JP2003098694A - Device for peeling photosensitive layer of electrophotographic photoreceptor and method of peeling photosensitive layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of peeling a photosensitive layer without flawing and damaging a substrate of even a photoreceptor of which at least one layer includes a curing layer. SOLUTION: This device for peeling the photosensitive layer of the electrophotographic photoreceptor is a device for peeling the photosensitive layer using an ultrasonic chamber to be used in peeling the photosensitive layer of the electrophotographic photoreceptor having the layer including inorganic fillers by irradiating the photoreceptor with ultrasonic waves while immersing the photoreceptor into an organic solvent, in which the surface including the surface to perform ultrasonic oscillation exists at a base surface and has a groove of >=5 mm in width and >=5 mm in depth around the surface to perform the ultrasonic oscillation or the surface inclusive of the surface to perform the ultrasonic oscillation projects by >=1 cm from its circumference.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for regenerating a substrate of an electrophotographic photosensitive member, and is applied to a method for removing a coating film.

[0002]

2. Description of the Related Art As a known technique for regenerating a substrate of an electrophotographic photoreceptor, the undercoat layer is regenerated by removing the coating film of a cylindrical electrophotographic function-separated type organic photoreceptor having a thermosetting resin. A centerless type cylindrical polishing apparatus, wherein a work rest supporting a work piece of the centerless type cylindrical polishing apparatus is brought into rotational contact with rollers, and a work piece is provided between an adjusting wheel and a roller type work rest that provide rotational drive. A centerless-type cylindrical polishing apparatus having a pressing roller for pressing is disclosed in JP-A-2000-20302.
It is described in Japanese Patent Publication No. In addition, when the laminate on the photoreceptor is removed and the substrate is reused from the photoreceptor obtained by laminating at least the undercoat layer and the photosensitive layer on the substrate, the laminate is swollen at once with a stripping solution. After peeling or by dissolving and removing the upper photosensitive layer, the undercoat layer is swollen and peeled by the peeling liquid to expose the substrate surface, and then a rubbing treatment with a member impregnated with a cleaning liquid A method of regenerating a substrate for a photoconductor is described in JP-A-2000-221704. In addition, manufacturing of an organic electrophotographic photoreceptor manufactured by forming an organic functional material film on a conductive substrate, defective product of functional material film generated in inspection process, defective product, or used product In the method of regenerating a conductive substrate from a life product, a defective product, a damaged product or a life product is obtained by the following equation, where water content x weight% and bath temperature y ° C. are y> 3x + 2.
It is possible to remove the organic functional material film from the conductive substrate by immersing it in an N-methylpyrrolidone bath satisfying the relationship represented by No. 5 to dissolve and remove it.
No. 67 publication. Also, make an incision in the coating film of the photoconductor with a coating film cutting device, and immerse the photoconductor with the cut film in the coating film separation water bath that stores water at a constant temperature as the coating film separating agent for a certain period of time. Then, by separating the coating film from the conductive substrate, it is possible to reliably remove the coating film having the subbing layer that is difficult to elute or dissolve in an organic solvent without causing scratches or the like on the conductive substrate surface of the photoreceptor, It is described in JP-A-2000-275868. Further, the photosensitive layer and the subbing layer are swollen by immersing the photoconductor in a dipping swelling stripping solution, and then the stripped device holds one end of the swollen photosensitive layer and the subbing layer and strips them off in a spiral shape Can be removed by means of
No. 65 publication. Further, the method for removing an organic film of an organic photoreceptor is characterized in that an organic film formed on a substrate is treated with a treatment liquid containing at least a carboxylic acid, a phenol compound and a ketone compound,
It is described in JP-A-5-181289 that a reusable organic photoreceptor regenerating substrate can be obtained by this method. Further, in an electrophotographic photosensitive member formed by sequentially laminating at least an undercoat layer and a photosensitive layer on a substrate, only the photosensitive layer of the used electrophotographic photosensitive member is removed by melting, cutting or peeling, and the used electrophotographic Japanese Patent Application Laid-Open No. 5-341537 discloses a method for reproducing an electrophotographic photosensitive member, which comprises forming a photosensitive layer again on the undercoat layer of the photosensitive member. Further, the electrophotographic photosensitive member having a photosensitive layer provided on the surface of the substrate via an undercoating layer containing a polyamide resin is immersed in water or moistened in a high humidity atmosphere, and then the photosensitive layer is removed from the surface of the substrate. Peeling together with the undercoat layer is described in JP-A-6-43663. Also, after the OPC drum having a photosensitive layer formed on the surface of a stainless steel substrate having a thickness of 0.4 mm or more is used, the photosensitive layer is dissolved and removed, and the photosensitive layer is formed again to form a new OPC. When it is used as a drum and a cured undercoat layer is formed on the surface of a substrate, it is necessary to dissolve and remove only the photosensitive layer on the undercoat layer.
No. 8 publication. Further, it is characterized by including an oxidative decomposition step of treating the undercoat coating film remaining on the conductive substrate after the removal of the photosensitive coating film with an oxidizing acid, using an apparatus of the same step and a substrate after the treatment with the oxidizing acid. An electrophotographic substrate regenerating device from an electrophotographic photoreceptor comprising a device for impregnating an undercoating film with an organic solvent and a water washing device for removing the undercoating film after treatment by mechanical external force and washing the substrate. , And a device for regenerating a conductive substrate from an electrophotographic photosensitive member, which is obtained by removing the device for impregnating an organic solvent from the above device, is described in JP-A-8-146623. Further, the conductor and the photoconductor formed by the polycarbonate of the photoconductor drum are removed by the linear beam of the TEA-CO ₂ laser, and at the same time, the remaining lowermost insulator is removed by the linear beam of the excimer laser. This is described in JP-A-9-146287. Further, from an OPC drum having a photosensitive layer formed on the surface of a stainless steel pipe substrate having a thickness of 0.3 mm or more, only this photosensitive layer is removed by jet collision of particles such as melamine alkyd resin onto this drum. Japanese Unexamined Patent Publication No. 9-179326 describes a process of obtaining a stainless steel pipe substrate and forming a photosensitive layer on the surface of the substrate to obtain an OPC drum. An organic solvent is supplied to the surface of the woven fabric, and the woven fabric containing the organic solvent is contacted or pressed against all or part of the peripheral surface of the electrophotographic photoreceptor to form it on the electroconductive substrate of the electrophotographic photoreceptor. The conductive layer, undercoat layer, photosensitive layer, and other coatings that have been removed are removed, and the woven fabric from which the coating film residue has been removed contains an organic solvent, and a brush is applied to scrape the coating film residue off the woven fabric. A method for removing a coating film from an electrophotographic photosensitive member is characterized in that the cleaning operation is repeatedly performed.
No. 75 publication. In addition, a step of subjecting the organic photoelectric drum having the organic photosensitive layer formed on the surface of the stainless steel drum substrate to a high temperature heating treatment at 600 ° C. to 1200 ° C. to remove an unnecessary organic photosensitive layer from the surface of the pipe substrate,
And a step of forming a new organic photosensitive layer on the surface of the drum substrate from which the unnecessary organic photosensitive layer is removed.
No. 0-177254. Provided is a removal solution for removing the outer layer of the base material in one step from an OPC drum formed by adhering the outer layer of the base material including a silane coupling layer, a charge generation layer, and a charge transfer layer on an aluminum base. It is described in JP-A-10-213911 that the removing liquid is a mixed liquid of an organic solvent and water to which 0.1 to 3% of a carboxylic acid is added. Further, the photosensitive layer is removed from a used OPC drum having a photosensitive layer on a conductive substrate by using a solvent containing an aprotic polar solvent having a dielectric constant of 20 or more and a dipole moment of 3 or more. And then washed with purified water,
It is a method of regenerating an OPC drum to form a new photosensitive layer again, and it is preferable to use dimethyl sulfoxide as the aprotic polar solvent, and dimethyl sulfoxide as the solvent containing the aprotic polar solvent. It is preferable to use a mixture of a solvent and an inorganic acid, and it is preferable to distill and reuse the solvent used for removing the photosensitive layer.
No. 8 publication. In the method of regenerating a substrate of a cylindrical electrophotographic function-separated type organic photoreceptor in which the undercoat layer is formed of a thermosetting resin, a cleaning brush and a solvent capable of dissolving the charge transport layer on the undercoat layer are used. It has 17-43 three-dimensional skeleton structure per 25 mm cell range, JIS K
In the physical property test of the soft urethane foam for cushion according to -6401, the hardness is 7 to 17.0 kgf and the tensile strength is 1.0.
~ 1.5 kg / cm ² , using a polyurethane foam having an elongation rate of 200% or more, the cylindrical aluminum substrate having the undercoat layer after rotational contact removal cleaning is brought into rotational contact with an elastic polishing wheel. A method for regenerating a substrate is characterized in that the outer surface of a cylindrical aluminum substrate is roughened at the same time as polishing and removing the undercoat layer.
It is described in Japanese Patent Publication No. 295908.

