JP2017009622A - Manufacturing method of electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an electrophotographic photoreceptor capable of stabilizing a discharge state and improving film thickness unevenness of a surface protective layer through removing polysilane generated in a vicinity of an exhaust hole while forming a deposition film.SOLUTION: A manufacturing method of an electrophotographic photoreceptor includes: a step of installing a cylindrical electrode including a cylindrical substrate inside a decompressable reaction vessel; a step of forming a photoconduction layer on a cylindrical substrate; and a step of forming a surface protective layer on the photoconduction layer. A gas is blown towards an exhaust hole of the reaction vessel connected to exhaustion means to exhaust the reaction vessel, from a reaction vessel side to an exhaust side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for producing an electrophotographic photosensitive member in which an amorphous silicon (hereinafter also referred to as “a-Si”) deposited film is formed on a substrate by glow discharge plasma CVD (Chemical Vapor Deposition).

  When an a-Si deposited film is formed on a substrate by glow discharge plasma CVD, the deposited film is also formed at a place other than the substrate. Furthermore, it is known that a powdery polymer called polysilane is also formed at the same time and adheres to the inside of the reaction vessel or the exhaust pipe.

  In particular, when the deposited film to be formed is used for an electrophotographic photosensitive member, a film thickness of about 20 to 40 μm is required, so that the amount of polysilane inside the reaction vessel may increase.

  The polysilane remains and adheres to the exhaust pipe and may cause clogging of the pipe. For example, if the exhaust pipe is clogged with polysilane, it may be difficult to control the pressure inside the reaction vessel, and a stable discharge state may not be maintained. As a result, the deposited film characteristics may be adversely affected.

  As a method for improving such a problem, Patent Document 1 discloses a method of removing polysilane remaining in the exhaust pipe during formation of the deposited film by supplying chlorine trifluoride to the exhaust pipe during formation of the deposited film. It is disclosed.

JP 2010-77500 A

  According to the above-described prior art, polysilane generated in the exhaust pipe is removed during the formation of the deposited film, and the deposition film can be formed stably even for a long time.

  However, depending on the formation conditions of the deposited film and the apparatus configuration, polysilane adheres so as to block the opening of the reaction vessel (hereinafter also referred to as “exhaust hole”) provided to exhaust the reaction vessel. There is. In such a case, abnormal discharge or the like may occur during the formation of the surface protective layer, and the film thickness unevenness of the surface protective layer may deteriorate.

  The polysilane generated in the vicinity of the exhaust hole is difficult to remove by the above-described prior art, which is a new problem to be solved.

  The object of the present invention has been made in view of the above problems, and by removing the polysilane generated in the vicinity of the exhaust holes during the formation of the deposited film, the discharge state is stabilized and the film thickness unevenness of the surface protective layer is improved. Another object of the present invention is to provide a method for producing an electrophotographic photoreceptor.

The present invention
Installing a cylindrical electrode including a cylindrical substrate inside a reaction vessel capable of depressurization;
Forming a photoconductive layer on the cylindrical substrate; and
In the method for producing an electrophotographic photosensitive member having a step of forming a surface protective layer on the photoconductive layer,
A method for producing an electrophotographic photosensitive member, characterized in that gas is blown from the reaction container side toward the exhaust side toward an exhaust hole of the reaction container connected to an exhaust means for exhausting the reaction container. .

  The present invention has been made in view of the above problems, and by removing polysilane generated in the vicinity of the exhaust holes during the formation of the deposited film, the discharge state is stabilized and the film thickness unevenness of the surface protective layer is improved. An electrophotographic photoreceptor manufacturing method can be provided.

It is the schematic of the deposited film formation apparatus for implementing this invention. It is a schematic diagram which shows an exhaust plate and an exhaust pipe. It is the graph which showed the change of the electric current value which flows when the voltage at the time of surface layer formation in an Example is applied. It is the graph which showed the change of the electric current value which flows when the voltage at the time of surface layer formation in a comparative example is applied. It is the graph which showed the change of the reflected electric power when applying the high frequency at the time of the surface layer formation in another Example. It is the graph which showed the change of reflected electric power when applying the high frequency at the time of surface layer formation in another comparative example. It is the schematic of another deposited film formation apparatus for implementing this invention. It is the schematic diagram which showed the layer structure of the electrophotographic photoreceptor. It is the schematic for showing an example of the conventional deposited film formation apparatus. It is the schematic diagram which showed the mode of the polysilane of an exhaust hole.

  The configuration of the conventional deposited film forming apparatus shown in FIG. 9 will be described.

