JPH0784477A - Electrophotoreceptor and electrophotographic device with the same - Google Patents

Abstract

PURPOSE:To provide the photoreceptor and the device with the same capable of obtaining an excellent image, and eliminating the need of consideration for the dimensional accuracy in holding a grounding member contacting with a cylindrical substrate. CONSTITUTION:As for the photoreceptor 25 provided with the conductive layer 23 and the photosensing layer 21 on the nonmetallic cylindrical substrate 24 or the conductive layer 23, the insulated layer 22 and the photosensing layer 21 on the nonmetallic cylindrical substrate 24 in this order, the photoreceptor 25 and the device with the same are grounded through the same face as the coated face of the photosensing layer 21 by the electrical grounding member 26 fitted to the outside of the substrate 24. Thus, the photoreceptor 25 and the device with the same capable of obtaining the excellent image, eliminating the need of consideration for the dimensional accuracy in holding the grounding member 26 contacting with the cylindrical substrate 24, lightening the weight and reducing the costs can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member and an electrophotographic apparatus having the same, and more particularly to an electrophotographic photosensitive member which provides stable image quality for a long period of time.

[0002]

2. Description of the Related Art In recent years, organic photoconductors have become popular as electrophotographic photoconductors. The first reason is that, unlike the inorganic photoconductor, the organic photoconductor exhibits high sensitivity in the wavelength range of the semiconductor laser, and the sensitivity in the general visible region is also good.

The second reason is that the inorganic photosensitive member is provided with a photosensitive layer on the substrate by a method such as vacuum vapor deposition and glow discharge, so that the equipment cost is high and it is severe under high heat or high vacuum. In order to adopt such conditions, it is necessary to use a material having excellent heat resistance and volatility resistance as the substrate, which increases the substrate management cost, but the organic photoreceptor has the same manufacturing conditions as the inorganic photoreceptor. Since it is not strict, it is possible to reduce the manufacturing cost.

By the way, a metal such as aluminum, steel, copper or nickel, or a non-metal such as paper or plastic is used as the substrate of the inorganic or organic photoreceptor, but the cylindrical substrate is easily grounded. In the present situation, aluminum is used as the substrate in terms of dimensional stability.

However, aluminum has a drawback in that it has high physical distribution costs, cutting and surface polishing costs, and poor workability. In order to improve this point, price reduction, weight reduction,
It has been proposed to use a resin molded from a resin such as plastic with excellent processability in a cylindrical shape as the base of the photoconductor, but if it is repeatedly used, the background stain becomes conspicuous,
Further, there is a problem that the obtained copy quality becomes unclear.

Therefore, by imparting conductivity to the resin substrate and its surface layer as disclosed in JP-A-1-102577 and JP-A-62-279344, there is no abnormal image or background stain even after repeated use. It is said that it can provide a clear copy image. However, since a resin base is used as the base, electrical grounding cannot be achieved unless a conductive flange is directly attached to the conductive layer on the surface of the base as in Japanese Utility Model Laid-Open No. 63-20176. The dimensional accuracy of the flange is strict to obtain the layer and electrical grounding,
In addition, there is a problem that the conductive layer peels off when the flange is pressed.

It is an object of the present invention to provide an electrophotographic photosensitive member having strict dimensional accuracy, facilitating electrical grounding without peeling of a conductive layer, and having no abnormal image or background stain even after repeated use, and the same. An object is to provide an electrophotographic apparatus.

[0008]

That is, the present invention relates to an electrophotographic photosensitive member having a conductive layer and a photosensitive layer in this order on a non-metallic cylindrical substrate, by an electrical grounding member attached to the outside of the substrate. An electrophotographic photosensitive member characterized by being grounded from the same surface as the coated surface of the photosensitive layer.

Further, the present invention provides an electrophotographic photosensitive member having a conductive layer, an insulating layer and a photosensitive layer in this order on a non-metallic cylindrical substrate, by the electrical grounding member attached to the outside of the substrate. The electrophotographic photoreceptor is characterized in that it is grounded from the same surface as the coated surface of the layer.

The present invention is also an electrophotographic apparatus having these electrophotographic photosensitive members.

The present invention is used in a grounding method in which an electrical grounding member is attached to the outside of the base and is not fixed to the openings at both ends of the base.

The details of the present invention will be described below.

As the material of the non-metallic cylindrical substrate forming the main part of the photosensitive drum, plastic or a mixture containing plastic as a main component is selected. The plastic resin used includes, but is not limited to, ABS resin, urethane resin, phenol resin, polyimide resin and polyester resin, and is selected from a wide range of resins. As an example of the use of plastics used now,
An example is a resol-type phenol resin.

