JPH10274910A - Cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cleaning device capable of restraining the wear and the damage of the surface of an electrostatic latent image carrier and the failure of an image caused by them and prolonging the life thereof by removing residual toner on the electrostatic latent image carrier by toner attracting action to a cleaning member by bias voltage. SOLUTION: This cleaning device 7 removes the residual toner D2 which is not primarily transferred and left on a photoreceptor 1. A cleaning roller 71 is arranged by leaving a fixed space between the photoreceptor 1 and the roller 71, and driven to be rotated in a direction a4. A bias impressing device 72 impresses the bias voltage from a power source PW6 between the photoreceptor 1 and the roller 71 in order to attract the residual toner D2 adhered on the photoreceptor 1 to the roller 71. A scraper 73 is arranged in contact with the roller 71 in such a posture that the removed toner D3 is easily guided downward in order to remove the toner D3 attracted on the roller 71 by the impressing of the bias voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a copying machine or a printer, which develops an electrostatic latent image formed on an electrostatic latent image carrier using a liquid developer. For a liquid developer for transferring the obtained visible toner image to a transfer target such as an intermediate transfer member or a recording material, and removing residual toner remaining on the electrostatic latent image carrier without being transferred to the transfer target It relates to a cleaning device.

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrophotographic copying machine or a printer, when an image is formed using a liquid developer, the surface of an electrostatic latent image carrier such as a photoconductor is generally charged. An electrostatic latent image is formed by exposing the charged area based on image information to form an electrostatic latent image, and the latent image is developed using a liquid developer containing toner and carrier liquid to form a visible toner image; Is primary-transferred to an intermediate transfer member and further secondary-transferred to a recording material such as paper, or directly transferred to a recording material and fixed. After the transfer of the toner image to the transfer target such as the intermediate transfer member or the recording material, the residual toner including the carrier liquid remaining without being transferred onto the electrostatic latent image carrier is retained. To remove this, a cleaning device is employed.

[0003] As a cleaning member provided in this type of conventional cleaning device, a contact-type cleaning member such as a cleaning blade or a rotating brush is generally employed. Such a cleaning member is provided in contact with the surface of the electrostatic latent image carrier, and the rotation of the electrostatic latent image carrier causes the carrier liquid to be removed from the electrostatic latent image carrier at a portion in contact with the cleaning member. And residual toner.

[0004]

However, in this type of cleaning device, since the cleaning member is in contact with the electrostatic latent image carrier, the surface of the electrostatic latent image carrier is worn or damaged by the contact. As a result, image defects are likely to occur, and the life of the electrostatic latent image carrier is likely to be shortened. Accordingly, the present invention develops an electrostatic latent image formed on an electrostatic latent image carrier using a liquid developer containing a toner and a carrier liquid, and transfers the obtained visible toner image to a transfer target. In the image forming apparatus, a cleaning device that removes residual toner on the electrostatic latent image carrier remaining without being transferred,
Provided is a cleaning device capable of suppressing the occurrence of abrasion and damage on the surface of the electrostatic latent image carrier and image defects due to the wear, and extending the life of the electrostatic latent image carrier as compared with a conventional cleaning device. That is the task.

[0005]

In order to solve the above-mentioned problems, the present invention develops an electrostatic latent image formed on an electrostatic latent image carrier using a liquid developer containing toner and carrier liquid. An image forming apparatus for transferring the obtained visible toner image to a transfer-receiving member, wherein the cleaning device removes residual toner on the electrostatic latent image carrier remaining without being transferred; A cleaning member that is arranged at a fixed distance from the body and is driven to rotate, and a bias voltage for suctioning residual toner on the electrostatic latent image carrier to the cleaning member is applied to the electrostatic latent image carrier. A bias applying device for applying a voltage between the cleaning member and the cleaning member; and a toner removing member disposed in contact with the cleaning member to remove toner attached to the cleaning member by applying the bias voltage. That it comprises a providing a cleaning apparatus according to claim.

According to this cleaning device, the removal of the residual toner on the electrostatic latent image carrier is performed by a toner suction operation to the cleaning member by a bias voltage applied by the bias applying device. By this toner adsorption removing action, the residual toner adhered on the electrostatic latent image carrier can be removed smoothly and reliably. The cleaning member is driven to rotate, and the toner removing member is disposed in contact with the cleaning member.
The toner is removed by the toner removing member along with the rotation of the cleaning member. Thereby, the cleaning member can maintain the residual toner suction action by the bias voltage between the cleaning member and the electrostatic latent image carrier, that is, the cleaning performance of the cleaning member, and further, the residual toner adhered on the electrostatic latent image carrier can be maintained. The effect of removing the toner can be maintained.

