JP2001356504A - Method and device for manufacturing organic electrophotographic photoreceptor and organic electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improved method and a device for manufacturing an organic electrophotographic photoreceptor to be used for an image forming device such as a copying machine, printer, facsimile or the like by which method and device unnecessary part at an end of a cylindrical conductive substrate is removed from a photosensitive layer deposited on the substrate by the method of dip coating and to provide an organic electrophotographic photoreceptor manufactured by the method and the device. SOLUTION: The solvent for the treatment to remove the unnecessary photosensitive layer on the photoreceptor substrate contains at least glycol ethers. The solvent is a mixture of at least (A) glycol ethers and (B) water or non halogen organic solvent, or the solvent is a mixture of at least two kinds of ethers and a mixture of (A) glycol ethers and (C) cyclic ethers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing an organic electrophotographic photosensitive member used in an image forming apparatus such as a copying machine, a printer and a facsimile, and an organic electrophotographic photosensitive member to be manufactured. The present invention relates to an improved manufacturing method for removing unnecessary portions at the ends of a photosensitive layer formed on a cylindrical conductive substrate by a dip coating method.

[0002]

2. Description of the Related Art In recent years, materials used for electrophotographic photosensitive members have been developed from inorganic materials represented by zinc oxide, cadmium sulfide, amorphous selenium, amorphous silicon and the like, which have been conventionally used due to the progress of development. Organic conductive materials (OPCs) have been widely used. Electrophotographic photoreceptors using organic photoconductive materials have some problems in sensitivity, durability, environmental stability, etc., but compared with inorganic materials in terms of toxicity, cost, flexibility in material design, etc. There are many advantages.

Accordingly, various sensitizing methods have been proposed from the vigorous studies of various companies. Conventional organic electrophotographic photoreceptors include those having a single-layer photoconductive layer and those having a laminated photoconductive layer. Among them, a material that generates charge carriers when irradiated with light (hereinafter referred to as “charge generating material: CGM”) ) (Hereinafter referred to as “charge generation layer: CGL”) and CG
A layer mainly composed of a substance (hereinafter, referred to as “charge transporting substance: CTM”) that receives and transports the charge carriers generated in L (hereinafter, referred to as “charge transporting substance: CTM”). Since the photoreceptor (hereinafter referred to as “functionally separated photoreceptor”) exhibits excellent sensitizing properties, it has occupied most of the organic photoreceptors currently in practical use. Further, it is expected to become the mainstream of photoconductors in the future due to the improvement in durability in recent years.

[0004] Further, on the substrate to improve chargeability, prevent unnecessary charge injection from the conductive substrate, cover defects on the conductive substrate, prevent generation of pinholes, and improve the adhesiveness of the photosensitive layer. By providing an undercoat layer (hereinafter referred to as “UCL”), durability has been improved.

[0005] These photosensitive layers are prepared by dissolving or dispersing an organic photoconductive material for constituting each layer together with a binder resin in an organic solvent to prepare a photosensitive material-containing coating solution. It is manufactured by sequentially applying a liquid on a conductive substrate and drying.

[0006] As a coating method of the organic electrophotographic photosensitive member,
Examples include a spray method, a bar coating method, a roll coating method, a blade method, a ring method, and a dip coating method. Here, in the dip coating method, a (cylindrical) conductive substrate is immersed in a coating tank filled with a coating solution (containing a photosensitive material), and then is pulled up at a constant speed or an arbitrarily changed speed to thereby raise the photosensitive layer. It is a method of forming. This dip coating method is relatively simple and is excellent in terms of productivity and cost, and is therefore often used in the production of electrophotographic photosensitive members.

FIG. 1 shows an example of an apparatus used for dip coating. The coating tank 4 contains a coating liquid 5 containing a photoreceptor material. The cylindrical conductive substrate 1, the upper end of which is hermetically sealed by the chucking device 8, is immersed in the coating solution 5 in the coating tank 4. In immersion, the chucking device 8 is lowered by the elevator 2 having the motor 3, and the substrate 1 is immersed in the coating liquid 5. After sufficiently immersing, the chucking device 8 is raised by the elevator 2. By controlling and confirming the rotation amount of the motor 3, the elevator 2 can immerse the base 1 in the coating tank 4 to a desired depth. In this example, the base 1 moves up and down, but the coating may be performed by moving the coating tank 4 up and down. Upon immersion,
The liquid overflowing from the coating tank 4 is collected in the auxiliary tank 7 and adjusted and stirred using the stirrer 11 so that the viscosity of the coating liquid becomes constant. After returning to the coating tank 4 by 6 and filling the coating tank 4 with the coating liquid 5 again, the next coating is performed.

In the dip coating method described above, since the entire conductive substrate 1 is immersed in the coating liquid 5, the coating liquid is always applied to the lower end of the substrate, and a coating film having an uneven film thickness is formed. Also,
Part of the coating liquid also penetrates into the inside of the substrate, and an unnecessary coating film is formed. FIG. 2 is a cross-sectional view of a main part showing the lower end of the photoconductor drum after application, and extra coating films (photosensitive layers) 20a, 20b, and 20c are formed on the lower end of the photoconductor drum 21.

Unnecessary coating films (20b, 20c) on the inner and lower end portions of the base cannot be inserted when the flange for driving the drum is fitted, or even if fitted, the deflection accuracy of the entire drum deteriorates. Cause. In addition, the excess coating film (20a) at the lower end is thicker than a predetermined film thickness. For example, when the photosensitive layer is heated and dried as it is, bubbles are generated by a large amount of solvent trapped inside the coating film,
Causes image defects. Further, since the thickness of the photosensitive layer is not uniform, the edge portion of the cleaning blade for cleaning unnecessary toner on the photosensitive layer after development-transfer does not accurately contact the photosensitive layer, resulting in poor cleaning. Toner fall,
Filming and film failure may occur. Also,
Generally, at both ends of the developing tank, there are provided rollers for positioning with respect to a drum called a DSD color, which stably develops by making accurate contact with both ends of the drum. As a result, problems such as blurring of the image, falling of the toner without adhering to the drum, and failure to obtain a beautiful image occur.

