JP2001056575A - Method and device for removing coated film at end part of electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for easily and surely removing an unnecessary coated film sticking at the end part of the electrophotographic photoreceptor used for an electrophotographic recording system, etc., so that products of high quality can be obtained. SOLUTION: As for a conductive substrate 4 as the substrate of the electrophotographic photoreceptor, an under coat layer is formed on the outer surface of the substrate 4, thereafter, the resultant substrate 4 is dried in a state where the cylindrical part 2 of a metal jig frame 1 whose temperature is lower than that of the substrate 4 is inserted into the upper and lower ends by an appropriate length. And then, the metal jig frame is detached, and the conductive substrate is cooled down to a normal temperature, thereafter, the under coat layer at the end part of the conductive substrate is cleaned and removed. The coated film at the end part is easily and surely removed by setting the dimension of the metal jig frame 1 and the shape condition of the frame 1 to be desirable ones.

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 removing an end coating film of an electrophotographic photoreceptor, and more particularly to a method for removing an undercoat layer and a photosensitive layer from the bottom on the outer surface of a cylindrical conductive substrate. The present invention relates to a removing method for removing a surplus coating film applied to an end of a cylindrical body of an electrophotographic photosensitive member, and a removing apparatus used for performing the removing method.

[0002]

2. Description of the Related Art The electronic photographic recording system is widely used as the most common photographic system. In this method, an electrostatic latent image formed on an electrophotographic photoreceptor is exposed with toner, and the toner is transferred to paper or a plastic film for copying, and then, if necessary, subjected to a fixing treatment to obtain a desired copy. Is a way to get This electrophotographic photoreceptor, for example, in the case of an organic photoreceptor, is provided with a subbing coating on a conductive substrate in order to enhance adhesion and charge retention, and a charge generation coating and a charge transport coating thereon. Are sequentially laminated to form a photosensitive coating film. When these coating films are formed, the electrical properties of the photoconductor obtained by the physical properties of the coating solution, the coating conditions, the drying conditions of the coated material, and the like are slightly changed.

In the meantime, it is inevitable that some defective products are produced during the production of the electrophotographic photosensitive member, so that a high-quality copy cannot be obtained if the electrical characteristics of the electrophotographic photosensitive member are out of the specified range. . Also, if the electrophotographic photoreceptor is used many times for copying, the copying function will deteriorate due to the deterioration of the photoreceptor, so that the commercialized electrophotographic photoreceptor will not be discarded after being used many times. Absent. A part of the electrophotographic photoreceptor manufactured as described above is discarded, and its amount increases as the number of copying methods increases. However, among the electrophotographic photoreceptors that have been discarded, the conductive substrate is less likely to be damaged or deteriorated during the production of the photoreceptor or during copying, and the substrate is made of a high-purity material with high precision. It is self-evident that it is preferable if it can be recovered and reused. Even if the conductive substrate is damaged or deformed, it can be reused as a raw material.

[0004]

There are various methods for processing and reusing an electrophotographic photosensitive member.
For example, Japanese Patent Application Laid-Open Nos.
No. 81289. JP-A-4-33773
In JP-A No. 4 (Kokai) No. 4 (1999), a method is disclosed in which fine particles of ice are strongly sprayed to peel off the coating film, and then the conductive substrate is washed with water and dried. However, this method has a problem that the surface of the conductive substrate is damaged, and furthermore, there is a problem that the cost of the apparatus is high and setting of conditions is difficult. Japanese Patent Application Laid-Open No. 5-181289 discloses a method for removing an organic coating film with a treatment solution containing at least a carboxylic acid, a phenol compound and a ketone compound. However, this method has a problem that the coating film cannot be removed when the binder resin of the coating film of the undercoat layer is an insoluble resin, and that the processing time is long.

On the other hand, as a method of forming an electrophotographic photosensitive member, a dip coating method of forming a coating film by pulling up at a constant speed, other spray coating method, blade coating method, roller coating method, spinner coating method, vapor deposition Various methods such as a method and a method based on a combination thereof are used. However, in any of these methods, it is inevitable that a coating film is formed up to the outer peripheral surfaces at both ends of the cylindrical photosensitive member. If the coating is formed up to the end of the cylindrical photoreceptor, problems occur in the control of the toner removing blade and the attachment of the rotating belt of the cylindrical body on the mechanism of the copying machine and the like, and the members such as the developing press roller come into pressure contact. As a result, the coating film at the end is easily peeled off, and the deterioration of the blade function causes toner to be scattered in the copying machine, which affects the copy quality, resulting in image density unevenness, streaks, background stains, black spots, white spots, etc. Defects occur.

