Self-luminous display panel and manufacturing method thereof

Abstract

The present invention provides a self-luminous display panel with excellent sealing performance and no image noise generated in the peripheral portion of the image display area. The self-luminous display panel includes an insulating resin layer arranged on a lower substrate, a plurality of self-luminous elements arranged in the image display area of ​​the insulating resin layer, a sealing portion arranged above the plurality of self-luminous elements, and a second substrate arranged on the sealing portion, wherein the insulating resin layer is divided into an inner resin layer and an outer resin layer by a circumferential groove surrounding the image display area, the sealing portion is formed so that a second sealing layer formed of a resin material is interposed between a first sealing layer and a third sealing layer formed of an inorganic material, and at the outer edge of the sealing portion, the second sealing layer is formed so that there is no second sealing layer, and the first sealing layer and the third sealing layer are directly stacked, the CF substrate is adhered to the sealing portion through a peripheral sealing layer arranged inside its peripheral edge and a bonding layer located in a range surrounded by a spacer, at least a portion of the peripheral sealing layer is located above the outer resin layer, and in a plan view, the inner end of the peripheral sealing layer is further outward than the inner peripheral edge of the circumferential groove.

Description

Technical Field

[0001] The present invention relates to a self-luminous display panel having a plurality of self-luminous elements such as organic electroluminescent (EL) elements and a method for manufacturing the same, and more particularly to a sealing technology for suppressing the penetration of moisture existing in the external environment. Background Art

[0002] In the past, an organic EL display panel including a plurality of organic EL elements is known. The organic EL element has a multilayer structure obtained by stacking thin films of various materials, and has at least a pixel electrode, a common electrode, and an organic light-emitting layer sandwiched therebetween on a TFT (Thin Film Transistor) substrate covered by a planarized insulating layer. As required, a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, etc. are provided between the pixel electrode and the organic light-emitting layer or between the common electrode and the organic light-emitting layer.

[0003] These layers may include materials whose light-emitting properties deteriorate when reacting with moisture. Therefore, in order to suppress the degradation of the display quality of the organic EL display panel over time, a sealing layer is formed on the upper layer of the common electrode to suppress the penetration of moisture existing in the external environment.

[0004] Such a sealing layer is formed using an inorganic material such as silicon nitride by a dry process such as CVD. Inorganic materials such as silicon nitride are excellent in that they do not allow water or gas to pass through, but on the other hand, they have a disadvantage that cracks are easily generated due to application of external force.

[0005] Therefore, a technical solution is proposed, in which the sealing layer has a three-layer structure, the first layer and the third layer are formed by inorganic materials, and the second layer formed by resin material is interposed between the first layer and the third layer to have a buffering effect, thereby suppressing the occurrence of cracks and improving the sealing performance (for example, patent document 1).

[0006] Generally, in an organic EL display panel, a color filter substrate (CF substrate) is disposed on a sealing layer in many cases to adjust the chromaticity of the light emitted from each light-emitting layer. Fig.12 This is a schematic cross-sectional view showing the structure of the peripheral portion of an organic EL display panel assuming this situation.

[0007] In this figure, a layer 603 in which a plurality of organic EL elements are arranged in a matrix (hereinafter referred to as an “organic EL layer”) is formed on a substrate 601 via an insulating resin layer 602 .

[0008] A sealing layer 610 is formed so as to cover the organic EL layer 603. The sealing layer 610 has a three-layer structure, and a second layer 605 formed of a resin material is interposed between a first layer 604 and a third layer 606 formed of silicon nitride.

[0009] The first layer 604 is formed using silicon nitride by a dry process such as CVD, and ink containing a resin material is applied thereon by a coating method and then cured. A silicon nitride film is further formed by CVD on the upper surface of the second layer 605 to form the third layer 606.

[0010] In general, from the viewpoint of processability and process cost, the second layer is applied by dropping ink droplets containing a resin material from a plurality of nozzles onto a target range using an inkjet method.

[0011] In this case, the viscosity of the ink is limited to a low viscosity so that the nozzle does not clog. Therefore, the ink wets and spreads in the target coating area. In the outer peripheral edge of the area, due to the surface tension of the ink, the profile of the surface of the cross section becomes a film thickness such as Fig.12 The shape is such that the thickness gradually decreases in a gently curved manner as shown (hereinafter, this portion is referred to as a "hanging portion").

[0012] In this way, if the third layer 606, the bonding layer 607, and the CF substrate 608 are arranged on the second layer 605 having the hanging portion 605a on the outer periphery, the CF substrate 608 also forms a hanging portion 608a along the curved surface of the hanging portion 605a.

[0013] Thus, if the final CF substrate 608 has a drooping portion 608a at its periphery, the drooping portion 608a has a curved surface, so the viewing angles of the central portion and the peripheral portion of the display screen of the organic EL display panel are different, resulting in uneven viewing angles. Therefore, when the display screen is viewed at an angle, the colors appear different between the central portion and the peripheral portion, which is recognized as noise and becomes a major factor that deteriorates the image quality.

[0014] Therefore, for example, in Patent Document 2, a spacer is disposed inside the outer periphery of the CF substrate 608 so as to prevent the above-mentioned hanging portion 608 a from being generated on the outer periphery of the CF substrate 608 .

[0015] Prior art literature

[0016] Patent Document 1: Japanese Patent Publication No. 2000-223264

[0017] Patent Document 2: Japanese Patent Publication No. 2009-176756

[0018] However, it is known that, according to the configuration as in Patent Document 2, although it can contribute to suppressing the occurrence of viewing angle unevenness in the outer peripheral edge portion, on the other hand, there is a possibility that the sealing property of the sealing layer will deteriorate.

[0019] Fig.13This is a schematic cross-sectional view of the outer periphery of an organic EL display panel for explaining the reason.

[0020] As shown in the figure, a peripheral sealing layer 609 is arranged on the hanging portion 605a, and the CF substrate 608 is adhered via the peripheral sealing layer 609, so that the CF substrate 608 does not generate Fig.12 The drooping portion 608a as observed in FIG. 6 is removed, and the peripheral portion of the CF substrate 608 becomes flat. As a result, the occurrence of viewing angle unevenness in the peripheral portion of the image display area is suppressed.

[0021] However, the peripheral sealing layer 609 is formed in the following manner: a peripheral sealing layer resin material obtained by mixing a solid gap forming component 6092 into a fluid resin material is applied to the inner side of the outer periphery of the CF substrate 608, and the CF substrate 608 is crimped to the sealing layer 610 on the substrate 601.

[0022] When the CF substrate 608 is pressed in a vacuum, a strong force acts, so there is a possibility that the bottom of the gap forming member 6092 contacts and breaks the third layer 606 to generate a crack c. Generally, the resin material has a weak barrier property against moisture and air, and cannot fully prevent the external moisture and air from penetrating into the interior through the crack c, so that moisture and air (especially oxygen) react with the components of the organic EL element and deteriorate them.

[0023] In addition, Fig.13 In the figure, the gap forming member 6092 is depicted as a vertically elongated ellipse, but this is because the magnification in the thickness direction (Z direction) is expressed in a manner that is much larger than the magnification in the lateral direction (X direction) in order to facilitate understanding of the stacked structure of the organic EL display panel. In fact, a gap forming member that is basically spherical is used.

[0024] In addition to organic EL display panels that use organic EL elements as self-luminous elements, the same problem as mentioned above is also common in self-luminous display panels such as inorganic EL display panels that use inorganic EL elements, quantum dot display panels that use quantum dot light-emitting elements (QLED: quantum dot-LED), etc., which have self-luminous elements that are likely to deteriorate due to reaction with external moisture or oxygen. Summary of the invention

[0025] The present invention is made in view of the above situation, and its purpose is to provide a self-luminous display panel and a manufacturing method thereof that ensures sufficient sealing in a manner that does not deteriorate the internal self-luminous elements and suppresses the occurrence of viewing angle unevenness in the peripheral portion of the image display area.

