layer.

Next, 120 g of PBD and 280 g of T
P-PC was completely dissolved in 2500 g of 1,2-dichloroethane. This solution was coated on the charge generation layer having the undercoat layer by dip coating in an environment with relative humidity of 40%, and dried at 110°C for 30 minutes to form a charge transport layer with a thickness of 18 μm. Then, an electrophotographic photoreceptor was formed.

The water content of this charge transport layer coating solution was measured by Karl Fischer method and was found to be 0.10% by weight.

Comparative Example 4 Using the materials and operations shown in Comparative Example 1, an aluminum drum (outer diameter 120 mmφ, length 486 mm, thickness 4 m
A subbing layer having a thickness of 0.3 μm was formed on top of (m). Next, using the materials and procedures shown in Comparative Example 1, a charge generation layer with a thickness of 0.3 μm was formed on the above-mentioned undercoat layer.

Next, 120 g of PBD and 280 g of P
H-PC was completely dissolved in 2400 g of tetrahydrofuran. This solution was coated on the charge generation layer having the undercoat layer by dip coating in an environment with relative humidity of 70%, and dried at 110°C for 30 minutes to form a charge transport layer with a thickness of 17 μm. Then, an electrophotographic photoreceptor was formed.

The water content of this charge transport layer coating solution was measured by the Karl Fischer method and was found to be 0.1% by weight.

Example 1 Using the materials and operations shown in Comparative Example 1, an aluminum drum (outer diameter 120 mmφ, length 486 mm, thickness 4 m
A subbing layer having a thickness of 0.3 μm was formed on top of (m). Next, using the materials and procedures shown in Comparative Example 1, a charge generation layer with a thickness of 0.3 μm was formed on the above-mentioned undercoat layer.

Next, 120 g of PBD and 280 g of P
H-PC was completely dissolved in 2400 g of tetrahydrofuran, 300 g of molecular sieve was added, and the mixture was further stirred for 48 hours using a magnetic stirrer. Coating the obtained solution on the charge generation layer having the undercoat layer by dip coating in an environment with a relative humidity of 65%,
It was dried at 110° C. for 30 minutes to form a charge transport layer with a thickness of 18 μm, thereby forming an electrophotographic photoreceptor. The water content of this charge transport layer coating liquid was measured by the Karl Fischer method and was found to be 0.005% by weight.

Example 2 Using the materials and operations shown in Comparative Example 1, an aluminum drum (outer diameter 120 mmφ, length 486 mm, thickness 4 m
A subbing layer having a thickness of 0.3 μm was formed on top of (m). Next, using the materials and procedures shown in Comparative Example 1, a charge generation layer with a thickness of 0.3 μm was formed on the above-mentioned undercoat layer. Next, 144 g of PBD and 336 g of TS2050 were completely dissolved in 2200 g of methylene chloride, and 300 g of molecular sieve was added thereto, followed by additional stirring for 48 hours using a magnetic stirrer. This solution was coated on the charge generation layer having the undercoat layer by dip coating in an environment of 50% relative humidity, and dried at 100°C for 30 minutes to form a charge transport layer with a thickness of 16 μm. Then, an electrophotographic photoreceptor was formed. The water content of this charge transport layer coating liquid was measured by Karl Fischer method and was 0.007% by weight.
Met.

Example 3 Using the materials and procedures shown in Comparative Example 1, an aluminum drum (outer diameter 120 mmφ, length 486 mm, thickness 4 m) was prepared.
A subbing layer having a thickness of 0.3 μm was formed on top of (m). Next, using the materials and procedures shown in Comparative Example 1, a charge generation layer with a thickness of 0.3 μm was formed on the above-mentioned undercoat layer. Next, 120 g of PBD and 280 g of N2200 were completely dissolved in 2400 g of methylene chloride, and 300 g of molecular sieve was added thereto, followed by additional stirring for 48 hours using a magnetic stirrer. The obtained solution was coated on the charge generation layer having the undercoat layer by dip coating in an environment with relative humidity of 55%, and dried at 100° C. for 30 minutes to form a charge transport layer with a thickness of 17 μm. was formed to form an electrophotographic photoreceptor. The water content of this charge transport layer coating liquid was measured by Karl Fischer method and was 0.01% by weight.
Met.

Example 4 Using the materials and operations shown in Comparative Example 1, an aluminum drum (outer diameter 120 mmφ, length 486 mm, thickness 4 m) was prepared.
A subbing layer having a thickness of 0.3 μm was formed on top of (m). Next, using the materials and procedures shown in Comparative Example 1, a charge generation layer with a thickness of 0.3 μm was formed on the above-mentioned undercoat layer. Next, 120 g of PBD and 280 g of TP-PC were
The mixture was completely dissolved in 2,500 g of 2-dichloroethane, and 300 g of molecular sieve was added thereto, followed by additional stirring for 48 hours using a magnetic stirrer. The obtained solution was coated on the charge-generating layer having the undercoat layer by dip coating in an environment with relative humidity of 40%, and dried at 110°C for 30 minutes to form a charge transport film with a thickness of 18 μm. A layer was formed to form an electrophotographic photoreceptor. The water content of this charge transport layer coating liquid was measured by Karl Fischer method and was 0.
It was 0.01% by weight.

The appearance, electrophotographic properties, and images of the charge transport layers of the electrophotographic photoreceptors obtained in the Comparative Examples and Examples were evaluated.

[0055] The appearance was visually observed. The electrophotographic properties were evaluated using an image evaluation machine (negative charging, reversal development method) based on the circumferential deviation of the surface potential (Vo) and the circumferential deviation of the residual potential (Vr).

The image (fog) was evaluated using an image evaluation device (negative charging, reversal development method).

Table 1 shows the appearance of the charge transport layer of the photoreceptor.
Electrophotographic characteristics■Evaluation results of image quality are shown. From the results shown in Table 1, brushing occurred in the appearance of the charge generation layer of the electrophotographic photoreceptors of Comparative Examples 1 to 4, and Vo
The deviation of Vr in the circumferential direction was as large as 50 V or more, and fog occurred in the image.

[0058]

[Table 1]

On the other hand, in the electrophotographic photoreceptors produced using the charge transport layer coating liquids of the present invention (Examples 1 to 4), the appearance of the charge transport layer was extremely good, and the Vo and Vr values were very good. The deviation in the circumferential direction was small at 20 V or less, and no fogging occurred in the image. Therefore, by using the coating method and coating liquid for a charge transport layer according to the present invention, it is possible to fully support high-speed printers that require high image quality.

In the coating liquid for charge transport, the resin binder is uniformly dissolved in the solvent together with the substance having the charge transport function, but when the amount of water in the solvent increases, the resin binder and the substance having the charge transport function dissolve. The solubility decreases, and brushing occurs because moisture in the coating environment is incorporated into the wet coating film due to the latent heat of vaporization during coating, but by reducing the moisture content, the resin in the charge transporting coating solution Since the binder and the substance having a charge transport function are uniformly dissolved, it is thought that brushing does not occur even if moisture in the coating environment is incorporated into the wet coating film due to the latent heat of vaporization. Therefore, it is considered that high image quality has been achieved.

[0061]

[Effects of the Invention] According to the manufacturing method of the present invention, an electrophotographic photoreceptor having excellent properties such as image properties can be obtained.

Claims (1)

[Claims] 1. An electronic device characterized in that a charge transport layer is formed using a charge transport layer coating liquid having a water content of 0.01% by weight or less in an environment with a relative humidity of 65% or less. Manufacturing method of photographic photoreceptor.