JP2006323122A - Electrophotographic photoreceptor and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor which suppresses accumulation of stress due to the material difference between a photoreceptor and a surface protective layer and achieves high printing durability, and to provide a method for manufacturing the same. <P>SOLUTION: The electrophotographic photoreceptor is obtained by stacking a photosensitive layer comprising a charge generating layer 3 and a charge transport layer 2 on a conductive support and further stacking thereon a surface protective layer 1 including an aggregate of minute blocks 1A which comprise carbon or a carbon-based high-hardness material and have no contact with one another. Since the minute blocks 1A are arranged at such predetermined intervals as to keep noncontact, stress does not accumulate in the surface protective layer 1 to improve peeling resistance, accordingly printing durability can be improved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrophotographic photosensitive member for use in an electrophotographic copying machine, a printer, and the like, and more particularly to an electrophotographic photosensitive member having a surface protective layer excellent in peeling resistance on a photosensitive layer, and It relates to the manufacturing method.

  Conventionally, electrophotographic photoreceptors used in electrophotographic copying machines and printers, etc., in which a photosensitive layer mainly composed of selenium is provided on a conductive support, inorganic photoconductive materials such as zinc oxide are used as organic materials In general, those dispersed therein, those using organic photoconductive materials such as phthalocyanine pigments and azo pigments, and those using amorphous silicon-based materials are generally known. In recent years, as the speed of electrophotographic copying machines and higher image quality have increased, environmentally friendly manufacturing has progressed, and high durability is required to maintain high image quality even when used repeatedly for a long time. It has been.

As a factor affecting the life of the photoreceptor, there is wear caused by mechanical stress from a development process, a cleaning process, and the like. As a method for suppressing this wear, a technique of providing a surface protective layer on a photoreceptor is known. For example, there is a technique such as a method of forming a protective layer made of carbon or a high hardness film (referred to as amorphous carbon film, diamond-like carbon, etc.) having carbon as a main component on the surface of the photosensitive layer (for example, Patent Document 1). As disclosed, it has become possible to obtain a photoreceptor with improved surface hardness and excellent wear resistance.
JP-A-61-255352

  However, in the prior art, the wear resistance could be improved by increasing the hardness of the protective film, but due to the difference in material between the photoconductor and the surface protective layer, which occurs due to mechanical stress that is applied for a long time. There was a problem that the accumulation of the coming stress could not be sufficiently relaxed and the surface protective layer would peel off.

  The present invention has been made in order to solve such a conventional problem, and stress is not accumulated in the surface protective film, and the peel resistance is improved, and as a result, the electrophotography is excellent in printing durability. It is an object of the present invention to provide a photoconductor and a manufacturing method thereof.

  In order to solve the above-mentioned problems, an electrophotographic photoreceptor according to the present invention includes an organic photosensitive layer comprising at least a charge generation layer and a charge transport layer, and a surface protective layer, which are sequentially laminated on a conductive support. The protective layer is made of carbon or a high-hardness material mainly composed of carbon, and is made of an aggregate of minute blocks that are not in contact with each other.

  In the method for producing an electrophotographic photoreceptor according to the present invention, an organic photosensitive layer comprising at least a charge generation layer and a charge transport layer is laminated on a conductive support, and carbon or carbon is deposited on the laminated organic photosensitive layer. A thin film made of a high-hardness material as a main component is formed by plasma chemical vapor deposition. Further, a resist film having a pattern of a predetermined micro block shape is formed on the formed high hardness material thin film by photolithography, and the exposed high hardness material thin film other than the micro block shape is removed by an etching process. Next, the electrophotographic photosensitive member is manufactured by removing the resist film formed on the high hardness material thin film.

  According to the configuration of the present invention, stress is not accumulated in the surface protective film by forming the surface protective film with a small block of carbon that is not in contact with each other or an aggregate of high hardness materials mainly composed of carbon. In addition, the peel resistance is improved, and as a result, the printing durability can be improved.

