JP2000279863A - Liquid coating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the thickness of a liquid film formed on a moving body while reducing the contact pressure between the moving body and a residual liquid removing member. SOLUTION: A liquid coating apparatus is constituted so that a plurality of removing blades 3a, 3b, 3c being residual liquid removing members are brought into contact with a developing roller 2 on the downstream side of the contact part with a photosensitive drum 1 in its rotary direction but on the upstream side of the contact part with a coating roller 4. By this constitution, the thickness of a liquid film formed on the moving body can be stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid applying apparatus for applying a liquid to a member to be coated, and more particularly, to a moving body which moves endlessly, and a coating means for applying the liquid to the surface of the moving body. And a liquid applying apparatus for applying the liquid to the member to be applied by bringing the surface into contact with the member to be applied downstream of the applying means in the moving direction.

[0002]

2. Description of the Related Art As a liquid coating apparatus of this type, there is known a wet developing apparatus which applies a developing solution as a liquid to a latent image carrier such as a photosensitive drum in an image forming apparatus.

FIG. 10 is a schematic view showing a main part of a conventional wet developing apparatus together with a photosensitive drum as a latent image carrier of an image forming apparatus. In FIG. 10, the wet developing device includes a developing roller 2 as a moving body that moves endlessly. Further, a removing blade 3 as a residual liquid removing member for removing the developer 6 remaining on the surface of the developing roller 2
And an application roller 4 as an application unit for applying the developing solution 6 to the surface, and a coating roller 4
And a regulating blade 5 for regulating the thickness of the liquid film composed of the developer 6 above.

[0004] The developer 6 contains a transparent liquid solvent and an image forming substance such as toner dispersed in the liquid solvent.

The surface of the photosensitive drum 1 bears an electrostatic latent image by, for example, irradiating a laser by a laser writing device (not shown).

[0006] The application roller 4 rotates counterclockwise in the figure as shown in the figure, and a part thereof is immersed in the developer 6.

The developing roller 2 has at least a surface layer or a layer below the surface layer made of an elastic material such as synthetic resin, rubber, or foam, and rotates counterclockwise in the drawing. Also,
The application roller 4 and the photosensitive drum 1 are disposed so as to be in parallel with each other, and a part thereof is in contact with the application roller 4. Further, a nip is formed by abutting the photosensitive drum 1 in a region downstream of the contact portion with the application roller 4 in the rotation direction.

In the above configuration, the developing solution 6 adheres to the surface of the application roller 4 that has passed through the developing solution 6 to form a developing solution film. When the developer film passes through the contact portion between the application roller 4 and the regulating blade 5 as the application roller 4 rotates, the thickness of the developer film is regulated and thinned. Then, when passing through the contact portion between the application roller 4 and the developing roller 2, a part thereof is transferred to the developing roller 2, and further thinned on the developing roller 2.

The developing roller 2 thinned as described above
The upper developer film is applied to the photosensitive drum 1 when passing through the nip as the developing roller 2 rotates. In this nip, the image forming substance present in the developer film is:
The electrostatic latent image formed on the photosensitive drum 1 and the developing roller 2
Under the influence of the electric field formed by the potential difference between
It moves and adheres on the electrostatic latent image. On the other hand, the photosensitive drum 1
An electric field is applied between the upper non-latent image portion and the developing roller 2 such that the image forming substance in the developer film is not moved toward the non-latent image portion or is moved toward the surface of the developing roller 2. It is formed. As a result, only a small amount of the liquid solvent adheres to the non-latent image portion on the surface of the photosensitive drum 1 that has passed through the nip due to the clockwise rotation in the drawing. Further, the image forming substance and a small amount of liquid solvent adhere to the portion of the electrostatic latent image, and the electrostatic latent image is developed.

The developer film on the surface of the developing roller 2 passing through the nip includes a portion where the image forming material is consumed by the development of the electrostatic latent image and a portion where the image forming material is not consumed at all. I do. Therefore, the residual liquid film on the surface of the developing roller 2 downstream of the nip is
The thickness varies in the axial direction and in the circumferential direction of the film. In particular, when a highly viscous developer is used, the amount of gravitational diffusion of the residual liquid film on the surface of the developing roller 2 becomes extremely small, so that the variation increases.

