JP2006071779A - Method for manufacturing electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an electrophotographic photoreceptor by which quality control for image defects in an a-Si photoreceptor can be accurately carried out by an easy method and spheric projections inducing image defects during continuous use in a commercial scene can be reliably detected. <P>SOLUTION: The method for manufacturing an electrophotographic photoreceptor having at least an amorphous silicon-based photoconductor layer formed on a support includes an inspection step to evaluate an image defect of the photoreceptor. The inspection step is carried out in an environment at humidity higher than a humidity range in a critical region where the number of image defects increases depending on humidity, based on the humidity dependence of the number of image defects preliminarily evaluated by forming images while varying the humidity environment. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is an electrophotographic photosensitive member (hereinafter referred to as an a-Si photosensitive member) formed with an amorphous silicon photoconductive layer, which can be applied to an image forming apparatus using an electrophotographic process such as a copying machine, a printer, and a fax machine. The present invention relates to a manufacturing method having an inspection process.

  2. Description of the Related Art Conventionally, in an image forming apparatus using an a-Si photoreceptor, an image defect that causes white spots or black spots called white spots or black spots on an image due to spherical protrusions of the a-Si photoreceptor has an image quality. There was a case to become the problem above. In view of this, various methods have been proposed in which an inspection method, an inspection apparatus, inspection conditions, and the like are defined for the purpose of detecting image defects in the inspection process of the a-Si photosensitive member.

  Among them, there is one that defines an inspection method and an apparatus for preliminarily revealing and detecting an image defect caused by a spherical protrusion of an a-Si photosensitive member (see, for example, Patent Document 1).

  In addition, there is disclosed that image formation is performed in a normal environment and a high-temperature and high-humidity environment and image defects are evaluated (for example, see Patent Document 2).

Japanese Patent Laid-Open No. 62-189477 Japanese Patent Laid-Open No. 4-120547

  However, since the conventional example does not consider the influence of changes in the humidity environment on the appearance of image defects, there are the following problems.

The a-Si photosensitive member generally decomposes a source gas such as SiH ₄ by a high frequency glow discharge method,
It is manufactured by a plasma CVD method in which an a-Si deposited film is formed on a conductive substrate. In this manufacturing method, powder that does not contribute to the formation of a deposited film on a conductive substrate is inevitably generated. When such powder, chips from cutting of the conductive substrate, and various kinds of dust adhere to the drum during the formation of the a-Si deposited film, these serve as nuclei to form the a-Si deposited film. Abnormal growth may occur partially in a spherical shape. This abnormally grown portion is generally called a spherical protrusion.

Many of the image defects that appear when an image is formed by an image forming apparatus using an a-Si photoreceptor are caused by the spherical protrusions.
The production of a-Si photoreceptors is carried out under conditions that exclude such powders and dusts to a level acceptable for image quality.

  Furthermore, in order to enable good image formation when the image forming apparatus is mounted, image formation is actually performed after manufacture of the a-Si photoreceptor to evaluate image defects, and does not satisfy an acceptable level in image quality. Regarding the photoconductor, an inspection process to be excluded from the shipment is performed in the manufacturing process.

  Furthermore, the demand for higher image quality of an image forming apparatus using an electrophotographic process has been increasing year by year, and the tolerance level in image quality for image defects has become stricter year by year. In such a situation, the above-described conventional inspection process that does not sufficiently consider the influence of changes in the humidity environment on the appearance of image defects results in variations in the evaluation of image defects, thereby allowing an acceptable level in image quality. There is a possibility that a photoconductor that does not satisfy the above condition may not be excluded from the shipment. In addition, due to the low resistance of the spherical protrusions in the process of continuing use in the market, image defects that did not appear at the time of inspection appeared, and photoreceptors that could not maintain good image formation were excluded from the shipment. A problem that has not occurred may have occurred.

  Therefore, in order to prevent these problems, it is necessary to set a stricter tolerance level in the inspection process. Originally, a photoreceptor that satisfies the tolerance level in image quality is also excluded from the shipment, and defective products are rejected. There was an increase.

  Accordingly, the object of the present invention is to carry out the quality control for the image defects of the a-Si photoreceptor more accurately by a simple method, and the spherical shape in which the image defects appear in the process of continuing use in the market. An object of the present invention is to provide a method of manufacturing an electrophotographic photosensitive member that can reliably detect protrusions.

As a result of intensive studies on the spherical projections in which image defects appear in the process of continuing use in the market and the variations in evaluation of image defects, the present inventors have found that such spherical projections are greatly affected by the humidity environment at the time of inspection. Found that it was affected,
Furthermore, the inventors have reached the present invention by obtaining the knowledge that more accurate detection is possible by appropriately controlling the humidity environment of the image forming apparatus main body or the developing device.

  In order to achieve the above object, an invention according to claim 1 is an inspection method for evaluating image defects of a photoconductor in a method of manufacturing an electrophotographic photoconductor in which at least an amorphous silicon photoconductive layer is formed on a support. The inspection step includes a humidity range in a critical region in which the number of image defects increases depending on humidity based on the humidity dependence of the number of image defects evaluated by performing image formation while changing the humidity environment in advance. It is characterized by being carried out in a higher humidity environment.

  According to a second aspect of the present invention, in the method of manufacturing an electrophotographic photosensitive member in which at least an amorphous silicon-based photoconductive layer is formed on a support, the method includes an inspection step of evaluating image defects of the photosensitive member. The process is based on the humidity dependence of the number of image defects evaluated by performing image formation by changing the humidity environment in advance, and in a humidity environment higher than the humidity range of the critical region where the number of image defects increases depending on the humidity. It is characterized by being carried out using a developing device that is always left standing.

  According to a third aspect of the present invention, in the method of manufacturing an electrophotographic photosensitive member in which at least an amorphous silicon-based photoconductive layer is formed on a support, the method includes an inspection step for evaluating image defects of the photosensitive member. The process is based on the humidity dependence of the diameter of the image defect evaluated by performing image formation by changing the humidity environment in advance, and the humidity environment is higher than the humidity range in the critical region where the diameter of the image defect increases depending on the humidity. It is implemented below.

  According to a fourth aspect of the present invention, in the method of manufacturing an electrophotographic photosensitive member in which at least an amorphous silicon photoconductive layer is formed on a support, the method includes an inspection step for evaluating image defects of the photosensitive member. The process is based on the humidity dependence of the diameter of the image defect evaluated by performing image formation by changing the humidity environment in advance, and the humidity is higher than the critical humidity range where the diameter of the image defect increases depending on the humidity. The present invention is characterized in that it is carried out using a developing device that is always left standing.

  The inventors presume the mechanism by which changes in the humidity environment of the image forming apparatus main body or the developing unit affect the appearance of image defects as follows.

  The charging characteristics of the toner in the developing device are easily affected by the humidity environment, and the charge amount tends to be high in a low humidity environment, and conversely, the charge amount tends to be low in a high humidity environment. As a result, in a one-component developing system often used for high-speed copying machines using an a-Si photosensitive member, a phenomenon occurs in which the image density increases in a low humidity environment and conversely the image density decreases in a high humidity environment. There is a case. Therefore, measures are taken to measure the amount of moisture in the air in the main body installation environment at any time using an environmental sensor installed in the main body, and to correct the potential setting according to the environmental dependence of the development characteristics.

  However, such countermeasures generally control the primary charger current and the developing bias for the purpose of matching the image density. Therefore, it is considered that the difference in potential condition due to the humidity environment affects the appearance of spherical protrusions as image defects.

  Therefore, the present inventors have previously evaluated the humidity dependence of the number of image defects, perform image formation in a humidity environment higher than the critical humidity at which the number of image defects begins to increase, and evaluate the image defects. It is presumed that the influence on the appearance of the spherical protrusion as an image defect due to the difference in potential condition is eliminated, and the image defect can be evaluated more accurately.