To solve the above problems, JP-A-1-143665 and JP-A-3-290664 disclose the above problems.
Publication. Japanese Patent Application Laid-Open No. 1-143665 discloses that a coating film at the end of a drum having a coating film formed on a peripheral surface is immersed in and removed from a solvent tank capable of dissolving tetrahydrofuran or the like a plurality of times, whereby the coating film is formed. A method of removing is disclosed. Japanese Patent Application Laid-Open No. Hei 3-290664 discloses a tape cleaning device in which a thin tape-like wiping tape such as a nonwoven fabric or a ribbon soaked in a solvent is run endlessly and the photosensitive member surface is wiped off. Are repeatedly washed, regenerated and reused. However, in the former case, since the non-woven resin tape (having a porous space) is insoluble, the removal is difficult when the binder resin of the undercoat coating is an insoluble resin. Problems such as scratches also occurred on the top, and in the latter case, the accuracy of dimensional removal of the coating due to meandering of the tape was inferior, and the critical part between the coating and the removed part became rough or convex, which was satisfactory. This method cannot be said to be a method of removing the surplus coating film at the end.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an unnecessary coating film at the end of a conductive substrate is reliably and quickly removed. An object of the present invention is to provide a method and an apparatus for removing a coating film on an electrophotographic photoreceptor which can be carried out relatively easily and inexpensively without deterioration in handling due to dew condensation.

[0008]

The above objects can be attained by the following method and apparatus for removing the coating film at the end of an electrophotographic photosensitive member according to the present invention. That is, the method for removing the end coating film of the electrophotographic photoreceptor according to claim 1 is a method for removing an electrophotographic photoreceptor in which an undercoat layer and a photosensitive layer are sequentially laminated from the bottom on the outer surface of a cylindrical conductive substrate. A method for removing a coating film applied to an end of a cylindrical body, comprising applying a subbing layer to an outer surface of a cylindrical conductive base, and then applying an undercoat layer to an end of the cylindrical conductive base. A step of drying with a metal jig inserted, and removing the metal jig and cooling the cylindrical conductive substrate to room temperature, and then lowering the end of the cylindrical conductive substrate. Washing and removing the coating layer.

Thus, in the method for removing the end coating film of the electrophotographic photosensitive member according to the first aspect, when drying the cylindrical conductive substrate on which the undercoat layer is applied, the cylindrical conductive substrate is dried. By inserting a metal jig into the end of the conductive base, heat can be released from the end of the cylindrical conductive base through the metal jig during this drying. It becomes possible, because the thermosetting of the undercoat layer at the end of the cylindrical conductive substrate is suppressed more than the undercoat layer in the range where the remaining image is formed,
When washing the excess undercoat layer at the end after cooling the cylindrical conductive substrate to room temperature, the undercoat is usually cured by heat and becomes difficult to elute and dissolve with an organic solvent. The layer is easily eluted and dissolved by the organic solvent without side effects, and is easily and reliably removed.

According to a second aspect of the present invention, there is provided a method of removing an end coating of an electrophotographic photosensitive member according to the first aspect. After applying the photosensitive layer to the outer surface of the base, drying the metal-made jig in a state where the metal jig is inserted into the end of the cylindrical conductive base, removing the metal jig, and removing the cylindrical jig. Cooling the conductive substrate to room temperature, and washing and removing the photosensitive layer at the end of the cylindrical conductive substrate.

Thus, in the method for removing the end coating of the electrophotographic photosensitive member according to the second aspect, the cylindrical conductive material is removed by the method for removing the end coating of the electrophotographic photosensitive member according to the first aspect. In addition to easily removing the excess undercoat layer at the edge of the substrate, the photosensitive layer is naturally dissolved and dissolved by an organic solvent by applying the same method when applying and drying the photosensitive layer. However, since the photosensitive layer is more easily removed, the removal of the excess coating film at the end of the cylindrical conductive substrate is improved as compared with the first embodiment.

In the above-described method for removing the coating film at the end of the electrophotographic photosensitive member, when the metal jig is inserted into the end of the cylindrical conductive substrate, the metal jig is removed. Although it is also possible to insert only at one end of the cylindrical conductive base,
It is also possible to insert at both ends. In particular, when metal jigs are simultaneously inserted into both ends of the cylindrical conductive substrate, the efficiency of removing the end coating film of the electrophotographic photosensitive member is improved, and the productivity is improved. Cost reduction is achieved.

Further, the inner peripheral surface of the cylindrical conductive base and the outer peripheral surface of the metal jig are both perfectly circular, and the metal conductive jig is attached to the end of the cylindrical conductive base. It is preferable that the inner peripheral surface of the cylindrical conductive base and the outer peripheral surface of the metal jig be substantially in close contact with each other when the jig is inserted. In this case, since the inner peripheral surface of the cylindrical conductive substrate and the outer peripheral surface of the metal jig are both perfectly circular, the metal jig is attached to the cylindrical conductive substrate. Insertion becomes easy, and the gap between the inner peripheral surface of the cylindrical conductive substrate and the outer peripheral surface of the metal jig is easily maintained uniformly. In addition, the inner peripheral surface of the cylindrical conductive base and the outer peripheral surface of the metal jig are substantially in close contact with each other, so that the metal jig is inserted into the end of the cylindrical conductive base. When drying in, heat is easily released from the end of the cylindrical conductive base via a metal jig, and the heat curing of the undercoat layer or the like at the end of the cylindrical conductive base is performed. The suppression effect is improved.