  FIGS. 9A and 9B (hereinafter collectively referred to as “FIG. 9”) are schematic diagrams illustrating an example of a manufacturing apparatus (plasma CVD apparatus) for carrying out a conventional method for manufacturing an electrophotographic photosensitive member. FIG. FIG. 9A is a longitudinal sectional view, and FIG. 9B is a transverse sectional view.

  The depressurizable reaction vessel 901 is configured to be exhausted by an exhaust device (not shown) connected to an exhaust pipe 902.

  In forming the deposited film, while evacuating the reaction vessel 901, a source gas is introduced into the reaction vessel 901 from the gas discharge unit 903, and a voltage is applied between the cylindrical substrate 906 and the reaction vessel 901 from the power source 904. . The power source 904 is connected to the rotating shaft 909, and electric power is transmitted to the cylindrical substrate 906 via the rotating shaft 909 and the substrate holder 907.

  By applying a voltage to the cylindrical substrate 906, the reaction vessel 901 becomes a counter electrode of the cylindrical substrate 906, which is a cylindrical electrode, decomposes the source gas, and a deposited film is formed on the cylindrical substrate 906.

  The present inventors faced the problem that the unevenness of the film thickness of the surface protective layer deteriorates when an examination of increasing the film thickness of the photoconductive layer using such a deposited film forming apparatus was performed. Therefore, in order to investigate the cause of the problem, the current value flowing when a voltage was supplied from the power source during the formation of the surface protective layer was monitored. As a result, it was found that the fluctuation of the current value when the film thickness of the photoconductive layer is large is larger than that when the film thickness of the photoconductive layer is thin, which causes the deterioration of the film thickness unevenness of the surface protective layer. I thought that.

  Furthermore, as shown in FIG. 9, the inside of the reaction vessel was observed from the observation window 918 for observation installed in the deposited film forming apparatus. As a result, it was confirmed that flickering of plasma emission occurred in the vicinity of the exhaust hole 916 when the surface protective layer was formed when the thickness of the photoconductive layer was increased. Further, it was found that the amount of polysilane in the vicinity of the exhaust hole 916 was larger than that in the case where the photoconductive layer was thin, and the opening area of the exhaust hole 916 was reduced.

  FIG. 10 is a view showing the state of the opening of the exhaust hole 1016 at the start of the surface protective layer.

  FIG. 10A shows a state when the film thickness of the photoconductive layer is increased, and FIG. 10B shows a state when the film thickness of the photoconductive layer is thin. In the figure, 1019 represents polysilane.

  Therefore, the present inventors presumed the cause of the deterioration of the film thickness unevenness of the surface protective layer, which occurred in the study of increasing the film thickness of the photoconductive layer as follows.

  By increasing the film thickness of the photoconductive layer, the amount of polysilane adhering to the vicinity of the exhaust hole increases, and the opening of the exhaust hole becomes small. It was speculated that this was caused by the change in the state near the exhaust hole during the formation of the surface protective layer, the occurrence of plasma flickering, and the change in the plasma state during the formation of the surface protective layer.

  The present inventors conducted the following experiment and verified whether the above estimation was correct.

A drum having a thick photoconductive layer is formed, and the drum is once taken out before the surface protective layer is formed. Thereafter, the inside of the reaction vessel was cleaned with ClF ₃ gas, and the polysilane inside the reaction vessel was removed. Then, the taken-out drum was installed in the reaction container, and only the surface protective layer was formed. As a result, it was confirmed that the film thickness unevenness of the surface protective layer was good as in the case where the film thickness of the photoconductive layer was thin.

  Further, when observation was carried out from the observation window 918 during the formation of the surface protective layer, polysilane in the vicinity of the exhaust hole was not confirmed, and no flickering of the discharge was confirmed.

  From the above, it can be confirmed that the polysilane in the vicinity of the exhaust hole is removed before forming the surface protective layer, so that the discharge state is stabilized and the film thickness unevenness of the surface protective layer is improved. I was able to verify.

  However, in the production of the electrophotographic photosensitive member by the above-described experimental method, the number of manufacturing steps increases and the manufacturing cost increases.

  Therefore, the present inventors have devised means for removing polysilane adhering to the vicinity of the exhaust hole before forming the surface protective layer. As a result, before the surface protective layer is formed, gas is blown toward the exhaust holes to remove polysilane in the vicinity of the exhaust holes relatively easily, and it does not adversely affect the formation of the deposited film and increases the manufacturing cost. I found a safe way.

  Hereinafter, a specific method will be described in detail with reference to a drawing of a deposited film forming apparatus in which the present invention can be implemented.

  FIGS. 1A and 1B (hereinafter collectively referred to as “FIG. 1”) also show an embodiment of a manufacturing apparatus (plasma CVD apparatus) for carrying out the manufacturing method of the electrophotographic photosensitive member of the present invention. It is a schematic diagram which shows. FIG. 1A is a longitudinal sectional view, and FIG. 1B is a transverse sectional view.

