JP2007183485A - Method and apparatus for manufacturing photoreceptor, and the photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To remove a thickness part H formed on the edge on the opening side of an object to be coated by using a solvent tank, specially, to reduce such failures that a solvent film formed on the edge on the opening side bursts and the splashes of the solvent scatter in many directions. <P>SOLUTION: The photoreceptor manufacturing method includes a process of immersing the edge of the conductive base with a photoreceptor layer formed on the outer peripheral surface thereof in the solvent, a process of pulling up the conductive base from the solvent, and a process of reducing the internal pressure of the conductive base, after the conductive base is separated from the solvent level at the pull-up process. On the pull-up process, the solvent film formed on the edge of the conductive base is sucked into the inside of the conductive base. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member manufacturing method and a photosensitive member manufacturing apparatus used in an image forming apparatus such as a copying machine, a printer, or a facsimile, and a photosensitive member. It is.

The photoreceptor used in the image forming apparatus has a large number of conductive substrates immersed in a coating tank filled with an organic photoreceptor coating solution from the viewpoints of excellent productivity, low cost, and easy operation. Then, it is manufactured by a dip coating method in which it is pulled at a constant speed or an arbitrarily changed speed. According to this dip coating method, there arises a problem that a thick portion H is formed at the end portion of the conductive substrate A as shown in FIG. In order to solve this problem, a method of removing the thick portion has been proposed. As one of the methods, there is a method of immersing an object to be coated once in a solvent tank and dissolving the coating layer. However, this method raises the following problems.
That is, as shown in FIG. 6 (a), a photosensitive layer is formed on the outer peripheral surface, and the upper end side of a cylindrical conductive substrate having an open lower end side is held by a chucking device, and this is suspended to conduct electricity. When the lower end portion of the conductive substrate A is immersed in the solvent bath B as shown in FIG. 6 (b) from above the solvent bath B to dissolve the thick portion, the conductive substrate A is pulled up. As shown in (c), a solvent film C may be formed on the end face of the conductive substrate A. The solvent film C has a thick part thickness, a solvent liquid viscosity and surface tension, end face finishing accuracy, end face wettability to a solvent, a conductive substrate pulling speed, time passage, solvent evaporation, Probably due to the cause. Then, when the solvent film C repels due to the elapse of time and the evaporation of the solvent, the droplet D of the solvent film is scattered in all directions as shown in FIG. 6 (d). As described above, when the solvent film C bounces and the droplets D adhere to the surface of the photoreceptor layer, the electrical characteristics, mechanical characteristics, and image characteristics of the photoreceptor are deteriorated, which greatly affects image formation.

Further, as a method for preventing the thick portion H from being formed at the end portion of the conductive substrate A, for example, the pulling rate is slowed at the final stage of the dip coating, so that the film thickness of the upper and lower portions of the conductive substrate is uniform. There is a way to make it. However, this method makes it difficult to ensure a steady state in mass production, and unevenness appears in the vertical direction of the coating film. Further, there is a method of once stopping at the final stage of the dip coating, but in this method, the thickness of the coating film at the lower end tends to be thin.
Patent Document 1 discloses a method of removing an excess coating film attached to a conductive substrate having a photoreceptor layer formed on the outer peripheral surface. Patent Document 2 discloses a resin contained in a solvent by immersing an end portion of a conductive substrate having an organic photoreceptor layer formed on the outer peripheral surface in a soluble solvent tank. Discloses a technique for covering the end face of the substrate with a film by the above, thereby preventing the separation of residues. And the process which wipes off a thick part with a braid | blade is provided.
Japanese Examined Patent Publication No. 4-73778 JP 2000-305287 A

  In view of the above problems, the present invention is to remove the thick portion H formed at the opening side end of the object to be coated using a solvent tank. Is immersed in the solvent solution from the end on the opening side, and then pulled up from the solvent solution, a solvent film is formed on the end on the opening side due to the surface tension of the solvent solution. Provides a method and an apparatus for producing an electrophotographic photosensitive member capable of reducing the solvent film and preventing splashes of solvent liquid from being scattered in multiple directions and preventing the scattered solvent liquid from adhering to an adjacent coated object. Is. The present invention also provides an electrophotographic photosensitive member manufactured by the manufacturing method and manufacturing apparatus.

