JPH02201373A - Production of photosensitive body - Google Patents

Abstract

PURPOSE:To improve image reliability and repetitive stability by rubbing a conductive base body for the photosensitive body with brushes in a solvent and cleaning the base body. CONSTITUTION:The conductive base body 1 is immersed into a cleaning tank 3 in which the solvent 2 is housed. The outer and inner peripheral surfaces of the conductive base body 1 are rubbed by a pair of the large and small brushes 4, 5 provided in this cleaning tank 3, by which the conductive base body is cleaned. The foreign materials, such as dust, dirt, fine metallic pieces, rust and oil, sticking to the outside and outside surfaces of the conductive base body 1 are, therefore, sufficiently removed. Further, the generation of defects in the photosensitive layer formed on the conductive base body 1 is suppressed. The generation of image defects and defective cleaning is thus obviated. The high image reliability and repetitive stability are obtd. in this way.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for manufacturing a photoreceptor used in electrophotographic devices such as copying machines and printers, and in particular, a method for manufacturing a conductive substrate before forming a photosensitive layer. It is characterized by its cleaning method.

[Prior art and its problems] Conventionally, when manufacturing photoreceptors for use in electrophotographic devices such as copying machines and printers, conductive substrates for photoreceptors are formed by mechanical processes. After cleaning this, a photosensitive layer is formed on this conductive substrate.

Here, such photoreceptors have basic characteristics such as charge retention, high sensitivity, repetition stability, dielectric breakdown resistance, abrasion resistance, durability, moisture resistance, transferability, cleaning performance, and storage stability. Furthermore, in recent years, as such photoreceptors have come to be used in laser printers, etc., high image reliability and repeat stability are also required during reversal development. It became so.

Therefore, conventionally, in such photoreceptors,
Various studies have been made regarding materials for the photosensitive layer formed on the conductive substrate.

In such photoreceptors, inorganic photoconductive materials such as selenium, zinc oxide, titanium oxide, and cadmium sulfide have been generally used as materials constituting the photosensitive layer, and organic photoconductive materials have also been used. Polymer materials also began to be used.

However, photoreceptors using inorganic photoconductive materials are generally highly toxic and have problems with moisture resistance, etc.
Photoreceptors using organic photoconductive materials have not yet been able to provide sufficient sensitivity and have been insufficient in terms of durability and stability against environmental changes.

For this reason, in recent years, functionally separated photoreceptors, such as laminated or dispersed types, have been developed in which the functions of charge generation and charge transport in the photoreceptor are assigned to separate substances. Ta.

As described above, various studies have been made on the photosensitive layer formed on the conductive substrate, but in order to obtain higher image reliability and repeat stability in any of these photoreceptors, it is necessary to In addition, there were major problems with the conductive substrate on which the photosensitive layer was provided.

That is, since such a conductive substrate is produced by a mechanical process, the outer and inner surfaces of the conductive substrate are coated with
Dust, dirt, metal particles, rust.

If foreign matter such as oil is attached and the photosensitive layer is formed without sufficiently removing it, the formed photosensitive layer may have defects.
+"4, which caused problems such as image defects and poor cleaning.

In order to remove the above-mentioned foreign substances from the conductive substrate, it has conventionally been possible to wash the above-mentioned conductive substrate with an organic solvent such as trichlene, or with an acid solution or an alkaline solution. This is commonly practiced, and Japanese Patent Application Laid-Open No. 157687/1983 discloses a method of etching a conductive substrate by a specified amount using an alkaline solution.

However, simply cleaning the conductive substrate with an organic solvent as described above only removes the oil adhering to the conductive substrate, and cleaning the surface of the conductive substrate with an acid solution or alkaline solution and etching In this case, there is a problem in that the smoothness of the surface of the conductive substrate is impaired, which may even lead to image defects.

Furthermore, in any of these methods, fine dust and metal particles adhering to the conductive substrate cannot be sufficiently removed, and there is a problem in that black spots appear on blank areas, especially during reversal development. .

[Problems to be Solved by the Invention] An object of the present invention is to solve the above-mentioned problems in manufacturing a photoreceptor used in an electrophotographic apparatus.

That is, the present invention deals with dust adhering to the outer and inner surfaces of a conductive substrate produced by a mechanical process when manufacturing a photoreceptor by forming a photosensitive layer on the surface of the conductive substrate.
Garbage, metal particles.

It sufficiently removes foreign substances such as rust and oil, suppresses defects from occurring in the photosensitive layer formed on the conductive substrate, and prevents image defects, cleaning failures, and bending.
It is an object of the present invention to provide a photoreceptor that has high image reliability and repeat stability, and that produces fewer black spots in blank areas during reversal development.

[Means and effects for solving the problem] In order to solve the above-mentioned problems, the present invention provides a method for cleaning a conductive substrate for a photoreceptor by rubbing it with a brush in at least a solvent, and then cleaning the conductive substrate by rubbing it with a brush in at least a solvent. A photosensitive layer was formed on the substrate.

