Slit die head and coating device equipped with slit die head

Abstract

Provided are a slit die head and a coating device which reduce thickness unevenness in a cross coating part extending in a crossing direction crossing a coating direction. This slit die head 20 for coating cross coating parts 71, 74 extending in a crossing direction B crossing a coating direction A by means of a coating liquid P discharged from a slit-like discharge port 24 comprises: a storage part 22 which is formed inside the slit die head 20 and stores the coating liquid P; and a roll 30 extending in the crossing direction B. The roll 30 includes: a trunk part 31 rotatably disposed in the storage part 22; an intersection groove 36 formed on a trunk surface 33 of the trunk part 31, extending in the intersection direction B, and having a shape corresponding to the cross coating parts 71, 74; an introduction port 34 which is formed on the trunk surface 33 and introduces the coating liquid P stored in the storage part 22; and a communication part 35 communicating the intersection groove 36 and the introduction port 34.

Description

Slit die head and coating device equipped with the slit die head

[0001] The present invention relates to a slit die head and a coating device equipped with the slit die head, and more particularly to a coating device for coating a so-called "frame-shaped" coating pattern surrounded by a rectangular peripheral portion.

[0002] The frame-shaped coating pattern has parallel coated portions extending parallel to the coating direction, cross coated portions extending in a direction intersecting the coating direction, and uncoated portions surrounded by the parallel coated portions and the cross coated portions. Patent Document 1, for example, discloses a conventional technique for applying a frame-shaped coating pattern by coating in a single stroke using a dispenser. Coating using a dispenser has the problem of thickening the coating thickness at the joint where the start and end points of the single stroke overlap, resulting in non-uniform film thickness.

[0003] Patent Document 2 discloses a coating nozzle in which a coating liquid containing recess of a predetermined shape is provided on the outer peripheral surface of a coating liquid supplier. Patent Document 3 discloses a coating device in which a coating liquid receiving portion including a grooved portion and a non-grooved portion is provided on the outer peripheral surface of a drum. That is, Patent Documents 2 and 3 disclose a slit die head having an internal roll engraved with grooves of a predetermined shape that temporarily store a coating liquid.

[0004] JP 2021-49500 A JP 2021-98154 A JP 2017-109151 A

[0005] When a frame-shaped coating pattern 70 was applied to a substrate using a slit die head having grooves on the outer peripheral surface of a roll, thickness unevenness in the cross direction occurred, where the central film thickness was thinner than the edge film thickness at the cross-coated areas 71, 74, as shown in the G-G cross section of Figure 18. This type of thickness unevenness was particularly noticeable when the width of the cross-coated areas 71, 74 was narrow, when coating was performed at high speed, or when the viscosity of the coating liquid was high.

[0006] The inventors have thoroughly investigated the above phenomenon and have found the following: Since the coating liquid is indirectly supplied to the cross grooves corresponding to the cross-coated sections 71 and 74 via the parallel grooves corresponding to the parallel-coated sections, the supply of coating liquid cannot keep up with the demand in the central sections of the cross-coated sections 71 and 74, causing thickness unevenness in the cross direction.

[0007] Therefore, an object of the present invention is to provide a slit die head and a coating device that reduce thickness unevenness in the cross direction in the cross-coated area.

[0008] In order to solve the above problems, a slit die head according to one embodiment of the present invention is a slit die head that coats a cross coating section extending in a cross direction intersecting a coating direction with a coating liquid discharged from a slit-shaped discharge port, and includes: a storage section formed inside the slit die head that stores the coating liquid; and a roll that extends in the cross direction, wherein the roll has: a body portion that is rotatably arranged within the storage section; a cross groove that is formed on the body surface of the body, extends in the cross direction, and has a shape that corresponds to the cross coating section; an inlet port that is formed on the body surface and introduces the coating liquid stored in the storage section; and a communication section that communicates the cross groove with the inlet.

[0009] According to this invention, the coating liquid stored in the storage section is supplied directly and smoothly to the intersecting grooves formed on the roll body surface through the communicating section, thereby reducing thickness unevenness in the intersecting direction in the intersecting coating section.