The method for producing a photoconductor of the present invention includes a step of holding an upper end side of a cylindrical conductive substrate having a photoconductor layer formed on an outer peripheral surface and having an open lower end side in a chucking device, and a lower end side of the conductive substrate. In the solvent solution, in the step of pulling up the conductive substrate from the solvent solution, and in the pulling step, the interior of the conductive substrate is depressurized after the conductive substrate is separated from the solvent liquid surface. A process.
Moreover, it is desirable that the time for starting the decompression is 0.5 to 30 seconds after the conductive substrate is separated from the solvent liquid.
The solvent film formed on the end surface of the conductive substrate may be sucked into the conductive substrate by the pulling process.
The present invention also provides a photoconductor produced by the above method for producing a photoconductor.

According to another aspect of the present invention, there is provided an apparatus for manufacturing a photoconductor, in which a photoconductor layer is formed on an outer peripheral surface, and a chuck for holding an upper end side of one or more cylindrical conductive substrates having an open lower end side. A king device, a solvent tank that immerses the lower end of one or more conductive substrates held by the chucking device in a solvent solution, and a drive that immerses or pulls up the one or more conductive substrates in the solvent tank A mechanism, a decompression device that depressurizes the inside of the one or more conductive substrates, and when the drive mechanism pulls the one or more conductive substrates out of the solvent tank, the one or more conductive substrates are And a controller that controls the decompression device so as to decompress the interior of the one or more conductive substrates after leaving the liquid surface of the solvent.
Moreover, it is preferable that the present invention includes an adjustment unit that adjusts the resin concentration in the solvent liquid of the solvent tank to a predetermined value or less.
The solvent stored in the solvent tank may be the same type as the solvent contained in the photoreceptor layer formed on the outer peripheral surface of the conductive substrate.
Furthermore, the photoconductor manufacturing apparatus according to the present invention is the photoconductor manufacturing apparatus according to claim 5, further comprising a coating tank for applying a photoconductor layer to an outer peripheral surface of one or more conductive substrates, and the one or more electrophotographic substrates. It is desirable to provide an air vent for removing the air inside the one or more conductive substrates while the conductive substrate is immersed in the coating tank, and to connect the pressure reducing device and the air vent to a valve.
The present invention also provides a photoconductor manufactured by the above-described photoconductor manufacturing apparatus.

According to the present invention, in the step of pulling up the conductive substrate immersed in the solvent tank, the inside of the conductive substrate is decompressed after the conductive substrate is separated from the solvent liquid surface, so that the solvent formed on the end surface of the conductive substrate The film can be bounced inside the conductive substrate to prevent the solvent film splash D from adhering to the photoreceptor layer.
Since the time for starting the decompression is 0.5 seconds or more after the conductive substrate is separated from the solvent liquid, the solvent film formed on the end surface of the conductive substrate without sucking the solvent in the solvent tank is used. Can be surely broken and inhaled. Further, since it is within 30 seconds, it is before the solvent film is dried, and the solvent film can be reliably broken and the splash can be sucked. Further, the stringing phenomenon of the solvent film can be prevented.

In the present invention, when the conductive substrate is lifted from the solvent tank, the pressure reducing device is controlled so that the inside of the conductive substrate is depressurized after the conductive substrate is separated from the solvent liquid surface. In the case of producing a photosensitive substrate, a photoreceptor having a uniform photoreceptor layer can be produced.
Further, since the resin concentration in the solvent liquid in the solvent tank is adjusted to a predetermined value or less, the quality change between before and after the lot can be eliminated.
Furthermore, the present invention includes an air vent for removing the air inside the conductive substrate while the conductive substrate is immersed in the coating tank, and the air vent and the pressure reducing device are connected to the valve. it can.

