JP2013109148A - Method for manufacturing electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an electrophotographic photoreceptor for suppressing characteristic unevenness of a deposition film in its axial direction.SOLUTION: The method for manufacturing an electrophotographic photoreceptor by a plasma CVD method includes the steps of: (1) introducing a raw material gas to form a deposition film into a reaction chamber that can be decompressed where a columnar electrode including a cylindrical substrate is installed and counter electrodes facing each other and spaced apart from the columnar electrode is included; and (2) supplying power to the columnar electrode from an electric power source to apply an alternating rectangular-wave voltage of a frequency in the range of 3 kHz to 300 kHz between the counter electrode and the columnar electrode, so as to decompose raw material gas and to form a deposition film on the cylindrical substrate. In the method, switching of a power supply via one of the end regions of the columnar electrode and a power supply via the other end region of the columnar electrode is performed at least once in the step (2).

Description

  The present invention relates to a method for producing an electrophotographic photosensitive member by plasma CVD (plasma chemical vapor deposition).

  Conventionally, an electrophotographic photoreceptor using amorphous silicon (hereinafter also referred to as “a-Si”) is manufactured by forming a deposited film such as a photoconductive layer on a cylindrical substrate. As a method for forming a deposited film, there is widely used a method in which a raw material gas for forming a deposited film is decomposed by glow discharge using high frequency in the RF band, and the decomposition product is deposited on a cylindrical substrate, so-called RF plasma CVD method. It has been adopted.

  In recent years, there has been a strong demand for higher image quality of electrophotographic apparatuses, and in response to this, there has been a strong demand for improvements in the uniformity of deposited films (thickness of deposited films and uniformity of film quality). ing.

  In the conventional RF plasma CVD method, since the frequency is 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 is generated due to uneven propagation due to the impedance of the plasma CVD apparatus used. In some cases, it becomes non-uniform, which is a problem in improving the uniformity of the deposited film.

  Patent Document 1 discloses a technique that uses a rectangular wave voltage having a polarity of only one of positive and negative at a frequency of 300 kHz or less. According to Patent Document 1, the uniformity of the deposited film is improved by setting the frequency to 300 kHz or lower.

WO2006 / 134781

  However, regarding the unevenness in the characteristics of the deposited film in the axial direction (axial direction of the cylindrical substrate), there is still room for improvement in the technique disclosed in Patent Document 1.

  FIG. 2 shows an example of a plasma CVD apparatus for applying a rectangular wave voltage having a frequency of 3 kHz or more and 300 kHz or less between the columnar electrode 206 and the counter electrode 204 to form a deposited film on the cylindrical substrates 202A and 202B. It is a schematic diagram which shows. The columnar electrode 206 includes cylindrical base bodies 202A and 202B and base body holders 203A and 203B. 2A is a longitudinal sectional view, and FIG. 2B is a transverse sectional view.

  Power is supplied from the power source 218 to the columnar electrode 206 via the power supply terminal 211, and discharge is generated between the columnar electrode 206 and the grounded counter electrode 204. By this discharge, the deposited film forming raw material gas introduced from the gas block 222 is decomposed to form a deposited film.

  When the deposited film is formed by such a method, there is room for improvement in the unevenness in the axial characteristics of the deposited film to be formed.

  An object of the present invention is to provide a method for producing an electrophotographic photosensitive member in which unevenness in the axial characteristics of a deposited film is suppressed.

  The present inventors have intensively studied to improve the unevenness of the axial characteristics of the deposited film. As a result, the end region (end portion) opposite to the end region (end portion) to which the power supply terminal 211 of the columnar electrode 206 is connected acts as a power reflecting surface, and the incident wave and this reflecting surface It was found that the power distribution due to the combination of the reflected wave and the reflected wave caused the unevenness in the axial characteristics of the deposited film.

  For example, in the plasma CVD apparatus shown in FIG. 2, the end region (end) opposite to the end region (end) to which the power supply terminal 211 is connected is an open end, and strongly reflects electromagnetic waves. To do. The combined wave of the incident wave and the reflected wave from the open end causes unevenness in the axial characteristics of the deposited film.

  For example, in the plasma CVD apparatus shown in FIG. 2, the present inventors also provide a power supply terminal in an end region (end) opposite to the end region (end) to which the power supply terminal 211 is connected. It was found that unevenness in the axial characteristics of the deposited film was improved by installing and alternately supplying power to both end regions (end portions) of the columnar electrode 206.

That is, the present invention
(I) A columnar electrode including a cylindrical substrate is installed therein, and a source gas for forming a deposited film is introduced into a pressure-reducible reaction vessel including a counter electrode spaced apart from and opposed to the columnar electrode. Process,
(Ii) By supplying power to the columnar electrode from a power source, a cross wave voltage having a frequency of 3 kHz to 300 kHz is applied between the counter electrode and the columnar electrode to decompose the source gas. Forming a deposited film on the cylindrical substrate;
In a method for producing an electrophotographic photosensitive member by a plasma CVD method having:
In the step (ii), switching between the supply of electric power via one end region of the columnar electrode and the supply of electric power via the other end region is performed at least once. It is a manufacturing method of a body.

The present invention also provides:
(I) Introducing a source gas for forming a deposited film into a depressurizable reaction vessel that includes a columnar electrode therein and includes a counter electrode including a cylindrical substrate that is spaced apart and opposed to the columnar electrode. And a process of
(Ii) By supplying power to the columnar electrode from a power source, a cross wave voltage having a frequency of 3 kHz to 300 kHz is applied between the counter electrode and the columnar electrode to decompose the source gas. Forming a deposited film on the cylindrical substrate;
In a method for producing an electrophotographic photosensitive member by a plasma CVD method having:
In the step (ii), switching between the supply of electric power via one end region of the columnar electrode and the supply of electric power via the other end region is performed at least once. It is a manufacturing method of a body.

  By using the method for producing an electrophotographic photosensitive member of the present invention, an electrophotographic photosensitive member in which unevenness in the axial characteristics of the deposited film is suppressed can be produced.

It is a schematic diagram which shows the example of the manufacturing apparatus (plasma CVD apparatus) for enforcing the manufacturing method of the electrophotographic photoreceptor of this invention. It is a schematic diagram which shows the example of the manufacturing apparatus (plasma CVD apparatus) used with the manufacturing method of the conventional electrophotographic photoreceptor. It is a figure which shows the example of the nonuniformity of the film thickness of the axial direction of a deposited film. It is a figure for demonstrating the cross-spreading voltage of a rectangular wave. It is a figure for demonstrating the measuring method of a discharge start voltage and a discharge maintenance voltage. It is a schematic diagram which shows the example of the manufacturing apparatus (plasma CVD apparatus) for enforcing the manufacturing method of the electrophotographic photoreceptor of this invention.

  FIG. 1 is a schematic view showing an example of a production apparatus (plasma CVD apparatus) for carrying out the method for producing an electrophotographic photosensitive member of the present invention. FIG. 1A is a longitudinal sectional view, and FIG. 1B is a transverse sectional view.

