JPH1115281A - Developer removing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer removing device capable of obtaining a stable image by surely removing an unwanted liquid developer remaining on the surface of a developer carrier or a photoreceptor. SOLUTION: A first developer removing device 70 is provided with a solution tank 71 which retains a solution 7 for accelerating the removal of a liquid developer layer and is disposed so as to dip a developing belt 55 existing on the downstream side in the rotational direction from a developing region, in the solution 7 and a vibrating part 72 for applying vibrations by ultrasonic waves to the solution 7 retained in the solution tank 71. Then, the surface of the developing belt 55 is dipped in the solution 7 vibrated by the vibrating part 72, so that the liquid developer layer remaining on the surface of the belt 55 leaves the belt 55, to be surely removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a facsimile apparatus, a printer, and the like for visualizing an electrostatic latent image by bringing a liquid developer thinly coated on a developer carrier and a photosensitive member into contact with the photosensitive member. The present invention relates to a developer removing apparatus for removing an unnecessary liquid developer adhered to the surface of a developer carrying member or a photoreceptor, particularly to improvement of image quality.

[0002]

2. Description of the Related Art In a conventional image forming apparatus, a high-concentration and high-viscosity liquid developer is applied in a thin layer to a developing belt or a developing roller as a developer carrying member. Then, in the developing area where the liquid developer layer applied to the developer carrier and the electrostatic latent image formed on the photoconductor come into contact, the liquid developer layer is transferred to the electrostatic latent image to form a toner image. doing. The toner image formed on the photoconductor is transferred to the recording medium in a transfer area where the photoconductor and the recording medium are close to each other. In addition, the image forming apparatus is provided with a cleaning blade as a developer removing device that is in contact with, for example, the surface of the developing belt downstream of the developing area, and scrapes and removes the remaining liquid developer layer that cannot move to the electrostatic latent image on the photoconductor. doing. Further, a cleaning blade is provided in contact with the surface of the photoreceptor downstream of the transfer area to scrape and remove the liquid developer layer remaining without being transferred to the recording medium.

[0003]

However, if the contact surface of the cleaning blade, which is a developing solution removing device, is damaged by, for example, dust mixed in the liquid developer layer, the developing belt is removed from the gap of the cleaning blade. Alternatively, the liquid developer flows out and remains on the surface of the photoreceptor. Then, the remaining liquid developer changes the layer thickness of the toner image with respect to the image to be formed next, which may cause image density unevenness, or the remaining liquid developer may remain as dust on the image.

The present invention has been made to solve such a problem, and a stable image can be obtained by reliably removing unnecessary liquid developer remaining on the surface of a developer carrier or a photoreceptor. An object of the present invention is to provide a developer removing device.

[0005]

SUMMARY OF THE INVENTION A developing solution removing apparatus according to the present invention visualizes an electrostatic latent image on a photoreceptor to remove unnecessary liquid developer or photoreceptor remaining on a developer carrier. A developer tank for storing a solution for facilitating the removal of the liquid developer in a developer removing device for removing unnecessary liquid developer remaining on the photoconductor by transferring the formed visible image to a recording medium; A vibrating part for applying ultrasonic vibration to the stored solution, and immersing the portion of the developer carrier or photoconductor where unnecessary liquid developer remains in the solution stored in the solution tank, and vibrating the solution. It is characterized in that unnecessary liquid developer is removed.

The above-mentioned developer removing device comprises a solution tank for storing a solution for accelerating the removal of the liquid developer, a developer carrier immersed in the solution stored in the solution tank or a liquid developer which does not require a photosensitive member. And a jet section for spraying a jet stream of a solution to a portion where the liquid remains, it is preferable to remove unnecessary liquid developer by the jet stream of the sprayed solution.

Further, the above-mentioned developer removing device has a solution carrier for holding a solution for promoting the removal of the liquid developer, and the solution carrier contains a developer carrier or a liquid developer unnecessary for the photosensitive member. Unnecessary liquid developer may be removed by wiping the spot on the surface holding the solution.

Further, the above solution is desirably silicone or ethanol.

Further, the developing solution removing device preferably includes a scraper which comes into contact with the surface of the developer carrying member or the photosensitive member after removing the unnecessary liquid developer.