  Furthermore, evaluation of image defects under a humidity environment higher than the critical humidity is possible even for spherical projections that have not been sufficiently detected by the conventional inspection process and image defects have appeared in the process of continuing use in the market. It is presumed that the difference between the number of image defects in the inspection process and the number of image defects after continued use in the market can be reduced to a level that is not problematic in practice.

  In addition, the present inventors performed image formation using a developing device that was always left in a humidity environment higher than the critical humidity at which the number of image defects starts to increase, and evaluated the image defects. Eliminate environmental dependence, obtain equivalent image density under almost the same potential conditions, eliminate the influence of differences in potential conditions on the appearance of spherical projections as image defects, and simplify evaluation of image defects It is assumed that it can be carried out more accurately in the inspection process.

In addition, the present inventors have also found that the change in the humidity environment of the image forming apparatus main body or the developing device also affects the diameter of the image defect,
Even if the critical humidity at which the diameter of the image defect starts to increase is used, it is presumed that the evaluation similar to the above can be carried out to make the evaluation of the image defect more accurate with a simple inspection process.

  According to the present invention, in the method of manufacturing an a-Si photosensitive member, the quality control for image defects of the a-Si photosensitive member is more accurately performed by a simple method, and the image is processed in the process of continuing use in the market. It is possible to provide an inspection process capable of reliably detecting a spherical protrusion in which a defect appears.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

"A-Si photoreceptor according to the present invention"
First, the structure of a general a-Si photoreceptor will be described. FIG. 1 is a schematic cross-sectional view schematically showing a layer structure of an a-Si photosensitive member according to the present invention.

  In the electrophotographic photoreceptor 100 shown in FIG. 1A, a light receiving layer 102 is provided on a conductive substrate 101. The photoreceptive layer 102 is an a-Si lower charge injection blocking layer 105 in order from the conductive substrate 101 side, and a photoconductive layer comprising a-Si: H or a-Si: (H, X) and having photoconductivity. 103 and an a-SiC-based surface layer 104.

  In the electrophotographic photoreceptor 100 shown in FIG. 1B, a lower charge injection blocking layer 105, a photoconductive layer 103, and a surface layer 104, which are photoreceptive layers 102, are similarly provided on a conductive substrate 101 in this order. Yes. Furthermore, the photoconductive layer 103 is composed of a first layer region 1031 and a second layer region 1032, and functional separation is achieved. Further, interface control is performed in which the interface between the photoconductive layer 103 and the surface layer 104 is continuously changed to suppress interface reflection.

  The electrophotographic photosensitive member 100 shown in FIG. 1C is formed on the conductive substrate 101, which is the light receiving layer 102, ie, the lower charge injection blocking layer 105, the photoconductive layer 103, and the a-SiC-based upper charge injection blocking. A layer 106 and a surface layer 104 are provided in this order. Further, interface control is performed in which the interface between the photoconductive layer 103 and the upper charge injection blocking layer 106 and between the upper charge injection blocking layer 106 and the surface layer 104 is continuously changed to suppress interface reflection.

  The impurity atoms contained in each of these layers are atoms belonging to Group 13 of the periodic table that gives p-type conduction characteristics (hereinafter abbreviated as Group 13 atoms) or Group 15 of the periodic table that gives n-type conduction characteristics. By selecting from among the atoms to which it belongs (hereinafter abbreviated as group 15 atom), etc., it becomes possible to control the charge polarity such as positive charge or negative charge.

  Further, the surface layer 104 contains a-SiC (H, X) containing hydrogen atoms and halogen atoms as necessary, a silicon atom as a base material, nitrogen atoms and, if necessary, hydrogen atoms and halogen atoms contained. It may be formed of a-SiN (H, X), aC (H, X) containing a carbon atom as a base material and containing a hydrogen atom and a halogen atom as necessary.

  Hereinafter, the conductive substrate and each functional layer constituting the a-Si photoreceptor will be described in more detail.

<Conductive substrate>
Examples of the material for the conductive substrate used in the present invention include metals such as Al, Cr, Mo, Au, In, Nb, Te, V, Ti, and Fe, and alloys thereof such as stainless steel.

  In addition, as a material for the substrate, a film or sheet of a synthetic resin such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polystyrene, or polyamide, or an electrically insulating material such as glass or ceramic is used. The surface on the side where the receiving layer is formed can be subjected to a conductive treatment and used as a conductive substrate.

  The shape of the conductive substrate used can be a smooth surface or a cylindrical type or endless belt type having a minute uneven surface, and the thickness is appropriately set so that a desired electrophotographic photosensitive member can be formed. decide. When flexibility as an electrophotographic photosensitive member is required, it can be made as thin as possible within a range where the function as a conductive substrate can be sufficiently exhibited. However, the conductive substrate is usually preferably 10 μm or more from the viewpoint of production and handling, such as mechanical strength.

<Photoconductive layer>
For the photoconductive layer formed on the conductive substrate and constituting at least a part of the photoreceptive layer, numerical conditions of film forming parameters are appropriately set so that desired characteristics can be obtained, for example, by a vacuum deposition layer forming method, Further, the raw material gas to be used is selected and manufactured. Specifically, glow discharge method (low frequency CVD method, high frequency CVD method or alternating current discharge CVD method such as microwave CVD method, or direct current discharge CVD method), sputtering method, vacuum deposition method, ion plating method, It can be produced by various thin film deposition methods such as a photo CVD method and a thermal CVD method.

  These thin film deposition methods are appropriately selected and adopted depending on factors such as manufacturing conditions, degree of load under capital investment, manufacturing scale, and characteristics desired for the electrophotographic photosensitive member to be produced. The high frequency glow discharge method is preferred because the control of the conditions for producing the electrophotographic photosensitive member is relatively easy.

  In order to form the photoconductive layer by the glow discharge method, basically, a source gas for supplying Si that can supply silicon atoms (Si), and an H supply that can supply hydrogen atoms (H) as needed. And a raw material gas for supplying X that can supply halogen atoms (X) are introduced in a desired gas state into a reaction vessel that can be depressurized to cause glow discharge in the reaction vessel. A layer made of a-Si: H or a-Si: (H, X) may be formed on a predetermined conductive substrate that is previously set at a predetermined position.

  Hydrogen atoms in the photoconductive layer and further halogen atoms added as necessary compensate for dangling bonds of silicon atoms in the layer, improving the layer quality, particularly improving the photoconductivity and charge retention characteristics. When the hydrogen atom content or the halogen atom is added, the sum of the hydrogen atom and halogen atom content is preferably 1 to 40 atom% based on the total amount of the constituent atoms.

As substances that can serve as Si supply gas, gaseous substances such as SiH ₄ , Si ₂ H ₆ , Si ₃ H ₈ , Si ₄ H ₁₀ , or silicon hydrides (silanes) that can be gasified are effectively used. Further, SiH ₄ and Si ₂ H ₆ are preferable from the viewpoints of easy handling at the time of layer preparation, good Si supply efficiency, and the like.

In order to control the introduction rate of hydrogen atoms structurally by introducing hydrogen atoms into the photoconductive layer to be formed, these gases are further desired to be H ₂ , He, silicon compound gas containing hydrogen atoms, etc. The layer may be formed in a mixed atmosphere. In addition, each gas may be mixed not only in a single type but also in a plurality of types at a predetermined mixing ratio.

