JP2012196658A - Coating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating apparatus including a first slit segment and a second slit segment.SOLUTION: The first slit segment has a first wall and a second wall and the first slit is formed between the first wall and the second wall. A second slit segment has a first coating lip and a second coating lip, the first coating lip is connected with the first wall, the second coating lip is connected with the second wall and a second slit is provided between the first coating lip and the second coating lip. The width of the second slit is wider than that of the first slit. The ratio of the width of the second slit to the width of the first slit lies within a range of 1.2 to 3.8. The ratio of the distance from the first coating lip to the center line of the first slit to the distance from the second coating lip to the center line of the first lies within a range of 0.5 and 1.5. Consequently, stable bidirectional ultrathin coating is carried out by the coating apparatus.

Description

  The present invention relates to a coating apparatus, and more particularly to a coating head for a film coating machine.

  As the luminous efficiency, lifetime, and reliability of organic light emitting diodes (OLEDs) continue to improve and the price of OLEDs clearly decreases, the proportion of OLED luminaires in the market is gradually increasing.

  In the manufacture of OLED panels, the ultra-thin film coating technology greatly affects the manufacturing cost of products. Therefore, it is an important issue for the designer to uniformly apply the photoresist liquid to the nanometer-scale thickness on the substrate using the coating head of the coating machine.

  In general, the coating head has a liquid outlet and a slit connected to the liquid outlet, and the photoresist liquid flows out from the liquid outlet through the slit. The coating head is divided into an upper coating lip and a lower coating lip by a slit, and the substrate moves in the direction from the upper coating lip to the lower coating lip with respect to the coating head. While the photoresist solution flows out through the liquid outlet and is applied onto the substrate, the substrate moves continuously relative to the application head. As the substrate moves, the photoresist liquid forms a circulation region at the liquid outlet and then becomes photoresist droplets due to the effect of the movement of the substrate and the effect of the interfacial energy of the material. If a large amount of photoresist droplets fall from the liquid outlet toward the lower coating lip (downstream end) during coating on the substrate, the coating effect is reduced, for example, the film thickness becomes uneven or thick. . Therefore, stably holding the photoresist droplets at the liquid outlet to ensure the quality of the coating process is an important factor to consider in the coating head design.

  In prior art coating head designs, the lower coating lip protrudes beyond the upper coating lip to avoid photoresist droplets flowing toward the lower coating lip. In this way, good quality of application is ensured and it is prevented that photoresist droplets flow toward the lower application lip and become insufficiently applied. However, the coating head design in the prior art cannot prevent the photoresist droplet from flowing toward the upper coating lip and at the same time prevent the photoresist droplet from flowing toward the lower coating lip. It can only prevent the photoresist droplets from flowing towards the lower coating lip. Therefore, the design of the coating head in the prior art is only suitable for moving and processing the substrate in a single direction with respect to the coating head, and is therefore inconvenient in the coating process.

  Accordingly, the present invention provides a coating apparatus that solves the problems of the prior art, in which the coating head of the coating machine can maintain stability only by coating in a single direction, and causes inconvenience in the coating process. is there.

  The present invention provides a coating apparatus suitable for guiding a coating material on a surface of a substrate. The coating apparatus includes a first slit segment and a second slit segment. The first slit segment has a first wall and a second wall. A first slit is provided between the first wall and the second wall. The second slit segment has a first application lip, a second application lip, and an application material outlet. The first application lip is connected to the first wall, the second application lip is connected to the second wall, and a second slit is provided between the first application lip and the second application lip. The two ends of the second slit are connected to the application material outlet and the first slit, respectively. The width of the second slit is larger than the width of the first slit. The ratio of the width of the second slit to the width of the first slit is between 1.2 and 3.8. The ratio of the distance from the first coating lip to the first slit centerline to the distance from the second coating lip to the first slit centerline is between 0.5 and 1.5. .

  According to the coating apparatus of the present invention, the width of the second slit is larger than the width of the first slit, and the first slit to the first slit relative to the distance from the second slit to the center line of the first slit. The ratio of the distance to the centerline of one slit is between 0.5 and 1.5. Thus, the dimensions of the applicator device can improve the quality of the bi-directional ultra-thin film application for the applicator and make the application process more convenient.

  These and other aspects of the invention will be apparent from the following description of preferred embodiments in conjunction with the following drawings.

  The accompanying drawings illustrate one or more embodiments of the invention and, together with the written description, serve to explain the principles of the invention. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like elements of the embodiments.

