JPS61156134A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive material causing small dark attenuation and having low residual potential by simultaneously adding arsenic and oxygen to selenium. CONSTITUTION:To selenium are added 10-10,000ppm arsenic and 1-1,000ppm oxygen. Oxygen is added so as to reduce the residual potential, bud >1,000ppm oxygen is liable to cause bumping during vapor deposition and makes a vapor- deposited film defective. Arsenic is added according to the amount of oxygen added so as to prevent principally deterioration in the dark attenuation characteristics. By the synergism of 1-1,000ppm oxygen and 10-10,000ppm arsenic the residual potential can be reduced while satisfactory dark attenuation characteristics are maintained. Oxygen is added in the form of SeO2 of a mother alloy of Se-SeO2 or by bubbling.

Description

[Detailed Description of the Invention] As the selenium used in the present invention, it seems possible to use conventional grade selenium of 4N to 5N, but recently a higher purity product (6N) has also been produced. ,
In the present invention, it is preferable to use such a high purity (6N) material.

High-purity selenium has fewer impurity traps and a lower residual potential. For example, conventional selenium exhibits a residual potential of 47V, whereas high-purity selenium with 6N purity has a residual potential of 2.
It is 8V.

In the present invention, 1 to 1000 ppm of oxygen is added for the purpose of reducing residual potential. The amount of oxygen added depends on the purity of the selenium, but is selected to give a residual potential of about 10 μm. Even if oxygen is added in excess of 1000 ppm, the effect is substantially saturated. Furthermore, if oxygen is added in excess of 1000 ppm, bumping is likely to occur during vapor deposition, causing defects in the vapor deposited film.

Arsenic is added depending on the oxygen t mainly to prevent deterioration of dark decay characteristics, and is added in an amount of 10 to 10.
000 ppm. Oxygen and arsenic in the above range cooperate to reduce the residual potential while maintaining good dark decay characteristics. The preferred range is arsenic 100-10. OOOppm and oxygen 10~t, 0
00 ppm.

Oxygen is added in the form of a master alloy made from 5ea2 or Se-5eOz or by oxygen bubbling;
This poses no problem in handling compared to the case of adding chlorine. Arsenic is pure arsenic, Se-As alloy or AS
It is added in the form of 2 Se s .

An electrophotographic photoreceptor is obtained by vacuum evaporating the thus obtained selenium-arsenic-oxygen photosensitive material as a deposition source onto a drum conductive substrate.

As mentioned above, single-layer type and laminated type photoreceptors have been put into practical use. In the latter case, the photosensitive material of the present invention is used to form a photosensitive layer.

The conditions for vacuum deposition are not limited to %, and commonly used conditions are sufficient. Vapor deposition source temperature 250-35
0℃, substrate temperature 55~75℃, degree of vacuum IO-5~10
-' Torr and deposition time of 60 to 131) minutes by selecting appropriate conditions. As a substrate,
Metals such as aluminum and steel, metallized paper, or plastics are used.

Effects of the Invention By simultaneously adding arsenic and oxygen to selenium, effects at least comparable to the simultaneous addition of arsenic and chlorine can be obtained. Addition of oxygen is easier to handle than addition of chlorine, and has great advantages in terms of production technology.

Example To prepare a Se-As-0 alloy, high-purity selenium (6N), arsenic (6N), and Nippon Sogyo Co., Ltd. were used. lf
A predetermined amount of selenium fluoride (4N) was weighed out and vacuum-sealed into a Pyrex ampoule with a length of 30 heel outer diameter x 22Dllll. This was melted at 550° C. for 2 hours in a swinging heating furnace while swinging at a rate of 10 times/minute. Thereafter, the ampoule was crushed to remove the alloy.

The alloy produced in this way was heated to 55cm×
It was vacuum deposited on a No. 55-finished aluminum substrate. The deposition conditions are as follows.

Evaporation source temperature: 300° C. Substrate temperature: 70° C. Degree of vacuum: 2×10 Torr Vapor deposition time: The thickness of the deposited film formed on the aluminum substrate over 90 minutes was approximately 50 μm.

The electrophotographic properties of the alloy vapor-deposited film thus obtained were measured using an electrostatic testing device. The measurement conditions are as follows.

Corona discharge voltage: 5 kV Light irradiation time: 2 seconds Light Illuminance: 3000 lux Repetition number: 200 times As is kept constant at 2000 ppm, and the results of adding oxygen from 1 ppm to 1.000 ppm are shown in the drawing.

In Figure 1, the curve ■ is the initial surface potential ■. and the curve ■ is the potential V after 10 seconds of being kept in the dark state.

It is. Figure 2 shows the residual potential. From the drawings, it can be seen that the residual potential can be reduced without deteriorating the dark decay characteristics.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the relationship between the amount of oxygen added and the surface potential, assuming that arsenic is constant at 2000 ppm, and FIG. 2 is a graph showing the relationship between the amount of oxygen added and the residual potential. Residue list t (V) Surface 1v - Squid = (V)

Claims (1)

[Claims] 1) Selenium with 10 to 10,000 ppm arsenic and 1 to 1
A photosensitive material for electrophotography, characterized in that ,000 ppm of oxygen is added. 2) Selenium with 10-10,000 ppm arsenic and 1-1
An electrophotographic photoreceptor comprising a thin film photosensitive layer formed on a conductive substrate using a thin film forming material to which ,000 ppm of oxygen is added. 3) In the laminated electrophotographic photoreceptor, selenium contains 10 to 1
Electrophotography in which a thin film photosensitive layer is formed on a conductive substrate using a thin film forming material to which 0,000 ppm arsenic and 1 to 1,000 ppm oxygen is added, and one or more layers are provided above or below a pure selenium or other photosensitive layer. Photoreceptor.