[0026] In order to achieve the above-mentioned purpose, one embodiment of the present invention relates to a self-luminous display panel, which has an image display area and a peripheral area around the image display area in a plan view, and the self-luminous display panel includes: a first substrate; an insulating resin layer, arranged above the first substrate; a plurality of self-luminous elements, arranged above the insulating resin layer and located in the image display area; a sealing portion, arranged above the plurality of self-luminous elements; and a second substrate, arranged on the sealing portion, the insulating resin layer being formed in the peripheral area and being divided into an inner insulating resin layer portion and an outer insulating resin layer portion by a circumferential groove surrounding the image display area, the sealing portion being formed in a range including the image display area and reaching at most the inner end of the outer insulating resin layer portion in a plan view. A first sealing layer formed of an inorganic material, a second sealing layer formed of a resin material, and a third sealing layer formed of an inorganic material are stacked in sequence starting from a side close to the first substrate, and the sealing portion is formed so that the second sealing layer does not exist in a range further outward than the range, the first sealing layer and the third sealing layer are directly stacked, the second substrate is adhered to the sealing portion by a peripheral sealing layer arranged on the inner side of the peripheral edge portion of the second substrate and a bonding layer arranged in a range surrounded by the peripheral sealing layer, and on a cross-section perpendicular to the main plane of the first substrate and crossing the circumferential groove, at least a portion of the peripheral sealing layer exists on the outer insulating resin layer portion, and the inner end of the peripheral sealing layer is further outward than the inner edge of the circumferential groove.

[0027] In addition, another embodiment of the present invention relates to a method for manufacturing a self-luminous display panel, which is a method for manufacturing a self-luminous display panel having an image display area and a peripheral area around the image display area in a plan view, and the method for manufacturing a self-luminous display panel includes: a first step of preparing a first substrate; a second step of forming an insulating resin layer above the first substrate; a third step of forming a plurality of self-luminous elements above the insulating resin layer and within the image display area; a fourth step of forming a sealing portion covering the top of the plurality of self-luminous elements; and a fifth step of adhering the second substrate to the sealing portion, the second step including a circumferential groove forming step, the circumferential groove forming step forming a circumferential groove in the peripheral area of ​​the insulating resin layer and dividing the insulating resin layer into an inner resin layer and an outer resin layer, and in the fourth step, in a plan view , within a range including the image display area and reaching at most the inner end of the outer resin layer, a first sealing layer formed of an inorganic material, a second sealing layer formed of a resin material, and a third sealing layer formed of an inorganic material are stacked in sequence starting from the side close to the first substrate, and in a range further outward than the range, the second sealing layer does not exist, and the first sealing layer and the third sealing layer are directly stacked. In the fifth step, the second substrate is adhered to the sealing portion by a peripheral sealing layer arranged on the inner side of the peripheral edge portion of the second substrate and a bonding layer located in a range surrounded by the peripheral sealing layer. On a cross section perpendicular to the main plane of the first substrate and crossing the circumferential groove, at least a portion of the peripheral sealing layer exists on the outer resin layer, and the inner end of the peripheral sealing layer is further outward than the inner edge of the circumferential groove.

[0028] The self-luminous display panel and the method for manufacturing the same according to the present invention can ensure sealing and prevent degradation of the self-luminous element, and can suppress the deterioration of image quality caused by the occurrence of viewing angle unevenness in the periphery of the image display area. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a plan layout diagram of an organic EL display panel according to a first embodiment which is one mode of the present invention.

[0030] Figure 2 Yes means Figure 1 A schematic cross-sectional view of the stacked structure of the organic EL display panel at line BB in region A.

[0031] Figure 3 It is a flowchart showing the manufacturing process of the organic EL display panel of the above-mentioned embodiment.

[0032] Figure 4(a) to (c) are schematic cross-sectional views for explaining part of the manufacturing process of the above-mentioned organic EL display panel.

[0033] Figure 5 (a) to (g) are schematic cross-sectional views for explaining the manufacturing process of the CF substrate of the above-mentioned organic EL display panel.

[0034] Figure 6 (a) to (d) are diagrams for explaining a process for adhering a CF substrate to an intermediate product of an organic EL display panel.

[0035] Figure 7 (a) and (b) are used to explain the following Figure 6 Figure 2 is a diagram of the manufacturing process of an organic EL display panel.

[0036] Figure 8 This is a schematic diagram showing the configuration of an organic EL display device in which the organic EL display panel according to the first embodiment is incorporated.

[0037] Fig. 9 This is a schematic cross-sectional view showing a second embodiment of the sealing structure of the organic EL display panel according to one aspect of the present invention.

[0038] Fig.10 This is a schematic cross-sectional view showing a first modified example of the sealing structure of the organic EL display panel according to one embodiment of the present invention.

[0039] Fig.11 This is a schematic cross-sectional view showing a second modified example of the sealing structure of the organic EL display panel according to one embodiment of the present invention.

[0040] Fig.12 This is a schematic cross-sectional view showing a stacked structure of a peripheral portion of an organic EL display panel, which is a premise for explaining the problem of the present invention.

[0041] Fig.13 This is a schematic cross-sectional view showing the stacked structure of the peripheral portion of a conventional organic EL display panel.

[0042] Description of Reference Numerals

[0043] 10 Display area

[0044] 20 Surrounding Areas

[0045] 100 Organic EL display panel

[0046] 101 substrate

[0047] 101a Substrate

[0048] 101b TFT layer

[0049] 102 interlayer insulation layer (insulating resin layer)

[0050] 1021 Outer insulation layer

[0051] 1022 Circumferential groove

[0052] 1023 Inner insulation layer

[0053] 103 pixel electrodes

[0054] 104 partition wall layer

[0055] 105 Luminous Layer

[0056] 106 Electron transport layer

[0057] 107 Counter electrode

[0058] 108 Sealing layer

[0059] 1081 First Sealing Layer

[0060] 1082 Second sealing layer

[0061] 1083 Third Sealing Layer

[0062] 109 Bonding layer

[0063] 110 Peripheral sealing layer

[0064] 111 Color filter substrate

[0065] 113 Passivation film DETAILED DESCRIPTION

[0066] <Method of Invention>

[0067] An organic EL display panel according to one embodiment of the present invention has an image display area and a peripheral area around it in a plan view, and the organic EL display panel includes: a first substrate; an insulating resin layer, arranged above the first substrate; a plurality of self-luminous elements, arranged above the insulating resin layer and located in the image display area; a sealing portion, arranged above the plurality of self-luminous elements; and a second substrate, arranged on the sealing portion, the insulating resin layer being formed in the peripheral area and being divided into an inner insulating resin layer portion and an outer insulating resin layer portion by a circumferential groove surrounding the image display area, the sealing portion being formed so as to extend from near the first insulating resin layer in a range including the image display area and reaching at most the inner end of the outer insulating resin layer portion in a plan view. A first sealing layer formed of an inorganic material, a second sealing layer formed of a resin material, and a third sealing layer formed of an inorganic material are sequentially stacked on one side of the substrate, and the sealing portion is formed so that the second sealing layer does not exist in a range further outward than the range, the first sealing layer and the third sealing layer are directly stacked, the second substrate is adhered to the sealing portion by a peripheral sealing layer arranged on the inner side of the peripheral edge portion of the second substrate and a bonding layer arranged in a range surrounded by the peripheral sealing layer, and on a cross section perpendicular to the main plane of the first substrate and crossing the circumferential groove, at least a portion of the peripheral sealing layer exists on the outer insulating resin layer portion, and the inner end of the peripheral sealing layer is further outward than the inner edge of the circumferential groove.

[0068] According to this aspect, it is possible to ensure sealing performance and prevent the self-luminous element from being deteriorated, and to suppress the deterioration of image quality due to the occurrence of viewing angle unevenness in the peripheral portion of the image display region.

[0069] In another aspect of the present invention, the thickness of the second sealing layer is thinner than the thickness of the outer insulating resin layer portion at the inner end portion of the peripheral sealing layer.

[0070] Thus, at least compared with the conventional configuration, since the pressing force applied to the third sealing layer of the sealing portion is relieved by the inner end of the peripheral sealing layer, the possibility of the third sealing layer being damaged and the sealing performance being deteriorated can be reduced. In addition, here, "the thickness of the second sealing layer is thinner than the thickness of the outer insulating resin layer at the position of the inner end of the peripheral sealing layer" also includes the case where the thickness of the second sealing layer at the position of the inner end of the peripheral sealing layer is "0", that is, the case where the second sealing layer does not extend to the position of the inner edge of the peripheral sealing layer.