When the residual liquid film having such a thickness variation moves to the contact portion between the developing roller 2 and the coating roller 4 with the rotation of the developing roller 2, the developing film on the coating roller 4 A liquid film is transferred onto the residual liquid film.
Then, as a result of the variation being reflected on the thickness of a new developer film formed on the surface of the developing roller 2 that has passed through the contact portion, the thickness of the new developer film becomes unstable. When the thickness of the developing solution film becomes unstable in this way, the amount of the image forming substance adhered to the electrostatic latent image becomes unstable in the nip, and density unevenness occurs in the formed image.

In view of the above, a wet type developing apparatus configured to apply the developing solution 6 to the developing roller 2 by an applying member such as an applying roller as shown in FIG. 10 applies the residual liquid film between the developing roller 2 and the applying member. Before moving to the contact portion, the developing roller 2
It is configured to be removed from the surface. For example, FIG.
In the apparatus shown in FIG. 2, the removal blade 3 removes the residual liquid film from the developing roller in the developing roller rotation direction downstream of the nip and in the developing roller rotation direction upstream of the contact portion with the coating member. It is configured to mechanically scrape from the two surfaces.

[0013]

If the removal blade 3 incompletely scrapes the residual liquid film, the developing solution remains on the surface of the developing roller 2 and the developing roller 2 and the coating roller 4 Move to the contact part. In this contact portion, a portion for transferring the developing solution film on the coating roller 4 onto the residual developing solution and a portion for directly transferring the developing film on the surface of the developing roller 2 are formed, and are formed on the surface of the developing roller 2. The thickness of the new developer film becomes unstable.

However, if the removing blade 3 is brought into strong contact with the developing roller 2, the edge of the removing blade 3 will bite into the elastically deformed surface of the developing roller 2. If the developing roller 2 is left for a long time in the state of being bitten, there is a problem that the developing roller 2 cannot be returned to the original shape even if the developing roller 2 is permanently deformed.

This problem occurs in a wet developing device as a liquid coating device, but the same problem arises, for example, in a coating roller or the like as a moving body in a coating device for coating a member to be coated. Can also occur.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce a contact pressure between a moving body and a residual liquid removing member while reducing a liquid formed on the moving body. An object of the present invention is to provide a liquid coating apparatus capable of stabilizing the thickness of a film.

[0017]

Means for Solving the Problems In order to achieve the above object, the invention of claim 1 comprises a moving body which moves endlessly, and an application means for applying a liquid to the surface of the moving body. In a liquid coating apparatus for applying the liquid to the member to be coated by bringing the member into contact with the member to be coated on the downstream side of the coating unit in the moving direction, the surface on the downstream side in the moving direction of the member to be coated is provided. A plurality of residual liquid removing members for removing liquid remaining in the moving means are provided on the upstream side in the moving direction from the coating means.

The liquid coating apparatus is configured so that liquid remaining on the surface of the moving body downstream of the member to be coated in the moving direction of the moving body is removed by a plurality of residual liquid removing members. In the liquid application device having such a configuration, the residual liquid on the moving body that cannot be completely removed by the removing member positioned at the uppermost stream in the moving direction of the moving body can be removed by the removing member positioned downstream. . This makes it possible to reliably remove the residual liquid on the moving body while reducing the contact pressure between the residual liquid removing member and the moving body as compared with the case where only one removing member is provided.

According to a second aspect of the present invention, in the liquid applying apparatus according to the first aspect, the residual liquid removing member is configured as a rotatable roller that comes into contact with the moving body, and extends in the roller axis direction. A plurality of edges twisted in the circumferential direction are provided on the peripheral surface of the roller.

In this liquid applying apparatus, the roller-shaped residual liquid removing member has a plurality of edges extending in the axial direction of the roller and twisted in the circumferential direction of the roller like a so-called wire bar. This edge abuts on the surface of the moving body in a state inclined from a direction perpendicular to the moving direction of the surface, and is a direction perpendicular to the moving direction with respect to the moving body, such as an edge of a blade-like member. The stress applied to the moving body is reduced as compared with the one that comes into contact with the moving object. In addition, the residual liquid removing member provided with a plurality of such edges sequentially slides these edges into contact with the moving body to scrape the residual liquid on the moving body. The residual liquid removing member having such a configuration has a higher removal efficiency of the residual liquid from the moving body than a member having only one edge that comes into contact with the moving body, such as a blade-shaped member.

