JP2021084310A - Liquid discharge device - Google Patents

Abstract

To prevent a liquid application position on a recording medium from shifting, while securing adhesion between a contact member and the recording medium.SOLUTION: A liquid discharge device according to one embodiment of the present invention comprises: a liquid application part that applies liquid to a recording medium; a contact member that contacts a surface different from a liquid application surface of the recording medium; a destaticizing part that destaticizes the surface different from the liquid application surface of the recording medium after the liquid application part applies liquid to the recording medium; a charging part that applies electrical charge to the surface different from the liquid application surface after the destaticizing part destaticizes the surface; and a voltage application part that applies a voltage to the contact member.SELECTED DRAWING: Figure 1

Description

The present invention relates to a liquid discharge device.

Conventionally, in a liquid discharge device, a liquid discharge head is used to apply a liquid to a recording medium to form an image, and the recording medium after image formation is brought into contact with a contact member such as a temperature control drum (for example,). See Patent Document 1).

Further, a technique is disclosed in which a static eliminator is provided on the downstream side of the liquid discharge head to remove static electricity from the recording medium held by contacting a contact member such as a holding drum, and then the recording medium is peeled off from the holding drum (for example). See Patent Document 2).

However, in the technique of Patent Document 1, when the transport speed of the recording medium is increased, the adhesion between the recording medium and the contact member is lowered due to the presence of air drawn in when the recording medium is brought into contact with the contact member. Wrinkles may occur on the recording medium.

Further, in the technique of Patent Document 2, since the static eliminator is arranged on the liquid applying surface of the recording medium, the liquid applying position on the recording medium may shift, and the image quality formed on the recording medium may deteriorate.

An object of the present invention is to prevent the liquid application position from shifting on the recording medium while improving the adhesion between the contact member and the recording medium.

In the liquid discharge device according to one aspect of the present invention, a liquid applying portion that applies a liquid to a recording medium, a contact member that contacts a surface different from the liquid applying surface of the recording medium, and the liquid applying unit are the recording medium. A static elimination unit that removes static electricity from a surface of the recording medium that is different from the liquid application surface after the liquid is applied to the recording medium, and a charging unit that applies electric charge to a surface different from the liquid application surface after the static elimination unit is charged. A voltage application unit for applying a voltage to the contact member is provided.

According to the present invention, it is possible to improve the adhesion between the contact member and the recording medium, prevent the liquid application position from shifting on the recording medium, and improve the image quality.

It is a figure which shows the structural example of the image forming apparatus which concerns on 1st Embodiment. It is a figure which shows the structural example of the hot water temperature maintenance mechanism. It is a figure which shows the structural example of the image forming apparatus which concerns on 2nd Embodiment. It is a figure which shows the structural example of the image forming apparatus which concerns on 3rd Embodiment. It is a figure which shows the structural example of the image forming apparatus which concerns on 4th Embodiment.

Hereinafter, modes for carrying out the invention will be described with reference to the drawings. In each drawing, the same components may be designated by the same reference numerals and duplicate description may be omitted.

In the embodiment, after the liquid is applied to the recording medium by the liquid application unit, the contact member is brought into contact with a surface different from the liquid application surface of the recording medium. This contact member is, for example, a temperature control drum for drying the liquid on the recording medium by adjusting the temperature of the recording medium by contact with the recording medium.

Further, in the embodiment, after the liquid applying portion applies the liquid to the recording medium, the surface different from the liquid applying surface of the recording medium is statically removed, and after the static elimination, the surface different from the liquid applying surface of the recording medium is charged. It is charged and a voltage is applied to the contact surface of the contact member with the recording medium.

As a result, the contact member and the recording medium are electrostatically adsorbed to improve the adhesion between the two, and the surface different from the liquid application surface of the recording medium is charged and statically removed to position the liquid application position on the recording medium. Prevent slippage.

It should be noted that, in the terms of the embodiments described below, image formation, recording, printing, printing, and printing are all synonymous.

Further, in the embodiment, the "device for discharging a liquid" is a device provided with a liquid discharge head or a liquid discharge unit and driving the liquid discharge head to discharge the liquid. The "device for discharging liquid" and the "device for discharging liquid" are synonymous.

The "device for discharging the liquid" may include means for feeding, transporting, and discharging paper to which the liquid can be attached, as well as a pretreatment device, a posttreatment device, and the like.

