Coating device and coating method

Abstract

To provide a coating device and a coating method which reduce variations in a coated film state on ends in a width direction of a specific part of a base material.SOLUTION: A coating device 20 includes first and second blocks 21 and 22 which coat a coating liquid C to both surfaces of a base material 2 and are opposite to each other in a thickness direction of the base material, and a liquid reservoir part 23 which accumulates the coating liquid in a gap between the first and second blocks and passes the base material therethrough. The liquid reservoir part includes an introduction port to which the base material is introduced, a discharge port 25 to which the base material is discharged, and side face parts 26 positioned on both sides in a width direction. In the side face parts, exposure ports 29 opened from the base material introduction port to the base material discharge port are provided. A part of the coating liquid in the width direction of the base material can be projected to the outside of the liquid reservoir part from the exposure ports. In the vicinity of the exposure ports in the width direction, a coating liquid suppression part 50 for suppressing spread of the coating liquid coated onto the base material to the outside in the width direction is provided. The coating liquid suppression part is provided from the introduction port to the discharge port in the conveyance direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a coating device and a coating method. [Background technology]

[0002] For example, various techniques have been disclosed regarding coating devices for forming coating films on both sides of a sheet-like substrate transported by a roll-to-roll method.

[0003] For example, in the coating device disclosed in Patent Document 1, first, a continuously conveyed long sheet-like substrate is immersed in an immersion tank in which the coating liquid is stored, so that the coating liquid is applied to both sides of the substrate. Then, while the substrate is raised vertically, a pair of scraping rolls scrapes off excess coating liquid on both sides of the substrate. This forms a coating film of a certain thickness on both sides of the substrate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 64-7965 Summary of the Invention [Problem to be solved by the invention]

[0005] However, there are cases where it is desired to selectively form a coating film on both sides of a specific portion in the width direction of a substrate. In this case, it is necessary to apply a coating liquid to both sides of the specific portion in the width direction of the substrate while not applying the coating liquid to portions other than the specific portion.

[0006] However, when attempting to selectively form a coating film on both sides of a specific portion of a substrate in the width direction using the coating device of Patent Document 1, it is necessary to adjust the orientation of the substrate itself and the conveying direction of the substrate so that only the specific portion of the substrate is immersed in the immersion tank, which poses the problem of complicating the coating process and requiring an increased size of the coating device.

[0007] The present disclosure has been made in consideration of these points, and its purpose is to selectively form a coating film on both sides of a specific portion in the width direction of a substrate being transported, and to reduce variation in the coating film condition at the width direction ends of the specific portion. [Means for solving the problem]

[0008] A coating device according to the present disclosure is a coating device that applies a coating liquid to both sides of a sheet-like substrate being transported, and includes a pair of blocks facing each other in a thickness direction of the substrate, and a liquid pooling portion formed so that the coating liquid pools in a gap between the pair of blocks and through which the substrate passes, the liquid pooling portion having a substrate inlet opening on the upstream side in a transport direction of the substrate and through which the substrate is introduced, and a substrate outlet opening on the downstream side in the transport direction and through which the substrate is discharged, the liquid pooling portion being positioned on both sides in a width direction intersecting with the transport direction. and a side portion on which the substrate is placed, wherein at least one of the side portions in the width direction has an exposed opening that opens from the substrate inlet to the substrate outlet, and a part of the substrate in the width direction can protrude from the exposed opening to the outside of the liquid pool portion, and a coating liquid suppressing portion is provided near the exposed opening in the width direction to suppress outward spread of the coating liquid applied to the substrate in the width direction, and the coating liquid suppressing portion is provided from the substrate inlet side to the substrate outlet side in the transport direction.

[0009] The coating method according to the present disclosure uses the coating device to pass the substrate through the liquid pool while a portion of the substrate in the width direction protrudes from the exposed opening to the outside of the liquid pool, thereby applying the coating liquid to both surfaces of a specific portion of the substrate in the width direction, and suppressing, by the coating liquid suppression section, the coating liquid applied to the substrate from spreading outward in the width direction in the vicinity of the exposed opening in the width direction. Effect of the Invention

[0010] According to the present disclosure, it is possible to selectively form a coating film on both sides of a specific portion in the width direction of a substrate being transported, and to reduce variation in the coating film condition at the width direction ends of the specific portion. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating a coating system including a coating device according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a front view of the coating device according to the first embodiment. [Diagram 3] FIG. 3 is a plan view of the coating device according to the first embodiment. [Figure 4] FIG. 4 is a side view of the coating device according to the first embodiment. [Diagram 5] FIG. 5 is an enlarged front view showing the vicinity of a substrate discharge port of the coating device according to the first embodiment. [Figure 6] FIG. 6 is a side view of a coating device according to the second embodiment. [Figure 7] FIG. 7 is a side view of a coating device according to the third embodiment. [Figure 8] FIG. 8 is a side view of a coating device according to the fourth embodiment. [Figure 9] FIG. 9 is a side view of a coating device according to the fifth embodiment. [Figure 10] FIG. 10 is a side view of a coating device according to the sixth embodiment. [Figure 11] FIG. 11 is a side view of a coating device according to the seventh embodiment. [Figure 12] FIG. 12 is a plan view of a coating device according to the seventh embodiment. [Figure 13] FIG. 13 is a side view of a coating device according to the eighth embodiment. [Figure 14] FIG. 14 is a plan view of a coating device according to the eighth embodiment. [Figure 15] FIG. 15 is a side view of a coating device according to the ninth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. The following description of the preferred embodiments is merely illustrative in nature and is not intended to limit the present disclosure, its application, or its uses.

[0013] <First embodiment> (Basic configuration) FIG 1 shows a schematic diagram of a coating system 1 according to a first embodiment of the present disclosure. Note that a surface treatment section 51 (coating fluid suppression section 50), which will be described later, is omitted from FIG 1. The coating system 1 is for continuously forming a coating film F on both sides of a substrate 2. The coating system 1 is composed of a substrate supplying device 10, a coating device 20, and a coating fluid supplying device 40.