[0010] 1 is a diagram illustrating a coating apparatus including a slit die head according to embodiment 1. FIG. 1 is a diagram illustrating a roll in the slit die head shown in FIG. 1. FIG. 2 is a developed view of the body surface of the roll shown in FIG. 2. FIG. 3 is a schematic view of a side cross section of the central portion of the roll shown in FIG. 2. FIG. 4 is a diagram illustrating a shim plate in the slit die head shown in FIG. 1. FIG. 5 is an enlarged view of a main portion of the shim plate shown in FIG. 5. FIG. 6 is a view taken along arrows VII-VII of the shim plate shown in FIG. 6. FIG. 7 is a diagram illustrating coating of a cross-coated portion by the slit die head shown in FIG. 1. FIG. 8 is a diagram illustrating coating of a parallel-coated portion by the slit die head shown in FIG. 1. FIG. 9 is a diagram illustrating a square-shaped coating pattern. FIG. 10 is a cross-sectional view illustrating a slit die head according to embodiment 2. FIG. 11 is a developed view of the body surface of the roll in a slit die head according to embodiment 3. FIG. 12 is a schematic view of a side cross section of the central portion of the roll corresponding to FIG. 12. FIG. 13 is a developed view of the body surface of the roll in a slit die head according to embodiment 4. FIG. 14 is a schematic view of a side cross section of the central portion of the roll corresponding to FIG. 14. FIG. 15 is a developed view of the body surface of the roll in a slit die head according to embodiment 5. FIG. 22 is a diagram schematically showing a side cross section of the central part of a roll corresponding to FIG. 16. FIG. 23 is a diagram illustrating a coating pattern in the shape of a square in accordance with Modification 1. FIG. 24 is a diagram illustrating a coating pattern in the shape of a square in accordance with Modification 2. FIG. 25 is a diagram showing a developed view of the body surface of a roll in a slit die head corresponding to the coating pattern in the shape of a square in accordance with Modification 3. FIG. 26 is a bottom view of the slit die head shown in FIG. 21. FIG. 27 is a diagram schematically showing a coating device in accordance with Modification 4.

[0011] Hereinafter, an embodiment of a slit die head 20 and a coating device 1 according to the present invention will be described with reference to the drawings. In the following description, terms indicating specific directions or positions (e.g., terms including "upper," "lower," "right," "left," "front," and "rear") will be used as necessary. However, the use of these terms is intended to facilitate understanding of the present disclosure with reference to the drawings, and the meanings of these terms do not limit the technical scope of the present disclosure. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative positions, and the like of the components described in the following embodiments are not intended to limit the scope of the present invention to these alone.

[0012] [Overall Configuration of Coating Apparatus] Fig. 1 is a diagram illustrating a coating apparatus 1 including a slit die head 20 according to embodiment 1. The overall configuration of the coating apparatus 1 will be described with reference to Fig. 1. In Fig. 1, valves in an open state are indicated by white outlines, and valves in a closed state are indicated by black outlines.

[0013] As shown in FIG. 1 , the coating apparatus 1 includes a coating fluid supply device 3 and a slit die head 20. The coating fluid supply device 3 is connected to the slit die head 20 via a coating fluid piping 4. When the coating fluid stored in the storage section 22 decreases, the coating fluid supply valve 5 is opened to supply the coating fluid P stored in the coating fluid supply device 3 to the slit die head 20. At this time, the gas supply adjustment valve 14 is closed and the gas exhaust valve 15 is opened to exhaust air from the storage section 22. The coating fluid P is a general term for a liquid material with fluidity, such as a water-like liquid, a paste-like highly viscous liquid material, or a highly concentrated slurry material.

[0014] The slit die head 20 has a die 21, a roll 30, and a shim plate 40. The die 21 has a first die 21a and a second die 21b that can be divided into two along a cross direction B that intersects with the coating direction A. The shim plate 40 is configured to be sandwiched between the first die 21a and the second die 21b. The die 21 has a storage section 22 in its internal space, and the coating liquid P supplied from the coating liquid supply device 3 is stored in the storage section 22. The roll 30 is disposed in the storage section 22 so that the roll 30 is immersed in the coating liquid P stored in the storage section 22.

[0015] A gas pipe 12 is connected to the top of the die 21, and a gas supply adjustment valve 14 and a gas exhaust valve 15 are disposed on the gas pipe 12. When the gas supply adjustment valve 14 is opened and the coating solution supply valve 5 and the gas exhaust valve 15 are closed, pressurized air is supplied by the gas supply device 10. The coating solution P stored in the storage section 22 is pressurized by the pressurized air. The coating solution P filled in the coating groove is discharged from the slit-shaped discharge port 24 via a shim plate 40. At this time, the gas supply adjustment valve 14 is closed and the gas exhaust valve 15 is opened to discharge the air from the storage section 22.

[0016] [Embodiment 1] Next, a slit die head 20 according to embodiment 1 will be described with reference to Figures 2 to 4. Figure 2 is a diagram illustrating the roll 30 in the slit die head 20 shown in Figure 1. Figure 3 is a developed view of the barrel surface 33 of the roll 30 shown in Figure 2. Figure 4 is a diagram schematically illustrating a side cross section of the central portion of the roll 30 shown in Figure 2.

