JP2015102676A - Method for processing surface of electrophotographic photoreceptor and method for manufacturing electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for processing a surface of a cylindrical electrophotographic photoreceptor for reducing an abnormal sound that generates by friction against a cleaning blade upon starting use of the electrophotographic photoreceptor, and a method for manufacturing a cylindrical electrophotographic photoreceptor having a rugged pattern on a surface thereof.SOLUTION: The method for processing a surface of an electrophotographic photoreceptor includes a step of transferring a surface pattern of a surface of a die member onto a surface of a cylindrical electrophotographic photoreceptor while rotating the electrophotographic photoreceptor. The surface of the electrophotographic photoreceptor includes: a region (A) where the surface pattern of the die member is transferred n times to the surface of the electrophotographic photoreceptor by press-contacting the die member n times; and a region (B) adjoining to the region (A), where the surface pattern is transferred n+1 times or more onto the surface of the electrophotographic photoreceptor by press-contacting the die member n+1 times or more.

Description

  The present invention relates to a surface processing method of an electrophotographic photosensitive member and a method of manufacturing an electrophotographic photosensitive member.

  An electrophotographic photosensitive member containing an organic photoconductive substance (charge generating substance) is curable on the surface layer of the electrophotographic photosensitive member for the purpose of improving the durability (such as wear resistance) of the electrophotographic photosensitive member. A technique for containing a resin is known.

  However, by improving the abrasion resistance of the electrophotographic photosensitive member, the influence on the cleaning performance and the image flow are likely to occur. The image flow is considered to be caused by an acidic gas such as ozone or nitrogen oxide generated by charging the electrophotographic photosensitive member. This acid gas deteriorates the material used for the surface layer of the electrophotographic photosensitive member, or part of the acidic gas becomes nitric acid due to moisture adsorption, and the surface of the electrophotographic photosensitive member is reduced in resistance. Is considered to be the cause. As the abrasion resistance of the electrophotographic photosensitive member becomes higher, the surface of the electrophotographic photosensitive member is less likely to be refreshed (removal of substances that cause image flow), and image flow is more likely to occur.

  The effect on cleaning performance is caused by problems such as increased friction between the surface of the electrophotographic photosensitive member and the cleaning blade, reversal and chipping of the cleaning blade, and toner slipping due to increased micro vibration. is there.

  As a technique for improving these problems, Patent Document 1 describes an electrophotographic photosensitive member having specific concave portions on the surface of the electrophotographic photosensitive member in order to improve image flow under a high temperature and high humidity environment. Patent Document 2 describes a technique relating to a manufacturing method for forming the surface shape of an electrophotographic photosensitive member with good controllability for the purpose of improving cleaning properties.

JP 2007-233355 A JP 2007-233356 A

  However, the techniques described in Patent Documents 1 and 2 tend to cause a problem that abnormal noise is caused by rubbing of the cleaning blade at the start of use of the electrophotographic photosensitive member, and there is room for improvement.

  An object of the present invention is to provide a surface processing method for a cylindrical electrophotographic photosensitive member in which abnormal noise generated at the start of use of the electrophotographic photosensitive member is reduced, and a method for manufacturing a cylindrical electrophotographic photosensitive member having an uneven surface. Is to provide.

  The above object is achieved by the present invention described below.

The present invention is a method of forming an uneven shape on the surface of a cylindrical electrophotographic photosensitive member,
The electrophotographic photosensitive member is brought into pressure contact with a plate-shaped mold member having a surface shape corresponding to the uneven shape, and the surface shape of the surface of the mold member is changed to the electrophotographic photosensitive member while rotating the electrophotographic photosensitive member. Having a process of transferring to the surface of the body,
The surface of the electrophotographic photoreceptor is
Region A in which the mold member is brought into pressure contact n times to transfer the surface shape onto the surface of the electrophotographic photosensitive member n times, and the mold member is brought into pressure contact at least n + 1 times adjacent to the region A The present invention relates to a surface processing method for a cylindrical electrophotographic photosensitive member, which has a region B in which the surface shape is transferred to the surface of the electrophotographic photosensitive member n + 1 times or more.

  Further, the present invention provides an electrophotographic photosensitive member, and has a step of forming an uneven shape on the surface of the cylindrical electrophotographic photosensitive member using the surface processing method described above. The present invention relates to a method for manufacturing a cylindrical electrophotographic photosensitive member having a shape.

  According to the present invention, a surface processing method of a cylindrical electrophotographic photosensitive member in which abnormal noise generated at the start of use of the electrophotographic photosensitive member is reduced, and a manufacturing method of a cylindrical electrophotographic photosensitive member having an uneven surface. Can be provided.

(A)-(D) is a figure which shows typically the relationship of the area | region A, the area | region B, Wb, etc. in a cylindrical electrophotographic photoreceptor. It is a figure which shows the example of the press-contact shape transcription | transfer processing apparatus for forming uneven | corrugated shape on the surface of an electrophotographic photoreceptor. It is a figure which shows the example of the electrophotographic apparatus provided with the process cartridge which has a cylindrical electrophotographic photoreceptor. It is a figure which shows a type | mold member typically.

  The surface processing method of the cylindrical electrophotographic photosensitive member of the present invention comprises rotating the electrophotographic photosensitive member by pressing and contacting the electrophotographic photosensitive member with a flat plate-shaped mold member having a surface shape corresponding to the uneven shape. And transferring the surface shape of the mold member to the surface of the electrophotographic photosensitive member. The surface of the electrophotographic photosensitive member has a region A in which the mold member is brought into pressure contact n times and the surface shape is transferred n times to the surface of the electrophotographic photosensitive member. Further, it is characterized by having a region B adjacent to the region A, in which the mold member is pressed and contacted n + 1 times or more and the surface shape is transferred to the surface of the electrophotographic photosensitive member n + 1 times or more. That is, the surface processed surface is overlapped when forming an uneven shape on the surface of the electrophotographic photosensitive member.

  As a result of the study by the present inventors, it has been found that noise generated by rubbing with the cleaning blade at the start of use of the electrophotographic photosensitive member is reduced by superimposing the surface processed surfaces. The start of use of the electrophotographic photosensitive member means a point in time when the electrophotographic photosensitive member is mounted on the main body of the electrophotographic apparatus and driving is started.

