Display device

Abstract

To suppress the formation of cracks in a pixel area.SOLUTION: A display device 1 includes a substrate 101, an interlayer insulating layer 102 containing a resin material provided on one main surface 101c side of the substrate 101 and inside an outer edge 101e of the substrate 101, an organic EL array 160 including a plurality of organic EL elements 150 provided on the interlayer insulating layer 102, a bank portion 220 provided on one main surface 101c side of the substrate 101, outside the interlayer insulating layer 102 and inside the outer edge 101e of the substrate 101, and a sealing layer 108 provided continuously from on the organic EL array 160, on the interlayer insulating layer 102, and from on the bank portion 220 to the outer edge 101e of the substrate 101 or near the outer edge 101e so as to cover the organic EL array 160, the interlayer insulating layer 102, and the bank portion 220. The bank portion 220 has a cross-sectional shape that is convex in a direction opposite to the direction toward one main surface 101c of substrate 101.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present disclosure relates to a display device having a plurality of organic EL (Electro Luminescence) elements. [Background technology]

[0002] Conventionally, display devices having a plurality of organic EL elements are known. The organic EL element has a structure in which thin films of various materials are laminated, and includes a pixel electrode, a counter electrode, and an organic light-emitting layer located between these electrodes, which are formed above a TFT (thin film transistor) substrate. An electron transport layer and the like are also provided between the pixel electrode and the counter electrode. These layers may contain materials whose light-emitting characteristics deteriorate when they react with moisture. In order to suppress deterioration of the display quality of the display device, it is necessary to suppress the intrusion of moisture present in the external environment.

[0003] Patent Document 1 discloses a technique for preventing cracks that occur when dividing a plurality of organic EL devices from reaching the active region of the organic EL device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-98792 A Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, protruding structures are provided around the pixel region, which is an active region, and further, defects such as discontinuities are formed in advance near the base of the protruding structures. This stops the progression of cracks at the defect locations, and suppresses the formation of cracks in the pixel region. However, if discontinuous defects are formed around the entire periphery of the pixel region, there is a possibility that another crack will be generated due to the defect and that the crack will progress toward the pixel region. If a crack is formed in the pixel region, moisture will penetrate into the pixel region through the crack, degrading the display quality of the display device.

[0006] The present disclosure provides a display device capable of suppressing the formation of cracks in a pixel region. [Means for solving the problem]

[0007] One embodiment of a display device of the present disclosure comprises a substrate, an interlayer insulating layer containing a resin material provided on one main surface side of the substrate and inside the outer edge of the substrate, an organic EL array including a plurality of organic EL elements provided on the interlayer insulating layer, a bank portion provided on one main surface side of the substrate and outside the interlayer insulating layer and inside the outer edge of the substrate, and a sealing layer provided continuously from on the organic EL array, on the interlayer insulating layer and from on the bank portion to the outer edge or near the outer edge of the substrate so as to cover the organic EL array, the interlayer insulating layer and the bank portion, wherein the bank portion has a cross-sectional shape that is convex in a direction opposite to the one main surface of the substrate. Effect of the Invention

[0008] According to the display device of the present disclosure, it is possible to suppress the formation of cracks in the pixel region. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a plan view illustrating a display device of Comparative Example 1. [Diagram 2] 1 is a cross-sectional view of a portion of a display device of Comparative Example 1. FIG. [Diagram 3]FIG. 11 is a plan view illustrating a display device of Comparative Example 2. [Figure 4] 11 is a cross-sectional view of a portion of a display device of Comparative Example 2. FIG. [Diagram 5] 13 is a diagram illustrating a typical crack that occurs in the display device of Comparative Example 2. FIG. [Figure 6] 11 is a cross-sectional view of a portion of a display device of Comparative Example 3. FIG. [Figure 7] 1 is a plan view illustrating a display device according to an embodiment of the present invention; [Figure 8] 1 is a cross-sectional view of a portion of a display device according to an embodiment. [Figure 9] FIG. 1 is a schematic diagram showing a crack formed around a bank portion of a display device. [Figure 10] FIG. 4 is a schematic diagram showing an example of a direction in which a crack is formed. [Figure 11] FIG. 2 is a diagram showing a plurality of banks provided on the display device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (Background to this disclosure) The process leading to the present disclosure will be described with reference to Comparative Examples 1 to 3. In the present disclosure, a flexible display device that is repeatedly bent during use will be described as an example.

