JP2010145793A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a sliding sound between a cleaning blade and an electrophotographic photoreceptor. <P>SOLUTION: An image forming apparatus is mounted with at least the electrophotographic photoreceptor having a photosensitive layer and surface layer on a conductive support body, and the cleaning blade for cleaning a foreign substance including a remaining powder. The electrophotographic photoreceptor has a projection on a surface of a surface layer, and the surface layer and the projection contain a crosslinking body of the same charge transportable compound. When the roughness of the surface layer is expressed by RzJIS, the number of projections having a height of 1/2×RzJIS or higher is between 20 and 80 per measuring length of 12 mm. The cleaning blade includes a hard coat resin layer in an abutting part on the electrophotographic photoreceptor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus capable of maintaining high-quality printing over a long period of time. Furthermore, the present invention relates to an image forming apparatus that realizes silent printing.

  In order to extend the life of the electrophotographic apparatus not only to reduce the printing cost but also to reduce the environmental load, this technical development has been vigorously advanced. Among electrophotographic apparatuses, the electrophotographic photosensitive member has a strong personality as a supply product, and the above-described merit is expanded as the durability increases.

  Various attempts have been made to increase the durability of electrophotographic photosensitive members. At present, the formation of a crosslinked resin film on the surface of an electrophotographic photoreceptor (for example, Patent Document 1) and the formation of a sol-gel cured film on the surface of an electrophotographic photoreceptor (for example, Patent Document 2) are particularly promising. . The former has the merit that even when a charge transporting component is blended, cracks and cracks hardly occur and the production yield can be reduced. Of these, radically polymerizable acrylic resins are advantageous because they are easy to obtain an electrophotographic photoreceptor having toughness and good sensitivity characteristics. In these two types of measures taking a cross-linked structure, a coating film is formed by a plurality of chemical bonds. Therefore, even if the coating film is stressed and a part of the chemical bond is broken, it does not immediately progress to wear.

  On the other hand, with the increase in output of color images, high image quality is required more than before, but in particular, cleaning performance of residual toner remaining on the electrophotographic photosensitive member for each image formation is required more than before. Yes. This is because the wear durability of the electrophotographic photosensitive member is realized as described above, but the durability of the cleaning performance is still unsatisfactory compared to the wear resistance. In long-term repeated image formation, small scratches and cracks may occur on the surface of the electrophotographic photosensitive member, and the blade slides on the surface of the electrophotographic photosensitive member with the tip of a hard blade for cleaning. In some cases, fine toner may slip through. In particular, when the latter occurs, black streaks appear in the image and the image quality deteriorates at a stroke. Image degradation due to toner slipping has become an urgent issue for highly durable electrophotographic photoreceptors.

  On the other hand, the inventors have found that the cleaning performance of the polymerized toner is drastically improved by providing a hard coat resin layer at the edge portion of the cleaning blade that contacts the electrophotographic photosensitive member. A cleaning blade having this configuration is disclosed in Patent Document 3, for example. However, when an electrophotographic photosensitive member provided with a surface layer of a crosslinkable resin and a cleaning blade provided with a hard coat resin layer are used in combination, a rubbing sound of about 5 kHz (hereinafter referred to as blade squeal) is generated and cannot be used. New challenges remained.

Regardless of the use of the special cleaning blade as described above, the generation of unpleasant rubbing noise has sometimes become a problem in image forming apparatuses, and various countermeasures have been proposed.
For example, in Patent Document 4, the surface of the object to be processed is roughened by colliding the surface of the electrophotographic photosensitive member with a powder having an average particle size of 10 to 60 μm in the volume-based particle size distribution. It has been proposed to obtain an electrophotographic photosensitive member in which the surface of the surface layer constituting the surface of the electrophotographic photosensitive member is roughened. From the contents of this related group application, damage that causes the powder to collide with the electrophotographic photosensitive member cannot be ignored. In addition, this method does not necessarily eliminate the squeal when using a cleaning blade having a cross-linked resin film on the edge.

  In Patent Document 5, the electrophotographic photosensitive member has at least a photosensitive layer and a surface protective layer in which an inorganic filler is dispersed in a resin, and the ten-point average roughness Rz of the surface protective layer is 0.3 to 2.0 μm. A method is disclosed. Various electrophotographic photoreceptors in which an inorganic filler is contained in the photosensitive layer have been conventionally proposed. In addition, the noise has not been eliminated for these electrophotographic photosensitive members, and various measures have been proposed. That is, adding an inorganic filler to the photosensitive layer does not necessarily eliminate squeal. In addition, various undulations exist even in samples showing the same Rz, and the surface roughness of the electrophotographic photosensitive member cannot be specified sufficiently.

Patent Document 6 proposes a measure for preventing noise by inserting a balancer into the electrophotographic photosensitive drum. If a balancer is included, it is not a good idea that a shaft that is advantageous for improving the accuracy of driving an electrophotographic photosensitive member cannot be used, that it is difficult to apply to a large drum diameter, and that the cost is increased.
Patent Document 7 discloses a method of blending fluororesin fine particles in the surface layer of the electrophotographic photosensitive member. The inclusion of the fluororesin fine particles brings about a decrease in the hardness of the surface layer, which causes a new problem and is not a good idea.

As described above, the electrophotographic photosensitive member is gaining high durability by applying the surface protective layer technology. When the durability of the electrophotographic photosensitive member was realized, the lifetime of the image forming engine was determined by factors other than the lifetime of the electrophotographic photosensitive member. The main thing is wear of the cleaning blade.
As a means for suppressing the wear of the cleaning blade, a method of coating the edge portion with a hard coat material is advantageous. However, this combination was hampered by blade noise. Various countermeasures related to conventional blade squeal have been proposed, but for special photoconductors with a cured film on the surface, the effect is low, the cost increases, and the wear resistance of the corners is impaired. Etc., all the measures that deviated from the intended purpose. A new measure has been required for the combined use of a photosensitive member having a hardened film on the surface and excellent abrasion resistance and a cleaning blade.
JP 2000-66424 A JP 2000-171990 A Japanese Patent No. 3602898 JP 2006-267855 A JP 2004-233881 A JP 2003-215829 A Japanese Patent Laid-Open No. 2003-5606

  The present invention solves the above-described problems of the prior art, and relates to an image forming apparatus using both a cleaning blade having a hard coat resin layer at an edge portion and an electrophotographic photosensitive member having a cross-linked resin surface layer laminated. The object is to prevent rubbing noise with a photographic photoreceptor.

The inventors presume that blade squeal is a phenomenon affected by the following stick-slip motion, and thought that this problem can be solved by suppressing this phenomenon.
A blade cleaning method is often used for a cleaning member used in an image forming apparatus. The cleaning blade is a rubber plate (blade) formed into a plate shape fixed to a support such as an aluminum plate or an iron plate. A constant load (pressing) is applied, and the edge of the blade is applied to the electrophotographic photosensitive member. It is installed so that it abuts. As a means for contacting the electrophotographic photosensitive member, a method in which the blade edge makes contact with the electrophotographic photosensitive member in the counter direction (the direction in which the blade edge bites when the electrophotographic photosensitive member rotates = reverse direction) is a cleaning property. In many cases, it is excellent in general. FIG. 21 shows a case where a cleaning blade of this counter method is used. As the doctor blade B, an elastic material that can easily obtain bending rigidity is preferably used. For example, when a drum-shaped electrophotographic photosensitive member A is used, the electrophotographic photosensitive member A is installed at a position of an angle θ so as to be a counter with respect to the driving (rotating) direction R of the electrophotographic photosensitive member A, and cleaned on the electrophotographic photosensitive member. Bring the blade into contact. Further, the toner is cleaned by scraping off the toner remaining on the surface of the latent image carrier by pressing the tip against the bite (the biting amount indicated by d in the figure). However, when the friction coefficient of the surface of the latent image carrier increases under this contact condition, the leading edge surface B1 of the doctor blade B is dragged along the rotation direction of the latent image carrier A as shown in FIG. Thus, the pulled position becomes a wedge shape that forms a wedge-shaped space C with the surface of the latent image carrier.

  As shown in FIG. 23, when the blade tip B1 is dragged to the latent image carrier A to form a wedge shape, and toner (referred to as T for convenience) accumulates in the wedge-shaped space C, the blade tip B1 becomes the latent image carrier. An operation of returning to the original shape (the shape indicated by the solid line in FIG. 24) occurs due to the elastic restoring force accompanying the stress generated when the wire is dragged by A (the operation in the direction indicated by the symbol SS in FIG. 24). This phenomenon is stick-slip motion.

When the electrophotographic photosensitive member is driven in the image forming apparatus, the cleaning blade in contact with the electrophotographic photosensitive member is pulled to the driving direction of the electrophotographic photosensitive member to some extent, and this causes a stick-slip motion. This stick-slip motion moves in the direction of the restoring state at once when the restoring force due to the elasticity of the cleaning blade becomes larger than the maximum static frictional force on the electrophotographic photosensitive member, and then the cleaning blade moves when the restoring force is weakened. Is interpreted as a movement that is dragged again in the driving direction of the photosensitive member.
It was considered that if a specific convex shape was applied to the surface of the electrophotographic photosensitive member, the vibration of the cleaning blade was added according to the period of the convex shape of the photosensitive member surface, and the blade squeal was alleviated. When the surface of the photoreceptor is roughened by the measures described later, the effect of eliminating the blade squealing has been found, and the present invention has been completed.

That is, the present invention relates to an image forming apparatus as described below.
(1) In an image forming apparatus equipped with at least an electrophotographic photosensitive member having a photosensitive layer and a surface layer on a conductive support, and a cleaning blade for cleaning foreign matter including residual powder, The electrophotographic photosensitive member has a convex portion formed on the surface of the surface layer, the surface layer and the convex portion contain a cross-linked body of the same charge transporting compound, and the surface roughness of the surface layer is RzJIS. When expressed, the number of convex portions having a height of ½ × RzJIS or more is 20 or more and 80 or less per 12 mm measurement length, and the cleaning blade is An image forming apparatus comprising a hard coat resin layer at a contact portion.
(However, RzJIS means the ten-point average roughness of the 2001 JIS standard (JIS B0601: '01). The height of the convex portion is the distance from the waviness curve of the surface layer to the top of the convex portion, and (An average value obtained by measuring at least four locations at arbitrary positions in the formation region.)
(2) The image forming apparatus as described in (1), wherein the RzJIS average value of the electrophotographic photosensitive member is from 0.05 μm to 6 μm.
(3) The image forming apparatus according to (1) or (2), wherein the curable resin of the electrophotographic photosensitive member contains a cross-linked product of a charge transporting compound having a triarylamine structure.
(4) The image forming apparatus as described in (3), wherein the curable resin of the electrophotographic photosensitive member contains at least a cross-linked product of a charge transport material of the following general formula 1.
(Wherein, d, e and f are each an integer of 0 or 1, R ₁₃ represents a hydrogen atom or a methyl group, R ₁₄ and R ₁₅ represent a substituent other than a hydrogen atom and an alkyl group having 1 to 6 carbon atoms. And may be different from each other, g and h each represent an integer of 0 to 3. Z is a single bond, a methylene group, an ethylene group,
Or
Represents. )
(5) The image forming apparatus according to any one of (1) to (4), wherein the method for forming the convex portions of the electrophotographic photosensitive member is a spray coating method.
(6) The image forming apparatus according to any one of (1) to (5), wherein development is performed using at least a polymerized toner.
(7) The image forming apparatus according to (6), which has at least two or more development stations and is of a tandem system.
(8) Any one of (6) to (7), wherein the image forming apparatus includes a process cartridge that can be attached to and detached from an image forming apparatus main body including at least an electrophotographic photosensitive member, a developing unit, and a cleaning unit. The image forming apparatus described.

