JPH0689033A - Method for manufacturing electrophotographic photoreceptor - Google Patents

Abstract

PURPOSE:To prevent the generation of any defect in the case when washing by water is carried out as a cleaning process. CONSTITUTION:In a production of an electrophotographic sensitive body in which a photosensitive layer is formed on an electrical conductive base body 1 made of aluminum, the electrical conductive base body 1 is dipped in water containing surfactants (first and second washing liqs. 11 and 12) before formation of the photosensitive layer on the electrical conductive base body, and then, the electrical conductive base body 1 is washed if being rubbed with a cleaning component (not shown in the figure) in a water (a third washing liq. 31).

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 photosensitive member used in copying machines, printers and the like.

[0002]

2. Description of the Related Art Generally, an electrophotographic photosensitive member is one in which a photosensitive layer is formed on a drum-shaped conductive substrate. This drum-shaped conductive substrate is shaped by cutting a cylindrical aluminum surface and performing mirror surface processing or impact molding. Mineral oil such as kerosene naphtha is generally used during cutting or impact molding. This is for cooling the heat generated during cutting or impact molding, preventing wear of the lubricating tool, and improving the surface accuracy of the substrate surface after cutting or impact molding. Mist of cutting oil, dust in the air, chips, etc. adhere to the surface of the substrate during mirror finishing or impact molding. Therefore, after cleaning the surface of the substrate to remove them, a charge transport layer comprising a charge generating substance such as a condensed polycyclic pigment and an azo pigment, a resin binder, an additive such as an antioxidant and the like is sequentially applied, It is laminated and dried to form a photosensitive layer.

The charge-generating layer and the charge-transporting layer are formed by immersing the drum-shaped conductive substrate in a coating method containing the above-mentioned substances constituting the charge-generating layer and the charge-transporting layer by a known method. Formed on the surface. The dip coating method performed here is not particularly limited and known methods can be used. For example, the methods disclosed in JP-A-49-130736, JP-A-57-5047 and JP-A-59-46171 can be used. Can be mentioned.

In the dip coating method, if the surface of the conductive substrate is insufficiently cleaned, oil, dust and the like remain on the surface, which causes coating defects such as cissing and stains during coating. Such defects generated on the electrophotographic photosensitive member appear as unevenness of black and white halftone images in a copy image of a copying machine using this photosensitive member, and adversely affect image quality.

As the method for cleaning the surface of the substrate, dipping cleaning in which the substrate is generally immersed and / or immersed under the action of ultrasonic waves in an organic solvent that is heated, or when the substrate is immersed in a solvent or Examples include contact cleaning in which the substrate is physically rubbed with a brush or sponge while showering the solvent with a solvent, jet cleaning in which the solvent is jetted from the slit onto the substrate surface, and vapor cleaning in which the substrate is inserted into solvent vapor. Or the combination cleans the substrate surface.

As the solvent used here, methyl chloride, ethylene chloride, 1.1.1-trichloroethane, trichloroethylene, perchlorethylene,
Chlorine-based solvent such as CFC-112, CFC-112, CFC-113 and other fluorine-based solvent, mixed solvent of the fluorine solvent and methanol, methylene chloride, etc., benzene, toluene, methanol, ethanol, isopropyl alcohol, petroleum hydrocarbons and the like. A mixture of These solvents include those that are flammable and ignitable, those that have a low permissible concentration because they are harmful to the human body, and those that have a poor cleaning ability. The most commonly used solvent is 1 ．
1.1-Trichloroethane.

As the electroconductive substrate of the electrophotographic photoreceptor,
Examples thereof include a drum-shaped substrate or a thin film sheet made of a metal such as aluminum, copper, brass, nickel or stainless steel, or a film obtained by vapor deposition of aluminum, tin alloy, indium oxide or the like on a polyester film, paper or a drum-shaped substrate made of a metal film. Aluminum is the most common in terms of low price, ease of processing, strength and weight.

Aluminum having a high degree of purity is used from the viewpoint of ease of processing and adhesion to a photosensitive layer, but it has the property of being highly reactive and soft, and this tendency tends to occur as the purity of aluminum increases. Becomes stronger.

Therefore, when cleaning the surface of such a conductive substrate made of high-purity aluminum, cleaning with an organic solvent is generally performed in consideration of the reactivity and softness of the surface of the conductive substrate. Target.

