JPS62174770A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive body which is stable to moisture and has high sensitivity and high durability by providing a prescribed moisture resistant protective layer on a photoconductive layer consisting of inorg. conductive powder and glass binder on a conductive base. CONSTITUTION:The photosensitive body is constituted by providing the moisture resistant protective layer 3 on the photoconductive layer 2 consisting of the inorg. conductive powder and glass binder on the conductive base 1. The moisture resistant protective layer 3 is any of films essentially consisting of silicon- carbon, silicon-nitrogen and boron-nitrogen. The protective layer 3 is formed by plasma CVD or photo CVD to 0.05-5mu thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a photoreceptor used in dry and wet copying machines, particularly a photoreceptor made of an inorganic photoconductive powder and a glass binder, and is used for recording in copying machines, printers, etc. This can be applied to engines.

PRIOR ART A patent for an inorganic photoreceptor using a glass binder is disclosed in Colesyn's USP 31519B2, and this photoreceptor has many times longer durability and superior sensitivity than conventional selenium photoreceptors. is known, but it has not been put into practical use because it lacks moisture resistance.

In order to improve this drawback, Japanese Patent Publication No. 45-24919 (
In the method for improving the humidity stability and abrasion resistance of pyrograph glass binding plates), has it been proposed to improve the moisture resistance by diffusing selenium into the surface layer? This proposal has also not been put to practical use.

In recent years, the A-3I photoconductor has attracted attention for its high sensitivity and high durability, but because the thickness of the photosensitive layer is around 20μ, the potential contrast is weak, and special development technology is required to obtain the desired image density. need.

By the way, the reason why the photosensitive layer cannot be made thicker with this a-3i exposure is that a) if the thickness is made more than 40μ, the photosensitive layer becomes easy to break;
In addition, film quality characteristics deteriorate.

b) Forming a thick photosensitive layer requires manufacturing time and increases cost.

Purpose The present invention solves the above-mentioned problems of the prior art. b) providing a highly sensitive, highly durable photoreceptor that is developable with conventional development techniques at a lower cost than the a-3i photoreceptor; c) for use in dry and wet copiers. The purpose is to provide a photoreceptor that can

Structure The structure of the present invention to achieve the above object is to provide an electrophotographic photoreceptor having a moisture-resistant protective layer on a photoconductive layer made of an inorganic photoconductive powder and a glass binder on a conductive support. It is.

To specifically explain the above inorganic photoconductive powder, calcium strontium sulfide, zinc sulfide, zinc oxide, zinc arsenide, cadmium sulfide, arsenic sulfide, -lead oxide, and selenide are shown in Japanese Patent Publication No. 45-24919. These include gallium, indium sulfide, arsenic selenide, mercuric oxide, duplex titanium, and zinc titanate.

The moisture-resistant protective layer is a film mainly composed of silicon-carbon, silicon-nitrogen, or boron-nitrogen. For example, a film mainly composed of boron-nitrogen has the following structure.

general formula %formula% However, 0<x<1, O≦y<0.5 X represents the third component.

That is, in some cases it is substantially composed of nitrogen and poron (in the case where y=O), and in some cases it may contain a third component, and the third component X includes hydrogen, chlorine, fluorine, etc.

Hydrogen, chlorine, fluorine, etc. act as terminators for dumping bonds in the amorphous poron-nitrogen film, or -coordination hydrogen, halogen, etc. increase the flexibility of the structure and form a high-quality film with low defect density. can.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 Composition of glass binder frit Surrounding acid 20wt% calcium oxide 13wt% zinc oxide
21W1% anhydrous sand 28wt
% Sodium Orthosilicate 18wt% Raw material blend with the above composition 200! Put II into the aluminum pot, 11
The mixture was heated to 00° C. for 3 hours to melt.

This was poured into deionized water to make a glass frit.

50 g of this glass frit was placed in a well-washed 9 cm diameter ball mill manufactured by JTA, and 30 ml of deionized water was added thereto, followed by wet milling at 86 rpm for 5 hours.

CdS powder (manufactured by GE, No.

118-8) 12c+r was added and mixed for 5 minutes using a homomixer to disperse the powder, which was spray coated onto two well-washed low carbon steel plates with a thickness of 15 m and 0.0 m to form a photoconductive layer. .

The carbon steel plate provided with this coating layer was placed in an electric furnace at a temperature of 550°C, fired for 5 minutes, and then slowly cooled to obtain a photoreceptor having a photosensitive layer with a thickness of about 10 μm.

These were designated as photoreceptor A and photoreceptor B.

Photoreceptor A was set in a plasma CVD apparatus, and a film mainly composed of 5i-C was formed with a thickness of 0.3 μm under the following silicon-carbon film (SRC film) formation conditions, and this was applied to photoreceptor C. And so.

