JP2008246280A - Slot die, apparatus for manufacturing base material having coating film, and method of manufacturing base material having coating film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a slot die capable of locally controlling the discharge quantity distribution precisely and rapidly in accordance with the thickness unevenness which changes locally and suddenly at the end part of the coating film in the formation of the coating film on a base material to be coated using the slot die, a method of manufacturing the base material having the coating film using the slot die and an apparatus for manufacturing the base material having the coating film. <P>SOLUTION: In the slot die, three of more slot regulating members having a liquid contact face with a coating liquid and regulating the shape of the slot are arranged in the coating width direction, a member connection means for connecting at least two slot regulating members adjacent in the coating width direction is provided and at least one of the three or more slot regulating members includes a discharge quantity control means for independently controlling the discharge quantity distribution of the coating liquid in a prescribed range of both end parts of the discharge port in the coating width direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a slot die used for forming a coating film on a substrate to be coated, and a coating liquid is coated on the substrate to be coated using this slot die to produce a substrate having a coating film. The present invention relates to a manufacturing method and a manufacturing apparatus.

  As a form of the base material on which the coating film is formed according to the present invention, there are a sheet form or a long sheet form. The single-wafer substrate manufactured by the present invention includes a color filter substrate and a TFT array substrate for a liquid crystal display, a back plate and a front plate for a plasma display, a semiconductor substrate, an optical filter, a printed substrate, an integrated circuit substrate, and the like. Can be mentioned. Examples of the long sheet-shaped substrate produced according to the present invention include a film, a metal sheet, a metal foil, and paper.

  The slot die is called a coating head, a die, a die, a slit die, or a slit nozzle. A coating apparatus using this slot die, a so-called die coater, discharges a coating liquid from a slit-shaped discharge port extending in the longitudinal direction of the slot die (hereinafter referred to as a coating width direction), and is spaced from the discharge port. As a coating apparatus for forming a coating film of a coating solution on the surface of a base material facing each other, it is widely used in various fields. In order to form a coating film, the slot die and the substrate are moved relative to each other, but the coating direction, which is the relative movement direction, and the coating width direction are substantially orthogonal to each other.

  Next, the application status of the die coater in a color liquid crystal display will be described. Manufacturing a color filter substrate or a TFT array substrate constituting a color liquid crystal display includes many steps of forming a coating film with a die coater. For example, a color filter has a coating formation process of a black matrix or RGB color pixel forming resist material, a surface flattening material, and a cell spacer holding photo spacer material, and a TFT is coated with a photoresist material or an organic insulating film material. There is a film formation process. In these coating film forming processes, combined with the recent demands for higher image quality, larger screens, and cost reduction, particularly in the coating width direction, a film thickness accuracy of ± 1% or less is required in the region excluding 10 mm from the substrate edge. . On the other hand, in order to improve productivity and reduce equipment costs, it is desirable to be able to share slot dies between processes and varieties.

  However, in this type of coating film forming process, even if a slot die having excellent discharge uniformity in the coating width direction is used, film thickness unevenness that fluctuates rapidly in a local range of the coating film end portion occurs. Therefore, it has been difficult to satisfy the above-described film thickness accuracy requirement. Furthermore, even if the same slot die is used, the film thickness unevenness that locally changes suddenly at the edge of the coating film is different in each process and product type. It is connected.

  The main cause of the nonuniformity of the film thickness that suddenly changes locally at the edge of the coating film is due to the low viscosity of several mPa · s discharged from the slot die outlet when the coating film is formed on the glass substrate. This is because the coating liquid having good fluidity forms a bead in the gap between the slot die and the glass substrate, and this bead flows along the coating width direction. For example, if the bead flows outward from the end of the discharge port in the application width direction, the coating width increases and the film thickness at the end of the paint film decreases sharply and becomes thinner, causing the bead to flow more inward. In this case, the coating width decreases and the film thickness at the coating film edge increases rapidly to increase the thickness. If such a bead flow occurs in the coating width direction, even if the coating liquid is uniformly discharged from the slot die, the film thickness unevenness at the coating film end portion becomes large, and the film thickness distribution is uniform. I can't get it. Also, the occurrence of film thickness unevenness that suddenly changes locally at the edge of the coating is different between each process and product type. Flow of beads in the application width direction formed in the gap between the slot die and the glass substrate In addition to the physical properties of the coating solution such as viscosity and surface tension, coating speed, coating thickness, gap amount between the slot die and the glass substrate, the surface state of the glass substrate, and the positional relationship between the glass substrate end and the discharge port end This is because it largely depends on the coating conditions. Furthermore, at the coating film edge where the film thickness unevenness becomes large, the flow of the coating liquid also occurs due to the solid content unevenness of the coating liquid generated during drying, and a uniform film thickness distribution in the liquid film immediately after coating is obtained. There is also a problem that it is difficult to maintain the coating film after drying.

  In this way, at the coating film edge, various factors act on each other and in a complex manner, resulting in uneven film thickness that changes locally. Therefore, in order to satisfy the required film thickness accuracy as described above regardless of each process and product type, even if there is a film thickness unevenness that locally changes suddenly at the edge of the coating film after drying, this film thickness unevenness occurs. The slot die is required to adjust the discharge amount distribution precisely and promptly only within the range, so that the film thickness distribution at the coating film end is uniform.

  As a known slot die that can actually adjust the discharge amount distribution, there are a groove formed by cutting out a part of the cross section of the slot die along the entire length in the coating width direction, and a neck whose thickness is reduced by this groove. In some cases, there is provided a discharge amount adjusting means including a plurality of differential screws arranged over the entire length in the coating width direction in order to elastically deform the neck portion (flexible portion) (for example, Reference 1). . In this discharge amount adjusting means, when the differential screw at an arbitrary position is moved to elastically deform the neck portion in the vicinity thereof, the gap amount between the slot and the discharge port at the corresponding position changes, and the gap amount changes. The discharge amount distribution is adjusted within the range. Since this slot die can be adjusted in the discharge amount distribution while mounted on the coater, the film thickness distribution can be adjusted quickly, while the neck portion is elastically deformed only gently along the coating width direction. If there is a film thickness unevenness that locally changes suddenly at the film end, the local discharge amount distribution cannot be adjusted accordingly. Furthermore, in a slot die having a structure in which a spacer is formed by sandwiching a spacer between lips, this spacer limits the gap adjustment range of the slot at the discharge port end in the coating width direction, and the discharge amount at the coating film end. There was also a problem that the distribution could not be adjusted locally.

  In order to make up for the drawbacks of these known means, there is a technique that adjusts the local discharge amount distribution at the coating film end using a spacer. These include a spacer shape defined so that the slot width defined by the spacers at both ends in the application width direction of the slot (the length of the application width direction of the slot) gradually changes along the discharge direction of the application liquid. Some spacer thicknesses are determined so that the gap amount between the slots at both ends in the coating width direction is locally changed (for example, Patent Documents 2, 3, and 4).

However, in order to adjust the discharge amount distribution at the coating film end with this configuration, it is necessary to replace the shim by detaching the slot die from the coater and disassembling and reassembling the slot die. Furthermore, this series of operations must be repeated until the film thickness distribution at the coating film end becomes uniform, and only the local discharge amount distribution at the coating film edge is precisely and quickly adjusted and corrected. It was not the structure which can obtain uniform film thickness distribution.
JP-A-9-131561 (6th column 7th line to 7th column 24th line, 9th column 14th line to 38th line, FIG. 3) JP-A-10-277464 (second column, line 48 to third column, line 43, FIGS. 5 and 7) JP 2001-29860 A (column 4, line 25 to column 8, line 28, FIGS. 2 and 4) Japanese Patent Laying-Open No. 2004-283379 (FIGS. 5 and 8)

  The object of the present invention is to focus on the above-mentioned problems, and to precisely and quickly adjust the discharge amount distribution locally in response to the film thickness unevenness that changes locally at the edge of the coating film. An object of the present invention is to provide a die and a method for producing a substrate having a coating film using the slot die, and a production apparatus. The substrate having a coating film produced according to the present invention is preferably used as a display member.

The above object is achieved by the means described below.
A coating liquid supply port for supplying the coating liquid to the slot die, a manifold for guiding the coating liquid supplied from the coating liquid supply port in the coating width direction, and a slit-like discharge extending in the coating width direction for discharging the coating liquid In a slot die having an outlet, a slot communicating the manifold and the discharge port,
(1) Three or more slot defining members having a liquid contact surface with the coating liquid and defining the shape of the slot are arranged in the coating width direction;
(2) A member coupling means for coupling at least two slot defining members adjacent to each other in the coating width direction is provided,
(3) At least one of the three or more slot defining members has a discharge amount adjusting means capable of independently adjusting the discharge amount distribution of the coating liquid in a predetermined range at both ends of the discharge port in the coating width direction.
It is characterized by that.

  In the slot die according to the present invention, at least one of a pair of liquid contact surfaces along the coating width direction of the slot is formed by the three or more slot defining members, of the slot defining members. The slot defining members disposed at both ends of the application width direction are members that form a liquid contact surface at both ends of the application width direction of the slot, and the discharge amount adjusting means adjusts the gap amount of the slot. The slot die including the discharge port is further provided with limiting means for limiting the positions of both ends of the coating liquid discharged from the discharge port in the coating width direction. Are preferred.

