JP2005345493A - Cleaning blade, cleaning device, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning blade which, first ensures satisfactory cleaning without adverse effects of spherical toner on image quality, and maintains the performance, secondly retains the durability of a blade edge, and thirdly restricts abrasion, such as scratch, on a photoreceptor, and thus ensures steady image formation over a long period. <P>SOLUTION: The cleaning blade 71 for clearing away foreign matter, such as residual powder, includes a blade main body 71d supported in a cantilever manner relative to a surface 1 on which foreign matter remains, such that its basal end is immovable and the edge 71f of its free end can be brought into pressurized contact with the surface 1; and a lubricant layer 71e, formed on the surface of the blade body 71d and also at least on the face that is opposite the surface 1 on which foreign matter remains. The blade body 71d is set so as to be brought into a pressurized contact state, in which the edge 71f and the lubricant layer 71e are simultaneously brought into contact with the surface 1 on which foreign matter remains. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cleaning blade, a cleaning device, and an image forming apparatus, and more particularly to a configuration for scraping and removing foreign matters including powder such as toner remaining on a latent image carrier such as a photoreceptor.

  In an image forming apparatus using an electrophotographic method, charging, image exposure, development, transfer, separation, cleaning (cleaning), and static elimination are arranged around an electrophotographic photosensitive member.

In image formation, first, a charge is uniformly applied (charged) to the surface of an electrophotographic photoreceptor (hereinafter simply referred to as a photoreceptor) through a charging member to which a high voltage is applied.
Next, information (signals) such as a manuscript to be copied or a personal computer (personal computer) is converted into an optical signal of a dot pattern using an LD element or LED element array as a light source, and is exposed through a polygon mirror, a cylindrical lens, or the like. Irradiate the body surface to form an electrostatic latent image (contrast image). The electrostatic latent image is developed with a two-component developer in which a toner having an average particle diameter of about 4 to 8 (μm) and a magnetic powder called carrier having an average particle diameter of about 40 to 60 (μm) are mixed. The toner image is visualized.

  The toner includes a pulverized toner that is irregularly shaped and irregularly manufactured by a pulverization method, and a spherical or nearly spherical polymerized toner that is chemically manufactured. Each of these types of toner has advantages and disadvantages, but with the demand for higher image quality, the particle size is almost uniform and the particle size distribution is narrow, the transfer efficiency is good, and the manufacturing cost is lower than the pulverized toner. Polymerized toners having many advantages (also called spherical toners because they are spherical with no sharp points) have been used.

  The toner image is transferred to a transfer medium (copy paper) by a transfer means such as a roller or a belt to which a voltage having a polarity opposite to that of the toner is applied, and then fixed by means such as heat or pressure to form a hard copy. .

  On the other hand, since the untransferred toner remains on the photoconductor after transfer, the surface of the photoconductor is cleaned by a cleaning member (hereinafter referred to as a cleaning member) in order to prepare for the next image formation.

  By the way, as a cleaning member, a brush cleaning method using a fiber brush, a blade cleaning method using a rubber blade, and a cleaning method using both of them are known, but a compact design can be achieved and durability is relatively good. Therefore, the blade cleaning method is frequently used because of its high cleaning efficiency.

  As the blade used for blade cleaning, a rubber-like elastic body having good adhesion without causing mechanical damage to the photoreceptor is used. Rubber materials that can be used as blades include silicone rubber, fluoro rubber, chloroprene rubber rubber, urethane rubber, etc., but exhibit excellent properties such as mechanical durability, chemical stability (for example, ozone resistance) and cleaning properties. Polyurethane rubber is used favorably as a cleaning blade.

  The cleaning blade is obtained by fixing a rubber plate (blade) formed into a plate shape to a support such as an aluminum plate or an iron plate. A constant load (pressing) is applied, and the edge of the blade comes into contact with the photosensitive member. Installed. As means for contacting the photosensitive member, the blade edge makes contact with the photosensitive member in the counter direction (the direction in which the blade edge bites when the photosensitive member rotates), or the trailing direction (the photosensitive member). There is a method of contacting the blade edge so that the blade edge licks (no biting) = forward direction) during rotation, but the method of contacting in the counter direction is excellent in cleaning properties, so it is generally installed at the counter contact. ing. That is, the counter abutment causes the edge of the cleaning blade to bite by the rotation of the photoconductor, so that the gap between the photoconductor and the blade edge is eliminated and the cleaning performance is improved.

On the other hand, as described above, as for the cleaning blade, a counter system in which the tip is positioned and brought into contact with the moving direction of the latent image carrier so as to be in contact is well known. When the coefficient of friction of the body surface is increased, the frictional force on the blade tip is increased, and as a result, the blade tip is turned and warped by being easily dragged by the latent image carrier. Hereinafter, this point will be described.
FIG. 19 shows a case where the above-described counter type cleaning blade is used. As the doctor blade B, an elastic material that can easily obtain bending rigidity is used. For example, when the drum A is used as a latent image carrier, The latent image carrier A is set by contacting it with an angle θ so as to be a counter with respect to the rotation direction R of the latent image carrier A, and further pushing the leading end against the bite (the bite amount indicated by d in the figure). Cleaning is performed by scraping off toner remaining on the body surface.
However, when the friction coefficient on 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.

  When the contact charging method described above is used, as shown by a two-dot chain line in FIG. 20, the discharge product D generated when using contact charging adheres to the surface of the latent image carrier A, As a result, the degree to which the tip of the blade B is turned up is increased by the thickness of the discharge product, and the wedge-shaped space C is enlarged because the tip of the blade B1 is easily dragged together with the increase in frictional force. It exhibits such a wedge shape. When the tip of the blade is turned up, a frictional resistance is generated between the blade and the latent image carrier, and not only the surface of the latent image carrier is easily damaged, but also the rotational resistance of the latent image carrier is increased. In other words, there is a concern that the operation lock of the latent image carrier may occur, and in this case, there is a possibility that the peripheral parts including the latent image carrier are replaced.

On the other hand, the turning-up phenomenon that occurs when the blade tip is rubbed against the latent image carrier also adversely affects the scraping of residual toner.
In recent years, high image quality has been required for electrophotographic systems as the quality of ink jet printers has been improved. The finest image quality can be obtained by making the toner, which is a material to be visualized as a factor contributing most to high image quality, into a spherical shape with a small particle diameter. For this reason, as a technique for reducing the particle size, a conventional toner production method has been carried out by using a toner having a desired particle size region by crushing a lump of toner into fine particles and classifying them.
However, the toner deviating from the distribution range in this method has been discarded or re-melted and reused. In this way, productivity was poor and it was against the recent energy saving. Therefore, instead of the conventional pulverization method, a method for producing a polymerized toner by a polymerization reaction which is a chemical reaction has begun to be performed. There are suspension polymerization, emulsion polymerization, dispersion polymerization and the like as this polymerization toner production method, but any of them does not require a pulverization classification step, and a toner having a desired particle diameter can be obtained in a high yield. In addition, since the polymerization method toner can obtain a high transfer rate, the amount of waste toner is small, so that the energy saving effect is also great in this respect. However, the small particle size and spherical toner using the polymerization method has many advantages, but has a big problem that it is difficult to clean in the process of the image forming apparatus.

  Conventionally, cleaning with an apparatus employing polymerized toner has been performed by cleaning the remaining toner after transfer by deforming the toner shape and cleaning with a blade, or brush cleaning that electrostatically attracts. In this method, an additional process such as a deforming process is required in a process that can be manufactured into an original spherical shape. Further, brush cleaning that is electrostatically attracted increases costs in terms of brush rollers, driving devices, and the like. Also, removing toner from the brush roller has a problem in terms of reliability, and a sufficient effect is not obtained.

In cleaning when pulverized toner is used as the toner having a reduced particle size, the blade tip B1 is dragged to the latent image carrier A to form a wedge shape as shown in FIGS. When the pulverized toner (referred to as T1 for the sake of convenience) is accumulated, the original shape (indicated by the solid line in FIG. 22) is obtained by the elastic restoring force accompanying the stress generated when the blade tip B1 is dragged and deformed by the latent image carrier A. The movement returns to the shape shown in FIG. 22 (the movement in the direction indicated by the symbol SS in FIG. 22).
This phenomenon is stick-slip motion. By this movement, the toner is blown off by the energy when the original shape is restored, and the toner is scraped off from the surface of the latent image carrier.

  On the other hand, when spherical toner having a reduced particle size is used, the phenomenon shown in FIGS. 23 and 24 occurs. That is, in the case of the pulverized toner, the toner itself has a distorted edge, and the edge can be caught on the blade surface. However, the spherical toner (indicated by the symbol T ′ for convenience) has such an edge. Absent. For this reason, it does not get caught in the blade tip and easily enters the wedge-shaped portion. The spherical toner T ′ that has entered the wedge-shaped portion receives a rotational moment from the contact position as a driving source by the frictional force generated between the moving direction of the latent image carrier A and the blade tip B1. Therefore, when this rotational moment is generated, the spherical toner moves through between the wedge-shaped portion of the blade tip B1 and the surface of the latent image carrier, thereby causing a toner scraping failure. Become. In addition, the spherical toner T ′ that tries to pass through functions as a lubricant that reduces the frictional force between the blade tip B1 and the latent image carrier A, and therefore it is difficult for the blade tip B1 to be turned over. As a result, the blade returns to its original shape, that is, it is difficult to obtain an elastic restoring force for causing the stick-slip phenomenon, and the toner scraping action by the elastic restoring force may not function effectively. is there.

Conventionally, the following configuration has been proposed for the purpose of solving such problems.
First, a fluororesin containing 1 to 25% by weight of carbon fluoride on the surface of an elastic thin plate in order to maintain a stable state for a long period of time and a stable cleaning at all times. A technique in which a fluororesin forms a tetrafluoroethylene-perfluoroalkoxyethylene copolymer (for example, Patent Document 1).
Second, in order to prevent image defects such as white streaks, characters or the like caused by adhesion of the siloxane oligomer deposited on the surface of the silicone developing roller to the photoreceptor when using a silicone developing roller, A technique of coating the tip with a 4-6 fluororesin having a solid content of 20 to 30% by weight with an aqueous dispersion (for example, Patent Document 2).
Thirdly, in order to prevent the edge of the cleaning blade from turning over, a technique of forming a coating layer made of a fluorine-based polymer by using a spray method on a portion in contact with the toner adhering body (for example, Patent Document 3) .
Fourth, a technique for forming a fluorine-containing polymer film on the edge portion of the blade and two surfaces extending across the edge portion in order to prevent the cleaning blade from being inverted (for example, Patent Document 4).
Fifth, a technique of applying fine particles of 10 μm or less by means such as a dipping method and removing the solvent and drying in order to realize low friction of the blade edge and prevent blade turning (for example, Patent Document 5).

Sixth, fine particles selected from the group of organic fine particles, inorganic fine particles, and toner having an average particle size of 0.1 μm or more per unit area in order to perform stable cleaning over a long period even with a spherical toner having a small particle size. As a means for adhering 1 to 10 mg / cm ² to the portion in contact with the image carrier and applying the nonionic surfactant, the fine particles are adhered and dried (for example, Patent Document 6).

