WO2015145966A1 - Organic el display panel, organic el display panel production method and organic el element sealing method - Google Patents

Abstract

Provided is an organic EL display panel having a lower base plate and an upper base plate that are disposed to be face-to-face, an organic EL element array region comprising a plurality of organic EL elements arrayed between the lower base plate and the upper base plate, a moisture absorption wall that is hygroscopic and surrounds the outer periphery of the organic EL element array region, and a sealing wall surrounding the periphery of the moisture absorption wall while sealing the gap between the lower base plate and the upper base plate. The planar shape of the moisture absorption wall has corner portions and edge portions. When a moisture absorption capacity is defined in the corner portion and the edge portion as the value from the division of the respective maximum moisture absorption amount by the respective length along the inner perimeter of the planar shape, the moisture absorption capacity of the corner portion is greater than the moisture absorption capacity of the edge portion.

Description

Organic EL display panel, organic EL display panel manufacturing method, and organic EL element sealing method

The present invention relates to an organic EL display panel in which organic EL (Electroluminescence) elements are arranged, and particularly to a sealing technique for organic EL elements.

In recent years, research and development have been conducted on organic EL display panels using light emission of organic EL elements as pixels. The organic EL element includes at least a pair of electrodes and an organic light emitting layer sandwiched between the electrodes, and emits light by energy of recombination of holes and electrons supplied from the electrodes. An organic EL display panel in which a plurality of such organic EL elements are arranged is superior in response, viewing angle, contrast ratio, weight reduction, and the like as compared with a liquid crystal display panel.

Here, a material having high activity with respect to moisture and oxygen is often used for the organic EL element, and therefore, the organic EL element easily reacts with moisture and oxygen in the air and deteriorates easily. Therefore, in an organic EL display panel, a sealing technique that suppresses contact between the organic EL element and the outside air is important.

In the sealing of the organic EL display panel, the upper and lower sides of the organic EL element arrangement region where a plurality of organic EL elements are arranged are sealed with a pair of substrates made of glass or the like, and are made of a curable resin or glass frit. In general, the sealing wall surrounds the outer periphery of the organic EL element arrangement region and seals the gap between the substrates. In addition, in the above structure, intrusion of outside air from the outer peripheral side may not be sufficiently suppressed, for example, a hygroscopic wall containing a hygroscopic material such as calcium or magnesium is used as the organic EL element arrangement region and the sealing wall. The structure arrange | positioned between these is disclosed (for example, refer patent document 1). In the organic EL display panel, it is necessary to make the sealing wall as close as possible to the organic EL element arrangement region in order to obtain a frame and to ensure the strength. It is necessary to be disposed in the vicinity of the EL element array region. For example, in patent document 1, the moisture absorption wall (desiccant 9) is arrange | positioned along the outer periphery of the organic EL element arrangement | sequence area | region (light emitting element 3), The shape is a rectangular shape. That is, the planar shape of the hygroscopic wall has corners.

JP 2007-73459 A

The inventor of the present application, for example, in the planar shape of a moisture absorbing wall having a corner, such as the above-described rectangular shape, has a moisture absorption rate (amount of moisture absorbed per unit volume / time) at another corner (hereinafter referred to as “side portion”). "). For example, as shown in FIG. 11, a moisture absorption wall 909 (shaded portion in the figure) surrounding the organic EL element arrangement region 905 in a rectangular shape along the outer periphery (two-dot chain line in the drawing) of the organic EL element arrangement region 905 is provided. In the organic EL display panel 90, the moisture absorption rate at the corner portion 909b is larger than that of the side portion 909a of the moisture absorption wall 909. Therefore, in the organic EL display panel 90, the hygroscopic capability of the corner portion 909b is saturated first when the hygroscopic capability of the side portion 909a remains.

When the hygroscopic capacity is saturated even in a part of the hygroscopic wall 909, moisture and oxygen in the outside air enter the organic EL element array region 905 from the part, and deteriorate the organic EL element. That is, in the organic EL display panel 90, the organic EL element is deteriorated before the moisture absorbing ability of the moisture absorbing wall 909 is sufficiently exhibited, and the expected life improvement effect cannot be obtained.

Accordingly, an object of the present invention is to provide an organic EL display panel in which the deterioration of the organic EL element due to saturation of the partial moisture absorption capacity of the moisture absorbing wall is reduced, a method for manufacturing such an organic EL display panel, and a method for sealing the organic EL element Is to provide.

An organic EL display panel according to one embodiment of the present invention includes a first substrate, a second substrate disposed opposite to the first substrate, and a plurality of organic substrates disposed between the first substrate and the second substrate. An organic EL element arrangement region in which EL elements are arranged. In addition, the organic EL display panel has a hygroscopic property, a moisture absorbing wall that surrounds the outer periphery of the organic EL element arrangement region between the first substrate and the second substrate, and a first substrate that surrounds the outer periphery of the moisture absorbing wall. And a sealing wall that seals a gap with the second substrate. Further, in the organic EL display panel, the planar shape of the moisture absorbing wall has at least one corner and a side that is a portion other than the corner. And in the said organic EL display panel, when the value which divided each maximum moisture absorption amount in a corner | angular part and a side part with the length of the inner periphery in each planar shape is made into a moisture absorption capacity | capacitance, the moisture absorption capacity | capacitance of a corner | angular part is a side. It is larger than the moisture absorption capacity of the part.

In the corner part of the moisture absorption wall of the organic EL display panel according to the above aspect, the moisture absorption capacity is larger than that of the side part, so even when the moisture absorption rate of the corner part is larger than that of the side part, it is between the side part and the corner part. It is possible to reduce a difference in time when the moisture absorption capacity is saturated. Therefore, the deterioration of the organic EL element due to saturation of the partial hygroscopic ability of the hygroscopic wall is reduced.

1 is a block diagram illustrating a configuration of an organic EL display device 1. FIG. 4 is a schematic plan view showing a part of the configuration of the organic EL display panel 10. FIG. 2A is a schematic cross-sectional view taken along line XX in FIG. 2, and FIG. 2B is a schematic cross-sectional view taken along line YY in FIG. (A) is a schematic plan view illustrating a method of forming the side portion 109a, (b) is a schematic plan view illustrating a method of forming the corner portion 109b, and (c) illustrates a method of forming the corner portion 109b. It is a model perspective view to do. It is a schematic plan view which shows the structure of the moisture absorption wall 209 which concerns on a modification. It is a schematic plan view which shows the structure of the moisture absorption wall 209W which concerns on a modification. It is a schematic plan view which shows the structure of the sealing wall 210 which concerns on a modification. It is a schematic plan view which shows the structure of the moisture absorption wall 209X and the sealing wall 210X which concern on a modification. (A) is a schematic plan view showing a configuration of a hygroscopic wall 209Y according to a modification, and (b) is a schematic cross-sectional view taken along the line ZZ in FIG. 9 (a). It is a schematic cross section which shows the structure of the moisture absorption wall 209Z which concerns on a modification. It is a schematic plan view which shows the structure of the organic electroluminescent display panel 90 which concerns on a prior art. It is a graph which shows the moisture absorption rate in the side part 909a and the corner | angular part 909b of the moisture absorption wall 909. FIG.

<Background to the Aspect of the Present Invention>
The inventor of the present application (hereinafter referred to as “the present inventor”) has found that the moisture absorption rate at the corners is larger than the moisture absorption rate at the sides in the planar shape of the moisture absorption wall having corners. The details are shown below.

FIG. 11 is a schematic plan view showing the configuration of the organic EL display panel 90. In the organic EL display panel 90, a plurality of organic EL elements are arrayed, and an organic EL element array region 905 having a rectangular outer periphery (two-dot chain line in FIG. 11) is divided into a lower substrate 901, an upper substrate 908, a moisture absorbing wall 909, It is sealed with a sealing wall 910. Note that the upper surface of the organic EL element array region 905 corresponds to the display region 91, and the organic EL display panel 90 includes a drive circuit 92 around the display region 91.

