JP3329178B2 - Wet developing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises an ink carrier which holds colored ink on the surface and transports the colored ink to a position close to a latent image support on which a latent image is formed on the surface. A wet developing device for developing the latent image by attaching the colored ink transported by the ink transport carrier to a latent image support surface in a pattern corresponding to the pattern of the latent image formed on the latent image support surface About.

[0002]

2. Description of the Related Art Electrostatographic image forming apparatuses have been widely used in, for example, copying machines and printers. In the electrophotographic image forming apparatus, an electrostatic latent image is formed, and the electrostatic latent image is developed to obtain a visible image. The developing method for developing the electrostatic latent image is roughly classified. A dry development method using a powder toner and a wet development method using a liquid developer are known.

Conventionally, as a wet development method, for example, a liquid developer in which a toner composed of a resin and a pigment is dispersed in an insulating carrier liquid composed of a petroleum organic solvent is used to support a latent image on which an electrostatic latent image is formed. The electrostatic latent image formed on the latent image support is developed by electrophoresis of the toner charged in the insulating carrier liquid and supplied between the body surface and a counter electrode arranged at a small interval. The method is general.

[0004] However, this wet development method is not environmentally preferable because the vapor of the petroleum organic solvent used as the insulating carrier liquid is generated. Therefore, as a wet developing method with less environmental problems, a wet developing method in which development is performed using an aqueous colored ink is proposed in US Pat. No. 4,202,620.

The wet developing method proposed in this publication is basically an electrophotographic method, in which a latent image support on which an electrostatic latent image is formed is charged by a charger to perform image exposure. When an electrostatic latent image is formed on a latent image support by using the method described above, and then the electrostatic latent image is developed, this wet developing method is applied. FIG.
FIG. 3 is a schematic view showing an outline of a development process by the proposed wet development method.

In this wet developing method, a thin layer of an aqueous colored ink 12 is formed on an ink carrier 11 having a smooth surface, and the thin layer is formed on a latent image support 13 on which an electrostatic latent image 10 is formed.
To the latent image support 1 so as not to contact the latent image support 1.
As a result, an electric field (referred to as a developing electric field) is formed between the electrostatic latent image 10 and the ink carrier 11. The developing electric field causes dielectric polarization in the case of an insulating ink and electrostatic induction in the case of a conductive ink. Due to the dielectric polarization or the electrostatic induction, a charge having a polarity opposite to that of the electrostatic latent image charge is generated in the colored ink 12. Of the colored ink 12 due to the Coulomb force of the electrostatic latent image charge induced on the surface of the colored ink and the charge induced on the surface of the colored ink.
Adheres to the image portion (portion carrying electric charges) of the electrostatic latent image 10.

The water-based ink is obtained by dispersing a dye or a pigment as a coloring component in water as a carrier liquid and conductive water as an aqueous carrier. At the moment when the aqueous ink is brought into contact with the aqueous ink 10, the latent image charge is neutralized, and the principle of the above-mentioned wet developing method of electrophoresing and developing a coloring component in the aqueous ink cannot be applied. In the case of (1), the aqueous ink 12 and the electrostatic latent image 10 are not in contact with each other, and the development is performed by bringing the colored ink 12 into contact only with the image portion by the developing electric field. Can be formed.

However, in this wet developing method, the developing electric field is concentrated on the protrusions of the colored ink 12 due to minute fluctuations on the free surface of the thin film of the colored ink 12, as schematically shown in FIG. However, in a solid image area which is a uniform image portion of the electrostatic latent image 10, the occurrence of projections is biased,
There is a problem that a uniform solid image is not formed and image omission occurs. Further, a projection is once generated in the coloring ink 12,
When the electric field is concentrated there and the protrusions further grow, the electric field is further concentrated there, and the ink is biased due to the growth of the protrusions. There is a problem in that the electrostatic latent image portion cannot be reproduced and a thin line is broken or an image is missing.

