JP6793236B2 - Coating device for film-forming substrate - Google Patents

Description

The present invention relates to a coating device for a film-forming substrate.

Conventionally, in a liquid crystal display device, a liquid (here, an alignment film material liquid) as a film forming material is applied by an inkjet method to a film forming region consisting of a display region of a substrate and a region around the substrate. Then, the sealant is cyclically applied by the dispensing method at positions at regular intervals around the film-forming region of the substrate, and the liquid crystal material is dropped and applied to the region surrounded by the sealing agent on the substrate by the dispensing method. ..

By the way, when the liquid which is the film-forming material described above is applied to the film-forming region of the substrate by the inkjet method, the liquid may wet and spread on the substrate and reach the region where the sealant is formed. When the liquid spreads to the area where the sealant is formed and an alignment film is formed in the area where the sealant is formed, the adhesion of the sealant to the substrate is deteriorated at the part of the alignment film.

Therefore, in order to suppress the wetting and spreading of the liquid of the film-forming material applied to the substrate to the outside of the film-forming region, as described in Patent Document 1, the film-forming region on the substrate and the sealing agent outside the film-forming region. In some cases, a concave groove surrounding the film-forming region is formed between the coating region and the coating region. In the process in which the liquid applied to the inside of the concave groove on the substrate is wetted and spread toward the periphery, the wet spread of the liquid is stopped by the concave groove so as not to spread to the sealant application area.

JP-A-2007-322627

As a recent trend, in liquid crystal display devices such as mobile terminals represented by mobile phones, it is required to make the size of the display area as large as possible with respect to the size of the product body. As a result, the outer region of the display region tends to be narrowed within a certain external dimension of the substrate.

Therefore, the distance between the concave groove formed in the region surrounding the film forming region on the substrate and the display region becomes short. For this reason, the liquid of the film-forming material that is dropped on the substrate inside the concave groove and spreads wet toward the outer periphery does not reduce the amount of the liquid in the process of reaching the concave groove, and the surface generated at the edge of the concave groove. Due to the tension, a liquid pool that rises like a bank is temporarily formed near the groove. When this liquid pool is formed, a part of the liquid that has been wet and spread from the inside to the outer peripheral edge on the substrate is repelled by the liquid pool and flows back toward the inside of the film forming region. As a result, the film thickness of the film-forming material becomes uneven even inside the display area.

An object of the present invention is to suppress the unevenness of the film thickness that occurs in the film forming region.

The present invention is a coating device that applies a film to a film-forming region of a substrate, and controls a coating head that drops a liquid droplet of a film-forming material onto the film-forming region of the substrate and the coating head. The substrate is a substrate on which a concave groove is formed along the outer periphery of the film-forming region, and a plurality of recesses are juxtaposed between the concave groove and the film-forming region. The shape of each recess in the recess group is such that the liquid applied on the substrate is from the concave groove to the film forming region as compared with the direction from the film forming region to the concave groove. The control device has a shape that makes it difficult to flow in the direction toward the direction of the coating head, so that the coating head drops the droplets on the concave groove or the concave portion of the substrate and then drops on the film-forming region. It is characterized by controlling.

According to the present invention, it is possible to suppress the unevenness of the film thickness that occurs in the film forming region.

FIG. 1 is a schematic plan view showing an example of a liquid crystal display panel to which the present invention is applied. FIG. 2 is a schematic perspective view showing an example of a coating device. FIG. 3 is a schematic cross-sectional view showing the substrate of the first embodiment. FIG. 4 is a schematic plan view showing a main part of the substrate of the first embodiment. FIG. 5 is a schematic plan view showing a main part of the substrate of the second embodiment. FIG. 6 is a schematic plan view showing a main part of the substrate of the third embodiment. FIG. 7 is a schematic plan view showing a main part of the substrate of the fourth embodiment. FIG. 8 is a schematic plan view showing a main part of the substrate of the fifth embodiment. FIG. 9 is a schematic plan view showing a main part of the substrate of the sixth embodiment. FIG. 10 is a schematic view showing a state in which the droplet is dropped into the concave groove. FIG. 11 is a cross-sectional view of the concave groove and the concave portion.

