JP4697769B2 - Method for producing electrophotographic photosensitive member - Google Patents

Description

The present invention relates to the production how the electrophotographic photosensitive member.

  When an electrophotographic photosensitive member is manufactured, it is common to immerse the base of the electrophotographic photosensitive member in a coating solution to form a coating film. In this case, since the substrate of the electrophotographic photosensitive member is immersed in the coating solution up to the end, a coating film is formed on the entire surface of the substrate. When an electrophotographic photosensitive member having a coating film formed on the entire surface of the substrate in this way is incorporated into an electrophotographic apparatus, the coating film is peeled off by an abutting roll at the end that determines the gap between the developing roll and the electrophotographic photosensitive member, and an accurate image is obtained. Since the gap cannot be set and image defects are caused by the powder of the peeled coating film, the coating film on both ends of the electrophotographic photoreceptor is removed.

  As a method for removing the coating film on both ends, for example, a method of sequentially unwinding a wiping tape made of a nonwoven fabric, impregnating the wiping tape with a solvent, and then removing it by contact with an electrophotographic photosensitive member; A method of unwinding a wiping tape made of, and impregnating the wiping tape with a solvent and then removing it by contact with an electrophotographic photosensitive member, a method of using a wiping tape made of a nonwoven fabric with a concavo-convex structure on one side, and the like are known. (For example, refer patent documents 1-3.).

  However, when wiping with the above removal method, burrs are generated on the wiping end surface, the burrs are peeled off by rubbing with a cleaning blade, black spots caused by the peeled powder are generated in the image, or peeling The film peeled off from the end face of the part, the edge of the cleaning blade was damaged by burrs, and an image defect due to the scratch was generated, which was not yet satisfactory.

  In addition, ether-based, alcohol-based, chlorine-based and ketone-based solvents have been used as solvents to be impregnated in the wiping tape. Specifically, it has been proposed to use tetrahydrofuran, methanol, chloroform, methylene chloride, methyl ethyl ketone, acetone, dioxolane or the like alone or in combination (see, for example, Patent Document 4).

However, when a low-boiling solvent such as tetrahydrofuran or dioxolane is used, the tape peelability is good, but the peeled coating film end faces are often not jagged. This seems to be due to the high evaporation rate and the difference in solvent content on the tape surface. Moreover, a chlorinated solvent is not preferable environmentally. In addition, ether-based, alcohol-based, and ketone-based solvents have a risk of ignition and have been desired to be improved.
JP-A-4-65376 JP-A-6-138670 JP-A-9-281725 JP 2003-98696 A

It is an object of the present invention to provide an electrophotographic photosensitive member that peels off when the edge of a coating film formed by drying a film including a photosensitive layer on a conductive substrate is peeled off so that the peeled film edge surface does not become jagged. it is to provide a manufacturing how.

  The present invention is achieved by adopting the following configuration.

1. A step of forming a film by applying a coating solution containing a photosensitive layer on a conductive substrate, a step of forming a coating film by drying the film formed by coating at 100 to 145 ° C., a coating film formed by drying In the method for producing an electrophotographic photosensitive member, which has a step of removing the coating film by peeling the coating film by contacting the end of the substrate with a wiping tape impregnated with a stripping solution.
The stripping solution has a boiling point of 200 ° C. or lower and a cyclic ether as a main solvent, and water is 0.5 to 9 . A method for producing an electrophotographic photoreceptor, comprising 0% by mass.

2. 2. The method for producing an electrophotographic photosensitive member according to 1 above , wherein the cyclic ether is tetrahydrofuran .

3. 2. The method for producing an electrophotographic photosensitive member according to 1 above , wherein the cyclic ether is dioxolane .

The method for producing an electrophotographic photoreceptor (hereinafter also simply referred to as a photoreceptor) of the present invention comprises the steps of coating film formed by drying a film containing a photosensitive layer on a conductive substrate (hereinafter also simply referred to as a substrate). Can be peeled off satisfactorily and the peeled end face of the coating film can be peeled off so as not to be jagged, so that a good print image free from image defects can be obtained when an image is formed.

  Furthermore, the stripping solution used in the present invention is environmentally friendly because it does not use a halogenated solvent, and since it contains water, it has an excellent risk of ignition.

  The present inventors contacted the end surface of a photoreceptor having a coating film containing a photosensitive layer on a substrate with a wiping tape impregnated with a stripping solution, and when the end coating film was peeled off, We studied to prevent jaggedness. The phenomenon that the edge of the peeled film becomes jagged is confirmed to occur when a solvent that dissolves the film well and has a high evaporation rate is used, and is estimated to be due to the difference in the stripping solution content on the tape surface. .

  The present inventors have found that when a stripping solution in which a certain amount of water is added to a specific solvent is used, the peeled coating film end face does not become jagged, and the peeled outer surface is aligned. This is presumed that the water plays the role of a high-boiling solvent, increases the uniformity of the solvent in the tape, and eliminates the difference in the solvent content on the tape surface, thereby providing a jagged coating film end surface. Furthermore, it has been found that even when a certain amount of water is added to a specific solvent, the stripping performance of the stripping solution does not deteriorate and is good.

  It was also found that the risk of ignition was reduced because water was added to the stripping solution.

  Hereinafter, the present invention will be described in detail.

[Stripping solution]
The stripping solution used by impregnating the wiping tape used in the present invention has a boiling point of 200 ° C. or less, preferably 50 to 160 ° C., and a cyclic ether as a main solvent, and contains 0.5 to 9 water. . 0 mass%, Preferably it contains 1.0-8.0 mass%.