  The electrophotographic photosensitive member according to the first aspect of the present invention is an electrophotographic photosensitive member in which an organic photosensitive layer comprising at least a charge generation layer and a charge transport layer and a surface protective layer are sequentially laminated on a conductive support. The surface protective layer is made of carbon or an aggregate of minute blocks made of a high hardness material mainly composed of carbon and not in contact with each other. With this configuration, since micro blocks made of carbon or a high-hardness material containing carbon as a main component are not in contact with each other, even if stress occurs in any micro block, the influence of the stress on the micro blocks around it No stress buildup occurs.

  In the electrophotographic photosensitive member according to the second aspect of the present invention, the sum of the inner angles of the surface shapes of the individual micro blocks constituting the surface protective layer is any one of 180 °, 360 ° and 720 °, and the micro block One angle in the surface shape is 60 ° to 120 °. With this configuration, adjacent individual micro blocks can be easily and regularly arranged at regular intervals, and toner can be prevented from entering between the micro blocks during toner development or transfer.

  In the electrophotographic photosensitive member according to the third aspect of the present invention, the surface shape of the micro blocks constituting the surface protective layer is an equilateral triangle. With this configuration, adjacent individual micro blocks can be easily arranged regularly at regular intervals, and toner can be prevented from entering between the micro blocks during toner development or transfer.

  In the electrophotographic photosensitive member according to the fourth aspect of the present invention, the surface shape of the micro blocks constituting the surface protective layer is a quadrangle. With this configuration, adjacent individual micro blocks can be easily arranged regularly at regular intervals, and toner can be prevented from entering between the micro blocks during toner transfer. In addition, since the surface shape of the micro block according to the third aspect is larger than that of a regular triangle, the angle of one corner is larger, so that it is less susceptible to stress due to pressing pressure during development or transfer, and the film is resistant to peeling. The sex can be further improved.

  In the electrophotographic photosensitive member according to the fifth aspect of the present invention, the surface shape of the micro blocks constituting the surface protective layer is a regular tetragon. With this configuration, adjacent individual micro blocks can be easily arranged regularly at regular intervals, and toner can be prevented from entering between the micro blocks during toner transfer. In addition, since the surface shape of the micro block according to the third aspect is larger than that of a regular triangle, the angle of one corner is larger, so that it is less susceptible to stress due to pressing pressure during development or transfer, and the film is resistant to peeling. The sex can be further improved.

  In the electrophotographic photosensitive member according to the sixth aspect of the present invention, the surface shape of the micro blocks constituting the surface protective layer is a regular hexagon. With this configuration, adjacent individual micro blocks can be easily arranged regularly at regular intervals, and toner can be prevented from entering between the micro blocks during toner transfer. In addition, since the surface shape of the micro blocks according to the third, fourth and fifth aspects is larger than that of regular triangles, squares and regular squares, the stress on the pressing pressure during development or transfer is large. It becomes difficult to receive, and the peel resistance of the film can be further improved.

  In the electrophotographic photosensitive member according to the seventh aspect of the present invention, the shortest distance between the micro blocks constituting the surface protective layer is in the range of 1 μm to 4 μm. With this configuration, a general toner having an average diameter of 5 μm to 15 μm and a diameter error of plus or minus 0.5 μm can be prevented from entering between minute blocks during development or transfer.

  In the method for producing an electrophotographic photoreceptor according to the eighth aspect of the present invention, an organic photosensitive layer comprising at least a charge generation layer and a charge transport layer is laminated on a conductive support, and carbon is deposited on the laminated organic photosensitive layer. Alternatively, a thin film made of a high hardness material containing carbon as a main component is formed by plasma chemical vapor deposition, and a resist film having a pattern of a predetermined micro block shape is formed on the formed high hardness material thin film by photolithography. The exposed high-hardness material thin film other than the fine block shape is removed by etching, and the resist film formed on the high-hardness material thin film is removed. With this configuration, micro blocks having a desired size and shape can be accurately formed on the surface protective layer.

  Hereinafter, an embodiment of an electrophotographic photoreceptor and a method for producing the same according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiment.