[0011] Fig. 1 is a plan view diagrammatically illustrating a display device 1001 of Comparative Example 1. Fig. 2 is a cross-sectional view of a portion of the display device 1001 of Comparative Example 1.

[0012] 1 shows a top view of a substrate 501, an organic EL array 560, a sealing layer 508, a polarizing plate 510, and the like included in the display device 1001. Fig. 2 shows a cross section taken along line II-II in Fig. 1.

[0013] The display device 1001 of Comparative Example 1 includes a substrate 501, an interlayer insulating layer 502, a pixel electrode 503, a bank 504, a light-emitting layer 505, a counter electrode 507, a sealing layer 508, an adhesive layer 509, and a polarizing plate 510. An organic EL element 550 is formed by the pixel electrode 503, the light-emitting layer 505, the counter electrode 507, etc. The pixel region of the display device 1001 is formed by an organic EL array 560 including a plurality of organic EL elements 550.

[0014] Substrate 501 is composed of base material 501a and TFT layer 501b formed on base material 501a. Sealing layer 508 has a three-layer structure in which first sealing layer 508a made of silicon nitride (SiN), second sealing layer 508b made of resin, and third sealing layer 508c made of silicon nitride are laminated.

[0015] In the display device 1001 of Comparative Example 1, the sealing layer 508 is entirely covered and reinforced with the polarizing plate 510. Therefore, even if the substrate 501 is bent, the sealing layer 508 does not crack, and the sealing performance of the pixel region can be maintained. However, in the display device 1001 of Comparative Example 1, the area of ​​the polarizing plate 510 needs to be large in order to cover the entire sealing layer 508. Therefore, there is a problem in that it is not possible to narrow the area outside the pixel region, that is, to narrow the frame of the display device 1001.

[0016] Fig. 3 is a plan view diagrammatically illustrating a display device 1002 of Comparative Example 2. Fig. 4 is a cross-sectional view diagrammatically illustrating a portion of the display device 1002 of Comparative Example 2. Fig. 5 is a diagram diagrammatically illustrating a crack occurring in the display device 1002 of Comparative Example 2.

[0017] In addition, Fig. 3 shows a top view of the substrate 501, the organic EL array 560, the sealing layer 508, and the polarizing plate 510 included in the display device 1002. Fig. 4 shows a cross section taken along the line IV-IV in Fig. 3. Fig. 5 shows an enlarged view of the V portion in Fig. 3.

[0018] 3 and 4, the size of the adhesive layer 509 and the polarizing plate 510 is smaller than the outer shape of the sealing layer 508. As shown in the figures, the outer edge of the polarizing plate 510 is located inside the outer edge of the sealing layer 508, so that the frame of the display device 1002 can be narrowed. However, since the outer edge of the sealing layer 508 is not protected by the polarizing plate 510, for example, when the display device 1002 is repeatedly bent during use, cracks will occur in the sealing layer 508 as shown in FIG. 5. If cracks are formed in the pixel region, moisture will enter the pixel region through the cracks, causing a problem of a decrease in the display quality of the display device 1002.

[0019] FIG. 6 is a cross-sectional view of a part of a display device 1003 of Comparative Example 3. As shown in FIG.

[0020] In the display device 1003 of Comparative Example 3, the protruding structures 522 are provided around the pixel region, and further, the defects 522f, which are like discontinuities, are formed in advance near the bases of the protruding structures 522. This stops the progression of the cracks at the locations where the defects 522f are formed, and suppresses the formation of cracks in the pixel region. However, in the display device 1003, which is repeatedly bent and deformed, if the defects 522f, which are like discontinuities, are formed, there is a possibility that another crack will be generated due to the defects 522f, and the crack will progress toward the pixel region. If a crack is formed in the pixel region, moisture will enter the pixel region through the crack, causing a problem that the display quality of the display device 1003 will deteriorate.

[0021] Therefore, in the present disclosure, the formation of cracks in the pixel region is suppressed by a structure different from that of Comparative Example 3. The display device of the present disclosure has the following configuration in order to suppress the formation of cracks in the pixel region.

