JP2010048934A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the occurrence of problems caused such that, in the case a brush member is rotated to apply a lubricant onto an image carrier, a lot of lubricant scatters into the apparatus without being applied to the image carrier, and further, when the amount of the lubricant applied onto the image carrier is small, lubricity and protectability can not be obtained, thereby a cleaning failure and the problem of deterioration of the image carrier due to discharge are caused. <P>SOLUTION: A lubricant application auxiliary member 5 is provided in the vicinity of the outlet side of a nip part in the rotary direction of the bush, of the contact nip part to the image carrier 1, of the brush member 3, and arranged so that one end side of the lubricant application auxiliary member is brought into contact with the brush member, and the other edge side is made close to the image carrier. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a facsimile, a printer, a plotter, and a multi-function machine that includes a lubricant application device that applies a lubricant to an image carrier.

  Electrophotographic image formation uses a photoconductive phenomenon to form an electrostatic charge image (electrostatic latent image) on an image carrier, and charged electrostatic particles (toner) colored on the electrostatic latent image. This is performed by a process of attaching a film with an electrostatic force to form a visible image.

  In such an electrophotographic image forming apparatus, various kinds of waxes, fluororesins (polytetrafluoroethylene, polyvinylidene fluoride, etc.) and higher fatty acid metal salts (zinc stearate) are used on the image bearing member and intermediate transfer belt, which are the main components. Etc.) as a lubricant. This lubricant application technique is used to eliminate problems that occur in the electrophotographic cleaning process, i.e., the process of scraping the toner and impurities remaining on the image carrier and intermediate transfer belt with a cleaning brush or cleaning blade. It is.

  The above problem due to the application of the lubricant is solved by improving the cleaning property for removing the toner from the surface of the image carrier. By applying the lubricant to the surface of the image carrier, the coefficient of friction on the surface of the image carrier is reduced, and deposits attached to the surface of the image carrier can be easily removed. That is, it is possible to easily remove the toner that cannot be transferred onto the final recording material such as paper and remains on the image carrier or the intermediate transfer belt.

  In recent years, spherical toners prepared by a polymerization method have begun to be used, but these have a uniform particle size distribution and can effectively reduce the particle size. On the other hand, there is also a problem that cleaning from the image carrier becomes difficult. From such a technical background, it is considered that the improvement of the cleaning property by using the lubricant will become a more important technology in the future.

  Further, as a method for solving the above-mentioned problems by applying lubricant, prevention of oxidative deterioration due to discharge on the surface of the image carrier can be mentioned. In order to form an electrostatic charge image (electrostatic latent image) on the image carrier, it is necessary to uniformly charge the surface of the image carrier by charging means. As a specific charging means, in recent years, there is a means for applying a high voltage to the charging roller member to directly discharge the image bearing member for charging.

  However, the method of directly discharging and charging the image carrier causes a problem that the surface of the image carrier is deteriorated. In particular, in a so-called non-contact charging roller system in which the charging roller member is not brought into contact with the image carrier, it is necessary to apply an AC voltage to the roller member, and it has been found that the surface of the image carrier is likely to deteriorate. It has been clarified that the deteriorated surface of the image bearing member is easily worn by mechanical rubbing with a cleaning brush or a cleaning blade which is a cleaning member.

  Therefore, the technique of applying a lubricant to the surface of the image carrier is an important technique for reducing damage to the image carrier due to electric discharge.

  In general, these lubricants are supplied to the surface of the image carrier in a small amount in the form of powder. As a specific method thereof, a lubricant solidly formed in a block shape is used, such as a brush. The powder is scraped off by an application means to form powder, and a powdery lubricant held by a brush is applied in contact with the image carrier.

  Lubricant application by the brush member is applied by rotating the brush member, so it is difficult to apply all of the solid molded lubricant to the image carrier, and many lubricants are not applied to the image carrier. Scatters into the apparatus and contaminates the image forming apparatus. Further, if the amount of lubricant applied to the image carrier is small, lubricity and protection cannot be obtained, which causes problems such as poor cleaning and deterioration due to discharge of the image carrier.

(1): In order to solve these problems, there is an example in which a scattering prevention member is provided on the downstream side of the supply means for supplying the lubricant (see, for example, paragraph 0024 of FIG. 4 and FIG. 4). Lubricant supply means scrapes the solid lubricant with a rotating brush into small particles and supplies them to a belt-like intermediate transfer body, but since the lubricant is small particles, it adheres to the intermediate transfer body. Missing lubricant particles will be scattered. Therefore, by providing a lubricant scattering prevention member on the downstream side of the supply means, it is possible to prevent diffusion inside the image forming apparatus. However, in such a configuration in which the periphery of the brush is opened in the section from the supply means to the scattering prevention member, the lubricant is scattered in the cleaning unit in the section by the rotation of the brush. There is no effect of increasing the efficiency and the consumption of the lubricant does not decrease. As described in Japanese Patent Application Laid-Open No. H10-228867, the scattering prevention member provided on the downstream side of the supply means (on the nip portion entrance side with respect to the intermediate transfer member) at the position away from the brush member (supply member) in the rotation direction of the brush performs cleaning. Scattering into the apparatus cannot be prevented and is not effectively applied to the image carrier. According to the configuration shown in FIG. 4 of Patent Document 1, a plate-like member that seals the cleaning means is placed close to the brush on the exit side of the nip portion with the intermediate transfer member in the rotation direction of the brush. However, since the base end of the plate-shaped member is inclined in a direction away from the surface of the intermediate transfer member, it passes through the nip portion along with the rotation of the brush without being applied and comes out from the exit side of the nip portion. There is a possibility that the lubricant particles to be scattered are scattered outside the cleaning means.

