JPH10133398A - Electrophotographic photoreceptor and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor which has the adequate surface roughness between photosensitive layers, is free from the degradation in sensitivity and fogging and has excellent durability. SOLUTION: This photoreceptor is formed by stacking cylindrical base materials 1A, 1B while aligning their cylindrical axes to each other and applying a coating liquid 2 sent by a liquid feeding means from a coating liquid tank 5 onto the outer peripheral surfaces of these base materials, applying photoreceptor constitution layers A on the base materials 1A, 1B and, further, applying separate constitution layers B adjacent thereto on these layers while perpendicurally pushing up the base materials 1A, 1B from below to above. In this case, the surface roughness at the reference length 0.25 of the boundary between the constitution layers A and the constitution layer B is specified to 0.05 to 0.5μm. The surface roughness of the boundary at the reference length 2.5mm is specified to <=2.0μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member used for a copying machine, a printer and the like, and more particularly, to an electrophotographic photosensitive member on an outer surface of a substrate having a continuous surface formed endlessly.
The present invention relates to an electrophotographic photoreceptor manufactured by a coating apparatus that uniformly applies a coating liquid, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, spray coating, dip coating, blade coating, roll coating, and the like have been used as means for uniformly coating a thin film on the outer surface of a substrate having a continuous surface formed endlessly. Are studied.

In particular, for a thin and uniform coating such as an electrophotographic photosensitive drum, studies are being made to develop a coating apparatus having excellent productivity. However, the conventional method for coating an endless substrate has disadvantages such as a failure to obtain a uniform coating film and poor productivity.

In the spray coating method, the solvent evaporates before the coating droplet ejected from the spray gun reaches the outer peripheral surface of the substrate having the continuous surface formed endlessly. The minute concentration rises. When the viscosity of the applied liquid drops increases and the liquid drops reach the surface, the liquid droplets do not spread sufficiently on the surface, or the dried and solidified particles adhere to the surface.
Good surface smoothness cannot be obtained. In addition, it is very difficult to control the film thickness because the arrival rate of the liquid droplets on the substrate having the continuous surface is not 100%, and there is a loss of the coating liquid or the coating liquid is partially non-uniform. Further, in the case of a polymer solution or the like, a so-called stringing phenomenon may occur, so that the solvent and the resin used are limited.

[0005] In the blade coating method and the roll coating method, for example, a blade or a roll is arranged in the longitudinal direction of a cylindrical substrate, and the cylindrical substrate is rotated to perform coating, and the cylindrical substrate is rotated once. The rear blade or roll is retracted. However, when the blade or the roll is retracted, there is a disadvantage that a part of the coating film thickness is thicker than other parts due to the viscosity of the coating liquid, and a uniform coating film cannot be obtained.

[0006] The dip coating method improves the above-mentioned points of poor surface smoothness of the coating solution and uniformity of the coating film.

However, the coating film thickness is governed by the physical properties of the coating liquid, for example, viscosity, surface tension, density, temperature, etc. and the coating speed, and the adjustment of the physical properties of the coating liquid is very important. Generally, the coating speed cannot be increased, and a certain amount or more of liquid is required to fill the coating liquid tank. Further, when the layers are overlaid, there are disadvantages such as the lower layer components dissolving, the layer interface being disturbed, and the coating solution tank being easily contaminated.

Therefore, as disclosed in Japanese Patent Application Laid-Open No. 58-189061, a circular amount-regulated type coating apparatus (including a slide hopper type coating apparatus) has been developed. The circular hopper type slide hopper type coating apparatus will be described. While continuously moving a cylindrical base material having a continuous peripheral surface formed endlessly in the longitudinal direction thereof, it surrounds the periphery thereof in a ring shape and forms a cylindrical shape. The coating liquid is applied to the outer peripheral surface of the substrate. Further, the coating apparatus includes an annular liquid storage chamber, a supply port that supplies a coating liquid from outside to a part of the liquid storage chamber, and a coating liquid distribution slit that opens inside the liquid storage chamber. Have. The coating solution flowing out of the slit is caused to flow down onto a slide surface that is inclined obliquely downward, and a bead is formed in a slight gap between the slide edge of the lip at the lower end of the slide surface and the cylindrical substrate,
This is applied to the outer peripheral surface of the cylindrical substrate as it moves.