In the present invention, a reinforcing agent such as glass fiber may be added to enhance the strength of the phenol resin cylindrical substrate. In addition, a conductive material or the like may be added for the purpose of removing a trouble due to static electricity of the resin substrate. Further, if necessary, a filler or the like may be added to improve the softening point, provide dimensional stability, and impart conductivity.

Next, if a photosensitive layer is provided directly on the substrate, charging will not occur and the sensitivity will decrease. Therefore, for example, an aluminum vapor deposition layer must be provided as a conductive layer.

The photosensitive layer in the present invention may be either a laminated photoreceptor having a charge generation layer and a charge transport layer, a single layer photoreceptor or a photoreceptor provided with a surface protective layer.

The charge generating layer is formed of a charge generating substance and a resin binder.

As the resin binder, polystyrene,
Styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer,
Polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyvinylidene chloride, polyacrylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly- Examples thereof include thermoplastic or thermosetting resins such as N-vinylcarbazole, acrylic resin, silicon resin, epoxy resin, melamine resin, urethane resin, phenol resin, and alkyd resin.

As the charge generating substance, for example, CI Pigment Blue 25 [Color Index (CI) 2
1180], CI Pigment Red 41 (CI 2
1200), CI Acid Red 52 (CI 45
100), CI Basic Red 3 (CI 452
10), and further, a phthalocyanine-based pigment having a porphyrin skeleton, an azurenium salt pigment, a squalic salt pigment, and an azo pigment having a carbazole skeleton (JP-A-53-53).
95033), azo pigments having a stilstilbene skeleton (described in JP-A-53-138229), azo pigments having a triphenylamine skeleton (described in JP-A-53-132547), and dibenzothiophene. Azo pigments having a skeleton (described in JP-A-54-21728), azo pigments having an oxadiazole skeleton (described in JP-A-54-12742), azo pigments having a fluorenone skeleton (JP-A-54). No. 22834), an azo pigment having a bisstilbene skeleton (described in JP-A-54-17733), and an azo pigment having a distyryloxadiazole skeleton (JP-A-54-21).
29), azo pigments having a distyrylcarbazole skeleton (described in JP-A-54-17734), and triazo pigments having a carbazole skeleton (JP-A-57-195767 and 57-195768). , Etc., and also CI Pigment Blue 1
6 (CI 74100) and other phthalocyanine pigments,
Indigo pigments such as SI BAT Brown 5 (CI 73410) and SI BAT Die (CI 73030), organic pigments such as perylene pigments such as Argos Scarlet B (manufactured by Violet) and Industrance Scarlet R (manufactured by Bayer). Can be used.

The thickness of the charge generation layer is suitably about 0.05 to 2 μm, preferably 0.1 to 1 μm.

The charge generating layer can be formed by dissolving or dispersing the binder and the charge generating substance described above in a suitable solvent, and coating and drying this. As a solvent
Benzene, toluene, xylene, methylene chloride, dichloroethane, monochlorobenzene, dichlorobenzene, ethyl acetate, butyl acetate, methyl ethyl ketone, dioxane, tetrahydrofuran, cyclohexanone, methyl cellosolve, ethyl cellosolve and the like can be used alone or in combination.

In the charge transport layer, a charge transport material and a resin binder similar to that used in the charge generation layer are dissolved or dispersed in a suitable solvent, and the solution is coated on the charge generation layer.
It can be formed by drying. If necessary, a plasticizer, a leveling agent, etc. may be added.

As the charge transport material, poly-N-vinylcarbazole and its derivative, poly-γ-carbazolylethylglutamate and its derivative, pyrene-formaldehyde condensate and its derivative, polyvinylpyrene, polyvinylphenanthrene, oxazole derivative, Oxadiazole derivative, imidazole derivative, triphenylamine derivative, 9- (p-diethylaminostyryl) anthracene, 1,1-bis- (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline, phenylhydrazones, Examples thereof include electron-donating substances such as α-phenylstilbene derivatives.

As the solvent at this time, tetrahydrofuran, dioxane, toluene, monochlorobenzene, dichloroethane, methylene chloride or the like can be used.

The thickness of the charge transport layer is preferably about 5 to 100 μm.

Further, in the present invention, an intermediate layer of polyamide, polyvinyl alcohol, polyvinyl acetal, polyacrylic acid, polyhydroxymethacrylate or the like may be provided between the substrate and the photosensitive layer.

As shown in FIG. 1, these photosensitive layers and intermediate layers are located within the inner area of the aluminum vapor deposition layer and are coated so that the electrical grounding member can be grounded from the same surface as the photosensitive layer coated surface.

The electrical grounding member is grounded to the conductive layer (aluminum layer) deposited on the resin substrate, but the grounding member is
There is no particular limitation as long as it is a conductive material, and the method of grounding may be a structure in which a stainless steel spring shown in FIG. 2 is brought into pressure contact with the conductive layer, or the roller type shown in FIG.

