Display device

Abstract

The invention relates to a display device. The display device is provided with a flexible substrate, a first insulating layer provided on the substrate, a wiring provided on the first insulating layer, a second insulating layer covering the wiring and the first insulating layer, and a protective tape provided on the second insulating layer. The display device includes a display region and an end region having a bending region, the protective tape overlaps the bending region, and a neutral surface of a laminated structure of the base material, the first insulating layer, the wiring, the second insulating layer, and the protective tape is generated in the wiring.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2023-155514 filed on September 21, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] An embodiment of the present invention relates to a display device. Background Art

[0004] Flat panel displays such as organic electroluminescence (EL) display devices have a display panel formed by thin film transistors (TFT), organic light-emitting diodes (OLED), etc. formed on a substrate. In the past, glass substrates were used as the substrate of the display panel, but in recent years, the development of flexible displays that can bend the display panel by using resin films or the like in the substrate is underway.

[0005] As a use of flexible displays, it is considered to achieve a narrow frame by bending a portion of a display panel on which an integrated circuit (IC) and a flexible printed circuit (FPC) are mounted outside the image display area toward the back of the display area. Summary of the invention

[0006] An object of this embodiment is to provide a display device capable of improving the yield.

[0007] A display device according to one embodiment includes:

[0008] Flexible substrate;

[0009] A first insulating layer disposed on the substrate;

[0010] Wiring arranged on the first insulating layer;

[0011] a second insulating layer covering the wiring and the first insulating layer; and

[0012] a protective tape provided on the second insulating layer,

[0013] The display device comprises a display area and an end area having a bending area.

[0014] The protection band overlaps with the bending area. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] [ Figure 1 ] Figure 1 It is an overall perspective view of a display device according to an embodiment.

[0016] [ Figure 2 ] Figure 2 It is a cross-sectional view showing an example of a schematic configuration of a display device according to a comparative example.

[0017] [ Figure 3 ] Figure 3 It is a cross-sectional view showing an example of a schematic configuration of a display device according to a comparative example.

[0018] [ Figure 4 ] Figure 4 for Figure 2 An enlarged cross-sectional view of a portion of.

[0019] [ Figure 5 ] Figure 5 is a cross-sectional view of a display device according to another comparative example.

[0020] [ Figure 6 ] Figure 6 is a cross-sectional view of a display device according to another comparative example.

[0021] [ Figure 7 ] Figure 7 This is a cross-sectional view showing an example of a schematic configuration of a display device according to an embodiment.

[0022] [ Figure 8 ] Figure 8 This is a cross-sectional view showing an example of a schematic configuration of a display device according to an embodiment.

[0023] [ Fig. 9 ] Fig. 9 Graph showing the relationship between the radius of curvature and the distance from the bottom surface of the substrate to the neutral plane when the display device of the comparative example is bent.

[0024] [ Fig.10 ] Fig.10 Graph showing the relationship between the radius of curvature and the distance from the bottom surface of the substrate to the neutral plane when the display device of the comparative example is bent.

[0025] [ Fig.11 ] Fig.11 It is a partial plan view showing an example of a schematic structure of a display panel.

[0026] [ Fig.12 ] Fig.12 For along Fig.11 A cross-sectional view of the display panel taken along line A1 - A2 is shown. DETAILED DESCRIPTION

[0027] Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that the disclosed content is only an example, and appropriate changes that can be easily thought of by those skilled in the art while maintaining the main purpose of the invention are of course also included in the scope of the present invention. In addition, in order to make the description clearer, the drawings show schematic representations of the width, thickness, shape, etc. of each part compared to the actual method, but this is only an example and does not limit the interpretation of the present invention. In addition, in this specification and the drawings, for the figures that have appeared, the same figure marks are marked for the elements that are the same as the elements that have been described, and sometimes the detailed description is appropriately omitted.

[0028] The embodiments described in this specification are not general modes, but are embodiments for describing the same or corresponding special technical features of the present invention. Hereinafter, a display device according to one embodiment will be described in detail with reference to the drawings.

[0029] In the present embodiment, the first direction X, the second direction Y, and the third direction Z are orthogonal to each other, but may intersect at an angle other than 90 degrees. The direction of the arrow tip toward the third direction Z is defined as up or above, and the direction opposite to the direction of the arrow tip toward the third direction Z is defined as down or below. It should be noted that the first direction X, the second direction Y, and the third direction Z are sometimes referred to as the X direction, the Y direction, and the Z direction, respectively.

