JP2002091171A - Image forming device and image transfer method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device constituted so that a recording medium is prevented from being wetted by the solvent of liquid developer. SOLUTION: This image forming device is equipped with a dryer for volatilizing the solvent in the liquid developer on an intermediate image carrier and drying toner particles being a coloring resin component without melting them, and a re-electrifying device for re-electrifying toner particles which are dried on the intermediate image carrier and nearly lose charge. According to this image transfer method, the toner particles dried on the intermediate image carrier are re-electrified and transferred to the recording medium by electrostatic force, so that electrostatic transfer is easily performed even when plain paper is selected as the recording medium.

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 using a liquid developer.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus using a liquid developer, for example, in the case of a laser printer, performs development after forming a latent image on a photosensitive member. In this development, the liquid developer on the photoreceptor, which is an image forming member, is electrostatically transferred to the intermediate image carrier by the principle of electrophoresis, and the toner is melted on the intermediate image carrier. In some media, transfer is performed again by applying heat and pressure to the medium.

[0003] Alternatively, there is a method in which electrostatic transfer is performed again from an intermediate image carrier to a recording medium by the principle of electrophoresis.

[0004] Such conventional techniques include, for example,
There is JP-A-8-328391.

[0005]

In this conventional technique, when heat and pressure are applied to the recording medium from the intermediate image carrier to transfer the heat, heat is generated in the process, and this heat stays in the apparatus. It is necessary to perform processing for temperature rise and exhaust heat.

For example, when transferring toner from an intermediate image carrier to a recording medium, it is necessary to heat the intermediate image carrier, and the heat is transferred between the photosensitive member as an image forming member and the intermediate image carrier. May be transmitted to the photoreceptor through a portion where the photoreceptor is in contact with the photoreceptor, and may deteriorate the photoreceptor.

In the case where electrostatic transfer is performed from an intermediate image carrier to a recording medium, the toner on the intermediate transfer body is transferred by a principle of electrophoresis in a solvent of a liquid developer. If an arbitrary sheet is selected as the medium, if the liquid developer contains a large amount of solvent, the sheet becomes wet with the solvent, which causes curling of the sheet in the fixing unit.

On the other hand, when the amount of the solvent in the liquid developer is small, the solvent is quickly absorbed by the paper, and the mechanism of electrostatic transfer by electrophoresis may not work well.

As described above, when the liquid developer is electrostatically transferred from the intermediate image carrier to the recording medium, a problem specific to the liquid developer, such as the recording medium getting wet with or absorbing the solvent. However, it is necessary to use a recording medium that does not cause such a problem.

On the other hand, Japanese Patent Application Laid-Open No. 8-328391 discloses
As described above, Japanese Patent Application Laid-Open Publication No. H11-133873 does not disclose means for solving the problems specific to the liquid developer for the recording medium.
A transfer structure for preventing image deletion on a recording medium when a highly viscous liquid developer is used is disclosed.

An object of the present invention is to provide an image forming apparatus which prevents a recording medium from being wetted by a solvent of a liquid developer.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus of an electrophotographic type using a liquid developer, and an image forming member and a latent image forming means for forming a latent image on the image forming member. A developing device for visualizing the latent image formed on the image forming member, an intermediate image carrier disposed so as to contact the image forming member, and an intermediate image carrier A drying unit for volatilizing a solvent of the liquid developer for forming an image transferred on a holding body and drying a colored resin component in the liquid developer, and injecting a charge into the dried colored resin component; And a recharging device for recharging.

Further, in an electrophotographic image forming apparatus using a liquid developer, an image forming member, a latent image forming means for forming a latent image on the image forming member, and A developing device that develops an image corresponding to the formed latent image, an intermediate image carrier disposed so as to be in contact with the image forming member, and an image transferred on the intermediate image carrier Drying means for volatilizing a solvent of the liquid developer and drying a colored resin component in the liquid developer, and a recharger for injecting electric charge into the dried colored resin component and recharging the same. This is achieved by providing a charging device.

Further, in an electrophotographic image forming apparatus using a liquid developer, an image forming member, a latent image forming means for forming a latent image on the image forming member, and A developing device that develops an image corresponding to the formed latent image, an intermediate image carrier disposed so as to be in contact with the image forming member, and an image transferred on the intermediate image carrier Drying means for volatilizing a solvent of the liquid developer and drying a colored resin component in the liquid developer, and a recharger for injecting electric charge into the dried colored resin component and recharging the same. This is achieved by providing a charging device.