(Embodiment)
FIG. 1 is a schematic sectional side view showing an electrophotographic photosensitive member according to an embodiment of the present invention. In FIG. 1, an electrophotographic photoreceptor 20 has a photosensitive layer composed of a charge generation layer 3 and a charge transport layer 2 laminated on a conductive support 4, and further, carbon or a high hardness containing carbon as a main component. A surface protective layer 1 made of a material and including an aggregate of minute blocks that do not contact each other is laminated.

  2 to 7 are top views showing an electrophotographic photosensitive member according to an embodiment of the present invention. 2 to 7, the surface protective layer 1 includes the surface protective layer 1 on the charge transport layer 2, and the micro blocks 1 </ b> A to 1 </ b> F that are made of carbon or a high hardness material mainly composed of carbon and do not contact each other. Is formed.

  Examples of the conductive support 4 used in the electrophotographic photosensitive member 20 include a conductor, for example, a metal such as aluminum, iron, copper, or an alloy thereof, or a support obtained by conducting a conductive treatment on the surface of the insulator, such as polyester. A material in which a conductive thin film such as gold or silver is formed on an organic material or an insulator such as alumina porcelain can be used.

  As the charge generation material of the charge generation layer 3, an azo pigment such as a metal-based phthalocyanine pigment or a metal-free phthalocyanine pigment containing a metal such as copper or a fluorenone bisazo pigment is used. As organic materials for dispersing and maintaining these charge generation materials, condensation resins such as polyurethane, epoxy resins, and polycarbonates, and polymers such as polystyrene and styrene-butadiene copolymers, and insulating resins such as copolymers can be used. .

  As the charge transporting material of the charge transporting layer 2, electron accepting materials such as tetracyanoethylene, tetracyanoquinone dimethane, and aromatic tertiary amine compounds can be used. In addition, as an organic material for dispersing and holding these charge generating substances, polymers such as polystyrene and styrene-butadiene copolymers and insulating resins such as copolymers can be used.

  Next, the electrophotographic photosensitive member is manufactured as follows by the method for manufacturing the electrophotographic photosensitive member according to the embodiment of the present invention. First, an organic photosensitive layer comprising at least the charge generation layer 3 and the charge transport layer 2 is laminated on the conductive support 4. Next, a thin film made of carbon or a high hardness material containing carbon as a main component is formed on the laminated organic photosensitive layer by a plasma chemical vapor deposition (CVD) method. A resist film having a pattern of a predetermined minute block shape is formed on the formed high-hardness material thin film by photolithography. Next, the exposed high-hardness material thin film other than the minute blocks is removed by etching. Finally, by removing the resist film formed on the high-hardness material thin film, the surface protective layer 1 composed of an aggregate of micro blocks having a predetermined shape is formed.

  When the surface protective layer 1 is formed on the surface of the charge transport layer 2, the surface protective layer 1 is formed by a plasma CVD method using a hydrocarbon gas such as methane or ethane as a main material and a carrier gas such as hydrogen or argon. At this time, the auxiliary gas such as nitrogen gas or oxygen gas may be mixed with the hydrocarbon gas which is the main raw material.

  Hereinafter, the electrophotographic photoreceptor and the method for producing the same according to the present invention will be described more specifically based on Examples and Comparative Examples.

(Example 1)
An aluminum cylindrical support (hereinafter simply referred to as a cylindrical support) is prepared as a conductive support, and this cylindrical support is prepared by adding 10 parts (parts by weight) of a fluorenone bisazo pigment shown in the following (Chemical Formula 1). In the following, simply indicated as parts), 4 parts of polybutyl butyral and 134 parts of 2-butanone were put into a mixed charge generation layer coating solution and dip coated to form a charge generation layer having a thickness of about 0.2 μm. .

  Subsequently, on this charge generation layer, 9 parts of the aromatic tertiary amine compound shown in the following (Chemical Formula 2), 10 parts of polycarbonate, and 95 parts of tetrahydrofuran were mixed and dip coated, A charge transport layer having a thickness of about 40 μm was formed.