[0017] As shown in Figure 2, the roll 30 has, for example, a cylindrical body portion 31 and a shaft portion 32. The body portion 31 and the shaft portion 32 have a cylindrical or cylindrical shape and extend in a cross direction B that crosses the coating direction A. The cross direction B crosses, for example, perpendicularly to the coating direction A. The body portion 31 is in sliding contact with the bottom of the storage section 22. A shaft portion 32 extends from each of the left and right ends of the body portion 31. Each shaft portion 32 is rotatably supported by the left and right sides of the die 21.

[0018] As shown in Figures 2 to 4, a cross groove 36 and a pair of left and right parallel grooves 37, 37 are engraved to a predetermined depth on the barrel surface 33 of the barrel portion 31. The cross groove 36 has a generally rectangular shape extending a first cross length b1 in the cross direction B. For example, a protruding groove 39 is formed at the end of the cross groove 36. The protruding groove 39 has a curved inner periphery, as in the coating pattern 70 shown in Figure 10, and therefore has a shape that protrudes in an arc from the center to the end. The parallel groove 37 has a rectangular shape extending a first parallel length b2 in the cross direction B and in the coating direction A. The side edges of the cross groove 36 and the side edges of the pair of left and right parallel grooves 37, 37 are spaced a predetermined distance apart. This prevents unnecessary coating of the uncoated area 75 in the coating pattern 70 shown in Figure 10.

[0019] As shown in Figures 3 and 4, an inlet 34 is formed on the opposite side of the intersecting groove 36 at a position 180 degrees point-symmetrical. The inlet 34 has a rectangular shape corresponding to the intersecting groove 36. The body portion 31 has a communication portion 35 that extends linearly through the body portion 31 in the radial direction. This reduces pressure loss in the intersecting groove 36. The communication portion 35 has a rectangular shape corresponding to the inlet 34 and the intersecting groove 36. Therefore, the inlet 34 and the intersecting groove 36 are in communication with each other via the communication portion 35 formed inside the body portion 31.

[0020] Fig. 5 is a diagram illustrating the shim plate 40 in the slit die head 20 shown in Fig. 1. Fig. 6 is an enlarged view of a main portion of the shim plate 40 shown in Fig. 5. Fig. 7 is a view taken along the arrows VII-VII of the shim plate 40 shown in Fig. 6.

[0021] 5 , the shim plate 40 is a flow rectifying plate that has a plate-like body 41, intersecting groove flow paths 42, and parallel groove flow paths 44, and controls the flow of the coating liquid P in the intersecting direction B. The plate-like body 41 has a generally rectangular shape extending in the intersecting direction B. The shim plate 40 is disposed at the discharge port 24 formed on the downstream side of the die 21, and is sandwiched between the first die 21 a and the second die 21 b of the die 21.

[0022] As shown in Figures 6 and 7, a cross groove channel 42 and left and right parallel groove channel channels 44 are recessed into one surface of the plate-like body 41. A first cross groove opening 61 having a first cross length b1 corresponding to the cross groove 36 is formed on the upstream side of the cross groove channel 42. A second cross groove opening 63 having a second cross length B1 corresponding to the cross coating sections 71, 74 (shown in Figure 10) is formed on the downstream side of the cross groove channel 42. A first parallel groove opening 62 having a first parallel length b2 corresponding to the parallel groove 37 is formed on the upstream side of the parallel groove channel 44. A second parallel groove opening 64 having a second parallel length B2 corresponding to the parallel coating sections 72, 73 (shown in Figure 10) is formed on the downstream side of the parallel groove channel 44.

[0023] The intersecting groove channels 42 and the parallel groove channels 44 are separated by a partition wall 43. The partition wall 43 has a confluence restriction portion 48 on its downstream side. A confluence portion 45 is formed between the downstream end of the plate-like body 41 and the tip of the confluence restriction portion 48. At the confluence portion 45, the intersecting groove channels 42 and the parallel groove channels 44 are connected, so that the coating liquid P from the intersecting groove channels 42 and the coating liquid P from the parallel groove channels 44 merge. This allows the ends of the intersecting coated portions 71, 74 to be connected to the ends of the parallel coated portions 72, 73. The height of the confluence portion 45 is within 30% of the height of the shim plate 40. This ensures the confluence of the coating liquid P at the confluence portion 45 and prevents interference between the coating liquid P from the intersecting groove channels 42 and the coating liquid P from the parallel groove channels 44 before they reach the confluence portion 45.

