JP2014238448A - Lubricant application device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubricant application device that can apply lubricant uniformly on the surface of a photoreceptor with a simple configuration, and prevent a reduction in image quality due to the deterioration of the photoreceptor or a cleaning blade; and an image forming apparatus.SOLUTION: A lubricant application device 80 includes a lubricant supply part 81 that supplies lubricant to the surface of an image carrier 413 that is driven to rotate, and a leveling blade 84 that is arranged on the downstream side of the lubricant supply part in the direction of rotation of the image carrier 413 and brought into slide contact with the surface of the image carrier 413 to level the lubricant supplied to the image carrier 413 while heating a lubricant application surface of the image carrier 413.

Description

  The present invention relates to a lubricant application device that applies a lubricant to an image carrier and an image forming apparatus including the same.

  In general, in an image forming apparatus (printer, copier, facsimile, etc.) using an electrophotographic process technology, a laser beam based on image data is irradiated (exposed) to a uniformly charged photoreceptor (for example, paper). As a result, an electrostatic latent image is formed on the surface of the photoreceptor. Then, the toner is supplied to the sheet on which the electrostatic latent image is formed, so that the electrostatic latent image is visualized and a toner image is formed. The toner image is transferred directly or indirectly to the sheet via an intermediate transfer member, and then heated and pressed by a fixing device, whereby an image is formed on the sheet.

  Further, toner remaining on the surface of the photoreceptor after transfer (transfer residual toner) is collected by a cleaning device. The cleaning device has a cleaning blade made of an elastic body, which is disposed in a state of sliding in contact with the surface of the photoconductor. The transfer residual toner is scraped off by the cleaning blade, whereby the surface of the photoreceptor is cleaned.

  At this time, since the photosensitive member travels (rotates in the case of paper) with the cleaning blade in sliding contact, a frictional force is generated at the sliding contact portion between the photosensitive member and the cleaning blade, and the photosensitive member and the cleaning blade are worn. There is a problem of deterioration. If the removal efficiency of the transfer residual toner is lowered, image quality may be deteriorated, such as image unevenness. Therefore, the conventional image forming apparatus includes a lubricant application unit that applies a lubricant to the surface of the photoreceptor in order to reduce the frictional force at the sliding contact portion.

  When a lubricant is applied to the photoconductor, the lubricant application brush is generally fixed in a state of being in sliding contact with the photoconductor, and a solid lubricant is pressed against the lubricant application brush. Then, as the lubricant application brush rotates, the solid lubricant is scraped off, and the scraped lubricant is applied to the photoreceptor. The applied lubricant is pushed and spread on the photoreceptor by a leveling member (for example, a leveling blade) disposed on the downstream side in the running direction of the photoreceptor relative to the lubricant application brush.

For example, Patent Documents 1 to 3 are examples of prior art documents related to the lubricant application unit. Patent Document 1 discloses controlling the temperature of a solid lubricant. Patent Document 2 discloses that the scraping amount of the lubricant is controlled by changing the temperature of the lubricant application brush. According to these techniques, the lubricant can be stably supplied to the photoreceptor.
Patent Document 3 discloses controlling the temperature of a leveling member composed of a rotating roller. According to this technique, the lubricant supplied to the photoreceptor can be uniformly applied.

JP-A-7-334055 JP 2010-230903 A JP 2012-234004 A

  However, in the technique described in Patent Document 3, since a rotating roller is applied as a leveling member, a driving motor or the like for driving the rotating roller is required. Therefore, compared with the case where a leveling blade is applied as the leveling member, the configuration becomes complicated and it is difficult to reduce the size.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a lubricant application device and an image forming apparatus that can uniformly apply a lubricant to the surface of a photoconductor with a simple configuration and can prevent image quality deterioration due to deterioration of the photoconductor or a cleaning blade.

A lubricant application device according to the present invention includes a lubricant supply unit that supplies a lubricant to the surface of an image carrier that is rotationally driven,
The lubricant disposed on the downstream side of the lubricant supply unit with respect to the rotation direction of the image carrier, slidingly contacting the surface of the image carrier, and being supplied to the image carrier while heating the lubricant application surface of the image carrier And a leveling blade for leveling.

An image forming apparatus according to the present invention includes an image forming unit that forms a toner image on the image carrier,
A cleaning unit that removes toner remaining on the image carrier after the transfer of the toner image with a cleaning blade;
And a lubricant application device as described above.