Here, it is desirable that the difference between the inner diameter of the cylindrical conductive substrate and the outer diameter of the metal jig be within 2 mm. From the viewpoint of releasing heat from the end of the cylindrical conductive base through the metal jig during drying, the inner diameter of the cylindrical conductive base and the outer diameter of the metal jig are determined. It is desirable to be as close as possible. However, if they are exactly matched, there arises a problem that it becomes difficult to insert a metal jig into the end of the cylindrical conductive substrate. Therefore, considering the ease of insertion of the metal jig, the cylindrical conductive base is set as an allowable range for sufficiently achieving the effect of releasing heat during drying from the end of the cylindrical conductive base. The difference between the inner diameter of the conductive substrate and the outer diameter of the metal jig was set to 2 mm or less, so that the inner peripheral surface of the cylindrical conductive substrate and the outer peripheral surface of the metal jig were almost in close contact. is there.

It is preferable that the length of insertion of the metal jig into the end of the cylindrical conductive base is 10 mm or more and 55 mm or less. When the insertion length is 10 mm or less, the state in which the metal jig is inserted into the end of the cylindrical conductive base becomes unstable, and the metal jig may fall out of the cylindrical conductive base. This is because there is a fear of doing so. Further, when the insertion length is 55 mm or more, the thermosetting does not stop at the end of the cylindrical conductive base and even the undercoat layer in the area where the image is formed. When washing and removing the surplus coating film at the end of the conductive substrate, the necessary coating film in the image forming range is also removed,
This is because image quality may not be maintained.

The metal jig is preferably made of a hollow cylindrical body from the viewpoint of material saving. In this case, it is preferable that the thickness of the metal jig is 1 mm or more. When the thickness of the metal jig made of a hollow cylindrical body is less than 1 mm, the action of releasing heat from the end of the cylindrical conductive base through the metal jig during drying is effective. This is because they are not sufficiently exhibited, and the thermosetting of the undercoat layer at the end of the cylindrical conductive substrate cannot be sufficiently suppressed.

When the metal jig is inserted into the end of the cylindrical conductive substrate and dried, the temperature of the metal jig is lower than the temperature of the cylindrical conductive substrate. Preferably, it is lower by 2 ° C. to 5 ° C. When the temperature difference between the metal jig and the cylindrical conductive substrate is smaller than 2 ° C., the heat is applied from the end of the cylindrical conductive substrate through the metal jig during drying. This is because the effect of dissipating the heat is not sufficiently exhibited, and the thermosetting of the undercoat layer at the end of the cylindrical conductive substrate is not sufficiently suppressed. Further, when the temperature difference between the two is greater than 5 ° C., the effect of releasing heat from the end of the cylindrical conductive base through a metal jig during drying is sufficiently exhibited, This is because, as a side effect, dew condensation occurs on the metal jig and its peripheral devices, which causes a problem that the operability of sticking the cylindrical conductive substrate is reduced.

According to a ninth aspect of the present invention, there is provided an electrophotographic photoreceptor having an end coating film removing apparatus, comprising: an undercoat layer and a photosensitive layer laminated on an outer surface of a cylindrical conductive substrate in order from the bottom. A removing device used for removing a coating film applied to an end of a cylindrical body of a photoreceptor, wherein an undercoat layer or an undercoat layer and a photosensitive layer are applied to an outer surface of a cylindrical conductive substrate. After that, when drying the cylindrical conductive substrate, a metal jig to be inserted into one end of the cylindrical conductive substrate, and a base table that holds the metal jig, It is characterized by having.

In the apparatus for removing an end coating film from an electrophotographic photosensitive member according to the ninth aspect, the undercoat layer or the undercoat layer and the photosensitive layer are coated on the outer surface of the cylindrical conductive substrate. By drying the cylindrical conductive base, by having a metal jig inserted into one end of the cylindrical conductive base,
Heat can be released from the end of the cylindrical conductive substrate during drying through the metal jig, and the thermosetting of the undercoat layer at the end of the cylindrical conductive substrate can be performed. Is suppressed, when the subsequent excessive undercoat layer at the end of the cylindrical conductive substrate is washed and removed, usually, it is hardened by heat and it is difficult to dissolve and dissolve with an organic solvent. The undercoat layer is easily eluted / dissolved and removed by the organic solvent without side effects.

Further, in the above-described apparatus for removing the end coating film of the electrophotographic photosensitive member, it is preferable that a plurality of metal jigs are arranged on the base table. In this case, since it is possible to simultaneously remove the excess coating film from the ends of the plurality of cylindrical conductive substrates, the efficiency of the work of removing the end coating film of the electrophotographic photosensitive member is improved. Thus, an improvement in productivity and a reduction in cost are achieved.

Further, such a device for removing the end coating film of the electrophotographic photosensitive member is provided as a set of two, and a pair of metal jigs of the set of the remover is provided with a cylindrical conductive substrate. It is preferable that both ends are inserted at the same time. In this case, since it is possible to simultaneously remove the excess coating film from both ends of the cylindrical conductive substrate, the efficiency of the work of removing the end coating film of the electrophotographic photosensitive member is improved, and the production is improved. Improvement in performance and reduction in cost are achieved.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Before describing the method and apparatus for removing a coating film from an electrophotographic photosensitive member of the present invention, the contents of the electrophotographic photosensitive member, the contents of the coating film, and the like will be specifically described. In addition, a laminated organic photoconductor will be described as an example of the electrophotographic photoconductor.