(2): a lubricant supply device for supplying a lubricant to the surface of the image carrier, and a lubricant carrier means (brush member) that faces the image carrier in a non-contact manner and carries the lubricant; Some have transition means (power supply, electrode) for transferring the lubricant carried on the lubricant carrying means onto the image carrier (see, for example, Patent Document 2). In Patent Document 2, the brush member is not in contact with the image carrier and has no concept of a nip portion, which is different from the method of the present invention in which the brush is brought into contact with the image carrier. There is no disclosure of a mechanical means for preventing the lubricant released and flying from the brush member from being scattered into the cleaning device and leading it to the image carrier.

JP 2003-29550 A JP 2007-310336 A

  An object of the present invention is to provide means for preventing scattering of a lubricant and increasing the efficiency with which a powdery lubricant adheres to an image carrier.

  As a result of investigation by the present inventor in order to clarify the lubricant application mechanism by the brush member, the position where the lubricant is applied to the image carrier is the outlet side of the nip portion of the brush member, and the rotational nip portion of the brush member It was found that the lubricant flew and applied on the outlet side. In other words, when the brush member rotates, the solid lubricant is mechanically scraped off, held in the brush member as a powder lubricant, and when the powder lubricant is applied in contact with the image carrier, the image carrier The powdered lubricant flies and is applied to the image carrier by the repulsive force that restores the brush member deformed at the nip with the body to the original state on the exit side.

The present invention provides an image carrier that carries a toner image and moves on the surface thereof, a charging device that charges the image carrier, in order to prevent scattering of the lubricant and increase the efficiency with which the powdery lubricant adheres to the image carrier. A latent image forming unit that forms an electrostatic latent image on a charged image carrier, a developing device that visualizes the electrostatic latent image as a toner image, a transfer device that transfers the toner image to a transfer material, and an image Lubricating in an image forming apparatus having a cleaning device for removing unnecessary toner adhering to the surface of a carrier, and a lubricant applying device having a solid lubricant and a rotating brush member for applying the solid lubricant to an image carrier Proposed to arrange the agent application device upstream of the image bearing member rotation direction with respect to the cleaning device, and to arrange the lubricant application auxiliary member near the exit side of the nip portion in the brush rotation direction of the contact nip portion between the image carrier and the brush member To do. The lubricant application auxiliary member prevents the flying powdery lubricant from contaminating the inside of the cleaning device. Further, since the powdery lubricant that scatters is eliminated, the efficiency of supplying the lubricant to the image carrier increases, and the application of the lubricant to the image carrier is made effective.
In order to achieve the above object, an invention according to claim 1 is directed to an image carrier that carries a toner image and moves on the surface, a charging device that charges the image carrier, and an electrostatic latent image on the charged image carrier. A latent image forming means for forming an image; a developing device that visualizes the electrostatic latent image on the image carrier as a toner image; and a transfer device that transfers the toner image on the image carrier to a transfer material; An image having a cleaning device for removing unnecessary toner adhering to the surface of the image carrier, and a lubricant application device having a solid lubricant and a rotating brush member for applying the solid lubricant to the image carrier In the forming apparatus, the lubricant application device is disposed upstream of the cleaning device in the rotation direction of the image carrier, and the contact nip portion between the image carrier and the brush member is near the exit side of the nip portion in the brush rotation direction. Lubricant application The auxiliary member is provided, one end side of the lubricant applying auxiliary member into contact with the brush member, the other end was arranged adjacent to the image bearing member.
According to a second aspect of the present invention, there is provided an image carrier that carries a toner image and moves on the surface, a charging device that charges the image carrier, and a latent image that forms an electrostatic latent image on the charged image carrier. Forming means, a developing device that visualizes the electrostatic latent image on the image carrier as a toner image, a transfer device that transfers the toner image on the image carrier to a transfer material, and a surface of the image carrier. In the image forming apparatus comprising: a cleaning device that removes adhering unnecessary toner; and a lubricant application device that includes a solid lubricant and a rotating brush member for applying the solid lubricant to the image carrier. The lubricant applicator is disposed upstream of the image carrier in the rotation direction of the image carrier, and the brush member is rotated near the exit side of the nip portion in the brush rotation direction of the contact nip between the image carrier and the brush member. Along with Provided lubricant applying auxiliary member for guiding the surface of the image bearing member side dammed lubricant particles to be moved to the nip outer side.
According to a third aspect of the present invention, there is provided an image carrier that carries a toner image and moves on the surface, a charging device that charges the image carrier, and a latent image that forms an electrostatic latent image on the charged image carrier. Forming means, a developing device that visualizes the electrostatic latent image on the image carrier as a toner image, a transfer device that transfers the toner image on the image carrier to a transfer material, and a surface of the image carrier. In the image forming apparatus comprising: a cleaning device that removes adhering unnecessary toner; and a lubricant application device that includes a solid lubricant and a rotating brush member for applying the solid lubricant to the image carrier. The lubricant application device is disposed upstream of the image carrier in the rotation direction of the image carrier, and a lubricant application auxiliary member is provided near the exit side of the nip portion in the brush rotation direction of the contact nip portion between the image carrier and the brush member. Provide this Lubricant particles which are arranged so that one end side of the lubricant application assisting member is in contact with the brush member and the other end side is close to the image carrier, and moves to the outside of the nip portion as the brush member rotates. Was blocked and led to the surface side of the image carrier.
According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects, the lubricant application auxiliary member is a strip-shaped member that contacts the brush member, and the brush member includes It has the function of removing the attached deposits.
According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to fourth aspects, the solid lubricant is zinc stearate.
According to a sixth aspect of the present invention, in the image forming apparatus according to any one of the first to fifth aspects, a protective layer using a binder resin having a crosslinked structure is provided on a surface layer of the image carrier, It was decided to have a charge transport material in the structure of the binder resin.
The image carrier, the charging device, the developing device, the cleaning device, and the lubricant applying device according to claim 1, wherein at least the image carrier, the cleaning device, and the lubricant applying device are included. The process cartridge is integrally connected to be detachable from the main body of the image forming apparatus.

