Coating device, liquid ejection device, printing device

Abstract

To suppress deterioration in coating quality.SOLUTION: A coating applicator 200 includes a process liquid storage container 202 for storing process liquid 201, a scoop-up roller 205 which is stored in the process liquid storage container 202 and scoops up the process liquid 201, a coating roller 206 which transfers the process liquid 201 by the scoop-up roller 205 and coats the process liquid 201 to a sheet material P, and a defoaming blade 210 as a contact member contacting a peripheral surface of the coating roller 206, wherein the defoaming blade 210 contacts the peripheral surface of the coating roller 206 in a rotation direction of the coating roller 206, on the downstream side of a coating position a where the process liquid 201 is coated to the sheet material P by the coating roller 206, and on the upstream side of a supply position b to which the process liquid 201 is supplied from the scoop-up roller 205.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an application device, a device for discharging liquid, and a printing device. [Background technology]

[0002] For example, in some printing devices, a coating device applies a coating liquid (treatment liquid) to a sheet material to be printed, and then the sheet material is printed.

[0003] Conventionally, a known coating device is one in which, for example, a coating liquid is scooped up by a squeeze roller and supplied to a coating roller, a recording medium is pressed against the coating roller by a transfer roller, and the coating roller applies treatment liquid to the recording medium (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-196955 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a coating device, when a sheet material containing a coating liquid is pressed between a coating rotor and a pressure rotor (transfer rotor), the coating liquid may mix with air and generate bubbles. When bubbles are generated, the bubbles are transferred into the coating liquid in the supply pan that supplies the coating liquid as the coating rotor rotates, causing the liquid level in the supply pan to rise, causing the coating liquid and bubbles to overflow from the supply pan, resulting in a problem of reduced coating performance.

[0006] The present invention has been made in view of the above problems, and has an object to suppress a decrease in coating performance. [Means for solving the problem]

[0007] In order to solve the above problems, the coating apparatus according to the present invention comprises: A coating rotor that applies a coating liquid to a sheet material; a contact member that contacts a peripheral surface of the coating rotary body, The contact member is disposed on the coating rotary body downstream of a coating position where the coating liquid is applied in a rotation direction of the coating rotary body. In the tangential direction of the coating rotor Abutting The composition was as follows.

[0008] According to the present invention, the deterioration of coating performance can be suppressed. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic explanatory diagram of a printing device according to a first embodiment of the present invention. [Diagram 2] 4A and 4B are explanatory diagrams illustrating an example of a discharge means of a first discharge section and a second discharge section. [Diagram 3] FIG. 4 is an explanatory diagram of an example of a coating unit. [Figure 4] FIG. 2 is an explanatory diagram of an example of a drying means of a first drying section and a second drying section. [Diagram 5] FIG. 1 is an illustrative side view of a coating device according to a first embodiment of the present invention. [Figure 6] FIG. 11 is a main part explanatory diagram illustrating an example in which the contact member (defoaming blade) is disposed in a different manner. [Figure 7] FIG. 2 is an explanatory side view of a coating device of Comparative Example 1. [Figure 8] FIG. 4 is an explanatory diagram for explaining the operation of the embodiment. [Figure 9] FIG. 11 is an illustrative side view illustrating the arrangement of a contact member in a coating device according to a second embodiment of the present invention. [Figure 10] FIG. 11 is an illustrative side view of a coating device according to a third embodiment of the present invention. [Figure 11] FIG. 11 is an illustrative side view of a coating device according to a fourth embodiment of the present invention. [Figure 12] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. First, a printing apparatus as a liquid ejecting apparatus according to a first embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a schematic explanatory diagram of the apparatus.

[0011] In this embodiment, the printing device 1 is a device that ejects liquid, and includes an unwinding section 10, an application section 20, a first ejection section 50A, a first drying section 60A, a second ejection section 50B, a second drying section 60B, and a winding section 90.