[0010] The developing solution removing device preferably includes a blower for blowing hot air to the surface of the developer carrier or the photosensitive member after removing the unnecessary liquid developer.

Further, the developing solution removing device includes a scraper contacting a developer carrier or a photosensitive member surface after removing an unnecessary liquid developer, and a developer carrier after removing the unnecessary liquid developer. Alternatively, it is desirable to provide a blower that blows warm air onto the surface of the photoconductor.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A developing solution removing apparatus according to the present invention is used in an image forming apparatus such as an electrophotographic copying machine. The image forming apparatus is arranged along a rotating direction around a photosensitive member and a photosensitive member. In addition to the charging unit, the pre-wet supply unit, the exposure unit, the developing unit, and the transfer unit, a first developer removing device and a second developer removing device are provided. The charging unit uniformly charges the photoconductor. The pre-wet supply unit thinly applies the pre-wet liquid to the surface of the photoreceptor and applies it. The exposure unit forms an electrostatic latent image on the photoconductor by exposing according to the sent image data. The developing unit has a developing belt, which is a developer carrier stretched by a plurality of rollers, a developer reservoir for storing a liquid developer composed of carrier liquid and toner particles, and a liquid developer pumped out of the developer reservoir for development. And a plurality of rollers for thinning and applying the belt. Then, the toner in the liquid developer layer is transferred to the electrostatic latent image on the photoconductor in a development area where the liquid developer layer applied on the development belt and the pre-wet liquid layer applied to the photoconductor contact. Thus, a toner image is formed. The transfer unit transfers the toner image to the recording medium in a transfer area where the fed recording medium and the toner image formed on the photoconductor are close to each other.

The first developer removing device transfers an unnecessary liquid developer layer remaining on the surface of the developing belt by transferring the liquid developer layer held by the developing belt to an electrostatic latent image on a photosensitive member in a developing area. In order to remove the solution, a solution for accelerating the removal of the liquid developer is stored, and a solution tank arranged to immerse the developing belt in the rotation direction downstream from the development area in the solution, and the solution tank is ultrasonically applied to the stored solution. And a vibrating section for applying vibration. Then, by immersing the developing belt surface in the solution vibrated by the vibrating part, the liquid developer layer remaining on the developing belt surface was dissolved or released by the solution, and the dissolution or peelability was increased. The liquid developer layer is separated from the developing belt by the vibrating solution and is reliably removed.

As described above, since the unnecessary liquid developer layer remaining on the developing belt or the like is immersed in the vibrating solution stored in the solution tank, the unnecessary liquid developer layer is reliably removed from the developing belt or the like. Therefore, it is possible to reliably prevent an image defect caused by an unnecessary liquid developer layer remaining on the developing belt or the like.

In addition, instead of the vibrating section, a jet section for spraying a jet stream of the solution is provided on a portion where an unnecessary liquid developer such as a developing belt immersed in a solution stored in a solution tank remains, for example, by dissolving or dissolving with the solution. A jet stream of a solution may be sprayed on the liquid developer having enhanced releasability to separate it from the developing belt or the like and remove it.

The second developer removing device transfers the toner image formed on the surface of the photoreceptor to a recording medium in a transfer area,
In order to remove the unnecessary liquid developer layer remaining on the photoreceptor surface, for example, a solution tank that stores a solution that promotes the removal of the liquid developer and a solution carrier that is rotatably stretched by a plurality of rollers are used. With an endless belt. The belt surface at one end of the endless belt is in contact with the photoconductor downstream of the transfer region in the rotation direction, and the belt surface at the other one end is immersed in the solution stored in the solution tank. The endless belt holds the solution by immersing the belt surface that moves with the rotation in the solution stored in the solution tank. The belt surface holding the solution moves to a position where an unnecessary liquid developer layer of the photoconductor adheres with the rotation. Then, the liquid developer layer remaining on the photoreceptor is dissolved or released by the solution held on the belt surface, and the liquid developer layer with the dissolved or released property is wiped off by the sliding belt surface. Is removed.