JP-A-5-46056 (paragraph "0013" column) JP 10-326066 A (paragraph “0013” column) JP 9-258632 A (paragraph “0007” column) JP-A-8-16056 (paragraph "0004" column) JP 2000-147972 (paragraph "0030" column) JP 2003-280474 A (paragraph “0036” column)

The technique disclosed in the above patent document has the following problems.
Since the technique disclosed in Patent Document 1 is a cleaning blade in which a fluorine-based resin is coated on an elastic metal such as a phosphor bronze plate, the blade is very hard. For this reason, the cleaning blade is very unlikely to cause distortion or stick-slip phenomenon, but because the blade uses metal, the image carrier is likely to be rubbed, resulting in deterioration of charging characteristics and image quality. Is inevitable and the image carrier must be replaced. In addition, the adhesion to the photosensitive member becomes dilute, and early cleaning failure is inevitable.
In the technique disclosed in Patent Document 2, since the coated fluororesin needs to take in the siloxane oligomer, the fluororesin needs to be peeled off from the blade. That is, there is a problem that the fluororesin coated on the blade has no effect unless it is replenished, and the sustainability is lost after one coating.

  Since the technology disclosed in Patent Document 3 is simply applied to the blade surface by a fluorine-based lubricant composed of a fluorine-based lubricating layer and a fluorine-based polymer and then dried, the adhesiveness to the urethane blade Cannot be obtained sufficiently, it is consumed immediately and is insufficient in terms of maintaining characteristics (durability). If the blade edge is applied, a sufficient edge is not ensured, so that a gap is formed between the image carrier and a cleaning failure is likely to occur from the beginning when a spherical toner is used.

  In the technique disclosed in Patent Document 4, by forming a fluororesin polymer film on the edge portion, the frictional resistance with the image carrier is reduced and the blade can be prevented from being reversed, but it is also applied to the edge portion. In addition, since the edge function is insufficient and the positive contact with the image carrier is lost, a toner with a high degree of circularity such as a spherical toner can easily form a gap, which may cause a cleaning failure. The nature is great. In addition, since the plasma polymerization method is used, the cost is significantly increased.

  In the technique disclosed in Patent Document 5, since the surface thin layer has two layers, when the edge comes into contact with the image carrier, the edge floats, and in particular, when cleaning spherical toner, there is a possibility of poor cleaning. Moreover, even if a solid lubricating layer is applied on the adhesive layer, it is difficult to obtain sufficient adhesion between the two layers, so that long-term characteristics cannot be maintained, and the effect may be diminished early.

  With the technique disclosed in Patent Document 6, fine particles are removed during use and lost only by being attached to the blade surface. Therefore, an effect can be seen during the initial period, but it is not sufficient to lower the coefficient of friction of the image carrier, and the frictional resistance with the image carrier increases relatively quickly during use, and the blade edge is locally affected. As a result, distortion is likely to occur, and cleaning failure is likely to occur, the durability of the effect is lowered, and long-term stability is lacking.

  In view of the problems in the conventional cleaning blade and the image forming apparatus using the same, the object of the present invention is as follows. First, even a spherical toner can be cleaned so as not to adversely affect image quality. A cleaning blade capable of maintaining stable performance, secondly maintaining the durability of the blade edge, and thirdly making the photoconductor less susceptible to scratches such as scratches, and capable of stable image formation over a long period of time, and An object of the present invention is to provide a used cleaning device and image forming apparatus.

  The invention according to claim 1 is a cleaning blade for cleaning foreign matter including residual powder, wherein the cleaning blade is capable of press-contacting an edge portion against a surface on which the foreign matter remains. A main body and a lubricating layer provided on a surface of the blade main body facing at least the surface on which the foreign matter remains, and the blade main body includes the edge portion and the lubricating layer on the surface on which the foreign matter remains. It is characterized in that a pressure contact state is set in which and are simultaneously pressed.

  According to a second aspect of the present invention, in the cleaning blade according to the first aspect, the blade body is a flexible member, and the lubricating layer is provided in a range excluding at least the edge portion of the blade body. Yes.

  According to a third aspect of the present invention, in the cleaning blade according to the first or second aspect, the lubricating layer is provided in a range excluding an edge portion of the blade body and an end surface continuous thereto.

  According to a fourth aspect of the present invention, in the cleaning blade according to one of the first to third aspects, the end surface of the blade body faces the upstream side in the moving direction of the surface on which the foreign matter remains, and at least an edge. The portion is in pressure contact with the surface on which the foreign matter remains.

  According to a fifth aspect of the present invention, in the cleaning blade according to any one of the first to fourth aspects, the lubricating layer has the blade main body according to a contact angle of the blade main body with respect to a surface on which the foreign matter remains. It is characterized in that it is applied from a position where it can come into contact with the edge portion and the surface in the vicinity thereof, and the surface where the foreign matter remains.

  According to a sixth aspect of the present invention, in the cleaning blade according to any one of the first to fifth aspects, the thickness of the lubricating layer depends on a contact angle of the blade body with respect to a surface on which the foreign matter remains. The thickness is set such that the edge portion of the blade body and the lubricating layer can be in contact with each other at the same time.

  A seventh aspect of the present invention is the cleaning blade according to any one of the first to sixth aspects, wherein the blade body is made of a material having a JIS-A hardness of 60 to 80 degrees. It is said.

  According to an eighth aspect of the present invention, in the cleaning blade according to one of the first to seventh aspects, the blade body has a thickness of 1.5 to 3 mm.

According to a ninth aspect of the present invention, in the cleaning blade according to one of the first to eighth aspects, the blade body is pressed against the surface on which the foreign matter remains with a contact pressure of 15 to 35 g / cm. It is characterized by that.
A tenth aspect of the present invention is the cleaning blade according to any one of the first to sixth aspects, wherein the lubricating layer is formed by applying a material having chemical affinity to the blade body. It is characterized by being.

  The eleventh aspect of the present invention is the cleaning blade according to the tenth aspect, wherein a thermosetting paint containing a fluororesin is used for the lubricating layer when the blade body uses urethane rubber. It is said.

  According to a twelfth aspect of the present invention, in the cleaning blade according to the tenth or eleventh aspect, the lubricating layer has a surface roughness of 3 μm or less and a maximum height Rmax of 5 μm or less at a 10-point average roughness (Rz). It is characterized by being.

  A thirteenth aspect of the present invention is the cleaning blade according to any one of the tenth to twelfth aspects, wherein the thickness of the lubricating layer is set to 20 to 100 μm.

  The invention according to claim 14 is characterized in that the cleaning blade according to one of claims 1 to 13 is used in a cleaning device.

  A fifteenth aspect of the invention is characterized in that, in the cleaning device according to the fourteenth aspect, the cleaning blade is provided in a cartridge provided with a recovery mechanism for the foreign matter removed from the surface on which the foreign matter remains.

  A sixteenth aspect of the invention is characterized in that a process cartridge integrally including the cleaning device of the fourteenth or fifteenth aspect and a photoconductor is detachable from the main body of the image forming apparatus.

  The invention described in claim 17 is characterized in that the cleaning device described in claim 14 or 15 is used in an image forming apparatus.

  According to an eighteenth aspect of the present invention, in the image forming apparatus according to the seventeenth aspect, the surface on which the foreign matter remains is a latent image carrier capable of carrying a toner image to be transferred, and the latent image carrier is a toner. It is characterized in that foreign matter recovery is performed by the cleaning device after image transfer.

  According to a nineteenth aspect of the present invention, in the image forming apparatus according to the eighteenth aspect, the latent image carrier is provided in a single or a plurality, and is selected and installed according to an image forming mode. It is said.

  According to a twentieth aspect of the present invention, in the image forming apparatus according to the eighteenth or nineteenth aspect, when a plurality of latent image carriers are provided, images formed by the latent image carriers are sequentially transferred to an intermediate transfer member or a recording medium. It is characterized in that a structure capable of being superimposed and transferred onto a medium is used.

  According to the first, second, fifth, sixth, and ninth aspects of the present invention, in the blade body whose free end can be pressed against the surface on which the foreign matter remains, the lubricating layer provided in a range excluding the blade body and the edge portion. Since the pressure contact force at the edge portion is increased to improve the scraping property of foreign matters, the increase in the frictional resistance due to the increase of the pressure contact force is alleviated by the contact of the lubricating layer. Can do. As a result, it becomes possible to improve the scraping efficiency by enhancing the damming action against foreign matters such as spherical toner that try to pass through the edge portion, and to suppress the increase in mechanical load due to increased frictional resistance. It is also possible to prevent the generation of abnormal noise due to the increase of the noise.

  According to the third and fourth aspects of the present invention, the lubricating layer has an edge portion of the blade body and an end surface continuous with the edge portion. Thus, the edge portion can be bitten to scrape off the foreign material, and the foreign material can be reliably removed by damming at the end surface continuous with the end surface.

  According to the seventh aspect of the invention, since the blade body is set to 60 to 80 degrees in JIS-A hardness, the foreign matter cannot enter between the edge portion of the blade and the surface on which the foreign matter remains. Therefore, the foreign substance scraping action can be efficiently performed.

  According to the invention described in claim 8, since the thickness of the blade body is set to 1.5 to 3 mm, it is possible to prevent a situation where the edge portion is lifted by ensuring the bending composition, and to ensure that the foreign object is slipped through. Can be prevented.

  According to the inventions of claims 10 and 11, since the lubricating layer is formed by applying a material having chemical affinity with the blade body, the adhesion to the blade body is different from pasting or joining. Can be ensured, and the sliding resistance of the blade body can be reliably reduced.

  According to the twelfth aspect of the invention, since the surface roughness of the lubricating layer is set to 3 μm or less and the maximum height Rmax is set to 5 μm or less at the 10-point average roughness (Rz), the thin film of the lubricating paint is photosensitive. When the body is rubbed, it comes into contact with the surface of the photoconductor so as not to be substantially non-uniform so that the coefficient of friction on the surface of the photoconductor is satisfactorily reduced. Accordingly, the frictional resistance between the surface on which the stamp remains and the cleaning blade is reduced, so that distortion and stick-slip phenomenon hardly occur at the blade edge, and the cleaning performance can be improved.

  According to the invention of claim 13, by setting the thickness of the thin film of the lubricating paint applied to the side surface excluding the edge of the cleaning blade to 20 μm to 100 μm, the function of the blade edge by thin film application is not hindered, The friction coefficient on the surface where the blade body comes into contact can be reduced, which makes it possible to maintain good cleaning over a long period of time even if there are spherical foreign objects that are easy to slip through the blade edge. It becomes.

  According to the fourteenth, fifteenth and sixteenth aspects, both the scraping efficiency by the cleaning blade and the reduction of the frictional resistance can be achieved at the same time.

  According to the seventeenth and eighteenth aspects of the present invention, even when a latent image carrier is used as a surface on which foreign matter remains, it occurs when the scraping efficiency for the toner remaining on the carrier surface is improved and the scraping efficiency is improved. Thus, it is possible to reduce the frictional resistance and suppress an increase in load on the latent image carrier. As a result, it is possible to prevent the mechanical parts from being damaged and to extend the service life of the parts.

