JPH0713380A - Electrophotographic photoreceptor and electrophotographic device with it - Google Patents

Abstract

PURPOSE:To provide an electrophotographic photoreceptor, which provides a good image without being affected by multiplex reflection due to a laser beam and can be produced easily at a low cost, and an electrophotographic device provided with this photoreceptor. CONSTITUTION:In an electrophotographic photoreceptor, in which a conductive layer and a photosensitive layer are provided on a nonmetallic cylindrical base body, or a conductive layer, an insulating layer, and a photosensitive layer are provided on a nonmetallic cylindrical base body in this order, while exposure by a laser beam is carried out, the conductive layer is transparent or translucent, the surface of the base body is a light diffusion face, and an electrophotographic device is provided with this photoreceptor. In this way, a good image can be obtained without being affected by multiple reflection due to a laser beam, and the electrophotographic photoreceptor, which can be produced easily at a low cost, and the electrophotographic device provided with this photoreceptor can be obtained.

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 and an electrophotographic apparatus capable of providing 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, as described in JP-A-1-102577 and JP-A-62-279344, by imparting conductivity to the resin substrate and its surface layer, abnormal images and background stains may occur even after repeated use. It is said that it can provide clear and clear images. However, since resin is used for the base, and because metal plating is attached to the base surface as a conductive layer to establish electrical grounding, when laser light enters the photoreceptor, absorption of light inside the photoreceptor is absorbed. Since a large amount of light arrives at the drum base, the light is reflected, reaches the surface of the photoconductor, and is further reflected there. This causes so-called multiple reflection inside the photoconductor.

It is an object of the present invention to provide an electrophotographic photosensitive member and an electrophotographic apparatus having the same, which can suppress the influence of multiple reflection occurring inside the photosensitive member at the time of incidence of the laser light and obtain a high quality image. .

[0008]

That is, the present invention has a conductive layer and a photosensitive layer on a non-metallic cylindrical substrate in this order,
In the electrophotographic photosensitive member which is exposed to a laser beam, the conductive layer is transparent or semitransparent, and the surface of the substrate is a light diffusing surface.

Further, the present invention is an electrophotographic photosensitive member which has a conductive layer, an insulating layer and a photosensitive layer in this order on a non-metallic cylindrical substrate and which is exposed by a laser beam, wherein the conductive layer is transparent or semi-transparent. An electrophotographic photoreceptor, which is transparent and whose surface is a light diffusion surface.

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

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. In addition,
The surface of the resin substrate is processed so as to have a reflectance of 0.6 or less.

Next, if a photosensitive layer is provided directly on the substrate, charging will not occur and the sensitivity will decrease, so it was necessary to provide a metal vapor deposition layer of aluminum or the like in the past. 5 to 500 parts by weight, preferably 5 parts by weight of transparent metal such as tin, aluminum and antimony or fine powder of metal oxide in 100 parts by weight of the binder resin.
˜300 parts by weight dispersed, 10 ¹⁰ Ω or less, preferably 10
Set to ⁶ Ω or less.

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 generation layer is formed of a charge generation material 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 them. 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 generating layer are dissolved or dispersed in a suitable solvent, and the solution is coated on the charge generating 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.

FIG. 1 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 is 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 with the rotation of the photoconductor 1 between the photoconductor 1 and the transfer means 5 from the paper feeding portion (not shown) by the transfer means 5. 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.

After the image transfer, the surface of the photoconductor 1 is cleaned by the cleaning means 6 to remove 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 optical image exposure L is reflected light or transmitted light from a document, or the 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.

[0039]

EXAMPLES Next, examples will be described in detail. Example 1 A non-metal cylindrical substrate was impregnated with 25% by weight of carbon in a resol-type phenol resin, and an outer diameter of 30 mm, a wall thickness of 3.0 mm, and a length of 26 so that the surface reflectance would be 60% or less.
It was molded to 0.5 mm. Next, 100 parts of transparent conductive titanium oxide fine powder (Kronos ECT-62 manufactured by Titanium Industry Co., Ltd.) is used.
100 parts by weight of phenol resin (Priiophen J-325 manufactured by Dainippon Ink and Chemicals, Inc.) was added to 100 parts by weight of methyl cellosolve, and the mixture was rotatably stirred with 1.2φ glass beads on a roll stand for 100 hours. Titanium oxide dispersion on a cylindrical substrate with a dry film thickness of 20 μm
Was applied by dip coating to obtain a conductive layer.