  According to the present invention, since the cleaning blade made of an elastic body is brought into contact with the tops of a large number of convex portions, the blade slides better because it is held at a large number of contact points. Since the groove portions are connected, foreign matter is often easily discharged. Further, by repeating the image forming process, even if the convex portion is destroyed, the destruction is often limited to the convex portion, which is convenient. The convex portion of the present invention can solve the problem more excellently than the conventional configuration in which many concave portions are provided.

The present invention is implemented by the configuration of an electrophotographic photosensitive member, a cleaning blade, and an image forming apparatus using the same, which will be described below for each item.
The present inventors have a large number of protrusions formed on the surface of the surface layer of the electrophotographic photosensitive member, and the surface layer and the protrusions contain the same charge transporting compound cross-linked body, and The inventors have found that the above problems can be solved by defining the height and the number of the convex portions at a specific measurement length, and have reached the present invention. Conventionally, methods for determining and grasping the phenomenon related to the blade cleaning property of the photoreceptor by using property parameters such as Rz and Ra representing the surface roughness of the photoreceptor have been used, but the surface cannot be grasped by these property parameters. The property was taken up as a problem and the present invention was achieved.
Hereinafter, a surface layer containing a cross-linked product of a charge transporting compound may be referred to as a “cross-linked surface layer”.

  An example of the concept of the independent convex portion of the present invention is shown in FIG. 1 (perspective view). This convex portion protrudes outward from the surface of the photoreceptor. A convex part can be defined as a convex part having a height of 1/2 or more of Rz in a specified measurement length. This specific convex part is important for the cleaning property. Next, it is preferable that the convex portions are independent. Further, it is preferably polished or smooth. The skirt may be a groove that surrounds the protrusion and separates the other protrusion.

FIG. 2 of the present invention shows randomly arranged convex portions. The measuring direction can be arbitrarily determined as long as it is an image forming surface of the photoreceptor. The measurement direction in the case of the cylindrical photosensitive member may be any of the circumferential direction, the axial direction, and the direction between them, but is set to the axial direction for convenience from the form of the measuring table of the roughness measuring machine. Spray coating was performed under different conditions on a cylindrical laminated photoreceptor having a surface comprising a charge transport layer, and six types of surfaces with different convex portions were obtained. The conditions were as follows: spraying speed 10 (mm / s), photoreceptor speed 200 (rpm), spray gun opening 8 (scale number), and atomization pressure 2 (kgf / mm ² ). When four points were measured as measurement data at arbitrary positions in the axial direction of the surface of the photoreceptor, all of them were similar roughness curves. Moreover, the value of Rz had a small specific fluctuation. These results are shown in the examples. The measurement results are shown in Table 1 below.

The number of convex portions having a height of ½ × Rz or more is shown in Table 2 below.

  Regarding the number of protrusions, a measurement result that picks up only the valley or a measurement result that has a specific variation such as picking up only the top of the protrusion could not be obtained. Therefore, the average value of the number of convex portions obtained from the above roughness curve is considered to represent the number of convex portions randomly arranged on the actual surface.

  The convex part in this invention can grasp | ascertain that the height of a convex part is a convex part larger than 1/2 of Rz, when a roughness curve is obtained with a surface roughness meter. As will be described in detail, any technique including a known technique may be used as a method for realizing a specific independent protrusion on the photoreceptor of the present invention. The method for forming the convex portion is a method of forming the convex portion forming coating liquid by atomizing and transferring it from the outside, or forming the surface with mechanical or thermal energy applied to the surface once formed. There is a way. Examples of the former include a spray coating method, an inkjet method, and a printing method. In the latter, there are a mold processing method using a female mold, and a groove portion around a convex portion by laser ablation using a mask. As a result, it is sufficient that a convex portion is formed. Both can be used in the present invention. The former is preferably less distorted. Since the latter is accompanied by destruction of the surface layer, it is positioned as a method next to the former. Further, when processing strain is involved, thermal annealing may be added later.

  In particular, a plurality of independent convex portions by the spray coating method were confirmed by a laser microscope image, and the shape of the convex portion like a “bell” was confirmed at an aspect ratio of 50: 1. It was the shape of rotating a parabola. The shape is expected to be unique to the method of forming the protrusions. FIG. 3 shows a conceptual diagram when the vertical and horizontal magnifications are close to each other. Expected to be close to the cross-sectional shape of the bell extended in the horizontal direction.

  The configuration in which the above-described independent convex portions of the present invention are provided on the surface is not provided with many fine concave portions on the surface of the photosensitive member as disclosed in Japanese Patent Application Laid-Open No. 2007-233359. It is not a well-shaped uneven portion as described in Japanese Patent No. 233359.

  According to the present invention, it is possible to provide an image forming apparatus in which an electrophotographic photosensitive member having a highly durable and suitable rough surface and a cleaning blade having excellent wear resistance can be used in combination. Since the electrophotographic photosensitive member mounted in the present invention has a controlled convex portion formed on the surface, it is possible to prevent the rubbing noise between the electrophotographic photosensitive member and the cleaning blade.

  Although FIG. 4 (FIGS. 4-1 to 4-5) shows a conceptual example of the shape and arrangement of the convex portions of the present invention, it is not limited to these. FIG. 4 shows the shape of a cross section (plan view) at a height of one half of Rz of the convex portion. The shape of the cross section may be any shape as long as it has the above configuration. The arrangement of the convex portions may be random or regular. The shaded portion is a convex portion, and the convex portion indicates that the region is outside the surface of the photoreceptor from a region other than the shaded portion.

  In the present invention, the density (also referred to as “surface density” of the convex portions) can be defined by measuring the number of convex portions within a specified area at an arbitrary position on the surface of the photoreceptor. An area for measurement in an appropriate range is designated by the shape and size of the convex portion. Usually, the area is 100 μm square to 15 mm square. For example, in the case of the spray coating method, about 1 mm to 15 mm square is selected. However, the method for defining the surface density of the protrusions is limited to a measuring machine, and dedicated measurement software is often required, so that it may not be possible to measure easily. The present invention adopts a method of performing simple measurement using an easy-to-use surface roughness meter at least four times, obtaining an average value of the number of convex portions having a height of 1/2 × RzJIS or more, and defining the average value. To ensure measurement reliability. Therefore, it was specified by specifying a measurement length of 12 mm at an arbitrary position on the surface and measuring the number of convex portions on the surface.

  The case where the number of convex parts is measured will be specifically described. First, RzJIS conforming to JIS B0601: '01 is obtained. In the present invention, an example using a shape measuring instrument (Surfcom 1400D (measuring element DT43801) manufactured by Tokyo Seimitsu Co., Ltd.) capable of measuring surface roughness is shown, but the present invention is not limited to this. The density of the projections of the present invention is measured by counting the number of projections having a height of ½ × RzJIS or higher.

The lateral length is usually about 100 μm to 15 mm, although it depends on the surface forming method, the particle size of the toner used or the properties of the blade. About the convex part of the surface layer by spray coating, 1 mm to 15 mm can be selected. When convex portions are formed on the surface of the photoreceptor by spray coating, it is preferable that there are 20 to 80 convex portions per 12 mm measurement length.
The height of the convex portion on the surface of the photoreceptor is configured in an appropriate range. The height of the convex portion is usually 0.03 μm to 10 μm, preferably 0.05 μm to 6 μm. If it is smaller than this, the effect of providing the convex portion is poor, and it approaches the surface of the photoreceptor without the convex portion. If it is larger than this, the toner may slip through. The height can be determined according to the volume average particle diameter of the toner. It is preferable to make the volume average particle diameter of the toner or less.

  In the present invention, the surface layer of the photoreceptor contains a cross-linked product of a charge transporting compound, and the convex portions formed on this surface layer contain the same cross-linked product of the charge transporting compound as the surface layer. It is. The cross-linked structure of the cross-linked body increases the curing density, and has high hardness and high elasticity, which is effective for improving the durability and image quality of the photoconductor. And since the intensity | strength of convex part itself is large, there exists resistance with respect to a cleaning blade. It is preferable that the cross-linked product of the charge mailing compound at the convex portion has a high cross-linking density so as not to be dissolved in a solvent such as tetrahydrofuran or toluene. That is, it is necessary to form a convex portion that can withstand the frictional force of the cleaning blade. The cleaning blade is generally made of a hard rubber-like elastic body such as polyurethane and has a plate shape. For example, a case where this is brought into contact with the surface of the photoreceptor in the counter direction will be described. The transfer residual toner is cleaned by sliding on the surface of the photoconductor. At this time, it is said that the tip of the cleaning blade is causing fine vibrations (stick sticks) due to friction with the surface of the photoconductor. The vibration state changes depending on the characteristics of the photosensitive member and the surface condition of the photoreceptor. It is considered preferable for cleaning that the fine vibrations continue stably. In the present invention, it is considered that it also has the effect of promoting fine vibrations. The tip of the cleaning blade is configured to be continuously stabilized.

  The shape of the convex portion on the surface of the photoreceptor of the present invention can be measured using a known laser microscope, optical microscope, electron microscope, or atomic force microscope. For example, an ultra-deep shape measuring microscope VK-8550 manufactured by Keyence Corporation, a surface shape measuring system Surface Explorer SX-520DR model manufactured by Ryoka System Co., Ltd., a scanning confocal laser microscope OLS3000 manufactured by Olympus, etc. are used as laser microscopes. it can. As an optical microscope, a digital microscope VHX-500 manufactured by Keyence Corporation and a 3D digital microscope VC-7700 manufactured by OMRON Corporation can be used. As the electron microscope, a 3D real surface view microscope VE-9800 manufactured by Keyence Corporation and a scanning electron microscope SUPERSCAN SS-550 manufactured by Shimadzu Corporation can be used. As an atomic force microscope, a nanoscale hybrid microscope VN-8000 manufactured by Keyence Corporation and a scanning probe microscope SPM-9600 manufactured by Shimadzu Corporation can be used. Using these microscopes, it is possible to observe and measure the shape of the convex portion, the state of the skirt, the arrangement, the height, or the top.

<Method of forming convex portions on the surface of the photoreceptor>
The method for forming the convex portion is not particularly limited as long as the method can satisfy the requirements for the convex portion described above. For example, there is a spray coating method in which a convex liquid is formed by spraying a coating liquid having a composition for forming a convex shape onto a surface of an electrophotographic photosensitive member from a spray gun. The spray method will be described below.

A known spray processing (coating) method can be used. FIG. 5 shows an outline of the spray coating apparatus. The photosensitive drum is rotated at a predetermined speed by a rotation driving device (not shown). Next, while supplying the coating liquid and gas to the moving application body having a spray gun at a predetermined pressure, the coating liquid and the gas are oscillated (moved) in the axial direction of the photosensitive drum, and the sprayed coating liquid is sprayed on the photosensitive drum. A coating film can be formed.
Basic coating conditions are the viscosity, solvent and concentration of the coating solution, and the rotational speed of the photoreceptor, the oscillating speed, the form of the discharge port of the spray gun, the pressure of the supplied gas, and the flow rate.