  When a flat mold member is brought into pressure contact with the surface of the electrophotographic photosensitive member to transfer the surface shape of the surface of the mold member, the surface of the electrophotographic photosensitive member where pressure contact is started by the mold member is transferred. A minute dent is generated. Due to this recess, as shown in FIG. 1 (B), a convex portion 1-2 continuous in the longitudinal direction of the electrophotographic photosensitive member is generated. Due to this convex portion, abnormal noise was generated by rubbing with the cleaning blade at the start of use of the electrophotographic photosensitive member.

  Therefore, in the present invention, the surface is processed again by superimposing the surface-processed surfaces, so that the protrusions as shown in a region B (1-3) in FIG. It is possible to deform so as to eliminate the part. This makes it possible to suppress vibrations when the cleaning blade rubs the above-described convex portions, thereby reducing abnormal noise.

  In the present invention, n is preferably 1. In this case, the region A (FIG. 1C) 1-1 is a region in which the uneven shape is formed once, and the region B (FIG. 1D) 1-4 is formed in the uneven shape twice or more. It is an area.

The length of the region B in the rotation direction of the electrophotographic photosensitive member is Wb (FIG. 1 (D) 1-4),
When the length in the rotation direction of the electrophotographic photosensitive member of the contact area between the cleaning blade as the cleaning member and the electrophotographic photosensitive member is W,
It is preferable that W and Wb satisfy the following formula (1). When the following formula (1) is satisfied, it is possible to further reduce abnormal noise.
Wb> W (1)

  About the said area | region A, area | region B, Wb and W, the transferred uneven | corrugated shape, etc., it can observe using microscopes, such as a laser microscope, an optical microscope, an electron microscope, and an atomic force microscope.

  As the laser microscope, for example, the following devices can be used.

Keyence Corporation ultra-deep shape measurement microscope VK-8550, ultra-deep shape measurement microscope VK-9000, ultra-deep shape measurement microscope VK-9500, VK-X200
Surface shape measuring system Surface Explorer SX-520DR model manufactured by Ryoka System Co., Ltd. Scanning confocal laser microscope OLS3000 manufactured by Olympus Corporation
Real color confocal microscope OPTELICS series H1200 manufactured by Lasertec Co., Ltd.

As the optical microscope, for example, the following devices can be used.
Digital microscope VHX-500, digital microscope VHX-200 manufactured by Keyence Corporation
3D digital microscope VC-7700 manufactured by OMRON Corporation

As the electron microscope, for example, the following devices can be used.
Keyence 3D Real Surface View Microscope VE-9800, 3D Real Surface View Microscope VE-8800
Scanning Electron Microscope Conventional / Variable Pressure SEM manufactured by SII NanoTechnology Co., Ltd.
Scanning electron microscope SUPERSCAN SS-550 manufactured by Shimadzu Corporation

As the atomic force microscope, for example, the following devices can be used.
KEYENCE nanoscale hybrid microscope VN-8000
Scanning Probe Microscope NanoNavi Station manufactured by SII Nano Technology Co., Ltd. Scanning Probe Microscope SPM-9600 manufactured by Shimadzu Corporation

  Region A is a region where the surface shape of the mold member has been transferred n times to the surface of the electrophotographic photosensitive member, and is a region where the concavo-convex shapes formed n times overlap and are observed. However, when n is 1, it is an area where the surface shape of the mold member is transferred once to the surface of the electrophotographic photosensitive member, and an uneven shape corresponding to the surface shape of the mold member is observed. On the other hand, the region B is a region in which the surface shape of the mold member is transferred to the surface of the electrophotographic photosensitive member n + 1 times or more, so that the uneven shape formed at the nth time and the uneven shape formed after the n + 1 time are overlapped. Is a region observed.

  The measurement of Wb may be performed at a low magnification as long as the magnification at which the surface processing start portion can be identified. When evaluating the longitudinal direction of the electrophotographic photosensitive member, a plurality of partial images may be connected using software. First, the surface of the electrophotographic photoreceptor is enlarged and observed with a microscope. For example, the surface (circumferential surface) of the cylindrical electrophotographic photosensitive member and the cross-sectional profile of the curved surface are extracted, and a curve (arc if the electrophotographic photosensitive member is cylindrical) is fitted. After correcting so that the curve becomes a straight line, the width of the start position of the surface processing and the end position of the surface processing is measured, and the minimum value of the width measured in the longitudinal direction of the electrophotographic photosensitive member is defined as Wb.

The region A and the region B are different in the formed uneven shape, and therefore the optimum setting of the cleaning blade is different. Therefore, from the viewpoint of maintaining cleaning properties, it is preferable that Wb satisfies the following formula (2).
40 mm ≧ Wb (2)
Furthermore, it is preferable to satisfy the following formula (3).
20 mm ≧ Wb ≧ 0.5 mm (3)

  The measurement of W may be performed by directly observing and measuring the length of the contact area between the cleaning blade and the electrophotographic photosensitive member in the rotation direction of the electrophotographic photosensitive member. It doesn't matter. When evaluating the longitudinal direction of the electrophotographic photosensitive member, a plurality of partial images may be connected using software. The length of the contact area between the cleaning blade and the electrophotographic photosensitive member in the rotation direction of the electrophotographic photosensitive member is measured, and the maximum length measured in the longitudinal direction of the cleaning blade is defined as W.

<Method for forming uneven shape on the surface of electrophotographic photosensitive member>
A plate-shaped mold member having a surface shape is brought into pressure contact with the surface of the electrophotographic photosensitive member, and the surface shape of the surface of the mold member is transferred to the surface of the electrophotographic photosensitive member while rotating the electrophotographic photosensitive member. An uneven shape can be formed on the surface of the electrophotographic photosensitive member.

  FIG. 2 shows an example of a pressure contact shape transfer processing apparatus for forming an uneven shape on the surface of an electrophotographic photosensitive member.

  According to the press-contact shape transfer processing apparatus shown in FIG. 2, a flat plate-shaped mold member 2- is continuously formed on the surface (circumferential surface) of the cylindrical electrophotographic photosensitive member 2-1, which is a workpiece. The mold member is moved while contacting 2 and applying pressure. As a result, the surface shape of the mold member can be transferred to the surface of the electrophotographic photosensitive member while rotating the electrophotographic photosensitive member, and an uneven shape can be formed on the surface of the electrophotographic photosensitive member 2-1.