[0014] The substrate 2 is formed in a long sheet shape. Examples of the substrate 2 include metal foil, resin film, woven fabric, nonwoven fabric, paper, etc. The thickness dimension t (see FIG. 5) of the substrate 2 not including the coating film F is, for example, 1 mm or less.

[0015] The base material supplying device 10 continuously transports the base material 2 by a roll-to-roll method with its longitudinal direction being the transport direction (indicated by X). Specifically, the base material supplying device 10 continuously transports the base material 2 by unwinding the base material 2 with an unwinder 11 and winding it with a winder 12. The transported base material 2 passes through a first roll 13 and a second roll 14 along the way.

[0016] A coating device 20 is disposed between the first roll 13 and the second roll 14 in the transport direction of the substrate 2. The coating device 20, which will be described in detail later, applies a coating liquid C to both sides of the sheet-like substrate 2 that is continuously transported, to form a coating film F on both sides of the substrate 2. The substrate 2 with the coating film F formed on both sides by the coating device 20 is dried in a drying furnace (not shown) to remove volatile components contained in the coating film F, and then taken up by a winder 12.

[0017] The configuration of the coating device 20 will be described in detail. Figures 2 to 5 show the coating device 20 according to this embodiment, with Figure 2 being a front view (viewed in the direction of arrow II), Figure 3 being a plan view (viewed in the direction of arrow III), Figure 4 being a side view (viewed in the direction of arrow IV), and Figure 5 being an enlarged front view of the vicinity of a substrate discharge port 25 described later. Note that in Figure 5, a surface treatment section 51 (coating fluid suppression section 50) described later is omitted from illustration.

[0018] In this embodiment, the conveying direction (longitudinal direction) and the width direction (indicated by Y) of the substrate 2 are horizontal directions. The width direction of the substrate 2 intersects, specifically, is perpendicular to, the conveying direction of the substrate 2. The thickness direction (indicated by Z) of the substrate 2 is vertical.

[0019] 2, the coating device 20 includes a pair of blocks, specifically a first block 21 and a second block 22. The first block 21 and the second block 22 are disposed at a predetermined interval from each other in the thickness direction of the substrate 2 and face each other in the thickness direction of the substrate 2. Each of the blocks 21, 22 is formed in a substantially rectangular parallelepiped shape and disposed such that its longitudinal direction is aligned with the transport direction of the substrate 2.

[0020] 3 and 4, L1 is the length dimension of each of the blocks 21 and 22. L2 is the width dimension of each of the blocks 21 and 22. L3 is the thickness dimension of each of the blocks 21 and 22. It is preferable that the length dimension L1 of each of the blocks 21 and 22 is sufficiently larger (for example, 100 times or more) than the thickness dimension t (see FIG. 5) of the base material 2. In this embodiment, as shown in FIG. 4, the width dimension L2 of each of the blocks 21 and 22 is smaller than the width dimension B of the base material 2.

[0021] 2, in the gap 23 between the pair of blocks, i.e., the gap 23 between the first block 21 and the second block 22, a liquid reservoir is formed so that the coating liquid C can be accumulated (hereinafter, referred to as the "liquid reservoir 23"). When the substrate 2 passes through the liquid reservoir 23, the coating liquid C is applied to both sides of the substrate 2, and a coating film F is formed on both sides of the substrate 2.

[0022] The coating liquid C is preferably in the form of a paste or a slurry. The viscosity η of the coating liquid C is preferably 1 mPa·s or more, and more preferably 1 Pa·s to 1000 Pa·s. For example, the coating liquid C may be an insulating material containing metal oxide particles such as silica, low-melting glass, alumina, titanium oxide, etc., metal particles such as solder, copper, silver, metal-coated particles, etc., a conductive material containing lithium nickel oxide, lithium manganate, lithium cobalt oxide, carbon, etc., a dye, etc.

[0023] H indicates the gap dimension between the first block 21 and the second block 22. The gap dimension H is larger than the thickness dimension t (e.g., 0.1 mm or less) of the base material 2 so that the base material 2 can pass through. The gap dimension H should be as small as possible, and is preferably 0.1 mm or more and 1 mm or less.

[0024] The liquid reservoir 23 includes a substrate inlet 24 that opens on the upstream side (left side in FIG. 2) in the transport direction of the substrate 2, and a substrate outlet 25 that opens on the downstream side (right side in FIG. 2) in the transport direction of the substrate 2. The substrate inlet 24 and the substrate outlet 25 face each other in the transport direction. The substrate 2 is introduced from the substrate inlet 24, passes through the liquid reservoir 23, and is discharged from the substrate outlet 25.

[0025] 3 and 4, the liquid reservoir 23 includes side portions 26 located on both sides in the width direction of the substrate 2. The side portions 26 refer to surfaces extending in the transport direction and thickness direction that constitute the width direction ends of the liquid reservoir 23. The side portion 26 is composed of a first side portion 26a on one side in the width direction (left side in FIG. 4) and a second side portion 26b on the other side in the width direction (right side in FIG. 4). The first side portion 26a and the second side portion 26b face each other in the width direction.

[0026] As shown in Fig. 4, an exposure opening 29 is provided in each of the side surface portions 26 on both sides in the width direction, i.e., the first side surface portion 26a and the second side surface portion 26b. Each exposure opening 29 is open from the base material inlet 24 side (upstream side) to the base material outlet 25 side (downstream side) in each of the first side surface portion 26a and the second side surface portion 26b (see Fig. 2). That is, the first side surface portion 26a and the second side surface portion 26b are open.

[0027] As shown in FIG. 4, a part of the base material 2 in the width direction can protrude from the exposure opening 29 to the outside of the liquid reservoir .

[0028] 2 and 4, a coating liquid supply port 30 is provided on an inner surface 35 of the first block 21 facing the liquid pool 23. The coating liquid supply port 30 faces the liquid pool 23 and supplies the coating liquid C to the liquid pool 23.