[0030] In the case of "the second component above the first component" and "the second component below the first component", the second component may be in contact with the first component or may be located away from the first component. In the latter case, a third component may be interposed between the first component and the second component. On the other hand, in the case of "the second component on the first component" and "the second component below the first component", the second component is in contact with the first component.

[0031] In addition, assuming that there is an observation position for observing the display device on the front end side of the arrow in the third direction Z, the case of observing from the observation position toward the XY plane defined by the first direction X and the second direction Y is referred to as a top view. The case of observing a cross section of the display device in the XZ plane defined by the first direction X and the third direction Z, or in the YZ plane defined by the second direction Y and the third direction Z is referred to as a cross-sectional view.

[0032] [Implementation Method]

[0033] Figure 1: is an overall perspective view of a display device according to an embodiment. The display device DSP is provided with a display area DA and a peripheral area FA provided around the display area DA on a substrate SUB1. The display device DSP has a plurality of pixels PX arranged in the display area DA. In the display device DSP, light LT of the pixels PX is emitted upward.

[0034] exist Figure 1 In the embodiment, the display panel PNL includes a substrate SUB1 and a plurality of pixels PX. The surface of the display panel PNL from which light LT is emitted is set as a surface FF. The surface on the opposite side of the surface FF in the third direction Z is set as a surface RF. The surface FF may be referred to as an emission surface, a front surface, or an upper surface, and the surface RF may be referred to as a back surface or a lower surface.

[0035] The area EA at the end of the substrate SUB1 is arranged outside the display area DA. The area near the display area DA in the area EA is referred to as the end ES11. The end of the area EA that is away from the display area DA along the second direction Y is referred to as the end ES12. The surface of the substrate SUB1 from which the light LT is emitted is referred to as the surface FL. The surface on the opposite side to the surface FL is referred to as the surface RL. The surface RL is the same surface as the surface RF. It should be noted that the area EA is also referred to as the end area of ​​the display panel PNL.

[0036] A connection portion WPD is provided in the region EA on the end ES12 side. The wiring from the display region DA extends in the connection portion WPD. The wiring from the display region DA is a scanning line or a signal line from a pixel PX, or a wiring connected to a scanning line or a signal line.

[0037] The region BND is provided between the end ES11 and the end ES12 of the region EA. The region BSF is provided between the region BND and the end ES12. The region BND is a bent region, and the region BSF is a region that is bent and turned upside down. The region BND and the region BSF will be described in detail later.

[0038] A flexible wiring substrate FPC1 is provided at the connection portion WPD of the area EA. The flexible wiring substrate FPC1 has a plurality of wirings arranged along the first direction X. The wirings of the flexible wiring substrate FPC1 are electrically connected to the connection portion WPD via an anisotropic conductive film (ACF). Thus, the wirings from the display area DA and the wirings of the flexible wiring substrate FPC1 are electrically connected.

[0039] Among the ends of the flexible wiring substrate FPC1, the end close to the connection portion WPD is defined as the end EF11. The end on the opposite side of the end EF11 along the second direction Y is defined as the end EF12. The end EF11 is closer to the end ES12 of the substrate SUB1 than the end EF12. In other words, the end EF11 is located between the end EF12 and the end ES12.

[0040] The end EF12 of the flexible wiring substrate FPC1 is electrically connected to the printed circuit substrate PCB. The end of the printed circuit substrate PCB connected to the end EF12 of the flexible wiring substrate FPC1 is referred to as the end EB11. The end on the opposite side of the end EB11 along the second direction Y is referred to as the end EB12. The end EB11 is closer to the end ES12 of the substrate SUB1 than the end EB12. In other words, the end EB11 is located between the end EB12 and the end ES12.

[0041] It should be noted that the flexible wiring board FPC1 and the printed circuit board PCB are sometimes collectively referred to as a flexible wiring board FPC. Alternatively, a configuration may be adopted in which only the flexible wiring board FPC1 is provided without providing the printed circuit board PCB.

[0042] The flexible wiring FPC1 may be provided with a driving element that outputs an image signal or a driving signal. The signal from the driving element is input to the pixel PX in the display area DA via the flexible wiring substrate FPC1. The pixel PX emits light based on the image signal and various control signals.