(Example 1) (FIGS. 1 to 4)
In the liquid crystal display panel to which the present invention is applied, as shown in FIG. 1, the film forming region 2 indicated by the alternate long and short dash line is composed of the display region DA of the rectangular substrate 1 and a small region around it, and this film. A liquid crystal forming material (here, an alignment film material liquid) is applied to the formation region 2 by the inkjet coating apparatus 100 shown in FIG. Then, around the film-forming region 2 of the substrate 1, the sealant 3 is cyclically applied at positions at regular intervals by the dispensing method, and the liquid crystal material (liquid crystal material) is applied to the region surrounded by the sealant 3 on the substrate 1. (Not shown) is dropped and applied by the dispense method. After that, the facing substrate (not shown) is bonded to each other via the sealant 3, the liquid crystal material is sealed, and the liquid crystal display panel is formed. The "film forming region 2" is not a region where the film is formed by the applied liquid, but a design region set as a region where the film is formed.

As shown in FIG. 2, the coating device 100 includes a Y-axis direction moving stage 102 on the gantry 101, and supports the substrate 1 on a substrate holding member 103 provided on the upper surface of the Y-axis direction moving stage 102. A gate-shaped frame 104 straddling the Y-axis direction moving stage 102 is provided on the gantry 101, and the gate-shaped frame 104 includes a plurality of coating heads 105 juxtaposed in the X-axis direction. The coating device 100 moves the substrate 1 in the Y-axis direction by the Y-axis direction moving stage 102, and is a film-forming material dropped from a large number of nozzles provided at regular intervals in the X-axis direction of the coating head 105. The liquid is dropped and applied to each position of the substrate 1 along the Y-axis direction. The coating device 100 controls the movement of the Y-axis direction moving stage 102 and the dropping of droplets (the amount of droplets dropped from the nozzles, the dropping interval (frequency), etc.) of the droplets from each nozzle of the coating head 105. It includes a control device 106.

FIG. 3 shows an AA cross section of the substrate 1 shown in FIG. 1, and FIG. 4 shows an AR region of the substrate 1 shown in FIG. That is, in the substrate 1, a long recessed groove 10 having a predetermined depth is formed along the outer peripheral side of the film forming region 2, and in this embodiment, a plurality of recessed grooves 10 are juxtaposed. The concave groove group 10N is formed. The concave groove group 10N is composed of a plurality of concave grooves 10 (first to nth concave grooves 11, 12, 13 ... 1n (not shown)) separated from each other along the outer periphery of the film forming region 2. The concave grooves 11, 12, 13 ... Are formed parallel to each side of the outer periphery of the film forming region 2 and form a plurality of layers with each other. The coating device 100 drops and coats a liquid, which is a film-forming material, on the substrate 1 on which the concave grooves 11, 12, 13 ... Of the concave groove group 10N are formed.

Hereinafter, this embodiment will be described in more detail.
(A) The concave groove 10 (a) formed on the outer periphery of the film forming region 2 prior to being applied to the film forming region 2 of the substrate 1 by the liquid of the film forming material dropped from the coating head 105 of the coating apparatus 100. It is also applied to the first to nth concave grooves 11, 12, 13 ... 1n). Therefore, the liquid that has been applied to the film forming region 2 and spreads wet toward the outer periphery and reaches the edge of the concave groove 10 is wet with the liquid that has already been applied to the edge of the concave groove 10. Therefore, it comes into contact with the liquid at the edge of the concave groove 10 and integrates with the liquid to penetrate into the concave groove 10 without forming a liquid pool.

Specifically, the substrate 1 is first supplied to the coating device 100 of FIG. At this time, the substrate 1 is supplied onto the substrate holding member 103 so that the long side direction is parallel to the Y direction. The substrate holding member 103 is positioned on the front side in the Y-axis direction of FIG. 2, which is the carry-in / carry-out position of the board 1. When the supply of the substrate 1 is completed, the control device 106 controls the Y-axis direction moving stage 102 to start the substrate holding member 103 toward the back side in the Y-axis direction in FIG. During this movement, droplets are ejected from each nozzle of the coating head 105 to the side of the concave groove group 10N on the substrate 1 closest to the display area DA, that is, the innermost concave groove 11. Will be done.

