JP2011255256A - Image forming apparatus and treatment liquid coating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus the inside of which does not become dirty with liquid dripping caused from a roller end.SOLUTION: The image forming apparatus includes an application roller 232 for applying a treatment liquid 201 to a recording medium and a squeeze roller 233 for thinning a liquid film on the application roller 232. The squeeze roller 233 is controlled to rotate in the same direction as in a coating operation until the treatment liquid 201 retained between the squeeze roller 233 and the application roller 232 becomes a prescribed amount or less after the treatment liquid 201 is applied to the recording medium, and a treatment liquid tray 234 keeps recovering the treatment liquid running down along the rollers from ends of the application roller 232 and the squeeze roller 233.

Description

  The present invention relates to an image forming apparatus and a processing liquid coating apparatus.

  2. Description of the Related Art As an image forming apparatus such as a printer, a facsimile machine, a copying apparatus, a plotter, and a complex machine of these, for example, a liquid ejection recording type image forming apparatus (inkjet recording apparatus) using a recording head that ejects ink droplets is known. . This liquid discharge recording type image forming apparatus means that ink droplets are transported from a recording head (not limited to paper, including OHP, and can be attached to ink droplets and other liquids). Yes, it is also ejected onto a recording medium or a recording medium, recording paper, recording paper, etc.) to form an image (recording, printing, printing, and printing are also used synonymously). And a serial type image forming apparatus that forms an image by ejecting liquid droplets while the recording head moves in the main scanning direction, and a line type head that forms images by ejecting liquid droplets without moving the recording head There are line type image forming apparatuses using

  In the present application, the “image forming apparatus” of the liquid ejection method is an apparatus that forms an image by ejecting liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, or the like. In addition, “image formation” means not only that an image having a meaning such as a character or a figure is imparted to the medium but also an image having no meaning such as a pattern is imparted to the medium (simply liquid. It also means that a droplet hits the medium). The “ink” is not limited to what is called ink, and is not particularly limited as long as it becomes a liquid when ejected. For example, a DNA sample, a resist, a pattern material, etc. Is also included. In addition, the “image” is not limited to a planar one, but includes an image given to a three-dimensionally formed image, and an image formed by three-dimensionally modeling a solid itself. In addition, the “image forming apparatus” is not limited to the liquid discharge type, but includes an apparatus that forms an image using an electrophotographic method.

  In such a liquid ejection type image forming apparatus, in order to form an image by forming ink containing a coloring material into droplets, feathering in which dots formed by the droplets are disturbed, and ink droplets of different colors When the ink is struck on the paper adjacent to each other, it may cause problems such as color bleeding, which causes the colors to mix with each other and the color boundary to become unclear. There is a problem that it takes.

  Therefore, as described in Patent Document 1, a pretreatment liquid that reacts with ink to prevent bleeding is applied by an application roller as described in the prior art, or the pretreatment liquid is ejected as described in Patent Document 2. A mist is applied from the head for application (see also Patent Document 3). An apparatus for applying a treatment liquid in a foam is also known (Patent Document 4).

JP 2002-137378 A Japanese Patent Laying-Open No. 2005-138502 JP 2003-205673 A JP 2009-012394 A

  However, when the processing liquid is applied to the recording medium with a roller, the processing liquid overflows from both ends of the roller when the application state shifts to the non-application state, and the liquid drip into the apparatus occurs. There is.

  The present invention has been made in view of the above problems, and an object of the present invention is to prevent liquid dripping into the apparatus when no processing liquid is applied.

In order to solve the above problems, an image forming apparatus according to the present invention provides:
Image forming means for forming an image on a recording medium;
A coating apparatus for coating a treatment liquid on the recording medium,
The coating device includes:
An application roller for applying a treatment liquid to the recording medium;
A squeeze roller for thinning the liquid film on the application roller;
After the treatment liquid is applied to the recording medium, the squeeze roller is applied during the application operation until the treatment liquid held between the squeeze roller and the application roller falls below a predetermined amount. And a means for controlling the rotation in the direction.

  Here, it can be set as the structure which has the process liquid tray which stores the process liquid supplied to the said squeeze roller and collect | recovered from the said squeeze roller.