As shown in FIG. 1, the photoconductor of the present invention dissolves the first step of forming a photoconductor layer on the outer peripheral surface of the electroconductive substrate and the thick portion formed at the end of the electroconductive substrate. It is manufactured by the second step of treating the solvent film formed on the end surface of the conductive substrate and the third step of removing the thick portion formed on the end portion of the conductive substrate. Here, the present invention is characterized by the second step.
As shown in FIG. 2, the manufacturing apparatus used in the first step includes a coating tank 2 filled with a coating solution 1 and a lifting device that drives a conductive substrate 4 held by a chucking device 3 by a motor 5. 6. The conductive substrate 4 is lowered by the lifting device 6 and immersed in the coating liquid 1. After the immersion, the conductive substrate 4 is lifted by the lifting device 6 and pulled up from the coating tank 2. The coating film is formed on the outer peripheral surface of the conductive substrate 4 by the above operation.
When the conductive substrate 4 is immersed in the coating tank 2, the solvent in the coating solution that has entered from the lower end opening of the conductive substrate 4 is vaporized to increase the gas volume. It pops out into the coating liquid as bubbles from the lower end opening. In particular, when the conductive substrate 4 is deeply immersed in the coating tank 2, bubbles are likely to jump out. When the bubbles that have popped out rise along the outer peripheral surface of the conductive substrate, the surface of the coating solution is disturbed and uneven coating occurs in the coating layer. In order to prevent bubbles generated in this way, an air vent 13 is provided for extracting air inside the conductive substrate in order to prevent an increase in air pressure inside the conductive substrate. The air vent 13 is configured by connecting an open / close valve to a pipe communicating with the inside of the conductive substrate. By opening the open / close valve, the air inside the conductive substrate can be extracted.

The photoreceptor manufacturing apparatus includes an overflow tank 7 and an auxiliary tank 8 because the coating liquid 1 overflows from the coating tank 2 when the conductive substrate 4 is completely immersed. The coating liquid 1 recovered by the overflow tank 7 and the auxiliary tank 8 is stirred by the stirring device 9, and the coating liquid is appropriately added from the additional coating liquid tank 10 for storing the coating liquid, and its components are adjusted to be constant, Further, after the foreign matter is filtered by the filter 11, it is returned to the coating tank 2 by the pump 12.
The conductive substrate end processing apparatus used in the second step has the same configuration as that shown in FIG. 2, and stores a solvent liquid instead of the coating liquid 1 stored in the coating tank 2. Moreover, since the coating tank 2 immerses only the edge part of an electroconductive base | substrate, the solvent tank which has the depth which can immerse an edge part is used. Other configurations and operations are the same. Details will be described later with reference to FIG.

The photoconductor of the present invention is a photoconductor using an organic material, and the organic photoconductor is formed by a stacked type (function separation type). The multilayer photoconductor includes a charge generation layer (CGL) including a charge generation material (CGM) that generates charge carriers upon light irradiation, and a charge transport material (CTM) that receives and transports the charge carriers generated in the charge generation layer. It consists of a charge transport layer (CTL) as a main component. An undercoat layer (UCL) may be provided between the conductive substrate and the photosensitive layer.
In another embodiment, the photoreceptor of the present invention is a single layer type. A single layer type photoreceptor is formed by a photosensitive layer in which a charge generation material is dispersed in a binder, or a photosensitive layer in which a charge generation material is dispersed in the form of pigment particles in a binder containing a charge transport material. The The single-layer type photoconductor is a positively charged photoconductor with less ozone, and is composed of a single photoconductive layer. Therefore, the single-layer type photoconductor has features such as a lower manufacturing cost and a higher yield than the stacked type.

The materials used for the photoreceptor will be described below.
First, as the conductive substrate, for example, aluminum, copper, brass, zinc, nickel, stainless steel, chromium, molybdenum, vanadium, indium, titanium, gold or platinum, or an alloy thereof, an aluminum alloy, or tin oxide is used. Can be used. Alternatively, film-like polyester deposited or coated with gold, indium oxide, or the like, paper or metal, plastic or paper containing conductive particles, or plastic containing a conductive polymer can be used. These materials are used after being processed into a cylindrical shape, a columnar shape or a sheet shape. The conductive substrate of the present invention is used by forming aluminum in a cylindrical shape.

Next, the material of the multilayer photoconductor will be described.
In forming the photosensitive layer, an undercoat layer is provided between the substrate and the charge generation layer. Undercoat layer covers conductive substrate scratches and irregularities, prevents pinholes, prevents deterioration of chargeability during repeated use, improves charging characteristics under low temperature and low humidity environment, improves charging properties, substrate To prevent unnecessary charge injection from the photosensitive layer or to improve the adhesion of the photosensitive layer.

  As the undercoat layer, resins such as polyamide, copolymer nylon, polyvinyl alcohol, polyurethane, polyester, epoxy, phenol resin, casein, cellulose, or gelatin can be used. Particularly, alcohol-soluble copolymer nylon is frequently used, and the conductive substrate of the present invention is also used as an undercoat layer. If necessary, zinc oxide, titanium oxide, tin oxide, indium oxide, silica, antimony oxide, etc. for setting the volume resistivity of the undercoat layer and improving the repeated aging characteristics under low temperature and low humidity environment These inorganic pigments are dispersed and contained using a dispersing machine such as a ball mill, a dyno mill and an ultrasonic oscillator.