The lower substrate 901 and the upper substrate 908 are flat members that seal the lower and upper portions of the organic EL element array region 905, respectively. The sealing wall 910 seals the gap between the lower substrate 901 and the upper substrate 908 and maintains the sealing structure. The hygroscopic wall 909 has hygroscopicity, and adsorbs moisture, oxygen, and the like that have entered from the sealing wall 910, thereby suppressing moisture and oxygen from entering the organic EL element array region 905. The organic EL display panel 90 includes a sealing layer 906 in addition to the above components. The sealing layer 906 prevents contact between the organic EL element array region 905 and the outside air before the sealing structure is formed, and hydrogen and oxygen contained in members in the sealing structure after the sealing structure is formed are arranged in the organic EL element array. In order to prevent contact with the region 905, the upper surface and side surfaces of the organic EL element array region 905 are covered.

In the organic EL display panel 90, the moisture absorbing wall 909 surrounds the organic EL element array region 905 in a rectangular shape along the outer periphery of the organic EL element array region 905. The inventor measured the moisture absorption rate for each of the side part 909a corresponding to the rectangular side formed by the moisture absorption wall 909 and the corner part 909b corresponding to the corner. Specifically, the moisture absorption rate is set to the distance at which moisture permeates from the outer periphery of the moisture absorption wall 909 per hour, and the region of the moisture absorption wall 909 containing calcium oxide powder as a desiccant is observed with an optical microscope. Thus, the penetration distance was measured. In the measurement, the organic EL display panel 90 was performed under accelerated conditions of high temperature and high humidity (60 ° C., 90%).

FIG. 12 is a graph showing the measurement results of the moisture absorption rate at the side portions 909a and the corner portions 909b of the moisture absorption wall 909. The horizontal axis is time (unit: day), and the vertical axis is the moisture penetration distance (unit: μm) from the outer periphery of the moisture absorbing wall 909. As shown in the figure, the average moisture absorption rate of the corner portion 909b was 15.4 μm / day, which was nearly twice the average moisture absorption rate of the side portion 909a of 8.5 μm / day.

The present inventor considered that the difference in the moisture absorption rate was caused by the following two points. One is that the direction in which moisture and oxygen enter the outside air is one direction at the side portion 909a, but two directions at the corner portion 909b, and the surface area on the outside air per unit volume increases. is there. The other is that the corners 909b and the sealing wall 910 have less adhesive strength between the lower substrate 901 side and the upper substrate 908 side than the sides of the side portion 909a and the sealing wall 910, and moisture does not flow. It is because it is easy to invade.

Due to such a difference in moisture absorption rate, in the organic EL display panel 90, the moisture absorption capability of the corner portion 909b is saturated first when the moisture absorption capability of the side portion 909a remains. When the hygroscopic capacity is saturated even in a part of the hygroscopic wall 909, moisture and oxygen in the outside air enter the organic EL element array region 905 from the part, and deteriorate the organic EL element. That is, in the organic EL display panel 90, the organic EL element is deteriorated before the moisture absorbing ability of the moisture absorbing wall 909 is sufficiently exhibited, and the expected life improvement effect cannot be obtained.

From the above causes, the difference in moisture absorption speed is not limited to the case where the organic EL element array region is enclosed in a rectangular shape like the moisture absorption wall 909, but is considered to occur if the moisture absorption wall has at least one corner on the outer periphery. .

From the above circumstances, the present inventor has arrived at one aspect of the present invention described below in order to reduce the deterioration of the organic EL element due to saturation of the partial hygroscopic ability of the hygroscopic wall.

<Outline of Aspects of the Present Invention>
An organic EL display panel according to one embodiment of the present invention includes a first substrate, a second substrate disposed opposite to the first substrate, and a plurality of organic substrates disposed between the first substrate and the second substrate. An organic EL element arrangement region in which EL elements are arranged. In addition, the organic EL display panel has a hygroscopic property, a moisture absorbing wall that surrounds the outer periphery of the organic EL element arrangement region between the first substrate and the second substrate, and a first substrate that surrounds the outer periphery of the moisture absorbing wall. And a sealing wall that seals a gap with the second substrate. Further, in the organic EL display panel, the planar shape of the moisture absorbing wall has at least one corner and a side that is a portion other than the corner. And in the said organic EL display panel, when the value which divided each maximum moisture absorption amount in a corner | angular part and a side part with the length of the inner periphery in each planar shape is made into a moisture absorption capacity | capacitance, the moisture absorption capacity | capacitance of a corner | angular part is a side. It is larger than the moisture absorption capacity of the part.

Further, in the organic EL display panel according to one aspect of the present invention, in the above aspect, when the interval between the inner periphery and the outer periphery of the moisture absorption wall is a width, the width of the corner is larger than the width of the side.

In the corner part of the moisture absorption wall of the organic EL display panel according to the above aspect, the moisture absorption capacity is larger than that of the side part, so even when the moisture absorption rate of the corner part is larger than that of the side part, it is between the side part and the corner part. It is possible to reduce a difference in time when the moisture absorption capacity is saturated. Therefore, the deterioration of the organic EL element due to saturation of the partial hygroscopic ability of the hygroscopic wall is reduced.

Further, in the organic EL display panel according to one aspect of the present invention, in the above aspect, the width of the corner is twice or more than the width of the side. In the organic EL display panel according to the above aspect, it is possible to prevent the moisture absorption capability at the corners of the moisture absorption wall from being saturated before the side portions.

Further, in the organic EL display panel according to one aspect of the present invention, the corner portions protrude outward from the side portions in the planar shape of the moisture absorption wall according to the above aspect.

Further, in the organic EL display panel according to one aspect of the present invention, in the above aspect, the inner periphery of the moisture absorption wall has a shape along the outer periphery of the organic EL element arrangement region.

In the organic EL display panel according to the above aspect, the moisture absorption capacity at the corners can be improved without affecting the formation region of the organic EL element arrangement region, and a framed frame can be realized.

Further, in the organic EL display panel according to one aspect of the present invention, in the above aspect, the outer periphery of the sealing wall has a shape along the outer periphery of the moisture absorption wall. In the organic EL display panel according to the above aspect, it is possible to reduce moisture and oxygen permeability in the portion of the sealing wall along the corner. Thereby, in the said organic EL display panel, the moisture absorption speed | rate of a corner | angular part is reduced and the difference of the time when the moisture absorption capability between a side part and a corner | angular part is saturated can be reduced. Further, even when the drive circuit is arranged, a frame can be formed, and the ratio of the display area to the substrate size can be improved.

In the organic EL display panel according to one aspect of the present invention, in the above aspect, the outer periphery of the organic EL element array region is rectangular, and the outer periphery of the sealing wall is rectangular along the outer periphery of the organic EL element array region. Shape. The organic EL display panel according to the above aspect has a simple shape and can reduce the manufacturing cost.

Further, in the organic EL display panel according to an aspect of the present invention, in the above aspect, the height of the corner portion is larger than the height of the side portion.

Further, in the organic EL display panel according to one embodiment of the present invention, in the above embodiment, the hygroscopic wall is made of a resin containing a desiccant having hygroscopicity, and the content of the desiccant in the corner portion is in the side portion. It is larger than the content of the desiccant.

In the corner part of the moisture absorption wall of the organic EL display panel according to the above aspect, the moisture absorption capacity is larger than that of the side part, so even when the moisture absorption rate of the corner part is larger than that of the side part, it is between the side part and the corner part. It is possible to reduce a difference in time when the moisture absorption capacity is saturated. Therefore, the deterioration of the organic EL element due to saturation of the partial hygroscopic ability of the hygroscopic wall is reduced.

The method for manufacturing an organic EL display panel according to one aspect of the present invention includes a first substrate, a second substrate disposed to face the first substrate, and the first substrate and the second substrate. An organic EL device comprising: an organic EL device array region in which a plurality of organic EL devices are arrayed; and a sealing wall that surrounds an outer periphery of the organic EL device array region and seals a gap between the first substrate and the second substrate It is a manufacturing method of a display panel. Further, in the manufacturing method, a material having hygroscopicity is disposed on the main surface of the first substrate or the second substrate and inside the region where the sealing wall is disposed, and the planar shape has at least one corner portion. And a hygroscopic wall surrounding the outer periphery of the organic EL element array region so as to have a side portion other than the corner portion. Further, in the manufacturing method, when forming the moisture absorption wall, when the maximum moisture absorption amount at the corner and the side is divided by the length of the inner circumference in each planar shape, Is set larger than the moisture absorption capacity of the side portion.

