JP2001305887A - Liquid development electrophotographic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a material, a mechanism and a condition so as to remove liquid carrier with effect and stability. SOLUTION: A liquid development electrophotographic apparatus includes a developing assembly forming a toner image by allowing toner particles in liquid developer to attach to an image holding body according to electric field formed between the image holding body and the liquid developer, an intermediate transfer assembly being arranged so as to transfer the toner image held on the image holding body, and a transferring/fixing assembly melting/ transferring the transferred toner image onto a printing medium. The intermediate transfer assembly includes an excess carrier removing mechanism having a carrier removing roller so as to remove excess oil from a toner layer forming the image on the intermediate transfer assembly. The carrier removing roller comes in contact with the toner layer being heated to a temperature above or around the melting point, and a bias voltage is applied to the intermediate transfer assembly in the direction in which the toner particles are pressurized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid developing electrophotographic apparatus using a liquid toner, and more particularly, to a liquid developing electrophotographic apparatus having an excess carrier removing mechanism for removing excess oil from a toner layer for forming an image on an intermediate transfer member. Liquid developed electrophotographic apparatus.

[0002]

2. Description of the Related Art FIG. 4 shows an entire configuration of a conventionally known liquid developing type electrophotographic apparatus (for example, Japanese Patent Application Laid-Open No.
0-055655). After being charged by the charging device 21, the photosensitive drum 10 is exposed by the exposure device 22 to form an electrostatic latent image. The pre-wet device 23 is, for example, a silicone oil
0 surface.

The developing device 24 is provided in association with yellow / magenta / cyan / black, and uses a non-volatile, high-viscosity, high-density liquid toner as a developer. The developing roller supplies the developer onto the photosensitive drum 10 and causes toner particles of the developer to adhere to the photosensitive drum 10 according to an electric field generated between the developing roller and the photosensitive drum 10.

The intermediate transfer roller 15 transfers the color toner adhered to the photosensitive drum 10 one by one according to an electric field between the intermediate transfer roller 15 and the photosensitive drum 10. When the intermediate transfer roller 15 transfers the toner particles adhered to the photosensitive drum 10 in accordance with the electric field between the intermediate transfer roller 15 and the photosensitive drum 10, excessive pre-wet and development that move from the photosensitive drum 10 to the intermediate transfer roller 15 together with the toner particles It is necessary to remove the oil consisting of the carrier in the toner layer. Therefore, in the illustrated apparatus, an oil removing roller 25 is provided on the intermediate transfer roller 15.

The heating device 28 heats the surface of the intermediate transfer roller 15 to melt the toner attached to the intermediate transfer roller 15. The heating by the heating device 28 is performed after transferring the toners of all colors. The pressure roller 19 fixes the toner on the intermediate transfer roller 15 melted by the heating device 28 to the print medium. In the figure, reference numeral 26 denotes a blade for scraping residual toner,
Reference numeral 7 denotes a static eliminator.

The carrier solvent in liquid development is 1 μm
In addition to preventing scattering of the toner particles before and after, it has a function of charging the particles and uniformly dispersing the particles. During the development and electrostatic transfer processes, the toner particles move easily due to the electric field effect. It also plays a role like a bridge.

[0007] The carrier solvent in the liquid developing printer process is a necessary component for toner storage, toner transport / layer formation, development, and electrostatic transfer. However, after the fixing step on the paper medium, the carrier solvent is unnecessary from the viewpoint of image quality and the like. For these reasons, volatile insulating liquids are currently used as carrier solvents for many liquid developers (toners). However, liquid developers using a non-volatile carrier solvent have also been developed due to toner sticking in the device due to carrier volatilization, the effect of the volatile carrier on the human body, and environmental problems. ) Toner.

In the case of a liquid developing toner using a non-volatile carrier solvent, the carrier solvent cannot volatilize the toner when it is heated and melted. In some cases, the development of the adhesive strength is inhibited, and the image quality and the adhesive strength to the paper medium cannot be sufficiently satisfied.

Further, in the method in which the superimposed image on the intermediate transfer member is melt-transferred to a paper medium, the molten toner may be in a state of being spotted on the intermediate transfer member during heating. is there. This is due to the relationship between the releasability of the surface of the intermediate transfer member, the melt viscosity (fluidity) of the toner, and the wettability with the carrier solvent.