Preferable examples of the raw material gas for supplying the halogen atom include gaseous substances such as halogen gas, halides, interhalogen compounds containing halogen, silane derivatives substituted with halogen, and halogenated compounds that can be gasified. Further, a gaseous substance containing silicon atoms and halogen atoms as constituent elements, or a silicon hydride compound containing a halogen atom that can be gasified can also be mentioned as effective. Specific examples include halogen compounds such as fluorine gas (F ₂ ), BrF, ClF, ClF ₃ , BrF ₃ , BrF ₅ , IF ₃ , IF ₇ . Specific examples of silicon compounds containing halogen atoms, so-called silane derivatives substituted with halogen atoms, include silicon fluorides such as SiH ₄ and Si ₂ H ₆ .

  Furthermore, in the present invention, it is preferable that the photoconductive layer contains an atom for controlling conductivity as required. Atoms for controlling conductivity may be contained in a state of being uniformly distributed in the photoconductive layer, or there may be a portion containing them in a non-uniform distribution state in the layer thickness direction.

  Furthermore, in the present invention, functional separation can be achieved by changing the content of atoms that control conductivity in the first and second layer regions of the photoconductive layer. In particular, when it is contained in a non-uniform distribution state in the layer thickness direction, the distribution state is preferably reduced from the conductive substrate side to the surface layer side, and the second layer region is compared with the first layer region. It is more preferable to make it contain in the distribution state that content of a layer area | region decreases. In addition, it is also effective to contain in a distributed state in which the content in the layer thickness direction decreases toward the surface side only in the second layer region.

  Examples of the atoms that control conductivity include so-called impurity atoms in the semiconductor field, and group 13 atoms that give p-type conduction characteristics and group 15 atoms that give n-type conduction characteristics can be used.

  Specifically, group 13 atoms include boron (B), aluminum (Al), gallium (Ga), indium (In), thallium (Tl), etc., with B, Al, and Ga being particularly preferred. . The group 15 atom includes phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), etc., and P and As are particularly preferable.

The content of atoms controlling the conductivity contained in the photoconductive layer is preferably 5 × 10 ^{14 to} 5 × 10 ¹⁸ atoms / cm ³ , more preferably 1 × 10 ¹⁵ to 1 × 10 ¹⁸ atoms / cm. ³ and optimally 5 × 10 ^{15 to} 5 × 10 ¹⁷ atoms / cm ³ .

  In order to structurally introduce the atoms for controlling the conductivity, when forming the layer, the source material of the gas for supplying the atoms for controlling the conductivity is in a gas state to form the photoconductive layer in the reaction vessel. What is necessary is just to introduce with other gas. As a material that can be used as a source material for the atom supply gas for controlling conductivity, it is desirable to employ a gaseous material at normal temperature and pressure, or a material that can be easily gasified at least under the conditions of layer formation.

Specifically, as a raw material for introducing such group 13 atoms, for introducing boron atoms, B ₂ H ₆ , B ₄ H ₁₀ , B ₅ H ₉ , B ₅ H ₁₁ , B ₆ H ₁₀ , Boron hydrides such as B ₆ H ₁₂ and B ₆ H ₁₄ , BF ₃ , BCl ₃ , BBr ₃
And boron halides. In addition, AlCl ₃ , GaCl ₃ , Ga (CH ₃ ) ₃ , InCl ₃ , TlCl _{3 and the} like can also be mentioned.

Further, as a raw material for introducing a group 15 atom, specifically for introducing a phosphorus atom, phosphorus hydride such as PH ₃ and P ₂ H4, PF ₃
And phosphorus halides such as PCl ₃ . In addition, AsH ₃ , AsF ₃ , AsF ₅ , AsCl ₃ , SbHv, SbF ₅ , BiH _{3 and the} like can also be mentioned.

Further, the starting material for introducing atoms for controlling the conductivity may be diluted with H ₂ and / or He if necessary.

  In the present invention, the layer thickness of the photoconductive layer is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economic effects, etc., preferably 10 to 50 μm, more preferably 20 to 45 μm, optimally It is desirable that the thickness is 25 to 40 μm. If the layer thickness is less than 10 μm, the electrophotographic characteristics such as charging ability and sensitivity may be insufficient in practical use. If the layer thickness is more than 50 μm, the photoconductive layer may be manufactured for a long time and the manufacturing cost may be increased. is there.

  In the present invention, the thickness of the second layer region of the photoconductive layer is preferably 0.5 μm or more and 15 μm or less.

  If the film thickness of the second layer region is thinner than 0.5 μm, the light absorption amount of the laser and the LED becomes small, the light reaches the deep part of the first layer region, and the ghost level and the linearity of the sensitivity are May decrease. On the other hand, if it is thicker than 15 μm, the residual potential and dark decay increase, and the sensitivity may decrease.

  In order to form the photoconductive layer described above, it is necessary to appropriately set the mixing ratio between the Si supply gas and the dilution gas, the gas pressure in the reaction vessel, the discharge power, and the conductive substrate temperature.

The flow rate of H2 and / or He used as the dilution gas is appropriately selected in accordance with the layer design, but H2 with respect to the Si supply gas.
It is desirable to control He and / or He in the range of 0.5 to 20 times volume, preferably 1 to 15 times volume, and most preferably 1 to 10 times volume.

Similarly, the optimum gas pressure in the reaction vessel is appropriately selected according to the layer design, but preferably 1 × 10 ⁻² to 1 × 10 ³ Pa, more preferably 5 × 10 ^{−2 to} 5 × 10 ² Pa, Optimally, it is set to 1 × 10 ⁻¹ to 1 × 10 ² Pa.

  Similarly, the optimum range of the discharge power is also appropriately selected according to the layer design, but the ratio of the discharge power [W] to the flow rate [mL / min (normal)] of the gas for supplying Si is preferably 0.5 to 20. Is preferably set in the range of 1-12.

  Further, the temperature of the conductive substrate is appropriately selected in accordance with the layer design. In normal cases, it is preferably 150 to 350 ° C., more preferably 160 to 320 ° C., and most preferably 180 to 300 ° C. Is desirable.

  The above-mentioned ranges can be mentioned as the desirable numerical ranges of the conductive substrate temperature and gas pressure for forming the photoconductive layer, but the conditions are not usually determined separately, but electrophotography having desired characteristics. It is desirable to determine an optimum value based on mutual and organic relevance in order to form a photoreceptor.

<Surface layer>
In the present invention, an a-Si surface layer can be formed on the photoconductive layer formed on the conductive substrate. This surface layer has a free surface and is provided to achieve the object of the present invention mainly in moisture resistance, continuous repeated use characteristics, electrical pressure resistance, use environment characteristics, and durability.

  Further, since each of the amorphous materials forming the photoconductive layer and the surface layer constituting the light receiving layer has a common component called silicon atoms, chemical stability can be ensured at the laminated interface. Well made.

  The surface layer can be made of any material of the a-Si type, but includes, for example, a-Si (a-SiC) containing hydrogen atoms (H) and / or halogen atoms (X) and further containing carbon atoms. : (Also denoted as (H, X)), a hydrogen atom (H) and / or a halogen atom (X), and further a nitrogen atom-containing a-Si (a-SiN: also denoted as (H, X)) ) And the like are preferably used. A material such as a-C (also represented as aC: (H, X)) containing a hydrogen atom (H) and / or a halogen atom (X) as a base is also preferably used.

  The layer thickness of the surface layer is preferably 0.01 to 3 μm, more preferably 0.05 to 2 μm, and still more preferably 0.1 to 1 μm. If the layer thickness is less than 0.01 μm, the surface layer may be lost due to wear or the like during use of the electrophotographic photosensitive member, and if it exceeds 3 μm, the residual potential may increase and the electrophotographic characteristics may deteriorate. is there.