  An apparatus for producing a substrate having a coating film according to the present invention includes a slot die according to any one of claims 1 to 5, a pipe joined to the coating liquid supply port of the slot die, and the pipe. A coating liquid supply means for supplying the coating liquid to the coating liquid supply port, and a movement for moving at least one of the substrate to be coated and the slot die positioned at a distance from the discharge port of the slot die. And means.

  A method for producing a substrate having a coating film according to the present invention uses a slot die according to any one of claims 1 to 5, and discharges a coating liquid from a discharge port of the slot die and discharges the slot die. At least one of the substrate to be coated and the slot die located at a distance from the outlet is moved relatively to apply the coating liquid discharged from the discharge port onto the substrate to be coated. A film is formed on a substrate to be coated.

  When the slot die according to the present invention is used, the discharge amount distribution of the coating liquid can be independently and precisely adjusted locally within a predetermined range at both ends of the discharge port. Further, in this adjustment process, it is not necessary to detach the slot die from the applicator or disassemble and reassemble it. As a result, even if there is unevenness in the film thickness that suddenly changes locally at the edge of the coating, the slot die discharge amount distribution can be locally adjusted and corrected in response to this unevenness. A uniform film thickness distribution can be obtained over the entire width in the width direction.

    According to the method for producing a substrate having a coating film according to the present invention, since the substrate having a coating film is produced using the excellent slot die, the film thickness distribution is uniform over the entire width in the coating width direction. A substrate having a coating film can be produced with high productivity.

Hereinafter, examples of the best mode of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a slot die 1 according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view showing the slot die 1.
FIG. 3 is a cross-sectional view of the slot die 1 after assembly.
FIG. 4 is an enlarged front view of a part of the inner surface of the slot die 1.
FIG. 5 is an exploded perspective view showing a slot die 30 according to another embodiment of the present invention.
FIG. 6 is an exploded perspective view showing a slot die 40 which is still another embodiment of the present invention.
FIG. 7 is a schematic configuration diagram showing an example of a coating apparatus (die coater) equipped with the slot die of the present invention.

  As shown in FIG. 1, the slot die 1 of the present invention includes a first lip 2 and a second lip 3 collectively referred to as a so-called “lip”, and between the first lip 2 and the second lip 3. It consists of two sealing plates 12 sandwiched at both ends in the longitudinal direction. The first lip 2 and the second lip 3 are integrated by six assembly bolts 7 that are lip fastening elements after the inner surfaces, which are the surfaces sandwiching the seal plate 12, face each other. The first lip 2 includes a first member 4, a second member 5, and a third member 6 arranged along the longitudinal direction, that is, the coating width direction. Between these three first member 4, second member 5, third member 6 and second lip 3, a slit-like discharge port 10 for discharging the coating liquid extends in the coating width direction. Exist. The length of the discharge port 10 in the application width direction, that is, the discharge width Wd is defined by the interval in the application width direction between the two seal plates 12. The first lip 2, that is, the first member 4, the second member 5, the third member 6, and the second lip 3 include a discharge port 10 in the plane, A lip tip surface 14 is formed.

  Referring to FIG. 2, the first member 4, the second member 5, and the third member 6 are brought into close contact with each other in the coating width direction so that the inner surfaces 28A, B, and C are included in the same surface. After that, they are connected by a connecting bolt 8 which is a member connecting means. After the first member 4, the second member 5, and the third member 6 are combined, the first lip 2 functions as one member. The coupling surfaces 165, 166, and 167 for bringing the first member 4, the second member 5, and the third member 6 into close contact with each other in the coating width direction are known so that the coating liquid does not leak from the inside. It is finished with precision by grinding. Further, when the first member 4, the second member 5, and the third member 6 are coupled, in order to easily include the inner surfaces 28 </ b> A, B, and C in the same surface, The external shapes of the first member 4, the second member 5, and the third member 6 excluding the coupling surfaces 165, 166, and 167 are simultaneously processed, that is, the first member 4, the second member 5, and the third member. It is preferable that the outer shape is processed after being integrated in close contact with the coating width direction and finished to the same shape.

  In the first lip 2, steps of depth H extend over the entire length in the coating width direction on the inner surface 28A of the first member 4, the inner surface 28B of the second member 5, and the inner surface 28C of the third member 6. To do. Thus, as shown in FIG. 2, when the first lip 2 and the second lip 3 are combined and fastened together with the assembly bolt 7, the slot 9 having the gap Ls shown in FIG. Are formed along the coating width direction by the slot liquid contact surfaces 25A, B, C (only 25A in the drawing) of the lip 2 and the slot liquid contact surface 25D of the second lip 3. Here, the gap amount Ls of the slot 9 is an interval between the pair of slot liquid contact surfaces 25A, B, C and the slot liquid contact surface 25D in the application direction orthogonal to the application width direction. As shown in FIG. 3, the slot 9 communicates with the manifold 11 provided on the inner surface 29 of the second lip 3 and the discharge port 10. Further, the gap amount Ls of the slot 9 becomes equal to the depth H of the step provided on the inner surface of the second lip 2.

  Referring to FIG. 2 again, the two seal plates 12 are connected to the slot wetted surfaces 25A of the first member 4 and the third member 6 before the first lip 2 and the second lip 3 are integrated. , C are fixed to both outer ends in the coating width direction by bolts (not shown). For this reason, the above-mentioned discharge width Wd determined by the interval between the two seal plates 12 is also the length in the application width direction of the slot 9 where both ends in the application width direction are sealed. In the present embodiment, the first member 4, the second member 5, the third member 6, the second lip 3, and the two seal plates 12 are the slot defining members. That is, the slot defining member is a member that has a liquid contact surface with the coating liquid and forms the outer edge of the space that becomes the slot. The first member 4, the second member 5, and the third member 6 have a liquid contact surface with the coating liquid, and three or more are arranged in the coating width direction in order to define the shape of the slot 9. Slot defining member.

  On the other hand, the manifold 11 is formed on the inner surface 29 of the second lip 3 in the coating width direction. A coating liquid supply port 15 is provided in the central portion of the manifold 11 in the coating width direction. The coating liquid supply port 15 is connected to a pipe (not shown), and is connected to a coating liquid supply means (not shown) provided outside the slot die 1 through this pipe. The coating liquid supplied by the coating liquid supply means and flowing into the manifold 11 from the coating liquid supply port 15 is guided to both sides in the coating width direction around the coating liquid supply port 15 by the manifold 11 and then to the slot 9. It flows in and is uniformly discharged from the discharge port 10.

  In order to adjust the discharge amount distribution at both ends in the application width direction of the coating liquid discharged from the discharge port 10, discharge amount adjustment ranges W5 and W6 at both ends in the application width direction of the first lip 2 in FIG. Is provided with a discharge amount adjusting means comprising a groove 16, a differential screw 17 and a neck portion 23 shown in FIG. The discharge amount adjusting means can adjust the discharge amount distribution of the coating liquid over a predetermined range, that is, the discharge amount adjustment ranges W5 and W6.

  As shown in detail in FIG. 3, the differential screw 17 includes a lead screw 18, a slave screw 19, and a nut 20. The lead screw 18 is screwed at a screw pitch P1 into a female screw passing through the groove upper portion 21 in the vertical direction. The female screw 19 is screwed into the parent screw 18 at a screw pitch P2 smaller than the screw pitch P1, and is fixed by sandwiching the groove lower portion 22 with the nut 20. The neck portion 23 is a flexible portion formed by reducing the thickness of a part of the first lip 2 by the groove 16. When the lead screw 18 is turned here, the slave screw 19 relatively advances and retreats in the vertical direction by the difference between the screw pitches P1 and P2 according to the rotation angle. And the neck part 23 which is a flexible part elastically deforms according to this relative advance / retreat amount. When the neck portion 23 is elastically deformed and the groove lower portion 22 moves by La in the vertical direction (coating liquid discharge direction) at the position of the common center line of the lead screw 18 and the child screw 19, the lip tip portion 160 becomes the discharge port 10. Is moved by ΔLsm = La × LS1 / LS2 in the application direction (the direction indicated by the arrow in FIG. 3). As a result, the gap amount Ls of the slot 9 continuously changes in a section from the position S (shown by a one-dot chain line) having the smallest thickness at the neck portion 23 to the discharge port 10, and the gap change amount. ΔLs is expressed by ΔLs = ΔLsm × Lx / LS1, and the opening degree of the discharge port 10 is adjusted. Due to the change in the gap amount of the slot 9 that is the maximum value at the position of the discharge port 10, the pressure loss of the coating liquid flowing through the slot 9 changes, and the discharge amount of the coating liquid from the discharge port 10 increases or decreases. Distribution is adjusted. Here, LS1 is the length in the vertical direction (coating liquid discharge direction) from the position S to the discharge port 10, LS2 is the length from the slot liquid contact surface 25A to the common center line of the lead screw 18 and the lead screw 19, and Lx is the position. It is the length in the vertical direction from S to an arbitrary position. Here, in the slot die 1 of the present invention, the relative change amount of the slave screw 19 of the differential screw 17, that is, the gap change amount ΔLs changes minutely compared to the rotation angle of the lead screw 18, and the discharge amount distribution is precise. The neck portion 23 is provided in the middle of the upper edge 162 of the slot 9 and the outlet 10 so as to be as close to the outlet 10 as possible (LS1 is made as small as possible), and the differential screw 17 is attached to the slot wetted surface. It is arranged at a position as far as possible from 25A (LS2 is made as large as possible). With the above discharge amount adjusting means, the differential screw 17 that determines the adjustment pitch of the discharge amount distribution is one for each of the first member 4 and the third member 6, as shown in FIG. There are four in total, one on each side. The number and interval of the differential screws 17 are not particularly limited, and can be appropriately determined according to the discharge amount distribution adjustment pitch.