As described above, it is necessary to remove the non-volatile carrier solvent as much as possible before the fixing process to the paper medium. However, in the carrier removal before heating, the carrier solvent filled in the gap between the toner particles is removed. Has limitations.

From the above, the "carrier removal during heating" method is effective in which the residual carriers in the toner particles are raised and removed when the toner is heated and melted. The carrier removal method during heating is a method in which a non-volatile carrier solvent remains in a toner image on an intermediate transfer member, and the toner particles (resin component) are integrated and heated when the toner particles are heated and melted. The carrier solvent (liquid component) is separated by utilizing the strong electric field acting force of the toner particles that have been activated. However, when applying an electric field force to the molten toner being heated, it is necessary to consider the influence of the temperature on the roller member and the reciprocal influence on other process conditions. It was not fully considered.

[0012]

SUMMARY OF THE INVENTION The present invention provides a material, a mechanism, and a condition for effectively and stably removing a carrier liquid by further improving such a carrier removal method during heating. It is intended to be.

Another object of the present invention is to perform optimal carrier removal according to the amount of carriers remaining.

[0014]

A liquid developing electrophotographic apparatus according to the present invention uses a liquid toner as a developer and supplies the developer by contacting it on an image support on which an electrostatic latent image is formed.
And according to the electric field generated between the image support,
A developing unit for forming a toner image by attaching toner particles of the developer to the image support; an intermediate transfer member for transferring the toner image on the image support; and a toner transferred to the intermediate transfer member A transfer / fixing unit that heats and melts the image at a contact portion with the print medium and melt-transfers the image onto the print medium. The intermediate transfer member includes an excess carrier removing mechanism having a carrier removing roller for removing excess oil from a toner layer forming an image thereon. The carrier removing roller contacts a toner layer heated to a temperature higher than or close to the melting temperature and applies a bias voltage to the intermediate transfer member holding an image in a direction of pressing toner particles.

Further, the liquid developing electrophotographic apparatus of the present invention comprises:
As an intermediate transfer member, an intermediate transfer roller for transferring a toner image on an image support and superimposing toner images of a plurality of colors, and transferring the toner image superimposed on the intermediate transfer roller at a time to print And an intermediate transfer belt that heats and melts at a contact portion with the medium and melt-transfers to a print medium. Then, the rotation of the intermediate transfer belt is controlled in accordance with the amount of the residual carrier on the intermediate transfer belt holding the heated toner layer.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail according to embodiments. FIG. 1 is a diagram showing a first configuration example of a liquid developing type electrophotographic apparatus embodying the present invention.

First, with reference to FIG. 1, a general outline of a liquid developing electrophotographic apparatus including a transfer and fixing unit, particularly a carrier removing mechanism, which is a feature of the present invention, will be described. A developing unit is provided at the bottom of the apparatus, an intermediate transfer unit is provided thereon, and a transfer fixing unit is provided at the top of the apparatus. An exemplary device is:
As described above, since the transfer fixing unit that generates a large amount of heat is provided at the top of the apparatus, heat can be efficiently discharged from the apparatus. In addition, since the developing unit that handles the liquid toner is provided at the bottom of the apparatus, even if the liquid toner leaks,
The print medium is not easily stained.

The developing section includes yellow / magenta / cyan /
It is provided in association with black. Photosensitive drums (photosensitive members) 11 to 14 are provided, respectively, and a charger for charging the photosensitive drums 11 to 14 to about 700 V is provided (not shown). Exposure indicated by an arrow is performed by charging the charged photosensitive drums 11 to 14 based on image data, for example, 7 times.
This is performed using laser light having a wavelength of 80 nm. As a result, an electrostatic latent image is formed on the photosensitive drums 11 to 14 in which the potential of the exposed portion is about 100 V. Further, a static eliminator (not shown) is provided to eliminate residual potential on the photosensitive drums 11 to 14.

The developing roller is biased to a predetermined voltage such as about 400 V to 600 V, and
4, the positively charged toner is supplied to the photosensitive drums 11 to 14. As a result, toner is adhered to the exposed portions on the photosensitive drums 11 to 14 charged to about 100 V, and the electrostatic latent images on the photosensitive drums 11 to 14 are developed to form images. The toner supply roller includes one or a plurality of rollers for each color toner, and has a toner viscosity of 400 to 4000 mPa · S and a carrier viscosity of 20 to 500 cSt, preferably 100 cSt.
Is conveyed while being spread thinly from the toner pool to apply the liquid toner on the developing roller with a predetermined layer thickness (for example, 4 to 10 μm).