In recent years, electrophotographic photoconductors have been widely used in facsimiles, printers, etc. in addition to copying machines. The form thereof may be a sheet form, a belt form, a drum form, etc., but a drum form is common, and in the case of a drum form electrophotographic photosensitive member, a substrate made of aluminum or aluminum alloy is often used.

In recent years, the demand for reusing resources has been increasing, and various methods for reusing resources have also been investigated for electrophotographic photoreceptors from the standpoint of reusing resources. There are several methods for resource reuse. For example, there is a method in which the photosensitive layer is peeled off from the electrophotographic photosensitive member that has been used and the substrate is used as an aluminum material. However, with this method, although the substrate can be used as an aluminum material, it is not efficient because the substrate processed into a cylindrical shape cannot be utilized effectively.

Therefore, there is a method of reusing the substrate, in which the photosensitive layer is peeled off from the used photosensitive member, and then the photosensitive layer is formed again and used again as an electrophotographic photosensitive member. This method is efficient because the substrate formed in a cylindrical shape can be reused, but when the photosensitive layer has a layer that is difficult to peel off, the photosensitive layer cannot be completely peeled off, which is not sufficient. For example, when any one of the photosensitive layers is a curable layer, it was not possible to sufficiently peel off the layer only by using an organic solvent. Particularly when the cured layer contains an inorganic filler, it was extremely difficult to peel the cured layer without damaging the substrate. The conventional peeling method is introduced along with its problems.

In Japanese Patent Laid-Open No. 2000-10302, the coating film is peeled off by a centerless polishing machine, but this method involves not only the coating film but also the surface of the substrate, and the outer diameter of the substrate becomes small. There is. Japanese Patent Laid-Open No. 2000-275
Japanese Patent No. 867 proposes a method of making a notch in a coating film and peeling it so as to peel it off. However, this method has a problem that the peeled film is cut in the middle or cannot be peeled off sufficiently. In Japanese Patent Application Laid-Open No. 10-177254, the substrate is heat-treated at high temperature by using stainless steel instead of aluminum. However, when the photosensitive layer contains an inorganic substance such as titanium oxide, it is likely to be burnt and difficult to remove evenly. Is.

[0007]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a substrate without damaging or damaging the substrate even when at least one of the layers of the photoreceptor is a photoreceptor containing a curable layer.
It is to provide a method for peeling a photosensitive layer.