  Referring again to FIG. 2, the connecting bolt 8 that is a member connecting means is on the upper side of the neck portion 23 (on the opposite side to the discharge port 10) at the connecting surfaces 166 at both ends of the application width direction of the second member 5. The first member 4, the second member 5, and the third member 6 are joined to each other by being screwed into a female screw provided in the groove upper portion 21. The discharge amount adjusting means is provided independently for each of the first member 4, the second member 5, and the third member 6, and operates the differential screw 17 according to the fastening position of the coupling bolt 8. The movement of the groove lower part 22 and the elastic deformation of the neck part 23 are performed independently and freely without interference between adjacent members. Therefore, the adjustment of the discharge amount distribution of the coating liquid in the first member 4, the second member 5, and the third member 6 is performed without interfering with each other, the first member 4, the second member 5, and the third member. Each of the members 6 can be performed independently. In the second member 5, the discharge amount adjusting means is at both ends in the application width direction, and the groove 16 and the neck portion 23 constituting the discharge amount adjusting means are not present at the center in the application width direction. The discharge amount distribution adjustment by the differential screw 17 of the provided discharge amount adjusting means can be performed independently without interfering with each other at both ends, and does not affect the discharge amount distribution at the central portion in the coating width direction. Therefore, the discharge amount adjusting means provided in the first member 4, the second member 5, and the third member 6 interfere with each other in each of the adjustment division ranges W1, W2, W3, and W4. It is possible to freely adjust the discharge amount distribution independently without any problem. As described above, the slot die 1 of this embodiment can adjust the discharge amount distribution only in the discharge amount adjustment ranges W5 and W6 shown in FIG. Since the slot die 1 has the above-described configuration, a local sudden change in the discharge amount distribution such as increasing only the discharge amount in the adjustment division range W1 and decreasing only the discharge amount in the adjacent adjustment division range W2 is also possible. Can be freely adjusted. Therefore, in the slot die 1 of this embodiment, the distribution of the discharge amount distribution is adjusted accurately and promptly in response to the film thickness unevenness that locally changes suddenly at both ends of the coating film. It is possible to obtain

  Here, the lengths of the adjustment division ranges W1 to W4 and the discharge amount adjustment ranges W5 and W6 are appropriately determined according to the film thickness distribution situation of the coating film end determined by the physical properties of the coating liquid and the coating / drying conditions. There are no particular restrictions. For example, when a coating solution having a viscosity of 10 mPa · s or less is applied, film thickness unevenness that varies greatly often occurs only within a range from 50 mm to 100 mm from the end of the coating film, so the discharge amount adjustment ranges W5 and W6 Is preferably 50 mm or more and 100 mm or less. In many cases, the maximum film thickness unevenness occurs in the range from the coating film edge to 30 mm, and accordingly, the adjustment division ranges W1 and W4 are preferably set to 30 mm or less. As described above, it is preferable to divide the adjustment range for each unevenness of the film thickness so that the discharge amount distribution can be adjusted independently, because the adjustment work is facilitated.

  When a very high-quality coating film formation is required, the second lip 3 made of a single member is formed on the side on which the coating film is formed, the first lip with respect to the direction in which the coating film is formed. 2 on the opposite side, there is no concern that minute vertical stripes will occur at each connecting position of the first member 4, the second member 5, and the third member 6 which are slot defining members, preferable.

  Further, in the case where the coating liquid is applied to the substrate to be coated having a width wider than the discharge width Wd, as a limiting means for limiting the both end positions in the application width direction of the coating liquid discharged from the discharge port 10, FIG. It is preferable to provide the inclined surface 24 as shown in FIG. 8 at both ends of the lip tip surfaces 13 and 14 in the coating width direction. FIG. 4 is an enlarged front view of the application width direction end portion of the second lip 3 including the inclined surface 24, and the inclined surface 24 is spaced from the discharge port end 27 serving as the application width direction end portion of the discharge port 10. From the starting point 26 separated by A to the outside in the coating width direction, the coating liquid is formed at an inclination angle α and an inclination depth B in the direction opposite to the direction of discharge of the coating liquid. The coating liquid discharged from the discharge port 10 forms a bead (liquid pool) in the gap between the lip tip surfaces 13 and 14 and the substrate to be coated. The bead of this coating liquid is the discharge port end 27 of the discharge port 10. Can be prevented by the starting point 26 of the inclined surface 24 from flowing toward the outside in the coating width direction. As a result, both end positions of the coating liquid discharged from the discharge port 10 in the application width direction are restricted and fixed. If the discharge amount distribution is adjusted in such a manner that the both ends of the coating liquid in the coating width direction are fixed in this way, it is reliably reflected in the film thickness distribution at the coating film end, and the discharge amount distribution and the film thickness distribution are a pair. Since it corresponds to 1, adjustment becomes easy. The position and shape of the inclined surface 24, that is, the size of the distance A, the inclination angle α, and the inclination depth B are not particularly limited, and can be appropriately determined according to the application liquid and application conditions. For example, when a coating solution having a viscosity of 10 mPa · s or less is applied, the distance A is preferably 0.5 mm or less, and more preferably, in order to prevent the beads from flowing in the coating solution and fix both ends in the coating width direction. The inclination angle α is preferably 20 ° or more, more preferably 30 ° or more, and the inclination depth B is preferably 0.15 mm or more, more preferably 0.2 mm or more. Note that when the discharge width Wd is equal to the substrate width to be coated, the flow of the beads in the coating width direction is prevented at the side end of the substrate to be coated. It is not necessary to provide a restricting means for both positions in the coating width direction of the coating liquid.

  According to the slot die 1 shown in this embodiment, since it has the above-described configuration, the discharge amount adjusting means provided in a predetermined range (discharge amount adjustment ranges W5 and W6) at both ends of the discharge port is provided. The slots can be operated independently without interfering with each other in the adjustment division ranges W1 to W4 of the slot defining member that forms the slot along the coating width direction. As a result, the discharge amount distribution of the coating liquid can be precisely adjusted locally at both ends of the discharge port. That is, if the slot die 1 is used, even if there is a film thickness unevenness that locally changes suddenly at the end of the coating film, the discharge amount distribution is adjusted accurately and quickly in response to this, and the film thickness distribution Can be made uniform.

  In particular, displays such as color filters for color liquid crystal displays and array substrates for TFTs, which are required to achieve a uniform film thickness distribution over the entire width of the substrate to be coated, regardless of the type of coating liquid and coating / drying conditions. The slot die 1 can be suitably applied when manufacturing the member for use. When performing the above adjustment work, it is not necessary to remove the slot die 1 from the die coater and disassemble / reassemble / reinstall it, so that the film thickness distribution can be made uniform in a short time and the die coater can be operated. The rate can be increased and productivity can be improved.

  In the configuration of the slot die 1 shown in the above embodiment, the number of adjustment division ranges in the discharge amount adjustment ranges W5 and W6 is not limited to four (two on one side), but the first member 4 It is also possible to increase the number of adjustment division ranges by providing a slot defining member having more discharge amount adjusting means between the first member 5 and the second member 5 or between the second member 5 and the third member 6. It is. Further, the arrangement configuration of the slot defining members is not limited to the configuration of the slot die 1 shown in the above embodiment. Next, the slot die 30 having an arrangement configuration of slot defining members other than the above embodiment will be described.

  FIG. 5 shows a slot die 30 which is another embodiment of the present invention. In FIG. 5, the slot die 30 includes a first lip 31 and a second lip 32 that are collectively referred to as a “lip”, and two side plates 33. The first lip 31 and the second lip 32 are integrated by four assembly bolts 7 which are lip fastening means with their inner surfaces 37 and 38 facing each other. The two side plates 33 are respectively attached to both end faces 36 of the integrated first lip 31 and second lip 32 in the coating width direction by two coupling bolts 35 on one side. Note that both end surfaces 36 of the first lip 31 and the second lip 32 are formed by simultaneous machining using a known grinder so that the coating liquid does not leak from the manifold 11 or the like inside the slot die 30. It is preferable that the first lip 31 and the second lip 32 are precisely finished so that the lengths in the application width direction are substantially the same. For the same reason, it is preferable that the coupling surface 34 of the side plate 33 facing the both side end surfaces 36 is also precisely finished. Next, when looking at the inner surface 38 of the second lip 32, the manifold 11 is formed, and the manifold 11 is used as a boundary between the mating surface 39 of the second lip 32 and the slot wetted surface 170. The step of depth H is formed over the entire length in the coating width direction. Due to this step, a slot (not shown) is formed between the first lip 31 and the second lip 32 along the coating width direction. The slot gap amount measured in the coating direction perpendicular to the coating width direction is equal to the depth H of the step. Further, the liquid contact surfaces at both ends of the slot are formed by the side plates 33. Therefore, the first lip 31 and the second lip 32 are slot defining members that form a liquid contact surface in the slot application width direction, and the two side plates 33 are slot defining members that form a liquid contact surface at both ends of the slot. Become. The coupling bolt 35 serves as a member coupling means for coupling adjacent slot defining members.