  According to the inventions of claims 19 and 20, the latent image carrier is selected in accordance with the image forming mode. In particular, in the invention of claim 20, a plurality of color images are provided by providing a plurality of latent image carriers. When forming the image, it is possible to improve the cleaning property and reliably prevent the generation of a defective image such as a mixed color.

The present invention is implemented by the configuration of a cleaning blade and an image forming apparatus using the same, which will be described below for each item.
(1) 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. It is located between the corresponding transfer device and the static eliminator after image 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 And jig for removing residual powder such as paper powder 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 a cleaning blade,
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 the stick-slip phenomenon occurs.
3) The frictional resistance reducing means is stably maintained over a long period of time.
is important.

An example of the configuration of the cleaning blade is shown in FIGS.
The cleaning blade 71 of the present invention is such that a blade 71d is fixed to a support 71a supported in a cantilever shape, and a thermosetting lubricating paint 71e containing a fluororesin is disposed on the side surface of the blade 71d. In the region excluding the edge 71f, it is applied over the longitudinal direction of the blade 71d as a lubricating layer on at least the surface facing the drum-shaped photoreceptor, which is a latent image carrier denoted by reference numeral 1 in FIG. ing.

  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.

  As shown in FIG. 1A, the shape of the support 71a is a U-shaped holder (either an integral configuration or a combination of two types of members), or as shown in FIG. A letter shape, or a plate shape that is simply cut into a rectangle, although not shown, is used. The support is provided with mounting holes 71b and positioning holes 71c. The support cartridge is screwed to the mounting position of the process cartridge unit or the cleaning device unit and is supported in a cantilever shape, and the blade 71d is positioned at the free end. Yes.

  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.

When a lubricating paint is applied to form the lubricating layer and used in the cleaning blade 71, the desired thickness of the lubricating paint 71e is 1.5 to 3 mm.
If the thickness is smaller than 1.5 mm, the mechanical durability is increased. If the thickness is larger than 3 mm, the area on which the toner is pressed against the photosensitive member 1 becomes larger when the blade is loaded. The blade is likely to float and may cause poor cleaning.

  On the other hand, in order to perform cleaning satisfactorily, it is desirable that the edge 71f of the cleaning blade 71 is in line contact as much as possible. However, if a defect occurs in the blade edge, the risk of defective cleaning increases. When a load (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 shows good cleaning performance in the initial stage. However, when the blade edge is lost, the toner cleaning margin is low and toner omission (defect) is likely to occur. .

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, the frictional resistance is extremely large.
For this reason, if it is used as it is, various problems such as drum noise, stick slip, cleaning failure due to distortion of the blade tip, generation of rubbing noise (abnormal noise) such as a key, and photoconductor lock will occur. Therefore, in order to maintain good image formation and avoid discomfort due to rubbing noise, locking, etc., measures are taken to reduce the coefficient of friction on either the photoreceptor 1 or the blade 71d or both. Necessary. That is, it is necessary to reduce the frictional resistance between the photoreceptor 1 and the cleaning blade 71.

  As a means for reducing the frictional resistance between the cleaning blade 71 and the photosensitive member 1, a method of applying toner or fluorine resin to the blade edge 71f is known. In this method, toner or fluorine resin is sandwiched between the cleaning blade 71 and the photosensitive member to reduce (relax) the frictional resistance of the tip including the edge 71f of the blade 71d. In the case of fluororesin, if it is not replenished constantly, it will be licked by the photoreceptor and will be depleted and lost due to development and cleaning, and the effect will be reduced quickly.

On the other hand, in the case of toner, there is no need to worry about depletion because it is constantly replenished by development, but when applied to the tip of the blade, the toner is sandwiched between the cleaning blade and the photosensitive member, creating a slight gap and 1 μm This causes the front and rear toners to sink, and also causes the filming of the photosensitive member because the toner is constantly pressed down. The slight gap affects the penetration of the spherical toner and has a risk of causing a cleaning failure. Therefore, the initial toner application to the cleaning blade is not a very preferable method except when a toner having a large particle diameter (for example, a particle diameter of 8 μm or 10 μm) is used.
In the case of a fluororesin, the particle diameter is much smaller than that of the toner, and it adheres to the photosensitive member and becomes an extremely thin film of about several tens of liters.

  As means for reducing the frictional resistance between the cleaning blade and the photosensitive member, in the present invention, a lubricant 71d having lubricity and durability is applied to the side surface of the blade 71d, and the lubricant composed of the lubricant paint 71e is used. As shown in FIG. 1B, the layer is brought into contact with the surface of the photoreceptor 1 together with the edge portion 71f of the blade 71d, thereby achieving the object.

The coating material used in the present invention is preferably a coating material that maintains a low coefficient of friction even when used for a long time, has little change over time, has good compatibility with urethane rubber, does not peel off from the blade side surface, and has abrasion resistance.
Paints include acrylic, urethane, silicone, and fluorine-based normal temperature or thermosetting resins, all of which have advantages and disadvantages in durability, adhesion, lubricity, and coating properties, and are used for cleaning blades. Not suitable for.

When used for a cleaning blade, it is important that the coefficient of friction is low, the printing durability is high, and the change with time of these characteristics is small.
In order to achieve a low coefficient of friction, it is conceivable to disperse a material having lubricity in the paint or separately coat a lubricant such as PTFE or PFA. It is desirable to disperse it in the paint because it is lost and causes problems in durability.

  In the present invention, a thermosetting type in which a fluorine-based resin such as PTFE or PFA is dispersed in a latex-based material having chemical affinity for urethane rubber, excellent adhesion, and good wear resistance. By applying the paint to the blade, particularly excellent characteristics can be obtained.

  PTFE paint is marketed as a paint in which a dispersion of a fluororesin obtained by emulsion polymerization, a nonionic surfactant that disperses the dispersion, and a pigment are mixed. Specifically, Daikin Industries may include Polyflon TFE Enamel EK-4300, ES-5100, and ED-4139BD. In order to improve the adhesion to the base material, it is preferable to use an undercoat paint in which a lower adhesive is blended. In addition, as a PFA paint, there is NEOFLON PFA: Daikin Industries, which has improved workability with respect to PTFE paint such as low melt viscosity and pinhole-free film formation.

  Moreover, as a fluororesin coating material in which latex is used as a binder, Daiel Latex GLS-213 containing modified TFE: manufactured by Daikin Industries, Ltd. may be mentioned. Excellent durability such as non-adhesiveness, lubricity, heat resistance and chemical resistance.

  The blade was brought into contact with the photosensitive member by applying a thermosetting lubricating paint containing fluororesin fine particles to the edge of the side surface of the cleaning blade (the edge was not applied for ensuring cleaning properties). The frictional resistance at the time can be reduced to the extent that the rotation of the photosensitive member and the edge of the cleaning blade are not distorted, and the durability of the cleaning blade is ensured, so that it can withstand long-term use.

  As means for applying the lubricating paint, 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 lubricating paint 71e from being attached to the blade edge and unnecessary surfaces, a seal is pasted and sprayed on the surface facing the photoreceptor and the surface not coated.
In the case of the dipping coating method, dipping is performed so that the surface facing the photoconductor faces up and does not touch the edge, or one surface is dipped so that the surface facing the photoconductor is not immersed in the lubricating paint 71e (single surface In this case, the process is completed here), and one side is further immersed (in the case of double-sided coating). In this case as well, a seal is applied as necessary. Thereafter, the surface facing the photoreceptor is faced up and dried at a temperature of room temperature to 40 ° C., dried to some extent, and then heated and dried at a temperature of 100 to 150 ° C. for about 20 to 40 minutes.

The thin film can be formed by the lubricating coating 71e on one side or both sides. Since the mechanical strength of the blade edge is increased by coating, the surface of the photoreceptor is surely contacted. It becomes even stronger and is effective in improving the prevention of spherical toner such as polymerized toner and mixed fine particles having an average particle size of less than the average particle size. However, it is necessary to consider according to the hardness, free length, thickness, etc. of the blade. If the wall thickness is thin, the hardness is small, or the free length is long, double-sided coating is desirable.
As a result, the coefficient of friction of the lubricating paint on the thin film shows a numerical value between 0.25 and 0.4 as measured by the Euler belt method. The rubbing is performed smoothly.

  When the blade edge 71f is applied so that the paint is applied, the frictional resistance when rubbing against the photosensitive member is reduced, but the risk of the edge function being lowered and the toner blocking rate being reduced is increased, and the polymerized toner having a high degree of circularity. (Spherical toner) falls into a state where it can hardly be cleaned.

  As shown in FIG. 1B, the application range on the side surface of the blade 72d is such that the lubricating paint 71e contacts the photoconductor 1 simultaneously with the edge portion 71f according to the angle when the cleaning blade 71 contacts the photoconductor 1. The position that can be formed is an end portion on the edge 71f side (in the figure, a position corresponding to the distance La from the edge portion 71f), and the lubricating paint 71e is applied from this position.

The application range of the lubricating paint 71e is effective until just before applying to the edge by satisfying the above-described conditions, L2 in FIG. 3 represents the non-application width of the paint from the edge, and L2 is 0 <L2 <1. (Mm), in particular, L2 is preferably 0.05 to 0.5 mm. The narrower the non-application width L2 from the edge (closer to 0 mm), the higher the effectiveness.
As shown in the side view of the cleaning blade 72, the lubricating paint 71e is applied to one side or both sides of the blade 72d as shown in FIGS.
In FIG. 4, 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 photoconductor when abutting against the photoconductor, as shown in FIG. In addition, it is sufficient that the coating width L1 is 2 mm or more in consideration of coating properties and the like. When the cleaning blade 71 is in operation, a load (contact pressure) of about 25 (g / cm) is applied, so that the tip of the blade 71d (the portion where the end surface indicated by reference numeral 71f1 in the figure is located) is bent ( It touches the photoconductor with a bend.
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. That is, an effect of reducing the frictional resistance with the photosensitive member occurs.

  L1 can sufficiently achieve the expected performance if the paint is applied to one side of the blade 71d, but the mechanical strength of the blade 71d can be increased by applying the paint to both sides. Therefore, it can be further strengthened and effective in improving the cleaning property.

FIG. 6 shows a state in which the blade edge 71 f is in sliding contact with the photosensitive member 1, similarly to the state shown in FIG.
In this figure, the lubricating coating 71e is in sliding contact with the photoreceptor 1, whereby the frictional resistance with the photoreceptor 1 is reduced, and a part of the lubricant contained in the paint 71e is transferred to the photoreceptor 1. The friction coefficient of the photoreceptor 1 is also reduced.

  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 leak (cleaning failure).

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)).

  7 and 8 show that the thickness of the blade is 8 mm from the edge by spray coating so that the thickness of the coating film is about 100 μm on urethane rubber having a thickness of 2 mm and a JIS-A hardness of 68 °. It is an example of measurement of the surface roughness at a position of 2 to 3 mm from the edge after coating over the entire length. The results shown in FIG. 7 were as follows: Rz was 0.8296 μm, Rmax was 1.154 μm, and in FIG. 8, Rz was 1.28776 μm and Rmax was 2.146 μm.