  According to the present invention, it is possible to provide means for preventing the scattering of the lubricant and increasing the efficiency with which the powdery lubricant adheres to the image carrier.

1. [Comparative example]
As a premise of the present invention, an image forming apparatus having no lubricant application auxiliary member will be described as a comparative example.

(Configuration of image forming apparatus):
FIG. 7 shows a configuration of a conventional image forming apparatus for applying a lubricant as a comparative example. In FIG. 7, a conventional image forming apparatus includes a photosensitive drum 1 as an image carrier that rotates and moves in the direction of arrow A in the drawing. As the photosensitive drum 1, a photosensitive layer made of an organic photosensitive member is formed on the outer peripheral surface of an aluminum substrate, and the drum surface layer is made of polycarbonate.

  Around the photosensitive drum 1, there are a charging device 7 as a charging means for charging the photosensitive drum 1, and an exposure device 8 as a latent image forming means for forming an electrostatic latent image on the charged photosensitive drum 1. And a developing device 9 as developing means for visualizing the electrostatic latent image on the photosensitive drum 1 as a toner image, and a transfer for transferring the toner image on the photosensitive drum 1 to a recording material made of a sheet-like medium. A transfer device 10 as a means, a cleaning device 11 as a cleaning means for removing unnecessary toner adhering to the surface of the photosensitive drum 1, and a static eliminating device 12 as a means for removing residual charges on the surface of the photosensitive drum 1 are arranged. Yes. Further, on the recording material P on the downstream side of the recording material conveyance direction (in the direction of arrow E in the figure) in which the recording material P such as paper is conveyed with respect to the transfer region 60 where transfer is performed by the transfer device 10. A fixing device (not shown) is provided as a fixing unit for fixing the toner image.

  As a lubricant application device for applying a lubricant to the photosensitive drum 1, a fixed lubricant 2, a brush member 3, a flicker 4 for removing deposits attached to the brush member 3, and the like as one unit, a photosensitive drum 1 is disposed upstream of the cleaning device 11.

  The charging device 7 uniformly charges the surface of the photosensitive drum 1. The charging device 7 is arranged such that a charging member is brought into contact with the surface of the photosensitive drum 1 or a small gap is provided from the surface of the photosensitive drum 1 and a charging bias is applied to the charging member 7 to thereby surface the surface of the photosensitive drum 1. Are uniformly charged to a desired polarity and a desired potential. As this charging member, for example, a charging roller made of an elastic body, a scorotron charger using a wire electrode and a grid electrode, or the like can be used.

  The exposure device 8 forms an electrostatic latent image corresponding to image data on the surface of the photosensitive drum 1 charged by the charging device 7. The exposure apparatus 8 uses, for example, an LD (Laser Diode) or an LED (Light Emitting Diode) as a light emitting element, and irradiates light based on image data onto a uniformly charged surface of the photosensitive drum 1. As a result, an electrostatic latent image is formed on the surface of the photosensitive drum 1. The exposure apparatus 8 is not limited to such a configuration, and a widely known apparatus can be used.

  The developing device 9 performs development by attaching toner to the electrostatic latent image formed on the surface of the photosensitive drum 1. The developing device 9 includes a developing roller 9a as a developer carrying member having a magnet roller as a magnetic field generating means arranged in a fixed manner. The developing roller 9 a rotates while carrying the developer on the surface thereof, thereby conveying the developer to a developing area facing the photosensitive drum 1. In this embodiment, a two-component developer composed of a toner and a carrier is used as a developer, and a magnetic brush developing system is used in which the carrier is sprinkled in the developing region by the magnetic force of a magnet roller and developed in a brush shape. .

  As the developer, a one-component developer composed only of toner may be used without using a carrier like the two-component developer. A developing bias is applied to the developing roller 9a from a developing bias power source. As a result, in the development area 90 constituted by the facing area between the photosensitive drum 1 and the developing roller 9a, there is a potential difference between the surface potential of the developing roller 90 and the potential of the electrostatic latent image portion on the surface of the photosensitive drum 1. The toner in the developer adheres to the electrostatic latent image due to the action of the developing electric field formed by this potential difference. As a result, the electrostatic latent image on the photosensitive drum 1 becomes a toner image. The developing device 9 is not limited to such a configuration, and a widely known device can be used.

  The transfer device 10 transfers the toner image on the photosensitive drum 1 onto the recording material P conveyed in the direction of arrow E in the figure. In the transfer device 10, a transfer member such as a transfer roller is brought into contact with the surface of the photosensitive drum 1 with a predetermined pressing force, and a transfer nip is formed in a transfer region 60 between the transfer member and the photosensitive drum 1.

  A toner image on the surface of the photosensitive drum 1 is formed by a transfer electric field formed by applying a transfer bias having a polarity opposite to that of the toner from a transfer bias power source to the transfer member while the recording material P is sandwiched between the transfer nips. Transfer onto the recording material P. As the transfer member, for example, a transfer roller or transfer belt made of an elastic body can be used. Further, it is possible to use an intermediate transfer belt that does not directly transfer to the recording material P but transfers a plurality of toner images to the recording material P after being superimposed. The recording material P onto which the toner image has been transferred in this manner is conveyed to the fixing device (not shown), where the toner image is fixed and then discharged outside the apparatus.