[0012] The unwinding section 10 is a loading means that unwinds and loads the sheet material P, which is a web such as continuous paper, from a main winding roller 11. The coating section 20 is a pre-treatment means that coats both sides of the sheet material P fed from the unwinding section 10 with a treatment liquid as a coating liquid.

[0013] The first discharge unit 50A is a printing unit including a first discharge means that discharges and prints a liquid including a coloring material onto one side of the sheet material P having treatment liquid applied to both sides thereof by the application unit 20. The first drying unit 60A is a drying unit that heats and dries the sheet material P to which the liquid has been applied by the first discharge unit 50A.

[0014] The second discharge section 50B is a printing means including a second discharge means that discharges and prints a liquid containing a coloring material onto the other side of the sheet material P heated by the first drying section 60A. The second drying section 60B is a drying means that heats and dries the sheet material P to which the liquid has been applied by the second discharge section 50B.

[0015] The winding section 90 is a discharge means for winding up the sheet material P, which has passed through the second drying section 60B and been dried, around a winding roller 91.

[0016] Next, an example of the first and second discharge units will be described with reference to Fig. 2. Fig. 2 is an explanatory diagram of the discharge means of the discharge units.

[0017] The first discharge section 50A and the second discharge section 50B each include a discharge means 500. The discharge means 500 of the first discharge section 50A is referred to as a first discharge means, and the discharge means 500 of the second discharge section 50B is referred to as a second discharge means.

[0018] The ejection means 500 has full line type head arrays 551A, 551B, 551C, and 551D (hereinafter, when no distinction is made between colors, they will be referred to as "head array 551") arranged in order from the upstream side in the transport direction.

[0019] Each head array 551 is a liquid ejection means, and ejects liquid of black K, cyan C, magenta M, and yellow Y onto the conveyed sheet material P. The types and number of colors are not limited to these.

[0020] The head array 551 is, for example, liquid ejection heads (also simply referred to as "heads") 100 arranged in a staggered pattern on a base member 552, but is not limited to this.

[0021] Next, an example of the application unit will be described with reference to Fig. 3. Fig. 3 is an explanatory diagram for explaining the outline of the application unit.

[0022] The coating section 20 includes a first coating means 21A, a second coating means 21B, a plurality of guide rollers 23, and a cutter mechanism 24. In addition, the coating section 20 is provided with an S-shaped conveying path 25 immediately before the exit, thereby improving the running stability of the sheet material P.

[0023] The first application means 21A is a treatment liquid application means that applies, by coating, a treatment liquid 201 as a coating liquid onto one surface (front surface) of the conveyed sheet material P. The second application means 21B is a treatment liquid application means that applies, by coating, the treatment liquid 201 onto the other surface (rear surface) of the sheet material P.

[0024] The treatment liquid 201 used is one that does not significantly change the aggregation reaction with the ink whether it is in a wet state or a dry state. For example, a pre-application liquid such as that shown in JP2019-019315A can be used.

[0025] Next, an example of the drying means constituting the first drying section and the second drying section will be described with reference to Fig. 4. Fig. 4 is an explanatory diagram of the drying means of the drying section. In Fig. 4, rotating bodies having the same function are given the same surface coating and the reference numerals are omitted.

[0026] The first drying section 60A and the second drying section 60B are equipped with drying means 600. The drying means 600 of the first drying section 60A is referred to as a first drying means, and the drying means 600 of the second drying section 60B is referred to as a second drying means.

[0027] The drying means 600 includes a plurality of heating rollers 611 and a heating drum 612 that contact the sheet material P to heat the sheet material P. The drying means 600 also includes a guide roller 613 that guides the sheet material P so that it comes into contact with a desired heating roller 611 among the plurality of heating rollers 611.