[0043] The substrate SUB1 includes: a flexible base material (base material BA1 described later); and a plurality of pixels PX. The base material may be formed of, for example, a resin film material, more specifically, acrylic resin (acryl), polyimide, polyethylene terephthalate, polyethylene naphthalate, etc. A plurality of pixels PX including a plurality of switching elements, a plurality of scanning lines, a plurality of signal lines, a plurality of pixel electrodes, a common electrode, a plurality of light-emitting layers, etc. are provided on the base material. The detailed structure of the pixel PX, etc. is described later.

[0044] The substrate SUB1 is flexible, so the display panel PNL is a flexible display panel, that is, the display panel PNL is a flexible display.

[0045] Here, a display device according to a comparative example will be described. Figure 2 and Figure 3 It is a cross-sectional view showing an example of a schematic configuration of a display device according to a comparative example. Figure 2 It is a cross-sectional view of a display device of a comparative example in a bent state. Figure 3 It is a cross-sectional view of a display device of a comparative example in a state before being bent.

[0046] The display device DSP includes a display panel PNL, a polarizing plate POL, an optical adhesive OCA1, a cover material CG, a protection member BPT, a protection member UVR, a protection member PRS, a protection member DST, and a flexible wiring substrate FPC.

[0047] exist Figure 2 In the display device DSP shown, the display panel PNL is bent in the region BND. By bending the display panel PNL in the region BND, the region EA including the connection portion WPD becomes smaller, and a narrow frame can be achieved.

[0048] The region BSF of the display panel PNL overlaps a portion of the display area DA in the direction opposite to the third direction Z. Between a portion of the display area DA and the region BSF, the protection member BPT, the protection member DST, and the protection member SPT are arranged in the direction opposite to the third direction Z.

[0049] A polarizing plate POL is provided on the surface FF side of the display panel PNL in contact with the display area DA. The polarizing plate POL is, for example, a circular polarizing plate. By providing the polarizing plate POL, for example, reflection of external light in the display area DA can be suppressed.

[0050] A cover material CG is provided on the polarizing plate POL by using an optical adhesive OCA 1. The cover material CG may be, for example, a thin plate of glass or plastic.

[0051] A protective component BPT is provided on the surface RF side of the display panel PNL. The surface of the protective component BPT that is in contact with the surface RF of the display panel PNL is set as a surface FB. The surface of the protective component BPT that is opposite to the surface FB is set as a surface RB. A protective component DST is provided in contact with a portion of the surface RB. The protective component BPT roughly overlaps with the display area DA of the display panel PNL. More specifically, the protective component BPT overlaps with the display area DA and a portion of the area EA.

[0052] The surface of the protection component DST that is in contact with the surface RB of the protection component BPT is defined as a surface FP. The surface of the protection component DST that is opposite to the surface FP is defined as a surface RP. The protection component SPT is provided in contact with the surface RP. The protection component SPT overlaps with the region BSF.

[0053] The surface of the protective member SPT that is in contact with the surface RP of the protective member DST is defined as a surface FS. The surface of the protective member SPT that is opposite to the surface FS is defined as a surface RS. The surface RS is in contact with the surface RF of the region BSF of the display panel PNL (the surface RL of the substrate SUB1).

[0054] The protection member BPT and the protection member SPT may be made of a plate-shaped resin material, such as a plate-shaped polyethylene terephthalate (PET). The protection member BPT and the protection member SPT are attached to the surface RF of the display panel PNL and face each other in the third direction Z with the protection member DST interposed therebetween. Thus, they have the function of protecting the display panel PNL.

[0055] The protective component DST is a component having an adhesive layer on the surface and the back, such as a double-sided tape. The protective component SPT and the protective component BPT are bonded by the protective component DST. In addition, the protective component DST is more preferably a resin material with cushioning properties. The protective component DST has the function of maintaining the interval of the bent display panel PNL at a certain level. Therefore, even if pressure in the thickness direction (the third direction Z) is applied to the display panel PNL, the curvature of the region BND is maintained within an allowable range.

[0056] The protection component UVR is provided in contact with the surface FL in the area BND of the display panel PNL. The protection component UVR has the function of protecting the bending area BND of the display panel PNL. The protection component UVR is provided in contact with the surface FL of the display panel PNL between the end of the polarizing plate POL and the end EF11 of the flexible wiring substrate FPC.