However, although 1.1.1-trichloroethane has advantages such as high cleaning ability and easy handling, it is considered to be one of the substances that cause global warming and ozone layer depletion. With CFCs, the reduction has been decided all over the world, and the development of an alternative cleaning agent for 1.1.1-trichloroethane and an alternative cleaning method has been earnestly desired.

In recent years, as an alternative cleaning method, water cleaning has been studied in which the surface of the substrate is cleaned with city water, pure water, ion-exchanged water, or water containing a nonionic surfactant and / or anionic surfactant. .

[0012] In this method, oil and dust adhering to the surface of a substrate are washed with water containing a surface active agent which has been micellar under the action of ultrasonic waves, and then the surface adhering agent adhering to the surface is washed away by rinsing with water. Is the way.

[0013]

However, if ultrasonic waves are applied for the purpose of enhancing the cleaning effect and water cleaning is performed,
Since water has a higher surface tension and ultrasonic waves act stronger than organic solvents, when aluminum is used as the conductive substrate, pinhole defects are likely to occur in this conductive substrate due to long-term water washing, and Corrosion occurs when it reacts with water, and when a photosensitive layer is formed on it, there arises a problem that the photosensitive layer becomes a defect such as a stain or coating missing. On the other hand, washing with water without applying ultrasonic waves lowers the washing ability, and not only does it take a long time to wash but also insufficient washing results in stains on the conductive substrate after washing, and the coating of the photoconductor. After that, it is easy for the coating to be left uncoated.

Further, if the contact cleaning is carried out in the water containing the surfactant, a large amount of bubbles are generated in order to operate the cleaning member or the conductive substrate, and the cleaning efficiency is lowered.

In view of the above points, the present invention uses a conductive substrate made of aluminum for an electrophotographic photosensitive member, and even when water washing is performed as the cleaning method, pinhole defects, stains, and photosensitive layer of the conductive substrate are caused. The present invention provides a method for producing an electrophotographic photosensitive member which does not cause defects such as coating loss.

[0016]

The present invention is a method for producing an electrophotographic photosensitive member in which a photosensitive layer is formed on a conductive substrate made of aluminum, before forming a photosensitive layer on the conductive substrate. It is characterized by including a step of immersing the conductive substrate in water containing a surfactant and a step of rubbing the conductive substrate immersed in the water containing a surfactant with a cleaning member in water.

[0017]

[Function] When the conductive substrate is immersed in water containing a surfactant,
The lipophilic group of the surfactant acts on the cutting oil and the like adhering to the conductive substrate, so that the cutting oil and the like are easily removed from the conductive substrate into water.

When the conductive substrate in this state is contact-cleaned by rubbing it in water with a cleaning member, cutting oil, dust, and chips can be sufficiently removed in a short time with a weak contact pressure. It is possible to prevent corrosion, damage, pinhole defects, and the like, and it is possible to suppress the generation of spots and coating spots when the photosensitive layer is formed on the photosensitive layer.

Further, since contact cleaning is not carried out in the surfactant, no bubbles are generated and cleaning efficiency is not lowered.

[0020]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

(Embodiment 1) FIG. 1 is a schematic view of a cleaning apparatus used in this embodiment. The drum-shaped conductive substrate 1 made of aluminum that has been cut in the same manner as the conventional one is the clamper 2
Is held by the cylinder 8 and can be moved along the rail 3 and can be moved up and down by the cylinder 8. Further, the clamper 2 is supported by the shaft 7, and the rotation of the motor 5 is transmitted to the shaft 7 via the belt 6 to rotate the conductive substrate 1.

The first cleaning tank 10 is filled with a cleaning liquid 11 of pure water in which a surfactant is dissolved, and the cleaning liquid is heated to 40 to 60 ° C., here 50 ° C., by a heater (not shown). There is. An overflow pipe 15 is adapted to be discharged when the cleaning liquid 11 has a predetermined amount or more.

Like the first cleaning tank 10, the second cleaning tank 20 is filled with a cleaning solution 21 of pure water in which a surfactant is dissolved, and the cleaning solution is heated by a heater (not shown) 40
It is heated to -60 ° C, here 50 ° C. Reference numeral 25 is a pipe for supplying the cleaning liquid 21. When the second cleaning tank 20 is filled with the cleaning liquid 21, it overflows into the first cleaning tank 10. The conductive substrate 1 moves along the rail 3, descends by the cylinder 8 to be immersed in the first cleaning tank 10, and then rises again to move along the rail 3. Similarly, it is immersed in the second cleaning tank 20.