According to the lubricant application apparatus of the present invention, the lubricant application surface of the image carrier is uniformly heated at a predetermined temperature, so that the lubricant can be uniformly applied to the surface of the image carrier. Further, unlike the lubricant application device described in Patent Document 3, the lubricant application device does not need to be provided with a drive motor or the like that drives a rotating roller as a leveling member, and thus is realized with an extremely simple configuration.
In addition, according to the image forming apparatus of the present invention, it is possible to effectively prevent the image quality from being deteriorated due to the deterioration of the image carrier or the cleaning blade.

1 is a diagram illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention. It is a figure which shows the principal part structure of the drum cleaning apparatus which concerns on embodiment. It is a figure which shows an example of the leveling blade which concerns on embodiment. It is a figure which shows another example of the leveling blade which concerns on embodiment. It is a figure which shows another example of the leveling blade which concerns on embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing an overall configuration of an image forming apparatus 1 according to an embodiment of the present invention.
An image forming apparatus 1 shown in FIG. 1 is an intermediate transfer type color image forming apparatus using electrophotographic process technology. In the image forming apparatus 1, photosensitive drums 413 corresponding to four colors of CMYK are arranged in series in the running direction (vertical direction) of the intermediate transfer belt 421, and each color toner image is sequentially transferred to the intermediate transfer belt 421 in one procedure. The vertical tandem system is adopted.
That is, the image forming apparatus 1 transfers Y (yellow), M (magenta), C (cyan), and K (black) toner images formed on the photosensitive drum 413 to the intermediate transfer belt 421 (primary transfer). Then, after superimposing the four color toner images on the intermediate transfer belt 421, the toner images are transferred to the paper S (secondary transfer) to form an image.

  As shown in FIG. 1, the image forming apparatus 1 includes an image reading unit 10, an operation display unit 20, an image processing unit 30, an image forming unit 40, a paper transport unit 50, a fixing unit 60, and a control unit 100.

  The control unit 100 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The CPU reads a program corresponding to the processing content from the ROM, develops it in the RAM, and centrally controls the operation of each block of the image forming apparatus 1 in cooperation with the developed program. At this time, various data stored in a storage unit (not shown) are referred to. The storage unit (not shown) is configured by, for example, a nonvolatile semiconductor memory (so-called flash memory) or a hard disk drive.

  Further, the control unit 100 communicates with an external device (for example, a personal computer) connected to a communication network such as a LAN (Local Area Network) or a WAN (Wide Area Network) via a communication unit (not shown). Send and receive various data. For example, the control unit 100 receives image data transmitted from an external device and forms an image on a sheet based on the image data (input image data). The communication unit (not shown) is composed of a communication control card such as a LAN card, for example.

The image reading unit 10 includes an automatic document feeder 11 called an ADF (Auto Document Feeder), a document image scanning device 12 (scanner), and the like.
The automatic document feeder 11 conveys the document placed on the document tray by the conveyance mechanism and sends it out to the document image scanning device 12. The automatic document feeder 11 can continuously read images (including both sides) of a large number of documents placed on a document tray.
The document image scanning device 12 optically scans a document conveyed on the contact glass from the automatic document feeder 11 or a document placed on the contact glass, and reflects light from the document to a CCD (Charge Coupled Device). ) An image is formed on the light receiving surface of the sensor 12a, and an original image is read. The image reading unit 10 generates input image data based on the reading result by the document image scanning device 12. The input image data is subjected to predetermined image processing in the image processing unit 30.

  The operation display unit 20 is configured by, for example, a liquid crystal display (LCD) with a touch panel, and functions as a display unit 21 and an operation unit 22. The display unit 21 displays various operation screens, an image status display, an operation status of each function, and the like in accordance with a display control signal input from the control unit 100. The operation unit 22 includes various operation keys such as a numeric keypad and a start key, receives various input operations by the user, and outputs an operation signal to the control unit 100.

  The image processing unit 30 includes a circuit that performs digital image processing on input image data according to initial settings or user settings. For example, the image processing unit 30 performs tone correction based on tone correction data (tone correction table) under the control of the control unit 100 (image density control). Further, the image processing unit 30 performs various correction processes such as color correction and shading correction, a compression process, and the like on the input image data in addition to the gradation correction. The image forming unit 40 is controlled based on the image data subjected to these processes.