[0008]

Means for Solving the Problems The above-mentioned problems are solved by (1) erasing an electrophotographic photoreceptor having an inorganic filler-containing layer of the present invention while irradiating it with an ultrasonic wave while peeling the photosensitive layer. A photosensitive layer peeling device using an ultrasonic tank used at the time, the surface including a surface for performing ultrasonic oscillation is on the bottom surface,
Further, it is characterized in that a groove having a width of 5 mm or more and a depth of 5 mm or more is provided around the surface for performing ultrasonic oscillation, or the surface including the surface for performing ultrasonic oscillation is projected by 1 cm or more from the periphery. Electrophotographic photoconductor photosensitive layer peeling device ",
(2) "The length of any one of the surfaces of the bottom surface of the ultrasonic tank, including the surface for performing ultrasonic oscillation, is equal to or wider than the width of the photosensitive layer of the photoreceptor on which the photosensitive layer is to be peeled off. And a photosensitive layer peeling device for an electrophotographic photosensitive member according to item (1).

Further, the above-mentioned problem is (3) of the present invention, in which an electrophotographic photosensitive member having at least one layer insoluble in an organic solvent is irradiated with ultrasonic waves while being immersed in the organic solvent to peel off the photosensitive layer. The ultrasonic transducer is capable of sweeping a part or the whole of an oscillation frequency range of 20 KHz to 535 KHz, and sweeps a width of 2.5 KHz or more at a sweep speed of 0.1 KHz / sec or more. And (4) "an electrophotographic photosensitive member having at least one layer insoluble in an organic solvent is immersed in an organic solvent, and a plurality of frequencies are superposed on the electrophotographic photosensitive member. A method of peeling a photosensitive layer by irradiating ultrasonic waves, wherein at least one of constituent frequencies of superposed ultrasonic waves is 20 KHz to 40
Method for peeling photosensitive layer characterized by being in the range of KHz ", (5)" while dipping an electrophotographic photoreceptor having at least one layer insoluble in an organic solvent in an organic solvent,
On the other hand, it is a method of peeling the photosensitive layer by irradiating ultrasonic waves, and the frequency of the irradiating ultrasonic waves is 20 KHz to 535K.
The method of peeling a photosensitive layer characterized by sequentially irradiating two or more different frequencies within Hz, (6) "The organic solvent used is a solvent containing at least a pyrrolidone compound. (3) The method for peeling a photosensitive layer according to any one of (5) to (7), "The organic solvent used is N-methyl-2-pyrrolidone. ) Item, the photosensitive layer peeling method ",
(8) “The temperature of N-methyl-2-pyrrolidone is 40 to 9
It is 0 degreeC, The water content rate contained in the photosensitive layer peeling method as described in said (7) term | item "(9)" N-methyl-2-pyrrolidone is 5 weight% or less. (10) The method for peeling a photosensitive layer according to the item (8), wherein the electrophotographic photosensitive member is immersed in a bath containing a solvent, and ultrasonic irradiation is performed after 5 seconds or more and 10 minutes or less. Peeling is then performed to remove the photosensitive layer according to any one of the above items (3) to (9) ", (1
1) "The method for peeling a photosensitive layer according to any one of the items (3) to (9), wherein the undercoat layer of the electrophotographic photosensitive member is formed of a pigment and a curable resin. , (1
2) "The method for peeling a photosensitive layer according to any one of the above items (3) to (9), characterized in that the thickness of the substrate is 0.6 mm or more"; Surface roughness is JIS
Rz defined by B0601 is 1.9 μm or less, and the photosensitive layer peeling method according to any one of the above items (3) to (9) ”is achieved.

Further, the above-mentioned problem is (13) of the present invention, wherein the substrate for an electrophotographic photosensitive member is one in which the photosensitive layer is peeled off by the method described in any one of (3) to (13) above. Is achieved.

The above object can be achieved by (15) of the present invention, "an electrophotographic photosensitive member characterized by being produced by using the electrophotographic photosensitive member substrate according to the above (14)." It

Further, the above object can be achieved by (16) of the present invention, "an electrophotographic process cartridge characterized by using the electrophotographic photosensitive member according to the above (15)".

Furthermore, the above-mentioned problem is (1) of the present invention.
7) The present invention is achieved by "an electrophotographic apparatus characterized by using the electrophotographic photosensitive member according to item (15) or the process cartridge for electrophotography according to item (16)".

Preparation of Photoreceptor First, a method for producing an electrophotographic body used for peeling evaluation in Examples and Comparative Examples of the present invention will be described. (1) Fabrication of substrate Outer diameter 30.5 mm, inner diameter 28.5 mm, length 350 m
The aluminum cylindrical body of m 2 was attached to a lathe and cut, and the thickness was 0.75 mm and the surface roughness Rz was 1.5 μ.
m of the electrophotographic photoreceptor substrate was obtained. This aluminum substrate was dipped in a cleaning tank containing a surfactant, irradiated with ultrasonic waves for cleaning, and then rinsed thoroughly with pure water. (2) Formation of undercoat layer Next, a resin coating having the following composition is applied to the surface of the drum type substrate by a dipping method, and then heated at 150 ° C. for 15 minutes to be heat-cured to a thickness of about 5 μm on the surface of the substrate. Undercoat layer was formed. Titanium oxide 20 parts by weight Alkyd resin 10 parts by weight Melamine resin 10 parts by weight Methyl ethyl ketone 60 parts by weight (3) Formation of charge generation layer Next, the following composition is formed to form a charge generation layer on the undercoat layer. A resin coating material (coating resin solution) was prepared, and this resin coating material was applied to the above-mentioned substrate by the same dipping method and dried at 100 ° C. for 10 minutes to form a charge generation layer on the undercoat layer. Butyral resin (UCK XYHK) 1 part by weight Disazo pigment [the following formula (1)] 9 parts by weight

[0015]

[Chemical 1] Cyclohexanone 30 parts by weight Tetrahydrofuran (THF) 30 parts by weight (4) Formation of charge transport layer Further, a resin coating material (coating resin liquid) having the following composition is formed in order to laminate the charge transport layer on the charge generation layer. This resin coating was prepared and applied to the above-mentioned substrate by the same dipping method, and then dried at 120 ° C. for 15 minutes to form a charge transport layer on the charge generation layer. Polycarbonate resin 10 parts by weight Charge transfer agent [formula (2) below] 10 parts by weight Dichloromethane 80 parts by weight The polycarbonate resin is Teijin Panlite K
-1300 was used.