For example, as a "device for ejecting a liquid", there is an image forming apparatus which is an apparatus for forming an image on paper by ejecting a liquid such as ink.

The above-mentioned "material to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as one that adheres and adheres, and one that adheres and permeates.

The "liquid" may have a viscosity and surface tension that can be discharged from the head, and is not particularly limited, but has a viscosity of 30 mPa · s or less at room temperature, under normal pressure, or by heating or cooling. It is preferable to have. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functionalizing materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solvents, suspensions, emulsions, etc. containing edible materials such as natural pigments, etc., for example, inks for inkjets, surface treatment liquids, constituents of electronic elements and light emitting elements, and formation of electronic circuit resist patterns. It can be used for applications such as liquids for three-dimensional modeling.

Further, the "device for discharging the liquid" includes, but is not limited to, a device in which the liquid discharge head and the device to which the liquid can adhere move relatively. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.

The "liquid discharge unit" is a liquid discharge head integrated with functional parts and a mechanism, and is an aggregate of parts related to liquid discharge. For example, the "liquid discharge unit" includes a combination of at least one of a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, and a main scanning movement mechanism with a liquid discharge head.

Here, "integration" means, for example, a liquid discharge head and a functional component, a mechanism in which the mechanism is fixed to each other by fastening, adhesion, engagement, etc., or one in which one is movably held with respect to the other. Including. Further, the liquid discharge head, the functional parts, and the mechanism may be detachably attached to each other.

For example, as a liquid discharge unit, there is one in which a liquid discharge head and a head tank are integrated. In addition, there are some that are connected to each other by a tube or the like to integrate the liquid discharge head and the head tank. Here, a unit including a filter can be added between the head tank of these liquid discharge units and the liquid discharge head.

Further, as a liquid discharge unit, there is a liquid discharge head and a carriage integrated.

Further, as a liquid discharge unit, there is a liquid discharge head in which the liquid discharge head and the scanning movement mechanism are integrated by holding the liquid discharge head movably by a guide member forming a part of the scanning movement mechanism. In some cases, the liquid discharge head, the carriage, and the main scanning movement mechanism are integrated.

Further, as a liquid discharge unit, there is a carriage to which a liquid discharge head is attached, in which a cap member which is a part of the maintenance / recovery mechanism is fixed, and the liquid discharge head, the carriage, and the maintenance / recovery mechanism are integrated. ..

Further, as a liquid discharge unit, there is a liquid discharge unit in which a tube is connected to a head tank or a liquid discharge head to which a flow path component is attached, and the liquid discharge head and a supply mechanism are integrated. Through this tube, the liquid of the liquid storage source is supplied to the liquid discharge head.

The main scanning movement mechanism shall also include a single guide member. Further, the supply mechanism includes a single tube and a single loading unit.

The "liquid discharge head" is a functional component that discharges and ejects liquid from a nozzle.

Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electrothermal conversion elements such as heat-generating resistors, and electrostatic actuators that consist of a vibrating plate and counter electrodes are used as energy sources for discharging liquid. Includes what to do.

In the embodiment, a case where “a liquid can be attached” is used as a film, “liquid” is used as ink, and the “liquid ejection device” is used as an inkjet image forming apparatus will be described as an example. The film is a thin film used for food packaging and the like and made of a plastic such as polyethylene terephthalate. The film is an example of a "recording medium".

[First Embodiment]
<Structure example of image forming apparatus 100>
First, the configuration of the image forming apparatus 100 according to the first embodiment will be described with reference to FIG. FIG. 1 is a diagram showing an example of the configuration of the image forming apparatus 100.

As shown in FIG. 1, the image forming apparatus 100 includes an ink ejection unit 1, a first transfer roller 301, a drying unit 10, and a second transfer roller 302.

The film 2 is supplied from the supply unit, and is conveyed by the transfer unit along the transfer direction 21 while tension is applied in the tension direction 20 by the supply unit in order to ensure the transfer accuracy.

The image forming apparatus 100 ejects ink from the ink ejection unit 1 to the film 2 and applies ink to the surface 2a of the film 2 to form an image. The ink 5 in FIG. 1 indicates the ink applied to the surface 2a of the film 2. Here, the front surface 2a of the film 2 corresponds to the "liquid application surface", and the back surface 2b, which is the surface of the film 2 opposite to the surface 2a, corresponds to the "surface different from the liquid application surface".