5i-CPU formation conditions SiH4 concentration of 10% in hydrogen 3i1-14 CH4 concentration of 10% in hydrogen of CH4 Pressure 3 torr Total flow 10105sc Radio frequency input power (RF Power) 35 watts (13
, 568H2) Photoreceptor temperature: 250°C S; An image forming experiment was conducted using Photoreceptor C having a -C film and Photoreceptor B having no 5i-C film.

The results of this experiment showed that when photoconductors B and C were charged by applying 17kV to a corona charger, they had a surface potential of about 700V, which is a potential contrast that can be developed sufficiently by magnetic brush development after exposure. Met. However, in the case of photoreceptor B, in an atmosphere of 30° C. and 50% RH, development was observed in which the image became blurred. On the other hand, photoreceptor C did not exhibit image blurring under the above conditions, and even under 30'C190%RH.

Example 2 Silicon-based film was used instead of the 5i-C film of Example 1.
A film mainly composed of nitrogen (Si-N>) was formed on the surface of a glass binder photoconductor, and an image forming experiment similar to that in Example 1 was conducted.

5i-N film formation conditions 3i1-14 5iH4NHI with a concentration of 10% in hydrogen
N H3 pressure at 10% concentration in hydrogen
3tOrr flow rate
150CCM high frequency input power 200watts (1
3,56Htlz) Photoreceptor temperature 25
The results of the 0°C image formation test were s+-N as in Example 1.
A film based on 3.
Even under the conditions of 0''C and 90% RH, a good image was obtained without blurring.

Example 3 An image forming experiment similar to that in Example 1 was conducted by forming a film mainly composed of poron-nitrogen (B-N>) in place of the film mainly composed of 5i-C in Example 1 under the following conditions.

B-N film formation conditions B2 H6 concentration in hydrogen 0.3% 82 HGNH3 concentration in hydrogen 2% NHI Pressure 1 torr Total flow rate
150CCH high frequency input power 2
00watts (13,56MHz) Photoreceptor temperature
The results of the 250°C image formation are shown in Example 2.
Similarly, in the case of the one having a moisture-resistant protective layer which is a BN film, a good image was obtained without blurring even under the conditions of 30'C190%RH.

Example 4 The following photoconductive layer forming solution was prepared using a glass frit manufactured by Nippon Ferro Co., Ltd. (No, At-80) in place of the glass frit used in Example 1.

Composition of photoconductive layer forming liquid Glass frit (AL-80) 50 gr floating agent (AL-30J) 6 gr deionized water 19 ml Cadmium sulfide powder (GE-118-8-2) 33.3 gr This liquid was thoroughly degreased. The mixture was cast onto an aluminum plate with a thickness of 0.5 mm, air-dried, and then gradually placed in an electric furnace maintained at 538° C.±4° C., fired for 6 minutes, and then slowly cooled before being taken out from the furnace.

The thus produced photoreceptor was heated to a temperature of approximately 70% in a 7% aqueous solution of Granda Cleaner M
After immersing in a solution at ℃ for 10 minutes, thoroughly washing with water and drying,
It was like a photoreceptor. The film thickness of the photoconductive layer of this photoreceptor is 61μ
Met.

51-C of Example 1 was added to the photoreceptor having the same structure as the above photoreceptor.
Photoreceptors (E-L) were made with 5R-C films of various thicknesses formed under the same conditions as the film formation conditions, but only for different times, and image tests were conducted on these in environments with different temperature and humidity. .

The results are shown in Table 1 below.

Table 1 Note 1, Q: No image blur, △: Some images are blurred, The results show that the thickness of the protective film is preferably in the range of 0.05 to 5 μm.

Similar results were obtained when the same test was conducted on a protective film mainly composed of 5i-N system and a protective film mainly composed of BN system.

Further, in each of the above Examples, the protective film was formed by plasma CVD, but similar results were obtained by photo-CVD.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, the stability of an electrophotographic photoreceptor in which a fine photoconductive powder is mixed in a non-photoconductive insulating glass enamel binder in a high humidity environment is improved. can do.

[Brief explanation of drawings]

The drawing is an explanatory view of the structure of the electrophotographic photoreceptor of the present invention. DESCRIPTION OF SYMBOLS 1... Conductive support body, 2... Photoconductive layer, 3... Moisture-resistant protective layer.

Claims (5)

[Claims] (1) An electrophotographic photoreceptor having a moisture-resistant protective layer on a photoconductive layer consisting of an inorganic photoconductive powder and a glass binder on a conductive support. (2) a film in which the moisture-resistant protective layer is mainly composed of silicon-carbon;
Claim (1) which is either a film mainly composed of silicon-nitrogen or a film mainly composed of boron-nitrogen.
The photoreceptor described in section. (3) The photoreceptor according to claim (2), wherein the moisture-resistant protective layer has a thickness of 0.05 to 5 μm. (4) the moisture-resistant protective layer is formed by plasma CVD;
A photoreceptor according to any one of claims (1) to (3). (5) The photoreceptor according to any one of claims (1) to (3), wherein the moisture-resistant protective layer is formed by photo-CVD.