[0009]

However, even when the above-mentioned slide hopper type coating apparatus of the circular quantity control type is used, there is still a problem of a variation in the film thickness between layers, and it is still unsatisfactory when used as a highly durable photoreceptor. is not.

The present invention has been proposed in view of the above-mentioned circumstances, and an object of the present invention is to provide a photosensitive member having an appropriate surface roughness between layers and excellent durability, and a method of manufacturing the same. It is in.

It is a further object of the present invention to provide a so-called simultaneous multi-layer coating in which a plurality of coating layers are simultaneously formed on a substrate from the same coating apparatus. It is to provide a manufacturing method thereof.

It is a further object of the present invention to provide a so-called sequential multi-layer coating in which a coating layer is sequentially formed on a substrate from a plurality of coating apparatuses, and a photosensitive member having an appropriate surface roughness between layers and excellent durability. It is to provide a manufacturing method thereof.

[0013]

The object of the present invention is achieved by adopting the following constitution.

(1) The cylindrical base materials are stacked with their cylinder axes aligned, and the coating liquid sent from the coating liquid tank by the liquid feeding means is applied to the outer peripheral surface of the base material while pushing vertically upward from the bottom. In an electrophotographic photoreceptor obtained by coating a photoreceptor constituent layer A on a base material and further adjoining another constituent layer B, a reference for a boundary surface between the constituent layers A and B Surface roughness Rz1 at a length of 0.25 mm is 0.05 to 0.5 μm
m, the surface roughness Rz of the interface at the reference length of 2.5 mm
2 is 2.0 μm or less.

(2) The electrophotographic photoreceptor according to (1), wherein the device used for the coating is a circular amount control type coating device.

(3) The electrophotographic photosensitive member according to (2), wherein the circular amount-regulating type coating device is a slide hopper type coating device.

(4) The constitution (1), (2) or (3), wherein the photoconductor constituting layer A is a charge transporting layer (CTL) and the constituting layer B is a protective layer (OCL). Electrophotographic photoreceptor.

(5) The cylindrical base materials are stacked with their cylinder axes aligned, and a coating solution is continuously applied on the outer peripheral surface of the base material while being vertically pushed upward from the bottom to form a photosensitive member constituting layer A. Further, in a method of manufacturing an electrophotographic photoreceptor obtained by coating another component layer B adjacent thereto, the surface roughness of the boundary surface between the component layer A and the component layer B at a reference length of 0.25 mm Rz
1. A method for producing an electrophotographic photoreceptor, wherein the coating is performed so that 1 is 0.05 to 0.5 μm and the surface roughness Rz2 of the interface at a reference length of 2.5 mm is 2.0 μm or less.

(6) The method for producing an electrophotographic photosensitive member according to (5), wherein the coating device is a circular amount-regulating type coating device.

(7) The method of manufacturing an electrophotographic photosensitive member according to (6), wherein the circular amount-regulating type coating device is a slide hopper type coating device.

(8) The method for producing an electrophotographic photosensitive member according to (6) or (7), wherein the coating is performed by the simultaneous multilayer coating method using the circular amount-regulated coating device.

(9) The method for producing an electrophotographic photoreceptor according to (6) or (7), wherein the coating is performed by a sequential coating method using the circular amount-regulating type coating apparatus.

The constituent layers of the present invention mean all layers applied on the cylindrical substrate of the photoreceptor, and include an intermediate layer (undercoat layer), a charge transport layer, a charge generation layer, a charge generation transport layer, Refers to a layer called a protective layer or the like. In addition, Rz1 and Rz2 between the constituent layers are the roughness of the portion schematically shown in FIG. 1 (the constituent layer A is 10 and the constituent layer B is 11).

For the measurement of the surface roughness, the coating layer was peeled off from the produced photosensitive drum, and the cross section was measured by a cross section method. Rz1 and Rz2 are the same as Rz described in JIS B-0601, but a reference length of 2.5 mm was used as an Rz2 waviness component, and Rz1 used a reference length of 0.25 mm.

