JP2009186603A - Coating film removing device and method for removing coating film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating film removing device that easily and accurately wipes and removes an excess coating film remaining on an outer or inner surface in an end part of a photoreceptor where a photosensitive coating film is formed, without influencing a coating film formed in other part. <P>SOLUTION: The coating film removing device 10 includes a removing member 27 on a base 26, for removing a part of a photosensitive coating film 13 formed on the surface of a cylindrical photoreceptor 11. The removing member 27 is disposed to be in contact with an end part of the surface of the photoreceptor 11; and a nozzle 36 of a supply pipe 38 to eject a solvent to dissolve the photosensitive coating film 13 to the inside is inserted into the inside of the removing member 27. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a photoconductor used in an electrophotographic image forming apparatus such as a copying machine, a printer, and a facsimile machine, and a coating film removing apparatus for removing a part of the photosensitive coating film formed on the photoconductor. The present invention relates to a method for removing a coating film.

  For example, as shown in FIG. 6D, the electrophotographic photoreceptor is formed by coating a photosensitive coating 13 on the surface of a conductive substrate 12 made of a cylindrical aluminum drum. As shown in FIG. 5, the photosensitive coating film 13 includes a charge generation layer 14 and a charge transport layer 15. For example, the entire conductive substrate 12 is immersed in the coating solution 16 as shown in FIG. Thereafter, as shown in FIG. 6B, the film can be formed by a dipping method that pulls up at a constant speed.

  According to the forming method, since the conductive substrate 12 is immersed in the coating solution 16, the photosensitive coating film 13 is formed on the entire surface of the conductive substrate 12. The photoreceptor 11 thus formed is incorporated into an electrophotographic image forming apparatus such as a copying machine or a printer, and powder toner is attached to the surface of the photoreceptor 11 to visualize the electrostatic latent image. . At this time, if the distance between the surface of the magnet roller and the photoconductor 11 changes, the thickness of the toner adhering to the magnet roller may fluctuate, resulting in variations in image density and image defects. Therefore, when the photoreceptor 11 is incorporated in the electrophotographic image forming apparatus, a developing gap roller is interposed between the left and right ends of the magnet roller and the photoreceptor 11 so that the distance between the surface of the magnet roller and the photoreceptor 11 changes. To prevent it from happening. However, when the developing gap roller is brought into direct contact with the photosensitive coating 13 on the left and right end faces of the photoreceptor 11, the photosensitive coating 13 in the contact portion with the developing gap roller may be gradually peeled off during use. For this reason, there is a possibility that the image quality is deteriorated due to a change in the distance between the surface of the magnet roller and the photoconductor 11, and the image quality is deteriorated due to black spots on the image due to the peeled photosensitive coating film 13.

  Moreover, in the method of pulling up after the conductive substrate 12 is immersed in the coating solution 16 as described above, the coating solution 16 is directed downward as shown in FIG. By flowing, the liquid reservoir 17 is generated at the lower end portion of the photoconductor 11, and the film thickness at the end portion varies. In order to prevent the formation thickness of the photosensitive coating film 13 from being varied, the photosensitive coating film 13 at both ends of the portion where the developing gap roller contacts is previously provided for the required width d as shown in FIG. It was only desired to remove it.

With respect to the removal of the photosensitive coating film, the following apparatuses and methods have been conventionally disclosed. For example, in the removal method using a solvent, a method in which a photoreceptor having a coating film formed in a solvent that dissolves the coating film is immersed (Patent Document 1), the solvent is sprayed with a nozzle, and a brush or sponge is used. A method of dissolving and removing a coating film with a removing member such as (Patent Documents 2 and 3) has been proposed. Patent Document 4 discloses a coating film removing apparatus and a method for wiping off an end portion of a photoreceptor on which a coating film is formed while pouring a solvent over a removing member such as a brush or a sponge. Yes.
JP-A-6-202352 JP-A-10-207084 JP 2000-275870 A JP 2002-278104 A