Further, in the electrophotographic image transfer method using a liquid developer, an image visualized corresponding to a latent image formed on the image forming member by the liquid developer is transferred to the image forming member. At the time of the first transfer for transferring the liquid developer from the image forming member and the intermediate image carrier using the potential difference between the image forming member and the intermediate image carrier, the liquid developer constituting the image is transferred to the intermediate image carrier. The liquid developer electrostatically transferred onto the carrier, the solvent of the liquid developer electrostatically transferred was volatilized by a drying unit, and the colored resin component in the liquid developer was dried without melting, and then dried by a recharging device. This is achieved by injecting a charge into the colored resin component and recharging it, and performing a second transfer by electrostatic transfer from the intermediate image carrier to a recording medium.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic structural view showing an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a photosensitive belt as an image forming member. Reference numeral 2 denotes a driving roller, reference numeral 3 denotes a driven roller, and reference numeral 4 denotes a tension roller. The photosensitive belt 1 is stretched around at least three of these rollers 2, 3, and 4. There is no problem even if the number of these rollers 2, 3, 4 is four or more as required.

In this embodiment, the photosensitive belt 1 is stretched to five rollers, and the intermediate transfer drum 20 as an intermediate image carrier is brought into contact with the photosensitive belt 1 under tension.

Around the photosensitive belt 1 there are provided a charging device 5 for charging the photosensitive belt 1 and a latent image forming device 6 for forming a latent image on the photosensitive belt 1.

Reference numeral 10 denotes a color developing device for visualizing the latent image on the photosensitive belt 1 in accordance with the latent image. Reference numeral 20 denotes an intermediate transfer drum which is attached to the photoreceptor belt 1 so as to be in contact therewith and serves as an intermediate image carrier. Reference numeral 7 denotes a cleaning device for removing the liquid developer remaining on the photosensitive belt 1. 8
Is a static eliminator for neutralizing the photoreceptor belt 1.

Around the intermediate transfer drum 20, a charging device 21 for charging the surface of the intermediate transfer drum 20, a drying device 22 for drying the liquid developer on the intermediate transfer drum 20, A recharging device 23 is provided for charging and recharging the toner particles in a dry state.

Reference numeral 24 denotes a transfer roller for electrostatically transferring the dried toner particles from the intermediate transfer drum 20 to a recording medium such as paper. 25 is an intermediate transfer drum 2
This is a cleaning device that removes the toner remaining on the surface of the toner. Reference numeral 26 denotes a neutralization device for neutralizing the surface of the intermediate transfer drum 20.

In the present embodiment, the charging device 21 and the recharging device 23 are arranged as separate devices, but one device may have the roles of both. Further, a corotron charger or a scorotron charger may be used as a charging unit of the intermediate transfer drum 20, and a predetermined potential is applied to the intermediate transfer drum 20 so that a liquid is supplied between the photosensitive belt 1 and the intermediate transfer drum 20. Power supply 2 for forming an electric field for electrostatically transferring the developer according to the electrophoresis principle
7 may be arranged. Further, a transfer charger may be arranged instead of the transfer roller 24.

Although not shown, a fixing device for fixing the toner transferred to the recording medium such as paper is provided at the destination of the recording medium.

The intermediate transfer drum 20 is composed of a metal core and an elastic dielectric material which does not swell in the solvent of the liquid developer. The reason why the dielectric has elasticity is to secure good adhesion to the paper at the time of transfer, particularly at the time of transfer to paper as a recording medium, and to realize good transfer.

The drying device 22 is composed of a heater and a fan. The intermediate device transfers warm air to the extent that the solvent of the liquid developer on the intermediate transfer drum 20 is volatilized and the colored resin is dried without melting. The drum 20 is blown. This warm air is adjusted so as not to disturb the image on the intermediate transfer drum 20. The drying device 22 can obtain the same effect by heating the entire intermediate transfer drum 20 to a predetermined temperature.