The first transport roller 301 is a rotating member that contacts the back surface 2b of the film 2 to support the film 2, and feeds the film 2 toward the drying unit 10. The second transport roller 302 is a rotating member that comes into contact with the surface 2a of the film 2 to support the film 2, and sends out the film 2 that has passed through the drying unit 10. Here, the first transport roller 301 is an example of a transport member.

The supply unit is not shown in FIG. Further, the transfer unit is not shown in FIG. 1 except for a part of the first transfer roller 301, the second transfer roller 302, and the like.

The film 2 is a roll-shaped continuous film that can be wound up. For example, it is a film used for flexible packaging such as food packaging made of stretched polypropylene (OPP; Oriented Poly-Propylene).

The ink ejected from the ink ejection unit 1 is, for example, water-based ink. The water-based ink is an ink containing a solvent and a colorant as main components and mainly using water as a solvent.

The ink ejection unit 1 as an example of the liquid applying portion includes an ink ejection head 1W for white, an ink ejection head 1K for black, an ink ejection head 1C for cyan, an ink ejection head 1M for magenta, and yellow. Ink ejection head 1Y for use is provided.

The ink ejection head 1W ejects white (W) ink, and the ink ejection head 1K ejects black (K) ink to apply ink to the surface of the film 2, respectively. Further, the ink ejection head 1C ejects cyan (C) ink, the ink ejection head 1M ejects magenta (M) ink, and the ink ejection head 1Y ejects yellow (Y) ink, so that the film 2 Ink is applied to each surface of.

However, in the embodiment, the image forming apparatus 100 including the ink ejection heads of five colors of white (W), black (K), cyan (C), magenta (M), and yellow (Y) will be described. It is not limited. The image forming apparatus 100 may further include an ink ejection head corresponding to green (G), red (R), light cyan (LC) and / or other colors. Further, only the black ink ejection head 1K may be provided.

Further, in the embodiment, the order in which the ink ejection heads in the ink ejection unit 1 are arranged is yellow (Y), magenta (M), cyan (C), black (K), and white from the upstream side in the transport direction 21 of the film 2. An example of (W) is shown, but the present invention is not limited to this. The order in which the ink ejection heads in the ink ejection unit 1 are arranged can be changed as appropriate.

The drying unit 10 includes a temperature control drum 3 and a warm air generating unit 4, and adjusts the temperature of the film 2 to dry the ink 5 applied to the surface 2a of the film 2.

The temperature control drum 3 as an example of the contact member is a cylindrical rotating drum that can rotate around the cylindrical axis (direction of arrow 3b in FIG. 1), and the contact surface (outer peripheral surface) 3a contacts the back surface 2b of the film 2. The film 2 is conveyed along the conveying direction 21 by rotating while rotating. Note that FIG. 1 shows a view of the temperature control drum 3 as viewed from the direction of the cylindrical axis.

The inside of the temperature control drum 3 is filled with hot water kept at a predetermined temperature. The temperature control drum 3 maintains the temperature of the film 2 at a predetermined temperature by transferring the heat of the hot water from the back surface 2b to the film 2. This predetermined temperature is, for example, 70 degrees.

The warm air generating unit 4 as an example of the heating unit blows the warm air generated by heating with a heater or the like to the surface 2a of the film 2 to heat the film 2 and raise the ink temperature to promote drying. ..

Here, in the embodiment, the temperature control drum 3 transfers heat to the back surface 2b of the film 2, and the warm air generating portion 4 heats the front surface 2a of the film 2, but the overall temperature in the thickness direction of the film 2 is the heat capacity. Is dominated by the temperature of the large temperature control drum 3.

As an example of the experimental result, when the temperature of the hot water inside the temperature control drum 3 is 70 degrees and the temperature of the hot air of the hot air generating unit 4 is 300 degrees, the temperature of the back surface of the film 2 is 85 degrees and the film. The temperature of the ink on the surface 2a of No. 2 was 150 degrees.

For this reason, the warm air generating unit 4 sets the ink on the surface 2a of the film 2 to 100 degrees or more, which is the boiling point of the water-based ink, and the temperature control drum 3 sets the temperature of the film 2 to 100, which is a general heat resistant temperature. It can be seen that it can be set below the temperature. The action of the temperature control drum 3 prevents heat damage to the film 2 and promotes drying of the ink.