  The boiling point of the main solvent is 200 ° C. or less, preferably 50 to 160 ° C. When a main solvent having a boiling point in this range is used, the releasability and the solvent penetration into the wiping tape are good, the remaining of the coating film does not occur, the drying of the coating film removal section does not slow down, and the production speed is also high. It can be secured.

The main solvent is selected from cyclic ethers .

The main solvent used in the present invention, Te tetrahydrofuran (THF), and cyclic ethers such as dioxolane.

The stripping solution should contain 0.5 to 9 water. Containing 0% by mass, preferably 1.0 to 8.0% by mass. When the stripping solution contains water in this range, the uniformity of the stripping solution in the wiping tape is increased, and it is estimated that the difference in stripping solution content on the stripping tape surface is eliminated, and the peeled coating film end surface does not become jagged. Furthermore, the risk of ignition due to electrostatic friction, ignition, etc. can be reduced by containing water. In addition, even if stripping solution contains the water of this range, the removal performance of a coating film is securable.

The stripping solution may be used as a mixed solvent (water is not counted) by mixing another organic solvent with the main solvent. In this case, the main solvent is preferably contained in an amount of 60% by mass or more. Other organic solvents to be mixed with the main solvent can be mixed with the main solvent without phase separation, and water is 0.1 to 9 . There is no limitation as long as it does not cause phase separation even when 0 mass% is mixed, but a non-halogen solvent is preferable.

[Removal of coating film]
The peeling device used in the present invention is a device that peels a coating film by bringing a wiping tape impregnated with a stripping solution into contact with the coating film of the photoreceptor.

  In the present invention, the peeling width for peeling the coating film at the end of the photoreceptor is preferably 10 to 30 mm.

  The material of the wiping tape is not particularly limited as long as it can be impregnated with the stripping solution to be used, is not affected by the stripping solution to be used, and can withstand the tension during wiping.

  Specifically, polyamide fibers such as 6 nylon fibers and 66 nylon fibers, polyester fibers such as polyethylene terephthalate fibers and polybutylene terephthalate fibers, acrylic fibers, vinylon fibers, vinylidene fibers, polyurethane fibers, fluorine fibers, aromatics Synthetic fibers such as polyamide fibers such as polyamide fibers, polyethylene fibers and polypropylene fibers, regenerated fibers such as rayon fibers, semi-synthetic fibers such as acetate fibers, inorganic fibers such as carbon fibers, plant fibers such as cotton fibers and hemp fibers, Animal fibers such as wool can be used.

FIG. 1 is a schematic view showing an example of a peeling apparatus using a wiping tape.
Show.

  In FIG. 1, 1 is a wiping tape, 3 is a photoconductor, 40 is a stripping solution tank, 50 is an impregnation portion of the stripping solution into the wiping tape, 8 is an original winding roll, and 9 is a winding roll.

  FIG. 2 is a cross-sectional view of the coating film end face of the photoreceptor. FIG. 2A shows a state in which the maximum film thickness (X μm) of the coating film end face is larger than the film thickness (Y μm) of the central coating film. FIG. 2B shows a state where the maximum film thickness (X μm) of the coating film end face is smaller than the film thickness (Y μm) of the central coating film.

  In FIG. 2, 5 is a substrate, 4 is a coating film, X is the maximum film thickness of the coating film end face (within ± 5 mm from the boundary between the wiped portion and the unwiped portion), and Y is the central coating film (center) 10 points average film thickness of part ± 2 cm), Z indicates the height (Z = X−Y, including negative number) of burrs (small convex parts).

  In addition, the measurement of a burr | flash can be performed using a contact-type film thickness measuring device.

  In the film thickness profile of the coating film, the burr height (Z = XY, including negative numbers) is preferably less than 40 μm, more preferably less than 30 μm, and even more preferably less than 20 μm.

  If the height of the burr is less than 40 μm, it is possible to suppress the occurrence of image black spots caused by the powder peeled from the burr, film peeling from the end face, and scratches on the edge of the cleaning blade.

  Next, a method for wiping the coating film will be described. The wiping method is a method of wiping the coating film by bringing the wiping tape into contact with the coating film of the rotating photosensitive member in the state where the wiping tape is impregnated with an impregnation solution that dissolves or swells the coating film.

  The moving direction of the wiping tape is not particularly limited, but it is preferable that the wiping tape can be wiped in a short time by setting it in the direction opposite to the rotation direction of the photoreceptor.

  FIG. 3 is a schematic view showing an example of a method for bringing the wiping tape into contact with the photosensitive member.

  In the figure, 1 is a wiping tape, 2 is a pressure contact roll, 3 is a photoreceptor, 40 is a stripping solution tank, 50 is an impregnation part of the stripping solution to the wiping tape, 8 is an original winding roll, and 9 is a winding roll.

  As a specific method of bringing the wiping tape into contact with the end portion of the coating film of the photoreceptor, FIGS. 3A, 3B, and 3C can be exemplified.

  In FIG. 3A, the wiping tape 1 is applied with a certain tension between the original winding roll 8 and the winding roll 9, and is brought into contact with the photoreceptor 3 by the pressure contact roll 2.

  FIG. 3B shows a method in which the wiping tape 1 is brought into contact with the photosensitive member 3 by using two pressure contact rolls 2 in FIG.

  FIG. 3C shows a method in which the take-up roll 9 in FIG. 3A is changed to the nip drive roll 6 and the wiped tape 1 that has been wiped off is collected in the collection container 7. Since the wiping tape 1 that has been wiped off is impregnated with a solvent, it is preferable to collect the wiping tape 1 in the collection container 7 because there is little risk of vaporizing the solvent in the room.

