JPH11237790A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device which prevents the minute holes of a developer hold means from being clogged. SOLUTION: The developer hold roller 3 holds liquid developer 4 to be attached onto the surface of a photoreceptor drum 2. The developer hold roller 3 takes the liquid developer 4 out of a developer container 5 by immersing a part of its lower part in the developer container 5 storing the liquid developer 4, and by rotating. Inside the developer container 5, an ultrasonic vibrator 7 is provided for giving vibration to prevent the minute holes of the developer hold roller 3 from being clogged. The ultrasonic vibrator 7 generates the vibration during a period of time that an image is not formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for developing a high-definition image using a liquid developer.

[0002]

2. Description of the Related Art Conventionally, as an image forming apparatus using a liquid developer, toner fine particles dispersed in an insulating liquid carrier such as an aliphatic saturated hydrocarbon are coated on a dielectric surface on which an electrostatic latent image is formed. Is known which is selectively adhered to electrophoresis by electrophoresis. This type is suitable for obtaining a high-resolution image because the toner particles can be set smaller than a developing device using a powder toner. On the other hand, the aliphatic saturated hydrocarbon used as a liquid carrier has an unfavorable odor, but has a disadvantage that it is not suitable for use in offices and homes.

Therefore, an image forming apparatus using a liquid developer containing water as a main component has been proposed to solve the problem of odor and to be advantageous in terms of cost (for example, Japanese Patent Publication No. Hei.
40985). In this apparatus, a cylindrical sleeve having a large number of holes penetrating in and out is provided on a peripheral surface of a cylindrical sleeve rotatably installed by immersing a part in a conductive developer filled in a tank. The peripheral surface of the sleeve exposed to the surface is faced without contacting the rotating photoreceptor surface, and when the electrostatic latent image formed on the surface of the photoreceptor gradually approaches the sleeve, the sleeve is The electrostatic field acts and the developer held in the hole by the surface tension at the same potential as the sleeve receives the electrostatic force, and when the gap between them is narrowed, the electrostatic force is further increased, and the viscosity, surface tension,
The developer is sucked onto the surface of the photoconductor against the gravity and adheres as droplets to form a visible image on the surface of the photoconductor.

[0004]

However, in the case of the structure in which the liquid developer is held in the cylindrical sleeve having a large number of holes penetrating therethrough on the peripheral surface, foreign matters such as air bubbles and dusts are formed in the cylindrical sleeve. Clogging may occur due to clogging of the through-hole, and so-called dot omission may occur in the case of development.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an image forming apparatus capable of preventing clogging of fine holes of a developer holding unit.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a dye,
A developer holding unit having a large number of penetrating fine holes for holding a liquid developer in which a coloring component such as a pigment is dissolved or dispersed, and an electrostatic latent image forming member on which an electrostatic latent image is formed Comprising, a developer holding means holding a liquid developer in each of the micro holes approach or contact the electrostatic latent image forming member,
The present invention is based on an image forming apparatus that forms an image by selectively adhering a liquid developer on the electrostatic latent image forming member by electrostatic attraction due to an electrostatic latent image.

According to a first aspect of the present invention, in the above-described image forming apparatus, a developer container containing the liquid developer and a part of the developer holding means is immersed, and the developer container provided in the developer container. And a vibration applying means for applying vibration for suppressing clogging of the fine holes of the developer holding means.

According to the first aspect of the present invention, clogging of the fine holes of the developer holding means is suppressed by the vibration applied by the vibration applying means provided in the developer container. Therefore, a situation in which the liquid developer is not supplied to the fine holes due to foreign matter such as bubbles or dust is avoided, and the liquid developer is reliably held in the fine holes of the developer holding unit.

According to a second aspect of the present invention, in the image forming apparatus of the first aspect, the vibration imparting means is an ultrasonic vibrator provided in a developer container, and the vibration imparting means is provided when the image forming apparatus is not in an image forming mode. In the time zone, the apparatus is linked to vibration control means for driving the ultrasonic transducer to generate vibration.

