Coating device

Abstract

A coating device (1) comprises: a roll (10) that supports an object (W1) to be coated; a die head (15) that is disposed so as to face the roll (10) with a predetermined gap therebetween and that applies a coating liquid (W2) to the object (W1) to be coated; a roll heating unit (20) that is provided in the roll (10) and that heats the roll (10); and a heating unit (26) that heats the die head (15).

Description

Coating device

[0001] The present invention relates to a coating device. This application claims priority based on Japanese Patent Application No. 2024-171010 filed on September 30, 2024, and the contents thereof are incorporated herein by reference.

[0002] Conventionally, coating devices provided with a heating unit for heating a die head are known (see, for example, Patent Documents 1 and 2). In these coating devices, the heating unit heats the coating liquid supplied from the die head, sufficiently reducing the viscosity and shear recovery force of the coating liquid, thereby improving the leveling property (self-leveling property) of the coating film surface immediately after coating and enabling the obtainment of a uniform coating film.

[0003] JP-A-2002-001199 JP-A-07-275774

[0004] One aspect of the coating device of the present invention includes a roll for supporting a workpiece to be coated, a die head arranged to face the roll at a predetermined interval and apply a coating liquid to the workpiece to be coated, a roll heating unit provided on the roll for heating the roll, and a die heating unit provided on the die head for heating the die head.

[0005] It is a cross-sectional view schematically showing a part of the coating device according to an embodiment of the present invention. It is a view taken in the direction of arrow A1 in FIG. 1. It is a cross-sectional view of the main part showing a state where the die head is being cleaned by the cleaning unit in the coating device. It is a view for explaining a state where the cleaning roll is being conveyed by the roll conveying unit in the cleaning unit. It is a view for explaining a state where the coating liquid supply port of the die head is blocked with a plug. It is a plan view showing a state where the die head is being cleaned by the cleaning unit. It is a cross-sectional view taken along the cutting line A3-A3 in FIG. 6. It is a plan view showing another state where the die head is being cleaned by the cleaning unit.

[0006] Hereinafter, an embodiment of the coating apparatus according to the present invention will be described with reference to Figures 1 to 8. The die head 15 shown in Figures 1, 3, 4, 5, and 7 is a cross-sectional view of the die head 15. As shown in Figures 1 to 3, the coating apparatus 1 of this embodiment comprises a roll 10, a die head 15, a roll heating unit 20, a heating unit 26, a chamber 30, a pressure adjustment unit 35, a humidity adjustment unit 40, a gas supply unit 45, a liquid tank 50, a first pipe 55, a second pipe 60, a pump 65, a filter 70, a degassing device 75, a cleaning unit (cleaning unit) 80, and a control unit 100. Note that in Figure 2, the die support unit 18, which will be described later, is shown with hatching, and the heating unit 26 on the back side of the die head 15 is not shown. In Figure 3, the cleaning unit 80 is illustrated with an emphasis on the pipes 82 and 84, which will be described later.

[0007] As shown in Figure 1, for example, the roll 10 is formed in a cylindrical shape from iron or the like. Preferably, a hard chrome plating layer is provided on the outer surface of the roll 10. The roll 10 is arranged so that its axis O1 is aligned with the horizontal plane. However, the orientation in which the roll 10 is arranged is not limited to this. A film (object to be coated) W1 is wound around a portion of the circumferential direction of the roll 10. The roll 10 supports the film W1. In this embodiment, the film W1 is conveyed by the roll 10. The film W1 is supplied and wound up by a known roll-to-roll mechanism (not shown).

[0008] As shown in Figures 1 and 3, the die head 15 has a die body 16 and a projection 17. For example, the die body 16 is formed in a prismatic shape. The die body 16 extends in the direction of the axis O1. The projection 17 protrudes along the horizontal plane from a side surface of the die body 16 that faces in the direction of the horizontal plane. The projection 17 extends in the direction of the axis O1. The die body 16 and projection 17 of the die head 15 are integrally formed from stainless steel or the like. The die head 15 may be positioned such that the projection 17 side is above the die body 16.