[Photoconductor]
The photoreceptor obtained by the present invention is obtained by peeling off the end coating film of the coating film including the photosensitive layer formed on the substrate.

  Hereinafter, the substrate, the conductive layer, the intermediate layer, and the charge generation layer, the charge transport layer, and the protective layer, which are the photosensitive layer, constituting the photoreceptor according to the present invention will be described.

(Substrate)
Either a sheet or a cylindrical substrate may be used as the substrate used in the photoreceptor, but a cylindrical substrate is preferable for designing an image forming apparatus in a compact manner.

  The cylindrical substrate means a cylindrical substrate necessary to be able to form an image endlessly by rotating, and a conductive substrate having a straightness within a range of 0.1 mm or less and a deflection of 0.1 mm or less is preferable. By setting the straightness and shake range within the above ranges, good image formation can be achieved.

  As the base material, a metal drum such as aluminum or nickel, a plastic drum on which aluminum, tin oxide, indium oxide or the like is deposited, or a paper / plastic drum coated with a conductive substance can be used. The substrate preferably has a specific resistance of 103 Ωcm or less at room temperature.

  In addition, the substrate having a surface formed with an alumite film that has been sealed may be used. The alumite treatment is usually performed in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, sulfamic acid, etc., but anodizing treatment in sulfuric acid gives the most preferable result. In the case of anodizing treatment in sulfuric acid, the sulfuric acid concentration is preferably 100 to 200 g / L, the aluminum ion concentration is 1 to 10 g / L, the liquid temperature is about 20 ° C., and the applied voltage is preferably about 20 V. It is not limited. The average film thickness of the anodized film is usually 20 μm or less, particularly preferably 10 μm or less.

(Conductive layer)
In the photoreceptor according to the present invention, a conductive layer may be provided on the substrate. The conductive layer is a layer basically composed of a binder resin and a conductive pigment. The thickness of the conductive layer is preferably from 0.3 to 20 μm, more preferably from 1 to 15 μm.

  The binder resin used in the conductive layer is a thermosetting resin so as not to dissolve in the solvent used in the intermediate layer in order to maintain a uniform coating film even after the intermediate layer is applied.

(Middle layer)
In the present invention, an intermediate layer (including an undercoat layer) is provided between the substrate and the photosensitive layer in order to improve adhesion between the substrate and the photosensitive layer or to prevent charge injection from the substrate. Examples of the material for the intermediate layer include polyamide resins, vinyl chloride resins, vinyl acetate resins, and copolymer resins containing two or more of these resin repeating units. Of these resins, a polyamide resin is preferable as a resin capable of reducing an increase in residual potential due to repeated use. The film thickness of the intermediate layer using these resins is preferably 0.01 to 1.0 μm.

  Examples of the intermediate layer preferably used in the present invention include an intermediate layer using a curable metal resin obtained by thermosetting an organic metal compound such as a silane coupling agent or a titanium coupling agent. The thickness of the intermediate layer using a curable metal resin is preferably 0.1 to 2 μm.

  An intermediate layer preferably used in the present invention includes an intermediate layer in which inorganic particles are dispersed in a binder resin. The average particle diameter of the inorganic particles is preferably 0.01 to 1 μm. In particular, an intermediate layer in which N-type semiconductive fine particles subjected to surface treatment are dispersed in a binder is preferable. For example, an intermediate layer in which titanium oxide having an average particle size of 0.01 to 1 μm, which has been surface-treated with silica / alumina treatment and a silane compound, is dispersed in a polyamide resin. The film thickness of such an intermediate layer is preferably 1 to 20 μm.

(Charge generation layer)
The charge generation layer contains a charge generation material (CGM). Other substances may contain a binder resin and additives as necessary.

  A known charge generation material (CGM) can be used as the charge generation material (CGM). For example, a phthalocyanine pigment, an azo pigment, a perylene pigment, an azulenium pigment, or the like can be used. Among these, CGM which can minimize the increase in residual potential due to repeated use has a crystal structure capable of taking a stable aggregate structure among a plurality of molecules, specifically, a phthalocyanine pigment having a specific crystal structure, CGM of a perylene pigment is mentioned. For example, CGMs such as titanyl phthalocyanine having a maximum peak at a Bragg angle 2θ of 27.2 ° with respect to Cu—Kα rays and benzimidazole perylene having a maximum peak at 2θ of 12.4 have little deterioration due to repeated use. Potential increase can be reduced.

  When a binder resin is used as a dispersion medium for dispersing the charge generation material in the charge generation layer, a known resin can be used as the binder resin, but as a preferable resin, a formal resin, a butyral resin, a silicon resin, or a silicon-modified butyral is used. Examples thereof include resins and phenoxy resins. The ratio of the binder resin to the charge generating material is preferably 20 to 600 parts by mass with respect to 100 parts by mass of the binder resin. By using these resins, the increase in residual potential associated with repeated use can be minimized. The thickness of the charge generation layer is preferably 0.01 μm to 2 μm.

(Charge transport layer)
The charge transport layer contains a charge transport material (CTM) and a binder resin. Other substances may contain additives such as antioxidants as necessary.

  As the charge transport material (CTM), the oligomer CTM is used. In addition to the oligomer CTM, for example, a triphenylamine derivative, a hydrazone compound, a styryl compound, a benzidine compound, a butadiene compound, or the like can be used in combination. These charge transport materials are usually dissolved in a binder resin to form a layer. The thickness of the charge transport layer is preferably 10 to 40 μm.