[0029] 2 to 4, a plurality of coating liquid supply ports 30 (e.g., three ports) are arranged in the widthwise center of first block 21, lined up in the transport direction. The number of coating liquid supply ports 30 may be one. The cross-sectional shape of coating liquid supply port 30 is, for example, circular or elliptical. The diameter of coating liquid supply port 30 is preferably 1 mm or greater. The cross-sectional shape of coating liquid supply port 30 may be, for example, an elongated hole extending in the transport direction.

[0030] The coating fluid supplying device 40 (see FIG. 1) is a device for supplying the coating fluid C to the coating device 20, and is composed of a coating fluid supply pump 41 and a coating fluid supply pipe .

[0031] 2 and 4, a coating liquid supply path 32 is provided inside first block 21. Coating liquid supply path 32 communicates with a coating liquid supply pump 41 via a coating liquid supply pipe 42 on its upstream side, and communicates with a coating liquid supply port 30 on its downstream side.

[0032] It is preferable to adopt a pump capable of supplying a fixed amount of liquid, such as a screw pump, a diaphragm pump, a syringe pump, a mono pump, or a tube pump, as the coating liquid supply pump 41. Instead of using the coating liquid supply pump 41, compressed air may be introduced into a supply tank to pressure-feed the coating liquid.

[0033] Although not shown, the coating device 20 may include a coating fluid discharge section. The coating fluid discharge section removes the coating fluid C accumulated in the fluid reservoir section 23 when coating is stopped.

[0034] It is preferable that the amount of coating liquid C supplied to the liquid pool 23 through the coating liquid supply port 30 approximately matches the amount of coating liquid C (coating film F) discharged together with the substrate 2 from the liquid pool 23 through the substrate discharge port 25. Excess coating liquid C in the liquid pool 23 may be discharged from the liquid pool 23 by the coating liquid discharge portion.

[0035] The coating fluid discharge section may have a coating fluid pressure adjustment function. In this case, the coating fluid discharge section (coating fluid pressure adjustment function) reduces fluctuations in the pressure of the coating fluid C in the fluid reservoir 23. The coating fluid discharge section may be configured by connecting a coating fluid discharge port provided on the inner surface 35 of each block 21, 22 facing the fluid reservoir 23 to a buffer tank, a leak valve, or the like.

[0036] Regarding the discharge of the coating liquid C, the coating liquid discharge port may be shaped to reduce pressure loss so that the coating liquid C in the liquid reservoir 23 is discharged naturally, or it may be actively sucked out by a suction device.

[0037] In order for the coating liquid C supplied from the coating liquid supply port 30 on the first block 21 side to penetrate the substrate 2 in the thickness direction and flow around to the second block 22 side, the substrate 2 preferably includes a communication portion that allows the coating liquid C to flow in the thickness direction. Specifically, the substrate 2 may be made of, for example, a punched metal, or formed into a comb-tooth or ladder shape, or formed into a mesh shape. The substrate 2 may also be made of a porous material. The substrate 2 may be flat and not include a communication portion.

[0038] As shown in Fig. 4, a coating liquid suppressing section 50 is provided near the exposed opening 29 in the width direction. Specifically, the coating liquid suppressing section 50 is provided near the exposed opening 29 on both sides in the width direction (the first side surface portion 26a side and the second side surface portion 26b side). As shown in Figs. 2 and 3, the coating liquid suppressing section 50 is provided from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the transport direction. The coating liquid suppressing section 50 suppresses the coating liquid C applied to the substrate 2 from spreading outward in the width direction.

[0039] Here, "vicinity of exposed opening 29 in the width direction" refers to region R from slightly inside exposed opening 29 to slightly outside exposed opening 29 in the width direction. "Slightly inside exposed opening 29" refers to, for example, a portion that is 20% of the width dimension L2 inside exposed opening 29 (width direction end of liquid reservoir 23) in the width direction. "Slightly outside exposed opening 29" refers to, for example, a portion that is 20% of the width dimension L2 outside exposed opening 29 (width direction end of liquid reservoir 23) in the width direction.

[0040] In this embodiment, the coating fluid suppression section 50 is composed of a surface treatment section 51 serving as a contact angle changing section. As shown in Fig. 4, the surface treatment section 51 is provided in a portion including an edge (corner) 36 on the inner side in the thickness direction of the first block 21 and the second block 22 (a pair of blocks). As shown in Figs. 2 and 3, the surface treatment section 51 is provided across the conveyance direction from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side).

[0041] 4, the surface treatment portion 51 includes an inner surface portion 51a and a side surface portion 51b. The inner surface portion 51a of the surface treatment portion 51 is provided on both widthwise end portions 35a, including the edges 36, of the inner surface 35 facing the liquid reservoir portion 23 of each of the blocks 21 and 22. The side surface portion 51b of the surface treatment portion 51 is provided on the thicknesswise inner end portion 37a, including the edges 36, of the side surface 37 on the outer side in the width direction of each of the blocks 21 and 22.

[0042] The surface treatment portion 51 is configured so that the contact angle with respect to the coating liquid C is different from that of the widthwise inner portion 35b of the surface treatment portion 51 on the inner surface 35 facing the liquid pool portion 23 of the first block 21 and the second block 22 (a pair of blocks). Note that the contact angle refers to the angle between the liquid surface and a solid wall surface when the free surface of a stationary liquid is in contact with the solid wall surface.

[0043] The surface treatment section 51 may be composed of a hydrophilic section that has been subjected to hydrophilic treatment. The hydrophilic section is suitable, for example, when the solvent of the coating liquid C is non-aqueous, such as N-methyl-2-pyrrolidone. A specific example of the hydrophilic section is glass coating. The contact angle between the surface that has been subjected to the hydrophilic treatment and the coating liquid C is preferably 0° or more and 50° or less, and more preferably 0° or more and 30° or less.

[0044] The surface treatment section 51 may be composed of a water-repellent section that has been subjected to a water-repellent treatment. The water-repellent section is suitable, for example, when the solvent of the coating liquid C is water-based, such as water or isopropyl alcohol. Specific examples of the water-repellent section include a fluorine coating and a ceramic coating. The contact angle between the surface that has been subjected to the water-repellent treatment and the coating liquid C is preferably 100° or more, and more preferably 120° or more.

