JPS59193464A - Substrate for electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an inexpensive, small-sized and lightweight substrate ensuring favorable image characteristics and facilitating treatment after use by forming a resin layer on the surface of a paper tube, polishing the surface, and forming an electrically conductive paint film. CONSTITUTION:The surface of a paper tube is coated with resin paint to form a film, and the surface is polished and coated with electrically conductive paint. When polishing is carried out after forming the resin layer on the surface of the paper substrate as mentioned above, the fibers of the paper are fixed by the paint film, so polishing is facilitated. By forming an electrically conductive layer with the electrically conductive paint after the polishing, an electrically conductive substrate having a smooth surface free from defects can be obtd. The electrically conductive paint is preferably prepd. by dispersing electrically conductive powder such as metallic powder or carbon black in resin. The preferred volume resistivity of the electrically conductive layer is <=about 10<10>OMEGAcm. The resulting substrate is inexpensive and light in weight, improves copying characteristics, and facilitates treatment after use.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a substrate for an electrophotographic photoreceptor that is 11 m thick and lightweight.

Recently, there has been a lot of interest in the pollution-free and low cost of photoreceptors. There is particularly strong demand for small-sized copies. In such fields, it is desirable that used electrophotographic photoreceptors be easily discarded as general waste.

'Lll child copy A, /i+'? Pollution-free photosensitive layers in photosensitive bodies can be achieved by replacing selenium and cadmium sulfide with zinc oxide and organic semiconductors. with this,
The base material is also desired to be inexpensive and easy to dispose of as waste, instead of the conventional metal.

It has long been known to use paper that has been shaped to have predetermined dimensions and strength as such a substrate, but paper is an insulator and has paper fibers on its surface. , ke is standing up, so-called hosa hosa. However, even if you apply some kind of conductive treatment and use it as a base,
This roughness sometimes caused defects in the coating formation of the photosensitive layer 9 and unevenness in the copied image.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a small and lightweight substrate for an electrophotographic photoreceptor that is inexpensive, easy to remove dirt, and does not cause defects during the formation of a photosensitive layer or cause unevenness in copied images. purpose.

The substrate for an electrophotographic photoreceptor according to the present invention is characterized in that it is formed by applying a resin paint to the surface of a paper tube to form a film, polishing the surface, and then applying a conductive paint.

That is, in order to remove the roughness of the paper surface, the present invention involves forming a resin layer on the surface of the paper base, and then polishing the surface to remove the roughness of the paper and forming a conductive layer. It is characterized by The purpose of forming the conductive layer is to obtain electrical conductivity as a base. The reason why the surface is polished after forming the resin layer is that if the paper is polished without forming the resin layer, the roughness of the paper may not be removed well or may become worse. If the resin layer is formed and then polished, the paper fibers will be fixed by the coating, making polishing easier. For polishing, any method such as a wire brush, steel wool, sand vapor, grinder, cutting tool, file, etc. can be used. As the resin paint used to form the resin layer, a conductive resin paint in which conductive powder is dispersed may be used. The reason why a conductive layer is formed after polishing is that polishing causes many pinholes to occur in the previous conductive layer and reduces the smoothness of the surface. By forming the conductive layer again, it is possible to obtain a substrate with a smooth, defect-free and conductive surface.

As the conductive paint used to form the conductive layer, it is preferable to use a conductive paint with conductive powder dispersed in a resin that is rated at 1°C, rather than one made with an ionic conductive agent, which has unstable environmental stability. Conductive powders include metal powder, carbon black, tin oxide, antimono oxide, indium oxide, conductive zinc oxide, etc.Resins for dispersing them include various resins used for general paints. can be used.

By applying such a conductive paint, a paper substrate with excellent surface smoothness can be obtained. in this case,
The resin paint for the first layer and the conductive paint for the second layer may be the same or different. The volume electrical resistivity of the conductive layer coated with the conductive paint is 1010 Ωm or less, preferably about 10-5 to 1010 Ω. This differs depending on the material of the conductive paint and the addition ratio.The first layer may be a resin layer that does not contain conductive powder, but a conductive layer is preferred because it has lower resistance.Film Thickness are each 2~
It is about 50μ.

