JP4763325B2 - Coating liquid coating method, coating liquid coating apparatus, and optical film manufacturing method - Google Patents

Description

The present invention relates to a coating liquid coating method, a coating liquid coating apparatus, and an optical film manufacturing method , and more particularly to a technique for accurately discharging a coating liquid.

  Conventionally, as a coating apparatus for coating a coating film having a desired thickness on the surface of a web (support), a bar coater method, a reverse roll coater method, a gravure roll coater method, a slot die coater method such as an extrusion coater, etc. are known. It has been. Among these, slot die coater type coating apparatuses are frequently used because they can coat thin layers at a higher speed than other systems.

  In the slot die coater system represented by the extrusion coater, the coating liquid is applied onto the web by the bead of the coating liquid installed between the web and the slot die. However, factors such as device manufacturing errors and disturbances are applied. May have a significant impact on accuracy. In particular, when a highly accurate coating solution is required as in the case of forming a thin coating film, the influence of such factors cannot be ignored. Against this background, several methods have been proposed for obtaining a uniform coating film while preventing defective coating.

  For example, in Patent Document 1, the surface of the coating width regulating member provided on both sides of the upstream lip and the downstream lip that faces the web is formed flush with the surface of the lip portion that faces the web. A coating apparatus is disclosed. The purpose of this coating apparatus is to reproduce the slot gap with high accuracy, to improve the assembly workability, and to prevent the occurrence of a coating film abnormality.

  Patent Document 2 discloses a coating apparatus in which the gap between the tip lip and the web is adjusted, and the relative positional relationship between the tip position of the width regulating member and the tip position of the tip lip is adjusted. The purpose of this coating apparatus is to stabilize the ear portion of the bead and form a good planar coating film.

Patent Document 3 discloses a coating apparatus in which a concave portion or a convex portion is formed on the upper edge portion of a spacer that regulates the coating width. This coating apparatus is intended to suppress the spreading phenomenon.
Japanese Patent Laid-Open No. 7-80380 JP 2003-260402 A JP 2001-170542 A

  As described above, in a general coating apparatus in which an extrusion coater or the like is used, a coating film having a desired width can be formed on a web by regulating the coating width of the coating liquid by a width regulating member (spacer). Many.

  FIG. 13 to FIG. 15 are views showing a typical arrangement relationship between the slot die 18 and the width regulating plate 60 having an overbite structure, and the state in which the tip portions of the slot die 18 and the width regulating plate 60 are viewed from the side. Show. Many of the conventional width regulating plates 60 have a front end surface 62 formed substantially parallel to the lip land 16 of the slot die 18. For example, the front end surface 62 of the width regulating plate 60 used for the slot die 18 having an overbite structure is formed to be substantially flush with the downstream lip land 16B (see FIG. 13), or substantially flush with the upstream lip land 16A. (See FIG. 14), or formed between the upstream lip land 16A and the downstream lip land 16B (see FIG. 15).

  However, the conventional width regulating plate 60 represented by FIGS. 13 to 15 forms a step portion between the upstream lip land 16A and / or the downstream lip land 16B. For this reason, a part of the coating liquid discharged from the slot die 18 wraps around the step portion, and the edge portion (width edge portion) of the coating film formed on the web may be disturbed.

  On the other hand, a technique for preventing the coating liquid from flowing around by providing an uneven portion on the width regulating member has been proposed (see Patent Document 2). However, when the distance between the slot die and the lip land is very narrow, the convex portion formed on the width regulating member may disturb the coating film on the web. On the other hand, when the concave portion is formed in the width restricting member, the amount of the coating liquid that wraps around can be reduced, but the coating liquid may not be sufficiently prevented from wrapping around. Therefore, it is desired to propose a new method for preventing the coating liquid from flowing around.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coating liquid coating method and a coating apparatus capable of preventing the coating liquid from flowing around and discharging the coating liquid with high accuracy, and such a coating. It is providing the optical film containing the coating layer obtained by a method or a coating device.

In order to achieve the above object, one aspect of the present invention is to discharge a coating liquid from a slot of a slot die toward a surface of a support that continuously runs in a state supported by a backup roller, and to provide the slot die and the support. In addition, the present invention relates to a coating liquid coating method in which a support upstream side of a bead of a coating liquid laid between and is decompressed by a decompression chamber, and the coating liquid is applied to the surface of the support by the bead. In this coating solution coating method, the downstream die tip surface downstream of the slot among the tip surfaces of the slot die is disposed closer to the support than the upstream die tip surface upstream. The width restricting member for restricting the coating width of the coating liquid discharged from the slot toward the support is inserted into the slot, and the leading end surface of the width restricting member is substantially continuous with the leading end surface of the upstream die. And substantially continuous with the downstream die tip surface.

  According to the present invention, the upstream die front end surface and the downstream die front end surface of the slot die and the front end surface of the width restricting member are substantially continuous. Therefore, between the front end surface of the width restricting member and the front end surface of the slot die. The formed step portion can be eliminated or the size of the step can be reduced. As a result, the coating liquid can be prevented from wrapping around and a coating film of good quality can be generated. Here, “substantially continuous” refers to, for example, a state in which there is almost no step and the connection is made almost without interruption.

The distance between the front Symbol upstream die tip surface the width regulating member side of the end portion and the width regulating end portion of the upstream side die tip side of the distal end surface of the member is at 10μm or less than 0 .mu.m, the downstream The distance between the end of the side die tip surface on the width regulating member side and the end of the width regulating member on the downstream die tip surface is 0 μm or more and 10 μm or less, and the upstream die tip surface The end portion on the width regulating member side may be the same as or protruding from the end portion on the upstream die tip surface side in the tip surface of the width regulating member with respect to the discharge direction of the coating liquid.

  By arranging the “end of the upstream die tip surface” and the “end of the downstream die tip surface” and the “end of the tip surface of the width regulating member” in this manner, the tip of the width regulating member The surface can be substantially continuous with the upstream die tip surface and can be substantially continuous with the downstream die tip surface. Here, “equal or projecting with respect to the discharge direction of the coating liquid” means that in the present invention, it is disposed at the same distance or close to the support, and the discharge direction of the coating liquid. Refers to the state of not retracting. Accordingly, when the end of the upstream die end surface on the width regulating member side is defined as a reference (0), the direction approaching the support is defined as “+”, and the direction away from the support is defined as “−”. The end of the side die tip surface on the width regulating member side is arranged in a range defined by 0 μm to +10 μm. Similarly, the end on the width regulating member side of the downstream die front end surface is set as a reference (0), the direction approaching the support is the “+” side, and the direction away from the support is the “−” side. Of the downstream die front end surface, the end on the width regulating member side is disposed in a range defined by −10 μm to +10 μm.