  Further, the processing liquid tray may be arranged at a position that always covers the lower part of the application roller and the squeeze roller in an end region of the application roller that does not face the conveyance roller.

  Further, after the processing liquid is applied to the recording medium, the supply of the processing liquid from the processing liquid tray to the squeeze roller is stopped and the squeeze roller is rotated.

Further, when applying the treatment liquid, the application is performed at a position where the valley portion holding the treatment liquid is upward between the application roller and the squeeze roller,
After the treatment liquid is applied, at least one of the application roller and the squeeze roller moves so that a valley portion that holds the treatment liquid is in a horizontal direction, and moves the treatment liquid to the treatment liquid. It can be set as the structure which makes the said processing liquid collect | recovered by the tray and hold | maintained at the said valley part below predetermined amount.

  In this case, the application roller can be moved around the squeeze roller when the trough portion into which the treatment liquid is entrained is moved to a horizontal position.

The treatment liquid coating apparatus according to the present invention is:
A treatment liquid coating apparatus for applying a treatment liquid to a recording medium,
An application roller for applying a treatment liquid to the recording medium;
A squeeze roller for thinning the liquid film on the application roller;
After the treatment liquid is applied to the recording medium, the squeeze roller is applied during the application operation until the treatment liquid held between the squeeze roller and the application roller falls below a predetermined amount. And a means for controlling the rotation in the direction.

  According to the image forming apparatus of the present invention, after applying the processing liquid to the recording medium, until the processing liquid held between the squeeze roller and the application roller becomes a predetermined amount or less, the squeeze roller Is configured to rotate in the same direction as that during the coating operation, so that the processing liquid can be collected when shifting to the non-coating state, and dripping into the apparatus when the processing liquid is not applied can be prevented.

  According to the treatment liquid coating apparatus of the present invention, after the treatment liquid is applied to the recording medium, the squeeze is continued until the treatment liquid held between the squeeze roller and the application roller becomes a predetermined amount or less. Since the roller is configured to rotate in the same direction as that during the application operation, the treatment liquid can be collected when shifting to the non-application state, and dripping into the apparatus when the treatment liquid is not applied can be prevented.

1 is an overall configuration diagram illustrating an example of an image forming apparatus according to a first embodiment of the present invention. It is typical side surface explanatory drawing at the time of the application | coating operation | movement provided for detailed description of the application part of the coating device in the embodiment. It is side sectional explanatory drawing similarly at the time of application | coating operation | movement. It is a perspective explanatory view showing the state at the time of application operation similarly in a permeation state to a processing liquid tray. It is side sectional explanatory drawing similarly at the time of standby. It is a perspective explanatory view at the time of standby similarly. FIG. 2 is an explanatory block diagram for explaining an outline of a control unit of the image forming apparatus. It is a flowchart with which it uses for operation | movement description of the coating device. It is a flowchart with which it uses for description following FIG. It is a flowchart with which it uses for operation | movement description of the coating device in 2nd Embodiment of this invention. 6 is a schematic side explanatory view of a coating portion of Comparative Example 1. FIG. It is a perspective explanatory view of the roller part of the application part of the comparative example 1. It is a plane explanatory view of a roller part similarly. 10 is a schematic side explanatory view of an application part of Comparative Example 2. FIG.

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, an example of an image forming apparatus according to the present invention will be described with reference to FIG. FIG. 1 is an overall configuration diagram of the image forming apparatus.
The image forming apparatus accommodates a recording head unit 101 as an image forming unit that forms an image by ejecting liquid droplets onto a sheet 100 that is a recording medium, a conveyance belt 102 that conveys the sheet 100, and the sheet 100. A paper feed tray 103 and a processing liquid coating apparatus 200 according to the present invention for coating a processing liquid on the paper 100 that is a member to be coated on the upstream side of the recording head unit 101 in the paper transport direction are provided.

  The recording head unit 101 is composed of a line type liquid discharge head having a nozzle row in which a plurality of nozzles for discharging droplets are arranged in a length corresponding to the paper width. Yellow (Y), magenta (M), cyan The recording heads 101y, 101m, 101c, and 101k are provided with ink droplets of each color of (C) and black (K). Note that the recording head can be mounted on the carriage as a serial type image forming apparatus.