  A rectangular wave voltage having a frequency of 3 kHz or more and 300 kHz or less is applied between the columnar electrode 106 including the cylindrical substrates 102A and 102B and the substrate holders 103A and 103B, and the counter electrode 104 facing the columnar electrode 106 at a distance. Then, a deposited film is formed on the cylindrical substrates 102A and 102B.

  Power is supplied from the power source 118 to the columnar electrode 106 via the power supply path switching unit 119 and the power supply terminal 111A or the power supply terminal 111B, and a discharge is generated between the columnar electrode 106 and the grounded counter electrode 104. Raise it.

  In the present invention, switching between the supply of power to the columnar electrode 106 via the power supply terminal 111A and the supply of power to the columnar electrode 106 via the power supply terminal 111B is controlled by the control unit 121 to supply power. This is performed by the route switching unit 119. In the step of forming the deposited film (the step (ii)), the power supply path is switched at least once.

  When power is supplied to the columnar electrode 106 via the power supply terminal 111A, the switching terminal 120B in the power supply path switching unit 119 becomes an open end and acts as a power reflection surface. The power distribution resulting from the combination of the incident wave and the reflected wave from the reflecting surface causes unevenness in the axial characteristics of the deposited film.

  FIG. 3A shows the axis of the deposited film formed on the cylindrical substrates 102A and 102B when the deposited film is formed by supplying power to the columnar electrode 106 via the power supply terminal 111A. It is a figure which shows the example of the nonuniformity of the characteristic (film thickness) of a direction.

  When power is supplied to the columnar electrode 106 via the power supply terminal 111B, the switching terminal 120A in the power supply path switching unit 119 becomes an open end and acts as a power reflection surface. The power distribution resulting from the combination of the incident wave and the reflected wave from the reflecting surface causes unevenness in the axial characteristics of the deposited film.

  FIG. 3B shows the axis of the deposited film formed on the cylindrical substrates 102A and 102B when the deposited film is formed by supplying power to the columnar electrode 106 via the power supply terminal 111B. It is a figure which shows the example of the nonuniformity of the characteristic (film thickness) of a direction.

  As can be seen from FIGS. 3A and 3B, when the power supply path is reversed, the shape of unevenness in the axial characteristic (film thickness) of the deposited film is also reversed. Therefore, in the step of forming the deposited film, the power supply path is switched at least once to suppress unevenness in the axial characteristics of the deposited film formed on the cylindrical substrate, and the uniformity of the deposited film in the axial direction. Can be improved.

  In the present invention, the frequency of the cross wave voltage of the rectangular wave is set in the range from 3 kHz to 300 kHz, which is from the VLF band to the LF band. If the frequency is too low, abnormal discharge such as arc or spark tends to occur, and the characteristics of the deposited film tend to be locally deteriorated. In addition, when an abnormal discharge such as an arc or spark occurs, peeling of a minute deposited film (hereinafter also referred to as “film peeling”) tends to occur. When the characteristics of the deposited film are locally deteriorated or minute film peeling occurs, the portion appears as an image defect when the electrophotographic photosensitive member is used in an electrophotographic apparatus. The image defect referred to here is a solid black (for example, when a toner other than black is used, it is expressed as “solid black” for the sake of convenience). A white dot appears on the image, or a black dot appears on the solid white image. (When a toner other than black is used, it is expressed as a “black dot” for the sake of convenience.) This is what is called “pochi”. In addition, even in the case where minute film peeling occurs in the vicinity of the cylindrical substrate, the peeled film piece adheres to the cylindrical substrate, and the deposited film formed on the cylindrical substrate starts from it. In some cases, a film defect is generated, and this also leads to an image defect (pocket). The film defect mentioned here is a part where the characteristics of the deposited film are locally degraded due to electrical damage caused by minute sparks, or a minute film peeling part of the deposited film formed on the cylindrical substrate by minute sparks. Or it is a protrusion produced when the peeled film piece adheres to the cylindrical substrate.

  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 the impedance of the plasma CVD apparatus. As a result, the uniformity of the deposited film tends to decrease.

  In the present invention, by supplying electric power from the power source 118 to the columnar electrode 106, rectangular waves having a frequency of 3 kHz or more and 300 kHz or less are alternately supplied so that the potential of the columnar electrode 106 with respect to the counter electrode 104 is alternately positive and negative. It is preferable to apply a voltage between the counter electrode 104 and the columnar electrode 106.

  When a cross wave voltage of only one of positive and negative polarity is applied, only charged particles of either positive or negative polarity reach the cylindrical substrate, and the cylindrical substrate You may be charged up. More specifically, the charge-up of the cylindrical substrate is a charge-up of the surface of the cylindrical substrate on which the deposited film is formed (≈the surface of the deposited film). Such charge-up of the cylindrical substrate occurs over the entire cylindrical substrate, but the degree of charge-up varies depending on the location due to minute differences in the characteristics of the deposited film and the surface shape of the deposited film. . For this reason, in a cylindrical base | substrate, the difference in an electric field resulting from the difference in the degree of charge-up arises, and it becomes easy to generate | occur | produce a minute spark. Due to the electrical damage at the time of the spark, the characteristics of the deposited film are locally deteriorated or minute film peeling occurs. When minute film peeling occurs, the portion appears as an image defect when the electrophotographic photosensitive member is used in an electrophotographic apparatus.

  In the present invention, the absolute value of the potential difference between the counter electrode and the columnar electrode when the potential of the columnar electrode with respect to the counter electrode becomes positive, and between the counter electrode and the columnar electrode when the potential of the columnar electrode with respect to the counter electrode becomes negative. It is preferable that one of the absolute values of the potential difference is a value less than the absolute value of the discharge sustain voltage and the other is a value greater than or equal to the absolute value of the discharge start voltage.

  The absolute value of the potential difference between the counter electrode and the columnar electrode when the potential of the columnar electrode with respect to the counter electrode becomes positive, and the absolute value of the potential difference between the counter electrode and the columnar electrode when both become negative are values greater than or equal to the absolute value of the discharge start voltage. In this case, the charged particles (ions and electrons) in the plasma reciprocate due to the electric field, and during the reciprocating movement, secondary reactions occur with other charged particles, neutral active species, and source gas, and May be a substance. If this powdery substance is taken into the deposited film, there may be a problem in improving the characteristics of the deposited film.

4A and 4B are diagrams for explaining the cross-seeding voltage of a rectangular wave.
In FIG. 4A, the counter electrode potential is constant at the ground potential, and the cross wave voltage of the rectangular wave is set so that the potential of the columnar electrode (columnar electrode including the cylindrical substrate) with respect to the potential of the counter electrode is alternately positive and negative. It is a figure which shows the change of the electric potential of a columnar electrode at the time of applying between a counter electrode and a columnar electrode. In the example of FIG. 4A, the absolute value of the potential difference between the counter electrode and the columnar electrode when the potential of the columnar electrode with respect to the potential of the counter electrode becomes positive is a value (V1) that is less than the absolute value of the discharge sustaining voltage. The absolute value of the potential difference between the counter electrode and the columnar electrode is a value (V2) that is equal to or greater than the absolute value of the discharge start voltage. In the example of FIG. 4A, since the potential of the counter electrode is constant, the potential of the columnar electrode changes to a rectangular shape as shown in FIG. 4A.