If Rz1 is larger than 0.5 μm, the transfer of carriers (charges) is impaired due to disturbance at the interface, and the sensitivity and image quality are reduced. On the other hand, if it is smaller than 0.05 μm, the degree of mutual mixing at the interface is poor, and the carrier transmission is deteriorated.

Rz2 corresponds to the undulation component. When Rz2 is larger than 2.0 μm, for example, in the case of copying a large number of sheets, the surface layer of the photoreceptor is shaved and thinned. It is liable to decrease and cause image unevenness.

In order to improve the performance of the electrophotographic photosensitive member, it is important to improve coating accuracy and stabilization, and among them, a circular hopper type coating apparatus can be said to be the coating method most suitable for this requirement.

Normally, when a multilayer is formed by dip coating, the lower polymer layer is dissolved during coating. Conversely, in the case of an overlying polymer layer having no affinity for each other so as not to be dissolved, carriers are not smoothly transmitted between the layers, and adverse effects such as an increase in residual potential and fogging in multiple copies are caused. Therefore, a certain degree of affinity is required, but balance is difficult.

The turbulence between the layers is closely related to the solvent composition S of the upper layer and the binder composition P of the lower layer, and whether a 5 wt% polymer solution of P by S can be prepared at 22 ° C. One standard is how long it takes to evaporate about 70% of the solvent S after contact. In other words, too long will dissolve the lower layer,
The unevenness of the boundary surface becomes severe. In this respect, the coating apparatus of the present invention is advantageous because the time until drying can be extremely shortened even if the affinity for the lower layer is high.

[0030]

FIG. 2 is a schematic sectional view of a coating apparatus according to the present invention. In FIG. 2, an endless cylindrical base material vertically overlapped along a center line Y is shown. 1
A and 1B, and a slide hopper type circular amount regulating type coating apparatus 3 for sequentially applying the coating liquid 2 for a photosensitive layer to the cylindrical substrates 1A and 1B.

As shown in the figure, a hopper coating surface 4 of the coating liquid 2 is formed so as to surround the cylindrical substrate 1A, and the coating liquid 2 supplied to the hopper coating surface 4 is applied to the cylindrical substrate 1A. It is configured to apply sequentially. As the coating method, the annular circular amount-regulating coating device 3 is fixed, and the coating is performed from the upper end while the cylindrical substrate 1A is moved upward along the center line Y in the arrow direction. The circular amount control type coating device 3
In order to supply the coating liquid 2 to the hopper coating surface 4, a liquid feeding pump 6-1 and a liquid feeding pipe 6-6 are provided from a coating liquid tank 5 provided outside.
1 '(liquid supply means A) and the coating liquid supply section 6A are connected to the annular circular amount regulating type coating apparatus 3 to supply the coating liquid 2.

Next, the supplied coating liquid 2 is supplied to an annular coating liquid distribution chamber 7 formed in the circular circular amount regulating type coating apparatus 3, and is supplied from a coating liquid distribution slit 8 to an endless coating liquid outlet. The coating liquid 2 is continuously supplied to the hopper coating surface 4 from 9, and the coating liquid 2 is applied to the entire peripheral surface of the cylindrical substrate 1A. Reference numeral 12 denotes a liquid reservoir for storing the coating liquid 2 dropped from the hopper coating surface 4.

FIG. 3 is a partially cutaway perspective view of the circular amount regulating type coating apparatus 3 shown in FIG. In addition, the circular amount control type coating apparatus is not necessarily a slide hopper type, but a cylindrical base material is passed through an annular coating machine, and a volume-controlled coating liquid is discharged from the annular coating machine to form a cylindrical base. This refers to a coating apparatus of a type that forms a liquid film on a material, but a slide hopper type is shown here because a slide hopper type is the most typical type.

FIG. 4 shows a coating solution which becomes a photoreceptor on cylindrical substrates 1A and 1B formed endlessly using the annular circular amount-regulating coating device 3 used in the embodiment of FIGS. 1 is a schematic cross-sectional view of a coating apparatus showing a preferred embodiment example (simultaneous multilayer coating method) of the present invention in which multiple layers are simultaneously coated.

