JP2008170604A - Development apparatus and development method using liquid developer - Google Patents

Abstract

An object of the present invention is to provide a developing device and a developing method using a liquid developer that can clean a groove portion of an anilox roller as a toner applying roller with a simple configuration and prevent a decrease in the amount of liquid developer applied to the developing roller. And
In a developing device using a liquid developer, a toner pumping roller having a rubber layer on a surface disposed in a liquid developer container, and rotation of the toner pumping roller in contact with or away from the toner pumping roller. The toner application roller in which grooves are finely and uniformly formed on the surface to which the liquid developer is supplied by the liquid developer, and the liquid developer held in the grooves of the toner application roller by the regulating blade are quantified and the quantified liquid developer A developing roller to which the toner application roller is applied, and means for bringing the toner scooping roller into contact with the toner application roller or increasing the contact pressure during cleaning of the toner application roller.
[Selection] Figure 2

Description

  The present invention relates to a developing apparatus and a developing method using a liquid developer in which toner particles composed of a colorant and a resin are dispersed in a carrier liquid using a dispersant.

As a developing device using a liquid developer, a developing device is known in which a thin layer of a liquid developer is formed on a developing roller, and a latent image on a photoconductor is developed with the liquid developer forming the thin layer. In Japanese Patent Laid-Open No. 2002-278295, an anilox roller having a groove formed on a surface thereof as a toner application roller is disposed in a liquid developer container, and the regulating blade is aniloxed so that the quantified liquid developer is held in the groove. A developing device using a liquid developer that forms a thin layer of the liquid developer on the developing roller by applying a quantified liquid developer from the anilox roller to the developing roller in contact with the roller is disclosed. In the publication, a part of the groove formed on the surface of the anilox roller is used to prevent the liquid developer from adhering to and remaining in the groove of the anilox roller to reduce the amount of liquid developer applied to the developing roller. Alternatively, a developing device that entirely coats an amorphous fluororesin is disclosed.
JP 2002-278295 A

  As described in the above-mentioned known example, in a developing device using a liquid developer that uses an anilox roller as a toner application roller, the liquid developer adheres and remains in a groove formed on the surface of the anilox roller. There arises a problem that the amount of liquid developer applied to the developing roller decreases. The image density gradually decreases with a decrease in the amount of liquid developer applied to the developing roller. In order to solve the above-described problem, in the known example, the decrease in the amount of liquid developer applied to the developing roller is mitigated by coating the groove portion formed on the surface of the anilox roller with a fluororesin. However, even if fluororesin coating is applied to the groove as in known examples, the fluororesin coating deteriorates due to long-term use, or peels off and adheres to the groove of the anilox roller and completely prevents the remaining liquid developer. As a result, the amount of the liquid developer applied to the developing roller is reduced, which causes an overall or local density reduction.

  The present invention solves the above-described problems, a developing device using a liquid developer that can clean the groove portion of an anilox roller as a toner application roller with a simple configuration and can prevent a decrease in the amount of liquid developer applied to the development roller, and development It aims to provide a method.

  In order to solve the above problems, the first aspect of the present invention, in a developing device using a liquid developer, a toner pumping roller having a rubber layer on a surface disposed in a liquid developer container, and a contact with the toner pumping roller. Or a toner application roller in which a groove is finely and uniformly formed on a surface to which the liquid developer is supplied by rotation of the toner pumping roller away from the toner, and a liquid developer held in the groove of the toner application roller by a regulating blade And a developing roller to which the quantified liquid developer is applied, and means for bringing the toner scooping roller into contact with the toner application roller or increasing the contact pressure when cleaning the toner application roller. And The liquid developer adhered and remaining in the groove portion of the toner application roller is transferred to the toner scooping roller and cleaned, so that the amount of liquid developer applied to the development roller is kept constant and the image density can be recovered. .

  According to a second aspect of the present invention, in the developing device using the liquid developer according to the first aspect, the surface rubber hardness of the toner scooping roller is lower than the surface hardness of the developing roller. Since the amount of the surface of the drawing roller that bites into the groove portion of the toner application roller is larger than the amount of the surface of the developing roller that bites into the groove portion of the toner application roller, the groove portion of the toner application roller can be efficiently cleaned.