  Examples of the material of the pressure member 2-3 include metal, metal oxide, plastic, and glass. Among these, stainless steel (SUS) is preferable from the viewpoint of mechanical strength, dimensional accuracy, and durability. The pressing member 2-3 is provided with a mold member on the upper surface thereof. Further, a predetermined pressure is applied to the surface of the electrophotographic photosensitive member 2-1 supported by the support member 2-4 by a support member (not shown) on the lower surface side and a pressure system (not shown). Can be contacted. Further, the support member 2-4 may be pressed against the pressure member 2-3 with a predetermined pressure, or the support member 2-4 and the pressure member 2-3 may be pressed against each other.

  The example shown in FIG. 2 is an example in which the surface of the electrophotographic photosensitive member 2-1 is continuously processed while being driven or driven and rotated by moving the pressing member 2-3. Further, the electrophotographic photosensitive member 2 is fixed by fixing the pressure member 2-3 and moving the support member 2-4, or by moving both the support member 2-4 and the pressure member 2-3. The surface of -1 can also be processed continuously.

  Note that the mold member 2-2 and the electrophotographic photosensitive member 2-1 may be heated from the viewpoint of efficiently performing shape transfer.

  Examples of the mold member include a metal or resin film having a surface shape, a silicon wafer surface patterned with a resist, a resin film in which fine particles are dispersed, and a resin film having a fine surface shape provided with a metal coating. Things. In addition, a mold member obtained by performing a necessary etching process after drawing a fine shape on a silicon wafer by photolithography or electron beam can also be used. Moreover, the mold member obtained by the nickel electroforming method which used as a mother die (master) what described the fine shape by laser processing etc. to resin, such as a polyimide, can also be used.

  Examples of the uneven shape on the surface of the electrophotographic photosensitive member include a shape in which cylindrical, prismatic or hemispherical convex portions are continuous, and conversely, a shape in which cylindrical, prismatic or hemispherical concave portions are continuous. Can be mentioned. In addition, a shape in which convex or concave line shapes are continuous at regular or random intervals is also exemplified. The direction of the convex or concave line shape may be the circumferential direction of the cylindrical electrophotographic photosensitive member or the rotational axis direction.

  From the viewpoint of making the pressure pressed against the electrophotographic photosensitive member uniform, it is preferable to install an elastic body between the mold member 2-2 and the pressure member 2-3.

  Next, the surface shape of the surface of the mold member will be described. The surface shape of the mold member is a shape corresponding to the uneven shape formed on the surface of the electrophotographic photosensitive member. As these surface shapes, for example, a shape in which a large number of convex portions are formed on a plane portion can be mentioned. Examples of the shape of the convex portion include a circle, an ellipse, a square, a rectangle, a triangle, a quadrangle, and a hexagon when the convex portion is viewed from above. In addition, the cross-sectional shape of the convex portion may be, for example, those having edges such as triangles, quadrilaterals, polygons, corrugations consisting of continuous curves, and some or all of the edges of triangles, quadrilaterals, polygons as curves. Deformed ones are listed.

<Configuration of process cartridge and electrophotographic apparatus>
FIG. 3 shows an example of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention.

  In FIG. 3, a cylindrical electrophotographic photosensitive member 1 is rotationally driven with a predetermined peripheral speed (process speed) in the direction of an arrow about an axis 2. The surface of the electrophotographic photosensitive member 1 is uniformly charged to a predetermined positive or negative potential by a charging unit 3 (primary charging unit: for example, a charging roller) during the rotation process. Next, the surface of the charged electrophotographic photosensitive member 1 is irradiated with exposure light (image exposure light) 4 from exposure means (image exposure means) (not shown), and an electrostatic latent image corresponding to target image information. Will be formed. The image exposure light 4 is, for example, intensity-modulated light corresponding to a time-series electric digital image signal of target image information output from image exposure means such as slit exposure or laser beam scanning exposure.

  The electrostatic latent image formed on the surface of the electrophotographic photosensitive member 1 is developed (regular development or reversal development) with a developer (toner) accommodated in the developing means 5, and toner is applied to the surface of the electrophotographic photosensitive member. An image is formed. The toner image formed on the surface of the electrophotographic photoreceptor 1 is transferred onto the transfer material 7 by a transfer bias from a transfer means (for example, a transfer roller) 6. At this time, the transfer material 7 is taken out from the transfer material supply means (not shown) in synchronism with the rotation of the electrophotographic photosensitive member 1 and is placed between the electrophotographic photosensitive member 1 and the transfer means 6 (contact portion). Be fed. Further, a bias voltage having a polarity opposite to the charge held in the toner is applied to the transfer means from a bias power source (not shown).

  The transfer material 7 onto which the toner image has been transferred is separated from the surface of the electrophotographic photosensitive member, conveyed to the fixing means 8, and subjected to fixing processing of the toner image, whereby an electrophotographic apparatus is formed as an image formed product (print, copy). Printed out.

  The transfer material 7 onto which the toner image has been transferred is separated from the surface of the electrophotographic photosensitive member 1, transported to the fixing means 8, undergoes a toner image fixing process, and is electrophotographic as an image formation (print, copy). Printed out of the device.

  The surface of the electrophotographic photosensitive member 1 after the toner image is transferred to the transfer material 7 is cleaned by the cleaning means 9 after removal of deposits such as a developer remaining after transfer (transfer residual toner). Further, the transfer residual toner can be collected by a developing means (cleanerless system).

  Further, the surface of the electrophotographic photosensitive member 1 is irradiated with pre-exposure light 10 from pre-exposure means (not shown), subjected to charge removal processing, and then repeatedly used for image formation. As shown in FIG. 3, when the charging unit 3 is a contact charging unit using a charging roller or the like, the pre-exposure unit is not necessarily required.