According to the method for manufacturing an organic EL display panel according to the above aspect, it is possible to manufacture an organic EL display panel that can reduce the deterioration of the organic EL element due to partial saturation of the moisture absorption wall.

Further, in the organic EL element sealing method according to one embodiment of the present invention, both main surfaces of the organic EL element arrangement region in which a plurality of organic EL elements are arranged are respectively sealed with flat members. Further, in the sealing method, a material having hygroscopicity is disposed between the flat members, and the planar shape has at least one corner and a side that is a portion other than the corner. In this manner, a moisture absorbing wall surrounding the outer periphery of the organic EL element array region is formed. Furthermore, in the sealing method, the gap between the flat plate-like members is sealed so as to surround the region where the moisture absorption wall is disposed. And in the said sealing method, when forming the said moisture absorption wall, the value which divided each maximum moisture absorption amount in the said corner | angular part and the said side part by the length of the inner periphery in each planar shape is made into a moisture absorption capacity | capacitance. The moisture absorption capacity of the corner is set larger than the moisture absorption capacity of the side.

According to the method for sealing an organic EL element according to the above aspect, it is possible to reduce deterioration of the organic EL element due to saturation of the partial moisture absorption capability of the moisture absorption wall.

In the present application, “corners” and “rectangles” do not only indicate exact corners or rectangles, but also include slightly rounded corners, rectangles whose opposing sides are slightly out of parallel, and the like. . Further, the “planar shape” means a shape appearing in a plan (upper surface) view, specifically, a shape when the target member is projected on a plane parallel to the main surface of the first substrate or the second substrate. Point to. Furthermore, the “outer periphery” refers to the outer periphery in the planar shape.

<Embodiment>
Hereinafter, as an embodiment, an organic EL display device 1 including an organic EL display panel 10 which is one embodiment of the present invention will be described with reference to the drawings. The drawings of the present application are all schematic, and the scale of the members and the ratio between the vertical direction and the horizontal direction may be different from the actual ones.

1. Configuration of Organic EL Display Device 1 FIG. 1 is a block diagram showing the configuration of the organic EL display device 1. The organic EL display device 1 includes an organic EL display panel 10 and a control circuit 20 connected thereto. In the organic EL display panel 10, a rectangular display region 11 is disposed at the center, and a drive circuit 12 is disposed around the display region 11.

A plurality of organic EL elements (not shown) are arranged in the display area 11, and light is emitted from each organic EL element as a pixel, and an image is displayed in the display area 11. The drive circuit 12 includes a power supply circuit that supplies power to each organic EL element, a signal circuit that applies a voltage signal corresponding to a signal from the control circuit 20 to each organic EL element, and an organic that applies a voltage signal at regular intervals. It has a scanning circuit for switching EL elements and drives each organic EL element. The control circuit 20 converts data including image information input from the outside into a signal corresponding to the organic EL display panel 10, and outputs the signal to the drive circuit 12, thereby displaying an image to be displayed in the display area 11. Control.

2. Configuration of Organic EL Display Panel 10 (1) Overall Configuration The overall configuration of the organic EL display panel 10 will be described with reference to FIGS. FIG. 2 is a schematic plan view showing a part of the configuration of the organic EL display panel 10 (hereinafter referred to as “panel 10”). 3A is a schematic cross-sectional view taken along the line XX of FIG. 2, and FIG. 3B is a schematic cross-sectional view taken along the line YY of FIG.

As shown in FIGS. 2 and 3, the panel 10 is disposed between the lower substrate 101, the upper substrate 108 disposed opposite to the lower substrate 101, and between the lower substrate 101 and the upper substrate 108. The organic EL element arrangement | sequence area | region 105 by which the outer periphery 105a became rectangular shape. The organic EL element array region 105 is a region where a plurality of organic EL elements are arrayed. Here, the lower substrate 101 and the upper substrate 108 are one mode of the first substrate and the second substrate in this embodiment. In addition, the upper and lower sides of the board | substrate in the above are for convenience of explanation, Comprising: The upper and lower sides of the panel 10 are not limited.

Further, the panel 10 surrounds the outer periphery 105a of the organic EL element arrangement region 105 between the lower substrate 101 and the upper substrate 108, and surrounds the outer periphery 109d of the moisture absorption wall 109, and the lower substrate 101 and the upper substrate 108. And a sealing wall 110 for sealing the gap. As shown in FIGS. 3A and 3B, in the panel 10, a sealing layer 106 is disposed so as to cover the upper surface and side surfaces of the organic EL element arrangement region 105, and further on the sealing layer 106. A resin layer 107 is disposed.

The panel 10 employs an active matrix method, and includes a TFT layer 102 on the lower substrate 101 in which thin film transistor (TFT) elements that control current supplied to the organic EL elements are arranged. The panel 10 also includes a wiring portion 103 that connects the TFT element and an external circuit (drive circuit 12), and an interlayer insulating layer 104 formed on the TFT layer 102. The panel 10 employs a top emission method, and the upper substrate 108 side is used as an image display surface.

(2) Explanation of each part a. Lower substrate 101
The lower substrate 101 is a flat plate-like member that seals the lower side of the organic EL element arrangement region 105 and supports the laminate in the panel 10.

b. TFT layer 102
The TFT layer 102 is a layer in which a pixel drive circuit including a TFT element (not shown) is formed, and is disposed on the main surface of the lower substrate 101.

c. Wiring unit 103
The wiring portion 103 is a layer in which a wiring for electrically connecting the TFT element in the TFT layer 102 and an external circuit (drive circuit 12) is formed. As shown in FIG. It is pulled out from the side to the outside of the sealing wall 110.

d. Interlayer insulating layer 104
The interlayer insulating layer 104 is a layer that prevents unnecessary energization between the TFT layer 102 and the organic EL element array region 105, and is a layer that flattens unevenness on the lower substrate 101 due to the TFT layer 102. It is formed so as to cover the layer 102. The interlayer insulating layer 104 has a contact hole (not shown) for electrically connecting the TFT element in the TFT layer 102 and the organic EL element in the organic EL element arrangement region 105 corresponding to the TFT element. Is formed.

e. Organic EL element array region 105
The organic EL element arrangement area 105 is a layer in which a plurality of organic EL elements are arranged, and the upper surface thereof corresponds to the display area 11. Therefore, as indicated by a two-dot chain line in FIG. 2, the outer periphery 105a of the organic EL element arrangement region 105 is rectangular. In the panel 10, the organic EL elements are arranged in a two-dimensional direction along the upper surface of the lower substrate 101.

The organic EL element includes at least a pair of electrodes and an organic light emitting layer containing an organic material sandwiched between the electrodes, and emits light by recombination of holes and electrons supplied from the pair of electrodes in the organic light emitting layer. To do. The amount of light emitted from each organic EL element is determined by the supply current controlled by the corresponding TFT element. The organic EL element may have a hole / electron injection layer, a hole / electron transport layer, a hole / electron blocking layer, and the like. Contributes to light emission and long life.

In addition to the organic EL elements, the organic EL element array region 105 includes partition walls (not shown) for partitioning the organic EL elements, wirings (not shown) connected to the electrodes of the organic EL elements, and the like. Yes.

f. Sealing layer 106
The sealing layer 106 has a high sealing property, and moisture and oxygen contained in the sealing structure such as the resin layer 107, the upper substrate 108, and the moisture absorption wall 109 after the sealing structure is formed are organic EL element array regions 105. It is a layer that prevents contact with the surface. Further, the sealing layer 106 may be used as a layer for preventing the organic EL element array region 105 from coming into contact with outside air before forming a sealing structure at the time of manufacture.

