JPS62294253A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To uniformize the tellurium concn. of a photosensitive layer and to stabilize the characteristics of a photosensitive body by adding tin to a raw material of a selenium-tellurium alloy for evaporation and subjecting the material to vapor deposition, thereby forming the photosensitive layer. CONSTITUTION:A carrier transfer layer 2 is formed on a substrate 1 consisting of Al, etc., and a carrier generating layer 3 is formed thereon, by the vapor deposition of the selenium-tellurium alloy, by which the electrophotographic sensitive body is obtd. The vapor deposition is executed in this stage by adding the tin to the selenium-tellurium alloy. For example, the tin is added at about 1,000ppm to said alloy in the case of the vapor deposition of the carrier transfer layer 2 and the tin is added thereto at about 3,000ppm in the case of the vapor deposition of the carrier generating layer 3. The fractional distillation of the tellurium is suppressed and the concn. distribution of the tellurium in the carrier transfer layer 2 and the carrier generating layer 3 is uniformized by the addition of the tin to the above-mentioned alloy. Since the vapor deposition is executed by adding the tin to the selenium-tellurium alloy, the variance in the sensitivity and dark attenuation characteristic of the photosensitive is decreased and the image density is stabilized.

Description

[Detailed description of the invention]

3. Detailed description of the invention

[Technical field to which the invention pertains]

The present invention relates to an electrophotographic character having a selenium-tellurium photosensitive layer deposited using a selenium-tellurium alloy as a raw material.

[Prior art and its problems]

The selenium-tellurium based photosensitive layer is usually formed by evaporating a selenium-tellurium alloy in a vacuum of 10-' torr or less and depositing it on the surface of a conductive substrate made of M or the like. The selenium-tellurium alloy used as the evaporation raw material contains less than 50% Te.
In the case of a functionally separated type, the photosensitive layer to be formed is generally composed of 100%≧Se≧90%, 10≧Te on a substrate 1 such as M, as shown in FIG. ≧O%
2.90% carrier transport layer with a thickness of 40 to 70%, deposited from pure selenium or selenium-tellurium alloy as raw material.
Selenium with ≧Ss≧70%, 309A≧Te≧10%
It has a carrier generation N3 with a thickness of 5 to 1 ion, which is deposited using tellurium alloy as a raw material. The photoreceptor shown in FIG. 4 has its surface coated with a coating 1114 to improve its rigidity, and is used in high-speed PPC copying machines or laser printers. The carrier transport N2 on the substrate l has a thickness of 40 to 70 Pa, and the main composition of the evaporation raw material is 100%≧Ss≧90% and 10%≧Te≧0%. The carrier generation N3 has a thickness of 1 to 5μ, and the composition of the evaporation raw material is 90%≧38≧50%, 50%↑e≧10
% is the mainstream. The thickness of the protective layer 4 is 107111 or less, and the composition of the evaporation raw material is 100%>Se≧95%, 5%≧Te≧
O% is the mainstream. Some contain less than 5% A instead of Te.
Raw materials containing s may also be used. The selenium-tellurium alloy used to obtain these photosensitive layers has a large composition of selenium, for example, 10-'t
The saturated vapor pressure temperature of selenium when vapor deposited with orr is 417
K, tellurium is significantly different from 527, therefore, selenium and tellurium undergo fractional distillation in the evaporation source, and the composition of selenium and tellurium in the resulting photosensitive layer loses uniformity, and the tellurium increases as it moves away from the substrate. Concentration increases. Figure 2 shows the tellurium concentration distribution curve in the film thickness direction of the photosensitive layer having the structure shown in Figure 3 obtained by EPMA (electron probe microanalysis), which shows that the tellurium concentration in the photosensitive layer is not uniform throughout the entire stone. It shows. Moreover, this Te concentration distribution varies depending on the material loft of the selenium-tellurium alloy, the deposition conditions, etc., and has poor reproducibility. This particularly has a negative effect on the sensitivity characteristics and dark decay characteristics of the photoreceptor.

