JP2005077632A - Electrophotographic apparatus and method for removing toner on latent image retainer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning mechanism which prevents toner aggregates from depositing on the surface of a cleaning blade of scraping toner remaining on the surface of the photoreceptor, prevents picture quality from being deteriorated on the subsequent image forming process even when the remainder of the scraping by means of the cleaning blade is caused, and exhibits high cleaning efficiency over a long term. <P>SOLUTION: The cleaning device is composed of an application roller that applies cleaning liquid onto the surface of photoreceptor, the cleaning blade that scrapes transfer remaining toner together with the cleaning liquid and a first cleaning roller that is arranged in contact with the downstream side of the blade. Even when the scraping remainder by means of the blade is caused, the first cleaning roller arranged on the downstream side removes the scraping remainder and, therefore, the defective cleaning occuring on a receptor as the scraping remainder by means of the cleaning blade can be prevented. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus that forms an image using a liquid developer, and more particularly, cleaning for cleaning toner particles remaining after an image developed with a developer containing a carrier liquid and toner particles is transferred to a recording medium. The present invention relates to a method and a cleaning mechanism.

  An electrophotographic recording method and an electrostatic recording method using a liquid developer have advantages that cannot be realized by the dry method, and their value is being reviewed in recent years.

  In particular, an image-on-image (hereinafter abbreviated as IOI) color electrophotographic process using a liquid toner (developer) in which a fine toner is dispersed in a solvent is an extremely fine submicron size. High image quality can be achieved by using a simple toner, it is economical because a sufficient amount of image density can be obtained with a small amount of toner, and it can realize a texture similar to that of offset printing, and the toner can be fixed on paper at a relatively low temperature. With the advantages such as energy saving, it is expected that the running cost is lower than the dry electrophotographic process and color recording with the same quality as printing.

  In the electrophotographic process using liquid toner, the toner image on the photoconductor immediately after development contains a large amount of excess developer, so a drying step is provided before transfer of the toner image to paper, and the excess developer It has already been put to practical use.

  However, after the toner image dried in the drying process is transferred to the transfer medium, the toner remaining on the photoreceptor or the intermediate transfer body is heated by the heat provided in the drying process (or transfer to the intermediate transfer body). It is known to be firmly fixed (filmed) to a photoreceptor or an intermediate transfer member. Further, the filmed toner adheres firmly to the photoreceptor or intermediate transfer member such that it cannot be removed by ordinary blade cleaning.

  In an image forming apparatus using a liquid developer, it is necessary to remove the toner adhering to the photosensitive member or the intermediate transfer member even in the conventional method that does not involve the above-described drying step or transfer to the intermediate transfer member. There have been proposed examples of cleaning toner particles dispersed in a liquid solvent by introducing a large amount of the liquid solvent into a cleaning device and removing the liquid solvent using a roller or a blade. (For example, Patent Document 1).

  Further, as a cleaning device, there is also proposed a method in which a sponge roller and a blade are disposed downstream thereof, and the toner adhered thereto is swollen by periodically supplying a cleaning liquid to the sponge roller and scraped off by the blade (for example, Patent Document 2).

Further, as a proposal by a research group including the inventors of the present invention, a cleaning device using a web has also been proposed (for example, Patent Document 3).
Japanese Examined Patent Publication No. 63-4177 Japanese Patent Laid-Open No. 3-185479 JP 2002-23577 A

  However, in the cleaning device described in Patent Document 1, when trying to obtain a good cleaning result, the device becomes complicated, and as a result, the size of the device is increased, and a problem such as causing a failure is remarkable. In particular, there is a problem that the supply and recovery mechanism of the liquid solvent is complicated and the cost is increased.

  Further, in the method disclosed in Patent Document 2, as the cleaning liquid, the developer is supplied from the developer tank through the supply pipe to the sponge roller, and the developer that has flowed to the bottom of the cleaning device is scraped off. Including, it is returned to the developer tank through the recovery tube. However, when the blade is used continuously for a long time, the transfer residue scraped off by the blade gradually adheres to the contact surface of the blade. The transfer residual toner contained in the scraped waste liquid exhibits a compressed and aggregated shape due to film formation, and accumulates on the blade even when the cleaning liquid is constantly supplied, and becomes a lump of toner aggregate. .

  This phenomenon tends to be further accelerated in an image forming apparatus that includes a drying step (or intermediate transfer) for achieving a high-speed process and in which the photoreceptor surface temperature is set to a temperature higher than room temperature. Further, when a massive aggregate of toner aggregates is generated on the blade, there is a problem that it is difficult to uniformly press the blade against the surface of the photoreceptor, and the toner is not easily scraped off. Note that if scraping by the blade occurs, the next image forming process is performed with the adhered material remaining on the surface of the photosensitive member, so that a high-quality image cannot be obtained continuously. Occurs.