  As described above, the slot die 30 of the present embodiment has a liquid contact surface with the coating liquid, and includes the first lip 31, the second lip 32, and the two side plates 33 that define the shape of the slot. Three of the slot defining members are arranged in the coating width direction. One end of the slot in the direction of discharging the coating liquid (shown by an arrow) communicates with the manifold 11 in the same manner as the slot die 1 described above, and an outlet for discharging the coating liquid from the slot to the outside at the opposite end. Not) is formed. A coating liquid supply port 15 is provided in the central portion of the manifold 11 in the coating width direction. The coating liquid supply port 15 is connected to a pipe (not shown), and is connected to a coating liquid supply means (not shown) outside the slot die 30 via this pipe. Accordingly, the coating liquid supplied by the coating liquid supply means and flowing into the manifold 11 from the coating liquid supply port 15 is guided to both sides in the coating width direction around the coating liquid supply port 15 by the manifold 11 and then to the slot. It flows in and is discharged uniformly from the discharge port. In order to adjust the discharge amount distribution of the coating liquid from both ends of the discharge port in the application width direction, the slot die 1 is placed in the discharge amount adjustment ranges W7 and W8 at both ends of the first lip 31 in the application width direction. The discharge amount adjusting means including the groove 16, the neck portion 23, and the differential screw 17 is provided. Two differential screws 17 are arranged, one for each discharge amount adjustment range W7, W8. Here, the connecting bolt 35 as a member connecting means is provided on the both end faces 36 of the first lip 31 and the second lip 32 on the upstream side (discharging direction) of the coating liquid discharge direction from the neck portion 23 of the first lip 31. It is preferable that the side plate 33 is coupled to the first lip 31 and the second lip 32 by being screwed into a female screw provided on the groove upper portion 21 which is on the opposite side to the outlet. With this configuration, the movement of the groove lower portion 22 and the elastic deformation of the neck portion 23 when the differential screw 17 is operated are freely performed without being constrained by the side plate 33. Further, the groove 16 and the neck portion 23 constituting the discharge amount adjusting means are not provided in the range Wc in the central portion of the first lip 31 in the application width direction. Therefore, the adjustment of the discharge amount distribution in the discharge amount adjustment ranges W7 and W8 can be performed independently without interfering with each other, and also in the discharge amount distribution in the range Wc in the central portion of the slot die 30 in the coating width direction. Has no effect. Therefore, according to the slot die 30, as in the case of the above-described slot die 1, the discharge amount distribution can be adjusted accurately, locally, and quickly in response to the film thickness unevenness that locally changes suddenly at both ends of the coating film. Therefore, a uniform film thickness distribution can be obtained over the entire width in the coating width direction.

  FIG. 6 shows a slot die 40 which is another embodiment of the slot die of the present invention. The slot die 40 includes a first lip 41 and a second lip 42 collectively called a so-called “lip”, a first member 43, a second member 44, and two side plates 45. The first lip 41 and the second lip 42 are integrated by five assembly bolts 7 as lip fastening means after the inner surfaces 47 and 48 face each other. The first member 43 and the side plate 45, and the second member 44 and the side plate 45 are respectively applied to the side end surfaces 49 on both sides in the application width direction of the integrated first lip 41 and second lip 42. It is overlapped in the direction and mounted so as to be fastened together with the connecting bolt 46. That is, the coupling bolt 46 as a member coupling means not only couples the first lip 41 or the second lip 42 and the first member 43 or the second member 44 in the coating width direction, but also the first member. 43 and the second member 44 and the side plate 45 are also coupled in the coating width direction. Note that the side end surfaces 49 of the first lip 41 and the second lip 42 are formed by the simultaneous processing using a known grinder so that the coating liquid does not leak from the internal manifold 11 or the like. It is preferable that the lip 41 and the second lip 42 are precisely finished so that the lengths in the coating width direction are substantially the same. For the same reason, the coupling surfaces 180A and B of the first member 43 and the second member 44 and the coupling surface 180C of the side plate 45 are also surfaces that are coupled in the coating width direction. It is preferable. Next, when looking at the inner surface 47 of the first lip 41, a step having a depth H extending over the entire length in the coating width direction is provided between the mating surface 182 of the first lip 47 and the slot wetted surface 184. Yes. Due to this step, a slot (not shown) is formed between the first lip 41 and the second lip 42 along the coating width direction. One end of the slot in the direction of discharging the coating liquid (the direction shown by the arrow) communicates with the manifold 11A provided on the second lip 42, and the other end is a discharge for discharging the coating liquid to the outside of the slot die 40. An outlet (not shown) is formed. The slot gap measured in the coating direction perpendicular to the coating width direction is equal to the depth H of the step provided in the first lip 41. On the other hand, inside the first member 43, a manifold 11B, a slot 9B, and a discharge port 10B as a coating liquid flow path are provided so as to penetrate the first member 43 in the coating width direction. Similarly, the manifold 11C, the slot 9C, and the discharge port 10C are also provided in the second member 44 so as to penetrate in the coating width direction. These coating liquid channels are substantially the same as the coating liquid channel (manifold 11A, slot, discharge port) formed between the first lip 41 and the second lip 42 when viewed in the coating width direction. Thus, it is formed using a known machining means such as electric discharge machining. Each of the coating liquid flow paths formed inside the first member 43 and the second member 44 and between the first lip 41 and the second lip 42 includes the first member 43 and the second member 44. The two members 44 are respectively connected to the first lip 41 and the second lip 42 at the coupling position where they are coupled in the coating width direction. At this time, it is preferable that the positions of the coating liquid flow paths, particularly the slots and the discharge ports, be matched as much as possible, and the gap amount between the slots is preferably the same as much as possible. Then, both side ends on both sides of the manifold, the slot, and the discharge port in the coating width direction formed inside the slot die 40 by the connected coating liquid flow path are formed by the side plates 45.

  As described above, the slot die 40 of the present embodiment has a liquid contact surface with the coating liquid and defines the first lip 41, the second lip 42, the first member 43, and the second member that define the shape of the slot. 44 and a total of six slot defining members including two side plates 45 are arranged in the coating width direction.

  A coating liquid supply port 15 is provided at the central portion in the coating width direction of the manifold 11 </ b> A formed on the inner surface 48 of the second lip 42. This coating liquid supply port is connected to a pipe (not shown), and is connected to a coating liquid supply means (not shown) outside the slot die 40 via this pipe. Accordingly, the coating liquid supplied by the coating liquid supply means and flowing into the slot die 40 from the coating liquid supply port 15 is guided to both sides in the coating width direction around the coating liquid supply port 15 by the manifolds 11A, 11B, and 11C. The first lip passes through the slot formed between the first lip 41 and the second lip 42 and the slots 9B and 9C formed in the first member 43 and the second member. 41 and the second lip 42 are discharged uniformly from the discharge ports 10B and 10C. In order to adjust the discharge amount of the coating liquid from the discharge ports 10B and 10C at both ends in the coating width direction of the slot die 40, the first member 43 and the second member 44 are similar to the slot die 1 described above. A discharge amount adjusting means comprising a groove 16, a neck portion 23, and a differential screw 17 is provided. Two differential screws 17 are arranged, one for each of the discharge amount adjustment ranges W9 and W10 as the application width direction lengths of the first member 43 and the second member 44, respectively. Here, the coupling bolt 46 has a groove upper portion 21 that is above the neck portion 23 (opposite to the discharge ports 10B and 10C) on the coupling surfaces 180A and B of the first member 43 and the second member 44. After penetrating in the coating width direction, the first lip 41, the second lip 42, and the first member are screwed into female threads provided on the side end surfaces 49 of the first lip 41 and the second lip 42. 43, the second member 44, and the side plate 45 are preferably combined. With this configuration, the movement of the groove lower portion 22 and the elastic deformation of the neck portion 23 in the first member 43 and the second member 44 when the differential screw 17 is operated cause the first lip 41 and the second lip 42 to move. As well as the side plate 45, it is performed freely. Therefore, the adjustment of the discharge amount distribution in the discharge amount adjustment ranges W9 and W10 can be performed independently without interfering with each other, and the discharge amount distribution in the range Wc in the central portion in the coating width direction of the slot die 40 can also be adjusted. Has no effect. Therefore, according to the slot die 40, the discharge amount distribution can be adjusted accurately and quickly locally in response to the film thickness unevenness that suddenly changes locally at both ends of the coating film. A uniform film thickness distribution can be obtained.

  Although several embodiments have been described above, the slot die of the present invention has a liquid contact surface with the coating liquid, and three or more slot defining members that define the shape of the slot are arranged in the coating width direction. A member coupling means for coupling at least two of the slot defining members adjacent in the coating width direction is provided, and at least one of the three or more slot defining members is within a predetermined range at both ends of the ejection port in the coating width direction. It is essential to have a configuration having a discharge amount adjusting means capable of independently adjusting the discharge amount distribution of the coating liquid. That is, as long as this configuration is satisfied, the slot defining members and other arrangement configurations may be in any form.