[0016]

[Chemical 2]

[0017]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples (Examples of Claims 1 and 2 and Comparative Example). FIG. 1 is a schematic cross-sectional view of a photosensitive layer peeling apparatus suitable for carrying out Claims 1 and 2. Show. In FIG. 1, (1) is an ultrasonic tank, (2) is an ultrasonic oscillator, (3) is a surface including an ultrasonic oscillation surface, and (4)
Is a groove around the ultrasonic wave oscillating surface, (5) is an ultrasonic wave oscillating power source, (6) is an electrophotographic photosensitive member for peeling, and (7) is a holding jig for the electrophotographic photosensitive member. In Claim 2, the length of any one side of the bottom surface of the ultrasonic tank for performing ultrasonic oscillation is 80% of the length of the photosensitive body on which the photosensitive layer is to be peeled off.
It is characterized by the above. Here, a plurality of ultrasonic oscillators may be attached to the stripping tank, and the number and arrangement of ultrasonic oscillators may be any as long as ultrasonic waves can be uniformly applied. FIG. 2 shows an example in which two ultrasonic oscillators are attached.

FIG. 3 is a schematic cross-sectional view of a peeling tank used in a comparative example. (1) is an ultrasonic tank, (2) is an ultrasonic oscillator,
(3) is a surface including an ultrasonic wave oscillating surface, (5) is an ultrasonic wave oscillating power supply section, (6) is an electrophotographic photoreceptor for peeling,
(7) shows a holding jig for the electrophotographic photosensitive member. 1, 2 and 3 are merely views showing the structure of the peeling tank, and the dimensions of the photoconductor and the ultrasonic peeling tank, and the scale of the ultrasonic oscillator and the like are not accurately represented.

Table 1 shows the peeling conditions and peeling results of the photosensitive layers of Examples 1 and 2 and Comparative Examples 1 and 2. The peeling result was evaluated visually and using a 10 times magnifier. The conditions common to Examples 1 and 2 and Comparative Examples 1 and 2 are shown in Table 2.

[0020]

[Table 1]

[0021]

[Table 2]

From Table 1, in Example 1 satisfying claim 1, the first and 50th photosensitive layers could be completely peeled off, but in Comparative Example 1 having no groove at the bottom, the first one was completely peeled off. In the 50th line, there was uneven peeling in part. In this photoconductor, the photosensitive layer contains an inorganic filler, and this is dispersed and settled in the stripping liquid upon stripping. With the structure of the stripping tank shown in claim 1, the inorganic filler in the stripping liquid oscillates ultrasonically. Even if the number of strips gathered in the grooves around the surface and the number of strips increased, they were not deposited in the stripping solution or on the ultrasonic oscillation surface, and efficient ultrasonic irradiation could be performed. However, in Comparative Example 1, there is no groove around the surface that oscillates ultrasonic waves, and the inorganic filler in the stripping solution is dispersed in the stripping solution or is deposited on the ultrasonic wave oscillating surface during stripping, which hinders ultrasonic wave propagation and causes stripping unevenness. It is thought that it became. In addition, in Example 2 which satisfies claim 2, complete peeling could be performed, but in the comparative example in which the width of the surface that oscillates ultrasonic waves is narrower than the width of the photosensitive layer, there are portions where peeling is insufficient at both ends. The effect of item 2 was confirmed.

Supplementary explanation of claim 1: In claim 1,
The groove around the surface that oscillates ultrasonic waves has a width of 5 mm or more,
A groove having a depth of 5 mm or more is preferable, but a width of 1 cm or more and a depth of 1 cm or more are preferable. The width may be 5 cm or less, and the depth may be 5 cm or less. The groove portion becomes a shadow during ultrasonic wave propagation, the ultrasonic wave is not sufficiently transmitted to the stripping solution located here, and the inorganic filler in the stripping solution is likely to settle, which is effective. Further, the stripping tank may be provided with an inlet and an outlet for the stripping solution to circulate the stripping solution.

Supplementary description of claim 2: In claim 2, the length of any one side of the surface of the bottom surface of the ultrasonic tank, including the surface for performing ultrasonic oscillation, is the photosensitivity of the photoconductor for which the photosensitive layer is to be peeled off. Characterized to be equal to or wider than the width of the layers. Here, it is important that the photosensitive layer is arranged so as to be completely opposed to the ultrasonic wave oscillating surface, and the photosensitive layer surface should not extend beyond the ultrasonic wave oscillating surface.

(Examples of claims 3 to 11 and comparative example) Table 3
The photosensitive layer was peeled off under the conditions shown in. The results of observation of the peeled state are also shown in Table 3. The conditions common to the examples and comparative examples in Table 3 are shown in Table 4.

[0026]

[Table 3]

[0027]

[Table 4]

In claims 3, 4 and 5, the ultrasonic irradiation is swept,
Superimposition and switching are shown, but peeling unevenness occurs in Comparative Examples 1 and 2 which do not adopt these methods.
The effect of was confirmed.

Further, in the present invention, the temperature of the stripping solution is 40 to
Although the temperature is 90 ° C., peeling occurs in Comparative Example 3 at 30 ° C., which is lower than this temperature, and the effect of claim 8 can be confirmed.

According to a tenth aspect of the present invention, the electrophotographic photosensitive member according to any one of the third to ninth aspects is immersed in a bath containing a solvent for 5 seconds or longer, and 1
Ultrasonic irradiation is performed after 0 minutes or less for peeling, but there is peeling unevenness in Comparative Example 4 in which the immersion time is 3 seconds, and peeling unevenness is also observed in Comparative Example 5 where the immersion time is 13 minutes. Was recognized. From this, the effect of claim 10 was confirmed.