First, examples of the conductive substrate include metals such as aluminum, nickel, iron, copper, and gold, alloys containing the above metals as main components, polyesters such as polyethylene terephthalate, polycarbonate, phenolic resin, polyimide, glass, and the like. A metal thin film of aluminum, gold, silver or the like is formed on the above-mentioned insulating substrate, or a thin film of a conductive inorganic compound such as wire tin oxide or indium oxide is formed on the above-mentioned insulating substrate. Will be Further, the thickness of the conductive substrate is preferably 20 μm to 2.0 mm. If the thickness is 20 μm or less, the function of the support is reduced. If the thickness is 2.0 mm or more, the effect of the present invention is hardly obtained.

The undercoat layer is formed by forming a binder resin for forming an organic solvent-insoluble coating film such as a curable resin, or by dispersing an inorganic pigment in the binder resin. As the binder resin, alkyd resin, melamine resin, phenol resin, polyurethane resin, epoxy resin, benzoguanamine resin, casein and the like are used. Further, as the inorganic pigment, titanium oxide, alumina, zirconia, zinc oxide, silica, lead titanate and the like are used. These resins and pigments can be used alone or
Used as a mixture of more than one species. In addition, the thickness of the undercoat layer is 0.1.
It is generally from 1 μm to 5 μm, more preferably from 5 μm to 10 μm.

The photosensitive layer laminated on the undercoat layer comprises a charge generation layer and a charge transport layer, and the charge generation layer is a coating film formed mainly of an organic pigment which generates charges upon irradiation with light. This coating film is a ball mill, an attritor, a Glen mill, a sand mill, and a charge generating pigment alone or with a binder resin.
It is formed by coating a coating liquid formed by dispersing in a solvent with a dispersing machine such as a bead mill on a conductive substrate on which an undercoating film is formed, and has a thickness of 0.5 μm to 2 μm. Pigments used in the charge generation layer coating film include disazo-based, trisazo-based, azoxybenzene-based, benzimidazole-based, polycyclic quinone-based, perylene-based, indigoid-based, quinacridone-based, phthalocyanine-based, and methine-based pigments. An organic pigment with an advanced electronic system. The binder resin used here is generally a resin that forms an organic solvent-soluble coating film, and is one or a mixture of two or more thermoplastic resins such as polyvinyl butyral, polystyrene, silicon resin, and polyester. The solvent for the dispersion medium is cyclohexanone, tetrahydrofuran, methyl ethyl ketone, acetone, toluene, methanol or the like.

The other charge transport layer is a coating film for transporting charges generated in the charge generation layer, and is formed by applying a coating solution containing a charge transport substance and a binder resin on the charge generation coating film. It has a thickness of 20 μm to 40 μm. The charge transporting materials used in the charge transport coating include poly-N-vinylcarbazole compounds, pyrazoline compounds, α-phenylstilbene compounds, hydrazone compounds, diarylmethane compounds, triphenylamine compounds, and divinylbenzene. And known compounds such as fluorene-based compounds, anthracene-based compounds, oxadiazole-based compounds, and diaminocarbazole-based compounds. Also,
The binder resin for the coating film is generally a resin that forms an organic solvent-soluble coating film, and known resins such as polycarbonate, polyvinyl butyral, polyester, and poly-N-vinylcarbazole are used. The solvent is dichloromethane,
Known solvents such as tetrahydrofuran, dichloromethane, toluene, and ethyl methyl ketone are used.

By the way, the layered type organic photoreceptor is composed of three layers as described above, and the undercoat layer provided on the conductive substrate is hardly eluted and dissolved by an organic solvent, so It is difficult to remove the undercoat layer coating on the porous substrate. In contrast, the charge generation layer and the charge transport layer on the undercoat layer are easily eluted and dissolved by the organic solvent. Therefore, the biggest problem is how to separate the three-layer coating film from the conductive substrate.

As described above, in the method and apparatus for removing a coating film from an electrophotographic photosensitive member according to the present invention, an undercoat layer is formed in order to easily remove the edge after drying and forming the undercoat layer, which is the biggest problem. A metal jig piece plated to prevent corrosion of stainless steel, iron, nickel, iron, etc. is inserted at the rear end and dried while it is inserted. Provided is a method and an apparatus for reducing thermal curing of a layer coating film and removing an edge subbing layer coating film with an organic solvent without side effects. After the undercoat layer described above is provided on the cylindrical conductive substrate, the conductive jig is placed at the lower end or the lower end on the inner peripheral surface of the circumferential conductive substrate before the drying step of heat curing. After being transferred or inserted to the upper end and dried by a drying device, the coating film is removed.