  On the other hand, the proposal described in Patent Document 3 excels in maintaining the image quality, but requires a web as a consumable.

  The object of the present invention is to prevent toner aggregates from accumulating on the surface of the cleaning blade that scrapes off the toner remaining on the surface of the photosensitive member. It is an object of the present invention to provide a cleaning mechanism that can reduce the decrease in the temperature and obtain a high cleaning efficiency over a long period of time.

  The present invention removes the liquid developer remaining on the surface of the image carrier together with the cleaning liquid by contacting the surface of the image carrier with a cleaning liquid supply means for supplying a cleaning liquid to the image carrier. A first cleaning means; a release means for releasing the first cleaning means from contact with the surface of the image carrier; and the image carrier after the first cleaning means is released from contact with the image carrier. An electrophotographic apparatus comprising: a second cleaning unit that removes the cleaning liquid on the body surface; and a third cleaning unit that removes deposits attached to the first cleaning unit. .

The present invention also provides a cleaning liquid supplying means for supplying a cleaning liquid to the image carrier and a liquid developer that is brought into contact with the surface of the image carrier at a predetermined pressure and removes the liquid developer remaining on the surface of the image carrier together with the cleaning liquid. First cleaning means, releasing means for releasing the first cleaning means from contact with the surface of the image carrier, and after the first cleaning means is released from contact with the image carrier, the image In the electrophotographic apparatus, comprising: a second cleaning unit that removes the cleaning liquid on the surface of the carrier; and a third cleaning unit that removes deposits attached to the first cleaning unit.
The cleaning liquid includes a carrier liquid that is used for the liquid developer and in which a toner that can be attached to the first cleaning unit and the image carrier is dispersed. The first cleaning unit and the image carrier The second adhering toner is softened to the peripheral surface of the image carrier downstream of the first cleaning unit in the direction in which the peripheral surface of the image carrier is moved. The cleaning liquid that is in contact with the surface of the image carrier and the toner remaining on the surface of the image carrier are scraped and removed. In contact with the first cleaning means while being released from contact with the surface of the carrier, it adheres to the first cleaning means. Characterized in that it is intended to remove the toner.

  Further, the present invention applies a cleaning liquid mainly composed of a carrier liquid to the latent image holding body and the transfer residual toner on the latent image holding body, and removes the transfer residual toner on the surface of the latent image holding body together with the cleaning liquid using a blade, The blade is separated from the latent image holding member, and after the blade is separated from the latent image holding member, the cleaning liquid remaining on the surface of the latent image holding member is removed, and the toner on the latent image holding member is removed. A method is provided.

Furthermore, in the present invention, a cleaning liquid mainly composed of a carrier liquid is applied to the latent image holding body and the transfer residual toner on the latent image holding body, and the transfer residual toner on the surface of the latent image holding body is removed together with the cleaning liquid by a blade. The toner on the latent image holding member is removed by separating the blade from the latent image holding member and removing the cleaning liquid remaining on the surface of the latent image holding member after the blade is separated from the latent image holding member. In the way to
After the image developed from the latent image carrier is transferred to the recording medium, the application roller for applying the cleaning liquid and the cleaning liquid on the surface of the latent image carrier are removed when the operation of the image forming apparatus is stopped. Each of the first cleaning rollers is separated from the latent image holding member.

  The present invention relates to an application roller for applying a cleaning liquid mainly composed of a carrier liquid to a surface of a photoconductor as a cleaning mechanism for removing residual toner remaining on the surface of the photoconductor after a toner image is transferred to a recording medium, and an application roller. A cleaning blade that is placed in contact with the surface of the photoreceptor downstream and scrapes off the transfer residual toner together with the cleaning liquid. A cleaning blade that is placed in contact with the photoreceptor surface downstream of the cleaning blade and collects the cleaning liquid and residual toner remaining on the surface of the photoreceptor. A first cleaning roller that performs cleaning, a second cleaning roller that cleans the cleaning blade, and a separation mechanism that separates the cleaning blade from the photoreceptor, and after the cleaning blade is separated from the surface of the photoreceptor after image formation is completed. Cleaning applied by application roller The removal by the first cleaning roller. In addition, the dirt adhering to the cleaning blade is removed by contacting the second cleaning roller in the separated state. Further, even when the scraping residue by the cleaning blade occurs, the scraping residue is removed by the first cleaning roller, so that it is possible to prevent a cleaning failure from occurring. Note that even if the cleaning liquid is leaked by separating the cleaning blade from the surface of the photosensitive member, it can be removed by the first cleaning roller, and the surface of the photosensitive member can be kept clean.