The sealing layer 106 covers not only the upper and outer periphery 105a of the organic EL element array region 105 but also the interlayer insulating layer 104 and the TFT layer 102 which are the underlying layers, and its end surface is the upper surface of the lower substrate 101 (partially It is arranged on the wiring part 103 on the lower substrate 101 (FIGS. 3A and 3B). By adopting the above structure, a sealing structure that surrounds all directions of the organic EL element array region 105 is formed by the lower substrate 101 (and the wiring portion 103) having a low moisture and oxygen permeability and the sealing layer 106. can do. Since the panel 10 is a top emission type, the sealing layer 106 has translucency so as not to hinder the visibility of the display region 11 and is intermediate to the adjacent layers in the vertical direction. Has a refractive index.

g. Resin layer 107
The resin layer 107 is a layer that flattens the upper surface of the sealing layer 106 and fills a space surrounded by the sealing layer 106, the upper substrate 108, and the moisture absorbing wall 109 to disperse impacts from the outside. In addition, since the panel 10 is a top emission type, the resin layer 107 has translucency so as not to disturb the visibility of the display region 11, and further intermediate refraction with respect to an adjacent layer in the vertical direction. Have a rate.

h. Upper substrate 108
The upper substrate 108 is a flat plate-like member that seals above the organic EL element array region 105, and is disposed on the resin layer 107, the moisture absorbing wall 109, and the sealing wall 110. The upper substrate 108 has a low transmittance of moisture and oxygen so as to prevent intrusion of moisture and oxygen from the outside air, and has a high light transmittance so as not to disturb the visibility of the display region 11. preferable. The upper substrate 108 may be provided with a color filter that adjusts the emission color of the organic EL element.

i. Hygroscopic wall 109
The hygroscopic wall 109 has a hygroscopic property that adsorbs moisture, oxygen, and the like, and prevents moisture and oxygen entering from the outside air through the sealing wall 110 from coming into contact with the organic EL element array region 105, for example. As shown in FIG. 2, the moisture absorbing wall 109 has a substantially rectangular planar shape, a side portion 109 a along the outer periphery 105 a of the organic EL element array region 105, and a corner portion that protrudes outward from the side portion 109 a. 109b. Further, the inner periphery 109 c of the moisture absorbing wall 109 has a rectangular shape along the outer periphery 105 a of the organic EL element array region 105.

In the panel 10, when the maximum moisture absorption amount at the corner portion 109b and the side portion 109a is divided by the lengths Lb and La of the inner periphery 109c in the respective planar shapes as the moisture absorption capacity, as described later, the corner portion The moisture absorption capacity of 109b is larger than the moisture absorption capacity of the side 109a. Here, the maximum amount of moisture absorption refers to the maximum amount of moisture that can be absorbed by the moisture absorbing wall 109, for example, by a method based on “6.5 Method D” of “JIS K 7209: 2000 Plastic—How to Obtain Water Absorption Rate”. Can be measured.

Furthermore, in the panel 10, when the interval between the inner periphery 109c and the outer periphery 109d of the moisture absorbing wall 109 is the width, the width T2 of the corner portion 109b is more than twice the width T1 of the side portion 109a.

As shown in FIG. 3A, the side portion 109a is located on the inner side of the end portion of the sealing layer 106 and is disposed on the sealing layer 106. As shown in FIG. Are disposed over the lower substrate 101 from the sealing layer 106 beyond the end of the sealing layer 106. As described above, the panel 10 achieves a frame shape by bringing the moisture absorption wall 109 as close as possible to the organic EL element arrangement region 105.

j. Sealing wall 110
The sealing wall 110 is in close contact with the lower substrate 101 and the upper substrate 108 to seal the outer periphery 105a side of the organic EL element arrangement region 105 and as a spacer that maintains the sealing structure of the organic EL element arrangement region 105. Play a role. Therefore, it is preferable to have good adhesion to the lower substrate 101 and the upper substrate 108 and to have a certain rigidity. As shown in FIG. 2, the inner periphery 110c and the outer periphery 110d of the sealing wall 110 have a shape along the outer periphery 109d of the moisture absorbing wall 109, and protrude at positions corresponding to the corner portions 109b.

3A and 3B, in the panel 10, the outer periphery 110d side of the sealing wall 110 is outside the end of the sealing layer 106, and the lower substrate 101 and the sealing layer The interface with 106 is sealed. By doing in this way, penetration of moisture and oxygen from the interface can be suppressed.

(3) Material of each part The material of each part which comprises the panel 10 is demonstrated below. In addition, the material described below is an illustration and you may use the material which has the same function.

a. Lower substrate 101
For the lower substrate 101, a material having electrical insulation or a semiconductor material such as silicon can be used. Alternatively, a metal material such as stainless steel coated with a material having electrical insulating properties may be used. Examples of the electrically insulating material include alkali-free glass, soda glass, non-fluorescent glass, phosphoric acid glass, boric acid glass, quartz, acrylic resin, styrene resin, polycarbonate resin, epoxy resin, and polyethylene resin. Polyester resin, polyimide resin, silicone resin, aluminum oxide, and the like. In the panel 10, it is preferable to use a material having low permeability such as moisture and oxygen for the lower substrate 101 in order to seal the lower part of the organic EL element arrangement region 105.

b. TFT layer 102
The TFT layer 102 is formed by stacking a semiconductor, a conductor, and an insulator. Examples of semiconductors include silicon (amorphous, polycrystalline, etc.), oxide semiconductors such as indium-zinc-gallium oxide, and organic materials having a π-electron conjugated system extending in the planar direction, such as polycyclic aromatic compounds. Can be used. As the conductor, metals such as aluminum, copper, and gold, carbon such as graphite and carbon nanotube, and conductive oxides such as indium tin oxide (ITO) and indium zinc oxide (IZO) can be used. As the insulator, silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, acrylic resin, polyimide resin, siloxane resin, phenol resin, or the like can be used.

c. Wiring unit 103
For the wiring portion 103, a conductive material can be used. For example, the material exemplified as the conductor of the TFT layer 102 can be used.

d. Interlayer insulating layer 104
For the interlayer insulating layer 104, an electrically insulating patternable material, for example, an organic material such as an acrylic resin, a polyimide resin, a siloxane resin, or a phenol resin can be used.

e. Organic EL element array region 105
A conductive material can be used for the electrode and the wiring. For example, metals such as aluminum, silver, molybdenum, tungsten, titanium, chromium, nickel, and zinc, alloys such as neodymium-aluminum, gold-aluminum, and magnesium-silver, and conductive oxides such as ITO and IZO can be used. . Moreover, the multilayer structure etc. which laminated | stacked these may be sufficient. Since the panel 10 is a top emission type, the electrode and wiring on the lower substrate 101 side are made of a light reflective material, and the electrode and wiring on the upper substrate 108 side are made of a light transmissive material. It is preferable to use it.

An organic material that emits light by an electroluminescence phenomenon is used for the organic light emitting layer. Specifically, for example, oxinoid compounds, perylene compounds, coumarin compounds, azacoumarin compounds, oxazole compounds, oxadiazole compounds, perinone compounds, pyrrolopyrrole compounds, naphthalene compounds, anthracene compounds, fluorene compounds, fluoranthene compounds, tetracene compounds, pyrenes Compound, coronene compound, quinolone compound, azaquinolone compound, pyrazoline derivative, pyrazolone derivative, rhodamine compound, chrysene compound, phenanthrene compound, cyclopentadiene compound, stilbene compound, diphenylquinone compound, styryl compound, butadiene compound, dicyanomethylenepyran compound, dicyanomethylene Thiopyran compounds, fluorescein compounds, pyrylium compounds, thiapyrylium compounds, serenapyrine Compounds, telluropylium compounds, aromatic ardadiene compounds, oligophenylene compounds, thioxanthene compounds, cyanine compounds, acridine compounds, metal complexes of 8-hydroxyquinoline compounds, metal complexes of 2-bipyridine compounds, Schiff salts and group III metals Known fluorescent materials and phosphorescent materials such as fluorescent materials such as complexes, oxine metal complexes, and rare earth complexes (all described in JP-A-5-163488) can be used. Further, for example, a mixed layer of an organic compound using the above-described fluorescent substance or phosphorescent substance as a dopant may be used.