1 is a structural diagram of a coating apparatus according to an embodiment of the present invention. It is structure sectional drawing of the coating device by embodiment which concerns on this invention. It is a partial structure sectional view of the coating device of Drawing 1B. It is the schematic of the coating material apply | coated on a board | substrate with the coating device by embodiment of this invention. It is another schematic diagram of the coating material apply | coated on a board | substrate with the coating device by embodiment of this invention. FIG. 3 is a flow field analysis diagram of a coating material during a coating process according to an embodiment of the present invention. It is a structure sectional view of the coating device by another embodiment of the present invention. It is structural sectional drawing of the coating device by another embodiment of this invention. It is structural sectional drawing of the coating device by another embodiment of this invention.

  Referring to FIGS. 1A to 1C together with FIG. 2A, FIG. 1A is a structural view of a coating apparatus according to an embodiment of the present invention, FIG. 1B is a structural sectional view of the coating apparatus, and FIG. 1C is a coating apparatus of FIG. FIG. 2A is a schematic view of a coating material applied on a substrate by a coating apparatus.

  The invention coating apparatus 10 according to this embodiment is a coating head of an ultrathin film coating machine. The coating apparatus 10 includes a coating material outlet 230 and a coating material inlet 240 on the opposite side of the coating material outlet 230. The coating apparatus 10 is used for guiding a coating material and coating it on the surface of the substrate 400 in the form of an ultrathin film. The coating apparatus 10 includes a first slit segment 100 and a second slit segment 200.

  The first slit segment 100 has a first wall 110 and a second wall 120 on the opposite side of the first wall 110. A first slit 101 is provided between the first wall 110 and the second wall 120. Furthermore, the first wall 110 has a first wall surface 111 and a first side wall surface 112 adjacent to the first wall surface 111, and the second wall 120 includes a second wall surface 121, And a second side wall surface 122 adjacent to the second wall surface 121. The first wall surface 111 of the first wall 110 faces the second wall surface 121 of the second wall 120, and therefore the first slit 101 is between the first wall surface 111 and the second wall surface 121. Formed. The first slit 101 has a width D1, and the width D1 is a distance between the first wall surface 111 and the second wall surface 121. The width D1 may be 100 μm.

  The second slit segment 200 has a first application lip 210, a second application lip 220, and an application material outlet 230. The first application lip 210 is connected to the side of the first wall 110 having the first side wall surface 112, and the second application lip 220 is connected to the second side wall surface 122 of the second wall 120. Lead to the side with. A second slit 201 is provided between the first application lip 210 and the second application lip 220. Two ends of the second slit 201 are connected to the coating material outlet 230 and the first slit 101, respectively. The second slit 201 has a width D2, and the width D2 of the second slit 201 is larger than the width D1 of the first slit 101. The ratio of the width D2 of the second slit 201 to the width D1 of the first slit 101 is between 1.2 and 3.8. Further, the first application lip 210 has a first lip surface 211 and a first surface 212 adjacent to the first lip surface 211, and the second application lip 220 is a second lip surface. 221 and a second surface 222 adjacent to the second lip surface 221. The first lip surface 211 of the first application lip 210 is opposed to the second lip surface 221 of the second application lip 220, and thus the second slit 201 is connected to the first lip surface 211 and the second lip surface 221. It is formed between the lip surface 221. The width D <b> 2 of the second slit 201 is a distance between the first lip surface 211 and the second lip surface 221.

  Furthermore, the first surface 212, the second surface 222, and the coating material outlet 230 face the same direction, and the first surface 212 and the second surface 222 are in the same plane. Furthermore, when the coating apparatus 10 is used for coating the substrate 400, the first surface 212, the second surface 222, and the coating material outlet 230 simultaneously face the substrate 400. The distance of the first coating lip 210 with respect to the substrate 400 is the same as the distance of the second coating lip 220 with respect to the substrate 400. Further, the distance from the first surface 212 and the second surface 222 to the substrate 400 is generally between 50 μm and 100 μm. The feature that the first surface 212 and the second surface 222 are in the same plane does not limit the present disclosure, and in another embodiment of the present disclosure, the first surface 212 and the second surface 222 are the same. Note that it does not have to be flat. Further, the distance from the first surface 212 to the substrate 400 may be longer or shorter than the distance from the second surface 222 to the substrate 400.

  The first slit 101 has a center line M. The first lip surface 211 is located at a first distance a from the center line M of the first slit 101, and the second lip surface 221 is located at a second distance b from the center line M of the first slit 101. In position. The ratio of the first distance a to the second distance b is between 0.5 and 1.5. Furthermore, in another embodiment, the ratio of the first distance a to the second distance b may be between 0.8 and 1.2.