Further, when the projections of the ink adhere to the latent image support 13 to form the pillars of the ink, the ink on the ink carrier 11 is transferred to the latent image support 1 by the surface tension of the ink.
There is also a problem that a large amount of the image is moved to the third side and the image is crushed. In order to solve these problems, various methods have been proposed in which the color ink is independently held on the ink carrier 11 by a very small amount in accordance with the required resolution.

[0010] Japanese Patent Publication No. 46-41349 and Japanese Unexamined Patent Publication No.
Japanese Patent Application Publication No. 209467 discloses a method in which a fine pattern of a hydrophilic portion and a hydrophobic portion is formed on the surface of an ink carrier, and aqueous ink droplets are retained only in the hydrophilic portion by applying the wettability of a liquid. Proposed. In addition, Shoko 4
In Japanese Patent Publication No. 0-18993, Japanese Patent Publication No. 54-24517, and Japanese Patent Publication No. 57-7436, grooves, irregularities or fine holes are formed on the surface of an ink carrier, and colored ink is held in those concave parts and holes. A method has been proposed.

[0011]

In the case of a method of forming a fine pattern of a hydrophilic portion and a hydrophobic portion on the surface of an ink carrier, it is possible to finely form a pattern composed of a hydrophilic portion and a hydrophobic portion. However, even if a large difference in the contact angle between the hydrophilic portion and the hydrophobic portion with respect to the ink can be formed, as the pattern becomes finer, the adjacent ink droplets are easily connected by the surface tension, and the large ink droplet becomes large. Therefore, it is difficult to keep ink droplets finely and independently only by wettability.

FIG. 9 is a graph showing the intensity of the electric field required for development with respect to the diameter of the ink droplet on the ink carrier, and FIG. 10 is a graph showing the ink droplet on the latent image support after development with respect to the diameter of the ink droplet on the ink carrier. It is a figure which shows a diameter. As shown in FIG. 9, the larger the ink droplet on the ink carrier is, the higher the developability is. Therefore, the larger ink droplet is developed before the minute ink droplet, and as shown in FIG. The larger the ink droplet on the carrier, the larger the ink droplet after development. Therefore, if a large ink droplet is formed on the ink carrier, the image is crushed and the resolution is degraded.

In the case of a method of forming a pattern of a hydrophilic portion and a hydrophobic portion on the surface of an ink carrier, an unnecessary ink attached to the hydrophobic portion may be removed by blowing air or scraping with a roll or a blade. Then
There is also a problem that the ink in the hydrophilic portion is also removed or thinned at the same time, and the developability is reduced. On the other hand, in the case of using an ink carrier having grooves, irregularities or fine holes as ink holding portions on the surface, the size and pitch of the ink holding portions determine the resolution of the output image, so that high image quality and high image quality can be achieved. In order to increase the resolution, the size and pitch of the ink holding section must be extremely fine.

However, when the size and pitch of the ink holding unit are reduced, it is technically difficult to supply ink to the ink holding unit and to remove unnecessary ink attached to portions other than the ink holding unit. However, there is a problem that the ink held in the ink holding unit is connected to form a coarse ink droplet, or that the ink cannot be sufficiently supplied to and held in the ink holding unit, resulting in a supply omission.

Further, as the size and pitch of the ink holding unit are made finer, the manufacturing cost increases. Further, in this system, the ink is supplied to the ink holding unit and the ink adheres to parts other than the ink holding unit. In order to remove unnecessary ink, pressure contact means such as roll members and blades are required,
Due to the frictional sliding, the surface of the ink carrier is gradually shaved, and the shape of the ink holding portion is deformed and gradually collapsed. The durability of the ink carrier having the finer ink holding portion is reduced and the cost is large. It becomes a problem. further,
Due to processing technology, there is a limit to miniaturization of the size and pitch of the ink holding unit, and it is very difficult to achieve high resolution.

As one of the wet developing methods which can use aqueous inks, a method in which fine solid particles are arranged on the surface of an ink carrier and fixed all over the surface is disclosed in
No. 7436. FIG. 11 is a schematic diagram showing an outline of the wet developing method disclosed in this publication.
In the wet development method, as shown in FIG. 8, fine solid particles 14 are arranged and fixed on one surface of an ink carrier 11 so that the latent image support of the solid particles 14 is formed on the ink carrier 11. This method is intended to form projections arranged at a fine pitch consisting of vertices close to the body 13 and to generate projections of the coloring ink from each of the projections arranged at the fine pitch.