In this way, when a conductive substrate for a photoconductor manufactured by a mechanical process is cleaned by rubbing it with a brush in a solvent, in addition to the oil adhering to the conductive substrate, dust, Even fine foreign matter such as dust, metal particles, and rust can be sufficiently removed, and the occurrence of defects in the photosensitive layer formed on the conductive substrate is suppressed.

Here, the conductive substrate used in this invention may be of any material as long as it is made of various materials such as aluminum that are generally used for photoreceptors, and its shape may also be It may have any shape such as a shape, a plate shape, a belt shape, etc.

When brush cleaning such a conductive substrate in a solvent, the solvent may be pure water, chlorinated aliphatic hydrocarbons such as dichloromethane, dichloroethane, trichloroethane, trichlorethylene, perchlorethylene, etc. Fluorine-based aliphatic hydrocarbons such as freon, toluene.

Aromatic hydrocarbons such as xylene, ketone solvents such as methyl ethyl ketone and acetone, cyclic ether solvents such as tetrahydrofuran, alcohols such as methanol, ethanol, and isopropanol, and acetic acid esters such as ethyl acetate butyl diacetate. Among these solvents, it is particularly preferable to use those having a boiling point of 100° C. or lower from the viewpoint of drying conditions.

In addition, the brush used for this brush cleaning can be made of materials such as rayon, nylon, acrylic, polyester, polypropylene, Teflon (trade name), synthetic fibers thereof, animal hair, etc. In particular, if it is hard, it may damage the conductive substrate.
It is preferable to use materials such as nylon, polyester, and animal hair, and it is further desirable to use materials that have been subjected to conductive treatment.

Also, this brush usually has a pile length of 5
~50 mm, with a pile thickness of 2.5 to 30.0 deniers, preferably 3 to 10 deniers, and a pile density of:
Although it is related to the thickness of the pile, it is preferable that it is dense, and preferably 100 piles/crd or more.

Furthermore, in order to more thoroughly clean the conductive substrate, it is preferable to combine the above-mentioned cleaning with a brush with another cleaning method. or immersion in an organic solvent.

It is more preferable to perform cleaning by immersion in pure water and an organic solvent in this order, and to perform ultrasonic cleaning at the same time as the cleaning with the brush.

When manufacturing a photoreceptor by forming a photosensitive layer on the conductive substrate after cleaning the conductive substrate by rubbing it with a brush in a solvent as described above, the material constituting the photosensitive layer is Inorganic.

Any organic photoconductive material may be used, and the layer state and formation method of the photosensitive layer are not particularly limited.

Further, it is also possible to provide an undercoat layer or the like in order to enhance the adhesion and blocking properties of the photosensitive layer to the conductive substrate.

[Example] Hereinafter, the method for manufacturing a photoreceptor according to each example of the present invention will be explained in detail based on the attached drawings, and comparative examples will be given to explain the method for manufacturing a photoreceptor according to each example. It will be revealed that the photoreceptor is superior.

(Example 1) In this example, a circular conductive substrate made of aluminum alloy with an outer diameter of 8 mm, an inner diameter of 76 mm, and a length of 320 mm is used. It was lathed and finished to a mirror finish.

Next, in this example, before cleaning the conductive substrate mirror-finished as described above by rubbing it with a brush in a solvent, the conductive substrate was placed in a 40°C Triclean bath and a 40°C pure water bath. , a 40° C. Triclean tank, and a 40° C. pure water tank, and were immersed in each tank for 2 minutes for pre-cleaning.

When cleaning the pre-cleaned conductive substrate by rubbing it with a brush in a solvent, as shown in FIG. A pair of large and small brushes (4), (
According to 5).

The outer circumferential surface and inner circumferential surface of this conductive substrate (1) were rubbed and cleaned.

In this embodiment, the cleaning tank (3) is filled with trichloride solution as the solvent (2) and maintained at 40°C, and the pair of large and small brushes (4) and (5) shown in F are ,
Large and small nylon brushes each having a pile length of 10 mm and a pile thickness of 5 denier were used.

Then, the conductive base (1) is placed in the cleaning tank (3) so that the conductive base (1) covers the outer periphery of the small-diameter brush (5).
) and the pair of large and small brushes (4) and (5) mentioned above.
are rotated by a first motor (6) via a belt (7) at a rotation speed of 30 rpm each, while the conductive substrate (1) is rotated by a second motor (8) between these brushes (4). .

Rotate in the opposite direction to (5) at a rotation speed of 15 rpm,
The outer circumferential surface of the conductive substrate (1) was rubbed with a large-diameter brush (4), and the inner circumferential surface of the conductive substrate (1) was rubbed with a small-diameter brush (5) to perform cleaning for 1 minute.

Next, the conductive substrate cleaned with a brush as described above was left in a cooling tank for 30 seconds, and then this conductive substrate was steam-cleaned for 1 minute in a 90°C Tri-Clene steam bath. The substrate was cooled.