[0022] Hereinafter, an embodiment of a display device according to the present disclosure will be described with reference to the drawings. Note that each of the embodiments described below shows a specific example of the present disclosure. Therefore, the numerical values, components, arrangement positions and connection forms of the components shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Therefore, among the components in the following embodiments, components that are not described in the independent claims will be described as optional components.

[0023] In each drawing, substantially the same components are denoted by the same reference numerals, and each drawing is a schematic view, and the size ratio of each part is not necessarily strictly represented.

[0024] In this specification, the X direction, Y direction, and Z direction in each drawing correspond to the row direction, column direction, and thickness direction, respectively, of the display device.

[0025] (Embodiment) [Display device configuration] The display device according to the embodiment will be described with reference to FIGS.

[0026] FIG. 7 is a plan view that illustrates a display device 1 according to the embodiment.

[0027] In addition, the figure shows a top see-through view of the substrate 101, the interlayer insulating layer 102, the organic EL array 160, the bank portion 220, the sealing layer 108, the polarizing plate 110, etc., which are included in the display device 1. The figure also shows a schematic diagram of the arrangement position and width of the bank portion 220.

[0028] 7 is an example of an organic EL display panel, and has a rectangular shape when viewed in a plan view from the Z direction. In this embodiment, a display device having flexibility and capable of being bent will be described as an example of a top-emission type display device that emits light from the top surface.

[0029] 8 is a cross-sectional view of a portion of the display device 1. In FIG. 8, a cross section taken along line VIII-VIII in FIG.

[0030] In the display device 1, an interlayer insulating layer 102 is formed on the upper side of a substrate 101, and an organic EL array 160 is formed on the upper side of the interlayer insulating layer 102. A sealing layer 108, an adhesive layer 109, and a polarizing plate 110 are laminated on the organic EL array 160 in this order.

[0031] The substrate 101 is composed of a base material 101a made of an insulating material and a TFT (Thin Film Transistor) layer 101b. A driving circuit made of TFTs is formed in the TFT layer 101b. The TFT layer is composed of, for example, a channel, a gate insulating layer, a gate electrode, a protective layer, a source electrode, a drain electrode, a passivation layer, and the like (not shown).

[0032] The display device 1 has a first region 10 including a pixel region of the display device 1, and a second region 20 located on the outer periphery of the first region 10. The first region 10 is a region including the TFT layer 101b of the substrate 101, and has a rectangular shape. The second region 20 is a region where the TFT layer 101b is not formed, and has a frame-like shape. In the second region 20, a plurality of wirings and terminals (not shown) are arranged for electrically connecting the TFT layer 101b to an external drive circuit.

[0033] In this example, the second region 20 corresponds to the outer peripheral region 101g of the substrate 101, and the first region 10 corresponds to a region inside the outer peripheral region 101g of the substrate 101. In this embodiment, the inside means the center side of the organic EL array 160 as viewed from the object to be compared, and the outside means the opposite side of the center side of the organic EL array 160 as viewed from the object to be compared.

[0034] When viewed from a direction perpendicular to the substrate 101, the first region 10 includes a part of the substrate 101, the interlayer insulating layer 102, the organic EL array 160, the bank 104, the metal layer 203, a part of the sealing layer 108, a part of the adhesive layer 109, and a part of the polarizing plate 110. The second region 20 includes a part of the substrate 101, a part of the sealing layer 108, a part of the adhesive layer 109, a part of the polarizing plate 110, and a bank portion 220.

[0035] The substrate 101 has one main surface 101c and the other main surface 101d facing away from the one main surface 101c. The display device 1 is formed by stacking a plurality of layers on the one main surface 101c of the substrate 101.

[0036] The display device 1 includes the above-mentioned substrate 101, the interlayer insulating layer 102, the organic EL array 160, the bank 104, the metal layer 203, the bank portion 220, the sealing layer 108, the adhesive layer 109, and the polarizing plate 110.