The end surface of the front Symbol width regulating member with respect to the vertical direction on the downstream side die tip surface, with no projecting from an end portion of the downstream die tip side of the tip end surface of the width regulating member, wherein The end of the width regulating member may not be retracted from the end on the upstream die tip surface side in the direction perpendicular to the upstream die tip surface. By forming the front end surface of the width regulating member in this way, it is possible to effectively prevent the coating liquid from entering the front end surface of the width regulating member.

The surface tension of the previous SL coating solution may be less than or equal to 30 mN / m. When using such a low-viscosity coating solution that is relatively disturbed, the above-described coating method that prevents the coating solution from flowing in is particularly effective, and the coating solution can be discharged stably. .

The contact angle of the coating liquid for the previous SL width regulating member may be 30 degrees or more. When the width regulating member is not easily wetted by the coating liquid, particularly when the contact angle of the coating liquid with respect to the width regulating member is 30 degrees or more, the above-described coating method for preventing the coating liquid from flowing is effective, and the coating liquid is stable. Can be discharged.

At least a portion the coating liquid is in contact of the previous SL width regulating member may be coated with a polymer. When adjusting the difficulty of wetting of the width regulating member by the coating liquid using the width regulating member coated with the polymer, the above-described coating method for preventing the coating liquid from flowing in is effective, and the coating liquid is stabilized. Can be discharged.

Another aspect of the invention relates to an optical film comprising at least one coating layer obtained by the above-described coating solution coating method.

  ADVANTAGE OF THE INVENTION According to this invention, the coating layer obtained in the state in which the wraparound of the coating liquid was reduced is used, and a high quality optical film is provided.

According to another aspect of the invention, the coating liquid is discharged from the slot of the slot die toward the surface of the support that continuously runs while being supported by the backup roller, and between the slot die and the support. The present invention relates to a coating liquid coating apparatus in which a support upstream side of a bead of coating liquid to be installed is decompressed by a decompression chamber, and the coating liquid is coated on the surface of the support by the bead. In this coating solution coating apparatus, the downstream die tip surface downstream of the slot among the tip surfaces of the slot die is disposed at a position closer to the support than the upstream die tip surface upstream. The width restricting member for restricting the coating width of the coating liquid discharged from the slot toward the support is inserted into the slot, and the leading end surface of the width restricting member is substantially continuous with the leading end surface of the upstream die. And substantially continuous with the downstream die tip surface.
According to another aspect of the invention, the coating liquid is discharged from the slot of the slot die toward the surface of the support that continuously runs while being supported by the backup roller, and between the slot die and the support. In the coating liquid coating method, the upstream side of the support bead of the coating liquid to be installed is depressurized by a decompression chamber, and the coating liquid is applied to the surface of the support by the bead. A downstream die tip surface downstream of the slot is disposed at a position closer to the support than an upstream upstream die tip surface, and the slot is discharged from the slot toward the support. A width regulating member for regulating the coating width of the coating liquid is inserted, and the leading end surface of the width regulating member is substantially continuous with the leading end surface of the upstream die and the downstream die tip A distance between the end of the width restricting member on the upstream die tip surface side and the support body is substantially continuous with the surface and provided non-parallel to the upstream die tip surface and the downstream die tip surface. The end of the downstream die tip surface side of the member is larger than the distance between the support and the upstream die of the upstream die tip surface on the width regulating member side and the upstream die of the width regulating member tip surface. The distance from the end portion on the front end surface side is 10 μm or less, the end portion on the width regulating member side of the downstream die end surface, and the end portion on the downstream die front end side of the front end surface of the width regulating member Is a distance of 0 μm or more and 10 μm or less, and a coating liquid application method in which an end of the width regulating member on the upstream die tip surface side protrudes beyond an end of the upstream die tip surface on the width regulating member side About.
Another aspect of the invention relates to a method for producing an optical film including a step of forming at least one coating layer obtained by the coating method of the coating solution.
According to another aspect of the invention, the coating liquid is discharged from the slot of the slot die toward the surface of the support that continuously runs while being supported by the backup roller, and between the slot die and the support. In the coating liquid coating apparatus, the upstream side of the support bead of the coating liquid to be installed is decompressed by a decompression chamber, and the coating liquid is applied to the surface of the support by the bead. A downstream die tip surface downstream of the slot is disposed at a position closer to the support than an upstream upstream die tip surface, and the slot is discharged from the slot toward the support. A width regulating member for regulating the coating width of the coating liquid is inserted, and the leading end surface of the width regulating member is substantially continuous with the leading end surface of the upstream die and the downstream die tip A distance between the end of the width restricting member on the upstream die tip surface side and the support body is substantially continuous with the surface and provided non-parallel to the upstream die tip surface and the downstream die tip surface. The end of the downstream die tip surface side of the member is larger than the distance between the support and the upstream die of the upstream die tip surface on the width regulating member side and the upstream die of the width regulating member tip surface. The distance from the end portion on the front end surface side is 10 μm or less, the end portion on the width regulating member side of the downstream die end surface, and the end portion on the downstream die front end side of the front end surface of the width regulating member The distance is 0 μm or more and 10 μm or less, and the coating device for coating liquid that projects the end portion on the upstream die tip surface side of the width regulating member more than the end portion on the width regulating member side of the upstream die tip surface About.

  According to the coating liquid coating method and coating apparatus of the present invention, the upstream die tip surface and the downstream die tip surface of the slot die and the tip surface of the width regulating member are substantially continuous. The stepped portion formed between the front end surface of the slot die is reduced or eliminated, and the coating liquid can be effectively prevented from entering around the width regulating member.

  Moreover, the optical film and antireflection film of the present invention include a coating layer produced by a coating solution that is stably discharged while preventing the coating solution from wrapping around, and has good quality.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a configuration diagram of a slot die coater type coating system 10 according to an embodiment of the present invention. FIG. 2 is a perspective view showing a state in which a part of the slot die 18 is cut. In addition, the arrow in the vicinity of the backup roller 12 and the web 14 in the drawing indicates the “conveying direction of the web 14 by the backup roller 12”, that is, the “traveling direction of the web 14” in the present embodiment.