In FIG. 4, the cylindrical substrates 1A and 1B which are vertically overlapped along the center line Y, and the cylindrical substrates 1
Reference numerals A and 1B denote an annular circular amount-regulating coating device 3 for sequentially coating the photosensitive coating liquid 2. As shown in FIG.
A hopper coating surface 4 of the coating liquids 2 and 2A is formed so as to surround the hopper A, and the coating liquids 2 and 2A supplied to the hopper coating surface 4 are formed.
Are sequentially applied to the cylindrical substrate 1A. As the coating method, the annular circular amount-regulating coating device 3 is fixed, and the coating is performed from the upper end while the cylindrical substrate 1A is moved upward along the center line Y in the arrow direction.
A coating liquid tank 5 provided outside for supplying the coating liquids 2 and 2A to the hopper coating surface 4 of the circular amount-regulating type coating apparatus 3.
From the liquid sending pump 6-1 and the liquid sending pipe 6-1 '(liquid sending means A)
Then, the coating liquid is sent from the coating liquid supply unit 6A to the coating liquid distribution chamber 7.

The liquid supply from the coating liquid tank 51 to the coating liquid distribution chamber 71 is performed in the same manner.

Next, the applied coating liquids 2 and 2A are supplied to the annular coating liquid distribution chamber 7 formed in the circular amount-control type coating apparatus 3, and the coating liquid 2 is supplied thereto. The coating liquid 2A is supplied to an annular coating liquid distribution chamber 71 formed in the apparatus 3. First, the applied coating liquid 2 is continuously supplied to the hopper coating surface 4 from an endless coating liquid outlet 9 through a coating liquid distribution slit 8, and is first applied to the entire peripheral surface of the cylindrical substrate 1A. The application liquid 2 is applied.

Further, the coating liquid 2A is supplied to the coating liquid distribution chamber 71. The supplied coating liquid 2A is continuously supplied from the coating liquid distribution slit 81 to the coated coating liquid 2 from an endless coating liquid outlet 91, and is first applied to the entire peripheral surface of the cylindrical substrate 1A. The liquid 2 is overlaid with the coating liquid 2A.

Reference numeral 12 denotes a liquid reservoir for storing the coating liquid 2 dropped from the hopper coating surface 4.

FIG. 5 shows the annular circular amount regulating type coating apparatus 3 used in the embodiment of FIG. 2 arranged vertically.
It is a schematic sectional drawing of the coating device which is another preferable embodiment example (sequential multilayer coating method) of this invention. This is also an endlessly formed cylindrical substrate 1 as shown in FIG.
This is an example of an embodiment in which coating liquids A and 1B are multi-layer coated.

First, the coating liquid 2 supplied to the hopper coating surface 4 is sequentially applied to the cylindrical substrate 1A in the same manner as in FIG. As the coating method, the circular amount-regulated coating device 3 is fixed, and the coating is performed from the upper end while the cylindrical substrate 1A is moved upward in the direction of the arrow along the center line Y. In order to supply the coating liquid 2 to the hopper coating surface 4 of the circular amount control type coating apparatus 3, a liquid feeding pump 6-1 and a liquid feeding pipe 6-1 ′ (liquid feeding means A) are provided from a coating liquid tank 5 provided outside. ), The coating liquid is sent from the coating liquid supply section 6A to the coating liquid distribution chamber 7 (the liquid is also sent from the coating liquid tank 52 to the coating liquid distribution chamber 72).

Thus, the coating liquid 2 is supplied to the annular coating liquid distribution chamber 7 formed in the coating apparatus 3, and is continuously supplied to the hopper coating surface 4 from the coating liquid distribution slit 8 through an endless coating liquid outlet 9. The first layer of the coating liquid 2 is applied to the entire peripheral surface of the cylindrical substrate 1A.

Further, a circular amount regulating type coating device 32 is provided above the circular amount regulating type coating device 3.

The coating liquid 2 on which the first coating liquid 2 has been applied is dried, and the cylindrical substrate 1A rises in the direction indicated by the arrow and enters the hopper coating surface 42 of the circular circular amount control type coating apparatus 32. I do. The coating liquid 2A supplied to the hopper coating surface 42 is sequentially layer-coated on the coating liquid 2 applied to the cylindrical substrate 1A. As the coating method, the annular circular amount-regulating coating device 32 is fixed in the same manner as described above, and the multilayer coating is performed from the upper end while the cylindrical substrate 1A is moved upward in the direction of the arrow along the center line Y.