  A known method can be used as a method of forming by ink jet. FIG. 6 shows an outline of an inkjet coating apparatus. Basically, the spray gun of the spray coating apparatus (1) can be used in place of the inkjet head. The photosensitive drum is rotated at a predetermined speed by a rotation driving device (not shown). Next, while supplying the convex portion forming coating liquid to the inkjet head attached to the movable coating body, the liquid is oscillated (moved) in the axial direction of the photosensitive drum, and the droplet fine particles of the convex portion forming coating liquid are exposed to light. A plurality of convex portions having desired convex portions and their arrangements and skirt portions can be formed on the surface of the photoconductor.

<Electrophotographic photoreceptor>
The photoreceptor of the present invention has at least a support and an organic photosensitive layer (hereinafter also simply referred to as “photosensitive layer”) provided thereon, and further provided thereon for durability. It has a cross-linked surface layer, and a number of cross-linked convex portions are provided on the cross-linked surface layer.

  The photosensitive layer may be a single-layer type photosensitive layer or a laminated type photosensitive layer in which a charge generation layer and a charge transport layer are laminated. The former contains the charge transport material and the charge generation material in the same layer. The latter is functionally separated into a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material. The electrophotographic photoreceptor according to the present invention is preferably a laminated photosensitive layer. In addition, the laminated type photosensitive layer is a reverse layer type in which the charge transport layer and the charge generation layer are laminated in this order from the support side, even if it is a normal layer type photosensitive layer in which the charge generation layer and the charge transport layer are laminated in this order from the support side. It may be a photosensitive layer. This is shown in FIG. 7, FIG. 8, and FIG.

1. Support As the support, a known material showing conductivity can be used. For example, a support made of metal such as iron, copper, gold, silver, aluminum, zinc, titanium, lead, nickel, tin, antimony, indium, chromium, aluminum alloy, and stainless steel can be used. Further, the above-mentioned metal support or plastic support having a layer formed by vacuum deposition of aluminum, an aluminum alloy, or an indium oxide-tin oxide alloy can also be used. Also, use 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 together with a binder resin, or a plastic support having a conductive binder resin. You can also.
The surface of the support may be subjected to cutting treatment, roughening treatment, and alumite treatment for the purpose of preventing interference fringes (moire) caused by laser light used for image exposure.

2. Blocking layer A charge injection preventing layer (blocking layer) having a barrier function or an adhesive function may be provided between the support and the undercoat layer. The blocking layer is formed for improving the charge injection property from the support and protecting the photosensitive layer from electrical breakdown.
Materials for the blocking layer include the following: polyvinyl alcohol, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide, N-methoxymethylated 6 nylon, co There are polymerized nylon and the like. The blocking layer can be formed by applying a coating solution obtained by dissolving these materials in a solvent and drying it.
The thickness of the blocking layer is preferably 0.05 μm or more and 7 μm or less, and more preferably 0.1 μm or more and 2 μm or less.

3. Undercoat layer An undercoat layer may be provided between the support and the photosensitive layer for the purpose of preventing interference fringes (moire) caused by laser light or covering the support.
The undercoat layer may be formed using a conductive layer coating liquid in which carbon black, fine particles having moderate conductivity, or a pigment is contained in a binder resin. You may add the compound which hardens | cures or bridge | crosslinks to the coating liquid for conductive layers. Furthermore, the surface of the undercoat layer may be roughened.
The thickness of the undercoat layer is preferably 0.2 μm or more and 20 μm or less, and preferably 5 μm or more and 10 μm or less.

  Known binder resins can be used for the undercoat layer. For example: polymers / copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, vinylidene fluoride, trifluoroethylene, polyvinyl alcohol, polyvinyl acetal, polycarbonate, polyester, polysulfone, polyphenylene Examples include oxide, polyurethane, cellulose resin, phenol resin, melamine resin, silicon resin, and epoxy resin.

  Conductive fine particles or pigments, particles of metals (alloys) such as aluminum, zinc, copper, chromium, nickel, silver, and stainless steel; those deposited on the surface of plastic particles. Further, particles of zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony or tantalum-doped tin oxide metal oxide particles may be used. These may be used alone or in combination of two or more. When two or more types are used in combination, they may be simply mixed, or may be in the form of a solid solution or fusion.

4). Photosensitive Layer The photosensitive layer in the present invention is preferably a laminated photosensitive layer in which a charge generation layer and a charge transport layer are sequentially laminated.
(Charge generation layer)
Of the layers in the multilayer photoconductor, the charge generation layer 25 will be described. The charge generation layer refers to a part of the laminated photosensitive layer and has a function of generating charges by exposure. This layer is mainly composed of a charge generating substance among the contained compounds. For the charge generation layer, a binder resin may be used as necessary. As the charge generation material, inorganic materials and organic materials can be used.

  Examples of the inorganic material include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compound, and amorphous silicon. In amorphous silicon, a dangling bond that is terminated with a hydrogen atom or a halogen atom, or a material that is doped with a boron atom or a phosphorus atom is preferably used.

  On the other hand, as the organic material, known materials can be used, for example, metal phthalocyanine such as titanyl phthalocyanine and chlorogallium phthalocyanine, metal-free phthalocyanine, azulenium salt pigment, squaric acid methine pigment, symmetrical type having a carbazole skeleton. Alternatively, an asymmetric azo pigment, a symmetric or asymmetric azo pigment having a triphenylamine skeleton, a symmetric or asymmetric azo pigment having a fluorenone skeleton, a perylene pigment, and the like can be given. Among these, metal phthalocyanines, symmetric or asymmetric azo pigments having a fluorenone skeleton, symmetric or asymmetric azo pigments having a triphenylamine skeleton, and perylene pigments have a high quantum efficiency of charge generation, and thus are suitable for the present invention. It is suitable as a material to be used. These charge generation materials may be used alone or as a mixture of two or more.

  The binder resin used as necessary for the charge generation layer includes polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, polyarylate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-. Examples thereof include vinyl carbazole and polyacrylamide. Moreover, the polymeric charge transport material mentioned later can also be used. Of these, polyvinyl butyral is often used and is useful. These binder resins may be used alone or as a mixture of two or more.

Methods for forming the charge generation layer are roughly classified into a vacuum thin film preparation method and a casting method from a solution dispersion system.
Examples of the former method include a vacuum deposition method, a glow discharge decomposition method, an ion plating method, a sputtering method, a reactive sputtering method, and a CVD (chemical vapor deposition) method. Can be formed satisfactorily.
In addition, in order to provide the charge generation layer by the casting method, the above-described inorganic or organic charge generation material may be combined with a binder resin, if necessary, using a solvent such as tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, butanone, ball mill, attritor. The dispersion may be dispersed by a sand mill or the like, and the dispersion may be diluted appropriately. Among these solvents, methyl ethyl ketone, tetrahydrofuran, and cyclohexanone are preferable because they have a lower environmental impact than chlorobenzene, dichloromethane, toluene, and xylene. The coating can be performed by a dip coating method, a spray coating method, a bead coating method, or the like.

The thickness of the charge generation layer provided as described above is usually about 0.01 to 5 μm.
When it is necessary to reduce the residual potential and increase the sensitivity, these characteristics are often improved by increasing the thickness of the charge generation layer. On the other hand, the chargeability often deteriorates, such as the charge charge retention and space charge formation. From these balances, the thickness of the charge generation layer is more preferably in the range of 0.05 to 2 μm.

  Further, if necessary, low-molecular compounds such as antioxidants, plasticizers, lubricants and ultraviolet absorbers and leveling agents described later can be added to the charge generation layer. These compounds can be used alone or as a mixture of two or more. When a low molecular weight compound and a leveling agent are used in combination, sensitivity deterioration often occurs. For this reason, the amount of these used is generally 0.1 to 20 phr, preferably 0.1 to 10 phr, and the amount of the leveling agent used is suitably about 0.001 to 0.1 phr.

(Charge transport layer)
The charge transport layer refers to a part of the laminated photosensitive layer that functions to inject and transport charges generated in the charge generation layer and to neutralize the surface charge of the photoreceptor provided by charging. The main component of the charge transport layer can be said to be a charge transport component and a binder component that binds the charge transport component.
Examples of materials that can be used for the charge transport material include low molecular weight electron transport materials, hole transport materials, and polymer charge transport materials.
Examples of the electron transporting material include electron accepting materials such as asymmetric diphenoquinone derivatives, fluorene derivatives, and naphthalimide derivatives.
These electron transport materials may be used alone or as a mixture of two or more.

As the hole transport material, an electron donating material is preferably used.
Examples thereof include oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, butadiene derivatives, 9- (p-diethylaminostyrylanthracene), 1,1-bis- (4-dibenzylaminophenyl) propane, Examples include styryl anthracene, styryl pyrazoline, phenylhydrazones, α-phenyl stilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, and thiophene derivatives.
These hole transport materials may be used alone or as a mixture of two or more.

  Moreover, the polymeric charge transport material represented below can be used. For example, a polymer having a carbazole ring such as poly-N-vinylcarbazole, a polymer having a hydrazone structure exemplified in JP-A-57-78402, etc., exemplified in JP-A-63-285552, etc. The polysilylene polymer to be used, and aromatic polycarbonates exemplified by general formula (1) to general formula (6) of JP-A No. 2001-330973. These polymer charge transport materials can be used alone or as a mixture of two or more. In particular, the exemplified compounds disclosed in JP-A-2001-330973 are useful because of their good electrostatic characteristics.

  When a polymer charge transport material is laminated on a crosslinkable resin surface layer, compared to a low molecular charge transport material, there is less oozing of the components constituting the charge transport layer into the crosslinkable resin surface layer, and the crosslinkable resin surface It is a material suitable for preventing poor curing of the layer. In addition, since the charge transport material has high heat resistance due to the high molecular weight, there is little deterioration due to the heat of curing when forming the cross-linked resin surface layer.

Examples of the polymer compound that can be used as the binder component of the charge transport layer include polystyrene, polyester, polyvinyl, polyarylate, polycarbonate, acrylic resin, silicone resin, fluorine resin, epoxy resin, melamine resin, urethane resin, and phenol resin. And thermoplastic or thermosetting resins such as alkyd resins. Of these, polystyrene, polyester, polyarylate, and polycarbonate are useful because many of them have good charge transfer characteristics when used as a binder component of a charge transport component. Further, since the charge transport layer has a cross-linked resin surface layer laminated thereon, the charge transport layer is not required to have mechanical strength as compared with the conventional charge transport layer. For this reason, a material such as polystyrene, which is highly transparent but has a low mechanical strength and is difficult to apply in the prior art, can be effectively used as the binder component of the charge transport layer.
These polymer compounds can be used singly or as a mixture of two or more kinds, or as a copolymer composed of two or more kinds of these raw material monomers, and further copolymerized with a charge transport material.