  The image forming unit 40 includes an image forming unit 41 and an intermediate transfer unit 42 for forming an image using colored toners of Y component, M component, C component, and K component based on input image data. The writing range of the image formed by the image forming unit 40 is set in advance.

  The image forming unit 41 includes four image forming units 41Y, 41M, 41C, and 41K for Y component, M component, C component, and K component. Since the image forming units 41Y, 41M, 41C, and 41K have the same configuration, for convenience of illustration and description, common constituent elements are denoted by the same reference numerals, and when distinguished from each other, the reference numerals Y, M, and C are used. Or K. In FIG. 1, reference numerals are given only to the components of the image forming unit 41Y for the Y component, and reference numerals of the constituent elements of the other image forming units 41M, 41C, 41K are omitted.

  The image forming unit 41 includes an exposure device 411, a developing device 412, a photosensitive drum 413, a charging device 414, a drum cleaning device 415, and the like.

The photosensitive drum 413 includes, for example, an undercoat layer (UCL), a charge generation layer (CGL), and a charge transport layer (CTL) on the peripheral surface of an aluminum conductive cylinder (aluminum tube). : A negatively charged organic photoconductor (OPC) in which Charge Transport Layers are sequentially stacked.
The charge generation layer is made of an organic semiconductor in which a charge generation material (for example, phthalocyanine pigment) is dispersed in a resin binder (for example, polycarbonate), and generates a pair of positive charges and negative charges upon exposure by the exposure device 411. The charge transport layer consists of a hole transport material (electron donating nitrogen-containing compound) dispersed in a resin binder (for example, polycarbonate resin), and transports positive charges generated in the charge generation layer to the surface of the charge transport layer. To do.

  The charging device 414 is constituted by a corona discharge generator such as a scorotron charging device or a corotron charging device. The charging device 414 uniformly charges the surface of the photosensitive drum 413 to a negative polarity by corona discharge.

  The exposure apparatus 411 is composed of, for example, a semiconductor laser. The exposure device 411 irradiates the photosensitive drum 413 with laser light corresponding to the image of each color component. The positive charge generated in the charge generation layer of the photosensitive drum 413 is transported to the surface of the charge transport layer, so that the surface charge (negative charge) of the photosensitive drum 413 is neutralized. Thereby, an electrostatic latent image of each color component is formed on the surface of the photosensitive drum 413 due to a potential difference from the surroundings.

  The developing device 412 contains a developer of each color component (for example, a two-component developer composed of a toner having a small particle diameter and a magnetic material), and the toner of each color component is attached to the surface of the photosensitive drum 413. The electrostatic latent image is visualized to form a toner image. Specifically, a developing bias voltage is applied to the developer carrying member, and the charged toner on the developer carrying member is exposed on the surface of the photosensitive drum 413 due to a potential difference between the surface of the photosensitive drum 413 and the developer carrying member. Move to and adhere to.

  The drum cleaning device 415 includes a cleaning unit 90 and a lubricant application unit 80 (see FIG. 2). The cleaning unit 90 includes a drum cleaning blade 91 and the like that are in sliding contact with the surface of the photosensitive drum 413, and removes transfer residual toner remaining on the surface of the photosensitive drum 413 after primary transfer. The lubricant application unit 80 includes a lubricant application brush 81 and a leveling blade 84 that are in sliding contact with the surface of the photosensitive drum 413, and applies the lubricant to the surface of the photosensitive drum 413. Details of the drum cleaning device 415 will be described later.

  The intermediate transfer unit 42 includes an intermediate transfer belt 421, a primary transfer roller 422, a plurality of support rollers 423, a secondary transfer roller 424, a belt cleaning device 426, and the like.

  The intermediate transfer belt 421 is an endless belt, and is stretched around a plurality of support rollers 423 in a loop shape. At least one of the plurality of support rollers 423 is configured by a driving roller, and the other is configured by a driven roller. For example, it is preferable that the roller 423A disposed downstream of the K component primary transfer roller 422 in the belt traveling direction is a drive roller. This makes it easy to keep the belt running speed constant in the primary transfer portion. As the driving roller 423A rotates, the intermediate transfer belt 421 travels in the direction of arrow A at a constant speed.