In order to supply the coating liquid 2A to the hopper coating surface 42 of the ring-shaped circular amount regulating type coating device 32, the coating liquid supply section of the liquid feed pump is moved from the coating liquid tank 52 provided outside to the annular circular amount. It is connected to the regulated coating device 32 (the connection method is the same as that for the coating device 3), and the coating liquid 2A is supplied. Next, the supplied coating liquid 2A is applied to the annular coating liquid distribution chamber 72 formed in the circular amount control type coating apparatus 32.
The coating liquid 2 is supplied to the hopper coating surface 42 from the coating liquid outlet 92 which is supplied endlessly through the coating liquid distribution slit 82.
A is continuously supplied, and the coating liquid 2A is
A is applied to the entire peripheral surface of the application liquid 2 applied to A.

The cylindrical substrate in the electrophotographic photoreceptor of the present invention includes aluminum, copper, gold, silver on metal drums and sheets such as aluminum, copper, iron, zinc, nickel, etc., paper, plastic or glass. Metal, such as platinum, palladium, titanium, nickel-chromium, stainless steel, copper-indium, or a conductive metal oxide such as indium oxide, tin oxide, metal foil laminated, or carbon Known materials such as drums, sheets, and plates that have been subjected to conductive treatment by dispersing black, indium oxide, tin oxide-antimony oxide powder, metal powder, copper iodide, etc. in a binder resin and applying the same. Can be used, but the present invention is not limited to these.

Further, if necessary, the surface of the cylindrical substrate may be
Various processes can be performed within a range that does not affect image quality. For example, oxidation treatment, chemical treatment, coloring treatment, and the like of the surface can be performed.

Further, an undercoat layer can be further provided between the cylindrical substrate and the charge generation layer (CGL), and this undercoat layer is electrically conductive cylindrical in the photosensitive layer having a laminated structure during charging. Acts as an adhesive layer to prevent charge injection from the cylindrical substrate into the photosensitive layer and to adhere and hold the photosensitive layer integrally to the conductive cylindrical substrate, or reflected light from the cylindrical substrate And the like. The resin used for the undercoat layer (UCL) is polyethylene, polypropylene, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, epoxy resin, polyester resin, alkyd resin,
Known resins such as polycarbonate, polyurethane, polyimide resin, vinylidene chloride resin, polyvinyl acetal resin, vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol, water-soluble polyester, nitrocellulose or casein, and gelatin can be used. It is not limited.

The undercoat layer has a thickness of 0.01 to 10 μm.
m, preferably 0.05 to 2 μm.

The charge generation layer may be, for example, an azo dye such as a monoazo dye, a disazo dye or a trisazo dye, a perylene dye such as perylene anhydride or perylene imide, an indigo dye such as indigo or thioindigo, anthraquinone, pyrenequinone, or the like. Polycyclic quinones such as flapanthrones, quinaglidone dyes, bisbenzimidazole dyes, indathrone dyes, squarylium dyes, metal phthalocyanines, phthalocyanine pigments such as metal-free phthalocyanines, pyrylium salt dyes, thiapyrylium salt dyes and polycarbonates Various known charge generating substances (CGM), such as a eutectic complex formed from, are dissolved or dispersed in a solvent together with a suitable binder resin and, if necessary, a charge transporting substance (CTM), and then coated. .

As a method for dispersing the charge generating substance in the resin, a ball mill dispersion method, an attritor dispersion method, a sand mill dispersion method, or the like can be used. At this time, the charge generating substance has a volume average particle diameter of 5 μm or less, preferably 2 μm or less.
It is effective to set the particle size to not more than m, most preferably not more than 0.5 μm. As a solvent used for these dispersions, methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, dioxane, Ordinary organic solvents such as tetrahydrofuran, methylene chloride, chloroform, 1,2-dichloroethane, monochlorobenzene, and xylene can be used alone or in combination of two or more.

The thickness of the charge generation layer used in the present invention is generally 0.1 to 5 μm, preferably 0.2 to 2 μm.