  Examples of the binder resin used in the charge transport layer (CTL) include polystyrene-acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, Mention may be made of polycarbonate resins, silicone resins, melamine resins and copolymer resins containing two or more of the repeating unit structures of these resins. In addition to these insulating resins, high molecular organic semiconductors such as poly-N-vinylcarbazole can be used.

  A polycarbonate resin is particularly preferable as the binder resin. The polycarbonate resin is particularly preferable in improving the dispersibility and electrophotographic characteristics of CTM. The ratio of the binder resin to the charge transport material is preferably 10 to 200 parts by mass with respect to 100 parts by mass of the binder resin.

  The charge transport layer preferably contains an antioxidant. Typical examples of the antioxidants prevent or suppress the action of oxygen on auto-oxidizing substances existing in the photoreceptor or on the photoreceptor surface under light, heat, discharge, or the like. It is a substance with properties. As the antioxidant, a known one can be used, and examples thereof include 2,6-di-tert-butyl-4-methylphenol.

(Protective layer)
In the photoreceptor according to the present invention, a durability improving layer or a charge injection layer functioning as a charge injection may be provided as a protective layer on the charge transport layer for the purpose of improving the film durability.

  The durability improving layer is basically composed of a curable binder resin, and may be a layer formed by adding a charge transport material as necessary. The film thickness of the durability improving layer is preferably 0.3 to 10 μm, and more preferably 1 to 5 μm.

  The charge injection layer is a layer basically composed of conductive fine particles and a curable binder resin.

As the conductive fine particles of the charge injection layer, fatty acid salts, higher alcohols, sulfate esters, fatty acid amines, quaternary ammonium salts, alkyl pyridium salts, polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, Anionic, cationic, or nonionic organic electrolytes such as sorbitan alkyl esters and imidazoline derivatives; metals such as Au, Ag, Cu, Ni, Al; ZnO, TiO ₂ , SnO ₂ , In ₂ O ₃ , Sb ₂ O Metal oxides such as _3- containing SnO ₂ and In ₂ O ₃ -containing SnO ₂ ; metal fluorides such as MgF ₂ , CaF ₂ , BiF ₂ , AlF ₂ , SnF ₂ , SnF ₄ , TiF ₄ ; tetrainpropyl titanate, tetra Normal butyl titanate, titanium acetylacetonate, titanium lactate ethyl ester And mixtures thereof, and the like; organic titanium compounds. The thickness of the charge injection layer is preferably 0.3 to 10 μm, and more preferably 1 to 5 μm.

  The volume resistance of the charge injection layer is preferably set in the range of 1010 to 1015 Ω · cm, and more preferably 1010 to 1014 Ω · cm. Since the film strength becomes weaker as the amount of conductive particles increases, it is preferable to reduce the amount of conductive particles within a range where the resistance and residual potential of the charge injection layer are acceptable.

  The preferred layer structure of the photoconductor used in the present invention is exemplified above, but the other layer structure of the photoconductor may be used.

  Solvents or dispersion media used for forming conductive layers, intermediate layers, charge generation layers, charge transport layers, protective layers and the like include acetone, methyl ethyl ketone (MEK), methyl isopropyl ketone, cyclohexanone, toluene, xylene, tetrahydrofuran (THF). ), Dioxolane, dioxane, methyl alcohol, ethyl alcohol, butyl alcohol, isopropyl alcohol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl cellosolve and the like. Although this invention is not limited to these, Butyl alcohol, methyl ethyl ketone, tetrahydrofuran, etc. are used preferably. These solvents may be used alone or as a mixed solvent of two or more.

  Further, the coating solution for each layer is preferably filtered with a metal filter, a membrane filter or the like in order to remove foreign matters and aggregates in the coating solution before entering the coating step. For example, it is preferable to select a pleat type (HDC), a depth type (profile), a semi-depth type (profile star), etc., manufactured by Nippon Pole Co., Ltd. according to the characteristics of the coating solution and perform filtration.

  Coating methods such as dip coating, spray coating, circular amount regulation type coating, etc. are used as the coating processing method for manufacturing the photoreceptor, but the upper layer side coating processing does not dissolve the lower layer film as much as possible. Therefore, in order to achieve uniform coating processing, it is preferable to use a coating processing method such as spray coating or circular amount regulation type (a circular slide hopper type is a typical example). The charge injection layer is particularly preferably the above-described circular amount regulation type coating method. The circular amount regulation type coating is described in detail in, for example, Japanese Patent Application Laid-Open No. 58-189061.

  It should be noted that the coating film pool (unnecessary coating film) generated at the bottom of the substrate during dip coating dissolves in the next coating solution, contaminates the coating solution, or contaminates the transport device in the next process. It is preferable to apply the next coating film after removing with a peeling member.

The stripping solution has a boiling point of 200 ° C. or lower and a cyclic ether as a main solvent, and the stripping solution contains 0.5 to 9 water. It is preferable to contain 0% by mass.

  As the peeling member, a brush, sponge, cloth, polymer fiber cloth, or the like can be used. Among these, a brush is preferable.

  The apparatus for removing the coating pool is not particularly limited as long as a stripping solution and a stripping member can be used.

  FIG. 4 is a schematic view showing a coating pool at the lower end of the substrate.

  In the figure, a represents a substrate, PL represents a coating film, and E represents a pool of coating films (unnecessary coating film).

  When the coating solution is applied by a dip coating method, the coating solution flows down to the lower end portion of the substrate to form a coating pool as shown in FIG.

  FIG. 5 is a cross-sectional view showing an example of a removing device for removing the coating pool.