The cleaning member is not in contact with the electrostatic latent image carrier, but is arranged at a fixed distance from the electrostatic latent image carrier, and is provided with a bias voltage applied by the bias applying device. Therefore, unlike the conventional cleaning device in which the cleaning member is brought into contact with the electrostatic latent image carrier, the surface of the electrostatic latent image carrier is worn out. Thus, the electrostatic latent image carrier can be provided with a longer service life than a conventional cleaning device without applying any load to the electrostatic latent image carrier such as being damaged.

If the gap distance between the electrostatic latent image carrier and the cleaning member is less than 50 μm, it is difficult to manufacture this apparatus, or the aggregated toner tends to clog in this gap, and exceeds 500 μm. However, since the cleaning performance of the residual toner adhered to the electrostatic latent image carrier is likely to be reduced, it is not limited thereto.
Setting in the range of 50 μm to 500 μm can be exemplified.

If the voltage applied between the electrostatic latent image carrier and the cleaning member by the bias applying device is less than 50 V, the suction of the residual toner tends to decrease, and if it exceeds 2,000 V, discharge etc. will occur. However, the present invention is not limited to this because the problem described above is likely to occur and cleaning performance is likely to be reduced.

The cleaning member may be, for example, a roller-shaped cleaning member or a belt-shaped cleaning member stretched over a plurality of rollers. Examples of the material include a material such as a resin which has a small change in shape due to an external load. The surface roughness is preferably 10 μm (ten-point average roughness: Rz) or less, because if the surface is too rough, the residual toner easily enters the surface.

The rotation direction of the cleaning member may be the same as or opposite to the rotation direction of the electrostatic latent image carrier.
If the peripheral speed of the cleaning member is lower than the peripheral speed of the electrostatic latent image carrier, the cleaning performance of the residual toner tends to decrease, so that the peripheral speed of the electrostatic latent image carrier may be higher. desirable. Further, as a material of the toner removing member, for example, a material such as a metal, a resin, and a rubber that can evenly contact the cleaning member can be used.

In the cleaning device, the toner removing member may be arranged in contact with the cleaning member so as to guide the developer on the cleaning member below the cleaning member. By doing so, the toner on the cleaning member is guided downward and is removed, so that the toner on the cleaning member is removed smoothly.

In any case, the cleaning device may include a cleaning liquid replenishing device for replenishing the cleaning member with a cleaning liquid. By supplying the cleaning liquid to the cleaning member, the toner adhered on the cleaning member is dispersed in the cleaning liquid. Therefore, the toner removing member has an improved effect of removing the toner, and accordingly, the cleaning member Cleaning performance can be improved.

As the type of the cleaning liquid, for example, a liquid developer used in the liquid developing device of the present image forming apparatus, a carrier liquid contained in the liquid developer, and a liquid having the same effect as those can be mentioned. . When the liquid developer or the carrier liquid is employed as the cleaning liquid, the cleaning liquid after cleaning the toner on the cleaning member may be reused as the developer of the liquid developing device.

Further, in any of the cleaning apparatuses, after removing the residual toner on the electrostatic latent image carrier by the cleaning member, a liquid for recovering the remaining carrier liquid adhered to the electrostatic latent image carrier. A collection auxiliary member (such as a blade) can be arranged in contact with the electrostatic latent image carrier. The liquid recovery auxiliary member is provided in contact with the electrostatic latent image carrier at a position downstream of the residual toner removal area in the rotation direction of the electrostatic latent image carrier, and The carrier liquid on the body is collected by the liquid collection auxiliary member.

As a material of the liquid recovery auxiliary member, a material that can evenly contact the liquid recovery auxiliary member with the surface of the electrostatic latent image carrier can be adopted. In any case, in order to improve the cleaning performance, a part of the cleaning member,
In particular, the mutual contact portion between the cleaning member and the toner removing member may be provided at a position where it can be disposed in the liquid developer.

As another aspect of the cleaning device according to the present invention, the following cleaning device can be employed. This cleaning device develops an electrostatic latent image formed on an electrostatic latent image carrier using a liquid developer containing a toner and a carrier liquid, and transfers the obtained visible toner image to a transfer target. In the image forming apparatus, the cleaning device is a cleaning device that removes residual toner remaining on the electrostatic latent image carrier that has not been transferred, and is disposed at a fixed interval from the electrostatic latent image carrier and is driven to rotate. A bias voltage for suctioning residual toner on the electrostatic latent image carrier to the first cleaning member between the electrostatic latent image carrier and the first cleaning member; A first bias applying device, a second cleaning member disposed at a fixed distance from the first cleaning member and driven to rotate, and a second cleaning unit configured to remove toner on the first cleaning member from the second cleaning unit. A second bias applying device for applying a bias voltage for sucking the first cleaning member and the second cleaning member between the first cleaning member and the second cleaning member, and applying a bias voltage from the second bias applying device to the second cleaning member. A toner removing member disposed in contact with the second cleaning member to remove the attached toner.