  The primary transfer roller 422 is disposed on the inner peripheral surface side of the intermediate transfer belt 421 so as to face the photosensitive drum 413 of each color component. The primary transfer roller 422 is pressed against the photosensitive drum 413 with the intermediate transfer belt 421 interposed therebetween, whereby a primary transfer nip for transferring a toner image from the photosensitive drum 413 to the intermediate transfer belt 421 is formed.

  The secondary transfer roller 424 is disposed on the outer peripheral surface side of the intermediate transfer belt 421 so as to face a roller 423B (hereinafter referred to as “backup roller 423B”) disposed on the downstream side of the driving roller 423A in the belt traveling direction. The secondary transfer roller 424 is pressed against the backup roller 423B with the intermediate transfer belt 421 interposed therebetween, thereby forming a secondary transfer nip for transferring the toner image from the intermediate transfer belt 421 to the sheet.

When the intermediate transfer belt 421 passes through the primary transfer nip, the toner images on the photosensitive drum 413 are primarily transferred to the intermediate transfer belt 421 in order. Specifically, a primary transfer bias is applied to the primary transfer roller 422, and an electric charge having a polarity opposite to that of the toner is applied to the back side of the intermediate transfer belt 421 (the side in contact with the primary transfer roller 422). It is electrostatically transferred to the intermediate transfer belt 421.
Thereafter, when the sheet passes through the secondary transfer nip, the toner image on the intermediate transfer belt 421 is secondarily transferred to the sheet. Specifically, a toner image is formed by applying a secondary transfer bias to the secondary transfer roller 424 and applying a charge having a polarity opposite to that of the toner to the back side of the recording paper (side contacting the secondary transfer roller 424). Is electrostatically transferred to the recording paper. The sheet on which the toner image has been transferred is conveyed toward the fixing unit 60.

The belt cleaning unit 426 includes a belt cleaning blade that is in sliding contact with the surface of the intermediate transfer belt 421 and removes transfer residual toner remaining on the surface of the intermediate transfer belt 421 after the secondary transfer.
Instead of the secondary transfer roller 424, a configuration (so-called belt-type secondary transfer unit) in which a secondary transfer belt is looped around a plurality of support rollers including the secondary transfer roller is adopted. Also good.

The fixing unit 60 is arranged on the upper fixing unit 60A having a fixing surface side member arranged on the fixing surface (surface on which the toner image is formed) side of the paper, and on the back surface (surface opposite to the fixing surface) side of the paper. A lower fixing unit 60B having a back-side support member and a heating source 60C. When the back surface side support member is pressed against the fixing surface side member, a fixing nip for nipping and transporting the sheet is formed.
When the upper fixing unit 60A is a belt heating method (see FIG. 1), the fixing belt is a fixing surface side member, and when it is a roller heating method, the fixing roller is a fixing surface side member. Further, when the lower fixing unit 60B is a roller pressurization method (see FIG. 1), the pressure roller is a back surface side support member, and when it is a belt pressure method, the pressure belt is a back surface side support member. .

  The fixing unit 60 fixes the toner image on the sheet by secondarily transferring the toner image and heating and pressurizing the conveyed sheet at the fixing nip. The fixing unit 60 is disposed in the fixing device F as a unit. The fixing device F may be provided with an air separation unit that separates the sheet from the fixing surface side member or the back surface side support member by blowing air.

The paper transport unit 50 includes a paper feed unit 51, a paper discharge unit 52, a first transport unit 53, a second transport unit 54, and the like.
In the three paper feed tray units 511 to 513 constituting the paper feed unit 51, paper (standard paper, special paper) identified based on basis weight, size, or the like is stored for each preset type.

  The first transport unit 53 includes a plurality of transport roller units including an intermediate transport roller unit 531, a loop roller unit 532, and a registration roller unit 533. The first transport unit 53 transports paper fed from the paper feed unit 51 or an external paper feed device (not shown) to the image forming unit 40 (secondary transfer unit).

  The 2nd conveyance part 54 is provided with the switchback path | route 541 and the conveyance path 542 for back surfaces by which the some conveyance roller part is arrange | positioned. The second transport unit 54 once transports the paper to the switchback path 541, switches back and transports the paper to the back-side transport path 542, thereby reversing the paper, and the first transport unit 53 (loop roller unit 532). Upstream).