The partition wall can be made of a material having electrical insulation and capable of forming a fine pattern by processing. For example, the organic materials exemplified as the material for the interlayer insulating layer 104 can be used. In addition, it is preferable that the material of the partition wall has resistance to an organic solvent and does not excessively deform or alter the etching process or baking process. In the case of using a wet process for forming the organic light emitting layer, it is preferable that the surface of the partition wall is subjected to fluorine treatment or the like, or a material containing fluorine is used for the partition wall so as to have liquid repellency.

f. Sealing layer 106
For the sealing layer 106, an inorganic material such as silicon nitride, silicon oxide, silicon oxynitride, or aluminum oxide can be used as a material having low permeability such as moisture and oxygen.

g. Resin layer 107
For the resin layer 107, an organic material such as an epoxy resin, an acrylic resin, or a silicone resin can be used.

h. Upper substrate 108
As the upper substrate 108, for example, the material exemplified for the lower substrate 101 can be used.

i. Hygroscopic wall 109
For the moisture absorbing wall 109, a material having a hygroscopic property, for example, a chemical desiccant containing alkali metal or alkaline earth metal such as quick lime or calcium chloride, or a physical desiccant such as silica gel, aluminum oxide, or zeolite is epoxy-coated. What was contained in resin can be used.

j. Sealing wall 110
A material having good adhesion to the lower substrate 101 and the upper substrate 108 can be used for the sealing wall 110. Moreover, since the role as a spacer is given so that the sealing structure of the panel 10 may not be deformed by external pressure, a material having a certain rigidity can be mixed. For example, if the lower substrate 101 and the upper substrate 108 are glass materials or the like, a weldable glass frit can be used. Further, for example, various curable resins such as epoxy resin, urethane resin, and acrylic resin containing particles such as glass and resin can be used.

3. Method for Manufacturing Panel 10 An example of the method for manufacturing the panel 10 will be described below. In the following, the method for forming the moisture absorbing wall 109, which is a characteristic configuration of the present application, will be mainly described.

(1) Outline of production method a. Lower substrate preparation step First, the lower substrate 101 having the TFT layer 102, the wiring portion 103, and the interlayer insulating layer 104 formed on the upper surface is prepared. Specifically, for example, a thin film is first formed on the lower substrate 101 such as a glass substrate by using a sputtering method, a CVD (Chemical Vapor Deposition) method, a spin coating method, or the like. Then, the TFT layer 102, the wiring portion 103, and the interlayer insulating layer 104 are formed on the lower substrate 101 by patterning the thin film by a photolithography method or the like. At this time, plasma treatment, ion implantation, baking, or the like may be performed as necessary.

b. Organic EL Element Array Region Formation Step Next, an organic EL element array region 105 is formed on the lower substrate 101 on which the TFT layer 102, the wiring portion 103, and the interlayer insulating layer 104 are formed. Specifically, for example, a lower electrode is first formed on the lower substrate 101 by sputtering and photolithography. And the material which has photosensitivity is apply | coated uniformly, and a partition is formed by patterning this. Furthermore, after forming an organic light emitting layer between the partition walls by an inkjet method, an upper electrode is formed by a vacuum deposition method, thereby forming an organic EL element. Thereby, the organic EL element arrangement | sequence area | region 105 with which the some organic EL element was arranged is formed.

c. Sealing Layer Formation Step Next, the sealing layer 106 is formed so as to cover the organic EL element array region 105 and the outer periphery 105a. Specifically, a silicon nitride layer is formed in a necessary region on the lower substrate 101 on which the organic EL element array region 105 is formed by, for example, a CVD method. As shown in FIGS. 3A and 3B, in the panel 10, the sealing layer 106 is also formed at a position covering the side surfaces of the TFT layer 102 and the interlayer insulating layer 104. It is arranged on 101 and on the wiring part 103. This can be realized, for example, by arranging a mask on the lower substrate 101 in the CVD method and adjusting the opening position of the mask.

d. Moisture Absorbing Material / Sealing Material Application Step Next, on the lower surface side of the upper substrate 108, the moisture absorbing material 109 is made of a material for the moisture absorbing wall 109 so as to surround a position corresponding to the organic EL element array region 105 and the sealing layer 106. The material 109P is applied by, for example, a dispensing method, a printing method, a die coating method, or the like. At this time, the hygroscopic material 109P is projected outward at the corner 109b forming position than at the side 109a forming position. Details of such a coating method will be described later. Further, the sealing material 110P in which the material of the sealing wall 110 is pasted is applied onto the upper substrate 108 around the applied moisture absorbing material 109P by, for example, a dispensing method, a printing method, a die coating method, or the like.

e. Substrate Bonding Step Next, a resin material 107P such as an epoxy resin is applied on the lower surface side of the upper substrate 108 inside the region where the moisture absorbing material 109P and the sealing material 110P are applied. Then, on the lower substrate 101 that has undergone the above steps, the upper substrate 108 that has also undergone the above steps is disposed, and after applying an appropriate pressure, the sealing material 110P is cured or welded, and the lower substrate 101, the upper substrate 108, A sealing wall 110 for sealing the gap is formed. As a method of applying the pressure, a method of returning both substrates to an atmospheric pressure environment after bonding the lower substrate 101 and the upper substrate 108 formed under vacuum or reduced pressure can be used. Further, as a method for curing the sealing material 110P, thermosetting, photocuring, addition of a curing agent, or the like can be used. Note that in the case of using ultraviolet rays in photocuring, a delayed curable material is used for the sealing material 110P so that the laminate on the lower substrate 101 side is not affected, and ultraviolet rays are applied only to the upper substrate 108 before bonding. Irradiation is preferred. If the sealing material 110P is a glass frit, the sealing material 110P can be welded to the lower substrate 101 and the upper substrate 108 by a laser. At this time, if necessary, the resin material 107P and the moisture absorbent material 109P can be cured and welded to improve the adhesion to the upper substrate 108. Note that the resin material 107P and the hygroscopic material 109P become the resin layer 107 and the hygroscopic wall 109, respectively, by the bonding process, regardless of the presence or absence of curing / welding.

Thus, the panel 10 according to the present embodiment can be manufactured. In addition, the formation method of the organic EL element arrangement | sequence area | region 105 is not restricted to an inkjet method, For example, wet processes, such as a dispensing method, a nozzle coating method, intaglio printing, a relief printing, dry processes, such as a vacuum evaporation method, these dry processes And a wet process. Alternatively, a transfer method in which an organic material is transferred from a donor substrate may be used. Furthermore, the forming method of each member is not limited to the above method, and a known film forming method and patterning method can be used.

(2) Method of Applying Hygroscopic Material 109P The method of applying the hygroscopic material 109P in the method for manufacturing the panel 10 will be described with reference to FIG. 4A is a schematic plan view illustrating a method for forming the side portion 109a, FIG. 4B is a schematic plan view illustrating a method for forming the corner portion 109b, and FIG. 4C is a method for forming the corner portion 109b. It is a model perspective view explaining these. In FIG. 4, as an example, a method of applying the moisture absorbing material 109 </ b> P to the lower surface side of the upper substrate 108 using the dispensing method is described.

First, as shown in FIG. 4A, the nozzle N of the dispenser is moved at a constant speed at the position where the side 109a is formed. Thereby, the moisture absorbing material 109P can be applied with the uniform width T3 and the uniform thickness.

Next, as shown in FIG. 4B, when the position where the corner 109b is formed is reached, the moving speed of the nozzle is decreased. Thereby, the hygroscopic material 109P can be applied with a width T4 larger than T3. If it does in this way, hygroscopic material 109P can be made to project outside the corner 109b formation position rather than the side 109a formation position. Note that the application method using the dispenser is not limited to this, and the application width of the hygroscopic material 109P is not changed between the corner 109b formation position and the side 109a formation position, but the application height of the hygroscopic material 109P is increased. Good. Even in this case, the hygroscopic material 109P spreads in the width direction at the time of bonding, and thus the hygroscopic material 109P can be projected at the corner 109b formation position rather than the side 109a formation position.

At this time, in order to make the inner periphery 109c of the moisture absorbing wall 109 rectangular, the inside of the application region of the moisture absorbing material 109P may be aligned at the side 109a formation position and the corner 109b formation position. Specifically, as indicated by a line CL through which the center of the nozzle N in FIG. 4B passes, the nozzle N may be shifted outward at the corner 109b formation position.