When an electrically inactive polymer compound is used for modifying the charge transport layer, a cardo polymer type polyester having a bulky skeleton such as fluorene, a polyester such as polyethylene terephthalate or polyethylene naphthalate, or a C type polycarbonate is used. Polycarbonate in which the 3,3 ′ portion of the phenol component is alkyl-substituted with respect to a bisphenol-type polycarbonate, polycarbonate in which the geminal methyl group of bisphenol A is substituted with a long-chain alkyl group having 2 or more carbon atoms, biphenyl or biphenyl Polycarbonate having an ether skeleton, polycarbonate having a long chain alkyl skeleton such as polycaprolactone and polycaprolactone (for example, described in JP-A-7-292095), acrylic resin, polystyrene, hydrogenated porcine Diene is effective.
Here, the electrically inactive polymer compound refers to a polymer compound that does not include a chemical structure exhibiting photoconductivity such as a triarylamine structure.
When these resins are used in combination with a binder resin as an additive, the addition amount is preferably 50 wt% or less with respect to the total solid content of the charge transport layer due to restrictions on light attenuation sensitivity.

  When a low molecular charge transport material is used, the amount used is 40 to 200 phr, preferably about 70 to 100 phr. When a polymer charge transport material is used, a material in which the resin component is copolymerized in an amount of about 0 to 200 parts by weight, preferably about 80 to 150 parts by weight with respect to 100 parts by weight of the charge transport component is preferably used.

When two or more kinds of charge transport materials are contained in the charge transport layer, it is preferable that the difference in ionization potential is small. Specifically, by setting the difference in ionization potential to 0.10 eV or less, Can be prevented from becoming a charge trap of the other charge transport material.
Regarding the relationship between the ionization potentials, the difference between the charge transporting material contained in the charge transporting layer and the curable charge transporting material described later is preferably 0.10 eV.
In addition, the ionization potential value of the charge transport material in the present invention is a numerical value obtained by measuring by a general method using the atmospheric atmospheric ultraviolet photoelectron analyzer AC-1 manufactured by Riken Keiki Co., Ltd.

  In order to satisfy high sensitivity, the charge transport component is preferably added in an amount of 70 phr or more. In addition, α-phenylstilbene compounds, benzidine compounds, butadiene compound monomers, dimers, and polymer charge transport materials having these structures in the main chain or side chain are materials having high charge mobility. Many are useful.

  Examples of the dispersion solvent that can be used in preparing the charge transport layer coating material include ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, and cyclohexanone, ethers such as dioxane, tetrahydrofuran, and ethyl cellosolve, and aromatics such as toluene and xylene. , Halogens such as chlorobenzene and dichloromethane, and esters such as ethyl acetate and butyl acetate. Of these, methyl ethyl ketone, tetrahydrofuran, and cyclohexanone are preferable because they have a lower environmental impact than chlorobenzene, dichloromethane, toluene, and xylene. These solvents can be used alone or in combination.

  The charge transport layer can be formed by dissolving or dispersing a mixture or copolymer mainly composed of a charge transport component and a binder component in an appropriate solvent, and applying and drying the mixture. As the coating method, a dipping method, a spray coating method, a ring coating method, a roll coater method, a gravure coating method, a nozzle coating method, a screen printing method, or the like is employed.

Since the cross-linked resin surface layer is laminated on the upper layer of the charge transport layer, the thickness of the charge transport layer in this configuration is designed to increase the thickness of the charge transport layer in consideration of film scraping in actual use. It is unnecessary.
The film thickness of the charge transport layer is practically about 10 to 40 μm, more preferably about 15 to 30 μm for the purpose of ensuring the required sensitivity and charging ability.

  If necessary, low-molecular compounds such as antioxidants, plasticizers, lubricants and ultraviolet absorbers and leveling agents described later can be added to the charge transport layer. These compounds can be used alone or as a mixture of two or more. When a low molecular weight compound and a leveling agent are used in combination, sensitivity deterioration often occurs. For this reason, the amount of these used is generally 0.1 to 20 phr, preferably 0.1 to 10 phr, and the amount of the leveling agent used is suitably about 0.001 to 0.1 phr.

5). Cross-linked surface layer The electrophotographic photosensitive member of the present invention includes a surface layer integrated with a plurality of convex portions.
In the present invention, the surface layer represents a specially provided layer containing a crosslinked body on the outermost surface of the photoreceptor in addition to the photosensitive layer.

The present invention is differentiated from the conventional addition of filler to the binder resin and the following points.
That is, when the filler is dispersed only in the paint of the cross-linked resin surface layer and this paint is coated on the electrophotographic photosensitive member, the coating takes an aggregate structure in the binder resin, and the coating structure depends on the aggregate structure. Uneven portions are formed on the surface of the electrophotographic photosensitive member.

  On the other hand, in the present invention, for example, after a cured film is provided on the surface of the electrophotographic photosensitive member, a paint is sprayed again to form a convex factor on the surface of the electrophotographic photosensitive member. Silicone oil is unevenly distributed on the surface of the cured film, so that the wettability with respect to the paint is poor, and the paint sprayed again is cured in the form of droplets on the surface of the photoreceptor. For this reason, it becomes possible to distinguish the shape of a convex part from the wave | undulation of a foundation | substrate. This is a property that cannot be obtained when a film is formed by dispersing a filler in the paint. This is because the paint has a leveling action.

  A known charge transporting compound can be used as the charge transporting material contained in the surface layer integrated with the convex portion. Examples of the polymerizable or crosslinkable monomer or oligomer include a chain polymerization compound having an acryloyloxy group and a styrene group, and a sequential polymerization compound having a hydroxyl group, an alkoxysilyl group, and an isocyanate group. From the viewpoint of the obtained electrophotographic characteristics, versatility, material design, and production stability, a combination of a hole transporting compound and a chain polymerization material is preferable. Furthermore, both a hole transporting group and an acryloyloxy group are included in the molecule. Particularly preferred is a system in which a compound having a crosslinking is crosslinked. It can be crosslinked and cured using heat, light and radiation. The crosslinkable resin is preferably three-dimensionally crosslinked. The resin is not only strengthened by crosslinking.

(Binder material composition of the cross-linked surface layer)
In the present invention, the charge transport layer itself having a convex portion can be composed of a crosslinked or cured resin. Similarly, a resin crosslinked or cured in the second charge transport layer having a convex portion on the charge transport layer can be used. As a composition of a material that can be polymerized or cross-linked, a compound having a charge transport structure and having at least one (meth) acryloyloxy group can be used. Alternatively, the composition may be combined with a monomer or oligomer having one or more (meth) acryloyloxy groups not including a charge transport structure. A surface layer having convex portions can be formed by containing such a compound in at least the coating liquid, and can be crosslinked and cured by applying energy by heat, light, or radiation such as an electron beam or γ-ray. The crosslinked product of the charge transporting compound preferably has a triarylamine structure. For example, a charge transporting compound represented by the following general formula 1 can be mentioned.

(Wherein, d, e and f are each an integer of 0 or 1, R ₁₃ represents a hydrogen atom or a methyl group, R ₁₄ and R ₁₅ represent a substituent other than a hydrogen atom and an alkyl group having 1 to 6 carbon atoms. And may be different from each other, g and h each represent an integer of 0 to 3. Z is a single bond, a methylene group, an ethylene group,
Or
Represents. )

Illustrative compounds are listed.
2- [4 '-(Di-p-tolyl-amino) -biphenyl-4-yl] -ethyl acrylate

Acrylic acid 2- [4 ′-(di-p-tolyl-amino) -biphenyl-4-yl]

  Among charge transporting compounds having radical polymerizability, a compound having a structure represented by the above general formula 1 is advantageous for increasing the sensitivity of an electrophotographic photoreceptor. Among many compounds, the structure of the general formula 1 is excellent in curability inside the film and is extremely advantageous.

  In the case of the charge transport layer, the thickness of the crosslinked resin layer is preferably 5 μm or more and 50 μm or less, and more preferably 10 μm or more and 35 μm or less. In the case of the second charge transport layer or protective layer, the thickness is preferably 0.1 μm or more and 20 μm or less, and more preferably 1 μm or more and 10 μm or less. In the present invention, if there are a plurality of convex portions on the surface of the electrophotographic photosensitive member, the film thickness may not be uniquely defined. Therefore, an eddy current type film thickness meter (Fischer, mms) less affected by the convex portions. It is defined by the average value of any five locations in the axial direction of the electrophotographic photosensitive member.

  As described above, the electrophotographic photosensitive member of the present invention has a plurality of specific convex portions formed on the surface of the electrophotographic photosensitive member excellent in wear resistance. The conventional electrophotographic photosensitive member having a wear-resistant surface results in less film scraping on the surface of the electrophotographic photosensitive member, the surface is not renewed, foreign matter and contaminants accumulate, the blade is difficult to slip, chattering, twisting, This is a solution to the deterioration of the cleaning property and the occurrence of image defects caused by reversal or the like by improving the surface of the electrophotographic photosensitive member.

(2) Cleaning Blade The cleaning blade used in the present invention is housed in a cleaning device provided in an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a printing machine, and a toner image is contained in the image forming apparatus. It is located between the transfer device and the charging device corresponding to the transfer. That is, the toner remaining after transferring the visualized image (toner image) obtained by developing the electrostatic latent image formed on the photosensitive member by charging and image exposure with a developer onto a transfer material such as copy paper This is a module for removing residual powder such as paper powder and paper dust from the photoreceptor. In addition to the cleaning blade, a cleaning brush may be provided in the cleaning device.

In order to maintain good cleaning performance over a long period of time using the cleaning blade, the following points 1) to 3) are important.
1) A sufficient uniform and uniform contact between the photosensitive member and the cleaning blade is ensured.
2) The frictional resistance when the cleaning blade is in contact is reduced to such an extent that it does not interfere with cleaning. That is, the frictional resistance of the portion where the cleaning blade is in sliding contact with the photosensitive member is reduced so that the blade is not distorted or chattered.
3) The frictional resistance reducing means is stably maintained over a long period of time.

An example of the configuration of the cleaning blade is shown in FIGS.
In the cleaning blade 71 of the present invention, a blade 71d is fixed to a support 71a supported in a cantilever shape, and a hard coat material 71e is applied to the edge of the blade 71d over the longitudinal direction of the blade 71d. .
For the support 71a, a material that does not vibrate or is difficult to slide even when slidably contacted with the photoreceptor 1, and a material having an appropriate thickness are used. As a material, a metal such as an iron plate, aluminum, or stainless steel or a metal alloy is used, and a thickness of about 2 to 5 mm can be used although the thickness varies depending on the material. In addition, a damping member can be used for the side surface of a support body as needed.

  The shape of the support 71a can be a U-shaped holder as shown in FIG. 10 (integral structure or a combination of two types of members), or an L-shape as shown in FIG. Further, although not shown in the figure, a plate or the like simply cut into a rectangle is used. A mounting hole 71b and a positioning hole 71c are provided in the support, and are screwed to the mounting position of the process cartridge and the cleaning device unit to be supported in a cantilever shape, and the blade 71d is positioned at the free end. .

  As the material of the cleaning blade 71d used in the present invention, flexible urethane rubber (or polyurethane rubber) is suitable. The thickness of the urethane rubber used as the cleaning member is determined by mechanical durability, pressing strength against the photosensitive member, an area in which the toner is sandwiched between the photosensitive member 1 (smaller is preferable), and the like.