[0045] (Coating mode) By driving the coating liquid supply pump 41, the coating liquid C passes through the coating liquid supply pipe 42 and the coating liquid supply path 32, and is supplied from the coating liquid supply port 30 to the liquid pool 23, where it is stored. With the coating liquid C stored in the liquid pool 23, the substrate 2 is passed through the liquid pool 23. As a result, the coating liquid C is applied to both sides of the substrate 2, and coating films F are formed on both sides of the substrate 2.

[0046] As shown in FIGS. 3 and 4, the widthwise middle portion 2b of the substrate 2 is a specific portion P to which the coating liquid C is applied. Meanwhile, each of the widthwise end portions 2a of the substrate 2 is a non-specific portion Q to which the coating liquid C is not applied. When the substrate 2 is passed through the liquid pool 23, each of the non-specific portions Q (each of the widthwise end portions 2a) of the substrate 2 is protruded from each of the exposure openings 29 to the outside of the liquid pool 23. As a result, the coating liquid C is applied to both sides of the specific portion P of the substrate 2, and a coating film F is formed on both sides of the specific portion P of the substrate 2. Meanwhile, since the coating liquid C is not applied to both sides of each of the non-specific portions Q of the substrate 2, no coating film F is formed.

[0047] When the substrate 2 is discharged from the liquid pool 23 through the substrate discharge outlet 25, a strong shear force is applied to the coating liquid C applied to both sides of the substrate 2 in the vicinity of the substrate discharge outlet 25. For this reason, as shown in Fig. 5, the thickness dimension T of the substrate 2 including the coating film F becomes slightly smaller than the gap dimension H of the substrate discharge outlet 25 (liquid pool 23).

[0048] The coating liquid C applied to the substrate 2 tends to spread outward in the width direction, but this outward spreading in the width direction is suppressed by the coating liquid suppression section 50 provided in the vicinity of the exposure opening 29 from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the conveying direction.

[0049] Specifically, the coating liquid suppression section 50 is composed of a surface treatment section 51. The surface treatment section 51 is provided in a portion including the edge 36 on the inner side in the thickness direction of each block 21, 22, i.e., in the vicinity of the exposed opening 29, and the contact angle with respect to the coating liquid C is different from that of the widthwise inner portion 35b of the surface treatment section 51 on the inner surface 35 of each block 21, 22. The coating liquid C applied to the substrate 2 is suppressed from spreading outward in the width direction by adjusting the contact angle (surface tension) in the surface treatment section 51 provided in the vicinity of the exposed opening 29.

[0050] (Action and effect) According to this embodiment, since the exposed opening 29 is provided on at least one side surface portion 26 in the width direction, a part of the substrate 2 in the width direction can be protruded from the exposed opening 29 to the outside of the liquid reservoir portion 23. This makes it possible to selectively form a coating film F on both sides of a specific portion P in the width direction of the substrate 2 being transported.

[0051] In particular, in this embodiment, the exposed openings 29 are provided on the first side portion 26a and the second side portion 26b on both sides in the width direction, so that when the width dimension B of the substrate 2 is larger than the width dimension L2 of each block 21, 22 (the width dimension of the liquid reservoir portion 23), both of the width direction end portions 2a of the substrate 2 can protrude from each exposed opening 29 to the outside of the liquid reservoir portion 23.

[0052] The coating liquid C applied to the substrate 2 tends to spread outward in the width direction, but this spread outward in the width direction is suppressed over the entire conveying direction by the coating liquid suppressing section 50 provided in the vicinity of the exposure port 29 from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the conveying direction. Specifically, the coating liquid C applied to the substrate 2 is suppressed from spreading outward in the width direction over the entire conveying direction by adjusting the contact angle (surface tension) in the surface treatment section 51 provided in the portion including the edge 36 on the inner side in the thickness direction of each of the blocks 21, 22.

[0053] This can reduce variation in the coating state at the widthwise end portion of the specific portion P of the substrate 2 (the boundary portion between the specific portion P and the non-specific portion Q, see FIG. 3).

[0054] Specifically, it is possible to prevent the coating liquid C applied to the substrate 2 from spilling out from the specific portion P side to the non-specific portion Q side at the widthwise end portion of the specific portion P (boundary portion between the specific portion P and non-specific portion Q, see FIG. 3). This makes it possible to reduce coating width variation of the coating film F finally formed on the substrate 2. In addition, it is possible to reduce coating position variation (waviness) in the transport direction of the coating film F finally formed on the substrate 2 at the widthwise end portion of the specific portion P of the substrate 2 (boundary portion between the specific portion P and non-specific portion Q, see FIG. 3).

[0055] In order to suppress the coating liquid C from spreading outward in the width direction, it is only necessary to adjust the contact angle (surface tension) by the surface treatment section 51, and therefore the configuration is simple.

[0056] Since the inner surface portion 51a of the surface treatment portion 51 is provided on both widthwise ends 35a of the inner surface 35 facing the liquid pool portion 23 of each of the blocks 21, 22, it is possible to prevent the coating liquid C in the liquid pool portion 23 from spreading outward in the width direction toward the exposed opening 29. In addition, since the side surface portion 51b of the surface treatment portion 51 is provided on the thicknesswise inner end portion 37a of the side surface 37 on the outer side in the width direction of each of the blocks 21, 22, it is possible to keep the coating liquid C leaking out of the liquid pool portion 23 via the exposed opening 29 (trying to spill out from the specific portion P side to the non-specific portion Q side).

[0057] The surface treatment section 51 (coating liquid suppression section 50) is provided near the exposed opening 29 on both sides in the width direction (the side of the first side surface section 26a and the side of the second side surface section 26b). This makes it possible to reduce variation in the coating state at both ends in the width direction of the specific portion P of the substrate 2 (at each of the boundaries between the specific portion P and two non-specific portions Q, see FIG. 3) when both ends 2a in the width direction of the substrate 2 are protruded from the respective exposed openings 29 to the outside of the liquid reservoir section 23.