[0057] The protective component UVR may be made of, for example, a photocurable resin material. The protective component UVR is provided so as not to form a gap with the polarizing plate POL. The reason for this is that if there is a gap between the polarizing plate POL and the protective component UVR, the display panel PNL is broken from the gap during the process of bending the display panel PNL, and the wiring of the display panel PNL is disconnected.

[0058] In the vicinity of the end portion ES12 of the display panel PNL, a protection member PRS is provided in contact with the end portion ES12 , the protection member SPT, and the flexible wiring board FPC.

[0059] The protection member PRS may be made of, for example, a resin material and has a function of protecting the end portion ES12 of the display panel PNL.

[0060] Figure 4 for Figure 2 An enlarged cross-sectional view of a portion of. Figure 4 For the general Figure 2 The state of the display device DSP before being bent is shown in an enlarged view of a portion from the vicinity of the end of the polarizing plate POL to the end EF11 of the flexible wiring board FPC1.

[0061] Figure 4The display panel PNL shown in the figure includes a base material BA1, an insulating layer BPLN, lead wiring LW, and an insulating layer PLN. The insulating layer BPLN is provided to cover the base material BA1. The lead wiring LW is provided on the insulating layer BPLN. The insulating layer PLN is provided to cover the lead wiring LW and the insulating layer BPLN.

[0062] The flexible printed circuit board FPC1 is connected to the lead-out wiring LW via a contact hole provided in the insulating layer PLN.

[0063] The base material BA1 is the above-mentioned base material having flexibility. The base material BA1 may be a resin film as described above.

[0064] The lead wiring LW is a wiring formed of a metal material. The lead wiring LW is formed of, for example, a three-layer stacked structure in which titanium (Ti), aluminum (Al), and titanium (Ti) are stacked in the order described. However, the material of the lead wiring LW is not limited thereto. For example, it may be a single layer of tantalum (Ta), tungsten (W), molybdenum (Mo), copper (Cu), or silver (Ag), or a stack of these.

[0065] The insulating layer BPLN and the insulating layer PLN are formed of an elastically deformable material. The elastically deformable material is, for example, a resin insulating material such as polyimide or acrylic resin. The elastic deformation will be described in detail later. The insulating layer BPLN and the insulating layer PLN have the function of flattening the surface.

[0066] The protection member UVR includes an end portion EU11 close to the end portion EP11 of the polarizing plate POL and an end portion EU12 close to the end portion EF11 of the flexible printed circuit board FPC. The end portion EP11 and the end portion EU11 are in contact with each other.

[0067] like Figure 2 and Figure 4 As shown, the protective member UVR is provided so as not to form a gap with the polarizing plate POL. The reason is that if there is a gap between the polarizing plate POL and the protective member UVR, the display panel PNL will be broken from the gap during the process of bending the display panel PNL, and the wiring of the display panel PNL will be disconnected.

[0068] Figure 5 is a cross-sectional view of a display device according to another comparative example. Figure 5 The display device DSP shown is Figure 4 Compared with the display device DSP shown in the figure, the protective member UVR is arranged with a gap between it and the polarizing plate POL.

[0069] exist Figure 5 In the display device DSP shown in the figure, the end EU11 of the protective member UVR is spaced apart from the end EP11 of the polarizing plate POL. Figure 5In the embodiment, the reinforcing member MPT is provided so as to be in contact with the surface of the protection member BPT on the opposite side of the surface in contact with the base material BA1.

[0070] The reinforcing member MPT is formed of, for example, a metal material or a reinforced plastic material. Since the reinforcing member MPT is attached to the protective member BPT, the end EU11 of the protective member UVR is not bent.

[0071] Figure 6 is a cross-sectional view of a display device of another comparative example. Figure 4 The display device DSP shown is compared to Figure 6 The display device DSP shown is not provided with a polarizing plate POL.

[0072] Figure 4 and Figure 5 The display device DSP shown in the figure has a color filter disposed on the opposite substrate side of the display panel PNL. Figure 6 In the display device DSP shown in FIG. 1 , a color filter is provided on the array substrate side (substrate SUB1) of the display panel PNL. Figure 6 In the display device DSP shown, a polarizing plate may not be provided.

[0073] exist Figure 6 In the embodiment, the reinforcing member MPT is also attached to the protective member BPT, so that the end EU11 of the protective member UVR is not bent.