According to a third aspect of the present invention, there is provided a moving body which moves endlessly, and a coating means for applying a liquid to the surface of the moving body, and the surface is coated on the downstream side of the coating means in the moving direction. In a liquid applying apparatus for applying the liquid to the member to be applied by contacting the member, a smoothing method for smoothing a thickness of a new liquid film formed on the surface on the downstream side in the moving direction from the applying means. A plurality of forming members are provided upstream of the member to be coated in the moving direction.

In this liquid coating apparatus, the thickness of a new liquid film formed on the moving body by the liquid application of the application means is smoothed by a plurality of smoothing members. In the liquid coating apparatus having such a configuration, even if the residual liquid is completely removed by the residual liquid removing member and the thickness of a new liquid film formed on the moving body varies, the thickness is reduced by the smoothing member. Can be used for smoothing. Further, even when the thickness of the newly formed liquid film cannot be smoothed by the smoothing member located at the most upstream in the moving direction of the moving body due to the large degree of variation in the thickness of the liquid film, the thickness of the liquid film on the downstream side is reduced. Can be surely smoothed by the smoothing member located at the position (1). Therefore, even if the contact pressure between the residual liquid removing member and the moving body is reduced, and the residual liquid is incompletely removed by the residual liquid removing member, a new liquid film formed on the moving body can be formed. The thickness can be reliably smoothed.

According to a fourth aspect of the present invention, in the liquid application apparatus of the third aspect, the smoothing member is formed as a rotatable roller in contact with the moving body, and the smoothing member is swung in the roller axis direction. The liquid in the liquid film is moved on the surface in a direction different from the moving direction by moving the liquid film or by providing an edge on the roller peripheral surface of the smoothing member. It is assumed that.

In this liquid coating apparatus, the liquid in the liquid film on the moving body is moved in a direction different from the moving direction of the moving body by swinging or the edge of the smoothing member.
The diffusion speed of the liquid on the moving body is increased as compared with the case where the moving body is moved only in the moving direction in accordance with the movement of the moving body. Thus, the efficiency of smoothing the thickness of the liquid film can be further improved.

According to a fifth aspect of the present invention, there is provided a moving body which moves endlessly, and a coating means for applying a liquid to the surface of the moving body by a rotatable roller-like member, wherein the coating means is applied to the surface in the moving direction. In a liquid coating apparatus for applying the liquid to the member to be applied by bringing the member into contact with the member to be coated on a more downstream side, a plurality of the roller members are provided, and each roller member is swung in the roller axis direction. Alternatively, by providing an edge on the roller peripheral surface of each roller-like member, the liquid remaining on the surface is attached to each roller-like member while moving in a direction different from the moving direction. A liquid is applied to the surface.

In this liquid applying apparatus, while each roller-like member moves the residual liquid on the moving body in a direction different from the moving direction of the moving body, a new liquid is applied on the moving body. Form a liquid film. In the liquid coating apparatus having such a configuration, a new liquid film is formed on the moving body while the residual liquid on the moving body is diffused by each roller-shaped member. Further, even if the residual liquid cannot be sufficiently diffused by the roller-shaped member located at the uppermost stream in the moving direction of the moving body due to the presence of a large amount of the residual liquid on the moving body, The roller-like member located on the downstream side can surely diffuse the toner. Therefore, even if the contact pressure between the residual liquid removing member and the moving body is reduced, and the residual liquid is incompletely removed by the residual liquid removing member, the residual liquid is surely diffused on the moving body. Thus, a new liquid film can be formed.

[0027] The invention of claim 6 is based on claims 1, 2, 3,
4. A liquid applying apparatus according to 4, 5 or 6, wherein the liquid applying apparatus is a developing apparatus for applying the liquid developer as the liquid to a latent image carrier of an image forming apparatus.

In this developing device, while the contact pressure between the developer carrier as the moving body and the residual solution removing member for removing the residual developer on the developer carrier is reduced, the developer carrier is A uniform thickness developer film is formed on the body.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment in which the present invention is applied to a wet developing device (hereinafter, simply referred to as a developing device) of an image forming apparatus will be described. First, the configuration and operation of an electrophotographic image forming apparatus using this developing device will be described.

FIG. 1 is a schematic structural view showing a main part of the image forming apparatus. This image forming apparatus is provided with a developing device 12 for bringing a developing roller 2 as a moving body into contact with a surface of a photosensitive drum 1 as a latent image carrier. Also,
Around the photosensitive drum, in addition to the developing device 12, a charging device (not shown), an exposure device, a transfer device, a cleaning device, and the like are provided.

