JP2818569B2 - Photosensitive drum tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive drum tube, and more particularly to a photosensitive drum tube used in an electrophotographic printer, a copying machine, a facsimile, and the like.

[0002]

2. Description of the Related Art Conventionally, an OPC (Organic Photo-Conducte) used for an electrophotographic printer or the like using a laser as a light source.
r, organic photoreceptor) A method of providing an unevenness on the surface of a conductive support in order to prevent interference fringes caused by laser light (Japanese Patent Application Laid-Open Nos. 60-186850 and 60-25)
2359, JP-A-60-256153),
Laser exposure with conductive support surface roughness of 0.3 μm or less
The slope of the surface potential curve uses a laser exposure amount of 1.5 times or more the amount of light at the intersection of the tangent line with the maximum slope and the tangent line with the minimum slope, and the incident angle i of the laser light and the refractive index n of the OPC drum surface layer. Is represented by γ = sin i / n, a method in which γ is 0.05 or more and 0.5 or less (JP-A-3-1022)
No. 68) is known.

In the above-described method of forming irregularities on the surface of the conductive support, local charge injection into the OPC drum is likely to occur, and white spots and black spots may occur as image defects.
In order to eliminate this image defect, it is necessary to provide a barrier layer below the photosensitive layer. However, the application of the barrier layer causes a decrease in productivity and a decrease in yield such as inclusion of foreign matter in the barrier layer.

In addition, the conductive support has a surface roughness of 0.3 μm.
In order to achieve the following, the processing cost such as cutting becomes high, and the laser beam incident on the OPC drum surface expands due to the oblique incident angle of the laser light, causing the resolution to deteriorate, and the laser energy on the OPC drum surface is reduced. Since it becomes smaller, the sensitivity may be reduced, and it may not be applicable to a high-speed machine.

[0005]

The first problem is that, in the prior art, if irregularities are formed on the surface of a conductive support in order to prevent interference fringes caused by laser light, image defects are likely to occur, and a barrier layer is provided. And productivity and yield are degraded. The reason for this is that if the surface of the conductive support is provided with irregularities, local charge injection is likely to occur, causing image defects such as white spots and black spots, which can be prevented by the barrier layer. The reason for this is that the yield deteriorates, for example, in the step of applying the barrier layer and in the contamination of the barrier layer with foreign substances.

The second problem is that the use of a conductive support having a thickness of 0.3 μm or less in order to prevent interference fringes increases the cost of cutting and the like. Is worse. The reason is that making the conductive support 0.3 μm or less increases the cost because of high cutting accuracy, and the laser beam is obliquely incident when obliquely incident.
This is because the laser beam diameter on the surface of the PC drum is widened, and the widened portion deteriorates the resolution on the image.

SUMMARY OF THE INVENTION An object of the present invention is to prevent interference fringe patterns caused by a laser beam, and to solve the problems of image defects, lower productivity, lower yield, higher cost, and lower resolution which have conventionally occurred for the prevention. The present invention is to provide a photosensitive drum base tube that performs the following.

[0008]

Means for Solving the Problems The photosensitive drum tube of the present invention has an anodized film having a film thickness of 5 to 15 .mu.m and a surface roughness of 0.3 to 2 .mu.m using aluminum as the tube material. 1 of 20), and the degree of sealing on the surface of this anodic oxide film is 20 μS to 1600 μS (JIS
H8683 test method).

Further, the photosensitive drum tube of the present invention may be an OPC.
Is a photosensitive drum base tube for applying a coating.

[Operation] The anodic oxide film of the OPC drum tube of the present invention has a surface roughness of 0.3 μm to 2 μm,
When the thickness is 0.3 μm or less, the processing cost increases, and the
If the ratio exceeds the range, there is a possibility that the film thickness unevenness and the image unevenness when the charge generation layer is applied may occur. Further, since the anodized film is an insulating layer, image defects such as white spots and black spots caused by unevenness of the conductive support do not occur.

The anodic oxide film of the present invention has a thickness of 5 μm.
Since the thickness is 15 μm to 15 μm, the reflection intensity of the laser beam is reduced. When the thickness of the anodic oxide film is smaller than 5 μm, the reflection intensity of the laser beam does not decrease. When the thickness is larger than 15 μm, the insulation resistance increases, which may lower the sensitivity and cause image blur.

Furthermore, since the surface of the anodic oxide coating of the present invention has a porosity of 20 μS to 1600 μS, the laser light causes irregular reflection and does not generate interference fringes. When the sealing degree of the surface of the anodic oxide film is smaller than 20 μS, the number of porous portions is reduced and the laser light is hardly irregularly reflected,
Heat resistance is also reduced, and cracks occur even at about 100 ° C. If the degree of sealing is more than 1600 μS, the number of porous portions increases, and foreign matter easily adheres to the surface, and the adhered foreign matter becomes difficult to remove.

[0013]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic view of a photosensitive drum tube according to a first embodiment of the present invention. Referring to FIG. 1, the photosensitive drum blank 1 of the first embodiment has a thickness of 2 m.
m, cylindrical aluminum tube 1 with surface roughness 0.8 μm
Anodizing treatment was performed to obtain a thickness of 7 μm and a surface roughness of 0.
An anodic oxide film 20 having a thickness of 8 μm and a sealing degree of 80 μS was formed.