The third cleaning tank 30 to the fifth cleaning tank 50 are rinsing tanks for rinsing with pure water at 25 ° C. Pure water enters the fifth cleaning tank 50 through the pipe 55, and overflows with the fourth cleaning tank 40 and the third cleaning tank 30 in order. Reference numeral 35 is a waste liquid pipe for collecting water in the third cleaning tank 30 and sending it to a regenerator (not shown). The cleaning liquid in each cleaning tank is supplied from the respective pipes 12, 22, 32, 42, 52 to the pumps 13, 2
Circulate through 3, 33, 43, 53, filter 14,
Dust, chips and the like are removed by 24, 34, 44 and 54. As shown in FIG. 2, the third cleaning tank 30 has
The cleaning member 61 is provided. The cleaning member 61 is provided so as to be movable left and right by a cylinder 62, and is rotated by the rotation of the motor 7. Third cleaning tank 3
When the conductive substrate 1 is lowered to 0 by the cylinder 8 and immersed therein, the conductive substrate 1 is rotated at a speed of 1000 rpm by the rotation of the motor 5. On the other hand, the cleaning brush moves to a position where it comes into contact with the conductive substrate 1 with a predetermined pressure by the cylinder 62, and rotates in the opposite direction to the conductive substrate 1. In this way, the dust, chips, cutting oil and surfactant adhering to the surface of the conductive substrate 1 are removed.

Here, the pH of the cleaning liquid in the first cleaning tank is 6.
It is 0 to 9.0, preferably 6.5 to 8.0. When the pH of the cleaning liquid is controlled to 6.0 to 9.0, the formation of hydroxides, oxides, and hydrates that corrode the surface of the aluminum substrate is suppressed, and physical properties such as wettability due to the reaction product are suppressed. Does not occur, it is possible to suppress the occurrence of coating defects such as cissing, spots, and coating loss during coating. Further, the burden on the cleaning liquid wastewater treatment facility and the like is reduced, and the facility cost and the wastewater treatment cost can be reduced.

As the surfactants used in the cleaning liquids 11 and 12, nonionic surfactants and / or anionic surfactants that do not corrode the substrate can be used. Specifically, polyoxyethylene alkylphenyl ether, Nonionic surfactants of polyoxyethylene, polyoxypropylene, block copolymer type and nonylphenol polyoxyethyl ether, and sulfates of alkylbenzenes, higher alcohols, α-olefins, anions of silicates, carbonates or phosphates A surfactant can be used. Among them, as the surfactant that forms a cleaning solution having a pH of 6.0 to 9.0, PORACULIN 690 manufactured by Tanaka Import Group Co., Ltd. and T- manufactured by Henkel Hakusui Co., Ltd.
180, FM-10 and Lyomix L manufactured by Lion Corporation, CA01 manufactured by Chemix Corporation, and Kao Corporation
The clean-through 750L manufactured by K.K.

The concentration of the surfactant in the cleaning liquids 11 and 12 is 0.5 to 30%, preferably 4 to 15%. In this example, a 5% pure water solution of Lyomix-H (manufactured by Lion Corporation) was used.

As the cleaning aid (builder), an inorganic builder such as sodium carbonate, sodium tripolyphosphate, sodium pyrophosphate, sodium silicate or sodium sulfate, or an organic builder such as carboxymethyl cellulose, methyl cellulose or organic amine is used as the cleaning liquid 11 or 1
2 may be added.

The electroconductive substrate 1 is immersed and washed in the cleaning tanks 10 and 20 in this order for 0.5 to 10 minutes, preferably 1.5 to 5 minutes. Here, each was soaked for 2 minutes.
The shape of the cleaning member 61 in the third cleaning tank 30 is preferably a brush shape, and the material is preferably an organic synthetic resin such as nylon or polypropylene, which does not damage the cleaning property and the conductive substrate 1. Therefore, the diameter of one brush is 2.0 mm or less, and the number of rotations of the cleaning brush is 10 to 5
00rpn, preferably 50 to 150 rpn, and the contact pressure between the conductive substrate 1 and the cleaning brush is 1.5 to 3.0 kg / c.
m ^{2 is} preferably 2 kg / cm ² . In this embodiment, the cleaning member is a brush made of nylon, the rotation speed is 50 rpn, and the contact pressure between the conductive substrate 1 and the cleaning member is 2.5 kg / cm ^2.
I went there.