A dispersion in which a charge generating material consisting of a bisazo pigment represented by the following chemical formula [N] is dispersed is applied to the conductive substrate thus cleaned, and this is dried to form a charge on the conductive substrate. A generation layer was formed.

[I] Next, on the charge generation layer thus formed, a coating solution containing a charge transporting material made of a hydrazone compound represented by the following chemical formula [11] and a polycarbonate resin is applied, and this is dried. A charge transport layer was formed, and a functionally separated laminated photoreceptor was produced in which a charge generation layer and a charge transport layer were laminated on a conductive substrate.

(Example 2) In this example, the conductive substrate was mirror-finished in the same manner as in Example 1, and before being cleaned by rubbing with a brush in a solvent, The conductive substrate was pre-cleaned in the same manner as in Example 1 above.

In this example, when cleaning the pre-cleaned conductive substrate by rubbing it with a brush in the solvent, the solvent (2
), 1,1,2-trichloro-1,2,2-)rifluoroethane (Freon TF) was stored at 35°C, and a pair of large and small brushes (4) and (5
), large and small polyester brushes with a pile length of 30 mm and a pile thickness of 8 denier and conductive treated were used.

The pair of large and small brushes (4) and (5) are rotated by the first motor (6) at a rotation speed of 30 rpm, while the conductive substrate (1) is rotated by the second motor (8).
These brushes (4) by.

Rotate in the opposite direction to (5) at a rotation speed of 20 rpm,
The outer peripheral surface of the conductive substrate (1) is rubbed with a large-diameter brush (4), and the inner peripheral surface of the conductive substrate (1) is rubbed with a small-diameter brush (5) for 5 minutes. (3) The ultrasonic generator (9) provided in the
Ultrasonic cleaning was performed using kHz ultrasound for 1 minute and 45 kHz ultrasound for 1 minute.

After leaving the conductive substrate thus cleaned in a cooling tank for 30 seconds, the conductive substrate was
After steam cleaning for 1 minute in a Freon TF steam bath at °C, the conductive substrate was allowed to cool.

Then, a charge generation layer and a charge transport layer were formed on the conductive substrate thus cleaned in the same manner as in Example 1, to produce a functionally separated laminated photoreceptor.

(Comparative Example) In this comparative example, the step of cleaning the conductive substrate by rubbing it with a brush in a solvent was omitted, and the other steps were the same as in Example 1 above, and charges were applied to the conductive substrate. A functionally separated laminated photoreceptor in which a generation layer and a charge transport layer are laminated was fabricated.

Then, 100 photoconductors of Examples 1 and 2 and Comparative Examples were produced as described above, and these photoconductors were transferred to a commercially available electrophotographic copying machine (EP-470 manufactured by Minolta Camera).
7) to set the initial surface potential Vo of the photoreceptor to -750.
V, development bias voltage VB was set to -500 V, reversal development was performed, black spots in the blank portion of the formed image were evaluated, and the number of defective products was measured.

As a result, in the case of Example 1, the number of defective products that occurred was 2, and in the case of Example 2, the number of defective products was 0.
In contrast, in the comparison example in which the conductive substrate was not cleaned with a brush in a solvent, the number of defective products was as large as 13.

As is clear from these results, in each example where the conductive substrate was cleaned by rubbing it with a brush in a solvent, especially
In Example 2, which used a combination of friction cleaning with a brush and ultrasonic cleaning in a solvent, there were fewer defects in the photosensitive layer than in Comparative Example in which such cleaning was not performed, and good images were obtained. In particular, black spots in white paper areas, which are a problem during reversal development, were significantly reduced.

[Effects of the Invention] As detailed above, in the method for manufacturing a photoreceptor according to the present invention, the conductive substrate for the photoreceptor is cleaned by rubbing it with a brush in a solvent, so that no mechanical process is required. In addition to oil and dust adhering to the conductive substrate prepared by

Even fine foreign matter such as dust, metal particles, and rust were sufficiently removed, and the occurrence of defects in the photosensitive layer formed on the conductive substrate was reduced.

As a result, the photoreceptor manufactured as described above has fewer defects in the photosensitive layer, does not cause image defects or poor cleaning, and has high image reliability and repeat stability. It became like this,
In particular, the occurrence of black spots on blank paper areas during reversal development was also significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of an apparatus used in an embodiment of the present invention for cleaning a conductive substrate by rubbing it with a brush in a solvent. (1)... Conductive substrate, (2)... Solvent, (4)
, (5)...Brush. Figure 1 Patent applicant: Minolta Camera Co., Ltd. Representative Patent attorney: Katsuaki Matsukawa

Claims (1)

[Claims] 1. A method for producing a photoreceptor, which comprises cleaning a conductive substrate for the photoreceptor by rubbing it with a brush in at least a solvent, and then forming a photosensitive layer on the conductive substrate.