JPH02226158A - Production of electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve durability and washing capacity by using fluoroplastic to form the piles of a brush to be used for brush scrubbing by an org. solvent. CONSTITUTION:The surface of a conductive base body is subjected to brush scrubbing using the org. solvent prior to provision of a photosensitive layer on the conductive base body. The rotation of the base body 1 and the brush 31 is controlled by adjusting the rotating speed or the direction of rotation in such a manner that the brush piles 311 rub the base body 1 surface. The materials which do not dissolve in detergents, do not receive the other erasion, do not leave contaminating films on the base body surface, do not generate the consumption and chipping of the brush piles themselves and further do not apply the flaws to exert adverse influence on the electrophotographic characteristics on the base body surface by scribing are selected as the material of the piles 311 of the brush 31. The fluoroplastic is used for the above- mentioned material. The durability and washing capacity are improved in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the manufacture of electrophotographic photoreceptors, and more particularly to cleaning of photoreceptor substrates.

[Prior art]

Photoreceptors used in electrophotography consist of a metal cylindrical (mainly aluminum) substrate or a substrate with a conductive surface layer, and a photoconductive layer such as selenium, or an organic charge-generating substance and charge-transporting substance. A photosensitive layer is provided as a single layer or laminated as separate layers, and various auxiliary layers such as a protective layer and an intermediate layer are added as necessary.

As electrophotographic copying becomes widespread and becomes an important means of information processing, high image quality without failure is required. The materials are constantly improved and improved.

However, even if these techniques for surrounding the photoreceptor are used, the image quality problems associated with the photoreceptor substrate, which are extremely difficult to handle, are overlooked. That is, it is caused by deep contamination or deep contamination that is hidden under the photosensitive layer and exists on the surface of the photoreceptor substrate, such as small white spot failures that occur in solid black image areas.

That is, if there are flaws or contamination on the surface of the substrate, the ability to block charge injection from the substrate is impaired, resulting in image defects and a significant deterioration in image quality. As a countermeasure against this problem, measures such as providing a conductive barrier layer between the substrate surface and the photosensitive layer to suppress charge injection are taken, but it is difficult to erase image defects.

Although the surface of the substrate is meticulously polished to a mirror-like finish without any scratches, contamination on the surface of the substrate, which occurs in deep spaces that often cause image defects, is conventionally removed by ultrasonic cleaning or high-pressure jet cleaning.

Ultrasonic cleaning is performed as a set of a hot bath, an ultrasonic irradiation bath, a cold bath, and a steam bath, and ultrasonic irradiation is added if necessary.

The outline is shown in Figure 3. l is a mirror-finished base, 2
32 is a cleaning side temperature, and 32 is an ultrasonic generator as a cleaning means. The substrate 1 is heated up and down on the cleaning side during cleaning.

Further, high-pressure jet cleaning is performed by spraying a cleaning agent jet 22 from a jet nozzle 33 onto the vertically moving substrate 1, as shown in FIG. Jet pressure is 30-100kg/
cm'. It is usually applied in a cleaning system preceded by an ultrasonic bath and followed by a steam bath.

The cleaning agent for the re-cleaning includes halogen-based organic solvents; trichlorethylene, perchlorethylene, methylene chloride,
1,1.1-trichloroethane, chloroform, carbon tetrachloride, fluorocarbon or benzene, toluene, isopropyl alcohol, ethanol, methanol, acetone, xylene, etc. are used.

However, even with these powerful cleaning methods, complete cleaning is difficult.

[Purpose of the invention]

In view of the above-mentioned circumstances, an object of the present invention is to eliminate contamination that cannot be removed by external follow-up treatment and is located under the photosensitive layer and on the surface of the photoreceptor substrate and causes poor image quality. It is an object of the present invention to provide a photoreceptor that does not cause image defects.

[Structure and effects of the invention]

The object of the present invention is to provide a brush used for brush scrubbing with an organic solvent in a method for manufacturing an electrophotographic photoreceptor in which the surface of a conductive substrate is brush scrubbed with an organic solvent before a photosensitive layer is provided on the conductive substrate. This is achieved by a method for manufacturing an electrophotographic photoreceptor, characterized in that the pile is made of a fluorine-based resin.

Next, the present invention will be explained using figures.

FIG. 1(a) shows an embodiment of the present invention as a plan view, and FIG. 1(b) shows a side view as seen from the direction of the rotation axis of a rotating base body.

In the figure, ■ is a base, and 31 is a columnar brush having piles 311 radially planted on a brush shaft 312.

A shower 313 introduces a cleaning agent from the cleaning side temperature 2 and sprays a shower jet 21 onto the rotating base 1.

The rotation of the base and the brush is controlled by adjusting the rotation speed or the direction of rotation so that the brush pile rubs against the base surface.

In the present invention, the brush pile is made of a material that does not dissolve or undergo other corrosion in cleaning agents (solvents), does not leave a contaminated film on the surface of the substrate, and does not cause wear and tear of the brush pile itself; Furthermore, a material that does not cause any flaws on the substrate surface that would adversely affect the electrophotographic properties by scribing is selected. It may form a loop.

Furthermore, when the tip is a bleed, it may be rounded.

The pile diameter is preferably 0.2 mm or less. Moreover, the length of the hair is preferably 10+++m to 30mm.