  The pressure-reducible reaction vessel 101 is configured to be exhausted by an exhaust device (not shown) connected to the exhaust pipe 102.

  The cylindrical base 106 is configured to be installed on the rotation shaft 109 by a base holder 107 and an auxiliary member 108. The substrate holder 107 is installed so as to contain the heater 111 for heating, and the cylindrical substrate 106 is heated and maintained at a desired temperature.

  An insulating member 112 is installed inside the reaction vessel 101, and the cylindrical substrate 106 is electrically insulated from the reaction vessel 101.

  In forming the deposited film, while evacuating the reaction vessel 101, a source gas is introduced into the reaction vessel 101 from the gas discharge unit 103, and a voltage is applied from the power source 104. The power source 104 is connected to the rotating shaft 109 via the control unit 105, and electric power is transmitted to the cylindrical substrate 106 via the rotating shaft 109 and the substrate holder 107.

  By applying a voltage to the cylindrical substrate 106, the reaction vessel 101 becomes a counter electrode, the source gas is decomposed, and a deposited film is formed on the cylindrical substrate 106.

  The cylindrical substrate 106 is rotated by the rotation drive of the rotation drive motor 110, and a uniform deposited film is obtained in the circumferential direction.

  As shown by the arrows in the figure, the source gas discharged from the gas discharge unit 103 is configured to be discharged uniformly facing the longitudinal axis of the cylindrical substrate 106.

  The exhaust pipe 102 is connected to the reaction vessel 101 via the exhaust part 113. An exhaust plate 114 is provided at a connection portion between the exhaust unit 113 and the reaction vessel 101, and the exhaust plate 114 is provided with a plurality of exhaust cylinders 115.

  FIG. 2 is a schematic diagram showing the configuration of the exhaust plate and the exhaust cylinder.

  By arranging a plurality of exhaust cylinders 115 and (215) facing the longitudinal direction of the cylindrical base 106, the flow of the gas discharged from the gas discharge unit 103 is uniformly controlled in the longitudinal direction of the cylindrical base 106. Can do. For this reason, a uniform deposited film can be obtained in the longitudinal direction of the cylindrical substrate 106.

  The exhaust plates 114 and (214) also serve to partition the reaction vessel 101 and the exhaust unit 113. The exhaust plates 114 and (214) serve to confine the plasma in the reaction vessel 101 and obtain stable plasma without leaking the plasma to the exhaust unit 113. Therefore, the sizes of the exhaust cylinders 115 and (215) arranged on the exhaust plates 114 and (214) (the inner diameter of the cylinder and the length of the cylinder) are optimally designed. That is, if the inner diameters of the exhaust cylinders 115 and (215) are too large, or the length of the cylinder (the length L in FIG. 2) is too short, the plasma leaks into the exhaust part 113. For this reason, the area of the opening part of an exhaust pipe and the length of a pipe | tube are restrict | limited.

  If the plasma leaks into the exhaust portion 113, efficient deposition film formation is not performed, and the deposition film formation speed may be reduced or the deposition film characteristics may be degraded. Therefore, in order to obtain sufficient photoconductor characteristics, the deposition time becomes long, which may increase the cost.

  During the formation of the deposited film, polysilane is generated inside the reaction vessel 101 and adheres to the inner wall of the reaction vessel 101. Therefore, polysilane adheres also in the vicinity of the opening (hereinafter referred to as an exhaust hole) on the reaction vessel side of the exhaust cylinders 115 and (215). Therefore, depending on the size of the opening area of the exhaust holes 116 and (216) and the film forming conditions, polysilane may adhere to the vicinity of the exhaust holes 116 and (216) as the plasma state is changed.

  As described above, when the inner diameter of the exhaust tube is reduced or the length of the tube is designed to be long in order to suppress the leakage of plasma, the exhaust holes 116, (216) during formation of the deposited film due to the adhesion of polysilane. ) To secure the opening area becomes more severe.

  The gas discharge pipe 117 is configured to blow gas toward the exhaust hole 116. By discharging the gas from the gas discharge pipe 117, the polysilane adhering to the vicinity of the exhaust hole 116 can be removed.

  In the present invention, gas is blown out from the gas discharge pipe 117 before the surface protective layer is started, and the polysilane adhering to the vicinity of the exhaust hole 116 is removed, so that the discharge state at the time of forming the surface protective layer becomes stable. It was confirmed that unevenness was improved.