  The cylindrical support having the photosensitive layer thus formed was set in a plasma CVD apparatus as shown in FIG. 13 to form a thin film made of a high hardness material mainly composed of carbon. As shown in FIG. 13, the CVD film forming apparatus 5 includes a vacuum vessel 6 in a grounded state. A plurality of substrate holders 7 for holding the substrate 13 are provided inside the vacuum vessel 6 (only one substrate holder 7 is shown in FIG. 13). A pulse high frequency power supply 8 and a pulse bias voltage power supply 9 are connected to the substrate holder 7. A voltage obtained by superimposing a pulse bias voltage and a pulse high-frequency voltage is applied to the substrate 13 through the substrate holder 7.

  Thus, since the voltage which superimposed the pulse high frequency voltage and the negative pulse bias voltage is applied, the ion in the plasma generated around the base | substrate 13 can be attracted reliably. Further, the CVD film forming apparatus 5 is provided with a gas introduction port 10 for introducing a CVD gas into the vacuum vessel 6 from above. A gas discharge port 11 for discharging the CVD gas is provided below the vacuum vessel 6. Further, the CVD film forming apparatus 5 includes a grounding member 12 that accommodates the base 13 held by the base holder 7 inside. The ground member 12 is grounded by being connected to the vacuum vessel 6.

  When the surface protective layer 1 is formed in such a CVD film forming apparatus 5, the surface of the cylindrical support having the photosensitive layer held by the substrate holder 7 is plasma cleaned by etching with hydrogen gas (hereinafter referred to as “cleaning”). ) Specifically, hydrogen gas is introduced from the gas inlet 10, a pulse bias voltage of −1000 V is applied as a pulse high-frequency voltage to the cylindrical support having the photosensitive layer, and the surface of the cylindrical support having the photosensitive layer. To clean. By performing such a cleaning operation, foreign matters on the surface of the cylindrical support having the photosensitive layer can be removed, and the adhesion between the photosensitive layer and the surface protective layer 1 can be further improved. . After cleaning the surface of the cylindrical support having the photosensitive layer in this way, the surface protective layer 1 is formed. The cleaning conditions are as follows.

Hydrogen gas flow rate: 80ccm
Reaction pressure: 0.5 Pa
Pulse bias voltage: -1 kV
RF output: 300W
When the surface protective layer 1 is formed, methane gas is introduced as a CVD gas from the gas inlet 10 as shown in FIG. A voltage obtained by superimposing a negative pulse bias voltage and a pulse high-frequency voltage is applied to a cylindrical support having a photosensitive layer in a state where the inside of the vacuum vessel 6 is filled with methane gas. By applying a pulsed high frequency voltage to a cylindrical support having a photosensitive layer, the hydrocarbon gas in the vacuum vessel 6 is turned into plasma, and the hydrocarbon gas is decomposed by collision of electrons in the plasma with the hydrocarbon gas to generate ions. Generate. On the other hand, by applying a negative pulse bias voltage to a cylindrical support having a photosensitive layer, the surface protection layer 1 is formed by attracting the generated ions to the cylindrical support.

  When forming the surface protective layer 1, the CVD film forming apparatus 5 applies a pulse bias voltage of −2000 V to a cylindrical support having a photosensitive layer as shown in FIG. Thereby, the ions generated by the application of the pulse high-frequency voltage are attracted to the cylindrical support and a part thereof is injected into the charge transport layer 2 constituting the surface of the cylindrical support. That is, carbon is injected into the charge transport layer 2 and the surface protective layer 1 is not simply attached to the charge transport layer 2, but the surface protective layer 1 is formed in the charge transport layer 2 with a mixing layer (transition layer). . At this time, the surface protective layer 1 composed mainly of carbon with an ion implantation layer having a film thickness of 0.1 μm is formed on the surface of the cylindrical support having the photosensitive layer. The conditions for forming the surface protective layer are as follows.

Methane gas flow rate: 120ccm
Reaction pressure: 50 Pa
Pulse bias voltage: -2 kV
RF output: 300W
In order to process the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, a photolithography process and an etching process were performed. A water-soluble negative resist having a film thickness of 1 μm was applied to the surface of the surface protective layer 1 and dried. Next, a mask having a pattern in which an equilateral triangle having a side of 100 μm is adjacent to each other, a point and a point, or a point and a line, or a line and a line with the closest spacing of 4 μm is formed on the surface of the resist film. Covered and irradiated with light to develop the irradiated part. Next, the mask is removed, and the resist at the irradiated portion is removed with a resist remover.