  In the present invention, among the components such as the electrophotographic photosensitive member 1, the charging unit 3, the developing unit 5 and the cleaning unit 9 described above, a plurality of components are housed in a container and integrally supported to form a process cartridge. May be. The process cartridge can be configured to be detachable from the main body of the electrophotographic apparatus. For example, the electrophotographic photosensitive member 1 and at least one selected from the charging unit 3, the developing unit 5, and the cleaning unit 9 are integrally supported to form a cartridge. Then, the process cartridge 11 can be detachably attached to the main body of the electrophotographic apparatus using guide means 12 such as a rail of the main body of the electrophotographic apparatus.

  The exposure light 4 may be reflected light or transmitted light from an original when the electrophotographic apparatus is a copying machine or a printer. Alternatively, it may be light emitted by reading a document with a sensor, converting it into a signal, scanning a laser beam performed in accordance with this signal, driving an LED array, or driving a liquid crystal shutter array.

<Configuration of electrophotographic photoreceptor>
The electrophotographic photoreceptor of the present invention is a cylindrical electrophotographic photoreceptor having a support and a photosensitive layer formed on the support.

  The photosensitive layer is a single layer type photosensitive layer containing a charge transporting material and a charge generating material in the same layer, but is separated into a charge generating layer containing a charge generating material and a charge transporting layer containing a charge transporting material. A (functional separation type) photosensitive layer may be used. From the viewpoint of electrophotographic characteristics, a laminated photosensitive layer is preferred. The laminated photosensitive layer is preferably a normal photosensitive layer in which a charge generation layer and a charge transport layer are laminated in this order from the support side. In addition, the charge generation layer may have a stacked structure, and the charge transport layer may have a stacked structure.

  The support is preferably one that exhibits conductivity (conductive support). Examples of the material of the support include metals (alloys) such as iron, copper, gold, silver, aluminum, zinc, titanium, lead, nickel, tin, antimony, indium, chromium, aluminum alloy, and stainless steel. In addition, for example, a metal support or a plastic support having a film formed by vacuum deposition using aluminum, an aluminum alloy, or an indium oxide-tin oxide alloy can be used.

  In addition, a support in which conductive particles such as carbon black, tin oxide particles, titanium oxide particles, and silver particles are impregnated with plastic or paper, or a support formed with a conductive binder resin can also be used.

  The surface of the support may be subjected to, for example, a cutting process, a roughening process, or an alumite process for the purpose of suppressing interference fringes due to scattering of laser light.

  For example, a conductive layer may be provided between the support and the undercoat layer described below for the purpose of suppressing interference fringes due to scattering of laser light and covering the scratches on the support. The conductive layer is formed by applying a coating solution for conductive layer obtained by dispersing carbon black, conductive pigment, and resistance adjusting pigment in a solvent together with a binder resin to form a coating film, and then drying the obtained coating film. Can be formed. Moreover, you may add to the coating liquid for conductive layers the compound which hardens and polymerizes by heating, ultraviolet irradiation, and radiation irradiation, for example.

  Examples of the binder resin used for the conductive layer include acrylic resin, allyl resin, alkyd resin, ethyl cellulose resin, ethylene-acrylic acid copolymer, epoxy resin, casein resin, silicone resin, gelatin resin, phenol resin, butyral resin, poly Examples thereof include acrylate resins, polyacetal resins, polyamideimide resins, polyamide resins, polyallyl ether resins, polyimide resins, polyurethane resins, polyester resins, polycarbonate resins, and polyethylene resins.

  Examples of the conductive pigment and the resistance adjusting pigment include particles of metal (alloy) such as aluminum, zinc, copper, chromium, nickel, silver, and stainless steel, and those obtained by vapor deposition on the surface of plastic particles. It is also possible to use metal oxide particles such as zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony or tantalum-doped tin oxide. it can.

  These may be used alone or in combination of two or more. Further, the conductive pigment and the resistance adjusting pigment can be subjected to a surface treatment. As the surface treatment agent, for example, a surfactant, a silane coupling agent, or a titanium coupling agent is used.

  Furthermore, for the purpose of light scattering, particles such as silicone resin fine particles and acrylic resin fine particles may be added. Moreover, you may contain additives, such as a leveling agent, a dispersing agent, antioxidant, a ultraviolet absorber, a plasticizer, a rectifying material.

  The thickness of the conductive layer is preferably 0.2 μm or more and 40 μm or less, more preferably 1 μm or more and 35 μm or less, and more preferably 5 μm or more and 30 μm or less.

  An undercoat layer (intermediate layer) is provided between the support or conductive layer and the photosensitive layer (charge generation layer, charge transport layer) for the purpose of improving adhesion of the photosensitive layer and improving charge injection from the support. It may be provided. The undercoat layer can be formed by forming a coating film of an undercoat layer coating solution obtained by mixing a binder resin and a solvent, and drying the coating film.

  Examples of the resin used for the undercoat layer include polyvinyl alcohol, polyethylene oxide, ethyl cellulose, methyl cellulose, casein, polyamide (nylon 6, nylon 66, nylon 610, copolymer nylon, N-alkoxymethylated nylon, etc.), polyurethane resin , Acrylic resin, allyl resin, alkyd resin, phenol resin, and epoxy resin.

  The thickness of the undercoat layer is preferably 0.05 μm or more and 40 μm or less.

  The subbing layer may contain metal oxide particles. The metal oxide particles used for the undercoat layer are preferably particles containing at least one selected from the group consisting of titanium oxide, zinc oxide, tin oxide, zirconium oxide, and aluminum oxide. Among the particles containing the above metal oxide, particles containing zinc oxide are more preferable.

  The metal oxide particles may be particles in which the surface of the metal oxide particles is treated with a surface treatment agent such as a silane coupling agent.

  Examples of the dispersion method include a method using a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, a roll mill, a vibration mill, an attritor, and a liquid collision type high-speed disperser.

  The undercoat layer may further contain, for example, organic resin particles or a leveling agent for the purpose of adjusting the surface roughness of the undercoat layer or reducing cracks in the undercoat layer. As the organic resin particles, hydrophobic organic resin particles such as silicone particles and hydrophilic organic resin particles such as cross-linked polymethacrylate resin (PMMA) particles can be used.

  Various additives can be contained in the undercoat layer. Examples of the additive include a metal, a conductive material, an electron transporting material, a metal chelate compound, and an organometallic compound such as a silane coupling agent.