  On the other hand, the cleaning liquid is mainly composed of a carrier liquid. When the surface of the photoconductor is cleaned only by the first cleaning roller, the carrier liquid is dried even if the cleaning liquid remains thin on the surface of the photoconductor. By doing so, the image quality is not deteriorated.

  Since the cleaning blade is separated from the photosensitive member (released from contact with the photosensitive member) when the apparatus is stopped after image formation is finished, the cleaning blade mainly composed of urethane rubber or the like deteriorates. There is nothing. Further, since the application roller and the first cleaning roller are separated from the surface of the photosensitive member when the operation of the image forming apparatus is stopped, the cleaning roller made of a sponge layer mainly composed of urethane resin may be deteriorated. Absent.

  As described above, according to the present invention, in an image forming apparatus using a liquid developer such as a wet electrophotographic apparatus, it is possible to more reliably and easily perform cleaning of a photosensitive member that is a latent image holding body, An image forming apparatus having a long life can be realized.

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

  In the above-described electric field transfer, we suppress the disturbance of the image caused by air blowing, prevent the toner image from being filmed, and use a method mainly using the elastic force and frictional force of rubber, which is different from electric field transfer. A certain shearing transfer was developed and a good transfer was realized.

  FIG. 1 shows a schematic diagram of the IOI color electrophotographic process that we have developed.

  Around the image carrier, that is, the photosensitive drum (latent image carrier) 1, Y (Yellow, that is, yellow), M (Magenta, which is constituted by charging, exposure, and development for each arbitrary color component according to subtractive color mixing. In other words, K (Kuro) four-color image forming units (at least the charger 2 and the developer 4 respectively) used for reinforcing black and C (Cyan, i.e. bluish purple) and black, and for forming a black image. For identification, the subscripts “−1” to “−4” are added for each color for identification) 2-1 and 4-1, 2-2 and 4-2, 2-3 and 4-3 , And 2-4 and 4-4. In each image forming unit, image light that forms an electrostatic latent image on the photosensitive drum 1 by an arbitrary method, for example, laser beams 3-1 to 3-4, is provided between the charger 2 and the developing device 4. Irradiated. That is, an electrostatic latent image is formed on the upstream side of the developing device 4 of each image forming unit of the photosensitive drum 1 by laser exposure.

  The photosensitive drum 1 is provided with a photosensitive layer such as an organic type or amorphous silicon type on a cylindrical (drum) conductive substrate, for example, and is defined in parallel with the axis of the outer peripheral surface by a motor (not shown). One arbitrary point is moved at a predetermined moving speed (hereinafter referred to as drum peripheral speed). The photosensitive drum 1 is controlled so that the surface temperature is in the range of 38 to 42 ° C. Although not described in detail, instead of the photosensitive drum 1, a conductive film having a photosensitive layer formed on a cylindrical support may be wound to form a drum shape. Further, the conductive film may be a belt shape.

  Although the charger 2 (2-1 to 2-4) is not described in detail, for example, a known corona charger or a scorotron charger is used.

  Although not described in detail, the developing device 4 (4-1 to 4-4) includes a developing roller, and in a known petroleum-based insulating solvent, that is, a carrier liquid (trade name Isopar L, manufactured by Exxon Corporation) in any color. This is a wet developing device using a liquid developer (liquid toner) in which toner, which is colored resin particles, is dispersed. The resin particles used for the toner are approximately spherical with an average particle diameter of about 0.6 μm by, for example, a polymerization method by adding a pigment and a charge control agent to a thermoplastic resin having a glass transition point of 45 ° C.

  With respect to the direction in which the photosensitive drum 1 is rotated, four colors are stacked on the photosensitive drum 1 at predetermined positions downstream of the fourth image forming unit (in this example, the developing device 4-4). A drying mechanism 5 for drying the toner image and a solvent recovery unit 6 for recovering the solvent vapor generated by the drying mechanism 5. The toner image on the photosensitive drum 1 has a residual amount of solvent in a predetermined amount. After being dried to the point, it is once transferred to the primary transfer (intermediate transfer) roller 7 and then transferred to the paper (recording medium) 9 supplied between the secondary transfer roller 8 and the primary transfer roller 7.

  The primary transfer roller 7 is formed by forming an elastic layer on the surface of a stainless steel hollow roller having an outer diameter of 100 mm, for example. Further, although not shown, the elastic layer has a hardness of (JIS-A, JIS-A, through a 0.13 mm thick resin base layer (PET, ie, a polyethylene terephthalate layer) with a 0.03 mm thick silicone-based resin adhesive layer. Thereafter, JIS-A is abbreviated as a notation of hardness, and only the frequency is shown). The elastic film is formed by laminating a silicone layer having a thickness of 0.2 mm at 50 °, and is disposed on the surface of a stainless steel roller.