  The substrate a is gripped by the substrate transport means 7 so as to be movable up and down, and is brought into contact with a peeling member 55 provided on a coating film removing table (coating film removing means) 54 of the coating film removing device 5. The coating film removing table 54 is also provided with a sponge-like substrate holding member 541, and the substrate a is supported at its lower end by a substrate holding table and a peeling member. The coating film removing table 54 is designed to be rotatable by a motor drive or the like. After the coating film is formed on the substrate, the photosensitive member is placed on the coating film removing table 54 by the conveying means 7 having a gripping means (O-ring chuck, air picker chuck, etc.) for gripping the inside of the substrate, and the lower end of the photosensitive member Is brought into contact with the peeling member 55 (FIG. 5A). At this time, the coating film removal stand 54 is in a state of coming out of the liquid surface of the stripping solution tank 51 which is a cleaning means. With the residual solvent of the edge coating film on the substrate being 60% by mass or less, the coating film removing table 54 is rotated, and the coating film on the lower end portion of the substrate is wiped off with the peeling member 55 along with the rotation. After this wiping is completed, the substrate is lifted by the substrate conveying means 7 (also serving as a separating means) and separated from the coating film removing table 54. Thereafter, the coating film removing table 54 is immersed in the stripping solution 51E of the stripping solution tank 51 as a cleaning unit by the rotation of a cylinder (moving unit of the coating film removing unit) 542 that allows the coating film removing table 54 to move up and down. (Fig. 5 (b)) In the stripper tank, the coating strip removal table including the stripping member is cleaned by combining the vertical movement and rotation of the coating strip removal table using an ultrasonic cleaner and cylinder. Is done. Thereafter, the cylinder 542 is rotated again to be lifted onto the liquid surface of the stripping solution tank 51 to prepare for the removal of the next coating film. Further, it is preferable to install an ultrasonic transducer U in the stripping solution tank to enhance the cleaning efficiency of the coating film removing means. As shown in FIG. 5, when two or more substrate coating films are removed simultaneously, a partition plate 59 is provided between the coating film removing means, and a defect caused by rebounding during each substrate coating removal. It is preferable to prevent the occurrence.

[Image formation]
The image forming apparatus used in the present invention is not particularly limited as long as the above-prepared photoconductor can be mounted and an image can be formed.

  FIG. 6 is a cross-sectional view showing an example of an electrophotographic image forming apparatus that forms an image using a photoreceptor.

  An electrophotographic image forming apparatus is an apparatus that uses a photoreceptor to form an image by repeating charging, exposure, development, transfer, separation, and cleaning steps.

  Hereinafter, the electrophotographic image forming apparatus of FIG. 6 will be described. Light is emitted from the semiconductor laser light source 121 based on information read by a document reading device (not shown). This is scanned by the polygon mirror 122 and irradiated onto the surface of the photoreceptor through an fθ lens 123 that corrects image distortion, thereby forming an electrostatic latent image by a digital exposure method. The photoconductor 3 is uniformly charged by the charger 115 in advance, and starts rotating clockwise in accordance with the timing of light irradiation.

  The electrostatic latent image on the surface of the photoreceptor is reversely developed by the developing device 116 to form a toner image. The formed toner image is transferred by the action of the transfer unit 117 to the transfer body 118 that has been transported in time. Further, the photosensitive member 3 and the transfer member 118 are separated by a separator (separation pole) 119, and the toner image is transferred and supported on the transfer member 18, guided to the fixing device 10, and fixed to form a print image. .

  Thereafter, the non-transferred toner remaining on the surface of the photoconductor is cleaned by a cleaning blade type cleaning device 111, and the photoconductor 3 is subjected to pre-charge exposure (PCL) 12 to remove the residual charge, and the next image. Again, the charger 115 is uniformly charged.

  The transfer body 118 is typically plain paper, but is not particularly limited as long as it can transfer an unfixed image after development, and includes an OHP PET base and the like.

  The cleaning blade 113 uses a rubber-like elastic body having a thickness of about 1 to 30 mm, and urethane rubber is often used as a material.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, the aspect of this invention is not limited to this.

[Fabrication of end face unpeeled photoreceptor 1]
<Substrate>
As a substrate, an aluminum drum subjected to Compass processing with Rz 1.8 μm was used.

<Intermediate layer>
An intermediate layer coating solution was prepared by dissolving the following composition. The coating solution was applied onto the substrate by a dipping method to form an intermediate layer coating film. Then, using the removing apparatus shown in FIG. 5, the unnecessary coating film was removed with an intermediate layer coating film removing solution (methanol / dioxolane = 2/1 mass ratio). Then, it dried for 30 minutes at 100 degreeC, and formed the intermediate | middle layer whose film thickness is 1.0 micrometer.

Ethylene-vinyl acetate copolymer “ELBACS 4260” (Mitsui DuPont Chemical) 50g
Toluene / n-butyl alcohol = 5/1 (mass ratio) 2000 g
<Charge generation layer>
The following composition was dispersed using a sand mill for 17 hours to prepare a charge generation layer coating solution. The coating solution was applied onto the intermediate layer by a dipping method to form a charge generation layer coating film. Then, the unnecessary coating film was removed with the charge generation layer coating film removal liquid (MEK / dioxolane = 2/1 mass ratio) using the removal apparatus shown in FIG. Next, the film was dried at 100 ° C. for 30 minutes to form a charge generation layer having a thickness of 1.5 μm.