  When the photosensitive layer is a laminated photosensitive layer, the charge generation layer is formed by applying a charge generation layer coating solution obtained by dispersing the charge generation material together with a binder resin and a solvent to form a coating film, and then drying it. Can be formed. The charge generation layer may be a vapor generation film of a charge generation material.

  Examples of the charge generating material used in the photosensitive layer include azo pigments, phthalocyanine pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, squarylium dyes, thiapyrylium salts, triphenylmethane dyes, and quinacridone pigments. Examples include azulenium salt pigments, cyanine dyes, anthanthrone pigments, pyranthrone pigments, xanthene dyes, quinoneimine dyes, and styryl dyes.

  These charge generation materials may be used alone or in combination of two or more. Among these, oxytitanium phthalocyanine, chlorogallium phthalocyanine, and hydroxygallium phthalocyanine are preferable from the viewpoint of sensitivity. Furthermore, among the hydroxygallium phthalocyanines, there are hydroxygallium phthalocyanine crystals having crystal forms having strong peaks at Bragg angles 2θ of 7.4 ° ± 0.3 ° and 28.2 ° ± 0.3 ° in CuKα characteristic X-ray diffraction. preferable.

  Examples of the binder resin used for the charge generation layer include polycarbonate resin, polyester resin, butyral resin, polyvinyl acetal resin, acrylic resin, vinyl acetate resin, and urea resin. Among these, a butyral resin is preferable. These may be used alone or in combination as a mixture or copolymer.

  Examples of the dispersion method include a method using a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, a roll mill, and an attritor.

  The ratio of the charge generation material and the binder resin in the charge generation layer is preferably 0.3 parts by mass or more and 10 parts by mass or less of the charge generation material with respect to 1 part by mass of the binder resin. If necessary, for example, a sensitizer, a leveling agent, a dispersant, an antioxidant, an ultraviolet absorber, a plasticizer, and a rectifying material can be added to the charge generation layer. The thickness of the charge generation layer is preferably from 0.01 μm to 5 μm, and more preferably from 0.1 μm to 2 μm.

  When the photosensitive layer is a laminated photosensitive layer, a charge transport layer is formed on the charge generation layer. The charge transport layer can be formed by applying a charge transport layer coating solution obtained by dissolving a charge transport material and a binder resin in a solvent to form a coating film and drying the coating film.

  Examples of the charge transport material include pyrene compounds, N-alkylcarbazole compounds, hydrazone compounds, N, N-dialkylaniline compounds, diphenylamine compounds, triphenylamine compounds, triphenylmethane compounds, pyrazoline compounds, styryl compounds, stilbene compounds, A butadiene compound is mentioned. These charge transport materials may be used alone or in combination of two or more. Among these charge transport materials, a triphenylamine compound is preferable from the viewpoint of charge mobility.

  Examples of the binder resin used for the charge transport layer include polyester resin, acrylic resin, polyvinyl carbazole resin, phenoxy resin, polycarbonate resin, polyvinyl butyral resin, polystyrene resin, polyvinyl acetate resin, polysulfone resin, polyarylate resin, and vinylidene chloride. , Acrylonitrile copolymer, and polyvinyl benzal resin. These may be used alone or in combination as a mixture or copolymer.

  If necessary, for example, an antioxidant, an ultraviolet absorber, a plasticizer, and a leveling agent can be added to the charge transport layer.

  The ratio of the charge transport material and the binder resin in the charge transport layer is preferably 0.3 parts by mass or more and 10 parts by mass or less of the charge transport material with respect to 1 part by mass of the binder resin. When the charge transport layer is a single layer, the thickness of the charge transport layer is preferably 5 μm or more and 40 μm or less, and more preferably 8 μm or more and 30 μm or less. When the charge transport layer has a laminated structure, the thickness of the charge transport layer on the support side is preferably 5 μm to 30 μm, and the thickness of the charge transport layer on the surface side is preferably 1 μm to 10 μm. preferable.

  Examples of the solvent used in the coating solution for the charge generation layer and the charge transport layer include alcohol solvents, sulfoxide solvents, ketone solvents, ether solvents, ester solvents, halogenated hydrocarbon solvents, and aromatic solvents. Is mentioned.

  A protective layer may be formed on the charge transport layer for the purpose of improving the abrasion resistance and cleaning properties of the electrophotographic photosensitive member. The protective layer can be formed by forming a coating film of a coating solution for the protective layer obtained by dissolving the binder resin in a solvent and drying the coating film.

  Examples of the resin used for the protective layer include polyvinyl butyral resin, polyester resin, polycarbonate resin, polyamide resin, polyimide resin, polyurethane resin, phenol resin, and polyarylate resin.

  In addition, the protective layer is formed by forming a coating film of a coating solution for the protective layer obtained by dissolving a polymerizable monomer or oligomer in a solvent, and curing (polymerizing) the coating film using a crosslinking or polymerization reaction. May be formed. Examples of the polymerizable monomer or oligomer include a compound having a chain polymerizable functional group such as an acryloyloxy group and a styryl group, and a sequentially polymerizable functional group such as a hydroxy group, an alkoxysilyl group, an isocyanate group, and an epoxy group. Compounds.

  Examples of the curing reaction include radical polymerization, ionic polymerization, thermal polymerization, photopolymerization, radiation polymerization (electron beam polymerization), plasma CVD method, and photo CVD method.

  In addition, conductive particles or a charge transport material may be added to the protective layer. As the conductive particles, a conductive pigment used in the conductive layer can be used. As the charge transport material, the above-described charge transport materials can be used.

  Furthermore, it is more preferable to use a charge transport material having a polymerizable functional group from the viewpoint of achieving both wear resistance and charge transport capability. As the polymerizable functional group, an acryloyloxy group is preferred. Further, a charge transport material having two or more polymerizable functional groups in the same molecule is preferable.

  Further, the surface layer (charge transport layer or protective layer) of the electrophotographic photoreceptor may contain organic resin particles or inorganic particles. Examples of the organic resin particles include fluorine atom-containing resin particles and acrylic resin particles. Inorganic particles include alumina, silica, and titania. Furthermore, you may add electroconductive particle, antioxidant, a ultraviolet absorber, a plasticizer, a leveling agent, etc.

  The thickness of the protective layer is preferably from 0.1 to 30 μm, and more preferably from 1 to 10 μm.