  The cleaning device 11 removes untransferred toner remaining on the surface of the photosensitive drum 1 without being transferred from the surface of the photosensitive drum 1. As the cleaning device 11, a cleaning blade member for scraping and removing the transfer residual toner on the surface of the photosensitive drum 1 is used.

  As the cleaning blade member, a polyurethane blade member attached to a metal support is used, and the contact method with the photosensitive drum 1 is to contact the arrow A indicating the rotation direction of the photosensitive drum 1 in the counter direction. Yes. As for the cleaning blade member, not only toner removal from the photosensitive drum 1 but also paper dust when using paper as the recording material P, discharge products and toner when the photosensitive drum 1 is charged by discharge by the charging device 7 are used. It also has a function of removing impurities such as additives added to the photosensitive drum 1.

  Further, it has a function of forming a powdery lubricant applied by the brush member 3 into a film. Since the lubricant applied by the brush member 3 is in a powder state, the lubricity on the photosensitive drum 1 is not sufficiently exhibited. This is because the lubricant needs to be formed into a film on the surface of the photosensitive drum 1 in order to exert the lubricant.

  The static eliminator 12 removes residual charges on the surface of the photosensitive drum 1. The surface of the photosensitive drum 1 from which the residual charge has been removed contributes to the next image formation. In addition, although this static elimination apparatus 7 employ | adopts the optical static elimination system using LED etc., it is not restricted to this.

  The brush member 3 is in the shape of a rotating roller and is installed in contact with the solid lubricant 2, and the solid lubricant 2 is scraped off by the rotation of the brush member 3. At this time, the powdered lubricant is adhered and held on the surface of the brush fiber bristles constituting the brush member 3. A spring member 61 is disposed on the opposite side of the solid lubricant 2 to the brush facing surface in order to eliminate uneven contact between the brush member 3 and the solid lubricant 2, and presses the solid lubricant 2 against the brush member 3. It has become.

  The brush member 3 is made of resin fibers such as nylon, rayon, acrylic, vinylon, polyester, and vinyl chloride. If necessary, conductive fibers obtained by mixing the aforementioned resin fibers with a conductivity-imparting agent such as carbon are used. May be. The brush member 3 is formed by placing a brush in which a bristle having a length in the range of 0.2 to 20 (mm), preferably 0.5 to 10 (mm), on a base cloth, on a base cloth made of metal. It is composed by wrapping.

  When the length of the bristle is 20 (mm) or more, the inclination angle in the reverse direction of the brush body decreases due to repeated rubbing with the solid lubricant 2 and the photosensitive drum 1 with the operation time of the brush member 3. The hair is scraped and the scraping property of the solid lubricant 2 and the coating property of the lubricant to the photosensitive drum 1 are lowered. When the length of the brush hair is 0.2 (mm) or less, the physical force on the solid lubricant 2 is insufficient. Therefore, it is preferable to set it in the range of 0.2 to 20 (mm), preferably 0.5 to 10 (mm).

The brush hair preferably has a brush density of 1 to 50 (10,000 / inch ² ) and a brush resistance of 10 ⁻² to 10 ¹² (Ω · cm). In this embodiment, the brush length is 3 (mm) and the brush density is 10 ( 10,000 / inch ² ) and a brush resistance of 10 ⁵ (Ω · cm) are used.

  The image forming apparatus of this example scrapes off the solid lubricant 2 and the solid lubricant 2 for applying the lubricant to the photosensitive drum 1 and applies the brush member 3 and the lubricant to the photosensitive drum 1. An auxiliary member 5 is provided.

  In this example, the brush member 3 rotates in the direction of arrow B, which is a different direction from the photosensitive drum 1. Accordingly, the application direction is forward application. Accordingly, the lubricant application assisting member 5 is disposed on the upstream side of the cleaning device 11 (on the nip portion exit side of the brush member 3 with respect to the photosensitive drum 1) in the rotation direction of the photosensitive drum 1.

(Mechanism of applying lubricant to photosensitive drum):
A mechanism for applying a powdery lubricant from the brush member 3 to the photosensitive drum 1 will be described. In FIG. 8, which shows an enlarged arrangement of the solid lubricant 2, the brush member 3, and the photosensitive drum 1, the brush member 3 is in contact with the photosensitive drum 1 at a constant interval (biting amount). A nip is formed between the body drum 1 and the brush member 3.

  In this nip portion, the brush bristles of the brush member 3 fall down in a direction different from the arrow B indicating the rotation direction of the brush member 3. Since the brush member 3 that has fallen in the nip portion is rotated by the brush member 3, the brush hair is eventually released on the nip portion outlet side, and the brush hair tries to return to the original state. At this time, the bristle moves violently in the direction of arrow C (brush rotation direction) by the repulsive force due to the restoring force. The powdery lubricant held on the brush member 3 by the movement due to the repulsive force leaves the brush member 3 and flies to be applied to the photosensitive drum 1.

  As described above, the powdery lubricant flies and adheres to the photosensitive drum 1 on the exit side of the nip portion of the brush member 3 with the photosensitive drum 1, but the scraping force of the solid lubricant 2 by the brush member 3 is increased. When the amount of powdery lubricant held in the brush member 3 increases and the brush hair falls too much at the nip portion between the brush member 3 and the photosensitive drum 1, the repulsive force increases. Sometimes the amount of lubricant to fly increases.

  FIG. 9 shows a state in which the amount of powdery lubricant retained in the brush member 3 increases, and more lubricant than necessary flies and scatters. When the lubricant scatters in this way, some of the lubricant does not adhere to the photosensitive drum 1, and the amount of solid lubricant necessary to apply to the photosensitive drum 1 is insufficient, or other members are soiled. A malfunction will occur.