[0028] The multiple heating rollers 611, the heating drum 612, and the multiple guide rollers 613 form a heating conveying path (conveying path) for heating the sheet material P. The sheet material P is conveyed while contacting the outer periphery of the multiple heating rollers 611 arranged in an arc shape upstream of the heating drum 612, and then passes through the heating drum 612 and is conveyed by the guide roller 613 while contacting the inner periphery of the multiple heating rollers 611 again.

[0029] That is, in this embodiment, the sheet material P is brought into contact with the heating roller 611 from different directions and heated.

[0030] In addition, in the drying means 600, non-contact heating means 616 for heating the sheet material P from the liquid application surface side is arranged on the outer circumferential side of the arrangement of the multiple heating rollers 611, and multiple non-contact heating means 616 are also arranged around the heating drum 612. The non-contact heating means 616 can be composed of, for example, an air blowing unit, an IR heater, etc. In this embodiment, the "liquid application surface" means a surface onto which the liquid discharged by the discharge means 500 of the first discharge section 50A or the second discharge section 50B is applied.

[0031] Further, a plurality of guide rollers 617 are provided for guiding the sheet material P into the drying means 600 and for guiding the sheet material P out of the drying means 600.

[0032] The drying process in the drying means 600 configured in this manner involves heating the liquid application surface and the opposite surface of the sheet material P while they are in contact with the heating roller 611, and heating the liquid application surface by, for example, blowing air onto the liquid application surface using the non-contact heating means 616.

[0033] Next, the sheet material P is heated while being rolled over the liquid application surface and the opposite surface thereof on a heating drum 612 arranged inside a plurality of heating rollers 611, and the liquid application surface is heated, for example, by blowing air onto the liquid application surface using a non-contact heating means 616.

[0034] Thereafter, while the guide roller 613 is brought into contact with the liquid application surface of the sheet material P, the opposite surface of the sheet material P to the liquid application surface is brought into contact with the heating roller 611 again to heat the sheet material P, thereby drying the liquid applied to the sheet material P.

[0035] At this time, the treatment liquid 201 applied to both sides of the sheet material P by the application unit 20 is also dried, and the treatment liquid 201 becomes dry.

[0036] As described above, the printing apparatus 1 is provided with the coating unit 20 including the first coating means 21A and the second coating means 21B that coat both sides of the sheet material P with the coating liquid (treatment liquid 201).

[0037] The apparatus is equipped with a first discharge section 50A that receives the sheet material P having the treatment liquid 201 applied to both sides thereof by the application section 20 and discharges the liquid onto one side of the sheet material P, and a first drying section 60A that dries the sheet material P to which the liquid has been applied by the first discharge section 50A.

[0038] Furthermore, it is provided with a second discharge section 50B that discharges liquid onto the other side of the sheet material P that has passed through the first drying section 60A, and a second drying section 60B that dries the sheet material P to which the liquid discharged by the second discharge section 50B has been applied.

[0039] In this manner, the coating liquid (treatment liquid 201) is applied to both sides of the sheet material P, and the liquid is discharged onto the sheet material P sent to the first discharge unit 50A, which is the first discharge means, without being heated, for printing, and then dried. As a result, the coating liquid applied to the sheet material P and the printing liquid applied by the first discharge unit 50 are dried.

[0040] Thereafter, liquid is ejected by the second ejection section 50B, which is the second ejection means, onto the other surface of the sheet material P for printing, and then the sheet material P is dried.

[0041] In other words, there is no means for heating the sheet material P between the coating section 20 and the first discharge section 50A, which is the first discharge means, and the first drying section 60A, which is the first drying means, is disposed between the first discharge means and the second discharge means.

[0042] In other words, liquid is ejected from the first ejection section 50A, which is the first ejection means, onto the sheet material P that has been applied with the coating liquid and is not heated, and liquid is ejected from the second ejection section 50B, which is the second ejection means, onto the sheet material P that has been applied with the coating liquid and is heated.