  The conveyor belt 102 is an endless belt, and is configured to circulate between the conveyor roller 121 and the tension roller 122. The paper 100 can be held on the transport belt 102 by, for example, a configuration that performs electrostatic suction, suction by air suction, or other known transport means. Further, a conveying means using a roller pair can also be used.

  The sheets 100 stored in the sheet feeding tray 103 are separated and fed one by one by a pickup roller 131 and sent to a registration roller pair 133 by a conveyance roller pair 132. The registration roller pair 133 causes the sheet 100 to be conveyed by a conveyance roller pair 134 at a predetermined timing. It is sent to the coating device 200 via the transport path 135, and the treatment liquid is applied by the coating device 200, and is sent and held on the transport belt 102.

  Then, it is conveyed by the circular movement of the conveyor belt 102, droplets of each color are ejected from the head unit 101, an image is formed, and then ejected to the ejection tray 104.

  The coating apparatus 200 is a recording medium that includes a container 202 containing a processing liquid 201, a pump 203 that pumps the processing liquid 201 from the container 202, and the processing liquid 201 that is supplied by the pump 203 via a supply path 204. And an application unit 208 that applies to the paper 100.

  Here, the treatment liquid 201 is a modifying material that modifies the surface of the paper 100 by being applied to the surface of the paper 100. For example, the treatment liquid 201 is applied in advance to the paper 100 (not limited to paper as a material as described above) without unevenness, so that moisture of the ink can quickly permeate the paper 100 and increase the color component. Fixing agent (setting agent) that prevents bleeding (feathering, bleeding, etc.) and back-through by increasing viscosity and further drying, and increases productivity (number of images output per unit time). is there.

  In terms of composition, this treatment liquid 201 is, for example, cellulose that promotes moisture permeation with respect to a surfactant (any one of anionic, cationic, nonionic, or a mixture of two or more thereof). And a solution to which a base such as hydroxypropyl cellulose and a talc fine powder are added. Furthermore, fine particles can be contained.

  Next, details of the coating unit of the coating apparatus according to the first embodiment of the present invention will be described with reference to FIGS. 2 is a schematic side view illustrating the application portion during the application operation, FIG. 3 is a side cross-sectional explanatory view during the application operation, and FIG. 4 is a state in which the application operation is performed in a transparent state through the treatment liquid tray. 5 is a side cross-sectional explanatory view during the non-coating operation (no application operation is performed), and FIG. 6 is a perspective explanatory view during the non-coating operation.

  The coating unit 208 thins the transport roller 235 that transports the paper 100, the coating roller 232 that applies the processing liquid 201 to the paper 100 so as to face the transport roller 235, and the liquid film of the processing liquid 201 on the coating roller 232. A squeeze roller 233 and a processing liquid tray 234 for supplying and recovering the processing liquid 201 are provided. The rotation direction of each roller is the direction indicated by the arrow in FIG.

  These rollers are arranged such that the application roller 232 is in contact with the conveyance roller 235 and the squeeze roller 233 is in contact with the application roller 232. The squeeze roller 233 is disposed so as to be immersed in the processing liquid 201 in the processing liquid tray 234.

  In the application unit 208, the application roller 232, the squeeze roller 233, and the processing liquid tray 234 are unitized (integrated) to form a roller unit 236. The roller unit 236 includes a driving unit (not shown) (motor to be described later). 516) through a drive transmission mechanism (not shown), the state shown in FIGS. 3 and 4 (referred to as application state or application position), and the state shown in FIGS. 5 and 6 (standby (non-application) state or standby (not yet applied)). It is arranged so as to be swingable (movable) between (applying) positions) (in the direction of arrow A in FIG. 2). 4 indicates a portion where the application roller 232 and the transport roller 235 are in contact with each other corresponding to the opening of the processing liquid tray 234.

  That is, during the application operation for applying the treatment liquid 201 to the recording medium 100, the squeeze roller 233 and the application roller 232 are arranged in contact with each other in contact with the application position shown in FIGS. 3 and 4. The valley portion formed by the rollers 233 and 232 that wind the roller is upward.

  In this application state, the processing liquid 201 is pumped up from the processing liquid tray 234 by rotating the squeeze roller 233, and the processing liquid 201 b is accumulated in the valley portion formed by the squeeze roller 233 and the application roller 232. The processing liquid 201b accumulated in the coating film 232 and the squeeze roller 233 are in pressure contact with each other, so that the processing liquid 201b becomes a thin liquid film when passing through the nip portion (contact portion) between the rollers 233 and 232. Is coated on the recording medium passing between the transport roller 235 and the coating roller 232.

  Further, when the treatment liquid 201 is not applied (at the time of standby), the squeeze roller 233 and the application roller 232 are arranged in the vertical direction and moved to the standby position shown in FIG. 5 and FIG. Since the valley portions formed by 233 and 232 are in the horizontal direction, the processing liquid 201 accumulated in the valley portions falls on the processing liquid tray 234 and is collected by its own weight.

  Here, the treatment liquid tray 234 is always disposed at a position that covers the lower side of the application roller 232 and the squeeze roller 233 in an end region that does not face the conveyance roller of the application roller in both the application position and the standby position. By adopting such an arrangement, the processing liquid can be quickly recovered without contaminating the inside of the apparatus from the end area of the roller where the liquid has accumulated thick because it does not contribute to the application.

Next, an outline of the control unit of the image forming apparatus will be described with reference to FIG.
The main control unit 501 includes a microcomputer including a CPU, ROM, RAM, I / O, and the like that controls the entire image forming apparatus. The main control unit 501 processes the received image data and transfers the processed image data to the print control unit 502. The print control unit 502 controls driving of the recording head 101 via the head driver 503 according to the image data. To eject droplets. In addition, the main control unit 501 drives and controls the conveyance motor 505 that rotates the conveyance belt 102 through the motor driving unit 504 to convey the recording medium 100.

  The application control unit 510 also serves as a control unit in the present invention, and controls each part of the application apparatus 200. In response to a coating request from the main control unit 501, the coating control unit 510 drives the pump 203 through the pump driving unit 511 and controls the coating roller 232 through the roller driving unit 512 in order to control the processing liquid coating operation. The motor 513 that rotates the squeeze roller 233 is driven and controlled, and the motor 516 that swings (rotates) the roller unit 236 via the unit driving unit 515 is controlled.

The operation of the coating apparatus in the embodiment configured as described above will be described with reference to the flowcharts of FIGS.
First, referring to FIG. 8, when an image output (application) request is received, it is determined whether or not the application unit 208 of the application apparatus 200 is in a standby (non-application) state. It is rotated to move the positions of the rollers 232 and 233 to the application state.

  Then, it is determined whether or not there is a predetermined amount of processing liquid 201 in the processing liquid tray 234 (denoted as “liquid tray” in the figure, the same applies hereinafter), and the pump 203 is driven when there is no predetermined amount of processing liquid 201. Then, the processing liquid 201 is supplied (supplemented) from the container 202 (denoted as “tank” in the figure; the same applies hereinafter) to the processing liquid tank 234 until a predetermined amount is reached.

  Thereafter, the coating apparatus 200 is operated, and the squeeze roller 233 and the coating roller 232 of the coating unit 208 are rotated to perform coating on the recording medium. When there are a plurality of requested application numbers and the output of the requested number is not completed, it is determined again whether or not there is a predetermined amount of the processing liquid 201 in the processing liquid tray 234. 203 is driven to supply (replenish) the processing liquid 201 from the container 202 to the processing liquid tank 234 until a predetermined amount is maintained, and the predetermined amount is maintained.

  As shown in FIG. 9, when the output of the required number of sheets is completed, the coating apparatus 200 enters a primary standby state. In this primary standby state, at least the squeeze roller 233 is rotated in the same direction as during application.

  As a result, the processing liquid flowing down from the ends of the application roller 232 and the squeeze roller 233 along the rollers is continuously collected in the processing liquid tray 234. That is, when the rotation of the squeeze roller 233 is stopped in this state, the processing liquid flowing down through the roller is not collected into the processing liquid tray 234 but flows around to the application roller 232 side, and the processing liquid is applied to the surface of the application roller 232. A region to which 201 is attached thickly is formed. However, by continuing to rotate the squeeze roller 233 in this way, the processing liquid reaching the roller end adheres to the squeeze roller 233 and is quickly collected in the processing liquid tray 234, and the processing liquid in the processing liquid tray 234 is recovered. Since it is combined with 201, it is possible to prevent the coating roller 232 from going around.

  In this operation, since the processing liquid is continuously supplied from the processing liquid tray 234 to the valley portion formed by the rollers 233 and 232 by the rotation of the squeeze roller 233, the processing liquid 201b is not exhausted. It is possible to maintain a state that can respond to the next image output request.

  Thereafter, when the next image output (application) request is received within a predetermined time, the above processing is repeated. When the next image output (application) request is not received within the predetermined time, the roller unit 236 is rotated to rotate the roller. The positions of 232 and 233 are moved to the standby state. By doing in this way, the processing liquid 201b in the valley portion formed by the rollers 233 and 232 flows down to the processing liquid tray 234, and the application roller 232 is disposed above the squeeze roller 233. The liquid 201 does not adhere.

  When the rollers 232 and 233 are moved to the standby state, the application roller 232 is moved (rotated) around the squeeze roller 233 with the squeeze roller 233 being rotated until the application roller 232 is positioned above the squeeze roller 233. As described above, if the position is in the standby state, the processing liquid 201b in the valley portion flows down to the processing liquid tray 234, and the processing liquid does not adhere to the coating roller 232. The rotation of 233 may be stopped.

  Further, when the next image output (application) request is received within a predetermined time, the positions of the rollers 232 and 233 are moved again to the application state, and the above processing is repeated.

  When the next image output (application) request is not received within a predetermined time after moving to the standby state, the processing liquid 201 in the processing liquid tray 234 is collected in the container 202.

  As described above, after applying the treatment liquid to the recording medium, the squeeze roller is rotated in the same direction as the application until the treatment liquid held between the squeeze roller and the application roller becomes a predetermined amount or less. By adopting the configuration, it is possible to collect the treatment liquid when shifting to the non-application state, and to prevent dripping into the apparatus when the treatment liquid is not applied.

  Further, when applying the treatment liquid, the application roller and the squeeze roller are in contact with each other and the application is performed at a position where the valley portion where the treatment liquid is wound is upward. When the treatment liquid is not applied, at least the application roller and the squeeze roller One side is moved so that the valley portion into which the processing liquid is entrained is in a horizontal position, and the processing liquid tray is a position that always covers the lower part of the application roller and the squeeze roller in the end region that does not face the conveying roller of the application roller. By adopting the configuration, it is possible to prevent dripping into the apparatus when the processing liquid is not applied, to effectively use the processing liquid, and to reduce deterioration of the rollers.

  That is, at the time of application, the processing liquid 201 is scooped up along the surface of the squeeze roller 233 as described above, and accumulates in a valley portion with the application roller 232. At this time, the processing liquid that has not been used for coating moves along the roller surface, the coating roller 232 side goes around the coating roller and returns to the valley portion, and the squeeze roller side performs processing in the processing liquid tray 234 below. By being immersed in and recovered from the liquid 201, it is reused as a processing liquid.

  Further, when the squeeze roller 233 and the application roller 232 are arranged in the horizontal direction and the application operation is stopped (abnormal state) in the standby state, the process liquid 201 that is not used for application and remains on the application roller 232 side can be returned to the process liquid tray 234. A part not present is accommodated in the liquid tray 250.

  In this way, the processing liquid tray (liquid tray 250) is formed up to a position covering the lower side of the application roller, so that the image forming apparatus is not soiled with the processing liquid even in an abnormal state. The liquid tray 250 is provided only in the end region of the application roller 232 that does not face the conveyance roller 100. Here, since the liquid layer is formed of a thin film in the opposing region, no liquid dripping occurs in a short time, whereas in the end region, the liquid film is thick and liquid dripping occurs in a short stop. Therefore, a sufficient effect can be obtained even if it is provided only in the regions that do not face each other.