Titanylphthalocyanine “CGM-1” (having strong peaks at 9.5 °, 15.0 °, 24.1 ° and 27.3 ° of the Bragg angle (2θ ± 0.2 °) in the characteristic X-ray diffraction of CuKα Oxytitanium phthalocyanine) 100g
Silicone resin "KR-5240" (manufactured by Shin-Etsu Chemical) 100g
1000 ml of t-butyl acetate
<Charge transport layer>
The following composition was dissolved to prepare a coating solution for a charge transport layer. This coating solution was dip-coated on the charge generation layer to form a charge transport layer coating film. Then, the unnecessary coating film was removed with the charge transport layer coating film pool removing liquid (THF) using the removing apparatus shown in FIG. Thereafter, the film was dried at 110 ° C. for 60 minutes to form a charge transport layer having a film thickness of 23 μm, and “end part non-peeled photoreceptor 1” was produced.

CTM-1 500g
Polycarbonate “Z-200” (Mitsubishi Gas Chemical Co., Ltd.) 560 g
Dioxolane (bp74-75 ° C) 2800ml
Methylphenyl silicone oil “KF-54” (manufactured by Shin-Etsu Chemical Co., Ltd.)
100ppm added to the total solid content

[Fabrication of edge-unpeeled photoreceptor 2]
<Substrate>
As the substrate, an aluminum drum subjected to Compass processing with Rz 1.6 μm was used.

<Intermediate layer>
An intermediate layer coating solution was prepared by dissolving the following composition. This coating solution was applied onto the substrate to form an intermediate coating film. Then, the unnecessary coating film was removed with the intermediate | middle layer coating film removal liquid (methanol / THF = 3/1 mass ratio, moisture content 3.0 mass%) using the removal apparatus shown in FIG. Subsequently, it dried and hardened at 130 degreeC for 30 minutes, and formed the 1.0 micrometer-thick intermediate | middle layer.

Titanium chelate compound "TC-750" (Matsumoto Pharmaceutical Co., Ltd.) 30g
Silane coupling agent "KBM-503" (Shin-Etsu Chemical Co., Ltd.) 17g
150 ml of 2-propyl alcohol
<Charge generation layer>
The following composition was mixed and dispersed for 10 hours using a sand mill to prepare a charge generation layer coating solution. This coating solution was applied onto the intermediate layer by a dip coating method to form a charge generation layer coating film. Then, the unnecessary coating film was removed with the charge generation layer coating film accumulation removal liquid (MEK / THF = 3/1 mass ratio, moisture content 0.7 mass%) using the removal apparatus shown in FIG. Subsequently, it heat-dried at 100 degreeC for 10 minute (s), and the charge generation layer with a film thickness of 0.2 micrometer was formed.

Hydroxygallium phthalocyanine crystal “CGM-2” (CuKα Bragg angle 2θ ± 0.2 ° is 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 °, 25.1 ° 60 g with a strong peak at 28.3 °)
700 g of silicon resin solution “KR5240” (manufactured by Shin-Etsu Chemical)
Methyl ethyl ketone 2000ml
<Charge transport layer>
The following composition was mixed and dissolved to prepare a charge transport layer coating solution. This coating solution was applied onto the charge generation layer by a dip coating method to form a charge transport layer coating film. Then, using the removing apparatus shown in FIG. 5, the unnecessary coating film was removed with a charge transport layer coating film removing solution (THF / dioxolane = 1/1 mass ratio, water content 3.0 mass%). Subsequently, it dried at 120 degreeC for 1 hour, and formed the 20-micrometer-thick charge transport layer.

CTM-2 200g
Bisphenol Z-type polycarbonate “TS2050” (manufactured by Teijin Chemicals Ltd.)
300g
Tetrahydrofuran 2000ml

<Protective layer>
1000 g of methyltrimethoxysilane and 533 g of dimethyldimethoxysilane are dissolved in 2.54 L of butyl alcohol, 400 ml of 3% acetic acid aqueous solution is added thereto, and the mixture is heated and stirred at 60 ° C. for 2 hours. After standing overnight at room temperature, 821 g of methanol silica sol (concentration 30%: manufactured by Nissan Chemical Co., Ltd.) was added thereto, 427 g of dihydroxymethyltriphenylamine was further added, and 28.7 g of aluminum tetraacetylacetonate was added as a curing catalyst and dissolved by stirring. A coating solution for a protective layer having a solid content concentration of 30% was prepared. This coating solution was applied onto the charge transport layer by a circular amount regulating type coating device to form a protective layer coating film having a dry film thickness of 3.5 μm. Then, the unnecessary coating film was removed with the protective layer coating film removal liquid (methanol / THF = 4/1 mass ratio) using the removal apparatus shown in FIG. Subsequently, it dried and hardened at 120 degreeC for 1 hour, the 6-micrometer-thick protective layer (charge injection layer) was formed, and "end part exfoliation photoconductor 2" was produced.

[Fabrication of edge-unpeeled photoreceptor 3]
<Substrate>
An uncut aluminum drum was used as the substrate.

<Conductive layer>
The following composition was dissolved and dispersed to prepare a conductive layer coating solution. This coating solution was applied onto the substrate by a dipping method to form a conductive layer coating film. Then, using the removing apparatus shown in FIG. 5, the unnecessary coating film was removed with a conductive layer coating film removing solution (methanol / THF = 4/1 mass ratio, water content 0.6 mass%). Subsequently, it heat-cured and dried for 30 minutes at 140 degreeC, and formed the 15-micrometer-thick conductive layer.

SnO ₂ coated barium sulfate 10 parts Titanium oxide 2 parts Phenol resin 6 parts Silicon oil 0.001 part Methyl alcohol / methoxypropyl alcohol = 0.2 / 0.8 20 parts <Intermediate layer>
An intermediate layer coating solution was prepared by dissolving the following composition. This coating solution was applied onto the conductive layer by a dipping method to form an intermediate layer coating film. Then, the unnecessary coating film was removed with the intermediate | middle layer coating film removal liquid (methanol / THF = 4/1 mass ratio, moisture content 0.8 mass%) using the removal apparatus shown in FIG. Subsequently, it dried for 30 minutes at 100 degreeC, and formed the intermediate | middle layer whose film thickness is 0.5 micrometer.