The cleaned drum-shaped conductive substrate 1 is dried by blowing clean air at 80 ° C. in a clean booth 60 maintained at a clean degree of 100.

A photosensitive layer is formed on the surface of the drum-shaped conductive substrate 1 by a known method. For example, a charge generation layer is formed on the surface of the washed conductive substrate 1 by a dip coating method, a link method coating method, or a spray coating method, and then,
A charge transport layer is formed on the charge generation layer by a dip coating method or a spray coating method.

The charge generation layer contains a charge generation material which generates charges upon irradiation with light as a main component, and if necessary, known binders, plasticizers and sensitizers, and has a film thickness of 1.0 μm or less. Thus, it is coated on the conductive substrate 1. Examples of the charge generation material include perylene pigments, polycyclic quinone pigments, phthalocyanine pigments, metal phthalocyanine pigments, squarylium dyes, azulenium dyes, thiapyrylium dyes, and carbazole skeletons, styrylstilbene skeletons, triphenylamine skeletons, dibenzothiophene. Examples include azo pigments having a skeleton oxadiazole skeleton, a fluoronone skeleton, a bisstilbene skeleton, a distyloxadiazole skeleton, or a distilcarbazole skeleton.

Here, the following liquid A was applied by dip coating to a film thickness of 0.5 μm and dried at 80 ° C. for 10 minutes to form a charge generation layer.

The charge transport layer contains as an essential component a charge transport material and a binder capable of receiving the charge generated by the charge generating material and transporting the charge, and if necessary, known leveling agents, plasticizers and additives. Contains a sensitizer, etc., and has a dry film thickness of 5 to 70 μm.
It is coated on the charge generation layer so as to be m.

As the charge transport material, poly-N-vinylcarbazole and its derivative, poly-γ-carbazolylethylglutamate and its derivative, pyrene-formaldehyde condensate and its derivative, polyvinylpyrene, polyvinylphenatolenoxazole derivative, Oxodiazole derivative, imidazole derivative, 9- (p-diethylaminostyryl) anthracene, 1,1-bis (4-
Electron donors such as dibenzylaminophenyl) propane, styrylanthracene, stilpyrazoline, phenylhydrazones, and hydrazone derivatives, or fluorenone derivatives, dibenzothiophene derivatives, indenothiophene derivatives, phenanthrenequinone derivatives, indenopyridine derivatives, thioxanthone derivatives Examples thereof include electron-accepting substances such as benzo (c) cinnoline derivative, phenazine oxide derivative, tetracyanoethylene, tetracyanoquinodimethane, promannyl, chloranil, and benzoquinone. The binder constituting the charge transport layer may be one that is compatible with the charge transport material, for example, polycarbonate, polyvinyl butyral, polyamide,
Examples thereof include polyester, polyketone, epoxy resin, polyurethane, polyvinyl ketone, polystyrene, polyacrylamide, phenol resin, and phenoxy resin.

Here, the following liquid B was applied by dip coating to a film thickness of 20 μm and dried at 75 ° C. for 1 hour to form a charge transport layer.

Liquid A: 2 parts by weight of dibromoanthanthrone, 2 parts by weight of butyral resin (S-REC BM-2 manufactured by Sekisui Chemical Co., Ltd.),
A solution obtained by dispersing 230 parts by weight of cyclohexanone in a ball mill for 8 hours.

Liquid B Hydrazone type charge transport material (ABP manufactured by Nippon Kayaku Co., Ltd.)
H) 1 part by weight, a solution obtained by dissolving 1 part by weight of a polycarbonate resin (Panlite L-1250 manufactured by Teijin Chemicals Ltd.) in 8 parts by weight of dichloroethane.

30 electrophotographic photoconductors formed by changing the electric conductivity of the above-mentioned cleaning liquids 25, 35, 45 were mounted on a copying machine (SF-8100 manufactured by Sharp Corporation) to make a copy, and the image was evaluated. went. The results are shown in Table 1. Here, the evaluation was performed on 30 photoconductors based on the number of spots (black spots on the image) of 0.5 mm or more and coating defects (white spots on the image). (Example 2) First and second cleaning tanks 1 in Example 1
Instead of using a 5% pure water solution of Lyomics-H (manufactured by Lion Corporation) as a cleaning solution for Nos. 0 and 20, Polarclean 690 (manufactured by Tanaka Import Group Co., Ltd.) was used, and the rotation speed of the cleaning member 61 was 50 rpn. , The contact pressure between the conductive substrate 1 and the cleaning member 61 is 2.5 kg / cm ² , instead of 145 rpn and 1.5 kg / cm ² , respectively.
Other than that, an electrophotographic photosensitive member was prepared in the same manner as in Example 1, and the results of examining the occurrence state of defects are shown in Table 1.

