JPH0243865Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to an apparatus for depositing a photoconductive material, such as selenium or a selenium alloy, for producing electrophotographic photoreceptors used in dry copying machines or printers. .

[Prior art and its problems]

An electrophotographic photoreceptor is one in which selenium or a selenium alloy is deposited on a conductive cylindrical substrate made of, for example, an aluminum alloy by vacuum deposition. For this purpose, a support body provided in a vacuum chamber that circulates and heats a liquid at a constant temperature is rotated, the substrate to be evaporated is supported on it, and a selenium or selenium alloy evaporation source placed below is heated. Deposit on the substrate. The thickness of the photoconductor vapor deposited film deposited in this manner greatly influences the electrophotographic properties of the photoreceptor, especially the charge acceptance ability, and the thickness varies over the entire surface of one photoreceptor. It is required that there be not only uniformity but also no variation between each photoreceptor.

In order to control the thickness of the deposited film, it is necessary to keep the temperature of the evaporation source constant with high accuracy and to keep the amount of photoconductive material evaporated constant. For this purpose, an evaporation source as shown in FIG. 1 has conventionally been used. This evaporation source houses an inner container 2 containing selenium or a selenium alloy 1, a heating body 3 for heating it with radiant heat to melt and evaporate it, and
An outer container 5 having a slit 4 as an outlet for steam
Consisting of An additional member 6 forming a step is fixed to the bottom of the inner container 2, and a temperature sensor 7 such as a thermocouple is fixed to the upper surface thereof, for example by welding or mechanically. Temperature detector 7 is control device 8
The control device 8 controls the heat output of the heating body 3 according to the detected temperature to keep the temperature of the evaporation material 1 constant, and the amount of the material decreases so that the liquid level reaches the additional body 6. The thermal output of the heating body is cut off by detecting the temperature change when the temperature falls below the upper surface of the temperature sensor 7, that is, the position of the tip of the temperature sensor 7. However, when such an evaporation source is used, especially when a tellurium-based selenium alloy is used as the evaporation material, by repeating evaporation, residues generated by dissolution and evaporation of the evaporation material are deposited on the fixed portions of the temperature sensor 7 and the additional body 6. As a result, the timing at which temperature changes are detected becomes unstable or is not detected at all, and as a result, highly accurate control of the amount of evaporation cannot be achieved.

[Purpose of invention]

Therefore, an object of the present invention is to provide a vapor deposition apparatus for an electrophotographic photoreceptor that is capable of highly accurate temperature control and evaporation amount control even when a tellurium-based selenium alloy is used as the vaporization material.

[Key points of the idea]

The present invention includes an evaporation source having an outer container, an inner container containing an evaporation material, and a heating body disposed between the outer container and the inner container, and a temperature detection part having a tip that is immersed in the melted evaporation material to a predetermined depth. In a vapor deposition apparatus equipped with a detector and a control device that controls and shuts off the heat output of the heating element based on the output signal of the temperature detector, the temperature detector is mounted on a support that protrudes from the inner surface of the side wall of the inner container and is spaced apart from the detection part. The above objective is achieved by supporting the device in a fixed position.

[Example of idea]

FIG. 2 shows an evaporation source and a control device according to an embodiment of the present invention, and parts common to those in FIG. 1 are given the same reference numerals. In this case, the temperature sensor 7, such as a thermocouple, is not attached at its tip, but is fixed by welding or mechanical means to the tip of a screw 9 installed in the side wall as a support for the metal inner container 2 at a midway point. has been done. Of course, the necessary insulation for inputting the output signal of the temperature sensor 7 to the control device 8 must be taken into account. The control device 8 controls the heat output of the heating element 3 according to the detected temperature to keep the temperature of the evaporation material 1 constant, and at the same time, the amount of the material 1 decreases and the liquid level is detected at the tip of the temperature detector 7. The temperature change when the temperature drops from the part 71 is detected and the heat output of the heating body is cut off. If this evaporation source is used for evaporation, melting residues will not accumulate in the detection section 71, so that more accurate temperature changes can be detected. Therefore, highly accurate evaporation amount control can be obtained, and since the detector 7 is not in contact with anything other than the material 1, the temperature can be detected more accurately, and more highly accurate temperature control can be obtained. Note that if it is necessary to change the amount of evaporation in order to change the thickness of the deposited film, the detector 7 and the support 9 may be movably coupled.

[Effect of idea]

In the present invention, a temperature detector for controlling the temperature and amount of evaporation material during the manufacture of electrophotographic photoreceptors is supported by a support mounted on the side wall of the inner container at a position away from the detection section at the tip. In addition, since the detection section is free, accurate temperature or changes in the liquid level of the evaporation material can be detected accurately, and the temperature and evaporation amount of the evaporation material can be controlled with high precision. Using vapor deposition mounting based on the present invention,
For example, a selenium-tellurium alloy containing 15% tellurium
Fill the inner container with 1000g and heat the heating element to 320℃.
After performing evaporation 20 times, it was confirmed that the selenium-tellurium alloy film on the photoreceptor could be controlled within a range of ±2 μm with respect to the target thickness of 70 μm.
Of course, it can also be effectively used for evaporation materials other than selenium-tellurium alloys.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional evaporation source, and FIG. 2 is a sectional view of an evaporation source according to an embodiment of the present invention. 1: Evaporation material, 2: Internal container, 3: Heating body,
5: external container, 7: temperature detector, 71: detection section,
8: Control device.

Claims (1)

[Scope of utility model registration request] An evaporation source having an outer container, an inner container containing an evaporation material, and a heating body disposed between the outer container and the inner container, and a temperature detector having a detection part at a tip that is immersed in the melted evaporation material to a predetermined depth. and a control device that controls and shuts off the heat output of the heating element based on the output signal of the temperature sensor, wherein the temperature sensor is mounted on a support protruding from the inner surface of the side wall of the inner container at a position away from the detection part. A vapor deposition apparatus for an electrophotographic photoreceptor, characterized in that it is supported.