T in FIG. 4A represents the period of the rectangular wave and is determined by the frequency (pulse frequency) of the rectangular wave. In the present invention, a rectangular wave having a frequency of 3 kHz to 300 kHz is used, and a rectangular wave having a frequency of 10 kHz to 100 kHz is preferably used. Further, t1 in FIG. 4A represents a time (period) in which the absolute value of the potential difference between the counter electrode and the columnar electrode is V1, and t2 represents the absolute value of the potential difference between the counter electrode and the columnar electrode. The time (period) which is V2 is represented. In the present invention, a value obtained by dividing t2 by T (t2 / T) is defined as a duty ratio (%).
In the example of FIG. 4A, the duty ratio is 30%.

  Such a rectangular wave cross-seeding voltage is a voltage at which the absolute value of the potential difference between the counter electrode and the columnar electrode becomes V1 when the potential of the columnar electrode with respect to the potential of the counter electrode is positive, and a columnar shape with respect to the potential of the counter electrode When the potential of the electrode becomes negative, a voltage at which the absolute value of the potential difference between the counter electrode and the columnar electrode is V2 is generated from the DC power source, and the switch element is ON / OFF controlled, and the voltage from the DC power source is time-shared. It can be obtained by pulsing. Examples of the switch element include those using a semiconductor switch element such as an IGBT (Insulated Gate Bipolar Transistor) and a MOSFET. According to these switch elements, the duty ratio and frequency can be changed.

  In the period t2 in FIG. 4A, the absolute value of the potential difference between the counter electrode 104 and the columnar electrode 106 is equal to or greater than the absolute value of the discharge start voltage (V2). Discharge occurs and plasma is generated. Neutral active species and cations in the plasma reach the columnar electrode 106, and deposited films are formed on the cylindrical substrates 102A and 102B included in the columnar electrode 106. In this process, the cylindrical bases 102A and 102B included in the columnar electrode 106 are charged up to a positive potential due to the positive charges of the cations. Note that “plasma is generated” means that a discharge occurs between the counter electrode and the columnar electrode, and the source gas is ionized to generate charged particles (ions and electrons). .

  Next, in the period t1, since the absolute value of the potential difference between the counter electrode 104 and the columnar electrode 106 becomes less than the absolute value of the sustaining voltage, the discharge is extinguished and the plasma cannot be maintained. However, the charged particles (ions and electrons) generated in the period t2 do not disappear instantaneously but remain for a while while gradually decaying in the period t1. This state is generally called afterglow, and no new charged particles (ions or electrons) are generated. The lifetime of this afterglow is about several tens of microseconds to several milliseconds. Afterglow life varies with pressure. The higher the pressure, the easier it is to collide with gas molecules and the like, so the life of the afterglow tends to be shortened.

  In this example, since the potential of the columnar electrode 106 becomes positive with respect to the potential of the counter electrode 104 in the afterglow state, negatively charged particles, that is, electrons and anions in the afterglow reach the columnar electrode 106. In this process, the positive potential charge-up of the cylindrical substrates 102A and 102B included in the columnar electrode 106 is alleviated by the negative charges of the electrons and the anions. As a result, minute sparks are suppressed and image defects are suppressed.

  Further, when the absolute value of the difference between the potential of one of the counter electrode and the columnar electrode is equal to or greater than the absolute value of the discharge start voltage, it passes through one end region (end) of the columnar electrode. Supply power to the columnar electrode (power supply to the columnar electrode 106 via the power supply terminal 111A in the case of the plasma CVD apparatus shown in FIG. 1) and the other end region (end) of the columnar electrode. It is preferable to switch to the supply of electric power to the columnar electrode via (the supply of electric power to the columnar electrode 106 via the power supply terminal 111B in the case of the plasma CVD apparatus shown in FIG. 1). Switching when the absolute value of the difference between the potential of one of the counter electrode and the columnar electrode with respect to the other is less than the absolute value of the sustaining voltage means switching, for example, in the afterglow state It is. For example, in the plasma CVD apparatus shown in FIG. 1, when switching is performed in the afterglow state, the charge-up of the cylindrical substrates 102A and 102B included in the columnar electrode 106 may not be sufficiently relaxed. This is because no voltage is applied between the counter electrode 104 and the columnar electrode 106 from the start to the end of switching. As a result, minute sparks are not suppressed, and image defects may not be sufficiently suppressed.

  4A shows a complete rectangular wave. However, in a general commercial power source, the edge of the rectangular wave is rounded, slightly sharp due to overshoot, or V1 or V2. Sometimes ringing may occur. Even in such a case, the effect of the present invention can be obtained.

Next, the discharge start voltage and the discharge sustain voltage will be described in detail.
In the discharge between the counter electrode and the columnar electrode, a small amount of electrons existing between the counter electrode and the columnar electrode are carried to the positive potential side by the electric field, and collide with gas molecules on the way to ionize it. The α action that generates electrons and ions continues. In order to cause this ionization, the energy of electrons at the time of collision needs to be equal to or higher than the ionization energy of gas molecules. The energy when electrons collide with gas molecules increases as the electric field increases, that is, as the voltage applied between the counter electrode and the columnar electrode increases. The voltage applied between the counter electrode and the columnar electrode is gradually increased, and when the energy when the electrons collide with the gas molecule reaches the ionization energy of the gas molecule, the counter electrode and the columnar electrode are Electrons existing during the period increase, and gas molecules continue to be ionized due to collisions, thereby starting discharge. The voltage at the beginning of this discharge is called the discharge start voltage.

  Further, if the voltage applied between the counter electrode and the columnar electrode is lowered from the state where the discharge is started, the discharge cannot be maintained when the voltage becomes lower than a certain voltage. The lowest voltage at which discharge can be maintained is called the discharge sustain voltage. The discharge sustaining voltage is usually lower than the discharge start voltage. This is because the number of electrons in the discharge space is larger in the state where the discharge occurs than in the state where no discharge occurs, and the absolute value of the applied voltage between the counter electrode and the columnar electrode is the absolute value of the discharge start voltage. This is because even if the value is less than the value, if the absolute value of the discharge sustaining voltage is not less than the absolute value of the discharge sustaining voltage, there are more electrons than those necessary for maintaining the discharge.

  In addition, a phenomenon called γ action is one of the reasons why the discharge sustaining voltage is lower than the discharge start voltage. The γ action is a phenomenon in which secondary electrons are emitted from ions generated by ionization of gas molecules when they collide with a counter electrode or a columnar electrode. After the discharge occurs, the electrons generated by this γ action also contribute to the ionization of the gas molecules, so that the discharge can be maintained at a voltage lower than the discharge start voltage.