2. [Example of the present invention]
An image forming apparatus provided with a lubricant application device having a lubricant application auxiliary member will be described.

(Configuration of image forming apparatus):
FIG. 1 shows a schematic configuration of an image forming apparatus according to the present invention. As a lubricant application device for applying a lubricant to a photosensitive drum 1, a solid lubricant 2, a spring member 61, and a brush member 3 are shown. The lubricant application assisting member 5, a case covering the lubricant application auxiliary member 5, and the like are arranged as a single unit on the upstream side of the cleaning device 11 in the rotational direction of the photosensitive drum 1. The difference from the comparative example described in FIG. 7 is that the flicker 4 shown in FIG. 7 is not provided, and the lubricant application auxiliary member 5 is provided. Other configurations are the same as those described with reference to FIG. The mechanism for applying the lubricant to the photosensitive drum is basically the same as that described in the comparative example.

(Configuration of lubricant application auxiliary member) (corresponding to claims 1 to 3):
FIG. 2 is a feature of the present invention. Lubricant application is performed on the upstream side in the rotation direction of the photosensitive drum with respect to the cleaning device 11 and in the vicinity of the exit side of the nip portion in the brush rotation direction of the contact nip portion between the photosensitive drum 1 and the brush member 3. It is the Example figure which has arrange | positioned the auxiliary member 5. FIG. The lubricant application auxiliary member 5 is arranged so that one end side thereof is in contact with the brush member 3 and the other end side thereof is close to the circumferential surface of the photosensitive drum 1. The lubricant application assisting member 5 has a plate shape and is long in the axial direction of the brush member 3 and the photosensitive drum 1 (longitudinal direction: a direction penetrating the paper surface of FIG. 2). It is arranged with substantially the same length along.

  The lubricant application assisting member 5 dams up the lubricant particles that are going to move outwardly with the rotation of the brush member 3, guides it to the surface side (circumferential surface side) of the photosensitive drum 1, and applies it.

  Thus, the lubricant application assisting member 5 can confine that the lubricant more than necessary flies and scatters, and the lubricant application assisting member 5 can sensitize the lubricant application assisting member 5 even if the lubricant more than necessary flies and scatters. It becomes attached to the body drum 1 and the application efficiency of the lubricant is greatly improved, and contamination by the lubricant in the apparatus can be prevented.

  As described above, the lubricant application assisting prevention member 5 has a configuration in which one end side thereof is in contact with the brush member 3. FIG. 3 shows an enlarged contact portion between the lubricant application auxiliary member 5 and the brush member 3. In the comparative example, as described in the explanation with reference to FIG. 1, in the conventional lubricant application device, a means such as flicker 4 is brought into contact with the brush member 3 in order to remove the deposits attached to the brush member 3. In this configuration, deposits are removed. In this case, the number of parts increases, and there are cases where the cost is increased and the space is required to be secured. In this regard, in the present invention, one end side of the lubricant application auxiliary member 5 is brought into contact with the brush member 3 in order to give the lubricant application auxiliary member 5 a flicker function.

  In FIG. 3, when the lubricant application assisting member 5 comes into contact with the rotating brush member 3, the brush bristle falls in a direction different from the arrow B direction, and the restoring force of the brush bristle when separated from the lubricant application assisting member 5. Thus, the toner adhering to the brush member 3 and the powdered lubricant that could not be applied can be removed.

  As described above, in this example, scattering of the powdery lubricant is prevented. Further, the efficiency with which the powdery lubricant adheres to the photosensitive drum 1 is increased. That is, the solid lubricant 2 is mechanically scraped by the rotation of the brush member 3, is made into a powdery lubricant, is held on the brush member 3, and the powdery lubricant is brought into contact with the photosensitive drum 1 and applied. In this case, the powdered lubricant flies and is applied to the photosensitive drum 1 by the repulsive force that restores the brush member 3 deformed at the nip portion with the photosensitive drum 1 to the original state on the nip exit side. At this time, conventionally, a large amount of powdery lubricant that does not adhere to the photosensitive drum 1 is scattered and the inside of the image forming apparatus is contaminated. It is possible to prevent the internal lubricant from contaminating the inside of the apparatus. Further, since the amount of the powdery lubricant that scatters is reduced, the efficiency of supplying the lubricant to the image carrier increases. Further, when the blade member is used as the cleaning device by disposing the lubricant application device on the upstream side in the rotation direction of the image carrier of the cleaning device, molecules for expressing the lubricating function of the powder lubricant to the image carrier Film formation can be performed efficiently.

(Claim 4):
The lubricant application auxiliary member 5 has a strip shape (long plate shape). A rubber member or a resin member can be used. Alternatively, a thin metal plate may be used. If the brush member 3 has a strength that causes the brush member 3 to fall in a direction different from the rotation direction when it is bitten (pressed in) into contact with the brush member 3, it exerts a function of removing deposits attached to the brush member. So good.

  In this example, the brush member 3 rotates in contact with the photosensitive drum 1 in order to improve the polishing effect of the solid lubricant by the brush member. Therefore, the residual toner and impurities on the photosensitive drum 1 are removed from the brush member. 3 is held. Therefore, conventionally, the brush member is usually cleaned by bringing a removal member such as flicker for removing them into contact with the brush member. In the present invention, by using the lubricant scattering prevention member of claim 1 as a member for cleaning the brush member 3, the apparatus can be reduced in size and cost can be reduced.

(Claim 5):
As the solid lubricant 2 used in this example, a lubricant obtained by dissolving a lubricant additive mainly composed of zinc stearate, having no side effect due to overcoating and having sufficient lubricity is used.