To form the undercoat layer, first, the resin and pigment described above are dispersed in water or various organic solvents to prepare an undercoat layer coating solution. In particular, water, methanol, ethanol or butanol alone, mixed solvents such as water and alcohols or two or more alcohols, or chlorinated solvents such as dichloroethane, chloroform, trichloroethane, trichloroethylene or perchloroethylene and alcohols These mixed solvents are preferred. The adjusted coating solution is applied onto the outer peripheral surface of the substrate by the dip coating method using the manufacturing apparatus shown in FIG. 2 and dried. The drying conditions of the coating film are set at 40 ° C. to 130 ° C. and in the range of 10 minutes to 2 hours so that no solvent remains.
The ratio of the inorganic pigment in the undercoat layer is suitably in the range of 30 to 95% by weight. The pulling speed when forming the undercoat layer is set according to the viscosity and concentration of the undercoat layer coating solution and the thickness of the coating layer, but is preferably 0.1 to 5.0 cm / s. The immersion speed is preferably 1.2 to 10 times the pulling speed. The thickness of the undercoat layer is set in the range of about 0.1 to 5 μm.

The charge generation layer contains as a main component a charge generation material that generates charges when irradiated with light, and contains a binder, a plasticizer, a sensitizer, and the like as necessary.
Examples of the charge generating material include perylene pigments such as peryleneimide and perylene anhydride, polycyclic quinone pigments such as quinacridone and anthraquinone, phthalocyanine pigments such as metal or metal-free phthalocyanine and halogenated metal-free phthalocyanine, and squalium dyes. , An azurenium dye, a thiapyrylium dye, or an azo having a carbazole skeleton, a styryl stilbene skeleton, a triphenylamine skeleton, a dibenzothiophene skeleton, an oxadiazole skeleton, a fluorenone skeleton, a bis-stilbene skeleton, a distyryl oxadiazole skeleton, or a distyryl carbazole skeleton Pigments can be used. Examples of the pigment having particularly high charge generation ability include a metal-free phthalocyanine pigment, an oxotitanyl phthalocyanine pigment, a bisazo pigment containing a fluorene ring and a fluorenone ring, a bisazo pigment made of an aromatic amine, and a trisazo pigment.

Examples of the binder for the charge generation layer include melamine resin, epoxy resin, silicon resin, polyurethane resin, acrylic resin, vinyl chloride-vinyl acetate copolymer resin, polycarbonate resin, phenoxy resin, polyvinyl butyral resin, polyarylate resin, There is a polyamide resin or a polyester resin.
The charge generation layer coating solution is prepared by dissolving the above binder in a solvent and dispersing the charge generation material. Examples of the solvent include ketones such as acetone, methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, ethers such as tetrahydrofuran and dioxane, aromatic hydrocarbons such as benzene, toluene and xylene, N, N- Aprotic polar solvents such as dimethylformamide and dimethyl sulfoxide can be used.

As with the undercoat layer, the charge generation layer is prepared by preparing a charge generation layer coating solution and applying the coating solution onto the substrate on which the undercoat layer is formed by the dip coating method using the manufacturing apparatus shown in FIG. And dried to form. The drying conditions of the coating film are set at 40 ° C. to 130 ° C. and in the range of 10 minutes to 2 hours so that no solvent remains.
The ratio of the charge generation material in the charge generation layer is set in the range of 30 to 90% by weight. The pulling rate in forming the charge generation layer is set according to the viscosity and concentration of the charge generation layer coating solution and the thickness of the coating layer, but is preferably 0.1 to 5.0 cm / s. The immersion speed is preferably 1.2 to 10 times the pulling speed. The thickness of the charge generation layer is set in the range of 0.05 to 5 μm, preferably in the range of 0.1 to 2.5 μm.