[0037] The interlayer insulating layer 102 is provided on one main surface 101c side of the substrate 101, inside the outer edge 101e of the substrate 101. Most of the interlayer insulating layer 102 is provided in the first region 10, but in this example, the outer peripheral edge of the interlayer insulating layer 102 extends into the second region 20. The interlayer insulating layer 102 is a layer formed of an insulating resin material. Examples of the resin material include acrylic resin, polyimide resin, siloxane resin, and phenol resin. The interlayer insulating layer 102 also serves to flatten steps formed by the TFT layer 101b.

[0038] The interlayer insulating layer 102 includes a lower interlayer insulating layer 102a and an upper interlayer insulating layer 102b. The lower interlayer insulating layer 102a is provided on the substrate 101. The upper interlayer insulating layer 102b is provided on the opposite side to the one main surface 101c side of the lower interlayer insulating layer 102a, i.e., above the lower interlayer insulating layer 102a.

[0039] A silicon nitride (SiNx) film 202 is provided between the lower interlayer insulating layer 102a and the upper interlayer insulating layer 102b. The silicon nitride film 202 is disposed so as to extend from between the lower interlayer insulating layer 102a and the upper interlayer insulating layer 102b to the second region 20. The silicon nitride film 202 is a film for protecting the TFT layer 101b, and is disposed on one main surface 101c of the substrate 101 in the second region 20. Note that another silicon nitride film may be provided between the substrate 101 and the silicon nitride film 202 in the second region 20.

[0040] The organic EL array 160 is provided on the interlayer insulating layer 102 and in the first region 10. The organic EL array 160 is formed by a plurality of organic EL elements 150 arranged in a matrix. For example, in the organic EL array 160, three sub-pixels are formed by three organic EL elements 150 corresponding to each color of RGB (red, green, blue), and one pixel is formed by combining these three sub-pixels. Note that each pixel is not limited to three sub-pixels, and may be formed by one sub-pixel of W (white) or four sub-pixels of RGBW. The pixel region of the display device 1 is constituted by the organic EL array 160 including the plurality of organic EL elements 150.

[0041] Each organic EL element 150 has a pixel electrode 103 , a light emitting layer 105 and a counter electrode 107 .

[0042] The pixel electrode 103 is an electrode that functions as an anode of the organic EL element 150. The pixel electrode 103 includes a metal layer made of a light-reflective metal material, and is formed on the interlayer insulating layer 102. The pixel electrode 103 is provided for each pixel, and is electrically connected to the TFT layer 101b via a connection electrode. The pixel electrode 103 may be composed of a single metal layer, or may have a structure in which multiple layers are stacked.

[0043] The light-emitting layer 105 is provided on the pixel electrode 103. The light-emitting layer 105 is made of a polymer material or a low molecular weight material. The light-emitting layer 105 is formed in the opening of the bank 104, and emits light of each color R, G, and B by recombination of holes and electrons.

[0044] The counter electrode 107 is an electrode that functions as a cathode of the organic EL element 150. The counter electrode 107 is made of a light-transmitting conductive material. For example, ITO or IZO is used as the material of the counter electrode 107. Note that the counter electrode 107 may be made of a thin metal film such as silver, a silver alloy, aluminum, or an aluminum alloy. Note that an electron transport layer or the like is formed between the light-emitting layer 105 and the counter electrode 107 (not shown).

[0045] The bank 104 has a frame-like partition shape, and is provided on the pixel electrode 103 so as to surround the light-emitting layer 105 and the counter electrode 107 of the organic EL element 150. The bank 104 is made of an insulating organic material such as an acrylic resin, a polyimide resin, a novolac resin, or a phenol resin.

[0046] The metal layer 203 is provided on a part of the interlayer insulating layer 102. The metal layer 203 is connected to the organic EL array 160 and disposed outside the organic EL array 160. The metal layer 203 is provided in the first region 10 and is not provided in the second region 20. The metal layer 203 is formed by, for example, a coating method, a sputtering method, a vacuum deposition method, or the like. The metal layer 203 includes at least one of an anode metal layer and a cathode metal layer.

[0047] The bank portion 220 is provided on one main surface 101c side of the substrate 101, outside the organic EL array 160, the bank 104, the metal layer 203 and the interlayer insulating layer 102, and inside the outer edge 101e of the substrate 101. The bank portion 220 is also disposed inside the outer peripheral edge 108e of the sealing layer 108. The bank portion 220 of the present embodiment is provided in the second region 20, and not in the first region 10. The configuration of the bank portion 220 will be described in detail later.