[0024] A plurality of gap retaining portions 47 are formed in the intersecting groove flow passage 42, protruding in the thickness direction from the other surface side to one surface side of the plate-like body 41. This suppresses deformation of the shim plate 40 in the intersecting groove flow passage 42 when the shim plate 40 is clamped between the first die 21a and the second die 21b of the die 21, and ensures an appropriate coating width in the coating direction A of the intersecting coating portions 71, 74. The partition portions 43 and the gap retaining portions 47 are configured, for example, to be flush with one surface side of the plate-like body 41.

[0025] Figure 8 is a diagram illustrating coating of cross-coated sections 71 and 74 by the slit die head 20 shown in Figure 1. Figure 9 is a diagram illustrating coating of parallel-coated sections 72 and 73 by the slit die head 20 shown in Figure 1. Figure 10 is a diagram illustrating a frame-shaped coating pattern 70.

[0026] As shown in FIG. 10 , the coating pattern 70 applied to the surface of a substrate (not shown) has a frame shape defined by a front cross-coated section 71 and a rear cross-coated section 74 extending in the cross direction B, and a left parallel-coated section 72 and a right parallel-coated section 73 extending in the coating direction A. The front cross-coated section 71 and the rear cross-coated section 74 extend a second cross length B1 in the cross direction B. The left parallel-coated section 72 and the right parallel-coated section 73 extend a second parallel length B2 in the cross direction B. The coating pattern 70 has an uncoated section 75 in its inner portion. The uncoated section 75 is a portion to which the coating fluid P is not applied. The corners of the inner peripheral portion of the coating pattern 70 shown in FIG. 10 are rounded with R-surfaces corresponding to the protruding grooves 39 of the cross grooves 36. When the intersecting groove 36 has a simple rectangular shape, the corners of the inner peripheral portion of the coating pattern 70 have a sharp pin-angle shape (a corner that is not chamfered).

[0027] As shown in FIG. 8 , the barrel 31 of the roll 30 is disposed so as to be fully immersed in the coating liquid P stored in the storage section 22. When pressurized air is supplied, the coating liquid P stored in the storage section 22 is pressurized by the pressurized air. The pressurized coating liquid P is directly and smoothly supplied to the intersecting grooves 36 through the inlet 34 and the communicating section 35, filling the intersecting grooves 36. The coating liquid P filled in the intersecting grooves 36 is discharged from the slit-shaped discharge outlet 24 via the shim plate 40. As a result, the front intersecting coating section 71 (intersecting coating section) shown in FIG. 10 coats the surface of the substrate (not shown). The coating liquid P is replenished into the intersecting grooves 36 through the inlet 34 and the communicating section 35. At this time, the amount of coating liquid P stored in the storage section 22 is controlled so that the liquid level of the coating liquid P in the storage section 22 is positioned above the height of the roll 30.

[0028] As shown in Figure 8, when the body 31 is immersed in the coating liquid P, the coating liquid P around the pair of left and right parallel grooves 37 faces the pair of left and right parallel grooves 37. Therefore, the coating liquid P is easily and smoothly supplied to the pair of left and right parallel grooves 37. Then, as shown in Figure 9, by rotating the roll 30 and transporting the workpiece (not shown) in the coating direction A, approximately half of the left parallel coated portion 72 and the right parallel coated portion 73 (parallel coated portions) shown in Figure 10 are coated on the surface of the workpiece (not shown).

[0029] When the substrate (not shown) reaches a position halfway along the length of the left parallel coated section 72 and the right parallel coated section 73 (parallel coated sections), the roll 30 is rotated in the reverse direction and the substrate (not shown) is transported in coating direction A, thereby coating the surface of the substrate (not shown) with the left parallel coated section 72 and the right parallel coated section 73 (parallel coated sections) shown in FIG. 10 . The rotation of the roll 30 is controlled so that the substrate further rotates in the reverse direction to return to the state shown in FIG. 8 . This results in the substrate (not shown) being coated with the rear cross coated section 74 (cross coated section) of the coating pattern 70 shown in FIG. 10 . This series of operations completes the formation of the frame-shaped coating pattern 70 shown in FIG. 10 .

[0030] Therefore, the coating liquid P stored in the storage section 22 is supplied directly and smoothly to the intersecting groove 36 formed on the body surface 33 of the roll 30 through the communicating section 35, thereby reducing thickness unevenness in the intersecting coating sections 71, 74.

[0031] [Embodiment 2] A slit die head 20 according to embodiment 2 will be described with reference to Fig. 11. Fig. 11 is a cross-sectional view that schematically illustrates the slit die head 20 according to embodiment 2.

[0032] 11, a seal shim 50 is provided at the bottom of the storage section 22 of the slit die head 20. The following mainly describes the differences from the slit die head 20 according to the first embodiment.