  As a method for applying the coating solution for each layer, for example, a dip coating method (dip coating method), a spray coating method, a spinner coating method, a roller coating method, a Meyer bar coating method, and a blade coating method can be used.

  Hereinafter, the present invention will be described in more detail with reference to specific examples. In the examples, “part” means “part by mass”.

(Example of photoconductor-1 production)
An aluminum cylinder having a diameter of 30 mm and a length of 357.5 mm was used as a cylindrical support (conductive support).

Next, 100 parts of zinc oxide particles (specific surface area: 19 m ² / g, powder resistance: 4.7 × 10 ⁶ Ω · cm) are stirred and mixed with 500 parts of toluene, and a silane coupling agent (compound name: 0.8 part of N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, trade name: KBM602, manufactured by Shin-Etsu Chemical Co., Ltd.) was added and stirred for 6 hours. Thereafter, toluene was distilled off under reduced pressure, followed by heating and drying at 130 ° C. for 6 hours to obtain surface-treated zinc oxide particles.

  Next, 15 parts of butyral resin (trade name: BM-1, manufactured by Sekisui Chemical Co., Ltd.) and 15 parts of blocked isocyanate (trade name: Sumidur 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.) were added to 73.5 parts of methyl ethyl ketone. 1-butanol was dissolved in a mixed solution of 73.5 parts. 80.8 parts of surface-treated zinc oxide particles and 0.8 part of 2,3,4-trihydroxybenzophenone (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to this solution, and this was added to glass beads having a diameter of 0.8 mm. Was dispersed in an atmosphere of 23 ± 3 ° C. for 3 hours. After dispersion, 0.01 parts of silicone oil (trade name: SH28PA, manufactured by Toray Dow Corning Silicone), cross-linked polymethyl methacrylate (PMMA) particles (trade name: TECHPOLYMER SSX-102, manufactured by Sekisui Plastics Co., Ltd.) 5.6 parts of an average primary particle size of 2.5 μm) was added and stirred to prepare an undercoat layer coating solution.

  This undercoat layer coating solution was dip-coated on a cylindrical support to form a coating film, and the coating film was dried at 160 ° C. for 40 minutes to form an undercoat layer having a thickness of 18 μm.

  Next, 20 parts of a crystalline form of a hydroxygallium phthalocyanine crystal (charge generation material) having strong peaks at 7.4 ° and 28.2 ° with a Bragg angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction, 0.2 part of the compound represented by 1),

10 parts of polyvinyl butyral (trade name: ESREC BX-1, manufactured by Sekisui Chemical Co., Ltd.) and 600 parts of cyclohexanone were placed in a sand mill using glass beads having a diameter of 1 mm and dispersed for 4 hours. Thereafter, 700 parts of ethyl acetate was added to prepare a charge generation layer coating solution. This coating solution for charge generation layer was dip coated on the undercoat layer to form a coating film, and the coating film was dried at 80 ° C. for 15 minutes to form a charge generation layer having a thickness of 0.17 μm.

  Next, 30 parts of a compound represented by the following formula (B) (charge transporting substance), 60 parts of a compound represented by the following formula (C) (charge transporting substance), 10 parts of a compound represented by the following formula (D), polycarbonate 100 parts of resin (trade name: Iupilon Z400, manufactured by Mitsubishi Engineering Plastics Co., Ltd., bisphenol Z-type polycarbonate), polycarbonate having two structural units represented by the following formula (E) (viscosity average molecular weight Mv: 20000) 0 A coating solution for a charge transport layer was prepared by dissolving 0.02 part in a mixed solvent of 600 parts of mixed xylene and 200 parts of dimethoxymethane. This charge transport layer coating solution was applied onto the charge generation layer by dip coating to form a coating film, and the coating film was dried at 100 ° C. for 30 minutes to form a charge transport layer having a thickness of 18 μm.

(In the formula (E), 0.95 and 0.05 indicate the copolymerization ratio of the two structural units.)

  Next, a mixed solvent of 20 parts of 1,1,2,2,3,3,4-heptafluorocyclopentane (trade name: Zeolora H, manufactured by Nippon Zeon Co., Ltd.) / 20 parts of 1-propanol was added to polyflon. The mixture was filtered with a filter (trade name: PF-040, manufactured by Advantech Toyo Co., Ltd.). Thereafter, 90 parts of a hole transporting compound represented by the following formula (F),

70 parts of 1,1,2,2,3,3,4-heptafluorocyclopentane and 70 parts of 1-propanol were added to the mixed solvent. By filtering this with a polyflon filter (trade name: PF-020, manufactured by Advantech Toyo Co., Ltd.), a coating solution for a protective layer (second charge transport layer) was prepared. This protective coating solution was dip-coated on the charge transport layer, and the resulting coating film was dried at 50 ° C. for 6 minutes in the air. Thereafter, the coating film was irradiated with an electron beam for 1.6 seconds under the conditions of an acceleration voltage of 70 kV and an absorbed dose of 8000 Gy while rotating the support (irradiated body) at 200 rpm in a nitrogen atmosphere. Subsequently, the temperature was raised from 25 ° C. to 125 ° C. over 30 seconds in a nitrogen atmosphere, and the coating film was heated. The oxygen concentration in the atmosphere during electron beam irradiation and subsequent heating was 15 ppm. Next, a protective layer having a thickness of 5 μm was formed by performing heat treatment at 100 ° C. for 30 minutes in the air.

Forming of concave / convex shape by die member press-contact shape transfer The concave / convex shape was transferred by a press-contact shape transfer processing apparatus having a configuration shown in FIG. As the surface shape of the mold member, a shape in which random convex portions (by an error diffusion method (Floyd & Steinberg method)) as shown in FIG. In FIG. 4 (A), the convex portion used was a dome shape having a diameter of 50 μm and a height H of 3 μm when viewed from above. The area occupied by the convex shape on the entire surface of the mold member was 10%.

  The electrophotographic photosensitive member before the formation of the concavo-convex shape is inserted into the insertion member 2-2 shown in FIG. 2 made of cemented carbide D40, and is inserted into the supporting member 2-4 of the electrophotographic photosensitive member 2-1. Installed.