Supplementary description of claim 3: In claim 3, the ultrasonic transducer is capable of sweeping a part or all of the oscillation frequency range of 20 KHz to 535 KHz, and 0.1 KH.
It is characterized by sweeping a width of 2.5 KHz or more at a sweep speed of z / sec or more, but the output reaction of ultrasonic waves under the assumption of sweep is preferably ± 30% or less, and more preferably 50% or less. . Further, in claim 3, it is preferable to use the device shown in claim 1 or claim 2, but it is not always essential, and a peeling device other than those described in claim 1 or 2 can also be used. is there.

Supplementary explanation of claim 4: In claim 4, a method of irradiating an ultrasonic wave in which a plurality of frequencies are superposed to peel off the photosensitive layer, wherein at least one of the constituent frequencies of the superposed ultrasonic waves is 20 KHz to It is characterized by being in the range of 40 KHz, but the constituent ultrasonic waves of the superposed ultrasonic waves are
If the maximum strength is 100, the others are preferably 50 or more. Further, in claim 4, it is preferable to use the device shown in claim 1 or claim 2, but it is not necessarily essential, and the device according to claim 1 or claim 2 is used.
A peeling device other than the one shown in can also be used.

Supplementary explanation of claim 5: According to claim 5, the frequency of the ultrasonic waves to be applied is two or more different frequencies within the range of 20 KHz to 535 KHz, and the ultrasonic waves to be applied are different. It is preferable that the second strength is 50 or more when the strength of the maximum strength is 100. Further, in claim 5, it is preferable to use the device described in claim 1 or 2,
It is not always essential, and a peeling device other than the one described in claim 1 or 2 can be used.

Supplementary explanation of claims 6 and 7: The stripping solution used in the present invention is characterized by containing at least a pyrrolidone compound. Examples of the pyrrolidone compound include 2-pyrrolidone, 3-pyrrolidone, N-alkyl-2-pyrrolidone (for example, N-methyl-pyrrolidone, N-ethyl-2
Pyrrolidone, N-propyl-2-pyrrolidone), 5-alkyl-2-pyrrolidone (eg 5-methyl-2-pyrrolidone), N-vinyl-2-pyrrolidone, N-alkyl-3-pyrrolidone (eg N-methyl) -3-pyrrolidone, N-ethyl-3-pyrrolidone, N-propyl-3pyrrolidone) and the like are possible. N-methyl-2-pyrrolidone is particularly effective. The pyrrolidones may be used alone or as a mixture of two or more kinds.

Further, the addition of an antioxidant to the stripping solution of the present invention suppresses the generation of peroxide, which is preferable when the charge transport agent is recovered from the stripping solution and used. The antioxidant is 0.01 to 5.0% by weight, preferably 0.05 in the stripping solution.
˜2.0%, more preferably 0.05 to 1.5%. Examples of the antioxidant include a phenol antioxidant, a phosphite-based antioxidant, and a sulfur-based antioxidant as exemplified below.

The phenolic antioxidant is 2,6
-Di-tert-butyl-4-methylphenol, 2,
5-di-tert-butylhydroquinone, 2,6-di-
monophenolic compounds such as tert-butyl-α-dimethylamino-P-cresol, 4,4′-bis (2,2
6-di-tert-butylphenol), 2,2'-methylene-bis (4-methyl-6-tert-butylphenol), 4,4'-methylene-bis (2,6-di-te).
rt-butylphenol), 4,4′-butylidene-bis (3-methyl-6-tert-butylphenol), and other bisphenol compounds, 4,4′-thiobis (3-
Methyl-6-tert-butylphenol), 2,2 '
-Thiobis (6-tert-butyl-o-cresol), 2,2'-thiobis (4-methyl-6-tert)
-Butylphenol) and other thiobisphenol compounds, tetrakis [methylene-3- (3,5-di-ter]
t-butyl-4-hydroxyphenyl) propionate] methane, tris (2-methyl-4-hydroxy-5)
Examples include trisphenol-based compounds such as -tert-butyl-phenol) butane.

Examples of the phosphite antioxidant include triphenyl phosphite, trisnonylphenyl phosphite, trioctyl phosphite, tris (mono- and di-nonylphenyl) phosphite.

Examples of sulfur antioxidants include dilauryl thiodipropionate and distearyl thiodipropionate.

Supplementary explanation of claim 8: In claim 7,
The temperature of N-methyl-2pyrrolidone is 40 to 90 ° C, and the temperature is preferably 70 to 90 ° C.

Supplementary explanation of claim 9: The content of water in N-methyl-2pyrrolidone is characterized by being 5% by weight or less, but the content of water is preferably 3% or less. , And more preferably 1% or less.

Supplementary explanation of claim 10: In claim 10,
Immerse the electrophotographic photoreceptor in a bath containing solvent for 5 seconds or more,
It is characterized in that the ultrasonic irradiation is performed after 10 minutes or less to perform the peeling, but the ultrasonic irradiation may be performed in the immersed tank as it is, or the ultrasonic irradiation may be taken out from the immersed tank and be performed in another ultrasonic peeling tank. You can do it in. Here, the immersion time is 5 seconds or more and 10 minutes or less, preferably 30 seconds or more and 3 minutes or less.

(Examples and Comparative Examples of Claims 12 and 13) An aluminum cylinder having an outer diameter of 30.5 mm, an inner diameter of 28.5 mm, and a length of 350 mm was attached to a lathe, and the aluminum was shown in Table 5 after cutting. A substrate was prepared.

[0043]

[Table 5]

A photosensitive layer was formed on the electrophotographic photosensitive member substrate shown in Table 5 by the method described above to obtain an electrophotographic photosensitive member substrate.

The prepared electrophotographic photosensitive member was peeled off under the same conditions as those for peeling off the photosensitive layer shown in Example 10.
Visually observe the peeling state of the photosensitive layer and with a magnifier of 10 times,
The surface condition of the substrate was visually observed with a 100 × optical microscope. The observation results are shown in Table 6.