As described above, the unnecessary liquid developer layer such as the photoreceptor is wiped off from the surface where the solution is retained by removing the unnecessary liquid developer layer, so that the unnecessary liquid developer layer is reliably removed from the photoreceptor or the like. In addition, it is possible to reliably prevent an image defect caused by an unnecessary liquid developer layer remaining on a photoconductor or the like.

Further, the developer removing device includes a scraper that contacts the surface of the developer carrier or the photosensitive member after removing the unnecessary liquid developer layer, and a developer that removes the unnecessary liquid developer layer. A blower for blowing hot air onto the surface of the carrier or the photoreceptor may be provided so that a solution or the like adhering when removing the developer is scraped off and dried and removed by the blown hot air. This suppresses a change in the layer thickness of the liquid developer layer or the like due to the supply of the liquid developer layer or the like on the remaining solution or the like, and reliably prevents an image defect due to the change in the layer thickness. be able to.

[0019]

FIG. 1 is a configuration diagram showing the configuration of an embodiment of the present invention. As shown in FIG.
Is applied to an image forming apparatus 1 such as an electrophotographic copying machine. The image forming apparatus 1 includes a photoconductor 10, a charging unit 20 arranged around the photoconductor 10 along a rotation direction, and a pre-wet supply unit. 30, an exposure unit 40,
A first developer removing device 70 and a second developer removing device 80 are provided in addition to the developing unit 50 and the transfer unit 60. The charging unit 20 uniformly charges the photoconductor 10 rotated clockwise. Pre-wet supply unit 3
In the case of 0, the prewetting liquid 3 for suppressing the high viscosity liquid developer 5 from directly contacting the photoconductor 10 is applied to the surface of the photoconductor 10 in a thin layer. The exposure unit 40 forms an electrostatic latent image on the photoconductor 10 by exposing according to image data sent from, for example, a scanner or a host device.

The developing unit 50 stores a developing belt 55 stretched by a plurality of rollers 51 to 54 so as to rotate in the direction of the arrow at substantially the same speed as the photosensitive member 10 and a liquid developer 5 composed of carrier liquid and toner particles. The developer reservoir 56 and various rollers 57 for drawing out the liquid developer 5 in the developer reservoir 56 and applying the thinned liquid developer 5 (hereinafter, referred to as a liquid developer layer) to the developing belt 55. To 59. Then, in the developing area where the five layers of the liquid developer applied on the developing belt 55 and the three layers of the pre-wet liquid applied to the photoconductor 10 are in contact with each other, the liquid developer 5 is applied to the electrostatic latent image on the photoconductor 10. A toner image is formed by transferring the toner in the layer. The transfer unit 60 includes, for example, a transport belt 61 that adsorbs and transports the recording medium, a transfer roller 62, and the like. The transfer roller 62 is formed on the photoconductor 10 by the recording medium transported by the transport belt 61 and the developing unit 50. The toner image is transferred to a recording medium in a transfer area where the toner image comes close.

The first developer removing device 70 includes a developing belt 5
By transferring the five layers of the liquid developer held by 5 to the electrostatic latent image of the photoreceptor 10 in the developing area, unnecessary liquid developer remaining on the surface of the developing belt 55 according to the non-image portion of the photoreceptor 10 and the like In order to remove the five layers, for example, as shown in FIG. 2, a solution 7 for accelerating the removal of the five layers of the liquid developer is stored, and a developing belt 55 located downstream in the rotational direction from the developing area is immersed in the solution 7. And a vibrating section 72 for applying ultrasonic vibration to the solution 7 stored in the solution tank 71. By immersing the surface of the developing belt 55 in the solution 7 vibrated by the vibrating part 72, the five layers of the liquid developer remaining on the surface of the developing belt 55 are dissolved or peeled off by the solution 7, so that the Liquid developer 5 with enhanced peelability
The layer is separated from the developing belt 55 by the vibrating solution 7 and is reliably removed.

As described above, since the five unnecessary liquid developer layers remaining on the developing belt 55 and the like are immersed in the vibrating solution 7 stored in the solution tank 71, the unnecessary liquid developer 5 is removed from the developing belt 55 and the like. Layers can be reliably removed,
It is possible to reliably prevent an image defect caused by five unnecessary liquid developer layers remaining on the developing belt 55 and the like.