  The third invention is characterized in that in the developing device using the liquid developer of the first or second invention, the surface energy of the toner scooping roller is made larger than the surface energy of the developing roller. By making the surface energy of the pumping roller larger than the surface energy of the developing roller, the toner particles adhering to and remaining on the groove portion of the toner application roller can be easily adsorbed on the surface of the toner pumping roller, and the groove portion of the toner application roller can be efficiently Can be cleaned.

  According to a fourth aspect of the present invention, in the developing device using the liquid developer according to any one of the first to third aspects of the present invention, the toner application roller is provided with means for setting so that the cleaning of the toner application roller is performed during non-image formation. And With this configuration, it is possible to eliminate the influence on image formation.

  According to a fifth aspect of the present invention, in the developing device using the liquid developer according to any one of the first to fourth aspects, voltage applying means for applying a voltage to the toner scooping roller, the toner applying roller, and the developing roller is provided. And the voltage application means includes control means for applying the same voltage to the rollers during normal operation, and for applying a higher voltage to the toner scooping roller than the toner application roller during cleaning of the toner application roller. Features. The toner particles are easily moved and adsorbed to the drawing roller side, and the groove portion of the toner application roller can be efficiently cleaned.

  According to a sixth aspect of the present invention, in the developing device using the liquid developer according to any one of the first to fifth aspects, a cleaning blade is provided on the toner scooping roller. By removing the toner adhering to the surface of the scooping roller by the cleaning blade, it is possible to prevent the cleaned toner from entering the groove portion of the toner application roller again.

  According to a seventh aspect of the present invention, in the developing device using the liquid developer according to the sixth aspect of the present invention, a separation contact means for separating and contacting the cleaning blade to the toner pumping roller is provided, and the separation contact means is provided during normal operation. Is characterized in that the cleaning blade is separated from the toner pumping roller and is brought into contact with the toner pumping roller during the cleaning of the toner application roller. The normal rotation torque of the pumping roller can be reduced, and there is no need to mount an excessively large motor or the like.

  According to an eighth aspect of the present invention, in the developing device using the liquid developer according to any one of the first to seventh aspects of the present invention, the rotation speed during normal operation during cleaning of the toner application roller is included in the means for rotating the toner application roller. A control means for making the operation slower is provided. By reducing the speed, the contact time with the surface of the pumping roller becomes longer, and the toner in the groove portion is easily adsorbed on the surface of the pumping roller.

The ninth invention relates to a developing device using the liquid developer according to any one of the first to eighth inventions,
The toner application roller and the developing roller rotate in a counter direction, and the toner application roller and the toner scooping roller rotate in a follow-up direction. In the configuration in which the toner application roller and the developing roller rotate in the counter direction, the toner is easily fixed to the groove portion by rubbing with the developing roller against the toner application roller. On the other hand, the toner adhering to the groove can be cleaned by rotating the scooping roller with the toner application roller in the rotational direction.

  According to a tenth aspect of the present invention, in a developing method using a liquid developer, a toner pumping roller having a rubber layer on a surface disposed in a liquid developer container, and the toner pumping roller in contact with or away from the toner pumping roller. A toner application roller in which grooves are finely and uniformly formed on the surface to which the liquid developer is supplied by rotation of the roller, and a development roller on which a predetermined amount of liquid developer is applied by a regulating blade that contacts the toner application roller; And when the toner application roller is cleaned, the toner scooping roller is rotated by contacting the toner application roller or increasing the contact pressure.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a main configuration of an image forming apparatus using the developing device of the present invention.

  The intermediate transfer belt 70 is an endless belt stretched around a belt driving roller 82 and a driven roller 85, and is rotationally driven while being in contact with the photoreceptors 20Y, 20M, 20C, and 20K. Four primary transfer units 60Y, 60M, 60C, and 60K including the intermediate transfer belt 70, the primary transfer backup rollers 61Y, 61M, 61C, and 61K and the photoconductors 20Y, 20M, 20C, and 20K are arranged on the intermediate transfer belt 70. The color liquid developer is sequentially superimposed and transferred to form a full color liquid developer image.