  A sheet fed from the sheet feeding unit 51 or an external sheet feeding device (not shown) is conveyed to the image forming unit 40 by the first conveying unit 53. Then, when the sheet passes through the secondary transfer nip, the toner image on the intermediate transfer belt 421 is secondarily transferred to one side (front surface) of the sheet at a time, and a fixing process is performed in the fixing unit 60. The paper on which the image is formed is discharged out of the apparatus by a paper discharge unit 52 having a paper discharge roller 52a.

FIG. 2 is a diagram illustrating a main configuration of the drum cleaning device 415 according to the embodiment.
As shown in FIG. 2, the drum cleaning device 415 includes a cleaning unit 90 and a lubricant application unit 80. The constituent members of the cleaning unit 90 and the lubricant application unit 80 are attached to the housing case C that is a frame of the drum cleaning device 415 by an appropriate method.

The cleaning unit 90 includes a drum cleaning blade 91, a toner recovery screw 92, and the like.
The drum cleaning blade 91 is an elastic member obtained by molding urethane rubber or the like into a flat plate shape, and has a width substantially equal to the width of the photosensitive drum 413 in the axial direction (main scanning direction). The drum cleaning blade 91 has a predetermined free length (for example, 9 mm), and has a predetermined contact angle (direction in which the edge portion is stretched when the photosensitive drum 413 rotates) with respect to the photosensitive drum 413 (a direction in which the edge portion is stretched). For example, it is arranged so as to be in sliding contact with a normal load (for example, 20 N).

  During image formation, as the photosensitive drum 413 rotates, the transfer residual toner remaining on the surface of the photosensitive drum 413 is scraped off by the drum cleaning blade 91. The transfer residual toner thus scraped off is sent to a waste toner collection container (not shown) by a toner collection screw 92.

  The lubricant application part 80 includes a lubricant application brush 81, a solid lubricant 82, a lubricant pressing part 83, a leveling blade 84, and the like.

  The lubricant application brush 81 is a roller-like brush in which a base cloth in which fibers such as polyester are planted is wound around a core metal, and has a width substantially equal to the width in the axial direction of the photosensitive drum 413. The lubricant application brush 81 is fixed so that the surface of the photosensitive drum 413 bites into the brush tip by a predetermined amount (for example, biting amount: 0.5 to 1.5 mm), and is opposite to the rotation of the photosensitive drum 413. Rotate (counter direction).

The solid lubricant 82 is a solidified lubricant (for example, pencil hardness: equivalent to F to HB), and is fixed to a holder (not shown) of the lubricant pressing portion 83. As the lubricant, for example, zinc stearate (ZnSt) is applied.
The lubricant pressing portion 83 has a biasing member such as a compression spring, for example, and presses the solid lubricant 82 fixed to one end side of the biasing member toward the lubricant application brush 81 with a predetermined pressing force.

  The leveling blade 84 is a flat member having a width substantially equal to the width of the photosensitive drum 413 in the axial direction. The side of the leveling blade 84 that is in sliding contact with the photosensitive drum 413 is constituted by an elastic layer 841 (see FIG. 3). The leveling blade 84 is fixed to the support member 85 and is disposed on the downstream side of the lubricant application brush 81 with respect to the rotation direction of the photosensitive drum 413. The leveling blade 84 slides with respect to the photosensitive drum 413 at a predetermined contact angle (for example, 50 °) and intrusion amount from the trailing direction (the direction in which the edge portion is dragged when the photosensitive drum 413 rotates). Touch.

  At the time of image formation, the lubricant application brush 81 rotates to scrape off the lubricant from the surface of the solid lubricant 82, and the scraped lubricant is applied to the surface of the photosensitive drum 413 at the contact point with the photosensitive drum 413. Then, the applied lubricant is leveled by the leveling blade 84 so as to have a uniform thickness.

  Further, in the present embodiment, the leveling blade 84 has a function of heating the photosensitive drum 413 at a predetermined temperature. Specifically, as shown in FIG. 3, the leveling blade 84 has a laminated structure including an elastic layer 841, a heat transfer layer 842, and a heat generation layer 843. The leveling blade 84 having a laminated structure can be produced, for example, by sheet molding or die molding.

  The elastic layer 841 is made of a material whose hardness is lower than that of the photosensitive drum 413 and is in sliding contact with the surface of the photosensitive drum 413. For the elastic layer 841, for example, a resin material such as urethane rubber or fluororubber can be used.