[0046]

[Table 6]

An embodiment 12 satisfying claims 12 and 13,
No abnormalities were found in the bases of Nos. 13 and 14,
In Comparative Example 10 in which the thickness of the base was 0.6 mm, although the peeling was good, the deformation of the base was confirmed. Further, in Comparative Example 11 in which Rz was 2, the deformation of the cutting peak was recognized.

Supplementary explanation of claim 12: In the present invention,
The substrate is characterized by having a thickness of 0.6 mm or more, more preferably 0.8 mm or more. When the thickness of the substrate is 0.6 mm or less, it is likely to be damaged by the irradiation of ultrasonic waves, and the surface property of the substrate may change.

Supplementary explanation of claim 13: In the present invention,
The surface roughness of the substrate is characterized by Rz being 1.9 μm or less, more preferably 1.3 μm or less. If the surface roughness is 1.9 μm or more, it is likely to be damaged by ultrasonic irradiation, and the surface properties of the substrate may change.

(Examples of Claims 14, 15, 16 and 17) Example 11 (Examples of Claim 14) Twenty electrophotographic photoconductors were produced by the method described in the method for producing photoconductors above. The photosensitive layer was peeled off by the method shown in Example 1. The substrate thus obtained is referred to as Example 11.
All the 20 substrates of Example 11 were good without any scratches or peeling unevenness.

Example 12 (Example of Claim 15) 20 electrophotographic photoconductor substrates prepared in Example 11 were washed with pure water, and an undercoat layer, a charge generation layer, and A charge transport layer was formed. The electrophotographic photosensitive member thus produced is referred to as Example 12. The electrophotographic photosensitive member shown in Example 12 was compared with the photosensitive member before the peeling treatment, but there were no coating defects and the electrical characteristics were the same.

Embodiment 13 (Embodiment of Claim 16) FIG. 4 shows an electrophotographic process cartridge suitable for carrying out the present invention. In FIG. 4, (11) is an electrophotographic photosensitive member, (12) is a shaft for rotating the electrophotographic photosensitive member,
(13) is charging means, (14) is image exposure light, (15)
Is a developing means, (16) is a transfer means, (17) is a transfer material such as paper, (18) is an image fixing means, (19) is a cleaning means, and (20) is pre-exposure light for static elimination, (21)
Indicates a process cartridge container. FIG. 4 shows an example of the structure, and each means may be a method other than that shown in FIG. For example, as the charging means (13), a known charging means such as a corotron, a scorotron, or a charging roll can be used. The light sources of the image exposure light (14) and the pre-exposure light (20) are fluorescent lamps, tungsten lamps, halogen lamps,
Mercury lamp, sodium lamp, light emitting diode (LED), semiconductor laser (LD), electroluminescence (E
Light emitting means such as L) can be used. Further, various filters such as a sharp cut filter, a bandpass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a predetermined wavelength range. The cleaning means (19) may be a cleaning blade alone, or may be used in combination with a cleaning brush or a blade. In the process cartridge shown in FIG. 4, the cleaning means may not be included in the process cartridge. Further, a light emitting means or a transfer means which are not incorporated in FIG. 4 may be incorporated in the process cartridge.

The electrophotographic photosensitive member shown in Example 12 was mounted on this process cartridge and inspected according to a usual inspection method, and the electrical characteristics, rotational load, and image quality were all good.

Embodiment 14 (Embodiment of Claim 17) FIG. 5 is a structural view of an electrophotographic apparatus suitable for carrying out the invention. In FIG.
(31) is an electrophotographic photosensitive member, (32) is a shaft for rotating the electrophotographic photosensitive member, (33) is a charging unit, (34) is image exposure light, (35) is a developing unit, and (36) is a transfer unit. ,
(37) is a rolled material such as paper, (38) is an image fixing means, (3)
9) is a cleaning means, and (40) is pre-exposure light for removing charge. FIG. 5 shows an example of the structure, and each means may be a method other than that shown in FIG. For example, as the charging means (33), a known charging means such as a corotron, a scorotron, or a charging roll can be used. Image exposure light (3
4) and the light source of the pre-exposure light (40) are fluorescent lamp, tungsten lamp, halogen lamp, mercury lamp, sodium lamp, light emitting diode (LED), semiconductor laser (L).
D), electroluminescence (EL) and other light emitting means can be used. Further, various filters such as a sharp cut filter, a bandpass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a predetermined wavelength range. The cleaning means (39) may be a cleaning blade alone, or may be used in combination with a cleaning brush or a blade.

The electrophotographic photosensitive member shown in Example 12 was attached to Ricoh's Imagio MF650 having the structure shown in FIG. This is Example 14. Then, after continuously printing 20 sheets of A4 size character image, the stop was repeated for 10 minutes, and 20 sheets of images were evaluated every 1000 sheets. However, problems such as point defects, unevenness and stains were not recognized in the images. It was confirmed that there was no problem with the photographic equipment.

Supplementary explanation of claims 1 to 13: In the present invention, various types of ultrasonic vibrators can be used. For example, lead zircon titanate vibrator (PZT), bolted Langevin vibrator (BLT), etc. Can be used. The amount of electric power applied to the ultrasonic transducer depends on the type of the transducer, 6 W / cm ² or more for PZT and ² for BLT.
It is generally 0 W / cm ² or more.

In the present invention, the stripping tank may be provided with a stripping solution circulating system or a sending system to circulate or send the stripping solution, or a filter may be incorporated in the circulating sending system. When incorporating a filtration device, it is effective to select a filtration filter according to the size of the inorganic filler contained in the photosensitive layer. When the stripping solution is circulated or sent, it may be performed when the ultrasonic irradiation is stopped or may be performed when the ultrasonic irradiation is performed. When the stripping solution is circulated or sent at the time of ultrasonic wave irradiation, it is important to pay attention so that uneven ultrasonic wave irradiation does not occur. When circulating or sending the stripping solution, the solution outlet of the stripping tank is preferably located near the bottom surface of the stripping tank, and the solid content in the stripping solution is efficiently discharged by providing the solution outlet near the bottom surface. Will be possible.