  Further, the range provided with the discharge amount adjusting means is not limited to both ends of the discharge port in the application width direction, but is a slot defining member (for example, FIG. 1) located in the central portion of the application width direction without any discharge amount adjusting means. The second lip 3, the second lip 32 in FIG. 5, the first lip 41 and the second lip 42 in FIG. You may make it adjust the film thickness distribution of a part.

  The expansion / contraction means for elastically deforming the neck portion 23 is not limited to the differential screw 17 described above. For example, another mechanical means such as a piezoelectric element, a micrometer head, or a linear actuator, or a fluid such as compressed air or hydraulic pressure. You may use the well-known expansion-contraction means using a mechanical means. Further, the discharge amount adjusting means is not limited to the discharge opening degree adjusting means and the slot gap amount adjusting means as shown in the above embodiment. For example, it is possible to use coating liquid viscosity adjusting means as the discharge amount adjusting means, which adjusts the discharge amount distribution by changing the coating liquid viscosity inside the slot die in the coating width direction according to the set temperature of the cartridge heater. It is. In this case, it is preferable that the slot defining members are connected and coupled via a heat insulating material so that the temperature distributions of the slot defining members forming the slots along the coating width direction can be set intermittently.

  The shape and material of the seal plate 12 are not particularly limited as long as the seal plate 12 is not affected by the solvent contained in the coating liquid and can be sealed so that the coating liquid does not leak, but the thickness is the same as the gap amount Ls of the slot. A metal plate such as stainless steel slightly smaller than that, an elastic member whose thickness is slightly larger than the gap amount Ls, and a resin sheet such as polyethylene terephthalate are preferably used.

  The size of the slot gap amount Ls is appropriately set according to the coating liquid used and the coating conditions, but it is possible to maintain the discharge uniformity in the coating width direction and efficiently adjust the film thickness distribution at the coating film end. Therefore, the thickness is preferably 0.03 mm to 1.0 mm, more preferably 0.05 mm to 0.5 mm. Further, the configuration for determining the slot gap amount is not limited to the mode defined by the depth of the step formed on the inner surface of one lip as in the above embodiment. For example, a thin shim may be inserted between the lips, and the slot clearance may be determined by the thickness of the shim.

  The manifold inside the slot die may be provided not only on one lip as in the above embodiment example, but also on both lips, and there is no particular limitation on the cross-sectional shape of the manifold as viewed in the coating width direction. . There is no particular limitation on the front shape of the manifold, and there is a T-type extending in the same cross-sectional shape toward both sides in the application width direction around the application liquid supply port 15 as shown in FIGS. A coat hanger type having an inclined shape toward both sides in the coating width direction around the liquid supply port 15 may be used.

  A well-known device such as a gear pump, a Mono pump, a diaphragm pump, or a syringe pump is preferably used as the coating liquid supply means (not shown). Known filters and valves are provided in the coating liquid flow path between these pumps and the slot die as necessary.

  In the slot die of the present invention, the material of each constituent member such as a lip and other slot defining members is not particularly limited. For example, cemented carbide, ceramics, stainless steel, or those having surface treatment applied thereto are applied. Is done. Of these, stainless steel is preferable because it has chemical resistance and is inexpensive.

  Next, a manufacturing method and manufacturing apparatus for a substrate having a coating film using the slot die of the present invention will be described.

FIG. 7 shows a coating apparatus (die coater 50) using the slot die of the present invention in order to carry out the method for producing a substrate having a coating film of the present invention.
Referring to FIG. 7, a die coater 50 of the present invention is shown. The die coater 50 includes a base 51 on which a pair of rails 52 are provided. A stage 53 is installed on the rail 52. The stage 53 is driven by a linear motor 54 and can freely reciprocate in the X direction indicated by the position of the stage 53. Further, the upper surface of the stage 53 is a vacuum suction surface made up of a plurality of suction holes (not shown), and the substrate 55 that is the substrate to be coated can be sucked and held. The base 51 is provided with a gate-shaped column 56. A pair of lifting device units 100 capable of reciprocating in the vertical direction are provided on both sides of the support column 56 in the coating width direction (direction orthogonal to the X direction). The lifting device unit 100 is provided with a slot die of the present invention. 1 is attached.

  The lifting device unit 100 that moves the slot die 1 up and down includes a holding table 57 that holds the slot die 1, a pair of left and right lifting tables 58 that raise and lower the holding table 57, and a pair of guides that guide the lifting table 58 in the vertical direction. 59, a pair of elevating motors 60, and a pair of ball screws 61 for converting the rotational motion of the elevating motors 60 into linear motion of the elevating table 58. Since the elevating device unit 100 can operate independently on the left and right, the inclination angle of the slot die 1 with respect to the horizontal in the coating width direction can be arbitrarily set. Accordingly, the lip tip surfaces 13 and 14 of the slot die 1 and the base material 55 which is the base material to be coated can be set substantially parallel to the coating width direction of the slot die 1, and the surface of the base material 55 and the slot die 1 A clearance between the lip tip surfaces 13 and 14, that is, a clearance can be provided in an arbitrary size.

  The base 51 is also provided with a wiping unit 110. Similar to the stage 53, the wiping unit 110 can reciprocate freely on the rail 52 in the X direction. The wiping unit 110 includes a wiping head 63, a wiping head driving device 64, a head holder 65, a tray 66, and a wiping unit holding base 67. The wiping head 63 has a shape that matches the shape of the tip of the lip around the discharge port 10 of the slot die 1 and preferably uses an elastic body such as a synthetic resin.

  When wiping is performed using the wiping unit 110, the wiping unit 110 is moved to the lower portion of the slot die 1 in the X direction, the slot die 1 is lowered by the lifting device unit 100, and the wiping head 63 is moved to the slot die 1. The lower end including the discharge port 10 is brought into contact. And the residual coating liquid adhering to the lower end part including the discharge port 10 of the slot die 1 by driving the wiping head 63 brought into contact in the coating width direction which is the longitudinal direction of the slot die 1 by the wiping head driving device 64. And particles can be removed. These residual coating liquid, particles, and the like are received by a tray 66 installed under the wiping head 63 and are collected in a drain tank (not shown) through a drain path (not shown). The tray 66 is applied to the tray 66 for the purpose of exchanging the coating liquid, removing air existing in the slot die 1 and preventing the lip tip surfaces 13 and 14 of the slot die 1 from drying. It can also be used to recover liquids and solvents.

  Next, the coating liquid supply device unit 120 which is a coating liquid supply means for supplying the coating liquid to the slot die 1 is provided with a tank 69 for storing the coating liquid 68. The coating liquid 68 is supplied to the syringe pump 130 through a pump supply path 70 and a suction valve 71 which are pipes connected downstream of the tank 69. The coating liquid 68 supplied to the syringe pump 130 is sent to the manifold 11 of the slot die 1 through the discharge valve 72, the pressure gauge 73, and the filter 74, and the die supply path 75 that is a pipe.

The syringe pump 130 includes a syringe 76, a piston 77, a piston holding table 78 that holds the piston 77, a piston lifting guide 79 that guides the piston holding table 78 in the vertical direction, and a syringe pump that is a vertical drive source for the piston holding table 78. And a syringe pump ball screw 81 for converting the rotational motion of the motor 80 for syringe and the motor 80 for syringe pump into the linear motion of the piston holding base 78. The syringe pump 130 having this configuration fills the inside of the syringe 76 with the coating liquid 68 and pushes it out by the piston 77, thereby supplying a predetermined amount of the coating liquid 68 necessary for coating the base material 55 to the slot die 1. This is a constant capacity pump.
When filling the inside of the syringe 76 with the coating liquid 68, the piston 77 is lowered while the suction valve 71 provided upstream of the syringe 76 is opened and the discharge valve 72 provided downstream of the syringe 76 is closed. Further, when the coating liquid 68 inside the syringe 76 is fed toward the slot die 1, the piston 77 is raised with the suction valve 71 closed and the discharge valve 72 opened. An O-ring 82 is used as a sealing material at the contact portion between the piston 77 and the syringe 76 in order to maintain confidentiality.

  Now, the coating liquid 68 sent from the syringe pump 130 is supplied to the coating liquid supply port 15 of the slot die 1 through the die supply path 75 connected downstream of the syringe 76. Here, the die supply path 75 may be any metal or synthetic resin pipe, but since it is connected to the slot die 1 that moves up and down, the flexible Teflon (registered trademark) is used. It is preferable to use synthetic resin piping such as.

  Note that the coating liquid supply device unit 120 including the linear motor 54, the raising / lowering motor 60, and the syringe pump motor 80, which are operated by the control signal, are all electrically connected to the control device 83. A control command signal is transmitted to each device in accordance with an automatic operation program incorporated in the control device 83 to perform a predetermined operation. Further, when each operation condition needs to be changed, if an appropriate change parameter is input to the operation panel 84, the change parameter is transmitted to the control device 83, and the driving operation can be changed.

  Although not shown in the drawing, around the die coater 50, a loader for supplying a substrate 55 as a substrate to be coated on the stage 53, for example, a glass substrate for a color filter, or for removing the glass substrate from the stage 53. An unloader is provided. For these loaders and unloaders, for example, a cylindrical coordinate system industrial robot can be used as a main component.