  Further, the cylindrical support was put into an etching apparatus, and an etching process was performed with argon gas, and the surface protective layer 1 composed mainly of carbon from which the resist was removed was removed. Finally, after the cylindrical support is put in a resist removal (ashing) apparatus, ozone is introduced into the ashing chamber and irradiated with ultraviolet rays to ash and remove the developed resist agent, as shown in FIG. A regular triangle having a length of 100 μm is composed of a set of adjacent points, points, or points and lines, or an interval between lines and lines, that is, the shortest distance between the regular triangles is 4 μm. A surface protective layer 1 was formed to produce an electrophotographic photoreceptor.

(Example 2)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the patterns of the micro blocks 1B have 90 ° angles of four angles as shown in FIG. A surface protective layer 1 was formed in the same manner as in Example 1 except that the longest side was a rectangle having a length of 100 μm, and an electrophotographic photosensitive member was produced. Unless otherwise specified, the shortest distance between minute blocks is the same as that in the first embodiment.

(Example 3)
In the process of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, the pattern of the micro blocks 1C has diagonal angles of 120 each as shown in FIG. A surface protective layer 1 was formed in the same manner as in Example 1 except that the surface was a quadrangle having a maximum side length of 100 μm, and an electrophotographic photosensitive member was manufactured.

(Example 4)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the pattern of the micro blocks 1D has a diagonal angle of 120 ° as shown in FIG. The surface protective layer 1 was formed in the same manner as in Example 1 except that it was a quadrangle composed of a combination of 60 ° and the longest side length of 100 μm, and an electrophotographic photosensitive member was produced.

(Example 5)
In the step of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, the pattern of the micro block 1E has a length of 100 μm as shown in FIG. A surface protective layer 1 was formed in the same manner as in Example 1 except that it was quadrangular, and an electrophotographic photosensitive member was produced.

(Example 6)
In the step of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, the pattern of the minute block 1F is a regular six having a side length of 100 μm as shown in FIG. A surface protective layer 1 was formed in the same manner as in Example 1 except that it was square, and an electrophotographic photosensitive member was produced.

(Comparative Example 1)
The surface protective layer 1 is formed in the same manner as in Example 1 except that the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer is not processed into a predetermined block shape. Produced.

(Comparative Example 2)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the pattern of the micro block 1G is a circle having a diameter of 100 μm as shown in FIG. Except for the above, a surface protective layer 1 was formed in the same manner as in Example 1 to prepare an electrophotographic photosensitive member.

(Comparative Example 3)
In the process of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the angle of the three corners as shown in FIG. The surface protective layer 1 was formed in the same manner as in Example 1 except that the shape was a triangle having a length of 100 μm, 60 ° and 90 °, and the longest side, and an electrophotographic photosensitive member was produced.

(Comparative Example 4)
In the process of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the pattern of the micro block 1I has an angle of 90 ° as shown in FIG. The surface protective layer 1 was formed in the same manner as in Example 1 except that the remaining two corners were 45 ° and the longest side was 100 μm in length, thereby producing an electrophotographic photosensitive member. .

(Comparative Example 5)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the pattern of the micro blocks 1J has a diagonal angle of 130 ° as shown in FIG. The surface protective layer 1 was formed in the same manner as in Example 2 except that the longest side was a quadrangle having a length of 100 μm, and an electrophotographic photosensitive member was produced.

(Comparative Example 6)
In the step of processing the carbon formed on the photosensitive layer or the surface protective layer 1 containing carbon as a main component into a predetermined block shape, the pattern of the micro blocks 1K has a diagonal angle of 130 as shown in FIG. A surface protective layer 1 was formed in the same manner as in Example 2 except that it was a quadrangle having an angle of 50 ° and a longest side of 100 μm, and an electrophotographic photosensitive member was produced.