The concave groove 11 has a concave groove along the X direction and a concave groove along the Y direction, but with respect to the concave groove along the X direction, the concave groove along the X direction located on the front side of the substrate 1 and the rear portion. For each of the concave grooves located on the side, droplets are ejected from each nozzle located corresponding to the concave groove along the X direction at the timing when the concave groove passes under each nozzle of the coating head 105. Further, with respect to the concave groove along the Y direction, during the period from when the front end of the concave groove reaches under the coating head 105 to when the rear end passes under the coating head 105. Droplets are ejected from the nozzles located opposite the concave groove at preset arrangement intervals in the Y direction. The dropping of the droplet is controlled by the control device 106. That is, the control device 106 controls the coating head 105 so that the liquid droplets are dropped into the concave groove 10 before being dropped into the film forming region 2.

When the substrate holding member 103 reaches the end on the back side in the Y-axis direction of FIG. 2 or the position where the substrate 1 has passed through the coating head 105, this time, the substrate holding member 103 moves toward the side with the carry-in / carry-out position. It is moved, and during this movement, a liquid is dropped and applied to the inside of the film forming region 2. This liquid is dropped and applied from each nozzle in the coating head 105 located opposite to the film forming region 2 at the timing when the film forming region 2 of the substrate 1 passes under the coating head 105. The droplets are ejected so that the droplets are dropped at a preset arrangement interval. That is, the control device 106 controls the coating head 105 so that the liquid droplets are dropped into the concave groove 10 and then into the film forming region 2.

When the substrate 1 has passed under the coating head 105, the liquid drop application to the substrate 1 is completed, and the substrate holding member 103 reaches the carry-in / carry-out position, the liquid-coated substrate 1 is carried out. If there is a substrate 1 to be subsequently processed, the next substrate 1 is supplied to the substrate holding member 103 instead, and the above operation is repeated until there is no substrate 1 to be subsequently processed.

Further, the amount of the droplets dropped on the concave groove 10 described above shall be such that the dropped droplets are in contact with the edge portion located inside (the side closer to the display area DA) in the concave groove 10. The amount (size) can be determined experimentally, and the greater the depth of the groove, the greater the amount of droplets required. The amount of droplets dropped on the concave groove 10 described above is the amount of droplets dropped on the same position of the concave groove 10, and even if one drop is dropped or the same position is dropped multiple times. Good.

At this time, the droplet may spread over the entire groove width of the concave groove 10 as shown in (A) or (B) of FIG. 10, or may be concave as shown in (C) or (D) of FIG. It is not necessary to cover the entire groove width of the groove 10. The droplets may be dropped so as to be in contact with at least the inner edge (the side closer to the display area DA) of the concave groove 10. Further, the droplets may be continuously dropped on the concave groove 10 or may be dropped at intervals. Even if the liquid is dropped at intervals, the liquid that is wet and spreads from the film forming region 2 is dropped into the recessed groove 10 and enters the recessed groove 10 without forming a liquid pool from the wet portion. In any case, if a space for accommodating the liquid wet and spread from the film forming region 2 can be secured in the concave groove 10, the spread of the liquid wet and spread from the inside of the film forming region 2 can be suppressed. Therefore, in consideration of this point, the amount of droplets dropped into the concave groove 10 and the dropping interval of the droplets are determined. The amount and interval of the droplets can also be determined experimentally. Further, the dropping amount may be changed depending on the location in the concave groove 10.

Further, FIG. 10 shows an example in which a droplet is dropped only on the innermost concave groove 11 of the concave groove 10, but the present invention is not limited to this, and the liquid is also dropped on the outer concave grooves 12, 13 ... 1n. You may. By doing so, even if the liquid gets wet and spreads over the innermost concave groove 11, the wet spread can be stopped at any of the outer concave grooves 12, 13 ... 1n. Of course, it is the same whether the droplets are dropped on all the concave grooves 10 or only on the arbitrary concave grooves 10. It may be appropriately determined depending on the wet and spread state of the liquid in the film forming region 2. However, in order to effectively suppress the film thickness unevenness of the film-forming material caused by the liquid pool generated at the edge of the concave groove 11 causing a part of the liquid that has been wet and spread to bounce off and reach the display area DA. It is effective to drop the droplet into the concave groove 11 on the innermost side.