[0043] In addition, the first discharge section 50A, which is the first discharge means, is configured to discharge liquid onto the sheet material P in a wet state, and the second discharge section 50B, which is the second discharge means, is configured to discharge liquid onto the sheet material P in a dry state from the coating liquid.

[0044] This prevents the coating liquid applied to the sheet material P and the printing liquid by the first discharge means from being sent to the second discharge means in a wet state and being further applied with the liquid, thereby improving print quality.

[0045] Next, a coating device according to a first embodiment of the present invention will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is an explanatory side view of the coating device according to the first embodiment, and Fig. 6 is an explanatory side view of the same device for explaining a different example of the arrangement of the contact member (defoaming blade).

[0046] The coating device 200 can constitute the first coating unit 21A and the second coating unit 21B of the coating section 20 in the printing apparatus 1.

[0047] The coating device 200 includes a treatment liquid storage container ( The treatment liquid container 202 may be integrated with the housing of the coating device 200.

[0048] The treatment liquid storage container 202 includes a pumping roller 205 that pumps up the treatment liquid 201, and an application roller 206 that transfers the treatment liquid 201 by the pumping roller 205 and applies the treatment liquid 201 to the sheet material P. The pumping roller 205 is rotated at a speed slightly slower than the conveying speed of the sheet material P.

[0049] The application roller 206 is a coating rotor that applies a coating liquid (treatment liquid 201) to the sheet material P, and the pumping roller 205 is a supply rotor that supplies the treatment liquid 201 to the application roller 206. When an intermediate roller is disposed between the pumping roller 205 and the application roller 206, the intermediate roller that comes into contact with the application roller 206 becomes the supply rotor.

[0050] In addition, a pressure roller 207 is provided to face the application roller 206 and press the sheet material P against the application roller 206. The pressing pressure of the pressure roller 207 can be adjusted by a pressure adjustment device or the like.

[0051] In this coating device 200, a pumping roller 205 transfers (transfers) a treatment liquid 201 onto the surface of a coating roller 206 in the form of a thin film.

[0052] Then, the application roller 206 is pressed against the rotating pressure roller 207 to rotate the application roller 206. At this time, the application device 200 applies the treatment liquid 201 to the surface of the sheet material P by conveying the sheet material P to the nip portion between the application roller 206 and the pressure roller 207.

[0053] The nip pressure (pressure acting at the position where the application roller 206 and the pressure roller 207 contact each other) when applying the treatment liquid 201 can be adjusted by a pressure adjusting device. By changing the nip pressure using the pressure adjusting device, the amount of the treatment liquid 201 applied (application amount, film thickness, liquid amount, adhesion amount, dried adhesion amount, etc.) can be adjusted.

[0054] The amount of treatment liquid 201 applied can also be controlled by changing the rotation speeds of the application roller 206 and the pressure roller 207 .

[0055] The coating device 200 includes a defoaming blade 210 as a contact member that contacts the circumferential surface of the coating roller 206. The defoaming blade 210 contacts the circumferential surface of the coating roller 206 downstream of a coating position a where the coating roller 206 applies the treatment liquid 201 to the sheet material P in the rotation direction of the coating roller 206.

[0056] The defoaming blade 210 comes into contact with the circumferential surface of the applying roller 206 upstream of a supply position b where the applying roller 206 receives the treatment liquid 201 from the draw-up roller 205 in the rotational direction of the applying roller 206 .

[0057] Here, the defoaming blade 210 is disposed so that the distance between the defoaming blade 210 and the circumferential surface of the applying roller 206 gradually narrows. In this embodiment, the defoaming blade 210 is disposed in contact with the applying roller 206 along a tangential direction from the forward direction relative to the rotation direction of the applying roller 206.

[0058] In this embodiment, the defoaming blade 210 is arranged along the vertical direction.

[0059] In addition, the defoaming blade 210 contacts the peripheral surface of the applying roller 206 from the tangential direction at position c where the distance L of the perpendicular line to the line connecting the axis O of the applying roller 206 and the applying position a is the longest in the rotational direction of the applying roller 206.