The recharging device 23 uses a corotron charger. The function thereof is as follows. In order to realize transfer by electrostatic transfer to a recording medium at a transfer roller 24 described later, the transfer roller 24 dries and almost loses electric charge, and adheres onto the intermediate transfer drum 20 mainly by physical adhesion. That is, the electric charge is imparted to the toner particles without disturbing the image. Therefore, as long as this function is achieved, the present invention is not limited to the corotron charger, but may be a scorotron charger or another recharging device.

The transfer roller 24 is formed by forming a conductive elastic body having good releasability around a cored bar. Further, the transfer roller 24 is connected to a power supply 28 so that a transfer bias voltage suitable for transferring the toner particles on the intermediate transfer drum 20 to a sheet as a recording medium can be applied. In the figure, an arrow B indicates a paper transport route.

Incidentally, three or more rollers for stretching the photosensitive belt 1, a charging device 5 for charging the photosensitive belt 1, a latent image forming device 6, and a liquid developer remaining on the photosensitive belt 1 are removed. A cleaning device 7, a static elimination device 8 for neutralizing the photoreceptor belt 1, a charging device 21 for charging the surface of the intermediate transfer drum 20, a cleaning device 25 for removing toner remaining on the intermediate transfer drum 20, and an intermediate transfer drum 2
As the static eliminator 26, the power source 28, and the fixing device that eliminate static electricity from the surface 0, conventional techniques known in the art can be used as they are.

The liquid developer of this embodiment has a structure in which a coloring resin, a charge control agent, and a dispersant are dispersed in a solvent having a high electric resistance, and has a nonvolatile content of 5 to 40% by weight. Used.

FIG. 2 is a view showing the structure of a developing device provided with the present invention.

In FIG. 2, a predetermined amount of a liquid developer 11 is stored in a developing tank 12. The pumping roller 13 is arranged so that a part thereof is immersed in the liquid developer 11 in the developing tank 12. With the rotation of the pumping roller 13, the liquid developer 11 is pumped to the surface of the pumping roller 13. The pumped liquid developer 11 is supplied to the developing roller 14, and the regulating blade 15 regulates the liquid film thickness on the developing roller 14 to a predetermined value. Further, since a predetermined potential can be applied to the developing roller 14 by a power source (not shown), a developing bias voltage for performing good development can be applied between the developing roller 14 and the photosensitive belt 1.

In the present embodiment, the pumping roller 13 and the developing roller 14 rotate in the same direction. However, since it is sufficient that the liquid developer 11 can be supplied stably at a predetermined liquid film thickness, it is not always necessary to rotate in the same direction. Absent.

The configuration of the developing device shown in FIG. 2 is merely an example, and other configurations may be used as long as the developing device stably develops the high-concentration liquid developer of the present embodiment.

The image transfer procedure of the embodiment shown in FIG. 1 will be described. The surface of the photosensitive belt 1 is charged substantially uniformly by the charger 5. Next, a latent image is formed on the surface of the photoreceptor belt 1 by the latent image forming device 6. Subsequently, each color developing unit 10-a, 1
Of the 0-b, 10-c, and 10-d, development is performed by the first color developing unit (for example, 10-a), and the latent image is visualized. At this time, a developing bias voltage is applied between the developing device 10 and the photoreceptor belt 1 to prevent image deterioration due to toner adhesion caused by physical adhesion of the liquid developer to the photoreceptor belt 1.

FIG. 3 is a schematic diagram illustrating electrostatic transfer from the photosensitive belt to the intermediate transfer drum.

In FIG. 3, the surface of the intermediate transfer drum 20 is also charged by the charger 21 to the opposite polarity to the toner in order to perform electrostatic transfer. The contact portion between the photosensitive belt 1 and the intermediate transfer drum 20 is in contact with each other via the liquid developer 11 attached to the photosensitive belt 1. At this time, the toner particles 30 on the photoreceptor belt 1 are attracted toward the intermediate transfer drum 20 by electrophoresis according to the electric field formed by the electric charge on the surface of the intermediate transfer drum 20, and electrostatic transfer is performed.

The arrow A in the figure indicates the direction of the electrostatic force acting on the toner particles 30. In this embodiment, the intermediate transfer drum 20 is charged and the electric field is formed by the charge.
Instead, a predetermined potential difference may be applied between the intermediate transfer drum 20 and the photoreceptor belt 1 and electrostatic transfer may be realized by an electric field formed by the potential difference, or an electric field may be formed by both to achieve electrostatic transfer. Electrotransfer may be realized.

