JP2003066806A - Wet image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wet image forming device which can suppress the formation of liquid rings from both the end parts of a blade and is adaptive to a tandem type full-color machine. SOLUTION: The wet image forming device has a cleaning blade which is so provided as to contact and leave the surface of a photosensitive body and cleans the surface of the photosensitive body and forms an image by using a liquid developer; and the wet image forming device is equipped with air blowing means 25a and 25b which are directed from both the end parts of the cleaning blade 13 to the center part and blow air to a part abutting against the surface of the photosensitive body, and the air blowing means blow the air continuously throughout the image formation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet image forming apparatus using a liquid developer.

[0002]

2. Description of the Related Art In a conventional wet electrophotographic image forming apparatus, a cleaning blade provided on the surface of a photosensitive drum so as to be brought into contact with and separated from the surface of the photosensitive drum is used to collect untransferred excess toner on the photosensitive drum. Further, there is also a unit in which a fur brush, a sponge roller or the like is added as an additional function.
In the dry toner method, the toner collected by the blade does not spread from the effective width of the blade to the outside, even if scattered. However, in the liquid development type cleaning blade, the collected excess toner first spreads to the full width of the blade due to the capillary phenomenon. Next, because of the thickness of the blade, it flows to both sides separately from the collecting direction. As a result, the liquid flows from the both ends of the blade to the surface of the photosensitive drum. This state is called a "liquid ring" because the liquid forms a ring on the surface of the photosensitive drum.

A defect of the liquid ring is that it occurs over the entire circumference of the surface of the photosensitive drum, and therefore has some influence on all units installed around the photosensitive drum. If the amount of the liquid ring increases, it may drop and drop. Then, because of such a defect, what is conventionally taken in the construction of the machine is as shown in FIG. 9, the width of the photosensitive drum 61 is widened to obtain an effective image width. Allow a margin (Fig. 9A). The width of the blade 62 is made longer than the width of the photosensitive drum 61, and the liquid ring 63 is moved to both ends of the photosensitive drum (FIG. 9B). In this case, the flange portions 64 at both ends of the photoconductor drum 61 are soiled, so cleaning means for the flange portion and means for recovering from the flange are required. The liquid ring generated at both ends of the blade is returned to the blade position again by auxiliary means such as the side blades 65 to prevent an increase in the amount (FIG. 9C). The means was mainly. In the figure, 66 indicates excess toner. However, the above-described means is merely a measure for how to treat the generated “liquid ring”, and is not a countermeasure from the viewpoint of not generating it.

Further, a full-color machine such as a tandem system causes a more serious problem. Normally, in a tandem type machine, a belt means 71 such as a paper carrying belt or an intermediate transfer belt is used as shown in FIGS. 10 (A) and 10 (B). Since this belt means comes into contact with the photoconductor drum 72, the liquid in the liquid ring 73 on the photoconductor drum adheres thereto. As a result, the liquid ring generated at the same position is the photosensitive drum 72 of the downstream color.
When it comes into contact with the product, it causes color mixing. That is, it is mixed into the cleaning unit via the photoconductor drum 72. Originally, the liquid ring is the liquid that spilled out from the width of the blade (it is easy to think that it does not affect the downstream blade because it is the liquid that protrudes from the blade end, but due to surface tension and capillary phenomenon , The liquid that has passed through the blade wraps around to the back side of the blade), and the generation width is generated from the range narrower than the blade width
The impact on the downstream side cannot be denied. In order to prevent this, if the belt width is narrower than the width of the cleaning blade 74 (the cleaning blade for the fourth color is not shown) that comes in contact with and separates from the photosensitive drum 72, the adhesion can be prevented. However, this time, the liquid ring from the belt cleaning blade 75 becomes a problem. Even in the case of belt cleaning, the liquid ring is generated regardless of whether it is the paper transport belt method or the intermediate transfer belt method, and there is a difference in the amount, and the liquid ring contacts all the photosensitive drum surfaces. Therefore, due to the capillary phenomenon from the contact portion, the developer flows into the image area and mixes the color of the developer through the developing unit in the image effective area (in the case of liquid development, the developing unit is in contact with the photosensitive drum). In the range, there is adhesion of the carrier component.There is a very small amount.Of course, there is a developing solution consisting of toner and carrier that maintains a predetermined concentration in the image area.Dry development with only toner in the image area This is where the carrier is also present outside the image area in the lateral width and the space between the paper, and it is finally collected by the belt cleaning unit. . The transferred toner component of the image portion is recovered is also dry). Since it is a color machine, the colors will be mixed, so I want to avoid it. Therefore, what about when the blade width is made wider than the belt width? Liquid flows into a small thickness of the belt and spills into the back side of the belt, and as a result, the carrying force of the belt decreases, and the original The belt cannot be driven. Then, why not make the drive roller and the photosensitive drum shorter than the belt? In that case, the tension of the belt will not be sufficient, and if there is a part where the tension is not applied, naturally the edge of the roller The strength of the belt corresponding to the part is reduced, and the life is shortened.