Then, a photosensitive layer was provided in the following manner. 10 parts by weight of a phthalocyanine pigment having the following structure was dispersed in an amount of 5 parts by weight of polyvinyl butyral resin (ESREC 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 .

[0041]

[Chemical 1]

Next, 30 parts by weight of tetrafluoroethylene (Lubrone L-2 manufactured by Daikin Co., Ltd.) was added to a solution consisting of 30 parts by weight of a polycarbonate resin (Z-200 manufactured by Mitsubishi Gas Chemical Co., Inc.) and 300 parts by weight of monochlorobenzene. , Comb type fluorine-based graft polymer (GF-3 manufactured by Toagosei Kagaku Kogyo Co., Ltd.
00) together with 1.2 parts by weight and 0.005 parts by weight of a fluorosurfactant having a nonionic perfluoroalkyl group (Unidyne DS-406 manufactured by Daikin Co., Ltd.) in a ball mill and dispersed. 35 parts by weight of the above stilbene compound, the same as the above-mentioned polycarbonate resin 5
One part by weight was dissolved in 1500 parts by weight of monochlorobenzene to obtain a binder resin coating, which was allowed to stand still for 10 days and then applied by an ordinary dipping coating method to obtain a charge transport layer having a thickness of 25 μm after drying.

[0043]

[Chemical 2]

Example 2 A cylindrical resin substrate is produced from thermosetting polyester, that is, polyester obtained by kneading calcium carbonate, silica and glass fibers is made into a cylinder by transfer molding,
A conductive layer similar to that in Example 1 was created. Next, as an intermediate layer between the conductive layer and the photosensitive layer, a polyamide resin (resin E
F-30T) 50 parts by weight, methyl alcohol 400 parts by weight and butyl alcohol 200 parts by weight were dissolved in a mixed solvent and dip-coated to form a 0.5 μm intermediate layer. Next, a photosensitive member was prepared as a photosensitive layer in the same manner as in Example 1.

Example 3 Liquid phenolic resin with 15% carbon and 40 glass fibers
% Impregnated to form a cylindrical substrate, and the conductive layer and the intermediate layer were formed in the same manner as in Example 2.

Next, for the photosensitive layer, 5 parts by weight of the above-mentioned phthalocyanine, 50 parts by weight of the above-mentioned stilbene compound and 50 parts by weight of the above-mentioned polycarbonate resin are dissolved and dispersed in 500 parts by weight of cyclohexanone, and coated on the intermediate layer, The film thickness after drying as a single-layer photoreceptor was 25 μm.

Comparative Example 1 A photoconductor was prepared in the same manner as in Example 1 except that an aluminum cylinder was used instead of the non-metallic cylindrical substrate.

Comparative Example 2 A photoreceptor was prepared in the same manner as in Example 1 except that an aluminum film was vapor-deposited on the cylindrical substrate to form a conductive layer instead of using transparent conductive powder for the conductive layer.

The evaluation of each photoconductor was carried out by an image of a laser printer LBP-SX manufactured by Canon.

Evaluation results In Comparative Examples 1 and 2, so-called interference fringes, which were affected by multiple reflections, were generated in the gray image. In Examples 1, 2 and 3, high quality images were obtained without the above-mentioned image defects.

[0051]

INDUSTRIAL APPLICABILITY In the electrophotographic photosensitive member of the present invention and the electrophotographic apparatus having the same, a good image can be obtained without being affected by multiple reflection by laser light, and a conventional metal vapor deposition layer can be formed. It is possible to use existing equipment such as dip coating and spray coating, which does not need to be created and is excellent in mass productivity, and it is possible to provide it at low cost.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a transfer type electrophotographic apparatus of the present invention.

FIG. 2 is a block diagram of a facsimile using the electrophotographic apparatus as a printer.

[Explanation of symbols]

 1 Photoreceptor 2 Charging Means 3 Exposure Part 4 Developing Means 5 Transfer Means 6 Cleaning Means 7 Pre-Exposure Means 8 Image Fixing Means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takao Soma 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (3)

[Claims] 1. An electrophotographic photoreceptor having a conductive layer and a photosensitive layer in this order on a non-metallic cylindrical substrate, and the conductive layer is transparent or semi-transparent, and the substrate is An electrophotographic photosensitive member characterized in that the surface thereof is a light diffusing surface. 2. An electrophotographic photoreceptor having a conductive layer, an insulating layer and a photosensitive layer in this order on a non-metallic cylindrical substrate, and the conductive layer is transparent or semi-transparent, An electrophotographic photosensitive member characterized in that the surface of the substrate is a light diffusing surface. 3. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1.