  In the above-described embodiment example, the stage 53 is configured to reciprocate. However, the configuration is not limited thereto, and the slot die 1 may be configured to reciprocate with respect to the stage 53. Further, the drive means for reciprocating the stage 53 and the slot die 1 is not limited to the linear motor 54 described above, and a known means such as a ball screw drive by a servo motor can be used. Furthermore, the application liquid supply means for supplying the application liquid 68 of the tank 69 to the slot die 1 is not limited to the syringe pump 130, but a known constant capacity such as a gear pump, a diaphragm pump, a tube pump, or a bellophram pump. A pump may be used, or a pressure feeding method in which a pressure is applied to the tank 69 with air or N 2 gas to transfer the coating liquid may be used.

  Next, a process for manufacturing a color filter, that is, a method for manufacturing a base material having a coating film performed using the die coater 50 will be described.

  In FIG. 7, first, the coating liquid 68 is filled into the tank 69. Next, the tray 66 is moved below the slot die 1, and at the same time, the stage 53 is moved to a position where it does not interfere with the tray 66. Then, the syringe pump 130 is operated, and the slot 9 inside the slot die 1 and the manifold 11 are filled with the coating liquid 68. At this time, excess coating liquid 68 supplied to the slot die 1 is discharged from the discharge port 10 and is received by the tray 66 and discharged from a discharge port (not shown).

  When the inside of the slot die 1 is sufficiently filled with the coating liquid 68, the operation of the syringe pump 130 is stopped, and the coating liquid 68 attached to the lip tip surfaces 13 and 14 of the slot die 1 is wiped using the wiping unit 110. When the above preparatory work is completed, the base material 55 is transferred onto the stage 53 by a loader (not shown), and the base material 55 is sucked and held on the stage 53 in a state where positioning is performed by a positioning device (not shown). In parallel with this, a small amount of coating liquid 68 is discharged from the slot die 1, and the coating liquid 68 adhering to the lip tip surfaces 13, 14 and its periphery is wiped off by the wiping unit 110. The discharge amount of the coating liquid 68 at this time is preferably 200 μl to 2000 μl per 1 m of the length of the discharge port 10 in the coating width direction so that no gap is generated in the vicinity of the discharge port 10 of the slot 9.

Next, the tray 66 is retracted together with the wiping unit 110, and at the same time, the stage 53 is moved below the slot die 1, and when the application start position of the substrate 55 reaches just below the discharge port 10 of the slot die 1, the stage 53 is moved. Stop.
Then, the slot die 1 is lowered by the lifting platform 58 until a predetermined gap (clearance) is provided between the discharge port 10 of the slot die 1 and the base material 55. Next, a certain amount of coating liquid 68 is supplied to the slot die 1, and a bead is formed between the discharge port 10 of the slot die 1 and the base material 55. At this time, it is preferable that the time from when the wiping operation by the wiping unit 110 of the slot die 1 performed immediately before is completed to bead is within 40 seconds, and more preferably within 20 seconds. If the time is longer than this, since the coating liquid 68 filled in the slot 9 is likely to volatilize, the beads are not uniform in the coating width direction of the slot die 1 and coating defects such as coating omission and stripe unevenness occur. .

Subsequently, the coating liquid 68 is continuously supplied to the slot die 1 at a flow rate at which a predetermined film thickness is obtained from the syringe pump 130, and the stage 53 is moved at a constant speed while discharging the coating liquid 68 from the discharge port 10. Then, a coating film 85 is formed on the substrate 55. When the application end position of the base material 55 reaches just below the discharge port 10 of the slot die 1, the discharge of the coating liquid 68 is stopped and the slot die 1 is raised. Further, the stage 53 is moved to the end position. When the stage 53 is stopped, the suction of the base material 55 on the stage 53 is released, the base material 55 is taken out by an unloader (not shown), and conveyed to the next process such as a drying process. After removing the base material 55, the stage 53 is returned to the origin position.
After completion of the above coating operation, the film thickness distribution in the coating width direction of the dried coating film 85 is measured, and if there is a defect in the end part film thickness distribution in a predetermined range, the location corresponding to the defective position The discharge amount distribution is adjusted by the differential screw 17 shown in FIG.

  The viscosity of the coating liquid 68 used is preferably 0.5 mPa · s to 50,000 mPa · s, more preferably 1 mPa · s to 100 mPa · s. The coating liquid 68 is preferably Newtonian in view of coating properties, but a coating liquid having thixotropic properties can also be used. Specific examples of the coating liquid 68 that can be applied include a black matrix for a color filter, an RGB color pixel forming photoresist material, a surface flattening material, and a cell spacer holding photo spacer material.

  As the base material 55, in addition to glass, a metal plate such as aluminum, a ceramic plate, a silicon wafer, or the like may be used.

  As for the coating conditions to be used, the clearance that is the gap between the lip tip surfaces 13 and 14 of the slot die 1 and the base material 55 is preferably 20 μm to 500 μm, more preferably 50 μm to 400 μm, and the coating speed is preferably 0.00. The coating thickness in the wet state is preferably 1 μm to 500 μm, more preferably 5 μm to 300 μm, more preferably 1 m / min to 20 m / min, more preferably 0.5 m / min to 10 m / min.

  The manufacturing method of the base material which has a coating film of this invention is preferably used for manufacture of the member for displays. Examples of the display member include a color filter used in a liquid crystal display, a TFT array substrate, a back plate and a front plate of a plasma display.

  In the above embodiment, application to a single-wafer substrate such as a glass substrate has been described. However, application to a long web (long substrate to be coated) such as a film, a metal sheet, a metal foil, or paper is performed by using the web. This can be realized by supporting it with a roll, bringing the slot die 1 of the present invention close thereto, and discharging the coating liquid from the discharge port 10 of the slot die 1 to the web.

Example 1
Using the die coater 50 shown in FIG. 7 equipped with the slot die 1 of the present invention shown in FIG. 1, a black matrix coating solution for a color filter was applied to a glass substrate as a substrate to be coated.

  The discharge width Wd of the slot die 1 was 355 mm, the adjustment division ranges W1 and W4 were 13 mm, and the adjustment division ranges W2 and W3 were 42 mm. Thereby, the discharge amount adjustment ranges W5 and W6 at both ends of the discharge port were 55 mm. Further, the distance L1 from the coupling position of the first member 4 and the second member 5 shown in FIG. 1 (position of W1 = 13 mm from the discharge port end 27) to the center of the differential screw 17 of the first member 4 is The distance L2 from the same coupling position to the center of the differential screw 17 of the second member 5 was 8 mm. The distance L3 from the coupling position of the second member 5 and the third member 6 (position of W4 = 13 mm from the discharge port end 27) to the center of the differential screw 17 of the second member 5 is 12 mm, from the same coupling position. The distance L4 to the center of the differential screw 17 of the third member 6 was 8 mm. The inclination angle α of the inclined surface 24 shown in FIG. 4 was 30 degrees, the inclination depth B was 0.2 mm, and the distance A from the starting point 26 to the discharge port end 27 was 0.5 mm. The gap amount Ls of the slot 10 has a distribution in the coating width direction, and the average is 101.3 μm and the deviation is ± 0.4 μm. The black matrix coating solution uses carbon black as a light-shielding material, acrylic resin as a binder, and propylene glycol monomethyl ether acetate (PGMEA) as a main solvent. It had photosensitivity. Using the slot die 1 having the above-described configuration, the above-described black matrix coating solution is applied to the entire surface of a 360 mm × 465 mm, 0.7 mm thick glass substrate that has been wet cleaned, and the slot die 1 and the glass substrate are coated at a coating speed of 6 m / min. The coating was performed with a clearance of 120 μm and a wet coating thickness of 10 μm. The substrate on which the coating has been completed is dried at 100 ° C. for 10 minutes with a drying apparatus using a hot plate, and a black coating film having a length of 356 mm in the coating width direction, a length of 465 mm in the coating direction and a film thickness of 1.5 μm is formed. Formed. The uncoated width from the edge of the glass substrate to the edge of the coating film in the coating width direction was 2 mm on both sides.

  Next, after measuring the degree of shading (OD value) of the coating film proportional to the film thickness in the coating width direction with an optical measuring instrument, the measured value of the obtained degree of shading is converted into the film thickness, and FIG. A film thickness distribution before adjustment indicated by a broken line was obtained. This film thickness distribution is shown in terms of a percentage based on the average film thickness in the region excluding 50 mm from the edge of the substrate. And, for each region excluding 10 mm and 50 mm from the substrate edge (region excluding 8 mm and 48 mm from the coating film edge), the following equation (1) is defined from the obtained film thickness measurement value. The film thickness accuracy was calculated, and the values shown in the “Before Adjustment” column of Table 1 were obtained.

Film thickness accuracy (±%) = ((ab) / c) × 100/2 (1)
a: Maximum film thickness in the designated area b: Minimum film thickness in the designated area c: Average film thickness in an area excluding 50 mm from the edge of the substrate.