(Embodiment 3) As a cleaning liquid for the first and second cleaning tanks 10 and 20 in the first embodiment, Lyomics-
CW-5520 (manufactured by Dai-Ichi Kogyo Seiyaku Co., Ltd.) was used instead of using 5% pure water solution of H (manufactured by Lion Co., Ltd.), a nylon brush was used as the cleaning member 61, a rotation speed was 50 rpn, and conductivity was used. The contact pressure between the conductive substrate 1 and the cleaning member 61 is 2.5 kg / cm ² , instead of using a polypropylene brush, the rotation speed, the conductive substrate 1 and the cleaning member 6 are used.
1, the contact pressure with 100rpn, 2.0kg /
An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that cm ² was used, and the occurrence of defects was examined. The results are shown in Table 1.

(Comparative Example 1) Instead of washing with water in Example 1, the cut conductive substrate 1 was subjected to 1.
Ultrasonication using 1.1-trichloroethane, warm bath cleaning treatment for 30 seconds, cold bath cleaning treatment with 1.1.1-trichloroethane at 20 ° C. for 30 seconds, and 1.1.1-trichloroethane. After performing the steam cleaning treatment of 30 seconds for 30 seconds, it was left for 20 minutes in a clean booth with a clean degree of 100. A photosensitive layer was formed on the surface of the conductive substrate 1 in the same manner as in Example 1 to obtain an electrophotographic photosensitive member.
In the same manner as in Example 1, the book was examined for the occurrence of defects. The results are shown in Table 1.

(Comparative Example 2) A 5% pure aqueous solution of Lyomix-H (manufactured by Lion Corporation) was used as a cleaning liquid in a cleaning tank, immersed and cleaned for 2 minutes under ultrasonic action, and then rinsed with pure water. Immersion cleaning was performed in a bath for 2 minutes under ultrasonic action. The cleanliness of the washed drum-shaped conductive substrate 1 is 10
In a clean booth kept at 0, 80 ° C. clean air was blown to dry. A photosensitive layer was formed on the surface of the conductive substrate 1 in the same manner as in Example 1 to obtain an electrophotographic photosensitive member, and 30 electrophotographic photosensitive members were examined for the occurrence of defects in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 3 An electrophotographic photosensitive member was prepared by forming a photosensitive layer on the surface of the conductive substrate 1 which was not subjected to the washing treatment in Example 1 in the same manner as in Example 1, and 30 electrophotographic photosensitive members were prepared. In the same manner as in Example 1, the occurrence status of defects was examined.
The results are shown in Table 1.

[0044]

[Table 1]

As is clear from Examples 1 to 3 and Comparative Examples 1 to 3, according to the method of the present invention, the generation of defects such as spots and coating omissions is the same as in the case of cleaning with water, even when cleaning with water. Can be held down.

[0046]

According to the present invention, even when a conductive substrate made of aluminum is used for an electrophotographic photosensitive member and water cleaning is performed as the cleaning method, defects such as stains and coating missing of the photosensitive layer are prevented. be able to. In addition, since no organic solvent is used, it does not adversely affect the environment.

[Brief description of drawings]

FIG. 1 is a schematic view of a cleaning device used in an embodiment of the present invention.

FIG. 2 is a partial schematic view of a cleaning device according to an embodiment of the present invention.

[Explanation of symbols]

 1 Conductive Substrate 10 First Cleaning Tank 20 Second Cleaning Tank 30 Third Cleaning Tank 61 Cleaning Member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masayuki Sakamoto 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Ryuhiro Morita 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Kazuyuki Arai 22-22 Nagaike-cho, Abeno-ku, Osaka City, Osaka Prefecture Inside Sharp Corporation

Claims (1)

[Claims] 1. In a method for producing an electrophotographic photosensitive member comprising a conductive substrate made of aluminum and a photosensitive layer formed thereon, the conductive substrate is treated with a surfactant before the photosensitive layer is formed on the conductive substrate. And a step of rubbing the electroconductive substrate immersed in the surfactant-containing water with a cleaning member in water, the method for producing an electrophotographic photosensitive member.