  In the extrusion-type slot die coater type coating system 10 according to the present embodiment, the coating liquid is applied from the slot 24 of the slot die 18 toward the surface of the web (support) 14 that continuously runs while being supported by the backup roller 12. As a result, the beads 20 of the coating liquid are cross-linked between the slot die 18 and the web 14. Then, in a state where the web upstream side of the bead 20 is decompressed by the decompression chamber 26, the coating liquid of the bead 20 is applied to the surface of the web 14 that continuously travels, and a coating film (coating layer) is generated on the web 14.

  With reference to the position where the coating liquid is applied by the slot die 18 (hereinafter, also referred to as “application position”), the portion preceding the application position with respect to the traveling direction of the web 14 is referred to as “web upstream”, and the subsequent stage. This portion is referred to as “web downstream”. Therefore, in the horizontal slot die 18 shown in FIG. 1, the lower side of the bead 20 is the “web upstream side” and the upper side of the bead 20 is the “web downstream side”. A web width direction perpendicular to the web conveyance direction is referred to as a “web width direction”.

  The slot die 18 has a manifold 22 provided inside the main body 50 and a slot 24 extending from the manifold 22 to the tip of the slot die 18. The slot die 18 includes two blocks, an upstream die block 18A and a downstream die block 18B. The manifold 22 and the slot 24 are part of the boundary between the upstream die block 18A and the downstream die block 18B. It has become. Thus, by making the slot die 18 have a multi-block structure, the manufacturing accuracy of the slot die 18 is increased and post-processing such as cleaning is facilitated. The specific shape and size of the slot die 18 are determined based on its own weight, the environment during use, the temperature of the coating liquid, the manufacturing specification limit, and the like.

  The tip end portion of the slot die 18 is formed in a tapered shape, and the tip end is called a lip land 16. The lip land 16 on the web upstream side (lower side in FIG. 1) of the slot 24 is referred to as upstream lip land 16A, and the lip land 16 on the downstream side (upper side in FIG. 1) is referred to as downstream lip land 16B.

  Generally, the length in the direction perpendicular to the coating width of the upstream lip land portion 16A is used in the range of 100 μm to 1 mm, and the length of the downstream lip land portion 16B is used in the range of 30 μm to 100 μm. . Further, the length of the upstream lip land portion 16A is not particularly limited, but 200 μm to 1 mm is preferably used. Further, the straightness of the tip of the lip can be set to 10 μm or less, preferably 5 μm or less per meter on both the upstream side and the downstream side with respect to the width direction.

  The slot die 18 of the present embodiment has an over bite structure, and the downstream lip land 16B is disposed closer to the web 14 wound around the backup roller 12 than the upstream lip land 16A. Such an over bite structure is formed substantially uniformly over the entire length of the slot die 18 in the web width direction. The distance L between the upstream lip land 16A and the downstream lip land 16B with respect to the coating liquid discharge direction (see arrow A) is referred to as “overbite amount”.

  Generally, the distance between the web (support) 14 and the downstream lip land 16B is preferably about 20 μm to 200 μm, and the overbite amount is used in the range of 30 μm to 120 μm.

  In order to satisfy the above shape, as a measure for improving the strength and surface condition of the lip tip, the material of the slot die 18 including at least this portion is made of a super hard material mainly composed of tungsten carbide (hereinafter referred to as WC). By using a super hard material, it can be used as a measure against lip abrasion due to the coating liquid being discharged at the same time as the uniformity of the surface shape. This is particularly effective when applying a magnetic liquid containing an abrasive as the coating solution. As the super hard material, a material formed by bonding a WC carbide crystal having an average particle diameter of 5 μm with a bonding metal such as Co is used. However, the bonding metal is not limited to this, and includes Ti, Ta, Nb, and the like. Various metals can be used. In addition, as long as the average particle diameter of a WC crystal is 5 micrometers or less, you may use the thing of arbitrary average particle diameters.

  In general, these overbite structures have a low lip clearance structure in which the gap between the lip land 16 and the web 14 is narrow, thereby reducing the pressure loss of the coating liquid downstream of the bead 20 and reducing the reduced pressure value in the reduced pressure chamber 26. can do. Therefore, when adopting these structures, the fluctuation of the bead 20 is suppressed, the coating liquid can be stably coated on the web 14, and a coating film having a highly accurate surface shape is provided. Can do.

  The manifold 22 is a liquid reservoir that spreads the coating liquid supplied to the slot die 18 in the coating width direction (web width direction), and extends in the web width direction (longitudinal direction). The manifold 22 has a substantially circular cross-sectional shape, and forms a hollow portion having substantially the same cross-sectional shape along the web width direction. The effective length of the manifold 22 in the web width direction is set equal to or slightly longer than the coating width for the web 14. The manifold 22 is also referred to as “pocket”.

  A coating liquid tank 44 that stores the coating liquid is connected to the manifold 22 via a coating liquid supply pipe 46, and a coating liquid pump that sends the coating liquid from the coating liquid tank 44 to the manifold 22 is connected to the coating liquid supply pipe 46. 42 is provided.

  As shown in FIG. 2, closing plates 54 are provided at both ends of the main body 50 in the web width direction. The manifold 22 is connected to a coating solution discharge pipe 52 for drawing the coating solution from the manifold 22. The coating liquid supply pipe 46 and the coating liquid discharge pipe 52 pass through the closing plate 54 and communicate with the manifold 22.

  The supply method of the coating liquid to the manifold 22 may be any method as long as the coating liquid can be appropriately supplied to the manifold 22. For example, not only a method of supplying the coating liquid from one end side of the manifold 22 but also a method of supplying the coating liquid from the central portion of the manifold 22 and a stopper for preventing the coating liquid from leaking out at both ends of the manifold 22 are provided. A system in which a new coating liquid is supplied from one end of the manifold 22 and a part of the coating liquid extracted from the other end is circulated again to the one end can be used. In addition, the cross-sectional shape of the manifold 22 is not limited to a substantially circular shape, and may be a semicircular shape, a rectangular shape such as a trapezoid, or a similar shape.

  The slot 24 constitutes a narrow flow path for the coating liquid from the manifold 22 to the tip of the slot, and discharges the coating liquid from the opening 24A at the tip of the slot die 18 so that the slot 24 is interposed between the slot die 18 and the web 14. The bead 20 is installed. The slot 24 usually has an opening width of about 0.01 to 0.5 mm, and has a length larger than the coating width of the coating liquid on the web 14 in the web width direction (longitudinal direction). The flow path length of the slot 24 extending from the manifold 22 toward the web 14 can be set in consideration of various conditions such as the liquid composition of the coating liquid, physical properties, supply flow rate, supply liquid pressure, and the like. It is preferable to set the flow path length of the slot 24 so that the coating liquid discharged from the opening 24A has a substantially uniform flow rate and fluid pressure in the web width direction.