In order to remove the coating film of the photosensitive layer formed on the lower end of the photosensitive drum as described above, the coating film has been hitherto disclosed, for example, in Japanese Patent Publication No. 4-73778. In order to dissolve and remove the excess coating by dipping the end of the formed photoreceptor drum in a removal tank containing a solvent in which the coating is soluble, and to further enhance the removability of the coating, A method in which a plate (blade) or scraper is brought into contact with the coating film to be removed together with the solvent and wiped off (Japanese Patent Publication No. 4-4).
A method of wiping using various organic solvents is generally used.

[0011]

The organic solvents used in the conventional wiping treatment include chlorine (halogen) solvents such as dichloromethane, dichloroethane and chloroform, acetone, methyl ethyl ketone, tetrahydrofuran, cyclohexanone, toluene, alcohol, and the like. N-methyl-
And pyrrolidone. Particularly, chlorine-based solvents such as dichloromethane have been frequently used from the viewpoint of solubility.

However, many chlorine (halogen) organic solvents may be harmful (carcinogenic) to the human body,
Particularly in recent years, use restrictions or prohibition measures have been taken in view of global environmental problems and adverse effects on the human body. In addition, acetone, methyl ethyl ketone, tetrahydrofuran, cyclohexanone, toluene, alcohol, etc. have a low flash point (for example, tetrahydrofuran is -17 ° C), and there is a risk of easily catching fire or explosion. And the amount of use (storage amount) must be limited. In addition, since the evaporation rate is relatively high, evaporation occurs during the process, and the amount of spontaneous evaporation outside the effective use increases, resulting in high costs. N-methyl-pyrrolidone has a high flash point (95 ° C.) and is relatively safe under the Fire Service Law, but the boiling point (202 ° C.) is too high, so that the solvent attached to the wiped portion does not dry. Will remain. For this reason, it is carried over to the next process, which is a factor that deteriorates the yield. Also, because the solubility is too high, it may dissolve to the part that does not need to be removed, or if it leaks out of the wiping device, it may corrode even the resin parts used in the device itself, etc. There is a problem of.

Further, as a result of diligent studies, glycol ethers (for example, 3-methyl-3-
Methoxy-1-butanol, 3-methyl-3-methoxy-butyl acetate, etc.) were found to be relatively good. These wiping solvents have a flash point (~ 70 ° C)
And the boiling point (〜180 ° C.) is lower than that of N-methyl-pyrrolidone. However, the solubility and drying (evaporation) properties are insufficient for stably producing an organic electrophotographic photosensitive member at a high yield rate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an organic electrophotography using a solvent for safely and efficiently wiping an unnecessary coating film formed on a lower end portion of a photosensitive body. An object of the present invention is to provide a method and an apparatus for manufacturing a photoconductor, and a photoconductor.

[0015]

SUMMARY OF THE INVENTION According to the present invention, there is provided a method comprising:
A process solvent for removing an unnecessary photosensitive layer on a photoreceptor substrate, comprising at least glycol ethers.

According to the present invention, the non-uniform and unnecessary coating on the end of the conductive substrate formed by the dip coating method can be safely and efficiently wiped without adversely affecting the global environment and workers. It is possible to process. Accordingly, when a drum driving flange or the like is fitted, it is possible to easily insert the flange and to satisfy the runout accuracy of the entire drum. Also,
Due to the excess coating film at the lower end part thicker than the predetermined film thickness, no bubbles are generated during heating and drying, and the cleaning blade also accurately contacts the photoconductor surface,
It is unlikely to cause poor cleaning, toner drop, filming, and film loss. Further, since the positioning between the developing tank and the drum can be performed with high precision, there is no problem such as blurring of an image or dropping of toner adhered to the drum.

As described above, according to the present invention, it is possible to provide a high-quality organic electrophotographic photosensitive member.

A second aspect of the present invention is an organic electrophotographic photoreceptor wherein the processing solvent is a mixture of at least (A) a glycol ether and (B) water or a non-halogen organic solvent. It is a manufacturing method.

According to the second aspect of the present invention, the treatment solvent containing glycol ethers is mixed with water or a non-halogen organic solvent, so that the end of the conductive substrate formed by the dip coating method can be used. Uneven and unnecessary coating films can be safely and efficiently wiped without adverse effects on the global environment and workers. In particular, by mixing water with glycol ethers, the flash point of the wiping solvent can be further increased, and the risk of explosion and the like can be reduced. In particular, by using a mixed system with a non-halogen organic solvent, it is possible to provide a safe production method which does not adversely affect the global environment and workers. Furthermore, since it is possible to control the solubility of the photosensitive layer and the like and the evaporation rate of the wiping solvent, it is possible to dissolve the portion that does not need to be removed, or if the wiping processing solvent leaks from the wiping device, It is possible to perform high quality wiping without corroding resin parts used in the apparatus itself, suppressing consumption and increasing costs.

A third aspect of the present invention is an organic electrophotographic photoreceptor, wherein the processing solvent for removing an unnecessary photosensitive layer on the photoreceptor substrate is a mixed system of at least two or more ethers. It is a manufacturing method of.

According to the third aspect of the present invention, since a halogen-based organic solvent is not used as a processing solvent for removing an unnecessary photosensitive layer on the photosensitive body, an end of the conductive base formed by the dip coating method is used. It is possible to safely and efficiently wipe off non-uniform and unnecessary coating films without adverse effects on the global environment and workers. Accordingly, when the flange for driving the drum is fitted, it can be easily inserted and the deflection accuracy of the entire drum can be satisfied. In addition, there is no generation of air bubbles during heating and drying caused by an excess coating film at the lower end portion which is thicker than a predetermined thickness, and the cleaning blade accurately contacts the photoconductor surface, so that cleaning failure, It is unlikely to cause toner drop, filming, and film loss. In addition, since the positioning between the developing tank and the drum is performed with high accuracy, there is no problem such as blurring of an image or dropping of toner without adhering to the drum.