[0033] The seal shim 50 has elasticity and is made of, for example, rubber or elastomer. The seal shim 50 has a seal portion 51 in its upstream portion. The upper surface of the seal portion 51 has a curved sliding surface 52. The radius of curvature of the sliding surface 52 is the same as or larger than the radius of curvature of the barrel portion 31 of the roll 30. The barrel surface 33 of the barrel portion 31 is configured to be in sliding contact with the sliding surface 52. The curved sliding surface 52 improves the tight sealing of the barrel portion 31 with the barrel surface 33. Therefore, the seal shim 50 has both a shim function and a sealing function, and therefore reliably prevents the coating liquid P from leaking out from anywhere other than the intersecting grooves 36 and the parallel grooves 37, suppresses deformation of the coating pattern 70, and prevents the coating liquid P from adhering to the non-coated portion 75.

[0034] [Embodiment 3] A slit die head 20 according to embodiment 3 will be described with reference to Figures 12 and 13. Figure 12 is a developed view of the barrel surface 33 of the roll 30 in the slit die head 20 according to embodiment 3. Figure 13 is a schematic view showing a side cross section of the central part of the roll 30 corresponding to Figure 12.

[0035] 12 and 13, the communication section 35 that connects the inlet 34 and the intersecting groove 36 is characterized by having a wide communication section 35g and a narrow communication section 35h. The following description will focus on the differences from the slit die head 20 according to the first embodiment.

[0036] The inlet 34 is configured to be wider than the intersecting groove 36 in the circumferential direction of the barrel 31. The wide communicating portion 35g is a rectangular through-hole having a width and length corresponding to the circumferential width and axial length of the inlet 34. The narrow communicating portion 35h is a rectangular through-hole having a width and length corresponding to the circumferential width and axial length of the intersecting groove 36. The boundary between the wide communicating portion 35g and the narrow communicating portion 35h is located closer to the narrow communicating portion 35h. The boundary has a stepped shape in which the width in the coating direction A changes abruptly, but may also have a shape in which the width in the coating direction A changes gradually.

[0037] When coating the narrow cross-coated sections 71, 74, the cross groove 36 is configured to be narrow. However, if the inlet 34 is also configured to be narrow, it becomes difficult to introduce the coating liquid P. Therefore, if the inlet 34 is configured to be wide, the pressure loss in the communicating section 35 is reduced, making it easier and smoother to supply the coating liquid P. Therefore, the inlet 34 is configured to be wider than the cross groove 36, and the wide communicating section 35g is configured to be wider than the narrow communicating section 35h. This allows the coating liquid P to be easily and smoothly supplied to the communicating section 35 even when coating the narrow cross-coated sections 71, 74. Furthermore, the longitudinal length (cross direction B) of the communicating section 35 may be configured to be longer than the longitudinal length (cross direction B) of the cross groove 36. This reduces the pressure loss in the communicating section 35, making it easier and smoother to supply the coating liquid P.

[0038] [Embodiment 4] A slit die head 20 according to embodiment 4 will be described with reference to Figures 14 and 15. Figure 14 is a developed view of the barrel surface 33 of the roll 30 in the slit die head 20 according to embodiment 4. Figure 15 is a schematic view of a side cross section of the central part of the roll 30 corresponding to Figure 14.

[0039] 14 and 15 , the first communicating portion 35a and the second communicating portion 35b intersect radially inside the body portion 31. The following mainly describes the differences from the slit die head 20 according to the first embodiment.

[0040] A first intersecting groove 36a and a pair of left and right first parallel grooves 37a, 37a, a second intersecting groove 36b and a pair of left and right second parallel grooves 37b, 37b are engraved to a predetermined depth on the barrel surface 33 of the barrel 31.

[0041] On the opposite side of the first engraving group and at a position 180 degrees point symmetrical, a second engraving group is formed, which includes a first inlet 34a and a pair of second parallel grooves 37b, 37b on the left and right, and a second intersecting groove 36b and a pair of second parallel grooves 37b, 37b on the left and right, engraved to a predetermined depth.

[0042] A first inlet 34a is disposed on the opposite side of the first intersecting groove 36a at a position 180 degrees symmetrical about the first intersecting groove 36a. The first inlet 34a and the first intersecting groove 36a have rectangular shapes of the same size and are connected by a first communicating portion 35a. Therefore, the first communicating portion 35a is a through hole that extends linearly in the radial direction through the body portion 31. A second inlet 34b is disposed on the opposite side of the second intersecting groove 36b at a position 180 degrees symmetrical about the second intersecting groove 36b. The second inlet 34b and the second intersecting groove 36b have rectangular shapes of the same size and are connected by a second communicating portion 35b. Therefore, the second communicating portion 35b is a through hole that extends linearly in the radial direction through the body portion 31. The first communicating portion 35a and the second communicating portion 35b intersect perpendicularly in the radial direction within the body portion 31. The first intersecting groove 36a and the first inlet 34a have complementary functions, and the second intersecting groove 36b and the second inlet 34b also have complementary functions.