By producing the substrate in this manner, an electrophotographic photoreceptor that is inexpensive, small, lightweight, and easy to dispose of as dust can be obtained.

As the photosensitive layer, zinc oxide, organic semiconductor, etc. are used. When using an organic semiconductor, it is effective to use a functionally separated photosensitive layer in which a charge generation layer and a charge transport layer are laminated in order to increase sensitivity.

The charge generation layer is made of azo pigments such as Sudan Red, Diane Blue, and Jenas Green B, Algol Yellow,
Charges include quinone pigments such as pyrenequinone and indanthrene brilliant violet RRP, quinocyanine pigments, perylene pigments, indigo pigments such as indigo and thioindigo, bisbenzimidazole pigments such as India First Orange toner, phthalocyanine pigments such as copper phthalocyanine, and quinacridone pigments. It is formed by dispersing a generating substance in a binder resin such as polyester, polystyrene, polyvinyl butyral, polyvinylpyrrolidone, methylcellulose, polyacrylic acid esters, cellulose ester, etc. The thickness thereof is about 0.05 to 0.05 μm, preferably about 0.05 to 0.05 μm.

In addition, the charge transport layer may contain polycyclic aromatic compounds such as anthracene, pyrene, phenanthrene, coronene, etc., or indole, carbazole, oxazole, inoxazole, thiazole, imidazole, pyrazole, etc. in the main chain or side chain.
It is formed by dissolving a hole-transporting substance such as a compound having a nitrogen-containing cyclic compound such as oxadiazole, pyrazoline, thiadiazole, or triazole, or a hydrazone compound in a resin that has film-forming properties. This is because the charge transporting substance generally has a low molecular weight and has poor film-forming properties by itself. Examples of such resins include polycarbonates, polymethacrylates, polyarylates, polystyrene, polyesters, folysulfone, styrene-acrylonitrile copolymers, styrene-methyl methacrylate copolymers, and the like.

The thickness of the charge transport layer is 5 to 20 microns.

It is also effective to apply the photosensitive layer directly on the conductive layer of the substrate, or to form an undercoat layer and then apply the photosensitive layer. The undercoat layer improves the adhesion between the conductive layer and the photosensitive layer.
Improved coating properties of the photosensitive layer, protection of the substrate, improved charge injection properties from the conductive layer to the photosensitive layer, buffering against electrical breakdown of the photosensitive layer,
It is something that can be made for things such as. As the material for the undercoat layer, polyamide, polyvinyl alcohol, polyvinyl methyl ether, polyvinylpyrrolidone, methylcellulose, polyglutamic acid, casein, gelatin, starch, etc. are used.

Furthermore, since electrophotographic photoreceptors based on paper tubes may have poor dimensional accuracy and mechanical strength,
Another method, as disclosed in US Pat. No. 974, stabilizes the paper tube by fitting it into a metal cylinder inside the copying device. By doing this, even a paper tube with a thin wall can be used as the base, which is useful for making the product lighter.

Example 1 A paper tube with an inner diameter of 74 mm and an outer diameter of 80 mm was prepared.

On the other hand, a conductive paint in which carbon was dispersed (trade name: Nido-Tai) XC55, manufactured by Zazoku Kasei Co., Ltd.) was applied to a film thickness of 0 μm. After drying at 100℃, while rotating the paper tube,
The surface was polished by rubbing with 000 mesh sandpaper. As a result, the fiber waste and protrusions dA1 on the surface of the paper tube were almost completely eliminated. After that, it was cut into 300 lengths.

The same conductive paint as before was applied again to a film thickness of 5 μm and dried at 100° C. to form a substrate.

On the substrate, apply a 5% ammonia water bath solution of casein,
A casein undercoat layer having a thickness of 2 μm was formed. Next, polyamide resin (product name: Amilan CM8000, manufactured by Toshi) 0.
2 parts (by weight, same hereinafter) was dissolved in 2 parts of methanol warmed to 50°C.