According to this cleaning device, the residual toner on the electrostatic latent image carrier is removed by a bias voltage applied by the first bias applying device, similarly to the above-mentioned type of cleaning device. The cleaning is performed by a toner suction operation to the cleaning member. By this toner adsorption removing action, the residual toner adhered on the electrostatic latent image carrier can be removed smoothly and reliably.

The first cleaning member is driven to rotate, and the second cleaning member is arranged at a fixed distance from the first cleaning member.
Since the toner is attracted to the second cleaning member by a bias voltage applied between the cleaning member and the second cleaning member by the second bias applying device, the toner adhered on the first cleaning member is As the first cleaning member rotates, it is adsorbed and removed by the second cleaning member. Thereby, the first
The cleaning member can maintain the residual toner suction action by the bias voltage between the cleaning member and the electrostatic latent image carrier, that is, can maintain the cleaning performance of the first cleaning member, and thus the residual toner adhered to the electrostatic latent image carrier. The effect of removing can be maintained.

Further, since the second cleaning member is driven to rotate, and the toner removing member is disposed in contact with the second cleaning member, the toner adhered on the second cleaning member is removed by the second cleaning member. The toner is removed by the toner removing member along with the rotation of the cleaning member.
Thereby, the cleaning performance of the second cleaning member is maintained.

Since the first cleaning member is not brought into contact with the electrostatic latent image carrier as in the case of the above-described cleaning device, the surface of the electrostatic latent image carrier may be worn or damaged. Without applying a load to the electrostatic latent image carrier, the life of the electrostatic latent image carrier can be extended as compared with a conventional cleaning device. The gap distance and the bias voltage between the electrostatic latent image carrier and the first cleaning member and between the first cleaning member and the second cleaning member are the same as in the above-described cleaning device. The gap distance is not limited to 50μ.
For example, the bias voltage may be set in a range of 50V to 2000V.

The direction of rotation of the first cleaning member is
The rotation direction of the electrostatic latent image carrier may be the same direction or the opposite direction, and the peripheral speed of the first cleaning member is desirably higher than the peripheral speed of the electrostatic latent image carrier. Further, the rotation direction of the second cleaning member may be the same as or opposite to the rotation direction of the first cleaning member, and if the peripheral speed of the second cleaning member is lower than the peripheral speed of the first cleaning member, Since the cleaning performance on the second cleaning member is likely to deteriorate, it is preferable that the peripheral speed of the first cleaning member is higher than that.

Further, in this cleaning device, the toner removing member can be arranged in contact with the first cleaning member downstream of the area where the first cleaning member and the second cleaning member face each other in the rotation direction of the first cleaning member. The toner removing member is provided to remove toner remaining on the first cleaning member that has not been completely removed by the second cleaning member.

Thus, the toner adhered to the first cleaning member is also removed by the toner removing member with the rotation of the first cleaning member, so that the cleaning performance of the first cleaning member can be further maintained, and the electrostatic latent image can be maintained. The residual toner adhered to the image carrier can be more smoothly and reliably removed. In any case, this type of cleaning device can be provided with a cleaning liquid replenishing device for replenishing the first cleaning member with a cleaning liquid, and the cleaning liquid replenishing device further maintains the cleaning performance of the first cleaning member. it can.

In any case, after the residual toner on the electrostatic latent image carrier is removed by the first cleaning member,
A liquid recovery auxiliary member (for example, a blade) for recovering the residual carrier liquid adhered to the electrostatic latent image carrier may be arranged in contact with the electrostatic latent image carrier. The liquid recovery auxiliary member is provided in contact with the electrostatic latent image carrier at a position downstream of the residual toner removal area in the rotation direction of the electrostatic latent image carrier, and The carrier liquid on the body is collected by the liquid collection auxiliary member.

The form, material and surface roughness of the first and second cleaning members,
The material of the toner removing member, the type of the cleaning liquid, and the material of the liquid recovery auxiliary member may be the same as those provided in a cleaning device of the type described above. In any case, in order to improve the cleaning performance, all or a part of the second cleaning member, in particular, the mutual contact portion between the cleaning member and the toner removing member that comes into contact with the second cleaning member is provided at a position where it can be disposed in the liquid developer. You may.

As described above, any of the cleaning devices can suppress the occurrence of abrasion, damage, and the like on the surface of the electrostatic latent image carrier, and can have a longer service life than when the electrostatic latent image carrier is cleaned by a conventional cleaning device.