The liquid developer 11 remaining on the photoreceptor belt 1 is removed by the cleaning device 7 shown in FIG. 1, and thereafter, the surface of the photoreceptor belt 1 is discharged by the discharging device 8. The liquid developer 11 electrostatically transferred onto the intermediate transfer drum 20 is subsequently supplied to the drying device 22.
As a result, the solvent of the liquid developer 11 is volatilized, and the toner particles 30 as the colored resin component are dried without melting. Since the toner particles 30 of the liquid developer 11 form an electric double layer and are dispersed in the solvent, the charge is lost by drying, and it is considered that the toner particles 30 adhere to the surface of the intermediate transfer drum 20 only by physical adhesion. . When the toner particles 30 are melted, not only the electrostatic transfer to the recording medium becomes difficult, but also the required amount of heat is increased, and the temperature of the apparatus is increased. Dry to the extent that it does not.

The state before and after drying will be described with reference to the schematic diagram shown in FIG. 4A shows a state before drying, and FIG. 4B schematically shows a state of the toner particles 30 on the intermediate transfer drum 20 after drying.

Subsequently, in order to eliminate potential variations on the surface of the intermediate transfer drum 20, the surface of the intermediate transfer drum 20 is neutralized by the neutralizer 26. Next, the same operation is performed for the second and subsequent colors. At the time of the electrostatic transfer from the photoreceptor belt 1 to the intermediate transfer drum 20, there is no significant difference except that the toner particles up to the previous color adhere to the surface of the intermediate transfer drum 20. At this time, the charging amount for charging the intermediate transfer drum 20 by the charger 21 may be adjusted for each color.

After the color liquid developer is electrostatically transferred onto the intermediate transfer drum 20 and the solvent of the liquid developer is volatilized by the drying device 22, the intermediate transfer drum 2 is recharged by the recharging device 23.
Electric charges are injected into the toner particles 31 superimposed on 0, and the toner particles 31 are recharged.

In this embodiment, a corotron charger is used as the recharging device 23. However, the recharging device 23 is not limited to this as long as it performs recharging without disturbing the superimposed image.

FIG. 5 is a schematic diagram showing a state before and after recharging.
FIG. 5A schematically shows a state before recharging, and FIG. 5B schematically shows a state of the toner particles 31 superimposed on the intermediate transfer belt 20 after recharging.

5A and 5B, the intermediate transfer drum 20
A sheet 40 as a recording medium is conveyed between the sheet and the transfer roller 24, and the transfer to the sheet 40 by electrostatic transfer is performed. At this time, a predetermined transfer bias potential required for good electrostatic transfer is applied to the transfer roller 24 by the power supply 28. In addition, due to the elasticity of the intermediate transfer drum 20, the adhesion between the surface of the intermediate transfer drum 20 and the sheet 40 is ensured. The paper 40 and the intermediate transfer drum 20 are pressed,
The toner particles 31 charged on the intermediate transfer drum 20 are electrostatically transferred to the paper 40 by an electric field generated by a potential difference between the intermediate transfer drum 20 and the transfer roller 24.

FIG. 6 schematically shows how the toner particles 31 on the intermediate transfer drum 20 are electrostatically transferred onto the paper 40 by receiving an electrostatic force indicated by an arrow C. After the toner particles 31 have been transferred onto the paper 40 in the procedure described above, FIG.
The toner particles 3 on the paper 40 by a fixing device not shown in FIG.
1 is fused and fixed to obtain a color image output.

Next, a second embodiment of the present invention will be described with reference to FIG. The same components as those in the first embodiment described with reference to FIG. 1 are denoted by the same reference numerals.

In FIG. 7, a charging device 5 for charging the photosensitive drum 51 and a latent image forming device 6 for forming a latent image on the photosensitive drum 51 are provided around a photosensitive drum 51 serving as an image forming member. A color developing unit 10 for visualizing the latent image on the body drum 51; an intermediate transfer belt 60 as an intermediate image carrier mounted in contact with the photosensitive drum 51; A cleaning device 7 for removing the liquid developer remaining on the surface 51 and a charge removing device 8 for removing charge from the photosensitive drum 51 are arranged.