  However, even the apparatus and method disclosed in Patent Documents 1-3 are not sufficient to solve the above problems, and have the following problems. First, in an apparatus or method for immersing and removing a conductive substrate in a solvent for dissolving a coating film, unevenness may occur in the coating film due to fluctuations in the liquid level. Even the photosensitive coating film may be removed. Secondly, in the method in which the end of the photoconductor is rubbed and removed while spraying the solvent from the supply nozzle onto the sponge, which is the removal member of the coating film, the solvent ejected from the nozzle is other than the excess coating film. There is also a possibility that the photosensitive coating film may be scattered. Third, the solvent supply nozzle port may be volatilized and clogged, and the solidified solvent powder may be ejected and adhere to the end of the photoreceptor. Fourth, the positional relationship between the removal surface of the photoreceptor coating film and the removal member such as sponge is always the same position. There is a problem that the initial performance as a coating film cannot be maintained.

  Further, in Patent Document 4, a solvent supply nozzle is disposed on a removal member in contact with the end of the photoreceptor on which a coating film is formed. From this supply nozzle, the solvent is poured over the removal member. Therefore, when the solvent is supplied, there is a possibility that the film may be scattered on a portion of the coating film that does not need to be removed. For this reason, it has been difficult to remove the coating film so as to limit it to a necessary portion without affecting other portions.

  Therefore, the object of the present invention is to easily apply the excess coating film remaining on the outer surface or inner surface of the end portion of the photoreceptor on which the photosensitive coating film is formed, to the coating film formed on other portions. And it is providing the coating-film removal apparatus and coating-film removal method which can be wiped off correctly.

  In order to solve the above problems, the coating film removing apparatus of the present invention is a coating film removing device in which a removing member for removing a part of the photosensitive coating film formed on the surface of the cylindrical photoreceptor is provided on the base. In the apparatus, the removal member is disposed so as to be in contact with an end portion of the surface of the photoreceptor, and a distal end portion of a supply pipe for discharging a solvent for melting the photosensitive coating film to the inside is a removal member. It is inserted in the inside.

  Further, the coating film removing method of the present invention is a coating film removing method for removing an excess photosensitive coating film by bringing an elastic body containing a solvent into contact with the surface of the photoreceptor, and the elastic body on the surface of the photoreceptor. During the contact, the solvent is continuously supplied to the elastic body.

  According to the coating film removing apparatus according to the present invention, a removing member is provided so as to be in contact with the surface of the end portion of the photoreceptor on which the photosensitive coating film is uniformly formed, and a solvent supply pipe for melting the photosensitive coating film Since the tip portion of is inserted into the inside of the removing member, the solvent can be permeated from the inside of the removing member so as not to scatter. Thus, the end portion of the photoreceptor can be wiped and removed with high accuracy while supplying the solvent to the removing member. Further, when wiping and removing, the solvent is not applied to portions other than the end portion of the photoreceptor, and therefore, it is possible to effectively prevent peeling and deterioration of the photosensitive coating film in portions that do not need to be removed.

  In addition, according to the method for removing a coating film according to the present invention, while the elastic body is in contact with the surface of the photoconductor, the solvent is continuously supplied to the elastic body, so that the excess photosensitive coating film can be formed in a short time. It can be removed cleanly without leaving.

  Hereinafter, embodiments of a coating film removing apparatus and a coating film removing method according to the present invention will be described in detail with reference to the accompanying drawings. The coating film removing apparatus and the coating film removing method of the present invention are mainly intended for an electrophotographic photoreceptor 11 as shown in FIG. The photoreceptor 11 is formed by coating a photosensitive coating 13 on the surface of a conductive substrate 12 made of a cylindrical aluminum drum. As shown in FIG. 5, the photosensitive coating 13 includes a charge generation layer 14 and a charge transport layer 15 and is formed by an immersion method. The photosensitive coating film 13 may be provided with an undercoat layer, an intermediate layer, a surface protective layer, and the like. In addition to the structure shown in FIG. 5, the structure of the photoconductor 11 includes a structure in which a charge generation layer is provided on a charge transport layer, a single layer in which a charge generation material and a charge transport material are mixed and dispersed, and the like. is there.

  The coating film removing apparatus 10 according to the first embodiment shown in FIGS. 1 and 2 includes a holding mechanism 21 for holding the photosensitive member 11 in a vertical direction, and the photosensitive member 11 held by the holding mechanism 21. And a removing mechanism 22 for wiping off and removing the excess coating film 18 formed on the end portion.