[0074] If Figure 2 When the display device DSP is bent in this way, tensile stress is generated on the convex side of the neutral plane (neutral axis) of the region BND as the bending region according to the distance from the neutral plane, and compressive stress is generated on the concave side of the neutral plane (neutral axis) of the region BND according to the distance from the neutral plane.

[0075] However, when the protective member UVR is formed of a plastically deformable material, the neutral plane control of the area BND is hardly affected. If the protective member UVR uses an elastically deformable material such as a polyimide resin material or an acrylic resin material instead of a plastically deformable material, the neutral plane control of the area BND can be achieved.

[0076] Elasticity refers to the property of deforming when stress is applied and returning to the original shape after the stress is removed. Elastic deformation refers to deformation that returns to the original shape after the stress is removed. On the other hand, plasticity refers to the property of deforming when stress is applied and not returning to the original shape even if the stress is removed. Plastic deformation refers to deformation that does not return to the original shape even if the stress is removed.

[0077] When the protection member UVR is formed of a plastically deformable material, if stress is applied to the protection member UVR and the protection member UVR is deformed, the protection member UVR will not return to its original shape even if the stress is removed. Therefore, in the display device DSP bent at the region BND, a neutral surface is generated in components other than the protection member UVR.

[0078] When the protection member UVR is formed of an elastically deformable material, even if stress is applied to the protection member UVR and the protection member UVR is deformed, the protection member UVR returns to its original shape when the stress is removed. Therefore, in the display device DSP bent at the region BND, a neutral plane is generated in the components including the protection member UVR.

[0079] However, if the protective member UVR is made of an elastically deformable material such as a polyimide resin material, a gap may be generated between the polarizing plate POL and the protective member UVR. If such a gap is generated, the end EU11 of the protective member UVR may be bent as described above.

[0080] In order to prevent a gap between the polarizing plate POL and the protective component UVR, the protective component UVR is preferably made of a plastic material. If the material is plastic, it will not recover once deformed, so the protective component UVR will not peel off from the polarizing plate POL. Therefore, in view of the close adhesion with the polarizing plate POL, the protective component UVR is more preferably a plastic deformation material than an elastic deformation material.

[0081] Figure 7 1 is a cross-sectional view showing an example of a schematic configuration of a display device according to an embodiment. Figure 7 In the display device DSP shown, a protective tape PRT is provided on the insulating layer PLN to overlap with the region BND. The protective component UVR is provided between the protective tape PRT and the flexible wiring substrate FPC1. The region other than the region BND along the second direction Y in the display panel PNL is set as a region MSG. In this embodiment, the region MSG is also referred to as a flat region.

[0082] The lower surface and upper surface of the base material BA1 are respectively set as the lower surface RBA and the upper surface FBA. The lower surface and upper surface of the insulating layer BPLN are respectively set as the lower surface RBP and the upper surface FBP. The lower surface and upper surface of the insulating layer PLN are respectively set as the lower surface RPL and the upper surface FPL. The lower surface and upper surface of the protective tape PRT are respectively set as the lower surface RPR and the upper surface FPR. The distance from the lower surface RPR to the upper surface FPR of the protective tape PRT, that is, the thickness of the protective tape PRT is set as the length tt.

[0083] The distance from the lower surface RBA of the base material BA1 to the neutral surface NS is defined as a length tn1. The distance from the neutral surface NS to the upper surface FPR of the protective tape PRT is defined as a length tn2.

[0084] The end portion of the protection tape PRT close to the end portion EU11 of the protection member UVR is referred to as the end portion ET12. The end portion on the opposite side to the end portion ET12 along the direction opposite to the second direction Y is referred to as the end portion ET11.

[0085] exist Figure 7 The display device DSP shown in the figure is also provided with a protection component UVR. However, it is arranged outside the area BND which is the bending area. Therefore, the protection component UVR does not contribute to the neutral plane control.

[0086] The length tt (thickness) of the protection tape PRT is, for example, not less than 25 μm and not more than 50 μm. However, the length tt is not limited thereto.

[0087] like Figure 7 As shown, a portion of the protection tape PRT overlaps with the region MSG. In other words, the end ET11 and the end ET12 of the protection tape PRT each overlap with the region MSG. The end of the region BND that is close to the protection component BPT is set as the end ED11. The end of the region BND that is close to the protection component SPT is set as the end ED12. The distance between the end ET11 of the protection tape PRT and the end ED11 of the region BND along the second direction Y is set as the length dov1. The distance between the end ET12 of the protection tape PRT and the end ED12 of the region BND along the second direction Y is set as the length dov2. The length dov1 and the length dov2 can each be, for example, not less than 0.1 mm and not more than 0.3 mm.