[0058]

As is clear from the detailed and specific description above, in the photosensitive layer peeling device for an electrophotographic photosensitive member according to claim 1 of the present invention, the surface including the surface for ultrasonic oscillation is the bottom surface. Yes, and 5 mm wide around the surface that performs ultrasonic oscillation
As described above, since there is a groove having a depth of 5 mm or more, or the surface including the surface for ultrasonic oscillation protrudes by 1 cm or more from the periphery thereof, even if the photosensitive layer of the photoreceptor is a photosensitive layer containing an inorganic filler. In addition, the inorganic filler does not stay in the stripping solution or accumulate on the ultrasonic wave oscillating surface, so that stable stripping is possible even if the number of stripping treatments increases. Further, in the photosensitive layer peeling apparatus for an electrophotographic photosensitive member according to claim 2 of the present invention, the length of any one side of the surface of the bottom surface of the ultrasonic bath including the surface for ultrasonic oscillation is used for peeling the photosensitive layer. Since the width is equal to or wider than the width of the photosensitive layer of the intended photoreceptor, the entire surface of the photosensitive layer can be uniformly stripped. Further, in the photosensitive layer peeling method according to claim 3 of the present invention, ultrasonic waves are oscillated at an oscillation frequency of 20 KHz to 53 while the electrophotographic photosensitive member is immersed in an organic solvent.
Since a part or the whole of the range of 5 KHz is irradiated, even if the electrophotographic photosensitive member to be peeled has at least one layer insoluble in an organic solvent, it can be sufficiently peeled. Further, the photosensitive layer peeling method according to claim 4 of the present invention, while dipping the electrophotographic photosensitive member in an organic solvent, at least one ultrasonic wave superposed a plurality of frequencies in the range of 20KHz ~ 40KHz. Since irradiation is performed, even if the electrophotographic photosensitive member to be peeled is an electrophotographic photosensitive member having at least one layer insoluble in an organic solvent, it can be sufficiently peeled. Further, in the photosensitive layer peeling method according to claim 5 of the present invention, the frequency is 20 KHz to 535 K.
Since two or more different frequencies within Hz are sequentially irradiated, even if the electrophotographic photosensitive member to be peeled is an electrophotographic photosensitive member having at least one layer insoluble in an organic solvent, it can be sufficiently peeled. Become. Moreover, the photosensitive layer peeling method according to claim 6 of the present invention uses the peeling method according to claims 3 to 5, and since the organic solvent used is a solvent containing at least a pyrrolidone compound, Even if the electrophotographic photosensitive member is an electrophotographic photosensitive member having at least one layer insoluble in an organic solvent, it can be sufficiently peeled off. Further, the photosensitive layer peeling method according to claim 7 of the present invention uses the peeling method according to claims 3 to 5, and since the organic solvent used is N-methyl-2pyrrolidone, Even if the electrophotographic photosensitive member is an electrophotographic photosensitive member having at least one layer insoluble in an organic solvent, it can be sufficiently peeled off. Further, the photosensitive layer peeling method according to claim 8 of the present invention uses N-methyl-2 as a peeling liquid.
Pyrrolidone is used and the temperature of the stripper is 40 ~ 90 ° C.
Therefore, even if the electrophotographic photoconductor to be peeled is an electrophotographic photoconductor having at least one layer insoluble in an organic solvent, it can be sufficiently peeled. The method for stripping a photosensitive layer according to claim 9 of the present invention uses N-methyl-2pyrrolidone as a stripping solution, and the water content of N-methyl-2pyrrolidone is 5% by weight or less. Therefore, even if the electrophotographic photoconductor to be peeled is an electrophotographic photoconductor having at least one layer insoluble in an organic solvent, it can be sufficiently peeled. Further, claim 10 of the present invention
In the method for peeling the photosensitive layer shown in (1), the electrophotographic photosensitive member is immersed in a tank containing a solvent, and after 5 seconds or more and 10 minutes or less, ultrasonic irradiation is performed to perform the peeling, so that the immersion time is 5 seconds or less. Even if the electrophotographic photosensitive member to be peeled is an electrophotographic photosensitive member having at least one layer insoluble in an organic solvent, there is no lack of immersion and no excessive immersion for 10 minutes or more. Can be peeled off. Moreover, since the photosensitive layer peeling method according to claim 11 of the present invention uses the peeling method according to claims 3 to 9, the undercoat layer of the electrophotographic photoreceptor to be peeled is composed of a pigment and a curable resin. Even if formed, it can be peeled off sufficiently. Further, since the photosensitive layer peeling method according to claim 12 of the present invention uses the peeling method according to claims 3 to 9, the substrate is damaged when the thickness is 0.6 mm or more. Peeling is possible without giving.
Moreover, since the photosensitive layer peeling method according to claim 13 of the present invention uses the peeling method according to claims 3 to 9, the surface roughness of the substrate is 1.9 μm in Rz defined in JIS B0601. In the following cases, peeling is possible without damaging the substrate. In the electrophotographic photoreceptor substrate according to claim 14 of the present invention, the photosensitive layer is peeled by the method according to claims 3 to 13, so that the substrate is not damaged and the photosensitive layer is sufficiently peeled. It has been carried out and is a substrate for an electrophotographic photoreceptor having excellent quality. Further, claim 1 of the present invention
Since the electrophotographic photosensitive member shown in 5 uses the electrophotographic photosensitive member substrate according to claim 14, the resource is reused and the electrophotographic photosensitive member is excellent in quality.
Further, since the electrophotographic process cartridge according to claim 16 of the present invention uses the electrophotographic photosensitive member according to claim 15, the resources are reused and the quality is high. It is a process cartridge for photography.
Further, since the electrophotographic apparatus according to claim 17 of the present invention uses the electrophotographic photosensitive member according to claim 15 or the electrophotographic process cartridge according to claim 16, the resources are reused. It is an electrophotographic device that is well-known and has excellent quality.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a photosensitive layer peeling device of the present invention.