  Furthermore, it is also possible to provide a blocking layer (lower surface layer) in which the content of one or more atoms of carbon atoms, oxygen atoms and nitrogen atoms is reduced from the surface layer between the photoconductive layer and the surface layer. This is effective for further improving the characteristics.

  Further, the interface between the surface layer and the photoconductive layer may be continuously changed so that the content of one or more atoms in the surface layer decreases toward the photoconductive layer. As a result, the adhesion between the surface layer and the photoconductive layer can be improved, and the influence of interference due to reflection of light at the interface can be further reduced.

<Lower charge injection blocking layer>
In the electrophotographic photosensitive member of the present invention, it is more effective to provide a lower charge injection blocking layer that functions to block charge injection from the conductive substrate side between the conductive substrate and the photoconductive layer. is there. That is, the lower charge injection blocking layer has a function of blocking charge injection from the conductive substrate side to the photoconductive layer side when the photoreceptive layer is subjected to charging treatment of a certain polarity on its free surface, Such a function is not exhibited when a reverse polarity charging process is performed, and so-called polarity dependency is exhibited.

  In order to provide such a function, the lower charge injection blocking layer contains a relatively large number of atoms for controlling conductivity compared to the photoconductive layer.

  The atoms controlling the conductivity contained in the lower charge injection blocking layer may be uniformly distributed in the layer, or may be contained in a non-uniformly distributed state in the layer thickness direction. good.

  When the distribution concentration is not uniform, it is preferable to contain it so as to be distributed in a large amount on the conductive substrate side.

  However, in any case, in the in-plane direction parallel to the surface of the conductive substrate, it is necessary to contain in a uniform distribution from the viewpoint of uniforming the characteristics in the in-plane direction.

  Group 13 atoms and Group 15 atoms can be used as the atoms for controlling the conductivity contained in the lower charge injection blocking layer.

  Further, the lower charge injection blocking layer contains at least one of carbon atom, nitrogen atom and oxygen atom, thereby improving adhesion between the lower charge injection blocking layer and another layer provided in direct contact with the lower charge injection blocking layer. It can be improved.

  One or more atoms of carbon atom, nitrogen atom and oxygen atom contained in the lower charge injection blocking layer may be uniformly distributed in the layer, or a portion which is contained in a non-uniformly distributed state There may be. However, in any case, in the in-plane direction parallel to the surface of the conductive substrate, it is necessary to contain in a uniform distribution from the viewpoint of uniforming the characteristics in the in-plane direction.

  The layer thickness of the lower charge injection blocking layer is preferably 0.1 to 10 μm, more preferably 0.3 to 5 μm, and still more preferably 0.5 from the viewpoints of obtaining desired electrophotographic characteristics and economic effects. ˜3 μm. When the layer thickness is less than 0.1 μm, the ability to prevent the injection of charges from the conductive substrate may be insufficient, and sufficient charging ability may not be obtained. On the other hand, even if it is thicker than 5 μm, the manufacturing cost may be increased by extending the manufacturing time rather than substantially improving the electrophotographic characteristics.

<Upper charge injection blocking layer>
In the electrophotographic photosensitive member of the present invention, it is effective to provide an upper charge injection blocking layer according to the charge polarity such as positive charge or negative charge.

  The upper charge injection blocking layer prevents injection of charges from the upper part, particularly in a negatively charged electrophotographic photosensitive member, and improves the charging ability, and a large amount of photocarriers are generated by irradiation with strong exposure. It also plays a role of preventing the so-called EV flow, that is, the image flow at the time of strong exposure in which the character portion is blurred due to the phenomenon of flowing into a portion that easily moves.

  The upper charge injection blocking layer of the present invention contains a desired amount of group 13 atoms and group 15 atoms in a non-single-crystal silicon film having carbon atoms and silicon atoms as base materials, so that the charge polarity is opposite to the charged polarity. It is preferable to adjust to an optimum resistance value that does not flow laterally while passing the carrier.

  The upper charge injection blocking layer may be any material as long as it is an a-Si-based material. For example, the upper charge injection blocking layer contains a hydrogen atom (H) and / or a halogen atom (X), and further contains a carbon atom. a-SiC: (H, X) is preferred.

  The upper charge injection blocking layer contains a relatively large amount of atoms that control conductivity as compared to the photoconductive layer. The atoms controlling the conductivity contained in the upper charge injection blocking layer may be distributed uniformly in the layer, or there may be a portion that is included in a non-uniform distribution in the layer thickness direction. good.

  When the distribution concentration is not uniform, it is preferable to contain it so as to be distributed in a large amount on the surface layer side. There may be a portion containing a non-uniform distribution state in the layer thickness direction.

  However, in any case, it is necessary from the point of achieving uniform characteristics in the in-screen direction that it is contained in a uniform distribution in the in-plane direction parallel to the surface of the conductive substrate.

  The layer thickness of the upper charge injection blocking layer may be determined by comprehensive judgment based on the layer thicknesses of the photoconductive layer and the surface layer and the required electrophotographic characteristics. The design is usually from 0.01 μm to 0.5 μm so that the ability to prevent charge injection from the surface is fully exhibited and the image quality is not affected.

"A-Si photoconductor manufacturing apparatus according to the present invention"
Next, an example of the electrophotographic photoreceptor manufacturing apparatus and the deposited layer forming method according to the present invention will be described in detail.

  FIG. 3 is a schematic configuration diagram showing an example of an electrophotographic photoreceptor manufacturing apparatus by a high-frequency plasma CVD method (also abbreviated as RF-PCVD) using an RF band as a power supply frequency. The configuration of the manufacturing apparatus shown in FIG. 3 is as follows.

  This apparatus is roughly divided into a deposition apparatus 3100, a source gas supply apparatus 3200, and an exhaust apparatus (not shown) for reducing the pressure inside the reaction vessel 3111. A cylindrical conductive substrate 3112, a substrate heating heater 3113, and a source gas introduction pipe 3114 are installed in a reaction vessel 3111 in the deposition apparatus 3100, and a high-frequency matching box 3115 is further connected.

The source gas supply device 3200 includes source gas cylinders 3221 to 3226 such as SiH ₄ , NO, H ₂ , CH ₄ , B ₂ H ₆ , and PH ₃ , valves 3231 to 3236, 3241 to 3246, 3251 to 3256, and a mass flow controller 3211. ˜3216, each source gas cylinder is connected to a gas introduction pipe 3114 in the reaction vessel 3111 via an auxiliary valve 3260.

  Formation of the deposited layer using this apparatus can be performed as follows, for example.

  First, the cylindrical conductive substrate 3112 is installed in the reaction vessel 3111, and the inside of the reaction vessel 3111 is evacuated by an unillustrated exhaust device (for example, a vacuum pump). Subsequently, the cylindrical conductive substrate 3112 is controlled to a desired temperature by the substrate heating heater 3113.

  In order to flow the deposition layer forming source gas into the reaction vessel 3111, it is confirmed that the source gas cylinder valve 3231-2236 and the reaction vessel leak valve 3117 are closed, and the gas inflow valve 3241-3246, gas outflow After confirming that the valves 3251 to 3256 and the auxiliary valve 3260 are opened, first, the main exhaust valve 3118 is opened to exhaust the reaction vessel 3111 and the gas pipe 3116.

  Next, when the reading of the vacuum gauge 3119 becomes about 0.1 Pa or less, the auxiliary valve 3260 and the gas outflow valves 3251 to 3256 are closed.

  Thereafter, each gas is introduced from the source gas cylinders 3221 to 3226 by opening the source gas cylinder valves 3231 to 2236, and each gas pressure is adjusted to 0.2 MPa by the pressure regulators 3261 to 3266. Next, the gas inflow valves 3241 to 3246 are gradually opened to introduce each gas into the mass flow controllers 3211 to 2216.