[0028]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of an image forming apparatus provided with an example of a cleaning device according to the present invention. FIG. 2 is a side view of the cleaning device shown in FIG. The image forming apparatus shown in FIG. 1 includes a photosensitive member 1, a charging charger 2, a print head 3, a liquid developing device 4, a squeeze roller 100, a primary transfer charger 5, an intermediate transfer drum 6, a cleaning device 7 according to the present invention, an eraser A lamp 8, a secondary transfer roller 9, a fixing roller 10, and the like are provided.

In this image forming apparatus, the surface of the photoconductor 1 is uniformly charged by the charging charger 2 to which a voltage is applied from the power supply PW1, and the print head 3 is charged in the charging area.
Is irradiated with laser light L based on the image data, and an electrostatic latent image corresponding to the original image is formed. The electrostatic latent image is transferred to the liquid developing device 4 with the rotation of the photosensitive member 1 in the direction a1.
Move to

The liquid developing device 4 is provided with a developing roller 41 and a high-concentration liquid developer layer forming device 42, and contains the liquid developer D. The liquid developer D is obtained by dispersing a toner in a carrier liquid. The liquid developer D formed at a high density by the high-density developer layer forming device 42 to which the bias voltage has been applied from the power supply PW2 is pumped up by the developing roller 41 rotating in the direction a2. Then, while the electrostatic latent image is held, the liquid developer D is supplied to the surface of the photoconductor 1, and the electrostatic latent image is developed by application of a developing bias voltage from the power supply PW3 to become a visible toner image D1. . At this time, a carrier liquid (not shown) adheres to the photoconductor 1 together with the visible toner image D1.

The surface of the photoreceptor 1 is on the squeeze roller 100 while holding the visible toner image D1, where most of the carrier liquid is removed, and further moves to the primary transfer portion T1. The primary transfer section T1 is provided with a primary transfer charger 5 to which a primary transfer voltage is applied from a power source PW4 to attract the visible toner image D1 to the intermediate transfer drum 6.
The toner image D <b> 1 is primarily transferred onto the intermediate transfer drum 6 at a portion facing the primary transfer charger 5. The intermediate transfer drum 6 is driven to rotate in the direction a3 in order to secondarily transfer the toner image D1 to the recording sheet S while holding the toner image D1.

The recording sheet S is supplied from a recording material supply unit (not shown) and sent to a secondary transfer unit T2 in synchronization with the toner image D1 on the intermediate transfer drum 6 by a pair of timing rollers (not shown). It is. In the secondary transfer section T2, the toner image D1 on the intermediate transfer drum 6 is secondarily transferred to the recording sheet S by the secondary transfer roller 9 to which the secondary transfer voltage is applied from the power supply PW5.

After the secondary transfer of the toner image D1, the recording sheet S
Is transported to the fixing roller 10, where the toner image D1 is fixed, and then discharged. On the other hand, on the photoconductor 1,
In the primary transfer portion T1, the toner D2 remaining without being transferred to the intermediate transfer drum 6 is held.
With the rotation in the direction, the process proceeds to the cleaning device 7 and is removed by the cleaning device 7 (details will be described later).
After that, the excess charge of the photoreceptor 1 is erased by the eraser lamp 8 to prepare for the next image formation.

The photosensitive member 1 of the image forming apparatus shown in FIG.
The positive charge may be positively charged or negatively charged depending on whether regular development or reversal development is performed. The cleaning device 7 is employed in an image forming apparatus in which the toner image D1 is firstly transferred to the intermediate transfer drum 6 and then secondarily transferred to the recording sheet S.
An intermediate transfer member of another type, such as an intermediate transfer belt, may be used instead of the intermediate transfer drum 6, and may be employed in an image forming apparatus or the like that directly transfers the toner image D1 on the photoconductor 1 to the recording sheet S. You may.

Next, the cleaning device 7 will be described with reference to FIG.
It will be described in detail with reference to FIG. Cleaning device 7 shown in FIG.
Are a cleaning roller 71, a bias applying device 72,
A scraper 73 is provided as a toner removing member. The cleaning device 7 removes the photoconductor 1 remaining without being primarily transferred to the intermediate transfer drum 6 in the primary transfer portion T1.
The upper residual toner D2 is removed.

The cleaning roller 71 includes the photosensitive members 1 and 5
They are arranged at regular intervals in the range of 0 μm to 500 μm, and are driven to rotate in the direction a4 in the drawing. The bias applying device 72 applies a bias voltage from the power supply PW6 between the photoconductor 1 and the cleaning roller 71 in order to suck the residual toner D2 adhered on the photoconductor 1 to the cleaning roller 71. This bias voltage is 50V to 2000V
Is set within the range.