Further, in order to make the width T2 of the corner 109b in the hygroscopic wall 109 more than twice the width T1 of the side 109a, the application width T4 of the hygroscopic material 109P at the corner 109b formation position is set to the side 109a formation. What is necessary is just to make it 2 times or more of application | coating width | variety T3 of the moisture absorbing material 109P of a position. This is because the widths T1 and T2 do not coincide with the widths T3 and T4 due to the spread of the hygroscopic material 109P due to the pressing of the upper substrate 108 and the volume change during curing, but the proportional relationship is maintained.

In addition, the application method of the hygroscopic material 109P is not limited to this. For example, the method shown in FIG. 4C can be used. Specifically, first, a stack up to the sealing layer 106 is formed on the lower substrate 101. Next, the sealing material 110 </ b> P is applied with a space from the sealing layer 106. At this time, the gap between the sealing layer 106 and the sealing material 110P is widened at a position corresponding to the corner 109b forming position from a position corresponding to the side 109a forming position. Next, if the hygroscopic material 109P is applied at the above interval, the hygroscopic material 109P can be protruded outward at the corner 109b formation position rather than the side portion 109a formation position.

In this method, the resin material 107P is preferably applied and cured after the sealing material 110P and the hygroscopic material 109P are applied. In particular, the resin material 107P, the hygroscopic material 109P, and the sealing material 110P are simultaneously cured. Is preferred. If the application and curing of the resin material 107P is performed before the application of the sealing material 110P and the moisture absorbing material 109P, the sealing material 110P and the moisture absorbing material 109P ride on the cured resin layer 107, so that This is because the flatness may be lowered.

In the above description, the dispensing method has been described. However, the method of applying the moisture absorbing material 109P is not limited to this, and various wet processes such as a printing method may be used.

4). Effect obtained (1) Effect due to difference in moisture absorption capacity In the panel 10, the moisture absorption capacity of the corner portion 109b is larger than the moisture absorption capacity of the side portion 109a. Specifically, in the panel 10, the corner portion 109b protrudes outside the side portion 109a, and the inner periphery 109c of the moisture absorption wall 109 has a rectangular shape along the outer periphery 105a of the organic EL element array region 105. The width of the portion 109b is larger than the width of the side portion 109a. At this time, in the corner portion 109b, the amount of the desiccant contained in the hygroscopic wall 109 is larger than that of the side portion 109a, corresponding to the width. Therefore, the moisture absorption capacity of the corner portion 109b is larger than the moisture absorption capacity of the side portion 109a.

That is, in the corner portion 109b, the moisture absorption speed is larger than that of the side portion 109a, but the moisture absorption capacity is also larger than that of the side portion 109a, thereby reducing the difference in time during which the moisture absorption capacity between the side portion 109a and the corner portion 109b is saturated. can do. Therefore, deterioration of the organic EL element due to saturation of the partial moisture absorption capability of the moisture absorption wall 109 is reduced.

(2) Other effects a. Effect by the width T2 of the corner portion 109b In the panel 10, the width T2 of the corner portion 109b is more than twice the width T1 of the side portion. As shown in FIG. 16, the corner portion 109b has a moisture absorption speed that is about twice that of the side portion 109a. Therefore, by setting the width T2 to be twice or more the width T1, the moisture absorption capacity of the corner portion 109b is increased. Can be prevented from being saturated before the side portion 109a.

b. Effect by Protruding Corner 109b In the panel 10, in the planar shape of the moisture absorbing wall 109, the corner 109b projects outward from the side 109a. At this time, as shown in FIGS. 3A and 3B, the portion protruding to the outside of the corner portion 109b can be disposed on the lower substrate 101, and from the side portion 109a on the sealing layer 106. In addition, the height of the moisture absorbing wall 109 (the length in the direction perpendicular to the lower substrate 101) can be increased. Thereby, in the corner portion 109b, the physical amount of the desiccant contained in the moisture absorbing wall 109 is increased and the moisture absorption capacity is improved as compared with the side portion 109a.

In particular, a laminate such as the TFT layer 102, the interlayer insulating layer 104, and the organic EL element array region 105 often has a forward tapered slope in the height direction at the outer peripheral portion, and the sealing layer 106 that covers these layers is also provided. It is common that it becomes a slope along the same shape. Therefore, when the moisture absorbing wall 109 is disposed close to the sealing layer 106 as in the panel 10, the moisture absorbing wall 109 is positioned on the slope, and the height of the moisture absorbing wall 109 is closer to the outer peripheral side than the inner peripheral side. Since it becomes large, the moisture absorption capacity | capacitance by the protrusion of the said corner | angular part 109b becomes large.

c. Effect by the shape of the outer periphery 110 d of the sealing wall 110 In the panel 10, the outer periphery 110 d of the sealing wall 110 has a shape along the outer periphery 109 d of the hygroscopic wall 109. At this time, the sealing wall 110 protrudes outward at a position along the corner portion 109b from a position along the side portion 109a.

Therefore, as shown in FIGS. 3A and 3B, the sealing wall 110 is disposed on the wiring portion 103 and the sealing layer 106 in the portion along the side portion 109 a of the sealing wall 110. In the portion along the portion 109 b, the sealing wall 110 can be disposed on the lower substrate 101. In general, the lower substrate 101 has higher adhesion to the sealing wall 110 and higher flatness than a laminate such as the wiring portion 103 and the sealing layer 106. Therefore, with the above configuration, in the sealing wall 110, moisture and oxygen permeability in a portion along the corner portion 109b can be reduced as compared with a portion along the side portion 109a.

Further, the protruding portion of the sealing wall 110 has a larger contact area with the base layer than the corners of the rectangular sealing wall 110 having no protrusion, and the adhesion with the base layer is improved. In general, in the rectangular sealing wall, the adhesion to the substrate is weaker at the corner than at the side, but with the above structure, the adhesion with the base layer is improved at the corner in the sealing wall 110. It is possible to reduce moisture and oxygen permeability in the corner portion.

As described above, in the panel 10, the moisture absorption speed of the corner portion 109b of the moisture absorption wall 109 is reduced, and the difference in time during which the moisture absorption capability between the side portion 109a and the corner portion 109b is saturated can be reduced.

Furthermore, as shown in FIG. 2, due to the protrusion of the portion along the corner 109 b of the sealing wall 110, the portion along the side 109 a of the sealing wall 110 is recessed inward, and the sealing wall 110 A space is formed outside the outer periphery 110d. In this case, for example, as shown in FIG. 2, the drive circuit 12 and the like can be arranged in the space. Thereby, in panel 10, the space which corner 109b protrudes, and the space where drive circuit 12 is arranged can be secured without waste. Therefore, the panel 10 can be framed after the drive circuit 12 is arranged, and the ratio of the display area to the substrate size can be improved.

5. The panel 10 which concerns on 1 aspect of this invention does not receive a limitation at all by the above embodiment except the essential characteristic component. Below, the modification of the panel 10 is demonstrated as an example of such a form. In addition, about the part similar to the said embodiment, the same code | symbol is attached | subjected and description is simplified or abbreviate | omitted.

(1) Inner peripheral shape of moisture absorption wall In the moisture absorption wall 109, the inner periphery 109c was a rectangle along the outer periphery 105a of the organic EL element arrangement | sequence area | region 105, However, The inner periphery shape of a moisture absorption wall is not restricted to this. FIG. 5 is a schematic plan view showing the configuration of the moisture absorbing wall 209 according to the modification.

The moisture absorbing wall 209 includes an outer periphery 109d having the same shape as the moisture absorbing wall 109, but the inner periphery 209c is not rectangular but has a shape along the outer periphery 109d.

Also in the moisture absorption wall 209, since the corner | angular part 209b protrudes outside rather than the side part 109a, it has an effect similar to the moisture absorption wall 109. FIG. Specifically, in the panel 10 including the moisture absorbing wall 209, the corner portion 209b can be disposed on the lower substrate 101 by the protrusion of the corner portion 209b, and the height of the corner portion 209b can be made larger than the side portion 109a. . Therefore, in the moisture absorption wall 209, the moisture absorption capacity of the corner part 209b can be made larger than the moisture absorption capacity of the side part 109a. That is, even in the panel 10 including the moisture absorption wall 209, the deterioration of the organic EL element array region 105 due to partial saturation of the moisture absorption capacity of the moisture absorption wall 209 is reduced.