When used as a cleaning blade, there is no drum squeal, and even if spherical toner (average circularity 0.978, toner particle size 6.8 μm) is used, about 1,000 copies can be cleaned from the beginning. ing.
As the lower limit of the surface roughness, if Rz is 0.1 μm or more and Rmax is 0.5 μm or more, the frictional resistance between the photoreceptor and the blade can be lowered to such an extent that the cleaning performance is not hindered. Most commonly used toner particle sizes of 4 to 8 (μm) can be dealt with.

  The film thickness of the coating film after heat drying depends on the hardness, thickness, and load (contact thickness) of the urethane rubber, but is preferably 20 μm or more and 100 μm or less. A preferable range is about 30 to 80 μm. If it is thinner than 20 μm, the abrasion resistance of the coating film will increase. If it is thicker than 100 μm, the blade edge will float, causing a problem in adhesion to the photoreceptor, and there is a risk that the cleaning properties of the residual powder will deteriorate. .

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. Tend to be a little weak in the 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.

  The contact with the photosensitive member when the cleaning blade 71 is attached is a counter contact as shown in FIG. The contact angle θ with respect to the photosensitive member is important for maintaining good cleaning properties, and the contact angle θ of the cleaning blade 71 used in the present invention is not possible even if it is 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 °. Even within the range of each contact θ, the application range from the edge 71f and the thickness of the coating film are defined so that the edge 71f of the blade 71d and the lubricating paint 71e simultaneously contact the photoreceptor. Is done.

  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.
(2) Cleaning Device and Image Forming Apparatus FIG. 10 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. 10 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 is deteriorated because the nip cannot be obtained, but there is an advantage that it is not limited to the hardness of the charging member used.

  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 diameter 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 been described in the background art, as shown in FIGS. 21 and 22, the pulverized toner has an irregular shape (average circularity is about 0.9), and is therefore advantageous for cleaning. 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 to the sheet transported from the paper feed tray 10 by the transfer device 5 (in FIG. 10, a roller shape, but a corona charger or a belt-like transfer device can also be used). The image is transferred to a transfer body (copy paper) 11, separated from the photoreceptor 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. 10, 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 made dense over the entire surface of the roller, but as shown in FIG. 12, 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. 10 are incorporated into one image forming apparatus as shown in FIG. Many devices (printers and copiers) are used.

  The quadruple tandem image forming apparatus illustrated in FIG. 13 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 the cleaning blade of the present invention is mounted on a process cartridge that is detachable from the image forming apparatus will be described with reference to FIG.
(3) 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. 14 shows a process cartridge including a cleaning device 7 in which a charging member (charging roller) 2, a developing device 4, and a cleaning blade 71 are disposed around the photosensitive member 1.

  FIG. 15 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 photosensitive member 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.

Next, a photoconductor for forming a latent image will be described.
(4) Outline of Photoreceptor The photoreceptor 1 used in the present invention can basically use any of the configurations shown in FIGS.
FIG. 16 shows a function-separated organic photoconductor composed of a conductive support 101, an undercoat layer 102, a charge generation layer 103, and a charge transport layer 104. The undercoat layer 102 is set to about 2 to 20 μm, the charge generation layer 103 is set to about 0.1 to 0.5 μm, and the charge transport layer 104 is set to 10 to 50 μm. When polycarbonate resin is used for the charge transport layer 104, the durable number is about 40,000 to 80,000 sheets in terms of A4 size paper.

  FIG. 17 shows a structure in which a protective layer having a high wear resistance of about 2 to 10 μm or a second charge transport layer 105 is further formed on the charge transport layer 104 in order to improve the repeated durability. Although the number of durable sheets varies depending on the specification, it can have a durability of about one million sheets or more.

FIG. 18 is a configuration diagram of a photoreceptor in which a photosensitive layer 106 in which the functions of the charge generation layer 103 and the charge transport layer 105 are further layered is formed.
In the present invention, the function-separated organic photoreceptor 1 shown in FIGS. 16 and 17 is mainly used from the viewpoints of durability, sensitivity, and repetitive stability.
Hereinafter, the function-separated type photoreceptor used in the present invention will be described in detail.
"1" conductive support (101)
As the conductive support 101 usable for the photoreceptor, there are many types such as a metal such as duralumin, aluminum, copper, brass, and stainless steel, a plastic material, a paper tube, and an insulating material such as glass. However, among them, a lightweight JIS standard 3003 type aluminum alloy which is excellent in mechanical strength, workability (cutting property), electrical characteristics and the like required as a conductive support is preferable.

  The aluminum support as a photoconductor is cut so that the characteristics such as roundness, straightness, and runout are within the specified values, and the surface finish (superfinishing) is finally achieved so that the surface roughness is about 1 to 10 μm. And mirror finish).

The conductive support 101 configured as an organic photoreceptor is processed to have a thickness of 0.6 to 3 mm and an outer diameter of about 25 to 100 (mm). It is sufficient that the electrical resistance of the conductive support 101 is 10 ⁶ Ω · cm or less in terms of volume resistivity, and if the volume resistivity is on the order of about 10 ⁹ Ω · cm, it can be used without damaging the electrophotographic characteristics. it can. As the electric resistance increases, the movement of holes in the photosensitive layer is hindered, so that the light attenuation characteristic becomes gradual and the electrophotographic characteristics deteriorate.

In aluminum, an insulating oxide film (Al ₂ O ₃ ) is formed immediately after cutting, but the oxide film formed in the atmosphere is thin, weak, and non-uniform, so that the charge injection blocking film (as a charge injection layer) It is insufficient as a blocking film. Therefore, it is a thin film (undercoat layer, intermediate described later) that has an anodizing treatment or that retains the time (up to several tens of msec) until the development is completed (charge during negative charge). Also referred to as a layer).
"2" undercoat layer (102)
The purpose of forming the undercoat layer 102 is to prevent charge injection from the conductive support side during charging, and to prevent incident light during image formation from being reflected by the conductive support and re-entering the photosensitive layer. By doing so, image disturbance is eliminated, and a charging potential, electrostatic contrast and uniform image (moire prevention, dot pattern reproduction, etc.) necessary for image formation are ensured. Therefore, it is indispensable for a digital image forming apparatus. In general, the thickness of the undercoat layer 102 is set to about 1 to 10 [mu] m, preferably 3 to 6 [mu] m, from the viewpoint of preventing charge injection and not deteriorating electrophotographic characteristics.

The undercoat layer is set to a volume resistivity on the order of 10 ¹⁰ to 10 ¹³ (Ω · cm), but as the film thickness increases, electrons formed by image formation are transferred from the undercoat layer 102 to the conductive support. It takes time to move to the 101 side. Therefore, when it is used repeatedly, electrons accumulate at the interface between the undercoat layer and the charge generation layer, which becomes a residual potential, causing deterioration of light attenuation characteristics and an increase in image area potential, resulting in a decrease in contrast potential and image density. Deterioration and afterimages are likely to occur.

  On the other hand, as the thickness of the undercoat layer is reduced, unevenness is likely to be formed in the coating film, and charge injection from the conductive support (in this case, positive charges (holes)) is likely to occur. While charging becomes insufficient, abnormal images such as black spots, white spots, and uneven density are caused, resulting in a noisy image. Therefore, the film thickness is preferably about 3 to 6 μm.

  The resin used for the undercoat layer includes water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane resins, melamine resins, and alkyd-melamines. Examples thereof include curable resins that form a three-dimensional network structure, such as resins and epoxy resins. Further, fine powders such as metal oxides exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like, or metal sulfides and metal nitrides may be dispersed and contained. These undercoat layers can be formed using an appropriate solvent and coating method.

Furthermore, a metal oxide layer formed by, for example, a sol-gel method using a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like is also useful as the undercoat layer of the present invention.
"3" charge generation layer (103)
The charge generation layer 103 is a layer that generates electron-hole pairs necessary for image formation by photons irradiated from the image exposure apparatus 3, and the sensitivity tends to increase as the amount of generated electron-hole pairs increases. In order to smoothly move electrons or holes generated by image exposure toward the surface or the charge of the conductive support 101, the charge transport layer 104 or the undercoat layer 102 in contact with the charge generation layer 103 It is desirable that the barrier at the interface be as low as possible, and any material can be used regardless of whether it is an inorganic material or an organic material, as long as the photosensitive material satisfies this condition.

Examples of the charge generating material of the inorganic material include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compound, and amorphous silicon.
Further, organic charge generating materials include metal phthalocyanine, phthalocyanine pigments such as metal-free phthalocyanine, azulenium salt pigments, squaric acid methine pigments, azo pigments having a carbazole skeleton, azo pigments having a triphenylamine skeleton, An azo pigment having a diphenylamine skeleton, an azo pigment having a dibenzothiophene skeleton, an azo pigment having a fluorenone skeleton, an azo pigment having an oxadiazol skeleton, an azo pigment having a bis-stilbene skeleton, an azo pigment having a distyryl oxadiazol skeleton Azo pigments having a distyrylcarbazole skeleton, perylene pigments, anthraquinone or polycyclic quinone pigments, quinoneimine pigments, diphenylmethane and triphenylmethane pigments, benzoquinone and naphthoquinone pigments, cyanine and the like Azomethine pigments, indigoid pigments, bisbenzimidazo - there and Le pigments.

  The binder resin used as necessary for the charge generation layer 103 is polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, polyarylate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N. -Vinylcarbazole, polyacrylamide, etc. are used. These binder resins can be used alone or as a mixture of two or more. Further, a low molecular charge transport material (electron transport material or hole transport material) may be added as necessary.

  Examples of the electron transporting material include chloroanil, bromanyl, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2,4 , 5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophen-4-one, 1,3,7-tri Examples thereof include electron accepting substances such as nitrodibenzothiophene-5,5-dioxide. These electron transport materials can be used alone or as a mixture of two or more.

Examples of the hole transport material include electron donating materials shown below.
For example, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, 9- (p-diethylaminostyrylanthracene), 1,1-bis- (4-dibenzylaminophenyl) propane, styrylanthracene, styryl Examples include pyrazoline, phenylhydrazones, α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, and thiophene derivatives. These hole transport materials can be used alone or as a mixture of two or more.

  The charge generation layer 103 is formed of a charge generation material, a solvent, and a binder resin as main components, and includes any additive such as a sensitizer, a dispersant, a surfactant, and silicone oil. May be included.

  As a method for forming the charge generation layer 103, a vacuum thin film manufacturing method and a casting method from a solution dispersion system can be mentioned. As the former method, a vacuum deposition method, a glow discharge decomposition method, an ion plating method, a sputtering method, a reactive sputtering method, a CVD method, or the like is used, and the above-described inorganic materials and organic materials can be satisfactorily formed. In addition, in order to provide the charge generation layer 103 by the casting method, if the inorganic or organic charge generation material described above is required, a solvent such as tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, or butanone is used together with a binder resin to form a ball mill, an atom, or the like. It can be formed by dispersing with a lighter, sand mill or the like, and applying the solution after diluting the dispersion appropriately. The coating can be performed using a dip coating method, a spray coating method, a bead coating method, or the like.