Intermediate transfer roller 1 as first intermediate transfer member
5 are biased to about -800 V, and each photosensitive drum 1
Photosensitive drums 11 to 14 according to an electric field between the photosensitive drums 11 to 14
The toner attached to is transferred. This intermediate transfer roller 1
5 firstly transfers, for example, yellow toner attached to the first photosensitive drum 11, subsequently transfers, for example, magenta toner attached to the second photosensitive drum 12, For example, cyan toner attached to the three photosensitive drums 13 is transferred, and finally, the fourth photosensitive drum 1 is transferred.
For example, the black toner attached to the toner image 4 is transferred. Thus, the first to fourth photosensitive drums 11 to 1
The four-color toner image developed on the intermediate transfer roller 1 is sequentially rotated by rotating the intermediate transfer roller 15 four times.
5 to form a color image. The cleaning blade comes in contact with the intermediate transfer roller at an appropriate timing to remove the toner and the pre-wet liquid remaining thereon.

Thereafter, the four-color image is electrostatically transferred onto the intermediate transfer belt 16 having a belt structure as a second intermediate transfer member, and is transferred after the carrier liquid is removed in the carrier removing section. The toner image is heated and melted at a contact portion with the print medium, and is melt-transferred to the print medium.
The image formed by the liquid toner on the intermediate transfer belt 16 contains a carrier liquid.
This carrier oil is removed.

FIG. 2 is a diagram showing in detail the carrier removing section of the electrophotographic apparatus shown in FIG. As shown, three carrier removing rollers are provided on the intermediate transfer belt 16 so as to contact the heat roller 18.
These carrier removal rollers come into contact with the toner layer on the intermediate transfer belt heated at or near the melting temperature and remove excess oil therefrom. Further, a bias voltage is applied to the carrier removing roller. This bias is applied in a direction in which the toner particles are pressed against the intermediate transfer belt holding the image, for example, +
A voltage of 2 KV is applied. In addition, for transfer fixing,
A bias voltage of −2 KV is applied to the pressure roller 19 with respect to the heat roller. The carrier removal roller
A conductive roller having a resistance value equal to or lower than the electric resistance value of the molten toner, the surface of which is a mirror surface,
That is, it is made smooth. Further, it has both heat resistance to withstand the heating temperature and electric withstand voltage to withstand the applied bias voltage. Further, a blade or the like for collecting the removed carrier is provided. It should be noted that a carrier removing belt having a belt configuration can be used instead of the illustrated carrier removing roller.

The pressure applied to the intermediate transfer belt by a plurality of the carrier removing rollers is, for example,
As the removal of the carrier proceeds in the traveling direction of the intermediate transfer belt 16, the pressing force can be set to be gradually increased. Further, the pressure applied to the carrier removing roller can be adjusted based on the analysis result of the print pattern.

The bias voltage applied to the heat roller 18 of the plurality of carrier removing rollers and therefore to the intermediate transfer belt is set to a voltage value for each roller, for example, as the conductivity of the toner increases as the carrier is removed. Can be lower. The bias voltage applied to the carrier removing roller can be adjusted based on the analysis result of the print pattern.

As for the hardness of the plurality of carrier removing rollers, a hard roller can be used for each roller, for example, as the carrier is removed.

The surface roughness of the plurality of carrier removing rollers can be made more mirror-finished for each roller, for example, as the carrier is removed. It is desirable to arrange the roller so as to rotate the roller in a direction such that the image is not destroyed by the polishing degree of the roller at the time of finishing.

[0027] The apparatus further comprises means for heating the roller by providing a heater inside the carrier removing roller, and means for detecting the temperature of the carrier removing roller, so as to control the carrier removing roller at a constant temperature. This makes it possible to stably remove the carrier while keeping the electric resistance of the carrier removing roller constant.

The toner image on the intermediate transfer belt 16 is heated and melted by a heat roller 18 and is transferred and fixed to a print medium by a pressure roller 19 having a built-in heater cooperating with the heat roller 18.