According to the second aspect of the present invention, the ultrasonic vibrator as the vibration applying means drives the ultrasonic vibrator by the vibration control means to generate vibration in a time zone other than the time of image formation. This prevents extra vibration from being transmitted to the developer holding means during image formation.
Therefore, deterioration of the image is prevented.

According to a third aspect of the present invention, in the above-described image forming apparatus, a developer container containing the liquid developer, wherein the developer holding means is disposed near a liquid level of the liquid developer; A vibrating means provided in the developer container for vibrating the vicinity of the liquid level of the liquid developer to apply vibration for holding the developer in the fine holes of the developer holding means; and a liquid developer liquid in the developer container. Liquid level control means for maintaining the surface at a constant height.

According to the third aspect of the present invention, the vicinity of the liquid surface of the liquid developer is vibrated by the vibration imparting means, and the liquid surface vibrates, so that the liquid developer comes into contact with the fine holes of the developer holding means. And retained in the micropores. By applying the vibration in this way, the liquid level of the liquid developer is changed, and the amount of the liquid developer held by the developer holding means is controlled, so that the amplitude and frequency of the vibration are adjusted. By doing so, it is possible to finely control the amount of the liquid developer held by the developer holding means.

According to a fourth aspect of the present invention, in the image forming apparatus of the third aspect, after the liquid developer is selectively adhered to the electrostatic latent image forming member by electrostatic attraction due to an electrostatic latent image. And a developer removing means for removing the liquid developer remaining in the developer holding means.

According to the fourth aspect of the present invention, after the liquid developer is adhered on the electrostatic latent image forming member and the image is formed,
The liquid developer remaining in the developer holding means is removed by the developer removing means, and each time image formation is performed accurately.

According to a fifth aspect of the present invention, in the image forming apparatus of the fourth aspect, the liquid developer remaining in the developer holding unit is removed by operating the developer removing unit when the image formation is stopped. A cleaning control unit is provided for setting the developer holding unit to a state where the liquid developer is not held.

According to the fifth aspect of the present invention, when the image formation is stopped, the operation of the developer removing means is controlled by the cleaning control means, and the liquid developer remaining in the developer holding means is removed. The unit does not hold the liquid developer and enters a standby state. Therefore, when the image formation is stopped in a state where the fine holes are filled with the liquid developer, a situation in which the fine holes are clogged due to the drying of the liquid developer is avoided.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing a schematic configuration of an image forming apparatus according to the present invention. In FIG. 1, an image forming apparatus 1
A photosensitive drum 2 (OPC drum) constituting an electrostatic latent image forming member capable of holding an electrostatic latent image formed on the surface thereof; And a developer holding roller 3 which is a developer holding means having fine holes 3a (see FIG. 2) penetrating through each of the fine holes 3a.
a, the developer holding roller 3 holding the liquid developer 4 is brought close to or in contact with the photosensitive drum 2, and the liquid developer 4 charged to the opposite polarity to the electrostatic latent image is charged by the electrostatic attraction by the electrostatic latent image. An image (visible image) is formed by selectively adhering to the surface of the photosensitive drum 2.

Then, a part of the lower portion of the developer holding roller 3 is immersed in a developer container 5 containing a liquid developer 4, and the developer holding roller 3 is rotated. The liquid developer 4 is taken out from the inside 5. Further, from the position where the liquid developer 4 is taken out,
On the downstream side in the rotation direction, a scraper 6 is disposed such that the tip slides while contacting the surface of the developer holding roller 3, and the scraper 6 controls the liquid amount of the liquid developer 4 on the developer holding roller 3. It is designed to be adjusted to an appropriate amount.

In the developer container 5, there is provided an ultrasonic vibrator 7 (vibration applying means) for applying vibration for suppressing clogging of the fine holes 3a of the developer holding roller 3. The ultrasonic vibrator 7 is linked to the vibration control means 8 and is driven to generate vibration in a time zone other than the time of image formation. Therefore, no vibration is generated at the time of image formation.
Vibration is not transmitted to the image and the image is not degraded.