[0005]

Therefore, the present invention solves the above-mentioned conventional problems and does not deal with the generated liquid ring, but rather the liquid ring from both ends of the blade. It is an object of the present invention to provide a wet-type image forming apparatus capable of suppressing the occurrence of the above, and capable of supporting a tandem type full-color machine.

[0006]

In order to achieve the above-mentioned object, the invention of claim 1 has a cleaning blade which is provided so as to be capable of contacting and separating from the surface of the photoconductor to clean the surface of the photoconductor, A wet image forming apparatus for forming an image using a developer, comprising a blowing unit that blows air from both ends of a cleaning blade toward a central portion of the cleaning blade, the blowing unit including: It is characterized in that air is continuously blown during image formation. According to the invention of claim 2, in claim 1,
The blower unit is characterized in that the blowing of air is continued for a predetermined time even after the image formation is completed. The invention of claim 3 is
In Claim 1 or 2, the blower means starts an air blowing operation upon receiving an image formation ON signal. According to a fourth aspect of the present invention, in any one of the first to third aspects, the blowing unit ends the air blowing operation at the same time as or earlier than the contact release timing of the cleaning blade to the surface of the photoconductor. .

According to a fifth aspect of the present invention, in the second to fourth aspects, the air blowing unit changes the setting of the air blowing amount during the image formation and after the image formation. According to a sixth aspect of the present invention, in the fifth aspect, the setting value of the air flow rate is A> B, where A is an image forming time during image forming and B is a waiting time after the image forming is completed. Characterize. According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the air blowing unit sets the air blowing port at least upstream of the contact position of the cleaning blade with the surface of the photoconductor. And The invention according to claim 8 is the toner according to any one of claims 1 to 7, which is outside the image effective range on the surface of the cleaning blade and is on the both end sides inside the air blowing point of the air blowing means. Is provided with a bottomed recessed groove. According to a ninth aspect of the present invention, in any one of the first to eighth aspects, the air blowing unit is attached to a supporting member of the cleaning blade. The invention of claim 10 is based on any one of claims 1 to 9,
It is characterized in that a part of the blowing means utilizes the inside of the blade shaft. In the invention described in claims 1 to 10, the photoconductor includes both the photoconductor drum and the photoconductor belt.