Further, although the example in which the liquid is dropped into the concave groove 10 and the liquid is dropped into the film forming region 2 separately has been described, they may be dropped together. That is, when the substrate 1 passes directly under the coating head 105, the droplets are dropped into the concave groove 10, and the liquid is also dropped into the film forming region 2 of the substrate 1. As a result, the coating is completed by moving the substrate holding member 103 once, and efficient coating can be performed. Further, by setting both ends of the movement of the Y-axis direction movement stage 102 as the carry-in / carry-out positions of the substrate 1, the coating can be repeatedly applied to the substrate 1 more efficiently.

The liquid of (a) described above is applied to the film forming region 2 by the coating device 100 after being applied to the concave groove 10 (droplets are dropped). That is, when the liquid applied to the film forming region 2 wets and spreads to the outer periphery and reaches the edge of the concave groove 10, the liquid already applied to the concave groove 10 in advance surely wets the edge of the concave groove 10. ing. Therefore, the formation of a liquid pool due to the liquid reaching the edge of the concave groove 10 is unlikely to occur, the rebound of the liquid due to the liquid pool is reliably suppressed, and the occurrence of film thickness unevenness can be reliably suppressed.

Further, in the concave groove 10, the amount of the liquid that wets and spreads from the inside of the film forming region 2 beyond the display area DA penetrates into the groove, and the amount of the liquid that wets and spreads to the outer periphery is reduced, and the sealant is applied. It also has a great effect of suppressing the spread of wetness to the area.

(B) The concave groove 10 of the above-mentioned (a) formed on the substrate 1 forms a concave groove group 10N provided on the outer periphery of the film forming region 2 so as to form a plurality of layers so as to be separated from each other, and further. It is assumed that the groove width Li (i = 1, 2, 3 ...) Is smaller as the outer concave groove 10 is separated from the outer circumference of the film forming region 2. That is, among the plurality of first concave grooves 11 to nth concave grooves 1n forming the concave groove group 10N, the groove width L1 of the first concave groove 11 closest to the outer periphery of the film forming region 2 is set to be the largest. A large amount of liquid that becomes wet and spreads is received by the wide first concave groove 11 to suppress rebound and wet spread, and then a smaller amount of liquid passes through each of the concave grooves 11, 12, 13 ... It is sequentially received in the concave grooves 12, 13 ... Of the narrower widths L2, L3 ... To suppress rebound and wet spread (L1> L2> L3 ...).

That is, the liquid is reliably received in the recessed grooves 11, 12, 13 ..., the coating liquid is wetted and spread to the sealing material coating region, and the liquid bounces in the above-mentioned (a) by the recessed grooves 11, 12, 13 ... All the concave grooves 10 have a wide width W formed by the concave groove group 10N along the direction orthogonal to the outer periphery of the film forming region 2 while suppressing the occurrence of film thickness unevenness in the film forming region 2. The size can be reduced as compared with the case where the size is reduced, the space occupied by the concave groove group 10N in the product body can be reduced, and a larger display area DA can be secured for the product body.

(C) The distance Si (i = 1, 2, ...) Formed on the substrate 1 between the adjacent concave grooves 10 and the concave grooves 10 of the above-mentioned (b) is smaller than the groove width Li of the concave grooves 10. As a result, in the concave groove group 10N of the above-mentioned (b), the total value of each groove width Li is compared with the case where the distance Si between the concave groove 10 and the concave groove 10 is equal to or larger than the groove width Li of the concave groove 10. The overall width W of the concave groove group 10N to which the total value of the intervals Si of the adjacent concave grooves 10 is added can be further reduced in size. Therefore, the space occupied by the concave groove group 10N in the product body can be further reduced, and a larger display area DA can be secured with respect to the product body.

In the concave groove group 10N of this embodiment, the groove widths L1 to L3 of the first concave groove 11 to the third concave groove 13 are L1 = 0.18 mm, L2 = 0.09 mm, and L3 = 0.06 mm. Further, the distance S1 between the first concave groove 11 and the second concave groove 12 and the distance S2 between the second concave groove 12 and the third concave groove 13 are set to S1 = S2 = 0.01 mm. When the above coating was applied to the substrate 1 on which the concave groove 10 having such a size was formed, unevenness of the alignment film formed in the display region DA could be suppressed.

