JP5157486B2 - Die head and die coater provided with the same - Google Patents

Description

  The present invention relates to a die head for applying a coating solution to a substrate and a die coater including the same.

In the manufacturing process of the color filter for liquid crystal displays, a resist solution is applied to the glass substrate using a die coater in order to form a resist film on the glass substrate. The resist solution is introduced into a manifold inside the die head and applied through a slit connected to the manifold (see, for example, Patent Document 1).
JP-A-10-286507

  Air may be mixed in the resist solution introduced into the die head. Even if a resist solution is applied to the glass substrate in such a state, there is a possibility that it cannot be applied uniformly. Therefore, a technique for discharging air by providing an air discharge port in the manifold is well known. However, if the direction in which the air rises in the flow direction of the resist solution in the manifold, the movement of the air may be hindered, or air may stay in the vicinity of the discharge port, and the air may not be sufficiently discharged.

  Accordingly, an object of the present invention is to provide a die head capable of sufficiently discharging air in a manifold and a die coater including the die head.

In the die head of the present invention, a manifold (23) for supplying the coating liquid (R) to the slits (24, 25) is formed extending in the longitudinal direction, and an inlet (15) for introducing the coating liquid is formed at the upper end of the manifold. In the die head (3) in which the coating liquid is discharged from the slit connected to the lower end of the manifold, the upper wall surface (22e) forming the manifold is inclined in the longitudinal direction with the introduction port as the lower end. Air discharge ports (16a, 16b) for discharging air are provided at the upper end thereof, the introduction port is located at the center in the longitudinal direction of the manifold, and the air discharge port is disposed in the longitudinal direction of the manifold. The air discharge ports are located at both end sides (12a, 12b), respectively, and are located closer to the center side than the longitudinal ends of the manifolds. The upper wall surface forming the door has a downward gradient from the air discharge port toward the end portion, and the gradient of the upper wall surface forming the manifold between the air discharge port and the end portion is the introduction The cross-sectional area of the manifold when cut perpendicularly to the longitudinal direction is greater than the gradient of the upper wall surface forming the manifold between the mouth and the air discharge port, and is the same over the longitudinal direction. The above-mentioned problem is solved by being.

According to the die head of the present invention, when the coating liquid is introduced from the introduction port, the coating liquid is supplied to the slit while moving along the manifold. An air discharge port is provided at the point where the coating liquid moves, and the manifold is inclined upward from the introduction port toward the air discharge port.Therefore, the direction in which the air in the manifold rises and the direction in which the coating liquid flows Are in the same direction. Thereby, the air mixed in the coating liquid can be moved to the air discharge port without staying in the manifold. In addition, the coating liquid moves in both directions from the introduction port located at the center in the longitudinal direction of the manifold. The air in the manifold also moves toward one of the air outlets. Therefore, the coating liquid introduced from the inlet can be dispersed in both directions, and the air can be discharged while efficiently supplying the coating liquid to the slit via the manifold. Further, it is possible to easily discharge the air staying at both ends in the longitudinal direction of the manifold. Further, the flow of the coating liquid in the manifold is in one direction. Thereby, since the moving direction of the air and the moving direction of the coating liquid coincide with each other, the flow of the coating liquid assists the movement of the air and the air is easily discharged.