  During the surface processing, the temperature is controlled so that the surface temperature of the mold member is 150 ° C. and the surface temperature of the electrophotographic photosensitive member is 55 ° C., and the electrophotographic photosensitive member and the pressure member are moved while being pressed at a pressure of 30 MPa. It was. Then, by rotating in the circumferential direction of the electrophotographic photosensitive member, the concavo-convex shape is transferred to the electrophotographic photosensitive member so that Wb = 1 mm, and the obtained electrophotographic photosensitive member is “photosensitive member-1”. Is shown in Table 1.

(Production Example of Photoreceptor-2 to Photoreceptor-16)
An electrophotographic photosensitive member was manufactured in the same manner as in the manufacturing example of the photosensitive member-1, except that Wb was changed to the value shown in Table 1 in the manufacturing example of the photosensitive member-1. The obtained electrophotographic photosensitive member having a concavo-convex shape on its surface was designated as “photosensitive member-2” to “photosensitive member-16”, and the results are shown in Table 1.

(Production example of photoconductor-17)
After transferring the concavo-convex shape in the same manner as in the photoconductor-1 production example, the concavo-convex shape was transferred again in the same manner to produce an electrophotographic photosensitive member. The obtained electrophotographic photosensitive member having a concavo-convex shape on the surface was designated as “photosensitive member-17”, and the results are shown in Table 1.

(Production example of photoconductor-18)
In the production example of the photoconductor-1, the electrophotographic photoconductor and the pressure member were pressed at a pressure of 30 MPa while being moved by 242 mm so that Wb = 94.2 mm was obtained. Thus, an electrophotographic photosensitive member was produced. The obtained electrophotographic photosensitive member having a concavo-convex shape on the surface was designated as “photosensitive member-18”, and the results are shown in Table 1.

(Production example of photoconductor-101 to photoconductor-111)
In the production example of the photoreceptor 1, as shown in Table 4 (B), the shape when viewed from above is a circular shape with a diameter of 5 μm, and has a cylindrical convex portion with a height H of 3 μm. A mold member in which the area occupied by the part shape on the entire surface of the mold member was 70% was used. An electrophotographic photosensitive member was manufactured in the same manner as in the manufacturing example of the photosensitive member-1, except that the mold member was used and Wb was changed to the value shown in Table 2. The obtained electrophotographic photosensitive member having a concavo-convex shape on its surface was designated as “photosensitive member-101” to “photosensitive member-111”, and the results are shown in Table 2.

(Production example of photoconductor 112)
After transferring the concavo-convex shape in the same manner as in the photoconductor-101 production example, the concavo-convex shape was transferred again in the same manner to produce an electrophotographic photosensitive member. The obtained electrophotographic photosensitive member having a concavo-convex shape on the surface was designated as “photosensitive member-112”, and Table 2 shows the results.

(Example of manufacturing photoconductor 113)
In the photoconductor-101 production example, the electrophotographic photoconductor and the pressing member were moved by 242 mm at a pressure of 50 MPa and moved to 242 mm so that Wb = 94.2 mm. Thus, an electrophotographic photosensitive member was produced. The obtained electrophotographic photosensitive member having recesses on the surface was designated as “photosensitive member-113”, and the results are shown in Table 2.

(Example of photoconductor-201 production)
In the production example of photoconductor-1, the temperature of the surface of the mold member is controlled to 23 ° C. and the surface temperature of the electrophotographic photoconductor is 23 ° C., and the electrophotographic photoconductor and the pressure member at a pressure of 50 MPa. The concavo-convex shape was transferred while pressing. Otherwise, an electrophotographic photoreceptor was produced in the same manner as in the photoreceptor-1 production example. The obtained electrophotographic photosensitive member having a concavo-convex shape on the surface was designated as “photosensitive member-201”, and the results are shown in Table 3.

(Production Example of Photoconductor-202 to Photoconductor-211)
In the production example of the photoconductor-201, an electrophotographic photoconductor was produced in the same manner as in the production example of the photoconductor-201 except that Wb was changed to the value shown in Table 3. The obtained electrophotographic photosensitive member having a concavo-convex shape on its surface was designated as “photosensitive member-202” to “photosensitive member-211”, and the results are shown in Table 3.

(Production example of photoconductor-212)
After transferring the concavo-convex shape in the same manner as in the production example of the photoconductor 201, the concavo-convex shape was transferred again in the same manner to manufacture an electrophotographic photosensitive member. The obtained electrophotographic photosensitive member having a concavo-convex shape on the surface was designated “photosensitive member-212”, and the results are shown in Table 3.

(Production example of photoconductor-213)
In the production example of the photoconductor-201, everything is the same as the production example of the photoconductor-201 except that the electrophotographic photoconductor and the pressing member are moved by 242 mm while pressing at 50 MPa so that Wb = 94.2 mm. Thus, an electrophotographic photosensitive member was produced. The obtained electrophotographic photosensitive member having a concavo-convex shape on the surface was designated as “photosensitive member-213”, and the results are shown in Table 3.

(Production example of photoconductors 1001 to 1012)
In the production example of Photoreceptor-1, the length Wm of the electrophotographic photoconductor in the rotation direction of the area where the uneven shape on the surface of the electrophotographic photoconductor was not transferred was changed to the value shown in Table 4. Otherwise, the electrophotographic photosensitive member was manufactured in the same manner as in the manufacturing example of the photosensitive member-1. The obtained electrophotographic photosensitive member having an uneven shape on the surface was designated as “photosensitive member-1001” to “photosensitive member-1012”, and the results are shown in Table 4. Region B was not observed on the photoreceptors 1001 to 1012.

(Example of production of photoconductors 1013 to 1024)
An electrophotographic photosensitive member was manufactured in the same manner as in the manufacturing example of the photosensitive member 201 except that Wm was changed to the value shown in Table 4 in the manufacturing example of the photosensitive member 201. The obtained electrophotographic photosensitive member having a concavo-convex shape on its surface was designated as “photosensitive member-1013” to “photosensitive member-1024”, and the results are shown in Table 4. Region B was not observed on the photoreceptors 1013 to 1024.

-Evaluation of electrophotographic photosensitive member having uneven shape (Example A-1)
Photoreceptor-1 is mounted on a cyan station of a modified machine of an electrophotographic apparatus (copier) (trade name: iR-ADV C5255) manufactured by Canon Inc., which is an evaluation apparatus, and tested and evaluated as follows. It was.