[0071] In another aspect of the present invention, a portion of the sealing portion where the first sealing layer and the third sealing layer are directly laminated extends to cover an outer peripheral end surface of the outer insulating resin layer portion.

[0072] According to this aspect, it is possible to prevent moisture and the like from penetrating from the outer insulating resin layer portion, and to further improve the sealing performance.

[0073] In another aspect of the present invention, in a plan view, an outer end portion of the peripheral seal layer is located outside the outer peripheral edge of the outer insulating resin layer portion.

[0074] Even in this embodiment, it is possible to prevent moisture and the like from penetrating from the outer insulating resin layer portion, and the sealing performance can be further improved.

[0075] In another aspect of the present invention, the second substrate is a color filter substrate having at least red, green, and blue color filters.

[0076] According to this embodiment, the second substrate can not only improve the sealing performance but also has the function of improving the purity of the light emitting color of each color of the light emitting element.

[0077] Moreover, in another aspect of the present invention, the second sealing layer is formed of a coating film.

[0078] In this manner, the second sealing layer can be easily formed by a coating method.

[0079] In another embodiment of the present invention, the peripheral sealing layer is formed by dispersing spherical gap-forming members in an ultraviolet curable resin material.

[0080] According to this aspect, the gap forming member can easily limit the thickness of the peripheral sealing layer.

[0081] In addition, another embodiment of the present invention is a method for manufacturing a self-luminous display panel, which is a method for manufacturing a self-luminous display panel having an image display area and a peripheral area around the image display area in a plan view, and the method for manufacturing a self-luminous display panel includes: a first step of preparing a first substrate; a second step of forming an insulating resin layer above the first substrate; a third step of forming a plurality of self-luminous elements above the insulating resin layer and within the image display area; a fourth step of forming a sealing portion covering the top of the plurality of self-luminous elements; and a fifth step of adhering the second substrate to the sealing portion, the second step including a circumferential groove forming step, the circumferential groove forming step forming a circumferential groove in the peripheral area of ​​the insulating resin layer and dividing the insulating resin layer into an inner resin layer and an outer resin layer, and the fourth step, in a plan view, In a range including the image display area and reaching at most the inner end of the outer resin layer, a first sealing layer formed of an inorganic material, a second sealing layer formed of a resin material, and a third sealing layer formed of an inorganic material are stacked in sequence starting from the side close to the first substrate, and in a range further outward than the range, the second sealing layer does not exist, and the first sealing layer and the third sealing layer are directly stacked. In the fifth step, the second substrate is adhered to the sealing portion through a peripheral sealing layer arranged on the inner side of its peripheral edge portion and a bonding layer located in a range surrounded by the peripheral sealing layer. In a cross section perpendicular to the main plane of the first substrate and crossing the circumferential groove, at least a portion of the peripheral sealing layer exists on the outer resin layer, and the inner end of the peripheral sealing layer is further outward than the inner edge of the circumferential groove.

[0082] According to this aspect, it is possible to ensure sealing performance and prevent the self-luminous element from being deteriorated, and to suppress the deterioration of image quality due to the occurrence of viewing angle unevenness in the peripheral portion of the image display region.

[0083] In addition, in the above-mentioned inventions, "up" does not refer to the absolute upward direction (vertically above) in spatial perception, but is determined by the relative positional relationship based on the stacking order of the stacking structure of the self-luminous display panel. Specifically, in the self-luminous display panel, the direction perpendicular to the main plane of the substrate and from the substrate toward the side of the stack is taken as the upward direction. In addition, for example, the expression "on the substrate" does not only refer to the area in direct contact with the substrate, but also includes the area above the substrate separated by the stack. In addition, for example, the expression "above the substrate" does not only refer to the area above the substrate separated by a gap, but also includes the area on the substrate.

[0084] <Implementation Method>

[0085] Hereinafter, a self-luminous display panel according to one embodiment of the present invention will be described with reference to the accompanying drawings, taking a top-emitting organic EL display panel as an example. In addition, the accompanying drawings include schematic diagrams, and the scale of each component, the ratio of the vertical and horizontal dimensions, etc. may be different from the actual ones.

[0086] <First embodiment>

[0087] 1. Configuration of the Organic EL Display Panel 100

[0088] 1.1 Overview of the structure

[0089] Figure 1 1 is a plan layout diagram of the organic EL display panel 100 according to the first embodiment.

[0090] As shown in the figure, the organic EL display panel 100 has an image display region 10 and a peripheral region 20 surrounding the image display region 10 in a plan view.

[0091] A plurality of pixels are arranged in a matrix in the image display area 10. Each pixel includes a plurality of sub-pixels of different colors. In the present embodiment, a pixel includes a red sub-pixel, a green sub-pixel, and a blue sub-pixel. One sub-pixel is formed by one organic EL element.

[0092] In addition, a plurality of terminals (not shown) for electrical connection with an external drive circuit are arranged in the peripheral region 20 .

[0093] 1.2 Layered Structure of Organic EL Display Panel 100

[0094] Figure 2 FIG. 1 is a partial cross-sectional view showing a laminated structure of the outer peripheral edge portion of the organic EL display panel 100, and illustrates Figure 1 The cross section at line BB in area A.

[0095] As shown in the figure, the organic EL display panel 100 includes a lower substrate 101 (first substrate), an interlayer insulating layer (insulating resin layer) 102, a pixel electrode 103, a partition wall layer 104, a light-emitting layer 105, an electron transport layer 106, an opposing electrode 107, a sealing layer 108, a color filter substrate 111 (second substrate) as an upper substrate, a wiring layer 112, and a passivation film 113. Among them, the pixel electrode 103, the partition wall layer 104, and the light-emitting layer 105 are mainly formed for each sub-pixel.

[0096] The pixel electrode 103 , the partition wall layer 104 , the light-emitting layer 105 , the electron transport layer 106 , and the counter electrode 107 are collectively referred to as an organic EL layer 120 .

[0097] (1) Lower substrate (first substrate)

[0098] The lower substrate 101 includes a base material 101a as an insulating material and a TFT (Thin Film Transistor) layer 101b. On the TFT layer 101b, a well-known driving circuit formed of TFTs is formed for each sub-pixel.

[0099] The substrate 101a usually uses a glass plate. When flexibility is given priority, it is preferred to use a sheet formed of an insulating resin material. As the resin material in this case, any resin of a thermoplastic resin or a thermosetting resin can be used. For example, polyethylene, polypropylene, polyamide, polyimide (PI), polycarbonate, acrylic resin, polyethylene terephthalate (PET), polybutylene terephthalate, polyacetal, other fluorine resins, styrene resins, polyolefin resins, polyvinyl chloride resins, polyurethane resins, fluororubber resins, chlorinated polyethylene resins and other thermoplastic elastomers, epoxy resins, unsaturated polyesters, silicone resins, polyurethanes, etc., or copolymers, mixtures, polymer alloys, etc. based on them can be used, and a laminate obtained by stacking one or more of them can be used.

[0100] (2) Wiring layer

[0101] The wiring layer 112 includes a plurality of wirings extending from the TFT layer 101b. The wirings are formed at intervals from each other and are formed of a conductive material such as a metal such as chromium (Cr), molybdenum (Mo), aluminum (Al), titanium (Ti), copper (Cu), or an alloy (such as MoW, MoCr, NiCr).

[0102] (3) Passivation film

[0103] The passivation film 113 is an insulating protective film covering the TFT layer 101b and the wiring layer 112, and is formed of silicon nitride (SiN), silicon oxide (SiO), silicon oxynitride (SiON), etc. In the peripheral area 20, the connection terminal (not shown) led out from the wiring layer 112 is exposed from the passivation film 113 and connected to the drive circuit described later.

[0104] (4) Interlayer insulation layer

[0105] An interlayer insulating layer (insulating resin layer) 102 is formed on the lower substrate 101. The interlayer insulating layer 102 is formed of an insulating resin material, has a thickness of, for example, 3 μm, and flattens the step on the upper surface of the passivation film 113 formed on the TFT layer 101 b. Examples of the resin material include acrylic resins, polyimide resins, siloxane resins, and phenolic resins.