Around the photosensitive drum 2, in addition to the above-mentioned components, a charger 11 installed close to the photosensitive drum 2 and uniformly charging the surface, and a surface of the photosensitive drum 2 as image information. Exposure device 12 for selectively exposing based on the
A transfer roller 14 for transferring an image formed by the liquid developer 4 formed on the photosensitive drum 2 to a recording sheet 13;
A cleaning roller 15 that removes the liquid developer 4 remaining without being transferred to the photosensitive drum 3 and cleans and cleans the surface of the photosensitive drum 2 is disposed in a fixed positional relationship.

The liquid developer 4 is a liquid (eg, pure water)
And a coloring component such as a dye or a pigment dissolved or dispersed therein, and has conductivity. It is sufficient that the conductivity of the liquid developer 4 is about 10 ⁸ Ω · cm or less. The liquid developer 4 is not limited to water based on the specifications of the image forming apparatus 1, but is more preferable in consideration of environmental problems and manufacturing costs. Also dyes,
The particle size of a coloring component such as a pigment can be 0.1 μm to 1 μm, which is much smaller than a general powder developer (manufactured by grinding or the like and having a particle size of 6 μm to 10 μm). small. Thus, since the particle size of the coloring component is small,
It is suitable for high resolution image formation. The liquid developer 4
Is water-based, and it is possible to use a solution containing water as a main component.
Alternatively, it is advantageous in the industrial aspect that the material cost is low.

The photosensitive drum 2 is capable of holding an electrostatic latent image on its surface, and is made of a material whose surface has a higher wettability with respect to the liquid developer 4 than the wettability of the developer holding roller 3. Is used. However, if the wettability of the photosensitive drum 2 is too high, when the liquid developer 4 adheres, the droplets spread and the image is disturbed, so that a contact angle of about 30 to 80 ° is suitable. I have. Photoconductor drum 2
An organic photoconductor material generally used for laser printers can be used as a material for forming the photoconductor.

The developer holding roller 3 is provided for supplying an appropriate amount of the liquid developer 4 to the surface of the photosensitive drum 2, and as shown in detail in FIGS. Are formed in which a fine hole 3a is formed.

As the mesh, a mesh for high-definition screen printing can be used. A mesh having 200 lines or more per inch is suitable for forming a high-definition image. The metal mesh formed by electroforming is suitable for use as the developer holding roller 3 because it can be formed without texture, and is uniform, high definition, and has a high aperture ratio. As described above, a method of forming a mesh having fine holes by electroforming is disclosed in
This is described in detail in, for example, Japanese Patent Publication No. 20740. Copper or nickel is mainly used as a material constituting this mesh, and a mesh of 200 lines or more can be created by electroforming.

When the developer holding roller 3 formed of such a mesh is used, the liquid developer 4 for forming an image for one dot is held in each of the fine holes 3a. Therefore, the finer the pitch of the fine holes 3a of the developer holding roller 3 (mesh), the more it can be used for forming a higher definition image. Further, by adjusting the thickness of the mesh, the amount of the liquid developer 4 per dot can be adjusted. However, if the thickness of the mesh is too small, the durability is reduced and the mesh is easily broken. Therefore, it is desirable that the thickness is at least 10 μm or more in consideration of handling of the mesh.

As shown in FIG. 2B, the liquid surface of the liquid developer 4 held in the fine holes 3a of the developer holding roller 3 (mesh) has a liquid level of the developing roller 3 around the fine holes 3a. And is located below the uppermost point in the figure (at a position distant from the contact point of the photosensitive drum 2), and is held so that the liquid developer 4 does not adhere to the uppermost point portion of the surface. . This is because when the excess liquid developer 4 is scraped off by the scraper 6 (doctor blade), the liquid developer 4 is removed from the surface of the developer holding roller 3 and the liquid developer 4 remains only in the fine holes 3a. Because the liquid developer 4 is held, the liquid surface of the liquid developer 4 is located at a position farther from the surface (contact surface) due to the surface tension.