  On the other hand, the secondary transfer roller 8 includes a heater (not shown) inside a hollow stainless steel roller having an outer diameter of 50 mm, for example, and can heat the sheet 9 passing between the primary transfer roller 7 to a predetermined temperature. Further, a load of 100 kg, for example, is applied to the secondary transfer roller 8 in the direction toward the primary transfer roller 7.

  In such an IOI color electrophotographic process, a first color electrostatic latent image is formed on the photosensitive drum 1 by the first laser exposure 3-1, and a liquid developer containing the first color toner is applied. The held first developing device 4-1 visualizes the electrostatic latent image of the first color. The liquid developer, that is, the toner and the solvent adhering to the electrostatic latent image of the first color may be directly transferred to the sheet 9 by the primary transfer roller 7 and the secondary transfer roller 8 through the drying process including the drying mechanism 5. However, in the example shown in FIG. 1, the second electrostatic latent image is continuously formed by the second charger 2-2 and the second laser exposure 3-2, and is stored in the first developer 4-1. Further development is performed by the second developing device 4-2 holding a developer of a second color different from the toner of the liquid developer.

  Accordingly, when the second development is completed by the second developing device 4-2, a two-color toner image is formed on the latent image holding member 1. Similarly, the third and fourth developments are performed by the third developer 4-3 holding the third color developer and the fourth developer holding the fourth color developer, and the photosensitive drum In 1, a full-color toner image is formed with four color toners.

  The four color toner images formed on the photosensitive drum 1 are proposed by the inventors of the present application, and the primary transfer roller 7 by shearing transfer (non-electric field transfer) already disclosed in Japanese Patent Laid-Open No. 2000-347520 and the like. Are collectively transferred to the paper 9 and secondarily transferred to the paper 9. In the shearing transfer by the present inventors, the speed at which an arbitrary position along the axis of the surface of the primary transfer roller 7 is moved (hereinafter referred to as roller peripheral speed) is the drum peripheral speed of the photosensitive drum 1. The four color toners in a stacked state in the nip (elastic deformation region of the elastic layer) generated on the transfer roller 7 side in the nip region between the primary transfer roller 7 and the photosensitive drum 1 This is a transfer method for transferring images in a batch. Further, the speed difference between the roller peripheral speed of the primary transfer body roller 7 and the drum peripheral speed of the photosensitive drum 1 is 3%, and the drum peripheral speed is made faster than the roller peripheral speed.

    [Embodiment 1] Embodiment 1 of the present invention will be described with reference to FIGS.

  FIG. 2 is a cross-sectional view schematically showing the configuration of the cleaning mechanism 10.

  As shown in FIG. 2, the cleaning mechanism 10 includes an application roller 10-1 that applies a cleaning liquid 10-8 mainly composed of a petroleum insulating solvent that is a carrier liquid to the surface of the photoreceptor 1, and untransferred toner. The cleaning blade 10-2 is scraped off together with the cleaning liquid 10-8, and the first cleaning roller 10-3 is disposed downstream of the cleaning blade 10-2 and is in contact with the surface of the photoreceptor 1.

  The application roller 10-1 is a sponge roller having a diameter of 20 mm in which a urethane sponge layer is formed on a metal shaft. The application roller 10-1 is against the photoreceptor 1 by a motor (or a drive transmission mechanism) (not shown). The outer peripheral surface of the photoreceptor 1 is moved in a direction opposite to the direction in which the outer peripheral surface of the photosensitive member 1 is moved at the contact position) at a predetermined speed.

  The cleaning blade 10-2 is made of urethane rubber having a thickness of 3 mm, for example, and contacts the surface of the photoreceptor 1 with a predetermined pressure, thereby scraping off the untransferred toner together with the cleaning liquid 10-8.

  The first cleaning roller 10-3 is a 20 mm diameter sponge roller in which a urethane sponge layer is formed on a metal shaft. The first cleaning roller 10-3 is against the photoreceptor 1 by a motor (or drive transmission mechanism) (not shown). The outer peripheral surface of the photosensitive member 1 is moved in a direction opposite to the direction in which the outer peripheral surface of the photosensitive member 1 is moved at a position in contact with the outer peripheral surface.

  A waste liquid tray 10-10 that receives the waste liquid scraped by the cleaning blade 10-2 is provided on the downstream side of the cleaning blade 10-2. A second cleaning roller 10-4 that is not always in contact with the surface of the photoreceptor 1 is disposed in the waste liquid tray 10-10. The waste liquid scraped off by the cleaning blade 10-2 flows down to the waste liquid tray 10-10 through a hole (or a gap) (not shown) provided on the side opposite to the contact surface of the photoreceptor 1. The second cleaning roller 10-4 is, for example, a sponge roller having a diameter of 15 mm in which a urethane sponge layer is formed on a metal shaft, and is rotated clockwise (CW) or counterclockwise (by a motor (or drive transmission mechanism) not shown). CCW) can be selectively rotated in any direction.