Further, both end surfaces of the cylindrical resin substrate may or may not be opened, and if they are opened, it is necessary to press fit a flange of resin or the like.

FIG. 4 shows a schematic constitutional example of a transfer type electrophotographic apparatus using the electrophotographic photosensitive member of the present invention.

In the figure, reference numeral 1 denotes a drum type photosensitive member of the present invention as an image bearing member, which is rotationally driven around a shaft 1a in a direction of an arrow at a predetermined peripheral speed. The photosensitive member 1 is uniformly charged at its peripheral surface by a charging unit 2 at a predetermined positive or negative potential in the course of its rotation, and then at an exposure unit 3 an optical image exposure L (slit exposure Laser beam scanning exposure). As a result, electrostatic latent images corresponding to the exposed image are sequentially formed on the peripheral surface of the photoconductor.

The electrostatic latent image is then toner-developed by the developing means 4, and the toner development is synchronized by the transfer means 5 between the photoconductor 1 and the transfer means 5 from a paper feeding section (not shown) in synchronization with the rotation of the photoconductor 1. The transfer material P is sequentially transferred onto the surface of the transfer material P that has been taken out and fed.

The transfer material P which has received the image transfer is separated from the surface of the photoconductor and is introduced into the image fixing means 8 where it is subjected to the image fixing and printed out as a copy.

The surface of the photoconductor 1 after the image transfer is cleaned by the cleaning means 6 to remove the residual toner after transfer, and is further discharged by the pre-exposure means 7 to be repeatedly used for image formation.

As the uniform charging means 2 for the photoconductor 1, a corona charging device is generally widely used. In addition, the transfer device 5
Corona transfer means are also widely used. The electrophotographic apparatus is configured by integrally combining a plurality of constituent elements such as the photoconductor, the developing unit, and the cleaning unit described above as an apparatus unit, and the unit is configured to be detachable from the apparatus body. May be. For example, the photoconductor 1
Alternatively, the cleaning unit 6 and the cleaning unit 6 may be integrated into one unit, and may be detachably configured by using a guide unit such as a rail of the apparatus main body. At this time, the above device unit may be provided with a charging unit and / or a developing unit.

When the electrophotographic apparatus is used as a copying machine or a printer, the light image exposure L is reflected light or transmitted light from a document, or a document is read and converted into a signal, and a laser beam is scanned based on this signal. Or driving an LED array or a liquid crystal shutter array.

When the electrophotographic apparatus of the present invention is used as a printer for a facsimile, the light image exposure L becomes an exposure for printing the received data. FIG. 2 is a block diagram showing an example of this case.

The controller 11 controls the image reading section 10 and the printer 19. The entire controller 11 is CP
It is controlled by U17. The read data from the image reading unit 10 is transmitted to the partner station through the transmission circuit 13. The data received from the partner station is sent to the printer 19 through the receiving circuit 12. The image memory 16 stores predetermined image data. The printer controller 18 controls the printer 19. 14 is a telephone.

The image information received from the line 15 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 12, then decoded by the CPU 17, and sequentially stored in the image memory 16. Is stored. When the image information of at least one page is stored in the memory 16, the image recording of that page is performed. The CPU 17 reads out one page of image information from the memory 16 and sends the decoded one page of image information to the printer controller 18. Upon receiving the image information of one page from the CPU 17, the printer controller 18 controls the printer 19 to record the image information of the page.

The CPU 17 is receiving the next page while the printer 19 is recording.

The image is received and recorded as described above.

The electrophotographic photoreceptor of the present invention can be used not only in electrophotographic copying machines but also in laser beam printers, C
RT printer, LED printer, liquid crystal printer,
It can be widely used in electrophotographic application fields such as laser plate making.

[0043]

EXAMPLES Next, examples will be described in detail. Example 1 A non-metallic cylindrical substrate was made of ABS resin. First, AB
S resin is pre-dried at 70 ° C for 4 hours and injection molded (resin temperature 240 ° C, mold temperature 60 ° C, molding pressure 1600kg
/ Cm ² ), the outer diameter is 80 mm, the wall thickness is 1.5 mm,
The length was 363 mm. Next, aluminum was vapor-deposited on the cylindrical substrate to a film thickness of 600 Å to form a conductive layer. Then, a photosensitive layer was provided in the following manner. 10 parts by weight of a disazo pigment having the following structure was dispersed in an amount of 5 parts by weight of polyvinyl butyral resin (S-REC BX-S: Sekisui Chemical Co., Ltd.) and 600 parts by weight of cyclohexanone by a sand mill using glass beads to obtain a charge generation layer coating material. This coating material was applied onto the conductive layer by a usual spray coating method and dried to obtain a charge generation layer having an adhesion amount of 150 mg / m ² .