In particular, the fine holes 3a have a surface (contact surface).
Since a substantially trumpet-shaped curved surface structure in which the hole diameter increases as approaching is obtained, excess liquid developer 4 near the surface held by the fine holes 3a can be easily removed. This is because the scraper 6 easily enters the vicinity of the inside of the contact surface of the fine hole 3a due to the large hole diameter, and the angle formed by the surface of the curved surface structure with respect to the contact surface is smaller than 90 °. This is because the liquid developer 4 is removed from the fine holes 3a by the scraper 6 as large droplets along the surface of the curved surface structure by the action of the surface tension. As a result, the liquid level of the liquid developer 4 remaining in the fine holes 3 a is on the inner side than the surface of the developer holding roller 3 that comes into contact with the photosensitive drum 2. The same effect can be obtained by forming the fine holes in a tapered structure (inclined structure) in which the hole diameter increases as approaching the surface, instead of the curved surface structure having a substantially trumpet shape.

Further, the smaller the line width of the fine holes 3a with respect to the hole diameter, the more difficult it is for extra liquid droplets to adhere to the surface.
According to an experiment with the liquid developer 4 of the present embodiment, it has been confirmed that if the opening ratio is 20% or more, it is possible to remove a large amount of liquid droplets while securing a sufficient amount of liquid. .

Further, by making the surface of the developer holding roller 3 water-repellent, it is possible to make it more difficult for excess liquid developer 4 to adhere. As a means for imparting water repellency, water repellent plating such as nickel fluorine plating is suitable, and a highly stable water repellent effect can be easily obtained. Further, a water-repellent resin such as a silicone resin is
It is also possible to add water repellency by coating on the surface of.

The developer container 5 is a member for storing the liquid developer 4 and supplying it to the developer holding roller 3.
It is desirable that the portion other than the portion where the developer holding roller 3 is immersed has airtightness.

The scraper 6 includes the developer holding roller 3
The surface of the liquid developer 4 is adjusted by sliding in contact with the liquid developer 4 and can be formed using, for example, a silicone resin or the like.

As the charger 11, a scorotron charger used in an ordinary laser printer can be used, and the charging potential can be set to about 400 to 600V.

The selective exposure device 12 includes an optical scanning device composed of a semiconductor laser, a polygon scanner, and the like. The surface of the photosensitive drum 2 charged by the charger 11 is scanned by the optical scanning device. By performing modulation based on image information while scanning the surface of 2,
An electrostatic latent image is formed.

As the transfer roller 14, a rubber roller made of silicon rubber or urethane rubber can be used. In addition, the conductivity can be improved by adding carbon to these rubbers, and the transfer can be promoted by applying a bias voltage.

As the cleaning roller 15, a sponge roller that easily absorbs the liquid developer 4 is used.

Next, the principle that the liquid developer 4 selectively adheres to the electrostatic latent image formed on the photosensitive drum 2 from the developer holding roller 3 will be described with reference to FIGS. 3 (a) to 3 (c). Will be explained.

Liquid developer 4 supplied from developer container 5
As shown in FIG. 3A, the liquid level in the fine holes 3a of the grounded developer holding roller 3 (metal mesh)
It is held so that it is located inside the surface.

When the photosensitive drum 2 and the developer holding roller 3 rotate, the distance between the liquid developer 4 held in the fine holes 3a and the electrostatic latent image 21 formed on the photosensitive drum 2 gradually increases. , And as shown in FIG.
The surface of the developer holding roller 3 and the surface of the photosensitive drum 2 come into contact with each other. The distance between the liquid developer 4 and the electrostatic latent image 21 at the time of the closest approach is about several μm. This distance is
The shape of the fine holes 3a, the wettability of the liquid developer 4 with respect to the fine holes 3a, and the adjustment of the scraper 6 (for example, the scraper 6)
And the contact angle with the developer holding roller 3), and the variation between the fine holes 3a and the variation over time are small.