  The secondary transfer unit 80 includes a secondary transfer roller 81, an intermediate transfer belt driving roller 82, a secondary transfer roller blade 83, and a secondary transfer roller cleaning liquid recovery unit 84, and is formed on the intermediate transfer belt 70. The liquid developer image or the full color liquid developer image is transferred to a recording medium such as paper.

  A fixing unit (not shown) is a device for fusing a single color liquid developer image or a full color liquid developer image transferred onto a recording medium onto the recording medium to form a permanent image.

  The developing units 50Y, 50M, 50C, and 50K develop the latent image with a yellow (Y) liquid developer, a magenta (M) liquid developer, a cyan (C) liquid developer, and a black (K) liquid developer, respectively. It has a function.

  The developing units 50Y, 50M, 50C, and 50K include developing toner containers 53Y, 53M, 53C, and 53K that store the liquid developers, and toner pumping rollers 90Y, 90M, 90C, and 90K that pump the liquid developer from the developing toner containers. Toner application rollers 51Y, 51M, 51C, and 51K for applying a liquid developer to the development rollers 54Y, 54M, 54C, and 54K, and photosensitive members 20Y, 20M, 20C, and 20K on which latent images are developed by the development rollers Chargers 30Y, 30M, 30C, and 30K, and exposure units 40Y, 40M, 40C, and 40K that form an electrostatic latent image on the charged photoreceptor.

  Since the developing units 50Y, 50M, 50C, and 50K have the same configuration, the developing unit 50K will be described below.

  As shown in FIG. 1, a charging unit 30K, an exposure unit 40K, and a primary transfer unit 60K are mainly arranged along the rotation direction of the photoconductor 20K. The photoconductor 20K includes a cylindrical base material and a photosensitive layer formed on the outer peripheral surface thereof, and can rotate around a central axis. In the present embodiment, the photoconductor 20K rotates clockwise.

  The charging unit 30K is a device for charging the photoconductor 20K. The exposure unit 40K forms a latent image on the photoreceptor 20K charged by the organic EL head.

  The developing unit 50K is a device for developing the latent image formed on the photoreceptor 20K using a black (K) liquid developer. The developing unit 50K will be described later.

  The primary transfer unit 60K is a device for transferring the black liquid developer image formed on the photoreceptor 20K to the intermediate transfer belt 70.

  FIG. 2 is a cross-sectional view showing main components of the developing unit 50K. The developing toner container 53K contains a black liquid developer for developing the latent image formed on the photoreceptor 20K. The liquid developer used in this embodiment is a solid particle having an average particle diameter of 1 μm in which a colorant such as a pigment is dispersed in a thermoplastic resin in a liquid solvent such as an organic solvent, silicon oil, mineral oil, or edible oil. It is a liquid developer that is added with a dispersant and has a high viscosity (about 30 to 10000 mPa · s) with a toner solid content concentration of about 20% and is non-volatile at room temperature.

  From the developing toner container 53K, the liquid developer is supplied to the toner application roller 51K by the toner pumping roller 90K, and the liquid developer having a constant concentration is applied from the toner application roller 51K to the development roller 54K. The toner scooping roller 90K has a metal shaft covered with an elastic member such as rubber, and as shown in FIG. 2, the toner scooping roller 90K and the toner application roller 51K rotate in the following direction. The toner application roller 51K and the developing roller 54K rotate in the counter direction. The toner application roller 51K and the developing roller 54K may be rotated in the follower direction.

  As shown in FIGS. 3A, 3B, and 3C, the toner application roller 51K is an anilox roller in which a spiral groove is finely and uniformly formed on the surface. The groove dimensions are such that the groove pitch is about 130 μm and the groove depth is about 30 μm. A voltage equal to or higher than that of the developing roller 54K is applied to the drawing roller 90K and the toner application roller 51K. The liquid developer quantified by the toner application roller 51K is transferred to the developing roller 54K, and the amount of liquid developer on the developing roller 54K is kept constant. As a fine adjustment, the rotational speed of the toner application roller 51K is finely adjusted so that the image density is constant. The image density is kept constant with reference to the patch on the intermediate transfer belt 70.