The intermediate transfer belt 60 includes a driving roller 61,
It is stretched by a driven roller 62, a tension roller 63, second transfer rollers 64a and 64b, and other rollers. The intermediate transfer belt 60 uses the tension to
It is configured to abut. Around the intermediate transfer belt 60, a charging device 21 for charging the surface of the intermediate transfer belt 60, a drying device 22 for drying the liquid developer on the intermediate transfer belt 60, and a state of being dried on the intermediate transfer belt 60. A recharging device 23 for charging and recharging the toner particles, a transfer roller 24 for electrostatically transferring the dried toner particles from the intermediate transfer belt 60 to a recording medium such as paper, A cleaning device 25 for removing the toner remaining on the intermediate transfer belt 60 and a static eliminator 26 for neutralizing the surface of the intermediate transfer belt 60 are provided.

In the present embodiment, the charging device 21 and the recharging device 23 are arranged as separate devices, but one device may have the roles of both. As a charging unit of the intermediate transfer belt 60, a corotron charger or a scorotron charger may be used, or a predetermined potential may be applied to the intermediate transfer belt 60 so that the photosensitive drum 51 and the intermediate transfer belt 60 are charged. A power supply 27 for generating an electric field for electrostatically transferring the liquid developer according to the principle of electrophoresis may be provided. Further, a transfer charger may be arranged instead of the transfer roller 24. Although not shown, a fixing device for fixing the toner transferred to a recording medium such as a sheet is disposed at a destination of the recording medium.

The photosensitive drum 51, a charging device 5 for charging the photosensitive drum 51, a latent image forming device 6, a photosensitive drum 5
1, a cleaning device 7 for removing the liquid developer remaining on the photosensitive drum 51, a static eliminator 8 for removing static from the photosensitive drum 51, a plurality of rollers for stretching the intermediate transfer belt 60, and an intermediate transfer belt 6.
A charging device 21 for charging the surface, and a cleaning device 2 for removing toner remaining on the intermediate transfer belt 60
5. The static eliminator 26 and the fixing device for neutralizing the surface of the intermediate transfer belt 60 can be formed by using a conventionally known technique.

As in the first embodiment, the liquid developer of this embodiment has a structure in which a coloring resin, a charge control agent, and a dispersant are dispersed in a solvent having a high electric resistance.
% High concentration is used.

The developing device 10 of this embodiment also has a configuration as shown in FIG. 2 as described in the first embodiment, and a duplicate description will be omitted, but the developing device 10 shown in FIG. The configuration is merely an example, and other configurations may be used as long as the developing device stably develops the high-concentration liquid developer of the present embodiment.

The intermediate transfer belt 60 according to the present embodiment has a structure in which a conductive base material having excellent abrasion resistance and an elastic dielectric material which does not swell in the solvent of the liquid developer are formed on the base material. Has become. The reason for having elasticity is to secure good adhesion to the paper at the time of transfer, particularly at the time of transfer to paper as a recording medium, and to realize good transfer.

The drying device 22 and the recharging device 23 of this embodiment
The transfer roller 24 is the same as that described in the first embodiment, and a description thereof will be omitted.

Needless to say, instead of the transfer roller 24, electrostatic transfer may be realized using a transfer charger (not shown).

Next, an image transfer procedure of the image forming apparatus according to the second embodiment described with reference to FIG. 7 will be described.

First, the surface of the photosensitive drum 51 is charged substantially uniformly by the charger 5. Next, a latent image is formed on the surface of the photosensitive drum 51 by the latent image forming device 6. Subsequently, of the respective color developing units 10-a, 10-b, 10-c and 10-d, development is performed by the developing unit of the first color (for example, 10-a), and the latent image is visualized. Is done. At this time, a developing bias voltage is applied between the developing device 10 and the photosensitive drum 51 to prevent image deterioration due to toner adhesion to the photosensitive drum 51 due to physical adhesion of the liquid developer. .