[Purpose of the invention]

The present invention solves the above-mentioned problems, suppresses fractional distillation of tellurium, forms a photosensitive layer with a uniform tellurium concentration distribution, has stable photoreceptor characteristics, and produces stable copy images for electrophotography. The purpose is to provide a photoreceptor.

[Key points of the invention]

The present invention achieves the above-mentioned limitations by forming a selenium-tellurium based photosensitive layer by vapor deposition using a selenium-tellurium alloy added with tin as an evaporation raw material.

[Embodiments of the invention]

FIG. 1 shows a tellurium concentration distribution curve of a photosensitive layer obtained according to an embodiment of the present invention. Carrier transportation JK for raw materials! A photoreceptor with the structure shown in Fig. 3 was prepared by adding 1000 ρpi of tin in the case of 2-vapor deposition and 3000 ppm of soot in the case of carrier-generating 1i3 evaporation. The concentration width d of the transport layer is reduced to about 1/3,
It can be seen that the uniformity of the tellurium concentration distribution has improved. As a result, the characteristics of the photoreceptor are also improved. Figure 5 shows the carrier transport layer, Figure 6 shows the effect on dark decay when soot is added only to the evaporation raw material in the carrier generation layer, Figure 7 shows the carrier transport layer, and Figure 8 shows the evaporation raw material in the carrier generation layer. The effect of adding soot on the optical attenuation is shown, and the attenuation decreases with the addition of tin. The number of samples is [0] for each, and the dotted line in the figure indicates the standard value. Tables 1 and 2 show the standard dark attenuation value of 80 V or less and the standard value of optical attenuation of 250 to 550 V when tin is added to the carrier generation layer (CGL) and carrier transport layer (CTL) raw materials.
The interaction with each is shown. Table 1 Dark attenuation (V) Standard 80V
From the results of comparison with the standard values below, taking into consideration that it is desirable that the dark attenuation is small and the light attenuation is large, the amount of tin added to the carrier transport layer of the functionally separated photoreceptor is 10
It is particularly effective that the amount of tin added to the carrier generation layer is in the range of 1000 to 5000 ppm.

【Effect of the invention】

According to the present invention, by adding soot to the evaporation raw material for the deposition of a selenium-tellurium photophobic layer, fractional distillation of tellurium can be suppressed and a photosensitive layer with a uniform carbon distribution can be obtained. It is possible to obtain an electrophotographic photoreceptor in which variations in sensitivity, dark decay characteristics, etc. are reduced, and copies with stable image density can be made.

[Brief explanation of drawings]

FIG. 1 is a tellurium concentration distribution diagram of a photosensitive layer according to an embodiment of the present invention, FIG. 2 is a tellurium concentration distribution diagram of a conventional photosensitive layer, and FIG.
The figure is a cross-sectional view of an example of a photoreceptor to which the present invention is implemented;
Figure 4 is a cross-sectional view of another example, Figure 5 is a relationship diagram between the amount of tin added to the evaporation raw material for the carrier transport layer and the amount of dark attenuation of the photoreceptor, and Figure 6 is the relationship diagram for the evaporation raw material for the carrier generation layer. Figure 7 is a relationship diagram between the amount of tin added to the evaporation material for the carrier transport layer and the amount of light attenuation of the photoreceptor, and Figure 8 is a relationship diagram between the amount of tin added to the evaporation material for the carrier transport layer and the amount of light attenuation of the photoreceptor. FIG. 3 is a relationship diagram between the amount of tin added to the evaporation raw material for the generation layer and the amount of light attenuation of the photoreceptor. Figure 1 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1) An electrophotographic photoreceptor having a photosensitive layer deposited using a selenium-tellurium alloy as an evaporation raw material, characterized in that tin is added to the evaporation raw material.