  In the present invention, the gas blown toward the exhaust hole 116 is hydrogen gas or an inert gas, whereby the effects of the present invention can be obtained. In particular, hydrogen gas and helium gas have a small mass, and the burden on exhaust is small, so that the effects of the present invention are easily obtained. In addition, since the influence on the plasma is small, the influence on the deposited film formation is small. On the other hand, in the case of silane gas or other source gas, there are cases where the influence on the plasma in the vicinity of the exhaust hole and an increase in polysilane may occur, and it is difficult to obtain the effects of the present invention.

  In the present invention, it is preferable to blow the gas toward the exhaust hole from the inside of the reaction vessel toward the exhaust side. For example, when gas is blown from the exhaust side toward the reaction vessel, the polysilane adhering to the vicinity of the exhaust hole is scattered toward the cylindrical substrate, and the polysilane adheres to the cylindrical substrate, It may cause defects in the deposited film.

  In the present invention, as described above, the timing of blowing the gas is performed before the start of the surface protective layer, so that the effect of the present invention can be obtained. In the present invention, “before the start of the surface protective layer” refers to a period from the end of the formation of the photoconductive layer to the start of the formation of the surface protective layer. During this period, the gas is blown onto the polysilane adhering to the vicinity of the exhaust hole 116. The effect of the present invention can be obtained by removing with.

  The effect of the present invention can also be obtained when the gas is blown during formation of the photoconductive layer. This is because polysilane is generated mainly during the formation of the photoconductive layer. By blowing gas toward the exhaust holes 116 during the formation of the photoconductive layer, the amount of polysilane deposited in the vicinity of the exhaust holes 116 can be suppressed. Therefore, when the surface protective layer is formed, the amount of polysilane in the vicinity of the exhaust hole 116 is extremely small, and a stable discharge state can be obtained.

  In addition, depending on the film formation conditions, there is a possibility that the same problem as that of the surface protective layer may occur even when the photoconductive layer is formed. Therefore, it is considered that such a problem can be avoided by blowing the gas during the formation of the photoconductive layer.

  In the present invention, the gas discharge pipe 117 for blowing gas toward the exhaust hole 116 may have any configuration as long as polysilane adhering to the vicinity of the exhaust hole 116 can be effectively removed. However, if the gas discharge pipe is too thick, the area on which the deposited film adheres to the gas discharge pipe increases, and the utilization efficiency of the source gas is lowered. Therefore, it is preferable that the outer diameter is 10 mm or less and the strength can be maintained. The material of the gas discharge tube is preferably a material that can withstand a vacuum state, a temperature atmosphere (about 200 to 400 ° C.) during formation of a deposited film, and plasma. Furthermore, those that do not adversely affect the plasma discharge are preferred. In particular, a ceramic material is particularly preferable because it satisfies all of these conditions.

  In the present invention, the power used for forming the deposited film may be any frequency, but from the viewpoint of uniformity of the deposited film in the longitudinal direction of the cylindrical substrate 106, using a rectangular wave having a frequency of 3 kHz or more and 300 kHz or less, It is effective in the present invention.

  In the plasma CVD apparatus shown in FIG. 1, a rectangular wave having a frequency of 3 kHz or more and 300 kHz or less is applied to the cylindrical substrate 106 to decompose the source gas and form a deposited film on the outer peripheral surface of the cylindrical substrate 106. it can.

  The control unit 105 controls the frequency, duty ratio, and the like of the rectangular wave that is output from the power source 104 and applied between the cylindrical substrate 106 that is installed apart from the reaction vessel 101. In the present invention, the frequency of the rectangular wave is preferably in the range of 3 kHz or more and 300 kHz or less from the VLF band to the LF band. If the frequency is too low, it becomes difficult to suppress the charge-up of the cylindrical substrate, and unevenness in the characteristics of the edge of the deposited film tends to occur. On the other hand, if the frequency becomes too high, a standing wave corresponding to the wavelength is generated, and a portion with a small electric field is formed in the plasma, or the plasma becomes non-uniform due to uneven propagation due to the influence of impedance of the plasma CVD apparatus. As a result, the uniformity of the deposited film tends to decrease.

  In addition, when a rectangular wave having a frequency of 3 kHz or more and 300 kHz or less is used, the voltage is preferably applied to the cylindrical substrate side.

  In the case of discharge in a relatively low frequency band, arc discharge tends to occur depending on conditions. For example, when a voltage is applied to the reaction vessel side, the electrode area on the application side becomes very large compared to the area of the counter electrode, and thus arc discharge may easily occur. Therefore, it is considered that when a voltage is applied to the cylindrical substrate side, stable discharge can be easily obtained. Furthermore, when the cylindrical substrate side is used as the application electrode, it becomes a columnar electrode with very few surface irregularities. For this reason, the movement of the charged particles (ions and electrons) moving on the surface of the application electrode when plasma is formed is smoothly performed. Conversely, when a voltage is applied to the reaction vessel side, it may be difficult to obtain a uniform plasma state due to uneven portions of the reaction vessel (for example, an exhaust portion or a raw material gas introduction portion).