The scraper 73 is disposed in contact with the cleaning roller 71 to remove the toner D3 on the cleaning roller 71 sucked by the application of the bias voltage. Note that the scraper 73 is arranged in such a position that the removed toner D3 can be easily guided below the roller 71. After the visible toner image D <b> 1 is primarily transferred onto the intermediate transfer drum 6, the toner D <b> 2 remaining without being transferred onto the photoconductor 1 adheres together with the carrier liquid C. Photoconductor 1
The toner D2 and the carrier liquid C adhered to the photosensitive member 1
With the rotation in the direction a1, the process moves to the cleaning area CL1.

Since a bias voltage is applied between the photosensitive member 1 and the cleaning roller 71 from the power source PW6 of the bias applying device 72, the bias voltage adheres to the photosensitive member 1 and a1 of the photosensitive member 1
The toner D2 arriving at the cleaning area CL1 with the rotation in the direction is sucked by the cleaning roller 71.
By this toner adsorption removing action, the residual toner D2 adhered on the photoreceptor 1 can be removed smoothly and reliably.

Since the cleaning roller 71 is driven to rotate in the a4 direction, the toner D3 attached to the cleaning roller 71 moves to the cleaning area CL2 with the rotation of the cleaning roller 71 in the a4 direction. In the cleaning area CL2, the scraper 73 disposed in contact with the cleaning roller 71 scrapes off the toner D3 attached to the cleaning roller 71. As a result, the cleaning roller 71 can maintain the function of suctioning the residual toner D2 due to the bias voltage between the photosensitive member 1, that is, maintain the cleaning performance of the cleaning roller 71, and thus remove the residual toner D2 attached to the photosensitive member 1. Effect is maintained.

The cleaning roller 71 is provided for the photosensitive member 1.
The cleaning device 7 does not apply any load to the photoconductor 1 such as the surface of the photoconductor 1 being worn or damaged, and the cleaning device 7 has a longer life than the conventional cleaning device. Can be. Next, another embodiment of the cleaning device according to the present invention will be sequentially described with reference to FIGS.

The cleaning device 7a shown in FIG.
Cleaning roller 71 of the cleaning device 7 shown in FIG.
This is a cleaning device provided with a cleaning liquid replenishing device 74 for replenishing a cleaning liquid (here, the same as the developer D). Since the cleaning liquid replenishing device 74 replenishes the cleaning roller 71 with the cleaning liquid E,
The scraper 73 can easily remove the toner D3 dispersed in the cleaning liquid E, and can improve the cleaning performance accordingly.

The cleaning device 7b shown in FIG.
Is a cleaning device in which a liquid collecting blade 75 for collecting the carrier liquid C adhered to the photoconductor 1 in the cleaning device 7a shown in FIG. Further, in this apparatus, the mutual contact portion between the cleaning roller 71 and the scraper 73 is located in the developer D stored in the apparatus case 70.

The liquid recovery blade 75 is disposed in contact with the photosensitive member 1 at a position downstream of the removal area CL1 of the residual toner D2 in the rotation direction a1 of the photosensitive member 1, and is disposed in contact with the photosensitive member 1.
After the upper residual toner D2 is removed by the cleaning roller 71, the remaining carrier liquid C adhered on the photoreceptor 1 is recovered. Further, since the contact portion between the cleaning roller 71 and the scraper 73 is in the developer D, the toner D3 on the roller 71 is easily removed.

The cleaning device 7c shown in FIG.
Cleaning roller 71a, first bias applying device 72
a, a second cleaning roller 71b, a second bias applying device 72b, and a scraper 73 are provided. This cleaning device is a development of the cleaning device shown in FIG. 2, and includes a first cleaning roller 71a and a first cleaning roller 71a.
The bias applying device 72a corresponds to the cleaning roller 71 and the bias applying device 72 in the device of FIG.

The cleaning device 7c also removes the residual toner D2 on the photosensitive member 1 that has not been primarily transferred to the intermediate transfer drum 6 in the primary transfer area T1. Cleaning roller 71b and bias applying device 72b
Works to remove the toner D3 on the cleaning roller 71a instead of the scraper 73 provided in the cleaning device 7 shown in FIG.

The cleaning roller 71a is arranged at a certain distance from the photosensitive member 1 within a range of 50 μm to 500 μm, and is driven to rotate in the direction a4 in the drawing. The bias applying device 72a is provided with a power supply PW6 for sucking residual toner D2 adhered on the photoreceptor 1 to the cleaning roller 71a.
Is applied between the photoconductor 1 and the cleaning roller 71a.

