Inkjet recording device

Abstract

To provide an inkjet recording device capable of restricting discharge failure and image disturbance that are caused when treatment liquid and ink agglomerate in a head.SOLUTION: An inkjet recording device 1 comprises: a conveyance unit 3 for conveying a recording medium M in a conveyance direction; and an image formation unit 4 for forming an image on the recording medium M by discharging ink in accompany with scanning in a width direction crossing the conveyance direction. The image formation unit 4 comprises: an ink discharge unit 42 including inkjet heads 421 for discharging ink; a treatment liquid discharge unit 43 including a treatment liquid discharge head 431 for discharging treatment liquid that causes ink to agglomerate; an air current generation unit 44 for generating an air current in a height direction crossing the conveyance direction and the width direction; and an air current adjustment unit for making adjustments so that a flow rate of passing gas is larger on a treatment liquid discharge unit 43 side than on an ink discharge unit 42 side, using a gap between the ink discharge unit 42 and the treatment liquid discharge unit 43 as a boundary.SELECTED DRAWING: Figure 3B

Description

Technical Field

[0001] The present invention relates to an inkjet recording apparatus.

Background Art

[0002] Conventionally, an inkjet recording apparatus including an inkjet head that forms an image on a recording medium by ejecting ink from nozzles has been known. In the inkjet recording apparatus, there is a device that applies a treatment liquid for aggregating the ink to the recording medium in order to retain the ink on the surface of the recording medium. Among them, there is an in-line type inkjet recording apparatus that includes a treatment liquid ejection head for ejecting the treatment liquid and ejects the treatment liquid simultaneously with the ink onto the conveyed recording medium. However, when the treatment liquid and the ink are ejected simultaneously, mist of one may adhere to the other head to form an aggregate, and ejection failure may occur in the other head.

[0003] In response to such problems, for example, Patent Document 1 describes a printing apparatus provided with a plasma actuator on the head. The plasma actuator is intended to suppress the adhesion of mist to the head and suppress ejection failure by generating an air flow with respect to the platen gap.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the invention of Patent Document 1, the mist is scattered by the air flow generated by the plasma actuator. As a result, not only is it impossible to suppress the adhesion of the mist to the nozzles, but the accurate landing of the ink is hindered, which may cause image disturbance.

[0006] The present invention has been made in view of such circumstances. Its object is to provide an inkjet recording apparatus capable of suppressing ejection failure and image disturbance caused by aggregation of a processing liquid and ink at a head.

Means for Solving the Problems

[0007] In order to solve the above problems, the invention according to claim 1 is an inkjet recording apparatus, a conveyance unit that conveys a recording medium in a conveyance direction, an image forming unit that forms an image on the recording medium by ejecting ink along with scanning in a width direction orthogonal to the conveyance direction, the inkjet recording apparatus comprising: the image forming unit includes an ink ejection unit having an inkjet head that ejects ink, a processing liquid ejection unit having a processing liquid ejection head that ejects a processing liquid for aggregating the ink, an airflow generation unit that is provided at least between the ink ejection unit and the processing liquid ejection unit and generates an airflow in a height direction orthogonal to the conveyance direction and the width direction, an airflow adjustment unit that adjusts so that the flow rate of the gas passing through the processing liquid ejection unit side is larger than that of the ink ejection unit side with the boundary between the ink ejection unit and the processing liquid ejection unit.

[0008] The invention according to claim 2 is the inkjet recording apparatus according to claim 1, wherein the processing liquid ejection head is provided outside the ink ejection unit.

[0009] The invention according to claim 3 is the inkjet recording apparatus according to claim 1, wherein the airflow adjustment unit includes a portion where a gap between at least a part of the processing liquid ejection unit and the recording medium is larger than a gap between the ink ejection unit and the recording medium.

[0010] The invention according to claim 4 is the inkjet recording apparatus according to claim 1, The airflow generating unit includes an intake device that sucks gas from the recording medium side and an air supply device that supplies gas to the recording medium side. The airflow adjusting unit includes the intake device and the air supply device, and is provided on both sides adjacent to the width direction of the processing liquid discharge unit.