  Thus, the discharge start voltage and the discharge sustain voltage are dominated by the ionization voltage of the gas molecules and the energy when the electrons collide with the gas molecules. The ionization voltage of gas molecules is determined once the gas type is determined. Further, the energy of electrons when colliding with gas molecules is a function of the electric field strength and the distance traveled until the electrons collide with gas molecules. In other words, it is a function of the applied voltage, the distance between the counter electrode and the columnar electrode, and the moving distance until the electrons collide with the gas molecules. Further, the moving distance until the electrons collide with the gas molecules is a function of gas density, in other words, a function of pressure.

  When a mixed gas composed of a plurality of gas types is used, the gas mixing ratio together with the ionization voltage of each gas is an element that determines the discharge start voltage and the discharge sustain voltage.

  Other factors that affect the discharge start voltage and discharge sustaining voltage include the surface material, shape, and temperature of the counter electrode and columnar electrode. These are the ionization voltage, applied voltage, and the relationship between the counter electrode and columnar electrode. The degree of influence is small compared to the distance and pressure.

  As described above, the discharge start voltage and the discharge sustaining voltage vary depending on the gas type, the mixing ratio of the gas, the distance between the counter electrode and the columnar electrode, and the pressure. Will have a value. That is, if the plasma CVD apparatus to be used and the gas conditions to be used are determined, the discharge start voltage and the discharge sustain voltage are uniquely determined.

  In the present invention, the discharge is caused by a positive or negative electric field rather than the values of the discharge start voltage and the discharge sustaining voltage, and then the discharge is not maintained by the electric field having the opposite polarity. It is important to get an effect. Therefore, although the values of the discharge start voltage and the discharge sustain voltage themselves vary depending on the gas conditions used and the configuration of the plasma CVD apparatus, the effects of the present invention can be obtained if the conditions of the present invention are satisfied. For example, when a mixed gas of silane gas and hydrogen gas is used and when a mixed gas of silane gas, hydrogen gas, and methane gas is used, the discharge start voltage and the discharge sustain voltage are different. However, in either case, the effects of the present invention can be obtained by satisfying the conditions of the present invention.

  In addition, the larger the value (V2) that is equal to or greater than the absolute value of the discharge start voltage, the greater the amount of charge-up of the cylindrical substrate contained in the columnar electrode, but the density of charged particles (ions and electrons) in the afterglow also increases. Therefore, the same effect can be obtained regardless of the magnitude (V2) of the absolute value or higher of the discharge start voltage.

  On the other hand, the value (V1) less than the absolute value of the discharge sustaining voltage is preferably 20% or more with respect to the value (V2) equal to or higher than the absolute value of the discharge start voltage, from the viewpoint of suppressing charge-up. This is because as the value (V1) less than the absolute value of the discharge sustaining voltage is increased, the force for causing charged particles (ions and electrons) in the after glow to reach the columnar electrode increases, and the cylinder included in the columnar electrode This is presumably because the incident density of charges per unit time for suppressing the charge-up of the substrate is increased. However, under the condition of 20% or more, the effect of suppressing the charge-up is only slightly improved. This is because the amount of charged particles (ions and electrons) in the afterglow is limited, so even if the force to reach the columnar electrode is increased, the total amount of charged particles that reach the columnar electrode during the period t1 is large. This is probably because there is no difference.

  Further, the value (V1) less than the absolute value of the sustaining voltage is preferably 95% or less with respect to the absolute value of the sustaining voltage from the viewpoint of stably obtaining the effects of the present invention. By setting it to 95% or less, the absolute value of the sustaining voltage even if there is a fluctuation in the power supply output or a temporary electric field fluctuation in the discharge space due to peeling of deposits from the inner wall surface of the reaction chamber of the plasma CVD apparatus Therefore, the effects of the present invention can be obtained stably and easily.

  Whether or not the discharge has started and whether or not the discharge is maintained includes, for example, a method of judging from voltage-current characteristics and a method of judging by detecting plasma emission.

  5A and 5B are diagrams for explaining a method of measuring the discharge start voltage and the discharge sustain voltage. FIG. 5A is a diagram showing a voltage-current characteristic when a voltage is applied between the counter electrode and the columnar electrode by using the plasma CVD apparatus shown in FIG. 1 to obtain a discharge start voltage. FIG. 5B is a diagram showing voltage-current characteristics when the discharge sustaining voltage is obtained using the plasma CVD apparatus shown in FIG. 1 as in FIG. 5A. From such voltage-current characteristics, it is possible to determine whether or not the discharge has started and whether or not the discharge is maintained, and obtain the discharge start voltage and the discharge sustain voltage.

  When an electrophotographic photosensitive member is to be manufactured by generating a discharge when the potential of the columnar electrode with respect to the potential of the counter electrode becomes negative, a discharge start voltage having a negative potential as shown in the example of FIG. As in the example of 5B, the discharge sustaining voltage having a positive potential is obtained.

  First, the control unit 121 of the plasma CVD apparatus shown in FIG. 1 controlled the output waveform under the conditions of a frequency of 25 kHz and a duty ratio of 30% as a rectangular wave voltage (pulse voltage) in which the voltage is 0 V and the set voltage is repeated. Then, the set voltage was increased from 0 V in a negative direction in 10 V increments (0 V → −10 V → −20 V...), And the current change at that time was measured. As shown in FIG. 5A, when the set voltage is gradually increased from 0 V in the negative direction, a point where the current suddenly increases is observed. The voltage at that time is the discharge start voltage. Note that some current is measured up to the discharge start voltage, but the current does not accompany the discharge, dark current due to the movement of charged particles that exist between the counter electrode and the columnar electrode, This is a leakage current in the plasma CVD apparatus. In FIG. 5A, the current when the set voltage is −650 V is shown as 100%.

  Next, as shown in FIG. 5B, the set voltage is increased to +650 V to cause discharge between the counter electrode and the columnar electrode. From this state, when the set voltage is decreased in increments of 10 V in the direction of 0 V (+650 V → + 640 V → + 630 V...), A point where the current suddenly decreases is observed. The voltage immediately before the current suddenly decreases is the sustaining voltage. In FIG. 5B, the current when the set voltage is +650 V is shown as 100%.

  In the present invention, it is preferable that the two power supply paths to be switched have the same length and / or impedance.

  The duty ratio of the rectangular wave is preferably 20% or more and 80% or less from the viewpoint of achieving both productivity and suppression of charge-up. As the duty ratio increases, the ratio of the period t2 during which the source gas is ionized increases, and the productivity tends to improve. On the other hand, as the duty ratio decreases, the ratio of the period of t1 that relaxes the charge-up of the cylindrical substrate included in the columnar electrode increases, and the level for suppressing the charge-up tends to increase. However, since the afterglow has a lifetime and the amount of charged particles (ions and electrons) in the afterglow is limited, even if the duty ratio is decreased and the period of t1 is increased, the length of the afterglow is increased to some extent. The level to suppress charge-up will not change.