[0048] The sealing layer 108 has a function of protecting the organic EL array 160 and the like. The sealing layer 108 is provided continuously from the organic EL array 160, the metal layer 203, the interlayer insulating layer 102, and the bank portion 220 to the outer edge 101e of the substrate 101 so as to cover the organic EL array 160, the metal layer 203, the interlayer insulating layer 102, and the bank portion 220. Note that the sealing layer 108 does not need to be flush with the outer edge 101e of the substrate 101, and it is sufficient that the sealing layer 108 is provided up to the vicinity of the outer edge 101e of the substrate 101.

[0049] The sealing layer 108 is composed of a lower inorganic sealing layer 108a, a resin sealing layer 108b, and an upper inorganic sealing layer 108c, each of which is light-transmitting.

[0050] The lower inorganic sealing layer 108a is provided continuously from the organic EL array 160, the metal layer 203, the interlayer insulating layer 102, and the bank portion 220 to the second region 20 so as to cover the organic EL array 160, the metal layer 203, the interlayer insulating layer 102, and the bank portion 220. In other words, the lower inorganic sealing layer 108a is disposed in both the first region 10 and the second region 20. The lower inorganic sealing layer 108a is formed of a thin film of silicon nitride (SiN).

[0051] The resin sealing layer 108b is formed so as to cover a part of the lower inorganic sealing layer 108a. For example, the resin sealing layer 108b covers at least a part of the lower inorganic sealing layer 108a located on the organic EL array 160, the metal layer 203, and the interlayer insulating layer 102, and is provided up to the inner region of the outer periphery of the interlayer insulating layer 102. In other words, the resin sealing layer 108b is formed in the first region 10, but not in the second region 20. The resin sealing layer 108b is formed of, for example, a fluorine-based, acrylic-based, epoxy-based, or silicone-based resin.

[0052] The upper inorganic sealing layer 108c is provided continuously from the resin sealing layer 108b to the second region 20 so as to cover the resin sealing layer 108b and overlap the lower inorganic sealing layer 108a in the second region 20. That is, the upper inorganic sealing layer 108c is formed in both the first region 10 and the second region 20. The upper inorganic sealing layer 108c is formed of a thin film of silicon nitride (SiN). In this manner, the upper inorganic sealing layer 108c extends to the second region 20, and the outer end of the upper inorganic sealing layer 108c and the outer end of the lower inorganic sealing layer 108a are in close contact with each other.

[0053] The polarizing plate 110 is a sheet-like member that polarizes the light emitted from the organic EL element 150. The polarizing plate 110 also serves as a member that complements the sealing property of the pixel region. The polarizing plate 110 is formed of a light-transmitting material such as a transparent resin film. The polarizing plate 110 is provided on the sealing layer 108 so as to cover a part of the sealing layer 108. The outer peripheral end 110e of the polarizing plate 110 is located in the second region 20, specifically, located outside the interlayer insulating layer 102 and inside the outer peripheral end 108e of the sealing layer 108.

[0054] An adhesive layer 109 is provided between the polarizing plate 110 and the sealing layer 108. The adhesive layer 109 is a material for bonding the polarizing plate 110 to the sealing layer 108, and is formed of, for example, an acrylic resin having optical transparency. The polarizing plate 110 is aligned on the sealing layer 108 and adhered to the sealing layer 108 via the adhesive layer 109.

[0055] The reason why the size of the polarizing plate 110 is smaller than the outer shape of the sealing layer 108 is that, for example, if the outer shapes of the polarizing plate 110 and the sealing layer 108 are the same size, the polarizing plate 110 will protrude beyond the sealing layer 108 and a narrow frame cannot be achieved if misalignment occurs when bonding the polarizing plate 110 to the sealing layer 108. For this reason, the polarizing plate 110 is designed to be smaller than the outer shape of the sealing layer 108, and the outer peripheral edge 110e of the polarizing plate 110 is always located inside the outer peripheral edge 108e of the sealing layer 108.

[0056] The display device 1 according to the present embodiment has the following configuration in order to suppress the formation of cracks in the pixel region.