In the above-described embodiment, the unnecessary layer of the liquid developer 5 is removed from the developing belt 55 by applying ultrasonic vibration to the solution 7 stored in the solution tank 71. A jet portion for spraying a jet stream of the solution 7 is provided at a position where the unnecessary layer of the liquid developer 5 such as the developing belt 55 immersed in the solution 7 is left. By spraying a jet stream of the solution 7 on the layer, the developing belt 5
Alternatively, it may be removed from 5 or the like and removed.

The second developer removing device 80 removes five unnecessary liquid developer layers remaining on the surface of the photoconductor 10 by transferring the toner image formed on the surface of the photoconductor 10 to a recording medium in a transfer area. Next, for example, as shown in FIG.
Rollers 82 to 84 that rotate little by little in the direction opposite to the rotation direction of photoconductor 10 in accordance with the number of toner image formations
And an endless belt 81 as a solution carrier rotatably stretched by various rollers 82 to 84, and a liquid developer 5.
A solution tank 71 for storing a solution 7 for promoting the removal of the layer. The belt surface at one end of the endless belt 81 is in contact with the photoconductor 10 located downstream from the transfer area in the rotation direction by a roller 82 disposed opposite to the photoconductor 10. The other belt surface at one end is a roller 8 disposed in the solution tank 71.
3 soaks in solution 7. The endless belt 81 holds the solution 7 by immersing the belt surface that moves with the rotation in the solution 7 stored in the solution tank 71. The belt surface holding the solution 7 moves to a position where the five unnecessary liquid developer layers adhere to the photoreceptor 10 with the rotation. The five layers of the liquid developer remaining on the photoreceptor 10 are enhanced in dissolution or peeling property by the solution 7 held on the belt surface, and the five layers of the liquid developer with enhanced dissolution or peeling property are fixed on the sliding belt surface. It is wiped off and reliably removed.

As described above, by providing the endless belt 81 for wiping the portion where the five layers of the unnecessary liquid developer such as the photoconductor 10 remain on the surface holding the solution 7, the unnecessary liquid developer from the photoconductor 10 and the like is provided. Because we made sure to remove 5 layers,
An image defect caused by five unnecessary liquid developer layers remaining on the photoconductor 10 or the like can be reliably prevented. Further, even if the photoconductor 10 or the like cannot be directly immersed in the solution 7 stored in the solution tank 71, for example, the solution 7 is easily supplied to a portion where the five layers of the liquid developer remain, and the unnecessary five layers of the liquid developer are removed. Can be eliminated, and the margin of mechanism design can be increased.

In the above embodiment, the endless belt 81 is immersed in the solution 7 stored in the solution tank 71 to hold the solution 7 on the belt surface. The solution 7 may be held on the belt surface by coating.

In the above embodiment, since the solution 7 is used to remove the five unnecessary liquid developer layers remaining on the photosensitive member 10 or the developing belt 55, the photosensitive member is removed after the five liquid developer layers are removed. The solution 7 remains on the developing belt 10 or the developing belt 55. Therefore, when silicon is used as the solution 7, since silicon has a high electrical insulation property, for example, a bias condition for developing the electrostatic latent image on the photoreceptor 10 by the developing belt 55 is suppressed from fluctuating. The quality of the image to be formed can be kept constant. Further, since silicon is generally used for the pre-wet liquid or the carrier liquid of the liquid developer 5, it is possible to prevent the components of each liquid from being altered due to mixing of different kinds of liquids. . When ethanol is used as the solution 7,
Since ethanol has high volatility and easily evaporates, it is possible to suppress the solution 7 from remaining on the photoreceptor 10 or the developing belt 55 after removing the remaining five layers of the liquid developer, and to maintain a constant image quality to be formed. .

In the above embodiment, the case where ethanol or silicon is used as the solution 7 has been described. However, ethanol or silicon as the solution 7 remaining on the photoreceptor 10 or the developing belt 55 may be further removed. good.