  After the preparation for film formation is completed as described above, each layer is formed according to the following procedure.

  When the cylindrical conductive substrate 3112 reaches a predetermined temperature, necessary ones of the gas outflow valves 3251 to 3256 and the auxiliary valve 3260 are gradually opened, and a predetermined gas is supplied from the gas cylinders 3221 to 3266 through the gas introduction pipe 3114. Into the reaction vessel 3111.

Next, each raw material gas is adjusted by the mass flow controllers 3211 to 3216 so as to have a predetermined flow rate. At that time, the pressure in the reaction vessel 3111 is 1 × 10 3.
The opening of the main exhaust valve 3118 is adjusted while looking at the vacuum gauge 3119 so as to be a predetermined pressure of Pa or less. When the internal pressure is stabilized, an RF power source (not shown) having a frequency of 13.56 MHz is set to a desired power, and RF power is introduced into the reaction vessel 3111 through the high-frequency matching box 3115 to cause glow discharge. The source gas introduced into the reaction vessel is decomposed by this discharge energy, and a deposited layer mainly composed of predetermined silicon is formed on the cylindrical conductive substrate 3112. After the formation of the desired film thickness, the supply of RF power is stopped, the outflow valve is closed, the gas flow into the reaction vessel is stopped, and the formation of the deposited layer is completed.

  By repeating the same operation a plurality of times, a desired multilayered light-receiving layer is formed.

  It goes without saying that all the gas outflow valves other than the necessary gas are closed when forming each layer, and each gas is transferred into the reaction vessel 3111 from the gas outflow valves 3251 to 256 in the reaction vessel 3111. In order to avoid remaining in the pipe, the gas outlet valves 3251 to 3256 are closed, the auxiliary valve 3260 is opened, the main exhaust valve 3118 is fully opened, and the system is once exhausted to a high vacuum as necessary. Do it.

  In order to make the film formation uniform, it is also effective to rotate the cylindrical conductive substrate 3112 at a predetermined speed by a driving device (not shown) during the layer formation.

  Furthermore, it goes without saying that the gas species and valve operations described above are changed according to the manufacturing conditions of each layer.

  The heating method of the conductive substrate may be a heating element having a vacuum specification, more specifically, an electric resistance heating element such as a sheathed heater, a plate heater, a ceramic heater, a halogen lamp, an infrared lamp, etc. And heat generating lamps using a heat exchanging means using a heat emitting lamp as a heating medium, liquid, gas or the like. As the surface material of the heating means, metals such as stainless steel, nickel, aluminum, and copper, ceramics, heat resistant polymer resin, and the like can be used.

  In addition to this, there is used a method in which a container dedicated to heating is provided in addition to the reaction container, and after heating, the conductive substrate is transported in the reaction container in a vacuum.

  Further, FIG. 4 is a schematic configuration diagram showing an example of an electrophotographic photosensitive member manufacturing apparatus by a high-frequency plasma CVD method using a VHF band as a power supply frequency (abbreviated as VHF-PCVD). In this VHF-PCVD, it becomes possible to simultaneously produce a large number of photoconductors, shorten the production time, and improve the gas utilization efficiency, thereby greatly improving the production efficiency.

  This manufacturing apparatus includes a reaction vessel 402 that can contain at least a cylindrical conductive substrate 401, a source gas introduction pipe 417 for supplying a source gas into the reaction vessel 402, and electric power for decomposing the source gas. A deposition apparatus 400 comprising a cathode 414 for introducing gas, a source gas supply apparatus 404 for supplying a source gas into the reaction container 402, an exhaust system 405 for exhausting the reaction container 402, and a power supply for supplying power to the cathode 414 Device 406.

  First, the cylindrical conductive substrate 401 is installed in the reaction vessel 402, the inside of the reaction vessel 402 is evacuated by the exhaust pump 407 through the exhaust port 419, and after the exhaust is completed to a desired degree of vacuum, an inert gas, For example, He gas or Ar gas is supplied into the reaction vessel 402 at a predetermined flow rate by a mass flow controller in the source gas supply device 404. The inside of the reaction vessel 402 is controlled to a desired pressure by adjusting the exhaust speed of the exhaust pump 407. After the internal pressure of the reaction vessel 402 is set to a desired pressure, the cylindrical conductive substrate 401 is heated to a desired temperature by the substrate heating heater 403. During the formation of the deposited layer, the desired temperature necessary for forming the deposited layer is maintained.

After the heating step is completed by the above procedure, a deposited layer forming step is subsequently performed. After the inert gas in the reaction vessel 402 is exhausted by the exhaust pump 407, the exhaust valve 408 is closed, the main exhaust valve 409 is opened, the throttle valve 410 is fully opened, and the reaction is performed by the oil diffusion pump 411 and the rotary pump 412. The inside of the container 402 is evacuated to a vacuum degree of 1 × 10 ⁻³ Pa, for example. Subsequently, each source gas is supplied into the reaction vessel 402 at a predetermined flow rate by a source gas supply device 404 by a mass flow controller installed in each supply pipe. By adjusting the opening degree of the throttle valve 410 and adjusting the exhaust speed, the internal pressure of the reaction vessel 402 is controlled to a desired pressure. When the internal pressure of the reaction vessel 402 is stabilized, power is supplied from the high-frequency power source 413 to the cathode 414 via the matching box 415 to cause glow discharge in the reaction vessel 402. With this discharge energy, the source gas introduced into the reaction vessel 402 is decomposed, and a predetermined deposition layer is formed on the cylindrical conductive substrate 401.

  In order to improve the uniformity of the deposited layer in the circumferential direction of the substrate, a method of rotating the substrate 401 at a predetermined speed by the motor 416 via the drive unit 418 during the formation of the deposited layer is effective. The unevenness of the Si photosensitive member in the circumferential direction can be easily reduced within an allowable range. Thus, when the deposited layer reaches a desired film thickness, the supply of power applied to the cathode 414 is stopped, and the supply of the source gas from the source gas supply unit 404 is stopped to finish the formation of the deposited layer.

  By repeating the same operation a plurality of times, it becomes possible to form a deposited layer having a multilayer structure.

“Electrophotographic photoconductor surface polishing apparatus according to the present invention”
In the present invention, after the production of the a-Si photosensitive member, the polishing process is performed and then the inspection process is performed. In order to achieve a good image formation at the time of the inspection, a good image formation on the market is achieved. It is preferable also in maintaining. By carrying out the polishing step, the spherical protrusions that protrude from the surface of the normal part due to abnormal growth can be polished to substantially the same height as the normal part. By doing so, it is possible to prevent the cleaning blade installed in the cleaner unit from being damaged when mounted on the image forming apparatus, and to suppress the occurrence of defective cleaning.

  Hereinafter, an example of an electrophotographic photoreceptor surface polishing apparatus suitable for the present invention will be described in detail.

  FIG. 6 is a schematic configuration diagram showing an example of an electrophotographic photosensitive member surface polishing apparatus. In FIG. 6, 600 is an a-Si photosensitive member, 601 is an elastic support mechanism, specifically, a pneumatic holder. In this experiment, a pneumatic holder made by Bridgestone (trade name: air pick, model number: PO45TCA * 820) is used. It was. 603 is a polishing tape, 602 is a pressure elastic roller for winding the polishing tape 603 and pressing it against the a-Si photosensitive member 600, 604 is a feed roll, 605 is a take-up roll, and 606 and 607 are quantitative feeds, respectively. Roll, capstan roller.

  The pressure elastic roller 602 is created by forming rubber as a flexible member on a cored bar. The rubber is made of a material such as neoprene (registered trademark) rubber or silicon rubber, and preferably has a JIS rubber hardness of 20 to 80, and more preferably a JIS rubber hardness of 30 to 60.

