JP2014154482A - Organic el display device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL display device improved in picture quality, and a method for manufacturing the organic EL display device.SOLUTION: An organic EL display device according to an embodiment of the present invention includes: a first substrate including an organic EL light emitting layer; a second substrate disposed to face the first substrate; a dam material disposed between the first substrate and the second substrate and at the outside of a display region where the organic EL light emitting layer is disposed; and a filler filled in a space between the dam material and the first and second substrates. The dam material includes a portion tilted with respect to the faces of the first substrate and the second substrate.

Description

  The present invention relates to an organic EL display device including a sealing means for an organic EL (electro-luminescence) light emitting layer and a method for manufacturing the same.

  In recent years, organic EL display devices have been developed for the purpose of reducing the thickness, increasing the brightness, and increasing the speed of display panels. An organic EL display device is a display device having pixels composed of organic light-emitting diodes, and has a fast reaction speed because there is no mechanical operation, so that each pixel itself emits light. Since high-luminance display is possible and a backlight is not required, it is possible to reduce the thickness, which is expected as a next-generation display device.

  The organic EL light emitting layer is formed on a hard substrate such as glass. For example, in order from the substrate side, a TFT drive circuit layer, a reflective electrode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron The injection layer and the transparent electrode can be laminated.

  The organic EL light emitting layer rapidly deteriorates when exposed to moisture in the atmosphere, and thus needs to be sealed from the outside air. For this reason, the surface of the organic EL light emitting layer of the substrate is covered with a sealing substrate made of a hard transparent member such as glass. As the sealing substrate, for example, a color filter, a thin film device having a touch panel function, or the like may be formed on a hard transparent member such as glass.

  Conventional organic EL display devices are known in which the gap between the substrate on which the organic EL light emitting layer is formed and the sealing substrate is filled with a transparent resin such as an epoxy resin (such as an ultraviolet curable type or a thermosetting type). (For example, refer to Patent Document 1). The pixel substrate on which the organic EL light emitting layer is formed and the sealing substrate that protects the organic EL light emitting layer are bonded to each other through a transparent resin, thereby keeping the distance between them constant. And the surface of the sealing substrate are kept parallel, and reflection and refraction at the interface between the two are prevented.

JP 2010-225569 A

  However, in the conventional organic EL display device, when the substrate and the sealing substrate are bonded to each other through the resin, the unevenness formed on the surface of the substrate and the sealing substrate causes a problem between the substrate and the sealing substrate. A region that is not filled with resin occurs in the gap, and bubbles (vacuum accumulation) may be formed in the resin.

  The present invention is intended to solve the problem of such a conventional configuration, and can improve the image quality of the organic EL display device and improve the yield and reduce the manufacturing cost. An object of the present invention is to provide an organic EL display device and a manufacturing method thereof.

  An organic EL display device according to an embodiment of the present invention includes a first substrate including an organic EL light emitting layer, a second substrate disposed to face the first substrate, the first substrate, and the second substrate. And a dam material disposed outside the display region where the organic EL light emitting layer is disposed, and a filler filled in a space between the first substrate, the second substrate, and the dam material The dam material includes a portion inclined with respect to the surfaces of the first substrate and the second substrate.

  The dam material and the filler may each be a transparent resin, and the dam material may be a resin having a higher viscosity before curing than the filler.

  The first substrate may include a terminal region in a region separated from the display region by the dam material.

  In addition, in the method for manufacturing an organic EL display device according to an embodiment of the present invention, an organic EL light emitting layer constituting a display region for displaying an image is formed on a first substrate, and the organic EL light emitting layer is formed. Forming a sealing film on the first substrate, disposing a dam material surrounding the display region on the sealing film, disposing a filler inside the dam material, and forming the dam material and the filling After overlapping the first substrate and the second substrate with a material sandwiched between them, the first substrate or the second substrate is moved in the surface direction of the first substrate or the second substrate, and the dam material and The method includes curing the filler and bonding the first substrate and the second substrate.