  Further, at the time of standby, the squeeze roller 233 and the application roller 232 are arranged in the vertical direction (vertical direction), so that all of the processing liquid 201 remaining on the surface of the squeeze roller 233 and the application roller 232 and the valley portion is placed in the processing liquid tray 234. It can be recovered and reused when the application operation resumes.

  Further, when the application operation is resumed after the application operation is stopped (abnormal state) with the squeeze roller 233 and the application roller 232 arranged in the horizontal direction, the squeeze roller 233 and the application roller 232 are once set to the standby positions (up and down). ), The squeeze roller 233 and the coating roller 232 surface, and all the processing liquid 201 in the valley portion and the processing liquid 201 stored in the liquid tray 250 are collected in the processing liquid tray 234 and applied. Can be reused when operation resumes.

  If the uncoated state continues for a long time, the pump 203 is configured as a reversible pump, or a processing liquid discharge path is added separately, and the processing liquid 201 collected in the processing liquid tray 234 is returned to the container 202. The deterioration of each roller by the processing liquid 201 can be further reduced, and the processing liquid 201 itself can be prevented from being changed.

Here, Comparative Example 1 will be described with reference to FIGS. 11 to 13 and Comparative Example 2 with reference to FIG.
In the first comparative example, the processing liquid 201 in the liquid tray 534 is pumped up by the squeeze roller 233, is made into a liquid film layer 201 a state by the regulating roller 536, and is supplied to the application roller 232 by the squeeze roller 233.

  In the configuration of the first comparative example, the processing liquid 201 transferred from the squeeze roller 233 is accumulated as a processing liquid 201 b in a valley portion between the squeeze roller 233 and the application roller 232. In this state, when the rollers 233 and 232 are stopped in the standby state, the processing liquid 201b accumulated in the valley portion overflows from both ends of the roller as indicated by the liquid 201d, and if this state continues for a long time, the liquid dripping 201g The inconvenience of dropping inside the apparatus occurs.

  In Comparative Example 2, the application roller 232 is disposed above the squeeze roller 233, the transport roller 235 is disposed above the application roller 233, and when the rollers 233 and 232 are stopped, the processing liquid of the rollers 233 and 232 is gravity-induced. In this configuration, the liquid is dropped onto the lower liquid tray 234.

  In the configuration of Comparative Example 2, the processing liquid is applied to the sheet on the lower surface of the sheet. However, when a treatment liquid is applied as a pretreatment for an ink jet recording apparatus or the like, the treatment liquid is preferably applied immediately before printing as much as possible. This is because the reaction between the treatment liquid and the ink can be performed in a liquid state. For this reason, when the treatment liquid is applied by the ink jet recording apparatus, it is usually preferable to apply the treatment liquid to the upper surface of the recording medium. In the configuration of Comparative Example 2, it is not possible to meet the requirement for applying the treatment liquid in such an ink jet recording apparatus.

  Therefore, in the present embodiment, the rollers 233 and 232 are disposed in the horizontal direction when performing the coating operation, the rollers 233 and 232 are disposed in the vertical direction during standby, and the processing liquid tray 234 is always disposed below the roller 233. With this configuration, liquid dripping from the roller end during standby is prevented, and the processing liquid can be collected from the roller.

Next, control of the coating apparatus according to the second embodiment of the present invention will be described with reference to the flowcharts of FIGS.
When the output of the requested number of sheets is completed in FIG. 8, the coating apparatus 200 enters a primary standby state as shown in FIG. In this primary standby state, at least the squeeze roller 233 is rotated in the same direction as during application. As a result, the processing liquid flowing down from the ends of the application roller 232 and the squeeze roller 233 along the rollers is continuously collected in the processing liquid tray 234. At this time, the squeeze roller collects the processing liquid in the processing liquid tray 234 and simultaneously supplies the processing liquid 201 to the valley portion formed by the rollers 233 and 232. By not going to the valley portion, the processing liquid 201b in the valley portion can be reduced.

  Then, it is determined whether or not the recovery of the processing liquid is completed. When the recovery of the processing liquid is completed, the squeeze roller 232 is stopped. Here, whether or not the recovery of the processing liquid is completed may be detected by, for example, the processing liquid before the recovery based on the amount of reflected light of the reflective sensor or the energization state between a plurality of electrode pins. Alternatively, a predetermined time required for collecting the processing liquid may be measured in advance, and it may be determined that the processing liquid has been recovered when the predetermined time has elapsed.