The photosensitive drum 3 on which the anodic oxide film 20 was formed was coated with a charge generating layer 30 and a charge transport layer 40 thereon by dipping to form a photosensitive drum 3. FIG. 2 shows a schematic diagram thereof. The charge generation layer 30 comprises 2 parts by weight of polyvinyl butyral resin and tetrahydrofuran 9
The coating solution dissolved in 5 parts by weight and dispersed with 3 parts by weight of titanyl phthalocyanine was dried at 70 ° C. for 15 minutes to form a thickness of 0.2 μm. The charge transport layer 40 is composed of 12 parts by weight of a butadiene derivative having the following structural formula and a polycarbonate resin (Z-2).
00: Mitsubishi Gas Chemical) 15 parts by weight of dichloromethane 73
The coating solution dissolved in parts by weight is dried at 120 ° C. for 60 minutes,
A film thickness of 3 μm was formed.

Butadiene derivative

[0017]

FIG. 4 shows the results of black solid printing and white solid printing performed by an electrophotographic printer in which the photosensitive drum 3 has an amount of light of 0.5 mW on the surface of the photosensitive drum and has a laser incident angle of 0 ° where interference is most likely to occur. It is shown in FIG. As shown in FIG. 4, in the first embodiment, neither interference fringes nor image defects occurred.

In the photosensitive drum tube according to the second embodiment of the present invention, the cylindrical aluminum tube 10 having a thickness of 2 mm and a surface roughness of 0.3 μm is subjected to anodizing treatment to obtain a thickness 5 mm.
An anodic oxide film 20 having a thickness of 0.3 μm, a surface roughness of 0.3 μm, and a sealing degree of 20 μS was formed. FIG. 4 shows the result of forming a charge generation layer 30 and a charge transport layer 40 as shown in FIG. 2 on the photosensitive drum tube as in the first embodiment, and performing printing with a similar printer. As shown in FIG. 4, also in the second embodiment, no interference fringes and no image defects occurred.

FIG. 3 is a schematic diagram of a photosensitive drum tube as Comparative Example 1. Referring to FIG. 3, the photosensitive drum blank 2 of this comparative example has a thickness of 2 mm and a surface roughness of 0.3 μm.
Anodizing treatment was performed on the cylindrical aluminum tube 11 having a thickness of 2 μm, a surface roughness of 0.3 μm and a sealing degree of 5 μS. The first photosensitive drum coarse tube
The charge generation layer 40, the charge transport layer 30
FIG. 4 shows the result of printing with the same printer. As shown in FIG. 4, no image defects occurred, but interference fringes did occur.

Further, as Comparative Example 2, anodizing treatment was performed on a cylindrical aluminum tube having a thickness of 2 mm and a surface roughness of 3 μm to obtain a thickness of 25 μm, a surface roughness of 3 μm, and a sealing degree of 175.
An anodized film of 0 μS was formed. FIG. 4 shows the result of forming a charge generation layer 40 and a charge transport layer 30 on the OPC drum tube in the same manner as in the first embodiment, and performing printing with a similar printer. As shown in FIG. 4, no interference fringes were generated, but there were image defects such as density unevenness, blurred image, and missing white image. In addition, as a result of observing the appearance of the OPC drime, it was found that the charge generating layer was missing, probably due to foreign matter on the raw tube.

In the present invention, O
Although the photosensitive drum was formed by applying PC, other types of photosensitive members can be applied.

[0023]

The first effect is that interference fringes due to laser light do not occur. As a result, it is possible to prevent image defects, productivity deterioration, yield deterioration, cost increase, and deterioration in resolution, which have conventionally been problems.

The reason is that, by providing an insulating anodic oxide film on the surface of the conductive support, the reflection intensity of the laser light is reduced by the thickness of the anodic oxide film, and the laser light diffusely reflects due to the porosity of the surface. Wake up and no longer interfere. Further, even if the surface of the conductive support is not processed to a mirror surface, charge injection from the substrate hardly occurs because the anodic oxide film has an insulating film thickness, and image defects do not occur.

[Brief description of the drawings]

FIG. 1 is a schematic view of a photosensitive drum tube according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of a photosensitive drum in which a charge generating layer and a charge transport layer are applied to a photosensitive drum tube.

FIG. 3 is a schematic view of a photosensitive drum tube of Comparative Example 1.

FIG. 4 is a diagram showing the results of an embodiment and a comparative example.

[Explanation of symbols]

 1, photosensitive drum base tube 3 photosensitive drum 10, 11 aluminum base tube 20, 21 anode distribution film 30 charge generation layer 40 charge transport layer

Claims (2)

(57) [Claims] 1. A photosensitive drum tube using an aluminum alloy as a tube material and subjecting the tube to anodizing treatment to form an anodic oxide film having a film thickness of 5 to 15 μm and a surface roughness of 0.3 to 2 μm; In addition, the sealing degree of the surface of the anodic oxide film is 20 μS to 1600 μS (JIS H8863).
Test drum). 2. The photosensitive drum tube according to claim 1, wherein an OPC (Organic Photo-Conducter, an organic photoreceptor) is applied.