[0011] The invention according to claim 5 is an inkjet recording apparatus according to any one of claims 1 to 4, The processing liquid discharge unit includes a first processing liquid discharge head and a second processing liquid discharge head, respectively provided on both sides adjacent to the width direction of the ink discharge unit.

[0012] The invention according to claim 6 is an inkjet recording apparatus according to claim 5, During the scanning of the image forming unit, a control unit is provided that discharges the processing liquid from at least the processing liquid discharge head provided in front of the scanning direction of the image forming unit among the first and second processing liquid discharge heads.

[0013] The invention according to claim 7 is an inkjet recording apparatus according to claim 6, During the scanning of the image forming unit, the control unit does not drive the processing liquid discharge head and the airflow generating unit behind the scanning direction.

[0014] The invention according to claim 8 is an inkjet recording apparatus according to claim 6, During the scanning of the image forming unit, the control unit drives the first and second processing liquid discharge heads and a plurality of the airflow generating units.

[0015] The invention according to claim 9 is an inkjet recording apparatus according to claim 8, The control unit makes the amounts of airflow generated by the plurality of airflow generating units different.

[0016] The invention according to claim 10 is an inkjet recording apparatus according to any one of claims 1 to 4, A control unit is provided that varies the amount of airflow generated by the airflow generation unit according to the scanning direction of the image forming unit.

[0017] The invention according to claim 11 is an inkjet recording apparatus according to any one of claims 1 to 4, A control unit is provided that varies the amount of airflow generated by the airflow generation unit according to the coverage of the image formed by the image forming unit.

[0018] The invention according to claim 12 is an inkjet recording apparatus according to any one of claims 1 to 4, A control unit is provided that varies the amount of airflow generated by the airflow generation unit according to the image forming speed of the image forming unit.

Advantages of the Invention

[0019] According to the present invention, it is possible to suppress ejection failures and image disturbances caused by the aggregation of the processing liquid and the ink at the head.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0021] Hereinafter, the droplet ejection device according to the embodiment of the present invention will be described in detail with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples. In the following description, those having the same function and configuration are denoted by the same reference numerals, and the description thereof will be omitted.

[0022] [First Embodiment] [Overall Configuration of Droplet Ejection Device] FIG. 1 is a perspective view of an inkjet recording apparatus 1 which is an embodiment of the droplet ejection device of the present invention. FIG. 2 is a block diagram showing the functional configuration of the inkjet recording apparatus 1. The inkjet recording apparatus 1 includes a control unit 2, a conveyance unit 3, and an image forming unit 4.

[0023] Hereinafter, in the X direction, Y direction, and Z direction are the directions shown in FIG. 1. Further, hereinafter, the X direction, Y direction, and Z direction will be described as the width direction, conveyance direction, and height direction, respectively.

[0024] (Control Unit) The control unit 2 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), and a ROM (Read Only Memory). The control unit 2 controls the overall operation of the inkjet recording apparatus 1.

[0025] The CPU controls each part of the inkjet recording apparatus 1. The RAM is a volatile memory that can temporarily store various information by writing and reading. The ROM is a non-volatile memory in which various information and programs are stored so that they can be read. More specifically, the control unit 2 reads out a program designated from various programs stored in the ROM by the CPU and expands it in the RAM. Then, the control unit 2 executes various processes in cooperation with the expanded program.

[0026] (Conveyance Unit) As shown in FIG. 1, the conveying unit 3 includes two conveying rollers 3a and 3b that rotate in the conveying direction about a rotating shaft extending in the width direction. The conveying unit 3 also includes an annular conveying belt 3c.

[0027] The inner side of the conveying belt 3c is supported by the conveying rollers 3a and 3b. Also, the recording medium M is placed on the conveying surface of the conveying belt 3c. Then, the conveying rollers 3a and 3b rotate in the conveying direction and move in a circular motion in response to the operation of the conveying motor of the rollers. As a result, the conveying belt 3c conveys the recording medium M in the conveying direction.

[0028] Moreover, it is preferable that a predetermined adhesive is applied to the placement surface, which is a surface different from the inner surface of the conveying belt 3c that contacts the conveying rollers 3a and 3b and is the outer surface on the side where the recording medium M is placed. With this configuration, even when the airflow generating unit 44 described later generates an airflow, it is possible to suppress the occurrence of misalignment in the recording medium M.

[0029] The recording medium M is, for example, a piece of cloth cut to a certain size. The recording medium M is supplied onto the conveying belt 3c by a medium supply unit (not shown). The recording medium M on which an image has been recorded by the ink ejection of the image forming unit 4 is discharged to a predetermined discharge unit. Note that the recording medium M is not limited to cloth. The recording medium M may be various media such as paper as long as it can fix the landed ink.

[0030] (Image Forming Unit) The image forming unit 4 forms an image by ejecting color ink onto the recording medium M conveyed by the conveying unit 3 at an appropriate timing based on image data acquired from an external device or the like. The image forming unit 4 includes a carriage 41 equipped with an ink ejection unit 42 having a plurality of inkjet heads 421 that eject inks of respective colors of C (cyan), M (magenta), Y (yellow), and K (black).

[0031] {Carriage} Figure 3A is a schematic front view of the cross-section of carriage 41 as seen from the conveyance direction. An ink ejection unit 42, a processing liquid ejection unit 43, and an air flow generation unit 44 are mounted on carriage 41. Carriage 41 has, for example, a belt stretched between two pulleys that rotate by a motor (not shown). Carriage 41 scans ink ejection unit 42, processing liquid ejection unit 43, and air flow generation unit 44 in the width direction by the rotational movement of the motor based on the drive signal output by control unit 2.

[0032] Also, the inkjet recording apparatus 1 according to the present embodiment is of a serial head type that forms an image by ejecting color ink from ink ejection unit 42 onto recording medium M while scanning carriage 41 in the width direction. Note that an image may be formed by scanning carriage 41 once, or an image may be formed by scanning carriage 41 a plurality of times.

[0033] Also, the inkjet recording apparatus 1 according to the present embodiment is of an in-line type. That is, image forming unit 4 continuously forms an image by ejecting ink from ink ejection unit 42 following the preprocessing by the ejection of the processing liquid from processing liquid ejection unit 43.

[0034] {Ink ejection unit} Ink ejection unit 42 includes a plurality of inkjet heads 421 that eject color ink. Each inkjet head 421 includes a tank for color ink, a flow path, a piezoelectric element, a plurality of nozzles, and the like. As shown in Figure 3A, a plurality of inkjet heads 421 are mounted in the width direction on carriage 41. Inkjet head 421 ejects color ink onto recording medium M by applying pressure fluctuations to the color ink supplied from the tank to the nozzles through the flow path under the control of control unit 2.

[0035] Note that the color ink ejected by ink ejection unit 42 is, for example, pigment ink. Pigment ink is ink containing pigment, resin particles (binder resin), and water. An image formed with pigment ink exhibits high color development because pigment particles are likely to be exposed near the image forming surface of recording medium M.

[0036] {Processing liquid discharge unit} The processing liquid discharge unit 43 includes a processing liquid discharge head 431 provided at one end in the width direction of the carriage 41. The processing liquid discharge head 431 is provided outside the ink discharge unit 42 and includes a tank, a flow path, a piezoelectric element, a plurality of nozzles, etc. for the processing liquid, and discharges the processing liquid under the control of the control unit 2, similar to the inkjet head 421.

[0037] Specifically, the processing liquid discharged from the processing liquid discharge head 431 is, for example, a pretreatment ink containing a flocculant, and is mixed in a liquid state with the color ink discharged from the inkjet head 421. The pretreatment ink contains at least a flocculant and may contain other components such as a solvent, a surfactant, or water. The flocculant contained in the pretreatment ink is not particularly limited as long as it can cause aggregates when contacting the color ink, and is, for example, a polyvalent metal salt, an organic acid, or an inorganic acid.

[0038] Also, the processing liquid discharge head 431 discharges the processing liquid when the carriage 41 scans from the other end provided with the ink discharge unit 42 to the one end provided with the processing liquid discharge unit 43. According to this configuration, image formation can be performed simultaneously with pretreatment in one scan of the carriage 41, improving productivity.

[0039] {Airflow generation unit} The airflow generation unit 44 is provided between the ink discharge unit 42 and the processing liquid discharge unit 43 in the width direction of the carriage 41. The airflow generation unit 44 is configured to generate an airflow on the lower surface side of the carriage 41 and includes an air intake device 441 in this embodiment. The configuration of the air intake device 441 is not particularly limited, and for example, it includes a suction port and a suction pump that forms a negative pressure at the suction port.

[0040] Also, as shown in FIG. 3A, at least a part of the carriage 41 on the side of the processing liquid discharge unit 43 is formed such that the gap with the recording medium M (that is, the distance between the top plate of the carriage 41 and the recording medium M) is wider than that on the side of the ink discharge unit 42. Specifically, for example, the gap between the end on the side of the processing liquid discharge unit 43 and the recording medium M is about 10 mm, and the gap between the end on the side of the ink discharge unit 42 and the recording medium M is about 1 to 5 mm.

[0041] With this configuration, in the image forming unit 4, gas flows more easily into the side of the processing liquid discharge unit 43 than into the side of the ink discharge unit 42. As a result, in the inkjet recording apparatus 1 according to the present embodiment, the gas flow rate in the image forming unit 4 is higher on the side of the processing liquid discharge unit 43 than on the side of the ink discharge unit 42. Thus, the gap between a part on the side of the processing liquid discharge unit 43 of the carriage 41 and the recording medium M functions as an air flow adjusting unit that adjusts the air flow so that the air flow on the side of the processing liquid discharge unit 43 increases.

[0042] By providing such an air flow adjusting unit, when the intake device 441 sucks, as shown in FIG. 3B, an air flow is generated from the side of the processing liquid discharge unit 43 toward the intake device 441. Then, the air flow can suppress the adhesion of the color ink mist to the nozzle surface of the head of the processing liquid discharge unit 43.

[0043] Note that the control unit 2 preferably controls the air flow generation unit 44 to generate an air flow only at the timing of scanning over the image forming area of the recording medium M and not to generate an air flow at other timings. With this configuration, the amount of energy consumed by the air flow generation unit 44 can be saved. Note that such on / off control of the air flow generation unit 44 may be performed by the control unit 2 or by the air flow generation unit 44 itself.

[0044] [Effects of the First Embodiment] As described above, the inkjet recording apparatus 1 according to the present embodiment includes an air flow adjusting unit, and the flow rate of the gas passing through is different between the ink ejection unit 42 side and the processing liquid ejection unit 43 side with the boundary between the ink ejection unit 42 and the processing liquid ejection unit 43. Specifically, the gap between a part of the processing liquid ejection unit 43 and the recording medium M is larger than the gap between the ink ejection unit 42 and the recording medium M. According to this configuration, when the intake device 441 intakes air, the air on the side of the processing liquid ejection unit 43 where the flow rate of the gas passing through is larger than that on the ink ejection unit 42 side is sucked by the intake device 441. Then, due to the air flow generated in this way, the adhesion of the ink mist ejected from the ink ejection unit 42 to the processing liquid ejection unit 43 and the adhesion of the processing liquid mist ejected from the processing liquid ejection unit 43 to the ink ejection unit 42 are suppressed. Further, since the air flow is sucked by the intake device 441, the occurrence of image disturbance due to the generation of an air flow on the ink ejection unit 42 side is also suppressed.

[0045] Further, the processing liquid ejection head 431 is provided outside the ink ejection unit 42. According to this configuration, the above effects can be obtained for all of the plurality of inkjet heads 421.

[0046] [Second Embodiment] The inkjet recording apparatus 1 according to the second embodiment will be described with reference to FIGS. 4A and 4B. Note that the same reference numerals are given to the configurations substantially the same as those in the first embodiment, and the detailed description thereof is omitted. The inkjet recording apparatus 1 according to the second embodiment is different from the first embodiment in that the air flow generation unit 44 is an air supply device 442 as shown in FIG. 4B.

[0047] {Air supply device} The air supply device 442 is not particularly limited as long as it can generate an air flow by blowing air to the recording medium M. For example, it includes an ejection port and a fan, a compressor, etc. that inject pressurized air from the ejection port.

[0048] The air supply device 442 preferably generates an air current at an angle of 45° to 135° with respect to the vertical direction of the recording medium M. When an air current at an angle less than 45° or greater than 135° with respect to the vertical direction of the recording medium M is generated, if the recording medium M has lint, the ink adhering to the lint may be blown onto other areas, and the formed image may be disturbed. On the other hand, when the air supply device 442 generates an air current at an angle of 45° to 135°, particularly preferably 90°, with respect to the vertical direction of the recording medium M, image disturbance can be suppressed.

[0049] [Effect of the Second Embodiment] As described above, the inkjet recording apparatus 1 according to the second embodiment includes the air supply device 442 as the air current generation unit 44. According to this configuration, the gas blown by the air supply device 442 heads toward the side of the processing liquid discharge unit 43 with a large gap from the recording medium M, as shown in FIG. 4B. Then, the air current thus generated suppresses the adhesion of the ink mist discharged from the ink discharge unit 42 to the processing liquid discharge unit 43 and the adhesion of the processing liquid mist discharged from the processing liquid discharge unit 43 to the ink discharge unit 42. Further, since the air current generated by the air current generation unit 44 flows toward the processing liquid discharge unit 43 side, the generation of image disturbance due to the generation of an air current on the ink discharge unit 42 side is also suppressed.

[0050] [Third Embodiment] The inkjet recording apparatus 1 according to the third embodiment will be described with reference to FIG. 5. Note that the same reference numerals are given to the configurations substantially the same as those in the first and second embodiments, and the detailed description thereof is omitted. As shown in FIG. 5, the inkjet recording apparatus 1 according to the third embodiment is different from the first and second embodiments in that the image forming unit 4 includes both the air intake device 441 and the air supply device 442 as the air current adjustment unit. Specifically, as shown in FIG. 5, in the image forming unit 4 according to the present embodiment, the air supply device 442 is provided on one side in the width direction of the processing liquid discharge unit 43, and the air intake device 441 is provided on the other side.

[0051] [Effect of the Third Embodiment] In this configuration, as shown in FIG. 5, the gas blown by the air supply device 442 is sucked by the air intake device 441. Since the air intake device 441 and the air supply device 442, which are airflow adjustment units, are provided on both sides in the width direction with the processing liquid discharge unit 43 interposed therebetween, the gas flow rate on the side of the processing liquid discharge unit 43 is higher than that on the side of the ink discharge unit 42. Therefore, similar to the first and second embodiments, the ink mist discharged from the ink discharge unit 42 is prevented from adhering to the processing liquid discharge unit 43, and the processing liquid mist discharged from the processing liquid discharge unit 43 is prevented from adhering to the ink discharge unit 42 by the airflow generated by the airflow generation unit 44. Further, since the gas blown by the air supply device 442 is sucked by the air intake device 441, image distortion caused by the generation of an airflow on the side of the ink discharge unit 42 is also suppressed.

[0052] In FIG. 5, a configuration is illustrated in which the air supply device 442 is provided on the side of the ink discharge unit 42 and the air intake device 441 is provided on the other side with respect to the processing liquid discharge unit 43, but the reverse may also be possible. That is, even if the air intake device 441 is provided on the side of the ink discharge unit 42 and the air supply device 442 is provided on the other side, the same effects as the configuration of FIG. 5 can be obtained.

[0053] Also, in FIG. 5, even if only the air intake device 441 and the air supply device 442 are provided, the gas flow rate on the side of the processing liquid discharge unit 43 increases. Therefore, a case is illustrated in which the gap between the recording medium M on the side of the ink discharge unit 42 and the side of the processing liquid discharge unit 43 is made substantially equal, but the present invention is not limited to this. That is, similar to the first and second embodiments, the gap between a part of the processing liquid discharge unit 43 and the recording medium M may be made larger than the gap between the ink discharge unit 42 and the recording medium M.

[0054] [Fourth Embodiment] The inkjet recording apparatus 1 according to the fourth embodiment will be described with reference to FIG. 6. Note that the same reference numerals are given to substantially the same configurations as those in the first to third embodiments, and detailed descriptions thereof are omitted. As shown in FIG. 6, the inkjet recording apparatus 1 according to the fourth embodiment is different from the first to third embodiments in that the image forming unit 4 includes a processing liquid discharge unit 43 and an airflow generation unit 44, which is an airflow adjustment unit, on both sides in the width direction with the ink discharge unit 42 interposed therebetween.

[0055] In this configuration, image formation can be performed not only when the carriage 41 scans from one side to the other side, but also when it scans from the other side to one side. Specifically, when the carriage 41 scans from one side to the other side, the control unit 2 causes the processing liquid discharge unit 43 on the other side (i.e., the front in the scanning direction) to discharge the processing liquid. Then, the control unit 2 causes the ink discharge unit 42 following it to discharge ink. Also, when the carriage 41 scans from the other side to one side, the control unit 2 causes the processing liquid discharge unit 43 on one side to discharge the processing liquid. Then, the control unit 2 causes the ink discharge unit 42 following it to discharge ink.

[0056] [Effects of the Fourth Embodiment] With this configuration, since the color ink can be discharged from the color ink discharge unit 42 after the processing liquid is discharged from the processing liquid discharge unit 43 in the front in the scanning direction both in the forward and backward paths of the carriage 41, the productivity of image formation can be further enhanced.

[0057] In this configuration, the control unit 2 only needs to operate at least the airflow generation unit 44 in the front in the scanning direction, but the airflow generation unit 44 in the rear in the scanning direction may or may not be operated.

[0058] As described above, during image formation, the control unit 2 causes the processing liquid discharge unit 43 in the front in the scanning direction to discharge the processing liquid. At this time, although the possibility is low, the mist of the color ink discharged by the inkjet head 421 may adhere to the processing liquid discharge unit 43 in the rear in the scanning direction. Therefore, if the configuration is such that the airflow generation unit 44 in the rear in the scanning direction is also operated, the possibility of the processing liquid and the ink aggregating at the head can be further reduced. On the other hand, not operating the airflow generation unit 44 in the rear in the scanning direction is more excellent in energy efficiency.

[0059] Regarding whether to operate the airflow generation unit 44 in the rear in the scanning direction in the inkjet recording apparatus 1 according to the fourth embodiment, as described above, both have different advantages. Therefore, it is preferably selectable by the user as appropriate.

[0060] Also, when operating the airflow generation unit 44 behind the scanning direction, the control unit 2 may control such that the airflow generation unit 44 behind the scanning direction generates a smaller amount of airflow than the airflow generation unit 44 in front of the scanning direction.

[0061] [Modification Example] As described above, specific explanations have been made based on the embodiments according to the present invention. However, the present invention is not limited to the above-described embodiments. Of course, various modifications are possible, including those within the scope of the invention described in the claims and the equivalent scope thereof.

[0062] For example, the control unit 2 may vary the amount of airflow generated by the airflow generation unit 44 according to the printing coverage in the acquired image data. Specifically, when the printing coverage is high, the ejection amounts of the processing liquid and color ink also increase, making it easier for mist to occur. Therefore, it is preferable to relatively increase the amount of airflow generated by the airflow generation unit 44.

[0063] Also, the control unit 2 may vary the amount of airflow generated by the airflow generation unit 44 according to the printing speed. Specifically, when the printing speed is high, mist is likely to adhere to the head surface. Therefore, it is preferable to relatively increase the amount of airflow generated by the airflow generation unit 44.

[0064] Also, in the above, the image forming unit 4 in which each component is mounted on a single carriage 41 is exemplified, but the present invention is not limited thereto. Specifically, the present invention can be appropriately applied even to an inkjet recording apparatus 1 including separately independent image forming units 4 for each component.

Explanation of Reference Numerals

[0065] 1 Inkjet recording apparatus 2 Control unit 3 Conveying unit 4 Image forming unit 41 Carriage (airflow adjustment unit) 42 Ink ejection unit 421 Inkjet head 43 Processing liquid discharge unit 431 Processing liquid discharge head 44 Airflow generation unit 441 Intake device (airflow adjustment unit) 442 Air supply device (airflow adjustment unit) M Recording medium

Claims

1. A transport unit that transports a recording medium in a transport direction, An inkjet recording apparatus comprising: an image forming unit that forms an image on a recording medium by discharging ink along with scanning in a width direction orthogonal to the transport direction, The image forming unit includes an ink discharge unit including an inkjet head that discharges ink, A treatment liquid discharge unit including a treatment liquid discharge head that discharges a treatment liquid for aggregating the ink, An airflow generation unit provided at least between the ink discharge unit and the treatment liquid discharge unit, and generating an airflow in a height direction orthogonal to the transport direction and the width direction, An inkjet recording apparatus comprising: an airflow adjustment unit that adjusts so that the flow rate of the gas passing through the treatment liquid discharge unit side is larger than that of the ink discharge unit side with the boundary between the ink discharge unit and the treatment liquid discharge unit.

2. The inkjet recording apparatus according to claim 1, wherein the treatment liquid discharge head is provided outside the ink discharge unit.

3. The inkjet recording apparatus according to claim 1, wherein the airflow adjustment unit includes a portion where a gap between at least a part of the treatment liquid discharge unit and the recording medium is larger than a gap between the ink discharge unit and the recording medium.

4. The airflow generation unit includes an intake device that sucks gas from the recording medium side and a blower device that blows gas to the recording medium side, The inkjet recording apparatus according to claim 1, wherein the airflow adjustment unit includes the intake device and the blower device, and is provided on both sides in the width direction of the treatment liquid discharge unit.

5. The inkjet recording apparatus according to any one of claims 1 to 4, wherein the treatment liquid discharge unit includes a first treatment liquid discharge head and a second treatment liquid discharge head on both sides in the width direction of the ink discharge unit.

6. The inkjet recording apparatus according to claim 5, further comprising a control unit that discharges a treatment liquid from at least the treatment liquid discharge head provided in front of the scanning direction of the image forming unit among the first and second treatment liquid discharge heads during scanning of the image forming unit.

7. The inkjet recording apparatus according to claim 6, wherein the control unit does not drive the treatment liquid discharge head and the airflow generation unit behind the scanning direction during scanning of the image forming unit.

8. The inkjet recording apparatus according to claim 6, wherein the control unit drives the first and second processing liquid ejection heads and the plurality of airflow generation units during scanning of the image forming unit.

9. The inkjet recording apparatus according to claim 8, wherein the control unit varies the amount of airflow generated by the plurality of airflow generation units.

10. The inkjet recording apparatus according to any one of claims 1 to 4, comprising a control unit that varies the amount of airflow generated by the airflow generation unit according to the scanning direction of the image forming unit.

11. The inkjet recording apparatus according to any one of claims 1 to 4, comprising a control unit that varies the amount of airflow generated by the airflow generation unit according to the coverage of the image formed by the image forming unit.

12. The inkjet recording apparatus according to any one of claims 1 to 4, comprising a control unit that varies the amount of airflow generated by the airflow generation unit according to the image forming speed of the image forming unit.

Images