  A decompression chamber 26 for decompressing the web upstream side of the bead 20 is provided below the tip end portion of the slot die 18 having the above-described configuration, as shown in FIG. The decompression chamber 26 includes a back plate 26A, a side plate 26B, a rear plate 26C, and a bottom plate 26D that form a space therein, and has a box shape that maintains a decompressed state.

  The back plate 26 </ b> A is located on the most upstream side in the web conveyance direction in the decompression chamber 26, and is disposed along the width direction of the web 14. The side plate 26 </ b> B is disposed so as to be perpendicular to the back plate 26 </ b> A to constitute both side walls of the decompression chamber 26, and an edge portion (not shown) adjacent to the backup roller 12 has substantially the same curvature as the backup roller 12. The rear plate 26C is disposed below the slot die 18 and substantially parallel to the back plate 26A. The bottom plate 26D constitutes the bottom portion of the decompression chamber 26 and is joined to the back plate 26A, the side plate 26B, and the rear plate 26C at the edge portion. A gap of a predetermined size exists in each of “between the back plate 26A and the web 14” and “between the side plate 26B and the web 14”. A suction port 40 is formed in the back plate 26 </ b> A, and an air pipe 28 is connected to the suction port 40.

  The decompression chamber 26 is connected to the blower 30 through a suction port 40 and an air pipe 28, and a valve 32 and a buffer device 34 are provided in the middle of the air pipe 28. The blower 30 sucks the inside of the decompression chamber 26 through the suction port 40 and the air pipe 28 to make the inside of the decompression chamber 26 have a negative pressure. The valve 32 adjusts the degree of decompression in the decompression chamber 26 according to the opening degree. The buffer device 34 serves as a buffer unit for reducing the pressure fluctuation in the decompression chamber 26.

  A pressure gauge 36 for measuring the pressure in the decompression chamber 26 is provided in the decompression chamber 26, and the measurement result of the pressure gauge 36 is sent to the controller 38. The controller 38 adjusts the opening degree of the valve 32 based on the measurement result of the pressure gauge 36, and maintains the pressure in the decompression chamber 26 at a predetermined pressure. In the present embodiment, “pressure in the decompression chamber 26” corresponds to “pressure upstream of the web of the bead 20”.

  In addition, the web 14 and the coating liquid containing various components according to the purpose can be used. As an example, polyethylene terephthalate, polyethylene-2,6-naphthalate, cellulose diacetate, cellulose triacetate, cellulose acetate propionate, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyimide, polyamide and other known plastic films, paper, On the surface of a strip-shaped substrate such as various laminated papers coated with α-polyolefins having 2 to 10 carbon atoms, such as polyethylene, polypropylene, ethylene butene copolymer, etc. on paper, metal foils such as aluminum, copper, tin, etc. As the material of the web 14, a material in which a preliminary processed layer is formed, another flexible member, or various composite materials obtained by laminating these members can be used.

  As the solvent for the coating solution, water, various halogenated hydrocarbons, alcohols, ethers, esters, ketones, or the like can be used alone or in combination.

  In addition, as a coating solution, an optical compensation sheet coating solution, an antireflection film coating solution, an antiglare providing liquid, a magnetic coating solution, a photographic photosensitive coating solution, a magnetic coating solution, a viewing angle widening coating solution, a surface protection solution, an antistatic solution. Further, a lubricating coating solution, a color filter pigment solution, or other optical film coating solution can be used.

  In addition, as suggested in [Example] described below, as a coating liquid to be discharged from the slot die 18 toward the web 14, “a coating liquid having a surface tension of 30 mN / m or less” or “a width regulating plate 60. It is preferable to use a coating solution having a contact angle with respect to 30 ° or more.

  As shown in FIG. 2, the width regulating plates 60 are inserted into both ends of the slot 24 in the web width direction in contact with the upstream die block 18A and the downstream die block 18B constituting the wall of the slot 24. Has been. Although details will be described later (see FIG. 3), the width regulating plate 60 is a member that regulates the coating width of the coating liquid discharged from the opening 24A of the slot 24 of the slot die 18.

  The width regulating plate 60 employs a specific material or surface treatment from the viewpoint of stabilizing the application state of the coating liquid in the vicinity of the width regulating plate 60, as suggested in [Example] described below. The wettability of the coating solution is preferably adjusted. For example, the width regulating plate 60 is formed of a material such as Teflon or Newlite, or a metal plate coated with a polymer such as a fluororesin is used as the width regulating plate 60, so that the width regulating plate 60 contacts the coating liquid. It is preferable to adjust the angle to be 30 degrees or more.

  Next, the width regulating plate 60 will be described. As a result of earnest research, the present inventor has obtained the following findings as suggested in [Examples] described below.

  That is, the front end surface (hereinafter also referred to as “width control member front end surface”) 62 of the width regulating plate 60 is set so as to be substantially continuous with the upstream lip land 16A and is substantially continuous with the downstream lip land 16B. By setting, it is possible to effectively prevent the coating liquid from flowing around the width regulating plate 60.

  In particular, when the slot die 18 and the width restricting plate 60 are set to the following conditions, the present inventor has found that the coating liquid can be effectively prevented from entering around the width restricting plate 60. That is, the width-regulating upstream lip edge, which is the end portion on the width-regulating plate 60 side of the upstream lip land 16A, is the upstream lip of the width-regulating member front end face 62 with respect to the coating liquid discharge direction (see arrow A). It is preferable to adjust so as to be equal to or protrude from the upstream lip side width regulating edge which is the end portion on the land 16A side. Then, the distance between the upstream lip side width regulating edge 64 and the width regulating side upstream lip edge is set to a range of 0 μm or more and 10 μm or less, and the width regulating side which is the end portion on the width regulating plate 60 side of the downstream lip land 16B. It is preferable to set the distance between the downstream lip edge and the downstream lip side width regulating edge, which is the end portion on the downstream lip land 16B side, of the width regulating member front end face 62 within a range of 0 μm to 10 μm.