  The toner regulating blade 52K is composed of a rubber part made of urethane rubber or the like that contacts the surface of the toner application roller 51K, and a plate made of metal or the like that supports the outer rubber part. As shown in FIG. Contact the surface of the application roller 51K, leave the developer in the groove formed on the surface of the toner toner application roller 51K, scrape off other excess developer, and determine the amount of liquid developer supplied to the development roller 54K Turn into.

  The developing roller 54K is a cylindrical member, and is provided with an elastic body such as conductive urethane rubber, a resin layer, and a rubber layer on an outer peripheral portion of an inner core made of metal such as iron. The developing roller 54K is provided with a developing roller blade 58K and a developing roller cleaning liquid recovery unit 59K. The developing roller blade 58K is made of rubber or the like that contacts the surface of the developing roller 54K, and scrapes and removes the liquid developer remaining on the developing roller 54K. The developing roller cleaning liquid recovery unit 59K is a container that stores the liquid developer scraped off by the developing roller blade 58K.

  The compression roller 55K is a cylindrical member, rotates around the central axis, and includes a conductive resin or rubber layer on the surface layer of the metal roller. As shown in FIG. 2, the rotation direction is clockwise in the direction opposite to the developing roller 54K. A voltage is applied to the compression roller 55K from a voltage application member different from the developing roller 54K, and a potential difference is provided between the two rollers. The compression roller blade 56K is made of rubber or the like that contacts the surface of the compression roller 55K, and scrapes off and removes the liquid developer remaining on the compression roller 55K. The compression roller cleaning liquid recovery unit 57K is a container for storing the liquid developer scraped off by the compression roller blade 56K.

  The photoconductor 20K is a cylindrical member that is wider than the developing roller 54K and has a photosensitive layer formed on the outer peripheral surface thereof, and rotates clockwise around the central axis as shown in FIG. The photosensitive layer of the photoreceptor 20K is composed of an organic photoreceptor or an amorphous silicon photoreceptor.

  The charger 30K is provided upstream of the nip portion between the photoconductor 20K and the developing roller 54K. The charger 30K is applied with a bias having the same polarity as the liquid developer from a power supply device (not shown), and charges the photoconductor 20K. A latent image is formed on the charged photoreceptor 20K by the exposure unit 40K. The formed latent image is developed by the developing roller 54K and is primarily transferred to the intermediate transfer belt 70 in the primary transfer unit 60K.

  Next, the operation of such an image forming apparatus will be described. Subsequently, the developing unit will be described by taking the developing unit 50K of the four developing units as an example.

  The liquid developer in the developing toner container 53K has a solid content concentration of 20%, a viscosity of 30 to 10,000 mPa · s, and the toner particles have a positive charge. The liquid developer is pumped up from the developing toner container 53K by the rotation of the toner pumping roller 90K and supplied to the toner application roller 51K. The toner regulating blade 52K contacts the surface of the toner application roller 51K, leaves the developer in the groove formed on the surface of the toner toner application roller 51K, scrapes off other excess developer, and supplies it to the development roller 54K. The amount of liquid developer to be controlled is regulated. By this regulation, the film thickness of the liquid developer applied to the developing roller 54K is quantified so as to be 6 μm. The liquid developer scraped off by the toner regulating blade 52K falls into the developing toner container 53K due to gravity.

  The developing roller 54K coated with the liquid developer contacts the compression roller 55K downstream of the nip portion with the toner applying roller 51K. A constant voltage of +300 to +500 V under constant voltage control by the developing roller voltage applying means is applied to the developing roller 54K. A voltage equal to or higher than that of the developing roller 54K is applied to the toner drawing roller 90K and the toner application roller 51K from the same voltage applying unit as that of the developing roller 54K. The compression roller 55K is applied with a voltage higher than the voltage applied to the development roller by a compression member voltage application unit different from the development roller voltage application unit of the development roller 54K. Therefore, when the toner on the developing roller 54K passes through the nip with the compression roller 55K, the toner moves to the developing roller 54K side, and only the carrier liquid containing almost no toner particles is collected in the compression roller 55K. As a result, the toner particles are gently coupled to form a film. As a result, the toner moves quickly in the developing unit, and the image density is improved.

  The compression roller 55K rotates in the follower direction at a constant speed with respect to the surface of the developing roller 54K. However, the rotational speed and direction of the compression roller 55K may be different from the rotational speed of the developing roller 54K or may be rotated in the counter direction facing the surface of the developing roller 54K. The compression roller blade 56K contacts the compression roller 55K. However, the compression roller blade 56K may not be provided. In this case, the carrier having a constant film thickness is held on the compression roller 55K, and the carrier amount of the toner layer on the developing roller 54K does not change before and after the nip with the compression roller 55K.

  The photoreceptor 20K uses amorphous silicon, and charges the surface to about +600 V by applying about +5.5 kV to the wire of the corona charger 30K upstream of the nip portion with the developing roller 54K. After charging, a latent image is formed by the exposure unit 40K so that the potential of the image portion becomes + 25V. In the developing nip portion formed between the developing roller 54K and the photoconductor 20K, a bias + 300V applied to the developing roller 54K and a latent image (image portion + 25V, non-image portion + 600V) on the photoconductor 20K are formed. According to the electric field, the toner particles selectively move to the image portion on the photoconductor 20K. Thereby, a toner image is formed on the photoconductor 20K. Since the carrier liquid is not affected by the electric field, it is separated at the exit of the developing nip between the developing roller 54K and the photoconductor 20K, and adheres to both the developing roller 54K and the photoconductor 20K.

  The photosensitive member 20K that has passed through the developing nip portion passes through the nip portion with the intermediate transfer belt 70, and primary transfer is performed. The primary transfer backup roller 61K is applied with a voltage of about −200 V having a polarity opposite to the charging characteristics of the toner particles by the primary transfer voltage applying means 103K, and the toner particles on the photoconductor 20K are primarily applied to the intermediate transfer belt 70. After the transfer, only the carrier liquid remains on the photoconductor 20K. The carrier liquid remaining on the photoconductor 20K is scraped off by the photoconductor blade 21K downstream of the primary transfer unit and collected by the photoconductor cleaning liquid collection unit 22K.

  The toner image primarily transferred onto the intermediate transfer belt 70 by the primary transfer unit 60K is directed to the secondary transfer unit 80. In the secondary transfer unit 80, a voltage of −1000 V is applied to the secondary transfer roller 81, and the intermediate transfer belt drive roller 82 is maintained at 0 V. The toner particles on the intermediate transfer belt 70 are paper or the like. Secondary transferred to a recording medium.

  When an image forming apparatus provided with such a developing device is used, the image density may gradually decrease. As a cause of this, in a developing device using a liquid developer using an anilox roller as the toner application roller 51K, the liquid developer adheres to and remains in the groove formed on the surface of the anilox roller, so that the liquid developer on the developing roller 54K is retained. This is thought to be due to a gradual decrease in the amount of coating. The present invention is characterized by comprising means for cleaning the groove on the surface of the toner application roller 51K made of an anilox roller in order to prevent such a decrease in image density.

  FIG. 4 shows a first embodiment of a developing device using the liquid developer of the present invention. In this embodiment, the developing device is a type in which the toner drawing roller 90K and the toner application roller 51K are in contact with each other. The developing roller 54K uses a urethane shaft having a thickness of 6 mm and a rubber hardness of JIS-A 30 ° as an inner layer on a metal shaft having a diameter of 12 mm, a surface layer having a thickness of 100 μm, a rubber hardness of JIS-A 80 °, and a surface roughness of about Rz = 1 μm. Covered with the containing urethane rubber. The toner drawing roller 90K was formed by coating a metal shaft having a diameter of 12 mm with urethane rubber having a thickness of 4 mm, a rubber hardness of JIS-A 30 °, and a surface roughness of about Rz = 4 μm. The toner application roller 51K is an anilox roller in which a spiral groove is finely and uniformly formed on the surface, and a groove having a groove pitch of about 130 μm and a groove depth of about 30 μm was used. Since the surface rubber hardness of the toner pumping roller 90K is lower than the surface rubber hardness of the developing roller 54K, the amount of the surface of the toner pumping roller 90K that bites into the surface groove of the toner application roller 51K during cleaning becomes relatively large. Increase efficiency. Further, by providing a fluorine-containing urethane rubber layer on the surface of the developing roller 54K, the surface energy of the toner scooping roller 90K is made higher than the surface energy of the developing roller 54K. Therefore, the toner application roller 51K is not transferred to the developing roller 54K. The toner particles adhering to and remaining in the grooves are easily attracted to the toner scooping roller 90K, thereby improving the cleaning efficiency.

  In this embodiment, the toner scooping roller 90K and the toner application roller 51K rotate in the follower direction, and the developing roller 54K and the toner application roller 51K rotate in the counter direction. By rotating the toner drawing roller 90K and the toner application roller 51K in the rotating direction, the toner fixed in the groove of the toner application roller 51K can be easily cleaned. During normal operation, the same voltage application means applies the same voltage of +300 V to the toner drawing roller 90K, the toner application roller 51K, and the development roller 54K. The developing roller 54K and the toner application roller 51K rotate in the counter direction at a contact pressure of 0.1 kgf / cm. The toner application roller 51K and the toner scooping roller 90K are normally in contact with each other to the extent that they are lightly touched (contact pressure 0.02 kgf / cm). When the toner application roller 51K is cleaned during non-image formation, the abutment means including the cam 102K, the compression spring 101K, and the lever 100K is driven to increase the contact pressure of the pumping roller 90K to the toner application roller 51K. The contact pressure is 0.2 kgf / cm) and is rotated around. By increasing the contact pressure between the toner pumping roller 90K and the toner application roller 51K during cleaning, the toner cleaning efficiency of the groove portion of the toner application roller 51K is improved. At the time of cleaning, the same +300 V voltage is applied to the toner drawing roller 90K, the toner application roller 51K, and the developing roller 54K by the same voltage applying unit in the same manner as in the normal time. The image density was recovered by cleaning the toner application roller 51K of the first embodiment.

  FIG. 5 shows a second embodiment of the developing device using the liquid developer of the present invention. In the second embodiment, the configuration of the developing roller 54K, the toner application roller 51K, and the toner scooping roller 90K is the same as that of the first embodiment. In the second embodiment, the toner scooping roller 90K and the toner applying roller 51K normally rotate in the follower direction with a gap of about 0.2 mm, and the developing roller 54K and the toner applying roller 51K have a contact pressure of 0. Rotate in the follower direction at 1 kg / cm. When the toner application roller 51K is cleaned during non-image formation, the separation contact means including the cam 102K, the compression spring 101K, and the lever 100K is driven to bring the pumping roller 90K into contact with the toner application roller 51K (contact pressure 0). .3 kgf / cm), and rotate together to carry out. At this time, the cleaning blade 91K that is normally in a non-contact position with the toner scooping roller 90K contacts the scooping roller 90K by driving the front separating contact means. When the cleaning blade 91K contacts the toner pumping roller 90K during cleaning, the toner adhering to the surface of the toner pumping roller 90K can be removed, and the toner can be prevented from entering the groove of the cleaned toner application roller 51K again. By bringing the cleaning blade 91K into contact with the toner pumping roller 90K only during cleaning, the rotational torque during normal operation can be reduced, and there is no need to mount an excessively large motor or the like. During normal operation, the same +300 V voltage is similarly applied to the toner drawing roller 90K, the toner application roller 51K, and the developing roller 54K by the same voltage application unit. At the time of cleaning, a voltage of +400 V is applied to the toner application roller 51K, and a voltage of +0 V is applied to the toner drawing roller 90K, so that the toner in the groove of the toner application roller 51K moves to the toner drawing roller 90K side and is attracted. This improves the efficiency of cleaning. The image density was recovered by cleaning the toner application roller 51K of the second embodiment.

  The third embodiment of the developing device using the liquid developer of the present invention is the same as the configuration of the second embodiment shown in FIG. 5, but the rotational speed of the toner application roller 51K during cleaning is set to 200 mm / s Change from s to 50 mm / s. By slowing down the rotation speed of the toner application roller 51K during cleaning, the contact time between the surface of the toner application roller 51K and the surface of the toner pumping roller 90K becomes longer, and the toner in the groove tends to be adsorbed to the toner pumping roller 90K side. Efficiency can be improved. The image density was recovered by cleaning the toner application roller 51K of the third embodiment.