Next, the specific structure of the coating film removing apparatus will be described. In the present embodiment, a metal jig piece 1 shown in FIGS. The metal jig piece 1 is composed of a cylindrical portion 2 and a base table 3 for supporting the same. The material is preferably the same material as that of the conductive base from the viewpoint of reducing relative thermal displacement, but it is not necessarily the same. It does not have to be. Although the cylindrical portion 2 is formed of a perfect circular cylinder in the drawing, the present invention is not limited to this. However, in general, the conductive substrate is a cylindrical body, and the same shape is preferable in terms of the effect of removing the coating film and the ease of manufacture. Base stand 3
Is formed in a flat plate shape, but preferably has a shape that can be easily mounted when the metal jig piece 1 is mounted on an automatic transfer device or the like. Further, in the present embodiment, two cylindrical portions 2 are arranged side by side, but may be one, or a plurality of cylindrical portions may be provided.

The cylindrical portion 2 of the metal jig piece 1 has an outer diameter d and a length L
, And is heated to T ° C. during use. When the inner diameter of the conductive substrate 4 shown in FIGS. 3 and 4 is D, the value of d is d = D−2δ, and δ is 0 to 1 mm. There is no gap between the conductive base 4 and the metal jig piece 1 when the metal jig piece 1 is inserted, and it is desirable that the metal jig piece 1 be in full contact. Therefore, it is desirable that δ = 0, but since it is practically difficult, δ = 0
Is 1 mm or less. If it is more than this, the contact property between the two is reduced, and the effect of removing the coating film is reduced.

The thickness t of the metal jig piece 1 needs to be 1 mm or more. If it is 1 mm or less, the mass function of the metal jig piece 1 is not transmitted, and it is confirmed that the coating film removing effect is extremely low in practice. The length L is preferably in the range of 10 mm to 55 mm. If the thickness is 10 mm or less, the supportability of the conductive substrate 4 by the metal jig piece 1 is poor, and if it is 55 mm or more, a portion of the conductive substrate 4 which is required to form a coating film may be removed.

FIGS. 3 and 4 show the state when the metal jig piece 1 is used. FIG. 3 shows the case where the metal jig piece 1 is inserted only at the lower end of the conductive base 4. Indicates a case where the metal jig pieces 1 are simultaneously inserted into the upper and lower ends so as to face each other. In this case, the temperature T of the metal jig piece 1 depends on the conductive substrate 4 to be inserted.
Is T1 (2 ° to 5 ° C.), where T1 is the temperature of T1. This is to prevent thermal curing during drying. It was confirmed that the coating film was hardly removed if there was no temperature difference from T = (T1-2) ° C. T = (T1-5) ° C.
Although the effect of removing the coating film is obtained as described above, the metal jig piece 1 and its peripheral devices are condensed, and the conductive base 4 and the metal jig piece 1 are sticky, and the operability is reduced.

Next, a method for removing a coating film on a conductive substrate will be described with reference to the flowchart of FIG. The upper portion of the conductive substrate 4 is chucked, and an undercoat layer is formed on the outer periphery of the conductive substrate by a dip coating method using a coating device (not shown) (step 100). In this case, the coating liquid at the maximum portion is wiped off with a sponge or the like to prevent the liquid from falling at the lower end of the undercoat layer. Next, the metal jig piece 1 is positioned and moved to a predetermined position manually or by a transporting means (automatic or the like), and the metal jig piece 1 is inserted into the lower end of the conductive base as shown in FIG. 3 (step 101). . Next, the whole is dried in this state (Step 102), and thereafter, the metal jig piece 1 is removed (Step 103), and the conductive substrate 4 is cooled to room temperature (Step 104). Next, the portion where the metal jig piece 1 is inserted is washed or the like by a coating film removing means to remove the coating film (step 105). The method of removing the edge coating film of the present invention is necessary at the time of drying after forming the undercoat layer, and may be performed at the time of forming the charge generating layer or at the time of drying after forming the charge generating layer and forming the charge transport layer. Has little effect. However, if the step is performed after the formation of the undercoat layer and before the drying, and further when the charge generation layer and the charge transport layer are dried, the removal of the end coating film is further improved. In the above description, a foaming sponge containing an organic solvent such as methyl ethyl ketone, dichloromethane, toluene, and tetrahydrofuran is used as the coating film removing means. These are used by a contact cleaning process.

[0034]

Next, an embodiment for explaining the above contents in more detail will be described. Of course, the present invention is not limited to the following contents. The percentages described below are based on weight. The conductive substrate of the electrophotographic photoreceptor used in the examples is
0.75mm wall thickness, outer diameter φ60mm, inner diameter φ58.5
A 352 mm long aluminum cylinder was used. The undercoat layer was a coating film composed of 20 parts of titanium oxide, 40 parts of alkyd resin, and 20 parts of melamine resin, and had a dry thickness of 6 μm. The undercoat layer was produced by coating a conductive substrate with a liquid obtained by dispersing a mixture of the above composition in 100 parts of methyl ethyl ketone. This coating liquid was prepared by dispersing and binding the raw materials in a ball mill for 24 hours. The coating solution is heat-treated at 130 to 140 ° C. for 0.5 hour after coating to make the organic solvent insoluble. A method for coating both the charge generation layer and the charge transport layer with the following coating solution The former has a dry film thickness of 1 μm, and the latter has a dry film thickness of 3 μm.
It was laminated by a method of sequentially coating the dried coating film so as to have a thickness of 0 μm. The coating liquid for forming the charge generation layer is prepared by dissolving 1 part of butyral resin (XYHL, manufactured by UCC) in 98 parts of a mixed solvent of cyclohexane and tetrahydrofuran (mixing ratio 7: 3), and dissolving the disazo compound represented by the following formula (1). Pigment 10
The mixture was added and dispersed by a ball mill for 72 hours.