The cleaning roller 71b is arranged at a certain distance from the cleaning roller 71a in the range of 50 μm to 500 μm, and is driven to rotate in the direction a5 in the drawing. The bias applying device 72b is connected to the cleaning roller 7
The cleaning roller 71 removes the toner D3 attached on the
b, the bias voltage (5
0 V to 2000 V) for the cleaning rollers 71a, 71
Apply between b.

The scraper 73 is disposed in contact with the cleaning roller 71b to remove the toner D4 on the cleaning roller 71b sucked by the application of the bias voltage. Also when this cleaning device is employed, the residual toner D2 on the photoconductor 1 moves to the cleaning area CL1.

Since a bias voltage is applied between the photosensitive member 1 and the cleaning roller 71a from the power supply PW6,
The residual toner D2 attached to the photoconductor 1 is sucked by the cleaning roller 71a. Cleaning roller 71a
Is rotated in the a4 direction, the toner D3 attached to the cleaning roller 71a moves to the cleaning area CL2 between the cleaning rollers 71a and 71b.

Since a bias voltage is applied between the cleaning rollers 71a and 71b from the power supply PW7, the toner D3 attached to the cleaning roller 71a is sucked by the cleaning roller 71b. As a result, the cleaning roller 71a can maintain the function of suctioning the residual toner D2 due to the bias voltage between the photosensitive member 1 and the cleaning performance of the cleaning roller 71a, and thus remove the residual toner D2 attached to the photosensitive member 1. The effect is maintained.

Since the cleaning roller 71b is driven to rotate in the direction a5, the toner D4 attached to the cleaning roller 71b moves to the cleaning area CL3 with the rotation of the cleaning roller 71b in the direction a5.
In the cleaning area CL3, the scraper 73 disposed in contact with the cleaning roller 71b scrapes off the toner D4 attached to the cleaning roller 71b. Thus, the cleaning performance of the cleaning roller 71b is maintained.

The cleaning device 7c can also provide a longer life to the photosensitive member 1 than a conventional cleaning device without applying a load to the photosensitive member 1 such as abrasion or damage to the surface of the photosensitive member 1. Further, a cleaning device 7d shown in FIG. 6 is a cleaning device in which a scraper 76, a cleaning liquid replenishing device 74, and a liquid recovery blade 75 are provided in the cleaning device 7c shown in FIG. Further, in this apparatus, the mutual contact portion between the cleaning roller 71b and the scraper 73 is the developer D stored in the apparatus case 70.
Is located inside.

The scraper 76 includes the cleaning roller 7.
In the rotation direction a4 of 1a, the cleaning roller 71
The cleaning roller 71a is disposed in contact with the cleaning roller 71a downstream of the facing area CL2 between the cleaning roller 71a and the cleaning roller 71b. As a result, the remaining toner on the cleaning roller 71a that has not been removed by the toner suction removal action of the cleaning roller 71b is removed.

The cleaning liquid replenishing device 74 replenishes the cleaning roller 71a with a cleaning liquid (the same as the developer here) E. Thereby, the scraper 76,
The toner 73 can easily remove the toner D3 and the toner D4 dispersed in the cleaning liquid E, and can further maintain the cleaning performance of the cleaning rollers 71a and 71b.

Since the scraper 73 is in contact with the cleaning roller 71b in the developing solution D, the roller 71
It is easy to remove the toner D4 of b. The liquid recovery blade 75
After the residual toner D2 on the photoconductor 1 is removed by the cleaning roller 71a, the photoconductor 1 is provided in contact with the photoconductor 1 at a position downstream of the removal area CL1 of the residual toner D2 in the rotation direction a1 of the photoconductor 1. The carrier liquid C remaining on the photoconductor 1 is collected.

As described above, any of the cleaning devices 7 and 7
Also, a, 7b, 7c, and 7d can suppress the occurrence of abrasion, damage, and the like on the surface of the photoconductor 1, and can prolong the service life of the photoconductor 1 as compared with the case where the photoconductor 1 is cleaned by a conventional apparatus. Next, a performance evaluation experiment of the cleaning device shown in FIGS. 4 and 6 will be described. A comparative experiment was also conducted, and will be described together.

In the evaluation experiment 1, the cleaning device 7b shown in FIG. 4 was mounted on an image forming apparatus of the type shown in FIG.
20 (manufactured by Idemitsu Petrochemical Co., Ltd.) and a dispersion of a polyester resin toner having an average particle size of 2 μm in the liquid was used. The experimental conditions are as follows.