It is a figure which shows embodiment of this invention. It is a figure which shows embodiment of this invention. (A) (b) (c) It is a figure which shows embodiment of this invention. It is a figure which shows embodiment of this invention. It is a figure which shows embodiment of this invention.

Explanation of symbols

20Y, 20M, 20C, 20K: photoconductor, 21K: photoconductor blade, 22K: photoconductor cleaning liquid recovery unit, 30Y, 30M, 30C, 30K: corona charger, 40Y, 40
M, 40C, 40K: exposure unit, 50Y, 50M, 50C, 50K: development unit,
51Y, 51M, 51C, 51K: toner application roller, 52K: toner regulating blade, 53Y, 53M, 53C, 53K: development toner container, 54Y, 54M, 54C, 54K: development roller, 55K: compression roller, 56K: compression roller Blade, 57K: Compression roller cleaning recovery unit, 58K: Development roller blade, 59K: Development roller cleaning liquid recovery unit, 60Y, 60M, 60C, 60K: Primary transfer unit, 61Y, 61M, 61C, 61K: Primary transfer backup roller, 70: intermediate transfer belt, 80: secondary transfer unit, 81: secondary transfer roller, 82: belt drive roller, 83: secondary transfer roller blade, 84: secondary transfer roller cleaning liquid recovery section, 85: driven roller, 90Y, 90M, 90C, 90K: Toner pumping low , 91K: a cleaning blade, 100K: Lever, 101K: compression spring, 102K: cam,

Claims (10)

A toner pumping roller having a rubber layer on the surface disposed in the liquid developer container, and a surface on which the liquid developer is supplied by rotation of the toner pumping roller in contact with or away from the toner pumping roller. A toner application roller having a groove portion formed thereon, and a developing roller for quantifying the liquid developer held in the groove portion of the toner application roller by a regulating blade and applying the quantified liquid developer. A developing device using a liquid developer, comprising: means for bringing the toner scooping roller into contact with the toner application roller or increasing a contact pressure during cleaning of the roller. 2. The developing device using a liquid developer according to claim 1, wherein a surface rubber hardness of the toner drawing roller is lower than a surface hardness of the developing roller. 3. The developing device using a liquid developer according to claim 1, wherein a surface energy of the toner scooping roller is larger than a surface energy of the developing roller. The developing device using a liquid developer according to claim 1, further comprising a unit configured to perform cleaning of the toner application roller during non-image formation. Voltage application means for applying a voltage to the toner drawing roller, the toner application roller, and the development roller is provided, and the voltage application means applies the same voltage to each of the rollers during normal operation to clean the toner application roller. 5. The developing device using a liquid developer according to claim 1, further comprising a control unit that applies a higher voltage to the toner drawing roller than the toner application roller. The developing device using a liquid developer according to claim 1, wherein a cleaning blade is provided on the toner drawing-up roller. Separating and abutting means for separating and abutting the cleaning blade from the toner pumping roller is provided, and the separating and abutting means separates the cleaning blade from the toner scooping roller during normal operation and the toner application roller during cleaning. The developing device using a liquid developer according to claim 6, wherein the developing device is brought into contact with a drawing-up roller. The liquid developer according to any one of claims 1 to 7, wherein the means for rotating the toner application roller is provided with a control means for making the toner application roller slower than a rotation speed during normal operation when cleaning the toner application roller. Developing device used. The liquid developer according to claim 1, wherein the toner application roller and the developing roller rotate in a counter direction, and the toner application roller and the toner scooping roller rotate in a follow-up direction. Developing device using. A toner pumping roller provided with a rubber layer on the surface disposed in the liquid developer container, and a surface on which the liquid developer is supplied by rotation of the toner pumping roller in contact with or away from the toner pumping roller. A toner application roller having a uniform groove formed thereon; and a developing roller to which a predetermined amount of liquid developer is applied by a regulating blade that contacts the toner application roller; and when the toner application roller is cleaned, the toner pumping roller A developing method using a liquid developer, wherein the toner is rotated while being in contact with the toner application roller or increasing the contact pressure.

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