According to an eleventh aspect of the present invention, there is provided a cleaning blade for contacting and separating the surface of each photoconductor drum installed in a tandem type full-color machine to clean the surface of the photoconductor drum, and each photoconductor. A wet image forming apparatus for forming an image by using a liquid developer, which has a cleaning blade which is provided so as to be able to come in contact with and separate from the surface of belt means for moving the surface along a drum, and which cleans the surface of the belt means. The cleaning means for cleaning the surface of the photoconductor drum is equipped with a blowing means for blowing air from both ends of the cleaning blade toward the center part of the cleaning blade, and cleaning for cleaning the surface of the belt means. A second feed for blowing air from both ends of the blade toward the center of the blade to contact the surface of the belt means. Comprising means, blowing means and second blowing means during the image formation, characterized in that is adapted to blow air continuously. In the above-mentioned inventions of claims 1 to 11, an air nozzle is preferable as the blowing means.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is applied to a color image forming apparatus of a wet electrophotographic system (hereinafter referred to as a wet color image forming apparatus) which is a tandem full color machine will be described. The outline of the entire apparatus will be described with reference to FIG. This device includes a plurality of photoconductor drums 1 (PC1) that form images of different print colors.
~ PC4) is provided. The intermediate transfer belt 2 is wound around a belt driving roller 3, a facing roller 4, a tension roller 5 and a plurality of idler rollers 6 in a stretched state,
It is provided in contact with the outer periphery of each photoconductor drum 1. The intermediate transfer belt 2 is formed of a rubber layer such as polyurethane and a core that is difficult to expand and contract, and a transfer roller 7 is pressed against the photosensitive drum 1 with the intermediate transfer belt 2 interposed therebetween. The photoconductor drum 1 is provided with an exposure device (not shown). This exposure device is one that emits an optical signal corresponding to image information color-separated by a scanner or the like from a semiconductor laser and scans the laser light onto a photosensitive drum by a polygon mirror that is rotationally driven. It is possible to use a lens provided with a lens for converging and for correcting the surface tilt of the polygon mirror, a mirror for deflecting laser light, and the like.

A developing unit having a charger 10 and a developing roller 11 on the outer circumference of each photosensitive drum 1.
A cleaning blade 13 and a cleaning blade 13 are provided. In addition, the counter roller 4 on which the intermediate transfer belt 2 is stretched is
The next transfer roller 15 is in pressure contact. Furthermore, at the bottom of the device, a paper feed cassette (not shown) for storing the transfer paper of the transfer material,
A paper feed roller (not shown) that intermittently pulls out one by one from that, and a secondary transfer roller that guides the transfer paper guided to the conveyance path.
A registration roller 16 for feeding to 15 is provided. Above the belt drive roller 3, a fixing roller and a press roller (not shown) are rotatably provided in contact with each other, and a paper discharge roller for discharging the transfer paper passing through the fixing roller to a paper discharge tray is provided. .

In such a structure, images having different print colors are formed on the respective photosensitive drums 1. Here, the image forming process for the photoconductor drum PC1 located on the leftmost side will be described, but the image forming process for the other photoconductor drums PC2 to PC4 will not be described because of the same principle. First, the photosensitive drum PC1 is uniformly charged by the charge from the charging charger 10 during rotation. The exposure device is driven based on the image information separated into the first print color, whereby an electrostatic latent image as a latent image is formed on the charged portion of the photoconductor drum PC1. A developing solution is supplied to the electrostatic latent image by the developing unit to form a toner image. Other printing colors are sequentially formed as toner images and are primarily transferred onto the intermediate transfer belt 2.

On the other hand, the transfer paper pulled out by the paper feed roller is kept in a standby state with its front end in contact with the nip portion of the registration roller 16 and rotates in synchronization with the rotational movement of the photosensitive drum PC1. The roller 16 conveys the toner image on the intermediate transfer belt 2 to the transfer sheet by being conveyed to the secondary transfer position of the secondary transfer roller 15. The transfer paper on which the images are transferred is fixed on the transfer paper in the process of being separated from the intermediate transfer belt 2 and conveyed by the fixing roller and the press roller, and is ejected to the paper ejection tray by the paper ejection roller. . In addition, each time the primary transfer is performed, the photoconductor drum PC1
Excess toner attached on the top is removed by the cleaning blade 13. Further, the excess toner attached to the intermediate transfer belt 2 is removed by the belt cleaning blade 17. Here, the developer is a liquid carrier in which toner is dispersed, and specific examples of the liquid carrier include aliphatic hydrocarbons, silicone oils, natural oils, and liquid paraffin.