  Further, the shape of the pressure elastic roller 602 is preferably such that the diameter of the central part is thicker than both ends in order to perform uniform processing in the direction of the photoreceptor bus, and the difference in diameter is 0.01 to 0.6 mm. 0.02-0.4 mm is suitable.

Furthermore, the pressure elastic roller 602 is applied to the rotating photosensitive member 600 by 0.5 to 25 kgf / cm 2.
More preferably, the surface of the photoreceptor is polished by feeding a polishing tape 603 while applying pressure of ¹ to 10 kgf / cm ² .

  The rotational speed of the photoconductor may be appropriately adjusted in consideration of the surface properties of the photoconductor and the occurrence of polishing scratches, but is preferably 10 to 500 rpm, more preferably 20 to 200 rpm.

The polishing tape 603 is preferably a so-called lapping tape, and the abrasive grains are silicon carbide (SiC), aluminum oxide (Al ₂ O ₃ ), α iron oxide (Fe ₂ O ₃ ), chromium oxide (Cr ₂ O _3). ), Diamond (C), silica (SiO ₂ ), and the like. The grain size of the abrasive grains may be appropriately selected in consideration of the desired surface roughness of the photoreceptor and the polishing time, but is preferably 0.1 to 100 μm, more preferably 1 to 20 μm.

  The polishing tape 603 is a generally well-known coating method such as a doctor blade (knife edge) coating method, a dip coating method, an air knife coating method, a curtain coating method, a wire bar coating method, a gravure coating method, an extrusion coating method, etc. It is possible to apply by.

  Here, a wrapping tape LT-C2000 (abrasive grains: silicon carbide (SiC), particle diameter: 6 μm, coating method: doctor blade (knife edge) coating method) manufactured by Fuji Photo Film Co., Ltd. was used.

  The feed rate of the polishing tape may be appropriately adjusted in consideration of the surface property of the photoreceptor, the occurrence of polishing scratches, the processing cost, etc., but is preferably 1 to 500 mm / min, more preferably 10 to 100 mm / min.

  The polishing process time may be adjusted as appropriate after confirming that the height of the spherical protrusion can be polished to substantially the same height as that of the normal part, but it is about 10 seconds to 30 minutes, and further about 30 seconds to 3 minutes. Is preferred.

“Image Forming Apparatus According to the Present Invention”
FIG. 5 shows an example of an image forming apparatus according to the present invention in which an a-Si photoconductor is mounted in an inspection process for evaluating image defects of the photoconductor. The apparatus of this example is suitable when a cylindrical electrophotographic photosensitive member is used. However, the image forming apparatus of the present invention is not limited to this example, and the shape of the photosensitive member is an endless belt. It may be as desired. The apparatus of this example is a digital image forming apparatus, but may be an analog image forming apparatus.

  In the image forming apparatus 500 of FIG. 5, reference numeral 501 denotes an electrophotographic photosensitive member, and reference numeral 502 denotes a primary charger that charges the photosensitive member 501 for forming an electrostatic latent image. Reference numeral 503 denotes an electrostatic latent image forming unit (exposure device). As a light source for exposure L, a halogen light source or a light source mainly having a single wavelength is used. Reference numeral 504 denotes a developing device for supplying a developer (toner) to the photoreceptor 501 on which the electrostatic latent image is formed. Reference numeral 505 separates the transfer material after transferring the toner on the surface of the photoreceptor to the transfer material. This is a transfer / separation charger.

  Reference numeral 506 denotes a cleaner for purifying the surface of the photoreceptor. In this example, in order to effectively remove the surface of the photoconductor, the surface of the photoconductor is cleaned using the elastic roller 5061 and the cleaning blade 5062 as described above, but only one of them may be used.

  Reference numeral 507 denotes a neutralizing light source for neutralizing the surface of the photoreceptor in preparation for the next copying operation, 510 a transfer material such as paper, and 509 a registration roller for feeding the transfer material.

  Using such an apparatus, a copy image is formed as follows, for example. First, the electrophotographic photoreceptor 501 is rotated at a predetermined speed in the direction indicated by the arrow X, and the surface of the photoreceptor 501 is uniformly charged using the primary charger 502. Next, image exposure L is performed on the surface of the charged photoconductor 501 to form an electrostatic latent image of the image on the surface of the photoconductor 501. Then, when the electrostatic latent image on the surface of the photoconductor 501 is passed through the installation portion of the developing device 504, toner is supplied to the surface of the photoconductor 501 by the developing device 504, and the electrostatic latent image is generated. The toner image is developed (developed) as an image, and the toner image reaches the installation portion of the transfer / separation charger 505 as the photosensitive member 501 rotates. Here, the toner image is transferred to the transfer material 510 sent by the registration roller 509. Transcribed.

  After the transfer is completed, residual toner is removed from the surface of the electrophotographic photosensitive member 501 by the cleaner 506 in order to prepare for the next copying process, and further, the charge is removed by the charge removing light source 507 so that the potential of the surface becomes zero or almost zero. One copy process is completed.

  Furthermore, in the method for manufacturing an a-Si photosensitive member according to the present invention, in order to perform the inspection process by appropriately controlling the humidity environment of the image forming apparatus main body or the developing unit, as shown in FIG. The image forming apparatus 700 is preferably installed in an air conditioning booth 702 in which the apparatus 701 is connected by a connection duct 703. By using such an air conditioning booth, it is possible to easily and accurately control the humidity even with respect to the heat generated by the image forming apparatus itself, which is a disturbance factor of the humidity environment, and the effects of the present invention can be obtained. It becomes.

  In another embodiment of the present invention, only the developing device 504 detachable from the image forming apparatus is left in an air conditioning booth that is smaller and easy to control humidity, and is taken out only during the inspection process to form an image. It is preferable to perform the inspection by installing the apparatus. By doing so, the effect of the present invention can be obtained more easily.

  Hereinafter, the present invention will be described in detail based on examples and comparative examples.

  The following examples are examples of the best mode of the present invention, but the present invention is not limited to these examples.

  According to the above procedure using the plasma processing apparatus shown in FIG. 4, the charge injection blocking layer, the first and second photoconductive layers, and the surface layer shown in FIG. Thirty positively charged a-Si photoconductors with a diameter of 80 mm were produced.

  “200 → 30” in the manufacturing conditions shown in Table 1 indicates that the gas flow rate is continuously changed from 200 mL / min (normal) to 30 ml / min (normal).

作製したａ−Ｓｉ感光体を、図６に示した電子写真感光体表面研磨装置を用いて研磨処理を実施した。

The produced a-Si photosensitive member was subjected to polishing using the electrophotographic photosensitive member surface polishing apparatus shown in FIG.

  Thereafter, in the air conditioning booth to which the humidity control air conditioner shown in FIG. 7 is connected, using the image forming apparatus shown in FIG. Conducted and evaluated.

  Specifically, a solid black image was output using a Canon digital image forming apparatus iR-6000 (pre-exposure 660 nm LED array, image exposure 655 nm laser, process speed 265 mm / sec), and image defects caused by spherical protrusions were evaluated. Was performed by the following method.

  First, the main charger current was adjusted so that the dark portion potential at the developing device position had a predetermined value, and then the image exposure intensity was adjusted so that the bright portion potential at the developing device position had a predetermined value. Next, the development bias is adjusted to output a solid black image having an average transmission density of 2.0 on A3 paper, and a diameter of 0 recognized within a length of about 251 mm (image area corresponding to one rotation of the photoreceptor). The number of white spots of .05 mm or more was counted and evaluated based on the number.