  The heat transfer layer 842 heats the photosensitive drum 413 through the elastic layer 841. The heat transfer layer 842 is composed of, for example, two layers of a heat insulating layer 842a and a heat storage layer 842b.

The heat insulating layer 842a is disposed on the elastic layer 841 side of the heat transfer layer 842. The heat insulating layer 842a has a thermal conductivity smaller than that of the elastic layer 841. For the heat insulating layer 842a, for example, foamed urethane, heat insulating tape, foamed ceramic, or the like can be used.
Here, the heat conductivity of the heat insulating layer 842a is preferably 0.02 to 50 W / m · k. When the thermal conductivity of the heat insulating layer 842a is less than 0.02, the heating efficiency of the photosensitive drum 413 decreases, and when the heat conductivity of the heat insulating layer 842a is larger than 50 W / m · k, heat is This is because it becomes difficult to transmit uniformly. That is, heat can be uniformly and stably transmitted to the photosensitive drum 413 by setting the thermal conductivity of the heat insulating layer 842a to 0.02 to 50 W / m · k.

Moreover, when comprising the heat insulation layer 842a with a foaming urethane or a foaming ceramic, it is preferable that a foaming rate shall be 30% or more, More preferably, it shall be 40% or more. Accordingly, when the heat insulating layer 842a is made of urethane foam, the heat conductivity of the heat insulating layer 842a is 0.02 to 50 W / m · k, so that heat can be uniformly transmitted to the photosensitive drum 413. it can. When the foaming rate is increased, the thermal conductivity is lowered and the heat insulating effect is increased.
As shown in Table 1, when the expansion ratio of the heat insulating layer 842a is less than 30%, a temperature ripple with respect to time (deviation from the target temperature) increases, and thus heat may not be uniformly transmitted to the photosensitive drum 413. There is.

  When the heat insulating layer 842a is formed of a hard material such as foam ceramic, the heat insulating layer 842a can be extended to function as the support member 85 (see FIG. 4).

The heat storage layer 842b is disposed on the heat generation layer 843 side of the heat transfer layer 842. The heat storage layer 842b has a larger heat capacity than the elastic layer 841. For the heat storage layer 842b, for example, a metal-dispersed resin obtained by dispersing a metal in a resin material such as rubber, stainless steel, or the like can be used. The heat capacity of the heat storage layer 842b can be adjusted by the type of metal to be dispersed, the amount of dispersion, the dispersion method, or the like.
Here, the heat capacity of the heat storage layer 842b is preferably larger than 100%, more preferably 150%, when the heat capacity of the urethane resin having the same mass is defined as 100%. Thereby, the photosensitive drum 413 can be efficiently heated.
As shown in Table 2, when the heat capacity is less than 100%, the temperature ripple in the length direction of the leveling blade 84 is large, and the photosensitive drum 413 may not be heated uniformly and efficiently.

  When the heat storage layer 842b is made of a hard material such as stainless steel, the heat storage layer 842b can be extended to function as the support member 85 (see FIG. 5).

  The heat generating layer 843 is laminated on the surface opposite to the laminated surface of the elastic layer 841 of the heat transfer layer 842 and is a heating source for heating the heat transfer layer 842. This eliminates the need for an external heating device, so that the photosensitive drum 413 can be efficiently heated with a very simple configuration.

  The heat generating layer 843 is formed of a resistance heating element that generates heat when energized, for example. The energization control of the heat generating layer 843 is performed such that the blade temperature (surface temperature of the elastic layer 841) is, for example, 40 ° C. to the toner heat resistance temperature. The blade temperature is detected by a thermostat or a contact temperature sensor.

  As the resistance heating element, a resistance heating resin in which a conductive filler and a high ionic conductor powder are dispersed in a heat resistant resin is suitable. As the heat-resistant resin, polyimide, polyphenylene sulfide, polyether ether ketone, or the like can be applied, and polyimide is particularly preferable from the viewpoint of excellent heat resistance. In addition, a metal material powder (for example, Ag, Cu, Al, Mg, Ni fine particles) or a carbon compound powder (for example, graphite, carbon black, carbon fiber, carbon nanotube) can be applied to the conductive filler. . As the high ion conductor powder, a high ion conductor powder in an inorganic compound such as AgI or CuI can be applied.