The charge transport layer is provided on the charge generation layer. A charge transport material having the ability to accept and transport the charge generated by the charge generation material, a binder, and a yuzu skin prevention leveling agent are essential components, and a plasticizer, a sensitizer, and the like are included as necessary.
Examples of the charge transport material include poly-N-vinylcarbazole and derivatives thereof, poly-γ-carbazolylethyl glutamate and derivatives thereof, pyrene-formaldehyde condensates and derivatives thereof, polyvinylpyrene, polyvinylphenanthrene, oxazole derivatives, oxadi Azole derivatives, imidazole derivatives, 9- (p-diethylaminostyryl) anthracene, 1,1-bis (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline, pyrazoline derivatives, phenylhydrazones, hydrazone derivatives, triphenyl Electron-donating substances such as amine compounds, triphenylmethane compounds, stilbene compounds, azine compounds having a 3-methyl-2-benzothiazoline ring, Non derivatives, dibenzothiophene derivatives, indenothiophene derivatives, phenanthrenequinone derivatives, indenopyridine derivatives, thioxanthone derivatives, benzo [c] cinnoline derivatives, phenazine oxide derivatives, tetracyanoethylene, tetracyanoquinodimethane, bromanyl, chloranil And electron-accepting substances such as benzoquinone.

The binder for the charge transport layer may be any one that is compatible with the charge transport material, such as polycarbonate and copolymer polycarbonate, polyarylate, polyvinyl butyral, polyamide, polyester, polyketone, epoxy resin, polyurethane, polyvinyl ketone. , Polystyrene, polyacrylamide, phenol resin, phenoxy resin, polysulfone resin and copolymer resins thereof. These are used individually or in mixture of 2 or more types. In particular, polystyrene, polycarbonate, and copolymerized polycarbonate, polyarylate, and polyester are preferable because they have a volume resistivity of 10 ¹³ Ω or more and are excellent in film formability and potential characteristics.

The charge transport layer coating solution is prepared by dissolving the above binder in a solvent and dissolving the charge transport material. Solvents that dissolve the binder and charge transport material include, for example, alcohols such as methanol and ethanol, ketones such as acetone, methyl ethyl ketone and cyclohexanone, ethers such as ethyl ether and tetrahydrofuran, fats such as chloroform, dichloroethane and dichloromethane. Group aromatic hydrocarbons, aromatic hydrocarbons such as benzene, chlorobenzene and toluene. Tetrahydrofuran is particularly desirable.
Similarly to the undercoat layer and the charge generation layer, the charge transport layer is prepared by adjusting the charge transport layer coating solution and using the manufacturing apparatus shown in FIG. It is formed on a substrate on which a layer has been formed and dried. The drying conditions of the coating film are set at 40 ° C. to 130 ° C. and in the range of 10 minutes to 2 hours so that no solvent remains.
The ratio of the charge transport material in the charge transport layer is preferably in the range of 30 to 80% by weight. The pulling speed when forming the charge transport layer is set according to the viscosity and concentration of the charge transport layer coating solution and the thickness of the coating layer, but is preferably 0.1 to 5.0 cm / s. The immersion speed is preferably 1.2 to 10 times the pulling speed. The thickness of the charge transport layer is preferably in the range of 10 to 50 μm, particularly preferably in the range of 15 to 40 μm.

Each process as described above is performed by sequentially arranging a coating tank containing the coating liquid for the undercoat layer, a coating tank containing the coating liquid for the charge generation layer, and a coating tank containing the coating liquid for the charge transport layer. The chucking device 3 that has been chucked is sequentially moved, the connection to each lifting device 6 is switched, and dipping, lifting, and drying are repeated in each coating tank. By the above first step, a photoreceptor layer is formed on the outer peripheral surface of the conductive substrate.
Since the photosensitive layer is applied by a dip coating method and dried in a state where the conductive substrate is suspended, a thick portion H is formed at the end of the conductive substrate A as shown in FIG. The thickness of the thick portion H is determined by the viscosity and drying characteristics of each coating solution for forming the undercoat layer, the charge generation layer, and the charge transport layer, the drying conditions, and the like. The present invention is characterized by a process prior to the third step of removing the thick portion, that is, the second step, in order to make the thickness of the photoreceptor layer uniform.
Therefore, in the second step of the present invention, the end portion of the conductive substrate is immersed in a solvent tank, the thick portion is dissolved, and the solvent film C formed on the end surface of the conductive substrate A is processed. The film thickness of the photoreceptor layer is prevented from becoming non-uniform.