  In the present invention, when a rectangular wave having a frequency of 3 kHz or more and 300 kHz or less is used, a voltage is applied between the cylindrical substrate 106 and the reaction vessel 101 so that the cylindrical substrate side (cylindrical electrode side) is a negative electrode. As a result, the effects of the present invention become remarkable. This is considered due to the relationship with the temperature of polysilane generation. Polysilane has a property of changing from a poly state to a film state depending on the temperature of the generation source. Usually, the film is formed at 200 ° C. or higher, and the generation of polysilane is reduced. Conversely, the lower the temperature, the easier the polysilane grows.

  In the case where the cylindrical substrate 106 side is a negative electrode, energy is given by the positive ions generating plasma colliding with the negative electrode, and the temperature of the cylindrical substrate 106 that becomes the negative electrode rises, but the inner wall of the reaction vessel 106 There is not much temperature rise.

  On the other hand, when the reaction vessel 101 side becomes a negative electrode, energy is given to the reaction vessel 101 side, and the temperature of the inner wall of the reaction vessel 101 rises.

  For this reason, when the cylindrical base | substrate 106 side turns into a negative electrode, the quantity of the polysilane formed in the internal surface of a reaction container increases, and the effect of this invention becomes more remarkable.

  In the present invention, the position of the exhaust hole is not limited. In the above-described example, the exhaust holes are arranged on the side wall (side surface) of the reaction vessel. However, the present invention is effective even in a configuration in which the exhaust holes are arranged on the bottom surface of the reaction vessel.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not restrict | limited to these.

[Example 1]
Using the deposited film forming apparatus shown in FIG. 1, a deposited film is formed on the surface of a cylindrical substrate 102 made of aluminum having a diameter of 84 mm, a length of 381 mm, and a thickness of 3 mm, thereby producing an electrophotographic photosensitive member.

  In this example, a deposited rectangular film was formed by applying a negative rectangular wave having a frequency of 50 kHz and a duty ratio of 70% to the cylindrical substrate. Detailed conditions are shown in Table 1. Under the conditions shown in Table 1, an electrophotographic photosensitive member having the layer structure shown in FIG. 8 was produced.

  The electrophotographic photosensitive member includes a cylindrical substrate 801, a charge injection blocking layer 802, a photoconductive layer 803, and a surface protective layer 804.

  In this embodiment, the gas released from the gas release pipe 117 was hydrogen gas, and was released for 10 minutes at a flow rate of 1000 ml / min (normal) after the photoconductive layer was completed. Thereafter, the gas from the gas discharge pipe 117 was stopped, and a deposited film was formed under the condition of the surface protective layer.

  In the deposited film forming apparatus shown in FIG. 1 used in this embodiment, the exhaust plate and the exhaust pipe are configured as shown in FIG. The inner diameter of the exhaust tube is 30 mm and the length is 100 mm. With this configuration, it is confirmed in advance that there is no plasma leakage to the exhaust part.

  In this example, the state of the opening of the exhaust hole after completion of the photoconductive layer and the state of the opening of the exhaust hole after releasing the gas from the gas discharge pipe were visually observed from the observation window 118. The area of the opening after completion of the photoconductive layer had an opening ratio of about 10%, and polysilane was confirmed. After gas release, the aperture ratio increased to about 80%.

  In this example, during the formation of the surface protective layer, the discharge state was similarly confirmed from the observation window 118, and the current value flowing when a voltage was supplied from the power source 104 during the formation of the surface protective layer was monitored.

  The state of the discharge was not particularly problematic, and no flickering of the discharge was confirmed. The results of monitoring the current value are shown in FIG.

[Comparative Example 1]
In this comparative example, an electrophotographic photosensitive member was manufactured using the deposited film forming apparatus shown in FIG. The manufacturing conditions were the same as in Example 1. In this comparative example, after the photoconductive layer was completed, the surface protective layer was formed without releasing the gas from the gas discharge tube.

  In this comparative example, the discharge state was confirmed from the observation window 118 during the formation of the surface protective layer, and the current value flowing when the voltage was supplied from the power source 104 during the formation of the surface protective layer was monitored.

  As for the state of discharge, flickering of the discharge was confirmed at the exhaust hole. The monitoring result of the current value is shown in FIG. Compared with Example 1, there was much fluctuation in the current value.

[Example 2]
Also in this example, an electrophotographic photosensitive member was manufactured using the deposited film forming apparatus of FIG.