At this time, the liquid developer 4 in the vicinity of the area where the charge of the electrostatic latent image 21 exists is attracted by the electrostatic force and comes into contact with the surface of the photosensitive drum 2.

When the photosensitive drum 2 and the developer holding roller 3 are further rotated, the surface of the photosensitive drum 2 is made of a material having better wettability to the liquid developer 4 than the peripheral surface of the fine hole 3a. When the surface of the developer holding roller 3 separates from the surface of the photosensitive drum 2, the liquid developer 4 remains attached to the photosensitive drum 2 as shown in FIG. Remains. On the other hand, the liquid developer 4 in the vicinity of the region where no electric charge exists is not affected by the electrostatic force and remains in the micro holes 3a. in this way,
In the non-image area, the liquid developer 4 does not come into contact with the surface of the photosensitive drum 2, so that dirt and fog hardly occur.

As is clear from the above description, the liquid developer 4 held in the fine holes 3a of the developer holding roller 3
Selectively adhere to the electrostatic latent image 21 to form an image on the photosensitive drum 2.

Next, the operation of the image forming apparatus 1 will be described.

Liquid developer 4 used in image forming apparatus 1
Is stored in the developer container 5 and the developer holding roller 3
Is partially immersed in the liquid developer 4 in the developer container 5 so that the liquid developer 4
a,... and are retained. Then, as the developer holding roller 3 rotates, the liquid developer 4 is sequentially held in an appropriate amount in the fine holes 3a,.

Then, the developer holding roller 3 rotates,
By contacting the scraper 6, from its surface,
Excess liquid developer 4 is removed. Thereby, the liquid developer 4 which is separated and held in each of the fine holes 3a,.
An appropriate amount is set in each micropore 3a.

On the other hand, after the surface of the photosensitive drum 2 is uniformly charged by the charger 11, the photosensitive drum 2 is selectively exposed by the selective exposure device 12, and the electrostatic latent image 21 ( FIG. 3A is formed.

The photosensitive drum 2 and the developer holding roller 3
Means that the liquid developer 4 selectively adheres to the electrostatic latent image 21 as described above by rotating while contacting each other. Thereby, on the photosensitive drum 2,
An image is formed by the liquid developer 4.

Thereafter, the recording paper 13 is conveyed to a nip portion between the photosensitive drum 2 and the transfer roller 14 by conveying means (not shown).
The image formed by the upper liquid developer 4 is transferred to the recording paper 13,
A final image is formed on the recording paper 13. Here, recording paper 1
The liquid developer 4 remaining without being transferred to the photosensitive drum 3 is removed by the cleaning roller 15, and the surface of the photosensitive drum 2 returns to the initial state. By repeating these series of operations, a desired image is formed on the recording paper 13 and the image is fixed by a fixing unit in the image forming apparatus 1. It is discharged outside.

In a time period in which such image formation is not performed, the ultrasonic vibrator 6 is vibrating.
Due to the vibration, bubbles, dust and the like are removed from the developer holding roller 3.
Are prevented from being clogged. As a result, it is possible to avoid a situation where the liquid developer 4 is not supplied to the fine holes of the developer holding roller 3.

In particular, in a time zone other than the time of image formation,
Since the ultrasonic vibrator 6 is driven to generate the above-described vibration, it is possible to avoid transmission of extra vibration to the developer holding roller 3, prevent image deterioration, prevent air bubbles,
It is possible to prevent dust or the like from clogging the fine holes 3a of the developer holding roller 3.

In the above-described embodiment, the lower portion of the developer holding roller 3 is immersed in the developer 4 of the developer container 5, but in addition, as shown in FIGS. A developer holding roller 3A is arranged near the liquid surface of the liquid developer 4 in the container 5, and the ultrasonic vibrator 7 vibrates the liquid surface of the liquid developer 4 near the liquid surface. The liquid developer 4 may be held in the fine holes of the developer holding roller 3A. In this case, the developer container 5
The liquid level of the liquid developer 4 inside is controlled by liquid level control means (not shown).
Is constantly maintained at a constant height. For example, the liquid level control means supplies a predetermined amount of liquid developer when the liquid level changes by a sensor that detects the liquid level of the developer container 4 and a signal from the sensor. And a developer supply means for maintaining the liquid level within a predetermined range so that the liquid developer 4 can be easily held on the developer holding roller 3A by the vibration of the liquid level. Can be.