The charge transport layer (CTL) in the electrophotographic photoreceptor of the present invention is formed by including a charge transport material (CTM) in a suitable binder. As the charge transport material, 2,5-bis (p-diethylaminophenyl)-
Oxadiazole derivatives such as 1,3,4-oxadiazole, 1,3,5-triphenyl-pyrazoline, 1-
Pyrazolin derivatives such as [pyridyl- (2)]-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline; and aromatic tertiary compounds such as triphenylamine, styryltriphenylamine and dibenzylaniline. An amino compound, N, N'-diphenyl-N,
Aromatic tertiary diamino compounds such as N'-bis (3-methylphenyl) -1,1-biphenyl-4,4'-diamine; 3- (4'-dimethylaminophenyl) -5,6
1,2-, 4-triazine derivatives such as -di- (4'-methoxyphenyl) -1,2,4-triazine, hydrazone derivatives such as 4-diethylaminobenzaldehyde-1,1-diphenylhydrazone, 2-phenyl-4 Quinazoline derivatives such as -styryl-quinzoline, benzofuran derivatives such as 6-hydroxy-2,3-di (p-methoxyphenyl) -benzofuran, p- (2,2-diphenylvinyl) -N, N-diphenylaniline and the like α
-Stilbene derivatives, "Journal of Ima
ging Science "29: 7-10 (198
5) Enamine derivatives, carbazole derivatives such as N-ethylcarbazole, poly-N-vinylcarbazoles such as poly-N-vinylcarbazole and derivatives thereof, and poly-γ-carbazolylethylglutanates and derivatives thereof described in 5) , And also pyrene, polyvinylpyrene,
Known charge transport materials such as polyvinyl anthracene, polyvinyl acridine, poly-9-biphenyl anthracene, pyrene-formaldehyde resin, and ethyl carbazole formaldehyde resin can be used, but are not limited thereto. These charge transporting substances can be used alone or in combination of two or more.

Further, as the binder resin in the charge transport layer, polycarbonate resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl acetate resin, butylene-butadiene copolymer , Vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly A known resin such as -N vinylcarbazole can be used, but is not limited thereto. These binder resins can be used alone or in combination of two or more.

The mixing ratio (weight ratio) of the charge transporting material to the binder resin is preferably from 10: 1 to 1: 5. The thickness of the charge transport layer used in the present invention is generally 5 to 50 μm, preferably 10 to 30 μm.

Further, as the solvent used for forming the charge transport layer, aromatic hydrocarbons such as benzene, toluene, xylene and chlorobenzene, ketones such as acetone and 2-butanone, methylene chloride, chloroform, chloride Ordinary organic solvents such as halogenated aliphatic hydrocarbons such as ethylene, and cyclic or linear ethers such as tetrahydrofuran and ethyl ether can be used alone or in combination of two or more.

Further, if necessary, a protective layer (OCL) may be provided on the charge transport layer. The protective layer is used for preventing the charge transport layer from being chemically deteriorated when the photosensitive layer having a laminated structure is charged, and for improving the mechanical strength of the photosensitive layer.

The above-described charge transporting material may be added to the protective layer.

As the binder resin used for the protective layer, a known resin such as a polyamide resin, a polyurethane resin, a polyester resin, an epoxy resin, a polyketone resin, a polycarbonate, a polyvinylketone resin, a polystyrene, and a polyacrylamide resin may be used. it can.

The protective layer must be constructed so as not to substantially impede the passage of light used for image exposure.

The thickness of the protective layer used in the present invention is 0.5 to 2
0 μm, preferably 1 to 10 μm is suitable.

[0062]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1 (Examples and Comparative Examples) As a cylindrical substrate (conductive support), a mirror-finished aluminum drum having a diameter of 80 mm and a height of 355 mm was used. The following coating layers (1) to (4) were coated on the cylindrical substrate by a slide hopper type circular quantity-regulating coating apparatus shown in FIG.

UCL layer The following UCL-1 coating solution composition (polymer concentration: 3 wt%) was prepared on the cylindrical substrate, and coated and dried.
5 μm coating drum A-1 was obtained.