  Furthermore, the width regulating member front end surface 62 is set so as not to protrude from the downstream lip land 16B and to be retracted from the upstream lip land 16A in the discharge direction of the coating liquid (see arrow A). Is also preferable. Below, an example of suitable embodiment which this inventor pinpointed is demonstrated.

  FIG. 3 is a view showing an example of the arrangement relationship between the slot die 18 and the width restricting plate 60 of the present embodiment, and shows a state in which the tip portions of the slot die 18 and the width restricting plate 60 are viewed from the side. In the example shown in FIG. 3, the upstream side lip edge 16 </ b> A of the upstream side lip land 16 </ b> A corresponds to the upstream side lip side width regulating edge of the width regulating member front end surface 62 with respect to the discharge direction of the coating liquid (see arrow A in FIG. 3). 64 so that the position is equivalent to 64. Similarly, the width regulating side downstream lip edge 17B of the downstream lip land 16B is at the same position as the downstream lip side width regulating edge 66 of the width regulating member front end face 62 with respect to the discharge direction of the coating liquid (see arrow A). It is provided as follows.

  Accordingly, the upstream lip land 16A and the width regulating member front end surface 62 are adjusted so that the distance between the width regulating upstream lip edge 17A and the upstream lip side width regulating edge 64 becomes 0 μm. Further, the downstream lip land 16B and the width regulating member front end surface 62 are adjusted so that the distance between the width regulating downstream lip edge 17B and the downstream lip side width regulating edge 66 is 0 μm. The front end surface 62 of the width regulating member has a planar structure including an upstream lip side width regulating edge 64 and a downstream lip side width regulating edge 66, and the downstream lip land with respect to the discharge direction of the coating liquid (see arrow A). It has a shape that does not protrude from 16B (see the dotted line portion B in FIG. 3) and does not retract from the upstream lip land 16A (see the dotted line portion C in FIG. 3).

  In this way, the width regulating member front end surface 62 is set so as to be substantially continuous with the upstream lip land 16A and the downstream lip land 16B, so that the coating liquid wraps around the front end portion of the width regulating plate 60 very effectively. Can be prevented. Thereby, it is possible to avoid the coating liquid from staying at the end in the web width direction of the slot die 18 provided with the width regulating plate 60, and the bead 20 (coating liquid) in the vicinity of the width regulating plate 60. The edge portion can be stabilized. Therefore, the coating liquid discharged from the vicinity of the width regulating plate 60 is also stably applied to the web 14, and a good quality coating film (coating layer) is generated on the web 14. And it becomes possible to manufacture the optical film etc. which require high manufacture precision using such a coating film.

  The above-described matters exemplify one aspect of the present invention, and various modifications such as design changes can be added based on the knowledge of those skilled in the art, and known elements can be applied. Such various aspects can also be included in the scope of the present invention.

For example, the width restricting plate 60 is not limited to that shown in FIG. A width having a flat or curved width regulating member front end face 62 that substantially connects the "width regulating side upstream lip edge 17A of the upstream lip land 16A" and the "width regulating side downstream lip edge 17B of the downstream lip land 16B". The restriction plate 60 can be preferably used. For example, as shown in FIG. 4, the upstream lip side width restricting edge 64 of the width restricting plate 60 protrudes from the width restricting side upstream lip edge 17A of the upstream lip land 16A to satisfy the following expression (1). in the range, the distance D _a between the upstream lip width limiting edge 64 and the width regulating side upstream lip edge 17A can be appropriately adjusted.

0 μm ≦ D _A ≦ 10 μm Formula (1)
Further, as shown in FIG. 5, the downstream lip side width regulating edge 66 of the width regulating plate 60 is retracted from the width regulating side downstream lip edge 17B of the downstream lip land 16B to satisfy the following formula (2). range, it is possible to appropriately adjust the distance D _B1 of the downstream lip width limiting edge 66 and the width regulating side downstream lip edge 17B.

0 μm ≦ D _B1 ≦ 10 μm Formula (2)
Further, as shown in FIG. 6, the downstream lip side width restricting edge 66 of the width restricting plate 60 is protruded from the width restricting side downstream lip edge 17B of the downstream lip land 16B to satisfy the following expression (3). range, it is possible to appropriately adjust the distance D _B2 of the downstream lip width limiting edge 66 and the width regulating side downstream lip edge 17B.

0 μm ≦ D _B2 ≦ 10 μm Formula (3)
Further, as shown in FIG. 7, the downstream lip side width regulating edge 66 of the width regulating plate 60 is retracted from the width regulating side downstream lip edge 17B of the downstream lip land 16B, and the upstream lip side of the width regulating plate 60 The width restricting edge 64 may protrude beyond the width restricting upstream lip edge 17A of the upstream lip land 16A. In that case, the above equation (1) and to satisfy equation (2), the distance D _A and the downstream lip width limiting edge 66 and the width regulating the upstream lip width limiting edge 64 and the width regulating side upstream lip edge 17A it is preferable to appropriately adjust the distance D _B1 of the side downstream lip edge 17B.

Also, as shown in FIG. 8, the downstream lip side width regulating edge 66 of the width regulating plate 60 protrudes from the width regulating side downstream lip edge 17B of the downstream lip land 16B, and the upstream lip side of the width regulating plate 60 The width restricting edge 64 may protrude beyond the width restricting upstream lip edge 17A of the upstream lip land 16A. In that case, the above equation (1) and to satisfy equation (3), the distance D _A and the downstream lip width limiting edge 66 and the width regulating the upstream lip width limiting edge 64 and the width regulating side upstream lip edge 17A it is preferable to appropriately adjust the distance D _B2 of the side downstream lip edge 17B.

  Further, as shown in FIGS. 9 to 11, the width regulating member front end surface 62 of the width regulating plate 60 is downstream of the downstream side lip land 16B of the width regulating member front end surface 62 with respect to the direction perpendicular to the downstream side lip land 16B. The upstream side lip land 16A side of the front end surface 62 of the width regulating member with respect to the direction perpendicular to the upstream side lip land 16A It is possible to adopt various shapes in a range that is not retracted from the upstream lip side width restricting edge 64 that is the end portion (see the dotted line portion C). For example, an arc shape in which “the curvature of the upstream lip land 16A at the width regulating side upstream lip edge 17A” and “the curvature of the width regulating member front end face 62 at the upstream lip side width regulating edge 64” are substantially equal (see FIG. 9), An arc shape (see FIG. 10) in which “the curvature of the downstream lip land 16B at the width regulating downstream lip edge 17B” and “the curvature of the width regulating member front end face 62 at the downstream lip side width regulating edge 66” are substantially equal. It is possible to set the width regulating member front end face 62 to a shape (see FIG. 11) that combines 9 and FIG.

  Further, the backup roller 12, the slot die 18, and the decompression chamber 26 in the slot die coater type coating system 10 may have any arrangement relationship as long as the coating liquid can be properly coated on the web 14. For example, the discharge angle of the coating liquid of the slot die 18 with respect to the web 14, the cross-sectional shape of the manifold 22, the winding state of the web 14 with respect to the backup roller 12, the winding portion of the web 14 with respect to the backup roller 12, the slot die 18 and the decompression chamber 26. The relative positional relationship, the overbite amount, and the like can be appropriately adjusted according to the purpose.

  Although the Example using the above-mentioned slot die coater type coating system 10 is described below, the present invention is not limited to the following examples.

(Common application conditions)
The coating solution used in each of the following examples (excluding Example 3) was prepared as follows. That is, “200 g of methylisoptyl ketone” is added to “200 g of thermally crosslinkable fluorine-containing polymer having a refractive index of 1.46 (JN-7221, manufactured by JSR Corporation)” and stirred. And the solution for low refractive index layers prepared by filtering the stirred solution with the polypropylene filter (PPE-01) with a hole diameter of 1 micrometer was used as a coating liquid.

  Table 1 below shows common application conditions in each example. Each example was performed according to the coating conditions shown in Table 1 unless otherwise specified.

表１に示されているように共通の塗布条件は、ウェブ１４の搬送速度を示す塗布速度が６０ｍ／ｍｉｎ、ウェブ１４上の塗布膜の膜厚を示す塗布膜厚が５ｍｌ／ｍ^２、ウェブ１４上の塗布膜の幅を示す塗布幅が６００ｍｍ、下流側リップランド部１６Ｂとウェブ１４との間隔を示す下流側リップ間隙が５０μｍ、オーバーバイト量が５０μｍ、ウェブ１４の走行方向に関する上流側リップランド１６Ａの長さを示す上流側リップ長が２００μｍ、ウェブ１４の走行方向に関する下流側リップランド１６Ｂの長さを示す下流側リップ長が２００μｍ、ウェブ１４の走行方向に関するスロット幅が２００μｍ、幅規制板６０の材質がＳＵＳ６３０、ウェブ１４の走行方向に関する幅規制板６０の幅が１９５μｍ、塗布液の表面張力が２０ｍＮ／ｍ、減圧チャンバー２６による減圧度が１．０ｋＰａ、上下リップ先端面の真直度が塗布幅１ｍ当たり５μｍ、となっている。

As shown in Table 1, the common coating conditions are that the coating speed indicating the conveyance speed of the web 14 is 60 m / min, the coating film thickness indicating the film thickness of the coating film on the web 14 is 5 ml / m ² , and the web 14 is a coating width indicating the width of the coating film on the substrate 14, a downstream lip gap indicating the distance between the downstream lip land portion 16 </ b> B and the web 14 is 50 μm, an overbite amount is 50 μm, and an upstream lip in the running direction of the web 14. The upstream lip length indicating the length of the land 16A is 200 μm, the downstream lip length indicating the length of the downstream lip land 16B in the traveling direction of the web 14 is 200 μm, the slot width in the traveling direction of the web 14 is 200 μm, and the width restriction The material of the plate 60 is SUS630, the width of the width regulating plate 60 in the running direction of the web 14 is 195 μm, the surface tension of the coating liquid is 20 mN / m, Vacuum degree of pressure chamber 26 is 1.0 kPa, straightness of the upper and lower lip end surface becomes coated width 1m per 5 [mu] m, and.

  Further, the width regulating plate 60 is observed from the upstream side and the downstream side in the upstream lip land surface direction, the downstream side in the downstream lip land surface direction, and from the die side surface by the microscope (VHX-200). The position is adjusted by observing and measuring the amount of protrusion. The measurement with a microscope can measure the distance at ± 0.1 μm.

Example 1
In this example, the protruding state (retracted state) of the width regulating plate 60 with respect to the tip of the slot die 18 was changed, and the coating liquid was discharged from the slot die 18. FIG. 12 shows the slot die 18 and the width regulating plate 60 used in Example 1, and the application result of the coating liquid. In FIG. 12, in (a), the width regulating member front end face 62 is disposed at a position protruding by 25 μm from the downstream lip land 16B, and in (b), the intermediate between the upstream lip land 16A and the downstream lip land 16B. The width regulating member front end surface 62 is disposed at a position protruding by 25 μm from the upstream side lip land 16A. In (c), the end (edge) of the width regulating member front end surface 62 is connected to the upstream side lip land 16A and The end portion (edge) of the downstream lip land 16B is substantially matched, and the width regulating member front end face 62 is disposed so as to be substantially continuous with the upstream lip land 16A and the downstream lip land 16B (see FIG. 3). In d), the width regulating member front end face 62 is disposed at a position retracted by 25 μm from the upstream lip land 16A.

  In FIG. 12, “◯” indicates that the bead 20 is established, and the width fluctuation in the width direction of the coating film on the web 14 (hereinafter also referred to as “coating film edge”) in the web width direction is ± 1 mm. “△” indicates that the bead 20 is established, and the runout in the web width direction of the coating film edge is less than ± 3 mm, and “x” indicates that the bead 20 is not established. Alternatively, it indicates that the width fluctuation in the web width direction of the coating film edge is ± 3 mm or more.

  As shown in FIG. 12, from the viewpoint of performing stable application of the coating liquid while suppressing the width fluctuation of the coating film edge, the “upstream lip land 16A and the downstream lip land 16B are substantially the same as those in (c)”. It is preferable to arrange the width regulating member front end face 62 so as to be continuous.

(Example 2)
In this example, the amount of protrusion (retraction amount) of the width regulating plate 60 with respect to the tip end portion of the slot die 18 was changed, and the coating liquid was discharged from the slot die 18. Table 2 below shows the protrusion amount (retraction amount) of the width restricting plate 60 (width restricting member front end face 62) with respect to the upstream lip land 16A and the downstream lip land 16B, and the application result of the coating liquid.