A manifold (23) for supplying the coating liquid (R) to the slits (24, 25) is formed extending in the longitudinal direction, and an inlet (15) for introducing the coating liquid is provided at the upper end of the manifold. In the die head (3) in which the coating liquid is discharged from the slit connected to the lower end of the manifold, the upper wall surface (22e) forming the manifold has a gradient in the longitudinal direction with the introduction port as the lower end, At the upper end, air discharge ports (16a, 16b) for discharging air are provided, and a plurality of the introduction ports and the air discharge ports are provided, and the introduction port and the air discharge port are arranged in the longitudinal direction of the manifold. Alternatively, they may be positioned alternately. According to this aspect, when the coating liquid is introduced from the inlet, the coating liquid is supplied to the slit while moving along the manifold. An air discharge port is provided at the point where the coating liquid moves, and the manifold is inclined upward from the introduction port toward the air discharge port.Therefore, the direction in which the air in the manifold rises and the direction in which the coating liquid flows Are in the same direction. Thereby, the air mixed in the coating liquid can be moved to the air discharge port without staying in the manifold. Further, the coating liquid is introduced from a plurality of introduction ports. Therefore, even if the die head is enlarged, the air can be discharged well while sufficiently maintaining the introduction pressure of the coating liquid. In this embodiment, the cross-sectional area of the manifold when cut perpendicularly to the longitudinal direction may be the same over the longitudinal direction. According to this form, the flow of the coating liquid in the manifold is unidirectional. Thereby, since the moving direction of the air and the moving direction of the coating liquid coincide with each other, the flow of the coating liquid assists the movement of the air and the air is easily discharged. Moreover, you may implement | achieve as a die coater provided with such a die head.

  Note that the present invention may be embodied as a die coater including the above-described die head.

  In addition, in the above description, in order to make an understanding of this invention easy, the reference sign of the accompanying drawing was attached in parenthesis, but this invention is not limited to the form of illustration by it.

  As described above, in the die head of the present invention and the die coater including the die head, when the coating liquid is introduced from the introduction port, the coating liquid is supplied to the slit while moving along the manifold. An air discharge port is provided at the point where the coating liquid moves, and the manifold is inclined upward from the introduction port toward the air discharge port.Therefore, the direction in which the air in the manifold rises and the direction in which the coating liquid flows Are in the same direction. Thereby, the air mixed in the coating liquid can be moved to the air discharge port without staying in the manifold.

  FIG. 1 is a perspective view showing a die coater to which a die head according to an embodiment of the present invention is applied. The die coater 1 is an apparatus for applying a resist solution as a coating solution to the glass substrate S, and is used for forming a resist film on the glass substrate S of a color filter for liquid crystal display. The die coater 1 includes a coating stage 2 for placing the glass substrate S, a die head 3 for coating the resist solution R on the glass substrate S on the coating stage 2, a die driving mechanism 4 for moving the die head 3, and a glass A priming roller 5 for optimizing the state of the die head 3 before application to the substrate S is provided. In FIG. 1, the left-right direction of the die coater 1 is shown as the X direction, and the front-back direction is shown as the Y direction. The glass substrate S is placed at a predetermined position on the coating stage 2. The die head 3 has a slit shape inside, and discharges the resist solution R from the tip portion 3a passed in the X direction. Details will be described later. The die drive mechanism 4 is provided with a holding portion 4a that holds the die head 3 and a drive portion 4b that can reciprocate the holding portion 4a in the Y direction. The holding part 4a holds the upper part of the die head 3 so that the tip part 3a that discharges the resist solution R keeps a certain distance from the glass substrate S. The drive unit 4b is configured using known techniques such as various motors and encoders, and moves the die head 3 in the Y direction by driving the holding unit 4a. In this way, the die head 3 applies the resist solution R on the glass substrate S. The priming roller 5 is for optimizing the accumulation of the resist solution R at the tip 3 a of the die head 3. The die head 3 is applied to the priming roller 5 before being applied onto the glass substrate S, whereby the pool of the resist solution R at the tip 3a is adjusted and optimized.