It is preferable that the shaft of the brush is solvent resistant, for example, fluorine resin, stainless steel, etc. are selected.

The cleaning agent is preferably an organic solvent, such as halogenated hydrocarbon trichlorethylene, 1.1,1-1-! J chloroethane, methylene chloride, perchlorethylene, chloroform, carbon tetrachloride, fluorocarbon, and mixed solvents thereof, alcoholic methanol, ethanol, isopropyl alcohol, and others such as acetone, benzene, toluene, and xylene are used.

The brush scribe cleaning of the present invention is most effective when applied between the ultrasonic irradiation and the cold bath of the ultrasonic cleaning system described above.

〔Example〕

Next, the effects of the present invention will be illustrated by examples.

Example-1 Comparison of ultrasonic cleaning, high pressure jet cleaning and solvent brush cleaning.

A. Object to be cleaned After the surface of the aluminum substrate was polished to a mirror finish, it was left for one month and became difficult to clean.

Cleaning method a, ultrasonic cleaning solvent; 1.1.14 Lichloroethane ultrasonic wave; frequency 28 KHz, output 600 W.

Power density 0.6 w/cm” Immersion; rinse cleaning steam; final cleaning by condensation of solvent vapor, high pressure jet cleaning solvent; 1.1.1-trichloroethane jet;
80kg/cm'' (50ff/m1n) Ultrasound: Same as Table 2. The following organic photosensitive layer was coated as shown in Table 2.

C9 solvent brush cleaning solvent; 1,1.14 Lichloroethane brush; (Material/Dimensions) P, FA brush, pile diameter 0
．． 2mm.

Hair length 30mm (rotation speed) brush 1100rp, base 30rpm (shower liquid volume) 4ff/min Ultrasound; same as a, evaluation image evaluation machine is laser beam printer rLips-1O
” (manufactured by Konica Corporation) was used. (Table 4) a. Visual observation of the substrate surface. Confirmation of normal developed image quality - Change in copy number and image quality. A white spot defect occurred on the image.

As shown in FIG. 2 on the cleaned aluminum substrate, in particular,
Ultrasonic cleaned products increase the number of copies. , the number of white spots increased.

・Products cleaned with solvent brushes were in good condition with no white spots.

E, summary: Solvent brush cleaning is better than ultrasonic cleaning and high-pressure jet cleaning.
It has cleaning ability and can obtain good image quality.

Example 2 Comparison of a fluororesin brush and a polypropylene brush in solvent brush cleaning.

B. Object to be cleaned The aluminum substrate surface was polished to a mirror finish and then left for a month, making it difficult to clean.

Cleaning method a. Process Solvent brush cleaning (Low C condition of Example-1) b. Brush material and dimensions Material Pile diameter Pile length P F A
O, 2mm 30mm polypropylene
0.2 mm 30 mm C9 Number of cleanings: 5000 in a row C. Application of photosensitive layer The same photosensitive layer as in Example 1 was applied to the washed aluminum substrate.

2. Evaluation (Table 5) a. Image evaluation of observation of the substrate surface after cleaning the brushes The occurrence of white spot defects on solid black images during regular development was observed as the number of brushes cleaned increased.

- Scratches on the surface of the substrate When cleaning with a PFA brush, no scratches were found on the surface of the substrate, but when cleaning with a polypropylene brush, scratches were found on the entire surface of the substrate.

- Image quality The PFA brush maintained good cleaning performance from the initial stage to the 5,000th cleaning, and no image defects were caused by the cleaning substrate.

For the polypropylene brushes, drums with image defects appeared after 1000 brushes were washed, and the cleaning effect rapidly decreased as the number of brushes washed increased.

This is because as the number of brushes being washed increases, the tips of the brush bristles crack and become plastically deformed, resulting in a decrease in the washing and cleaning ability.

E. Summary It was confirmed that the plan made of fluorine-based resin is more durable than the brush made of polypropylene, and has a good cleaning ability up to at least 5000 brushes.

Example-3 The same cleaning as in Example-2 was carried out using an rPFA brush pile diameter of 0.
When the test was carried out using a brush with a brush size of 1 mm and a bristle length of 30 mmJ, the same effect as the rPFA brush of Example 2, a brush with a pile diameter of 0.2 mm and a bristle length of 30 mmJ was obtained.

Example 4 The same cleaning as in Example 2 was carried out using an rPTFE brush with a pile diameter of 0.2 mm and a bristle length of 30 mm.Example. -2 rPFA brush with a pile diameter of 0.2 mm and bristles of 30 mm1 had similar effects.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of a brush scrub according to the present invention, and FIG. 2 is a partially sectional view of an example photoreceptor. Figure 3 shows ultrasonic cleaning.
FIG. 4 is an explanatory diagram of high-pressure jet cleaning. l...Substrate, 2...Cleaning side temperature, 21
... Shower jet, 31 ... Columnar brush, 31
1... Brush pile.

Claims (1)

[Claims] In a method for producing an electrophotographic photoreceptor in which the surface of the conductive substrate is subjected to brush scrubbing with an organic solvent before forming a photosensitive layer on the conductive substrate, the pile of brushes used for the brush scrubbing with the organic solvent is made of fluorine-based resin. A method for manufacturing an electrophotographic photoreceptor, characterized in that: