JPS617842A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a sensitive body having high sensitivity and maintaining superior reproducibility and stability even after repeated use by forming an interfacial layer contg. halogen so distributed that the concn. increases gradually and then decreases gradually from an electrically conductive support toward a photosensitive layer between the support and the layer. CONSTITUTION:A pan 32 contg. Te, a pan 33 contg. an Se-Cl alloy, a pan 34 contg. Se and a pan 35 contg. an Se-10wt% Te alloy are placed in a vacuum depositing apparatus 31. A Te layer 22a is formed on the outside periphery of an electrically conductive support 21a by vacuum-depositing Te, and the pan 33 is heated to form an Se layer 22b contg. 30ppm Cl. At this time, Cl is diffused from the layer 22b to the layer 22a so that a continuous concn. distribution shown by a curve A, C is provided. A charge retentive Se layer 23a and a charge generating Se-Te alloy layer 24a are successively formed on the layer 22b to obtain an electrophotographic sensitive body 20. Since the sensitive body 20 has an intermediate layer 22, it maintains superior reproducibility and stability with respect to the electrophotographic characteristics even after repeated use at high speed.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a photoreceptor for electrophotography, more specifically, a photoreceptor used in an electrophotographic device, which has stable electrophotographic characteristics even when used repeatedly. (Prior art) As is well known, in a dry type electrophotographic apparatus, an electrostatic latent image of an original to be copied is formed on a photoreceptor, and this electrostatic latent image is developed with toner. Generally, a method is used in which the process of repeating the process of creating a visible image and transferring this visible image onto a recording sheet is generally used.

The photoreceptor layer of the photoreceptor used in this apparatus has a structure as shown, for example, in Japanese Patent Publication No. 58-29510. That is, as shown in FIG. 1, the photoreceptor layer 10 is formed by forming an interfacial layer 2 described below on a conductive support 1 forming an aluminum drum.
A selenium charge holding JW 43a is formed thereon by vapor deposition, and a selenium-based alloy charge generation layer 3b is further formed thereon by vapor deposition.

Then, the drum having the photoreceptor layer 10 configured in this manner is rotated to form a latent image on the photoreceptor layer 10,
This is visualized and transferred to a recording sheet NC for electrophotographic copying, but as this process is repeated, the image quality of the recording sheet on which the image is formed deteriorates. It will be done. Therefore, in order to maintain good image quality, it is required that the electrophotographic properties of the photoreceptor layer be stable even when used repeatedly. The decrease in the charge level of the photoreceptor layer and the increase in the residual potential when the photoreceptor layer is
i! II (This is a fatal defect for obtaining IR. This defect is obvious when observing the finished recording sheet. The decrease in the charge level 4 appears as a change in the density of characters and lines, for example, and the residual An increase in potential appears as a phenomenon in which areas that should normally be white become a faint black background (referred to as background smudge), and both of these phenomena are typical of image quality deterioration and are inconvenient for electrophotographic equipment. This is a serious problem.

Therefore, conventionally, in order to stabilize the electrophotographic characteristics, the interface layer 2 is formed of a thin film made of heavy metal halides, selenides, metal oxides, etc. that have rectifying properties against the movement of charges. It was set at 5K to control charge movement and prevent a decrease in the electrification level and an increase in residual potential.

However, the thin film-like interfacial layer 2 is attached to the conductive support 1.
In order to form the interface layer 2 on top of the interface layer 2, complicated techniques and equipment are required, and the reproducibility and stability of the interface layer 2 thus formed have always been a problem.

(Objective) An object of the present invention is to provide an electrophotographic photoreceptor with excellent reproducibility and stability of electrophotographic characteristics even when used repeatedly at high sensitivity and high speed.

(Summary) In order to achieve the above object, the present invention is characterized in that an interfacial layer containing halogen is formed on a conductive support, and the distribution is further increased gradually and then continuously decreased. It is.

(Examples) The present invention will be described below based on illustrated examples. First, the principle of the present invention will be explained with reference to FIGS. 2 and 3.

As shown in FIG. 2, the photoreceptor layer 15 according to the present invention is
An interface layer 11 containing a halogen as described later is formed by vapor deposition on the outer peripheral surface of a drum-shaped conductive support 21.
Next, a charge retention layer 26 and a charge generation layer 24 are laminated thereon as photosensitive layers, respectively.

Here, as shown in FIG. 6, the halogen concentration distribution in the interface layer 11 is gradually increased from the conductive support 21 to the charge retention layer 23, and then the halogen concentration distribution in the interface layer 11 is approximately It is formed into a mountain shape that reaches its maximum in the center and then gradually decreases continuously. By forming the concentration distribution of the halogen in this manner, it is possible to prevent extreme concentration differences and the generation of potential barriers at the junction interface of different materials, and it is possible to excellently control the charges moving through the interface layer 11. can.

Next, the present invention will be explained in detail based on FIGS. 4 to 6.

First, the vacuum evaporation apparatus used to create the photoreceptor of this example is constructed as shown in FIG. That is, this vacuum evaporation apparatus 31 has a rotary holder 31a inside thereof, and a conductive support 21a consisting of a drum made of aluminum which has been thoroughly cleaned is fixed to this holder 31a by an appropriate means. Moreover, in the lower part of the vacuum evaporation apparatus 31, there are provided plates 32, 53, 34, 35 for heating tellurium or the like as an evaporation source. Then, a predetermined amount of tellurium is put in the dish 32, and in the same way, selenium/chlorine alloy is put in the dish 63, selenium is put in the dish 34, and selenium/tellurium (tellurium 1% by weight) is put in the dish 35. , respectively. In this state, the device si is evacuated to 5×1Q Torr. Next, by operating the above-mentioned apparatus 31, photoreceptors of Examples 1 to B as described below were prepared.

In the photoreceptor of the first embodiment of the present invention, a conductive support 211 made of an aluminum drum is rotated while being maintained at 70°C, and the plate 62 is first set as an interface /122 as shown in FIG. Heating to an appropriate temperature, the tellurium contained in the envelope 62 is evaporated and the purity is 99.99% or more.
A tellurium layer 22a having a thickness of 0.5 μm is formed, and then the plate 33 is similarly heated to form a selenium layer 22b containing halogen at a concentration of 3 opprn to a thickness of 0.5 μm. After forming the interfacial layer 22 in this way, the temperature of the drum is lowered to 65°C, and the plate 64 is similarly formed.
is heated to form a selenium layer 23a with a thickness of 55 μm as a charge retention layer and a selenium/tellurium alloy layer 24a with a tellurium concentration of 7% and a thickness of 3 μm as a charge generation layer.

In this way, the photoreceptor layer 20 is created.

Each layer is formed as described above, and in order to distribute the /.logon concentration in the interface layer 22 in a mountain shape as described above in the explanation of the principle, the following operations are performed.

That is, as shown in FIG.
A high concentration of halogen, including the single No.mu.gen separated from 2b, adheres to the surface of the tellurium layer 22a, and this adhering surface has the highest concentration. As selenium N25a is approached, the halogen concentration gradually decreases (see curve C in FIG. 5). If the temperature of the drum is maintained at 70° C. during the deposition of the tellurium layer 22a and the selenium layer 22b, the excess concentration of norogen (dotted line B in FIG.
The halogen (see curve A in FIG. 5) gradually decreases while diffusing into the tellurium layer 22a (see curve A in FIG. 5), resulting in a continuous and smooth concentration distribution, and no extreme difference in halogen concentration occurs. In this case, tellurium layer 2
It is possible to prevent the generation of a potential barrier at the bonding interface between the selenium layer 2a and the selenium layer 22b).

Next, in the photoreceptor of the second embodiment of the present invention, the thickness of the tellurium layer 22a is 1.0 μm, as shown in Table 1 below.
The other structure is the same as that of the photoreceptor of the first embodiment.

Similarly, the photoconductor of the third embodiment of the present invention has the same structure as the photoconductor of the first embodiment except that the thickness of the selenium #22b is changed by 1.0 μmpc. .

Similarly, the photoconductor of the fourth embodiment of the present invention has the same structure as the photoconductor of the #11 embodiment except that the halogen concentration of the selenium layer 22b is changed to 100 ppm. .

Similarly, the photoreceptor of the fifth embodiment of the present invention has the same structure as the photoreceptor of the first embodiment except that the temperature of the drum is changed to 80°C.

The photoreceptor is the same as the photoreceptor of the first embodiment, except that the thickness of the selenium layer 23a is changed to 0.1 μm and the thickness of the selenium layer 23a is changed to 50 μm.

In this way, the photoreceptors of Examples @1 to B of the present invention were created, and a conventional photoreceptor without a tellurium layer containing Norogon was created as a comparative example. As shown in Table 1 as a "comparative example", the structure of this photoreceptor is such that the temperature of the drum-shaped conductive support 21a is 75° C.
The thickness of #jf 22a is Q, i ilm.

The thickness of the selenium layer 23a is 50.5 μm, and the tellurium concentration and thickness of the selenium/tellurium alloy layer 24a are the same as those of the photoreceptor of the first embodiment.

Next, the photoreceptors of the first to sixth embodiments according to the present invention and the conventional photoreceptor having no tellurium layer containing halogen were tested in an electrophotographic property evaluation apparatus 41 as shown in FIG. Comparative measurements were made. Here, to outline the configuration of the evaluation device 41, a corona band ↑! is placed at a predetermined position around the drum-shaped photoreceptor 42. 54.3. Exposure lamp 4
4. Potential measuring element 45. An AC corona static eliminator 46 and a static eliminator lamp 47 are arranged sequentially in a clockwise direction.

In place of the photoreceptor 42 of the electrophotographic characteristic evaluation apparatus 41 described above, the photoreceptors of the first to sixth embodiments and the photoreceptor prepared as the comparative example were installed, and the copying process was repeated about 100 times. was applied, and the 4th position of charge, residual potential, etc. before and after that were measured, and the results shown in Table 2 were obtained.

As is clear from Table 2, when the photoreceptor according to the present invention is used, compared to the photoreceptor of the above-mentioned comparative example, there is less change in the charged potential and residual potential before and after fatigue of the photoreceptor.

In the above embodiment, tellurium was used, but in place of the tellurium, for example, bismuth or indium may be used.

Silver or the like may also be used.

Furthermore, even if the thickness of the tellurium layer, halogen concentration, etc. in the above embodiment are set to the following values, the same effects as in the above embodiment can be obtained.

That is, the tellurium layer has a thickness of 50 to 10,000 A, and the halogen-containing muselen layer has a halogen concentration of 10 to 500 P.
It is sufficient if the thickness is 0.1 to 5 μm in pm.

Table 1 Table 2 (Effects) According to the present invention, even if the photoreceptor is used repeatedly, the band 11
There is no change in both the L potential and the residual potential, and even when used in an actual copying machine and operated continuously, it is possible to stably obtain a good image quality without any change in image quality (density change and background smudge phenomenon in 4?). can.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged sectional view of a photoreceptor layer in a conventional electrophotographic photoreceptor. FIG. 2 is a partially enlarged cross-sectional view of a photosensitive integral layer in an electrophotographic photoreceptor for explaining the present invention in detail, and FIG.
A diagram showing the halogen concentration distribution in the interface layer of the photoreceptor layer for an electronic device shown in FIG. 2 above, and FIG. FIG. 5 is a partial enlarged cross-sectional view of the radius R, and FIG. 5 is a diagram showing the halogen concentration distribution in the interface layer of the electrophotographic photoreceptor layer shown in FIG. 4 above. FIG. FIG. 7 is a schematic diagram of the configuration of a vacuum steaming device 1 used to form an electrophotographic photoreceptor layer; FIG. . 1 r 21 + 21 B... rd conductive support (
drum) 2.11.22...φ...interface layer 3a, 23...charge retention 1613b, 2
4...Charge generation layer 22a...Φ・φ・
Tellurium layer 22b... Halogen-containing selenium layer 23a
・・e－・・・Ai-Seleyl- 24a・・・・・・Selenium/tellurium alloy layer patent examiner Representative of Olympus Optical Industry Co., Ltd.
Person Fujikawa 7-dan, 11JI'1・
'BL Map 2Z' η3 Map 4

Claims (1)

[Claims] A photoreceptor used in an electrophotographic device, in which a halogen-containing interface layer is provided between a conductive support and a photosensitive layer formed on the conductive support, and the halogen concentration distribution in this layer is . A photoreceptor for electrophotography, characterized in that the amount gradually increases from the conductive support toward the photosensitive layer and then decreases continuously.