  Further, the humidity environment of the air conditioning booth was appropriately controlled to change the temperature at a constant 25 ° C. and the humidity within a range of 5 to 90%. FIG. 2A shows the humidity dependency evaluation result of the number of image defects of the three a-Si photosensitive members.

  Here, the number of image defects was expressed as a value normalized with the value at a humidity of 90% as 100. From the result of FIG. 2A, it was found that the humidity range in the critical region where the number of image defects increases depending on the humidity is 20 to 60%.

  Next, as an initial evaluation of 30 a-Si photoconductors produced, a solid black image was output in an air conditioning booth controlled to a humidity of 70% higher than the humidity range of the critical region, and image defects of the photoconductor were evaluated. Carried out. Image defects were evaluated according to the number and diameter of image defects in the entire area of the solid black image of A3, good, slightly good, no practical problem, and practical problem. Table 2 shows the initial evaluation results.

  Furthermore, these 30 photoreceptors were mounted on an iR-6000, and 250,000 sheets were passed through using a test chart with a printing rate of 7% under a high temperature and high humidity environment of 30 ° C. and 80%. . After the end of paper passing, as in the initial evaluation, a solid black image was output in an air conditioning booth controlled to a humidity of 70% to evaluate image defects on the photoreceptor. The evaluation results after durability are also shown in Table 2.

表２において、耐久後評価で実用上問題ありと評価された３本の感光体は、初期評価で実用上問題ありと評価された感光体と同一であった。従って、感光体の検査工程においては、
初期評価で実用上問題ありと評価された３本の感光体のみを出荷品から除外しておけば充分であることが判明した。

In Table 2, the three photoconductors evaluated as having practical problems in the post-endurance evaluation were the same as the photoconductors evaluated as having practical problems in the initial evaluation. Therefore, in the photoreceptor inspection process,
It has been found that it is sufficient to exclude only the three photoconductors evaluated as having practical problems in the initial evaluation from the shipment.

<Comparative Example 1>
The same 30 photoconductors as in Example 1 were mounted on the iR-6000, and as an initial evaluation, a solid black image was output without controlling the humidity environment of the air conditioning booth, and image defects were evaluated. At this time, the humidity in the air conditioning booth was 40%. Table 3 shows the initial evaluation results.

  Furthermore, the post-endurance evaluation results performed in Example 1 are also shown in Table 3.

表３において、耐久後評価で実用上問題ありと評価された３本の感光体の内の２本は、初期評価で実用上問題ありと評価された感光体と同一でなく、実用上問題なしに含まれていた。従って、検査工程における画像品質上の許容レベルをやや良好以上に設定しなければならないことが分かり、初期評価で実用上問題あり及び実用上問題なしと評価された６本の感光体を出荷品から除外しておく必要があることが判明した。実施例１及び比較例１の結果により、本発明による検査工程を実施することにより、検査工程での不良品数を最小にする効果があることが判った。

In Table 3, two of the three photoconductors evaluated as having practical problems in the post-endurance evaluation are not the same as the photoconductor evaluated as having practical problems in the initial evaluation, and there are no practical problems. It was included in. Therefore, it is understood that the acceptable level for image quality in the inspection process must be set slightly higher or better, and six photoreceptors evaluated as having practical problems and no practical problems in the initial evaluation from the shipment. It turns out that it needs to be excluded. From the results of Example 1 and Comparative Example 1, it has been found that performing the inspection process according to the present invention has the effect of minimizing the number of defective products in the inspection process.

  Next, based on the humidity-dependent evaluation result of the number of image defects in FIG. 2A performed in Example 1, the humidity environment is 70% higher than the humidity range in the critical region where the number of image defects increases depending on the humidity. Using the developing device that was always left below, the same 30 photoreceptors as in Example 1 were mounted on iR-6000, and image defects were evaluated as an initial evaluation. Here, without controlling the humidity environment of the air conditioning booth, the developer was always left in a small air conditioning booth where the humidity was controlled to 70%, and was taken out and used only during image formation. At this time, the humidity in the air conditioning booth was 40%. Table 4 shows the initial evaluation results.

  Furthermore, the evaluation results after durability carried out in Example 1 are also shown in Table 4.

表４において、耐久後評価で実用上問題ありと評価された３本の感光体は、初期評価で実用上問題ありと評価された感光体と同一であった。従って、感光体の検査工程においては、
初期評価で実用上問題ありと評価された３本の感光体のみを出荷品から除外しておけば充分であることが判明し、本発明による検査工程を実施することにより、検査工程での不良品数を最小にする効果があることが判った。

In Table 4, the three photoconductors evaluated as having practical problems in the post-endurance evaluation were the same as the photoconductors evaluated as having practical problems in the initial evaluation. Therefore, in the photoreceptor inspection process,
It turns out that it is sufficient to exclude only the three photoconductors evaluated as having practical problems in the initial evaluation from the shipment, and by performing the inspection process according to the present invention, defects in the inspection process It has been found that there is an effect of minimizing the number of products.

  Next, the 18 a-Si photoconductors produced in the same manner as in Example 1 except that the production conditions shown in Table 5 were used were subjected to a polishing treatment, and 3 of the produced a-Si photoconductors. The book was extracted to evaluate image defects caused by the spherical protrusions.

実施例１と同じくｉＲ−６０００を用い、平均透過濃度が２．０のベタ黒画像をＡ３用紙で出力し、約２５１ｍｍの長さ（感光体１回転分に相当する画像域）の範囲に認められる白点を任意にピックアップし、その画像欠陥の直径の平均値により評価した。

As in Example 1, iR-6000 was used, and a solid black image with an average transmission density of 2.0 was output on A3 paper, and was recognized within a range of about 251 mm in length (image area corresponding to one rotation of the photoreceptor). The white spots to be obtained were arbitrarily picked up and evaluated by the average value of the diameters of the image defects.

  Further, the humidity environment of the air conditioning booth was appropriately controlled to change the temperature at a constant 25 ° C. and the humidity within a range of 5 to 90%. FIG. 2B shows the humidity dependency evaluation results of the image defect diameters of the three a-Si photosensitive members.

  Here, the image defect diameter is expressed as a value normalized with the value at a humidity of 90% as 100. From the result of FIG. 2B, it was found that the humidity range of the critical region where the image defect diameter increases depending on the humidity is 20 to 55%.

  Next, as an initial evaluation of the 18 a-Si photoconductors produced, a solid black image was output in an air conditioning booth controlled to a humidity of 60% higher than the critical humidity range, and image defects of the photoconductor were evaluated. did. Image defects were evaluated according to the number and diameter of image defects in the entire area of the solid black image of A3, good, slightly good, no practical problem, and practical problem. Table 6 shows the initial evaluation results.

  Furthermore, the 18 photoconductors were mounted on the iR-6000, and 250,000 sheets were passed through a test chart with a printing rate of 7% under a high temperature and high humidity environment of 30 ° C. and 80%. . After the end of paper passing, as in the initial evaluation, a solid black image was output in an air conditioning booth controlled to a humidity of 70% to evaluate image defects on the photoreceptor. The evaluation results after durability are also shown in Table 6.

表６において、耐久後評価で実用上問題ありと評価された２本の感光体は、初期評価で実用上問題ありと評価された感光体と同一であった。従って、感光体の検査工程においては、
初期評価で実用上問題ありと評価された２本の感光体のみを出荷品から除外しておけば充分であることが判明した。

In Table 6, the two photoconductors evaluated as having practical problems in the post-endurance evaluation were the same as the photoconductors evaluated as having practical problems in the initial evaluation. Therefore, in the photoreceptor inspection process,
It has been found that it is sufficient to exclude only the two photoconductors evaluated as having practical problems in the initial evaluation from the shipment.