  The holding mechanism 21 includes a gripping portion 23 that grips the upper end portion of the photoconductor 11, and an elevating drive unit (not shown) for lowering and raising the gripping portion 23 toward the removal mechanism 22. ing. The gripping part 23 is integrally formed with a disc-shaped gripping plate 24 that is brought into close contact with the inner diameter of the conductive base 12 and a suspension part 25 that is suspended by an elevating drive part.

  The removal mechanism 22 includes a solvent recovery tank 40, a base 26 rotatably disposed on the recovery tank 40, a removal member 27 provided on the base 26, and a solvent on the removal member 27. And a solvent supply unit 28 for supplying a dehalogenated solvent. The base 26 is provided with an inner coating film removing member 31 near the center of the upper surface and an outer coating film removing member 32 near the outer peripheral surface. As shown in FIGS. 2 and 3, the inner surface coating film removing member 31 is for contacting the inner surface of the photoreceptor 11 and for wiping and removing the photosensitive coating film in the contacted portion. It is formed of a porous elastic body (sponge) made of a cylindrical polyurethane resin or melamine resin. The inner surface coating film removing member 31 is attached to the upper surface of the base 26 in a state where the center portion is pierced by the pin 33. The outer surface coating film removing member 32 is for making contact with the outer surface of the photoconductor 11 and wiping and removing the photosensitive film of the contacted portion. A concave shape having a radius of curvature corresponding to the diameter of the photoconductor 11 is formed so that the outer surface is in close contact. The outer surface coating film removing member 32 is also formed of a sponge made of the same material as the inner surface coating film removing member 31. The inner surface coating film removing member 31 and the outer surface coating film removing member 32 can be replaced with ones having different radii of curvature and thickness according to the shape and size of the photoreceptor 11 to be processed.

  As shown in FIG. 1, solvent discharge ports 35 are provided on the lower surfaces of the inner surface coating film removing member 31 and the outer surface coating film removing member 32, respectively. The discharge port 35 is provided at the tip of a nozzle 36 extending from the inside of the base 26, and directs the solvent supplied from the solvent supply unit 28 toward the inside of the inner surface coating film removing member 31 and the outer surface coating film removing member 32. In this way, the solvent can be directly discharged and the solvent can easily penetrate inside. One or a plurality of the nozzles 36 are provided according to the shape and size of the inner surface coating film removing member 31 and the outer surface coating film removing member 32.

  The solvent supply unit 28 includes a solvent storage tank 37, a supply pipe 38 extending from the storage tank 37 to the inside of the base 26, and a recovery pipe connected to the storage tank 37 from the recovery tank 40 in which the base 26 is disposed. 41 and a pump 39 with a filter. The solvent for melting the photosensitive coating film is stored in the storage tank 37 in advance, and is sucked up by the pump 39 from the storage tank 37 and is discharged from the discharge port 35 of each nozzle 36 to the inner surface coating film removing member 31 and the outer surface. It is supplied to the inside of the coating film removing member 32. Further, the solvent discharged to the outside from the inner surface coating film removing member 31 and the outer surface coating film removing member 32 by the cleaning is temporarily stored in the recovery tank 40 and returned to the storage tank 37 through the recovery pipe 41.

  Thus, the solvent sucked up from the storage tank 37 through the pump 39 is supplied from the discharge port 35 through the supply pipe 38 and the nozzle 36, and the inner surface coating film removing member 31 and the outer surface coating film removing member 32 are swollen. Let Further, in this state, the base 26 is rotated by a driving source (not shown), so that the surfaces of the inner surface coating film removing member 31 and the outer surface coating film removing member 32 are inside the photoconductor 11 as shown in FIG. The excess photosensitive coating film is removed while being rubbed along the peripheral surface and the outer peripheral surface.