[0088] Figure 7 The display device DSP shown in the figure is configured without a polarizing plate, but the present embodiment is not limited thereto. Figure 8 This is a cross-sectional view showing an example of a schematic configuration of a display device according to an embodiment. Figure 8 The display device DSP shown in the figure is similar to the display device DSP in that it has a polarizing plate POL. Figure 7 The display devices shown have different DSPs.

[0089] The polarizing plate POL is provided in the region MSG and overlaps with the protective member BPT. The end EP11 of the polarizing plate POL is in contact with the end ET11 of the protective tape PRT.

[0090] exist Figure 8 In the structure shown, it also plays a role in Figure 7 The same effect is achieved by the composition shown.

[0091] In this embodiment, a protective tape PRT is provided in the region BND serving as a bending region. The protective tape PRT is formed of a material that is plastically deformable. Plastic deformation of the protective tape PRT does not help control of the neutral plane. When protected by the reinforcing member MPT, even if a gap is formed at the boundary between the protective tape PRT and the polarizing plate POL, it will not bend. Therefore, there is no problem in providing the protective tape PRT in the region BND.

[0092] Fig. 9 and Fig.10 : is a graph showing the relationship between the radius of curvature and the distance from the bottom surface of the substrate to the neutral plane when the display device of the comparative example is bent. In the display device of the comparative example, as described above, the protective member UVR is provided in the region BND.

[0093] Fig. 9 , the horizontal axis is the curvature radius R (mm) of the bent display device. Fig.10 , the horizontal axis is the curvature radius R (mm) of the bent display device. Fig. 9 and Fig.10 The longitudinal axis of is the distance L (μm) along the third direction Z from the lower surface RBA of the base material BA1 to the neutral plane NS. Fig. 9 for Fig.10 A partial enlarged view of .

[0094] Plot SMP0 is a plot of a stacked structure without a protective member UVR in the stacked structure of the display device DSP of the comparative example. Plots SMP1, SMP2, and SMP3 are plots of stacked structures with a protective member UVR having a thickness of 100 μm, 200 μm, and 300 μm, respectively.

[0095] like Fig. 9 As shown, in the curve SMP1, elastic deformation (ElasticDeformation) is performed until the curvature radius R reaches 70 mm, but when the curvature radius R exceeds 70 mm, it changes to plastic deformation (PlasticDeformation). That is, the yield point YP1 occurs at the curvature radius R70 mm. The distance L during elastic deformation becomes 19 (μm).

[0096] In the curve SMP0, neither elastic deformation nor plastic deformation occurs.

[0097] In the curves SMP2 and SMP3 , yield points (yield point YP2 and yield point YP3 ) occur near the curvature radius R of 100 mm.

[0098] When the bending is performed with a curvature radius R of 1 mm or less, the curves SMP1 (thickness of the protective component UVR: 100 μm) to SMP3 (thickness of the protective component UVR: 300 μm) all converge to the position of the neutral plane that is substantially the same as the curve SMP0 (no protective component UVR). Therefore, it can be said that the protective component UVR has no effect on the neutral plane control.

[0099] exist Figure 7 and Figure 8 In the display device DSP shown, a protective tape PRT is provided instead of the protective component UVR. As described above, the protective component UVR is formed of, for example, a photocurable resin material. The process of forming the resin material includes: a process of coating the resin material; and a process of curing after coating. In the coating process, defects may occur due to the generation of bubbles, jumping of the resin, etc. Therefore, compared with forming the protective component UVR as a resin material, sticking the protective tape PRT has the advantage of improving the yield.

[0100] Here, the pixel PX of the display panel PNL is described in further detail.

[0101] Fig.11 1 is a partial top view showing an example of a schematic structure of a display panel. A plurality of pixels PX include a pixel PXR that emits red light, a pixel PXG that emits green light, and a pixel PXB that emits blue light. The pixel PXR, the pixel PXG, and the pixel PXB are also referred to as the first pixel, the second pixel, and the third pixel, respectively. The pixel PXR and the pixel PXB are arranged adjacent to each other along the first direction X and the second direction Y. The pixel PXG and the pixel PXB are arranged adjacent to each other along the first direction X and the second direction Y. The pixel PXB and the pixel PXR are arranged adjacent to each other along the first direction, and the pixel PXB and the pixel PXG are arranged adjacent to each other along the second direction Y.