UCL-1 coating liquid composition Vinyl chloride-vinyl acetate copolymer (S-LEC MF-
10 Sekisui Chemical Co., Ltd.) Acetone / cyclohexanone = 10/1 (Vol ratio) The coatability was good.

CGL Layer Coating solution compositions CGL-1, CGL-2 and CGL-3 as shown below were respectively applied to three coating drums A-1 and CGL-3.
Was applied to obtain coating drums B-1, B-2, and B-3.

CGL-1 Coating Liquid Composition Fluorenone-Type Disazo Pigment (CGM-1) 25 g Butyral Resin (Eslec BX-L, manufactured by Sekisui Chemical Co., Ltd.) 10 g Methyl ethyl ketone 1430 ml The above coating liquid composition (solid content: CG
M-1: BX-L = 3: 1) was dispersed using a sand mill for 20 hours.

CGL-2 Coating Liquid Composition Perylene Pigment (CGM-2) 500 g Butyral Resin (S-LEC BX-1 manufactured by Sekisui Chemical Co., Ltd.) 500 g Methyl ethyl ketone 24 l The above coating liquid composition (solid content: CG
M-2: BX-L = 2: 1) was dispersed using a sand mill for 20 hours.

CGL-3 coating solution composition Y-type titanyl phthalocyanine (CGM-3) 100 g Silicone resin (KR-5240 manufactured by Shin-Etsu Chemical Co., Ltd.) 100 g t-butyl acetate 10 l The above coating solution composition (solid content is defined as solid content). Weight ratio CG
M-3: KR-5240 = 2: 1) was dispersed for 17 hours using a sand mill.

The coating properties were good, and no coating unevenness or film thickness variation was observed.

[0071]

Embedded image

CTL Layer A coating liquid composition CTL-1 was prepared on the three coating drums B-1 to B-3 as described below, and the coating drums C-1, C-2 and C-2 having a film thickness of 20 μm were prepared. 3 was obtained. In this case, 70% from the start of coating (when the coating liquid CTL-1 contacts the lower layer)
The time to evaporation was kept within 2 minutes by the rapid drying method.

CTL-1 coating solution composition CTM-1 3000 g Polycarbonate (Z-200 manufactured by Mitsubishi Gas Chemical Company) 5600 g 1,2-dichloroethane 26000 ml

[0074]

Embedded image

Comparative Example 1 The procedure of Example 1 was repeated, except that the coating of Example 1 was carried out by dip coating of an all-layer overflow type. The obtained photosensitive drums are designated D-1 to D-3, respectively. 70 from the start of application of CTL-1 (when the application liquid CTL-1 contacts the lower layer)
% Solvent evaporation took 7 minutes.

The surface roughness of the interface between the obtained photosensitive members B-1 to B-3 and D-1 to D-3 in Example 1 and Comparative Example 1 was measured, and the same type of drum was manufactured by Konica Corporation. U-BIX3
The camera was mounted on a 035 copier and photographed. Table 1 shows the results.

The surface roughness was measured by removing the photosensitive layer from the photosensitive drum similarly prepared and measuring the cross section by a cross section method.

Note that 1,2-dichloroethane as a CTL solvent is a good solvent for each CGL polymer.
% Or more.

In the same manner as in the overflow-type dip coating for applying CTL-1 on B-1 described above, the coating speed was adjusted so that it took 7 minutes from the start of coating to 70% solvent evaporation. Applied. This is designated as D-4.

[0080]

[Table 1]

Example 2 In the same manner as in Example 1, coating was performed up to the CTL layer. However, the thickness of the CTL layer was 15 μm. On this, the following coating composition OC
L-2 was applied in a thickness of 5 μm using the coating apparatus of FIG. C-4, C
-5 and C-6.

OCL-2 coating liquid composition CTM-1 5000 g Polycarbonate (BPZ having a viscosity-average molecular weight of 100,000) 5600 g 1,2-dichloroethane 32000 ml AO agent 100 g Comparative Example 2 Example 2 was the same as Comparative Example 1 in that all layers overflowed. It was applied by dip coating of a mold. D-4 and D
-5 and D-6. Example 1 / Comparative Example 1
Measured and photographed in the same manner as described above. Table 2 shows the results.

