JPH06118679A - Cylindrical base body for electrophotographic sensitive body and its production - Google Patents

Abstract

PURPOSE:To prevent the generation of longitudinal striae patterns on a print by removing the surface layer of a pipe of a prescribed length obtd. by extrusion processing of a mandrel and subjecting this mandrel to drawing. CONSTITUTION:The mandrel pipe obtd. by hot extrusion processing is previously cut to the required length. The extrusion processed and cut pipe is elongated in length about 3 times by the drawing. Then, the treatment area is decreased to about 1/3 as compared with the treatment to be executed after the drawing if the outside surface cutting is executed before the above-mentioned drawing. The treatment is thus executed at a low cost. The cutting of the outside surface of the mandrel pipe is then executed. The cutting depth is adjusted according to an unequal thickness quantity. The cylindrical base body is obtd. by the drawing after the mandrel pipe is adjusted in the unequal thickness and after the surface defects on the outside surface are removed. The generation of the longitudinal striae patterns on the print does not arise even with the cylindrical base body which is merely provided with the photosensitive layer without providing the surface thereof with an under coating layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical substrate for an electrophotographic photoreceptor and a method for producing the same.

[0002]

BACKGROUND OF THE INVENTION As a method for manufacturing a cylindrical substrate for an electrophotographic photosensitive member made of aluminum or an aluminum alloy (hereinafter, aluminum), extrusion is conventionally performed using a die called a hollow die which is a combination of a front die and a back die. A technique has been proposed in which the processed porthole extruded pipe is subjected to a drawing process, then cut to a predetermined length, and then the outer surface is cut and finished using a cutting tool such as a diamond bite.

However, since the cylindrical substrate (DT tube) for an electrophotographic photosensitive member thus obtained has a high cost, it is for an electrophotographic photosensitive member in which the surface of a porthole extruded tube is finished by ironing. Cylindrical substrate (EI tube)
Alternatively, a cylindrical substrate (ED tube) for an electrophotographic photoreceptor obtained by cold drawing has been proposed. By the way, a photosensitive layer is provided on the surface of the EI tube or the ED tube to manufacture an electrophotographic photosensitive member, and a vertical streak-like pattern is recognized in a copied image printed using the electrophotographic photosensitive member, and a good print is obtained. It has been pointed out that there is no.

Therefore, in order to solve such a problem, E
An electrophotographic photoreceptor has been proposed in which an undercoat layer is provided on the surface of an I tube or an ED tube, and a photosensitive layer is provided on the undercoat layer. However, such means is not satisfactory because the purpose of cost reduction is largely lost.

[0005]

DISCLOSURE OF THE INVENTION As a result of intensive research to address the above-mentioned problems, it has been found that the vertical streak pattern is occurring in the welded part of aluminum called weld line. That is, when a pipe is extruded using a hollow die, the aluminum is first divided by the port and re-welded under the bridge into a hollow pipe. Therefore, in a pipe manufactured by using a hollow die, several welded parts of aluminum called weld lines are formed in the longitudinal direction. By the way, in the vicinity of the weld line, a change in the crystal structure occurs, or oxides are involved, so that the electrical properties of the substrate are changed in the vicinity of the weld line. It was discovered that a vertical streak defect had occurred.

In order to solve the above-mentioned image defects, it has been found that a pipe should be manufactured by a means in which no weld line is formed. That is, we have come to the knowledge that the production of image defects as described above can be solved by producing a pipe by mandrel extrusion. However, the pipe obtained by the mandrel extrusion process (mandrel pipe) is not satisfactory.

That is, although the mandrel tube has no weld line as compared with the porthole extruded tube, it has an uneven thickness of about 0.1 to 0.3 mm, and if it is ironed or drawn, Since the tube processed due to the flesh had a large bend, it could not be used at all as a cylindrical substrate for an electrophotographic photoreceptor. Therefore, it is necessary to add a straightening process such as roller straightening, which results in high cost. In particular, even if a normal degree of correction is applied, it is not sufficient, and therefore, if the correction is more than sufficient so that it can be used as a cylindrical substrate for an electrophotographic photoreceptor, the cost will be very high.

The present invention has been achieved on the basis of such knowledge, and an object of the present invention is to provide a cylindrical substrate for an electrophotographic photoreceptor at a low cost, in which vertical stripe-like patterns do not occur in prints. It is to provide the technology obtained in. The object of the present invention is achieved by a cylindrical substrate for an electrophotographic photosensitive member, characterized in that a surface layer of a pipe having a predetermined length obtained by mandrel extrusion is removed and ironing is performed.

Further, a mandrel extrusion process for producing a pipe by mandrel extrusion, a cutting process for cutting the pipe obtained by the mandrel extrusion process to a predetermined length, and a predetermined length obtained by the cutting process. A method for producing a cylindrical substrate for an electrophotographic photosensitive member, comprising: a removing step of removing a surface layer of a pipe; and an ironing step of ironing the pipe having the surface layer obtained in the removing step. Achieved by

In the above invention, the removal depth of the pipe surface layer is preferably about 0.1 mm or more and about 0.3 mm or less. It is sufficient to remove about 0.5 mm at the maximum. As the surface layer removing means, for example, a cutting tool such as a diamond bite, an etching process, a blasting process, a polishing process or the like can be appropriately used, but a cutting device is preferable from the viewpoint of uniform cutting property and cost.