FIG. 2 is another schematic cross-sectional view of the photosensitive layer peeling device of the present invention.

FIG. 3 is another schematic cross-sectional view of the photosensitive layer peeling device of the present invention.

FIG. 4 is a diagram showing a process cartridge for electrophotography according to the present invention.

FIG. 5 is a structural diagram of an electrophotographic apparatus according to the present invention.

[Explanation of symbols]

1 ultrasonic bath 2 Ultrasonic oscillator 3 Surfaces including surfaces that generate ultrasonic waves 4 Grooves around the ultrasonic oscillation surface 5 Ultrasonic power supply 6 Electrophotographic photoreceptor for peeling 7 Holding jig 11 Electrophotographic photoreceptor 12 Shaft for rotating electrophotographic photoreceptor 13 charging means 14 Image exposure light 15 Developing means 16 Transfer means 17 Rolled material 18 Image fixing means 19 Cleaning means 20 Pre-exposure light for static elimination 21 Process Cartridge Container 31 Electrophotographic photoreceptor 32 Shaft for rotating electrophotographic photoreceptor 33 charging means 34 Image exposure light 35 developing means 36 transfer means 37 Rolled material 38 image fixing means 39 Cleaning means 40 Pre-exposure for static elimination

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 5/14 G03G 5/14 101E (72) Inventor Naoyuki Kusano 1-3-3 Nakamagome, Ota-ku, Tokyo No. 6 in Ricoh Co., Ltd. (72) Inventor Junichi Yamazaki 1-3-3 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. (reference) 2H068 AA43 AA44 AA59 BA02 BB57 EA14 EA38 EA47 FA27 4D075 BB13Z BB20Z CA22 CA47 CA15 DB07 DC27 EB31

Claims (17)

[Claims] 1. A photosensitive layer peeling apparatus using an ultrasonic bath used when an electrophotographic photosensitive member having a layer containing an inorganic filler is immersed in an organic solvent and irradiated with ultrasonic waves to peel the photosensitive layer. There is a surface including a surface for performing ultrasonic oscillation on the bottom surface, and there is a groove having a width of 5 mm or more and a depth of 5 mm or more around the surface for performing ultrasonic oscillation, or a surface for performing ultrasonic oscillation. A photosensitive layer peeling device for an electrophotographic photosensitive member, characterized in that the surface including is projected by 1 cm or more from the periphery thereof. 2. The length of one side of the surface of the bottom of the ultrasonic tank, including the surface for performing ultrasonic oscillation, is equal to or wider than the width of the photosensitive layer of the photosensitive body on which the photosensitive layer is to be peeled off. The photosensitive layer peeling device for an electrophotographic photosensitive member according to claim 1, wherein. 3. A method of peeling a photosensitive layer by irradiating an electrophotographic photosensitive member having at least one layer insoluble in an organic solvent with an ultrasonic wave while immersing the electrophotographic photosensitive member in the organic solvent. However, it is possible to sweep a part or all of the oscillation frequency range of 20 KHz to 535 KHz, and 0.1 KHz
A method for peeling a photosensitive layer, characterized in that a width of 2.5 KHz or more is swept at a sweeping speed of not less than / sec. 4. An electrophotographic photosensitive member having at least one layer insoluble in an organic solvent is immersed in the organic solvent,
On the other hand, a method of irradiating an ultrasonic wave in which a plurality of frequencies are superposed to peel off the photosensitive layer is characterized in that at least one of constituent frequencies of the superposed ultrasonic waves is within a range of 20 KHz to 40 KHz. Photosensitive layer peeling method. 5. An electrophotographic photosensitive member having at least one layer insoluble in an organic solvent is immersed in the organic solvent,
On the other hand, it is a method of peeling the photosensitive layer by irradiating ultrasonic waves, and the frequency of the irradiating ultrasonic waves is 20 KHz to 535K.
A method for peeling a photosensitive layer, which comprises sequentially irradiating two or more different frequencies within Hz. 6. The method for removing a photosensitive layer according to claim 3, wherein the organic solvent used is a solvent containing at least a pyrrolidone compound. 7. The method for peeling a photosensitive layer according to claim 6, wherein the organic solvent used is N-methyl-2-pyrrolidone. 8. The temperature of N-methyl-2-pyrrolidone is 4
It is 0-90 degreeC, The photosensitive layer peeling method of Claim 7 characterized by the above-mentioned. 9. The photosensitive layer peeling method according to claim 8, wherein the water content ratio contained in N-methyl-2-pyrrolidone is 5% by weight or less. 10. The electrophotographic photosensitive member is dipped in a tank containing a solvent, and after 5 seconds or more and 10 minutes or less, ultrasonic irradiation is performed to perform peeling.
7. The method for peeling a photosensitive layer according to. 11. The method for peeling a photosensitive layer according to claim 3, wherein the undercoat layer of the electrophotographic photosensitive member is formed of a pigment and a curable resin. 12. The method for peeling a photosensitive layer according to claim 3, wherein the substrate has a thickness of 0.6 mm or more. 13. The surface roughness of the substrate is JIS B0601.
The photosensitive layer peeling method according to any one of claims 3 to 9, wherein Rz defined in (1) is 1.9 µm or less. 14. A substrate for an electrophotographic photosensitive member, the photosensitive layer of which has been peeled off by the method according to any one of claims 3 to 13. 15. An electrophotographic photoreceptor prepared by using the electrophotographic photoreceptor substrate according to claim 14. 16. A process cartridge for electrophotography, which uses the electrophotographic photosensitive member according to claim 15. 17. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 15 or the process cartridge for electrophotography according to claim 16.