Further, by using a mixed system of two or more ethers as the treatment solvent, the flash point of the wiping solvent can be controlled, and the danger of explosion and the like can be reduced. In addition, since the solubility to the photosensitive layer etc. can be controlled, even if it does not need to be removed, it can be dissolved or if it leaks out of the wiping device, it can be used for the resin parts used in the device itself. No trouble such as corrosion occurs. Furthermore, since the evaporation rate of the wiping solvent can be controlled, the consumption due to spontaneous evaporation other than processing can be suppressed and the cost can be reduced. In addition, the processing solvent does not remain at the edge of the substrate, and high-quality wiping can be performed. Becomes

According to a fourth aspect of the present invention, the processing solvent is a mixture of at least a glycol ether (A) and a cyclic ether (C). It is a manufacturing method of.

According to the fourth aspect of the present invention, since the wiping solvent is a mixed system of at least a glycol ether and a cyclic ether, the end of the conductive substrate formed by the dip coating method is not uniform, and Unnecessary coating films can be safely and efficiently wiped off without adverse effects on the global environment and workers. Furthermore, the flash point, solubility,
Control of the evaporation rate and the like can be easily performed.

Next, claim 5 is that the processing solvent (A) is 3-methyl-3-methoxy-1-butanol or
The method according to any one of claims 1 to 4, wherein the organic electrophotographic photosensitive member is 3-methyl-3-methoxy-butyl acetate.

Next, a sixth aspect of the present invention is the method for producing an organic electrophotographic photosensitive member according to the fourth aspect, wherein the processing solvent (C) is tetrahydrofuran or dioxolane.

According to the combination of the fifth and sixth aspects of the present invention, the non-uniform and unnecessary coating film on the end of the conductive substrate formed by the dip coating method is transferred to the global environment and workers. Safe and efficient wiping and removal can be performed most easily and with high accuracy without adverse effects. Further, the flash point, solubility, evaporation rate, and the like of the wiping solvent can be most easily and optimally controlled.

In a preferred embodiment, the mixing ratio (A) :( C) of the processing solvent (A) and the processing solvent (B) is 1: 5 to 2: 1.
7. The method according to claim 4, wherein the volume ratio is (volume ratio).

According to the seventh aspect of the invention, by setting the mixing ratio within the above range, the flash point, solubility,
It is possible to control the evaporation rate and the like to optimal conditions in the process, and it is possible to provide a method for manufacturing a high-quality photoconductor.

Further, the resin used for the photosensitive layer treated with the treatment solvent may be polycarbonate, a copolymer thereof, polyester, polyamide, copolymer nylon, polyarylate, polystyrene, polyvinyl alcohol, polyvinyl butyral, 8. The method according to claim 1, wherein the photosensitive material is at least one selected from the group consisting of a vinyl chloride-vinyl acetate resin, a phenoxy resin, a polyimide resin, and an epoxy resin. is there.

The organic solvent for wiping treatment according to the invention of claim 8 can easily dissolve the resin group often used in the above-mentioned organic electrophotographic photosensitive member, and efficiently produce a high-quality photosensitive member. It becomes possible.

In a ninth aspect of the present invention, the photosensitive layer is removed by providing a blade or a sponge-like wiping member in sliding contact with the solvent tank filled with the processing solvent. Item 10. A method for producing an organic electrophotographic photosensitive member according to Item 8.

According to the ninth aspect of the present invention, the blade or sponge-like wiping member is slid in contact with the wiping treatment solvent, so that an unnecessary coating film at the end of the photosensitive member base is provided.
In particular, the inside and lower end of the base can be efficiently and accurately wiped off.

According to a tenth aspect of the present invention, the photosensitive layer is removed by pressing the lower end surface of the cylindrical photosensitive body base against a cloth-like wiping member containing the processing solvent. A method for producing an organic electrophotographic photoreceptor according to claim 8.

According to the tenth aspect of the present invention, by pressing the cloth-like wiping member against the lower end face of the base together with the processing solvent, the unnecessary coating film particularly on the lower end face of the base is efficiently and accurately wiped. It is possible to remove it. In addition, since the non-uniform (thick) film thickness portion at the lower end can be made thinner by sucking it toward the member side, generation of bubbles after heating and drying can be prevented without completely wiping and removing the lower end. .

Next, an eleventh aspect is an apparatus for manufacturing an organic electrophotographic photosensitive member, wherein the processing solvent is used. According to the present invention, the non-uniform and unnecessary coating film on the end of the conductive substrate formed by the dip coating method has no adverse effects on the global environment and workers, and has a low risk of ignition explosion. It is possible to efficiently and accurately remove the wafer safely and without incurring unnecessary cost increase. This makes it possible to provide an apparatus for manufacturing a high-quality organic electrophotographic photosensitive member.

Next, an organic electrophotographic photoreceptor is characterized in that it is produced using the processing solvent.

According to the twelfth aspect of the present invention, the non-uniform and unnecessary coating on the end of the conductive substrate formed by the dip coating method can be used without causing adverse effects (carcinogenicity) on the global environment and workers. In addition, it is possible to efficiently and accurately remove and remove the risk of inflammable explosion and the like safely and without unnecessary cost increase. As a result, it is possible to supply a high-quality organic electrophotographic photoreceptor free of image defects and toner scattering and having a small deflection of the drum itself when a flange or the like is fitted, at a low cost.

Finally, an image forming apparatus according to a thirteenth aspect uses an organic electrophotographic photoreceptor manufactured using the processing solvent.

According to the thirteenth aspect, it is possible to provide an image forming apparatus which outputs a good image without image defects and toner scattering.

Next, generally used materials for an organic electrophotographic photosensitive member will be described. The photoreceptor material according to the present invention is not limited to the contents described below.

As the substrate, those having conductivity, for example, aluminum, copper, brass, zinc, nickel, stainless steel, chromium, molybdenum, vanadium, indium,
Metals and alloy materials such as titanium, gold and platinum can be used, and in addition, aluminum, aluminum alloy, tin oxide, polyester film on which gold or indium oxide is deposited or coated, paper and metal films, and conductive particles Plastics and papers, plastics containing a conductive polymer, and the like can be used. These materials are used after being processed into a cylindrical shape, a cylindrical shape, or a thin film sheet shape. Particularly, since the conductive substrate used in the present invention is applied by a dip coating method, the conductive substrate is preferably cylindrical.