[0035]

Embedded image

Further, the coating liquid for forming the charge transport layer is composed of a polycarbonate resin (manufactured by Teijin Limited: Panlite K-1300) and 10 parts of a charge transfer agent (hydrazone compound) represented by the following formula (2), and 80 parts of dichloromethane. And mixed.

[0037]

Embedded image

Next, basic conditions and evaluation items of the embodiment under the following conditions will be described.

(Basic conditions) The metal jig piece of the present invention was installed after forming the undercoat layer and before heat drying, and after drying, the metal jig piece was removed.
The drying was not performed when the charge generation layer and the charge transport layer were dried. Further, after the coating film was dried, the film was cooled with room temperature air for 6 minutes, and then the coating film was removed by an edge cleaning device. The edge cleaning device removes the edge coating film by rotating the edge while a sponge of Bridgestone Everlight Scott HR-30 is in contact with the edge and further moistened with a methyl ethyl ketone solvent.

Metal jig piece Material: SUS304 Outer shape: perfect circle Outer diameter: φ58.0 (inner diameter difference of conductive substrate φ0.5) Wall thickness: 2 mm Temperature: 17 ° C (temperature of conductive substrate 20 ° C) Insertion part: lower end Piece height: 40 mm

(Evaluation items) Removability of coating film (removability of undercoat layer) 1: Cannot remove the entire peripheral surface (no effect at all) 2: Partially removed 3: About half removed 4: Some parts have not been removed to some extent 5: All peripheral surfaces have been removed

Film removal time (rotation time of edge cleaning device) 1: 120 sec or more 2: 60 to 120 sec 3: 30 to 60 sec 4: 10 to 30 sec 5: 10

Dew condensation on metal jig piece 1: Dew formation (with conductive substrate attached) 3: Some dew condensation 5: No dew condensation

The contents of the first to thirteenth embodiments will be described. Example 1 An experiment was performed with the basic conditions as Example 1.

Example 2 An experiment was conducted in the same manner as in Example 1 except that the outer diameter was changed to φ57.5 (the difference in inner diameter of the conductive substrate was φ1.0).

Example 3 An experiment was performed in the same manner as in Example 1 except that the outer diameter was changed to φ56.5 (the difference in inner diameter of the conductive substrate was φ2.0).

Example 4 An experiment was conducted in the same manner as in Example 1 except that the thickness of the metal jig piece was set to 1 mm.

Example 5 An experiment was performed in the same manner as in Example 1 except that the thickness of the metal jig piece was set to 5 mm.

Example 6 An experiment was conducted in the same manner as in Example 1 except that the thickness of the metal jig piece was changed to 10 mm.

Example 7 An experiment was conducted in the same manner as in Example 1 except that the temperature of the metal jig piece was set at 18 ° C.

Example 8 An experiment was performed in the same manner as in Example 1 except that the temperature of the metal jig piece was set to 15 ° C.

Example 9 An experiment was conducted in the same manner as in Example 1 except that the metal jig piece was also inserted at the upper end.

Example 10 An experiment was carried out in the same manner as in Example 1 except that, after forming the charge generation coating film, the sample was transferred to a metal jig piece and dried.

Example 11 An experiment was performed in the same manner as in Example 1 except that the outer diameter was changed to φ54.5 (difference in inner diameter of conductive substrate was φ4.0).

Example 12 An experiment was performed in the same manner as in Example 1 except that the thickness of the metal jig piece was 25 mm.

Example 13 An experiment was conducted in the same manner as in Example 1 except that the temperature of the metal jig piece was set at 10 ° C.

The following Table 1 shows the evaluation results of the coating film removability, the coating film removal time, and the dew condensation state of the metal jig piece 1 in the above examples.

[0058]

[Table 1]

[0059]

As described above, according to the method and the apparatus for removing the end coating film of the electrophotographic photosensitive member according to the present invention, the following effects can be obtained. That is, according to the method for removing an end coating film of an electrophotographic photosensitive member according to claim 1, when the cylindrical conductive substrate coated with the undercoat layer is dried, the cylindrical conductive substrate is dried. By inserting a metal jig into the end of the tube, heat can be released from the end of the cylindrical conductive base through the metal jig during this drying. Since the thermosetting of the undercoat layer at the end of the cylindrical conductive substrate is suppressed more than the undercoat layer in the range where the remaining image is formed, the cylindrical conductive substrate was cooled to room temperature. When the surplus undercoat layer at the end is washed and removed later, it can be easily eluted and dissolved without side effects such as damaging the main body side by the organic solvent, and can be easily and reliably removed.