[0106] In addition, in the peripheral region 20 of the interlayer insulating layer 102, a groove (hereinafter referred to as a "circumferential groove") 1022 is formed along the outer peripheral edge of the interlayer insulating layer 102 (see Figure 1 ), whereby the interlayer insulating layer 102 is completely separated into the inner insulating layer 1023 and the outer insulating layer 1021, and the passivation film 113 is exposed at the bottom of the circumferential groove 1022.

[0107] As described above, the interlayer insulating layer 102 is formed of an insulating material such as a polyimide resin or an acrylic resin, and has the property of easily absorbing moisture. However, by providing the circumferential groove 1022, even if moisture enters the outer insulating layer 1021 outside the circumferential groove 1022 from the outer edge direction of the substrate, the penetration of moisture into the image display area 10 can be suppressed.

[0108] In addition, when the second sealing layer 1082 of the sealing layer 108 is formed by a coating method, the resin serving as the material thereof has fluidity during coating, and therefore there is a possibility that the coating may extend to the position of the connection terminal (not shown) for external connection. However, by providing such a circumferential groove 1022, the groove acts as a "moat" and can prevent unnecessary wetting and spreading of the resin material at the edge on the image display area 10 side when the second sealing layer 1082 is formed.

[0109] Furthermore, even if the resin material flows into the circumferential groove 1022 , the outer insulating layer 1021 acts as a so-called “dam”, thereby preventing the resin material applied to form the second sealing layer 1082 from wetting and spreading at the inner end of the outer insulating layer 1021 .

[0110] (5) Pixel electrode

[0111] The pixel electrode 103 includes a metal layer formed of a light-reflective metal material, and is formed on the interlayer insulating layer 102. The pixel electrode 103 is provided for each sub-pixel, and is electrically connected to the TFT layer 101b through a contact hole.

[0112] In this embodiment, the pixel electrode 103 functions as an anode.

[0113] Specific examples of metal materials with light reflectivity include Ag (silver), Al (aluminum), aluminum alloys, Mo (molybdenum), APC (an alloy of silver, palladium and copper), ARA (an alloy of silver, rubidium and gold), MoCr (an alloy of molybdenum and chromium), MoW (an alloy of molybdenum and tungsten), NiCr (an alloy of nickel and chromium), etc.

[0114] The pixel electrode 103 may be formed of a metal layer alone, or may have a stacked structure in which a layer formed of a metal oxide such as ITO (indium tin oxide) or IZO (indium zinc oxide) is stacked on a metal layer.

[0115] (6) Partition wall layer

[0116] The partition wall layer 104 is formed in a state where a part of the upper surface of the pixel electrode 103 is exposed and the surrounding area of ​​the exposed part is covered.

[0117] On the upper surface of the pixel electrode 103 , a region not covered by the partition wall layer 104 (hereinafter referred to as an “opening”) corresponds to a sub-pixel.

[0118] The partition wall layer 104 is formed of, for example, an insulating organic material (e.g., acrylic resin, polyimide resin, novolac resin, phenolic resin, etc.) When the light-emitting layer 105 is formed by a coating method, the partition wall layer 104 functions as a structure for preventing the coated ink from overflowing, and when the light-emitting layer 105 is formed by a vapor deposition method, the partition wall layer 104 functions as a structure for placing a vapor deposition mask.

[0119] (7) Luminescent layer

[0120] The light emitting layer 105 is formed in the opening of the partition wall layer 104 and has a function of emitting light of each color of R, G, and B through recombination of holes and electrons.

[0121] As the material of the light-emitting layer 105, a well-known material can be used. Specifically, for example, preferably, a chelated oxine compound (オキシノイド compound), a perylene compound, a coumarin compound, an azacoumarin compound, an oxazole compound, an oxadiazole compound, a perinone compound (ペリノン compound), a pyrrolopyrrole compound, a naphthalene compound, an anthracene compound, a fluorene compound, a fluoranthene compound, a tetracene compound, a pyrene compound, a coronene compound, a quinolone compound and an azaquinolone compound, a pyrazoline derivative and a pyrazolone derivative, a rhodamine compound, Fluorescent substances are formed by compounds, phenanthrene compounds, cyclopentadiene compounds, distilbene compounds, diphenylbenzoquinone compounds, styrene compounds, butadiene compounds, dicyanomethylenepyran compounds, dicyanomethylenethiopyran compounds, fluorescein compounds, pyrylium compounds, thiopyrylium compounds, selenopyrylium compounds, telluropyrylium compounds, aromatic aldazine compounds, oligophenylene compounds, thioxanthene compounds, cyanine compounds, acridine compounds, metal complexes of 8-hydroxyquinoline compounds, metal complexes of 2-bipyridine compounds, complexes of Schiff bases and Group III metals, 8-hydroxyquinoline metal complexes, rare earth complexes, etc.

[0122] (8) Electron transport layer

[0123] The electron transport layer 106 has the function of transporting electrons from the counter electrode 107 to the light-emitting layer 105. The electron transport layer 106 is formed, for example, of an organic material with high electron transport properties, specifically, of a π-electron low-molecular organic material such as an oxadiazole derivative (OXD), a triazole derivative (TAZ), or a phenanthroline derivative (BCP, Bphen). The electron transport layer 106 may also be doped with a doping metal selected from an alkali metal or an alkaline earth metal. Alternatively, for example, the electron transport layer 106 may also be formed of a single substance or a fluoride of a metal selected from an alkali metal or an alkaline earth metal.

[0124] (9) Opposing Electrode

[0125] The counter electrode 107 is made of a light-transmitting conductive material and is formed on the electron transport layer 106. The counter electrode 107 functions as a cathode.

[0126] As a material of the counter electrode 107, for example, ITO, IZO, etc. can be used. Alternatively, as a material of the counter electrode 107, a thin film of a metal such as silver, a silver alloy, aluminum, or an aluminum alloy can be used.

[0127] (10) Sealing layer

[0128] The sealing layer 108 has a function of preventing organic layers such as the light-emitting layer 105 and the electron transport layer 106 from being exposed to moisture or air.

[0129] The sealing layer 108 is formed of three layers, namely, a first sealing layer 1081 , a second sealing layer 1082 , and a third sealing layer 1083 , each of which has light transparency.

[0130] The first sealing layer 1081 is a thin film of silicon nitride (SiN), and covers the upper surface of the counter electrode 107 .

[0131] The second sealing layer 1082 is formed of a resin, and covers the upper surface of the first sealing layer 1081 except for the peripheral portion thereof. As the resin material forming the second sealing layer 1082, for example, a transparent epoxy-based resin or an acrylic-based resin is used.

[0132] The third sealing layer 1083 is also a silicon nitride thin film similar to the first sealing layer 1081 , and covers the upper surface of the second sealing layer 1082 .

[0133] In a plan view, the first sealing layer 1081 extends to a position covering the outer end surface of the outer insulating layer 1021 formed of a resin material in the peripheral region 20 and covers the entire surface of the outer insulating layer 1021. Therefore, it is possible to prevent moisture and the like from entering the inner portion through the outer insulating layer 1021.

[0134] The second sealing layer 1082 is formed on the first sealing layer 1081 using a resin material by a coating method such as an inkjet method. The thickness of the second sealing layer 1082 is formed to be substantially uniform in the image display area 10, for example, 3 μm. In addition, the outer edge of the second sealing layer 1082 only needs to be closer to the image display area 10 than the inner edge of the outer insulating layer 1021 (the inner edge of the flat portion: position P5). Figure 2 1 shows an embodiment in which the outer edge of the second sealing layer 1082 is closer to the image display area 10 than the inner peripheral edge (position P4) of the circumferential groove 1022. In this embodiment, the thickness of the second sealing layer 1082 at position P1 of the inner end 110a of the peripheral sealing layer 110 is "0".

[0135] At the position P1 in the circumferential groove 1022 , the gap forming member 1101 does not abut against the third sealing layer 1083 , and the second sealing layer 1082 is not arranged below the third sealing layer 1083 , so the sealing performance of the sealing layer 108 is not impaired.