FIG. 2 is a schematic perspective view showing one of the plurality of photosensitive drums 1 shown in FIG. 1, for example, the photosensitive drum PC1 and a cleaning device attached to it (photosensitive drums PC2 to PC4 other than those shown in FIG. 1). The cleaning device has the same structure), FIG. 3 is a plan view of the same, and FIG. 4 is a partial enlarged side sectional view of the same. The cleaning device includes a cleaning blade 13, a blade shaft 21 for pressing the blade which is attached and rotatable, a cleaning case 22 which is opened only on the side of the photosensitive drum PC1 and covers the blade and the blade shaft, The lower part of the case is composed of an auger (conveying screw) 23 for collecting the excess toner scraped by the blade 13. Blade axis
A solenoid and a return spring for release as shown in FIG. 5 are provided at one end of 21 and the blade 13 can be brought into contact with and separated from the surface of the photosensitive drum PC1 by these solenoids and springs. That is, the blade 13 is brought into contact with the surface of the photosensitive drum by the operation of the solenoid (see FIG.
(Solid line position: pressurization position) and when the solenoid is released, the spring is controlled to separate from the surface of the photosensitive drum (chain line position in FIG. 4: release position).

At positions outside the effective image range on the blade shaft 21, air nozzles 25a and 25b constituting a blowing means are provided, and the air blowing port at the tip thereof is located at the center from both ends of the blade 13 where the liquid ring of the blade 13 is generated. It is fixed to the part via a mounting bracket by a fastener such as a screw. Air nozzle 25
Each of a and 25b has a base end opening to which both end openings of an air pipe 26 are connected, and a central opening of the air pipe 26 to which one end opening of another air pipe 27 is connected, and the other end of the pipe. An air pump 28 is connected to the opening, and air is supplied by the operation of the pump via the pipes 27 and 26 to the air nozzles 25a and 25b.
And can be blown from the air outlet at the tip of the nozzle. With this configuration, the nozzle provided on the blade shaft 21
25a and 25b also move in contact with and separate from the surface of the photosensitive drum PC1 in synchronization with the blade 13.

The fixing portion of the air nozzles 25a and 25b is not particularly limited. Although it is fixed to the blade shaft 21 as a supporting member in the figure, it may be attached to a cleaning case 22 or the like other than the blade shaft 21. The reason why it is attached to the blade shaft 21 is that it has high mechanical rigidity and that the positional relationship between the air nozzle and both ends of the blade when pressurized can be adjusted at the sub-assembly level before incorporation, and precision can be easily obtained.

With such a configuration, the air pump 28 is operated by an ON signal for image formation or the start of rotation of the photosensitive drum 1 as a trigger. By the operation of the air pump 28, air is blown from the air blow ports of the air nozzles 25a and 25b toward both ends of the blade toward the central portion, and the excess toner is scraped off by the blade 13 by the blowing air and spreads to both ends of the blade. Pushed to the center of the blade,
The blade 13 that comes into contact with the surface of the photoconductor drum 1 is collected from the front end edge side through the surface thereof to the case 22 from the rear end side, and is discharged to the outside of the cleaning device by the auger 23.

Therefore, in the conventional wet image forming apparatus, as shown in FIG. 9, the excess toner scraped off by the belt cleaning blade flows out laterally from the both ends of the blade and flows out to the surface of the photosensitive drum. Although the ring phenomenon was occurring, such a thing does not occur.

In the above, the air blown from the air outlets of the air nozzles 25a and 25b is constantly required during image formation. Further, some time is required even after the image formation is completed (after the machine is stopped). The reason is that the excess toner, which was forcibly pushed to the center of the blade by air, returns to both ends due to the capillary phenomenon. However, if the state is maintained as it is for a certain period of time, the amount transmitted through the blade 13 and accumulated at both ends of the blade front end is reduced. Even if the air is cut off in such a state, even if it returns to both ends, it will not run out and drip as it stabilizes in a state of being balanced by the surface tension. Although this time setting varies depending on the toner viscosity, the amount of toner collected, etc., 10 minutes or less will be appropriate as a guide.

The condition of the amount of air blown also changes depending on the amount of collected toner and the viscosity. There is no need to send more air than necessary. A volatile carrier is volatilized voluntarily, and even a non-volatile carrier cannot help scattering the collected toner. During the image formation, excess toner gradually flows to both ends of the blade, so the air pressure needs to be high. However, at the end of image formation, there is no additional toner, and it is sufficient to suppress the outflow of the toner accumulated at both ends of the blade in the lateral direction. In any case, the purpose of blowing air is to prevent excess toner from reaching both ends of the blade, so it is natural that the nozzle position is on the upstream side of the contact position between the blade 13 and the photosensitive drum or belt. Yes, the wind effect needs to be on the tangent.

By the way, it is not preferable that the blade 13 is always in contact with the surface of the photosensitive drum. Blade 13
It is not preferable in terms of quality stability that the compositional deformation and the pressing force of the blade 13 cause a partial concentrated load to be continuously applied to the photosensitive drum or belt means at the same place. Therefore, of course, the cancellation is necessary. Regarding the timing of the air nozzles 25a and 25b in this releasing operation, it is desirable that the air nozzles 25a, 25b be stopped at the same time or at a timing slightly before the releasing. The toner accumulated on the front end of the blade does not completely disappear even if there is some time after the image formation is completed, and remains on the photosensitive drum by releasing the blade. This is because it is not necessary to scrape out the remaining toner with air.

5, 6 and 7 show another embodiment, FIG. 5 is a perspective view thereof, FIG. 6A is an exploded perspective view before attaching the nozzle and the air pipe to the blade shaft, and FIG. Is a cross-sectional view of the blade shaft after attachment, and FIG. 7A is a partially enlarged view of a portion having a bottomed concave groove provided in the cleaning blade,
FIG. 6B is a partially enlarged view showing the relationship between the bottomed groove viewed from the front edge side of the blade and the air blowing point from the nozzle.

In this embodiment, the cleaning blade
A bottomed concave groove 34 on both ends in the length direction outside the effective image range (the maximum range is shown here) on the surface of 33
Is provided so that the excess toner flowing to both ends of the blade is captured from the abutting front edge side. The captured toner is discharged from the groove to the cleaning case 22 from the rear end side through the blade surface. Therefore, as is apparent from FIG. 7, the concave groove 34 has a substantially inverted trapezoidal shape in which the front end edge side that comes in contact with and separates from the surface of the photosensitive drum PC1 has a wide width, and the front end edge side faces the rear end side surface. The depth is gradually reduced, and the joint with the surface is joined with almost no step. In this structure, the air blowing points P of the air nozzles 35a and 35b are directed to both ends of the blade outside the groove 34,
It plays a role of positively pushing the toner, which tends to flow out of the groove 34 by blowing air, into the groove 34.

Further, in this embodiment, the air nozzle 35
The points a and 35b are not directly connected to the air pipe 36, and the blade shaft 31 is used, which is a difference from the above embodiment.
That is, the nozzles 35a and 35b have their base end openings inserted and connected to the through holes 39 provided in the blade shaft 31, while the air pipes 36 arranged so as to follow the blade shaft 31 have openings at both ends thereof. Is inserted into the through hole 39 from the side opposite to the nozzle and connected. Then, while the shaft hole communicating with the one through hole 39 is formed in the blade shaft 31,
The shaft hole, air piping, and air pump are sequentially connected, and the nozzle
Air is sent to 35a and 35b as in the above-described embodiment. In this way, the nozzle 35a,
35b is attached using the blade shaft 31 in order to minimize the displacement amount of the air pipe 36 during the rotation operation (contact and separation) of the nozzle and to secure the strength of the connecting portion with the air pipe 36. This is because I aimed. In the above, by communicating between both through holes 39 by the axial hole provided in the blade shaft 31,
It goes without saying that the air pipe 36 may be eliminated. In FIG. 5, reference numeral 40 is a solenoid for rotating the blade shaft 31, and 41 is a return spring for release.

Similar effects can be expected in the above-mentioned embodiment. That is, when the air is blown from the air outlets of the air nozzles 35a and 35b, the excess toner flowing to both ends of the blade 33 is effectively pushed to the central portion and suppressed. Particularly, in the case of this embodiment, the concave groove 34 is provided, and the toner flowing primarily is captured by the concave groove and discharged. When the toner flows from the groove 34 to both ends of the blade 33, the air blown from the air nozzles 35a and 35b pushes it toward the groove side, and in any case, the toner is discharged from the groove 34 to both ends of the blade 33. Suppress the flow to the part. Therefore, in this embodiment, the air nozzle 35
There is an advantage that it is not necessary to blow more air than necessary from a and 35b.

FIG. 8 shows the structure shown in FIG.
The part corresponding to (B) is extracted and shown.
Is a partial perspective view thereof, and (B) is a plan view thereof. As is clear from the figure, a cleaning blade 17 is provided for cleaning the surface of the intermediate transfer belt 2 as a belt means so that the cleaning blade 17 can be brought into contact with and separated from the surface. Air nozzles 56a and 56b for blowing air toward the center of the intermediate transfer belt 2 are provided at the contact portion with the surface of the intermediate transfer belt 2 to prevent the generation of a liquid ring on the intermediate transfer belt 2. The air nozzles 56a and 56b also continuously blow air during image formation, continue the blowing of the air for a predetermined time after the image formation is completed, and start the air blowing operation in response to an image formation ON signal. Is similar to the air nozzles 25a and 25b. 8A and 8B and the conventional FIG.
As is clear from the comparison with (A) and (B), the air nozzle
It can be seen that the one provided with 25a, 25b and the air nozzles 56a, 56b can suppress the generation of the liquid ring. Therefore, those provided with the air nozzles 25a and 25b and the air nozzles 56a and 56b can reduce the mechanical allowance in the lateral direction and have a small width. This is the same for a monochromatic machine. The intermediate transfer belt 2 as the belt means is an example, and may be a paper transport belt.

In the above-described embodiment, the air nozzles 25a, 25b, 35a, 35b, 56a, 56b are shown as the air blowing means, but this is merely a preferable example, and it has the same function. Other than the air nozzle may be used. In addition, the air nozzles 25a, 25b, 35a, 35b, 56
The support mechanisms for a and 56b are not limited to those shown in the figures, and can be changed to various ones in practice.

[0027]

According to the first aspect of the present invention, since the cleaning blade has the above-mentioned structure, air is blown from the air blowing means to the contact portion of the cleaning blade toward the center of the surface of the photosensitive member. It is possible to suppress the occurrence of a liquid ring, which is a unique problem in the conventional wet image forming apparatus.
In addition, although adding an air blowing mechanism that is an air blowing mechanism increases the apparent cost, the depth dimension of the machine can be suppressed to a small amount, and the total cost can be reduced.

According to the second aspect of the present invention, the exudation of the liquid generated after the image formation is completed can be prevented. According to the invention of claim 3, by controlling the start timing of the blowing operation, it is possible to consider efficient blowing and energy saving. According to the invention of claim 4, the end timing of the air sending is regulated in relation to the blade release, so that the stability of the remaining toner state can be secured. According to the fifth aspect of the present invention, it is possible to consider efficient blowing and energy saving by changing the setting of the blowing amount during and after the image formation. According to the sixth aspect of the present invention, the required air amount is set to be larger in the former than in the latter at the time of image formation and at the time of standby after the image formation is completed. The invention of claim 7 enables efficient use of air. Claim 8
According to the invention of claim 1, by utilizing the concave groove for capturing the toner, it is possible to efficiently discharge the excess toner from the blade, and it is possible to effectively reduce the air amount. Claim 9,
The tenth invention can realize the accuracy of piping, strength, and jetting position of air delivery. The invention of claim 11 can be applied to a tandem type full color machine. A tandem type full-color machine has a problem of color mixing compared to a monochrome machine, but the following is caused by color mixing from the blade of the belt means to the first color and transfer of each color from the blade of the photosensitive drum to the belt means. Mixing with other colors can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a photosensitive drum and a cleaning device attached thereto.

FIG. 3 is a plan view of the above.

FIG. 4 is a partially enlarged side sectional view of the above.

FIG. 5 is a perspective view showing another embodiment.

FIG. 6 (A) is an exploded perspective view of the same nozzle and air pipe before being attached to the blade shaft, and FIG. 6 (B) is a sectional view of the blade shaft after attachment in the same.