The manufacturing apparatus used in the second step is basically similar to the apparatus shown in FIG. 2, but will be described again. Here, an apparatus capable of simultaneously manufacturing a plurality of conductive substrates will be described.
As shown in FIG. 3, the manufacturing apparatus of the present invention includes a solvent tank 22 filled with a solvent liquid 21 and a lifting device 26 that drives a conductive base 24 held by a chucking device 23 by a motor 25. The elevating device 26 includes a male screw portion 27, a bearing 28 of the male screw portion 27, a gear train 29 that connects the motor 25 and the male screw portion 27, a screw portion 30 that is screwed into the male screw portion 27, and a female screw portion. And a holding member 31 fixed to 30. Then, a support body 32 is attached to the holding member 31, and a plurality of chucking devices 23 are attached to the support body 32. Although four are shown in FIG. 3, in the embodiment, 10 to 50, more preferably 30 to 40, conductive substrates having a diameter of 1 cm to 5 cm, more preferably 2 cm to 4 cm are attached. At this time, the interval between the conductive substrates is set such that a blade for removing the thick portion at the end of the conductive substrate can be inserted in the third step. Specifically, it is about 7 cm. Desirably, the interval is 6 to 8 cm.
In this invention, the solvent tank 22 should just be the depth which can immerse the thick part formed in the edge part of the electroconductive base | substrate 24. FIG. The thickness and length of the thick part is determined by the viscosity, drying characteristics, and drying conditions of each coating solution used to form the undercoat layer, charge generation layer, and charge transport layer. To have a depth of. Alternatively, a sufficiently deep solvent tank 22 is prepared, and the raising and lowering of the elevating device 6a is controlled so that the thick part formed at the end of the conductive substrate is immersed in the solvent tank 22. In the embodiment, it is 1 cm to 10 cm, preferably 2 cm to 5 cm.

  The manufacturing apparatus of the present invention includes an auxiliary tank 35 connected by an overflow tank 33 and a reflux pipe 34 because the solvent liquid 21 overflows from the solvent tank 22 when the conductive substrate is immersed. The solvent liquid 21 recovered by the overflow tank 33 is stirred by the stirring device 36 in the auxiliary tank 35. The auxiliary tank 35 is provided with an additional solvent tank 37 for storing the solvent liquid 21, and the flow rate is adjusted by a valve 38 to keep the resin concentration of the solvent liquid 21 in the auxiliary tank 35 constant. By keeping the resin concentration constant, the strength of the solvent film formed on the end face of the conductive substrate is kept below a certain level, and the pressure is reduced and reliably sucked into the conductive substrate. The auxiliary tank 35 is provided with a supply pipe 39 connected to the solvent tank 22. The supply pipe 39 includes a pump 40, a valve 41, a filter 42, and a valve 43 in the middle thereof. The filter 42 removes the resin component of the photoreceptor layer dissolved in the solvent solution 21.

Further, in the present invention, an intake pipe 44 that penetrates the chucking device 23 and reaches the inside of the conductive base 24 is attached. The chucking device 23 includes a balloon chuck, an O-ring chuck, and a mechanical chuck. In order to pass through the intake pipe 44, a balloon chuck is suitable. A flexible pipe is suitable for the intake pipe 44 because the conductive substrate 24 is raised and lowered by the lifting device 26. The intake pipe 44 is connected to a suction means 45 such as a suction pump. This suction means constitutes a decompression device. The suction force by the suction means 45 is such that the solvent film formed on the end face of the conductive substrate 24 is sucked into the inside of the conductive substrate. Therefore, it is determined according to the weight of the solvent film formed on the end face of the conductive substrate and the weight of the splash formed by the solvent film. More specifically, the weight of the solvent film formed on the end face of the conductive substrate is determined by the product of the film thickness of the solvent film, the film area, and the specific gravity of the solvent. The weight of the splash is determined by the viscosity of the solvent film. If the suction force is too weak, splashes generated when the solvent film bounces cannot be sucked into the conductive substrate 24. If the suction force is too strong, the solvent liquid 21 in the solvent tank 22 may be sucked. In the embodiment, in the case of a conductive substrate having a diameter of 3 cm, a single suction force is about 3 to 5 times the weight of the solvent film. (However, when a plurality of suctions are performed, the presence or absence of a solvent film generated at the lower end of the substrate is present, so the suction force needs to be 20 to 40 times the weight of the solvent film.)
The suction means 45 can also be used as the air vent 13 in the first step. That is, a branching valve 14 is provided between the air vent 13 and the conductive substrate, and is connected to the suction means 45 through the branching valve 14. And when operating the suction means 45, it switches to the suction means 45 by the branch valve 14.
Alternatively, the air vent 13 may be constituted by the suction means 45. In this case, in the first step, the pressure is reduced to such an extent that the air inside the conductive substrate is removed. In the second step, when a film of the solvent solution is formed on the end face of the conductive substrate, the pressure is reduced to such an extent that the coating solution film is repelled inside the conductive substrate. In the first step, when the suction force of the suction means 45 is increased, the coating liquid is sucked up, so it is necessary to control the suction force so as not to suck up the coating liquid. Further, in the first step, when a film of the coating liquid is formed on the end face of the conductive substrate when the suction is performed with the same suction force as that in the second step and then pulled up, the coating liquid film is formed on the conductive substrate. Can be inhaled inside.