Next, the structure of the laminated photoreceptor will be described. In the formation of the photosensitive layer, the conductive substrate and the charge generating layer may be covered for reasons such as covering the conductive substrate with scratches and irregularities, preventing deterioration of charging property when repeatedly used, and improving charging characteristics in a low-temperature / low-humidity environment. There may be a case where an undercoat layer is provided between the carrier and the charge transport layer.

As the material of the undercoat layer, polyamide, copolymerized nylon, polyvinyl alcohol, polyurethane, polyester, epoxy, phenolic resin, casein, cellulose, gelatin and the like have been conventionally known. Particularly, alcohol-soluble copolymerized nylon is known. Is often used.
These are treated with water and various organic solvents, especially water, methanol,
Ethanol, butanol alone, water / alcohols, mixed solvent of two or more alcohols, or mixed solvent of acetone, dioxolane, etc. and alcohols, or chlorinated solvent such as dichloroethane, chloroform, trichloroethane and alcohols It is dispersed in a mixed solvent with the same and is applied to the surface of the conductive substrate using, for example, the dip coating apparatus shown in FIG.

If necessary, particularly for the purpose of adjusting the volume resistivity of the undercoat layer and improving the repeated aging characteristics in a low-temperature / low-humidity environment, etc., zinc oxide, titanium oxide, tin oxide, indium oxide, silica It is known that inorganic pigments such as antimony oxide are dispersed and contained using a disperser such as a ball mill, a dyno mill, and an ultrasonic oscillator. The ratio of the inorganic pigment in the undercoat layer is preferably in the range of 30 to 95% by weight, and the coating is performed so that the film thickness is about 0.1 to 5 μm.

The charge generation layer contains, as a main component, a charge generation material that generates charges by light irradiation, and may contain a known binder resin, a plasticizer, and a sensitizer as needed. As the charge generating material, perylene imide, perylene anhydride and perylene pigment, quinacridone, polycyclic quinone pigment such as anthraquinone, metal and metal-free phthalocyanine, phthalocyanine pigment such as halogenated metal-free phthalocyanine, squarium dye , Azurenium dye, thiapyrylium dye, and azo having a carbazole skeleton, styrylstilbene skeleton, triphenylamine skeleton, dibenzothiophene skeleton, oxadiazole skeleton, fluorenone skeleton, bisstilbene skeleton, distyryloxadiazole skeleton or distyrylcarbazole skeleton Pigments and the like. Pigments having particularly high charge generating ability include metal-free phthalocyanine pigments, oxotitanyl phthalocyanine pigments, gallium (chloro) phthalocyanine pigments, mixed crystals of metal phthalocyanines and metal-free phthalocyanines, bisazo pigments containing a fluorene ring and a fluorenone ring, aromatic Examples thereof include bisazo pigments and trisazo pigments composed of an aromatic amine, and can provide a photosensitive member having high sensitivity.

As the binder resin, melamine resin,
Epoxy resin, silicone resin, polyurethane resin, acrylic resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, vinyl chloride-vinyl acetate-polyvinyl alcohol copolymer resin,
Polycarbonate resin, phenoxy resin, phenol resin, polyvinyl butyral resin, polyarylate resin,
Polyamide resins, polyester resins and the like, as solvents for dissolving these resins, acetone, methyl ethyl ketone, ketones such as cyclohexanone, ethyl acetate, esters such as butyl acetate, tetrahydrofuran, dioxane, dioxolan, dimethoxyethane and the like Ethers, aromatic hydrocarbons such as benzene, toluene and xylene, and aprotic polar solvents such as N, N-dimethylformamide and dimethylsulfoxide can be used.

Examples of the method for forming the charge generation layer include a method in which a compound is directly formed into a film by vacuum evaporation, and a method in which the compound is dispersed in a binder resin solution and applied to form a film. The method of mixing and dispersing the charge generating substance in the binder resin solution and the method of applying the same are the same as those of the undercoat layer. The ratio of the charge generation material in the charge generation layer is preferably in the range of 30 to 90% by weight. The thickness of the charge generation layer is 0.05 to 5 μm, preferably 0.1 to 5 μm.
2.5 μm.

The charge transporting layer provided on the charge generating layer has a charge transporting material capable of receiving and transporting charges generated by the charge generating material, a binder resin, and if necessary, a known plasticizer, Contains a sensitizer and the like. Examples of charge transport materials include poly-N-vinylcarbazole and its derivatives, poly-γ-carbazolylethylglutamate and its derivatives, pyrene-formaldehyde condensate and its derivatives, polyvinylpyrene, polyvinylphenanthrene, oxazole derivatives, oxadiazole Derivatives, imidazole derivatives, 9- (p-diethylaminostyryl) anthracene, 1,1-bis (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazolin, pyrazoline derivatives, phenylhydrazones, hydrazone derivatives, triphenyl Amine compounds,
Triphenylmethane compounds, stilbene compounds, 3
An electron donating substance such as an azine compound having a -methyl-2-benzothiazoline ring, or a fluorenone derivative, a dibenzothiophene derivative, an indenothiophene derivative,
Electron accepting substances such as phenanthrenequinone derivatives, indenopyridine derivatives, thioxanthone derivatives, benzo [c] cinnoline derivatives, phenazine oxide derivatives, tetracyanoethylene, tetracyanoquinodimethane, promanyl, chloranil, and benzoquinone. .

The binder resin constituting the charge transport layer includes:
Any material having compatibility with the charge transport material may be used, for example, polycarbonate and copolymerized polycarbonate,
Polyarylate, polyvinyl butyral, polyamide,
Examples include polyester, epoxy resin, polyurethane, polyketone, polyvinylketone, polystyrene, polyacrylamide, phenol resin, phenoxy resin, polysulfone resin and the like and copolymer resins thereof. These may be used alone or in combination of two or more. Above all, resins such as polystyrene, polycarbonate, copolycarbonate, polyarylate, and polyester have a volume resistivity of 10 ¹³ Ω or more and are excellent in film-forming properties and potential characteristics.