[0136] In addition, the third sealing layer 1083 extends to the outside of the outer insulating layer 1021 , and the outer edge of the first sealing layer 1081 is directly and closely attached to the outer edge of the third sealing layer 1083 without the second sealing layer 1082 interposed therebetween.

[0137] This can prevent moisture from directly penetrating into the interlayer insulating layer 102 and the second sealing layer 1082 from the outside of the substrate, and can further improve the sealing performance of the sealing layer 108 .

[0138] (11) Color filter (CF) substrate (second substrate)

[0139] The color filter substrate 111 is formed by forming a color filter layer 1112 on a main plane on one side of the plate substrate 1111, and the color filter layer 1112 side faces downward, and the color filter substrate 111 is adhered to the sealing layer 108 via the bonding layer 109 and the peripheral sealing layer 110. The bonding layer 109 and the peripheral sealing layer 110 are collectively referred to as an adhesive layer.

[0140] A light-transmitting material such as cover glass or a transparent resin film is used as the plate substrate 1111. The plate substrate 1111 can improve the rigidity of the organic EL display panel 100 and prevent the entry of moisture and air.

[0141] On the color filter layer 1112, red (R), green (G), and blue (B) color filters 1113R, 1113G, and 1113B are formed at positions corresponding to the respective sub-pixels, and transmit visible light having wavelengths corresponding to R, G, and B. The color filter layer 1112 has the function of transmitting light emitted from the organic EL elements of each color and correcting its chromaticity.

[0142] (12) Bonding layer and peripheral sealing layer

[0143] The bonding layer 109 is formed by curing a transparent ultraviolet curable resin, and functions as an adhesive when the color filter substrate 111 is attached to the upper surface of the sealing layer 108 via the adhesive layer.

[0144] The peripheral sealing layer 110 is formed by mixing a spherical gap forming member 1101 into an ultraviolet curable resin and is disposed on the peripheral edge of the color filter substrate 111 (see FIG. Figure 1 ), whereby the color filter substrate 111 is maintained in a state where its entire surface is parallel to the lower substrate 101 (see Figure 2 ).

[0145] The bonding layer 109 can further prevent external moisture, air, etc. from entering the organic EL display panel 100 .

[0146] If you watch Figure 2 It can be understood that in the organic EL display panel 100 of this embodiment, since the end of the color filter substrate 111 is kept horizontal by the peripheral sealing layer 110, viewing angle unevenness does not occur and image noise does not occur in the peripheral portion of the image display area.

[0147] Moreover, in Figure 2 In the configuration of the peripheral sealing layer 110, the position P1 of the inner end 110a is located within the width of the circumferential groove 1022, which is not as large as in the conventional configuration. Fig.13 As shown in the figure, the gap forming member 1101 of the peripheral sealing layer 110 abuts against the third sealing layer 1083 and strongly presses the third sealing layer 1083 downward. Therefore, when the color filter substrate 111 is pressed, the gap forming member 1101 will not damage the third sealing layer 1083 of the sealing layer 108, and excellent sealing can be maintained.

[0148] in addition, Figure 2 The dimensions described are merely examples for reference, and in order to make the stacked structure easier to understand, the lengths and widths of the various parts are not necessarily proportional to the dimensions described.

[0149] 2. Method for manufacturing organic EL display panel

[0150] A method for manufacturing the organic EL display panel 100 will be described with reference to the drawings.

[0151] Figure 3 1 is a flowchart showing the manufacturing process of the organic EL display panel 100 .

[0152] (1) Formation of Lower Substrate 101

[0153] First, a TFT layer 101b and a wiring layer 112 are formed on a base material 101a, thereby forming a lower substrate 101 ( Figure 3 Step S1) The TFT layer 101b and the wiring layer 112 can be formed by a well-known TFT manufacturing method.

[0154] In addition, a passivation film 113 is formed on the TFT layer 101b. The passivation film 113 is formed of silicon nitride (SiN), silicon oxide (SiO), silicon oxynitride (SiON), etc., and prevents the entry of impurities contained in the interlayer insulating layer 102 and the partition wall layer 104, thereby protecting the TFT layer 101b and the wiring layer 112. The passivation film 113 is formed by, for example, a plasma CVD method or a sputtering method.

[0155] The interlayer insulating layer 102 is formed on the passivation film 113. The interlayer insulating layer 102 can be formed by, for example, a plasma CVD method, a sputtering method, or the like.

[0156] Next, a contact hole is formed by dry etching a portion of the interlayer insulating layer 102 on the source electrode of the TFT layer 101b. The contact hole is formed so that, for example, the surface of the source electrode of the TFT is exposed at the bottom thereof.

[0157] In addition, a circumferential groove 1022 is formed in the peripheral portion of the interlayer insulating layer 102 by dry etching, and the interlayer insulating layer 102 is separated into an outer insulating layer 1021 and an inner insulating layer 1023. There is no interlayer insulating layer 102 at the bottom of the circumferential groove 1022, and dry etching is performed until the upper surface of the passivation film 113 is exposed.

[0158] Next, the connection electrode 103a is formed along the inner wall of the contact hole. A portion of the upper portion of the connection electrode is disposed on the interlayer insulating layer 102 and the passivation film 113. The connection electrode can be formed by forming a metal film by sputtering and then patterning it by photolithography and wet etching.

[0159] Alternatively, the interlayer insulating layer 102 may be formed using a well-known photoresist method.

[0160] (2) Formation of pixel electrode 103

[0161] Next, a pixel electrode material layer is formed on the interlayer insulating layer 102. The pixel electrode material layer can be formed by, for example, a vacuum deposition method or a sputtering method.

[0162] Next, the pixel electrode material layer is patterned by etching to form a plurality of pixel electrodes 103 ( Figure 3 Step S2).

[0163] (3) Formation of partition wall layer (bank) 104

[0164] Next, a partition wall layer resin, which is a material of the partition wall layer 104 , is applied onto the pixel electrode 103 and the interlayer insulating layer 102 to form a partition wall material layer.

[0165] The partition wall material layer is formed by uniformly applying a solution onto the pixel electrode 103 and the interlayer insulating layer 102 by a spin coating method or the like. The solution is obtained by dissolving a phenolic resin as a resin for the partition wall layer in a solvent (e.g., a mixed solvent of ethyl lactate and GBL). Then, the partition wall material layer is subjected to pattern exposure and development to form a partition wall layer (strip stack) 104 ( Figure 3 The partition wall layer 104 is fired (step S4). Thus, an opening portion that becomes a formation region of the light emitting layer 105 is defined. The partition wall layer 104 is fired at a temperature of 150° C. to 210° C. for 60 minutes, for example.

[0166] In addition, in the process of forming the partition wall layer 104, the surface of the partition wall layer 104 may be further treated with a predetermined alkaline solution, water, an organic solvent, or subjected to plasma treatment. This is to impart hydrophobicity to the surface of the partition wall layer 104 with respect to the ink (solution) applied to the opening so that color mixing does not occur when the ink is applied.

[0167] (4) Formation of the Light Emitting Layer 105

[0168] Next, ink containing the constituent material of the light-emitting layer 105 is applied to the openings defined by the partition wall layer 104 using an inkjet device and dried (fired) to form the light-emitting layer 105 ( Figure 3 Step S5). Other coating methods include a dispense method, a screen printing method, and the like.

[0169] (5) Formation of the Electron Transport Layer 106

[0170] Next, the electron transport layer 106 is formed on the light emitting layer 105 and the partition wall layer 104 ( Figure 3 The electron transport layer 106 is formed by forming a film on each sub-pixel by, for example, vapor deposition.

[0171] (6) Formation of Counter Electrode 107

[0172] Next, a counter electrode 107 is formed on the electron transport layer 106 ( Figure 3 The counter electrode 107 is formed by forming a film of ITO, IZO, silver, aluminum, or the like by sputtering or vacuum deposition.

[0173] (7) Formation of Sealing Layer 108

[0174] A sealing layer 108 is formed on the counter electrode 107 ( Figure 3 Step S8).

[0175] First, SiN is formed into a film by, for example, a plasma CVD method, thereby forming a first sealing layer 1081 ( Figure 4 As the raw material gas, for example, silane (SiH 4 ) and ammonia (NH 3 ) are used, and nitrogen (N 2 ) may also be used.