  FIG. 2 is an enlarged perspective view of the die head 3, and FIG. 3 is a cross-sectional view of the die head 3. The die head 3 includes a first die block 11 and a second die block 12 that constitute a main part of the die head 3, an upper plate 13 and side plates 14a and 14b for fixing the first and second die blocks 11 and 12, and a resist. An introduction port 15 for introducing the liquid R and air discharge ports 16 a and 16 b for discharging the air inside the die head 3 are provided. The first and second die blocks 11 and 12 are provided with mating surfaces 21 and 22 that are combined with each other. The mating surface 21 of the first die block 11 is a flat surface. On the other hand, the mating surface 22 of the second die block 12 has a contact surface 22a that contacts the mating surface 21, a manifold forming surface 22b, a first slit forming surface 22c, and a second slit forming surface 22d. It is formed over the longitudinal direction of the die head 3. The contact surface 22a is a flat surface and comes into contact with the mating surface 21 at a corresponding position when the mating surfaces 21 and 22 are combined. The manifold forming surface 22b recedes into a semi-cylindrical shape as compared with the contact surface 22a, and forms a manifold 23 when combined with the corresponding mating surface 21. A first slit forming surface 22c is formed adjacent to the lower end of the manifold forming surface 22b, and a second slit forming surface 22d is formed adjacent to the lower end of the first slit forming surface 22c. The first slit forming surface 22c and the second slit forming surface 22d are surfaces that are receded in parallel as compared with the contact surface 22a, and when combined with the corresponding mating surface 21, the first slit 24 and the second slit as the slit, respectively. A slit 25 is formed. The gap g2 of the second slit 25 is smaller than the gap g1 of the first slit 24, and the second slit 25 reaches the tip 3a.

  The upper plate 13 supports and fixes the upper surfaces of the first and second die blocks 11 and 12 in which the mating surfaces 21 and 22 are combined with each other. The side plates 14 a and 14 b support and fix both ends of the first and second die blocks 11 and 12 fixed by the upper plate 13. The introduction port 15 and the air discharge ports 16a and 16b are provided along the mating surfaces 21 and 22 on the upper surfaces of the first and second die blocks 11 and 12, and are connected to the upper end of the manifold forming surface 22b. That is, by providing a recess for forming a passage when the first and second die blocks 11 and 12 are combined in each or one of the mating surfaces 21 and 22, the introduction port 15 and the air exhaust at each position. Outlets 16a and 16b are formed. The introduction port 15 is connected to a tank (not shown) that stores the resist solution R, and introduces the resist solution R that is sent using various known pumps into the manifold 23. The air discharge ports 16a and 16b are piped to a drain tank (not shown) via an air vent, and discharge air present in the manifold 23 and the first and second slits 24 and 25. The upper plate 13 may be piped by forming a through hole at a position corresponding to the inlet 15 and the air outlets 16a and 16b. Here, the air means air bubbles mixed in the introduced resist solution R, air existing in the manifold 23 before introducing the resist solution R, and the like.

  FIG. 4 is a perspective view showing the mating surface 22 of the second die block 12. The upper wall surface 22e of the manifold forming surface 22b has a gradient with the inlet 15 as the lower end and the air discharge ports 16a and 16b as the upper ends. That is, since the manifold 23 is formed so as to incline upward from the introduction port 15 toward the air discharge ports 16a and 16b, the moving direction of the resist solution R is upward. The cross-sectional area of the manifold 23 when cut perpendicular to the longitudinal direction of the die head 3 is the same over the longitudinal direction. As a result, the flow of the resist solution R in the manifold 23 is in one direction. Further, the upper wall surface 22e of the manifold forming surface 22b1 between the end portion 12a of the second die block 12 and the air discharge port 16a and between the other end portion 12b and the air discharge port 16b also has a gradient. The upper wall surface 22e of the manifold forming surface 22b1 is inclined upward from the end portions 12a, 12b toward the air discharge ports 16a, 16b. The gradient of the upper wall surface 22e of the manifold forming surface 22b1 is larger than the gradient of the upper wall surface 22e of the manifold forming surface 22b2 between the introduction port 15 and the air discharge ports 16a and 16b. Thereby, the air staying at the end portions 12a and 12b can be easily discharged.