Further, the image forming apparatus 100 includes a charger 202, a voltage applying device 203, and a static eliminator 204a.

The charger 202 as an example of the charging unit is provided between the temperature control drum 3 and the first transport roller 301 in the vicinity of the contact start region 10a circled by the broken line in FIG. The contact start region 10a is an region on the upstream side of the temperature control drum 3 in the transport direction 21 of the film 2 where the film 2 and the temperature control drum 3 start to come into contact with each other. The charger 202 applies an electric charge to the back surface 2b of the film 2 to charge the back surface 2b of the film 2 to a negative potential 41 as an example of a potential having a predetermined polarity.

The voltage application device 203 as an example of the voltage application unit applies a voltage to the contact surface 3a of the film 2 in the temperature control drum 3 with the back surface 2b, so that the positive potential as an example of the potential having a polarity opposite to the predetermined polarity. 42 is charged with the contact surface 3a.

The static eliminator 204a as an example of the static eliminator is provided between the first transport roller 301 and the charger 202 on the downstream side of the ink ejection unit 1 in the transport direction 21, and is applied to the film 2 after the ink is applied to the film 2. The back surface 2b of the above is statically eliminated.

Here, in the vicinity of the contact start region 10a where the film 2 begins to wind around the temperature control drum 3, an air flow may be generated due to the transportation of the film 2. Due to this air flow, the film 2 winds around the temperature control drum 3 with air entering between the back surface 2b of the film 2 and the contact surface 3a of the temperature control drum 3, and the adhesion between the back surface 2b and the contact surface 3a is reduced. The film 2 may be wrinkled.

On the other hand, in the present embodiment, the back surface 2b of the film 2 charged to the negative potential 41 by the charger 202 and the contact surface 3a of the temperature control drum 3 charged to the positive potential 42 by the voltage applying device 203 are electrostatically charged. It attracts each other due to its adsorption action. As a result, it is difficult for air to enter between the back surface 2b and the contact surface 3a.

Further, the static eliminator 204a sets the potential of the back surface 2b of the film 2 charged by the charger 202 to approximately 0 V by static elimination, so that the film 2 is almost uncharged. As a result, the back surface 2b of the film 2 is surely charged to a desired potential when the back surface 2b is charged by the charger 202.

Further, before the film 2 is wound around the temperature control drum 3, the ink 5 has not yet been fixed (fixed) to the film 2. Therefore, when the charger 202 and the static eliminator 204a are arranged on the surface 2a side of the film 2 which is the ink applying surface, the charging device 202 and the static eliminator 204a are applied on the surface 2a due to the air flow caused by these arrangements, the charging and static eliminating actions, and the like. The ink 5 may move slightly, and the application position of the ink 5 may shift.

On the other hand, in the present embodiment, by arranging the charger 202 and the static eliminator 204a on the back surface 2b side opposite to the ink application surface in the film 2, the airflow, charging and static eliminating actions caused by these arrangements. However, the structure does not affect the ink 5 applied on the surface 2a.

Next, FIG. 2 is a diagram showing an example of the configuration of the hot water temperature maintaining mechanism 30 for maintaining the hot water 34 inside the temperature control drum 3 at a predetermined temperature. As shown in FIG. 2, the hot water temperature maintaining mechanism 30 as an example of the circulation unit includes a chiller 31 as an example of the circulation temperature adjusting unit, and an inlet side hose 32 and an outlet side hose 33 as an example of the circulation path member. Be prepared. With this configuration, the hot water temperature maintaining mechanism 30 circulates the hot water 34 filled inside the temperature control drum 3 to maintain the temperature of the hot water 34 constant. Here, the hot water 34 is an example of a circulation medium.

More specifically, the chiller 31 sends the hot water 34 controlled to a predetermined temperature by heat exchange into the temperature control drum 3 via the inlet side hose 32. Further, the chiller 31 draws in the hot water 34 inside the temperature control drum 3 via the outlet side hose 33, and controls the drawn hot water 34 to a predetermined temperature by heat exchange. Since a known technique can be applied to such a temperature control technique using the chiller 31, further detailed description will be omitted here.

<Action and effect of image forming apparatus 100>
As described above, in the present embodiment, after the ink ejection unit 1 applies ink to the film 2, the temperature control drum 3 is brought into contact with the back surface 2b of the film 2. Further, after the ink ejection unit 1 applies ink to the film 2, the back surface 2b of the film 2 is statically charged by the static eliminator 204a, and the back surface 2b of the film 2 is charged to a negative potential 41 by further applying an electric charge by the charger 202. Then, a voltage is applied to the contact surface 3a of the temperature control drum 3 by the voltage application device 203 to charge the contact surface 3a to the positive potential 42.

The back surface 2b of the film 2 charged with the negative potential 41 and the contact surface 3a of the temperature control drum 3 charged with the positive potential 42 are attracted to each other by the electrostatic adsorption action, so that between the back surface 2b and the contact surface 3a. It becomes difficult for air to enter. As a result, the adhesion between the back surface 2b of the film 2 and the contact surface 3a of the temperature control drum 3 can be improved, and wrinkles of the film 2 can be prevented.

Further, by arranging the charger 202 and the static eliminator 204a on the back surface 2b side opposite to the ink applying surface of the film 2, the airflow, charging and static eliminating actions caused by these arrangements are imparted on the surface 2a. Do not affect the ink 5. Thereby, the misalignment of the ink 5 applied on the surface 2a of the film 2 can be prevented.

In this way, it is possible to prevent the ink 5 from being displaced on the film 2 while improving the adhesion between the temperature control drum 3 and the film 2, and improve the quality of the image formed by the image forming apparatus 100. be able to.

In the present embodiment, an example is shown in which the back surface 2b of the film 2 is charged to the negative potential 41 and the contact surface 3a of the temperature control drum 3 is charged to the positive potential 42, but the present invention is not limited to this. The back surface 2b of the film 2 may be charged to the positive potential 42, and the contact surface 3a of the temperature control drum 3 may be charged to the negative potential 41. Further, if the back surface 2b of the film 2 and the contact surface 3a of the temperature control drum 3 can be attracted to each other, the charge amount of the positive potential 42 and the charge amount of the negative potential 41 do not necessarily have to be equal.

Further, in the present embodiment, the temperature control drum 3 is provided with a warm air generating unit 4 which is arranged so as to face the contact surface 3a with the film 2 and heats the ink applied to the surface 2a of the film 2. The warm air generating unit 4 blows warm air to the surface 2a of the film 2 to heat the film 2 and raise the ink temperature to promote the drying of the ink 5 on the film 2 and to apply the ink 5 to the film 2. It can be fixed faster.

The image forming apparatus 100 includes an infrared heater in place of the warm air generating unit 4 or in addition to the warm air generating unit 4, and irradiates the surface 2a of the film 2 with infrared rays to promote drying. You can also.

Further, in the present embodiment, the temperature control drum 3 adjusts the temperature of the film 2 by contacting the back surface 2b of the film 2. Since the overall temperature in the thickness direction of the film 2 is controlled by the temperature of the temperature control drum 3 having a large heat capacity, the temperature control drum 3 having a large heat capacity is brought into contact with the back surface 2b of the film 2 to generate warm air. It is possible to prevent the heat damage of the film 2 due to 4.

Further, in the present embodiment, the hot water temperature maintaining mechanism 30 for circulating the hot water 34 between the inside and the outside of the temperature control drum 3 is provided. Further, the hot water temperature maintaining mechanism 30 includes an inlet side hose 32 and an outlet side hose 33 for circulating the hot water 34, and a chiller 31 for heating or cooling the hot water 34. As a result, the hot water 34 filled inside the temperature control drum 3 is circulated to maintain the temperature of the hot water 34 substantially constant, and the temperature of the film 2 can be adjusted to a predetermined temperature by the temperature control drum 3.

Further, in the present embodiment, the first transfer roller 301 is provided on the upstream side of the temperature control drum 3 in the transfer direction 21, the charger 202 is provided between the temperature control drum 3 and the first transfer roller 301, and the first transfer is performed. A static eliminator 204a is provided between the roller 301 and the charger 202.

By providing the charger 202 between the temperature control drum 3 and the first transport roller 301, the film 2 can be charged immediately before winding around the temperature control drum 3, and the back surface 2b of the film 2 and the temperature control drum 3 can be charged. The contact surface 3a can be reliably electrostatically adsorbed.