[0009] As shown in Figure 3, the die head 15 has a liquid reservoir 15a, a tip-side flow path 15c, two base-side flow paths 15d, and a plurality of through holes 15b. Figures 1, 3, and 4 show four through holes 15b, and each through hole 15b is provided with a heat pipe 27. For example, the liquid reservoir 15a is formed in the center of the die body 16 when viewed in the direction of the axis O1. The tip-side flow path 15c extends from the liquid reservoir 15a along the horizontal plane and penetrates to the protruding portion 17. The vertical width of the tip-side flow path 15c is smaller than the diameter of the liquid reservoir 15a. The tip of the protruding portion 17 in the tip-side flow path 15c is the coating liquid supply port 17a.

[0010] The two base-side flow channels 15d extend from the liquid reservoir 15a toward the opposite side from the tip-side flow channel 15c. The two base-side flow channels 15d are spaced apart from each other in the vertical direction. Multiple through holes 15b penetrate the die head 15 in the direction of the axis O1, and heat pipes 27 are provided within the through holes 15b. The multiple through holes 15b are arranged to surround the liquid reservoir 15a. The number of through holes 15b formed in the die head 15 is not limited.

[0011] Except for the coating liquid supply port 17a, the majority of the surface of the die head 15 is covered by the heating section 26.

[0012] A roll 10 is positioned on the protruding portion 17 side of the die head 15. The die head 15 is positioned opposite the roll 10 at a predetermined distance. The liquid reservoir 15a, the tip-side channel 15c, and the two base-side channels 15d of the die head 15 are filled with coating liquid W2. The die head 15 applies the coating liquid W2 to the film W1.

[0013] Figure 2 is a horizontal view of the die head 15 from the side connected to the first pipe 55 and the second pipe 60. As shown in Figure 2, for example, the die head 15 is horizontally supported from below by the die support portion 18. That is, the die head 15 and the die support portion 18 are arranged in a tandem structure in the vertical direction. In this case, it is preferable that the die head 15 is supported only at both ends in the direction of the axis O1 of the die head 15 by the die support portion 18. With this configuration, a space is created between the die support portion 18 and the die head 15, and the heating portion 26 can be provided in this space. Therefore, the area of ​​the heating portion 26 that covers the surface of the die head 15 can be expanded. Also, the portion of the die head 15 that is in contact with the die support portion 18 cannot be heated by the heating portion 26, so the die support portion 18 is heated, and the die head 15 is heated by the heat transfer. Thus, the entire surface of the die head 15 can be heated by the heating portion 26 and the die support portion 18.

[0014] In this embodiment, the coating apparatus 1 has the die head 15 and the roll 10 arranged horizontally, and the die head 15 is supported from below by the die support part 18, but the configuration is not limited to this. For example, the die head 15, roll 10 and die support part 18 in Figures 1 and 2 may be rotated 90 degrees around an axis parallel to the axis O1 without changing their relative positions, so that the roll 10 is placed directly above the die head 15. Coating in a vertically upward direction from the coating liquid supply port 17a of the die head 15 has the advantage that bubbles in the coating liquid W2 can be easily released.

[0015] As shown in Figure 1, for example, the roll heating unit 20 is located inside the roll 10. In this embodiment, the roll 10 is heated to a uniform temperature by the induction heating type roll heating unit 20. The method by which the roll heating unit heats the roll 10 is not limited. The die head 15 is heated from the surface by the heating unit 26, and also heated from the inside by a plurality of heat pipes 27 so that the temperature in the axial direction O1 is uniform. In this way, the entire die head 15 can be heated to a uniform temperature without any temperature distribution. Furthermore, in the contact area between the die head 15 and the die support unit 18 where the heating unit 26 is not provided, the die head 15 is heated by heating the die support unit 18.

[0016] For example, a heater wire is used in the heating section 26. The heating section 26 is provided on the surface (outer surface) of the die head 15. The heating section 26 heats the surface of the die head 15. A flexible heater can be used as the heating section 26. Multiple heat pipes 27 are arranged in multiple through holes 15b of the die head 15 (inside the die head 15). Each heat pipe 27 extends in the direction of the axis O1. Here, A extending in the direction of B means, for example, that the angle between A and direction B is 30 degrees or less. The die support section 18 is heated by covering the area around the die support section 18 with a flexible heater.