N-methoxymethylated nylon 3 parts Copolymer nylon 3 parts Methyl alcohol 65 parts N-butyl alcohol 30 parts <Charge generation layer>
The following composition was dispersed in a sand mill using glass beads having a diameter of 1 mm for 4 hours, and then 100 parts of ethyl acetate was added to prepare a charge generation layer coating solution. This coating solution was dip-coated on the intermediate layer to form a charge generation layer coating film. Thereafter, the unnecessary coating film was removed with a charge generation layer coating film removing solution (MEK / THF = 4/1 mass ratio, water content 0.8%) using the removing apparatus shown in FIG. Next, the film was dried at 100 ° C. for 30 minutes to form a charge generation layer having a thickness of 0.2 μm.

Oxytitanium phthalocyanine “CGM-1” (with strong peaks at 9.0 °, 14.2 °, 23.9 ° and 27.1 ° of Bragg angle (2θ ± 0.2 °) of CuKα)
4 parts Polyvinyl butyral "ESREC BM2" (manufactured by Sekisui Chemical Co., Ltd.) 4 parts Cyclohexanone 60 parts <Charge transport layer>
The following composition was dissolved to prepare a coating solution for a charge transport layer. This coating solution was applied onto the charge generation layer by a dipping method to form a charge transport layer. Then, the unnecessary coating film was removed with the charge transport layer coating film pool removal liquid (THF, water content 0.5 mass%) using the removal apparatus shown in FIG. Next, the film was dried at 110 ° C. for 2 hours to form a charge transport layer having a film thickness of 25 μm, and “end part non-peeled photoreceptor 1” was produced.

CTM-3 8 parts CTM-4 2 parts BPZ type polycarbonate “Z-300” (manufactured by Mitsubishi Gas Chemical) 12 parts THF 60 parts methyl alcohol 40 parts

[Fabrication of edge-unpeeled photoreceptor 4]
<Substrate>
As the substrate, an aluminum drum subjected to Compass processing with Rz 1.6 μm was used.

<Intermediate layer>
An intermediate layer coating solution was prepared by dissolving the following composition. This coating solution was applied onto the substrate by a dipping method to form an intermediate layer coating film. Using the removing apparatus shown in FIG. 5, the unnecessary coating film was removed with an intermediate layer coating film removing solution (methanol, water content 0.9%). Subsequently, it was dried with hot air at 100 ° C. for 30 minutes to form an intermediate layer having a film thickness of 0.5 μm.

Polyamide resin “Amilan CM8000” (manufactured by Toray Industries, Inc.) 5 parts Methyl alcohol 95 parts <Charge generation layer>
The following composition was dispersed for 4 hours in a sand mill using φ1 mm glass beads to prepare a coating solution for a charge generation layer. This coating solution was applied onto the intermediate layer to form a charge generation layer coating film. Then, the unnecessary coating film was removed with the charge generation layer coating film removal liquid (MEK, water content 0.8%) using the removal apparatus shown in FIG. Next, the film was dried with hot air at 105 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.2 μm.

Hydroxygallium phthalocyanine crystal “CGM-2” (CuKα Bragg angle 2θ ± 0.2 ° is 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 °, 25.1 ° 4 parts polyvinyl butyral resin “BX-1” (manufactured by Sekisui Chemical Co., Ltd.) 2 parts cyclohexanone 80 parts <Charge transport layer>
The following composition was dissolved to prepare a coating solution for a charge transport layer. This coating solution was applied onto the charge generation layer to form a charge transport layer coating film. Then, using the removing apparatus shown in FIG. 5, the unnecessary coating film was removed with a charge transport layer coating film removing solution (THF / dioxolane = 1/1 mass ratio, water content 3.0 mass%). Next, the film was dried with hot air at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm.

CTM-3 9.2 parts BPZ type polycarbonate “Z-200” (manufactured by Mitsubishi Gas Chemical) 10 parts THF 75 parts Toluene 25 parts <Protective layer>
The following composition was dispersed in a sand mill for 66 hours, and further 20 parts of polytetrafluoroethylene fine particles (average particle size 0.18 μm) were added for dispersion for 2 hours. Thereafter, 30 parts of a thermosetting resol type phenolic resin “PL-4804” (manufactured by Gunei Chemical Industry Co., Ltd.) was dissolved as a resin component to prepare a protective layer coating solution. This coating solution was dip coated on the charge transport layer to form a protective layer coating film. Then, the unnecessary coating film was removed with the protective layer coating film accumulation removal liquid (methanol / ethanol = 1/1 mass ratio) using the removal apparatus shown in FIG. Next, the film was dried and cured at a temperature of 145 ° C. for 1 hour to form a protective layer (charge injection layer) having a film thickness of 6 μm, and “end portion non-peeled photoreceptor 4” was produced.

20 parts antimony-doped tin oxide ultrafine particles 20 parts surface treated with a fluorine-modified silane coupling agent “LS1090” (manufactured by Shin-Etsu Silicon Co., Ltd.) Surface treatment with methyl hydrogen silicon oil “KF99” (manufactured by Shin-Etsu Silicon Co., Ltd.) (Treatment amount 20%) antimony-doped tin oxide fine particles 30 parts ethyl alcohol 150 parts [Examples 1 to 7]
Using the stripping solution and stripping tape shown in Table 1, the stripping apparatus shown in FIG. 1 peeled up to 20 mm from the end of the substrate of “end-side unstripped photoreceptors 1 to 4” to prepare a photoreceptor.