Further, the film 2 to be conveyed tends to have a large amount of charge immediately after being separated from the first transfer roller 301. On the other hand, by providing the static eliminator 204a between the first transport roller 301 and the charger 202, the charge of the film 2 is removed by the static eliminator 204a immediately after the film 2 is separated from the first transport roller 301. , The potential can be set to near 0V.

In other words, the electric charge of the film 2 charged with a mixture of positive and negative potentials can be removed by the static eliminator 204a to make the potential of the film 2 substantially 0V. As a result, the subsequent charging by the charger 202 can be stably performed, and while stably improving the adhesion between the temperature control drum 3 and the film 2, the deviation of the ink application position on the film 2 is prevented, and the image is imaged. The quality can be improved.

[Second Embodiment]
Next, the image forming apparatus 100a according to the second embodiment will be described with reference to FIG.

FIG. 3 is a diagram showing an example of the configuration of the image forming apparatus 100a according to the second embodiment, and is a cross-sectional view of a main part of the image forming apparatus 100a. As shown in FIG. 3, the image forming apparatus 100a includes a nip roller 310.

The nip roller 310 is a rotating member that forms a nip portion with the temperature control drum 3 by coming into contact with the temperature control drum 3. Further, the nip roller 310 is provided so as to be in contact with and detached from the temperature control drum 3 by moving in the direction of the arrow 310b.

When the transfer of the film 2 is started, the nip roller 310 comes into contact with the temperature control drum 3 and forms a nip portion with the temperature control drum 3. As a result, the air entering between the film 2 and the temperature control drum 3 can be easily expelled, and the adhesion between the film 2 and the temperature control drum 3 can be further improved.

Further, when the ink applied to the surface 2a of the film 2 is in an undried state, the nip roller 310 is separated from the temperature control drum 3. This makes it possible to prevent the nip roller 310 from coming into contact with the ink applied to the surface 2a of the film 2 and distorting the image formed on the film 2.

The other effects are the same as those described in the above-described embodiment.

[Third Embodiment]
Next, the image forming apparatus 100b according to the third embodiment will be described with reference to FIG.

FIG. 4 is a diagram showing an example of the configuration of the image forming apparatus 100b according to the third embodiment, and is a cross-sectional view of a main part of the image forming apparatus 100b. As shown in FIG. 4, the image forming apparatus 100b includes static eliminators 204b and 204c.

The static eliminator 204b is provided on the downstream side of the temperature control drum 3 and the second transport roller 302, and statically eliminates the back surface 2b of the film 2 after separating the second transport roller 302.

Further, the static eliminator 204c is provided on the downstream side of the temperature control drum 3 and the second transport roller 302, and statically eliminates the surface 2a of the film 2 after separating the second transport roller 302.

Here, the film 2 may be charged by contact with the temperature control drum 3 or the second transport roller 302. When the film 2 is transported in a charged state, it may be attracted to or likely to be attracted to a charged sheet metal member or the like in the subsequent transport path, and the position and posture of the film 2 to be transported may be disturbed. If the position and orientation of the film 2 to be conveyed are disturbed, the position of the ink applied to the film 2 shifts, and the image quality formed on the film 2 deteriorates.

By eliminating static electricity on the front surface 2a and the back surface 2b of the film 2 separated from the second transport roller 302, it is possible to prevent the position and posture of the film 2 from being disturbed in the subsequent transport path, and the image quality formed on the film 2 is deteriorated. Can be prevented.

The other effects are the same as those described in the above-described embodiment.

[Fourth Embodiment]
Next, the image forming apparatus 100c according to the fourth embodiment will be described with reference to FIG.

FIG. 5 is a diagram showing an example of the configuration of the image forming apparatus 100c according to the fourth embodiment, and is a cross-sectional view of a main part of the image forming apparatus 100c. As shown in FIG. 5, the image forming apparatus 100c includes a nozzle 400.

The nozzle 400 is provided on the upstream side of the temperature control drum 3 in the transport direction 21 of the film 2 and close to the contact start region 10a where the film 2 starts to wind around the temperature control drum 3. The nozzle 400 can suck or blow air between the film 2 and the temperature control drum 3 over the entire cylindrical axis direction of the temperature control drum 3. The nozzle 400 may be installed so that a part of the nozzle 400 comes into contact with at least one of the film 2 and the temperature control drum 3.