  Next, a coating film removing method using the coating film removing apparatus 10 will be described. As shown in FIG. 1, the photosensitive member 11 on which the photosensitive coating film 13 is formed is lowered toward the upper surface of the base 26 via a lifting drive unit (not shown) in a state where the photosensitive member 11 is suspended and held by the gripping unit 23. The lowering is performed by shifting the inner surface and the outer surface of the photoconductor 11 in the left-right direction so that the inner surface coating film removing member 31 and the outer surface coating film removing member 32 are not in contact with each other. As shown in FIG. 3, after the inner surface coating film removing member 31 and the outer surface coating film removing member 32 are swollen by the solvent supplied from the solvent supply unit 28, the photoconductor 11 is placed on the base 26. In contrast, the inner surface and the outer surface of the end portion of the photoconductor 11 are brought into contact with the inner surface coating film removing member 31 and the outer surface coating film removing member 32 by moving in the horizontal direction. During this contact, the solvent is continuously supplied to the inner surface coating film removing member 31 and the outer surface coating film removing member 32. In this state, the base 26 is rotated at least once to wipe off the excess coating film 18. In order to completely remove the excess coating film 18, it is preferable to rotate the base 26 three or more times. After the coating film removing operation is completed, the photosensitive member 11 is returned to the original horizontal position, and is lifted and collected by the holding mechanism 21, and a photosensitive member to be processed next is attached. During this time, a new solvent is sucked up from the solvent storage tank 37, and the solvent is supplied from the respective discharge ports 35 to the inner surface coating film removing member 31 and the outer surface coating film removing member 32, thereby removing the adhering to the surface of the removing member. Wash away the residue of the used photosensitive film. By repeating such a cycle, a plurality of photoconductors can be processed continuously.

  FIG. 4 shows a configuration example of the coating film removing apparatus 50 in the second embodiment. In this coating film removing device 50, the front end (nozzle) 56 of the supply pipe 38 is inserted in the longitudinal direction inside the inner surface coating film removing member 51 and the outer surface coating film removing member 52, and a plurality of discharges are formed on the surface of the nozzle 56. An outlet 55 is provided. Further, each discharge port 55 is provided so as to face the outer surface of the inner surface coating film removing member 51 and the outer surface coating film removing member 52 with which the photoconductor 11 is in contact. Thus, by inserting the nozzle 56 into the inner surface coating film removing member 51 and the outer surface coating film removing member 52, the nozzle 56 is directed toward the portion where the surplus coating film 18 formed at the end of the photoreceptor 11 comes into contact. Thus, the solvent can be discharged, and the removal efficiency can be further improved. Note that the configuration of the holding mechanism 21 that holds the photosensitive member 11, the base 26, and the solvent supply unit 28 is the same as that of the coating film removing apparatus 10 of the first embodiment, and thus the same reference numerals are used for the same members. The detailed description is omitted by using.

  In the above embodiment, the photoconductor 11 is fixed and the base 26 is rotated. However, a configuration in which a rotation drive source is provided on the holding mechanism 21 side and the photoconductor 11 is rotated in a suspended state. It is also possible to make it. Further, by arranging a plurality of the holding mechanisms 21 and the removing mechanisms 22, it is possible to perform a film removing operation for a plurality of photosensitive members at a time.

  In the above embodiment, the photosensitive film 11 is formed on the surface of the photosensitive body 11 by dip coating using the aluminum conductive substrate 12 having an outer diameter of 30 mm, an inner diameter of 28.4 mm, and a length of 254 mm as a base. And the example in the case of removing the coating-film part (excess coating film) of about 20 mm of inner and outer periphery of a lower end part is shown below. Here, in the state in which the photosensitive member 11 is suspended and fixed by the holding mechanism 21, the excess coating film (about 20 mm from the bottom) at the lower end is removed. Moreover, melamine foam sponge was used for the inner surface coating film removing member 31 and the outer surface coating film removing member 32. At this time, the base 26 on which the inner surface coating film removing member 31 and the outer surface coating film removing member 32 were fixed was 30 rpm, and the solvent was tetrahydrofuran of 20 ml / min. The lower end of the photoconductor 11 is lowered by an elevating mechanism at a speed of 1 mm / second, the lower end of the photoconductor 11 is stopped at about 10 mm from the base 26, the base is rotated for 10 seconds, and the coating surface and the coating are applied. The film removing member was rubbed. Thereafter, the photosensitive member 11 was lifted at a speed of 1 mm / second, removed from the gripping portion 23, and subjected to a drying process, whereby the photosensitive member 11 in which the end portion of the photosensitive coating film was removed as set could be obtained. .