(Example 2) (Fig. 5)
The substrate 1 of the second embodiment will be described.
(D) A recess group 20N in which a plurality of recesses 20 having a predetermined depth are juxtaposed is arranged between the concave groove 10 formed on the substrate 1 and the display area DA, and the shape of each recess 20 is a film forming region. The shape is such that the liquid applied to No. 2 is less likely to flow in the direction from the concave groove 10 to the film forming region 2 in the opposite direction than in the direction from the film forming region 2 to the concave groove 10. In this embodiment, the recesses 20 are arranged at predetermined pitch intervals along the outer peripheral edge of the film forming region 2.

The recess group 20N makes it difficult for the backflow in the opposite direction to flow as compared with the flow of the liquid from the inside to the outside of the film forming region 2. Specifically, the space between the recesses 20 formed by the recesses 20 of the recess group 20N is the main route when the liquid applied to the film forming region 2 gets wet and spreads. The inside of the film forming region 2 (the side closer to the display region DA) is wide and narrows toward the outside between the recesses 20. Further, the side facing the display area DA is configured so that the surface forming the recess 20 is not parallel to the display area DA. That is, since the space between the recesses 20 is narrowed from the concave groove 10 side toward the display region DA side, it is difficult for the liquid to flow, and the groove of the concave groove 10 spreads wet from the inside of the film forming region 2. At that time, a liquid pool is formed, and even if the liquid flow rebounds due to the liquid pool, the inward flow (backflow) caused by the rebound is suppressed (attenuated).

Compared with the case where the recess group 20N is not provided, the recess group 20N becomes resistant to the flow of wetting and spreading toward the outside (the direction from the film forming region 2 toward the recess groove 10). The speed of the flow at the time of reaching can be reduced as compared with the case where the recess group 20N is not provided. The slower the speed at which the liquid hits the liquid pool, the smaller the rebound of the liquid flow. As a result, the recess group 20N contributes to the suppression of the rebound. Further, since the liquid that spreads wet flows into each recess 20 when passing through the recesses 20N, this reduces the amount of liquid flowing toward the recesses 10N, and as a result, the edge of the recesses 10. The rebound of the liquid in the film can be suppressed, and the unevenness of the film thickness generated in the film forming region 2 can be suppressed.

Further, it has been experimentally found that even when the liquid flows into the recess 20 and the liquid is accumulated in the recess 20, the effect of suppressing the flow from the concave groove 10 side toward the film forming region 2 can be obtained. It has been confirmed. When the liquid film covering the surface of the substrate 1 and the recess 20 was observed, a bank-like swelling was observed on the liquid film along the contour of the recess 20, and the swelling of the liquid film formed along the contour of the recess 20 was observed. It is presumed that the portion acts as a resistance to the flow in the direction from the concave groove 10 side toward the film forming region 2, and this flow is suppressed.

Whether or not the liquid has entered the recess 20, the liquid rises at the contour of the recess 20, but the lines forming the contour are not parallel to the display area DA and are at an angle. Therefore, the rebound caused by the swelling of the liquid at the contour portion of the recess 20 does not directly face the display area DA side, and the bounce from the contour of each recess 20 juxtaposed interferes with each other to weaken the film formation. It is possible to suppress the unevenness of the film thickness that occurs in the region 2.

(E) Each of the recesses 20 forming the above-mentioned recess group 20N formed on the substrate 1 is a recess 21 composed of an isosceles triangle having an acute angle, and the base is parallel to the extending direction of the recess groove 10. By arranging the liquid so as to be located on the concave groove 10 side, the above-mentioned liquid flow (d) can be reliably formed.

In the outer peripheral edge of the film forming region 2, a recess 22 made of an isosceles triangle is arranged at a position directly facing the corners of two sides (vertical side and horizontal side) orthogonal to each other. The recess 22 has an isosceles triangle having the same shape as the recess 21, the base is located on the concave groove 10 side, and the central axis orthogonal to the bottom is 45 degrees with respect to the vertical and horizontal sides of the outer periphery of the film forming region 2. It is arranged diagonally so as to form a.