[0017] Each heat pipe 27 transfers heat that has been transferred to one part of it to another part of it. Although not shown in the diagram, two heat pipes 27 arranged horizontally in Figure 1 are connected at a portion of each other, allowing water contained within the two heat pipes 27 to move back and forth. Therefore, heat transfer is accelerated between the two connected heat pipes 27. Note that the orientation of the multiple heat pipes 27 arranged on the die head 15 is not limited to this.

[0018] As described above, the heating unit 26 heats the die head 15 from its surface. This heats the die head 15 and the heat pipe 27 by heat transfer. The heat pipe 27 provides a uniform heating effect to the die head 15, making it easier to control the temperature of the die head 15, which has a large heat capacity. Specifically, the heat pipe 27 allows the die head 15 to quickly rise to a predetermined temperature and maintain a uniform temperature inside the die head 15. The method by which the heating unit 26 heats the die head 15 is not limited.

[0019] Chamber 30 separates the film deposition space S1, which includes the roll 10 and die head 15, from the space outside the film deposition space S1. Pressure adjustment unit 35 increases or decreases the pressure inside chamber 30 to adjust it to a desired pressure. Humidity adjustment unit 40 adjusts the humidity inside chamber 30 to a desired humidity. Gas supply unit 45 supplies gas into chamber 30 to control the film deposition atmosphere. For example, an inert gas is used as the gas supplied to chamber 30. The inert gas can be selected from, for example, nitrogen, helium, neon, argon, krypton, xenon, radon, and carbon dioxide.

[0020] The pressure adjustment unit 35, humidity adjustment unit 40, and gas supply unit 45 allow for the adjustment of the pressure, humidity, and atmosphere, which constitute the film-forming environment within the chamber 30. Since the film-forming environment can be adjusted according to the characteristics of the coating liquid W2, it is possible to form a film with good quality in an appropriate environment.

[0021] The liquid tank 50 contains the coating liquid W2. The first pipe 55 and the second pipe 60 are connected to the liquid tank 50 and the base end side flow path 15d of the die head 15, respectively. The first pipe 55 and the second pipe 60 are different pipes from each other. The second pipe 60 has a first section pipe 61, a second section pipe 62, and an opening / closing section 63.

[0022] The first end of the first section piping 61 is connected to the liquid tank 50. The first end of the second section piping 62 is connected to the base end side flow path 15d of the die head 15. The opening / closing section 63 has a first joint 63a and a second joint 63b. The first joint 63a is provided at the second end of the first section piping 61, which is the end opposite to the first end. The second joint 63b is detachable from the first joint 63a. The second joint 63b is provided at the second end of the second section piping 62, which is the end opposite to the first end. In this example, the second joint 63b is installed inside the chamber 30. The opening / closing section 63 is positioned between the die head 15 and the filter 70, which will be described later, in the first section piping 61 and the second section piping 62.

[0023] As will be described later in Figure 5, when the first joint 63a and the second joint 63b are connected to each other with the coating liquid supply port 17a of the die head 15 blocked by the plug 111, the first partial pipe 61 and the second partial pipe 62 are connected, and the coating liquid W2 flows through the second pipe 60. On the other hand, when the first joint 63a and the second joint 63b are separated from each other, the connection between the first partial pipe 61 and the second partial pipe 62 is released, and the coating liquid W2 does not flow through the second pipe 60. When the connection of the second pipe 60 is released, the first joint 63a blocks the second end of the first partial pipe 61, and the second joint 63b blocks the second end of the second partial pipe 62. As described above, the opening / closing section 63 having the first joint 63a and the second joint 63b controls the flow of the coating liquid W2 through the second pipe 60.

[0024] A pump (water pump) 65 is installed in the first piping 55. The pump 65 sends the coating liquid W2 from the liquid tank 50 toward the die head 15. A filter 70 and a deaeration device 75 are installed in the first section piping 61 of the second piping 60. The filter 70 is located in the first section piping 61 toward the second end side of the deaeration device 75. The filter 70 filters the coating liquid W2 flowing through the first section piping 61 from the die head 15 toward the liquid tank 50. The deaeration device 75 removes air from the coating liquid W2 flowing through the first section piping 61.