[0060] Mylar is used as the defoaming blade 210. The rear end of the defoaming blade 210 is fixed to a mounting member 211, and the position is adjusted so that the front end abuts against the circumferential surface of the application roller 206 in the tangential direction. The thickness of the defoaming blade 210 is, for example, 0.188 mm. If the thickness of the defoaming blade 210 is too thick, the contact pressure will be high and the surface of the application roller 206 will be severely worn, and if it is too thin, the contact pressure will be low and the foam-busting function will be weakened.

[0061] Next, the generation of bubbles in Comparative Example 1 will be described with reference to Fig. 7. Fig. 7 is a side view illustrating Comparative Example 1.

[0062] Comparative Example 1 is a coating device that does not include the defoaming blade 210 according to the first embodiment of the present invention.

[0063] In this comparative example 1, while the sheet material P is being coated with the treatment liquid 201 at the nip between the pressure roller 207 and the coating roller 206, if the sheet material P is a paper that is easy for air to pass through, such as plain paper, the small gaps in the paper act like a sponge, and bubbles B are generated.

[0064] The generated foam B is then transported downward by the rotation of the application roller 206, and sent to the treatment liquid storage container 202 where it continues to accumulate. The generated foam B is further increased by being mixed with the treatment liquid 201 pumped up by the pumping roller 205.

[0065] As a result, the liquid level of the processing liquid 201 in the processing liquid storage container 202 rises, causing the processing liquid 201 and the bubbles B to overflow from the processing liquid storage container 202, resulting in a decrease in coating performance.

[0066] Next, the operation of this embodiment will be described with reference to Fig. 8. Fig. 8 is a side view for explaining the operation.

[0067] In this embodiment, a defoaming blade 210 serving as a contact member is brought into contact with the circumferential surface of the application roller 206 .

[0068] Therefore, bubbles B generated when the treatment liquid 201 is applied to the sheet material P by the application roller 206 are transferred by the rotation of the application roller 206 and are crushed and eliminated between the defoaming blade 210 and the application roller 206 .

[0069] This reduces the amount of bubbles B that move into the treatment liquid storage container 202, reduces the amount of the treatment liquid 201 and bubbles B that overflow from the treatment liquid storage container 202, and suppresses a decrease in coating performance.

[0070] Next, a coating device according to a second embodiment of the present invention will be described with reference to Fig. 9. Fig. 9 is a side view illustrating the arrangement of contact members in the coating device according to the second embodiment.

[0071] In this embodiment, the defoaming blade 210 is disposed at an angle in a direction away from the circumferential surface of the application roller 206 with respect to the vertical direction.

[0072] In this case, if the defoaming blade 210 is positioned along the tangential direction, the defoaming blade 210 will contact the peripheral surface of the application roller 206 at position d (position at distance L1) downstream of position c where the distance L of the perpendicular to the line connecting the axis O of the application roller 206 and the application position a is the longest in the rotational direction of the application roller 206.

[0073] Next, a coating apparatus according to a third embodiment of the present invention will be described with reference to Fig. 10. Fig. 10 is a side view of the coating apparatus according to the third embodiment.

[0074] In this embodiment, a discharge hole 220 for discharging bubbles is provided in a part of the treatment liquid storage container 202. The bottom end 220a of the discharge hole 220 is located below the contact position (nip portion) between the draw-up roller 205 and the application roller 206, that is, below the supply position where the treatment liquid 201 is supplied to the application roller 206.

[0075] This allows bubbles that have not been crushed by the defoaming blade 210 to be discharged from the discharge hole 220.

[0076] Next, a coating apparatus according to a fourth embodiment of the present invention will be described with reference to Figures 11 and 12. Figure 11 is an explanatory side view of the coating apparatus according to the fourth embodiment, and Figure 12 is an explanatory front view of the same.