Further, on the outer circumference of the film forming region 2, recesses 21 and 22 are formed on both sides of the recess 22 formed of the above-mentioned isosceles triangle at a position directly facing the corners of the two sides (vertical side and horizontal side) that are orthogonal to each other. For example, a recess 23 made of a small isosceles triangle whose side length is halved is arranged. The recess 23 is arranged so that the bottom surface is parallel to the extending direction of the concave groove 10 and is located on the concave groove 10 side. The bottom of each recess 23 is arranged on the same straight line as the bottom of each recess 21.

In the recess group 20N of this embodiment, the length a and the height b of the bottoms of the recesses 21 and 22 are set to a = 0.06 mm and b = 0.10 mm, and the length c and the height d of the recess 23 are set to. It is set that c = 0.03 mm and d = 0.05 mm. Further, the pitch spacing p1 of the adjacent recesses 21 is set to p1 = 0.1 mm, and the arrangement spacing pc of the adjacent recesses 21 and the recesses 23 is set to pc = 0.085 mm. By forming the recess group 20N having such dimensions, the unevenness of the alignment film formed in the display region DA was further suppressed.

In the recess group 20N, for example, the pitch interval p1 of the recesses 21 composed of adjacent isosceles triangles can be set to p1 = 0.08 mm, and the density of the recesses 21 can be increased.

(Example 3) (Fig. 6)
The difference between the third embodiment and the first embodiment is the configuration of the recess group 20N formed on the substrate 1. The recess group 20N of the third embodiment has a small shape having the same shape as the recesses 23 arranged on both sides of the recesses 22 between the adjacent recesses 21 and the recesses 21 and between the adjacent recesses 21 and the recesses 22. The recess 24 made of an isosceles triangle is arranged. The vertices of each recess 24 are arranged on the same straight line as the vertices of the recesses 21 and 22, and are arranged in the center between the adjacent recesses 21 and 22 and in the center between the adjacent recesses 21 and 22. To. The pitch interval p2 of the adjacent recesses 24 is set to p2 = 0.1 mm. By arranging the recess 24 with such dimensions, the unevenness of the alignment film formed in the display region DA was suppressed.

(Example 4) (Fig. 7)
The difference between the fourth embodiment and the third embodiment is the configuration of the recess group 20N formed on the substrate 1. In the recess group 20N of the fourth embodiment, the vertices of the recesses 24 arranged between the adjacent recesses 21 and the recesses 21 and between the adjacent recesses 21 and the recesses 22 are set to the vertices of the recesses 21 and 22. It is retracted to the side of the concave groove 10 from the straight line to be connected by a distance e = 0.025 mm. By arranging the recesses 24 with such dimensions, unevenness of the alignment film formed in the display region DA was suppressed as in Example 3.

(Example 5) (Fig. 8)
The difference between the fifth embodiment and the first embodiment is the configuration of the recess group 20N formed on the substrate 1. In the recess group 20N of the fifth embodiment, the recess 25 having a rhombus shape is arranged between the adjacent recesses 21 and 21 and between the adjacent recesses 21 and 22. The length f of the shorter diagonal line of the recess 25 and the length g of the longer diagonal line are set to f = 0.03 mm and g = 0.10 mm. Each of the two vertices on the longer diagonal of each recess 25 is located on the same straight line as each of the vertices and bottoms of each recess 21, 22 and at the center between the adjacent recesses 21 and 21. It is arranged in the center between the recesses 21 and the recesses 22 adjacent to each other. Even when the recess 25 was arranged with such a shape and size, the unevenness of the alignment film formed in the display region DA was suppressed.

(Example 6) (Fig. 9)
The difference between the sixth embodiment and the fourth embodiment is the configuration of the recess group 20N formed on the substrate 1. In the recess group 20N of Example 6, each recess 21 in the recess group 20N of Example 4 is replaced with a recess 26 having a diamond shape having the same shape as the recess 25 used in Example 5. Even when the recess 26 was arranged with such a shape and size, unevenness of the alignment film formed in the display region DA was suppressed as in Example 3.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like within a range not deviating from the gist of the present invention. Included in the present invention. For example, the substrate 1 of the present invention is not limited to the one in which the concave groove group 10N composed of the plurality of concave grooves 10 is arranged, and may be the one in which a single concave groove 10 is arranged.

Further, in Examples 2 to 6 described above, a recess made of an isosceles triangle is located at a position directly facing the corners of the two sides (vertical side and horizontal side) orthogonal to each other along the outer peripheral edge of the film forming region 2. 22 are arranged. However, the recess 22 may not be arranged. Further, in Examples 2 to 6 described above, small isosceles triangular recesses 23 are arranged between the recesses 21 and the recesses 22 adjacent to each other on both sides of the recesses 22. Further, in Examples 3 and 4, a recess 24 having the same shape as the recess 23 is arranged between the adjacent recesses 21 and 21 and between the adjacent recesses 21 and 22. These recesses 23 and 24 do not necessarily have to be arranged. Further, the triangular recess 22, the recess 23, the recess 24, the diamond-shaped recess 25 or the recess 26 may be appropriately replaced and arranged at the corner portion in the above-described embodiment, or these may be appropriately combined and arranged. good.

Further, in the second embodiment, it is not always necessary to drop the droplet into the concave groove 10 prior to the application of the liquid to the film forming region 2. However, as in Example 1, droplets of the liquid to be applied to the recess 20 may be dropped into the recess 20 prior to application to the film forming region 2. In this way, it is possible to promote the liquid that spreads by dropping the liquid into the film forming region 2 to flow into each of the recesses 20 when passing through the recesses 20N. Of course, the droplet may be dropped into the concave groove 10 in the same manner as in Example 1 before dropping into the film forming region 2. As a result, the rebound of the liquid at the edge of the concave groove 10 is further suppressed, and the unevenness of the film thickness generated in the film forming region 2 can be suppressed.

Further, similarly to the first embodiment, the width of the concave groove 10 of the substrate having the concave portion 20 may be narrowed as the distance from the film forming region 2 increases, or between the concave groove 10 and the concave groove 10 adjacent to each other. The interval Si may be smaller than the groove width Li of the concave groove 10. As a result, as in the first embodiment, the space occupied by the concave groove group 10N in the product body is reduced while suppressing the unevenness of the alignment film formed in the display area DA, and the display area larger than the product body. DA can be secured.

The concave groove may be an annular shape surrounding the outer periphery of the film forming region 2, or may be an array of a plurality of long concave grooves. Further, the concave groove 10 is not limited to an annular shape closed at the outer periphery of the film forming region 2, and may have a shape having a gap in a part thereof.

Further, in the above-described embodiment, the recess group is composed of an isosceles triangle and a rhombus recess, but other shapes such as a circle, an ellipse, a polygon other than a triangle or a rhombus, and a star shape may be used. As for the shape of each recess 20, the liquid applied to the film forming region 2 is less likely to flow in the direction from the concave groove 10 to the film forming region 2 than in the direction from the film forming region 2 to the concave groove 10. The shape and arrangement may be used, and different shapes and arrangements may be combined.

Further, the concave groove and the edge of the concave portion may have a curved surface or a slope. For example, it is a substrate 1 in which a concave groove 10 is formed along the outer periphery of the film forming region 2, and is provided with a recess group 20N in which a plurality of concave grooves 20 are juxtaposed between the concave groove 10 and the film forming region 2. The shape of each recess 20 of the recess group 20N is such that the liquid applied on the substrate 1 is directed from the concave groove 10 to the film forming region 2 as compared with the direction from the film forming region 2 to the concave groove 10. The substrate 1 may be a substrate 1 having a shape that is difficult to flow and having a curved surface or a slope on one or both edges of the concave groove 10 and the concave portion 20. FIG. 11 shows an example (A) having a vertical surface at the edge of the concave groove 10 and the concave portion 20 of the substrate 1, an example having a slope (B), and an example having a curved surface (C).