[0025] Preferably, heating elements such as heater wires are provided on the outer surfaces of the first pipe 55 and the partial pipes 61 and 62 of the second pipe 60. In Figure 1, region R1 is the area in which the coating liquid W2 is heated by the heating element 26 and the heating elements.

[0026] Figures 3 and 4 show the cleaning unit 80. Note that in Figure 4, the cleaning unit 80 is illustrated with an emphasis on the roll conveying section 87, which will be described later. The cleaning unit 80 cleans the coating liquid supply port 17a of the die head 15. The cleaning unit 80 includes a cleaning roll 81, a gas supply pipe 82, a gas supply device 83, a suction pipe 84, a suction device 85, a gas heating section 86, and a roll conveying section 87 (see Figure 4). The cleaning roll 81 is roll-shaped as shown in Figure 6. In this example, the cleaning roll 81 is formed with a recessed central part in its axial direction so as to engage with the protrusion 17 of the die head 15. That is, the cleaning roll 81 has a small diameter section 90, a first large diameter section 91, and a second large diameter section 92. The first large-diameter section 91, the small-diameter section 90, the gas supply pipe 82, the gas supply device 83, and the gas heating section 86 constitute a cleaning gas supply section 94 that supplies cleaning gas (gas) to the coating liquid supply port 17a from outside the die head 15. The second large-diameter section 92, the suction pipe 84, and the suction device 85 constitute a suction section 95 that sucks up the cleaning gas and dirt from the coating liquid supply port 17a. In other words, the cleaning unit 80 includes a cleaning gas supply section 94 and a suction section 95.

[0027] The small-diameter portion 90, the first large-diameter portion 91, and the second large-diameter portion 92 are each formed in a cylindrical shape. The diameters of the first large-diameter portion 91 and the second large-diameter portion 92 are larger than the diameter of the small-diameter portion 90. The first large-diameter portion 91 and the second large-diameter portion 92 are arranged so as to sandwich the small-diameter portion 90. For example, the small-diameter portion 90, the first large-diameter portion 91, and the second large-diameter portion 92 are integrally formed from a porous material. The small-diameter portion 90, the first large-diameter portion 91, and the second large-diameter portion 92 each have a plurality of holes 90a, 91a, and 92a formed therein. The small-diameter portion 90, the first large-diameter portion 91, and the second large-diameter portion 92 can be formed from a metallic material such as stainless steel, or a resin material such as polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), or tetrafluoroethylene-perfluoromethyl vinyl ether rubber (FFKM).

[0028] The first end of the gas supply pipe 82 is connected to the first large-diameter section 91. The pipeline of the gas supply pipe 82 is connected to a plurality of holes 91a in the first large-diameter section 91 and holes 90a in the small-diameter section 90. The gas supply device 83 is connected to the second end of the gas supply pipe 82, which is the end opposite to the first end. The gas supply device 83 supplies cleaning gas to the gas supply pipe 82. For example, nitrogen gas can be used as the cleaning gas. The cleaning gas is sprayed from the plurality of holes 91a and the plurality of holes 90a into the coating liquid supply port 17a of the die head 15. The first end of the suction pipe 84 is connected to the second large-diameter section 92. The pipeline of the suction pipe 84 is connected to a plurality of holes 92a in the second large-diameter section 92. The suction device 85 is connected to the second end of the suction pipe 84, which is the end opposite to the first end. The suction device 85 sucks the cleaning gas in the suction pipe 84, for example, by reducing the pressure. By blowing cleaning gas, the clumps of coating liquid W2 that were stuck to the coating liquid supply port 17a are removed from the coating liquid supply port 17a and sucked out through the multiple holes 92a of the second large diameter portion 92.

[0029] Although not shown in the diagram, it is more preferable that the sizes of the multiple holes 91a and 90a are smaller than the multiple holes 92a. Since a forceful gas is blown from the multiple holes 91a and 90a into the coating liquid supply port 17a, the diameter of the holes is reduced to increase the gas pressure. In contrast, the diameter of the multiple holes 92a is increased so that the removed solid material can be quickly aspirated.