  On the other hand, it is desirable that the edge of the cleaning blade 71 is in line contact as much as possible in order to perform cleaning well. However, if a defect occurs in the blade edge, there is an increased risk of defective cleaning. When (contact pressure) is applied, the blade needs to bend to some extent. That is, the blade needs to be urethane rubber having an appropriate hardness. The rubber hardness is preferably 60 ° to 85 ° in terms of JIS-A hardness. Below 60 °, the bending becomes large, the toner is pressed against the photosensitive member, the blade edge is lifted, the toner is submerged under the blade, and the cleaning is liable to occur. On the other hand, when the angle is 85 ° or more, the line contact is good and good cleaning properties are exhibited in the initial stage. However, when the blade edge is lost, the toner cleaning margin becomes low and the toner slips easily.

Urethane rubber has several excellent properties such as excellent ozone resistance, high mechanical durability, little change over time such as hardness, and excellent cleaning properties. However, when used as a cleaning member for an organic photoreceptor, particularly a cross-linked resin surface layer, the frictional resistance is extremely high.
For this reason, when used as it is, the edge portion of the cleaning blade is excessively drawn in the driving direction of the photosensitive member, and the toner easily slips through. In particular, this margin is small for the use of polymerized toner, which is a new problem.

  On the other hand, it is extremely advantageous to provide a hard coat material at the edge portion of the cleaning blade. As a result, the pull-in of the edge portion of the blade is reduced, and wear of the edge portion can be suppressed, and stable cleaning performance can be imparted to the electrophotographic apparatus over a long period of time.

  Examples of the hard coat material include those described in Kenji Kushi, Painting Technology, 70-74, 1996 (2). In this article, the coating material by thermosetting method includes paints based on alkoxysilane and carbon functional silane, paints that form cross-linked bodies by dehydration or deformalization of methylolmelamine, and urethane bonds by polyisocyanate and polyol. Examples thereof include paints to be produced and colloidal silica paints. Examples of the coating material obtained by the active energy ray curing method include a paint mainly composed of a polyfunctional acrylate having an acryloyloxy group or a methacryloyloxy group, and a paint having an unsaturated bond such as a vinyl group or an allyl group.

  A desirable thickness of the hard coat resin layer provided on the edge of the cleaning blade is 1 μm to 50 μm. If it is smaller than 1 μm, in terms of mechanical durability, if it is thicker than 50 μm, the hard coating layer at the edge of the cleaning blade becomes too rigid to follow the elasticity of the elastomer of the base material, and cracks and cracks occur. This is likely to occur and increases the possibility of defective cleaning.

On the other hand, the combined use of the cleaning blade provided with the hard coat resin layer at the edge portion and the electrophotographic photosensitive member provided with the cross-linked resin surface layer causes the generation of rubbing noise (blade squeal) as described above. Therefore, in order to maintain good image formation and avoid discomfort due to blade noise, it is necessary to take measures to reduce blade noise on either the photoreceptor or the blade 71d or both.
On the other hand, the application of the electrophotographic photosensitive member having the convex shape of the present invention is extremely important.

As a means for applying the hard coat resin layer, there are a spray coating method, a dipping coating method, a nozzle coating method, and the like, and any method can be used for the cleaning blade of the present invention.
In the case of the spray coating method, in order to prevent the hard coating paint 71e from being attached to an unnecessary surface, a seal is applied and sprayed to the surface that is not applied.
In the case of the dipping coating method, the surface facing the photoconductor is faced up, and only the edge portion is dipped or immersed on each side (in the case of double-sided coating). In this case as well, a seal is applied as necessary. Thereafter, the surface facing the photoconductor is faced up and dried at a temperature of normal temperature to 40 ° C., dried to some extent, and then heated and dried at a temperature of 100 to 150 ° C. for 20 to 40 minutes, or UV light or an electron beam. Irradiating active energy rays such as.

  In FIG. 12 and FIG. 1, symbol L1 indicates the coating width, and the coating width L1 only needs to be wide enough for the side surface of the blade to rub against the photosensitive member when it contacts the photosensitive member. Considering the properties and the like, it is sufficient to have 2 mm or more. When the cleaning blade 71 is in operation, a load (contact pressure) of about 25 (g / cm) is applied, so that the cleaning blade comes into contact with the photoreceptor with bending (deflection).

  The tip portion including the edge of the cleaning blade has a lower frictional resistance as the surface contact width is smaller. Therefore, the cleaning blade 71 is more convenient for cleaning by the line contact, but in practice, the surface contact is slightly smaller. In contact. It is necessary that the paint is applied to the surface contact portion. As a result, the frictional resistance with the photosensitive member is reduced.

  The desired effect can be achieved by simply applying the hard coat resin layer to one side via the edge line of the edge part of the blade 71d, but the mechanical strength of the blade 71d can be achieved by applying the hard coat resin layer to both surfaces centering on the edge line of the blade edge part. It is useful because it can also be improved.

In order to reduce the frictional resistance with the photoreceptor 1 and increase the effectiveness, it is important that the applied coating film has as little gap as possible on the photoreceptor. That is, it is desirable that the 10-point average roughness Rz is 3 μm or less and the maximum height Rmax is 5 μm or less.
Although the above numerical value is equal to or larger than the toner diameter to be used, the blade 71d is placed so as to be in contact with the photoconductor with a load (contact pressure) applied. Becomes smaller than the toner diameter, and the toner does not slip through.
However, when the side surface of the blade is rubbed, scratches in the deep groove of the photosensitive member or defects on the blade edge may cause a defective cleaning, so the values are within the above values. Preferably, the coating is performed so that Rz is 2 μm or less and Rmax is 3 μm or less.
The measured value is a numerical value at a sweep width of 2.5 mm using Surfcom 1400D of Tokyo Seimitsu Co., Ltd., pickup: E-DT-S02A) (JIS D0601 (1982)).

The cleaning blade 71 includes a spring method that uses a spring to press the blade edge against the photosensitive member, and a fixing method, and a fixing (non-moving) method is preferable.
In the case of the spring method, even if the blade edge is worn, the contact pressure can follow the surface of the photosensitive member and the contact pressure can be made almost constant. There is a tendency to be a little weak in toner stopping power. On the other hand, when the blade edge is worn, the contact pressure may change (become light), but it is difficult to vibrate, so it has a strong tendency to prevent the toner from getting in and maintains the cleaning performance. Is advantageous. In the case of the fixing method, if the strength of the mounting unit is weak, the performance is not sufficiently exerted. Therefore, it is desirable that the sliding movement including the blade 71d is difficult to make a slight movement when the photosensitive member is rubbed. That is, the attachment portion of the cleaning blade 71 is set to have sufficient strength. If the toner blocking power is high, the wear of not only the blade but also the photoconductor is reduced, so that it is considered that the fixed type is superior in terms of durability.

  As shown in FIG. 14, the contact with the photosensitive member when the cleaning blade 71 is attached is a counter contact. The contact angle θ with respect to the photosensitive member is important for maintaining good cleaning performance. The contact angle θ of the cleaning blade 71 used in the present invention cannot be small or large. When the angle is small, the toner is easy to slip through. When the angle is large, the toner enters the surface of the blade 71d facing the photoconductor, the blade floats, which causes a cleaning failure and a filming phenomenon. Therefore, it is desirably 15 ° to 30 °, preferably 18 ° to 22 °.

  On the other hand, the contact pressure is 15 to 35 (g / cm). When the contact pressure is low, the toner blocking efficiency decreases when the photosensitive member or blade edge is damaged or when it is formed, and the toner enters under the blade, so that the blade and the photosensitive member are accelerated. On the other hand, if the contact pressure is high, the gap between the photoconductor and the blade is suppressed and the cleaning performance is improved. However, the photoconductor and the blade are burdened, and the durability is reduced, leading to a reduction in the cleaning performance. . Therefore, it is necessary to set the contact pressure to a suitable value. However, a preferable contact pressure is 15 to 35 (g / cm), and preferably 20 to 25 (g / cm).

  When it is 15 g / cm or less, characteristics such as the smoothness, circularity, and vibration of the photoreceptor become important, unevenness of the adhesion of the blade edge to the photoreceptor occurs, and the belt is poorly cleaned in an area where the adhesion is insufficient. Is more likely to happen.

  On the other hand, when the load is increased, the above-described problems occur. However, as 35 g / cm or more is increased, the frictional resistance between the photosensitive member and the cleaning blade becomes more involved. As a result, the blade edge 71f is swung, the blade squeals, etc., and the wear of the photosensitive layer is accelerated accordingly. Therefore, it is necessary to set the contact pressure so that a good balance can be maintained not only with respect to the toner cleaning property but also with respect to the durability of the photosensitive member and the cleaning blade.

(3) Cleaning Device, Image Forming Apparatus, and Process Cartridge FIG. 15 is a schematic view showing an example of an image forming apparatus using electrophotography. In the figure, a charging device 2 is disposed opposite to the photoreceptor 1.
The charging device 2 in the image forming apparatus shown in FIG. 16 is a contact charging method using a roller type charging device. In the present invention, the charging device 2 includes a corona charging device, a contact charging device, a proximity charging device (non-contact charging). Any charging device can be used. However, in the present invention, compared with the corona charging device, the installation space is small, the generation of ozone is as small as 0.1 to 0.3 ppm, the high-voltage power source can be made smaller, and the contact charging is excellent in energy saving, resource saving and environmental performance. Method and proximity charging method are preferable.

  The proximity charging method is a method in which charging is performed in contact with a photoreceptor. On the other hand, in the proximity charging method, the charging member and the photosensitive member are charged with a distance of several tens of μm. Since both are charging methods with discharge, ozone is generated, but as described above, ozone generation is extremely small and the charging method is environmentally friendly.

The contact charging method has less margin for toner contamination and discharge destruction of the charging member than the non-contact charging method, but the applied voltage can be set lower because Gap is 0 μm. Therefore, the production amount of corona products such as ozone and NOx is reduced.
In the case of the proximity charging method, since the charging member is separated from the photosensitive member, wear caused by the charging member is reduced, and when toner is removed from the cleaning blade, toner contamination on the charging member is reduced and discharge is caused. The margin for destruction increases.

  In the contact charging or proximity charging method, a DC voltage or a DC voltage superimposed on an AC voltage is applied to the charging member. Both contact charging and non-contact charging are performed according to Paschen's law, and the charging start voltage Vth is the lowest during contact charging, and the starting voltage Vth increases as Gap increases. In order to set the charging voltage of the photoreceptor 1 to −400 to −800 V, a DC voltage of −1000 V to −2000 V is applied, or a DC voltage of −450 to −900 V is applied to an AC voltage of 700 V to 2000 V / 800 to 4500 Hz. (Sine wave, triangular wave) are superimposed and applied. The AC voltage is superimposed in order to prevent uneven charging when there is a gap between the photosensitive member and the charging member, and to prevent image unevenness, which is equal to the charging voltage necessary for image formation, or The DC voltage is set to a slightly higher DC voltage by superimposing an AC voltage of a Peak to Peak voltage that is at least twice the charging start voltage Vth.