<Comparative example 2>
The same 18 photoconductors as in Example 3 were mounted on the iR-6000, and as an initial evaluation, a solid black image was output without controlling the humidity environment of the air conditioning booth, and image defects were evaluated. At this time, the humidity in the air conditioning booth was 40%. Table 7 shows the initial evaluation results.

  Furthermore, the post-endurance evaluation results performed in Example 3 are also shown in Table 7.

表７において、耐久後評価で実用上問題ありと評価された２本の感光体の内の１本は、初期評価で実用上問題ありと評価された感光体と同一でなく、実用上問題なしに含まれていた。従って、検査工程における画像品質上の許容レベルをやや良好以上に設定しなければならないことが分かり、初期評価で実用上問題あり及び実用上問題なしと評価された５本の感光体を出荷品から除外しておく必要があることが判明した。実施例３及び比較例２の結果により、本発明による検査工程を実施することにより、検査工程での不良品数を最小にする効果が有ることが判った。

In Table 7, one of the two photoconductors evaluated as having practical problems in the post-endurance evaluation is not the same as the photoconductor evaluated as having practical problems in the initial evaluation, and there is no practical problem. It was included in. Therefore, it is understood that the acceptable level for image quality in the inspection process must be set to be slightly better or better, and five photoreceptors evaluated as having practical problems and practical problems in the initial evaluation from the shipped products. It turns out that it needs to be excluded. From the results of Example 3 and Comparative Example 2, it was found that performing the inspection process according to the present invention has the effect of minimizing the number of defective products in the inspection process.

  Next, based on the humidity-dependent evaluation result of the image defect diameter of FIG. 2B performed in Example 3, a humidity environment of 60% higher than the humidity range in the critical region where the image defect diameter increases depending on the humidity. The same 18 photosensitive members as in Example 3 were mounted on iR-6000 using a developing device that was always left under, and image defects were evaluated as an initial evaluation. Here, without controlling the humidity environment of the air conditioning booth, it was always left in a small air conditioning booth in which only the developing device was controlled to 60% humidity, and was taken out and used only during image formation. At this time, the humidity in the air conditioning booth was 30%. Table 8 shows the initial evaluation results.

  Furthermore, the post-endurance evaluation results performed in Example 3 are also shown in Table 8.

表８において、耐久後評価で実用上問題ありと評価された２本の感光体は、初期評価で実用上問題ありと評価された感光体と同一であった。従って感光体の検査工程においては、
初期評価で実用上問題ありと評価された２本の感光体のみを出荷品から除外しておけば充分であることが判明し、本発明による検査工程を実施することにより、検査工程での不良品数を最小にする効果があることが分かった。

In Table 8, the two photoconductors evaluated as having practical problems in the post-endurance evaluation were the same as the photoconductors evaluated as having practical problems in the initial evaluation. Therefore, in the photoconductor inspection process,
It turns out that it is sufficient to exclude only the two photoconductors evaluated as having practical problems in the initial evaluation from the shipment, and by performing the inspection process according to the present invention, defects in the inspection process It was found that there is an effect to minimize the number of products.

1 is a schematic cross-sectional view schematically showing a layer configuration of an electrophotographic photoreceptor according to the present invention. (A) is a figure which shows an example of the humidity dependence evaluation result of the number of image defects which concerns on this invention, (b) is a figure which shows an example of the humidity dependence evaluation result of the image defect diameter which concerns on this invention. It is a typical block diagram which shows an example of the electrophotographic photoreceptor manufacturing apparatus by RF-PCVD which concerns on this invention. It is a typical block diagram which shows an example of the electrophotographic photoreceptor manufacturing apparatus by VHF-PCVD which concerns on this invention. 1 is a schematic configuration diagram showing an example of a digital image forming apparatus equipped with an electrophotographic photosensitive member according to the present invention. It is a typical block diagram which shows an example of the electrophotographic photoreceptor surface polishing apparatus which concerns on this invention. It is a typical block diagram which shows an example of the booth for an air conditioning which connected the air conditioner for humidity control which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Electrophotographic photoreceptor 101 Conductive substrate 102 Photoreceptive layer 103 Photoconductive layer 1031 First layer region 1032 Second layer region 104 Surface layer 105 Lower charge injection blocking layer 106 Upper charge injection blocking layer 3100 Deposition device 3111 Reaction vessel 3112 Cylindrical conductive substrate 3113 Heater for substrate heating 3114 Material gas introduction tube 3115 Matching box 3116 Material gas piping 3117 Reaction vessel leak valve 3118 Main exhaust valve 3119 Vacuum gauge 3200 Material gas supply device 3211-3216 Mass flow controller 3221-3226 Material gas cylinder 3231 to 2236 Raw material gas cylinder valve 3241 to 3246 Gas inflow valve 3251 to 3256 Gas outflow valve 3260 Auxiliary valve 3261 to 3266 Pressure regulator 40 Deposition device 401 Cylindrical conductive substrate 402 Reaction vessel 403 Heater for substrate heating 404 Raw material gas supply device 405 Exhaust system 406 Power supply device 407 Exhaust pump 408 Exhaust valve 409 Main exhaust valve 410 Throttle valve 411 Oil diffusion pump 412 Rotary pump 413 High frequency Power source 414 Cathode 415 Matching box 416 Motor 417 Source gas introduction pipe 418 Drive unit 419 Exhaust port 500 Image forming apparatus 501 Electrophotographic photosensitive member 502 Primary charger 503 Electrostatic latent image forming means (exposure apparatus)
504 Developing device 505 Transfer / separation charging device 506 Cleaner 5061 Elastic roller 5062 Cleaning blade 507 Static elimination light source 508 Fixing device 509 Registration roller 510 Transfer material 600 a-Si photosensitive member 601 Elastic support mechanism 602 Pressure elastic roller 603 Polishing tape 604 Delivery roll 605 Take-up roll 606 Fixed feed roll 607 Capstan roller 700 Image forming apparatus 701 Humidity control air conditioner 702 Air conditioning booth 703 Connection duct

Claims (4)

In the method for producing an electrophotographic photosensitive member in which at least an amorphous silicon-based photoconductive layer is formed on a support,
An inspection process for evaluating image defects of the photoreceptor, and the inspection process is based on the humidity dependence of the number of image defects evaluated by performing image formation by changing the humidity environment in advance. The electrophotographic photosensitive member is produced in a humidity environment higher than the humidity range of the critical region that increases depending on the temperature. In the method for producing an electrophotographic photosensitive member in which at least an amorphous silicon-based photoconductive layer is formed on a support,
An inspection process for evaluating image defects of the photoreceptor, and the inspection process is based on the humidity dependence of the number of image defects evaluated by performing image formation by changing the humidity environment in advance. A method for producing an electrophotographic photosensitive member, characterized in that the method is carried out using a developing device that is always left in a humidity environment higher than the humidity range of the critical region that increases depending on the temperature. In the method for producing an electrophotographic photosensitive member in which at least an amorphous silicon-based photoconductive layer is formed on a support,
An inspection process for evaluating image defects of the photoconductor, and the inspection process is based on the humidity dependence of the image defect diameter evaluated by performing image formation by changing the humidity environment in advance. The electrophotographic photosensitive member production method is characterized in that the method is carried out in a humidity environment that is higher than a humidity range in a critical region that increases depending on humidity. In the method for producing an electrophotographic photosensitive member in which at least an amorphous silicon-based photoconductive layer is formed on a support,
An inspection process for evaluating the image defect of the photoconductor, and the inspection process is based on the humidity dependence of the diameter of the image defect evaluated by performing image formation by changing the humidity environment in advance. A method for producing an electrophotographic photosensitive member, which is carried out using a developing device that is always left in a humidity environment higher than a humidity range in a critical region that increases depending on humidity.

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