[0057] The bank portion 220 has a frame-like shape, and is provided in the second region 20 so as to surround the interlayer insulating layer 102. The bank portion 220 is located outside the outer circumferential edge 110e of the polarizing plate 110 in the second region 20.

[0058] The bank portion 220 has a structure including a lower bank layer 220a and an upper bank layer 220b formed on the lower bank layer 220a. The lower bank layer 220a is provided on the silicon nitride film 202 formed in the second region 20. The lower bank layer 220a is formed of the same material as the upper interlayer insulating layer 102b and is formed on the same layer as the upper interlayer insulating layer 102b. This layer is formed on the entire surface of the silicon nitride film 202, and then patterned using photolithography and etching techniques, and the lower bank layer 220a is formed into a trapezoidal shape as described below. The upper bank layer 220b is formed of the same material as the bank 104 and is formed on the same layer as the bank 104. This layer is patterned using photolithography and etching techniques, and the upper bank layer 220b is formed so as to cover the lower bank layer 220a. The bank portion 220 may be composed of only the lower bank layer 220a.

[0059] As shown in FIG. 8, the bank portion 220 has a trapezoidal cross section (transverse cross section) perpendicular to the extending direction of the bank portion 220. That is, the bank portion 220 has a tapered cross section that is convex in a direction opposite to the direction toward one main surface 101c of the substrate 101. For example, the bank portion 220 has an inclined surface at an angle of 45° or less with respect to an axis perpendicular to the protruding direction. The inclined surface is not limited to a flat surface, and may be curved. For example, the width of the bank portion 220 is 500 μm, and the height is 5.3 μm. The height dimension of the bank portion 220 is larger than the thickness dimension of the lower inorganic sealing layer 108a and is equal to or smaller than the height dimension of the upper interlayer insulating layer 102b.

[0060] FIG. 9 is a schematic diagram showing cracks formed around the bank portion 220 of the display device 1. As shown in FIG.

[0061] Fig. 9(a) shows a top view of the bank portion 220 in part IX in Fig. 7, and (b) shows an enlarged view of part IXb in (a). Fig. 9(c) shows a cross section taken along line IXc-IXc in (b), and (d) shows a cross section taken along line IXd-IXd in (b).

[0062] In the display device 1, cracks occur at the outer peripheral end 108e of the sealing layer 108 as the display device 1 is repeatedly bent during use. The cracks that occur at the outer peripheral end 108e of the sealing layer 108 reach the bank portion 220, as shown in (a) and (b) of Figure 9. (c) and (d) of Figure 9 show cross sections of cracks formed in the lower inorganic sealing layer 108a on the bank portion 220. As shown in these figures, the cracks do not pass completely through the bank portion 220, but remain on or around the bank portion 220.

[0063] FIG. 10 is a schematic diagram showing an example of a direction in which a crack is formed.

[0064] In the figure, broken arrows indicate cracks formed in the lower inorganic sealing layer 108a on the bank portion 220. In the figure, the bank portion 220 has an arched semi-cylindrical shape.

[0065] As shown in the figure, when a crack reaches the bank portion 220 from the outside, the direction of travel changes when it overcomes the bank portion 220. In this example, when the crack passes the top of the bank portion 220 and goes down the inclined surface, the direction of travel of the crack changes and the crack progresses along the extension direction of the bank portion 220. By providing the bank portion 220 in this way, the direction of travel of the crack generated at the outer peripheral end 108e of the sealing layer 108 can be changed so that the crack does not head toward the pixel region. Therefore, it is possible to suppress the formation of cracks in the pixel region. This makes it possible to suppress the intrusion of moisture into the pixel region through the cracks.

[0066] In this example, the direction of crack propagation can be changed with a probability of 90% to 94% by one bank portion 220. This reduces the probability that the crack will propagate toward the pixel region, and improves the durability of the display device 1.

[0067] FIG. 11 is a diagram showing a plurality of banks 220 provided on the display device 1. As shown in FIG.