(Example 7)
In the step of processing carbon or carbon-based surface protective layer 1 formed on the photosensitive layer into a predetermined block shape, the same procedure as in Example 1 is performed except that the interval between adjacent micro blocks is 1 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Example 8)
In the step of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, the process is the same as in Example 2 except that the interval between adjacent micro blocks is 1 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

Example 9
In the step of processing carbon or carbon-based surface protective layer 1 formed on the photosensitive layer into a predetermined block shape, the same procedure as in Example 3 is performed except that the interval between adjacent micro blocks is 1 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Example 10)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the same procedure as in Example 4 is performed except that the interval between adjacent micro blocks is 1 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Example 11)
In the step of processing carbon or carbon-based surface protective layer 1 formed on the photosensitive layer into a predetermined block shape, the same procedure as in Example 5 was performed except that the interval between adjacent micro blocks was 1 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

Example 12
In the step of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, the process is the same as in Example 6 except that the interval between adjacent micro blocks is 1 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 7)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the same procedure as in Example 1 is performed except that the interval between adjacent micro blocks is 5 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 8)
In the step of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, the process is the same as in Example 2 except that the interval between adjacent micro blocks is 5 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 9)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, the same procedure as in Example 3 is performed except that the interval between adjacent micro blocks is 5 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 10)
In the step of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, the process is the same as in Example 4 except that the interval between adjacent micro blocks is 5 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 11)
In the step of processing the carbon formed on the photosensitive layer or the surface protective layer 1 mainly composed of carbon into a predetermined block shape, the same procedure as in Example 5 is performed except that the interval between adjacent micro blocks is 5 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 12)
In the step of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, the process is the same as in Example 6 except that the interval between adjacent micro blocks is 5 μm. Thus, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 13)
In the step of processing the carbon or the surface protective layer 1 containing carbon as a main component formed on the photosensitive layer into a predetermined block shape, except that the interval between adjacent micro blocks is 0.5 μm, it is the same as in Example 1. Similarly, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 14)
In the step of processing carbon or carbon-based surface protective layer 1 formed on the photosensitive layer into a predetermined block shape, except that the interval between adjacent micro blocks is 0.5 μm, Example 2 Similarly, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 15)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, except that the interval between adjacent micro blocks is 0.5 μm, Example 3 and Similarly, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 16)
In the step of processing the carbon formed on the photosensitive layer or the surface protective layer 1 containing carbon as a main component into a predetermined block shape, the interval between adjacent micro blocks is 0.5 μm, and Example 4 Similarly, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 17)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, except that the interval between adjacent micro blocks is 0.5 μm, Example 5 and Similarly, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Comparative Example 18)
In the step of processing the carbon or the surface protective layer 1 mainly composed of carbon formed on the photosensitive layer into a predetermined block shape, except that the interval between adjacent micro blocks is 0.5 μm, and Example 6 Similarly, the surface protective layer 1 was formed to produce an electrophotographic photosensitive member.

(Evaluation of electrophotographic photoreceptor)
The electrophotographic photosensitive members produced as in Examples 1 to 12 and Comparative Examples 1 to 18 were mounted on a commercially available copying machine, a paper-passing durability printing test was performed, and the print quality was visually evaluated. went.

  Table 1 shows the results of evaluating the print quality for each number of printed sheets. In Table 1, the evaluation results represent ◯: no image blur, Δ: slight image quality blur, and x: image blur. Further, the evaluation results of the presence or absence of the surface protective film by microscopic observation after printing and the presence or absence of residual toner are also shown in Table 1.

  As is clear from the above (Table 1), the number of printing durability was clearly improved in the example to which the present invention was applied as compared with the comparative example. In addition, among the samples prepared in this example, the surface number of the micro blocks was good in the number of printing durability in the order of regular hexagon, square, and regular triangle. In addition, no peeling or residual toner could be confirmed in any of the samples by microscopic observation after printing. On the other hand, according to the results of Comparative Examples 3 to 6, when at least one of the corners forming the micro block is 60 ° or less, peeling is confirmed in the micro block, and the smaller the angle, or 60 of the corners forming the block, The more the angle of the angle of less than °, the more peeling was observed.