During image formation, the liquid developer 4 adheres to the surface of the photosensitive drum 2 to form an image on the developer holding roller 3A, and then the liquid developer remaining on the developer holding roller 3A is formed. A developer collecting roller 31 is provided as a developer removing unit for removing the developer 4. The developer collecting roller 31 is linked with a cleaning control unit (not shown), and the cleaning control unit
In the image formation, not only the liquid developer 4 remaining as described above is removed, but also the liquid developer 4 remaining on the developer holding roller 3A when the image formation is stopped.
Is removed, and the developer holding roller 3A is configured to stand by without holding the liquid developer. That is, at the time of image formation suspension in which the liquid level vibration caused by the vibration of the ultrasonic vibrator 7 is stopped, the developer holding roller 3A makes one rotation, so that the liquid developer 4 held in the fine holes becomes the developer collecting roller 31. When the developer holding roller 3A does not hold the liquid developer at all, the rotation of the developer holding roller 3A is stopped and the developer holding roller 3A enters a standby state.

Therefore, if the liquid developer 4 is held on the developer holding roller 3A by the liquid surface vibration as described above, unlike the above-described embodiment, the amplitude applied by the ultrasonic vibrator 7 and By adjusting the vibration characteristics such as the vibration frequency, it is possible to perform fine control on the amount of the liquid developer 4 held on the developer holding roller 3A. Further, the developer holding roller 3A is configured to remove the liquid developer 4 remaining on the developer holding roller 3A by the developer collecting roller 31 after forming an image on the photosensitive drum 2; The liquid developer 4 can be uniformly and uniformly held in the fine holes of the developer holding roller 3A, and image formation can be performed with high accuracy. In addition, when the image formation is stopped, the liquid developer 4 remaining on the developer holding roller 3A is collected and removed by the developer collecting roller 31, and the developer holding roller 3A is
Because I am waiting in a state where it does not hold at all,
It is possible to prevent the image formation from being stopped in a state where the fine holes are filled with the liquid developer 4, and to avoid a situation in which the fine holes are clogged by a coloring component or the like due to the drying of the liquid developer 4. Can be.

In the above-described embodiment, a metal mesh having no lattice is used for the developer holding roller. However, a mesh having a calendar finish for improving flatness is used. Can also. Also, the shape of the micropore is not limited to a square,
Round, oval and other shapes are acceptable.

In the above embodiment, an aqueous liquid developer is used in consideration of environmental aspects. However, the present invention is not limited to this, and the present invention is not limited thereto. It is also possible to use agents.

[0056]

The present invention is embodied in the form described above, and has the following effects.

According to the first aspect of the present invention, the developer container in which a part of the developer holding means is immersed is provided with vibration imparting means for imparting vibration for suppressing clogging of the fine holes of the developer holding means. Therefore, with a simple configuration in which vibration is applied by the vibration applying unit, foreign matter such as air bubbles and dust can be prevented from clogging the fine holes of the developer holding unit, and the liquid developer can be supplied to the developer holding unit. Can be avoided. Therefore, it is possible to reliably and uniformly hold the liquid developer in the fine holes of the developer holding unit.

According to the second aspect of the present invention, since the ultrasonic vibrator is used as the vibration applying means, the control of the vibration is simple, and the vibration control means can control the ultrasonic vibration in a time zone other than the time of image formation. Since the vibration is generated by driving the sonic vibrator, it is possible to avoid transmission of extra vibration to the developer holding means during image formation, and to prevent image deterioration.