In addition, when the inner peripheral shape of the moisture absorption wall 209 is used, the resin layer 207 can be filled into a space formed by the inner periphery 209c protruding outward at the corner portion 209b. Therefore, if a material having a hygroscopic capacity or a material having low permeability such as moisture or oxygen is used for the resin layer 207, even if the hygroscopic capacity is saturated first in the corner portion 209b, the organic EL element is deteriorated. Can be delayed.

(2) Projection shape of corner portion of moisture absorption wall In the moisture absorption wall 109, the projection shape of the corner portion 109b is rectangular, but the shape of the corner portion is not limited thereto. FIG. 6 is a schematic plan view showing the configuration of the moisture absorbing wall 209W according to the modification.

The moisture absorbing wall 209W includes a side portion 109a having the same shape as the moisture absorbing wall 109, but the protruding shape of the corner portion 209Wb is not a quadrilateral shape but a pentagonal shape. The inner periphery 209Wc of the moisture absorbing wall 209W has a shape along the outer periphery 209Wd. Moreover, the sealing wall 210W is arrange | positioned along the moisture absorption wall 209W, and the inner periphery 210Wc and the outer periphery 210Wd of the sealing wall 210W are shapes along the outer periphery 209Wd.

Also in the moisture absorption wall 209W, the corner portion 209Wb protrudes outward from the side portion 109a, and thus has the same effect as the moisture absorption wall 109. Specifically, in the panel 10 including the moisture absorbing wall 209W, the corner portion 209Wb can be disposed on the lower substrate 101 by the protrusion of the corner portion 209Wb, and the height of the corner portion 209Wb can be made larger than the side portion 109a. . Therefore, in the moisture absorption wall 209W, the moisture absorption capacity of the corner portion 209Wb can be made larger than the moisture absorption capacity of the side portion 109a. That is, even in the panel 10 including the moisture absorption wall 209W, the deterioration of the organic EL element arrangement region 105 due to the saturation of the partial moisture absorption capability of the moisture absorption wall 209W is reduced.

Here, similarly to the moisture absorbing wall 209, in the moisture absorbing wall 209W, it is also possible to fill the resin layer 207W in a space formed by the inner periphery 209Wc protruding outward at the corner portion 209Wb.

The protruding shape of the corners of the hygroscopic wall is not limited to the square shape of the hygroscopic walls 109 and 209 and the pentagonal shape of the hygroscopic wall 209W, and may be other polygonal shapes, arc shapes, combinations thereof, or the like. . Further, in the moisture absorbing wall whose corners are polygonal or arcuate, the inner periphery may be a shape along the outer periphery of the organic EL element arrangement region like the moisture absorbing wall 109, or the moisture absorbing walls 209 and 209W Thus, the shape along the outer periphery of the moisture absorption wall may be sufficient.

(3) Outer peripheral shape of sealing wall In the sealing wall 110, the outer periphery 110d is a shape along the outer periphery 109d of the hygroscopic wall 109, but the outer peripheral shape of the sealing wall is not limited thereto. FIG. 7 is a schematic plan view showing the configuration of the sealing wall 210 according to the modification.

The sealing wall 210 includes an inner periphery 110 c having the same shape as the sealing wall 110, but the outer periphery 210 d has a rectangular shape along the outer periphery 105 a of the organic EL element arrangement region 105. Also in the sealing wall 210, the hygroscopic wall 109 in which the hygroscopic capacity of the corner portion 109b is larger than the hygroscopic capacity of the side portion 109a can be disposed due to the shape of the inner periphery 210c. Therefore, even in the panel 10 including the sealing wall 210, the deterioration of the organic EL element array region 105 due to saturation of the partial moisture absorption capability of the moisture absorption wall 109 is reduced.

Note that, as shown in FIG. 7, the outer periphery 210d of the sealing wall 210 does not have a protruding portion, and thus the outer periphery of the upper substrate 208 can be rectangular without protruding. Thereby, the manufacture of the upper substrate 208 is simplified, and the manufacturing cost can be reduced.

(4) Width of corner portion In the moisture absorbing wall 109, the width T2 of the corner portion 109b is constant, but is not limited thereto. FIG. 8 is a schematic plan view showing the configuration of the hygroscopic wall 209X and the sealing wall 210X according to the modification. The hygroscopic wall 209 </ b> X and the sealing wall 210 </ b> X include the same inner periphery 109 c as the hygroscopic wall 109 and the same outer periphery 210 d as the sealing wall 210, respectively. On the other hand, the outer periphery 209Xd of the moisture absorption wall 209X changes so that the width continuously increases from the side portion 109a at the corner portion 209Xb. Further, the inner periphery 210Xc of the sealing wall 210X has a shape along the outer periphery 209Xd of the moisture absorption wall 209X.

Also in this structure, the width of the corner portion 209Xb is larger than the width of the side portion 109a, that is, the moisture absorption capacity of the corner portion 209Xb is larger than the moisture absorption capacity of the side portion 109a. Accordingly, even in the panel 10 including the hygroscopic wall 209X and the sealing wall 210X, the deterioration of the organic EL element arrangement region 105 due to partial saturation of the hygroscopic wall 109 is reduced.

(5) The space between the sealing layer, the moisture absorbing wall and the sealing wall The moisture absorbing wall 109 was in close contact with the sealing wall 110, but, like the moisture absorbing wall 209W in FIG. You may arrange | position the space | gap G (black part of FIG. 6). If the gap G is not disposed and the sealing layer and the moisture absorbing wall are brought into close contact with each other, the strength of the panel 10 as a whole is improved.

(6) Cross-sectional shape of the moisture absorbing wall As described above, the moisture absorbing wall 109 has the corner 109b protruding from the side 109a so that the height of the corner 109b is larger than the height of the side 109a. The method of increasing the size is not limited to this. FIG. 9A is a schematic plan view showing the configuration of the moisture absorbing wall 209Y according to the modification, and FIG. 9B is a schematic cross-sectional view taken along the line ZZ in FIG. 9A.

As shown in FIG. 9A, the moisture absorption wall 209Y includes an inner periphery 109c having the same shape as the moisture absorption wall 109, but the outer periphery 209Yd has a rectangular shape along the inner periphery 109c, similar to the moisture absorption wall 909. ing. As shown in FIG. 9B, the lower substrate 201Y has a recessed portion 201Ya that is recessed immediately below the corner portion 209Yb, and the sealing layer 206Y is disposed in the recessed portion 201Ya. Accordingly, the moisture absorbing wall 209Y can have a side portion 109a having the same shape as the moisture absorbing wall 109 and a corner portion 209Yb having a height higher than that of the side portion 109a. The sealing wall 210Y is disposed along the moisture absorbing wall 209Y, and the inner periphery 210Yc and the outer periphery 210d of the sealing wall 210Y have a shape along the outer periphery 209Yd.

Therefore, even in the panel 10 including the moisture absorbing wall 209Y, the deterioration of the organic EL element array region 105 due to saturation of the partial moisture absorbing ability of the moisture absorbing wall 209Y is reduced.

Note that moisture, oxygen, and the like adsorbed on the moisture absorption wall 209Y diffuse into the lower substrate 201Y side and the upper substrate 208 side while penetrating in the width direction. Therefore, the moisture absorption capacity of the moisture absorption wall 209Y is proportional not only to the width but also to the amount in the height direction.

From the above, the protruding direction of the corner of the moisture absorption wall is not limited to the lower substrate side, and may protrude to the upper substrate side. For example, the main surface may be processed to form a step at the position of the upper substrate corresponding to the corner of the moisture absorption wall, and a large amount of the moisture absorbent 109P may be applied at the corner formation position.

Further, the panel 10 may include a moisture absorbing wall having a shape in which the corner portion protrudes outside the side portion and also protrudes toward the upper substrate side or the lower substrate side by combining the shapes of the moisture absorbing wall 109 and the moisture absorbing wall 209Y. Good.