On the other hand, the surface of the intermediate transfer belt 60 is also charged by the charger 21 to a polarity opposite to that of the toner in order to perform electrostatic transfer. Photoconductor drum 51 and intermediate transfer belt 60
Are in contact with each other via the liquid developer 11 attached to the photosensitive drum 51 at the contact portion between the two. At this time, the toner particles on the photosensitive drum 51 are attracted toward the intermediate transfer belt 60 by electrophoresis according to the electric field formed by the charge on the surface of the intermediate transfer belt 60, and the electrostatic transfer is performed. In this embodiment, the intermediate transfer belt 60 is charged and an electric field is formed by the charge. Instead, a predetermined potential difference is applied between the intermediate transfer belt 60 and the photosensitive drum 51, and the potential difference is formed. The electrostatic transfer may be realized by an electric field. Alternatively, an electrostatic field may be realized by forming an electric field by both of them.

The liquid developer 11 remaining on the photosensitive drum 51 is removed by the cleaning device 7, and thereafter,
The surface of the photosensitive drum 51 is neutralized by the neutralization device 8.

The liquid developer 11 electrostatically transferred onto the intermediate transfer belt 60 is subsequently evaporated by the drying device 22 so that the solvent of the liquid developer 11 is volatilized, and the toner particles 30 as the colored resin component are not melted. Dried. Liquid developer 11
Since the toner particles 30 are dispersed by forming an electric double layer in the solvent, it is considered that the toner particles 30 lose their charge by drying and adhere to the surface of the intermediate transfer belt 60 only by physical adhesion. When the toner particles 30 are melted, not only the electrostatic transfer to the recording medium becomes difficult, but also the required amount of heat increases, which causes an undesirable increase in the temperature of the apparatus. Dry to the extent that it does not melt.

Subsequently, in order to eliminate potential variations on the surface of the intermediate transfer belt 60, the surface of the intermediate transfer belt 60 is neutralized by the neutralizer 26.

Next, the same operation is performed for the second and subsequent colors. From the photosensitive drum 51 to the intermediate transfer belt 6
There is no significant difference except that the toner particles up to the previous color adhere to the surface of the intermediate transfer belt 60 at the time of the electrostatic transfer to 0. At this time, the intermediate transfer belt 60 is
May be adjusted for each color.

After the liquid developer of the color is electrostatically transferred onto the intermediate transfer belt 60 and the solvent of the liquid developer is volatilized by the drying device 22, the intermediate transfer belt 6 is recharged by the recharging device 23.
Electric charges are injected into the toner particles 31 superimposed on 0, and the toner particles 31 are recharged. In this embodiment, a corotron charger is used as the recharging device 23.
It is not necessary to limit to this as long as recharging is performed without disturbing the superimposed image.

The paper 40 as a recording medium is conveyed between the intermediate transfer belt 60 and the transfer roller 24, and the transfer to the paper 40 is performed by electrostatic transfer. At this time, the transfer roller 2
Reference numeral 4 denotes a power supply 28 to which a predetermined transfer bias potential required for good electrostatic transfer is applied. Further, the adhesion between the surface of the intermediate transfer belt 60 and the paper 40 is ensured by the tension and elasticity of the intermediate transfer belt 60. A thin arrow B in FIG. 7 indicates a paper transport route.

The paper 40 and the intermediate transfer belt 60 are pressed, and the toner particles 31 charged on the intermediate transfer belt 60 are charged.
Is electrostatically transferred to the paper 40 by an electric field generated by a potential difference between the intermediate transfer belt 60 and the transfer roller 24.

After the toner particles 31 are transferred onto the paper 40 in the above-described procedure, the toner particles 31 on the paper 40 are melted and fixed by a fixing device not shown in FIG. 7, and a color image output is obtained.

[0069]

According to the present invention, it is possible to provide an image forming apparatus in which the wetting of a recording medium by a solvent of a liquid developer is prevented.

[Brief description of the drawings]

FIG. 1 is a schematic view of an image forming apparatus provided with an image transfer method of the present invention.

FIG. 2 is a schematic view showing an example of a developing device applied to an image forming apparatus provided with the image transfer method of the present invention.

FIG. 3 is a schematic diagram illustrating electrostatic transfer from a photoreceptor belt to an intermediate transfer drum of an image forming apparatus provided with the image transfer method of the present invention.

FIG. 4 is a schematic diagram illustrating a state in which a liquid developer is volatilized and a toner particle is dried by a drying device on an intermediate transfer drum of an image forming apparatus provided with the image transfer method of the present invention.