The transfer / fixing section comprises the above-mentioned pressure roller 19, a plurality of transport rollers, an electrostatic belt wound around the roller, and the above-mentioned intermediate transfer belt 16.
The electrostatic belt adsorbs and transports the print medium by electrostatic force. The heating by the heat roller 18 improves the carrier removal efficiency and cooperates with the pressure roller 19 with a built-in heater to melt the toner image on the intermediate transfer belt 16 and perform transfer and fixing to a print medium. It is. Thereafter, the intermediate transfer belt 16 thus heated needs to be cooled. This is, for example, the intermediate transfer belt 16
Can be performed by cooling a roller (cooling roller) around which is wound. Cooling is performed when toner is transferred from the intermediate transfer roller 15 to the intermediate transfer belt 16 to prevent the occurrence of transfer failure due to the melting of the toner, and to apply heat to the intermediate transfer roller 15. This is to prevent the transmission.

The speed of the intermediate transfer belt 16 during the melt transfer can be controlled, for example, increased, by using the time for superimposing the toner images of a plurality of colors on the intermediate transfer roller 15 within a range that does not affect the throughput. Becomes Further, by controlling the speed of the intermediate transfer belt 16, it is possible to control the toner image to rotate a plurality of times from the time when the toner image is transferred from the intermediate transfer roller 15 to the intermediate transfer belt 16 until the time when the toner image is melt-transferred to the print medium. Can be. As a result, the carrier can be removed a plurality of times by the same carrier removing roller without lowering the throughput.

Further, a means for monitoring the number of rotations of the intermediate transfer belt 16 and changing a bias voltage applied to the carrier removing roller according to the number of rotations can be provided. As the rotation progresses and the carrier is removed,
The optimum applied bias voltage will be different. Therefore,
An optimal bias voltage is set according to the rotation speed.

Further, a means for monitoring the number of rotations of the intermediate transfer belt 16 and changing the pressure applied to the carrier removing roller according to the number of rotations can be provided. As the rotation proceeds and the carrier is removed, the optimum applied pressure will differ. Therefore, an optimal applied pressure is set according to the number of rotations.

Further, the state of the toner image on the fused intermediate transfer belt is detected, and when a large amount of carrier liquid remains, the intermediate transfer belt 16 is provided in a larger amount than in the normal sequence.
To rotate. That is, the number of times of passing through the carrier removing roller can be increased by idling. Therefore, the intermediate transfer belt 16 holding the heated toner layer
The upper surface potential is detected by a surface voltmeter, the amount of residual carriers on the belt is determined from a table describing the relationship, and when the amount of residual carriers is large, the sequence can be changed to a sequence in which the intermediate transfer belt rotates twice. it can. Further, in order to determine the amount of the residual carrier, a reflection type optical sensor for detecting the gloss is provided on the intermediate transfer belt holding the heated toner layer so as to make the incident angle and the reflection angle of light coincide with each other. The residual carrier amount can be determined using the output.

A plurality of carrier removing rollers are brought into contact with each other,
In addition, each carrier removing roller is configured to be independently contactable and retractable, and the total number of contact of the carrier removing roller is finely controlled in consideration of the number of rotations of the intermediate transfer belt according to the residual carrier amount. Can be.

The carrier removing roller made of semiconductive rubber or the like is configured to retract the carrier removing roller from the intermediate transfer belt 16 outside the printing area or during non-printing, in order to prevent a change in resistance value due to a partial temperature rise. You.

Further, in order to stably maintain the electrical characteristics (eg, resistance value) of the carrier removing roller, it is necessary to maintain the carrier removing roller at a constant temperature. for that reason,
The temperature of the carrier removing roller is controlled by having a heater heat source. For example, the carrier removing roller has a hollow pipe roller structure, a halogen lamp heater is built in the pipe roller, a temperature detection sensor is provided on the roller surface, and the heater is turned on and off at a constant temperature, for example, 70 to 80 ° C. be able to. If the carrier removing roller is not provided with a heater heat source, the heated intermediate transfer belt 1
6, the temperature of the carrier removing roller can be raised to a constant value by heat conduction by the driven rotation. In this case, it is desirable to provide a temperature sensor for temperature detection on the surface of the carrier removing roller.

As a method of monitoring the resistance value of the carrier removing roller, a cleaned intermediate transfer belt 16 is used.
It is possible to calculate the resistance value from the voltage and current value when a voltage is applied to the intermediate transfer belt 16 by bringing the carrier removal roller into contact with the upper portion, and perform heating control so that the resistance value falls within a predetermined range. it can.

In a method using one or more carrier removing rollers, the temperature of the final carrier removing roller is
It is desirable to set the temperature higher than the temperature of the intermediate transfer belt 16. The carrier liquid tends to seep from the hot side to the cold side. Therefore, by setting the temperature of the final carrier removing roller higher than that of the intermediate transfer belt 16,
The residual carrier liquid leaks out between the intermediate transfer belt 16 and the molten toner layer to serve as a release material, thereby preventing poor transfer.

In the case of a full-color printer, the transfer bias voltage applied to the intermediate transfer belt 16 may be different between the case of single color printing and the case of overlay printing of two or more colors. Since the potential difference (electric field strength) with respect to the intermediate transfer belt 16 is important for the carrier removal bias on the intermediate transfer belt 16, the carrier removal bias voltage corresponding to the number of superimposed colors of the toner images on the intermediate transfer belt 16,
For example, 1 KV is applied in the case of single-color printing, and 1.5 KV is applied in the case of two-color superposition printing.

The current flowing from the carrier removing roller to which the bias voltage has been applied flows to the intermediate transfer belt 16, and as a result, the potential of the intermediate transfer belt 16 may fluctuate. May have an effect. Therefore, the method of applying a bias voltage to the carrier removal roller is controlled by limiting the current so as not to flow more than necessary, for example, 1 mA or more.

The blade for scraping the carrier liquid from the carrier removing roller may have a plurality of convex protrusions on the lower side in the direction of gravity. FIG. 3 shows the carrier removing roller, the blade tip contacting the lower side thereof, and the carrier liquid accumulated therein. By providing the convex protrusions, the carrier liquid adhering to and accumulating on the blade tip can be quickly dropped.

[0042]

According to the present invention, there is a limit to the removal of the carrier solvent filled in the gaps between the toner particles in the carrier removal before heating. However, the present invention relates to a toner layer heated at or above the melting temperature. A bias voltage is applied to the intermediate transfer member holding the image in a direction in which the toner particles are pressed, so that the excess carrier is sufficiently and reliably removed without disturbing the toner image. be able to.

Further, the present invention has an effect that optimal carrier removal can be performed according to the residual amount of carriers.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first configuration example of a liquid developing type electrophotographic apparatus embodying the present invention.

FIG. 2 is a view showing in detail a carrier removing section of the electrophotographic apparatus shown in FIG.

FIG. 3 is a diagram illustrating a blade configuration for scraping a carrier liquid from a carrier removing roller.

FIG. 4 shows an overall configuration of a conventionally known liquid developing type electrophotographic apparatus.

[Explanation of symbols]

 Reference Signs List 10 photosensitive drum 11 first photosensitive drum 12 second photosensitive drum 13 third photosensitive drum 14 fourth photosensitive drum 15 intermediate transfer roller 16 intermediate transfer belt 18 heat roller 19 pressurizing roller 21 charging device 22 exposure device 23 pre Wet device 24 Developing device 26 Blade 27 Static elimination device 28 Heating device