(7) Others Although the moisture absorption wall 109 has the side part 109a and the corner | angular part 109b, the component of the moisture absorption wall 109 is not restricted only to this. FIG. 10 is a schematic cross-sectional view illustrating a configuration of a moisture absorbing wall 209Z according to a modification. In addition, the cross section of FIG. 10 has shown the cross section of the same position as the cross section shown to Fig.3 (a).

The moisture absorbing wall 209Z has an upper portion 209Ze that covers the resin layer 107 in addition to the side portions 109a and the corner portions 109b. By having such an upper portion 209Ze, the moisture absorbing wall 209Z can adsorb moisture, oxygen, and the like contained in the resin layer 107, the upper substrate 108 (when a moisture-permeable member such as a color filter is disposed), and the like. Therefore, in the panel 10 provided with the hygroscopic wall 209Z, it is possible to reduce deterioration of the organic EL element array region 105 due to moisture and oxygen contained in the sealing structure.

In general, a material (particularly a desiccant) used for the moisture absorbing wall has a low light transmittance, and the light transmittance may change due to moisture absorption. Therefore, when the moisture absorbing wall 209Z is used, it is preferable to use the bottom emission method. .

Further, in the panel 10, the outer periphery 105a of the organic EL element array region 105 (display region 11) has a rectangular shape, but the shape of the organic EL element array region is not limited to this, and has a shape having at least one corner on the outer periphery. If it is. For example, it may be a polygonal shape such as a triangle or a pentagon. For example, the shape which combined the polygonal shape and the circular arc may be sufficient.

In the panel 10, the end of the sealing layer 106 reaches the lower substrate 101. However, the present invention is not limited to this. For example, the end of the sealing layer 106 is formed on the side surface (slope) of the TFT layer 102. It may be arranged. In this case, the moisture absorbing wall 109 is preferably disposed at a position covering the side surface of the TFT layer 102 exposed from the gap between the lower substrate 101 and the end of the sealing layer 106.

In addition, the panel 10 includes the sealing layer 106, but this is not an essential component and may have a configuration without the sealing layer 106. However, at this time, if the organic EL element arrangement region 105 and the moisture absorption wall 109 are in direct contact with each other, the organic EL element arrangement region 105 may be deteriorated by moisture or oxygen adsorbed on the inner periphery 109c side of the moisture absorption wall 109. Therefore, it is preferable to arrange a gap between the organic EL element arrangement region 105 and the moisture absorption wall 109.

In the organic EL display device 1 shown in FIG. 1, four drive circuits 12 are provided around the display area. However, the position and number of the drive circuits 12 are not limited to this, for example, only at one end of the display area. A drive circuit 12 may be disposed.

In addition, although the active matrix method and the top emission method are employed in the panel 10, a passive matrix method and a bottom emission method may be employed.

In addition, in the panel 10, in order to make the width T2 of the corner portion 109b larger than the width T1 of the side portion 109a, the corner portion 109b has a shape protruding outward from the side portion 109a. It is also possible to use other than the above. For example, the shape which the corner | angular part of a moisture absorption wall protrudes inside from a side part may be sufficient. On the other hand, when the inner periphery 109c of the moisture absorbing wall 109 has a shape along the outer periphery 105a of the organic EL element arrangement region 105 as in the panel 10, the ratio of the display region 11 to the substrate size can be further increased, and the frame is narrowed. Can be realized.

In addition, although the organic EL display panel has been described in this embodiment and the above-described modification, the sealing structure according to one embodiment of the present invention is useful in all electronic circuits using the semiconductivity of organic materials. For example, the sealing structure according to one embodiment of the present invention can be applied to organic EL lighting, organic TFT elements, organic photoelectric conversion elements, organic piezoelectric conversion elements, organic transistors, organic integrated circuits, and the like.

An organic EL display panel, a method for manufacturing an organic EL display panel, and a method for sealing an organic EL element according to the present invention include a device including a display device such as a television device, a commercial display, a personal computer, and a portable electronic device. Can be widely used.

10, 90 Organic EL display panel 11, 91 Display area 12, 92 Drive circuit (electronic circuit section)
101, 201Y, 901 Lower substrate (first and second substrates)
105, 905 Organic EL element array region 105a, 109d, 110d, 209Wd, 209Xd, 209Yd, 210d, 210Wd Outer periphery 108, 208, 908 Upper substrate (second, first substrate)
109, 209, 209W, 209X, 209Y, 209Z, 909 Hygroscopic wall 109a, 909a Side 109b, 209b, 209Wb, 209Xb, 209Yb, 909b Corner 109c, 110c, 209c, 209Wc, 210Wc, 210Xc, 210Yc 210, 210W, 210X, 210Y, 910 Sealing wall La, Lb Inner peripheral length T1, T2 Width

Claims (11)

A first substrate;
A second substrate disposed opposite the first substrate;
An organic EL element arrangement region in which a plurality of organic EL elements are arranged between the first substrate and the second substrate;
A hygroscopic wall having hygroscopicity and surrounding an outer periphery of the organic EL element arrangement region between the first substrate and the second substrate;
A sealing wall that surrounds an outer periphery of the moisture absorption wall and seals a gap between the first substrate and the second substrate;
With
The planar shape of the hygroscopic wall has at least one corner and a side that is a portion other than the corner,
When the value obtained by dividing the maximum amount of moisture absorption in the corner and the side by the length of the inner circumference in each planar shape is the moisture absorption capacity, the moisture absorption capacity of the corner is more than the moisture absorption capacity of the side. Is also big,
Organic EL display panel. When the interval between the inner periphery and the outer periphery of the hygroscopic wall is a width, the width of the corner portion is larger than the width of the side portion,
The organic EL display panel according to claim 1. The width of the corner is at least twice the width of the side,
The organic EL display panel according to claim 2. In the planar shape of the moisture absorbing wall, the corner portion protrudes outward from the side portion.
The organic EL display panel according to claim 1. The inner periphery of the moisture absorption wall is a shape along the outer periphery of the organic EL element arrangement region,
The organic EL display panel according to claim 4. The outer periphery of the sealing wall has a shape along the outer periphery of the moisture absorbing wall.
The organic EL display panel according to claim 4. The outer periphery of the organic EL element arrangement region is rectangular,
The outer periphery of the sealing wall has a rectangular shape along the outer periphery of the organic EL element arrangement region.
The organic EL display panel according to claim 4. The height of the corner is greater than the height of the side,
The organic EL display panel according to claim 1. The hygroscopic wall is made of a resin containing a desiccant having hygroscopicity,
The content of the desiccant at the corner is greater than the content of the desiccant at the side,
The organic EL display panel according to claim 1. An organic EL element arrangement region in which a plurality of organic EL elements are arranged between a first substrate, a second substrate arranged opposite to the first substrate, and the first substrate and the second substrate And a manufacturing method of an organic EL display panel comprising a sealing wall that surrounds an outer periphery of the organic EL element arrangement region and seals a gap between the first substrate and the second substrate,
On the main surface of the first substrate or the second substrate, a material having a hygroscopic property is disposed inside a region where the sealing wall is disposed, and the planar shape has at least one corner, Forming a moisture absorbing wall that surrounds the outer periphery of the organic EL element array region so as to have sides other than the corners;
When forming the hygroscopic wall, when the hygroscopic capacity is a value obtained by dividing each maximum hygroscopic amount at the corner and the side by the length of the inner circumference of each planar shape, the hygroscopic capacity of the corner Is set larger than the moisture absorption capacity of the side part,
Manufacturing method of organic EL display panel. Both main surfaces of the organic EL element arrangement region in which a plurality of organic EL elements are two-dimensionally arranged are sealed with flat members,
The organic EL device array is arranged such that a material having hygroscopicity is disposed between the flat members, and the planar shape has at least one corner and a side other than the corner. Forming a hygroscopic wall that surrounds the periphery of the region,
Sealing the gap between the flat plate-like members so as to surround the region where the moisture absorbing wall is disposed,
When forming the hygroscopic wall, when the hygroscopic capacity is a value obtained by dividing each maximum hygroscopic amount at the corner and the side by the length of the inner circumference of each planar shape, the hygroscopic capacity of the corner Is set larger than the moisture absorption capacity of the side part,
Organic EL element sealing method.

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