The roller charging member is covered with an elastic member using a SUS round bar of φ5 to φ15 (mm) as a core metal. For elastic members that charge the photoconductor, resistance control materials such as conductive carbon, carbon fiber powder, and ionic conductive agent are added to epichlorohydrin rubber alone or urethane rubber or epichlorohydrin rubber. In which the specific resistance is adjusted to 10 ⁵ to 10 ¹⁴ (Ω · cm) is used. Specifically, the electric resistance of the surface facing the photoconductor between the contact charging member and the non-contact charging member can be changed depending on the charging method.
In the non-contact charging member, the outermost layer surface is set to 10 ⁵ to 10 ⁸ (Ω · cm), and in the case of the contact charging member, 10 ¹² to 10 ¹⁴ (Ω · cm). This is because there is a gap between the charging member and the photosensitive member, so that the charging start voltage Vth shifts to the higher side and the charging property is different. Therefore, in order to perform uniform charging, the volume resistance of the charging member needs to be lowered. There is. However, if it is lowered too much, it causes discharge breakdown, so it is desirable that it is 10 ⁵ Ω · cm or more.

Further, the surface roughness of the charging member is more advantageous for improving uniform charging and charging efficiency when the 10-point average roughness Rz is about 50 to 200 (μm) than the contact charging member. The hardness is an elastic member having a JIS-A hardness of about 30 to 90 degrees.
In the case of the contact charging method, in order to increase the charging efficiency, it is desirable to have a large nip (contact width when the photosensitive member and the photosensitive member are in contact) (1 to 5 mm). Although a member is used, in the case of a non-contact charging member, the charging efficiency deteriorates because the nip cannot be obtained, but there is an advantage that the hardness of the charging member used is not limited.

The photoreceptor 1 uniformly charged by the charging device 2 is then irradiated with image information of a dot pattern of light that is output from the image exposure device 3 using the LD element or LED element array as a light source. As a result, an electrostatic latent image having a light / dark potential difference is formed on the photoreceptor 1. The light / dark potential difference is preferably at least 250 V or more, and is usually preferably 350 to 600 (V).
The electrostatic latent image is developed by the developing device 4 and visualized as a toner image. The developer used for development includes a one-component system and a two-component system, but it is advantageous to use a two-component developer in order to obtain a high-resolution image quality. The two-component developer is composed of toner and magnetic powder called a carrier.

  Carrier is made of magnetic powder such as iron, ferrite, nickel (magnetic powder), resin such as polyfluorinated carbon, polyvinyl chloride, polyvinylidene chloride, etc. to improve chargeability, charging stability, durability, etc. The coated one is used, and the average particle size of the carrier is about 40 to 80 μm.

  The toner includes a pulverized toner obtained by a mechanical pulverization method and a polymerized toner produced chemically. Although the pulverized toner has also been described in the background art, it is said that the pulverized toner is advantageous for cleaning because it has an irregular shape (average circularity is around 0.9). However, because the shape and particle size are not uniform, transfer efficiency and development fidelity are a little inferior. In addition, toner with a small particle size is included, and it is easy to break. (Lines are not beautiful lines but are cut off, and light and dirty noise is generated). Therefore, although there is an insufficient surface for a high-quality image with higher resolution, the resolution of 6.3 to 8 (lines / mm) is sufficiently resolved, and there is no problem in general image quality.

On the other hand, there are suspension polymerization method, dispersion polymerization method, emulsion polymerization method, microcapsule polymerization method, spray drying and the like as means for producing the polymerized toner. For example, in the case of suspension polymerization, the binder resin is produced by homogenizing an additive such as a colorant or a charge control agent, and adding a dispersion medium and a dispersant to polymerize the binder resin. Since the process of the polymerization method is simplified, the manufacturing cost is lower than that of the pulverization method. Moreover, the particle diameters are relatively well aligned, almost spherical (average circularity of 0.95 to 0.995), and the particle diameters are approximately uniform.
Therefore, it is easy to align the charges uniformly, the image is developed almost faithfully to the latent image, and the transfer efficiency is increased, so that an image excellent in sharpness and high resolution can be reproduced. The average particle size of the toner used is about 4 to 8 μm.
However, since the shape is spherical or nearly spherical, there is a disadvantage that the cleaning performance is inferior to that of pulverized toner.
For this reason, when spherical toner is used, cleaning performance becomes important.
The toner and the carrier are mixed so that the toner concentration is 3 to 8% by weight.

  The developed and visualized toner image is transferred (transferred) from the paper feed tray 10 by a transfer device 5 (in FIG. 15, a roller-like transfer device can also be used) (copying device). Paper) 11, separated from the photosensitive member 1 by the separation device 6, transported to the fixing device 9, made into a hard copy 13, and stocked on the paper discharge tray 12.

After the toner image has been transferred, the photosensitive member 1 is cleaned by a cleaning device 7 provided with a cleaning blade 71, the residual charge of the photosensitive member is discharged by a charge removing device 8, and the copying process ends.
In FIG. 15, the cleaning device 7 is of a type in which only the cleaning blade 71 is disposed, but a cleaning device with a cleaning brush 72 can also be used as shown in FIG.
The cleaning brush 72 plays an auxiliary role of the cleaning blade 71 and is effective when the amount of toner on the photosensitive member 1 is large. This is effective for a high-speed image forming apparatus that discharges about 40 or more toners, and is effective for an apparatus in which the cleaning unit is disposed above the photosensitive member. The cleaning brush 72 is usually a member in which the brush is closely planted on the substrate, but the toner and carrier are clogged between the fibers, causing clogging, and the cleaning performance, the photoconductor is damaged, and the wear is promoted. There is a possibility. Therefore, the brush is not dense over the entire surface of the roller, but as shown in FIG. 17, a row of fibers (cut pile brush) is formed in the longitudinal direction of the photoreceptor, and the interval between the rows of fibers is 2-5 ( mm), it is desirable to open it about, and the above-mentioned problems can be improved. The amount of biting of the brush into the photoreceptor 1 is preferably set to about 0.5 to 1.5 mm.

  The cleaning brush is either a loop brush or a cut pile brush. Although it is desirable to use properly depending on the system conditions, the main purpose of cleaning is the cleaning blade, and the brush serves as an auxiliary role. Therefore, the purpose can usually be achieved with a cut pile brush. When the amount of toner discharged is large, the use of a loop brush may improve the cleaning effect.

  The material of the brush used for the cleaning brush includes nylon fiber, acrylic fiber, polyester fiber, carbon fiber, etc., and fiber manufacturers include Unitika, Toray, Kanebo, Kuraray, Mitsubishi Rayon and the like. For example, when a loop-shaped cleaning brush is used, the fiber diameter of the fiber used for the brush is 10 to 20 (denier = D: denier D = weight of the yarn (g) × 9000 ÷ length of the yarn (m). ), The density is 24 to 48 filaments / 450 loops, and the loop length (fiber length) is 2 to 5 mm.

  Next, the case where the cleaning apparatus equipped with the cleaning blade 71 of the present invention is applied to an image forming apparatus including a plurality of photosensitive members as latent image carriers will be described with reference to FIG. The image forming apparatus in this case uses a tandem system in which a plurality of photoconductors are juxtaposed along the extending direction of the image transfer body.

Conventionally, a full-color image forming apparatus is an image forming apparatus in which four color developing devices composed of M (magenta), C (cyan), Y (yellow), and Bk (black) are arranged on one photoconductor. Although the copy speed was 3 to 6 (ppm), in recent years, four-tandem image formation in which four copying systems shown in FIG. 15 are incorporated in one image forming apparatus as shown in FIG. Many devices (printers and copiers) are used.
The quadruple tandem image forming apparatus shown in FIG. 18 separates a full-color original into light corresponding to G (green), R (red), and B (blue), and M (magenta) and C (cyan). The electrostatic latent image formed on the photosensitive member is developed with four color developers of Y, Y (yellow), and Bk (black), and the toner of four colors is transferred onto the intermediate transfer belt, and then the transfer target (copy) Paper) and heat-fixed to make a hard copy. The copying speed is four times that of a conventional full-color image forming apparatus.

In a full-color image forming apparatus, color reproducibility is particularly important. Accordingly, it is necessary to make it difficult for the toner layer to be deteriorated, the toner reproducibility to be deteriorated, the abrasion to be accelerated by the cleaning blade, and the occurrence of scratches to be prevented so that the color reproducibility is not deteriorated by the color mixing. Therefore, it is necessary to sufficiently prevent the vibration of the blade 71d, the distortion of the blade edge 71f, and the toner and the carrier from getting under the cleaning blade due to the increase in the frictional resistance between the cleaning blade 71 and the photosensitive member. That is, it is necessary for the cleaning blade 71 to smoothly rub against the photoreceptor 1.
Next, an example in which a cleaning device equipped with a cleaning blade of the present invention is mounted on a process cartridge that is detachable from an image forming apparatus will be described with reference to FIG.

(4) Process cartridge The function of the cleaning blade is exactly the same as when mounted in the image forming apparatus shown in FIG.
Examples of process cartridges are shown in FIGS. It is extremely effective to mount the cleaning blade of the present invention on a process cartridge. As the toner cleaning property is enhanced, the durability of the photosensitive member and the charging member is enhanced and the image quality is maintained, so that the reliability of the process cartridge is increased, the replacement frequency is reduced, and the cost is reduced.

FIG. 19 shows a process cartridge including a cleaning device 107 in which a charging member (charging roller) 102, a developing device 104, and a cleaning blade 71 are disposed around a photosensitive member 101.
FIG. 20 shows an example of a process cartridge in which a charging member (charging roller) 2, a cleaning blade 71, and a cleaning brush 72 are mounted and integrated on the photoreceptor 1.
By integrating these members into a process cartridge that can be integrated into the image forming apparatus, if an abnormality related to these members occurs, the process cartridge can be replaced to immediately recover the failure. I can do it. When maintenance is performed, time can be saved, which is advantageous in terms of cost.

Hereinafter, the present invention will be described by way of examples.
In the following description, “part” means “part by weight”.
First, tests and measurement methods related to the present invention will be described.

(1) Blade squeeze evaluation A color copier (image Neo Neo C455 manufactured by Ricoh) was used for blade squeeze evaluation of the image forming apparatus. A small microphone was mounted on the back side of the front panel of the color copying machine at a position closest to the mounting position of the photosensitive unit to be evaluated. This microphone was connected to a personal computer, and the driving sound of the electrophotographic photosensitive member was recorded by acoustic analysis software (E.N. Software FFT Wave Version 7.7). The quality of the noise was judged by comparing the frequency characteristics of the sound obtained by Fourier transforming the obtained acoustic data.
An example of the obtained data is shown in FIGS.
FIG. 25 shows frequency characteristics of operation sound in a blank state in which the photosensitive unit is not set. No peak is seen around 5 kHz.
FIG. 26 shows an electrophotographic photosensitive member that is used together with an electrophotographic photosensitive member having a cross-linked resin surface layer having no convex shape and a cleaning blade provided with a hard coat resin layer. It is the frequency characteristic of the operation sound at the time of driving. In this case, a blade squeal was heard. From the frequency characteristics of the recorded data, a peak of acoustic power is seen at about 5 kHz.
FIG. 27 is a graph showing the frequency characteristics of the operating sound when the electrophotographic photosensitive member having a convex shape on the surface corresponding to the present invention is replaced with FIG. In the frequency characteristics of the recorded data, the sound power peak disappears at about 5 kHz.