By forming the curved surface or the slope in this way, the surface tension generated at the edge is weakened, the swelling of the liquid at the contour portion of the concave groove 10 and the concave portion 20 is suppressed, and the rebound of the liquid caused by the swelling is also suppressed. In addition, the liquid can easily enter the concave groove 10 and the concave portion 20, and the wet spreading of the liquid can be received and the wet spreading can be suppressed more reliably. Such a curved surface or a slope may be provided on the entire circumference or all edges of the concave groove 10 or the concave portion 20, or may be provided only on a part of the edge, for example, the edge on the display area DA side. When provided on the edge of the display area DA side, the effect of suppressing the rebound of the liquid to the display area DA side, reducing the amount of liquid that wets and spreads to the outer periphery, and suppressing the wet spread to the sealant application area is also obtained. large. Of course, the edges of the concave groove 10 and the concave portion 20 may be curved or sloped, and then droplets may be dropped as in the first embodiment. Thereby, the above-mentioned effect can be further enhanced.

Further, in the substrate 1 in which the first flow adjusting portion is formed along the outer periphery of the film forming region, a plurality of second flow adjusting portions are formed between the first flow adjusting portion and the film forming region 2. A group of second flow adjusting portions arranged side by side is provided, and the shape of each second flow adjusting portion is such that the liquid applied on the substrate 1 is directed from the film forming region 2 toward the first flow adjusting portion. In comparison, the substrate 1 may have a shape that makes it difficult to flow in the direction from the first flow adjusting portion toward the film forming region 2.

"Flow adjustment" in the first flow adjustment unit and the second flow adjustment unit means suppressing or promoting the flow of the liquid. Here, the first flow adjusting unit and the second flow adjusting unit may be a concave portion 20 or a convex portion. That is, it does not matter whether the substrate 1 is recessed or protrudes from a flat surface having the same height as the display area DA. Both the first flow adjusting portion and the second flow adjusting portion may be concave portions 20, or both may be convex portions. Either one of the first flow adjusting portion and the second flow adjusting portion may be a concave portion 20 and the other may be a convex portion.

The second flow adjustment unit is an isosceles triangle with an acute angle, and the base of the isosceles triangle is parallel to the extending direction of the first flow adjustment unit and is on the side of the first flow adjustment unit. It may be arranged so as to be located at.

The first flow adjusting part forms a group of first flow adjusting parts provided so as to form a plurality of layers that are separated from each other on the outer periphery of the film forming region, and the first outer side that is separated from the outer periphery of the film forming region 2. The width may be smaller as the flow adjusting portion.

Further, the edges of the first flow adjusting section and the second flow adjusting section may have a curved surface or a slope. For example, when the first flow adjusting portion or the second flow adjusting portion is a convex portion, the side surface of the edge portion may have a curved surface or an inclined surface.

Further, in the above-described embodiment, the example in which the inkjet type coating head is used has been described, but it can be applied to the one using another type of coating head as long as the liquid is dropped in the form of droplets. ..

1 Substrate 2 Film forming region 10N Recessed groove group 10, 11, 12, 13 Recessed groove 20N Recessed groove group 20, 21, 22, 23, 24, 25, 26 Recessed 100 coating device

Claims (3)

A coating device that applies a film to the film-forming region of a substrate.
A coating head that drops a liquid droplet of a film-forming material onto the film-forming region of the substrate, and a coating head.
It has a control device for controlling the coating head, and has
The substrate is a substrate on which a concave groove is formed along the outer periphery of the film-forming region, and includes a group of recesses in which a plurality of recesses are juxtaposed between the concave groove and the film-forming region. The shape of each recess in the recess group is such that the liquid applied on the substrate is less likely to flow in the direction from the recess to the film-forming region than in the direction from the film-forming region to the recess. None,
The control device is characterized in that the coating head controls the coating head so that the droplet is dropped into the recessed groove or the recess of the substrate and then dropped onto the film forming region. Coating device. The recess group of the substrate is an isosceles triangular recess arranged so that the apex angle is an acute angle, the base is parallel to the extending direction of the recess, and the recess is located on the recess side. The coating apparatus for a film-forming substrate according to claim 1. The recessed grooves of the substrate form a group of recessed grooves provided on the outer periphery of the film forming region so as to form a plurality of layers that are separated from each other.
The coating device for a film-forming substrate according to claim 1 or 2, wherein the control device controls the coating head so that the droplets are dropped only into the innermost concave groove.

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