[0058] <Second embodiment> A coating device 20 according to a second embodiment will be described with reference to Fig. 6. In the following description, the same components as those in the above embodiment are given the same reference numerals, and detailed description thereof may be omitted.

[0059] In this embodiment, one widthwise side 2c of the substrate 2 is a specific portion P. Meanwhile, the other widthwise side 2d of the substrate 2 is a non-specific portion Q. The other configurations are the same as those of the first embodiment.

[0060] <Third embodiment> A coating device 20 according to a third embodiment will be described with reference to Fig. 7. In the following description, the same components as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof may be omitted.

[0061] In this embodiment, the width dimension B of the substrate 2 is smaller than the width dimension L2 of each block 21, 22 (width dimension of the liquid reservoir 23). Moreover, the entire width of the substrate 2 is designated as a specific region P, and no non-specific region Q is provided. That is, the coating liquid C is applied to both sides of the substrate 2 in the entire width direction to form a coating film F (full coating). The other configurations are the same as those of the first embodiment.

[0062] <Fourth embodiment> A coating device 20 according to a fourth embodiment will be described with reference to Fig. 8. In the following description, the same components as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof may be omitted.

[0063] In this embodiment, the coating fluid suppression section 50 is composed of a throttle section 52. The throttle section 52 is provided near the exposed opening 29 in the width direction of the liquid pool section 23, i.e., at both width direction ends 23a. The throttle section 52 is provided from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the transport direction.

[0064] The constricted portion 52 is configured so that a gap dimension H between the first block 21 and the second block 22 (between a pair of blocks) is narrower than a widthwise inner portion 23b of the liquid pool 23 than the constricted portion 52. Specifically, the gap dimension H2 at the constricted portion 52 (both widthwise ends 23a) is narrower than the gap dimension H1 at the widthwise inner portion 23b of the constricted portion 52. The other configurations are similar to those of the first embodiment.

[0065] According to this embodiment, the coating liquid C applied to the substrate 2 is prevented from spreading outward in the width direction due to pressure loss at the throttle portion 52 provided in the vicinity of the exposed opening 29 in the liquid reservoir .

[0066] <Fifth embodiment> A coating device 20 according to a fifth embodiment will be described with reference to Fig. 9. In the following description, the same components as those in the above embodiment are given the same reference numerals, and detailed description thereof may be omitted.

[0067] In this embodiment, the narrowing portion 52 is configured in a tapered shape so that the gap dimension H2 between the first block 21 and the second block 22 (between a pair of blocks) narrows from the inner side in the width direction toward the exposed opening 29 side (from the inner side in the width direction to the outer side in the width direction).

[0068] The angle α between the throttle portion 52 and the inner surface 35 facing the liquid pool portion 23 of each block 21, 22 is greater than 0° and smaller than 90°. From the viewpoint of suppressing the outward spread of the coating liquid C in the width direction, it is preferable that the angle α is larger, and it is more preferable that the angle α is, for example, greater than or equal to 45° and less than or equal to 85°. The other configurations are the same as those of the fourth embodiment.

[0069] According to this embodiment, by finely adjusting the angle α of the constricted portion 52, it is possible to finely adjust the degree to which the coating liquid C is prevented from spreading outward in the width direction.

[0070] Sixth embodiment A coating device 20 according to a sixth embodiment will be described with reference to Fig. 10. In the following description, the same components as those in the above embodiment are given the same reference numerals, and detailed description thereof may be omitted.

[0071] In this embodiment, the coating liquid suppression section 50 is composed of grooves 53. The grooves 53 are provided near the exposed openings 29 of the inner surfaces 35 of the first block 21 and the second block 22 (a pair of blocks) that face the liquid pool 23, i.e., at both widthwise ends 35a. The grooves 53 extend from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the transport direction. The grooves 53 are configured to suck out the coating liquid C from the liquid pool 23 by capillary action. The other configurations are similar to those of the first embodiment.

[0072] According to this embodiment, the coating liquid C applied to the substrate 2 is sucked out from the liquid reservoir 23 by capillary action in the groove 53 provided in the vicinity of the exposed opening 29. This prevents the coating liquid C applied to the substrate 2 from spreading outward in the width direction.

[0073] <Seventh embodiment> A coating device 20 according to the seventh embodiment will be described with reference to Figures 11 and 12. In the following description, the same components as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof may be omitted.

[0074] In this embodiment, the coating fluid suppression section 50 is composed of a coating fluid suction section 54. The coating fluid suction section 54 sucks the coating fluid C in the fluid reservoir 23. The coating fluid suction section 54 includes a coating fluid suction port 54a, a coating fluid suction path 54b, a coating fluid suction pipe 54c, and a coating fluid suction pump 54d as a coating fluid suction device. The coating fluid suction port 54a is provided near the exposed opening 29 on the inner surface 35 of the first block 21 and the second block 22 (a pair of blocks) that faces the fluid reservoir 23, i.e., at both widthwise ends 35a. The coating fluid suction port 54a faces the fluid reservoir 23.

[0075] The coating liquid suction path 54b extends in the thickness direction inside each of the blocks 21 and 22. The coating liquid suction path 54b communicates with the coating liquid suction port 54a on its upstream side. A coating liquid suction pipe 54c is connected to the downstream side of the coating liquid suction path 54b. A coating liquid suction pump 54d is connected to the downstream side of the coating liquid suction pipe 54c.

[0076] The coating liquid suction pump 54d is provided outside the liquid reservoir 23 (each of the blocks 21, 22). The coating liquid suction pump 54d sucks the coating liquid C from the liquid reservoir 23 via the coating liquid suction port 54a, the coating liquid suction path 54b, and the coating liquid suction pipe 54c. For example, a diaphragm pump, a cylinder pump, or a mono pump may be used as the coating liquid suction pump 54d. The coating liquid suction pump 54d may be connected to or integrated with the coating liquid supply pump 41 (see FIG. 1) to circulate the coating liquid C.