The direction of the white arrow 401 shown in FIG. 5 indicates the direction of sucking air, and the air sucked by the nozzle 400 flows in the direction of the white arrow 401. On the other hand, when air is blown by the nozzle 400, the air flows in the direction opposite to the white arrow 401.

By blowing air between the film 2 and the temperature control drum 3 by the nozzle 400, the close contact state between the film 2 and the temperature control drum 3 or the close contact state between the film 2 and the nozzle 400 is eliminated (reset). be able to.

In other words, when the film 2 and the temperature control drum 3 are unintentionally in close contact with each other with air intervening, or when the film 2 and the nozzle 400 are in close contact with each other with air intervening. By blowing air with the nozzle 400, this close contact state can be eliminated.

After that, the back surface 2b of the film 2 is charged to the negative potential 41 by the charger 202, and then the film 2 is wound around the temperature control drum 3 charged to the positive potential 42 by the voltage applying device 203 while sucking air by the nozzle 400. .. As a result, the film 2 can be wound around the temperature control drum 3 in a state where the intervention of air is further suppressed, and the adhesion between the two can be further improved.

The other effects are the same as those described in the above-described embodiment.

Although the embodiments have been described above, the present invention is not limited to the above-described embodiments specifically disclosed, and various modifications and changes can be made without departing from the scope of claims. ..

The above-mentioned first to fourth embodiments can be combined. For example, an embodiment in which the first, second, and third embodiments are combined, and the first, third, and fourth embodiments can be applied.

100 Image forming device (example of liquid discharge device)
1 Ink ejection unit (an example of liquid application unit)
10 Drying unit 10a Contact start area 2 Film (example of recording medium)
2a surface (example of liquid application surface)
2b Back surface (an example of a surface different from the liquid application surface)
20 Tension direction 21 Transport direction 202 Charger (example of charging part)
203 Voltage application device (example of voltage application unit)
204a, 204b, 204c static eliminator (example of static eliminator)
3 Temperature control drum (an example of contact member)
30 Hot water temperature maintenance mechanism (an example of circulation part)
3a Contact surface 31 chiller (an example of circulation temperature control unit)
32 Inlet side hose (an example of circulation path member)
33 Outlet side hose (an example of circulation path member)
34 Hot water (an example of circulation medium)
301 First transport roller (an example of transport member)
302 Second transport roller 310 Nip roller 4 Warm air generating part (example of heating part)
41 Negative potential (an example of potential of predetermined polarity)
42 Positive potential (an example of potential having a polarity opposite to the predetermined polarity)
400 nozzles 5 inks (example of liquid)

Japanese Unexamined Patent Publication No. 2019-12309 Japanese Unexamined Patent Publication No. 2018-0433434

Claims (6)

A liquid applying part that applies liquid to the recording medium,
A contact member that comes into contact with a surface different from the liquid application surface of the recording medium,
A static elimination unit that removes static electricity from a surface of the recording medium that is different from the liquid-imparting surface after the liquid-imparting unit applies liquid to the recording medium.
A charging unit that applies an electric charge to a surface different from the liquid applying surface after the static elimination unit has eliminated electricity,
A liquid discharge device including a voltage application unit that applies a voltage to the contact member. By applying the electric charge, the charged portion applies a potential of a predetermined polarity to a surface different from the liquid applying surface.
The liquid discharge according to claim 1, wherein the voltage application unit applies the voltage to the contact surface of the contact member with the recording medium to impart a potential having a polarity opposite to the predetermined polarity to the contact surface. apparatus. The liquid discharge device according to claim 1 or 2, further comprising a heating unit that is arranged to face the contact surface of the contact member with the recording medium and heats the liquid applied to the liquid application surface. The liquid discharge device according to any one of claims 1 to 3, wherein the contact member contacts a surface different from the liquid application surface to adjust the temperature of the recording medium. The liquid discharge device according to claim 4, further comprising a circulation unit for circulating a circulation medium between the inside and the outside of the contact member. The circulation part
The circulation path member that circulates the circulation medium and
The liquid discharge device according to claim 5, further comprising a circulation temperature adjusting unit for heating or cooling the circulation medium.

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