  In this example, the photoconductive layer was formed while hydrogen gas was discharged from the gas discharge pipe 117 at a flow rate of 1000 ml / min (normal) from the start to the end of the photoconductive layer formation. Other conditions were the same as in Example 1.

  In this example, the opening of the exhaust hole was visually observed from the viewing window 118 at the end of the photoconductive layer. The area of the opening of the exhaust hole has an opening ratio of about 95%, and almost no polysilane was observed.

  Also in this example, during the surface protective layer formation, the discharge state is confirmed from the observation window 118 as in Example 1, and the current value that flows when the voltage is supplied from the power source 104 during the surface protective layer formation is also determined. Monitored.

  The state of the discharge was not particularly problematic, and no flickering of the discharge was confirmed. The result of monitoring the current value was the same as that shown in FIG.

Evaluation of Electrophotographic Photoreceptor The following evaluations were performed on the electrophotographic photoreceptors produced in Examples 1 and 2 and Comparative Example 1.

(Uniformity of surface protective layer thickness)
In the axial direction of the produced electrophotographic photosensitive member, the central position of the electrophotographic photosensitive member is 0 mm, and the both sides are spaced by 20 mm (0 mm, ± 20 mm, ± 40 mm, ± 60 mm, ± 80 mm, ± 100 mm, ± 120 mm, A total of 19 points (± 140 mm, ± 160 mm, ± 180 mm), 12 points at intervals of 30 ° in the circumferential direction of each point, and a total of 228 points of film thicknesses were measured.

  The value obtained by dividing the difference between the maximum value and the minimum value of the film thickness at each position by the average film thickness was defined as film thickness uniformity.

  The measurement was performed with a reflection spectroscopic interferometer (MCDP2000 manufactured by Otsuka Electronics Co., Ltd.). The smaller the value, the better the film thickness uniformity.

Furthermore, the evaluation was ranked according to the following criteria.
A ... Less than 3.0% B ... 3.0% or more but less than 4.0% C ... 4.0 or more but less than 5.0% D ... 5.0% or more D It is determined that the film thickness unevenness of the protective layer is large and can be confirmed as an image density difference.

(Light sensitivity uniformity)
The produced electrophotographic electrophotographic photoreceptor was installed in a copying machine modified from iRC6800 manufactured by Canon Inc., and the uniformity of photosensitivity was evaluated.

  A surface potential meter (surface potential meter manufactured by TREK: Model 344, probe: 555P-4) is installed at the central position in the axial direction of the electrophotographic photosensitive member in place of the black developer, and the surface potential is set to 450 V (dark potential). The primary current value and grid voltage value of the main charger were adjusted so that

  Next, the primary current value and grid voltage value of the main charger were made constant, the latent image forming laser (wavelength 655 nm) was irradiated, the light amount of the latent image forming laser was adjusted, and the surface potential meter measured. The surface potential at the center position is set to 50 V (bright potential).

  Thereafter, the axial position of the surface electrometer probe is changed, and the position of the central portion of the electrophotographic photosensitive member is used as a reference, with 19 points in the axial direction at 19 points (0 mm, ± 20 mm, ± 40 mm, ± 60 mm, ± 80 mm, ± 100 mm, Surface potential measurement of ± 120 mm, ± 140 mm, ± 160 mm, ± 180 mm) was performed.

  The measurement of the surface potential at each axial position was performed over one circumference of the electrophotographic photosensitive member, and the average value in the circumferential direction was taken as the photosensitivity characteristic at each axial position. The value obtained by dividing the difference between the maximum value and the minimum value of the photosensitivity characteristics at each axial position by the average photosensitivity characteristic was defined as photosensitivity uniformity. The smaller the value, the better the photosensitivity uniformity.

Furthermore, the evaluation was ranked according to the following criteria.
A ... Less than 2.0% B ... 2.0% or more but less than 3.0% C ... 3.0 or more but less than 4.0% D ... 4.0% or more It is determined that the sensitivity unevenness is large and can be confirmed as an image density difference corresponding to the unevenness.

(Uniformity of total film thickness)
The total film thickness uniformity of the electrophotographic photosensitive member was evaluated by the following method.

  In the axial direction of the produced electrophotographic photosensitive member, the central position of the electrophotographic photosensitive member is 0 cm, and the both sides are spaced by 20 mm (0 mm, ± 20 mm, ± 40 mm, ± 60 mm, ± 80 mm, ± 100 mm, ± 120 mm, The total film thickness of 228 points in total was measured, 19 points in total (± 140 mm, ± 160 mm, ± 180 mm) and 12 points at 30 ° intervals in the circumferential direction of each point.

  The value obtained by dividing the difference between the maximum value and the minimum value of the film thickness at each position by the average film thickness was defined as film thickness uniformity.