[0043] With one rotation of the roll 30, two coating patterns 70 are formed on the surface of the substrate: a first coating pattern formed by the first intersecting groove 36a, the pair of left and right first parallel grooves 37a, 37a, and the second inlet 34b, and a second coating pattern formed by the first inlet 34a, the pair of left and right second parallel grooves 37b, 37b, and the second intersecting groove 36b. This eliminates the need to reverse the roll 30, simplifying the coating operation and making it possible to continuously and repeatedly coat the same coating pattern 70 on a long film as the substrate is being transported.

[0044] [Embodiment 5] A slit die head 20 according to embodiment 5 will be described with reference to Figures 16 and 17. Figure 16 is a developed view of the barrel surface 33 of the roll 30 in the slit die head 20 according to embodiment 5. Figure 17 is a schematic view showing a side cross section of the central part of the roll 30 corresponding to Figure 16.

[0045] 16 and 17 , the first communicating portion 35a and the second communicating portion 35b, which intersect in the radial direction inside the body portion 31, are characterized in that the side of the inlet 34 is wider than the side of the cross-coated portion 36. In a sense, the fifth embodiment corresponds to a combination of the third and fourth embodiments described above.

[0046] A first intersecting groove 36a and a pair of left and right first parallel grooves 37a, 37a, a second intersecting groove 36b and a pair of left and right second parallel grooves 37b, 37b are engraved to a predetermined depth on the barrel surface 33 of the barrel 31.

[0047] A first inlet 34a is disposed on the opposite side of the first intersecting groove 36a, at a position 180 degrees point-symmetrical. The first inlet 34a and the first intersecting groove 36a are rectangular and communicate with each other via a first communicating portion 35a. The first communicating portion 35a has a wide communicating portion 35g and a narrow communicating portion 35h, and is a through-hole that extends linearly radially through the body portion 31. The wide communicating portion 35g of the first communicating portion 35a is a rectangular through-hole whose width and length correspond to the circumferential width and axial length of the first inlet 34a. The narrow communicating portion 35h of the first communicating portion 35a is a rectangular through-hole whose width and length correspond to the circumferential width and axial length of the first intersecting groove 36a.

[0048] A second inlet 34b is disposed on the opposite side of the second intersecting groove 36b, at a position 180 degrees symmetrical about the second intersecting groove 36b. The second inlet 34b and the second intersecting groove 36b are rectangular and communicate with each other via a second communicating portion 35b. The second communicating portion 35b has a wide communicating portion 35g and a narrow communicating portion 35h, and is a through-hole that extends linearly radially through the body portion 31. The wide communicating portion 35g of the second communicating portion 35b is a rectangular through-hole whose width and length correspond to the circumferential width and axial length of the second inlet 34b. The narrow communicating portion 35h of the second communicating portion 35b is a rectangular through-hole whose width and length correspond to the circumferential width and axial length of the second intersecting groove 36b.

[0049] [Modification 1] A coating pattern 70 in the shape of a Japanese character 'day' according to Modification 1 will be described with reference to FIG.

[0050] 18 , the coating pattern 70 has a square-shaped configuration defined by a front cross-coated section 71, a middle cross-coated section 76, and a rear cross-coated section 74 extending in the cross direction B, and a left parallel-coated section 72 and a right parallel-coated section 73 extending in the coating direction A. The coating pattern 70 has two uncoated sections 75 in its inner portion.

[0051] The coating pattern 70 shown in Figure 18 is formed by a process in which the front cross coated section 71 is coated, approximately half of the left parallel coated section 72 and the right parallel coated section 73 are coated, the middle cross coated section 76 is coated, the remaining half of the left parallel coated section 72 and the right parallel coated section 73 are coated, and the rear cross coated section 74 is coated.

[0052] [Modification 2] A cross-shaped coating pattern 70 according to Modification 2 will be described with reference to Figs.

[0053] 19 , the coating pattern 70 has a square-shaped cross-coated portion defined by a front cross-coated portion 71, a middle cross-coated portion 76, and a rear cross-coated portion 74 extending in the cross direction B, and a left parallel-coated portion 72, a middle parallel-coated portion 77, and a right parallel-coated portion 73 extending in the coating direction A. The coating pattern 70 has four uncoated portions 75 in its inner portion.