According to a third aspect of the present invention, the vibrating means vibrates the liquid developer in the vicinity of the surface of the liquid developer so that the liquid developer is brought into contact with the fine holes of the developer holding means to hold an appropriate amount of the liquid developer. Therefore, it is possible to finely control the amount of the liquid developer held by the developer holding unit by adjusting the vibration characteristics such as the amplitude and the frequency.

According to the fourth aspect of the present invention, after an image is formed on the electrostatic latent image forming member, the liquid developer remaining in the developer holding means is removed by the developer removing means. The liquid developer can be uniformly held in the fine holes of the developer holding means, and image formation can be performed accurately.

According to a fifth aspect of the present invention, when the image formation is stopped,
Under the control of the cleaning control means, the liquid developer remaining in the developer holding means is removed, and the developer holding means stands by without holding the liquid developer. Image formation is not stopped in a state where the holes are filled, so that a situation in which the fine holes are clogged due to drying of the liquid developer can be avoided.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a schematic configuration of an image forming apparatus according to the present invention.

FIG. 2 shows a developer holding roller according to the present invention;
Is a partially enlarged view, and (b) is a sectional view.

FIGS. 3A to 3C are explanatory diagrams of the principle of selectively adhering a liquid developer.

FIG. 4 is a diagram similar to FIG. 1 for another embodiment.

FIG. 5 is an explanatory diagram of an operation according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Photoreceptor drum 3 Developer holding roller 3A Developer holding roller 4 Liquid developer 5 Developer container 6 Scraper 7 Ultrasonic vibrator 8 Vibration control means 11 Charger 12 Selective exposure device 13 Recording paper 14 Transfer roller 21 electrostatic latent image 31 developer recovery roller

Claims (5)

[Claims] 1. A developer holding means having a large number of penetrating fine holes for holding a liquid developer in which a coloring component such as a dye or a pigment is dissolved or dispersed in a liquid, and an electrostatic latent image is formed on the surface. An electrostatic latent image forming member, and a developer holding unit holding a liquid developer in each of the fine holes is brought into close proximity to or in contact with the electrostatic latent image forming member, and selectively formed by electrostatic attraction by the electrostatic latent image. An image forming apparatus for forming an image by adhering a liquid developer onto the electrostatic latent image forming member, a developer container containing the liquid developer and partially immersed in the developer holding unit An image forming apparatus comprising: a vibration applying unit provided in the developer container and configured to apply vibration for suppressing clogging of the fine holes of the developer holding unit. 2. The vibration applying means is an ultrasonic vibrator provided in a developer container, and the vibration applying means drives the ultrasonic vibrator to generate vibration during a time period other than the time of image formation. The image forming apparatus according to claim 1, wherein the image forming apparatus is linked to a vibration control unit that generates the vibration. 3. A developer holding means having a large number of penetrating fine holes for holding a liquid developer in which a coloring component such as a dye or a pigment is dissolved or dispersed in a liquid, and an electrostatic latent image is formed on the surface. An electrostatic latent image forming member, and a developer holding unit holding a liquid developer in each of the fine holes is brought into close proximity to or in contact with the electrostatic latent image forming member, and selectively formed by electrostatic attraction by the electrostatic latent image. An image forming apparatus for forming an image by adhering a liquid developer onto the electrostatic latent image forming member, wherein the liquid developer is stored and the developer holding means is disposed near a liquid level of the liquid developer A developer container provided in the developer container, a vibration imparting means for vibrating a liquid surface of the liquid developer and vibrating the fine hole of the developer holding means to hold the developer, Keep the liquid level of the liquid developer in the developer container at a certain height An image forming apparatus comprising: 4. A liquid developer remaining on the developer holding means after the liquid developer is selectively adhered to the electrostatic latent image forming member by electrostatic attraction by an electrostatic latent image. The image forming apparatus according to claim 3, further comprising a developer removing unit that performs the operation. 5. When the image formation is stopped, the liquid developer remaining in the developer holding unit is removed by operating the developer removing unit, and the developer holding unit does not hold the liquid developer. The image forming apparatus according to claim 4, further comprising a cleaning control unit.