  The coating liquid 10-1 and the second cleaning roller 10-4 are supplied with the cleaning liquid 10-8 from the cleaning liquid tank 10-7 through the liquid supply shaft 10-5 and the liquid supply pipe 10-9, respectively. Is done. The liquid supply shaft 10-5 is an aluminum pipe having an outer diameter of 6 mm and an inner diameter of 5 mm. Holes having a diameter of 1 mm are formed at intervals of 20 mm in a portion facing the application roller 10-1, and the application roller 10-1 is driven. The cleaning liquid 10-8 is supplied at a predetermined flow rate in synchronization with the above.

  To the peripheral surfaces of the application roller 10-1 and the second cleaning roller 10-4, the toner adhering to the application roller 10-1 and the second cleaning roller 10-4 and the photosensitive member 1 are conveyed. A scraper 10-6 that removes foreign matters such as powder to be transferred, that is, recording paper powder, is in contact with a predetermined pressure. The scraper 10-6 was made of a metal plate having a thickness of 1 mm, for example, and was scraped off through a hole (or a gap) provided on the side opposite to the contact surface with the rollers 10-1 and 10-4. The dirt is guided to the waste liquid tray 10-10.

  FIG. 3 is a schematic diagram for explaining an example of the operation of the cleaning mechanism 10 shown in FIG. 3A illustrates the operation of the cleaning mechanism 10 during continuous image formation, FIG. 3B illustrates the operation of the cleaning mechanism 10 at the end of image formation, and FIG. 3C illustrates the image forming apparatus. The operation of the cleaning mechanism 10 when the power is turned off (immediately before the apparatus is shut down) is shown.

  As shown in FIG. 3A, during a normal image forming operation, for example, about 5 cc / min is synchronized with the driving of the application roller 10-1 of the cleaning mechanism 10 via the liquid supply shaft 10-5. The cleaning liquid 10-8 is supplied at a flow rate.

  Since the scraper 10-6 is in contact with the outer peripheral surface of the coating roller 10-1 with a predetermined pressure, the toner to be transferred, that is, the material to be transferred conveyed along with the rotation of the photosensitive member 1, Foreign matter such as powder on the recording paper flows down to the cleaning blade 10-2. Further, since the cleaning blade 10-2 is in contact with the surface of the photoconductor 1 at a predetermined pressure, the cleaning liquid 10-8 supplied to the coating rotor 10-1 and the residual dissolved in the surface of the photoconductor 1 by the cleaning liquid. The toner is carried from a waste liquid tray 10-10 to a waste liquid tank (not shown) via a waste liquid recovery pipe 10-11.

  Even if the cleaning liquid 10-8 and the melted toner that could not be removed by the cleaning blade 10-2 leaked, they are removed by the first cleaning roller 10-3. It became possible to prevent the decline.

  On the other hand, the role of the application roller 10-1 is mainly to apply the cleaning liquid 10-8 to the surface of the photoconductor 1. Adhering is unavoidable, and the cleaning liquid 10-8 can be more uniformly applied to the surface of the photoreceptor 1 by removing the toner and foreign matter adhering to the scraper 10-6.

  FIG. 3B shows the operating state of the cleaning mechanism 10 at the end of image formation.

  When image formation for a predetermined number of times set from an operation panel (not shown) or an external device is completed, the cleaning blade 10-2 is separated from the photoreceptor 1 by a drive mechanism (not shown), and the application roller 10-1 and the first cleaning roller 10- Only 3 is brought into contact with the photoreceptor 1.

  Accordingly, the cleaning liquid and the toner, that is, the scraping liquid (waste liquid) partially blocked by the cleaning blade 10-2 become “drip” and flow downward from the photoreceptor 1, but the first cleaning roller 10-3. Removed. However, since thin dirt remains on the surface of the photoconductor 1 after the “drip” is removed, a predetermined amount of the cleaning liquid 10-8 is applied to the surface of the photoconductor 1 by the application roller 10-1, and this is applied to the first surface. It is preferable that the photosensitive member 1 is rotated by two or three extra rotations while being removed by the cleaning roller 10-3. As a result, the waste liquid and residual toner on the surface of the photoreceptor 1 were completely removed.

  FIG. 3C shows the operating state of the cleaning mechanism 10 immediately before the apparatus is shut down (the image forming apparatus is powered off).