[0030] For example, the gas heating unit 86 is a heater wire and is provided on the surface of the gas supply pipe 82. The gas heating unit 86 heats the cleaning gas inside the gas supply pipe 82 through the gas supply pipe 82. As described above, the cleaning unit 80 supplies heated gas from the cleaning gas supply unit 94. By using heated gas for cleaning, it is possible to prevent the set temperature of the die head 15 from dropping due to cleaning. Therefore, the cleaning process can be performed without a drop in the temperature of the die head 15, and the coating downtime due to cleaning can be shortened. Preferably, the temperature of the cleaning gas is the same as the set temperature of the die head 15.

[0031] As shown in Figure 4, for example, the roll conveying unit 87 is composed of a known robot arm. The first end of the roll conveying unit 87 is fixed to the support unit 97. A washing roll 81 is attached to the second end of the roll conveying unit 87, which is the end opposite to the first end. The roll conveying unit 87 conveys the washing roll 81. As shown in Figure 3, when the cleaning unit 80 cleans the coating liquid supply port 17a of the die head 15, the small diameter portion 90 of the washing roll 81 faces the coating liquid supply port 17a of the die head 15, and the first large diameter portion 91 and the second large diameter portion 92 clamp the protruding portion 17 of the die head 15 in a direction intersecting the direction in which the protruding portion 17 protrudes.

[0032] The control unit 100, although not shown in the figures, includes a CPU (Central Processing Unit), memory, etc. The control unit 100 is connected to the roll-to-roll mechanism, the roll heating unit 20, the heating unit 26, the pressure adjustment unit 35, the humidity adjustment unit 40, the gas supply unit 45, the opening / closing unit 63, the pump 65, the gas supply device 83, the suction device 85, the gas heating unit 86, and the roll transport unit 87. The control unit 100 controls the roll-to-roll mechanism, the roll heating unit 20, the heating unit 26, the pressure adjustment unit 35, the humidity adjustment unit 40, the gas supply unit 45, the opening / closing unit 63, the pump 65, the gas supply device 83, the suction device 85, the gas heating unit 86, and the roll transport unit 87.

[0033] Next, the operation of the coating apparatus 1 configured as described above will be explained. As shown in Figure 5, the control unit 100 pre-drives the transport device 110 to close the coating liquid supply port 17a of the die head 15 with a plug 111. For example, the plug 111 is made of rubber. Next, for example, the control unit 100 drives the pressure adjustment unit 35 and the humidity adjustment unit 40 to set the pressure and humidity in the chamber 30 to desired values. After that, the gas supply unit 45 is driven to supply, for example, an inert gas into the chamber 30. The opening / closing unit 63 is driven to allow the coating liquid W2 to flow through the second pipe 60. The roll heating unit 20 is driven to heat the roll 10, and the heating unit 26 is driven to heat the die head 15. The pipe heating unit is driven to heat the first pipe 55 and the second pipe 60 as appropriate. In this way, the coating liquid W2 is heated. This brings the coating liquid W2 to a constant temperature. Furthermore, the die head 15 and the roll 10 are kept at a uniform temperature so as not to have any temperature variations, and the distance between the die head 15 and the roll 10 is kept constant.

[0034] The heating temperature of each component depends on the properties of the coating liquid W2, but here we will describe an example of the temperature at which each component is heated. For example, the roll 10 is heated to 100°C. The die head 15 and the multiple heat pipes 27 are heated to 80°C. The coating liquid W2 is heated to 70°C.

[0035] The control unit 100 drives the pump 65 to send the heated coating liquid W2 in the following order: first pipe 55, die head 15, second pipe 60, and liquid tank 50. The coating liquid W2 is filtered by the filter 70 and the air is removed by the deaeration device 75. Once the coating liquid W2 has been heated to a certain temperature, the roll-to-roll mechanism is driven to rotate the roll 10 in a predetermined direction around the axis O1. The conveying device 110 is driven to remove the plug 111 of the coating liquid supply port 17a and open the coating liquid supply port 17a of the die head 15. The opening / closing unit 63 is driven to prevent the coating liquid W2 from flowing through the second pipe 60.

[0036] The coating liquid W2 supplied from the coating liquid supply port 17a of the die head 15 is applied to the film W1 supported by the roll 10. The coating liquid W2 applied to the film W1 is quickly dried by the heat generated by the heated roll 10 and the heated coating liquid W2 itself. The coating liquid W2 on the film W1 dries from the side of the heated roll 10, that is, from the bottom surface of the film. Therefore, the adhesion between the film W1 and the formed film is better than if the coating liquid W2 on the film W1 were dried from the top side. This is because if drying is performed from the top surface of the formed film, solvent tends to remain on the film W1 side, impairing the adhesion between the film W1 and the film.

[0037] After coating and forming the film in chamber 30, the film W1 is transported to a heating chamber to completely evaporate the solvent. The pressure and humidity inside chamber 30 are set to desired values. Furthermore, if an inert gas is supplied into chamber 30, oxidation of the coating liquid W2 is suppressed. In this case, since the coating liquid W2 does not pass through the filter 70 and the degassing device 75, the pressure loss caused by the flow of the coating liquid W2 is reduced.

[0038] For example, after applying the coating liquid W2 to the film W1 for a certain period of time, the control unit 100 cleans the coating liquid supply port 17a of the die head 15 using the cleaning unit 80 as follows. The gas heating unit 86 is driven in advance to heat the gas supply pipe 82 and the cleaning gas inside the gas supply pipe 82. As shown in Figures 6 and 7, the roll transport unit 87 is driven to position the cleaning roll 81 opposite the coating liquid supply port 17a of the die head 15 at the first end in the axial direction O1 of the coating liquid supply port 17a of the die head 15. Note that the roll transport unit 87 is schematically shown in Figure 6 and Figure 8, which will be described later. As shown in Figures 6 and 7, it is preferable to observe the cleaned coating liquid supply port 17a of the die head 15 using the cube mirror 150 and the camera 151 at this time.

[0039] The gas supply device 83 is driven to supply cleaning gas to the gas supply pipe 82, and the suction device 85 is driven to suck up the removed clumps of coating liquid. The heated cleaning gas is blown out from multiple holes 91a in the first large diameter section 91 and multiple holes 90a in the small diameter section 90 of the cleaning roll 81, and dirt and other contaminants adhering to the coating liquid supply port 17a of the die head 15 are peeled off from the coating liquid supply port 17a. Because the cleaning gas is heated, the temperature drop of the die head 15 during cleaning is suppressed, and furthermore, the cooling of the coating liquid W2 inside the die head 15 is suppressed. The peeled-off dirt and other contaminants and the cleaning gas that has cleaned the coating liquid supply port 17a are sucked into the suction device 85 through multiple holes 92a in the second large diameter section 92 of the cleaning roll 81 and the suction pipe 84.

[0040] As shown in Figure 8, the cleaning roll 81 moves along the coating liquid supply port 17a of the die head 15 by driving the roll transport unit 87. In this way, the coating liquid supply port 17a is cleaned over its entire width in the direction of the axis O1.

[0041] In the coating apparatuses described in Patent Documents 1 and 2, there is room for improvement in maintaining a constant gap between the roll and the die head. Maintaining a constant gap between the roll and the die head directly contributes to improving the accuracy of film formation. However, in coating apparatuses that perform coating while heating, it has been difficult to maintain a constant gap between the roll and the die head across the width of the substrate due to temperature inconsistencies in the substrate stage, die head, and coating solution.

[0042] In contrast, in the coating apparatus 1 of this embodiment, for example, the entire roll 10 is heated uniformly and to a constant temperature by the roll heating section 20, and the entire die head 15 is heated uniformly and to a constant temperature close to the temperature of the roll 10 by the heating section 26 and heat pipe 27. This makes it possible to reduce the temperature difference between the roll 10 and the die head 15 compared to when only one of the roll 10 or the die head 15 is heated. As a result, the amount of heat transferred between the roll 10 and the die head 15 is relatively small, and the roll 10 and the die head 15 are less likely to deform due to heat transfer. Consequently, the distance between the roll 10 and the die head 15 can be easily kept constant. Furthermore, since there is no temperature non-uniformity in either the roll 10 or the die head 15, there is no difference in thermal expansion depending on the location, and a constant distance can be created across the width direction (axis O1 direction) of the film W1.