  Note that when the frequency is 3 kHz, the period T is slightly longer than 333 μs. Under such a low frequency condition, when the duty ratio becomes small and the period of t1 becomes long, the afterglow may disappear in the middle of the period of t1, but the period of t2 is short because the period of t1 is long. Thus, since the amount of charge-up of the cylindrical substrate included in the columnar electrode during the period t2 is reduced, the charge-up can be sufficiently mitigated during the lifetime of the afterglow. Further, when the frequency is 300 kHz, the cycle T is slightly over 3.3 μsec. Under such a high frequency condition, when the duty ratio is increased, the period of t1 is shortened. However, the period of t2 is shorter than when the frequency is low, and the cylindrical substrate included in the columnar electrode in the period of t2 is charged. Since the amount of up is small, the charge up can be sufficiently mitigated.

  As described above, the square electrode crossing voltage is changed between the counter electrode and the columnar shape so that the potential of the counter electrode is constant at the ground potential and the potential of the columnar electrode including the cylindrical substrate is alternately positive and negative with respect to the potential of the counter electrode. When the potential of the columnar electrode with respect to the potential of the counter electrode becomes positive, the absolute value of the potential difference between the counter electrode and the columnar electrode becomes a value (V1) less than the absolute value of the discharge sustaining voltage, and is negative The present invention has been described by taking as an example the case where the absolute value of the potential difference between the counter electrode and the columnar electrode becomes a value (V2) that is equal to or greater than the absolute value of the discharge start voltage. If satisfied, the effect of the present invention can be obtained. In other cases, for example, the potential of the counter electrode may be constant at a potential other than the ground potential, the potential of the columnar electrode may be constant at the ground potential or other potential, the potential of the counter electrode and the columnar electrode Neither of these potentials may be constant. In addition, the absolute value of the potential difference between the counter electrode and the columnar electrode when it becomes positive is a value (V2) equal to or greater than the absolute value of the discharge start voltage, and the absolute value of the potential difference between the counter electrode and the columnar electrode when it becomes negative is You may make it become the value (V1) less than the absolute value of a discharge maintenance voltage. Further, a cylindrical substrate may be included in the counter electrode instead of the columnar electrode.

  In the present invention, an electrophotographic photosensitive member is manufactured by forming a deposited film on a cylindrical substrate (the outer peripheral surface of the cylindrical substrate) by a plasma CVD method. Examples of the deposited film include a lower charge injection blocking layer, a photoconductive layer, an upper charge injection blocking layer, and a surface layer. These layers are sequentially stacked from the cylindrical substrate side to manufacture an electrophotographic photosensitive member. It is common.

  The lower charge injection blocking layer is a layer for suppressing (blocking) charge injection from the cylindrical substrate to the photoconductive layer, and is formed of, for example, an a-Si-based material.

  The photoconductive layer is a layer for generating charges by irradiating an electrophotographic photosensitive member with image exposure light such as laser light, and is formed of, for example, an a-Si material. The film thickness of the photoconductive layer is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or more and 60 μm or less.

  The upper charge injection blocking layer is a layer for suppressing (blocking) injection of charges on the surface of the electrophotographic photosensitive member into the photoconductive layer when the surface of the electrophotographic photosensitive member is charged. For example, a-Si It is formed of a system material. In addition, the material of the upper charge injection blocking layer is preferably a material in which carbon (C), boron (B), nitrogen (N) or oxygen (O) is contained in a-Si. The thickness of the upper charge injection blocking layer is preferably 0.01 μm or more and 1 μm or less.

The surface layer is a layer for protecting the surface of the electrophotographic photosensitive member from abrasion, for example, by (hydrogenated) amorphous silicon carbide, (hydrogenated) amorphous silicon nitride, (hydrogenated) amorphous carbon, etc. It is formed. The surface layer preferably has a sufficiently wide optical band gap with respect to the image exposure light so that the image exposure light applied to the electrophotographic photosensitive member is not absorbed. Moreover, it is preferable to have a resistance value (preferably 10 ¹¹ Ω · cm or more) that can sufficiently hold the electrostatic latent image.

  The electrophotographic photosensitive member can be manufactured, for example, by using the plasma CVD apparatus shown in FIG.

  The plasma CVD apparatus shown in FIG. 1 includes a cylindrical reaction vessel 101 for forming a deposited film on the cylindrical substrates 102A and 102B by plasma processing. Further, substrate holders 103A and 103B for holding cylindrical substrates 102A and 102B, and a gas block 122 for supplying a source gas for forming a deposited film into the reaction vessel 101 are provided. The gas block 122 has a structure that is detachable (detachable) from the counter electrode 104.

  The gas block 122 and the gas supply system are connected via a joint member (not shown). By setting it as such a structure, it can replace | exchange for the reaction container of the structure corresponding to manufacture for every kind by replacing only a gas block.

  The gas block 122 becomes a part of the counter electrode 104 while being attached to the reaction vessel 101. The gas block 122 is preferably attached to the reaction vessel 101 so as to have the same potential as other portions of the counter electrode 104. As a result, the entire side wall surface in the reaction vessel 101 including the gas block 122 becomes an electrode, and more uniform plasma can be generated. The material of the gas block 122 is preferably a conductive metal, and aluminum and stainless steel are more preferable from the viewpoint of ease of processing and cost.

Moreover, as a method of attaching the gas block 122, for example, a method of fixing with a conductive screw can be mentioned.
With respect to the shape of the gas block 122, a shape in which the level difference from the inner surface of the other part of the counter electrode 104 is reduced is preferable. Further, the surface of the gas block 122 (the surface on the gas discharge hole side) that forms the same surface as the inner surface of the other part of the counter electrode 104 may be a flat surface, but is the same when the other inner surface of the counter electrode 104 is a curved surface. A curved surface having a curvature is preferable.

  The diameter of the gas discharge hole of the gas block 122 is preferably in the range of 0.5 to 2.0 mm. Furthermore, the accuracy of each gas discharge hole is preferably within ± 20% of the diameter. Depending on the accuracy of the gas discharge hole, not only unevenness of the axial characteristics of the deposited film but also the formation of the deposited film while rotating the cylindrical substrate may cause unevenness of the circumferential characteristics of the deposited film.

  As a material in the vicinity of the gas discharge hole of the gas block 122, an insulating ceramic can be used, but it is preferable. Depending on the deposition film formation conditions, the plasma may tend to concentrate near the gas discharge holes due to the influence of the gas flow (protrusion pressure), so the use of insulating ceramic is effective in suppressing this. Is. Since the gas block 122 can be detached from the counter electrode 104 (can be detached), the gas block can be processed by itself, so that the process of embedding the tubular ceramic component in the vicinity of the gas discharge hole can be easily performed. Examples of the ceramic material include alumina, zirconia, mullite, cordierite, silicon carbide, boron nitride, and aluminum nitride. Among these, alumina, boron nitride, and aluminum nitride are preferable, and alumina is more preferable from the viewpoint of cost and workability.