[0077] In this embodiment, a plurality of discharge holes 220 for discharging bubbles are provided in a part of the treatment liquid storage container 202 along the axial direction of the application roller 206. The lower ends 220a of the discharge holes 220 are located below the nip portion (supply position) between the draw-up roller 205 and the application roller 206.

[0078] A duct 221 that is connected to a plurality of discharge holes 220 and guides the discharged foam is disposed on the outside of the treatment liquid storage container 202. The duct 221 has a discharge port 222 that discharges the foam to the outside. An inner bottom surface 221a of the duct 221 is formed as an inclined surface so that the foam can move downward smoothly.

[0079] In each of the above embodiments, an example has been described in which a blade-shaped member is used as the contact member, but a rotating body (defoaming roller) can also be used.

[0080] In the above embodiment, an example of a printing device that prints on a web-like sheet material has been described, but the present invention can also be applied to a printing device that prints on cut sheets, large cut sheets such as wallpaper, etc. The coating device according to the present invention can also be applied to an electrophotographic printing device. [Explanation of symbols]

[0081] 1 Printing device 20 Application section 21A First Coating Means 21B Second coating means 50A First discharge part 50B 2nd discharge part 60A First Drying Section 60B 2nd drying section 200 Coating equipment 201 Processing liquid (coating liquid) 202 Processing liquid storage container (coating liquid storage container) 205 Pumping roller (supply rotor) 206 Coating roller (coating rotating body) 207 Pressure Roller 210 Antifoam blade (contact part) 220 Discharge hole 221 Duct 500 Discharge means 600 Drying means

Claims

1. A coating rotor that applies a coating liquid to a sheet material; a contact member that contacts a peripheral surface of the coating rotary body, The contact member contacts the coating rotor in a tangential direction of the coating rotor downstream of a coating position where the coating liquid is applied in a rotation direction of the coating rotor. A coating device comprising:

2. The contact member is in contact with the coating rotor upstream of a supply position where the coating rotor receives the coating liquid in a rotation direction of the coating rotor. The coating device according to claim 1 .

3. The contact member is disposed so that the distance between the contact member and the peripheral surface of the coating rotary body gradually narrows.

3. The coating device according to claim 1 or 2.

4. The contact member is disposed along the vertical direction. The coating device according to claim 3 .

5. A coating liquid storage container that stores the coating liquid is provided, The coating liquid container is provided with a discharge hole for discharging bubbles to the outside.

5. The coating apparatus according to claim 1, wherein the coating apparatus is a coating apparatus for coating a substrate.

6. The discharge holes are arranged in a plurality of positions in the axial direction of the coating rotor. The coating device according to claim 5 .

7. A coating rotor that applies a coating liquid to a sheet material; a contact member that contacts a peripheral surface of the coating rotary body; a coating liquid storage container that stores the coating liquid, the contact member contacts the coating rotor downstream of a coating position where the coating liquid is applied in a rotation direction of the coating rotor, The coating liquid storage container is provided with a discharge hole for discharging bubbles to the outside, The lowest end of the discharge hole is located below a supply position where the coating rotary body receives the coating liquid. A coating device comprising:

8. A coating rotor that applies a coating liquid to a sheet material; a contact member that contacts a peripheral surface of the coating rotary body; a coating liquid storage container that stores the coating liquid, the contact member contacts the coating rotor downstream of a coating position where the coating liquid is applied in a rotation direction of the coating rotor, The coating liquid storage container is provided with a discharge hole for discharging bubbles to the outside, A duct is provided for guiding the foam discharged from the discharge hole. The coating apparatus according to claim 1,

9. The inner bottom surface of the duct is an inclined surface. The coating device according to claim 8 .

10. A coating apparatus according to any one of claims 1 to 9, and a discharge means for discharging a liquid onto the sheet material. A liquid ejection device comprising:

11. A coating device according to any one of claims 1 to 9, and a printing means for printing on the sheet material. A printing device comprising:

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