  The measurement was performed by an eddy current method with a probe ETA3.3H attached to FISCHERSCOPEmms (manufactured by HELMUTFISCHER). The smaller the value, the better the film thickness uniformity.

Furthermore, the evaluation was ranked according to the following criteria.
A ... Less than 3.0% B ... 3.0% or more but less than 4.0% C ... 4.0 or more but less than 5.0% D ... 5.0% or more It is determined that the film thickness unevenness is large and can be confirmed as an image density difference.

(Charge uniformity)
The charging uniformity was evaluated by the following method.

  The produced electrophotographic electrophotographic photosensitive member was installed in a modified machine of a copying machine iRC6800 (trade name) manufactured by Canon Inc., and the charging uniformity was evaluated.

  A surface potential meter (surface potential meter manufactured by TREK: Model 344, probe: 555P-4) is installed at the central position in the axial direction of the electrophotographic photosensitive member in place of the black developer, and the surface potential is set to 450 V (dark potential). The primary current value and grid voltage value of the main charger were adjusted so that

  The primary current value and grid voltage value of the main charger are fixed, the axial position of the surface electrometer probe is changed, and the central position of the electrophotographic photosensitive member is used as a reference, with 20 points in the axial direction and 19 points (0 mm, ± 20 mm) , ± 40 mm, ± 60 mm, ± 80 mm, ± 100 mm, ± 120 mm, ± 140 mm, ± 160 mm, ± 180 mm).

  The surface potential at each axial position was measured over the entire circumference of the electrophotographic photosensitive member, and the average value in the circumferential direction was taken as the charging characteristic at each axial position.

  The value obtained by dividing the difference between the maximum value and the minimum value of the charging characteristics at each axis position obtained by the average charging characteristics was defined as charging uniformity. The smaller the value, the better the charging uniformity.

Furthermore, the evaluation was ranked according to the following criteria.
A: Less than 2.0% B: 2.0% or more and less than 3.0% C ... 3.0 or more and less than 4.0% D ... 4.0% or more It is determined that the unevenness is large and can be confirmed as an image density difference according to the unevenness.

  Based on the above evaluation results, the overall evaluation was made in four stages A to D. It was judged that the effect of the present invention was obtained by C judgment or more.

  For the evaluation of the comprehensive evaluation, the worst evaluation result was adopted for each item.

  The above evaluation results are summarized in Table 2. As shown in Table 2, the results of evaluation in Examples 1 and 2 of the present invention are superior to those of Comparative Example 1 in which the present invention is not used, and the effects of the present invention are obtained. .

[Example 3]
In this example, an electrophotographic photosensitive member was manufactured under the same conditions as in Example 2 except that the exhaust tube had an inner diameter of 60 mm and a length of 20 mm.

  Also in this example, the opening of the exhaust hole was visually observed from the observation window 118 at the start and end of the photoconductive layer. At the beginning and end of the photoconductive layer, the area of the opening of the exhaust hole has an opening ratio of about 100%, and almost no polysilane was observed.

  Also in this example, during the formation of the surface protective layer, the discharge state was confirmed from the observation window 118 as in Example 1, and the current value during the formation of the surface protective layer was monitored.

  The state of the discharge was not particularly problematic, and no flickering of the discharge was confirmed. The result of monitoring the current value was the same as that shown in FIG.

  The electrophotographic photosensitive member produced in this example was evaluated in the same manner as in Examples 1 and 2, and the results are shown in Table 3. As shown in Table 3, the evaluation results in Example 3 of the present invention were all good as in Example 2.

  However, in order to obtain the same film thickness as in Example 2, the process time required 1.2 times that in Example 2. This seems to be because, during the formation of the photoconductive layer, in the observation from the observation window, a slight leakage of plasma emission can be confirmed in the exhaust portion, and there is a leakage of plasma from the exhaust hole.

[Example 4]
In this example, an electrophotographic photosensitive member was produced under the same conditions as in Example 2 except that He, Ne, and Ar were used as the gas species blown from the gas discharge tube.

  The electrophotographic photosensitive member produced in this example was evaluated in the same manner as in Examples 1 and 2, and the results are shown in Table 4. As shown in Table 4, the evaluation results in Example 4 of the present invention were all good as in Example 2.

[Example 5]
In this example, an electrophotographic photosensitive member was manufactured under the conditions shown in Table 5 using the deposited film forming apparatus shown in FIG. As a power source, a high frequency power source of 13.56 MHz was used, and otherwise, hydrogen gas was supplied at 1000 ml / min (nominal) from the gas discharge pipe 117 from the start to the end of photoconductive layer formation under the same conditions as in Example 2. The photoconductive layer was formed while discharging at a flow rate of

  Also in this example, the opening of the exhaust hole was visually observed from the observation window 118 at the end of the photoconductive layer. The area of the opening of the exhaust hole has an opening ratio of about 95%, and almost no polysilane was observed.