  The first substrate includes a plurality of first alignment marks outside the display region, the second substrate includes a plurality of second alignment marks outside a region corresponding to the display region, and the plurality of first alignment marks. After aligning and overlaying the first substrate and the second substrate using a mark and the plurality of second alignment marks, the first substrate or the second substrate is moved to move the dam material and The filler may be cured.

  By moving the first substrate or the second substrate in the horizontal direction, the first substrate and the surface on which the dam material connects the portion in contact with the first substrate and the portion in contact with the second substrate You may form including the part inclined with respect to each opposing surface of a 2nd board | substrate.

  According to the organic EL display device and the manufacturing method thereof of the present invention configured as described above, an organic EL display device capable of improving the image quality and improving the yield and reducing the manufacturing cost, and A manufacturing method thereof can be provided.

It is sectional drawing which shows schematic structure of the laminated structure of the organic electroluminescence display which concerns on one Embodiment of this invention. It is a figure which shows schematic structure of the organic electroluminescence display which concerns on one Embodiment of this invention, (a) is a plane perspective view of an organic electroluminescence display, (b) is the organic electroluminescence display shown to (a). It is sectional drawing of an apparatus. It is a figure for demonstrating the manufacturing process of the organic electroluminescence display which concerns on one Embodiment of this invention. It is the enlarged view of the part X shown by the broken line in FIG.3 (e). It is a figure for demonstrating the manufacturing process of the organic electroluminescence display which concerns on one Embodiment of this invention. It is a figure for demonstrating the manufacturing process of the organic electroluminescence display which concerns on one Embodiment of this invention. It is a figure which shows schematic structure of the conventional organic electroluminescence display, (a) is a plane perspective view of an organic electroluminescence display, (b) is sectional drawing of the organic electroluminescence display shown to (a). . It is a figure which shows schematic structure of the conventional organic electroluminescence display, (a) is an enlarged view of the part Y shown with the broken line in Fig.7 (a), (b) is the structure shown to (a). It is sectional drawing. It is a figure for demonstrating the manufacturing process of the conventional organic electroluminescence display. It is a figure for demonstrating the manufacturing process of the conventional organic electroluminescence display.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, this invention is not limited to the following embodiment, In the range which does not deviate from the summary, it can implement in various aspects.

  Hereinafter, the configuration of an organic EL display device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing an example of a laminated structure of an organic EL display device 10 according to an embodiment of the present invention. As shown in FIG. 1, the organic EL light emitting layer 1 is formed on a substrate 2 such as glass. Although detailed illustration of the organic EL light emitting layer 1 is omitted in FIG. 1, for example, in order from the substrate 2 side, a TFT drive circuit layer, a reflective electrode, a hole injection layer, a hole transport layer, a light emitting layer, It can be configured by laminating an electron transport layer, an electron injection layer, and a transparent electrode.

  Since the organic EL light emitting layer 1 deteriorates rapidly when exposed to moisture in the atmosphere, it needs to be sealed from the outside air. Therefore, the surface of the organic EL light emitting layer 1 is covered with a transparent sealing film 3 made of, for example, a SiN film formed by CVD. Hereinafter, the substrate on which the organic EL light emitting layer 1 and the sealing film 3 are formed is referred to as a “first substrate”. In FIG. 1, the first substrate 7 has a structure in which an organic EL light emitting layer 1 and a sealing film 3 are provided on a substrate 2.

  The first substrate 7 including the organic EL light emitting layer 1 and the sealing film 3 is further covered with a sealing substrate (hereinafter referred to as “second substrate”) 6 in order to block the organic layer from the outside air. Although the detailed illustration of the second substrate 6 is omitted in FIG. 1, for example, a color filter, a thin film device having a touch panel function, or the like may be formed on a hard transparent member such as glass.