FIG. 7 (A) is a partially enlarged view of a portion having a bottomed concave groove provided on the above cleaning blade, and FIG. 7 (B) shows a bottomed concave groove viewed from the front edge side of the blade and an air blowing point from a nozzle. It is a partially enlarged view showing the relationship of

FIG. 8 is a view showing a portion corresponding to FIGS. 10A and 10B of the related art extracted from FIG. 1, FIG. 8A being a partial perspective view thereof, and FIG.

9A to 9C are drawings for explaining a conventional liquid ring generation state.

10A and 10B are operation explanatory views corresponding to FIG. 8 in a conventional tandem type full-color machine, in which FIG. 10A is a partial perspective view thereof, and FIG.

[Explanation of symbols]

1 (PC1 to PC4) Photoconductor drum (photoconductor) 2 Intermediate transfer belt (belt means) 3 Belt drive roller 4 Opposing roller 5 Tension roller 6 idler rollers 7 Transfer roller 10 Charger 12 Development unit 13, 17, 33 Cleaning blade 21, 31 blade shaft 22 cleaning case 23 Auger (conveyor screw) 25a, 25b, 35a, 35b Air nozzle (air blower) 26, 27, 36 Air piping 28 Air pump 34 bottomed groove 39 through hole 56a, 56b Air nozzle (second blowing means)

Claims (11)

[Claims] 1. A wet image forming apparatus, comprising a cleaning blade which is provided so as to be capable of contacting and separating from the surface of a photoconductor and which cleans the surface of the photoconductor, and which forms an image using a liquid developer. The cleaning blade is equipped with a blowing unit that blows air toward the center of the photosensitive member from both ends of the cleaning blade.The blowing unit continuously blows air during image formation. Characteristic wet image forming apparatus. 2. The wet image forming apparatus according to claim 1, wherein the air blowing unit continues blowing the air for a predetermined time even after the image formation is completed. 3. The wet image forming apparatus according to claim 1, wherein the blowing unit starts an air blowing operation in response to an image formation ON signal. 4. The blower means ends the air blowing operation at the same time as or earlier than the contact release timing of the cleaning blade to the surface of the photosensitive member.
5. The wet image forming apparatus described in any one of 1. 5. The wet image forming apparatus according to claim 2, wherein the air blowing unit changes the setting of the air blowing amount during the image formation and after the image formation. 6. A set value of the air flow rate is A> B, where A is an image forming time during image forming and B is a waiting time after the image forming is completed.
The wet image forming apparatus according to claim 5, wherein the setting is. 7. The wet image forming apparatus according to claim 1, wherein the air blowing means sets the air blowing port at least upstream of the contact position of the cleaning blade with the surface of the photosensitive member. . 8. A bottomed groove for trapping excess toner is provided on both ends of the surface of the cleaning blade outside the effective image range and inside the air blowing point of the blowing means. 5. The wet image forming apparatus described in any one of 1. 9. The wet image forming apparatus according to claim 1, wherein the air blowing unit is attached to a supporting member of the cleaning blade. 10. The wet image forming apparatus according to claim 1, wherein a part of the air blowing means utilizes the inside of the blade shaft. 11. A cleaning blade for contacting and separating the surface of each photoconductor drum installed in a tandem type full-color machine to clean the surface of the photoconductor drum, and a cleaning blade along each photoconductor drum. What is claimed is: 1. A wet image forming apparatus, comprising a cleaning blade which is provided so as to be able to come into contact with and separate from a surface of a belt means for moving the surface and cleans the surface of the belt means, and which forms an image using a liquid developer. A cleaning blade for cleaning the surface of the body drum is provided with a blowing means for blowing air from both ends to a central portion toward the contact portion with the surface of the photosensitive drum, and both ends of the cleaning blade for cleaning the surface of the belt means. A second blower that blows air from the portion toward the center to the contact portion with the surface of the belt means. During the blowing means and the second blowing means are imaging, wet-type image forming apparatus characterized by being adapted to blow air continuously.