  It is preferred to use a lamellar crystal powder such as zinc stearate. A lamellar crystal has a layered structure in which amphiphilic molecules are self-organized, and when a shearing force is applied, the crystal breaks along the layers and becomes slippery. This action leads to a lower coefficient of friction, and the characteristics of the lamella crystal that uniformly covers the surface of the photosensitive drum 1 by receiving a shearing force can effectively cover the surface of the photosensitive drum 1 with a small amount of lubricant. By this reduction in the coefficient of friction, the blade member as the cleaning device can exhibit its cleaning performance.

  In addition to zinc stearate, those having a stearic acid group such as barium stearate, iron stearate, nickel stearate, cobalt stearate, copper stearate, strontium stearate and calcium stearate can be used. . Also, the same fatty acid group zinc oleate, barium oleate, lead oleate, the same as stearic acid, zinc palmitate, barium palmitate, lead palmitate, the same as stearic acid may be used. . In addition, caprylic acid, linolenic acid, corinolenic acid and the like can be used as the fatty acid group. In addition, waxes such as candelilla wax, canrunauba wax, rice wax, wood wax, sesame oil, beeswax and lanolin can also be used. These are easy to use because they easily become organic solid lubricants and have good compatibility with the toner.

  Zinc stearate is a typical lamellar crystal powder. A lamellar crystal has a layered structure in which amphiphilic molecules are self-organized, and when a shearing force is applied, the crystal breaks along the layers and is slippery. This action is effective for lowering the coefficient of friction, and the characteristics of the lamellar crystal that uniformly covers the surface of the image carrier under shearing force can effectively cover the surface of the image carrier with a small amount of lubricant. The surface of the image bearing member was effectively covered with a small amount of lubricant, and the lubricity was exhibited.

(Claim 6):
The photosensitive drum 1 of the present invention will be described. A photosensitive drum 1 as an image carrier used in the present embodiment is a negatively charged organic photosensitive member, and a photosensitive layer or the like is provided on a drum-shaped conductive support.

  FIG. 4 is a cross-sectional view showing a part of the photosensitive drum 1 used in this embodiment. An undercoat layer 51 which is an insulating layer is provided on the conductive support 50 as a base layer. Further, a charge generation layer 52 and a charge transport layer 53 as a photosensitive layer are provided thereon. Furthermore, a surface protective layer 54 is laminated thereon.

The conductive support 50, can be used for indicating the volume resistivity 10 10 ^(Ω · cm) or less conductive. The photosensitive layer may be a single layer or a laminate, but for convenience of explanation, first, a case of a laminate configuration comprising a charge generation layer 52 and a charge transport layer 53 will be described. The charge generation layer 52 is a layer mainly composed of a charge generation material.

  A known charge generating material can be used for the charge generating layer 52, and representative examples thereof include monoazo pigments, disazo pigments, trisazo pigments, perylene pigments, perinone pigments, quinacridone pigments, and quinone condensed polycyclic compounds. , Squaric acid dyes, other phthalocyanine pigments, naphthalocyanine pigments, azulenium salt dyes, and the like, which are useful. These charge generation materials can be used alone or in combination.

  In the charge generation layer 52, a charge generation material is dispersed in a suitable solvent together with a binder resin as necessary using a ball mill, an attritor, a sand mill, an ultrasonic wave, or the like, and this is dispersed on a conductive support or undercoat. It is formed by applying on the layer and drying. As a coating method for the coating solution, a dip coating method, spray coating, beat coating, nozzle coating, spinner coating, ring coating, or the like can be used. The thickness of the charge generation layer 52 is suitably about 0.01 to 5 (μm), preferably 0.1 to 2 (μm).

  The charge transport layer 53 can be formed by dissolving or dispersing a charge transport material and a binder resin in an appropriate solvent, and applying and drying the solution on the charge generation layer. Further, if necessary, two or more kinds of plasticizers, leveling agents, antioxidants and the like can be added. The amount of the charge transport material is appropriately 20 to 300 parts by weight, preferably 40 to 150 parts by weight, based on 100 parts by weight of the binder resin. The thickness of the charge transport layer is preferably 25 (μm) or less from the viewpoint of resolution and responsiveness. Regarding the lower limit, although it differs depending on the system to be used (particularly charging potential, etc.), 5 (μm) or more is preferable.

  Next, the case where the photosensitive layer has a single layer structure will be described. The photosensitive layer is prepared by dissolving or dispersing the above-described charge generation material, charge transport material, binder resin, etc. in an appropriate solvent, and applying and drying the solution on the conductive support 50 or the undercoat layer 51. Can be formed. You may comprise from a charge generation material and binder resin, without containing a charge transport material. Moreover, a plasticizer, a leveling agent, antioxidant, etc. can also be added as needed.

  As the binder resin, in addition to the binder resin previously mentioned in the charge transport layer 53, the binder resin mentioned in the charge generation layer 52 may be mixed and used. Of course, the polymer charge transport materials mentioned above can also be used favorably. The amount of the charge generating material with respect to 100 parts by weight of the binder resin is preferably 5 to 40 parts by weight, the amount of the charge transporting material is preferably 0 to 190 parts by weight, and more preferably 50 to 150 parts by weight.

  The photosensitive layer is formed by dip coating, spray coating, bead coating, a coating solution in which a charge generating material and a binder resin are dispersed together with a charge transporting material using a solvent such as tetrahydrofuran, dioxane, dichloroethane, and cyclohexane. It can be formed by coating with a ring coat or the like. The film thickness of the photosensitive layer is suitably about 5 to 25 (μm).

  The undercoat layer 51 generally contains a resin as a main component. However, considering that the photosensitive layer is applied with a solvent on these resins, the undercoat layer 51 is a resin having a high solvent resistance with respect to a general organic solvent. Is desirable. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include a curable resin that forms a three-dimensional network structure such as a resin. A metal oxide fine powder pigment exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like may be added to the undercoat layer in order to prevent moire and reduce residual potential. Further, these undercoat layers can be formed using an appropriate solvent and coating method as in the above-described photosensitive layer.