  As described above, the lubricant application unit 80 as the lubricant application device includes the lubricant supply unit (lubricant application brush 81) for supplying the lubricant to the surface of the image carrier (photosensitive drum 413) that is rotationally driven, and the image carrier (413). ) With respect to the rotational direction of the image carrier (413), and is in sliding contact with the surface of the image carrier (413), heating the lubricant application surface of the image carrier (413), and the image carrier (413). And a leveling blade (84) for leveling the lubricant supplied to.

According to the lubricant application unit 80, the lubricant application surface of the photosensitive drum 413 is uniformly heated at a predetermined temperature, so that the lubricant can be uniformly applied to the surface of the photosensitive drum 413. Further, unlike the lubricant application device described in Patent Document 3, the lubricant application unit 80 does not need to be provided with a drive motor or the like that drives a rotating roller as a leveling member, and thus is realized with an extremely simple configuration.
In addition, according to the image forming apparatus 1 including the lubricant application unit 80, it is possible to effectively prevent a reduction in image quality due to deterioration of the photosensitive drum 413 or the cleaning blade 91.

[Example]
In the example, in the leveling blade 84 having a laminated structure including the elastic layer 841, the heat insulating layer 842 a, the heat storage layer 843 b, and the heat generation layer 843, each layer is made of the material shown in Table 3. Then, the image quality (the presence or absence of image unevenness) after the continuous formation of 5000 standard images with a coverage of 50% was evaluated. At this time, energization control to the heat generating layer 843 was performed so that the temperature of the leveling blade 84 was 40 ° C. to the heat resistant temperature of the toner.
Further, as a comparative example, the case where a leveling blade made of only an elastic layer was used, that is, the case where the surface of the photosensitive drum 413 was not heated was evaluated in the same manner as in the example.

  As a result, no image unevenness was observed at all in Examples 1 to 5, whereas some image unevenness was observed in the comparative example although it was an acceptable level.

As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the above embodiment, and can be changed without departing from the gist thereof.
For example, the heat transfer layer 842 of the leveling blade 84 according to the embodiment may be configured by only one of the heat insulating layer 842a and the heat storage layer 842b. Further, the heating layer 843 may be omitted, and the leveling blade 84 may be configured by the elastic layer 841 and the heat transfer layer 842. In this case, a heating source (for example, a heater or a hot air generator) for heating the heat transfer layer 842 is provided in the vicinity of the leveling blade 84. Furthermore, the heat transfer layer 842 may be omitted, and the leveling blade 84 may be configured by the elastic layer 841 and the heat generation layer 843.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Image reading part 20 Operation display part 30 Image processing part 40 Image forming part 50 Paper conveyance part 60 Fixing part 80 Lubricant application part 81 Lubricant application brush 82 Solid lubricant 83 Lubricant press part 84 Leveling blade 85 Support member 90 Cleaning unit 100 Control unit 841 Elastic layer 842 Heat transfer layer 842a Heat insulation layer 842b Heat storage layer 843 Heat generation layer

Claims (8)

A lubricant supply unit for supplying a lubricant to the surface of the image carrier that is driven to rotate;
The lubricant disposed on the downstream side of the lubricant supply unit with respect to the rotation direction of the image carrier, slidingly contacting the surface of the image carrier, and being supplied to the image carrier while heating the lubricant application surface of the image carrier And a leveling blade for leveling the lubricant.   2. The lubricant application device according to claim 1, wherein the leveling blade has a laminated structure including an elastic layer in sliding contact with the surface of the image carrier.   3. The lubricant application apparatus according to claim 2, wherein the leveling blade has a heat transfer layer that is laminated on the elastic layer and that uniformly transfers heat to the image carrier through the elastic layer.   The lubricant application device according to claim 3, wherein the heat transfer layer has a heat storage layer having a larger heat capacity than the elastic layer.   5. The lubricant application device according to claim 3, wherein the heat transfer layer has a heat insulating layer laminated in contact with the elastic layer and having a thermal conductivity smaller than that of the elastic layer.   The lubricant application device according to any one of claims 2 to 5, wherein the leveling blade has a heat generation layer serving as a heating source.   The lubricant application device according to any one of claims 2 to 5, further comprising a heating unit that heats the leveling blade. An image forming unit for forming a toner image on the image carrier;
A cleaning unit that removes toner remaining on the image carrier after the transfer of the toner image with a cleaning blade;
An image forming apparatus comprising: the lubricant application device according to claim 1.

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