JPH0594032A - Method for manufacturing aluminum base for photosensitive drum - Google Patents

Abstract

(57) [Summary] [Purpose] Even non-cutting aluminum pipes have excellent smoothness with no wrinkles or rustles on the surface, enabling uniform coating of the photosensitive layer and improving image quality. A possible aluminum substrate for a photosensitive drum is manufactured. [Structure] A non-cutting aluminum tube that has been subjected to a drawing or ironing process is used, and the surface of the aluminum tube is groundlessly ground to remove wrinkles, creases, and the like on the surface. Next, the surface of the aluminum tube which has been subjected to the centerless grinding is chemically etched to remove the abrasive grains embedded in the surface of the tube. Next, the aluminum tube is anodized to form an anodized film on its surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an aluminum substrate used as a photosensitive drum of a PPC copying machine, a laser beam printer or the like, and particularly to an organic photosensitive drum (so-called OPC photosensitive drum) using an organic material as a photosensitive layer. The present invention relates to a method for manufacturing an aluminum substrate suitable for use.

In this specification, the term aluminum is used to include its alloy.

[0003]

2. Description of the Related Art Generally, an electrophotographic photosensitive member is constituted by a conductive support made of aluminum coated with a photosensitive layer. As the photosensitive layer, an inorganic photoconductive material such as selenium is used. Organic photoconductors using organic materials (so-called OPC photoconductors) have come to be used because of their excellent film-forming properties, light weight, low cost, and the like.

Recently, in order to further improve the function and characteristics of the organic photoreceptor, the photosensitive layer is recently replaced with a charge generation layer (CG).
L) and a charge transport layer (CTL) are provided, and an organic photoreceptor called a laminated type is provided.

By the way, the aluminum tube used for such a photosensitive drum has been required to have higher surface smoothness than before in order to exhibit excellent image characteristics. Charge generation layer is usually 1 μm
Since it is applied to the following thickness, further surface smoothness is required from the viewpoint of image quality.

For this reason, conventionally, in the case of a photosensitive drum for a laser beam printer, which is required to have high quality and high image, a machined product which is easy to obtain a smooth and uniform surface is often used as an aluminum substrate. ..

[0007]

However, in such a machined product, since the surface of the aluminum tube is mirror-finished by machining, it is not easy to adjust and manage the cutting tool, and the skill is required for the work. It is not suitable for mass production, and there is a problem that it is difficult to reduce the price of drums.

Therefore, recently, non-cutting aluminum pipes such as an aluminum pipe called an EI pipe manufactured by an extrusion / ironing process and an aluminum pipe called an ED pipe manufactured by an extrusion / drawing process are used. It is used as a photosensitive drum substrate.

[0009] However, although such a non-cutting aluminum pipe does not require cutting, the cost can be reduced. However, since the surface of the aluminum pipe has defects such as wrinkles and creases at the time of drawing, a charge generation layer. However, it is difficult to uniformly coat the photosensitive layer, and a new defect is caused that uneven density occurs in a solid image (halftone).

The present invention has been made in view of the above technical background, and even non-cutting aluminum pipes such as EI pipes and ED pipes are excellent in smoothness without surface wrinkles and rustles. Therefore, it is an object of the present invention to manufacture and provide an aluminum substrate for a photosensitive drum, which enables uniform coating of a photosensitive layer and improves image quality.

[0011]

In order to achieve the above object, the present invention uses a non-cutting aluminum tube that has undergone a drawing or ironing step, and performs a centerless grinding of the surface of the aluminum tube, and a centerless grinding. And a step of chemically etching the surface of the finished aluminum tube and a step of anodizing the etched aluminum tube to form an anodized film on the surface of the aluminum tube. The gist of the present invention is a method of manufacturing a substrate.

The above-mentioned drawing or ironing step applied to the aluminum tube that has undergone the steps such as extrusion may be carried out under the conditions according to the conventional method. In the drawing or ironing process, defects such as wrinkles and rustles occur on the surface of the aluminum tube.

Therefore, in the present invention, after ironing or drawing, the surface of the aluminum tube is subjected to centerless grinding (centerless grinding). This centerless grinding is a well-known method suitable for surface grinding of a cylindrical tube, and the outer surface of the aluminum tube is supported by an adjusting grindstone and a support plate without supporting the center hole of the aluminum tube, and the rotary feed motion of the aluminum tube is supported by the adjusting grindstone. It is a method of adjusting and grinding the surface of the aluminum tube with a grinding wheel. By performing such centerless grinding, wrinkles and creases on the surface of the aluminum tube are removed and the surface roughness is improved.

After the centerless grinding, the surface of the aluminum tube is chemically etched. This etching is carried out in order to further improve the surface smoothness by removing the abrasive grains embedded in the surface of the aluminum tube in the centerless grinding step. The etching treatment conditions are not particularly limited, but a caustic etching method of immersing in an aqueous solution of sodium hydroxide (NaOH) or a method of immersing in an aqueous solution of sodium carbonate (Na2 CO3) can be mentioned in consideration of the simplicity of the treatment. Regarding the conditions such as the processing time, the conditions that can dissolve and remove the abrasive grains on the surface of the aluminum tube may be appropriately set. If necessary, a pretreatment such as degreasing may be performed before etching.