[0068] The multiple bank portions 220 shown in FIG. 11 are provided in the outer peripheral region 101g of the substrate 101, i.e., the second region 20. The multiple bank portions 220 are arranged side by side along a direction from the inside of the substrate 101 toward the outer edge 101e. These bank portions 220 are provided between the substrate 101 and the sealing layer 108. In this example, six bank portions 220 are shown, but the number is not limited to this, and two or more bank portions 220 may be provided. For example, it is sufficient that at least two bank portions 220 are present in a linear direction from the inside of the substrate 101 toward the outer edge 101e.

[0069] In this manner, by providing a plurality of banks 220 in the direction from the inner side of the substrate 101 toward the outer edge 101e, the durability of the display device 1 can be further improved.

[0070] (summary) The display device of the present disclosure will be exemplified below.

[0071] The display device 1 of Example 1 comprises a substrate 101, an interlayer insulating layer 102 containing a resin material provided on one main surface 101c of the substrate 101 and inside an outer edge 101e of the substrate 101, an organic EL array 160 including a plurality of organic EL elements 150 provided on the interlayer insulating layer 102, a bank portion 220 provided on one main surface 101c of the substrate 101, outside the interlayer insulating layer 102 and inside the outer edge 101e of the substrate 101, and a sealing layer 108 provided continuously from on the organic EL array 160, on the interlayer insulating layer 102, and from on the bank portion 220 to the outer edge 101e of the substrate 101 or near the outer edge 101e, so as to cover the organic EL array 160, the interlayer insulating layer 102, and the bank portion 220. Bank portion 220 has a cross-sectional shape that is convex in a direction opposite to the direction toward one main surface 101c of substrate 101.

[0072] In this way, by providing the bank portion 220 on the inside of the outer edge 101e of the substrate 101, for example, when a crack occurs at the outer peripheral edge 108e of the sealing layer 108, the bank portion 220 can be used to change the direction of the crack and prevent the crack from forming in the pixel region. This makes it possible to prevent moisture from entering the pixel region through the crack, and to prevent a decrease in the display quality of the display device.

[0073] The display device 1 of Example 2 is the display device described in Example 1, and further includes an adhesive layer 109 provided on the sealing layer 108 so as to cover a portion of the sealing layer 108, and a polarizing plate 110 provided on the adhesive layer 109. An outer peripheral edge 110e of the polarizing plate 110 is located outside the interlayer insulating layer 102 and inside the outer peripheral edge 108e of the sealing layer 108, and the bank portion 220 may be located outside the outer peripheral edge 110e of the polarizing plate 110.

[0074] In this way, by positioning the outer peripheral edge 110e of the polarizing plate 110 on the inside of the outer peripheral edge 108e of the sealing layer 108, it is possible to narrow the frame of the display device 1. Even if a crack occurs at the outer peripheral edge 108e of the sealing layer 108, the bank portion 220 can be used to change the direction of the crack, thereby preventing the crack from being formed in the pixel region.

[0075] The display device 1 of Example 3 is the display device described in Example 2, and has a first region 10 including the TFT layer 101b of the substrate 101 and a second region 20 located outside the first region 10. When viewed from a direction perpendicular to the substrate 101, the interlayer insulating layer 102 is located at least in the first region 10, the organic EL array 160 is located in the first region 10, the sealing layer 108, the adhesive layer 109 and the polarizing plate 110 are located in both the first region 10 and the second region 20, and the bank portion 220 is located in the second region 20.

[0076] In this way, by providing the bank portion 220 in the second region 20, if a crack occurs, for example, at the outer peripheral edge 108e of the sealing layer 108, the bank portion 220 can be used to change the direction of the crack, thereby preventing the crack from forming in the pixel region.

[0077] The display device 1 of Example 4 is the display device described in Example 3, in which the interlayer insulating layer 102 has a lower interlayer insulating layer 102a provided on the substrate 101 and an upper interlayer insulating layer 102b provided on the side opposite to the one main surface 101c side of the lower interlayer insulating layer 102a. In the second region 20, a silicon nitride film 202 is provided on the substrate 101. The bank portion 220 is provided on the silicon nitride film 202 in the second region 20. At least a part of the bank portion 220 may be formed of the same material as the upper interlayer insulating layer 102b.

[0078] This makes it possible to simultaneously form the upper interlayer insulating layer 102b and the bank portion 220. This makes it possible to form the bank portion 220 through a simple process without the need to provide a new layer for forming the bank portion 220. This makes it possible to provide a display device 1 that can suppress the formation of cracks in the pixel region through a simple process.