表２において、「下流側」は、下流側リップランド１６Ｂに対する幅規制板６０（幅規制部材先端面６２）の突出量を示し、「上流側」は、上流側リップランド１６Ａに対する幅規制板６０（幅規制部材先端面６２）の突出量を示す。「上流側」および「下流側」の欄における「０」は、上流側リップランド１６Ａあるいは下流側リップランド１６Ｂの位置を示し、「＋」は、幅規制板６０（幅規制部材先端面６２）が塗布液の吐出方向へ上流側リップランド１６Ａあるいは下流側リップランド１６Ｂよりも突出していることを示し、「−」は、幅規制板６０（幅規制部材先端面６２）が、塗布液の吐出方向とは逆方向へ、上流側リップランド１６Ａあるいは下流側リップランド１６Ｂよりも引っ込んでいることを示す。また、「◎」は、ビード２０が成立し、塗布膜エッジのウェブ幅方向への幅振れが±０．５ｍｍ未満であることを示し、「○」、「△」、および「×」は、上述した図１２の場合と同様の内容を示す。

In Table 2, “downstream” indicates the protruding amount of the width restricting plate 60 (width restricting member front end face 62) with respect to the downstream lip land 16B, and “upstream” indicates the width restricting plate 60 with respect to the upstream lip land 16A. The protrusion amount of (width regulating member front end face 62) is shown. “0” in the “upstream side” and “downstream side” columns indicates the position of the upstream lip land 16A or the downstream lip land 16B, and “+” indicates the width regulating plate 60 (width regulating member front end surface 62). Indicates that it protrudes from the upstream lip land 16A or the downstream lip land 16B in the discharge direction of the coating liquid, and “−” indicates that the width regulating plate 60 (width regulating member front end face 62) ejects the coating liquid. It shows that it is retracted from the upstream lip land 16A or the downstream lip land 16B in the direction opposite to the direction. In addition, “ビ ー” indicates that the bead 20 is established, and the width fluctuation in the web width direction of the coating film edge is less than ± 0.5 mm, and “◯”, “Δ”, and “×” The same content as the case of FIG. 12 mentioned above is shown.

  As shown in Table 2, from the viewpoint of stably applying the coating liquid while suppressing the width fluctuation of the coating film edge, the width regulating plate 60 (width regulating member front end face 62) with respect to the downstream lip land 16B. Is preferably set in the range of “−10 μm to +10 μm”. Similarly, the protrusion amount (retraction amount) of the width restricting plate 60 (width restricting member front end face 62) with respect to the upstream side lip land 16A is preferably set in a range of “0 μm to +10 μm”. When the protruding amount (retraction amount) of the width restricting plate 60 (width restricting member front end face 62) with respect to the upstream lip land 16A and the downstream lip land 16B deviates from the above preferable range, It was confirmed that the bead 20 became unstable and the coating state of the coating liquid became unstable.

(Example 3)
In this example, the surface tension of the coating solution was changed and the coating solution was discharged from the slot die 18. Since it is difficult to change the surface tension with an organic solvent-based coating solution, in this example, a solution in which the surface tension was adjusted by adjusting the mixing amount of water, ethanol, and dye was used as the coating solution. The dye used in this example was 4,4 ′-(1,3-pentadien-1-yl-5-ylidene) -bis [3-carboethoxy-1- (p- Sulfo-phenyl) -5-pyrazolone] dipotassium salt of 4,4 '-(1,3-pentadien-1-yl-5-ylidene) -bis [3-carboethoxy-1- (p- sulfo-phenyl) -5-pyrazolone]) was used.

以下の表３は、塗布液の表面張力と、塗布液の塗布結果とを示す。

Table 3 below shows the surface tension of the coating solution and the coating result of the coating solution.

表３において、「（ｂ）」および「（ｃ）」は、図１２の「（ｂ）」および「（ｃ）」に準じており（実施例１参照）、塗布液の表面張力以外の塗布条件は図１２の「（ｂ）」および「（ｃ）」と同様である。また、「◎」、「○」、「△」、および「×」は、上述の図１２および表２におけるのと同様の内容を示す。

In Table 3, “(b)” and “(c)” are in accordance with “(b)” and “(c)” of FIG. 12 (see Example 1), and coating other than the surface tension of the coating solution. The conditions are the same as “(b)” and “(c)” in FIG. In addition, “」 ”,“ ◯ ”,“ Δ ”, and“ × ”indicate the same contents as in FIG. 12 and Table 2 described above.

  As shown in Table 3, from the viewpoint of carrying out a stable coating liquid application by suppressing the width fluctuation of the coating film edge, this is particularly true when using a coating liquid having a surface tension of 30 mN / m or less. It was confirmed that the slot die 18 and the width regulating plate 60 (see (c) of Table 3) according to the invention are effective. This is because the coating solution bead 20 having a surface tension greater than 30 mN / m is inherently high in stability, and the tip shape of the width regulating plate 60 is applied when a coating solution having a surface tension of 30 mN / m or less is used. This is thought to be due to the large influence on the application of the liquid.

Example 4
In this example, the wettability of the width regulating plate 60 with respect to the coating liquid was changed, and the coating liquid was discharged from the slot die 18 shown in FIG. Specifically, the contact angle is used as an indicator of the wettability of the width restricting plate 60 to the coating liquid, and the material of the surface of the width restricting plate 60 is changed to “SUS”, “Teflon”, and “New Light” to thereby restrict the width. The contact angle of the plate 60 with respect to the coating solution was adjusted. “SUS” means stainless steel (Stainless Used Steel), “Teflon” means tetrafluoroethylene, and “Newlite” means an average molecular weight of more than 5.5 million (measured by light scattering method) produced by the Ziegler method. Of ultra high molecular weight polyethylene. Table 4 below shows the material of the width regulating plate 60, the contact angle, and the application result of the coating liquid.

表４において、「◎」、「○」、「△」、および「×」は、上述の図１２および表２の場合と同様の内容を示す。

In Table 4, “◎”, “◯”, “Δ”, and “×” indicate the same contents as those in FIG. 12 and Table 2 described above.

  As shown in Table 4, from the viewpoint of performing stable coating liquid application by suppressing the width fluctuation of the coating film edge, when the contact angle is increased to make it difficult to wet, particularly with respect to the width regulating plate 60. When the contact angle of the coating liquid is adjusted to 30 ° or more (see “Teflon” and “New Light” in Table 4), the slot die 18 and the width regulating plate 60 (see FIG. 12C) according to the present invention are provided. It was confirmed to be effective.