  Further, residual toner could be confirmed in any sample. Furthermore, even if the shape of the minute block is a regular hexagon, a quadrangle, or a regular triangle, the interval between adjacent blocks is 1 μm. Less than the sample, peeling was observed on the surface protective layer, and peeling was not observed when the interval was larger than 4 μm, but many residual toners could be confirmed.

  From the above results, it was found that the electrophotographic photosensitive member of the present invention is more useful than conventional electrophotographic photosensitive members, and that the effect is greatest when the surface shape of the micro block is a regular hexagon.

  The electrophotographic photosensitive member according to the present invention and the method for manufacturing the electrophotographic photosensitive member are formed by forming a surface protective film with a small block of carbon that is not in contact with each other or an aggregate of high-hardness materials mainly composed of carbon. Does not accumulate, the peel resistance is improved, and as a result, the printing durability can be improved. Therefore, the present invention is useful as an electrophotographic photosensitive member having no long-term image blur and having a long life.

1 is a schematic sectional view of an electrophotographic photosensitive member according to an embodiment of the present invention. Top view of electrophotographic photosensitive member according to Example 1 Top view of electrophotographic photosensitive member according to Example 2 Top view of an electrophotographic photosensitive member according to Example 3 Top view of electrophotographic photosensitive member according to Example 4 Top view of electrophotographic photosensitive member according to Example 5 Top view of an electrophotographic photosensitive member according to Example 6 Top view of electrophotographic photosensitive member according to Comparative Example 2 Top view of electrophotographic photosensitive member according to Comparative Example 3 Top view of electrophotographic photosensitive member according to Comparative Example 4 Top view of electrophotographic photosensitive member according to Comparative Example 5 Top view of an electrophotographic photosensitive member according to Comparative Example 6 Schematic which shows an example of the CVD film-forming apparatus used for the manufacturing method of the electrophotographic photoreceptor by one embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface protective layer 1A-1F Micro block 2 Charge transport layer 3 Charge generation layer 4 Conductive support body 5 CVD film-forming apparatus 6 Vacuum container 7 Base holder 8 Pulse high frequency power supply 9 Pulse bias voltage power supply 10 Gas inlet 11 Gas outlet 12 Grounding member 13 Base 20 Electrophotographic photosensitive member

Claims (8)

An electrophotographic photosensitive member in which an organic photosensitive layer comprising at least a charge generation layer and a charge transport layer and a surface protective layer are sequentially laminated on a conductive support,
2. The electrophotographic photosensitive member according to claim 1, wherein the surface protective layer is made of carbon or a high hardness material mainly composed of carbon, and is made of an aggregate of minute blocks that do not contact each other. The sum of the inner angles in the surface shape of the micro block is either 180 °, 360 °, or 720 °, and one angle in the surface shape of the micro block is 60 ° to 120 °. Item 2. The electrophotographic photosensitive member according to Item 1. 2. The electrophotographic photosensitive member according to claim 1, wherein the surface shape of the micro block is an equilateral triangle. The electrophotographic photosensitive member according to claim 1, wherein a surface shape of the micro block is a quadrangle. 2. The electrophotographic photosensitive member according to claim 1, wherein the surface shape of the micro block is a regular square. 2. The electrophotographic photosensitive member according to claim 1, wherein the surface shape of the micro block is a regular hexagon. 7. The electrophotographic photosensitive member according to claim 1, wherein the shortest distance between the micro blocks is in a range of 1 μm to 4 μm. Laminating an organic photosensitive layer comprising at least a charge generation layer and a charge transport layer on a conductive support,
On the laminated organic photosensitive layer, a thin film made of carbon or a high hardness material mainly composed of carbon is formed by plasma chemical vapor deposition,
On the formed high hardness material thin film, a resist film having a predetermined micro block shape pattern is formed by photolithography,
The exposed high-hardness material thin film other than the minute block shape is removed by etching,
A method for producing an electrophotographic photosensitive member, comprising removing the resist film formed on the high-hardness material thin film.

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