JPH02226157A - Production of electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To decrease void defects and black hot defects and to improve image quality by subjecting the surface of a conductive base body to brush scrubbing by an org. solvent using a brush having a specific pile diameter prior to provision of a photosensitive layer on the conductive base body. CONSTITUTION:The surface of the conductive aluminum base body 1 is subjected to the brush scrubbing using an org. solvent by using the brush 31 having <=0.2mm pile diameter 311 and by injecting shower jets 21 from a shower 313. The pile diameter of the brush is preferably <=0.1mm. the materials which do not dissolve in detergents (solvents) and to not receive the other erosion are selected for the brush. For example, these materials include 'Nylon-6, -66 R ', polypropylene, etc. The void defects and black dot defects are decreased in this way and the image quality is improved.

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 utilized, the image quality problems associated with the photoreceptor base, which are extremely difficult to handle, are overlooked. That is, it is caused by deep flaws or deep contamination that are hidden under the photosensitive layer and exist 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 eliminate image defects.

Although the substrate surface is meticulously polished to a scratch-free mirror finish, contamination on the substrate surface, which is a frequent deep-seated cause of 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. 1 is a mirror-finished base, 2
3 is a cleaning agent reservoir, and 32 is an ultrasonic generator as a cleaning means. The substrate 1 is moved up and down the cleaning agent reservoir during cleaning.

Further, high-pressure jet cleaning is performed by spraying the cleaning agent jet 22 from the jet nozzle 33 onto the vertically moving substrate 1, as shown in FIG. Jet pressure is 30-100kg/
cm2. A cleaning system usually preceded by an ultrasonic bath and followed by a steam bath is applied.

The cleaning agents for both cleanings include halogen-based organic solvents; trichlorethylene, perchloroethylene, 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 and image defects cannot be sufficiently prevented.

[Purpose of the invention]

In view of the above-mentioned circumstances, it is an object of the present invention to eliminate contaminants that cannot be removed by external follow-up treatments and that are located beneath the photosensitive layer and on the surface of the photoreceptor substrate and that cause image quality degradation. 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, in the production of an electrophotographic photoreceptor,
By a method for producing an electrophotographic photoreceptor, which comprises, prior to providing a photosensitive layer on the conductive substrate, subjecting the surface of the conductive substrate to brush scrubbing with an organic solvent using a brush with a pile diameter of 0.2 mm or less. achieved.

In the aspect of the present invention, it is more preferable that the pile diameter of the brush used for brush scrubbing with the organic solvent is 0.1 mm or less.

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, l is a base, and 31 is a columnar brush having piles 311 radially planted on a brush shaft 312.

Reference numeral 313 denotes a shower that guides the cleaning agent from the cleaning agent reservoir 2 and sprays the 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.

The diameter of the pile of the brush is 0.2 mm or less,
Further, it is preferably 0.1 mm or less, and the material is selected from a material that is not susceptible to dissolution or other corrosion in cleaning agents (solvents). For example, nylon-6, -66, and polypropylene are common examples and can also be used in the present invention.

Furthermore, the length of the bristles of the brush is preferably 10 to 30n+m.

Further, the direction in which the pile is planted is not limited to the direction perpendicular to the axis, and the tip may form a loop.

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

The brush shaft is also made of solvent-resistant material, such as stainless steel.

The cleaning agent is preferably an organic solvent, such as halogenated hydrocarbon trichloroethylene, 1,1,11-lychloroethane, methylene chloride, perchlorethylene, chloroform, carbon tetrachloride, fluorocarbon, and mixed solvents thereof, alcohol-based methanol. , ethanol, isopropyl alcohol, or acetone, benzene, toluene, xylene, etc. are used, but they have 1.1. i-trichloroethane is preferred.

The brush scribe cleaning of the present invention can also be used in combination with the ultrasonic cleaning system described above.

〔Example〕

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

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

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

Mouth, cleaning method a, ultrasonic cleaning solvent; 1,1. il-lichloroethane ultrasonic wave; frequency 28KHz, output 600W.