  After completion of the cleaning of the surface of the photosensitive member 1 described with reference to FIG. 3B, the entire cleaning mechanism 10 is separated from the surface of the photosensitive member 1 by a driving mechanism (not shown), whereby the application roller 10-1 and the first cleaning roller 10 are separated. -3 is also released from contact with the surface of the photoreceptor 1.

  Subsequently, the second cleaning roller 10-4 is brought into contact with the tip of the cleaning blade 10-2 (the side in contact with the photoreceptor 1) by a driving mechanism (not shown).

  Next, in synchronization with the driving of the second cleaning roller 10-4, the cleaning liquid 10-8 is, for example, at a flow rate of about 5 cc / min via the liquid supply shaft 10-5 and the second cleaning roller 10-4. To be supplied. The second cleaning roller 10-4 is rotated clockwise or counterclockwise or in both directions at a predetermined timing by a drive mechanism (or motor) (not shown). At this time, the contact angle of the cleaning blade 10-2 with the second cleaning roller 10-4 is appropriately changed by a driving mechanism (not shown). As a result, the toner aggregates deposited on the contact surface and the tip of the photosensitive member 1 of the cleaning blade 10-2 are removed. Note that the process shown in FIG. 3C is called self-cleaning. Further, in a state where the entire cleaning mechanism is separated from the surface of the photoreceptor, the rollers are rotated while supplying the cleaning liquid to the coating roller 10-1 and the second cleaning roller 10-4, respectively, and the scraper is attached to the roller surface. A step of removing may be added.

  According to the above operation procedure, after printing 100,000 sheets for the A4 format in the state of FIG. 3A, the image formation is finished, the surface of the photoreceptor 1 is cleaned in the state of FIG. Blade cleaning was performed in the state of (c).

  At this time, the surface of the photoconductor maintained a clean surface similar to that in the initial state, and no lump deposits were observed on the blade. It was also confirmed that the printed image obtained a high-quality image as in the initial image.

  In the first embodiment shown in FIG. 2, the liquid supply shaft 10-6 close to the application roller is used as the means for supplying the cleaning liquid 10-8 to the application roller 10-1. As shown, the same effect can be obtained by supplying the cleaning liquid 10-8 directly between the application roller 10-1 and the photoreceptor 1 by the liquid supply nozzle 10-12. Further, the cleaning liquid 10-8 may be directly supplied to the surface of the photoreceptor 1. The cleaning liquid 10-8 supplied from the nozzle 10-12 is not limited to liquid but may be mist.

  As described above, the first cleaning roller disposed on the downstream side removes the scraping residue even when scraping residue by the cleaning blade is generated on the surface of the photosensitive member by the cleaning mechanism of the first embodiment of the present invention. Since it is removed, the occurrence of cleaning failure can be prevented.

  Also, after the image formation is completed, the cleaning blade is released from contact with the surface of the photoconductor, so that the waste liquid drips out. Good cleaning was completed by removing with a cleaning roller. Even when a developer is used as a cleaning liquid and the cleaning liquid is thinly dried after cleaning the surface of the photoconductor, there is almost no “toner particles” on the photoconductor, and the image quality in the next image formation Can be prevented.

  On the other hand, the lump-like toner (toner aggregate) fixed to the cleaning blade can be removed by the second cleaning roller, so that the cleaning ability of the cleaning blade alone can be maintained even when used for a long time, and good cleaning becomes possible. .

  In addition, when the apparatus is stopped after the image formation is completed, the cleaning blade and the cleaning roller are both released (separated) from contact with the photosensitive member. It is possible to prevent the cleaning roller composed of a sponge layer mainly composed of urethane resin or the like from deteriorating.

  With these configurations, it is possible to always maintain a good cleaning effect, and it is possible to continuously form high-quality images for a long time.

    [Embodiment 2] Embodiment 2 of the present invention will be described with reference to FIG.

  FIG. 5 is a cross-sectional view schematically showing the configuration of the second embodiment of the cleaning mechanism of the present invention. In addition, the same code | symbol is attached | subjected to the same structure as the structure already demonstrated using FIG. 2, and detailed description is abbreviate | omitted.

  A cleaning mechanism 10 shown in FIG. 5 includes a web cleaner (first surface) disposed in contact with the surface of the photoreceptor 1 on the downstream side of the application roller 10-1, the cleaning blade 10-2, and the cleaning blade 10-2. (Corresponding to a cleaning roller) 10-14. The web cleaner 10-14 is configured such that, for example, a non-woven fabric made of polyester is supplied along the outer peripheral surface of a rubber roller (not described in detail), and the non-woven fabric is brought into contact with the surface of the photoreceptor 1 with a predetermined pressure via the rubber roller. The non-woven fabric is wound around a supply roller (not shown) for a predetermined length, and is taken up by a take-up roller (not shown) every predetermined time or a predetermined number of times of image output. Accordingly, the nonwoven fabric in contact with the surface of the photoreceptor 1 is given an appropriate tension and feed speed, and residual toner scrapes and dripping by the cleaning blade on the surface of the photoreceptor 1 and excess carrier liquid are removed from the surface of the photoreceptor 1. Can be removed.