Furthermore, the undercoat layer 51 of the present invention, a silane coupling agent, a titanium coupling agent, a chromium coupling agent and the like can also be used. In addition, in the undercoat layer of the present invention, Al ₂ O ₃ is provided by anodic oxidation, organic substances such as polyparaxylylene (parylene), SiO ₂ , SnO ₂ , TiO ₂ , ITO, CeO ₂ A material provided with an inorganic material such as a vacuum thin film can also be used favorably. In addition, known ones can be used. The thickness of the undercoat layer is suitably from 0 to 5 (μm).

  In the present invention, the outermost surface layer has a protective layer 54 in order to prevent mechanical wear. As the binder structure of the protective layer 54, the protective layer 54 having a crosslinked structure is also effectively used. Regarding the formation of a cross-linked structure, a reactive monomer having a plurality of cross-linkable functional groups in one molecule is used to cause a cross-linking reaction using light or thermal energy to form a three-dimensional network structure. is there. This network structure functions as a binder resin and exhibits high wear resistance.

  From the viewpoint of electrical stability, printing durability, and life, it is a very effective means to use a monomer having a charge transporting ability in whole or in part as the reactive monomer. By using such a monomer, a charge transport site is formed in the network structure, and the function as the protective layer 54 can be sufficiently expressed.

  The reactive monomer having charge transporting ability includes a compound containing at least one charge transporting component and a silicon atom having a hydrolyzable substituent in the same molecule, and a charge transporting component in the same molecule. A compound containing a hydroxyl group, a compound containing a charge transporting component and a carboxyl group in the same molecule, a compound containing a charge transporting component and an epoxy group in the same molecule, a charge transporting component in the same molecule And a compound containing an isocyanate group. These charge transport materials having a reactive group may be used alone or in combination of two or more.

  More preferably, a reactive monomer having a triarylamine structure is effectively used as the monomer having a charge transporting ability because of high electrical and chemical stability and high carrier mobility.

  In addition to this, monofunctional and bifunctional polymerizable monomers and polymerizable oligomers are used in combination for the purpose of imparting functions such as viscosity adjustment during coating, stress relaxation of the cross-linked charge transport layer, low surface energy and friction coefficient reduction. be able to. As these polymerizable monomers and oligomers, known ones can be used.

  In the present invention, the hole transporting compound is polymerized or cross-linked using heat or light. When the polymerization reaction is performed by heat, the polymerization initiator may be used in the case where the polymerization reaction proceeds only with thermal energy. Although it may be necessary, it is preferable to add an initiator in order to advance the reaction efficiently at a lower temperature.

  In the case of polymerization by light, it is preferable to use ultraviolet light as light, but the reaction rarely proceeds only by light energy, and a photopolymerization initiator is generally used in combination. The polymerization initiator in this case mainly absorbs ultraviolet rays having a wavelength of 400 (nm) or less, generates active species such as radicals and ions, and initiates polymerization. In the present invention, the aforementioned heat and photopolymerization initiator can be used in combination.

  The charge transport layer 53 having a network structure formed in this manner has high wear resistance, but has a large volume shrinkage during the crosslinking reaction, and if it becomes too thick, cracks and the like may occur. In such a case, the protective layer 54 has a laminated structure, a protective layer of a low molecular weight dispersion polymer is used for the lower layer (photosensitive layer side), and a protective layer having a cross-linked structure is formed on the upper layer (surface side). Also good.

  By using the photosensitive drum 1 as an image carrier having a very hard protective layer provided on the surface layer as described above, the cleaning member and brush of the image forming apparatus of the present invention are maintained without impairing the function as the photosensitive layer. The so-called photoconductor film scraping phenomenon due to the member 3 can be prevented.

  By providing a very hard protective layer on the surface layer of the photosensitive drum 1, it was possible to prevent the photosensitive drum 1 from being scraped by the blade member 3 and the brush member 3. Further, by dispersing the charge transport material in the structure of the binder resin, the function as the photosensitive layer can be prevented from being impaired, and the wear resistance of the photosensitive drum 1 can be improved.

(Corresponding to claim 7):
5 shows a photosensitive drum 1, a charging roller 21 as a charging device, a developing device 22, a cleaning device 23, a lubricant application device (solid lubricant 2, brush member 3, lubricant application auxiliary member 5, spring member 61. 2 is a cross-sectional view showing a schematic configuration in which the image forming apparatus main body is integrally coupled as a process cartridge 100 attached to a common support 95 and is detachable from the image forming apparatus main body. That is, the photosensitive drum 1 as an image carrier, the charging roller 21 for charging the photosensitive drum 1, the developing device 22 for developing the photosensitive drum 1 with toner, and the toner remaining on the photosensitive drum 1 are removed. The cleaning device 23 and the lubricant application device (solid lubricant 2, brush member 3, lubricant application auxiliary member 5, spring member 61), which is a feature of the present invention, are held by a common support member. The process cartridge may be configured to include at least the photosensitive drum 1, the cleaning device 23, and the lubricant application device.

  In this example, the lubricant application device is mounted on the process cartridge, but the lubricant does not scatter. In general, such an electrophotographic image forming apparatus has a complicated structure, and it is often difficult to easily replace each apparatus constituting the image forming apparatus. By using a process cartridge that integrally supports devices that require replacement or the like, the replacement or the like is facilitated, maintenance is improved, and convenience is improved.