[0044]

[Chemical 1]

Next, 30 parts by weight of a polycarbonate resin (Z-200 manufactured by Mitsubishi Gas Chemical Co., Inc.) was added to a solution consisting of 300 parts by weight of monochlorobenzene, and a comb type fluorine-based graft polymer (GF-made by Toagosei Kagaku Kogyo Co., Ltd.) was added. 300)
Of 1.2 parts by weight of a fluorochemical surfactant having a nonionic perfluoroalkyl group (Lubron L- manufactured by Daikin Co., Ltd.
2) Dispersed in a ball mill with 0.005 parts by weight, the resulting dispersion, 35 parts by weight of the following stilbene compound, and 5 parts by weight of the above-mentioned polycarbonate resin were dissolved in 1500 parts by weight of monochlorobenzene to obtain a binder resin coating. After being left standing for 10 days, the thickness of the charge transport layer after coating by the ordinary dipping coating method and drying is 25 μm.
m.

[0046]

[Chemical 2]

A flange made of polyacetal was press-fitted into the opening of the cylindrical substrate, and the stainless spring shown in FIG. 2 was grounded from the main body of the electrophotographic apparatus so as to contact the conductive layer (aluminum vapor deposition layer) on the surface of the substrate.

Example 2 Photosensitization was carried out in the same manner as in Example 1 except that the cylindrical resin substrate was made of thermosetting polyester, that is, the polyester obtained by kneading calcium carbonate, silica and glass fibers was made into a cylinder by transfer molding. Created the body. Further, the grounding from the cylindrical substrate was performed by using a metal roller as the material of the developing roller that regulates the distance between the developing device and the photosensitive member.

Example 3 Photosensitization was carried out in the same manner as in Example 1 except that a sheet in which 40% of glass fiber was impregnated with liquid phenolic resin was formed, and the sheet was wound around a predetermined mold and compression-molded to form a cylindrical substrate. Created the body. Further, the grounding from the cylindrical substrate was performed by electrically grounding a member for controlling the distance to the transfer device below the photoconductor.

Comparative Example 1 A cylindrical substrate and a photosensitive member were prepared in the same manner as in Example 1. Further, the flange of the base body opening portion was formed by processing aluminum.

Each of the photoconductors was a machine obtained by modifying Canon's plain paper copying machine NP-3825 to obtain good images.
Although it passed the endurance test up to 10,000 sheets, with the photoreceptor of Comparative Example 1, the aluminum flange could come off in the drop test from a height of 1 m, so it is necessary to improve the accuracy to a dimension where the flange does not come off. occured. Also, 5
Since the flange of Comparative Example 1 sometimes came off when repeatedly stored alternately in an environment of 0 ° C. and −20 ° C., it was necessary to partially bond it with an adhesive.

[0052]

In the electrophotographic photosensitive member and the electrophotographic apparatus having the same of the present invention, the electric grounding of the photosensitive member can be obtained with a simple structure, and the contact between the grounding member and the cylindrical substrate does not consider the dimensional accuracy at all. May be. In addition, since it is not necessary to use a metal flange, the weight can be reduced and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an example of an electrophotographic photosensitive member of the present invention.

FIG. 2 is a schematic cross-sectional view showing an example of a method for grounding the electrophotographic photosensitive member of the present invention.

FIG. 3 is a schematic cross-sectional view showing an example of a method for grounding the electrophotographic photosensitive member of the present invention.

FIG. 4 is a schematic configuration diagram of a transfer type electrophotographic apparatus of the present invention.

FIG. 5 is a block diagram of a facsimile using the electrophotographic apparatus as a printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charging means 3 Exposure part 4 Developing means 5 Transfer means 6 Cleaning means 7 Pre-exposure means 8 Image fixing means 21 Photosensitive layer 22 Intermediate layer 23 Conductive layer 24 Resin base 25 Photoconductor 26 Grounding member 27 Device body 29 Development roller

Claims (3)

[Claims] 1. An electrophotographic photoreceptor having a conductive layer and a photosensitive layer in this order on a non-metallic cylindrical substrate, the same surface as the coated surface of the photosensitive layer being provided by an electrical grounding member attached to the outside of the substrate. An electrophotographic photoreceptor characterized by being grounded from above. 2. An electrophotographic photoreceptor having a conductive layer, an insulating layer and a photosensitive layer in this order on a non-metallic cylindrical substrate, the coated surface of the photosensitive layer being provided by an electrical grounding member attached to the outside of the substrate. An electrophotographic photosensitive member characterized by being grounded from the same surface as the surface. 3. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1.