In this case, the first developer removing device 70 is the
As shown in FIG. 7, in addition to a solution tank 71 in which, for example, ethanol as the solution 7 is stored, and a vibrating section 72, a blowing section 73 for blowing hot air onto the surface of the developing belt 55 downstream of the solution tank 71 in the rotation direction is provided. Then, the blowing unit 73 is connected to the developing belt 55.
The hot air is blown against the ethanol as the solution 7 remaining on the belt to instantaneously evaporate the ethanol and remove it from the belt surface. Thereby, it is possible to suppress a change in the layer thickness due to, for example, the supply of the five layers of the liquid developer onto the remaining solution 7 as ethanol, thereby preventing an image defect due to the change in the layer thickness. .

As shown in FIG. 5, the second developing solution removing device 80 is used to contact the endless belt 81 with the photosensitive member 10 in addition to the solution tank 71 containing silicon as the solution 7 and the endless belt 81, for example. It has a scraper 74 that comes into contact with the surface of the photoconductor 10 downstream of the contact surface in the rotation direction. Then, the scraper 74 scrapes and removes the silicon as the solution 7 remaining on the photoconductor 10 on the contact surface. Further, the scraper 74 removes the liquid developer 5 that has accidentally remained when the liquid developer 5 layer is removed.
Is also removed. Thereby, for example, the supply of the five layers of the liquid developer on the silicon as the remaining solution 7 prevents the layer thickness from changing, thereby preventing an image defect due to the layer thickness change. .

In the above description, the solution 7 remaining on the photoreceptor 10 or the developing belt 55 is removed by providing one of the blower 73 and the scraper 74. For example, the first developing solution removal shown in FIG. As in the device 70, the solution tank 7
1 and a vibrating unit 72, a scraper 74 in contact with the surface of the developing belt 55 in the rotation direction downstream of the solution tank 71, and a blowing unit 73 for blowing warm air on the surface of the development belt 55 in the rotation direction downstream of the solution tank 71. May be provided. In this case, the scraper 74 scrapes and removes the solution 7 remaining on the developing belt 55 on the contact surface. The blower 73 dries the surface of the developing belt 55 by blowing warm air on the surface of the developing belt 55 from which the solution 7 has been removed by the scraper 74.

As described above, the solution 7 remaining on the developing belt 55 and the like is scraped off and removed by the scraper 74, and further, hot air is blown from the blower 73 to dry the surface of the developing belt 55 and the like. The remaining solution 7 can be reliably removed without being affected by the properties of the solution 7 remaining on the surface such as 55.

[0033]

According to the present invention, as described above, the unnecessary liquid developer layer remaining on the photoconductor or the developer carrier is immersed in a vibrated solution. Thus, an unnecessary liquid developer layer can be reliably removed from the substrate, and an image defect caused by the unnecessary liquid developer layer remaining on the photoconductor or the developer carrier can be reliably prevented.

Further, since a jet stream of the solution is blown to a portion of the photosensitive member or the developer carrying member immersed in the solution stored in the solution tank where an unnecessary liquid developer layer remains, the photosensitive member or the developer carrying member is sprayed. An unnecessary liquid developer layer can be reliably removed from the body, and an image defect caused by the unnecessary liquid developer layer remaining on the photoconductor or the developer carrier can be reliably prevented.

Further, by providing a solution carrier for wiping a portion of the photoconductor or the developer carrier on which the unnecessary liquid developer layer remains on the surface holding the solution, unnecessary liquid from the photoconductor or the developer carrier is provided. Since the developer layer is reliably removed, an image defect caused by an unnecessary liquid developer layer remaining on the photoconductor or the developer carrier can be reliably prevented.
Further, even when the photoconductor or the like cannot be directly immersed in a solution stored in a solution tank, for example, the solution can be easily supplied to a portion where the liquid developer layer remains to remove an unnecessary liquid developer layer. Therefore, the margin of the mechanism design can be increased.

Further, since silicon having a high electrical insulating property is used as the solution for promoting the removal of the liquid developer, even if the silicon which is a solution remains on the photoreceptor or the developer carrier, for example, the developer may be used. Variations in bias conditions and the like for developing the electrostatic latent image on the photoconductor by the carrier can be suppressed, and the quality of the formed image can be kept constant.