The photosensitive drum 1 is driven to rotate clockwise in the figure, and the surface thereof is uniformly charged at a position facing the charging device, and then, based on image information at a position facing the exposure device. It is irradiated with light to carry an electrostatic latent image. When the electrostatic latent image passes through a contact position (developing position) of the developing device 12 with the developing roller 2, the toner in the developing solution 6 is adhered and developed.

The developer 6 used in the first embodiment is
For example, a high-concentration toner is dispersed in a carrier liquid composed of an insulating liquid such as dimethylpolysiloxane oil,
It is prepared so as to exhibit a high viscosity of 0 to 10000 [mPa · s].

When the toner image developed by the adhesion of the toner on the photosensitive drum 1 passes through a position facing the transfer device, the toner image is transferred onto a transfer sheet (not shown) conveyed to the position facing the timing at an appropriate timing. You. The transfer paper on which the toner image has been transferred in this manner is sent to a fixing device (not shown), and the toner image is fixed by the action of heat and pressure.

The developer remaining on the surface of the photosensitive drum 1 passing through the position facing the transfer device is mechanically scraped and removed by the cleaning device.

By repeating the above steps, a toner image is formed on the transfer paper.

Next, the configuration of the developing device 12 of the first embodiment will be described. As shown in FIG. 1, the developing device 12 has a developer storage tank 7 that stores the developer 6. A part of the application roller 4 as an application member that rotates counterclockwise in the figure is immersed in the developer 6 stored in the developer storage tank 7. The regulating blade 5 is in contact downstream of the contact position with the liquid 6.

A developing roller 2 having at least a surface layer or a layer below the surface layer made of an elastic material such as synthetic resin, rubber, foam, or the like, is provided with a developing device such that the developing roller 2 is parallel to the coating roller 4 and the photosensitive drum 1. 12 and rotates counterclockwise in the figure. In addition, a nip is formed by bringing a part of the nip into contact with the application roller 4 and making an area downstream of the contact portion with the application roller 4 in the rotation direction abut on the photosensitive drum 1. .

When the liquid film formed on the coating roller 4 that has passed through the developing solution 6 passes through the contact portion between the coating roller 4 and the regulating blade 5 with the rotation of the coating roller 4, the thickness of the liquid film increases. Is regulated to be thinned. And the application roller 4
When passing through a contact portion between the developing roller 2 and a part thereof, a part thereof is transferred to the developing roller 2, and further thinned on the developing roller 2.

The developing roller 2 thus made thinner
The upper liquid film is applied to the photosensitive drum 1 when passing through the nip as the developing roller 2 rotates.

The developing roller 2 has a removing blade 3a, 3b, 3c as a residual liquid removing member downstream of the nip in the rotation direction and upstream of a contact portion with the coating roller 4. Is in contact.

In the developing device 12 having the above configuration, the residual developer remaining on the developing roller 2 that cannot be completely removed by the removing blade 3a positioned at the most upstream in the rotation direction of the developing roller 2 is removed on the downstream side. It can be removed by the blade 3b. Further, the residual developer that cannot be completely removed by the removing blade 3b can be removed by the removing blade 3c. Therefore, the residual developer remaining on the developing roller 2 can be reliably removed while reducing the contact pressure between the removing blade 3 and the developing roller 2 as compared with the case where only one removing blade 3 is provided.

As described above, according to the developing device 12 of the first embodiment, the residual developing solution on the developing roller 2 can be reliably removed while the contact pressure between the removing blade 3 and the developing roller 2 is reduced. Therefore, the thickness of the developer film formed on the developing roller 2 can be stabilized while reducing the contact pressure.

FIG. 2 is a schematic view showing a modified example of the developing device of the first embodiment. As shown in the drawing, in this modified example, instead of the removing blades 3a, 3b, and 3c, removing rollers 3a-1 and 3b as residual liquid removing members are used.
-1, 3c-1 are in contact with the developing roller 2. As described above, by using a roller-like member without an edge as a residual liquid removing member instead of a blade-like member with an edge, the stress applied to the developing roller 2 is greater than when using a blade-like member. Can be reduced.