However, in practice, the ink carrier 1
Since the colored inks 12 held on 1 are not independent but are connected to each other, the electric field concentrates on the projections of the ink which is generated first, and the growth of the projections at that portion results in the surroundings. The colored ink is drawn in by the surface tension, and the ink is biased toward the first generated protrusion, and the protrusion of the colored ink hardly occurs around the protrusion, which will be described with reference to FIG. When the protrusions of the colored ink adhere to the latent image support 1 to form the ink pillars as in the conventional example described above, a large amount of ink on the ink carrier 11 due to the surface tension of the ink causes the latent image support 13 , Causing image omission and image collapse, making it impossible to achieve uniform solid phenomena and high-definition development.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and enables the use of water-based ink, and forms a high-quality image without image omission and image collapse. It is an object of the present invention to provide an inexpensive wet-type developing device that can be used.

[0019]

In order to achieve the above object, a wet developing apparatus according to the present invention holds a colored ink on the surface, and transfers the colored ink to a latent image support on which a latent image is formed on the surface. Ink carrier that is transported to the set position, and attaches the colored ink transported by the ink carrier to the latent image support surface in a pattern corresponding to the pattern of the latent image formed on the latent image support surface. In a wet developing device for developing the latent image by the above, the ink transport carrier,
A large number of aggregates, each of which is an aggregate of a plurality of particles fixed to the surface of the ink carrier, and in which a colored ink is separated in each aggregate in a space between particles of the aggregate. It is characterized by having.

Here, in the wet developing apparatus of the present invention, unnecessary ink removal for removing colored ink attached to a portion other than the interparticle gap portion of the assembly, which is disposed at a position separated from the ink transporting carrier. Preferably, it comprises a device. In the wet developing device of the present invention, it is preferable that the surface of the ink carrier is ink-repellent.

When a liquid comes into contact with a solid having voids and holes, it has the property of penetrating and retaining the voids and holes by wetting and capillary action. According to the present invention, since an aggregate of a plurality of particles is provided with an ink carrier having a large number fixed to the surface, when the colored ink is supplied to the ink carrier, the colored ink is wetted with the particles and a capillary phenomenon. As a result, the pores are naturally penetrated into the gaps between the particles formed by the adjacent particles to fill the gaps. That is, the gap between the particles serves as a holding portion for the colored ink.

What is important at this time is that the air existing in the interparticle space is not sealed when the colored ink permeates, and can easily escape to the outside. Therefore, unlike the related art, the supply of the ink to the ink holding unit is performed very smoothly, and the ink supply loss is prevented. Also, the coloring ink that has once permeated into the gap is held in the gap,
It does not flow out spontaneously, and depends on the wettability of the particle surface with the coloring ink, the size of the voids, and the surface tension and viscosity of the coloring ink, but the coloring retained in the voids even if some external force is applied No ink spill occurs.

That is, even if the colored ink remains on the surface of the ink carrier where the aggregate of particles is not fixed, the unnecessary ink is removed by blowing air or a reverse roll, or a blade or roll. To remove unnecessary ink. In particular, air blowing method, reverse roll method, etc.
When unnecessary ink is removed using a non-contact unnecessary ink removing device, the durability of the ink carrier is greatly improved because the ink carrier does not undergo any frictional sliding.
If the surface of the ink carrier is ink-repellent to the color ink to be used, the color ink is less likely to adhere to the surface of the ink carrier where the aggregate of particles is not fixed, and If the property is very high (if the contact angle with the used color ink is, for example, 100 degrees or more), the color ink hardly adheres and remains on the portion where there is no aggregate of particles, so that the removal of the unnecessary ink is very small. It will be easier.