Further, since a highly volatile ethanol is used as a solution for promoting the removal of the liquid developer,
Even if ethanol, which is a solution, remains on the photoconductor or the developer carrier, the quality of an image formed by evaporation of the ethanol can be kept constant.

Further, a scraper is provided which comes into contact with the surface of the developer carrier or the photosensitive member after removing the unnecessary liquid developer, and the solution remaining on the developer carrier or the photosensitive member is scraped off at the contact surface. By doing so, it is possible to suppress a change in the layer thickness of the liquid developer or the like by supplying the liquid developer or the like onto the remaining solution, thereby preventing an image defect due to the change in the layer thickness. .

Further, a blower for blowing hot air onto the surface of the developer carrier or the photoreceptor after removing the unnecessary liquid developer is provided, so that a solution such as ethanol remaining on the developer carrier or the photoreceptor is instantaneously removed. The layer thickness of the liquid developer and the like is prevented from changing by supplying the liquid developer and the like onto the remaining solution, and the image caused by the change in the layer thickness is removed. Failure can be prevented.

Further, the solution remaining on the developer carrier or the photoreceptor is scraped off with a scraper, and warm air is blown from a blower to dry the surface of the developer carrier or the photoreceptor. The remaining solution can be reliably removed without being affected by the properties of the solution remaining on the surface of the carrier or the photoreceptor.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a schematic diagram of a first developer removing device of the embodiment.

FIG. 3 is a schematic diagram of a second developer removing device of the embodiment.

FIG. 4 is a schematic diagram when a blower is provided in the first developer removing device.

FIG. 5 is a schematic diagram in the case where a scraper is provided in the second developer removing device.

FIG. 6 is a schematic diagram in a case where a blower and a scraper are provided in the first developer removing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Photoreceptor 20 Charging unit 30 Prewet supply unit 40 Exposure unit 5 Liquid developer 50 Developing unit 55 Developing belt 60 Transfer unit 7 Solution 70 First developer removing device 71 Solution tank 72 Vibrating part

Claims (8)

[Claims] An electrostatic latent image on a photoconductor is visualized to transfer unnecessary liquid developer remaining on a developer carrier or a visible image formed on the photoconductor to a recording medium. In a developer removing device for removing unnecessary liquid developer remaining on the body, a solution tank for storing a solution for promoting the removal of the liquid developer, and a vibrating section for applying ultrasonic vibration to the solution stored in the solution tank. Developing characterized by immersing a portion of the developer carrier or the photoreceptor where the unnecessary liquid developer remains in a solution stored in a solution tank, and removing the unnecessary liquid developer with a vibrating solution. Liquid removal device. 2. The liquid developer removing device according to claim 1, wherein the liquid developer contains a solution for facilitating the removal of the liquid developer, a developer carrier immersed in the solution stored in the solution tank, or a liquid developer that does not require the photosensitive member. 2. A developer removing device according to claim 1, further comprising: a jet section for spraying a jet stream of the solution to a portion where the liquid remains, and removing unnecessary liquid developer by the jet stream of the sprayed solution. 3. The developer removing device has a solution carrier for holding a solution for promoting the removal of the liquid developer, and the solution carrier has a developer carrier or an unnecessary liquid developer remaining on the photoconductor. 2. The developing solution removing device according to claim 1, wherein the removed portion is wiped with a surface holding the solution. 4. The method of claim 1, wherein said solution is silicone.
4. The developer removing device according to 2 or 3. 5. The method according to claim 1, wherein said solution is ethanol.
4. The developer removing device according to 2 or 3. 6. The developing solution removing device according to claim 4, wherein the developing solution removing device includes a scraper that comes into contact with the surface of the developer carrying member or the surface of the photosensitive member after removing an unnecessary liquid developer. 7. The developing solution removing device according to claim 5, wherein the developing solution removing device includes a blower for blowing warm air to a surface of the developer carrier or the photosensitive member after removing an unnecessary liquid developer. 8. The developer removing device according to claim 1, wherein the developer removing device removes an unnecessary liquid developer, and a scraper contacting a surface of the photoconductor, and a developer carrying device after removing the unnecessary liquid developer. 6. The developing solution removing device according to claim 4, further comprising: a blower that blows warm air onto the surface of the photoconductor.