  In the reaction vessel 101, a space (discharge space) that can be decompressed is formed by the counter electrode 104, the base plate 108, and the upper lid 109. The counter electrode 104 is preferably a constant voltage, and more preferably an earth potential (grounded). By setting the counter electrode 104 to a constant potential, the potential difference between the counter electrode 104 and the other part in the reaction vessel 101 can be kept constant, so that the reproducibility of the characteristics of the electrophotographic photoreceptor to be manufactured is improved. . Further, the grounding of the counter electrode 104 facilitates handling of the plasma CVD apparatus. Note that when the base plate 108 and the upper lid 109 are not grounded, it is preferable to provide an insulating member between the counter electrode 104 and the base plate 108 and the upper lid 109. In the plasma CVD apparatus shown in FIG. 1, all of the counter electrode 104, the base plate 108, and the upper lid 109 are grounded.

  The plasma CVD apparatus shown in FIG. 1 includes a source gas mixing device 114 and a source gas inflow valve 113 that contain a mass flow controller (not shown) for adjusting the flow rate of the source gas.

  Base holders 103A and 103B for holding cylindrical bases 102A and 102B are rotatably supported. The rotation support mechanism includes a power supply terminal 111B that also serves as a rotation support shaft, and a motor 110 that is connected to the power supply terminal 111B with a gear.

  The plasma CVD apparatus shown in FIG. 1 has an exhaust pipe 115 communicated with the exhaust port of the reaction vessel 101, an exhaust main valve 116, and a vacuum pump 117 as an exhaust system. Examples of the vacuum pump include a rotary pump and a mechanical booster pump. With this exhaust system, the inside of the reaction vessel 101 can be maintained at a predetermined pressure while looking at the vacuum gauge 112 provided in the reaction vessel 101.

  The operations of the power supply 118 and the power supply path switching unit 119 are controlled by the control unit 121. The control unit 121 is configured to be able to apply a rectangular wave cross-seeding voltage having a frequency of 3 kHz to 300 kHz between the columnar electrode 106 and the counter electrode 104 by controlling the power supply 118. In addition, the control unit 121 controls the power supply path switching unit 119 to supply power to the columnar electrode 106 via the power supply terminal 111A and to supply power to the columnar electrode 106 via the power supply terminal 111B. It can be switched between supply and supply.

  In the plasma CVD apparatus shown in FIG. 1, the columnar electrode 106 is constituted by cylindrical substrates 102A and 102B and substrate holders 103A and 103B. The columnar electrode 106 is connected to a power source 118 via power supply terminals 111A and 111B. It is connected. The power supply terminals 111A and 111B are insulated from the upper lid 109 and the base plate 108 by the insulating members 105A and 105B.

  The discharge space for forming the deposited film on the cylindrical substrates 102A and 102B includes an insulating plate 107B attached to the grounded counter electrode 104 and the grounded base plate 108, and an insulating plate attached to the grounded upper lid 109. 107A.

Hereinafter, an example of a method for manufacturing an electrophotographic photosensitive member using the plasma CVD apparatus shown in FIG. 1 will be described.
Cylindrical substrates 102A and 102B whose surfaces are mirror-finished using a lathe are mounted on the substrate holders 103A and 103B so as to include a heater (not shown) for heating the cylindrical substrate in the reaction vessel 101. Install. A cylindrical electrode 106 is constituted by the cylindrical base bodies 102A and 102B and the base body holders 103A and 103B.

Next, the source gas inflow valve 113 is opened and the exhaust main valve 116 is opened to exhaust the reaction vessel 101 and the gas block 122 together with exhaust in the gas supply device. When the reading of the vacuum gauge 112 reaches a predetermined pressure (for example, 0.67 Pa or less), an inert gas for heating (for example, argon gas) is introduced from the gas block 122 into the reaction vessel 101. Then, the flow rate of the inert gas for heating, the opening of the exhaust main valve 116, the exhaust speed of the vacuum pump 117, and the like are adjusted so that the inside of the reaction vessel 101 has a predetermined pressure. Thereafter, a temperature controller (not shown) is operated to heat the cylindrical substrates 102A and 102B with a heater (not shown) for heating the cylindrical substrates, and the temperature of the cylindrical substrates 102A and 102B is set to a predetermined temperature (for example, 20). ˜500 ° C.). When the cylindrical base bodies 102A and 102B are heated to a predetermined temperature, the inert gas is gradually stopped. In parallel with this, a source gas for forming a deposited film (amorphous film) (for example, silicon hydride gas such as SiH ₄ and Si ₂ H ₆ , hydrocarbon gas such as CH ₄ and C ₂ H _6, etc.) 1 type is preferably a silicon hydride gas), and a doping gas (for example, B ₂ H ₆ , PH _3, etc.) is mixed from the source gas mixing device 114 and then gradually added into the reaction vessel 101. Introduce. Next, each source gas is adjusted to a predetermined flow rate by a mass flow controller (not shown) in the source gas mixing device 114. At that time, the opening of the exhaust main valve 116 and the exhaust speed of the vacuum pump 117 are adjusted while looking at the vacuum gauge 112 so that the inside of the reaction vessel 101 is maintained at a predetermined pressure (for example, 1 to 100 Pa).

  After completing the preparation for forming the deposited film by the above procedure, the deposited film is formed on the cylindrical substrates 102A and 102B. Specifically, after confirming that the pressure in the reaction vessel 101 (the pressure in the reaction vessel is hereinafter simply referred to as “internal pressure”) is stabilized, the power source 118 is set to a predetermined voltage and controlled. The unit 121 sets a predetermined frequency and duty ratio. Thus, a rectangular wave voltage is applied between the columnar electrode 106 and the counter electrode 104 via the power supply terminal 111A or the power supply terminal 111B, thereby causing glow discharge. Each discharge gas introduced into the reaction vessel 101 is decomposed by this discharge energy, and a predetermined deposited film is formed on the cylindrical substrates 102A and 102B. During the formation of the deposited film, at least once, the control unit 121 controls the power supply path switching unit 119 to supply power to the columnar electrode 106 via the power supply terminal 111A and via the power supply terminal 111B. Switching between power supply to the columnar electrode 106 is performed. Further, the cylindrical base bodies 102A and 102B may be rotated at a predetermined speed by the motor 110 while the deposited film is being formed.

  After forming a deposited film with a desired film thickness, the application of the crossing voltage is stopped, the flow of each source gas into the reaction vessel 101 is stopped, and the reaction vessel is once evacuated to a high vacuum. An electrophotographic photoreceptor can be produced by repeating the above operation.

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

<Example 1 and Comparative Example 1>
In Example 1 and Comparative Example 1, the waveform is the rectangular wave shown in FIG. 4, the frequency is 60 kHz, the cross-sowing voltage is 50%, and the photoconductive layer is deposited. The dependence of electrophotographic characteristics on the switching of the power supply path was investigated.

  Using the plasma CVD apparatus shown in FIG. 1, a deposited film is formed under the conditions shown in Table 1 on a cylindrical base (a cylindrical base made of aluminum having a diameter of 84 mm, a length of 381 mm, and a thickness of 3 mm). Thus, an electrophotographic photosensitive member was produced. At that time, a deposited film was formed in the order of the lower injection blocking layer, the photoconductive layer, the upper injection blocking layer, and the surface layer. The discharge start voltage and the discharge sustain voltage were as shown in Table 1.