The film thickness of the charge generation layer 103 provided as described above is suitably about 0.01 to 5 μm, preferably 0.05 to 2 μm. Usually, it is applied to a thickness of 0.1 to 0.3 μm.
If the film thickness is too thin, poor sensitivity occurs, but if it is too thick, light attenuation deterioration due to space charge and a residual potential increase occur, leading to image quality deterioration such as image density reduction and resolution reduction.
"4" charge transport layer (1) (104)
The charge transport layer (1) 104 is formed to ensure a sufficient charging potential and a sufficient contrast potential necessary for image formation. The charge transport layer (1) 104 generally has little polarity dependence, and polycarbonate resin (A type, C type, Z type, etc.) having a volume resistivity of about 10 ¹⁴ to 10 ¹⁸ (Ω · cm), styrene Resins, amorphous polyolefin resins, and the like are used as binder resins, and donors, antioxidants, leveling materials, and the like are further added.
As the low-molecular charge transport material constituting the charge transport layer (1) 104, an oxazole derivative, an oxadiazole derivative, an imidazole derivative, a triphenylamine derivative, an α-phenylstilbene derivative, a toniphenylmethane derivative, an anthracene derivative, or the like is used. I can do it.

On the other hand, as the polymer charge transport material, the following known polymer charge transport materials can be used. For example,
[1] Polymers having a carbazole ring in the main chain and / or side chain include, for example, poly-N-vinylcarbazole, JP-A-50-82056, JP-A-54-9632, and JP-A-54. No. 11737, JP-A-4-183719, and the like.
[2] Examples of the polymer having a hydrazone structure in the main chain and / or side chain include compounds described in JP-A-57-78402 and JP-A-3-50555.
[3] Examples of the polysilylene polymer include compounds described in JP-A-63-285552, JP-A-5-19497, and JP-A-5-70595.
[4] Polymers having a tertiary amine structure in the main chain and / or side chain include, for example, N, N-bis (4-methylphenyl) -4-aminopolystyrene, JP-A-1-13061, Compounds described in Kaihei 1-19049, JP-A-1-1728, JP-A-1-105260, JP-A-2-167335, JP-A-5-66598, and JP-A-5-40350 Etc.
[5] Other polymers include, for example, formaldehyde condensation polymers of nitropyrene, compounds described in JP-A Nos. 51-73888 and 56-150749, and the like.
The polymer having an electron donating group used in the present invention is not limited to the above polymer, but also a copolymer of known monomers, a block polymer, a graft polymer, a star polymer, and, for example, It is also possible to use a crosslinked polymer having an electron donating group as disclosed in JP-A-3-109406.

    Further, as the polymer charge transport material in the present invention, a polycarbonate having a triarylamine structure in the main chain and / or side chain is effectively used.

  On the other hand, examples of the polymer compound that can be used as the binder component include polystyrene, styrene / acrylonitrile copolymer, styrene / butadiene copolymer, styrene / maleic anhydride copolymer, polyester resin, polyvinyl chloride, and chloride. Vinyl / vinyl acetate copolymer, polyvinyl acetate, polyvinylidene chloride, polyarylate resin, polycarbonate resin (bisphenol A type, bisphenol C type, bisphenol Z type or copolymers thereof), cellulose acetate resin, ethyl cellulose resin, polyvinyl Thermoplastic or thermal such as butyral, polyvinyl formal, polyvinyl toluene, acrylic resin, silicone resin, fluorine resin, epoxy resin, melamine resin, urethane resin, phenol resin, alkyd resin Including but of resin, but is not limited thereto. These polymer compounds can be used singly or as a mixture of two or more kinds, or copolymerized with a charge transport material.

  Examples of the dispersion solvent that can be used in preparing the charge transport layer coating solution include ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, and cyclohexanone, ethers such as dioxane, tetrahydrofuran, and ethyl cellosolve, toluene, xylene, and the like. Examples include aromatics, halogens such as chlorobenzene and dichloromethane, and esters such as ethyl acetate and butyl acetate, but it is desirable to avoid the use of halogen-based solvents in consideration of environmental destruction.

  In the present invention, for the purpose of improving the environmental resistance, and for the purpose of preventing a decrease in sensitivity and an increase in residual potential, oxidation is performed on each layer such as a charge generation layer, a charge transport layer, an undercoat layer, a protective layer, and an intermediate layer. Inhibitors, plasticizers, lubricants, UV absorbers, and low molecular charge transport materials can be added.

The film thickness of the charge transport layer (1) 104 is set in the range of about 10 to 40 μm, but is preferably in the range of 10 to 30 μm, and is set to about 15 to 25 μm when high resolution is desired.
When the film thickness is 10 μm or less, the electrostatic capacity becomes too large, and it becomes difficult to ensure the surface potential necessary for image formation. The contrast potential required for image formation is desirably at least 250 V or more, but if it is 10 μm or less, it is difficult to ensure the contrast potential, and the photosensitive layer is worn away by repeated use, so that the actual use time is short and the practicality is poor. .
Further, if the film thickness is thin, it is difficult to produce a photosensitive layer having a uniform film thickness, image defects due to density unevenness and pinholes occur, and the image quality is poor.

When the thickness of the charge transport layer (1) 104 is increased, the electrostatic capacity is reduced, so that a sufficient surface potential is ensured and an image quality with a good SN ratio can be obtained. However, increasing the thickness relatively increases the number of structural defects in the photosensitive layer, which hinders the movement of carriers (here, holes) and causes undesirable phenomena such as afterimages.
Due to the formation of the charge transport layer (1) 104, the number of durable sheets is 40 to 80,000, and the durability can be further increased by using the cleaning blade of the present invention.

In the present invention, as shown in FIG. 17, it is also possible to use a photoreceptor in which a charge transport layer (2) 105 is further formed on the charge transport layer 104.
The charge transport layer (2) 105 is formed for the purpose of improving the durability of the four-layered photoreceptor shown in FIG.
[6] Charge transport layer (2) (105)
The charge transport layer (2) 105 is formed for the purpose of enhancing the durability of the photoreceptor. In order to be repeatedly used as a photoreceptor, it must satisfy electrophotographic characteristics. Therefore, the charge transport layer (2) 105 is required to have appropriate electrical resistance, good hole mobility, and high durability.

The charge transport layer (2) 105 has a volume resistivity of about 10 ¹² to 10 ¹⁴ Ω · cm, high hole mobility (10 −5 or more (cm ² / v · sec)), and translucency. A thin film having a thickness of about 0.5 to 10 μm is desirable.
For this purpose, the charge transport layer 105 is desirably a photosensitive layer on the extension of the charge transport layer 104, and is configured so that a clear interface is not formed between the two layers at the time of layer formation, so that it can be used repeatedly. The barrier between the interface of the charge transport layer 104 and the charge transport layer 105 is lowered, and it is possible to suppress the accumulation of residual potential, deterioration of light attenuation characteristics, and reduction in charging potential.

  In order to make the electrophotographic characteristics equal to those of the charge transport layer (1) 104 and improve the abrasion resistance of the charge transport layer 105, titanium oxide, alumina, silica, etc. having an average particle size of 0.1 μm or less are used as the binder resin of the photosensitive layer. There are a method of adding an N-type filler, a method of using a cross-linked resin for the charge transport layer (2) 105 (thermal curing, photocuring, etc.), and the like.

  In the case of a photoreceptor in which a filler is added to the binder resin of the photosensitive layer, the average particle diameter is 0.7 μm or less and 0.1 μm or more together with the donor in the binder resin having the charge transport layer (2) 105 as a constituent material. Preferably, a filler of 0.5 μm to 0.2 μm is dispersed. If necessary, a small amount of an antioxidant or a plasticizer is added as a property improving agent.

Fillers include organic fillers (fluorine resin powders such as polytetrafluoroethylene, silicon resin powders, amorphous carbon powders, etc.), inorganic fillers (metal powders such as copper, tin, aluminum and indium, silica Metal oxides such as tin oxide, zinc oxide, titanium oxide, alumina, indium oxide, antimony oxide, bismuth oxide, calcium oxide, tin oxide doped with antimony, indium oxide doped with tin, tin fluoride Metal fluorides such as calcium fluoride and aluminum fluoride, potassium titanate, boron nitride, and the like).
Among the fillers described above, a material having water repellency and a volume specific resistance of about 10 ¹⁰ to 10 ¹³ (Ω · cm), particularly alumina and titanium oxide can be preferably used. The coating method includes a spray method and a dipping method.

On the other hand, when a crosslinking type resin is used as the binder resin, a light (ultraviolet light) or thermosetting type crosslinking type is desirable.
A case where a thermosetting type cross-linked resin is used will be described.
In the method using a crosslinkable resin as the binder resin, the charge transport layer 105 includes a “crosslinkable charge transport material having a reactive hydroxyl group”, a “thermosetting resin monomer”, and a “thermosetting surfactant”. A resin obtained by a crosslinking reaction with is used.

Heating and crosslinking increase the hardness and form a photoreceptor with excellent wear resistance.
Examples of the crosslinkable charge transport material include bisphenol compounds described in JP-A-7-228557, diamine compounds described in JP-A-8-198825, JP-A-9-31035, JP-A-9-26369, Dihydroxyl group-containing diamine compounds described in JP-A-9-268164 and the like, JP-A-9-278723, JP-A-10-7630, hydroxyl-group-containing amine compounds, JP-A-9-194442 The hydroxyl group-containing stilbene compounds described above and the amine compounds described in JP-A No. 10-53569 are effective. These are raw materials for polymer charge transport materials, exhibiting excellent characteristics in charge transport ability and excellent in reactivity.

  Examples of thermosetting resin monomers include melamine resins, urea resins, epoxy resins, urethane resins, alkyd resins, acrylic resins, condensates such as organic silane condensates, and mixtures thereof, which are effective in the present invention. Can be used for For example, melamine resin has the property of having a self-condensation property, can easily adjust the blending ratio with other raw materials, and has a high degree of design freedom. Epoxy resins also have a high degree of design freedom because there are many types of curing agents.

As a thermosetting surfactant, for example,
(1) As a copolymer containing a (meth) acrylate having a fluoroalkyl group described in JP-A-7-68398, fluorine described in JP-A-60-212410 and JP-A-60-228588 A block copolymer comprising a vinyl-type monomer containing no fluorine and a fluorine-containing vinyl-type monomer,
(2) As a graft graft polymer, for example, a comb-shaped graft polymer obtained by copolymerizing a methacrylate macromonomer having a polymethyl methacrylate side chain and a (meth) acrylate having a fluoroalkyl group described in JP-A-60-187721 and so on.

These fluorine-based resins are easily available as resin addition amounts. For example, fluorine-containing random copolymers are available from Asahi Kasei Co., Ltd. under the names of resin surface modifiers SC-101 and SC-105, As a fluorine-containing block copolymer, as a block copolymer composed of a fluorinated alkyl group-containing polymer segment and an acrylic polymer segment, Modiper F series F100, F110, F200, F210, F2020, etc. from Nippon Oil & Fats Co., Ltd. As the fluorine-based graft polymer under the trade name, they are commercially available from Toagosei Co., Ltd. under the trade names Aron GF-150, GF-300, and RESEDA GF-2000.
These surfactants may be used alone or as a crosslinked resin component.