  By filling the gap between the substrate 6 and the sealing film 3 with transparent resins (ultraviolet curable type, thermosetting type, etc.) 4 and 5 such as epoxy resin, the first substrate 7 and the second substrate 6 The distance between the two can be kept constant. As a result, the surface of the first substrate 7 and the surface of the second substrate 6 can be kept parallel, and reflection and refraction at the interface between them can be prevented.

  FIG. 2 is a diagram showing a schematic configuration of the organic EL display device 10 according to an embodiment of the present invention. FIG. 2A is a perspective view of the first substrate 11 through the second substrate 12 of the organic EL display device 10. It is a plane perspective view which shows a surface shape, (b) is sectional drawing of the organic electroluminescence display 10 shown to (a).

  As shown in FIG. 2, the organic EL display device 10 according to an embodiment of the present invention includes a display area 20 in which an image is displayed, a frame area 22 that is an area outside the display area 20, and electricity with external elements. Including a terminal region 23 in which terminals for performing a general connection are arranged, and the first substrate 11 and the second substrate 12 are bonded together via resins 14 and 15. 2 corresponds to the first substrate 7 having the organic EL light emitting layer 1 and the sealing film 3 shown in FIG. 1, and the second substrate 12 shown in FIG. This corresponds to the second substrate 6 shown.

  As shown in FIG. 2A, on the surface of the first substrate 11, a resin 14 having a relatively high viscosity before curing in the frame region 22 is formed in a frame shape, and a space surrounded by the resin 14. Inside, the resin 15 having a relatively low viscosity before curing is filled. Thus, since the resin 14 having a relatively high viscosity before curing surrounds the resin 15 having a relatively low viscosity before curing, the resin 15 having a relatively low viscosity flows out to the surroundings even before the curing. It is possible to spread the resin 15 uniformly on the surface of the first substrate 11 while preventing the above. Due to the difference in functions of the resins 14 and 15, the resin 14 having a relatively high viscosity before curing is hereinafter referred to as a “dam material”, and the resin 15 having a relatively low viscosity is hereinafter referred to as a “filler”. Called.

  For the process of bonding the first substrate 11 and the second substrate 12 using such a dam material 14 and the filler 15, refer to the manufacturing process of the conventional organic EL display device 50 shown in FIGS. To explain. 9 and 10 are a cross-sectional view and a plan view for explaining a manufacturing process of the conventional organic EL display device 50, respectively. This bonding step is performed in a chamber constituting a manufacturing apparatus (not shown).

  First, as shown in FIGS. 9A and 10A, a manufacturing apparatus (not shown) uses a dispenser or the like on the surface of the first substrate 51 (the surface of the sealing film 3 shown in FIG. 1). The material 54 is applied in the shape of a frame, and a large number of fillers 55 are dropped into the inside of the dam material 54 at equal pitches. As shown in FIG. 9 (a), the filler 55 is dropped in the form of dots because the dropped filler 55 takes a substantially spherical form due to its surface tension. This is because only the filler 55 can provide a volume sufficient to fill the inside of the dam material 54.

  Next, the manufacturing apparatus (not shown) decompresses the inside of the chamber to a high degree and aligns the first substrate 51 and the second substrate 52 with each other as shown in FIG. As shown in FIG. 2, the two substrates 51 and 52 are overlapped. As a result, the fillers 55 scattered in the dam material 54 are expanded, filling the gap between them, and filling the space surrounded by the substrates 51 and 52 and the dam material 54.

  Thereafter, the manufacturing apparatus (not shown) returns the atmospheric pressure in the chamber to atmospheric pressure, takes out the bonded substrates 51 and 52, and performs a curing process on the dam material 54 and the filler 55. In the curing process, for example, when an ultraviolet curable epoxy resin is used for the dam material 54 and a thermosetting epoxy resin is used for the filler 55, the dam material 54 is irradiated with ultraviolet rays through the transparent second substrate 52. After the curing, the bonding step is completed by further thermosetting the filler 55 in a heating furnace. In addition, in the case where an ultraviolet delayed curing type resin is used for each of the dam material 54 and the filling material 55, both the substrates 54 and 55 are irradiated with ultraviolet rays before the both substrates 51 and 52 are bonded to each other. Since the curing of each of the resins 54 and 55 starts after the time when the 51 and 52 are bonded together, the curing can be completed in the curing furnace. The dam material 54 may be made of resin mixed with resin beads as a spacer.