  Thereafter, when the next image output (application) request is received within a predetermined time, the process shown in FIG. 8 is repeated. When the next image output (application) request is not received within the predetermined time, the roller unit 236 is rotated. Thus, the positions of the rollers 232 and 233 are moved to the standby state.

  Further, when the next image output (application) request is received within a predetermined time, the positions of the rollers 232 and 233 are moved again to the application state, and the process shown in FIG. 8 is repeated.

  When the next image output (application) request is not received within a predetermined time after moving to the standby state, the processing liquid 201 in the processing liquid tray 234 is collected in the container 202.

  If comprised in this way, after shifting to a primary standby state, rotation of a squeeze roller can be stopped at an early stage. The wear of the squeeze roller 233 and the application roller 232 can be suppressed, the life of the apparatus can be extended, and the power consumption can be reduced.

  In the above embodiment, the processing liquid coating apparatus is described as applying the processing liquid to the paper before image formation. However, the processing liquid is applied on the paper on which the image is formed on the downstream side of the recording head unit. It can also be set as the structure which apply | coats.

  The image forming apparatus according to the present invention can also be applied to, for example, an electrophotographic image forming apparatus. For example, the resin fine particles are quickly fixed to the medium without disturbing fine particles containing resin such as toner on the medium such as paper, and after applying the fixer to the medium to which the resin fine particles are adhered. In addition, the present invention can also be applied to a fixing method and a fixing device, and an image forming method and an image forming apparatus using a fixing solution of resin fine particles that can be applied in a minute amount so that no residual oil feeling is generated.

100 Recording medium (paper)
DESCRIPTION OF SYMBOLS 101 Recording head unit 102 Conveying belt 103 Paper feed tray 200 Processing liquid application apparatus 201 Processing liquid 208 Application | coating part 232 Application roller 233 Squeeze roller 234 Processing liquid tray 235 Conveyance roller 236 Roller unit

Claims (7)

Image forming means for forming an image on a recording medium;
A coating apparatus for coating a treatment liquid on the recording medium,
The coating device includes:
An application roller for applying a treatment liquid to the recording medium;
A squeeze roller for thinning the liquid film on the application roller;
After the treatment liquid is applied to the recording medium, the squeeze roller is applied during the application operation until the treatment liquid held between the squeeze roller and the application roller falls below a predetermined amount. And an image forming apparatus characterized by comprising: means for controlling rotation in the direction.   The image forming apparatus according to claim 1, further comprising a processing liquid tray that stores processing liquid supplied to the squeeze roller and collected from the squeeze roller.   The image forming apparatus, wherein the processing liquid tray is disposed at a position that always covers a lower portion of the application roller and the squeeze roller in an end region of the application roller that does not face the conveyance roller.   3. The control according to claim 2, wherein after the treatment liquid is applied to the recording medium, the supply of the treatment liquid from the treatment liquid tray to the squeeze roller is stopped and the squeeze roller is rotated. The image forming apparatus according to 3. When applying the treatment liquid, the application is performed at a position where the valley portion holding the treatment liquid is upward between the application roller and the squeeze roller,
After the treatment liquid is applied, at least one of the application roller and the squeeze roller moves so that a valley portion that holds the treatment liquid is in a horizontal direction, and moves the treatment liquid to the treatment liquid. The image forming apparatus according to claim 2, wherein the processing liquid collected in a tray and held in the valley portion is set to a predetermined amount or less.   The image forming apparatus according to claim 5, wherein the application roller is moved around the squeeze roller when the valley portion into which the processing liquid is entrained is moved to a horizontal position. A treatment liquid coating apparatus for applying a treatment liquid to a recording medium,
An application roller for applying a treatment liquid to the recording medium;
A squeeze roller for thinning the liquid film on the application roller;
After the treatment liquid is applied to the recording medium, the squeeze roller is applied during the application operation until the treatment liquid held between the squeeze roller and the application roller falls below a predetermined amount. And a means for controlling the rotation in the direction.

Images