The solvent for dissolving these materials is
Alcohols such as methanol and ethanol, acetone,
Ketones such as methyl ethyl ketone and cyclohexanone,
Ethers such as ethyl ether, tetrahydrofuran, dioxane, and dioxolane, chloroform, dichloromethane, aliphatic hydrocarbons such as dichloroethane, halogen hydrocarbons,
Aromatic substances such as benzene, chlorobenzene, and toluene can be used.

The charge transport layer coating solution is prepared by dissolving a charge transport material in a binder resin solution, and the proportion of the transport material is preferably in the range of 30 to 80% by weight. The thickness of the charge transport layer is 10 to 50 μm, preferably 15 to 40 μm.
m.

These photosensitive layers are dried by using a dryer such as hot air or far-infrared ray after being coated and formed sequentially by the above-mentioned method, or each photosensitive layer is completed. Drying is preferably performed at 40 ° C. to 130 ° C. for about 10 minutes to 2 hours.

Further, the solvent used in the above-mentioned coating solution for each photosensitive layer is not limited to the above range, but the use of a non-chlorine (halogen) -based organic solvent makes it difficult for the global environment and workers. It is preferable in consideration of safety.

The binder resin used in each of the above-mentioned coating solutions for photosensitive layers is not limited to the above range, but in the present invention, polycarbonate and its copolymer,
It is preferably at least one selected from the group consisting of polyester, polyamide, copolymerized nylon, polyarylate, polystyrene, polyvinyl alcohol, polyvinyl butyral, vinyl chloride-vinyl acetate resin, phenoxy resin, polyimide resin, and epoxy resin. Further, the photosensitive layer of the electrophotographic photoreceptor contains one or more electron accepting substances or dyes for the purpose of improving sensitivity and suppressing increase in residual potential and fatigue upon repeated use. You may. Examples of the electron acceptor used herein include acid anhydrides such as succinic anhydride, maleic anhydride, phthalic anhydride, and 4-chloronaphthalic anhydride; cyano compounds such as tetracyanoethylene and terephthalmalondinitrile; Aldehydes such as nitrobenzaldehyde, anthraquinones such as anthraquinone and 1-nitroanthraquinone, and polycyclic or heterocyclic nitro compounds such as 2,4,7-trinitrofluorenone and 2,4,5,7-tetranitrofluorenone. It can be used as a chemical sensitizer.

As the dye, for example, an organic photoconductive compound such as a xanthene dye, a thiazine dye, a triphenylmethane dye, a quinoline pigment, and copper phthalocyanine can be used as the optical sensitizer.

The photosensitive layer may further contain a well-known plasticizer in order to improve moldability, flexibility, and mechanical strength. Examples of the plasticizer include dibasic acid esters, fatty acid esters, phosphoric acid esters, phthalic acid esters, chlorinated paraffins, and epoxy-type plasticizers. Also, if necessary, a leveling agent for preventing citron skin such as polysiloxane,
In order to improve durability, a phenolic compound, a hydroquinone-based compound, a tocopherol-based compound, an amine-based compound, or other oxidized fat inhibitor, an ultraviolet absorber, or the like may be contained.

Next, the constitution of the single-layer type photoreceptor is obtained by dispersing the above-mentioned CGM in the above-mentioned binder resin or the above-mentioned CT.
A photosensitive layer containing M in which CGM is dispersed in the form of pigment particles. The single-layer photoreceptor has the advantage of being a photoreceptor for a positively charged image forming apparatus that generates less ozone,
In addition, since only one photosensitive layer is to be applied, the manufacturing cost and the yield are better than those of the stacked type.

In any of the photoreceptor formulations and layer configurations, the coating liquid according to the present invention is prepared by a manufacturing apparatus represented by the dip coating apparatus shown in FIG. Particularly in the case of a coating apparatus for a pigment dispersion coating liquid, in order to stabilize the dispersibility of the coating liquid,
An unillustrated coating liquid dispersion device (typified by an ultrasonic generator) may be provided.

Next, an example of the configuration of the image forming apparatus will be described with reference to a schematic explanatory diagram. The image forming apparatus according to the present invention is not limited to the contents described below. FIG. 3 is a view showing a laser printer 60 equipped with an organic electrophotographic photosensitive member manufactured by the manufacturing method of the present invention. The laser printer 60 includes the photoconductor 21, the semiconductor laser 61, the rotating polygon mirror 62, the imaging lens 64, and the mirror 6.
5, corona charger 66, developing device 67, transfer paper cassette 6
8, sheet feeding roller 69, registration roller 70, transfer charger 71, separation charger 72, transport belt 73, fixing device 74,
It includes a paper discharge tray 75 and a cleaner 76.

The photoreceptor 21 is mounted on the laser printer 60 so as to be rotatable in the direction of arrow 77 in the figure by driving means (not shown). The laser beam 68 from the semiconductor laser 61 is applied to the photosensitive member 2 by the rotating polygon mirror 62.
One surface is repeatedly scanned in its longitudinal direction (main scanning direction). The imaging lens 64 has an f-θ characteristic, and reflects the laser beam 63 on the mirror 65 to form an image on the surface of the photoconductor 21 for exposure. Rotate the photoreceptor 21,
By scanning the laser beam 63 as described above to form an image, an electrostatic latent image is formed on the surface of the photoconductor 21.

The corona charger 66 is provided upstream of the image forming point of the laser beam 63 in the rotation direction of the photosensitive member 21.
The surface of the photoconductor 21 is uniformly charged. The developing device 67
The photosensitive member 21 is provided downstream of the image forming point in the rotation direction.
, And the electrostatic latent image is developed as a toner image. The transfer paper accommodated in the transfer paper cassette 68 is taken out one by one by a paper feed roller 69, and is synchronized with the exposure of the photoreceptor 21 by a registration roller 70 so that the developing device 6
7, a transfer charger 71 provided further downstream in the rotation direction.
And the toner image is transferred to the transfer paper. A separation charger 72 is provided in the vicinity of the transfer charger 71 and further downstream in the rotation direction. The separation charger 72 removes electricity from the transfer paper on which the toner image has been transferred and separates the transfer paper from the photoconductor 21.