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) G03G 15/24 G03G 15/10 113 2H078 (72) Inventor Shigenori Uesugi 98 2 PFU Co., Ltd. (72) Inventor Satoru Honoka 98 Unouki-nu, Unoki-cho, Hebei-gun, Ishikawa Prefecture 2 PFU Co., Ltd. (72) Inventor Masanao Takahata 98-Unoki-nu, Unoki-cho, Kawakita-gun, Ishikawa 2 PFU Co., Ltd. (72) Inventor Genji Ichida 98 Uno-cho, Unoki-cho, Kawakita-gun, Ishikawa Prefecture 2 Pfu Co., Ltd. (72) Inventor Shigeharu Okano 98 Uno-kinu, Unoki-cho, Kawakita-gun, Ishikawa Prefecture No. 2 Inside PFU Co., Ltd. (72) Inventor Yasukazu Takeda 98, Unoki-nu, Unoki-cho, Hebei-gun, Ishikawa Pref. Inside (72) Inventor Tadashi Nishikawa 98, Unoki-nu, Unoki-cho, Kawakita-gun, Ishikawa No. 2 P.E. U-uchi (72) Inventor Satoshi Miyamoto 98 Uno-ki-nu, Unoki-cho, Kawakita-gun, Ishikawa Pref. Inside PFU (72) Inventor Satoshi Sakai 98, Unoki-nu, Unoki-cho, Hebei-gun, Ishikawa Prefecture Inside PFU Co., Ltd. (72) Hironaga Motokawa 98, Unoki-nu, Unoki-cho, Kawakita-gun, Ishikawa 2 PFU Co., Ltd. (72) Inventor Masanobu Motoe 98, Unoki-nu, Unoki-cho, Hebei-gun, Ishikawa Pref. F-term Co., Ltd. F-term (reference) 2H032 AA14 BA09 BA21 2H033 BA24 BE09 2H074 AA03 BB42 BB58 BB60 CC11 CC12 CC13 CC21 2H078 BB01 CC06 DD39 DD41 DD51 DD57

Claims (25)