  In order to compare the image forming apparatus of the present invention provided with the lubricant application device provided with the lubricant application auxiliary member 5 and the conventional image forming apparatus, an experiment was conducted with IPSiO SP C411 made by RICOH.

  A part of the configuration of the image forming apparatus of the present invention is a process cartridge as in the example of FIG. 5, and the conventional data uses the process cartridge of IPSiO SP C411 as it is. FIG. 6 is data showing the relationship between the consumption amount of the solid lubricant and the weight of the lubricant applied to the photosensitive drum 1. A broken line L3 indicates an ideal straight line. That is, the solid lubricant is entirely applied to the photosensitive drum. In the conventional configuration, as shown by the thin line L1, only about 40 (%) of the solid lubricant is applied to the photosensitive drum, whereas in the configuration of the present invention, as shown by the thick solid line L2, the ideal Although no data has been reached, about 80% solid lubricant was applied to the photosensitive drum 1.

1 is a front view showing a part configuration showing a schematic configuration of an image forming apparatus according to the present invention. It is a figure explaining the mode of lubricant particles around a brush. It is a figure explaining the application | coating function of the lubricant to the photoreceptor drum by the lubricant fixing member, and the lubricant removal function from a brush. It is sectional drawing of a photoconductor drum. It is the schematic front view which showed the process cartridge and its structural member. 3 is data showing the relationship between the amount of solid lubricant consumed and the amount of lubricant applied to the photosensitive drum. FIG. 10 is a front view illustrating a schematic configuration of a conventional image forming apparatus. It is a figure explaining the mode of application of a lubricant to a photosensitive drum. It is a figure explaining a mode that a lubricant to a photosensitive drum is scattered without being applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 2 (as an image carrier) Solid lubricant 3 Brush member 5 Lubricant application auxiliary member 7 Charging device 8 Exposure device 9 Developing device 10 Transfer device 11, 23 Cleaning device 12 Static eliminating device 21 Charging roller 22 Development Apparatus 50 conductive support 51 subbing layer 52 charge generation layer 53 charge transport layer 54 surface protective layer 60 transfer region 61 spring member 90 development region 95 support 100 process cartridge A, B, C, E arrow P recording material

Claims (7)

An image carrier that carries a toner image and moves on the surface, a charging device that charges the image carrier, a latent image forming unit that forms an electrostatic latent image on the charged image carrier, and the image carrier A developing device that visualizes the electrostatic latent image as a toner image, a transfer device that transfers the toner image on the image carrier to a transfer material, and a cleaning that removes unnecessary toner adhering to the surface of the image carrier In an image forming apparatus having an apparatus, and a lubricant application device including a solid lubricant and a rotating brush member for applying the solid lubricant to the image carrier,
The lubricant application device is disposed upstream of the cleaning device in the rotation direction of the image carrier, and a lubricant application auxiliary member is provided near the exit side of the nip portion in the brush rotation direction of the contact nip portion between the image carrier and the brush member. The image forming apparatus is characterized in that one end side of the lubricant application auxiliary member is in contact with the brush member and the other end side is close to the image carrier. An image carrier that carries a toner image and moves on the surface, a charging device that charges the image carrier, a latent image forming unit that forms an electrostatic latent image on the charged image carrier, and the image carrier A developing device that visualizes the electrostatic latent image as a toner image, a transfer device that transfers the toner image on the image carrier to a transfer material, and a cleaning that removes unnecessary toner adhering to the surface of the image carrier In an image forming apparatus having an apparatus, and a lubricant application device including a solid lubricant and a rotating brush member for applying the solid lubricant to the image carrier,
The lubricant application device is arranged upstream of the cleaning device in the rotation direction of the image carrier, and the brush member is disposed near the exit side of the nip portion in the brush rotation direction of the contact nip portion of the image carrier and the brush member. An image forming apparatus comprising: a lubricant application assisting member that dams up lubricant particles that attempt to move to the outside of the nip portion along with rotation of the toner particles and guides the particles to the surface of the image carrier. An image carrier that carries a toner image and moves on the surface, a charging device that charges the image carrier, a latent image forming unit that forms an electrostatic latent image on the charged image carrier, and the image carrier A developing device that visualizes the electrostatic latent image as a toner image, a transfer device that transfers the toner image on the image carrier to a transfer material, and a cleaning that removes unnecessary toner adhering to the surface of the image carrier In an image forming apparatus having an apparatus, and a lubricant application device including a solid lubricant and a rotating brush member for applying the solid lubricant to the image carrier,
The lubricant application device is disposed upstream of the cleaning device in the rotation direction of the image carrier, and the lubricant is applied to the contact nip portion of the image carrier and the brush member in the vicinity of the exit side of the nip portion in the brush rotation direction. An auxiliary member is provided, and one end side of the lubricant application auxiliary member is placed in contact with the brush member, and the other end side is disposed close to the image carrier. An image forming apparatus characterized in that lubricant particles to be moved are dammed and guided to the surface of the image carrier. The image forming apparatus according to any one of claims 1 to 3,
The image forming apparatus according to claim 1, wherein the lubricant application auxiliary member is a strip-shaped member that contacts the brush member, and has a function of removing deposits attached to the brush member. The image forming apparatus according to claim 1,
The image forming apparatus, wherein the solid lubricant is zinc stearate. The image forming apparatus according to claim 1,
An image forming apparatus, wherein a protective layer using a binder resin having a crosslinked structure is provided on a surface layer of the image carrier, and a charge transport material is further included in the structure of the binder resin.   The image carrier, the charging device, the developing device, the cleaning device, and the lubricant applying device according to claim 1, wherein at least the image carrier, the cleaning device, and the lubricant applying device are included. An image forming apparatus characterized in that it is integrally coupled as a process cartridge and is detachable from the main body of the image forming apparatus.

Images