The present invention will be described in detail below. First, a mandrel tube is obtained by hot extrusion. And
The length of this mandrel tube required for EI processing (for example, 8
It is cut in advance to about 0 to 120 mm). As a result, the cost of cutting the outer surface layer performed thereafter becomes low. That is, the extruded and cut pipe is
The length is extended about 3 times by ironing. Therefore,
If the outer surface layer cutting process is performed before the ironing process, the processing area can be reduced to about 1/3 of that performed after the ironing process, and the process can be performed at low cost.

Next, the outer surface layer of the mandrel tube is cut. This outer surface layer can be cut using a cutting tool such as a diamond cutting tool. The cutting depth is about 0.1 to 0.3 mm depending on the amount of uneven thickness, and about 0.3 to 0.5 mm when the amount of uneven thickness is large. Then, after the uneven thickness of the mandrel tube is adjusted by the appropriate means described above and after the surface defects on the outer surface are removed, the cylindrical substrate for an electrophotographic photoreceptor is obtained by ironing.

The thus produced cylindrical substrate for an electrophotographic photosensitive member has a vertical streak pattern on a print even if a photosensitive layer is provided on the surface thereof without providing an undercoat layer. , A good print is obtained, and its manufacturing cost is low. There is no particular restriction on the aluminum material used for the cylindrical substrate for the electrophotographic photoreceptor, but 1100, 3003, 60
63 alloy etc. are mentioned as a preferable example.

A specific description will be given below with reference to examples.

[0015]

【Example】

[Example 1] A mandrel extrusion process was performed on an aluminum (JIS 3003) material to produce a mandrel tube having an outer diameter of 32 mmφ and a wall thickness of 6 mm.
Cut into

Then, the outer surface layer of the mandrel tube is cut with a diamond bite to a depth of 0.2 mm from the surface, and thereafter ironed to give an outer diameter of 30 mm.
A cylindrical substrate for an electrophotographic photosensitive member having φ, a wall thickness of 1 mm and a length of 260 mm was obtained. [Comparative Example 1] Aluminum (JIS 3003) material is machined using a hollow die to have an outer diameter of 32 mmφ.
Then, a porthole extruded tube having a wall thickness of 6 mm was produced and cut into a length of 100 mm.

Then, the outer surface layer of the porthole extruded pipe is cut with a diamond bite to a depth of 0.2 mm from the surface, and thereafter ironed to give an outer diameter of 30.
A cylindrical substrate for an electrophotographic photosensitive member having an mmφ, a wall thickness of 1 mm and a length of 260 mm was obtained. [Comparative Example 2] Aluminum (JIS 3003) material was machined using a hollow die to give an outer diameter of 32 mmφ.
A port-hole extruded tube having a wall thickness of 6 mm was prepared by cutting with a length of 300 mm.

After cold drawing, it is cut into a length of 260 mm, an outer diameter of 30 mmφ, a wall thickness of 1 mm,
A 260 mm long cylindrical substrate for an electrophotographic photosensitive member was obtained. [Comparative Example 3] An aluminum (JIS 3003) material was extruded by a mandrel to produce a mandrel tube having an outer diameter of 32 mmφ and a wall thickness of 6 mm.
It was cut into mm.

After cold-drawing, it is cut into a length of 260 mm, an outer diameter of 30 mmφ, a wall thickness of 1 mm,
A 260 mm long cylindrical substrate for an electrophotographic photosensitive member was obtained. [Characteristics] A cylindrical substrate for an electrophotographic photoreceptor obtained in each of the above examples was coated with a photosensitizer to prepare an electrophotographic photoreceptor, and the characteristics of an image copied by an apparatus incorporating the same were examined. The results are shown in Table 1. In addition, we have also examined the corofle, which is also shown in Table 1.

[0020] In the image characteristics, the ⊚ mark does not show streak-shaped image defects, and the X mark shows streak-shaped image defects. ◎ mark in Korofure is less than 30 μm × mark is 60 μm or more

[0021]

According to the present invention, a cylindrical substrate for an electrophotographic photosensitive member can be obtained at a low cost, which can provide excellent image quality without the occurrence of vertical stripe patterns.

Claims (4)

[Claims] 1. A cylindrical substrate for an electrophotographic photosensitive member, characterized in that the surface layer of a pipe having a predetermined length obtained by mandrel extrusion is removed and ironed. 2. The removal depth of the pipe surface layer is about 0.1 mm.
The above is the cylindrical substrate for an electrophotographic photosensitive member according to claim 1. 3. A mandrel extrusion process for producing a pipe by mandrel extrusion, a cutting process for cutting the pipe obtained by the mandrel extrusion process into a predetermined length, and a predetermined length obtained in the cutting process. A method for producing a cylindrical substrate for an electrophotographic photosensitive member, comprising: a removing step of removing a surface layer of a pipe; and an ironing step of ironing the pipe having the surface layer obtained in the removing step. . 4. The method for manufacturing a cylindrical substrate for an electrophotographic photosensitive member according to claim 3, wherein the removal depth in the removing step is about 0.1 mm or more.