  In Example 1, a photoconductor as set could be obtained in the same manner as in Example 1 except that the inner surface coating film removing member 31 and the outer surface coating film removing member 32 were replaced with urethane foam sponge.

  There was no coating film residue on the inner and outer surfaces of the lower end of the photoconductors obtained by the processes of Example 1 and Example 2, and a very good photoconductor was obtained.

  As described above, in the coating film removing apparatus and the coating film removing method of the present invention, unnecessary coatings are present on the inner and outer surfaces of the lower end portion of the cylindrical photoreceptor on which the photosensitive coating film is formed by dip coating. The surplus coating film surface can be removed accurately and efficiently in a desired dimension range. As a result, productivity can be easily improved, and a large number of photosensitive members that do not cause problems such as image defects can be provided at low cost.

It is sectional drawing which looked at the coating-film removal apparatus of 1st Embodiment which concerns on this invention from the side surface direction. It is sectional drawing seen from the upper surface direction of the said coating-film removal apparatus. It is sectional drawing which shows the removal state of the excess coating film by the said coating-film removal apparatus. It is sectional drawing which looked at the coating-film removal apparatus of 2nd Embodiment which concerns on this invention from the side surface direction. It is sectional drawing which shows the structure of the photosensitive coating film formed in a photoreceptor. It is process drawing which shows the formation process of a photosensitive coating film.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Coating film removal apparatus 11 Photoconductor 12 Conductive substrate 13 Photosensitive coating film 14 Charge generation layer 15 Charge transport layer 16 Coating liquid 17 Liquid reservoir 18 Excess coating film 21 Holding mechanism 22 Removal mechanism 23 Gripping part 24 Gripping plate 25 Hanging part 26 base 27 removal member 28 solvent supply part 31 inner surface coating film removal member 32 outer surface coating film removal member 32a inner surface 33 pin 35 discharge port 36 nozzle 37 storage tank 38 supply pipe 39 pump 40 collection tank 41 collection pipe 50 coating film removal Equipment 51 Inner surface coating film removal member 52 Outer surface coating film removal member 55 Discharge port 56 Nozzle

Claims (7)

A coating film removing apparatus provided on a base with a removing member for removing a part of a photosensitive coating film formed on the surface of a cylindrical photoreceptor,
The removal member is disposed so as to contact an end portion of the surface of the photoreceptor, and a distal end portion of a supply pipe for discharging a solvent for melting the photosensitive coating film is inserted into the removal member. A coating film removing apparatus characterized by comprising: 2. The coating film removing apparatus according to claim 1, wherein the removing member includes an inner surface coating film removing member that contacts an inner surface of an end portion of the photoconductor and an outer surface coating film removing member that contacts an outer surface of the end portion of the photoconductor. . 2. The coating film removing apparatus according to claim 1, wherein the removing member rotates while being brought into contact with an end portion of the photoconductor, while the solvent is supplied from a leading end portion of the supply pipe. The coating film removing apparatus according to claim 1, wherein the removing member has a curvature shape corresponding to a diameter of the photoreceptor. The said removal member is a coating-film removal apparatus of Claim 1 currently formed with the porous elastic body which consists of a polyurethane resin or a melamine resin. A holding mechanism for vertically holding a cylindrical photosensitive member on which a photosensitive coating film is formed;
In a coating film removing apparatus provided with a removal mechanism that removes the photosensitive coating film at the end of the photoreceptor held by the holding mechanism,
The removal mechanism includes a recovery tank for recovering the solvent, a base disposed in the recovery tank, a coating film removal member provided on the base and in contact with an end of the photoreceptor, A coating film removing comprising: a supply pipe for supplying a solvent from a base to the removal member; and a discharge port provided at a distal end portion of the supply pipe for directly discharging the solvent into the removal member apparatus. In the coating film removing method for removing the excess photosensitive coating film by bringing an elastic body containing a solvent into contact with the surface of the photosensitive body,
A method of removing a coating film, characterized in that a solvent is continuously supplied to the elastic body while the elastic body is in contact with the surface of the photoreceptor.

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