Here, suppose that these removing rollers 3a-
Even if it is necessary to form a nip at the contact portions between the developing rollers 2 and 1, 3b-1, and 3c-1, since the developing roller 2 is made of an elastic material as described above, these removing rollers can be used. It is not necessary to be composed of an elastic body. Therefore, each of the removing rollers 3a-1, 3b-1, and 3c-1 can be made of a hard material such as a metal.

In this modification, as shown in FIG.
Each of the removal rollers 3a-1, 3b-1, and 3c-1 has a sub-removal blade 3a-2 for removing the developer,
Although 3b-2 and 3c-2 are abutted, even if each sub-removal blade is strongly abutted against each removal roller, the hard removal rollers will not be permanently deformed. Therefore, the sub-removal blades 3a-2, 3b-2, and 3c are provided for the respective removal rollers 3a-1, 3b-1, and 3c-1.
-2 is strongly contacted, so that the developer adhering to each of the removing rollers can be reliably removed. When a bias is applied to each of the removing rollers, the ability to remove the developer can be further improved.

As described above, according to the present modified example, the stress applied to the developing roller 2 can be reduced as compared with the case where the blade-like member is used as the residual liquid removing member, and the life of the developing roller 2 is extended. be able to. Further, since the developing solution adhering to each removing roller can be reliably removed by each sub-removing blade, each removing roller portion having no developing solution attached thereto is brought into contact with the developing roller 2,
The efficiency of removing the residual developing solution from the developing roller 2 can be improved.

FIG. 3 is a schematic view showing another modified apparatus, and FIG. 4 is a schematic view showing a removing roller (3a-3) in this modified apparatus.
1, 3b-1, 3c-1) is a perspective view showing one of them.
As shown in the drawing, in this modified example device, a removal roller having a plurality of edges extending in the roller axis direction and twisted in the roller circumferential direction, such as a wire bar, is used as a residual liquid removing member. . The removal roller provided with such an edge, with respect to the surface of the developing roller 2,
The stress applied to the surface of the developing roller is lower than that in which the edge is abutted in a state inclined from a direction orthogonal to the rotation direction and the edge is abutted in a direction orthogonal to the rotation direction like a blade-shaped member. To reduce. Further, by rotating the removing roller, the edge of the developing roller 2 is brought into sliding contact with the developing roller 2 in order to scrape off the residual developing solution on the surface of the developing roller 2, thereby providing only one edge like a blade member. In comparison, the efficiency of removing the residual developer from the developing roller 2 is increased.

The edge of each removing roller scrapes the developing solution on the developing roller 2 while slightly transporting the developing solution toward the roller axis direction. For this reason, in the present modified example apparatus, it is desirable to dispose each removal roller so that the developer transport direction in the roller axis direction of the adjacent removal rollers is opposite. With such an arrangement, it is possible to avoid a defective removal of the residual developing solution caused by collecting the developing solution near one end of the developing roller 2.

In the present modified example, it is desirable to set the peripheral speed of each removing roller to be faster than the peripheral speed of the developing roller 2. With this setting, the efficiency of removing the residual developer can be further improved.

As described above, according to the present modified example, the stress applied to the developing roller 2 can be reduced and the developing roller
Since the efficiency of removing the residual developer from the developer can be increased, the residual developer can be reliably removed while extending the life of the developing roller 2.

Next, a second embodiment in which the present invention is applied to a developing device of an image forming apparatus will be described. FIG. 5 is a schematic diagram showing the developing device 12 together with the photosensitive drum of the image forming apparatus. In FIG. 5, reference numeral 8 denotes the application roller 4
1 shows a smoothing roller as a smoothing member for smoothing the thickness of the developing solution film formed on the developing roller 2. As shown in the drawing, in the developing device 12, the contact portion between the developing roller 2 and the photosensitive drum 1 is located downstream of the contact portion between the developing roller 2 and the coating roller 4 in the rotation direction of the developing roller. Also, smoothing rollers 8a, 8b and 8c are provided on the upstream side in the developing roller rotation direction. Application roller 4
Thus, the thickness of a new liquid film formed on the developing roller 2 is smoothed by the smoothing rollers 8a, 8b, 8c.