[0077] In detail, the coating fluid suction section 54 includes a plurality of coating fluid suction ports 54a (coating fluid suction paths 54b). The plurality of coating fluid suction ports 54a are arranged along the transport direction from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side). The cross-sectional shape of the coating fluid suction ports 54a is, for example, circular or elliptical. The other configurations are similar to those of the first embodiment.

[0078] According to this embodiment, the coating liquid C to be applied to the substrate 2 is sucked from the liquid reservoir 23 by the coating liquid suction pump 54d through the coating liquid suction port 54a provided in the vicinity of the exposed opening 29. This prevents the coating liquid C to be applied to the substrate 2 from spreading outward in the width direction.

[0079] By arranging multiple coating liquid suction ports 54a along the transport direction, the coating liquid suction section 54 (coating liquid suppression section 50) can be easily arranged to extend from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the transport direction.

[0080] <Eighth embodiment> A coating device 20 according to an eighth embodiment will be described with reference to Figures 13 and 14. In the following description, the same components as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof may be omitted.

[0081] In this embodiment, the coating fluid suppression section 50 is configured with an air bumper 55 as a gas blowing section. The air bumper 55 is provided slightly outboard of the exposed openings 29 (each of the blocks 21, 22) in the width direction. The air bumper 55 is provided from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the conveying direction. Specifically, the gas passage 55a of the air bumper 55 extends from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the conveying direction.

[0082] The air bumper 55 is configured to blow gas from the outside in the width direction toward the exposed opening 29. Specifically, the air bumper 55 blows gas toward the base material 2 protruding from the exposed opening 29 to the outside of the liquid reservoir 23. The gas blown by the air bumper 55 is, for example, air, nitrogen, argon, or the like.

[0083] The angle β between the direction in which gas is blown by the air bumper 55 and the side surface portion 26 (thickness direction) is preferably 0° or more and 45° or less, and more preferably 0° or more and 30° or less. The other configurations are the same as those of the first embodiment.

[0084] According to this embodiment, gas is blown toward the exposed opening 29 from the outside in the width direction by the air bumper 55. Specifically, gas is blown toward the base material 2 protruding from the exposed opening 29 to the outside of the liquid pool 23 by the air bumper 55. As a result, the pressure of the coating liquid C on the outside of the exposed opening 29 in the width direction (outside the liquid pool 23) becomes greater than the pressure of the coating liquid C on the inside of the exposed opening 29 in the width direction (inside the liquid pool 23).

[0085] The coating liquid C applied to the substrate 2 tends to spread outward in the width direction, but this spread outward in the width direction is suppressed by the air bumper 55, which is provided on the widthwise outer side of the exposed opening 29, blowing gas onto the exposed opening 29.

[0086] <Ninth embodiment> A coating device 20 according to a ninth embodiment will be described with reference to Fig. 15. In the following description, the same components as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof may be omitted.

[0087] In this embodiment, the exposure opening 29 is provided only in the side surface portion 26 on one side in the width direction. Specifically, the exposure opening 29 is provided only in the second side surface portion 26b (one side surface portion in the width direction) on the other side in the width direction. In other words, the first side surface portion 26a (the side surface portion opposite to the above-mentioned one side) on one side in the width direction is closed. The first side surface portion 26a is configured by a side surface facing the liquid reservoir portion 23 in the side block 27 covering one side of the liquid reservoir portion 23 in the width direction.

[0088] A surface treatment portion 51 as a coating fluid suppression portion 50 is provided near the exposed opening 29 on the other widthwise side (the second side surface portion 26b side, one side in the widthwise direction). The other configurations are the same as those in the second embodiment.

[0089] According to this embodiment, the number of exposed openings 29 is only one, which is more advantageous than the above-described embodiment in terms of preventing the coating liquid C from leaking out of the liquid reservoir 23 via the exposed opening 29.

[0090] <Other embodiments> Although the present disclosure has been described above with reference to the preferred embodiments, such description is not limiting, and various modifications are possible.

[0091] In the first embodiment (particularly see FIG. 4), the surface treatment portion 51 may include either the inner surface portion 51a or the side surface portion 51b. In other words, the surface treatment portion 51 may include at least the inner edges 36 in the thickness direction of the first block 21 and the second block 22 (a pair of blocks).

[0092] In the first embodiment (see particularly Figure 4), the coating liquid suppression portion 50 may be configured as a contact angle changing portion, for example, so that its surface properties (surface roughness) are different from the surface properties (surface roughness) of the widthwise inner portion 35b of the inner surface 35 facing the liquid reservoir portion 23 of each block 21, 22.

[0093] In the second embodiment (see FIG. 6), the surface treatment section 51 (coating fluid suppressing section 50) is provided near the exposed opening 29 on both sides in the width direction (the first side surface section 26a side and the second side surface section 26b side), but is not limited to this. The surface treatment section 51 (coating fluid suppressing section 50) may be provided only near the exposed opening 29 on the second side surface section 26b side in the width direction (the side from which the substrate 2 protrudes). In other words, the surface treatment section 51 (coating fluid suppressing section 50) does not have to be provided near the exposed opening 29 on the first side surface section 26a side (the side from which the substrate 2 does not protrude).

[0094] In the seventh embodiment (see FIG. 12 in particular), the coating liquid suction ports 54a are arranged along the transport direction, but are not limited to this. The coating liquid suction ports 54a may be formed as elongated holes (slits) extending from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side) in the transport direction.

[0095] In the eighth embodiment (see particularly Figure 14), the gas spraying section 55 may be configured so that multiple nozzles are arranged along the conveying direction, widthwise outside of the exposed opening 29, from the substrate inlet 24 side (upstream side) to the substrate outlet 25 side (downstream side).

[0096] In the ninth embodiment (see FIG. 15), the first side surface portion 26a may face downward in the vertical direction, and the second side surface portion 26b (exposed opening 29) may face upward in the vertical direction. This makes it difficult for the coating liquid C in the liquid reservoir portion 23 to spread toward the exposed opening 29 (second side surface portion 26b) side on the upper side in the vertical direction due to gravity.