Accordingly, it is possible to very easily hold the colored ink only in the ink holding portion on the ink carrier, that is, only in the portion where the aggregate of particles is fixed. By making each of the aggregates independent as a pattern of the aggregate of the particles, the colored ink can be held independently by an arbitrary amount. Therefore, even when developing a uniform solid image area of an electrostatic latent image, ink projections due to the developing electric field are generated in each of the aggregates of particles independent of each other, and are also held in adjacent aggregates. Even if the colored ink forms projections and the projections in that portion grow, the coloring inks are independent of each other, so that the ink is not biased. And a uniform solid image without omission can be formed.

In addition, even with respect to fine image portions such as fine lines of the electrostatic latent image, by maintaining a small amount of the coloring ink independently so that the resolution of the final image can be reproduced, good quality without omission or collapse is obtained. It can reproduce a perfect image. Further, since the amount of the ink held in the aggregate of particles is limited, even if the protrusions of the colored ink form columns, the colored ink may move to the latent image support in a large amount. Absent.

In order to reduce the size and pitch of the ink holding section, the pattern of the aggregate of particles may be reduced. In forming a pattern of an aggregate of particles, since the pattern of the aggregate of particles is a kind of image, a high-definition pattern is formed by various known image forming means, for example, an electrophotographic image forming means. It can be formed at low cost.

[0027]

Embodiments of the present invention will be described below. FIG. 1 is a schematic configuration diagram of an image forming apparatus provided with an embodiment of a wet developing device of the present invention. This image forming apparatus basically has a charging unit 2, a wet developing unit 3, a transfer unit 4, a cleaning unit 5, and a discharging unit 6 around a latent image support 1 on which an electrostatic latent image is formed. Is arranged. The wet developing unit 3 is an embodiment of the wet developing device of the present invention. Details will be described later.

The latent image support 1 is rotated by a driving device (not shown) in the direction of the arrow in the figure, and first, the charging means 2 uniformly charges the surface. Next, laser ROS
(Raster Output Scanner) 7 performs image exposure to form an electrostatic latent image. The latent image support 1 on which the latent image latent image is formed is developed by the wet developing means 3 to form a colored ink image on the surface of the latent image support 1. After that, the formed colored ink image is transferred to a predetermined transfer target medium 114 by the transfer unit 4. After the latent image support 1 is cleaned by the cleaning unit 5, the latent image support 1 is subjected to a charge removal process by the charge removal unit 6 to prepare for the next image formation.

FIG. 2 is a schematic structural view of an embodiment of the wet developing apparatus of the present invention used as the wet developing means 3 shown in FIG. The wet developing device shown in FIG. 2 includes an ink tank 31 containing a colored ink 12, an ink carrier 11,
An air nozzle 32 is provided. Coloring ink used 12
There is no particular limitation, it is possible to use aqueous ink,
Here, a dye or fine pigment dispersed in water is used.

FIG. 3 is an external view of the ink carrier 11 used in the wet developing apparatus shown in FIG. 2, FIG. 4 is an enlarged view of a part A shown in FIG. 3, and FIG. It is the top view (a) and sectional drawing (b) which show it further expanded. As shown in FIG. 3, the ink carrier 11 is formed in a drum shape or a roll shape. A tracking roll 111 that holds the surface of the carrier 11 at a constant interval is rotatably mounted. The ink carrier 11 is, as shown in FIG. 5B, a conductive support 112.
The dielectric layer 113 has a structure in which a plurality of solid particles 1 are formed on the surface of the dielectric layer 113.
An aggregate of solid particles consisting of 4 is arranged in a pattern,
Fixed. The colored ink 12 is held in the voids between the particles of the plurality of solid particles 14 constituting each aggregate.