  Further, the second slit 201 has a depth H 2, and the depth H 2 is a distance between the coating material outlet 230 and the first slit 101. The depth H2 may be in the range of 20 μm to 110 μm. In another preferred embodiment, the depth H2 may be in the range of 40 μm to 90 μm. Alternatively, in yet another more preferred embodiment, the depth H2 may be in the range of 60 μm to 70 μm.

  In this embodiment, the first lip surface 211 of the first application lip 210 is connected to the first side wall surface 112 of the first wall 110, and the first lip surface 211 and the first side wall surface 112. Effectively forms a right angle between them. The second lip surface 221 of the second application lip 220 is connected to the second side wall surface 122 of the second wall 120, and the second lip surface 221 and the second side wall surface 122 are substantially Form a right angle between them. The first lip surface 211 and the first side wall surface 112 effectively form a right angle therebetween, and the second lip surface 221 and the second side wall surface 122 are substantially between them. The feature of forming a right angle with respect to the present invention does not limit the present invention. For example, in another embodiment of the present disclosure, an obtuse angle θ1 may be formed between the first lip surface 211 and the first side wall surface 112 as shown in FIG. An obtuse angle θ2 may be formed between the first side wall surface 122 and the second side wall surface 122. The obtuse angle θ1 and the obtuse angle θ2 are between 90 ° and 150 °. Alternatively, in still another embodiment of the present invention, as shown in FIG. 5, the first lip surface 211 may be connected to the first side wall surface 112 by the first arc surface 113 and the second lip surface. 221 may be connected to the second side wall surface 122 by the second arcuate surface 123.

  Furthermore, in another embodiment, an acute angle θ3 may be formed between the first lip surface 211 and the first surface 212. An acute angle θ4 may be formed between the second lip surface 221 and the second surface 212. The acute angle θ3 and the acute angle θ4 are between 86 ° and 90 ° as shown in FIG.

  Referring to FIGS. 2A and 3, FIG. 3 is an analysis diagram of a flow field of a coating material during a coating process according to an embodiment of the present invention.

  The substrate 400 of FIG. 2A moves from the first coating lip 210 toward the second coating lip 220 with respect to the coating material outlet 230. At that time, the air-liquid branch surfaces 520 and 530 of the coating material 500 and the outside air between the coating material outlet 230 and the substrate 400 have arcuate surfaces that are recessed toward the coating material outlet 230. Such a phenomenon indicates that the coating material 500 is not accumulated at the coating material outlet 230, and therefore, when the coating material 500 is coated on the substrate 400 in the form of an ultrathin film using the coating device 10, the coating material 500 is not coated. The apparatus 10 has good and stable coating quality, and the problem that the film thickness is large or non-uniform due to the accumulation of coating material does not occur.

  Referring to FIG. 3, when the coating apparatus 10 applies the coating material 500 onto the substrate 400, the coating material 500 is affected by the movement of the substrate 400 and forms a clockwise circulation region 510 at the coating material outlet 230. Thus, droplets of the coating material are formed. With the structural design of the coating apparatus 10 of this embodiment, the droplets of the coating material formed by the coating material 500 can be kept between the first lip surface 211 and the second lip surface 221, thereby The stability of the coating process is guaranteed, the coating material 500 is prevented from forming a non-uniform film thickness on the substrate 400, and the film thickness is prevented from exceeding a preset film thickness range. .

  In the above embodiment, the substrate 400 moves from the first coating lip 210 toward the second coating lip 220 with respect to the coating material outlet 230. However, such features do not limit the present disclosure. Furthermore, the coating apparatus 10 according to the present disclosure enables stable bidirectional ultrathin film coating.