[0097] In the above embodiment, the conveying direction of the base material 2 is the horizontal direction, but is not limited to this. The base material 2 may be conveyed, for example, vertically from above to below, or vertically from below to above.

[0098] When it is desired to obtain the above-mentioned effect on only one of the two surfaces of the substrate 2, in the first to third embodiments (see Figures 1 to 7), the sixth embodiment (see Figure 10), the seventh embodiment (see Figures 11 and 12), the eighth embodiment (see Figures 13 and 14) and the ninth embodiment (see Figure 15), the coating liquid suppression section 50 (surface treatment section 51, groove section 53, coating liquid suction section 54, gas spraying section 55) need only be provided on one side in the thickness direction of the substrate 2.

[0099] In the above embodiment, the coating device 20 is used to apply the coating liquid C to both sides of the substrate 2 that is continuously transported by a roll-to-roll method, but is not limited thereto. The coating device 20 may be used, for example, to apply the coating liquid C to both sides of a glass substrate that is transported by a belt conveyor.

[0100] The coating method of the present disclosure uses a coating device 20 to pass the substrate 2 through the liquid pool 23 while a portion of the substrate 2 in the width direction protrudes from the exposed opening 29 to the outside of the liquid pool 23, thereby applying coating liquid C to both sides of a specific portion P in the width direction of the substrate 2, and suppressing the coating liquid C applied to the substrate 2 from spreading outward in the width direction in the vicinity of the exposed opening 29 by a coating liquid suppression section 50. EXAMPLES

[0101] <Setting conditions> (Example) The substrate 2 was made of SUS304 material having a thickness of 0.1 mm.

[0102] A conductive paste with a viscosity η of approximately 100 Pa·s was used as coating liquid C. The viscosity η of coating liquid C was measured using a rotational viscometer (Thermo Scientific Mars40, manufactured by HAAKE). The measurement conditions for viscosity η were as follows: stage diameter 20 mm, probe diameter 20 mm, angle 1°, measurement gap 0.05 mm, shear rate 1 / sec, and measurement temperature 25°C.

[0103] The coating device 20 according to the above embodiment having an arbitrary coating fluid suppression section 50 was used (however, not only the first block 21 but also the second block 22 was provided with a coating fluid supply port 30). Specifically, the coating device 20 was a tabletop coating device (Minilab, manufactured by Yasui Seiki). The first block 21 and the second block 22 were made of SUS304 material. The length dimension L1 of each block 21, 22 was 40 mm, the width dimension L2 was 50 mm, and the thickness dimension L3 was 10 mm. An arbitrary coating fluid suppression section 50 was provided near the exposure port 29 in the width direction, specifically, at a position 5 mm inside or outside from the width direction end of each block 21, 22.

[0104] Only the portion of the substrate 2 extending from the end in the width direction to a position 5 mm inward was passed through the liquid reservoir 23 .

[0105] A Mono Pump (3HMC010F, manufactured by Heishin Soubi) was used as the coating liquid supply pump 41. The unwinding torque and winding torque of the substrate supply device 10 were both 60 N·m. The coating speed (conveying speed) was 0.3 m per minute, and the substrate was conveyed horizontally so that the thickness direction of the substrate was oriented vertically.

[0106] The gap dimension H between the first block 21 and the second block 22 was set arbitrarily using a shim made of SUS304.

[0107] After the formation of the coating film F, it was dried for 30 minutes using a hot air drying oven (DKM-400, manufactured by Yamato Scientific) at a set temperature of 200° C. and a fan rotation speed of 500 rpm to obtain a dried film.

[0108] (Comparative Example) The coating device 20 used did not have the coating fluid suppression unit 50. The other conditions were the same as those in the example.

[0109] <Measurement conditions> The coating width (5 mm+α) of the coating film F formed on the substrate 2 was measured using an optical microscope (VHX-7000, manufactured by Keyence Corporation).

[0110] The average coating width was calculated from the measurements of five points at 5 mm intervals in the coating direction (transport direction). The standard deviation 3σ was calculated from the five measurements, and this was divided by the average coating width (expressed as a percentage).

[0111] <Measurement results> Example 1 The coating device (see Figs. 1 to 4) according to the first embodiment was used. The surface treatment (fluorine coating) 51 was applied to the portion including the edge 36 on the inner side in the thickness direction of each block 21, 22. In detail, the inner surface portion 51a of the surface treatment 51 was applied to the portion from the edge 36 to 5 mm inward in the width direction on the inner surface 35 facing the liquid reservoir 23 of each block 21, 22. The side surface portion 51b of the surface treatment 51 was applied to the portion from the edge 36 to 5 mm outward in the thickness direction on the outer side surface 37 of each block 21, 22 in the width direction. The gap dimension H was set to 0.2 mm. The average coating width was 5.5 mm, and the coating width variation was 10%, and good results were obtained.

[0112] Example 2 A coating device according to the fourth embodiment (see FIG. 8) was used. A constricted portion 52 was provided in a portion of the liquid reservoir 23 extending from the exposed opening 29 to 5 mm inward in the width direction. In detail, the gap dimension H2 in the constricted portion 52 was set to 0.1 mm. The gap dimension H1 of the portion 23b inward in the width direction from the constricted portion 52 in the liquid reservoir 23 was set to 0.2 mm. The average coating width was 5.4 mm, and the coating width variation was 8%, indicating good results.

[0113] Example 3 A coating device according to the sixth embodiment (see FIG. 10) was used. A groove 53 having a groove width of 1 mm was provided at a position 5 mm inward in the width direction from the exposed opening 29 on the inner surface 35 facing the liquid reservoir 23 of each block 21, 22. The gap dimension H was set to 0.2 mm. The average coating width was 5.5 mm, and the coating width variation was 10%, indicating good results.