Next, if necessary, the aluminum tube that has been subjected to the etching treatment is washed with water, neutralized and the like, and then anodized. The reason for applying the anodizing treatment is to improve the adhesion between the photosensitive layer and the aluminum tube by the anodized film and to improve the charge injection preventing property. The type of the anodizing treatment is not particularly limited, and a sulfuric acid method using sulfuric acid as an electrolytic solution or an oxalic acid method using oxalic acid may be used. The thickness of the anodic oxide film is not particularly limited, but is preferably about 1 to 20 μm. If it is less than 1 μm, the adhesiveness to the photosensitive layer and the charge injection preventing property may be deteriorated. On the other hand, even if the thickness exceeds 20 μm, it is not possible to expect an increase in these effects, but rather there is a risk of causing a decrease in productivity due to an increase in processing energy and processing time.

The aluminum tube which has been subjected to the above anodic oxidation treatment is then subjected to treatment such as washing with water, and more preferably, after sealing treatment using a nickel sulfate solution, a photosensitive layer is coated to form a desired photosensitive material. Play as a drum.

[0017]

Embodiments of the present invention will be described below.

Using an ED tube having a diameter of 30 mm and a length of 260.5 mm made of an A3003 alloy, the surface finishing method was changed in various ways as shown below to produce a total of six aluminum substrates No. 1 to No. 6.

(No. 1) ED tube as it is.

(No2) A mirror-finished ED tube. The mirror surface processing was performed by attaching a 5R Compax R bite to a precision lathe and cutting at a rotation speed of 2300 rpm.

(No. 3) An ED tube subjected to centerless grinding. The centerless grinding was performed by setting a grinding wheel and an adjusting grindstone on a centerless grinder, setting the peripheral speed of the grindstone to 1800 m / min, and injecting grinding oil.

(No. 4) The same ED tube as the above No. 1 was sequentially subjected to chemical etching treatment and anodizing treatment. These treatments include degreasing (surfactant), etching (NaOH: 50g / l, 30 ° C x 30 seconds), water washing, neutralization (nitric acid: 13w / v%), water washing, anodizing treatment (sulfuric acid: 14w). / V%, 20 ° C, 1.0A / dm2 x 3
0 minutes) · Washing with water · Sealing (nickel acetate: 10 g / l, 70
(° C. × 20 minutes), washing with water, and then drying.
The thickness of the anodized film was 8 μm.

(No. 5) A mirror-finished product like No. 2 and then a chemical etching process and an anodizing process under the same conditions as No. 4.

(No. 6) A centerless grinding like No. 3 and then a chemical etching treatment and an anodic oxidation treatment under the same conditions as No. 4.

Next, the surface roughness of each of the aluminum substrates obtained above was measured, and it was as shown in Table 1.

Then, a photosensitive layer having a charge generation layer and a charge transport layer was formed on each aluminum substrate by coating as follows. That is, the CGL layer has a film thickness of about 0.
It was formed by coating and drying so as to have a thickness of 5 μm. Then C
The T agent (hydrazone compound) and the CT resin (polycarbonate) were dissolved in methylene chloride at a ratio of 1: 2, coated so as to have a film thickness of about 20 μm, and dried to form a CTL layer.

Next, the image evaluation of these photoconductors was carried out by a commercial copying machine. The results are also shown in Table 1.

[0028]

[Table 1]

From the results shown in Table 1 above, the product No. 6 manufactured according to the present invention had surface roughness and image quality comparable to those of the conventional product No. 5 manufactured by the mirror surface grinding process.

Therefore, it was confirmed that the present invention, which does not require a cutting step, is advantageous in terms of manufacturing simplicity, cost and the like.

[0031]

As described above, the present invention uses a non-cutting aluminum tube that has been subjected to a drawing or ironing step to perform a centerless grinding of the surface of the aluminum tube and a surface of the aluminum tube after the centerless grinding. It is characterized by carrying out a step of chemical etching treatment and a step of anodizing the etched aluminum tube to form an anodized film on the surface thereof, so that a cutting step is not required. However, it is possible to exhibit the same image characteristics as those obtained by finishing the surface of the aluminum tube by cutting. As a result, not only adjustment or management of a cutting tool for cutting work becomes unnecessary or simple, but also skill of operation is not required, so that mass production becomes possible, which contributes to lowering the price of the drum.

Claims (1)

[Claims] 1. A step of performing a centerless grinding of the surface of the aluminum tube using a non-cutting aluminum tube that has been subjected to a drawing or ironing step, and a step of chemically etching the surface of the aluminum tube after the centerless grinding, And a step of forming an anodized film on the surface of the aluminum tube that has been subjected to the etching treatment, thereby forming an aluminum substrate for a photosensitive drum.