[0176] The outer edge of the first sealing layer 1081 extends to the outer side of the outer insulating layer 1021 on the peripheral region 20. At this time, the first sealing layer 1081 directly contacts the passivation film 113 at the bottom of the circumferential groove 1022 and the outer side of the outer insulating layer 1021.

[0177] Next, a resin material is ejected from the nozzle 310 of the head 300 of the inkjet device onto the first sealing layer 1081 to form the second sealing layer 1082 ( Figure 4 (b)) and cure it. For example, if these resin materials are thermosetting, they are heated, and if these resin materials are ultraviolet curable, they are irradiated with ultraviolet rays, thereby enabling the resin materials to be cured.

[0178] As a method for applying the resin material, in addition to the above-mentioned inkjet method, a screen printing method, a drop coating method, a spin coating method, etc. can also be used.

[0179] The third sealing layer 1083 is formed on the second sealing layer 1082 under the same film forming conditions as the first sealing layer 1081. Figure 4 (c)).

[0180] As described above, by utilizing the cutting effect of the circumferential groove 1022, the outer edge of the second sealing layer 1082 is closer to the inner insulating layer 1023 side (light emitting region side) than the inner circumferential edge of the circumferential groove 1022, and the first sealing layer 1081 and the third sealing layer 1083 extend to the outside of the outer insulating layer 1021 in a plan view, so the first sealing layer 1081 and the third sealing layer 1083 are directly stacked at their outer edges without intervening the second sealing layer 1082. Since there is no possibility that the resin of the second sealing layer 1082 is exposed to the outside, it is difficult for moisture in the atmosphere to penetrate into the second sealing layer 1082.

[0181] (8) Formation and Adhesion of Color Filter Substrate 111

[0182] Next, a color filter substrate 111 is formed and attached to the sealing layer 108 ( Figure 3 Step S9).

[0183] (8-1) Formation of Color Filter Substrate 111

[0184] First, a transparent plate substrate 1111 is prepared, and a light shielding layer 1114 having a UV-curable resin (e.g., UV-curable acrylic resin) material as a main component and black pigment added thereto is applied to the surface of one side of the transparent plate substrate 1111, thereby forming a light shielding material layer 1114a ( Figure 5 (a)).

[0185] A pattern mask PM1 having a predetermined opening is overlapped on the upper surface of the light shielding material layer 1114a after coating, and ultraviolet light is irradiated from above ( Figure 5 (b)).

[0186] Thereafter, the pattern mask PM1 and the uncured light shielding material layer 1114a are removed and developed, and then cured to complete the light shielding layer 1114 ( Figure 5 (c)).

[0187] Next, a paste 1113G of a color filter 1113 (eg, G) having an ultraviolet curable resin component as a main component is applied to the surface of the plate substrate 1111 on which the light shielding layer 1114 is formed ( Figure 5 (d)), place the prescribed pattern mask PM2 and irradiate with ultraviolet light ( Figure 5 (e)).

[0188] After curing, if the pattern mask PM2 and the uncured paste are removed and developed, the color filter 1113G ( Figure 5 (f)).

[0189] This process is repeated for the red and blue color filter materials. Figure 5 The steps (d), (e), and (f) are performed to form the color filters 1113R and 1113B ( Figure 5 (g)).

[0190] In addition, a commercially available color filter product may be used instead of the paste of each color. The color filter substrate 111 is formed in the above manner.

[0191] The color filter substrate 111 may be formed by Figure 3 The manufacturing processes can be performed in parallel, or can be performed first.

[0192] (8-2) Step of attaching the color filter substrate 111

[0193] Next, the color filter substrate 111 is attached to an intermediate product of an organic EL display panel (hereinafter referred to as “rear panel 1200 ”) formed of the layers from the lower substrate 101 to the sealing layer 108 .

[0194] Figure 6 (a) to (d) are process drawings schematically showing the steps.

[0195] First, the surface of the plate base material 1111 (color filter substrate 111) on which the color filter layer 1112 is formed faces upward, and the ink that will become the material of the peripheral sealing layer 110 is applied from the nozzle 301 of the ink dropper along the outer periphery of the color filter substrate 111 to the inner part of the outer periphery in a frame shape to form the peripheral sealing layer precursor 1100 ( Figure 6 (a)).

[0196] The ink used at this time is obtained by mixing a large number of spherical solid gap-forming components 1101 with a diameter of 15 μm into a resin material 1102 whose main component is an ultraviolet-curing resin such as acrylic resin, silicone resin, epoxy resin, etc., and the viscosity is preferably slightly higher than the resin material used to form the bonding layer 109 described next.

[0197] This is because the ink used to form the peripheral sealing layer 110 also has a so-called “dam” function to prevent the compressed bonding layer resin material from leaking to the outside when the color filter substrate 111 is pressure-bonded to the back panel 1200 .

[0198] The diameter of the gap forming member 1101 does not need to be strictly 15 μm, and may include manufacturing tolerances. This is because even if there is a slight error, it is at least possible to improve the viewing angle unevenness compared to the past.

[0199] Next, ink containing a resin material to be the bonding layer 109 is sprayed from the nozzle 302 at appropriate intervals into a plurality of ink blocks 1090 ( Figure 6 (b)). The ink used for the bonding layer 109 also contains ultraviolet curing resin as a main component.

[0200] Then, the ultraviolet light is irradiated from the upper side of the plate substrate 1111 to the peripheral sealing layer precursor 1100 and the ink block 1090, so that the peripheral sealing layer precursor 1100 and the ink block 1090 are semi-cured ( Figure 6 (c)).

[0201] Then, the back panel 1200 and the color filter substrate 111 are bonded together while maintaining their relative positional relationship, and are carried into the vacuum chamber 400 . The air in the vacuum chamber 400 is exhausted and vacuum-bonded, thereby producing a semi-finished product 1000 of the organic EL display panel 100 .

[0202] At this time, the ink block 1090 is flattened to form a bonding layer that is in close contact with the upper surface of the sealing layer 108. Although the peripheral sealing layer precursor 1100 is also flattened, it is not flattened below the diameter of the gap forming member 1101 because it contains the gap forming member 1101 inside, and functions as a spacer.

[0203] In addition, as described above, the peripheral sealing layer precursor 1100 acts as a dam, thereby preventing the internal ink block 1090 from leaking to the outside. Therefore, by appropriately adjusting the amount of ink block 1090 dripped, the color filter substrate 111 can be bonded to the sealing layer 108 in a tightly adhered state while maintaining the flatness of the color filter substrate 111.

[0204] Thereafter, the semi-finished product 1000 is taken out from the vacuum chamber 400 and turned upside down ( Figure 7 (a)), placed in a heating chamber 500, and heated at a predetermined temperature to be fired ( Figure 7 (b)), thereby completing the organic EL display panel 100.

[0205] The execution order of the above steps is an illustrative order for specifically explaining the present invention, and may be an order other than the above. In addition, a part of the above steps may be executed simultaneously (in parallel) with other steps.

[0206] 3. Organic EL display device

[0207] Figure 8The organic EL display device 1 is a block diagram showing the overall structure of an organic EL display device 1 equipped with the organic EL display panel 100 as a display unit. The organic EL display device 1 is a display device used in, for example, televisions, personal computers, portable terminals, business displays (electronic signs, large screens for commercial facilities), and the like.

[0208] The organic EL display device 1 includes an organic EL display panel 100 and a drive control unit 200 electrically connected thereto.

[0209] The drive control unit 200 includes: drive circuits 210 to 240 connected to the organic EL display panel 100; and a control circuit 250 connected to an external device such as a computer or a receiving device such as an antenna. The drive circuits 210 to 240 include: a power supply circuit that supplies power to each organic EL element; a signal circuit that applies a voltage signal for controlling the power supplied to each organic EL element; a scanning circuit that switches the position where the voltage signal is applied at a certain interval; and the like.

[0210] The control circuit 250 controls the operations of the driving circuits 210 to 240 based on data including image information input from an external device or a receiving device.

[0211] In addition, Figure 8 In the embodiment, four drive circuits 210 to 240 are arranged one by one around the organic EL display panel 100 as an example, but the configuration of the drive control unit 200 is not limited to this configuration, and the number and position of the drive circuits 210 to 240 can be changed appropriately.