JP 2000-119354 A describes a material in which a silicone component is chemically bonded to a fluororesin, and hydrophobic resins ZX series ZX-007C, ZX-001, ZX-017, etc. are particularly excellent in stain resistance. It has the characteristics.
When used as a cross-linked resin component, a copolymer of a methacrylic acid ester and a fluorinated alkyl acrylate is particularly effective.

In forming the charge transport layer, a low-molecular compound such as an antioxidant, a plasticizer, and an ultraviolet absorber, and a leveling agent can be added.
These compounds can be used alone or as a mixture of two or more. The amount of the low molecular compound used is 0.1 to 50 parts by weight, preferably 0.1 to 20 parts by weight, based on 100 parts by weight of the resin component, and the amount of the leveling agent used is 100 parts by weight of the resin component. About 0.001 to 5 parts by weight is appropriate.

Use of a fluorosurfactant contributes to increasing the hardness of the photoreceptor, and at the same time lowers the friction coefficient of the photoreceptor surface layer.
Therefore, corona products such as ozone and nitrogen oxide, which are generated when the photosensitive member is charged in the image forming apparatus, are extremely effective in improving the friction coefficient and the cleaning failure that are increased. .

When a crosslinkable resin is used, it is necessary to bond a charge transporting functional group to the crosslinkable resin to such an extent that photoinduced charge carriers can move in the protective layer, or to blend a polymer charge transport material.
If it is possible to mix the low molecular charge transport material and the cross-linked resin, the low molecular charge transport material may be mixed, but it cannot be fixed in the protective layer, and the low molecular component is on the surface. May precipitate. By using the above-described polymer charge transport material for such a case, precipitation can be prevented and sensitivity characteristics can be improved.

  Methods for forming the photosensitive layer include dipping method, spray coating method, ring coating method, roll coater method, gravure coating method, nozzle coating method, screen printing method, etc. A suitable method is taken into consideration. In the case of forming the charge transport layer 105, the spray coating method and the ring coating method are particularly preferable because they are easy to ensure quality stability in production.

  In the charge transport layer described in the present invention, for example, it is effective to add a leveling agent as a means for smoothening the surface of the photosensitive layer by eliminating the roughness. As the leveling agent, a known material can be used, but a silicone oil-based leveling agent that can impart a high level of smoothness in a small amount and has a small influence on electrostatic characteristics is particularly preferable. Examples of silicone oils include dimethyl silicone oil, methyl phenyl silicone oil, methyl hydrogen polysiloxane, cyclic dimethyl polysiloxane, alkyl modified silicone oil, polyether modified silicone oil, alcohol modified silicone oil, fluorine modified silicone oil, amino modified Examples include silicone oil, mercapto-modified silicone oil, epoxy-modified silicone oil, carboxyl-modified silicone oil, higher fatty acid-modified silicone oil, and higher fatty acid-containing silicone oil. It is also possible to reduce the unevenness depending on the coating conditions. For example, in dip coating, when the surface of the coating film is still wet after it has been lifted, unevenness is reduced by covering it with a hood so that the surface is not disturbed by the flow of wind. The Also, if the solvent near the coating surface suddenly volatilizes, only the surface is cured and the inside of the coating film becomes fluid, and the coating film inside may sag and form irregularities. In a wet state, a vapor layer of a solvent is formed around the photoconductor, and the solvent is gently volatilized to promote leveling, thereby reducing unevenness and smoothing.

  In addition, in spray coating, when forming a coating film by air spray, by controlling the air pressure and air flow to an appropriate amount, surface irregularities can be suppressed while the coating film is in a fluid state. It is necessary to suppress. Here, if the air pressure and air flow rate are too large, the surface of the coating will be disturbed by the air flow, and conversely if it is too small, the coating liquid droplets may not be uniform or atomization may be insufficient. As a result, the uniformity of the coating film is reduced. Further, after the charge transport layer is formed, the solvent is volatilized while rotating, but if the rotation speed at this time is too high, centrifugal force is applied to the coating film that still contains the solvent and has fluidity, and the unevenness is emphasized. On the other hand, if the rotational speed is too low, the influence of dripping due to gravity is superior to the leveling due to rotation, which causes unevenness. For this reason, it is necessary to set the rotation speed of the photoreceptor in a wet state to an appropriate value.

  Furthermore, in spray coating, it is important that the liquid feeding of the pump that supplies the coating liquid is constant. That is, if the supply of liquid is not constant but has pulsation, it directly affects the discharge amount of the liquid, resulting in unevenness in the amount of adhesion. Therefore, as the pump for supplying the liquid to the spray, it is preferable to use a multiple plunger pump with suppressed pulsation, a syringe-type ultra-precise discharge device, or the like.

These methods may be used singly, but by combining a plurality of methods, leveling is more effectively performed and a charge transport layer with reduced unevenness is formed. Further, if leveling is insufficient, it is possible to wear the convex portions of the charge transport layer and wear them as a method for reducing the irregularities. For example, a method of detecting a convex portion with a film thickness meter and polishing the portion to eliminate the convex portion can be considered.
In the present invention, for the purpose of improving environmental resistance and preventing the decrease in sensitivity and the increase in residual potential, oxidation is performed on each layer such as a charge generation layer, a charge transport layer, an undercoat layer, a protective layer, and an intermediate layer. Inhibitors, plasticizers, lubricants, UV absorbers, and low molecular charge transport materials can be added. Representative materials of these compounds are described below.
Examples of the antioxidant that can be added to each layer include, but are not limited to, the following.
(A) Phenolic compounds 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, n-octadecyl -3- (4'-hydroxy-3 ', 5'-di-t-butylphenol), 2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2,2'- Methylene-bis- (4-ethyl-6-tert-butylphenol), 4,4′-thiobis- (3-methyl-6-tert-butylphenol), 4,4′-butylidenebis- (3-methyl) -6-tert-butylphenol), 1,1,3-tris- (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6- Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis- [meth -3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, bis [3,3′-bis (4′-hydroxy-3′-t-butylphenyl) ) Butyric acid] cricol ester, tocopherols and the like.
(B) Paraphenylenediamines N-phenyl-N′-isopropyl-p-phenylenediamine, N, N′-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl-p-phenylene Diamine, N, N′-di-isopropyl-p-phenylenediamine, N, N′-dimethyl-N, N′-di-t-butyl-p-phenylenediamine and the like.
(C) Hydroquinones 2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-octyl-5-methylhydroquinone, 2 -(2-octadecenyl) -5-methylhydroquinone and the like.
(D) Organic sulfur compounds Dilauryl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, ditetradecyl-3,3′-thiodipropionate, and the like.
(E) Organic phosphorus compounds Triphenylphosphine, tri (nonylphenyl) phosphine, tri (dinonylphenyl) phosphine, tricresylphosphine, tri (2,4-dibutylphenoxy) phosphine and the like.
Examples of the plasticizer that can be added to each layer include, but are not limited to, the following.
(A) Phosphate ester plasticizer Triphenyl phosphate, tricresyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, trichloroethyl phosphate, cresyl diphenyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate, Triphenyl phosphate etc.
(B) Phthalate ester plasticizers Dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, diheptyl phthalate, di-2-ethylhexyl phthalate, diisooctyl phthalate, di-n-octyl phthalate, phthalate Dinonyl acid, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, ditridecyl phthalate, dicyclohexyl phthalate, butyl benzyl phthalate, butyl lauryl phthalate, methyl oleyl phthalate, octyl decyl phthalate, dibutyl fumarate, dioctyl fumarate Such.
(C) Aromatic carboxylate plasticizers Trioctyl trimellitic acid, tri-n-octyl trimellitic acid, octyl oxybenzoate, and the like.
(D) Aliphatic dibasic ester plasticizer dibutyl adipate, di-n-hexyl adipate, di-2-ethylhexyl adipate, di-n-octyl adipate, adipic acid n-octyl-n-decyl , Diisodecyl adipate, dicapryl adipate, di-2-ethylhexyl azelate, dimethyl sebacate, diethyl sebacate, dibutyl sebacate, di-n-octyl sebacate, di-2-ethylhexyl sebacate, di-2 sebacate -Ethoxyethyl, dioctyl succinate, diisodecyl succinate, dioctyl tetrahydrophthalate, di-n-octyl tetrahydrophthalate and the like.
(E) Fatty acid ester derivatives: butyl oleate, glycerol monooleate, methyl acetylricinoleate, pentaerythritol ester, dipentaerythritol hexaester, triacetin, tributyrin, and the like.
(F) Oxyacid ester plasticizers Methyl acetyl ricinoleate, butyl acetyl ricinoleate, butyl phthalyl butyl glycolate, tributyl acetyl citrate and the like.
(G) Epoxy plasticizer Epoxidized soybean oil, epoxidized linseed oil, epoxy butyl stearate, decyl epoxy stearate, octyl epoxy stearate, benzyl epoxy stearate, dioctyl epoxy hexahydrophthalate, didecyl epoxy hexahydrophthalate, etc. .
(H) Dihydric alcohol ester plasticizers Diethylene glycol dibenzoate, triethylene glycol di-2-ethylbutyrate and the like.
(J) Chlorinated plasticizers Chlorinated paraffin, chlorinated diphenyl, chlorinated fatty acid methyl, methoxychlorinated fatty acid methyl and the like.
(K) Polyester plasticizer Polypropylene adipate, polypropylene sebacate, polyester, acetylated polyester, etc.
(L) Sulfonic acid derivatives P-toluenesulfonamide, O-toluenesulfonamide, P-toluenesulfoneethylamide, O-toluenesulfoneethylamide, toluenesulfone-N-ethylamide, P-toluenesulfone-N-cyclohexylamide and the like.
(M) Citric acid derivatives Triethyl citrate, triethyl acetyl citrate, tributyl citrate, tributyl acetyl citrate, tri-2-ethylhexyl acetyl citrate, acetyl citrate-n-octyldecyl and the like.
(N) Others Terphenyl, partially hydrogenated terphenyl, camphor, 2-nitrodiphenyl, dinonylnaphthalene, methyl abietate and the like.