  The number of times of power supply path switching in Table 1 refers to the supply of power to the columnar electrode 106 via the power supply terminal 111A and the supply of power to the columnar electrode 106 via the power supply terminal 111B by the supply path switching unit 119. Is the number of times the switch was made. The power supply path was switched when the potential difference between the counter electrode 104 and the columnar electrode 106 was equal to or greater than the absolute value of the discharge sustaining voltage at equal intervals.

The number of times of switching the power supply path when forming the deposited film of each layer was the conditions shown in Table 2.
A total of 40 electrophotographic photoreceptors were produced in 5 batches (5 cases), 1 batch per case and 2 batches per batch.

  The discharge start voltage (negative potential) and the discharge sustain voltage (positive potential) are values measured in advance by the method described above under the pressure and gas conditions in the reaction vessel when the deposited films of the respective layers are formed.

  Ten electrophotographic photoreceptors produced in Example 1 and Comparative Example 1 were evaluated by the following methods. The evaluation results are shown in Table 3.

(Thickness uniformity)
The film thickness of the electrophotographic photosensitive member was measured at the following measurement points.
The center position of the electrophotographic photosensitive member in the axial direction is set to 0 cm, and 9 points (± 2 cm, ± 4 cm, ± 6 cm, ± 8 cm, ± 10 cm, ± 12 cm, ± 14 cm, ± 16 cm, ± 2 cm on both sides) 18 cm), a total of 19 points including the 0 cm position, and 12 points at 30 ° intervals in the circumferential direction at each axial position, and a total of 228 points were measured positions. The value obtained by dividing the difference between the maximum value and the minimum value of the film thickness at each measurement point 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 (trade name) manufactured by HELMUTFISCHER. The smaller the value, the better the film thickness uniformity.

In addition, the average value of the values of 10 electrophotographic photosensitive members was adopted as the value of the film thickness uniformity in each example and comparative example.
When the film thickness uniformity was 2.0% or more, the film thickness unevenness was large, and it was judged that the effect of the present invention was not obtained.

(Image defect)
The image defect was evaluated as follows.

  The manufactured electrophotographic photosensitive member was installed in a modified machine of a copying machine (trade name: iRC6800) manufactured by Canon Inc., which was modified to have a negative charging and reversal development system. In addition, the black developing device of the copying machine is removed, and a surface potential meter (a surface potential meter (trade name: Model 344) and a probe (trade name: Model 555-P) manufactured by Trek) is installed, and an electrophotographic photosensitive member is installed. The surface potential was measured.

  First, a solid white image (electrostatic latent image forming laser non-exposed) is output, the dark part potential of the surface of the electrophotographic photosensitive member is measured, the primary current of the primary charger and the grid voltage are adjusted, and electrophotographic photosensitive The dark part potential of the body surface was adjusted to −450V.

  In order to strictly evaluate the image defects, the images were output under conditions that make it easy for spots to appear. Specifically, by adjusting the DC bias condition of the cyan development condition, an image in which fog (a phenomenon in which toner adheres to a portion that should originally become a non-image area by the development operation) is output. Development at the time of image output was performed only with a developing device using cyan toner.

  The fog density was measured according to the following procedure, and an image for evaluation was output under development conditions where the fog density was in the range of 0.4 to 0.8%. The reflectance of the evaluation image was measured, and the reflectance of unused paper was further measured. The reflectance value of the evaluation image was subtracted from the reflectance value of unused paper to obtain the fog density. The reflectance was measured by attaching an amber filter to a white photometer (trade name: TC-6DS) manufactured by Tokyo Denshoku.

The image output was performed in a normal temperature and humidity environment with a temperature of 23 ° C./humidity of 60% RH. The same applies to the following.
Using 10 sheets of solid white images (laser non-exposure for electrostatic latent image formation) using Canon Marketing Japan Inc. paper A3 paper (product name: CS-814 (81.4 g / m ² )) as output paper ) Was output and the last two images were used for evaluation.

  One circle of the electrophotographic photosensitive member of the image (= about 264 mm from the front end in the paper conveyance direction) × the size of a circle of 0.05 mm or more in a region of 292 mm in image area width (overlapping circles of 0.05 mm) The number of spots (sometimes protruding from a circle) (cyan-colored spots) was counted.

  For the evaluation, for each of the ten electrophotographic photosensitive members of each example and comparative example, the number of spots was counted for each of the two output images, the average value of the four evaluation numbers was calculated, and the number after the decimal point was rounded up to an integer The value of

(Optical memory)
The optical memory was evaluated as follows.
The produced electrophotographic photosensitive member was installed in the modified machine, and the surface potential of the electrophotographic photosensitive member was measured.

  First, measure the dark part potential of the surface of the electrophotographic photosensitive member while performing a solid white image (electrostatic latent image forming laser non-exposure) output operation, adjust the primary current and grid voltage of the primary charger, and Adjustment was made so that the dark potential on the surface of the photoconductor was -450V.

  Next, while performing a solid black image (electrostatic latent image forming laser exposure) output operation, the light portion potential of the surface of the electrophotographic photosensitive member is measured, and the amount of light of the electrostatic latent image forming laser is adjusted to produce an electronic The light portion potential on the surface of the photographic photosensitive member was adjusted to -100V.

  Fixed to the above charging setting and laser exposure setting, 10 solid white images of A3 size, solid black image of one A3 size electrophotographic photosensitive member (solid black for 263 mm of A3, solid white for the other) Image) One sheet, one A3 size solid white image, a total of 12 sheets were continuously output, and the surface potential was measured during that time. The surface potential of the electrophotographic photosensitive member was measured at seven points in the axial direction of the electrophotographic photosensitive member (± 50 mm, ± 100 mm, ± 150 mm with the axial center of the electrophotographic photosensitive member being 0 mm). In the circumferential direction of the electrophotographic photoreceptor, data at 40 points at 9 ° intervals were acquired.

  After the measurement of the surface potential, the potential difference between the positions of the electrophotographic photosensitive member in the same circumferential direction between the dark portion potential one cycle before the solid black image output operation and the dark portion potential one cycle after the solid black image portion output operation at each axial position. Asked.

  Next, the average value of the potential difference at each axial position was calculated, and the value with the largest potential difference was defined as optical memory. In addition, the average value of the value of 10 electrophotographic photoreceptors was adopted for each example and comparative example.

  As can be seen from the evaluation results in Table 3, switching between power supply to the columnar electrode 106 via the power supply terminal 111A and power supply to the columnar electrode 106 via the power supply terminal 111B is performed at least once. As a result, an electrophotographic photosensitive member having excellent characteristics with excellent uniformity of the deposited film can be obtained.

<Example 2 and Comparative Example 2>
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the plasma CVD apparatus shown in FIG. 1 was changed to the plasma CVD apparatus shown in FIG. 6 and the conditions shown in Table 1 were changed to the conditions shown in Table 4. . The discharge start voltage and the discharge sustain voltage were as shown in Table 4. The number of switching of the power supply path when forming the deposited film of the photoconductive layer was the conditions shown in Table 5.