[0083]

[Table 2]

As shown in Tables 1 and 2, Rz1 was 0.0
It can be seen that a good photoreceptor having high durability can be obtained when the thickness is 5 to 0.5 μm and Rz2 is 2.0 μm or less.

[0085]

According to the present invention, it is possible to provide a photosensitive member having an appropriate surface roughness between photosensitive layers and excellent durability, and a method for producing the same.

Further, according to the present invention, even in so-called simultaneous multi-layer coating in which a plurality of coating layers are simultaneously formed on a substrate from the same coating apparatus, a photosensitive member having an appropriate surface roughness between photosensitive layers and excellent durability is provided. A manufacturing method can be provided.

Further, according to the present invention, even in so-called sequential multi-layer coating in which a coating layer is sequentially formed on a substrate from a plurality of coating apparatuses, a photosensitive member having an appropriate surface roughness between photosensitive layers and excellent durability is provided. A manufacturing method can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating Rz1 and Rz2 according to the present invention.

FIG. 2 is a schematic sectional view of a coating apparatus of the present invention.

FIG. 3 is a perspective view of an annular circular amount regulating type coating apparatus according to the present invention.

FIG. 4 is a schematic sectional view of a coating apparatus according to a preferred embodiment of the present invention.

FIG. 5 is a schematic sectional view of a coating apparatus according to another preferred embodiment of the present invention.

[Explanation of symbols]

 1A, 1B Cylindrical base material 2, 2A Coating liquid 3, 32 Coating device 4, 42 Hopper coating surface 5, 51, 52 Coating liquid tank 6-1, 6-2 Liquid feed pump 6-1 ', 6-2' Liquid feed pipe 6A, 6A 'Coating liquid supply section 7, 72 Coating liquid distribution chamber 8, 82 Coating liquid distribution slit 10 Constituent layer A 11 Constituent layer B

Claims (9)

[Claims] Claims: 1. A cylindrical base material having a cylindrical axis aligned and stacked,
While vertically pushing up from the bottom, on the outer peripheral surface of the substrate,
An electrophotographic photoreceptor obtained by applying the coating liquid sent from the coating liquid tank by the liquid sending means to the photoreceptor constituting layer A on the base material and further applying another constituent layer B adjacent thereto.
The reference length of the interface between the constituent layers A and B is 0.2.
An electrophotographic photoreceptor, wherein the surface roughness Rz1 at 5 mm is 0.05 to 0.5 μm, and the surface roughness Rz2 at the interface at a reference length of 2.5 mm is 2.0 μm or less. 2. The electrophotographic photoreceptor according to claim 1, wherein the device used for the coating is a circular amount control type coating device. 3. The electrophotographic photosensitive member according to claim 2, wherein said circular amount-regulating type coating device is a slide hopper type coating device. 4. The electrophotographic photoreceptor according to claim 1, wherein the photoreceptor constituting layer A is CTL, and the constituting layer B is OCL. 5. A stack in which the cylindrical axes of the cylindrical substrates are aligned.
An electrophotographic method in which a coating solution is continuously applied on the outer peripheral surface of the base material while being vertically pushed upward from the bottom, and a photoreceptor constituent layer A is further applied thereon, and another adjacent constituent layer B is further applied thereon. In the method for manufacturing a photoreceptor, the surface roughness Rz1 of the interface between the constituent layer A and the constituent layer B at a reference length of 0.25 mm is 0.05 to 0.5 μm, and the reference length is 2.5 mm A method for producing an electrophotographic photoreceptor, wherein the coating is performed such that the surface roughness Rz2 of the boundary surface is 2.0 μm or less. 6. The method according to claim 5, wherein said coating device is a circular amount control type coating device. 7. The method for producing an electrophotographic photoreceptor according to claim 6, wherein said circular amount-regulating type coating device is a slide hopper type coating device. 8. The method according to claim 6, wherein the coating is performed by a simultaneous multi-layer coating method using the circular amount-regulating type coating apparatus.
The method for producing the electrophotographic photosensitive member according to the above. 9. The method for producing an electrophotographic photoreceptor according to claim 6, wherein the coating is performed by a sequential coating method using the circular amount control type coating apparatus.