[0054] The coating pattern 70 shown in Figure 19 is formed, for example, using a roll 30 in a slit die head 20 shown in Figure 20. An intersecting groove 36, a pair of left and right parallel grooves 37, 37, and an intermediate parallel groove 38 are engraved to a predetermined depth on the barrel surface 33 of the roll 30. An inlet 34 is disposed on the opposite side of the intersecting groove 36 at a position 180 degrees symmetrical about the point. The inlet 34 and the intersecting groove 36 have rectangular shapes of the same size and are communicated by a communicating portion 35. Therefore, the communicating portion 35 is a through-hole that extends linearly through the barrel portion 31 in the radial direction.

[0055] When the roll 30 rotates approximately halfway, half of the coating is performed by the intersecting groove 36, the pair of left and right parallel grooves 37, 37, the intermediate parallel groove 38, and the inlet 34, and when the roll 30 rotates in the opposite direction, the remaining coating is performed by the pair of left and right parallel grooves 37, 37 and the intersecting groove 36. This forms a cross-shaped coating pattern 70 as shown in Figure 19.

[0056] [Modification 3] A slit die head 20 according to Modification 3 will be described with reference to Figs. 21 and 22 .

[0057] 21 and 22 , the shim plate 40 of the slit die head 20 has a partition 46. The partition 46 has various shapes, such as a comb-tooth shape, a zigzag shape, or a wave shape, and extends along the intersecting direction B. The partition 46 has a function of separating the discharge port 24 into a plurality of discharge flow paths 49 in the intersecting direction B, thereby preventing interference between adjacent discharge flow paths 49.

[0058] [Modification 4] A coating device 1 according to Modification 4 will be described with reference to FIG.

[0059] As shown in Figure 23, the coating device 1 can also be applied to a roll-to-roll system in which continuous coating is performed by winding a roll-shaped substrate (not shown) such as paper, film, or foil around a back roll 7 and extruding the coating liquid P from the discharge port 24 of the slit die head 20.

[0060] Although specific embodiments of the present invention have been described, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention.

[0061] Although this does not limit the invention, for example, significant effects are achieved in the case of high-speed coating at a coating speed of 5 m / min or more, high-viscosity coating where the viscosity of the coating liquid P is 1000 cps or more, or narrow coating where the width of the cross-coated portions 71, 74 is 10 mm or less. Furthermore, even more significant effects are achieved when the width of the cross-coated portions 71, 74 is 3 mm to 5 mm.

[0062] In the above embodiment, a mode of coating a square-shaped coating pattern 70 having two intersecting coating sections 71, 74 and two parallel coating sections 72, 73 has been described, but the present invention can also be applied to a mode of coating a stripe-shaped coating pattern 70 in which multiple intersecting coating sections 71, 74 are arranged parallel to each other and spaced apart in the coating direction A.

[0063] In the above embodiment, the communicating portion 35 extends linearly in the radial direction inside the barrel portion 31 of the roll 30. However, the communicating portion 35 may be bent in a dogleg shape (e.g., at an obtuse angle) in the radial direction inside the barrel portion 31 of the roll 30 (e.g., at the axial center of the roll 30).

[0064] In the above embodiment, the roll 30 has two communicating portions 35a, 35b, and the two communicating portions 35a, 35b intersect at right angles at the axial center of the roll 30. However, the two communicating portions 35a, 35b may intersect at an acute angle at the axial center of the roll 30, or three or more communicating portions 35a, 35b may intersect at an acute angle at the axial center of the roll 30.

[0065] The present invention and its embodiments can be summarized as follows.

[0066] The slit die head (20) according to a first aspect of the present invention is a slit die head (20) that coats cross-coated sections (71, 74) extending in a cross direction (B) that intersects a coating direction (A) with a coating liquid (P) discharged from a slit-shaped discharge port (24), and includes: a storage section (22) formed inside the slit die head (20) that stores the coating liquid (P); and a roll (30) that extends in the cross direction (B), wherein the roll (30) has: a body section (31) that is rotatably disposed in the storage section (22); a cross groove (36) that is formed on a body surface (33) of the body section (31), extends in the cross direction (B), and has a shape that corresponds to the cross-coated sections (71, 74); an inlet (34) that is formed on the body surface (33) and introduces the coating liquid (P) stored in the storage section (22); and a communication section (35) that communicates between the cross groove (36) and the inlet (34).

[0067] According to the above-described embodiment, the coating liquid P stored in the storage section 22 is supplied directly and smoothly to the intersecting groove 36 formed on the body surface 33 of the roll 30 through the communicating section 35, thereby reducing thickness unevenness in the intersecting coating sections 71, 74.

[0068] In addition, in the slit die head 20 according to the second aspect, in the first aspect, the communication portion 35 is a through hole that extends linearly in the radial direction of the body portion 31.