  Also in this example, the discharge state was confirmed from the observation window 118 during the formation of the surface protective layer, and the reflected power of the high frequency power supplied from the power source 704 was monitored during the formation of the surface protective layer.

  The state of the discharge was not particularly problematic, and no flickering of the discharge was confirmed. The result of monitoring the reflected power is shown in FIG.

[Comparative Example 2]
In this comparative example, an electrophotographic photosensitive member was manufactured using the deposited film forming apparatus shown in FIG. The manufacturing conditions were the same as in Example 5. However, in this comparative example, no gas was released from the gas discharge tube during the formation of the photoconductive layer.

  In this comparative example, the discharge state was confirmed from the observation window 118 during the surface protective layer formation, and the reflected power of the high-frequency power supplied from the power source 704 was monitored during the surface protective layer formation.

  As for the state of discharge, flickering of the discharge was confirmed at the exhaust hole. The monitoring result of the reflected power is shown in FIG. Compared with Example 5, the fluctuation of the reflected power was much generated.

  The electrophotographic photosensitive member produced in this example was evaluated in the same manner as in Examples 1 and 2, and the results are shown in Table 6. As shown in Table 6, the effect of the present invention was also obtained in Example 5 of the present invention.

[Example 6]
In this example, a deposited film was formed by applying a rectangular wave having a frequency of 50 kHz and a duty ratio of 70% to the reaction vessel using the deposited film forming apparatus of FIG. Detailed conditions are shown in Table 7.

  Also in this example, as in Example 2, the photoconductive layer was formed while hydrogen gas was discharged from the gas release pipe 117 at a flow rate of 1000 ml / min (normal) from the start to the end of the photoconductive layer formation. Went.

[Comparative Example 3]
In this comparative example, similarly to Example 6, the electrophotographic photosensitive member was manufactured under the conditions shown in Table 7 using the deposited film forming apparatus of FIG.

  In this comparative example, no gas was released from the gas discharge tube during the formation of the photoconductive layer.

  The electrophotographic photoreceptors produced in Example 6 and Comparative Example 3 were evaluated and judged in the same manner as in Examples 1 and 2, respectively.

  The results are summarized in Table 8.

  Also in this example, the effect of the present invention is obtained.

101, 710, 901 Reaction vessel 102, 702, 902 Exhaust piping 103, 703, 903 Gas discharge unit 104, 704, 904 Power source 105, 705, 905 Control unit 106, 706, 906 Cylindrical substrate 107, 707, 907 Substrate holder 108, 708, 908 Auxiliary member 109, 709, 909 Rotating shaft 110, 710, 910 Rotation drive motor 111, 711, 911 Heating heater 112, 712, 912 Insulating member 113, 713, 913 Exhaust part 114, 214, 714 , 914 Exhaust plate 115, 215, 715, 915 Exhaust tube 116, 216, 716, 916 Exhaust hole 117, 717 Gas discharge tube 118, 718, 918 Viewing window 801 Base 802 Charge injection blocking layer 803 Photoconductive layer 804 Surface protective layer

Claims (8)

Installing a cylindrical electrode including a cylindrical substrate inside a reaction vessel capable of depressurization;
Forming a photoconductive layer on the cylindrical substrate; and
In the method for producing an electrophotographic photoreceptor having a step of forming a surface protective layer on the photoconductive layer,
A method for producing an electrophotographic photosensitive member, characterized in that gas is blown from the reaction container side toward the exhaust side toward an exhaust hole of the reaction container connected to an exhaust means for exhausting the reaction container.   The method for producing an electrophotographic photosensitive member according to claim 1, wherein the gas is hydrogen gas.   The method for producing an electrophotographic photosensitive member according to claim 1, wherein the gas is an inert gas.   The method for producing an electrophotographic photosensitive member according to claim 1, wherein the gas is sprayed before the step of forming the surface protective layer.   The method for producing an electrophotographic photosensitive member according to any one of claims 1 to 4, wherein the gas is sprayed in the step of forming the photoconductive layer.   The method for producing an electrophotographic photosensitive member according to claim 1, wherein a voltage is applied between the cylindrical electrode and the reaction vessel so that the cylindrical electrode side becomes a negative electrode.   The method for producing an electrophotographic photosensitive member according to claim 1, wherein the voltage is a rectangular wave having a frequency of 3 kHz to 300 kHz.   The method for producing an electrophotographic photosensitive member according to claim 1, wherein the exhaust hole is provided in a side wall of the reaction vessel.

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