  A total of 40 electrophotographic photosensitive members were evaluated in the same manner as in Example 1 for each of the 10 manufactured conditions. The evaluation results are shown in Table 6.

  As can be seen from the evaluation results in Table 6, switching between power supply to the columnar electrode 606 via the power supply terminal 611A and power supply to the columnar electrode 606 via the power supply terminal 611B is performed at least once. As a result, an electrophotographic photosensitive member having excellent characteristics with excellent uniformity of the deposited film can be obtained.

<Example 3>
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the switching of the power supply path was performed when it was less than the absolute value of the discharge start voltage. The number of switching of the power supply path when forming the deposited film of the lower injection blocking layer, the upper injection blocking layer, and the surface layer was set to 1, and the number of switching of the power supply path when forming the deposited film of the photoconductive layer was set to 10.
Ten manufactured electrophotographic photoreceptors were evaluated in the same manner as in Example 1. Table 7 shows the evaluation results.

<Example 4>
An electrophotographic photosensitive member was produced in the same manner as in Example 2 except that the switching of the power supply path was performed when it was less than the absolute value of the discharge start voltage. The number of switching of the power supply path when forming the deposited film of the lower injection blocking layer, the upper injection blocking layer, and the surface layer was set to 1, and the number of switching of the power supply path when forming the deposited film of the photoconductive layer was set to 10.
Ten manufactured electrophotographic photoreceptors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 8.

  From the evaluation results in Table 3, Table 6, Table 7 and Table 8, the following can be understood. By switching the power supply to the columnar electrodes 106 and 606 via the power supply terminals 111A and 611A and the power supply to the columnar electrodes 106 and 606 via the power supply terminals 111B and 611B at least once. Thus, an electrophotographic photosensitive member having excellent characteristics with excellent uniformity of the deposited film can be obtained. Further, by switching the power supply path when the potential difference between the counter electrodes 104 and 604 and the columnar electrodes 106 and 606 is equal to or larger than the absolute value of the sustaining voltage, an electrophotographic image with particularly few image defects and good characteristics. A photoreceptor can be obtained.

<Example 5>
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the conditions shown in Table 1 were changed to the conditions shown in Table 9. Switching of the power supply path was performed when the potential of the columnar electrode 106 with respect to the counter electrode 104 was V2.

Since V1 in Table 9 is a value that is greater than or equal to the absolute value of the sustaining voltage, it is not exactly V1, but is a value that is compared with V1 of other embodiments, and is represented as “V1” for convenience. .
Ten manufactured electrophotographic photoreceptors were evaluated in the same manner as in Example 1. Table 10 shows the evaluation results.

<Example 6>
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the conditions shown in Table 1 were changed to the conditions shown in Table 11. Switching of the power supply path was performed when the potential of the columnar electrode 106 with respect to the counter electrode 104 was V2.

V1 in Table 11 is 0V, and the potential of the columnar electrode with respect to the potential of the counter electrode is neither positive nor negative. Therefore, it is not exactly V1, but is a value to be compared with V1 of other examples. Therefore, for convenience, it is described as “V1”.
Ten manufactured electrophotographic photoreceptors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 12.

  The following can be understood from the evaluation results of Table 3, Table 10, and Table 12. The uniformity of the deposited film is excellent by switching the power supply to the columnar electrode 106 via the power supply terminal 111A and the power supply to the columnar electrode 106 via the power supply terminal 111B at least once. An electrophotographic photosensitive member having excellent characteristics can be obtained. Further, the potential of the columnar electrode 106 with respect to the counter electrode 104 alternately becomes positive and negative, and one of the potential difference between the two when the potential of the columnar electrode 106 with respect to the counter electrode 104 becomes positive and the potential difference between the two when negative. By setting the value less than the absolute value of the discharge sustaining voltage and the other value equal to or greater than the absolute value of the discharge starting voltage, an electrophotographic photosensitive member having particularly few image defects and good characteristics can be obtained.

<Example 7>
An electrophotographic photoreceptor was produced in the same manner as in Example 1 except that the conditions shown in Table 1 were changed to the conditions shown in Table 13 and the frequencies were as shown in Table 14.

  A total of 30 electrophotographic photosensitive members were evaluated in the same manner as in Example 1 for each of 10 manufactured conditions. The evaluation results are shown in Table 15.

  The following can be seen from the evaluation results in Table 15. Deposition at any frequency is performed by switching power supply to the columnar electrode 106 via the power supply terminal 111A and power supply to the columnar electrode 106 via the power supply terminal 111B at least once. An electrophotographic photosensitive member having excellent characteristics with excellent film uniformity can be obtained.

V1 A value less than the absolute value of the sustaining voltage V2 A value greater than or equal to the absolute value of the discharge start voltage t1 Time (period) during which the absolute value of the potential difference between the electrode and the cylindrical substrate is V1
t2 Time (period) during which the absolute value of the potential difference between the electrode and the cylindrical substrate is V2
T Period of square wave

Claims (3)

(I) A columnar electrode including a cylindrical substrate is installed therein, and a source gas for forming a deposited film is introduced into a pressure-reducible reaction vessel including a counter electrode spaced apart from and opposed to the columnar electrode. Process,
(Ii) By supplying power to the columnar electrode from a power source, a cross wave voltage having a frequency of 3 kHz to 300 kHz is applied between the counter electrode and the columnar electrode to decompose the source gas. Forming a deposited film on the cylindrical substrate;
In a method for producing an electrophotographic photosensitive member by a plasma CVD method having:
In the step (ii), switching between the supply of electric power via one end region of the columnar electrode and the supply of electric power via the other end region is performed at least once. Body manufacturing method. (I) Introducing a source gas for forming a deposited film into a depressurizable reaction vessel that includes a columnar electrode therein and includes a counter electrode including a cylindrical substrate that is spaced apart and opposed to the columnar electrode. And a process of
(Ii) By supplying power to the columnar electrode from a power source, a cross wave voltage having a frequency of 3 kHz to 300 kHz is applied between the counter electrode and the columnar electrode to decompose the source gas. Forming a deposited film on the cylindrical substrate;
In a method for producing an electrophotographic photosensitive member by a plasma CVD method having:
In the step (ii), switching between the supply of electric power via one end region of the columnar electrode and the supply of electric power via the other end region is performed at least once. Body manufacturing method. In the step (ii), by supplying electric power from the power source to the columnar electrode, a rectangular wave having a frequency of 3 kHz to 300 kHz so that the potential of the columnar electrode is alternately positive and negative with respect to the counter electrode. Applying a cross-sowing voltage between the counter electrode and the columnar electrode;
One of the absolute value of the potential difference between the counter electrode and the columnar electrode when the positive and the absolute value of the potential difference between the counter electrode and the columnar electrode when the negative is less than the absolute value of the discharge sustaining voltage. The other is a value greater than the absolute value of the discharge start voltage,
3. The electrophotographic photosensitive member according to claim 1, wherein the switching is performed when an absolute value of a difference between the potential of one of the counter electrode and the columnar electrode is not less than an absolute value of a discharge start voltage. Manufacturing method.

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