[Claims] 1. An image forming apparatus comprising: a liquid toner as a developer; and a developer supplied by contacting an image support on which an electrostatic latent image is to be formed; Accordingly, a developing unit for forming a toner image by attaching toner particles of the developer to the image support, an intermediate transfer unit for transferring the toner image on the image support, and a transfer to the intermediate transfer unit And a transfer fixing unit that melts and transfers the formed toner image to a print medium by heating and melting the toner image at a contact portion with the print medium. An excess carrier removal mechanism for removing the excessive oil, the excess carrier removal mechanism is in contact with the toner layer heated at or above the melting temperature or near the melting temperature, and at the intermediate transfer portion holding an image, Toner particles Liquid developing electrophotographic apparatus composed of semi-conductive carrier removing roller or belt by applying a bias voltage in a direction to press. 2. The intermediate transfer section comprises a heat roller for heating and melting the transferred toner image to melt-transfer the toner image onto a print medium, and an intermediate transfer belt wound on the heat roller. 2. The liquid developing electrophotographic apparatus according to claim 1, wherein a plurality of rollers are arranged so as to contact the heat roller. 3. The liquid developing electrophotographic apparatus according to claim 2, wherein the pressure applied to the plurality of carrier removing rollers against the intermediate transfer belt is set for each roller. 4. The liquid developing electrophotographic apparatus according to claim 2, wherein a bias voltage applied to the intermediate transfer belt by the plurality of carrier removing rollers is set for each roller. 5. The liquid developing electrophotographic apparatus according to claim 2, wherein the hardness of the plurality of carrier removing rollers is set for each roller. 6. The liquid developing electrophotographic apparatus according to claim 2, wherein a surface roughness of said plurality of carrier removing rollers is set for each roller. 7. The liquid developing electrophotographic apparatus according to claim 3, wherein the pressure applied to the carrier removing roller is adjusted based on a print pattern analysis. 8. The method according to claim 4, wherein the bias voltage applied to the carrier removing roller is adjusted based on a print pattern analysis.
3. The liquid developing electrophotographic apparatus according to item 1. 9. The liquid developing electrophotographic apparatus according to claim 2, wherein the carrier removing roller is arranged in a direction in which an image is not destroyed by a polished edge of the roller. 10. An electric resistance of the carrier removing roller by controlling the carrier removing roller to be maintained at a constant temperature, further comprising a means for heating the carrier removing roller and a means for detecting the temperature of the carrier removing roller. The liquid developing electrophotographic apparatus according to claim 1, wherein the carrier is removed stably to stably remove the carrier. 11. The intermediate transfer section includes an intermediate transfer roller for transferring a toner image on the image support and superimposing toner images of a plurality of colors, and a toner image superimposed on the intermediate transfer roller. Transfer at a time, and an intermediate transfer belt that is heated and melted at a contact portion with the print medium and melt-transferred to the print medium, using a time for superposing all the toner images of a plurality of colors on the intermediate transfer roller. hand,
2. The liquid developing electrophotographic apparatus according to claim 1, wherein the speed of the intermediate transfer belt during fusion transfer is controlled within a range that does not affect the throughput. 12. Controlling the speed of the intermediate transfer belt so that the toner image is rotated a plurality of times from the time when the toner image is transferred from the intermediate transfer roller to the intermediate transfer belt until the time when the toner image is melt-transferred onto the print medium. A liquid developing electrophotographic apparatus according to claim 11. 13. A means for monitoring the number of rotations of the intermediate transfer belt and changing a bias voltage applied to the carrier removing roller according to the number of rotations.
3. The liquid developing electrophotographic apparatus according to item 1. 14. The liquid developing electrophotographic apparatus according to claim 12, further comprising means for monitoring the number of rotations of the intermediate transfer belt and changing the pressure applied to the carrier removing roller according to the number of rotations. 15. An intermediate transfer unit, comprising: an intermediate transfer roller for transferring a toner image on the image support and superimposing toner images of a plurality of colors; and a toner image superimposed on the intermediate transfer roller. Transfer at a time, and heat-melt at a contact portion with the print medium and melt-transfer to the print medium, and detect the surface potential on the intermediate transfer belt holding the heated toner layer. 2. The liquid developing electrophotographic apparatus according to claim 1, wherein the amount of the residual carrier on the belt is determined from a table describing the relationship, and when the amount of the residual carrier is large, the intermediate transfer belt is controlled to rotate twice. 16. The carrier removing roller is configured to be in contact with a plurality of carriers, and each of the carrier removing rollers is configured to be capable of contacting and retracting independently, and the number of carrier removing rollers to be contacted is controlled according to the amount of residual carrier. Claim 15 configured as described above.
3. The liquid developing electrophotographic apparatus according to item 1. 17. An intermediate transfer unit, comprising: an intermediate transfer roller for transferring a toner image on the image support and superimposing toner images of a plurality of colors; and an intermediate transfer roller for transferring the toner image superimposed on the intermediate transfer roller. Transfer at a time, and an intermediate transfer belt that melts and transfers to the print medium by heating and melting at a contact portion with the print medium, and the incident angle of light on the intermediate transfer belt that holds the heated toner layer and A reflection type optical sensor for gloss detection having the same reflection angle is provided, and the amount of the residual carrier on the intermediate transfer belt is determined from the reflection output.
The liquid developing electrophotographic apparatus according to claim 1, wherein the apparatus is controlled to rotate. 18. The carrier removing roller is configured to be in contact with a plurality of carriers, and each of the carrier removing rollers is configured to be capable of contacting and retracting independently, and the number of carrier removing rollers to be contacted is controlled in accordance with the residual carrier amount. Claim 17 configured as described above.
3. The liquid developing electrophotographic apparatus according to item 1. 19. The carrier removing roller according to claim 1, wherein the carrier removing roller is retracted from the intermediate transfer section outside a printing area or during non-printing time to prevent a change in resistance value due to a partial temperature rise. Liquid developing electrophotographic apparatus. 20. The liquid developing electrophotographic apparatus according to claim 1, wherein the carrier removing roller is driven to rotate by a heated intermediate transfer portion to increase the temperature of the carrier removing roller to a constant value by heat conduction. . 21. A resistance value is calculated from a voltage and a current value when a voltage is applied to the intermediate transfer portion by bringing a carrier removing roller into contact with the intermediate transfer portion, and the resistance value falls within a predetermined range. 21. The liquid developing electrophotographic apparatus according to claim 10, wherein the heating is controlled as described above. 22. The liquid developing electrophotographic apparatus according to claim 1, wherein the temperature of the final carrier removing roller among the one or more carrier removing rollers is set higher than the temperature of the intermediate transfer section. 23. The liquid developing electrophotographic apparatus according to claim 1, wherein the bias voltage applied to the carrier removing roller is changed according to the number of superimposed colors of the toner image on the intermediate transfer section. 24. The method according to claim 1, wherein the bias voltage applied to the carrier removing roller is limited to a low current which does not affect the superposition transfer on the intermediate transfer portion by changing the potential of the intermediate transfer portion. The liquid developing electrophotographic apparatus according to the above. 25. A blade for scraping a carrier liquid from the carrier removing roller, wherein a plurality of convex projections are provided below the gravitational direction, and the carrier liquid adhering to the tip of the blade and dripping quickly is dropped. 2. The liquid developing electrophotographic apparatus according to 1.