[0079] The display device 1 of Example 5 is the display device according to any one of Examples 1 to 4, and the bank portions 220 may be provided in a plurality of lines in the direction from the inner side of the substrate 101 toward the outer edge 101e.

[0080] This configuration can reduce the probability that cracks will travel toward the pixel region, thereby making it possible to prevent cracks from forming in the pixel region.

[0081] (Other forms) Although the display device according to the present invention has been described above based on the embodiment, the present invention is not limited to the above embodiment. The present invention also includes modifications obtained by applying various modifications to the above embodiment that would come to mind by a person skilled in the art without departing from the spirit of the present invention, and various devices incorporating the display device according to the present invention.

[0082] For example, the organic EL element 150 may be formed by sequentially stacking a pixel electrode, a hole injection layer, an organic layer, an electron injection layer, and a counter electrode. A hole transport layer may be formed between the hole injection layer and the organic layer. An electron transport layer may be formed between the organic layer and the electron injection layer. An electron blocking layer may be formed between the hole transport layer and the organic layer to prevent electrons from reaching the hole transport layer. [Industrial Applicability]

[0083] A display device according to an embodiment of the present disclosure can be widely used in devices such as television sets, personal computers, and mobile phones, as well as various other electronic devices having a display panel. [Explanation of symbols]

[0084] 1 Display device 10 First area 20 Second area 101 Substrate 101a Base material 101b TFT layer 101c One main surface 101d Other main surface 101e Outer edge 101g outer area 102 Interlayer insulation layer 102a Lower interlayer insulating layer 102b Upper interlayer insulating layer 103 Pixel electrode 104 Bank 105 Light-emitting layer 107 Counter Electrode 108 Sealing layer 108a Lower inorganic sealing layer 108b Resin sealing layer 108c Upper inorganic sealing layer 108e Outer edge 109 Adhesive layer 110 Polarizing plate 110e Outer edge 150 Organic EL element 160 Organic EL Array 202 Silicon nitride film 203 Metal Layer 220 Bank 220a Lower bank layer 220b Upper bank layer

Claims

1. A substrate; an interlayer insulating layer including a resin material provided on one main surface side of the substrate and inside an outer edge of the substrate; an organic EL array including a plurality of organic EL (Electro Luminescence) elements provided on the interlayer insulating layer; a bank portion provided on one main surface side of the substrate, the bank portion being outside the interlayer insulating layer and inside an outer edge of the substrate; a sealing layer provided continuously from on the organic EL array, on the interlayer insulating layer, and on the bank portion to an outer edge or near the outer edge of the substrate so as to cover the organic EL array, the interlayer insulating layer, and the bank portion; Equipped with The bank portion has a cross-sectional shape that is convex in a direction opposite to a direction toward one main surface of the substrate. Display device.

2. an adhesive layer provided on the sealing layer so as to cover a portion of the sealing layer; a polarizing plate provided on the adhesive layer; Equipped with an outer circumferential edge of the polarizing plate is located outside the interlayer insulating layer and inside the outer circumferential edge of the sealing layer; The bank portion is located outside the outer circumferential edge of the polarizing plate. The display device according to claim 1 .

3. The display device has a first region including a TFT (Thin Film Transistor) layer of the substrate and a second region located outside the first region, When viewed from a direction perpendicular to the substrate, the interlayer insulating layer is located at least in the first region, the organic electroluminescence array is located in the first region, the sealing layer, the adhesive layer, and the polarizing plate are located in both the first region and the second region, The bank portion is located in the second region. The display device according to claim 2 .

4. the interlayer insulating layer includes a lower interlayer insulating layer provided on the substrate, and an upper interlayer insulating layer provided on a side opposite to the one main surface side with respect to the lower interlayer insulating layer, a silicon nitride film is provided on the substrate in the second region; the bank portion is provided on the silicon nitride film in the second region, At least a portion of the bank portion is formed of the same material as the upper interlayer insulating layer. The display device according to claim 3 .

5. The bank portion is provided in a plurality of portions in a direction from the inner side toward the outer edge of the substrate. The display device according to any one of claims 1 to 4.

Images