[0043] Furthermore, even if the coating liquid W2 has high viscosity at room temperature and is difficult to coat, heating the roll 10 and die head 15 can lower the viscosity of the coating liquid W2, making coating possible. In addition, even if the coating liquid W2 does not dissolve at room temperature, it can be dissolved by raising the temperature of the solvent, thus enabling the coating of materials that were previously difficult to coat.

[0044] The coating apparatus 1 includes a cleaning unit 80, and the cleaning unit 80 includes a cleaning gas supply unit 94 and a suction unit 95. By supplying cleaning gas to the coating liquid supply port 17a by the cleaning gas supply unit 94 and sucking the cleaning gas that has cleaned the coating liquid supply port 17a by the suction unit 95, the coating liquid supply port 17a of the die head 15 can be cleaned. The cleaning unit 80 supplies the cleaning gas heated by the cleaning gas supply unit 94. Therefore, even when the coating liquid W2 has a high viscosity at room temperature, for example, the temperature of the coating liquid W2 filled in the coating liquid supply port 17a to be cleaned by the cleaning gas can be suppressed from decreasing, and the viscosity of the coating liquid W2 can be lowered. Also, by using the heated gas for cleaning, it is possible to prevent the set temperature of the die head 15 from decreasing due to cleaning. Therefore, the cleaning process can be performed without worrying about the temperature drop of the die head 15, and thus no time is required to adjust the temperature setting of the die head 15 in the coating process after cleaning.

[0045] The heating unit 26 heats the die head 15 from the surface, and heats the die head 15 more uniformly in temperature from the inside by a plurality of heat pipes 27. Therefore, the temperature of the die head 15 can be made uniform and constant. The die support portion 18 also contributes to the heating of the die head 15. The coating apparatus 1 includes a chamber 30. Therefore, for example, the pressure in the film formation space S1 including the roll 10 and the die head 15, the gas filled in the film formation space S1, etc. can be easily adjusted.

[0046] The coating apparatus 1 includes a pressure adjustment unit 35 and a gas supply unit 45. Therefore, the pressure adjustment unit 35 can adjust the pressure inside the chamber 30, and the gas supply unit 45 can supply gas into the chamber 30. The coating apparatus 1 includes a liquid tank 50, a first pipe 55, a second pipe 60, a pump 65, and a filter 70. Therefore, for example, by driving the pump 65 with the second pipe 60 connected to the die head 15, the coating liquid W2 flowing through the second pipe 60 can be filtered by the filter 70. And by driving the pump 65 with the second pipe 60 removed from the die head 15, since the coating liquid W2 does not flow through the filter 70, the pressure loss of the coating liquid W2 flowing into the die head 15 can be reduced.

[0047] The second pipe 60 has an opening / closing part 63. Therefore, the opening / closing part 63 can switch the second pipe 60 between a state where the coating liquid W2 flows through it and a state where the coating liquid W2 does not flow through it.

[0048] As described above, one embodiment of the present invention has been described in detail with reference to the drawings, but the specific configuration is not limited to this embodiment, and configurations such as changes, combinations, deletions, etc. within the scope not departing from the gist of the present invention are also included. For example, in the above embodiment, the cleaning unit 80 may not have a gas heating part 86. The second pipe 60 may not have an opening / closing part 63.

[0049] The coating apparatus 1 may not include at least one of the chamber 30, the pressure adjustment unit 35, the humidity adjustment unit 40, the gas supply unit 45, the liquid tank 50, the first pipe 55, the second pipe 60, the pump 65, the filter 70, the degassing device 75, the cleaning unit 80, and the control unit 100. When the coating apparatus 1 does not include the control unit 100, operations such as those of the pressure adjustment unit 35 are performed by an operator who operates the coating apparatus 1.