[0114] Example 4 A coating device according to the seventh embodiment (see Figs. 11 and 12) was used. A coating liquid suction port 54a having a diameter of 1 mm was provided at a position 5 mm inward in the width direction from the exposed port 29 on the inner surface 35 facing the liquid reservoir 23 of each block 21, 22. A Mono Pump (3HMC010F, manufactured by Heishin Soubi) was used as the coating liquid suction pump 54d. The gap dimension H was set to 0.2 mm. The average coating width was 5.6 mm, and the coating width variation was 11%, indicating good results.

[0115] Example 5 A coating device according to the eighth embodiment (see Figs. 13 and 14) was used. An air bumper 55 was provided at a position 5 mm outward in the width direction from the exposed opening 29 (each block 21, 22). Air at a flow rate of 1 L / min was blown toward the exposed opening 29 from the outside in the width direction. The gap dimension H was set to 0.2 mm. The average coating width was 5.4 mm, and the coating width variation was 8%, indicating good results.

[0116] (Comparative Example) A coating device without a coating liquid suppression unit 50 was used. The other configurations were the same as in Example 1. The gap dimension H was 0.2 mm. The average coating width was 6.2 mm, and the coating width variation was 26%. [Industrial Applicability]

[0117] The present disclosure can be applied to a coating apparatus and a coating method, and is therefore extremely useful and has high industrial applicability. [Explanation of symbols]

[0118] X conveying direction Y Width direction Z thickness direction P Specific part Q Non-specific parts R region H Gap dimension H1 Gap dimension H2 Gap dimension C Coating liquid F Paint film 1 Coating system 2 Base material 20 Coating equipment 21 1st Block (Pair of Blocks) 22 2nd Block (Pair of Blocks) 23 Liquid reservoir (gap) 23b Widthwise inner part 24 Substrate inlet 25 Base material outlet 26 Side part 26a 1st side part 26b 2nd side part 29 Exposed mouth 35 Inside 35b Widthwise inner part 36 Edge 37 Side 50 Coating liquid suppression part 51 Surface treatment section (contact angle change section) 52 Squeezing section 53 Groove 54 Liquid suction section 54a Liquid suction port 54d Coating fluid suction pump (coating fluid suction device) 55 Air bumper (gas spraying part)

Claims

1. A coating device that applies a coating liquid to both sides of a sheet-like substrate being transported, A pair of blocks facing each other in a thickness direction of the base material; a liquid pool portion formed in a gap between the pair of blocks so that the coating liquid can be pooled and through which the substrate can pass, The liquid reservoir is a base material introduction port that opens to an upstream side in a conveying direction of the base material and through which the base material is introduced; a substrate discharge port that opens downstream in the conveying direction and through which the substrate is discharged; and side portions located on both sides in a width direction intersecting the conveying direction, An exposure opening is provided in at least one of the side surfaces in the width direction, the exposure opening extending from the base material inlet to the base material outlet, a portion of the base material in the width direction can protrude from the exposure opening to an outside of the liquid reservoir, a coating liquid suppressing portion that suppresses outward spreading of the coating liquid applied to the base material in the width direction is provided in the vicinity of the exposed opening in the width direction, The coating device, wherein the coating liquid suppression section is provided across the substrate inlet side and the substrate outlet side in the transport direction.

2. The coating device according to claim 1, the coating liquid suppressing portion is constituted by a contact angle changing portion provided in a portion including at least an edge of each of the pair of blocks on an inner side in the thickness direction, the contact angle change portion is configured so that a contact angle with respect to the coating liquid is different from a portion of an inner surface of the pair of blocks facing the liquid pool portion that is more inward in the width direction than the contact angle change portion.

3. The coating device according to claim 1, the coating liquid suppressing portion is formed of a throttle portion provided in the vicinity of the exposed opening of the liquid pool, The tapered portion is configured so that a gap dimension between the pair of blocks is narrower than a portion of the liquid pool that is more inward in the width direction than the tapered portion.

4. The coating apparatus according to claim 3, The narrowing portion is configured in a tapered shape such that a gap dimension between the pair of blocks narrows from the inner side toward the exposed opening side in the width direction.

5. The coating device according to claim 1, the coating liquid suppressing portion is formed of a groove portion provided near the exposed opening on an inner surface of each of the pair of blocks facing the coating liquid pool portion, The groove portion extends in the transport direction and is configured to suck the coating liquid out of the liquid pool portion by capillary action.

6. The coating device according to claim 1, the coating liquid suppressing section is configured with a coating liquid suction section that sucks the coating liquid in the liquid reservoir, The coating liquid suction unit is a coating liquid suction port provided near the exposed opening on an inner surface of each of the pair of blocks facing the liquid pool; a coating fluid suction device that is provided outside the fluid reservoir and that sucks the coating fluid from the fluid reservoir through the coating fluid suction port.

7. The coating device according to claim 6, a coating device, wherein a plurality of the coating liquid suction ports are arranged along the transport direction.

8. The coating device according to claim 1, the coating liquid suppression unit is composed of a gas blowing unit provided on the outer side of the exposed opening in the width direction, The gas blowing section is configured to blow gas toward the exposed opening from the outer side in the width direction.

9. In the coating device according to any one of claims 1 to 8, The exposure opening is provided in each of the side surface portions on both sides in the width direction, The coating device, wherein the coating liquid suppression units are provided in the vicinity of the exposed opening on both sides in the width direction.

10. In the coating device according to any one of claims 1 to 8, The exposure opening is provided only on one side surface portion in the width direction, The side portion opposite to the one side is closed, The coating device, wherein the coating liquid suppression section is provided in the vicinity of the exposed opening on one side in the width direction.

11. 11. A coating method using the coating device according to claim 1 , comprising: passing the substrate through a liquid pool while causing a portion of the substrate in the width direction to protrude from the exposed opening to the outside of the liquid pool, thereby applying the coating liquid to both surfaces of a specific portion of the substrate in the width direction, and suppressing, by the coating liquid suppressing unit, outward spreading of the coating liquid applied to the substrate in the width direction in the vicinity of the exposed opening in the width direction.

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