  When the film thickness distribution before adjustment shown by the broken line in FIG. 9 is seen, the film thickness accuracy in the region excluding 50 mm from the edge of the substrate is ± 1% or less and satisfies the product standard of ± 3% or less, It was a level that could be said to be uniform. However, at the coating film edge from the substrate edge to about 50 mm, the film thickness decreases toward the substrate edge, especially between 5 mm and 20 mm from the substrate edge. The film thickness was reduced. Therefore, in the product region excluding 10 mm from the edge of the substrate, the film thickness accuracy exceeds ± 3%, deviating from the product standard, and product production could not be started. Accordingly, in order to reduce the film thickness unevenness at the coating film end and improve the film thickness distribution shape, the differential screw 17 provided in the slot die 1 is operated to discharge the discharge amount at both ends in the application width direction of the discharge port. Adjustments were made. Specifically, from the coupling position of the first member 4 and the second member 5, L1 is increased so as to increase only the gap amount of the slots at both ends of the application direction of the discharge port. The lead screw 18 of the differential screw 17 at a distance is turned 2/3, the lead screw 18 of the differential screw 17 at a distance L2 from the same coupling position is 1/8 turn, the second member 5 and the third member The lead screw 18 of the differential screw 17 located at a distance L3 from the joint position with the screw 6 is turned 1/2 turn, and the lead screw 18 of the differential screw 17 located at a distance L4 from the same joint position is turned counterclockwise by 2/3 turn. Turned around to adjust the discharge amount distribution. As a result, the film thickness distribution after adjustment shown by the solid line in FIG. 9 and the film thickness accuracy shown in the “after adjustment” column of Table 1 were obtained. As shown by the solid line in FIG. 9, only the film thickness distribution at the coating film end portion is locally improved and improved by the single discharge amount distribution adjustment, and the film thickness distribution in the region excluding 50 mm from the substrate end portion is It did not change before and after adjustment. And, due to the effect of improving the film thickness distribution at the edge of the coating film, the film thickness accuracy in the area excluding 10 mm from the adjusted substrate edge is ± 1% or less, satisfies the product standard, and 10 mm from the substrate edge. Production can now be performed using the product area as the product area.

Comparative Example 1
FIG. 8 is a perspective view showing a conventional slot die 200. The conventional slot die 200 shown here is mounted on the die coater 50 of FIG. A black coating film was formed on the glass substrate.

  Referring to FIG. 8, the slot die 200 includes a first lip 201 and a second lip 202 corresponding to the first lip 2 and the second lip 3 of the slot die 1 in the first embodiment, and the first lip. 201 and the second lip 202 are composed of two seal plates 212 sandwiched at both ends in the coating width direction which is the longitudinal direction, and the first lip 201 is made of a single member, and discharge amount adjusting means Except that the groove 216 and the neck portion 223 constituting the rim are continuously formed over the entire width in the coating width direction, and the differential screw 17 is disposed over the entire width in the coating width direction. there were. Then, all of the discharge dimensions, the slot gap amount, the shape and position of the inclined surface of the lip tip surface, etc., were made the same as the slot die 1. Further, four differential screws 217 are provided at positions 5 mm and 25 mm inward from both ends in the application width direction of the discharge port (positions 7.5 mm and 27.5 mm from the end of the glass substrate), and further 50 mm inside thereof. A total of 9 pieces of 5 pieces were arranged at the pitch position.

After the first application, the film thickness distribution before adjustment indicated by the broken line in FIG. 10 and the film thickness accuracy shown in the “before adjustment” column of Table 1 calculated from the equation (1) were obtained. The film thickness distribution shown in FIG. 10 is converted into a percentage and displayed as in FIG. 9 of the first embodiment. In addition, the length from the glass substrate end to the coating film end in the coating width direction, that is, the uncoated width was 2 mm on both sides.
As shown by the broken line in FIG. 10, the film thickness distribution before the adjustment was a shape in which the film thickness rapidly decreased at the coating film end as in the case before the adjustment in Example 1. For this reason, as shown in the “Before Adjustment” column of Table 1, the film thickness accuracy in the area excluding 10 mm from the edge of the substrate exceeded ± 2%, which was out of the product standard. Next, the discharge amount distribution at both ends of the discharge port in the application width direction is operated by operating three differential screws 217 on each side (total of six) at 5 mm, 25 mm, and 75 mm from both ends of the discharge port in the application width direction. Adjustments were made to try to improve the film thickness distribution at the edges of the coating. Specifically, the differential screw 217 at the positions of 5 mm and 25 mm from both ends of the application width direction of the discharge port is operated so as to increase the discharge amount by increasing the gap amount of the slot, and then at the position of 75 mm. In order to reduce the discharge amount that increases excessively due to the adjustment, the differential screw 217 is operated so as to reduce the discharge amount by decreasing the slot gap amount. However, with the conventional slot die 201, the discharge amount distribution cannot be precisely adjusted locally at both ends in the application width direction of the discharge port, and the film thickness distribution at the coating film end has not improved. The application and adjustment were repeated five times in total, but only the film thickness distribution after adjustment as shown by the solid line in FIG. 10 was obtained, and the film thickness distribution at the coating film end could not be made uniform. As a result, as shown in the “after adjustment” column of Table 1, the film thickness accuracy in the region excluding 10 mm from the edge of the substrate was almost the same as before the adjustment, exceeding ± 2%. Furthermore, although the discharge amount distribution adjustment was performed so as to change only the film thickness distribution at the coating film edge, the film thickness distribution at the center in the coating width direction also changed, and 50 mm was excluded from the adjusted substrate edge. The film thickness accuracy in the region was ± 1.4%, which was worse than before the adjustment and was out of product specifications.

Example 2
The slot die 1 in which the film thickness distribution at both ends of the substrate is improved by adjusting the discharge amount distribution at both ends in the coating width direction in Example 1, the same die coater 50, black matrix coating liquid, glass substrate as in Example 1, In addition, a black coating film having a film thickness of 1.5 μm was sequentially formed on 1000 wet-cleaned glass substrates depending on the coating and drying conditions. Further, after exposure, development and peeling, heating on a hot plate at 260 degrees for 30 minutes and curing to create a black matrix film with a thickness of 1 μm and an OD value of 3.5 in a lattice pattern did. In addition, although the film thickness distribution of the obtained 1000 black coating films was confirmed by sampling inspection in the middle, the film thickness distribution after adjustment shown by the solid line in FIG. 9 and the “after adjustment” column in Table 1 are shown. The film thickness accuracy was reproduced.

  Next, using the slot die 1 and the die coater 50 that were used in the production of the black matrix film in Example 1 as they were, RGB color coating solutions were sequentially applied onto the glass substrate. First, the slot die 1 in which the black matrix coating solution had been applied while being mounted on the die coater 50 was sufficiently replaced and washed with PGMEA, which is a solvent for the black matrix coating solution. Next, the inside of the slot die 1 was filled with the R color coating liquid, and the air remaining inside was discharged to the outside by a predetermined air bleeding operation. Then, only one coating solution for R color was first applied onto the glass substrate at a coating speed of 6 m / min, a clearance of 120 μm between the slot die 1 and the glass substrate, and a wet coating thickness of 20 μm. The coating solution for R color had a photosensitivity adjusted by mixing an acrylic resin as a binder, PGMEA as a solvent, and Pigment Red 177 as a pigment at a solid content concentration of 10%, and adjusting the viscosity to 5 mPa · s. . The substrate on which the coating has been completed is dried at 90 ° C. for 10 minutes by a drying apparatus using a hot plate, and an R color coating film having a length of 356 mm in the coating width direction, a length of 465 mm in the coating progress direction, and a film thickness of 2 μm is formed. Created. And as a result of measuring the film thickness of this R color coating film after drying in the coating width direction with an optical measuring instrument, Table 2 calculated from the film thickness distribution shown by the broken line in FIG. 11 and the above equation (1) The film thickness accuracy values shown in the “Before Adjustment” column were obtained.

  When comparing the film thickness distribution before adjustment of the R color coating film shown by the broken line in FIG. 11 and the film thickness distribution after adjustment of the black coating film shown by the solid line in FIG. Despite being used, the coating thickness and the coating / drying conditions have changed, so the film thickness distribution at the edge of the coating changes greatly. It became. When the film thickness accuracy of the R color coating film shown in the “Before Adjustment” column of Table 2 is compared with the film thickness accuracy of the black coating film of Table 1, the R color coating film in the region excluding 50 mm from the edge of the substrate. The film thickness accuracy is ± 0.65%, which almost reproduces the film thickness accuracy result of the black coating film, but the film thickness accuracy of the R color coating film in the area excluding 10mm from the edge of the substrate is ± 3.24%. The black coating greatly deteriorated from ± 1% or less.

  Therefore, only the two differential screws 17 provided at both ends of the second member 5 in the application direction are operated so that the gap amount of the slot is reduced, and the discharge amount distribution at both ends of the discharge port in the application width direction. Adjustment was made only once. As a result, the film thickness distribution indicated by the solid line in FIG. 11 and the value of the film thickness accuracy shown in the “after adjustment” column of Table 2 were obtained. As shown by the solid line in FIG. 11, the film thickness distribution at the coating film edge is improved and improved, and the film thickness accuracy in the area excluding 10 mm from the substrate edge as shown in the “after adjustment” column of Table 2 is In the R color coating film, the area excluding 10 mm from the edge of the substrate was defined as the product area, and the film thickness accuracy could be kept within ± 1% of the product standard.