If the solid particles 14 can be firmly fixed on the surface of the ink carrier 11 by any means and can penetrate and hold the colored ink between adjacent solid particles in each assembly, the material and shape are particularly limited. There is no limitation, for example, fine glass spheres, plastic spheres, particulate resin,
Metal spheres or the like can be used, and these particles have high ink affinity to the used coloring ink and can hold the coloring ink well. The particle size of the solid particles 14 is
Although those having a particle size of about 1 to 50 μm can be used, particles having a particle diameter of 20 μm or less are suitable for forming a fine pattern of solid particles, and if the amount of ink is too small, the developability deteriorates. Solid particles having a particle size of about 5 μm to 20 μm are preferred. As a method for fixing the solid particles 14, a method in which an adhesive or a sticky fine pattern is formed on the ink carrier 11 and the solid particles 14 are adhered and fixed thereto, and a thin layer is formed on the entire surface of the ink carrier 11. After forming the adhesive layer, a method of transferring the solid particles 14 formed in advance in a pattern and bonding and fixing the solid particles 14 in advance, and transferring the solid particles 14 formed in advance in a pattern to the ink carrier 11
By supplying a low-viscosity adhesive solution after the adhesive transfer onto the solid particles, or by solid particles 1
For example, a method of bonding and fixing by heating, melting, and cooling 4 can be used.

In particular, according to a method in which a pattern of arbitrary solid particles formed by using various image forming methods such as an electrophotographic method is transferred onto the dielectric layer 113 and fixed, the ink carrier 11 is extremely inexpensive. Can be created. Note that the dielectric layer 113 may be a film or sheet that satisfies desired characteristics with respect to ink repellency, strength, and the like, wound around the support 112.
Also, without providing the dielectric layer 113, the conductive support 112
An aggregate of the solid particles 14 may be arranged and fixed on the pattern itself.

With respect to the pattern of the aggregate of the solid particles 14, FIGS. 3 to 5 show examples of 40% halftone dot patterns, but various other patterns are also applicable. However, it should be noted at this time that the peripheral surface moving speed ratio between the ink carrier 11 and the latent image support 1 must be set depending on the pattern of the aggregate of the solid particles 14. For example, in the pattern examples of FIGS. 3 to 5, when the peripheral surfaces of the ink carrier 11 and the latent image support 1 are moved at a constant speed,
High-density development of 40% or more halftone dots cannot be performed. Accordingly, the ink transport carrier 1 is arranged such that all portions of the surface of the latent image support 1 always face the ink holding portion (aggregate of solid particles) of the ink transport carrier 11 at least once.
It is preferable to set a ratio of the peripheral surface moving speed of the latent image support 1 to that of the latent image support 1. However, when the dot gain after development is taken into consideration, the entire surface of the latent image support 1 does not always need to face the ink holding unit of the ink carrier 11 in some cases.

In the wet development process, first, the ink carrier 11 partially immersed in the colored ink 12 in the ink tank 31 shown in FIG. The ink 12 is supplied. As shown in FIGS. 4 and 5, the supplied colored ink is satisfactorily permeated and held in the gaps between adjacent solid particles in each aggregate of the solid particles 14. afterwards,
Air is blown onto the surface of the ink carrier 11 holding the colored ink by the air nozzle 32, and the ink carrier 1
(1) Unnecessary ink adhered and remaining on a portion other than the portion where the aggregate of solid particles 14 is fixed is removed.

When the ink carrier 11 whose surface is made of an ink repellent material or the ink carrier 11 whose surface is made of an ink repellent material is used as the ink carrier 11, the solid particles on the surface of the ink carrier 11 can be used. Unnecessary ink hardly adheres to portions other than the portion where the aggregate is fixed, and it is very easy to remove the unnecessary ink. Examples of the ink repellent treatment material or the ink repellent material include a film of a silicone release agent, a baking film or an adsorbing film of silicon oil or various modified silicone oils, a film of a silicon silane coupling material, a silicon varnish film, and a silicon rubber. Examples include a film or silicon rubber, and a composite of silicon rubber and various metals, rubber, plastic, ceramic, and the like. In addition, various coatings of a fluorine-based material, a fluorine-based resin or rubber, and the like can be given.

In the present embodiment, particles having a size of 5 μm to 6 μm are used as the solid particles 14 forming a pattern, and an aggregate having a size of 20 μm to 100 μm is used as an aggregate of the solid particles 14. Set of 2
Even in the case of an extremely fine pattern arranged at a pitch of 0 μm, the colored ink is satisfactorily permeated and retained only in the aggregate of solid particles.