Toner charging Negative charging Developing method Inverting developing method Toner concentration 3% by weight Surface potential of photoconductor 1 −600 V Gap distance between photoconductor 1 and cleaning roller 71 100 μm Peripheral speed of photoconductor 1 163.5 mm / s Cleaning Peripheral speed of roller 71 327 mm / s Material of cleaning roller 71 SUS (stainless steel) Diameter of cleaning roller 71 φ20 mm Surface roughness of cleaning roller 71 (ten-point average roughness: Rz) 0.5 μm Material of scraper 73 Phosphor bronze liquid Material of recovery blade 75 Polyurethane rubber Pressing pressure of liquid recovery blade 75 (per unit length) 1 gf / cm Replenishment amount of cleaning liquid by cleaning liquid replenishing device 74 34 cc / sec Cleaning liquid Same as liquid developer D Voltage value of power supply PW2 1000V power supply PW3 voltage value 400V power supply Voltage 1000V rated Experiment 2 W6 is 1 the cleaning device 7d shown in FIG. 6
The evaluation was carried out using the same type of liquid developer as in Evaluation Experiment 1. The experimental conditions are as follows.

Toner charging Negative charging Developing method Inverting developing method Toner density 3% by weight Surface potential of photoconductor 1 −600 V Gap distance between photoconductor 1 and cleaning roller 71 a 100 μm Gap distance between cleaning rollers 71 a and 71 b 100 μm Photoconductor Peripheral speed of 1 163.5 mm / s Peripheral speed of cleaning rollers 71a and 71b 327.0 mm / s Material of cleaning rollers 71a and 71b SUS (stainless steel) Diameter of cleaning rollers 71a and 71b φ20 mm Surface roughness of cleaning rollers 71a and 71b Sa (ten-point average roughness: Rz) 0.5 μm Material of scrapers 73 and 76 Phosphor bronze Material of liquid recovery blade 75 Polyurethane rubber Pressing pressure of liquid recovery blade 75 (per unit length) 1 gf / cm Cleaning liquid supply device Cleaning fluid supply amount of 74 4 cc / sec Cleaning liquid Same as liquid developer D Voltage value of power supply PW2 1000V Voltage value of power supply PW3 400V Voltage value of power supply PW6 800V Voltage value of power supply PW7 800V Both comparative experiment 1 and comparative experiment 2 are shown in FIG. The cleaning device 7b is mounted on an image forming apparatus of the type shown in FIG. 1 and the cleaning of the photoconductor 1 is performed by the blade 75 (pressing pressure 1 gf / cm) without supplying a voltage from the power supply PW6 between the photoconductor 1 and the cleaning roller 71. ), And the comparative experiment 2 was performed under the same conditions, except that the liquid collecting blade 75 was used.
Was set at 4 gf / cm (per unit length).

The cleaning devices 7b and 7d according to the present invention
In the experimental examples according to the above, in both the evaluation experiments 1 and 2, even when the photoconductor 1 was rotated 100,000 times, the residual toner on the photoconductor 1 was not substantially wiped off. The wear of the photoreceptor 1 was 0.08 μm / 10,000 rotations. On the other hand, Comparative Examples 1 and 2 in which only the liquid recovery blade 75 to which the present invention is not applied and used for removing the residual toner on the photoconductor 1 were as follows.

COMPARATIVE EXPERIMENTAL EXAMPLE 1 When the photoconductor 1 was rotated about 1000 times, the residual toner on the photoconductor 1 was left unwiped. Comparative Experimental Example 2 Even when the photosensitive member 1 was rotated 100,000 times, no wiping of the residual toner on the photosensitive member 1 occurred, but the wear of the photosensitive member 1 was 0.8.
μm / 10,000 rotations.

As described above, in Comparative Experimental Example 1, streak-like dirt is generated on the photosensitive member 1 which causes image defects such as streak noise.
In Comparative Example 2, although no streak-like stain was generated,
Abrasion and scratching of the surface of the photoconductor 1 which shortened the life of the photoconductor 1 occurred. As described above, the cleaning device according to the present invention has a longer life than the case where the photosensitive member 1 is cleaned by the conventional cleaning device.

[0063]

According to the present invention, an electrostatic latent image formed on an electrostatic latent image carrier is developed using a liquid developer containing a toner and a carrier liquid, and the resulting visible toner image is coated. In an image forming apparatus for transferring to a transfer body, a cleaning device for removing residual toner on the electrostatic latent image carrier remaining without being transferred, wherein the surface of the electrostatic latent image carrier is worn, scratched, etc. Thus, it is possible to provide a cleaning device capable of suppressing the occurrence of image defects and having a longer service life than cleaning the electrostatic latent image carrier with a conventional cleaning device.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus including an example of a cleaning device according to the present invention.

FIG. 2 is a side view of main parts of the cleaning device shown in FIG.

FIG. 3 is a side view of a main part of the cleaning device provided with a cleaning liquid replenishing device for replenishing a cleaning member with a cleaning liquid in the cleaning device shown in FIG. 2;

FIG. 4 is a side view of a main part of the cleaning device in which the liquid recovery auxiliary member is arranged in contact with the electrostatic latent image carrier in the cleaning device shown in FIG.