[0212] <Second embodiment>

[0213] In the first embodiment described above, the resin material of the second sealing layer 1082 stops wetting and spreading on the inner side (the image display area 10 side) of the inner peripheral edge portion of the circumferential groove 1022 (see Figure 2 ), due to changes in manufacturing environment such as temperature, slight changes in ink concentration, and differences in viscosity caused by the type of ink material, such as Fig. 9 As shown, the peripheral edge of the second sealing layer 1082 may enter the circumferential groove 1022. However, since the outer insulating layer 1021 acts as a dam, the peripheral edge of the second sealing layer 1082 will not extend beyond the inner end surface of the outer insulating layer 1021 and further outward (the flat portion of the top surface of the outer insulating layer 1021).

[0214] In addition, Fig. 9 In the figure, the magnification in the thickness direction is exaggerated, but in fact, the thickness of the sealing layer 108 is about 5 μm at most in the image display area 10 (refer to Figure 2), the maximum thickness at position P4 of the inner peripheral edge of the circumferential groove 1022 is about 3 μm, and it decreases sharply downward in the circumferential groove 1022, and the thickness t2 of the second sealing layer 1082 at the inner end 110a of the peripheral sealing layer 110 becomes thinner than the thickness t1 of the flat portion of the outer insulating layer 1021.

[0215] Therefore, even if the peripheral edge portion of the second sealing layer 1082 enters the circumferential groove 1022, the gap can be stably formed and positioned through the gap forming member 1101 located between the upper surface of the outer insulating layer 1021 and the lower surface of the color filter substrate 111, so that the bottom portion of the gap forming member 1101 located on the innermost side of the peripheral sealing layer 110 will not strongly press the third sealing layer 1083 of the sealing layer 108.

[0216] In addition, Fig. 9 In order to facilitate understanding, the magnification in the Z direction is made much larger than the magnification in the X direction, so the film thickness t3 of the second sealing layer 1082 at the position P4 of the inner edge of the circumferential groove 1022 appears thick. However, if the ink of the applied second sealing layer 1082 exceeds the position P4 and is applied and expanded, the ink at the outer peripheral edge will flow into the circumferential groove 1022 at once, so the film thickness t3 of the second sealing layer 1082 at the position P4 is actually very thin, and is no more than about 1 μm at most. Therefore, the height of the upper surface of the third sealing layer 1083 further outside (on the outer insulating layer 1021 side) than the position P4 becomes lower at once.

[0217] Therefore, as long as the inner end 110a of the peripheral sealing layer 110 is located at a position further outward (on the side of the outer insulating layer 1021) than position P4, even if the inner end 110a of the peripheral sealing layer 110 abuts against the third sealing layer 1083, it is restricted by the gap forming component 1101 on the outer insulating layer 1021 and the softness of the resin layer of the second sealing layer 1082 also helps. Therefore, the bottom part of the innermost gap forming component 1101 of the peripheral sealing layer 110 will not apply a pressing force that breaks through the third sealing layer 1083 of the sealing layer 108.

[0218] In this way, by providing the circumferential groove 1022 and the inner end 110a of the peripheral sealing layer 110 being located further outward (toward the outer insulating layer 1021) than the position P4 of the inner edge of the circumferential groove 1022, the thickness of the second sealing layer 1082 at the position of the inner end 110a of the peripheral sealing layer 110 can be made thinner than the thickness (film thickness t1) of the flat portion of the outer insulating layer 1021, by at least Fig.13 Compared with the conventional structure shown, the pressing force applied by the inner end of the peripheral sealing layer 110 to the third sealing layer 1083 can be suppressed, and the possibility of damage to the third sealing layer 1083 and deterioration of sealing performance can be greatly reduced.

[0219] <Summary of Effect>

[0220] The invention according to each of the above-mentioned embodiments can obtain the following effects.

[0221] (1) Since the circumferential groove 1022 is formed in the interlayer insulating layer and the interlayer insulating layer is divided into two parts, namely, the outer insulating layer 1021 and the inner insulating layer 1023, when the second sealing layer 1082 of the sealing layer 108 is formed by a coating method, the wetting and spreading of the outer peripheral portion thereof does not exceed the inner end portion (the range of position P5 to position P6) of the outer insulating layer 1021. In addition, since the inner end portion 110a of the peripheral sealing layer 110 is located in the circumferential groove 1022, the thickness of the second sealing layer 1082 at the position of the inner end portion 110a of the peripheral sealing layer 110 is thinner than the thickness of the flat portion of the outer insulating layer 1021 (including the case where the thickness of the second sealing layer 1082 is "0"), when the color filter substrate 111 is pressed, the gap forming member 1101 does not press and damage the third sealing layer 1083 of the sealing layer 108 and the sealing property can be maintained.

[0222] At this time, since the peripheral edge of the color filter substrate 111 is supported by the peripheral sealing layer 110 existing above the outer insulating layer 1021, no Fig.12 The drooping portion shown in the figure can eliminate the uneven viewing angle and improve the image quality.

[0223] (2) The interlayer insulating layer 102 formed of resin and having the property of easily absorbing moisture is covered to its outer end by the first sealing layer 1081 and the third sealing layer 1083 formed of an inorganic material that does not absorb moisture, thereby effectively preventing moisture from penetrating from the direction along the lower substrate 101.

[0224] (3) The interlayer insulating layer 102 is completely separated into an outer insulating layer 1021 and an inner insulating layer 1023 by the circumferential groove 1022, and the inner side surface and bottom of the circumferential groove 1022 are covered by the first sealing layer 1081. Therefore, even if moisture penetrates into the outer insulating layer 1021, it is blocked by the circumferential groove 1022 and the first sealing layer 1081 and is difficult to penetrate into the inner insulating layer 1023.

[0225] <Modification>

[0226] Any embodiment described above is a preferred specific example of the present invention. The numerical values, shapes, materials, components, configuration positions of components, connection methods, processes, and the order of processes shown in the embodiments are examples and can be appropriately modified without departing from the scope of the present invention.

[0227] Modifications of the organic EL display panel will now be described.

[0228] (1) In each of the above-mentioned embodiments, the outer end surface 110b of the peripheral sealing layer 110 reaches the position P2 of the flat portion of the upper surface of the outer insulating layer 1021 on a cross section perpendicular to the lower substrate 101 and crossing the circumferential groove 1022 (see Figure 2 , Fig. 9 ), but if Fig.10 As shown, the width of the peripheral sealing layer 110 may be further expanded so that the outer end 110 b thereof reaches a position P3 which is further outward than the outer peripheral end surface of the outer insulating layer 1021 .

[0229] By doing so, even if there are sealing defects such as pinholes in the first sealing layer 1081 and the third sealing layer 1083, the resin material 1102 of the peripheral sealing layer 110 can prevent moisture from directly contacting them, so it is more difficult for moisture to penetrate into the outer insulating layer 1021, thereby improving the sealing performance.

[0230] (2) In the above second embodiment (refer to Fig. 9 In the organic EL display panel 100 of FIG. 1 , when the entire structure is flexible, whenever the panel is bent, the bottom of the gap forming member 1101 located at the innermost side of the peripheral sealing layer 110 and directly above the second sealing layer 1082 formed of a resin material exerts a large pressure on the third sealing layer 1083, and there is a possibility of damaging the third sealing layer 1083. Therefore, in this case, if Fig.11 As shown, it is preferable that the inner end portion 110 a of the peripheral sealing layer 110 is formed so as to be located outside the position P5 of the inner edge portion of the flat portion of the upper surface of the outer insulating layer 1021 .

[0231] (3) In the above embodiment, as a method for forming the light-emitting layer, a wet film-forming process such as screen printing, spin coating, and inkjet is used, but the present invention is not limited thereto. For example, a dry film-forming process such as vacuum evaporation, electron beam evaporation, sputtering, reactive sputtering, ion plating, and vapor phase growth may also be used. In addition, well-known materials may be appropriately used for the materials of each component.

[0232] (4) In the above embodiment, the film forming conditions and composition of the first sealing layer 1081 are the same as those of the third sealing layer 1083 , but they do not need to be completely the same and can be appropriately modified by those skilled in the art.