The separated transfer paper is conveyed to a fixing device 74 by a conveyance belt 73, and the toner image is fixed on the transfer paper. The transfer paper on which the image has been formed in this manner is fixed on the discharge tray 75. A cleaner 76 for cleaning the toner remaining on the surface of the photoconductor 21 is provided further downstream of the separation charger 72 in the rotation direction and upstream of the corona charger 66 in the rotation direction, together with a static elimination lamp (not shown). The image formation is repeated by rotating the photoconductor 21.

The configuration of the laser printer 60 is not limited to that shown in FIG. 3, but may be different as long as the photosensitive member according to the present invention can be used. For example, when the outer diameter of the photoconductor 21 is 40 mm or less, the separation charger 72 may not be provided.

The photosensitive member 21 is connected to a corona charger 66,
At least one of the developing device 67 and the cleaner 76 may be physically configured to be a process cartridge. For example, a process cartridge incorporating all of the photoconductor 21, the corona charger 66, the developing device 67, and the cleaner 76, the photoconductor 21, the corona charger 6
A process cartridge incorporating the photoconductor 21 and the developing device 67, a process cartridge incorporating the photoconductor 21 and the cleaner 76, and a process cartridge incorporating the photoconductor 21 and the developing device 67 can be configured. Use of the process cartridge facilitates replacement in a printer or the like.

As the charger 66, in addition to the above-mentioned corona charger, a corotron charger, a scorotron charger,
A sawtooth charger and a roller charger may be used. As the developing device 67, at least one of a contact type and a non-contact type may be used. As the cleaner 76, a blade cleaner, a brush cleaner, or the like may be used.

The static elimination lamp (not shown) may not be provided by devising the timing of applying a high voltage such as a developing bias. In particular, in the case of a small-diameter drum, a low-speed low-end printer, or the like, many of them cannot be provided.

[0068]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The wiping device according to the present invention will be described below with reference to a specific embodiment using the drawings. The wiping device according to the present invention is not limited to the contents described below. FIG. 4 is a schematic explanatory view showing a first embodiment of the apparatus for wiping an organic electrophotographic photosensitive member according to the present invention.

The processing apparatus 101 for wiping and removing the photosensitive layer formed at the lower end of the photosensitive drum 21 includes a solvent tank 103 containing a wiping solvent 102 according to the present invention and a lower end of the photosensitive drum 21. A blade 104 for wiping and removing the formed photosensitive layer; a blade holder 105 for holding the blade 104;
3 and a solvent supply tank 106 for replenishing the solvent.
Here, the blade 104 is a flexible plate-shaped member,
There is no particular limitation as long as it is resistant to the wiping solvent used.

Hereinafter, the wiping process will be described.
After the lower end of the photosensitive drum 21 is immersed in the wiping solvent 102, the blade 104 is brought into contact with the photosensitive layer portion to be removed at the lower end of the photosensitive drum 21, and the photosensitive member 21 is The drum 21 is chucked (sandwiched). Then, by rotating the photosensitive drum 21 or the blade holder 105, the blade 104 scrapes off the excess photosensitive layer (coating) in the chucked portion.

FIG. 5 is a schematic explanatory view showing a second embodiment of the apparatus for wiping an organic electrophotographic photosensitive member according to the present invention. The processing device 201 for wiping and removing the photosensitive layer formed at the lower end of the photoconductor drum 21 includes a cloth-like member 202 for wiping and removing the lower end including the wiping solvent 102 according to the present invention, A holder 203 for holding the shaped member 202, a solvent supply pump 204 for supplying a solvent to the cloth member 202, and a solvent auxiliary tank 205 for replenishing the solvent are provided. Here, the cloth member 202 is a flexible member and is not particularly limited as long as it is resistant to the wiping solvent to be used. However, a thick member having a high absorbency is preferable.

The wiping processing step using the above-described double processing apparatus will be described. The photoreceptor drum 21 is applied to the cloth-like member 202, which is sufficiently impregnated with the wiping solvent 102 supplied by the pump 204 from the solvent auxiliary tank 205 in a predetermined amount.
By pressing or rotating the drum or the cloth-like member, the excess photosensitive layer (coating) on the lower end portion is scraped off. Furthermore, the bottom is uneven (thick)
Dissolve and absorb the coating.

Next, the photosensitive drum, the coating solution, and the wiping solvent used in the embodiments of the present invention will be described in detail with reference to the embodiments.

(Examples 1 to 8, Comparative Examples 1 to 8) 97 parts by weight of methyl isobutyl ketone, 1.5 parts by weight of a bisazo pigment (chlorodiane blue) and butyral resin (Eslec BL-1: manufactured by Sekisui Chemical Co., Ltd.) The mixture containing 0.5 parts by weight was dispersed with a paint shaker for 8 hours to prepare a coating solution for a charge generation layer. Then, using a dip coating apparatus shown in FIG. 1, an aluminum cylindrical conductive substrate having a diameter of 65 mm × 348 mm was immersed in the coating liquid for a charge generation layer, dried, and dried.
μm to form a charge generating layer, and then, on the charge generating layer, 8 parts by weight of tetrahydrofuran, 1 part by weight of a hydrazone compound (4-diethylaminobenzaldehyde-N, N-diphenylhydrazone) and polycarbonate Resin (Z-400: manufactured by Mitsubishi Gas Chemical Company) 1
1 part by weight and a silicone-based leveling agent (SH-200: manufactured by Toray Silicone Co., Ltd.) were mixed and stirred and dissolved. The charge transporting layer coating liquid was again adjusted by using the dip coating apparatus shown in FIG. After drying, a charge transporting layer was formed to have a thickness of 20 μm to prepare a photosensitive drum.