  However, as shown in FIGS. 9D and 10B, if the filling material 55 does not spread smoothly, the gap between the dam material 54 and the two substrates 51 and 52 is not filled with the filling material 55, and the filling material 55 is filled. A portion not filled with the material 55 sometimes became a bubble (vacuum accumulation) 53. The reason why such bubbles 53 are formed is that the first substrate 51 is formed with the organic EL light emitting layer 1 (see FIG. 1) including the TFT drive circuit layer and the light emitting layer, and the second substrate 52 is colored. Since filters and the like are formed, it is considered that there are irregularities on the order of μm on the surfaces of both the substrates 51 and 52, and these irregularities become an obstacle to the wetting and spreading of the filler 55. Therefore, the present inventor fills the gap between the dam material 54 and both the substrates 51 and 52 with the filler 55 so as not to generate the bubbles 53, thereby improving the yield and improving the image quality. The manufacturing method of the display apparatus 10 was considered, and the manufacturing method of the organic EL display apparatus 10 which concerns on embodiment of this invention shown below was reached.

  Hereinafter, the bonding process of the first substrate 11 and the second substrate 12 will be described in more detail with respect to the manufacturing process of the organic EL display device 10 according to the embodiment of the present invention with reference to FIGS. 3, 5, and 6 are views for explaining a manufacturing process of the organic EL display device 10 according to an embodiment of the present invention, and FIG. 4 is a portion indicated by a broken line in FIG. It is an enlarged view of X. The detailed description of the same steps as those of the conventional organic EL display device 50 described above with reference to FIGS. 9 and 10 will be omitted.

  First, as shown in FIG. 3A, the dam material 14 is applied in a frame shape to the frame region 22 by a dispenser or the like on the surface of the first substrate 11 (the surface of the sealing film 3 illustrated in FIG. 1). A large number of fillers 15 are dropped into the inside of the dam material 14 at equal pitches.

  Next, the inside of the chamber is highly decompressed, and the first substrate 11 and the second substrate 12 are aligned with each other as shown in FIG. At this time, alignment of both substrates 11 and 12 is performed using alignment marks 30 and 31 as shown in FIG. FIG. 5A illustrates an example of the alignment mark 30 disposed on the second substrate 12, and FIG. 5B illustrates an example of the alignment mark 31 disposed on the first substrate 11. . The alignment marks 30 and 31 do not remain on the organic EL display device 10 as a product. The alignment marks 30 and 31 are formed on a mother substrate and are formed in a region to be removed after cutting, although not shown. The alignment marks 30 and 31 may be formed on the mother substrates of the first substrate 11 and the second substrate 12 using a metal film, a black matrix, or the like, and may be arranged at least two each.

  As shown in FIG. 5B, the alignment mark 31 arranged on the first substrate 11 includes a first alignment mark 31a and a second alignment mark 31b. As shown in FIG. 6A, the first alignment mark 31a disposed on the first substrate 11 and the alignment mark 30 disposed on the second substrate 12 are aligned, and then illustrated in FIG. 6B. As described above, the second alignment mark 31 b arranged on the first substrate 11 and the alignment mark 30 arranged on the second substrate 12 are aligned. As described above, first, the alignment mark 30 is aligned with the first alignment mark 31a, and the first substrate 11 and the second substrate 12 are overlapped at a position where the filler 14 is in contact with both the substrates 11 and 12, and then one of the substrates. Is moved in the horizontal direction so that the alignment mark 30 is aligned with the second alignment mark 31a, so that the substrates 11 and 12 can be bonded to each other at a desired position while the filler 14 is flowing.