[0050] (Note) (1) Embodiment 1 of the present invention is a coating apparatus comprising: a roll for supporting a workpiece to be coated; a die head positioned opposite the roll at a predetermined distance and for applying a coating liquid to the workpiece to be coated; a roll heating unit provided on the roll for heating the roll; and a heating unit for heating the die head. (2) Embodiment 2 of the present invention is the coating apparatus described in (1), further comprising a cleaning unit for cleaning the coating liquid supply port of the die head, wherein the cleaning unit comprises a gas supply unit and a suction unit.

[0051] (3) Embodiment 3 of the present invention may be the coating apparatus described in (2), wherein the cleaning unit is supplied with heated gas from the gas supply unit. (4) Embodiment 4 of the present invention may be the coating apparatus described in any one of (1) to (3), wherein the die head is equipped with a heat pipe located inside the die head.

[0052] (5) Embodiment 5 of the present invention may be a coating apparatus according to any one of (1) to (4), comprising a die support portion for supporting the die head. (6) Embodiment 6 of the present invention may be a coating apparatus according to any one of (1) to (4), comprising an enclosure portion for separating the film-forming space including the roll and the die head from the space other than the film-forming space. (7) Embodiment 7 of the present invention may be a coating apparatus according to any one of (1) to (5), comprising a pressure adjustment portion for adjusting the pressure in the chamber, or a gas supply portion for supplying gas into the chamber.

[0053] (8) Embodiment 8 of the present invention may be the coating apparatus according to any one of (1) to (7), comprising a liquid tank for containing the coating liquid, and a first pipe and a second pipe connected to the liquid tank and the die head, respectively, wherein the first pipe is provided with a pump for sending the coating liquid from the liquid tank to the die head, and the second pipe is provided with a filter for filtering the coating liquid flowing from the die head to the liquid tank. (9) Embodiment 9 of the present invention may be the coating apparatus according to (8), wherein the second pipe is provided with an opening / closing section between the die head and the filter for controlling the flow of the coating liquid.

[0054] 1 Coating apparatus 10 Roll 15 Die head 17a Coating liquid supply port 18 Die support section 20 Roll heating section 25 Die heating section 26 Heating section 27 Heat pipe 30 Chamber 35 Pressure adjustment section 45 Gas supply section 50 Liquid tank 55 First piping 60 Second piping 63 Opening / closing section 65 Pump 70 Filter 80 Cleaning unit (cleaning section) 94 Cleaning gas supply section 95 Suction section S1 Film formation space W1 Film (object to be coated) W2 Coating liquid

Claims

1. A coating apparatus comprising: a roll for supporting an object to be coated; a die head positioned opposite the roll at a predetermined distance and for applying a coating liquid to the object to be coated; a roll heating unit provided on the roll for heating the roll; and a heating unit for heating the die head.

2. The coating apparatus according to claim 1, further comprising a cleaning unit for cleaning the coating liquid supply port of the die head, wherein the cleaning unit comprises a gas supply unit and a suction unit.

3. The coating apparatus according to claim 2, wherein the cleaning unit is supplied with heated gas from the gas supply unit.

4. The coating apparatus according to claim 1, wherein the die head comprises a heat pipe disposed inside the die head.

5. The coating apparatus according to claim 1, further comprising a die support portion for supporting the die head, wherein the entire surface of the die head is covered by the heating portion and the die support portion, and the die support portion heats the die head.

6. The coating apparatus according to claim 1, further comprising a chamber that separates the film deposition space, including the roll and the die head, from a space other than the film deposition space.

7. The coating apparatus according to claim 6, further comprising a pressure adjustment unit for adjusting the pressure in the chamber, or a gas supply unit for supplying gas into the chamber.

8. The coating apparatus according to claim 1, comprising a liquid tank for containing the coating liquid, and a first pipe and a second pipe connected to the liquid tank and the die head, respectively, wherein the first pipe is provided with a pump for sending the coating liquid from the liquid tank to the die head, and the second pipe is provided with a filter for filtering the coating liquid flowing from the die head to the liquid tank.

9. The coating apparatus according to claim 8, wherein the second piping includes an opening / closing section between the die head and the filter for controlling the flow of the coating liquid.

Images