(2) Measurement of slip-through strength First, the slip-through strength in the present invention will be described.
The slip-through strength in the present invention represents the amount of toner that passes through the cleaning blade in the process of collecting the toner adhering to the photosensitive member by the cleaning blade. The slipped toner is collected by placing a white felt of 1 mm thickness and 8 mm × 310 mm on a white background (manufactured by Ashiya Co., Ltd., hereinafter referred to as “slip toner catcher”) downstream of the cleaning blade and upstream of the developing device opening and contacting the photoreceptor. did.
The felt contamination was converted to digital data with an image scanner, and the shade (image density) was classified into five levels. The area (image area ratio) of each density divided into five levels was determined, and the slip-through strength was calculated from the following formula (Formula 1).
(Slip-through strength; T) = Σ (image area ratio) × (image density) (Formula 1)

  Here, the image density is, of course, substantially proportional to the amount of toner present per minute unit area, so that each area ratio is reflected for each specific image density (five steps), and the obtained five results are added. In this case, a value almost corresponding to the total amount of toner that has passed through can be obtained. It is possible to collect the slipped toner and measure its weight. However, the degree of image smearing is stronger than the weight of the slipped toner to the optical density caused by the slipped toner. Involved. The above “substantially proportional” and “substantially match” mean this. It seems that the total weight of the slipped toner is not a reflection of the particle size distribution state of the toner particles constituting the toner. The image area ratio and image density were measured by Media Cybernetics Image-Pro Plus Ver. This was done using a 3.0 PSEUDO-COLOR command. The slip-through strength has a minimum value of 0 and a maximum value of 500.

In the test, a photosensitive member, a cleaning blade, a developing means, and a slipping toner catcher are attached to the image forming apparatus so as to have a layout shown in FIG. 28, and the charging potential, the developing bias, and the amount of light to be written are adjusted. Unify the amount of toner input to. Then, 50 A4 size images having an image density of 5% are continuously printed out. Thereafter, the slipping toner catcher is collected, and the slipping strength is calculated by the above method.
If this slip-through strength is too high, filming on the surface of the photoreceptor is likely to occur. On the other hand, if it is too small, the cleaning blade is pulled in by the rotation of the photosensitive member, and as a result, the blade is turned over or excessive toner slips out. The slip-through strength is desirably 5 or more and 50 or less. Thereby, streaky toner filming can be avoided. Further, when the slip-through strength is set to 5 or more and 30 or less, a high-quality printed image that does not feel a background stain can be obtained.

Actual measurement was performed according to the following procedure. That is, among the photoreceptor sets of imgio Neo C455 manufactured by Ricoh, a photoreceptor set for slip-through strength measurement was obtained by removing the cleaning brush, the charging roller cleaner, and the rod-shaped zinc stearate. The mounting position was the black development station. Among the bias applied to the charging roller of Imagio Neo C455, the DC bias was adjusted so that the charged potential of the photoconductor was -700V. Next, the amount of writing light was adjusted so that the exposure portion potential was −250V. In this state, a solid pattern was written with various development biases. The toner input to the photoreceptor before transfer is collected with a transparent adhesive tape (Nitto Denko Corporation, Printac C), and the image density of the collected tape is measured with a reflection spectrodensitometer (Canon Itec Co., Ltd., X-RITE939). Measured and changed to a developing bias at which this density is 1.0.
Next, a 2 mm thick linear sponge tape (Sumitomo 3M, Scotch tape 4016) is passed through the upper end of the opening of the developing means, and a slipping toner catcher (felt of 8 mm × 310 mm with a thickness of 1 mm (manufactured by Ashiya)) Pasted together. This was attached to the main body.

The cleaning blade is a genuine Imagio Neo C455 genuine article, a cleaned photoconductor drum is attached, and 50 A4 size test pattern images with a 5% image density in a 23 ° C. and 55% RH environment, copy paper (My Paper) A4, manufactured by NBS Ricoh Company). A genuine polymerized toner was used as the toner.
After printing, the slipping toner catcher was collected, and this image was converted into digital data using an image scanner (Epson, ES-8500). The scanner read the image data under the conditions of zoom 100%, color correction by color driver; 1.0, output 800 dpi, photo; 800 dpi, unsharp mask;
For this image data, image analysis software (Media Cybernetics Image Pro Plus Ver3.0) is used, and the Pseudo-Color command is used to determine the image density and area ratio of the slipping toner catcher under the conditions of an upper limit of 210, a lower limit of 310, and a five-division condition. The sum of these was calculated as the slip-through strength.
When recording the drive sound of the electrophotographic photosensitive member, only one photosensitive unit to be evaluated was mounted in the color copying machine, and the developing unit and the transfer unit were excluded.

Example 1
<Electrophotographic photoreceptor>
A cylindrical aluminum support (wall thickness: 0.8 mm, length: 340 mm, outer diameter: 30 mmφ) is dip-coated using the following undercoat layer coating solution, and the film thickness after heat drying is 3. An undercoat layer was formed so as to have a thickness of 5 μm. The film thickness of the undercoat layer was determined by measuring an average of 6 points in the axial direction of the surface with an eddy current film thickness meter. The film thickness of each layer was calculated by subtracting the film thickness before coating from the film thickness after coating.
(Coating liquid for undercoat layer)
Alkyd resin 6 parts (Beckosol 1307-60-EL, manufactured by Dainippon Ink & Chemicals, Inc.)
Melamine resin 4 parts (Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals, Inc.)
Titanium oxide (CR-EL: Ishihara Sangyo) 40 parts Methyl ethyl ketone 50 parts

On this undercoat layer, it was dip-coated in a charge generation layer coating solution containing a bisazo pigment having the following structure and dried by heating to form a charge generation layer having a thickness of 0.2 μm.
(Coating solution for charge generation layer)
2.5 parts of bisazo pigment with the following structure
Polyvinyl butyral (XYHL, manufactured by UCC) 0.5 part Cyclohexanone 200 parts Methyl ethyl ketone 80 parts

On this charge generation layer, the following charge transport layer coating solution was used for dip coating and dried by heating to form a charge transport layer having a thickness of 22 μm.
(Coating liquid for charge transport layer)
Bisphenol A type polycarbonate (Panlite TS2050, manufactured by Teijin Chemicals Ltd.) 10 parts Low molecular charge transport material 10 parts of the following structure
Tetrahydrofuran 80 parts 1% Silicone oil tetrahydrofuran solution 0.2 parts (KF50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.)

Next, a cross-linked surface layer coating solution having the following composition was filled into a spray gun (manufactured by Olympos) and applied at an atomization pressure of 3.0 kgf / mm ² , a discharge rate of 8 g / min, and a coating time of about 60 seconds. . The rotational speed of the electrophotographic photosensitive drum was about 80 revolutions / minute, and the coating speed was about 3.7 mm / second.
(Crosslinked surface layer coating solution)
38 parts of radically polymerizable compound having the following charge transporting structure (2- [4 ′-(di-p-tolyl-amino) -biphenyl-4-yl acrylate]
-Ethyl
・ 19 parts of trimethylolpropane triacrylate (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.)
・ 19 parts of caprolactone-modified dipentaerythritol hexaacrylate (KAYARAD DPCA-120, manufactured by Nippon Kayaku Co., Ltd.)
-0.1 part of acrylic group-containing polyester-modified polydimethylsiloxane and propoxy-modified-2-neopentylglycol diacrylate mixture (BYK-UV3570, manufactured by Big Chemie)
1-hydroxycyclohexyl phenyl ketone 4 parts (Irgacure 184, manufactured by Ciba Specialty Chemicals)

Next, spray coating was further performed on the obtained electrophotographic photosensitive member using the above-described crosslinkable surface layer coating solution. The spray gun was the same, the atomization pressure was 3 kgf / mm ² , the discharge rate was 4 g / min, the electrophotographic photosensitive drum rotation speed was about 100 rotations / minute, and the oscillating speed was about 15 mm / second. UV cured and heat dried. As a result, the convex part containing the crosslinked resin which does not contain a filler was formed. FIG. 29 and FIG. 30 show the surface shape measurement result and laser microscope image by the roughness meter. Similar to Example 1, a plurality of convex portions were independently formed.
The convex part of Example 1 was similar to the shape formed when a downward parabola was rotated about the axis. Rz was 1.873 μm.
Measurement conditions are: calculation standard: JIS 2001, measurement length: 12 mm, cut-off wavelength: 0.8 mm, measurement magnification × 20 K, measurement speed 0.06 mm, cut-off: R2C (phase compensation), slope correction least square method did. In this case, the number of convex portions of 1/2 Rz μm or more obtained from the roughness curve was 42.

<Cleaning blade>
For the cleaning blade that can be mounted on the color copying machine Imagio Neo C455 manufactured by Ricoh Co., Ltd., a hard coat resin layer was provided to a distance of 5 mm from the ridge line of the cut surface front surface and the other air surface via the ridge line in the blade edge portion.
The rubber plate used for the cleaning blade was a polyurethane rubber having a hardness (JISK6301 JIS-A) of 72 degrees and a rebound resilience (JISK6301 Lupke type) of 30.
The contact angle between the cleaning blade and the photosensitive member was 15.5 °.
Film formation of the hard coat resin layer was obtained by covering portions unnecessary for film formation with a masking tape and spray coating the paint. That is, a cross-linked surface layer coating solution having the following composition is filled in a spray gun (manufactured by Olympos), and applied at a pressure of 2.5 kgf / mm ² , a discharge amount of 8 g (5 cc) / min, and a coating time of about 60 seconds. did. The rotational speed of the electrophotographic photosensitive drum was about 40 revolutions / minute, and the coating speed was about 2.7 mm / second.

(Hard coat resin layer coating solution)
・ 19 parts of trimethylolpropane triacrylate (KAYARAD TMPTA, manufactured by Nippon Kayaku Co., Ltd.)
-19 parts of caprolactone-modified dipentaerythritol hexaacrylate (KAYARAD DPCA-120, manufactured by Nippon Kayaku Co., Ltd.)
-0.1 part of acrylic group-containing polyester-modified polydimethylsiloxane and propoxy-modified-2-neopentylglycol diacrylate mixture (BYK-UV3570, manufactured by BYK Chemie)
1-hydroxycyclohexyl phenyl ketone 4 parts (Irgacure 184, manufactured by Ciba Specialty Chemicals)
After film formation, it was dried by heating at 80 ° C. for 60 minutes.

(Example 2)
<Electrophotographic photoreceptor>
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the conditions of the second spray coating of the cross-linked resin film surface layer coating solution in Example 1 were changed as follows.
Discharge amount: 2g
Atomization pressure: 1 kgf / cm ²
Drum rotation speed: 100rpm
Coating speed: 20mm / s
<Cleaning blade>
In exactly the same manner as in Example 1, a cleaning blade having a hard coat resin layer on the edge portion was obtained.

(Example 3)
<Electrophotographic photoreceptor>
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the conditions of the second spray coating of the cross-linked resin film surface layer coating solution in Example 1 were changed as follows.
Discharge amount; 5g
Atomization pressure: 3 kgf / cm ²
Drum rotation speed: 200rpm
Coating speed: 10mm / s
<Cleaning blade>
In exactly the same manner as in Example 1, a cleaning blade having a hard coat resin layer on the edge portion was obtained.

Example 4
<Electrophotographic photoreceptor>
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the conditions of the second spray coating of the cross-linked resin film surface layer coating solution in Example 1 were changed as follows.
Discharge amount: 8g
Atomization pressure: 3 kgf / cm ²
Drum rotation speed: 300rpm
Coating speed: 20mm / s
<Cleaning blade>
In exactly the same manner as in Example 1, a cleaning blade having a hard coat resin layer on the edge portion was obtained.