[0069] According to the above aspect, the pressure loss in the intersecting groove 36 can be reduced.

[0070] In addition, the slit die head 20 according to a third aspect is the same as that of the first aspect, in which the roll 30 further includes parallel grooves 37 extending parallel to the coating direction A.

[0071] According to the above embodiment, a frame-shaped coating pattern 70 having two cross-coated portions 71, 74 and two parallel-coated portions 72, 73 can be applied.

[0072] In addition, the slit die head 20 according to the fourth aspect is the same as that of the third aspect, except that a shim plate 40 having a junction 45 connecting the spaced apart intersecting grooves 36 and parallel grooves 37 is disposed at the discharge outlet 24.

[0073] According to the above-described embodiment, the coating liquid P from the intersecting groove flow path 42 and the coating liquid P from the parallel groove flow path 44 join together, and the ends of the intersecting coated portions 71, 74 and the ends of the parallel coated portions 72, 73 can be connected.

[0074] Further, in the slit die head 20 according to a fifth aspect, in the fourth aspect, the height of the joining portion 45 is within 30% of the height of the shim plate 40 .

[0075] According to the above aspect, the confluence of the coating liquids P at the confluence portion 45 can be ensured, and interference between the coating liquid P from the intersecting groove flow path 42 and the coating liquid P from the parallel groove flow path 44 can be prevented.

[0076] In another aspect, the coating device 1 is characterized by including the slit die head 20 of any one of the first to fifth aspects.

[0077] According to the coating device 1, the coating liquid P stored in the storage section 22 is supplied directly and smoothly to the intersecting groove 36 formed on the body surface 33 of the roll 30 through the communicating section 35, thereby reducing thickness unevenness in the intersecting coating sections 71, 74.

[0078] DESCRIPTION OF SYMBOLS 1... Coating device 3... Coating liquid supply device 4... Coating liquid piping 5... Coating liquid supply valve 7... Back roll 10... Gas supply device 12... Gas piping 14... Gas supply adjustment valve 15... Gas discharge valve 20... Slit die head 21... Die 21a... First die 21b... Second die 22... Storage section 24... Discharge outlet 30... Roll 31... Body section 32... Shaft section 33... Body surface 34... Inlet 34a... First inlet 34b... Second inlet 35... Communicating section 35a... First communicating section 35b... Second communicating section 35g... Wide communicating section 35h... Narrow communicating section 36... Intersecting groove 36a... First intersecting groove 36b... Second intersecting groove 37... Parallel groove 37a... First parallel groove 37b...Second parallel groove 38...Intermediate parallel groove 39...Protruding groove 40...Shim plate 41...Plate-shaped body 42...Intersecting groove flow path 43...Partition wall portion 44...Parallel groove flow path 45...Merge portion 46...Partition portion 47...Gap retaining portion 48...Merge regulation portion 49...Discharge flow path 50...Seal shim 51...Seal portion 52...Sliding contact surface 61...First intersecting groove opening 62...First parallel groove opening 63...Second intersecting groove opening 64...Second parallel groove opening 70...Coating pattern 71...Front intersecting coated portion (intersecting coated portion) 72...Left parallel coated portion (parallel coated portion) 73...Right parallel coated portion (parallel coated portion) 74...Rear intersecting coated portion (intersecting coated portion) 75...Non-coated portion 76...Intermediate intersecting coated portion (intersecting coated portion) 77... Intermediate parallel coated portion (parallel coated portion) A... Coating direction B... Cross direction b1... First cross length B1... Second cross length b2... First parallel length B2... Second parallel length P... Coating liquid

Claims

1. A slit die head which coats a cross coating section extending in a cross direction intersecting a coating direction with a coating liquid discharged from a slit-shaped discharge port, comprising: a storage section formed inside the slit die head for storing the coating liquid; and a roll extending in the cross direction, wherein the roll has: a body section rotatably disposed within the storage section; a cross groove formed on a body surface of the body section, extending in the cross direction and having a shape corresponding to the cross coating section; an inlet section formed on the body surface for introducing the coating liquid stored in the storage section; and a communication section communicating between the cross groove and the inlet.

2. A slit die head as described in claim 1, characterized in that the communication portion is a through hole extending linearly in the radial direction of the body portion.

3. The slit die head according to claim 1, wherein the roll further comprises parallel grooves extending parallel to the coating direction.

4. A slit die head as described in claim 3, characterized in that a shim plate having a junction portion where the intersecting grooves and the parallel grooves, which are spaced apart, are joined, is disposed at the discharge port.

5. The slit die head according to claim 4, wherein the height of the junction is within 30% of the height of the shim plate.

6. A coating device comprising a slit die head according to any one of claims 1 to 5.

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