[0233] In addition, generally, inorganic materials have the characteristic of being difficult to absorb moisture compared to resin materials. Therefore, as the material of the first sealing layer 1081 and the third sealing layer 1083, in addition to the above-mentioned silicon nitride (SiN), other suitable inorganic materials (such as silicon oxynitride (SiON), silicon carbide (SiC), etc.) can also be used.

[0234] (5) In the above embodiment, the color filter substrate 111 is described as the second substrate adhered to the sealing layer 108, but in addition to the color filter substrate 111, a well-known polarizing film (for example, see Japanese Patent Publication No. 7-142170, Japanese Patent Publication No. 2001-4837, etc.) can also be adhered. The above polarizing film makes it difficult for light incident from the outside and reflected inside the organic EL display panel 100 (especially the pixel electrode 103) to be transmitted to the outside, thereby increasing the clarity of the organic EL display panel 100 outdoors.

[0235] In the above embodiment, an organic material having individual luminescent colors of R, G, and B is used as the light emitting layer 105 . However, an organic material that emits only white light may be used to perform color display using the color filter substrate 111 .

[0236] (6) As shown in the above embodiment, when the substrate 101a is a flexible substrate formed of resin, a sealing film similar to the first sealing layer 1081 and the third sealing layer 1083 of the embodiment may be provided between the substrate 101a and the TFT layer 101b. According to this configuration, the entry of moisture from the substrate side can be suppressed.

[0237] (7) In the above-mentioned embodiments, each organic EL element is composed of a pixel electrode, a light-emitting layer, an electron transport layer, and an opposing electrode. However, for example, it can also be constructed to include a hole injection layer and a hole transport layer between the pixel electrode and the light-emitting layer, or it can also be constructed to include an electron injection layer between the electron transport layer and the opposing electrode.

[0238] In the above embodiment, the pixel electrode is a reflective electrode and the counter electrode is a transmissive electrode, but the pixel electrode may be a transmissive electrode and the counter electrode may be a reflective electrode, and a bottom emission type may be used.

[0239] (8) In the above embodiment, if Figure 2As shown in the figures, the structure is as follows: the end edge of any one of the first sealing layer 1081 and the third sealing layer 1083 extends to the outside than the outer peripheral end surface of the outer insulating layer 1021, and covers the top and outer side of the outer insulating layer 1021. However, as long as at least one of the first sealing layer and the third sealing layer covers the top and outer side of the outer insulating layer 1021, moisture will not easily penetrate into the outer insulating layer 1021 from the outside.

[0240] (9) In the above embodiment, spherical gap-forming members 1101 are mixed into the peripheral seal layer 110 . However, as long as a certain thickness can be reliably ensured, for example, a short fiber-shaped filler may be mixed as the gap-forming member 1101 .

[0241] (10) In the above embodiment, an organic EL display panel using an organic EL as a light-emitting layer is described. However, in addition to this, even for self-luminous display panels such as an inorganic EL panel using an inorganic EL as a light-emitting layer, a quantum dot panel using quantum dots as a light-emitting layer (for example, refer to Japanese Patent Gazette No. 2010-199067), etc., only the type of the light-emitting layer is different. The structure in which the light-emitting layer is between the pixel electrode and the opposing electrode is the same as the organic EL display panel. Through the same sealing structure as the above embodiment, the sealing performance can be improved, and the viewing angle unevenness in the peripheral part of the image display area can be eliminated, thereby obtaining a high-quality display screen.

[0242] <Supplement>

[0243] As an example of the self-luminous display panel of the present invention, the organic EL display panel and the manufacturing method thereof are described above based on the embodiments and the modified examples, but the present invention is not limited to the above-mentioned embodiments and the modified examples. Methods obtained by various modifications that can be thought of by those skilled in the art for the above-mentioned embodiments and the modified examples, and methods realized by arbitrarily combining the components and functions of the embodiments and the modified examples within the scope of the purpose of the present invention are also included in the present invention.

[0244] Industrial Applicability

[0245] The self-luminous display panel of the present invention is suitable as a display panel that can ensure good sealing properties and suppress the occurrence of image noise in the peripheral portion of the image display area.

Claims

1. A self-luminous display panel, the self-luminous display panel having an image display area and a peripheral area around the image display area in a plan view, characterized in that: The self-luminous display panel comprises: a first substrate; an insulating resin layer, disposed above the first substrate; A plurality of self-luminous elements are arranged above the insulating resin layer and located in the image display area; A sealing portion disposed above the plurality of self-luminous elements; and A second substrate is disposed on the sealing portion, The insulating resin layer is divided into an inner insulating resin layer portion and an outer insulating resin layer portion by a circumferential groove formed in the peripheral region and surrounding the image display region. The sealing portion is formed such that, in a plan view, a first sealing layer formed of an inorganic material, a second sealing layer formed of a resin material, and a third sealing layer formed of an inorganic material are stacked in order from the side close to the first substrate within a range including the image display area and reaching at most the inner side end of the outer insulating resin layer portion, and the sealing portion is formed such that the second sealing layer does not exist within a range further outside than the range, and the first sealing layer and the third sealing layer are directly stacked, The second substrate is adhered to the sealing portion via a peripheral sealing layer disposed inside the peripheral edge portion of the second substrate and a bonding layer disposed within a range surrounded by the peripheral sealing layer. On a cross section perpendicular to the main plane of the first substrate and crossing the circumferential groove, at least a portion of the peripheral sealing layer exists on the outer insulating resin layer, and the inner end of the peripheral sealing layer is located within the width of the circumferential groove and is closer to the outside than the inner edge of the circumferential groove.

2. The self-luminous display panel according to claim 1, characterized in that: The thickness of the second sealing layer is thinner than the thickness of the outer insulating resin layer portion at a position of an inner end portion of the peripheral sealing layer.

3. The self-luminous display panel according to claim 1 or 2, characterized in that: A portion of the sealing portion where the first sealing layer and the third sealing layer are directly laminated extends to cover the outer end portion of the outer insulating resin layer portion.

4. The self-luminous display panel according to claim 1 or 2, characterized in that: In a plan view, an outer end portion of the peripheral seal layer is located further outward than an outer end portion of the outer insulating resin layer portion.

5. The self-luminous display panel according to claim 1 or 2, characterized in that: The second substrate is a color filter substrate having at least red, green, and blue color filters.

6. The self-luminous display panel according to claim 1 or 2, characterized in that: The second sealing layer is formed of a coating film.

7. The self-luminous display panel according to claim 1 or 2, characterized in that: The peripheral sealing layer is formed by dispersing spherical gap-forming members in an ultraviolet curable resin material.

8. A method for manufacturing a self-luminous display panel, wherein the self-luminous display panel has an image display area and a peripheral area around the image display area in a plan view, characterized in that: The method for manufacturing the self-luminous display panel comprises: The first step is to prepare a first substrate; A second step is to form an insulating resin layer on the first substrate; A third step is to form a plurality of self-luminous elements above the insulating resin layer and in the image display area; A fourth step is to form a sealing portion covering the upper portion of the plurality of self-luminous elements; and The fifth step is to adhere the second substrate to the sealing portion. The second step includes a circumferential groove forming step of forming a circumferential groove in the peripheral region of the insulating resin layer and dividing the insulating resin layer into an inner resin layer and an outer resin layer. In the fourth step, in a plan view, within a range including the image display area and reaching at most the inner end of the outer resin layer, a first sealing layer formed of an inorganic material, a second sealing layer formed of a resin material, and a third sealing layer formed of an inorganic material are stacked in order from the side close to the first substrate, and within a range further outside than the range, the second sealing layer does not exist, and the first sealing layer and the third sealing layer are directly stacked. In the fifth step, the second substrate is adhered to the sealing portion by means of a peripheral sealing layer disposed inside the peripheral edge portion of the second substrate and a bonding layer located within a range surrounded by the peripheral sealing layer. In a cross section perpendicular to the main plane of the first substrate and crossing the circumferential groove, at least a portion of the peripheral sealing layer exists on the outer resin layer, and the inner end of the peripheral sealing layer is located within the width of the circumferential groove and is closer to the outside than the inner edge of the circumferential groove.

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