  The brush roller 10-13 is a roller having a 15 mm outer diameter in which, for example, a layer in which a polyester fiber having a diameter of 0.5 mm or artificial hair is embedded in a loop shape on a metal shaft, is rotated clockwise by a motor (not shown). Alternatively, it is selectively rotated in either or both counterclockwise directions. Note that the scraper 10-6 is brought into contact with the brush roller 10-13 to remove the dirt attached to the surface of the brush roller 10-13.

  In the cleaning mechanism shown in FIG. 5, the electrostatic latent image formed on the surface of the photoreceptor 1 in the same manner as described in Example 1 with reference to FIG. Developed by adhesion. The toner image formed on the surface of the photoreceptor 1 is subjected to a drying process facing the drying mechanism 5, a predetermined amount of the remaining carrier liquid is removed, and the toner image is primarily transferred to the surface of the primary transfer roller 7 set at 110 ° C. Secondary transfer is performed on the sheet 9 via the next transfer roller 8.

  The surface of the photoconductor 1 after the toner image is transferred to the paper 9 is cleaned by passing through a cleaning area facing the cleaning mechanism 10 by rotating the photoconductor 1 and used for the next image formation.

  In the cleaning process of the surface of the photosensitive member 1 in the cleaning mechanism 10, the region where the second cleaning roller 10-13 is a brush roller and the first cleaning roller 10-14 is in contact with the surface of the photosensitive member 1 is a predetermined time. Alternatively, the above-described implementation is performed except that the absolute amount when the removed residual toner is fixed is controlled by being moved every predetermined number of image formations or sequentially displaced at a predetermined speed. Since it is substantially the same as Example 1, detailed description thereof is omitted.

  In the cleaning mechanism of the second embodiment described above, according to the same operation procedure as that of the first embodiment, after printing 100,000 sheets for the A4 format in the state of FIG. When the surface of the photosensitive member 1 is cleaned in the state of (b) and the cleaning blade is cleaned in the state of FIG. 3 (c), the surface of the photosensitive member keeps the same clean surface as in the initial state. No massive deposits were seen. It was also confirmed that the printed image obtained a high-quality image as in the initial image.

    [Third Embodiment] FIG. 6 shows a third embodiment of the present invention.

  FIG. 6 is a cross-sectional view schematically showing the configuration of the second embodiment of the cleaning mechanism of the present invention. In addition, the same code | symbol is attached | subjected to the same structure as the structure already demonstrated using FIG. 2, and detailed description is abbreviate | omitted.

  The cleaning mechanism 10 shown in FIG. 6 includes an application roller 10-1, a cleaning blade 10-2, and a suction sponge roller (a first sponge roller disposed on the downstream side of the cleaning blade 10-2 in contact with the surface of the photosensitive member 1). (Corresponding to a cleaning roller) 10-15.

  The suction sponge roller 10-15 is a roller in which a urethane sponge layer in which suction holes represented by continuous holes or a plurality of fine slits are provided on the outer periphery of the porous shaft 10-16 is formed. . The suction sponge roller 10-15 is brought into contact with the surface of the photoreceptor 1 with a predetermined pressure. Further, a suction pump 10-18 is connected to one end of the porous shaft 10-16 of the suction sponge roller 10-15 through, for example, a filter 10-17, and the collected waste liquid and toner particles are sucked. The cleaning liquid mainly composed of the carrier liquid from which the toner particles and the like are removed by the filter 10-17 is returned to the cleaning liquid tank 10-19 through the recovery pipe 10-19.

  In the cleaning mechanism shown in FIG. 6, the toner image formed on the surface of the photosensitive member 1 is passed through the primary transfer roller 7 and the secondary transfer roller 8 in the same manner as described in Example 1 with reference to FIG. Then, it is secondarily transferred to the paper 9.

  The surface of the photoconductor 1 after the toner image is transferred to the paper 9 is cleaned by passing through a cleaning area facing the cleaning mechanism 10 by rotating the photoconductor 1 and used for the next image formation.

  It should be noted that the surface of the photosensitive member 1 adsorbed to the suction sponge roller 10-15 by the suction force from the suction pump 10-18 is not scraped off by the cleaning blade 10-2, liquid dripping generated on the surface of the photosensitive member 1, or excessive cleaning. The liquid 10-8 and the like are returned to the cleaning liquid tank 10-19 after the solid matter is removed through the filter 10-17.