Further, in the present invention, the timing of reducing the air pressure inside the conductive substrate is after the conductive substrate 24 is pulled up from the solvent tank 22, but in short, before the solvent film C formed on the end surface of the conductive substrate 24 is repelled. It is. In the embodiment, the range is 0.5 to 30 seconds after pulling, and more preferably 0.5 to 5 seconds. If the depressurization start time is too early, the solvent liquid in the solvent tank is sucked into the conductive substrate. If the start time of decompression is too late, it will be after the solvent film has bounced and the initial effect of the present invention cannot be obtained. Further, since the solvent film is dried and hardened, the solvent film cannot be bounced. In particular, when a plurality of conductive substrates are dipped or pulled up at the same time, it is necessary to set the depressurization start timing so that the last conductive substrate is separated from the solvent surface.
FIG. 4 shows a block diagram of the suction device. The suction device includes a vacuum pump 51, and the vacuum pump 51 exhausts the vacuum tank 52. The vacuum tank 52 is connected to a vacuum regulator 54 via a solvent-resistant filter 53, and further connected to a plurality of conductive substrates 24 through a chucking device 23 via an electromagnetic valve 55 and a suction amount adjusting valve 56. The electromagnetic valve 55 is connected to the control unit 61 and controlled by the sequencer 62. In this embodiment, the control unit 61 is configured by a personal computer. The control unit 61 controls the raising / lowering timing and the raising / lowering speed of the lifting device 26 and also controls the opening / closing timing and the opening / closing size of the electromagnetic valve 55 according to the operation of the lifting device 26. Thereby, the pressure reduction timing and the magnitude of pressure reduction inside the conductive base 24 are controlled.

  The solvent stored in the solvent tank 22 is selected according to the material of the thick part formed at the end of the conductive substrate. The thickened portion includes an undercoat layer, a charge generation layer, and a charge transport layer, but the thickness of the undercoat layer is in the range of about 0.1 to 5 μm, and the thickness of the charge generation layer is 0.05. Since the thickness of the charge transport layer is in the range of 10 to 50 μm, the material of the thick portion is substantially the charge transport layer. Therefore, it is appropriate to use the same type of solvent as the solvent for the charge transport layer coating solution. That is, alcohols such as methanol and ethanol, ketones such as acetone, methyl ethyl ketone and cyclohexanone, ethers such as ethyl ether and tetrahydrofuran, aliphatic halogen hydrocarbons such as chloroform, dichloroethane and dichloromethane, and aromatics such as benzene, chlorobenzene and toluene It is a group hydrocarbon. Tetrahydrofuran is particularly desirable. And the quantity of resin contained in a solvent is adjusted to 1-3 wt% with respect to a solvent.

The second step of the present invention is performed as follows using the apparatus shown in FIG.
The manufacturing apparatus shown in FIG. 3 raises the elevating device 26 and attaches the conductive substrate 24 to each of the plurality of chucking devices 23. The solvent tank 22 is filled with the solvent liquid 21. Then, the conductive substrate 24 is lowered by the lifting device 26 and immersed in the solvent liquid 21 in the solvent tank 22. The dipping time is determined by the size of the thick part formed at the end of the conductive substrate and the meltability of the thick part. It is immersed until the thick part melts in the solvent and the film thickness of the photoreceptor layer becomes uniform.
Thereafter, the conductive substrate 24 is raised by the lifting device 26. After the conductive substrate 24 is separated from the solvent liquid level in the solvent tank 22, the pressure reducing device is operated to reduce the air pressure inside the conductive substrate. The timing for starting the decompression and the degree of the suction force are as described above. Thus, after the conductive substrate 24 is separated from the solvent liquid surface of the solvent tank 22, the pressure is reduced, so that the solvent film C is repelled inside the conductive substrate A as shown in FIG. Can be attached to the side. As a result, the solvent film does not adhere to the photoreceptor layer, and the solvent in the solvent tank does not adhere to the photoreceptor layer.