[0102] Fig.12 For along Fig.11 A cross-sectional view of the display panel taken along line A1 - A2 is shown.

[0103] The substrate BA1 may be made of a resin film material as described above. For example, acrylic resin, polyimide, polyethylene terephthalate, polyethylene naphthalate, etc. may be used as the resin film material, and any one of them may be formed by laminating a single layer or multiple layers.

[0104] An insulating layer UC1 is provided on the base material BA1. The insulating layer UC1 is formed by, for example, a silicon oxide film and a silicon nitride film as a single layer or a stacked layer.

[0105] A light shielding layer BM may be provided on the insulating layer UC1 so as to overlap with the transistor Tr. The light shielding layer BM suppresses changes in transistor characteristics caused by the intrusion of light from the back side of the channel of the transistor Tr. When the light shielding layer BM is formed of a conductive layer, a back gate effect can also be provided to the transistor Tr by providing a predetermined potential.

[0106] An insulating layer UC2 is provided to cover the insulating layer UC1 and the light shielding layer BM. As the material of the insulating layer UC2, the same material as that of the insulating layer UC1 can be used. The insulating layer UC2 can be made of a material different from that of the insulating layer UC1. For example, the insulating layer UC1 can be made of silicon oxide, and the insulating layer UC2 can be made of silicon nitride. The insulating layers UC1 and UC2 are collectively referred to as the insulating layer UC.

[0107] A transistor Tr is provided on the insulating layer UC. The transistor Tr includes a semiconductor layer SC, an insulating layer GI, a gate electrode GE (scanning line GL), an insulating layer ILI, a source electrode SE (signal line SL), and a drain electrode DE. The transistor Tr is a thin film transistor (TFT).

[0108] As the semiconductor layer SC, amorphous silicon, polycrystalline silicon, or an oxide semiconductor is used.

[0109] As the insulating layer GI, for example, silicon oxide or silicon nitride is provided as a single layer or in a stacked form.

[0110] As the gate electrode GE, for example, molybdenum-tungsten alloy (MoW) is used. The gate electrode GE may be formed integrally with the scanning line GL.

[0111] An insulating layer ILI is provided to cover the semiconductor layer SC and the gate electrode GE. The insulating layer ILI is formed by, for example, a silicon oxide layer or a silicon nitride layer as a single layer or in a stacked manner.

[0112] A source electrode SE and a drain electrode DE are provided on the insulating layer ILI. The source electrode SE and the drain electrode DE are connected to the source region and the drain region of the semiconductor layer SC through contact holes provided in the insulating layer ILI and the insulating layer GI, respectively. The source electrode SE may be formed integrally with the signal line.

[0113] An insulating layer PAS is provided to cover the source electrode SE, the drain electrode DE, and the insulating layer ILI. An insulating layer PLL is provided to cover the insulating layer PAS.

[0114] The insulating layer PAS is formed using an inorganic insulating material. Examples of the inorganic insulating material include silicon oxide or silicon nitride formed into a single layer or a stacked layer. The insulating layer PLL is formed using an organic insulating material. Examples of the organic insulating material include resin insulating materials such as polyimide and acrylic resin. By providing the insulating layer PLL, the step difference caused by the transistor Tr can be flattened.

[0115] An anode AD is provided on the insulating layer PLL. The anode AD is connected to the drain electrode DE via a contact hole provided in the insulating layer PAS and PLL. The anode provided in the pixel PXR is referred to as the anode ADR, the anode provided in the pixel PXB is referred to as the anode ADB, and the anode provided in the pixel PXG is referred to as the anode ADG. When there is no need to distinguish between the anode ADR, the anode ADG, and the anode ADB, they are simply referred to as the anode AD.

[0116] The anode AD may be formed of, for example, a laminate of a reflective electrode and a transparent electrode. The reflective electrode is formed of a conductive material with high reflectivity, such as silver (Ag) or aluminum (Al). The transparent electrode is formed of, for example, indium tin oxide (ITO) or indium zinc oxide (IZO).

[0117] In this embodiment, the structure from the base material BA1 to the insulating layer PLL is referred to as a backplane BPS.