As shown in FIG. 2, the ink carrying carrier 11 is disposed at a position facing the latent image support 1 with a small distance, and for example, is rotated around the latent image support 1 by a rotation driving device (not shown). In the same direction as the surface moving direction, the latent image support 1 is rotationally driven at a speed twice as high as the peripheral surface moving speed. The minute distance from the latent image support 1 is determined by a tracking roll 111 rotatably attached to the end of the ink carrier 11.
(See FIG. 3) is brought into contact with the end of the latent image support 1 to maintain the same constant.

A bias voltage is applied to the ink carrier 11 by voltage applying means (not shown), and a developing electric field formed between the electrostatic carrier and the electrostatic latent image formed on the latent image support 1 by the bias voltage. The intensity is controlled. The bias voltage is applied because when the pattern on the ink carrier 11 is miniaturized, the amount of ink held in each aggregate of the solid particles 14 is reduced, and the developability is reduced as shown in FIG. Therefore, the developing property is improved by applying the developing bias voltage.

FIG. 6 is a schematic diagram showing the behavior of the colored ink during development in the present embodiment. In this embodiment,
By independently holding the coloring ink 12 in small amounts according to the required resolution on the ink carrier 11, protrusions of the ink due to the developing electric field are generated in each of the aggregates of the independent solid particles 14, Even if the colored ink held in the adjacent aggregate forms a projection and the projection grows at that portion, the ink is not biased because the colored inks are independent of each other. Protrusions of the colored ink can be satisfactorily generated from each body, and a uniform solid image without omission can be formed. Also, for fine image portions such as fine lines, a good image without omissions or crushing can be reproduced by independently holding a small amount of colored ink in advance so that the resolution of the final image can be reproduced in advance. .

In the present embodiment, the amount of ink held in each aggregate of the solid particles 14 is regulated by the size and the number of the solid particles 14 constituting the aggregate.
Even if the projections of the colored ink form pillars, it is possible to prevent the colored ink from moving toward the latent image support in a large amount. FIG. 7 is a schematic configuration diagram of another embodiment of the wet developing device. The differences from the embodiment with reference to FIG. 2 will be described.

The wet developing device shown in FIG. 7 is provided with a roll member 33 facing the ink carrier 11 in a non-contact manner with a small distance as unnecessary ink removing means. The roll member 33 is rotationally driven by a rotation driving unit (not shown) so that the peripheral surface moves in a direction opposite to the peripheral surface moving direction of the ink carrier 11. The minute distance from the ink carrier 11 is kept constant by bringing the tracking roller 331 rotatably attached to the end of the roll member 33 into contact with the ink carrier 11.

Ink carrier 1 immersed in ink tank 31
Since the colored ink 12 accompanies one surface, a meniscus of the colored ink 12 is formed at a minute interval between the ink carrier 11 and the roll member 33. When a meniscus is formed, a shear force is generated in the meniscus due to a speed difference between the ink carrier 11 and the roll member 33, and the amount of ink incident on the ink carrier 11 is controlled by controlling the speed difference. Therefore, the unnecessary colored ink 12 can be satisfactorily removed by using the roll member 33. The unnecessary ink attached to the roll member 33 is scraped off by the blade 34 and collected in the ink tank 31.

With respect to the method of supplying the colored ink 12, in each of the above-described embodiments, the ink carrier 11 is partially immersed in the colored ink tank 31 to transfer the colored ink 12 to the ink carrier 11.
However, various ink supply means such as a roll member and a nozzle can be applied as long as the ink can be supplied uniformly to the ink carrier.

[0044]

As described above, according to the present invention,
Using an ink carrier in which the aggregate of particles is fixed in a pattern, and applying the liquid wetting and the capillary phenomenon to hold the colored ink in the gap between adjacent solid particles, the following effects are obtained. .