FIG. 5 is a schematic diagram illustrating recharging for realizing electrostatic transfer to a recording medium of the image forming apparatus provided with the image transfer method of the present invention.

FIG. 6 is a schematic diagram illustrating electrostatic transfer from an intermediate transfer drum to a recording medium in an image forming apparatus provided with the image transfer method of the present invention.

FIG. 7 is a schematic diagram illustrating an image forming apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Photoreceptor belt, 2 ... Drive roller, 3 ... Follower roller,
DESCRIPTION OF SYMBOLS 4 ... Tension roller, 6 ... Charging device, 7 ... Latent image forming device, 8 ... Cleaning device, 9 ... Static eliminator, 10 ... Developing device, 11 ... Liquid developer, 12 ... Developing tank, 13 ... Pumping roller, 14 ... Developing roller, 15: regulating blade,
16: Intermediate transfer drum, 17: Charging device, 18: Drying device, 19: Recharging device, 20: Transfer roller, 21: Cleaning device, 22: Static eliminator, 23: Power supply, 24: Power supply, 25: Toner particles, 26: toner particles, 27: paper, 28: photosensitive drum, 29: intermediate transfer belt, 30
.., A driving roller, 31 a driven roller, 32 a tension roller, 33 a second transfer roller.

Continued on the front page (72) Inventor Yukio Yamamoto 502 Kandamachi, Tsuchiura-shi, Ibaraki Pref. Machinery Research Laboratory, Hitachi, Ltd. (72) Inventor Junichi Matsuno 502 Kandate-cho, Tsuchiura-shi, Ibaraki Pref. In the machinery laboratory of Hitachi, Ltd. (72) Keiji Kamio 1-1-1 Higashitaga-cho, Hitachi, Ibaraki Japan Department F-term (Reference) 2H032 AA01 AA15 BA04 BA08 BA09 BA23 BA27 2H069 CA28 DA08 2H074 AA03 BB02 BB31 BB50 BB61 EE07

Claims (4)

[Claims] 1. An image forming apparatus of an electrophotographic type using a liquid developer, an image forming member, a latent image forming means for forming a latent image on the image forming member, and an image forming member on the image forming member. A developing device that develops an image corresponding to the formed latent image, an intermediate image carrier disposed so as to be in contact with the image forming member, and an image transferred on the intermediate image carrier Drying means for volatilizing a solvent of the liquid developer and drying a colored resin component in the liquid developer, and a recharger for injecting electric charge into the dried colored resin component and recharging the same. An image forming apparatus comprising: a charging device. 2. An electrophotographic image forming apparatus using a liquid developer, comprising: an image forming member; a latent image forming means for forming a latent image on the image forming member; A developing device that develops an image corresponding to the formed latent image, an intermediate image carrier disposed so as to be in contact with the image forming member, and an image transferred on the intermediate image carrier Drying means for volatilizing a solvent of the liquid developer and drying a colored resin component in the liquid developer, and a recharger for injecting electric charge into the dried colored resin component and recharging the same. An image forming apparatus comprising: a charging device. 3. An image forming apparatus of an electrophotographic type using a liquid developer, an image forming member, a latent image forming means for forming a latent image on the image forming member, and an image forming member on the image forming member. A developing device that develops an image corresponding to the formed latent image, an intermediate image carrier disposed so as to be in contact with the image forming member, and an image transferred on the intermediate image carrier Drying means for volatilizing a solvent of the liquid developer and drying a colored resin component in the liquid developer, and a recharger for injecting electric charge into the dried colored resin component and recharging the same. An image forming apparatus comprising: a charging device. 4. An electrophotographic image transfer method using a liquid developer, wherein an image visualized corresponding to a latent image formed on the image forming member by the liquid developer is transferred to the image forming member. At the time of the first transfer for transferring the liquid developer from the image forming member and the intermediate image carrier using the potential difference between the image forming member and the intermediate image carrier, the liquid developer constituting the image is transferred to the intermediate image carrier. The liquid developer electrostatically transferred onto the carrier, the solvent of the liquid developer electrostatically transferred was volatilized by a drying unit, and the colored resin component in the liquid developer was dried without melting, and then dried by a recharging device. An image transfer method, comprising: injecting a charge into the colored resin component to recharge it; and performing a second transfer by electrostatic transfer from the intermediate image carrier to a recording medium.