FIG. 6 shows these smoothing rollers 8a, 8b, 8
It is a side view which shows one of c. As shown, each of the smoothing rollers 8a, 8b, 8c has a spiral edge on its peripheral surface. The spiral edge is rotated by the smoothing roller to form the developing roller 2.
The developer in the upper developer film is moved in the axial direction of the smoothing roller. That is, in the developing device 12 according to the second embodiment, the developer in the developer film on the developing roller 2 is moved in the axial direction of the smoothing roller by the edges of the smoothing rollers 8a, 8b, 8c. are doing. In the case where a trace of a spiral edge is left on the surface of the developing roller 2 immediately after passing through the contact portion with the smoothing roller (8c in the second embodiment) located on the most downstream side, Only the smoothing roller may be a flat roller having no edge.

A regulating blade for regulating the thickness of the developing solution film on the developing roller 2 is provided downstream of the smoothing rollers 8a, 8b, 8c in the direction of rotation of the developing roller, thereby regulating the thickness. However, smoothing of the thickness is further ensured.

In the developing device 12 having the above-described structure, even if the removal of the residual liquid by the removal blade 3 becomes incomplete and the thickness of the new developer film formed on the Can be smoothed by the smoothing roller 8. Further, even if the thickness of the newly formed developer film is not sufficiently smoothed by the smoothing roller 8a located at the uppermost stream in the rotation direction of the developing roller due to the large degree of variation in the thickness of the newly formed developer film, the thickness of the newly formed developer film may be reduced. It can be smoothed by the smoothing roller 8b located on the side. Further, even when the smoothing cannot be completed by the smoothing roller 8b, the smoothing can be performed by the smoothing roller 8c located on the downstream side. Therefore, even if the contact pressure between the removing blade 3 and the developing roller 2 is reduced and the residual developing solution is incompletely removed by the removing blade 3, the thickness of the liquid film formed on the developing roller 2 can be reduced. Can be reliably smoothed.

Further, by making the developing solution move in the axial direction of the smoothing roller at the edge of the smoothing roller 8, the developing solution is turned into a flat roller having no edge and the developing solution is rotated. The diffusion speed of the developing solution on the developing roller 2 can be increased, and the efficiency of smoothing the thickness of the developing solution film can be improved as compared with the case of moving the developing solution only in the direction.

As described above, in the developing device 12 according to the second embodiment, even if the contact pressure between the removal blade 3 and the developing roller 2 is reduced, the thickness of the new developing solution film formed on the developing roller 2 is reduced. Can be reliably smoothed, so that the thickness of the developer film formed on the developing roller 2 can be stabilized while reducing the contact pressure. Further, the diffusion speed of the developing solution on the developing roller 2 can be increased as compared with the case where the developing solution is moved only in the rotating direction of the developing roller by the flat smoothing roller 8 having no edge. Can be more reliably smoothed.

In the developing device 12 according to the second embodiment, the smoothing rollers 8 are arranged so that the direction of transport of the developer in the roller axis direction of the adjacent smoothing rollers 8 is directly opposite. It is desirable to do. With this arrangement, it is possible to avoid unevenness in the thickness of the developer film caused by collecting the developer near one end of the developing roller 2.

Further, in the second embodiment, the smoothing roller 8 having a configuration in which a spiral edge is provided on the peripheral surface of the roller has been described. However, as in the case of the removing roller 3 shown in FIG.
The same effect can be obtained even if the smoothing roller 8 is formed in a wire bar shape. In any case, the developing solution on the developing roller 2 is moved in the roller axis direction. However, when the edge is formed in a spiral shape, the action of moving the developing solution in the roller axis direction is strong, and the smoothing roller 8 is moved. In the case of a wire bar configuration, the function of moving the smoothing roller in the rotation direction is enhanced.

In the second embodiment, the developing device 12 provided with a smoothing roller as a smoothing member has been described. However, like the removing member 3 in the developing device of the first embodiment, the developing device 12 has a blade-like shape. Alternatively, a roller in which a blade-shaped member is brought into contact with a smoothing roller may be provided.

Further, in the second embodiment, the developing device configured to apply the developing solution to the developing roller 2 using the applying roller 4 has been described.
For example, a part of the developing roller 2 may be immersed in the developing solution, or a spray device such as a developing solution sprayer may be provided.

FIG. 7 is a perspective view showing the smoothing rollers 8a, 8b and 8c in a modified example of the developing device 12 of the second embodiment. As shown in the figure, in this modified example device, instead of providing an edge on the roller peripheral surface of the smoothing rollers 8a, 8b, and 8c, these smoothing rollers are configured to swing in the axial direction thereof. The developing solution in a new developing solution film formed on the developing roller 2 is moved in the axial direction. In such a case, it is preferable that each smoothing roller 8 is rocked so that the smoothing rollers 8 adjacent to each other are moved in opposite directions.