Since the aggregate of particles is used as the holding portion for the colored ink, an ink carrier having a fine pattern of the ink holding portion can be easily and inexpensively formed. Also,
When the colored ink is supplied to the ink carrier, the colored ink naturally penetrates and is held in the gaps between the particles, so that the ink can be supplied more easily without any supply loss compared to the related art.

Further, the colored ink once permeated and held in the void does not flow out even if a certain external force is applied, so that unnecessary ink attached to portions other than the ink holding portion can be easily removed. In removing the unnecessary ink, even a non-contact unnecessary ink removing device such as a non-contact air blowing method or a reverse roll method can remove the unnecessary ink satisfactorily. The carrier is not subjected to frictional sliding at all, and the durability is greatly improved. If the surface of the colored ink carrier has ink repellency to the used colored ink, the removal of the unnecessary ink becomes very easy, and a large-scale unnecessary ink removing means becomes unnecessary.

If a fine particle is used and a fine pattern is formed, a fine pattern of a small amount of colored ink can be easily formed, and a fine latent image portion can be reproduced well. Since each aggregate of particles is formed as an independent pattern, even in a uniform solid image area, ink projections are generated independently from each aggregate, and adjacent colored inks form projections. However, the colored ink is not attracted to the adjacent protrusions, and a uniform solid image can be formed.

Further, even if the projections of the colored ink adhere to the latent image support to form columns of ink, it is possible to prevent a large amount of ink from moving to the latent image support. As a result, an inexpensive wet recording apparatus that can form a uniform solid image without omission and a high-resolution image without crushing using an aqueous colored ink is formed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus provided with an embodiment of a wet developing device of the present invention.

2 is used as the wet developing means 3 shown in FIG.
FIG. 1 is a schematic configuration diagram of an embodiment of a wet developing device of the present invention.

FIG. 3 is an outline view of an ink carrier used in the wet developing device shown in FIG. 2;

FIG. 4 is an enlarged view of a portion A shown in FIG.

FIGS. 5A and 5B are a plan view (a) and a sectional view (b) showing a portion B shown in FIG. 4 in a further enlarged manner.

FIG. 6 is a schematic diagram illustrating the behavior of a colored ink during development in the embodiment of the present invention.

7 is used as the wet developing means 3 shown in FIG.
FIG. 3 is a schematic configuration diagram of an embodiment different from the embodiment shown in FIG. 2 of the wet developing device of the present invention.

FIG. 8 is a schematic diagram showing an outline of a developing process by a conventionally proposed wet developing method.

FIG. 9 is a diagram illustrating the intensity of an electric field required for development with respect to the diameter of an ink droplet on an ink carrier.

FIG. 10 is a diagram showing the ink droplet diameter on a latent image support after development with respect to the ink droplet diameter on an ink carrier.

FIG. 11 is a schematic view showing an outline of a conventionally proposed wet developing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Latent image support 2 Charging means 3 Wet developing means 4 Transfer means 5 Cleaning means 6 Static elimination means 7 Laser ROS 10 Electrostatic latent image 11 Ink carrier 12 Colored ink 14 Solid particles 31 Ink tank 32 Air nozzle 33 Roll member 34 Blade 111 Tracking roll 114 Transfer media

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03G 15/10

Claims (3)

(57) [Claims] 1. An ink carrying carrier for holding a colored ink on a surface thereof and transporting the colored ink to a position close to a latent image support on which a latent image is formed on the surface, and transported by the ink carrying carrier. A wet developing device for developing the latent image by adhering the colored ink to the latent image support surface in a pattern corresponding to the pattern of the latent image formed on the latent image support surface; The carrier is fixed to the surface of the ink carrier, each of which is an aggregate of a plurality of particles, and the colored ink is held in a state where the colored ink is separated for each aggregate in the interparticle gap portion of the aggregate. A wet developing device comprising a large number of assemblies. 2. A disposed at a position spaced from the ink-carrying carrier claims characterized by comprising the unnecessary ink removing device for removing colored ink adhering to a portion other than the interparticle void portion of the aggregate Item 6. A wet developing device according to Item 1 . 3. The wet developing device according to claim 1, wherein the surface of the ink carrier is ink-repellent.