  Referring to FIG. 2B, in FIG. 2B, the substrate 400 moves from the second coating lip 220 toward the first coating lip 210 with respect to the coating material outlet 230. Here, the air-liquid branch surfaces 520 and 530 of the coating material 500 and the outside air between the coating material outlet 230 and the substrate 400 have arcuate surfaces that are recessed toward the coating material outlet 230. Such a phenomenon indicates that the coating material 500 is not accumulated on the first coating lip 210 or the second coating lip 220, and therefore, the coating material 500 is coated on the substrate 400 using the coating device 10. Sometimes, the applicator 10 reliably has good and stable processing quality. Therefore, the shape of the gas-liquid branch surfaces 520 and 530 between the coating material 500 and the outside air in FIGS. 2A and 2B enables the coating apparatus 10 of the present disclosure to perform stable bidirectional ultrathin film coating. Proven to do so. Compared with the coating head of the prior art coating machine that can maintain only the good quality of the unidirectional coating of the substrate 400, the coating apparatus 10 of this embodiment can achieve good processing. According to the structural design of the coating apparatus 10 of this embodiment, in the actual coating process, the substrate 400 moves from the second coating lip 220 toward the first coating lip 210 with reference to the coating material outlet 230. In addition, even when moving from the first coating lip 210 toward the second coating lip 220, the film thickness of the liquid of the coating material 500 coated on the substrate 400 is uniform and is less than 10 μm. After the liquid film on the substrate 400 is dried to be a solid film, the thickness of the solid film can be reduced to a nanometer-scale film thickness of less than 1 μm.

  According to the coating apparatus of the above-described embodiment, the width of the second slit is larger than the width of the first slit, and the first coating with respect to the distance from the second coating lip to the center line of the first slit. The ratio of the distance from the lip to the center line of the first slit is between 0.5 and 1.5. Therefore, the design of such a size of the coating device can effectively and stably keep the droplets of the coating material in the circulation region formed between the first coating lip and the second coating lip. . Thus, the coating apparatus of this embodiment can improve the quality of a good bi-directional ultra-thin film coating, thereby making the coating process convenient.

DESCRIPTION OF SYMBOLS 10 Application | coating apparatus 100 1st slit segment 101 1st slit 110 1st wall 120 2nd wall 200 2nd slit segment 201 2nd slit 210 1st coating lip 220 2nd coating lip 230 Application material outlet 400 Substrate 500 Application material a First distance b Second distance D1 Width of first slit 101 D2 Width of second slit 201 M Center line of first slit 101

Claims (11)

A coating apparatus suitable for guiding a coating material to be coated on the surface of a substrate,
A first slit segment having a first wall and a second wall provided with a first slit therebetween,
A first application lip connected to the first wall; a second application lip connected to the second wall; and an application material outlet; between the first application lip and the second application lip. And a second slit segment having a second slit having a width larger than that of the first slit and two ends connected to the application material outlet and the first slit, respectively.
The ratio of the width of the second slit to the width of the first slit is between 1.2 and 3.8, with respect to the distance from the second coating lip to the centerline of the first slit. The ratio of the distance from the first coating lip to the center line of the first slit is between 0.5 and 1.5.   The first application lip has a first surface, the second application lip has a second surface, and the first surface, the second surface, and the application material outlet are in the same direction. The coating apparatus according to claim 1, wherein the first surface and the second surface are in the same plane.   The coating apparatus according to claim 1, wherein the second slit has a second slit depth, and the second slit depth is in a range of 20 μm to 110 μm.   The coating apparatus according to claim 3, wherein the second slit depth is preferably in a range of 40 μm to 90 μm.   The coating apparatus according to claim 4, wherein the second slit depth is preferably in a range of 60 μm to 70 μm.   The ratio of the distance from the first coating lip to the center line of the first slit to the distance from the second coating lip to the center line of the first slit is preferably 0.8 and 1 2. The coating apparatus according to claim 1, wherein the coating apparatus is between.   The first wall has a first side wall surface, the first application lip is connected to the first side wall surface, and is between the first side wall surface and the first application lip. The coating apparatus according to claim 1, wherein an obtuse angle is formed on the surface, and the obtuse angle is between 90 ° and 150 °.   The second wall has a second side wall surface, the second application lip is connected to the second side wall surface, and is interposed between the second side wall surface and the second application lip. The coating apparatus according to claim 1, wherein an obtuse angle is formed on the surface, and the obtuse angle is between 90 ° and 150 °.   The first wall has a first side wall surface, the first application lip is connected to the first side wall surface, and the first side wall surface and the first application lip are arcs. The coating device according to claim 1, wherein the coating device is connected by a surface.   The second wall has a second side wall surface, the second application lip is connected to the second side wall surface, and the second side wall surface and the second application lip are circular arcs. The coating device according to claim 1, wherein the coating device is connected by a surface.   The first application lip has a first lip surface and a first surface connected to the first lip surface, and the second application lip has a second lip surface and the second lip surface. A second surface connected to the lip surface, wherein the first lip surface is opposed to the second lip surface, and between the first lip surface and the first surface, or the first surface. The coating apparatus according to claim 1, wherein an acute angle is formed between the second lip surface and the second surface, and the acute angle is between 86 ° and 90 °.

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