Output density 0.6w/cm2 Immersion; Rinse cleaning steam; Pre-finish cleaning by condensation of solvent vapor; C0 solvent brush cleaning solvent same as a, 1,1.1-trichloroethane brush: (Material/dimensions) Nylon brush, pile Q, 2mm.

Bristles 30mm (rotation speed) brush ioorpm, base 3Orpm (shower liquid volume) 412/mlnb, high pressure jet cleaning solvent; 1.1. i Trichloroethane jet; 8
0 kg/cm" (5012/m1n) Ultrasonic wave; Coating the same halo photosensitive layer as in a. The following organic photosensitive layer was coated on the cleaned aluminum substrate as shown in Figure 2.

2. Evaluation image evaluation machine is laser beam printer rLips-10
4 (manufactured by Konica Corporation) 1. %Ta. (Table-4)a,
Visual observation of the substrate surface, confirmation of normal developed image quality - Change in copy number and image quality - Ultrasonic cleaning products and high pressure jet cleaning products had white defects on solid black images.

- Especially for ultrasonic cleaned products, as the number of copies increases,
White defects increased.

・Products cleaned with solvent brushes did not have white defects, and the image quality was good even when the number of copies increased.

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

Example-2 Brush with pile diameter of 0-2 mm or less and pile diameter of 0.2
The effect on the reversal developed image when using a brush exceeding 1 mm was compared.

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 term conditions of Example-1) b. Brush material and dimensions The presence or absence of occurrence and image quality were examined.

(Table 6) The evaluation machine used was a Lips-IQ r reversal developing modified tank.

C. Preparation of photoreceptor The following organic photosensitive layer was coated on the aluminum substrate which had been cleaned.

E, Evaluation & Observation of the substrate surface after double scrub cleaning (Note) O
Level of 0 to 2 black spots on A4 paper × Many black spots occur on A4 paper When using a brush with a pile diameter of 0.2 mm or less, there are almost no scratches on the surface of the aluminium substrate. An undercoat layer that blocks charge injection from the substrate was coated on the substrate surface with a uniform thickness.

As a result, black spot defects caused by charge injection from minute parts of the substrate rarely occurred.

Particularly when a brush with a pile diameter of 0.1 mm or less was used, no black spot defects occurred at all.

・When using a 0.3 mm brush with a pile diameter exceeding 0.2 mm, countless scratches with 0.1 to 0.2 μm irregularities were generated on the aluminum substrate surface, so the undercoat layer with the above-mentioned function was not uniform. The film was not coated with a sufficient film thickness. As a result, charges were injected from the substrate in the thinner portions of the film, and black spot defects were generated over the entire surface of the white paper at a rate of 10 to 20 pieces/dm''.

If a brush with a pile diameter of 0.2 mm or less is used, almost no scratches will be observed on the surface of the substrate.

Therefore, the undercoat layer is coated with a uniform thickness, and almost no black spot defects occur on the blank image during reversal development.

〔effect〕

The effects of brush cleaning using an organic solvent as a cleaning medium and a brush with a pile of 0.2 mm or less are as follows.

■Cleanability is significantly improved.

■Flaws rarely occur on the substrate surface.

As a result of (1) and (2), the white spot defect in normal development and the dark spot defect in reverse development were significantly reduced, and the image quality was significantly improved.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a brush scrub according to the present invention, and FIG. 2 is a partial sectional view of an example photoreceptor. Figure 3 shows ultrasonic cleaning.
FIG. 4 is an explanatory diagram of high-pressure jet cleaning. ■...Substrate, 2...Cleaning side temperature, 21.
...Shower jet, 31...Column brush, 311...
・Brush pile.

Claims (1)

[Claims] In the production of electrophotographic photoreceptors, prior to providing a photosensitive layer on a conductive substrate, a pile diameter of 0.2 is applied to the surface of the conductive substrate.
1. A method for producing an electrophotographic photoreceptor, which comprises performing brush scrub cleaning with an organic solvent using a brush of mm or less.