In the present invention, a lubricant can be added to each layer. Examples thereof include the following, but are not limited thereto.
(A) Hydrocarbon compounds Liquid paraffin, paraffin wax, microwax, low-polymerized polyethylene and the like.
(B) Fatty acid compounds Lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid and the like.
(C) Fatty acid amide compounds Stearylamide, palmitylamide, oleinamide, methylenebisstearamide, ethylenebisstearamide and the like.
(D) Ester compounds Lower alcohol esters of fatty acids, polyhydric alcohol esters of fatty acids, fatty acid polyglycol esters, and the like.
(E) Alcohol compounds Cetyl alcohol, stearyl alcohol, ethylene glycol, polyethylene glycol, polyglycerol and the like.
(F) Metal soap Lead stearate, cadmium stearate, barium stearate, calcium stearate, zinc stearate, magnesium stearate and the like.
(G) Natural wax Carnauba wax, candelilla wax, beeswax, whale wax, ivotaro, montan wax and the like.
(H) Others Silicone compounds, fluorine compounds, etc.
Examples of the ultraviolet absorber that can be added to each layer include, but are not limited to, the following.
(A) Benzophenone series 2-hydroxybenzophenone, 2,4-dihydroxybenzophenone, 2,2 ′, 4-trihydroxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2,2′-dihydroxy-4- Such as methoxybenzophenone.
(B) Salsylates Phenyl salsylates, 2,4 di-t-butylphenyl 3,5-di-t-butyl 4-hydroxybenzoate, and the like.
(C) Benzotriazole series (2′-hydroxyphenyl) benzotriazole, (2′-hydroxy5′-methylphenyl) benzotriazole, (2′-hydroxy5′-methylphenyl) benzotriazole, (2′-hydroxy3) '-Tertiarybutyl 5'-methylphenyl) 5-chlorobenzotriazole (d) cyanoacrylate type ethyl-2-cyano-3,3-diphenyl acrylate, methyl 2-carbomethoxy 3 (paramethoxy) acrylate, and the like.
(E) Quencher (metal complex)
Nickel (2,2′thiobis (4-t-octyl) phenolate) normal butylamine, nickel dibutyldithiocarbamate, nickel dibutyldithiocarbamate, cobalt dicyclohexyldithiophosphate and the like.
(F) HALS (hindered amine)
Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1- [2- [3- (3 5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6 6-tetramethylpyridine, 8-benzyl-7,7,9,9-tetramethyl-3-octyl-1,3,8-triazaspiro [4,5] undecane-2,4-dione, 4-benzoyloxy- 2,2,6,6-tetramethylpiperidine and the like.
There is.

The Euler belt method for measuring the friction coefficient described in the present invention is measured by the following method.
A photoconductor for measurement is fixed to a pedestal, and a high-quality paper of 85 μm in thickness (made by Ricoh, type 6200 paper, using vertical eyes) cut to a width of 30 mm and a length of 290 mm is used as a belt. Put the weight on one end of the belt, attach a weight of 100 gr to one end of the belt, attach a digital force gauge for weight measurement to the other end, slowly pull the digital force gauge, and measure the weight at the start of belt movement. Read and calculate the (static) friction coefficient μs from Equation 1.

μs = 2 / π × ln (F / W) (Formula 1)
Where μs: static friction coefficient, F: reading load
W: Weight of weight π: Circumference ratio

Examples of the present invention will be described below.
An evaluation photoreceptor in an image forming apparatus in which a cleaning device equipped with a cleaning blade according to this embodiment is used will be described.
(Photoreceptor Preparation Example 1)
Using a JIS3003-based aluminum alloy drum processed to φ30 mm × 340 mm (thickness 0.750 mm) as a conductive support, a coating liquid for an undercoat layer, a coating liquid for a charge generation layer, and a coating for a charge transport layer The working solution was sequentially applied and then dried by heating to form a 3.5 μm undercoat layer, a 0.3 μm charge generation layer, and a 23 μm or 28 μm charge transport layer. The drying conditions were 120 ° C. for 20 minutes for the undercoat layer, and 130 ° C. for 20 minutes for the charge generation layer and the charge transport layer.
The change in the thickness of the charge transport layer was performed by changing the pulling rate from the coating solution.

Among these photoconductors, the photoconductor (photoconductor 1-1) having a charge transport layer of 23 μm is used as a photoconductor for evaluation photoconductor production example 2 described below, and a photoconductor having a charge transport layer of 28 μm. The photoconductor (photoconductor 1-2) is used as a photoconductor for evaluation.
[Coating liquid for undercoat layer]
Alkyd resin (Beccosol 1307-60-EL, manufactured by Dainippon Ink and Chemicals)
10 parts by weight melamine resin (Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals, Inc.)
7 parts by weight Titanium oxide (CR-EL manufactured by Ishihara Sangyo Co., Ltd.) 40 parts by weight Methyl ethyl ketone 200 parts by weight [Coating liquid for charge generation layer]
5 parts by weight of bisazo pigment having the following structure (manufactured by Ricoh)

Polyvinyl butyral (XYHL, manufactured by UCC) 1 part by weight Cyclohexanone 200 parts by weight Methyl ethyl ketone 80 parts by weight [Coating liquid for charge transport layer]
Polycarbonate resin (Z polycarbonate, viscosity average molecular weight; 50,000, manufactured by Teijin Chemicals Ltd.)
10 parts by weight 7 parts by weight of low molecular charge transport material having the following structure

Tetrahydrofuran 100 parts by weight 1% silicone oil (KF50-100CS manufactured by Shin-Etsu Chemical Co., Ltd.) Tetrahydrofuran solution 1 part by weight (Evaluation Photoconductor Preparation Example 2)
Next, spray coating is performed on the photoreceptor 1-1 having a charge transport layer of 23 μm prepared in Preparation Example 1 using the following charge transport layer coating solution, and then heated and dried at 170 ° C. for 30 minutes. A photoreceptor having a 5 μm target charge transport layer 2 laminated thereon was produced.
This photoreceptor is referred to as a photoreceptor 2-1.
[Fluoropolymer-containing charge transport layer coating solution]
3 parts by weight of low molecular charge transport material with the following structure

Fluorosurfactant (Modiper F200, manufactured by NOF Corporation) 2.3 parts by weight
(Solid content: 0.7 parts by weight)
Melamine resin (Super Becamine G-821-60, manufactured by Dainippon Ink and Chemicals)
10.5 parts by weight Tetrahydrofuran 180 parts by weight Cyclohexanone 50 parts by weight The conditions for spray coating of the charge transport layer are as follows.
[Condition for coating the protective layer on the outermost surface of the photoreceptor]
Coating liquid discharge rate: 15 ml / min
Coating liquid discharge pressure: 2.0 kgf / cm ²
Rotating speed of coated drum: 120rpm
Coating speed: 28mm / sec
Distance between spray head and coated drum: 5cm
Number of coatings: Select an appropriate value between 2-4 times Curing temperature: 170 ° C. for 30 minutes (cleaning blade production example 1)
Thickness of 1.5 mm, 2 mm, 3 mm, 4 mm, JIS-A hardness of 57 as a cleaning blade of a process cartridge (cleaning blade is fixed) mounted on an image forming apparatus (manufactured by Imagio MF2200 manufactured by Ricoh) prepared as an evaluation machine Urethane rubber with a support at 60 °, 62 °, 77 °, 85 °, and 88 ° (made by Hokushin Kogyo) was prepared.

  Porous paper (grease paper) that absorbs the lubricating paint is sandwiched between the surfaces of these cleaning blades facing the photoreceptor so that the lubricating paint does not enter the edge of the blade. It restrained and it stood in the coating device using the jig | tool.

On the other hand, the side face of the blade was left with a width of 5 mm from the edge, and a sealing tape was applied to prevent the lubricating paint from adhering. After completion of such preparation, thermosetting type lubricating paint (Daiel Latex GLS-213F (A liquid): manufactured by Daikin Industries, Ltd.) and 20 parts by weight of Daiel Latex GL-200 (B liquid): Daikin Industries Using a spray gun (PIECECOM WIDE 308: manufactured by Olympos), a mixture containing 1 part by weight of the company was spray coated in a draft chamber in an environment of 23 to 25 (° C.). The film thickness change of the coating film was carried out by the opening amount of the spray gun and the number of application (2 to 5 times). After drying at 35 ° C. for about 10 hours, the sealing tape was peeled off, and further heated and cured at 130 ° C. for 30 minutes to be completely dried to prepare a cleaning blade sample. After forming the lubricating paint, the edge of the cleaning blade was confirmed with an optical microscope (manufactured by Olympus). The width from the blade edge to the lubricating paint thin film (corresponding to the width indicated by L2 in FIG. 3). It was 0.1 to 0.4 (mm).
In addition, the sample for friction coefficient measurement evaluated by the sample apply | coated to the 2 mm thickness urethane rubber (35 mm x 90 mm) prepared separately. The evaluation method was carried out by a measuring method based on the Euler belt method with a sample wound around a 30 mm drum and restrained with a tape.

Table 1 shows the contents of the samples thus obtained.
The surface roughness of the surface of the lubricating paint thin film was measured at a substantially central portion 2 mm above the blade edge on the side in contact with the photoreceptor.

(Examples 1-5)
As an image forming apparatus for evaluation, IMAGIO MF2200 (manufactured by Ricoh, contact charging type, process cartridge type) and a photoconductor 1-2 as a photoconductor were prepared. The cleaning blades of the process cartridge include B-1 (Example 1), B-2 (Example 2), B-3 (Example 3), B-5 (Example 4) and B shown in Table 1. -7 (Example 5) and B-10 (Example 6) were prepared.

  Before mounting the photoconductor on the process cartridge, lightly rub the entire surface of the photoconductor with a non-woven fabric (Hize Gauze, manufactured by Asahi Kasei) with fluororesin particles (L-2, manufactured by Daikin Industries). The coefficient was lowered to about 0.2 to 0.3.

  Next, blade sample B-1 shown in Table 1 was attached to the process cartridge. After mounting the process cartridge on the evaluation machine, the charging potential was set to about -800V, and the image portion potential was set to -120V. For the development, spherical toner (manufactured by Ricoh) having an average particle diameter of 6.8 μm, an average circularity of 0.978 and a wax content of 5% prepared by suspension polymerization is used, and A4 size paper is used. The sample was run through 20,000 sheets, and the image quality (mainly resolution and background stain), the appearance of the photosensitive layer, and the wear amount of the photosensitive layer were measured.

  The results are shown in Table 2.

  By applying a lubricant to the surface of the photoconductor in the initial stage, there is no abnormality in driving the photoconductor, and the photoconductor generates noise due to the effect of the low friction coefficient of the lubricating paint applied to the side of the cleaning blade. It rotated normally without emitting.

When 1.5 mm thick urethane rubber was used for the cleaning blade, the effect of the wall thickness appeared a little, and a slight background stain was observed, and the amount of wear tended to increase. Since it is not possible to increase the film thickness of the lubricating paint, it seems that it can be improved by shortening the free length by about 2 mm. It can be seen that the mechanical strength is insufficient.
In the other Examples 2 to 6, no cleaning failure that affected the image quality occurred, and high-resolution image quality was obtained. However, when a sample of B-10 having a slightly large surface roughness was used, background stains that seemed to have a little insufficient frictional resistance were slightly observed, but were within the practical range. It can be improved by reducing the surface roughness.

  When a blade having a wall thickness of 2.0 mm and a hardness of 85 ° was used, the photoconductor was rubbed and scratched. However, the toner was sufficiently prevented from entering and no cleaning failure occurred.

In Table 2, in the evaluation results for 20,000 sheets, ◎ indicates that the cleaning property, image quality, and photoreceptor appearance characteristics are good, ○ indicates that the cleaning property and image quality are within practical ranges, the photoreceptor appearance is good, and △ indicates cleaning. And image quality are almost within the practical range, and there is a slight problem with the external appearance characteristics of the photoconductor (problems may occur continuously, but improvements can be made)
Within the practical range, there is no problem in general use, but when the image quality is seen in detail, a point-like toner can be seen.
(Examples 7 to 12)
Photosensitive member 2-1 for evaluation of the cleaning blade, B-2 (Example 7), B-3 (Example 8), B-6 (Example 9), B-8 (Example 10) for the cleaning blade. , B-9 (Example 11) and B-11 (Example 12) were evaluated under the same conditions as in Examples 1-6. The results are shown in Table 3.