  In addition, the following "wiping tapes 1-3" were used for the wiping tape.

<Wiping tape 1>
Product name "Charelia" (spunlace acrylic fiber nonwoven fabric: manufactured by Asahi Kasei Corporation)
<Wiping tape 2>
Product name "PS-13949" (139 mesh, satin weave: NBC Industrial Co., Ltd.)
<Wiping tape 3>
A carded blend of 60% by mass of unstretched polyethylene terephthalate fiber having a linear density of 0.56 mg / m and a fiber length of 38 mm and 40% by mass of stretched polyethylene terephthalate fiber having a linear density of 0.17 mg / m and a fiber length of 38 mm. A surface density of 60 g / m ² in which a directional fiber web and a cross fiber web formed by crossing unidirectional fiber webs formed in the same manner as the unidirectional fiber web with a cross layer are laminated at a mass ratio of 1: 4. Laminated fiber web.

[Comparative Examples 1-4]
Using the end face stripping solution and the wiping tape shown in Table 1, the stripping apparatus shown in FIG. 2 peeled up to 20 mm from the end of the substrate of the “end face unpeeled photoreceptor 1” to prepare a photoreceptor.

  Table 1 shows the end face non-peeled photoreceptor used in Examples 1 to 7 and Comparative Examples 1 to 4, the organic solvent of the end face stripping solution, the water content, and the type of tape.

[Evaluation]
<Peeling performance>
The peeled end of the photoreceptor was visually evaluated.

◎: Good with no peeling residue ○: It takes a little time for peeling, but no peeling residue is good ×: Poor with peeling residue

<Unevenness of peeled end surface>
The shape (unevenness) of the peeled end face of the photoreceptor was measured with a contact-type film thickness measuring machine.

A: Unevenness on the peeled end face is ± 20 μm
○: Concavities and convexities on the peeled end face are ± 20 μm to ± 40 μm
X: The unevenness of the peeled end face is ± 40 μm or more.

[Image evaluation]
A commercially available copying machine “Sitios 7165” (manufactured by Konica Minolta Co., Ltd.) was modified so that an image could be formed using the photoconductor produced above, and 100,000 sheets were printed.

<Image density unevenness>
The image density unevenness of the halftone portion caused by the variation in the distance between the photosensitive member and the developing roll caused by the defective removal of the unnecessary coating film at the end of the photosensitive member (the state where the coating film remains) was visually evaluated.

Evaluation Criteria A: No image density unevenness in the halftone part ○: Image density unevenness is slightly seen in the halftone part, but there is no problem in practical use. X: Image density unevenness is clearly seen in the halftone part, and there is a problem in practical use.

<Image cover>
Visual evaluation was made of the toner that passed through the scratches on the cleaning blade generated at the convex part at the coating film end and the image fog caused by the toner that slipped through the concave part. .

Evaluation criteria A: No occurrence of image fogging due to uneven portions at the coating film edge even after printing 100,000 sheets ○: There was no occurrence of image fogging due to the uneven portions at the coating film end, After printing 100,000 sheets, image fogging caused by uneven portions at the coating film edge was slightly observed. X: Image fogging caused by unevenness at the coating film edge portion was observed from the initial print, and this was a practical problem. Yes.

  Table 2 shows the evaluation results of peeling performance, unevenness of the peeling end face, uneven image density and image fog.

  From the results of Table 2, Examples 1 to 7 using the end face stripping solution according to the present invention had good stripping performance, no wiping residue, and the end face was uniform with little unevenness on the stripping end face.

  However, in Comparative Examples 1 to 4 using a stripping solution other than the present invention, wiping residue was generated, the unevenness of the stripping end surface was large, and the cross section was not smooth and was not aligned.

  In addition, the printed images formed using the photoconductors of Examples 1 to 7 using the stripping solution according to the present invention were satisfactory without causing problems due to the end surface peeling, but were peeled outside the present invention. The printed images formed using the photoreceptors of “Comparative Examples 1 to 4” using the liquid had image defects such as black spots and black lines due to end face peeling, which had practical problems.

It is the schematic which shows an example of the peeling apparatus using a wiping tape. It is sectional drawing of the coating-film edge part of a photoreceptor. It is the schematic which shows an example of the method of making a wiping tape contact a photoreceptor. It is a schematic diagram which shows the application pool of a base | substrate lower end part. It is sectional drawing which shows an example of the removal apparatus which removes a coating pool. 1 is a cross-sectional view illustrating an example of an electrophotographic image forming apparatus that forms an image using a photoreceptor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wiping tape 2 Pressure-contact roll 3 Photoconductor 40 Stripping liquid tank 50 Impregnation part to wiping tape of stripping liquid 8 Original winding roll 9 Winding roll

Claims (3)

A step of forming a film by applying a coating solution containing a photosensitive layer on a conductive substrate, a step of forming a coating film by drying the film formed by coating at 100 to 145 ° C., a coating film formed by drying In the method for producing an electrophotographic photosensitive member, which has a step of removing the coating film by peeling the coating film by contacting the end of the substrate with a wiping tape impregnated with a stripping solution.
The stripping solution has a boiling point of 200 ° C. or lower and a cyclic ether as a main solvent, and water is 0.5 to 9 . A method for producing an electrophotographic photoreceptor, comprising 0% by mass. The method for producing an electrophotographic photosensitive member according to claim 1, wherein the cyclic ether is tetrahydrofuran. The method for producing an electrophotographic photosensitive member according to claim 2, wherein the cyclic ether is dioxolane.

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