According to the method of removing the end coating film of the electrophotographic photosensitive member according to the second aspect, the cylindrical conductive material is removed by the method of removing the end coating film of the electrophotographic photosensitive member according to the first aspect. In addition to easily removing the excess undercoat layer at the edge of the substrate, the same method is applied to the application and drying of the photosensitive layer, so that the photosensitive layer at the edge of the cylindrical conductive substrate is removed. Is easily removed, so that the removal of the excess coating film at the end of the cylindrical conductive substrate can be improved as compared with the case of the first aspect.

According to the method for removing the end coating film of the electrophotographic photosensitive member according to the third aspect, when a metal jig is inserted into the end of the cylindrical conductive substrate, the metal jig is removed. Not only to insert the jig made of aluminum into only one end of the cylindrical conductive base,
Since it is also possible to insert the metal jig into both ends of the cylindrical conductive substrate at the same time, the efficiency of the work of removing the end coating film of the electrophotographic photosensitive member can be increased. To improve productivity and reduce costs.

Further, according to the method for removing the end coating film of the electrophotographic photosensitive member according to the fourth aspect, both the inner peripheral surface of the cylindrical conductive substrate and the outer peripheral surface of the metal jig are true. When the metal jig is inserted into the end of the cylindrical conductive base, the inner peripheral surface of the cylindrical conductive base and the outer peripheral surface of the metal jig are formed. The close contact makes it easier to insert the metal jig into the cylindrical conductive base, and facilitates the clearance between the inner peripheral surface of the cylindrical conductive base and the outer peripheral surface of the metal jig. When drying in a state where a metal jig is inserted into the end of the cylindrical conductive base, the metal can be held from the end of the cylindrical conductive base. The heat can be easily released through a jig made of a resin, and the effect of suppressing the thermosetting of the undercoat layer or the like at the end of the cylindrical conductive substrate can be improved.

According to the method for removing the end coating film of the electrophotographic photosensitive member according to the fifth aspect, the difference between the inner diameter of the cylindrical conductive substrate and the outer diameter of the metal jig is set within 2 mm. By making the metal jig easy to insert, the inner peripheral surface of the cylindrical conductive base and the outer peripheral surface of the metal jig are brought into close contact with each other, and Thus, the effect of releasing heat during drying from the end of the conductive substrate can be sufficiently achieved.

Further, according to the method for removing the end coating film of the electrophotographic photosensitive member according to the present invention, the insertion length when the metal jig is inserted into the end of the cylindrical conductive base is reduced. 10mm or more 5
By setting the thickness to 5 mm or less, the state in which the metal jig is inserted into the end of the cylindrical conductive substrate is stably maintained, and the range in which the thermosetting of the undercoat layer is suppressed is reduced to the cylindrical shape. When removing the excess coating film at the end of the cylindrical conductive base, the effect is not limited to the required undercoat layer in the image forming range, limited to the end of the conductive base. In addition, it is possible to prevent the deterioration of the image quality by removing even the coating film necessary for the image forming range.

Further, according to the method for removing the end coating film of the electrophotographic photosensitive member according to the present invention, the thickness of the metal jig made of a hollow cylindrical body is set to 1 mm or more, so that it can be dried at the time of drying. The effect of dissipating heat from the end of the cylindrical conductive base through the metal jig is sufficiently exerted to sufficiently cure the undercoat layer at the end of the cylindrical conductive base. Can be suppressed.

Further, according to the method for removing an end coating film of an electrophotographic photosensitive member according to the present invention, when drying is performed with a metal jig inserted into an end of a cylindrical conductive substrate. By setting the temperature of the metal jig to be lower by 2 ° C. to 5 ° C. than the temperature of the cylindrical conductive base, the end of the cylindrical conductive base is dried during drying. By sufficiently exerting the action of releasing heat through the metal jig, the thermosetting of the undercoat layer at the end of the cylindrical conductive substrate can be sufficiently suppressed, and the metal jig can be suppressed. It is possible to prevent the occurrence of dew condensation on the tool and its peripheral devices, thereby reducing the sticking operability of the tubular conductive substrate.

Further, according to the apparatus for removing an end coating film of an electrophotographic photosensitive member according to the ninth aspect, after the undercoat layer or the undercoat layer and the photosensitive layer are coated on the outer surface of the cylindrical conductive substrate. By having a metal jig inserted into one end of the cylindrical conductive base when drying the cylindrical conductive base, when drying through the metal jig, Heat can be released from the end of the cylindrical conductive substrate, and the thermosetting of the undercoat layer at the end of the cylindrical conductive substrate is suppressed. When the excess subbing layer at the end of the conductive substrate is removed by washing, it can be easily eluted and dissolved without side effects such as damaging the main body side with an organic solvent, and can be easily and reliably removed.

According to the apparatus for removing an end coating film of an electrophotographic photoreceptor according to the tenth aspect, a plurality of metal jigs are arranged on a base table to form a plurality of cylindrical bodies. It is possible to simultaneously remove the excess coating film from the end of the conductive substrate, thereby improving the efficiency of removing the end coating of the electrophotographic photosensitive member, thereby improving productivity and reducing cost. Reduction can be achieved.