5 is a main part side view showing an improved example of the cleaning device shown in FIG. 2;

6 is a side view of a main part of a cleaning device provided with another toner removing member, a cleaning liquid replenishing device, and a liquid recovery auxiliary member in the cleaning device shown in FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charger 3 Laser print head L Laser beam 4 Liquid developing device 41 Developing roller 42 High-concentration liquid developer layer forming device D Liquid developer 5 Primary transfer charger T1 Primary transfer unit T2 Secondary transfer unit 6 Intermediate transfer drum 7, 7a, 7b, 7c, 7d Cleaning device 70 Cleaning device case 71 Cleaning roller 71a First cleaning roller 71b Second cleaning roller 72 Bias applying device 72a First bias applying device 72b Second bias applying device 73, 76 Scraper 74 Cleaning liquid replenishing device 75 Liquid recovery blade 100 Squeeze roller D1, D2, D3, D4 Toner CL1, CL2, CL3 Cleaning area C Carrier liquid E Cleaning liquid 8 Eraser lamp 9 Secondary transfer roller 0 fixing roller S recording sheet PW1, PW2, PW3, PW4, PW5, PW6, P
W7 power supply

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidetoshi Miyamoto 2-3-13 Azuchicho, Chuo-ku, Osaka-shi Inside Osaka International Building Minolta Co., Ltd. (72) Toshimitsu Fujiwara 2-3-3 Azuchicho, Chuo-ku, Osaka-shi 13 Osaka International Building Minolta Co., Ltd. (72) Inventor Masaharu Kanazawa 2-3-13 Azuchicho, Chuo-ku, Osaka City Osaka International Building Minolta Co., Ltd.

Claims (8)

[Claims] An electrostatic latent image formed on an electrostatic latent image carrier is developed using a liquid developer containing a toner and a carrier liquid, and the obtained visible toner image is transferred to a transfer object. In the image forming apparatus, a cleaning device that removes residual toner remaining on the electrostatic latent image carrier that has not been transferred, and is disposed at a fixed interval from the electrostatic latent image carrier and is driven to rotate. A biasing device for applying a bias voltage for sucking residual toner on the electrostatic latent image carrier to the cleaning member between the electrostatic latent image carrier and the cleaning member; A cleaning device for removing toner adhered to the cleaning member by applying the bias voltage, the cleaning device comprising: a toner removing member disposed in contact with the cleaning member. 2. The cleaning device according to claim 1, wherein said toner removing member is disposed in contact with said cleaning member so as to guide a developer on said cleaning member below said cleaning member. 3. The cleaning device according to claim 1, further comprising a cleaning liquid replenishing device that replenishes the cleaning member with a cleaning liquid. 4. The electrostatic latent image for recovering residual carrier liquid adhering on the electrostatic latent image carrier after removing residual toner on the electrostatic latent image carrier by the cleaning member. 4. The cleaning device according to claim 1, further comprising a liquid recovery auxiliary member arranged in contact with the carrier. 5. An electrostatic latent image formed on an electrostatic latent image carrier is developed using a liquid developer containing a toner and a carrier liquid, and the obtained visible toner image is transferred to a transfer target. In the image forming apparatus, a cleaning device that removes residual toner remaining on the electrostatic latent image carrier that has not been transferred, and is disposed at a fixed interval from the electrostatic latent image carrier and is driven to rotate. A first cleaning member, and a bias voltage for suctioning residual toner on the electrostatic latent image carrier to the first cleaning member between the electrostatic latent image carrier and the first cleaning member. A first bias applying device, a second cleaning member disposed at a fixed distance from the first cleaning member and driven to rotate, and suctioning toner on the first cleaning member to the second cleaning member. Bias applying device for applying a bias voltage for applying a bias voltage between the first cleaning member and the second cleaning member, and toner adhering to the second cleaning member by applying a bias voltage from the second bias applying device And a toner removing member disposed in contact with the second cleaning member to remove the toner. 6. A toner removing member is disposed in contact with said first cleaning member downstream of a region where said first cleaning member and said second cleaning member face each other in the rotation direction of said first cleaning member. A cleaning device as described. 7. The cleaning device according to claim 5, further comprising a cleaning liquid replenishing device for replenishing the first cleaning member with a cleaning liquid. 8. The electrostatic cleaning device according to claim 1, wherein said first cleaning member removes residual toner on said electrostatic latent image carrier, and collects the remaining carrier liquid adhered on said electrostatic latent image carrier. 8. The cleaning device according to claim 5, further comprising a liquid recovery auxiliary member disposed in contact with the latent image carrier.