[0118] Banks BK (also referred to as protrusions or ribs) are provided between adjacent anodes AD. The same organic material as that of insulating layer PLL is used as a material of banks BK. Banks BK are opened to expose a portion of anodes AD.

[0119] The opening provided in the pixel PXR is referred to as the opening OPR, the opening provided in the pixel PXB is referred to as the opening OPB, and the opening provided in the pixel PXG is referred to as the opening OPG. When there is no need to distinguish between the opening OPR, the opening OPB, and the opening OPG, they are simply referred to as the opening OP.

[0120] The end of the opening OP is preferably a gently tapered shape when viewed in cross section. If the end of the opening OP is a steep shape, poor coverage will occur in the organic EL layer ELY formed later.

[0121] The organic EL layer ELY is provided overlapping with the anode AD and between the adjacent banks BK. The organic EL layer ELY includes a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. The organic EL layer ELY may further include an electron blocking layer and a hole blocking layer as required.

[0122] The organic EL layer provided in the pixel PXR is referred to as the organic EL layer ELYR, the organic EL layer provided in the pixel PXB is referred to as the organic EL layer ELYB, and the organic EL layer provided in the pixel PXG is referred to as the organic EL layer ELYG. When there is no need to distinguish the organic EL layer ELYR, the organic EL layer ELYG, and the organic EL layer ELYB, they are simply referred to as the organic EL layer ELY.

[0123] A cathode CD is provided on the organic EL layer ELY. The cathode CD is formed using, for example, a magnesium-silver alloy (MgAg) film, a single-layer film of silver (Ag), a laminated film of silver (Ag) and a transparent conductive material, etc. The transparent conductive material may be, for example, indium tin oxide (ITO), indium zinc oxide (IZO), etc.

[0124] An insulating layer SEY is provided to cover the cathode CD. The insulating layer SEY has a function of preventing moisture from invading the organic EL layer ELY from the outside. As the insulating layer SEY, a layer with high gas barrier properties is preferred. As the insulating layer SEY, for example, an insulating layer in which an organic insulating layer is sandwiched between two inorganic insulating layers containing nitrogen can be cited. As the material of the organic insulating layer, resin insulating materials such as polyimide and acrylic resin can be cited. As the material of the inorganic insulating layer containing nitrogen, for example, silicon nitride and aluminum nitride can be cited.

[0125] Fig.12 The insulating layer PLL shown is equivalent to Figure 7 The insulating layer BPLN is shown. Fig.12 The insulating layer SEY shown is equivalent to Figure 7 The insulating layer PLN is shown.

[0126] The light emitted in the organic EL layer ELY is extracted upward via the cathode CD. That is, the display device DSP (display panel PNL) of the present embodiment has a top emission structure.

[0127] Several embodiments of the present invention have been described, but these embodiments are provided as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without exceeding the scope of the invention. These embodiments and their variations are included in the scope and purpose of the invention, and are included in the invention described in the claims and their equivalents.

Claims

1. A display device comprising: Flexible substrate; A first insulating layer disposed on the substrate; Wiring arranged on the first insulating layer; a second insulating layer covering the wiring and the first insulating layer; and a protective tape provided on the second insulating layer, The display device comprises a display area and an end area having a bending area. The protection band overlaps the bending area.

2. The display device according to claim 1, wherein: The protective tape is formed of an elastically deformable material and an adhesive layer.

3. The display device according to claim 2, wherein: The elastically deformable material is a resin insulating material such as polyimide or acrylic resin.

4. The display device according to claim 1, wherein: The substrate is a resin film material of acrylic resin, polyimide, polyethylene terephthalate, or polyethylene naphthalate.

5. The display device according to claim 1, wherein: The first insulating layer and the second insulating layer are each formed of an elastically deformable material.

6. The display device according to claim 5, wherein: The elastically deformable material is a resin insulating material such as polyimide or acrylic resin.

7. The display device according to claim 1, wherein: The wiring is formed of a single layer or a stack of titanium (Ti), aluminum (Al), tantalum (Ta), tungsten (W), molybdenum (Mo), copper (Cu), or silver (Ag).

8. The display device according to claim 1, wherein: The area of ​​the display device other than the bending area is made a flat area, A portion of the guard band overlaps the flat area.

9. The display device according to claim 1, further comprising a plurality of pixels arranged in the display area, Each of the plurality of pixels has an organic EL layer.

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