Further, according to the apparatus for removing the end coating film of the electrophotographic photosensitive member according to the eleventh aspect, the apparatus for removing the end coating film of the electrophotographic photosensitive member is a set of two, and this one set is removed. A pair of metal jigs of the device are simultaneously inserted into both ends of the cylindrical conductive base, thereby removing excess coating film from both ends of the cylindrical conductive base. Can be performed at the same time, so that the efficiency of the work of removing the end coating film of the electrophotographic photosensitive member can be improved, and an improvement in productivity and a reduction in cost can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the entire structure of a metal jig piece of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a partial cross-sectional view showing a state where a metal jig piece of the present invention is inserted into a lower end of a conductive base.

FIG. 4 is a cross-sectional view showing a state where a metal jig piece of the present invention is inserted into upper and lower ends of a conductive base.

FIG. 5 is a flowchart for explaining the outline of the coating film removing method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal jig piece 2 Tubular part 3 Base stand 4 Conductive base

Claims (11)

[Claims] 1. A method for removing a coating film applied to an end portion of a cylindrical body of an electrophotographic photosensitive member in which an undercoat layer and a photosensitive layer are sequentially laminated from the bottom on an outer surface of a cylindrical conductive substrate. A step of applying the undercoat layer to an outer surface of the cylindrical conductive substrate, and then drying the metal conductive jig in a state where a metal jig is inserted into an end of the cylindrical conductive substrate. Removing the metal jig, cooling the cylindrical conductive substrate to room temperature, and washing and removing the undercoat layer at the end of the cylindrical conductive substrate. A method for removing an end coating film of an electrophotographic photoreceptor, comprising: 2. The method according to claim 1, wherein the photosensitive layer is coated on an outer surface of the cylindrical conductive substrate, and then the cylindrical conductive material is removed. A step of drying with the metal jig inserted into the end of the base; removing the metal jig; cooling the cylindrical conductive base to room temperature; Washing and removing the photosensitive layer at the end of the conductive substrate. A method for removing an end coating film of an electrophotographic photosensitive member, comprising: 3. The method for removing an end coating film of an electrophotographic photosensitive member according to claim 1, wherein the metal jig is inserted into an end of the cylindrical conductive substrate. And removing the end coating film of the electrophotographic photosensitive member by inserting the metal jig into one end or both ends of the cylindrical conductive substrate. 4. The method for removing an end coating film of an electrophotographic photosensitive member according to claim 1, wherein an inner peripheral surface of the cylindrical conductive substrate and the metal jig are removed. An outer peripheral surface thereof is formed in a perfect circle, and an inner peripheral surface of the cylindrical conductive base is inserted in a state where the metal jig is inserted into an end of the cylindrical conductive base. Wherein the outer peripheral surface of the metal jig is substantially in close contact with the outer peripheral surface of the metal jig. 5. The method according to claim 4, wherein the difference between the inner diameter of the cylindrical conductive substrate and the outer diameter of the metal jig is 2 mm. A method for removing an end coating film of an electrophotographic photoreceptor, wherein 6. The method for removing an end coating film of an electrophotographic photosensitive member according to claim 1, wherein the metal jig is inserted into an end of the cylindrical conductive substrate. A method for removing an end coating film of an electrophotographic photoreceptor, wherein an insertion length of the electrophotographic photosensitive member is 10 mm or more and 55 mm or less. 7. The method for removing an end coating film from an electrophotographic photosensitive member according to claim 1, wherein the metal jig is a hollow cylindrical body, and has a thickness of 1 mm.
mm or more, a method for removing an end coating film of an electrophotographic photoreceptor. 8. The method for removing an end coating film of an electrophotographic photosensitive member according to claim 1, wherein the metal jig is inserted into an end of the cylindrical conductive substrate. The temperature of the metal jig is 2 ° C. to 5 ° C. lower than the temperature of the cylindrical conductive base when drying in the dried state.
A method of removing an end coating film of an electrophotographic photoreceptor, wherein 9. When removing a coating film applied to an end portion of a cylindrical body of an electrophotographic photosensitive member in which an undercoat layer and a photosensitive layer are sequentially laminated from the bottom on the outer surface of a cylindrical conductive substrate. A removing device used for applying the undercoat layer or the undercoat layer and the photosensitive layer to an outer surface of the cylindrical conductive substrate, and then drying the cylindrical conductive substrate. A metal jig inserted into one end of the cylindrical conductive base; and a base table for holding the metal jig. Coating removal equipment. 10. The electrophotographic photoreceptor according to claim 9, wherein a plurality of the metal jigs are arranged on the base. A device for removing the coating film at the end of the photoconductor. 11. The apparatus for removing an end coating film of an electrophotographic photosensitive member according to claim 9 or 10, wherein said pair of metal jigs of said one set of removing apparatuses are said cylinders. An apparatus for removing an end coating film of an electrophotographic photosensitive member, wherein the device is inserted into both ends of a body-shaped conductive substrate at the same time.