  In the cleaning mechanism of the third embodiment described above, according to the same operation procedure as that of the first embodiment, after 100,000 sheets are printed in the A4 format in the state of FIG. 3A and image formation is completed, FIG. When the surface of the photoconductor 1 was cleaned in this state and the cleaning blade was further cleaned in the state shown in FIG. 3C, the surface of the photoconductor maintained a clean surface similar to that in the initial state, and the cleaning blade was also agglomerated. Nothing was seen. It was also confirmed that the printed image obtained a high-quality image as in the initial image. Further, since the cleaning liquid can be circulated and used, resource saving can be realized.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

1 is a schematic diagram (overall schematic diagram) illustrating an example of an image forming apparatus to which an embodiment of the present invention (Examples 1, 2 and 3) can be applied. FIG. 3 is a schematic diagram illustrating an example of a cleaning mechanism (Example 1) applied to the image forming apparatus illustrated in FIG. 1. Schematic explaining an example of the operation of the cleaning mechanism shown in FIG. Schematic explaining an example of a modification of the cleaning mechanism shown in FIG. FIG. 6 is a schematic diagram illustrating an example of a cleaning mechanism (second embodiment) applied to the image forming apparatus illustrated in FIG. 1. FIG. 7 is a schematic diagram illustrating an example of a cleaning mechanism (Example 3) applied to the image forming apparatus illustrated in FIG. 1. Schematic explaining an example of a drying mechanism (Example 3).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Photosensitive drum (latent image holding body), 2 (2-1 to 2-4) ... Charger, 3 (3-1 to 3-4) ... Laser exposure, 4 (4-1 to 4-4) DESCRIPTION OF SYMBOLS Developing device, 5 ... Drying mechanism, 6-1 ... Solvent recovery device, 6-2 ... Solvent recovery tube, 7 ... Primary transfer roller, 8 ... Secondary transfer roller, 9 ... Paper, 10 ... Photoconductor cleaner, 10- DESCRIPTION OF SYMBOLS 1 ... Coating roller, 10-2 ... Cleaning blade, 10-3 ... Second cleaning roller, 10-4 ... Third cleaning roller, 10-5 ... Liquid supply shaft, 10-6 ... Scraper, 10-7 ... Cleaning liquid Tank, 10-8, cleaning liquid, 10-9, liquid supply pipe, 10-10, waste liquid tray, 10-11, waste liquid collection pipe, 10-12, liquid supply nozzle, 10-13, brush roller, 10-14 ... Web cleaner, 10-15 ... Suction sponge roller, 10-1 ... porous shaft, 10-17 ... filter, 10-18 ... suction pump, 10-19 ... recovery pipe.

Claims (4)

Cleaning liquid supply means for supplying a cleaning liquid to the image carrier;
A first cleaning means that contacts the surface of the image carrier at a predetermined pressure and removes the liquid developer remaining on the surface of the image carrier together with the cleaning liquid;
Release means for releasing the first cleaning means from contact with the surface of the image carrier;
Second cleaning means for removing the cleaning liquid on the surface of the image carrier after the first cleaning means is released from contact with the image carrier;
Third cleaning means for removing deposits adhering to the first cleaning means;
An electrophotographic apparatus comprising: The cleaning liquid includes a carrier liquid that is used for the liquid developer and in which a toner that can be attached to the first cleaning unit and the image carrier is dispersed. The first cleaning unit and the image carrier Softens the toner adhering to
The second cleaning unit is in contact with the peripheral surface of the image carrier on the downstream side in the direction in which the peripheral surface of the image carrier is moved relative to the first cleaning unit, and is present on the surface of the image carrier. Scraping and removing the cleaning liquid and the toner remaining on the surface of the image carrier,
The third cleaning unit includes the toner attached to the first cleaning unit by being in contact with the first cleaning unit in a state where the first cleaning unit is released from contact with the surface of the image carrier. The electrophotographic apparatus according to claim 1, wherein the electrophotographic apparatus removes. Apply a cleaning liquid containing a carrier liquid as a main component to the latent image carrier and the toner remaining on the latent image carrier.
The transfer residual toner on the surface of the latent image holding member is removed together with the cleaning liquid by a blade,
Separate the blade from the latent image carrier,
A method for removing toner on a latent image holding member, comprising: removing a cleaning liquid remaining on a surface of the latent image holding member after the blade is separated from the latent image holding member.   After the image developed from the latent image carrier is transferred to the recording medium, the application roller for applying the cleaning liquid and the cleaning liquid on the surface of the latent image carrier are removed when the operation of the image forming apparatus is stopped. 4. The method for removing toner on a latent image holding member according to claim 3, wherein each of the first cleaning rollers is separated from the latent image holding member.

Images