As described above, in the second step, the thick part is dissolved in the immersion solvent tank, and the solvent film formed on the end surface of the conductive substrate is lifted inward by the suction means when pulled up from the solvent tank. Let Therefore, the problem that the solvent film can be spilled to the outside of the conductive substrate during the next process is reduced. Moreover, since the time of a lower end surface processing process (performed after all the coating layers are formed) can be shortened by reducing the thickness part, work efficiency can be improved.
Since the photoconductor layer cannot be made to have a completely uniform film thickness by the method in the second step, the thick portion after dissolution and the edge of the inner surface of the conductive substrate by the suction method in the second step are obtained in the third step. The photosensitive film is formed to have a uniform thickness by further removing the stringing generated at the portion and the coating film adhering to the inner surface of the end portion. Therefore, in the third step, the blade is applied to the stringing generated at the end of the inner surface of the conductive substrate, the coating film adhering to the inner surface of the end, or the thick part that cannot be removed in the second step. A uniform film thickness is obtained by scraping the coating film. As a result, the photoreceptor can be finished.

Process drawing of the manufacturing method of this invention is shown. The block diagram of a photoreceptor layer solution coating apparatus is shown. The block diagram of a pre-processing apparatus is shown. The block diagram of a decompression device is shown. An explanatory view of a pretreatment process is shown. The figure explaining formation of a solvent film is shown. The figure explaining the thick part formed in the edge part of an electroconductive base | substrate is shown.

Explanation of symbols

21 Solvent tank 22 Solvent 23 Chucking device 24 Conductive substrate 26 Lifting device 45 Suction means

Claims (9)

A step of holding the upper end side of a cylindrical conductive substrate having a photoreceptor layer formed on the outer peripheral surface and having an open lower end side in a chucking device;
Immersing the lower end side of the conductive substrate in a solvent solution;
Pulling up the conductive substrate from the solvent solution;
In the pulling step, after the conductive substrate is separated from the solvent liquid surface, the step of decompressing the inside of the conductive substrate;
A process for producing a photoreceptor, comprising:   2. The method of manufacturing a photoreceptor according to claim 1, wherein the timing of starting the pressure reduction is 0.5 to 30 seconds after the conductive substrate is separated from the solvent solution.   3. The method of manufacturing a photosensitive member according to claim 1, wherein a solvent film formed on an end face of the conductive substrate is sucked into the conductive substrate by the decompression step.   A photoconductor produced by the method for producing a photoconductor according to claim 1. A chucking device that holds the upper end side of one or a plurality of cylindrical conductive substrates having a photoreceptor layer formed on the outer peripheral surface and having an open lower end side;
A solvent bath for immersing the lower end of one or more conductive substrates held in the chucking device in a solvent solution;
A drive mechanism for immersing or pulling up the one or more conductive substrates in the solvent tank;
A decompression device for decompressing the interior of the one or more conductive substrates;
When the driving mechanism pulls up the one or more conductive substrates from the solvent tank, after the one or more conductive substrates are separated from the solvent liquid surface, the inside of the one or more conductive substrates is moved. A control unit for controlling the decompression device to decompress,
An apparatus for producing a photoreceptor, comprising:   6. The photoconductor manufacturing apparatus according to claim 5, further comprising an adjusting unit that adjusts the resin concentration in the solvent solution of the solvent tank to a predetermined value or less.   7. The photoconductor manufacturing apparatus according to claim 5, wherein the solvent stored in the solvent tank is the same type as the solvent contained in the photoconductor layer formed on the outer peripheral surface of the conductive substrate.   The apparatus for manufacturing a photoreceptor according to claim 5 further includes a coating tank for applying a photosensitive layer to an outer peripheral surface of one or a plurality of conductive substrates, and dipping the one or more conductive substrates in the coating tank. And an air vent part for venting air inside the one or more conductive substrates, wherein the pressure reducing device and the air vent part are connected to a valve.   A photoconductor manufactured using the photoconductor manufacturing apparatus according to claim 5.