In this process, after the formation of each photosensitive layer, the unnecessary coating film of the photosensitive layer was wiped off using the wiping solvent shown in Table 1 using a wiping apparatus shown in FIG. In particular, in the example where the wiping property was “△”, there was a residual wiping inside the lower end portion of the base, so that the fitting could not be performed with high accuracy when fitting the flange. In addition, those treated with N-methyl-pyrrolidone dissolved to a coating film that did not need to be removed by wiping, and remained on the edges without drying even after drying.

[0076]

[Table 1]

(Examples 9 to 16, Comparative Examples 9 to 16) 6 parts by weight of a copolymerized nylon resin (CM4000: manufactured by Toray Industries, Inc.) was dissolved in 94 parts by weight of methanol to prepare a coating liquid for an undercoat layer. . Next, 2 parts by weight of X-type metal-free phthalocyanine (Fastogen Blue 8120BS: manufactured by Dainippon Ink and Chemicals, Inc.) and vinyl chloride-vinyl acetate-maleic anhydride resin (VMCH: manufactured by Union Carbide) were used as a coating solution for the charge generation layer. 0.7 parts by weight, 0.3 part by weight of a phenoxy resin (PKHH: manufactured by Union Carbide),
One hundred parts by weight of tetrahydrofuran was prepared and dispersed in a ball mill for 8 hours.

Next, 1 part by weight of a butadiene-based charge transporting agent (1,1-bis (p-diethylaminophenyl) -4,4-1,3-butadiene: manufactured by Takasago International Corporation) was used as a coating solution for the charge transporting layer. 0.1 parts by weight of a polyarylate resin (U-100: manufactured by Unitika), 0.8 parts by weight of a polycarbonate resin (Panlite L-1225: manufactured by Teijin Chemicals), 0: Polyester resin (V-200: manufactured by Toyobo) 0 0.1 part by weight of a silicone-based leveling agent (KF-96: manufactured by Shin-Etsu Chemical Co., Ltd.) in an amount of 0.0001 part by weight dissolved in 10 parts by weight of dichloromethane was prepared.

Each of the above coating liquids was applied in exactly the same manner as in Example 1 so as to have a film thickness of 1.5, 0.4 and 17 μm, and finally dried at 80 ° C. for 1 hour to obtain an LBP. An electrophotographic photosensitive member was manufactured.

In this process, after forming each photosensitive layer, an unnecessary thick coating on the lower end portion of the substrate was absorbed and removed with a wiping solvent shown in Table 2 using a wiping apparatus shown in FIG. In particular, in the case where the wiping property was “性”, bubbles could not be sufficiently removed by removal, so that bubbles were generated in the coating film at the lower end after heating and drying. Further, those treated with dichloromethane and N-methyl-pyrrolidone dissolved to a coating film that did not need to be removed by wiping, and remained on the edges without drying even after drying.

[0081]

[Table 2]

[0082]

As described above, according to the present invention, the non-uniform and unnecessary coating on the end of the conductive substrate formed by the dip coating method can be safely removed without adversely affecting the global environment and workers. The wiping process can be performed efficiently. Accordingly, when a drum driving flange or the like is fitted, it is possible to easily insert the flange and to satisfy the runout accuracy of the entire drum. In addition, since there is no bubble generated during heating and drying due to an excess coating film at the lower end portion which is thicker than a predetermined film thickness, the cleaning blade accurately contacts the photoconductor surface, so that cleaning failure and toner It is unlikely to cause dropping, filming, and film failure. Further, since the positioning between the developing tank and the drum is performed with high precision, the image is not blurred, and the toner does not adhere to the drum and drops.

Further, by forming a mixed system with water or a non-halogen organic solvent, the non-uniform and unnecessary coating film at the end of the conductive substrate formed by the dip coating method can be used for the global environment and workers. Thus, it is possible to safely and efficiently perform the wiping process without any adverse effect on the like. In particular, by mixing water with glycol ethers, the flash point of the wiping solvent can be further increased, and the risk of explosion and the like can be reduced. Particularly, by using a mixed system with a non-halogen-based organic solvent, a safe production method without adverse effects on the global environment and workers can be provided. Furthermore, it is possible to control the solubility to the photosensitive layer and the evaporation rate of the wiping solvent, so that if it is necessary to dissolve parts that do not need to be removed, It is possible to perform high-quality wiping without corroding even the resin parts used in the method, reducing consumption and increasing costs.

Further, by using a mixed system of two or more ethers, the flash point of the wiping solvent can be controlled and the danger of explosion and the like can be reduced.
In addition, it is possible to control the solubility to the photosensitive layer, etc., so if it dissolves to the part that does not need to be removed, or if it leaks out of the wiping device, the resin parts used in the device itself Troubles such as corrosion of even kinds do not occur. Furthermore, since the evaporation rate of the wiping solvent can be controlled, the amount of consumption due to spontaneous evaporation other than the processing can be suppressed, the cost can be reduced, and high-quality wiping can be performed without the processing solvent remaining at the edge of the base. Becomes possible.

According to the present invention, since the wiping solvent is a mixed system of at least (A) glycol ethers and (C) cyclic ethers, the unevenness of the conductive substrate formed by the dip coating method is uneven. In addition, it is possible to safely and efficiently remove unnecessary coating films without adversely affecting the global environment and workers. Further, the flash point, solubility, evaporation rate, and the like of the wiping solvent can be easily controlled.

Further, the proteic treatment solvent (A) is 3-methyl-3-methoxy-1-butanol or 3-methyl-3-methoxybutyl acetate, and the treatment solvent (C) is tetrahydrofuran or dioxolane. Because it is a combination, it is possible to safely and efficiently wipe off the non-uniform and unnecessary coating on the end of the conductive substrate formed by the dip coating method without adversely affecting the global environment and workers. This can be performed very easily and accurately. Moreover,
Control of the flash point, solubility, evaporation rate, etc. of the wiping solvent can be performed very easily and optimally.