  3B to 3E illustrate an example of a process of moving and bonding the second substrate 12 that is the upper substrate. As shown in FIG. 3B, the second substrate 12 is moved in a direction 1A perpendicular to the first substrate 11 to a position where the second substrate 12 contacts the filler 15, and as shown in FIG. Further, after aligning the alignment mark 30 arranged on the second substrate 12 with the first alignment mark 31a arranged on the first substrate 11 and superimposing the two substrates 11 and 12, as shown in FIG. Thus, the bonding process is completed by moving the second substrate 12 horizontally in the direction 1B to the position where the alignment mark 30 of the second substrate 12 is aligned with the second alignment mark 31b of the first substrate 11. As described above, first, the second substrate 12 is moved in the vertical direction with respect to the first substrate 11 and is superposed on the first substrate 11 via the filler 15, and then the second substrate 12 is placed on the first substrate 11. On the other hand, the filler 15 can be made to flow in the horizontal direction by moving it to a desired position in the horizontal direction. Therefore, it is possible to insert the filler 15 into the concavo-convex portions that can be formed on the surfaces of the substrates 11 and 12 and the gap between the substrates 11 and 12 and the dam material 14. Thereby, as illustrated in FIG. 3E, the gap between the two substrates 11, 12 and the dam material 14 can be filled with the filler 15, and the generation of the bubbles 53 can be prevented.

  Thereafter, the dam material 14 and the filler 15 are cured. Thereby, the dam material 14 after the bonding step is formed in a shape inclined in the same direction as the direction in which the second substrate 12 is moved, as shown in FIGS. That is, the dam material 14 has a shape including a portion inclined with respect to the horizontal plane of the first substrate 11 and the second substrate 12 on the surface connecting the portion in contact with the first substrate 11 and the portion in contact with the second substrate 12. Formed.

  Here, referring to FIG. 7 and FIG. 8 showing a schematic configuration of the conventional organic EL display device 50, as shown in FIG. 7B and FIG. , 12 does not have a cross-sectional shape inclined with respect to the horizontal plane, and it has a substantially symmetric cross-sectional shape with respect to an axis perpendicular to the horizontal plane of both substrates 11, 12. In the manufacturing process of the conventional organic EL display device 50, as shown in FIGS. 9B and 9C, the second substrate 52 is not moved in the horizontal direction but moved in the vertical direction 5A. This is because it is bonded to one substrate 51.

  On the other hand, as illustrated in FIG. 4, in the organic EL display device 10 according to an embodiment of the present invention, the dam material 14 is bonded to the first substrate 11 by moving the second substrate 12 in the horizontal direction. A portion of the dam material 14 in contact with the first substrate 11 and a portion of the dam material 14 in contact with the second substrate 12 are dragged by a distance moved in the direction in which the second substrate 12 is moved. An inclined surface is formed on the surface connecting the two.

  In the step of bonding the first substrate 11 and the second substrate 12 as described above, as shown in FIG. 3C, the shift amount when the second substrate 12 is shifted and overlapped with the first substrate 11. May be about 10 μm to 200 μm. The amount of displacement of the second substrate 12 with respect to the first substrate 11 is appropriately determined according to the specifications in consideration of the size of the irregularities on the surfaces of both the substrates 11 and 12, the final distance between the both substrates 11 and 12, and the like. Be changed.

  Further, as shown in FIG. 4, in the display device 10 of the present invention, the dam material 14 that is extended along with the movement of the second substrate 12 is finally disposed at a position that does not overlap the display region 20. Form. As shown in FIG. 8A, referring to the conventional display device 50, in the filler filling area filled with the filler 55, the display area 20, the dam material 54, In between, there is a frame-shaped blank area as illustrated as a blank width 21. In the manufacturing process according to an embodiment of the present invention, the second substrate 12 is placed within a range smaller than the margin width 21 so that the arrangement position of the dam material 14 is within the margin area shown in FIG. Move.