Next, a third embodiment in which the present invention is applied to a developing device of an image forming apparatus will be described. FIG. 8 is a schematic diagram showing the developing device 12 together with the photosensitive drum of the image forming apparatus. In FIG. 8, each application roller 4a, 4
b, 4c and 4d have spiral edges on the peripheral surface, similarly to the smoothing roller 8 shown in FIG. 6, and the developer transport direction in the roller axis direction of the adjacent application rollers 4 Are arranged in opposite directions. However, the arrangement pitch of the edges in the roller axis direction is set small enough to hold the liquid developer between the edges.

The application rollers 4a, 4b, 4c, 4
d is urged toward the developing roller 2 by a flexible pressing member 13, and is configured to rotate as the developing roller 2 rotates.

A liquid-permeable permeable member 9 immersed in a developer 6 is in contact with each of the application rollers 4a, 4b, 4c and 4d on the opposite side of the developing roller 2, and the capillary phenomenon of the permeable member 9 is caused. Supplies the developing solution 6 to the developing roller 2.

In the above configuration, the application rollers 4a, 4a
b, 4c and 4d apply a new developing solution on the developing roller 2 while moving the remaining solution on the developing roller 2 in the axial direction of the applying roller to form a developing solution film. Then, by moving the residual developing solution on the developing roller 2 in this manner, while diffusing the residual developing solution onto the developing roller 2,
A new liquid film can be formed. Further, when a large amount of the residual developing solution is present on the developing roller 2, the residual developing solution cannot be sufficiently diffused by the application roller 4 a positioned at the uppermost stream in the rotation direction of the developing roller. However, the application rollers 4b, 4c, 4d located on the downstream side
Can be reliably diffused. Therefore, even if the contact pressure between the removing blade 3 and the developing roller 2 is reduced, and the removing of the residual developing solution by the removing blade 3 is incompletely performed, the residual developing solution is surely deposited on the developing roller 2. A new liquid film can be formed while diffusing.

As described above, according to the developing device 12 of the third embodiment, even if the contact pressure between the removing blade 3 and the developing roller 2 is reduced, the residual developing solution can be diffused onto the developing roller 2 without fail. Because a new developer film can be formed,
The thickness of the developer film formed on the developing roller 2 can be stabilized while reducing the contact pressure.

In the third embodiment, the application roller 4 is described in which the developer is moved in the axial direction of the roller by the edge of the peripheral surface of the roller. However, similar to the smoothing roller 8 of the second embodiment, Alternatively, the developer may be moved in the axial direction of the roller by swinging the application roller 4 in the axial direction.

FIG. 9 is a schematic view showing a modified example of the developing device according to the third embodiment. As shown in the figure, in this modified example, the developer tray 1 is used instead of the penetrating member 9.
By providing 0 and a pump 11, the developer 6 is supplied to each of the application rollers 4 a, 4 b, 4 c, and 4 d.

In each of the embodiments described above, the case where the present invention is applied to a developing device as a liquid coating device has been described. However, the present invention is also applicable to a paint coating device or the like as a liquid coating device.

[0070]

According to the first aspect of the present invention, the residual liquid on the moving body can be reliably removed while reducing the contact pressure between the residual liquid removing member and the moving body. There is an excellent effect that the thickness of the liquid film formed on the moving body can be stabilized while reducing the pressure.

According to the second aspect of the present invention, a member capable of reducing the stress applied to the moving body and increasing the efficiency of removing the residual liquid from the moving body, compared with the blade-like member, is provided. Because it is used as, while extending the life of the moving body than when using a blade-like member,
There is an excellent effect that the residual liquid can be reliably removed.

According to the third aspect of the present invention, even if the contact pressure between the residual liquid removing member and the movable body is reduced, the thickness of a new liquid film formed on the movable body can be reliably smoothed. Therefore, there is an excellent effect that the thickness of the liquid film formed on the moving body can be stabilized while reducing the contact pressure.

According to the fourth aspect of the present invention, the efficiency of smoothing the thickness of the liquid film is more improved than when the liquid in the liquid film on the moving body is moved only in the moving direction of the moving body. Therefore, there is an excellent effect that the thickness can be more reliably smoothed.