Further, according to the present invention, the treatment solvent (A)
And the mixing ratio (A) :( C) of the processing solvent (C) is 1: 5-
When the ratio is 2: 1 (volume ratio), the flash point, solubility, evaporation rate, and the like of the wiping solvent can be controlled to optimal conditions in the process, thereby providing a method of manufacturing a high-quality photoconductor. We were able to.

Further, the organic solvent for wiping treatment according to the present invention includes polycarbonate and its copolymer, polyester, polyamide, copolymerized nylon, polyarylate,
Polystyrene, polyvinyl alcohol, polyvinyl butyral, vinyl chloride-vinyl acetate resin, phenoxy resin, polyimide resin, epoxy resin and other commonly used resin groups for organic electrophotographic photoreceptors can be easily dissolved and efficiently and high quality Can be manufactured.

Further, according to the present invention, in a solvent tank filled with the processing solvent, the blade or sponge-like wiping member is slid in contact with the wiping processing solvent, so that an unnecessary coating film on the end of the photosensitive member substrate is formed. In particular, the inside and the lower end of the base can be efficiently and accurately wiped and removed.

Further, by pressing the cloth-like wiping member containing the processing solvent against the lower end surface of the base, it is possible to efficiently and accurately remove unnecessary coating films particularly on the lower end surface of the base. It is. Further, since the non-uniform (thick) film thickness portion at the lower end can be made thinner by sucking it toward the member, the generation of bubbles after heating and drying can be prevented without completely wiping and removing the lower end.

Further, according to the present invention, the non-uniform and unnecessary coating film on the end of the conductive substrate formed by the dip coating method can be used without causing any adverse effects on the global environment and workers, and can also be used to prevent the occurrence of a flash explosion or the like. It is possible to wipe off and remove efficiently and accurately without danger, safely and without unnecessarily increasing the cost. This makes it possible to provide an apparatus for manufacturing a high-quality organic electrophotographic photoreceptor.

Further, according to the present invention, the non-uniform and unnecessary coating film on the end of the conductive substrate formed by the dip coating method can be used without causing adverse effects (carcinogenicity) on the global environment and workers, and can be ignited. The risk of explosion and the like can be reduced, and the wiping and removal can be performed efficiently and with high accuracy without incurring unnecessarily high cost. This makes it possible to provide a high-quality organic electrophotographic photoreceptor that is free from image defects and toner scattering, and that has little vibration of the drum itself when a flange or the like is fitted.

Finally, it is possible to provide an image forming apparatus that outputs a high-quality image free of image defects and toner scattering.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing an example of a coating apparatus for dip-coating a photosensitive layer on a cylindrical conductive substrate.

FIG. 2 is a cross-sectional view of a main part showing a lower end portion of a photosensitive drum after dip coating.

FIG. 3 is a schematic explanatory view showing an example of an image forming apparatus according to the present invention.

FIG. 4 is a schematic explanatory view showing a first embodiment of an apparatus for wiping an organic electrophotographic photosensitive member according to the present invention.

FIG. 5 is a schematic explanatory view showing a second embodiment of the apparatus for wiping an organic electrophotographic photosensitive member according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical conductive base 4 Coating tank 5 Coating liquid 20 Coating (photosensitive layer) 20a, 20b, 20c Extra coating (photosensitive layer) 21 Photoconductor drum 60 Image forming apparatus (laser printer) 101, 201 Such a wiping apparatus 102 wiping processing solvent 104 blade-like wiping member 202 cloth-like wiping member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masayuki Sakamoto 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Makoto Kurokawa 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Co., Ltd. EA43

Claims (13)

[Claims] 1. A method for producing an organic electrophotographic photoreceptor, wherein the processing solvent for removing an unnecessary photosensitive layer on the photoreceptor substrate contains at least a glycol ether. 2. The process according to claim 1, wherein the processing solvent is a mixture of at least (A) glycol ethers, (B) water or a non-halogen organic solvent. Method. 3. A process solvent for removing an unnecessary photosensitive layer on a photoconductor substrate, wherein the process solvent is a mixed system of at least two or more ethers. Production method. 4. A method for producing an organic electrophotographic photoreceptor, wherein the processing solvent is a mixture of at least (A) a glycol ether and (C) a cyclic ether. 5. The method according to claim 1, wherein the treatment solvent (A) is 3-methyl-3-methoxy-1-butanol or 3-methyl-3-methoxybutyl acetate. A method for producing an organic electrophotographic photoreceptor according to any one of the preceding claims. 6. The method according to claim 4, wherein the processing solvent (C) is tetrahydrofuran or dioxolan. 7. The mixing ratio of the processing solvent is (A) :( C) =
The method for producing an organic electrophotographic photoreceptor according to any one of claims 4 to 6, wherein the ratio is 1: 5 to 2: 1 (volume ratio). 8. The resin used for the photosensitive layer treated with a treatment solvent is polycarbonate and its copolymer, polyester, polyamide, copolymerized nylon, polyarylate, polystyrene, polyvinyl alcohol, polyvinyl butyral, vinyl chloride-vinyl acetate. The method according to any one of claims 1 to 7, wherein the photosensitive material is at least one selected from the group consisting of a system resin, a phenoxy resin, a polyimide resin, and an epoxy resin. 9. The method according to claim 1, wherein a blade or a sponge-like wiping member is provided in a solvent tank filled with the processing solvent, and the photosensitive layer is removed by sliding contact. 2. The method for producing an organic electrophotographic photosensitive member according to claim 1. 10. The photosensitive layer according to claim 1, wherein the photosensitive layer is removed by pressing a lower end surface of the cylindrical photosensitive body against a cloth-like wiping member containing a processing solvent. A method for producing an organic electrophotographic photoreceptor according to any one of the preceding claims. 11. The method according to claim 1, wherein
An apparatus for producing an organic electrophotographic photoreceptor, comprising using the processing solvent described in the above section. 12. The method according to claim 1, wherein:
An organic electrophotographic photoreceptor produced using the processing solvent described in the above item. 13. The method according to claim 1, wherein:
13. An image forming apparatus, comprising: an organic electrophotographic photosensitive member manufactured by using the processing solvent according to any one of the above items.