  First, in a 23 ° C./50% RH environment of an electrophotographic photosensitive member, a charging device and an image exposure device so that the dark portion potential (Vd) of the electrophotographic photosensitive member is −700 V and the bright portion potential (Vl) is −200 V. The initial potential of the electrophotographic photosensitive member was adjusted.

Next, the setting of the cleaning blade was adjusted in region A using an electrophotographic photosensitive member having an uneven shape similar to that of “photosensitive member-1” prepared in advance and having Wb = 0. Thereafter, a cleaning blade is installed on a semicylindrical glass having the same outer diameter as that of the electrophotographic photosensitive member, and the above W is used from the back surface of the semicylindrical glass using a digital microscope VHX-500 manufactured by Keyence Corporation. Was measured. W was 30 μm. Next, the semi-cylindrical semi-cylindrical glass was changed to “photosensitive body-1”, and the following abnormal noise and image evaluation were performed.
・ Sound and image evaluation method A test chart in which alphabets (A to Z) of 2 point size and 3 point size and complex Chinese characters (Den, Surprise, etc.) are arranged at an A4 horizontal output resolution of 600 dpi. Created.

  For abnormal noise, turn on the power with the pre-rotation of the electrophotographic photosensitive member in the electrophotographic apparatus turned off, measure the time from when the test chart printout starts until no abnormal noise is heard, The rank was determined.

  Regarding the cleaning property, after 10,000 images were continuously printed out, the electrophotographic apparatus was left in an environment at a temperature of 5 ° C. for 24 hours. Next, 10 solid white images were printed out continuously, 10 solid black images were output, and immediately after that, one halftone image was output, and evaluation was performed using this halftone image. Specifically, the occurrence of toner slipping considered to be a cleaning defect in the output image was visually counted to perform rank evaluation.

Rank evaluation of abnormal noise A: No abnormal noise can be heard within 2 seconds from the start of rotation of the photosensitive member. Or no abnormal noise is generated from the start of rotation. B: No abnormal noise is heard within 10 seconds from the start of rotation of the photosensitive member.
C: Abnormal noise is not heard within 30 seconds from the start of photoconductor rotation D: Abnormal noise is heard even after 30 seconds from the start of photoconductor rotation.

Rank evaluation of cleaning performance A: No image streak and good image quality B: No image streak and good image quality, but non-image region has a slight loss of toner but is within an acceptable range A: There is no streak in the image area and the image quality is good, but a very slight streak is generated in the non-image area but it is an allowable range. D: A slight streak is generated in the image area, but it is an allowable range. .

  The results are shown in Table 5.

(Example A-2 to Example A-13)
The electrophotographic photosensitive member was evaluated in the same manner as in Example A-1, except that the electrophotographic photosensitive member shown in Table 5 was used. The results are shown in Table 5.

(Example B-1 to Example B-13)
The electrophotographic photosensitive member shown in Table 6 was used, and the setting of the cleaning blade was changed so that the W was 50 μm. Otherwise, the electrophotographic photoreceptor was evaluated in the same manner as in Example A-1. The results are shown in Table 6.

(Example C-1 to Example C-13)
The electrophotographic photosensitive member shown in Table 7 was used, and the setting of the cleaning blade was changed so that the W was 20 μm. Otherwise, the electrophotographic photoreceptor was evaluated in the same manner as in Example A-1. The results are shown in Table 7.

(Example D-1 to Example D-13)
The electrophotographic photosensitive member shown in Table 8 is used, and the cleaning blade is set in the region A using an electrophotographic photosensitive member having a concavo-convex shape similar to that of “photosensitive member-101” prepared in advance and having Wb = 0. Were adjusted to the values shown in Table 8. Otherwise, the electrophotographic photoreceptor was evaluated in the same manner as in Example A-1. The results are shown in Table 8.

(Example E-1 to Example E-13)
The electrophotographic photosensitive member shown in Table 9 is used, and the cleaning blade is set in the region A using an electrophotographic photosensitive member having a concavo-convex shape similar to that of “photosensitive member-201” prepared in advance and Wb = 0. Were adjusted to the values shown in Table 9. Otherwise, the electrophotographic photoreceptor was evaluated in the same manner as in Example A-1. The results are shown in Table 9.

Claims (6)

A method of forming a concavo-convex shape on the surface of a cylindrical electrophotographic photosensitive member,
The electrophotographic photosensitive member is brought into pressure contact with a plate-shaped mold member having a surface shape corresponding to the uneven shape, and the surface shape of the surface of the mold member is changed to the electrophotographic photosensitive member while rotating the electrophotographic photosensitive member. Having a process of transferring to the surface of the body,
The surface of the electrophotographic photoreceptor is
Region A in which the mold member is brought into pressure contact n times to transfer the surface shape onto the surface of the electrophotographic photosensitive member n times, and the mold member is brought into pressure contact at least n + 1 times adjacent to the region A A surface processing method for a cylindrical electrophotographic photosensitive member, comprising a region B in which the surface shape is transferred to the surface of the electrophotographic photosensitive member n + 1 times or more.   The electrophotographic photosensitive member according to claim 1, wherein n is 1. The length of the contact area between the cleaning blade as the cleaning member and the electrophotographic photosensitive member in the rotation direction of the electrophotographic photosensitive member is W,
When the length of the region B in the rotation direction of the electrophotographic photosensitive member is Wb,
W and Wb are represented by the following formula (1)
Wb> W (1)
The surface processing method for a cylindrical electrophotographic photosensitive member according to claim 1, wherein: Wb is the following formula (2)
40 mm ≧ Wb (2)
The surface processing method for a cylindrical electrophotographic photosensitive member according to claim 3, wherein: Wb is the following formula (3)
20 mm ≧ Wb ≧ 0.5 mm (3)
5. The surface processing method for a cylindrical electrophotographic photosensitive member according to claim 3, wherein: An electrophotographic photosensitive member is produced, and the method includes a step of forming a concavo-convex shape on the surface of the cylindrical electrophotographic photosensitive member using the surface processing method according to any one of claims 1 to 5. A method for producing a cylindrical electrophotographic photosensitive member having a concavo-convex shape on a surface thereof.

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