  After the above-described film thickness distribution adjustment is completed, the substrate on which the black matrix pattern is formed is wet-cleaned, and the R color coating solution is applied in a wet state with a coating thickness of 20 μm, and the clearance between the slot die and the substrate is 120 μm. 1000 sheets were applied at 6 m / min. The coated substrate is dried on a hot plate at 90 ° C. for 10 minutes, and then exposed, developed, and peeled off, leaving an R color coating film with a thickness of 2 μm only on the R pixel portion, and heated on a 260 ° hot plate for 30 minutes. Then I did a cure. Subsequently, the G color coating solution is applied to the black matrix, and the R color coating film is formed on the substrate. The G color coating solution is applied in a wet state to a coating thickness of 20 μm, and the clearance between the slot die 1 and the substrate is 6 μm at 150 μm. / Min, dried on a hot plate at 100 ° C. for 10 minutes, then exposed, developed, and peeled off, leaving a G color coating with a thickness of 2 μm only on the G color pixel, and a 260 ° hot plate For 30 minutes to cure. Furthermore, a B-color coating solution is applied to a substrate on which a black matrix, R-color, and G-color coating film is formed at a coating thickness of 22 μm in a wet state and a clearance of 120 μm between the slot die and the substrate at 6 m / min. Then, after drying for 10 minutes on a hot plate at 100 ° C., exposure, development and peeling are performed, leaving a B color coating film with a thickness of 2.2 μm only on the B color pixel part, and heating for 30 minutes on a 260 ° C. hot plate Then I did a cure. The G-color coating liquid is an R-color coating liquid, the pigment is Pigment Green 36, the solid concentration is 10%, and the viscosity is adjusted to 5 mPa · s. The B-color coating liquid is an R-color coating liquid. The pigment was Pigment Blue 15 and the viscosity was adjusted to 5 mPa · s at a solid content concentration of 10%.

  For the G and B coating solutions, the coating solution is replaced with the slot die 1 in the same manner as in the case of the R coating solution described above before the coating is continuously performed. The discharge amount distribution adjustment at both ends in the application width direction of the discharge port was performed only once so that the film thickness accuracy in the area excluding 10 mm was ± 1% or less.

  Finally, ITO was deposited by sputtering. With this manufacturing method, 1000 color filters were produced. The obtained color filter had a very uniform and uniform chromaticity over the entire surface of the substrate except for 10 mm from the edge of the substrate, and was satisfactory in quality. By using the slot die 1 of the present invention according to Examples 1 and 2, the slot die can be shared in forming various coating films of each color, and a high-quality color filter can be quickly and efficiently manufactured. Has been demonstrated.

  The present invention is mainly used in the field of manufacturing display members such as color filters used in liquid crystal displays, TFT array substrates, and back and front plates of plasma displays. Even in the manufacturing field of circuits, semiconductors, lithium batteries, multilayer capacitors, etc., it can be used to a great extent when manufacturing high-quality products having a uniform film thickness up to the coating film end.

It is the perspective view which showed the slot die 1 which is one embodiment of this invention. FIG. 3 is an exploded perspective view showing the slot die 1. FIG. 4 is a cross-sectional view of the slot die 1 after assembly. FIG. 3 is an enlarged front view of a part of the inner surface of the slot die 1. It is the perspective view which exploded and showed the slot die 30 which is another one embodiment of this invention. It is the perspective view which disassembled and showed the slot die 40 which is another one Embodiment of this invention. It is a schematic block diagram which shows an example of the coating device (die coater) carrying the slot die of this invention. 6 is a perspective view showing a conventional slot die 200 used in Comparative Example 1. FIG. 5 is a film thickness distribution diagram showing a change in film thickness distribution in the coating width direction before and after film thickness adjustment in Example 1. FIG. 6 is a film thickness distribution diagram showing changes in film thickness distribution in the coating width direction before and after film thickness adjustment in Comparative Example 1. FIG. 6 is a film thickness distribution diagram showing changes in film thickness distribution in the coating width direction before and after film thickness adjustment in Example 2. FIG.

Explanation of symbols

1 Slot die of the present invention (Examples 1 and 2)
2 1st lip 3 2nd lip 4 1st member 5 2nd member 6 3rd member 7 Assembly bolt 8 Connection bolt (member connection means)
9 Slot 10 Discharge port 11 Manifold 12 Seal plate 13 Lip tip surface 14 of the first lip 2 Lip tip surface 15 of the second lip 3 Coating liquid supply port 16 Groove 17 Differential screw 18 Lead screw 19 Child screw 20 Nut 21 Groove upper portion 22 Groove lower portion 23 Neck portion 24 Inclined surfaces 25A, B, C, D Slot liquid contact surface 26 Starting point 27 of inclined surface 24 Discharge port end 28A, B, C Inner surface 29 Inner surface 30 Slot die 31 of the present invention Lip 32 Second lip 33 Side plate 34 Connection surface 35 Connection bolt (member connection means)
36 both end faces 37 inner surface 38 inner surface 39 mating surface 40 slot die 41 of the present invention first lip 42 second lip 43 first member 44 second member 45 side plate 46 coupling bolt (member coupling means)
47 inner surface 48 inner surface 49 side end surface 50 die coater 51 base 52 rail 53 stage 54 linear motor 55 base material (coating base material)
56 Strut 57 Holding stand 58 Lifting stand 59 Guide 60 Lifting motor 61 Ball screw 63 Wiping head 64 Wiping head driving device 65 Head holder 66 Tray 67 Wiping unit holding stand 68 Coating liquid 69 Tank 70 Pump supply path 71 Suction valve 72 Discharge valve 73 Pressure gauge 74 Filter 75 Die supply path 76 Syringe 77 Piston 78 Piston holding base 79 Piston lift guide 80 Syringe pump motor 81 Syringe pump ball screw 82 O-ring 83 Controller 84 Operation panel 85 Coating film 100 Lifting device unit 110 Wiping unit 120 Coating liquid supply device unit 130 Syringe pump 160 Lip tip end 162 Upper edge 164A, B Side end surface 165 First member coupling surface 166 Second member 5 coupling surface 167 Third member 6 17 Slot contact surface 180A, B, C Bonding surface 182 Matching surface 184 Slot contact surface 200 Conventional slot die 201 First lip 202 Second lip 216 Groove 217 Differential screw 223 Neck portion A Distance B Inclination depth L1 Distance L2 from the coupling position of the first member 4 and the second member 5 to the center of the differential screw 17 of the first member 4 The second position from the coupling position of the first member 4 and the second member 5 Distance L3 to the center of the differential screw 17 of the member 5 Distance L4 from the coupling position of the second member 5 and the third member 6 to the center of the differential screw 17 of the second member 5 The distance Ls from the coupling position with the third member 6 to the center of the differential screw 17 of the third member 6 The gap amount LS1 The vertical length LS2 from the position S to the discharge port 10 The lead screw 18 and the child from the slot forming surface 25A The length of the screw 19 to the common center line Lx Vertical length H from position S to any position Step S Positions W1, W2, W3, W4 Adjustment division ranges W5, W6, W7, W8, W9, W10 Discharge amount adjustment range Wd Discharge width α Inclination Corner

Claims (7)

A coating liquid supply port for supplying the coating liquid to the slot die, a manifold for guiding the coating liquid supplied from the coating liquid supply port in the coating width direction, and a slit-like discharge extending in the coating width direction for discharging the coating liquid In a slot die having an outlet, a slot communicating the manifold and the discharge port,
(1) Three or more slot defining members having a liquid contact surface with the coating liquid and defining the shape of the slot are arranged in the coating width direction;
(2) A member coupling means for coupling at least two slot defining members adjacent to each other in the coating width direction is provided,
(3) At least one of the three or more slot defining members has a discharge amount adjusting means capable of independently adjusting the discharge amount distribution of the coating liquid in a predetermined range at both ends of the discharge port in the coating width direction.
A slot die characterized by that. 2. The slot die according to claim 1, wherein at least one of a pair of liquid contact surfaces along the coating width direction of the slot is formed by the three or more slot defining members arranged. 2. The slot die according to claim 1, wherein the slot defining members disposed at both ends in the coating width direction of the slot defining member are members that form liquid contact surfaces at both ends in the coating width direction of the slot. . 4. The slot die according to claim 1, wherein the discharge amount adjusting means is a gap amount adjusting means for adjusting a gap amount of the slot. 5. The front end portion of the slot die including the discharge port is further provided with limiting means for limiting the positions of both ends of the coating liquid discharged from the discharge port in the coating width direction. A slot die according to any one of the above. The slot die according to any one of claims 1 to 5, a pipe connected to the coating liquid supply port of the slot die, and a coating liquid supply for supplying the coating liquid to the coating liquid supply port via the pipe A substrate having a coating film, characterized by comprising: means; and a substrate to be coated that is spaced from the discharge port of the slot die; and a moving means that relatively moves at least one of the slot dies. Material manufacturing equipment. A slot die according to any one of claims 1 to 6, wherein a coating liquid is discharged from an outlet of the slot die, and a substrate to be coated that is spaced from the outlet of the slot die and the substrate Relatively moving at least one of the slot dies, the coating liquid discharged from the discharge port is applied onto the substrate to be coated, and a coating film made of the coating liquid is formed on the substrate to be coated. The manufacturing method of the base material which has a coating film to perform.

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