  By replacing the photoconductor with improved wear resistance, the wear of the photosensitive layer was reduced to about half, and the durability was doubled. However, with respect to the toner sample, the blade sample B-9, which maintains a good state and has a particularly large surface roughness, has a large surface roughness Rz of 3.8 μm and Rmax of 5.6 μm. This is presumably because the frictional resistance could not be lowered sufficiently, and the problem caused by the fact that the film thickness of the lubricating paint was a little thick appeared as a decrease in image quality (background stain). The determination is Δ, but improvement is possible by reducing the surface roughness. The reduction in resolution is due to the result of scratches on the photoreceptor, and the resolution of 6.3 lines / mm is at a level that causes no problem in practical use. Regarding sample B-11, it is considered that the strength of the blade is slightly insufficient. It can be improved by increasing the contact pressure.

The symbols ◎, ○, and Δ in Table 3 are the same as those described in Table 2.
(Comparative Examples 1-2)
Use the above-mentioned photoreceptor 1-2, photoreceptor 2-1 for the photoreceptor, and genuine parts of Imagio MF2200 (manufactured by Ricoh) for the cleaning blade (no lubrication paint applied, 2 mm thickness, contact pressure 23 g / cm), A lubricant (PTFE, L-2 / manufactured by Daikin Industries) was applied to the photoreceptor only in the initial stage, and the cleaning blade was evaluated in the same manner as in Examples 1-12. The results are shown in Table 4.

  In the cleaning blade used for the evaluation, the effect of applying the initial lubricant appeared on the first and second sheets, and it was possible to clean the substantially spherical toner. It was. This is because the frictional resistance between the photoconductor and the cleaning blade was small only in the initial stage due to the effect of the lubricant, so there was no distortion or stick-slip phenomenon on the blade edge, but the lubricant film was removed with the blade or developer. If it disappears, the effect of the lubricant is lost, and it is presumed that toner starts to come off.

In addition, x in the table indicates that there is no practicality at all.
(Comparative Examples 3-6)
(Production example 2 of cleaning blade)
Thickness of 2 mm and 3 mm, JIS-A hardness of 57 °, 62 °, 85 as a cleaning blade of a process cartridge (cleaning blade is fixed) mounted on an image forming apparatus (manufactured by Imagio MF2200 manufactured by Ricoh) prepared as an evaluation machine A urethane rubber with a support at 0 ° (made by Hokushin Kogyo) was prepared.

  Porous paper (grease paper) that absorbs the lubricating paint is sandwiched between the surfaces of these cleaning blades facing the photoreceptor so that the lubricating paint does not enter the edge of the blade. It restrained and stood in the coating device using the jig.

On the other hand, the side face of the blade was left with a width of 4 mm from the edge, and a sealing tape was applied to prevent the lubricant paint from adhering. After such a preparation is completed, a fluororesin (PFA MICROPOWDER MPE-056: made by Mitsui / DuPont Fluoro Chemical Co., Ltd.) is applied to a one-component room-temperature curing type paint (Daiel Latex GLP-102NR: made by Daikin Industries). Mixing was carried out for 20 minutes by a high-speed liquid collision dispersion method (Ultimizer, manufactured by Suginoma Machine Co., Ltd.). When applying using this lubricating paint, it is diluted with 1-butanol and slowly stirred with a stirrer, and sprayed in a 23-25 ° C. draft chamber using a spray gun (PIECECOM WIDE 308: manufactured by Olympus). Coating was performed. The film thickness of the coating film was adjusted so that the film thickness was between 50 and 80 (μm) by adjusting the opening amount of the spray gun and the number of coatings. After the lubricating paint was applied and left for 2 hours, the sealing tape was peeled off, and further placed in a thermostat at about 30 to 35 ° C. and dried for 25 hours to complete curing, thereby preparing a sample of a cleaning blade. After forming the lubricating paint, the edge of the cleaning blade was confirmed with an optical microscope (manufactured by Olympus). The width from the blade edge to the lubricating paint thin film (the width indicated by L2 in FIG. 3) was 0.3 to It was 0.9 mm.
In addition, the sample for friction coefficient measurement evaluated by the sample apply | coated to the 2 mm thickness urethane rubber (35 mm x 90 mm) prepared separately. The evaluation method was carried out by a measuring method based on the Euler belt method with a sample wound around a 30 mm drum and restrained with a tape.
Table 5 shows the contents of the sample thus obtained.

The friction coefficient of the thin film of the lubricating paint applied to the cleaning blade was approximately between 0.25 and 0.38 (according to the Euler belt method).
The surface roughness of the surface of the lubricating paint thin film was measured at a substantially central portion 2 mm above the blade edge on the side in contact with the photoreceptor.

  A photoconductor 1-2 was prepared as a photoconductor, and the photoconductor was mounted on a process cartridge of an evaluation machine (IMAGIO MF2200, manufactured by Ricoh), and then a cleaning blade and a charging roller were set in this order. In the developing part, spherical toner (toner concentration: 5% by weight) having an average particle diameter of 6.8 μm prepared by the same suspension polymerization method as in Examples 1 to 12 was charged. The image forming conditions were the same as those in Examples 1 to 12, and the cleaning blade was evaluated. The results are shown in Table 6.

  In the initial stage, the cleaning properties were all good, but cleaning defects gradually occurred in a stripe pattern. The resolution is a result two or three sheets after the image quality starts to deteriorate.

When the cause of the cleaning failure was confirmed, adhesion of foreign matter was observed over almost the entire surface of the photoreceptor. On the other hand, since the thin film peeled off locally on the cleaning blade, it was speculated that the lubricating thin film peeled off and adhered to the photosensitive member, resulting in poor cleaning. Further, the peeling causes distortion and stick-slip phenomenon on the blade edge, which seems to have caused the cleaning failure.
Therefore, the one-component paint of room temperature curing type is insufficient in terms of durability.

It is a figure which shows an example of the cleaning blade by this invention, (A) shows the whole structure, (B) has shown the contact state with the surface where a foreign material remains. 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 which shows another example of the principal part structure of the cleaning blade by this invention. It is a figure which shows the effect | action of the cleaning blade by this invention. It is a diagram which shows an example of the surface roughness of the lubricous coating material used for the cleaning blade by this invention. It is a diagram which shows the other example of the surface roughness of the lubricous coating material used for 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 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. It is a figure which shows another example of the image forming apparatus shown in FIG. It is a figure which shows the structure of the outward path cartridge used for the image forming apparatus shown in FIG. It is a figure which shows another example of the process cartridge shown in FIG. It is a figure which shows the structure of the photoconductor which is a latent image carrier used for FIG. 10 or FIG. FIG. 14 is a diagram showing another configuration of a photoreceptor that is a latent image carrier used in FIG. 10 or FIG. 13. FIG. 14 is a diagram showing still another configuration of a photoreceptor that is a latent image carrier used in FIG. 10 or FIG. 13. 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. 22 is a diagram for explaining a problem during cleaning of the residual toner illustrated in FIG. 21. It is a figure which shows the behavior of the spherical toner equivalent to a foreign material. FIG. 24 is a diagram for explaining a problem during cleaning of the spherical toner illustrated in FIG. 23.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 71 Cleaning blade 71a Support body 71d Blade 71f Edge 71e Lubricious paint

Claims (20)

A cleaning blade for cleaning foreign matter including residual powder,
The cleaning blade includes a blade body whose edge portion can be pressed against a surface on which the foreign matter remains, and a lubricating layer provided on a surface of the blade body surface opposite to the surface on which the foreign matter remains. With
The cleaning blade according to claim 1, wherein the blade main body is set in a pressure contact state in which the edge portion and the lubricating layer are simultaneously pressed against the surface on which the foreign matter remains. The cleaning blade according to claim 1, wherein
The blade main body is a flexible member, and the lubricating layer is provided in a range excluding at least the edge portion of the blade main body. The cleaning blade according to claim 1 or 2,
The cleaning blade according to claim 1, wherein the lubricating layer is provided in a range excluding an edge portion of the blade body and an end surface continuous therewith. The cleaning blade according to any one of claims 1 to 3,
The cleaning blade according to claim 1, wherein an end surface of the blade body is opposed to an upstream side in the moving direction of the surface on which the foreign matter remains, and at least an edge portion is pressed against the surface on which the foreign matter remains. The cleaning blade according to any one of claims 1 to 4,
The lubrication layer is applied from a position where it can contact the surface where the foreign matter remains together with the edge portion of the blade main body and the vicinity thereof according to the contact angle of the blade body with respect to the surface where the foreign matter remains. Characteristic cleaning blade. The cleaning blade according to any one of claims 1 to 5,
The thickness of the lubricating layer is set to a thickness at which the edge portion of the blade body and the lubricating layer can be simultaneously contacted according to the contact angle of the blade body with the surface on which the foreign matter remains. And a cleaning blade. The cleaning blade according to any one of claims 1 to 6, wherein the blade body is made of a material having a JIS-A hardness of 60 to 80 degrees. The cleaning blade according to claim 1,
The blade body has a thickness set to 1.5 to 3 mm. The cleaning blade according to claim 1,
The cleaning blade according to claim 1, wherein the blade body is in pressure contact with the surface on which the foreign matter remains with a contact pressure of 15 to 35 g / cm. The cleaning blade according to any one of claims 1 to 6,
The cleaning blade is configured by applying a material having chemical affinity to the blade body. The cleaning blade according to claim 10, wherein
A cleaning blade, wherein a thermosetting paint containing a fluororesin is used for the lubricating layer when the blade body uses urethane rubber. The cleaning blade according to claim 10 or 11,
The lubricating blade has a surface roughness of 3 μm or less and a maximum height Rmax of 5 μm or less at a 10-point average roughness (Rz). The cleaning blade according to any one of claims 10 to 12,
A thickness of the lubricating layer is set to 20 to 100 μm.   A cleaning device using the cleaning blade according to claim 1. The cleaning device according to claim 14, wherein
The cleaning device is equipped with a cartridge having a recovery mechanism for foreign matter removed from a surface on which foreign matter remains.   16. A process cartridge comprising the cleaning device according to claim 14 and a photosensitive member integrally, and detachable from a main body of the image forming apparatus. An image forming apparatus using the cleaning device according to claim 14. The image forming apparatus according to claim 17.
The surface on which the foreign matter remains is a latent image carrier capable of carrying a toner image to be transferred, and the latent image carrier is configured such that foreign matter is collected by the cleaning device after the toner image is transferred. An image forming apparatus. The image forming apparatus according to claim 18.
An image forming apparatus comprising: a single latent image carrier or a plurality of latent image carriers, wherein the latent image carrier is selected and installed according to an image forming mode. The image forming apparatus according to claim 18 or 19,
An image forming apparatus characterized in that when a plurality of latent image carriers are provided, an image formed by each latent image carrier can be sequentially transferred onto an intermediate transfer member or a recording medium.

Images