According to the fifth aspect of the invention, even if the contact pressure between the residual liquid removing member and the movable body is reduced, a new liquid film is formed while the residual liquid is reliably diffused on the movable body. Therefore, there is an excellent effect that the thickness of the liquid film formed on the moving body can be stabilized while reducing the contact pressure.

According to the sixth aspect of the present invention, the developing solution film having a uniform thickness is formed on the developing solution carrier while reducing the contact pressure between the developing solution carrier and the residual liquid removing member. There is an excellent effect that density unevenness of an image formed by the image forming apparatus can be reduced while extending the life of the apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a main part of an image forming apparatus using a developing device according to a first embodiment.

FIG. 2 is a schematic view showing a modified example of the developing device.

FIG. 3 is a schematic view showing another modified example of the developing device.

FIG. 4 is a perspective view showing a removing roller in the modified example device.

FIG. 5 is a schematic diagram illustrating a developing device according to a second embodiment together with a photosensitive drum of the image forming apparatus.

FIG. 6 is a side view showing a smoothing roller in the developing device.

FIG. 7 is a perspective view showing a smoothing roller in a modified example of the developing device.

FIG. 8 is a schematic diagram showing a developing device according to a third embodiment together with a photosensitive drum of the image forming apparatus.

FIG. 9 is a schematic view showing a modified example of the developing device.

FIG. 10 is a schematic diagram showing a configuration of a main part of a conventional developing device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoreceptor drum 2 developing roller 3 residual liquid removing member 4 application roller 5 regulating blade 6 developer 7 developer storage tank 8 smoothing roller 9 penetrating member 10 developer tray 11 pumping pump

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 2H074 AA03 BB02 BB42 BB60 BB72 4F040 AA07 AB13 AC01 BA14 CB03 CB11 CB21 CB33 CB36 CB40 DB18 4F042 AA03 AA10 AB00 CA01 CB05 CC02 CC07 DB41 DD02 DD04 DD18 DD09 DD16

Claims (6)

[Claims] An endless moving body, and a coating means for applying a liquid to a surface of the moving body, wherein the surface is brought into contact with a member to be coated on a downstream side of the coating means in the moving direction. A liquid applying apparatus that applies the liquid to the member to be applied, a liquid removing device that removes a liquid remaining on the surface downstream of the member to be applied in the moving direction, the liquid applying device includes a liquid removing device, A liquid application device, wherein a plurality of the liquid application devices are provided on an upstream side in a moving direction. 2. The liquid applying apparatus according to claim 1, wherein said residual liquid removing member is formed as a rotatable roller which comes into contact with said moving body, and extends in the roller axis direction and is twisted in the roller circumferential direction. A liquid application device, wherein a plurality of edges are provided on a peripheral surface of the roller. 3. A moving body which moves endlessly, and an applying means for applying a liquid to a surface of the moving body, wherein the surface is brought into contact with a member to be applied on a downstream side of the applying means in the moving direction. A liquid applying apparatus that applies the liquid to the member to be applied, a smoothing member that smoothes a thickness of a new liquid film formed on the surface downstream of the applying unit in the moving direction, A liquid coating apparatus, comprising a plurality of coating members provided upstream of the member to be coated in the moving direction. 4. A liquid applying apparatus according to claim 3, wherein said smoothing member is formed in a rotatable roller shape in contact with said moving body, and said smoothing member is swung in the roller axis direction, or A liquid coating apparatus characterized in that the liquid in the liquid film is moved on the surface in a direction different from the moving direction by providing an edge on a roller peripheral surface of the smoothing member. . 5. A moving body that moves endlessly, and an application unit that applies a liquid to the surface of the moving body by a rotatable roller-shaped member, wherein the surface is located downstream of the application unit in the moving direction. In a liquid coating apparatus for applying the liquid to the member to be applied in contact with the member to be coated, a plurality of the roller-shaped members are provided, and each roller-shaped member is swung in the axial direction of the roller, or each roller-shaped member is rotated. By providing an edge on the roller peripheral surface of the member, while moving the liquid remaining on the surface in a direction different from the moving direction, the liquid adhering to each roller-like member is moved to the surface. A liquid application device characterized by being configured to apply. 6. A liquid coating apparatus according to claim 1, wherein said liquid developer is a liquid developer applied to a latent image carrier of an image forming apparatus. A liquid application device characterized by the above-mentioned.