  Note that the wettability of the width regulating plate 60 to the coating liquid is determined by the material of the width regulating plate 60 in contact with the coating liquid, so that at least the coating liquid of the width regulating plate 60 made of, for example, a metal plate is used. It is also possible to use a width regulating plate 60 in which the contact portion is coated with a polymer such as a fluororesin and the contact angle is adjusted to 30 degrees or more. Further, the “wetting property of the width regulating plate 60 with respect to the coating solution” in the vicinity of the opening 24A at the tip end portion of the slot die 18 is particularly important for the coating state of the coating solution. Therefore, it is considered that the application stability of the coating liquid can be improved if the portion of the width regulating plate 60 near the opening 24A of the slot 24 is coated with a fluororesin or the like.

It is a block diagram of the slot die coater in one embodiment of this invention. It is a perspective view which shows the state which cut | disconnected some slot dies. It is a figure which shows an example of arrangement | positioning relationship of a slot die and a width control board, and is a figure which shows the state which looked at the front-end | tip part of the slot die and the width control board from the side. It is a figure which shows the modification of a width control board. It is a figure which shows the modification of a width control board. It is a figure which shows the modification of a width control board. It is a figure which shows the modification of a width control board. It is a figure which shows the modification of a width control board. It is a figure which shows the modification of a width control board. It is a figure which shows the modification of a width control board. It is a figure which shows the modification of a width control board. It is a figure which shows the slot die and width control board which were used in Example 1, and the application result of a coating liquid. It is a figure which shows an example of the typical arrangement | positioning relationship of the slot die of an over bite structure, and a width control board, and is a figure which shows the state which looked at the front-end | tip part of the slot die and the width control board from the side. It is a figure which shows the other example of the typical arrangement | positioning relationship of the slot die of an over bite structure, and a width control board. It is a figure which shows the other example of the typical arrangement | positioning relationship of the slot die of an over bite structure, and a width control board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Slot die coater, 12 ... Backup roller, 14 ... Web, 16 ... Lip land, 16A ... Upstream lip land, 16B ... Downstream lip land, 17A ... Width Restriction side upstream lip edge, 17B ... Width restriction side downstream lip edge, 18 ... Slot die, 18A ... Upstream die block, 18B ... Downstream die block, 20 ... Bead, 22. ..Manifold 24 ... slot 24A ... opening 26 ... depressurization chamber 26A ... back plate 26B ... side plate 26C ... rear plate 26D ... bottom Plate, 28 ... Air piping, 30 ... Blower, 32 ... Valve, 34 ... Buffer device, 36 ... Pressure gauge, 38 ... Control 40 ... suction port, 42 ... coating liquid pump, 44 ... coating liquid tank, 46 ... coating liquid supply pipe, 50 ... main body, 52 ... coating liquid discharge pipe, 54 ... ··· Closing plate, 60 ... Width regulating plate, 62 ... Width regulating member front end surface, 64 ... Upstream lip side width regulating edge, 66 ... Downstream lip side width regulating edge

Claims (7)

The coating liquid is discharged from the slot of the slot die toward the surface of the support that continuously runs while being supported by the backup roller, and the support of the bead of the coating liquid that is installed between the slot die and the support is supported. In the coating liquid coating method, the body upstream side is decompressed by a decompression chamber, and the coating liquid is coated on the surface of the support by the bead.
Of the tip surface of the slot die, the downstream die tip surface downstream of the slot is disposed at a position closer to the support than the upstream upstream die tip surface,
A width regulating member that regulates the coating width of the coating liquid discharged from the slot toward the support is inserted into the slot,
The front end surface of the width regulating member is substantially continuous with the upstream die front end surface and substantially downstream with the downstream die front end surface, and is provided non-parallel to the upstream die front end surface and the downstream die front end surface,
The distance between the upstream end of die tip side of the width regulating member and the support is much larger than the distance between the end portion of the downstream die tip side of the width regulating member and the support member,
The distance between the end of the upstream die front end surface on the width regulating member side and the end of the front end surface of the width regulating member on the upstream die front end surface side is 10 μm or less; The distance between the end on the width regulating member side and the end on the downstream die tip surface side of the tip surface of the width regulating member is 0 μm or more and 10 μm or less, and the upstream die tip surface side of the width regulating member The end portion of the upstream die protrudes beyond the end portion on the width regulating member side of the upstream die front end surface . The front end surface of the width regulating member does not protrude from the end of the front end surface of the width regulating member on the downstream die front end side with respect to the direction perpendicular to the downstream die front end surface. 2. The coating liquid coating method according to claim 1, wherein the tip of the width regulating member is not retracted with respect to a direction perpendicular to the front end surface from an end of the upstream die front end side. The coating liquid coating method according to claim 1 or 2, wherein the coating liquid has a surface tension of 30 mN / m or less. The coating liquid coating method according to claim 1, wherein a contact angle of the coating liquid with respect to the width regulating member is 30 degrees or more. 5. The coating liquid coating method according to claim 1, wherein at least a portion of the width regulating member that contacts the coating liquid is coated with a polymer. The manufacturing method of the optical film characterized by including the process of forming at least 1 layer of the coating layer obtained by the coating method of the coating liquid of any one of the said Claims 1-5. The coating liquid is discharged from the slot of the slot die toward the surface of the support that continuously runs while being supported by the backup roller, and the support of the bead of the coating liquid that is installed between the slot die and the support is supported. In the coating liquid coating apparatus for decompressing the body upstream side by a decompression chamber and coating the coating liquid on the surface of the support by the bead,
Of the tip surface of the slot die, the downstream die tip surface downstream of the slot is disposed at a position closer to the support than the upstream upstream die tip surface,
A width regulating member that regulates the coating width of the coating liquid discharged from the slot toward the support is inserted into the slot,
The front end surface of the width regulating member is substantially continuous with the upstream die front end surface and substantially downstream with the downstream die front end surface, and is provided non-parallel to the upstream die front end surface and the downstream die front end surface,
The distance between the end on the upstream die tip surface side of the width restricting member and the support is larger than the distance between the end on the downstream die tip surface side of the width restricting member and the support.
The distance between the end of the upstream die front end surface on the width regulating member side and the end of the front end surface of the width regulating member on the upstream die front end surface side is 10 μm or less; The distance between the end on the width regulating member side and the end on the downstream die tip surface side of the tip surface of the width regulating member is 0 μm or more and 10 μm or less, and the upstream die tip surface side of the width regulating member The coating liquid coating apparatus is characterized in that the end portion of the upstream die protrudes beyond the end portion of the upstream die front end surface on the width regulating member side.

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