  Moreover, the direction at the time of moving the 2nd board | substrate 12 horizontally is not limited to the direction 1B shown in FIG.3 (d). FIG. 3 illustrates a case where the second substrate 12 is moved in a direction parallel to any two opposing sides of the four sides of the substantially rectangular dam material 14. However, it may be moved in a direction that is not parallel to the four sides of the substantially rectangular dam member 14. Further, the direction of movement of the substrate is not linear and may be rotated. Moreover, in the process shown in FIG. 3 mentioned above, although the process of moving the 2nd board | substrate 12 is shown, you may move the 1st board | substrate 11. FIG. In either case, either of the substrates 11 and 12 is moved in the horizontal direction, and the filler 15 and the dam material 14 are placed so that the filler 15 fills the gap between the substrates 11 and 12 and the dam material 14. By making it flow, generation | occurrence | production of the bubble 53 can be reduced.

  As described above, according to the manufacturing process of the organic EL display device 10 according to the embodiment of the present invention, after the first substrate 11 and the second substrate 12 are shifted and overlapped, the filler 15 is formed on both the substrates 11 and 11. By moving one of the substrates in the horizontal direction to the final bonding position in contact with 12, it is possible to prevent bubbles 53 from being generated in the filler 15. Therefore, according to the present invention, it is possible to manufacture the organic EL display device 10 that prevents the occurrence of display defects and improves the yield.

  As described above, according to the method for manufacturing the organic EL display device 10 according to the embodiment of the present invention, it is possible to provide the organic EL display device 10 with improved image quality while reducing the manufacturing cost by a simple manufacturing process. Can do.

10, 50 Organic EL display device 7, 11, 51 First substrate 6, 12, 52 Second substrate 4, 14, 54 Dam material (resin)
5, 15, 55 Filler (resin)
30, 31 Alignment mark 1 Organic EL light emitting layer 2 Substrate 3 Sealing film 20 Display area 22 Frame area 23 Terminal area 53 Bubble

Claims (6)

A first substrate including an organic EL light emitting layer;
A second substrate disposed opposite the first substrate;
A dam material disposed between the first substrate and the second substrate and outside a display region where the organic EL light emitting layer is disposed;
A filler filled in a space between the first substrate and the second substrate and the dam material,
The organic EL display device, wherein the dam material includes a portion inclined with respect to the surfaces of the first substrate and the second substrate.   2. The organic EL display device according to claim 1, wherein each of the dam material and the filler is a transparent resin, and the dam material is a resin having a higher viscosity before curing than the filler.   The organic EL display device according to claim 1, wherein the first substrate includes a terminal region in a region separated from the display region by the dam material. On the first substrate, an organic EL light emitting layer constituting a display region for displaying an image is formed,
Forming a sealing film on the first substrate on which the organic EL light emitting layer is formed;
A dam material surrounding the display area is disposed on the sealing film,
Place the filler inside the dam material,
After overlapping the first substrate and the second substrate with the dam material and the filler interposed therebetween, the first substrate or the second substrate is moved in the surface direction of the first substrate or the second substrate. Let
A method of manufacturing an organic EL display device, comprising: curing the dam material and the filler, and bonding the first substrate and the second substrate. The first substrate includes a plurality of first alignment marks outside the display area,
The second substrate includes a plurality of second alignment marks outside an area corresponding to the display area,
5. The organic EL display according to claim 4, wherein the first substrate and the second substrate are aligned and overlapped using the plurality of first alignment marks and the plurality of second alignment marks. Device manufacturing method.   By moving the first substrate or the second substrate in the horizontal direction, the dam material is connected to the surface that connects the portion in contact with the first substrate and the portion in contact with the second substrate, and the first substrate and 6. The method of manufacturing an organic EL display device according to claim 5, wherein the organic EL display device is formed to include a portion inclined with respect to each facing surface of the second substrate.

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