(Comparative Example 1)
<Electrophotographic photoreceptor>
In Example 1, an electrophotographic photosensitive member having a 4 μm thick cross-linked surface layer was obtained in the same manner as in Example 1 except that the coating of the cross-linked resin film surface layer was performed only once. The result is shown in FIG. The surface of the comparative example 1 was flat compared with the example 1, and the convex part was not recognized.
<Cleaning blade>
In exactly the same manner as in Example 1, a cleaning blade having a hard coat resin layer on the edge portion was obtained.

(Comparative Example 2)
<Electrophotographic photoreceptor>
A convex electrophotographic photosensitive member was obtained in exactly the same manner as in Example 1.
<Cleaning blade>
A cleaning blade which is a genuine product of Ricoh color copier Imagio Neo C455 was used. This cleaning blade is a polyurethane rubber blade, and no hard coat resin layer is provided on the edge portion thereof.

(Comparative Example 3)
<Electrophotographic photoreceptor>
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the cross-linked resin film surface layer was omitted in Example 1.
<Cleaning blade>
In exactly the same manner as in Example 1, a cleaning blade having a hard coat resin layer on the edge portion was obtained.

(Comparative Example 4)
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the conditions of the second spray coating of the cross-linked resin film surface layer coating solution in Example 1 were changed as follows.
Discharge amount: 1g
Atomization pressure: 1 kgf / cm ²
Drum rotation speed: 100rpm
Coating speed: 10mm / s
<Cleaning blade>
In exactly the same manner as in Example 1, a cleaning blade having a hard coat resin layer on the edge portion was obtained.

(Comparative Example 5)
An electrophotographic photosensitive member was obtained in the same manner as in Example 1 except that the conditions of the second spray coating of the cross-linked resin film surface layer coating solution in Example 1 were changed as follows.
Discharge amount; 5g
Atomization pressure: 5 kgf / cm ²
Drum rotation speed: 400rpm
Coating speed: 20mm / s
<Cleaning blade>
In exactly the same manner as in Example 1, a cleaning blade having a hard coat resin layer on the edge portion was obtained.

After the electrophotographic photoreceptors of Examples 1 to 4 and Comparative Examples 1 to 5 and the cleaning blade produced as described above were mounted, they were mounted on a cyan developing station of an electrophotographic apparatus (image Neo Neo C455, manufactured by Ricoh). Then, simultaneously with closing the front panel of the main body, the photosensitive drum was driven for 14 hours. After driving for 14 hours, the driving sound of the electrophotographic photosensitive member was recorded using a microphone, and the frequency characteristics of the recorded data were compared. The transfer belt of the electrophotographic apparatus, the development units for all colors, and the photosensitive units of the black, yellow and magenta development stations were excluded.
The results are shown in Table 1.

In Comparative Example 1, the surface of the electrophotographic photosensitive member was not given a convex shape, and an unpleasant blade squeal occurred when combined with a cleaning blade provided with a hard coat resin layer on the blade edge. On the other hand, it can be seen that blade squeal is suppressed in Examples 1 to 4 having a convex shape. It is considered that the convex shape of the photoconductor is important for blade noise. For now, the cause of this is unknown, but we are thinking as follows. For example, in the case of Example 1, there were 57 convex portions satisfying a height of 1/2 Rz or more in a measurement length of 12 mm. This shape is a wart shape. In this experiment, the linear velocity of the photoconductor was 125 mm / s. Under this linear velocity condition, 594 convex portions pass per second. It is considered that a new low-frequency vibration has occurred according to the shape of the electrophotographic photosensitive member. We believe that this new vibration has changed the vibration caused by blade noise. In some cases, noise reduction may not be obtained even if a concave shape such as Comparative Example 4 or Comparative Example 5 is provided on the surface of the photoreceptor, and an appropriate range for the number of convex shapes satisfying a height of 1/22 Rz or more. There is.
Further, in Comparative Example 2, the result that the toner slips through is obtained. The cleaning blade at the end of the test was significantly worn compared to the other examples, which is considered to be the cause. Comparative Example 3 also obtained a result with much toner slipping. Foreign matter was filmed on the surface of the photoreceptor. It is considered that toner slip-through increased due to the influence of the surface.

According to the present invention, it is possible to provide an image forming apparatus in which an electrophotographic photosensitive member having a highly durable and suitable rough surface and a cleaning blade having excellent wear resistance can be used in combination. Since the electrophotographic photosensitive member mounted in the present invention has a controlled convex portion formed on the surface, it is possible to prevent the rubbing noise between the electrophotographic photosensitive member and the cleaning blade.
The present invention eliminates blade noise that impedes practical use in combination with a cleaning blade having a hard coat resin layer at an edge portion advantageous for cleaning performance and an electrophotographic photoreceptor having a cross-linked resin film having extremely excellent durability on the surface layer. An electrophotographic apparatus having a high practical value is provided.

It is a conceptual diagram of the electrophotographic photosensitive member which has a convex part on the surface of a surface layer. Convex part with indefinite shape (plan view, random arrangement) It is a conceptual diagram at the time of making the vertical and horizontal magnification of a convex part close. It is a conceptual diagram which shows a circular convex part (a top view, regular arrangement | positioning). It is a conceptual diagram which shows a square convex part (a top view, regular arrangement | positioning, and a corner is round). It is a conceptual diagram which shows an elliptical convex part (a top view, regular arrangement | positioning). It is a conceptual diagram which shows an elliptical convex part (a top view, random arrangement | positioning). It is a conceptual diagram which shows a hexagonal convex part (a top view, regular arrangement | positioning). It is a figure which shows the outline | summary of the formation apparatus of the convex part by a spray method. It is a figure which shows the outline | summary of the formation apparatus of the convex part by the inkjet method. It is the schematic which shows an example of the laminated constitution of the electrophotographic photoreceptor in this invention. It is the schematic which shows the other example of the layer structure of the electrophotographic photoreceptor in this invention. It is the schematic which shows the other example of the layer structure of the electrophotographic photoreceptor in this invention. It is a figure which shows an example of the cleaning blade by this invention. It is a figure which shows another example of the cleaning blade by this invention. It is a figure which shows an example of the principal part structure of the cleaning blade by this invention. It is a figure which shows the other example of the principal part structure of the cleaning blade by this invention. It is a figure for demonstrating the contact angle of the cleaning blade by this invention. It is a figure which shows an example of the image forming apparatus equipped with the cleaning apparatus in which the cleaning blade of this invention is used. It is a figure which shows the other structure of the cleaning apparatus shown in FIG. It is a figure which shows the structure of the cleaning brush used for the cleaning apparatus shown in FIG. FIG. 16 is a diagram illustrating another example of the image forming apparatus illustrated in FIG. 15. It is a figure which shows the structure of the process cartridge used for the image forming apparatus shown in FIG. FIG. 20 is a diagram showing another example of the process cartridge shown in FIG. 19. It is a figure which shows the prior art example of the installation condition of a cleaning blade. It is a figure for demonstrating the malfunction in the cleaning blade shown in FIG. 2 shows the behavior of a finely pulverized residual toner corresponding to foreign matter. FIG. 24 is a diagram for explaining a problem during cleaning of the residual toner illustrated in FIG. 23. 6 is a graph showing frequency characteristics of operation sound in a state where the photosensitive unit of the image forming apparatus used in the example is not set. The image forming apparatus used in the example is equipped with an electrophotographic photosensitive member in which an electrophotographic photosensitive member for laminating a crosslinkable resin surface layer having no convex shape and a cleaning blade provided with a hard coat resin layer is mounted. It is a graph showing the frequency characteristic of the operation sound at the time of driving a body. FIG. 27 is a graph showing frequency characteristics of operation sound when the electrophotographic photosensitive member having a convex shape on the surface corresponding to the present invention is replaced with FIG. It is an example showing the layout around the photoconductor for measuring the slip-through strength. 3 is a measurement result of a surface shape by a roughness meter of the electrophotographic photosensitive member obtained in Example 1. FIG. 2 is a laser microscope image of the electrophotographic photosensitive member obtained in Example 1. FIG. 2 is a laser microscope image of the electrophotographic photosensitive member obtained in Comparative Example 1.

Explanation of symbols

(Figs. 7-9)
31 Conductive support
33 Photosensitive layer
35 Charge generation layer
37 Charge transport layer
39 Surface layer
(FIGS. 10-20)
DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charging apparatus 3 Image exposure apparatus 4 Developing apparatus 5 Transfer apparatus 6 Separation apparatus 7 Cleaning apparatus 8 Static elimination apparatus 9 Fixing apparatus 10 Paper feed tray 11 Transfer object 12 Paper discharge tray 13 Hard copy 71 Cleaning blade 71a Support 71b Mounting hole 71c Positioning hole 71d Blade 71e Hard coat resin layer 72 Cleaning brush 101 Photoconductor 102 Charging device
103 exposure
104 Developing device
105 Transcript
106 Transfer device
107 Cleaning blade
25-28
A Electrophotographic photosensitive member B Doctor blade B1 Doctor blade tip edge surface C Wedge space T Toner

Claims (8)

An electrophotographic photosensitive member having at least a photosensitive layer and a surface layer on a conductive support, and an image forming apparatus on which a cleaning blade for cleaning foreign matter such as residual powder is mounted. The photosensitive member has a convex portion formed on the surface layer, the surface layer and the convex portion contain a cross-linked product of the same charge transporting compound, and the surface roughness of the surface layer is expressed in RzJIS. In this case, the number of convex portions having a height of ½ × RzJIS or more is 20 to 80 per 12 mm measurement length, and the cleaning blade is hard on the contact portion with the electrophotographic photosensitive member. An image forming apparatus comprising a coat resin layer.
(However, RzJIS means the ten-point average roughness of the 2001 JIS standard (JIS B0601: '01). The height of the convex portion is the distance from the waviness curve of the surface layer to the top of the convex portion, and (An average value obtained by measuring at least four locations at arbitrary positions in the formation region.)   The image forming apparatus according to claim 1, wherein an average value of RzJIS of the electrophotographic photosensitive member is 0.05 μm or more and 6 μm or less. The image forming apparatus according to claim 1, wherein the cross-linked product of the charge transporting compound has a triarylamine structure. The image forming apparatus according to claim 1, wherein the charge transporting compound is a compound represented by the following general formula 1.
(Wherein, d, e and f are each an integer of 0 or 1, R ₁₃ represents a hydrogen atom or a methyl group, R ₁₄ and R ₁₅ represent a substituent other than a hydrogen atom and an alkyl group having 1 to 6 carbon atoms. And may be different from each other, g and h each represent an integer of 0 to 3. Z is a single bond, a methylene group, an ethylene group,
Or
Represents. )   The image forming apparatus according to any one of claims 1 to 4, wherein a method for forming the convex portions of the electrophotographic photosensitive member is a spray coating method.   The image forming apparatus according to claim 1, wherein development is performed using at least a polymerized toner.   The image forming apparatus according to claim 6, wherein the image forming apparatus has at least two or more development stations and is a tandem system. 8. The image forming apparatus according to claim 1, wherein the image forming apparatus includes a process cartridge that is detachable from an image forming apparatus main body including at least an electrophotographic photosensitive member, a developing unit, and a cleaning unit. .