  The operation of the die head 3 will be described with reference to FIG. When the resist solution R is introduced into the manifold 23 from the introduction port 15, the resist solution R moves in the manifold 23 in the direction of the arrow A shown by the solid line in FIG. That is, the resist solution R moves to both ends along the manifold 23, and the resist solution R spreads in the longitudinal direction of the die head 3. The resist solution R moves from the manifold 23 to the second slit 25 via the first slit 24 by the introduction pressure of the resist solution R, and is discharged from the tip portion 3a.

  When air is mixed in the resist solution R introduced into the manifold 23 from the introduction port 15, the air moves in the manifold 23 in the direction of the arrow B indicated by the broken line in FIG. 4, that is, in the same direction as the resist solution R. . This is because the manifold 23 is formed to be inclined upward. For this reason, air moves without staying in the manifold 23, reaches the air discharge ports 16a and 16b, and is discharged. Further, even if the air is pushed by the flow of the resist solution R and the air moves to the first slit 24 and the second slit 25, it moves along the inclination of the upper wall surface 22 e of the manifold 23 if it joins the manifold 23 by buoyancy. It reaches the air discharge ports 16a and 16b.

  The present invention is not limited to the above-described form and can be implemented in various forms. For example, in this embodiment, the introduction port 15 is disposed at the center and the air discharge ports 16a and 16b are disposed at both ends, and the manifold 23 is configured to have a V shape. However, the present invention is not limited thereto. However, for example, the introduction port may be disposed on one end side of the die head 3 and one air discharge port may be provided on the other end side. If the manifold is configured to incline upward from the introduction port toward the air discharge port, the moving direction of the resist solution R and the moving direction of the air are the same, and no air stays. For the same reason, a plurality of inlets and air outlets may be arranged alternately. Even when the die head 3 is enlarged, the resist solution can be introduced into the manifold 23 from a plurality of locations, and the introduction pressure of the resist solution R can be maintained. The air discharge ports 16 a and 16 b may be provided at the end portions 12 a and 12 b of the second die block 12.

  In the present embodiment, the manifold 23 has been described as a semi-cylindrical shape formed by the manifold forming surface 22b1 and the mating surface 21, but the present invention is not limited to this. For example, the mating surface 21 is provided with a curved surface similar to the manifold forming surface 22b1. These may be combined into a cylindrical shape or a polygonal shape. The upper wall surface 22e only needs to be inclined upward toward the air discharge ports 16a and 16b, and the manifold 23 may be provided in an appropriate shape. In this embodiment, the resist solution is described as an example of the coating solution. However, the present invention is not limited to this. Also good.

1 is a perspective view showing a die coater to which a die head according to one embodiment of the present invention is applied. The expansion perspective view of a die head. Sectional drawing of a die head. The perspective view which shows the mating surface of a 2nd die block.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Die coater 3 Die head 15 Inlet port 16a, 16b Air exhaust port 23 Manifold 24 First slit (slit)
25 Second slit (slit)
22e Upper wall surface R Resist liquid (coating liquid)

Claims (2)

A manifold for supplying the coating liquid to the slit is formed to extend in the longitudinal direction. An inlet for introducing the coating liquid is provided at the upper end of the manifold, and the coating liquid is discharged from the slit connected to the lower end of the manifold. In the die head
The upper wall surface forming the manifold has a gradient in the longitudinal direction with the introduction port as a lower end, and an air discharge port for discharging air is provided at the upper end .
The introduction port is located at the center in the longitudinal direction of the manifold, and the air discharge ports are located at both ends in the longitudinal direction of the manifold,
The air discharge port is located closer to the center side than the end portion in the longitudinal direction of the manifold, and the upper wall surface forming the manifold has a downward gradient from the air discharge port toward the end portion,
The slope of the upper wall surface forming the manifold between the air outlet and the end is greater than the slope of the upper wall surface forming the manifold between the inlet and the air outlet,
The die head according to claim 1 , wherein a cross-sectional area of the manifold when cut perpendicularly to the longitudinal direction is the same over the longitudinal direction . A die coater comprising the die head according to claim 1 .

Images