To this was added 0.1 part of rose bengal and further 60 parts of n-hebutane. This is combined with electrophotographic zinc oxide powder (
50 parts (manufactured by Hakusui Chemical Co., Ltd.) were added thereto, and the mixture was stirred for 20 minutes using a homogenizer to disperse the mixture.

This was taken out through a suction port and thoroughly dried at 80°C to obtain a dye-sensitized zinc oxide coated with a polyamide resin.

To 10 parts of this zinc oxide, 4 parts of acrylic resin (trade name Niacrybase CMZ-20, manufactured by Zazoku Kasei) and 15 parts of toluene were added and mixed in a ball mill for 1 hour. Film thickness 20μ on the pull layer
The photosensitive layer was formed by coating and thoroughly drying at 100° C. to prepare an electrophotographic photoreceptor.

Attach this electrophotographic photoreceptor to a copying machine and copy!
When I took the @, the image quality was flawless.

The durability of this photoreceptor was 5,000 sheets, but the used photoreceptor could be easily incinerated.

Example 2 A paper tube with an inner diameter of 57mm and an outer diameter of 60mm was prepared, and the same conductive layer as in Example 1 was formed thereon. I also sanded the surface with +F3000 sandpaper.

Next, 100 parts of conductive-treated titanium oxide powder (trade name: Chromeno ECT-62, manufactured by Titan Kogyo), 50 parts of acrylic resin (trade name: Dianal LR6sc+, manufactured by San-i Rayon), and 70 parts of toluene. was milled in a ball mill for 10 hours to produce a conductive paint.

This conductive paint was applied onto the substrate to form a second conductive layer. The reason for using a different conductive layer is to ensure compatibility with the subsequently formed photosensitive layer.

A polyamide resin (same as in Example 1) solution was applied onto the thus treated substrate to form an undercoat layer with a thickness of 0.5 μm.

Next, 10 parts of a disazo pigment having the following structural formula, 6 parts of cellulose acetate butyrate resin (trade name: CAB-38; manufactured by Eastman Chemical Co., Ltd.) and 60 parts of cyclohexanone were dispersed for 20 hours in a sand mill apparatus using φ glass beads. . Add 100 parts of methyl ethyl ketone to this dispersion,
Five coats of dipping powder were applied on the above-mentioned undercoat layer and dried by heating at 100° C. for io minutes to form a charge generation layer with a coating weight of 0.191 ctd.

Next, a hydrazone compound having the following structural formula was added to an io-part styrene-methyl methacrylate copolymer (trade name: M
15 parts of S200 (manufactured by Seitetsu Kagaku) and 70 parts of toluene were thoroughly mixed and dissolved, and the mixture was coated on the charge generation layer. 10
It was dried with hot air at 0° C. for 1 hour to form a charge transport layer with a thickness of 16 μm, thereby preparing an electrophotographic photoreceptor.

This base is easily deformed due to the thinness of the paper, so in order to attach it to a copying machine, it is necessary to use an aluminum base with an outer diameter of 57mm, which is attached to the copying machine 5 and driven to rotate, as shown in Figure 1. An electrophotographic photoreceptor having a photosensitive layer 1a formed on a paper tube 1b was fitted into a metal cylindrical IC. By doing this, the base body is supported by the aluminum cylinder, so it does not deform, and even paper tubes with thin walls can now be used.

When I took a copy of the image, it was of good quality.

[Brief explanation of the drawing]

FIG. 1 shows a cutaway view of the vicinity of the photoreceptor seen from the top of the copying machine. 1a...Photosensitive layer, 1b...Paper tube, IC...Metal 1
Cylinder, 2...Axle, 3...Support plate, 4...Drive gear, 5...Copy machine applicant Canon Co., Ltd.

Claims (1)

[Claims] (1) After applying resin paint to the surface of the paper tube to form a film,
A substrate for an electrophotographic photoreceptor, characterized in that the surface is polished and then coated with a conductive paint.