CN113658515A

CN113658515A - Display substrate, manufacturing method thereof and display panel

Info

Publication number: CN113658515A
Application number: CN202110975520.4A
Authority: CN
Inventors: 王亚明; 陈立强; 王研鑫; 廖川东; 王佳丽; 茹巧巧; 张少雄; 庞孟媛
Original assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Priority date: 2021-08-24
Filing date: 2021-08-24
Publication date: 2021-11-16

Abstract

The embodiment of the disclosure discloses a display substrate, a manufacturing method thereof and a display panel, relates to the technical field of display, and is used for improving the bending performance of a bending area of the display substrate and solving the problem that devices in the bending area are easy to damage. The display substrate comprises a flexible substrate; a display device disposed on the flexible substrate; and a filler. The surface of the flexible substrate, which is far away from the display device, is provided with a concave structure, and the concave structure is at least positioned in the bending area; the filler is filled in the concave structure, and the elastic modulus of the filler is smaller than that of the flexible substrate. The display substrate provided by the disclosure has the advantages that the bending performance of the bending area of the display substrate is improved, the neutral layer position of the bending area of the display substrate is enabled to move upwards, so that the metal wiring and the packaging layer in the bending area are closer to the neutral layer, the tensile stress of the metal wiring and the packaging layer in the bending area is reduced, and the device in the bending area is prevented from being damaged.

Description

Display substrate, manufacturing method thereof and display panel

Technical Field

The disclosure relates to the field of display technologies, and in particular, to a display substrate, a manufacturing method thereof, and a display panel.

Background

With the development of self-luminous display technology, such as OLED (Organic Light-Emitting Diode) display panels, QLED (Quantum Dot Light Emitting Diodes) display panels, Micro LED (Micro Light Emitting Diodes) display panels, etc., due to the characteristics of good flexibility, high contrast and thinness, they have become research hotspots of people, especially flexible display panels, and are increasingly applied to various fields.

The flexible display panel generally has a bending region, and can realize folding or sliding display. However, in the related art, the stress of the flexible display panel during bending is too large, and a problem of poor display is likely to occur after the flexible display panel is bent for a plurality of times.

Disclosure of Invention

The present disclosure is directed to a display substrate, a method for manufacturing the same, and a display panel, which are used to improve the bending performance of a bending region of the display substrate and to solve the problem that devices in the bending region are easily damaged.

In order to achieve the above object, the present disclosure provides the following technical solutions:

in one aspect, some embodiments of the present disclosure provide a display substrate having a bending region, the display substrate including: a flexible substrate; a display device disposed on the flexible substrate; and a filler. A concave structure is arranged on the surface of the flexible substrate far away from the display device, and the concave structure is at least positioned in the bending area; and the filler is filled in the concave structure, and the elastic modulus of the filler is smaller than that of the flexible substrate.

In some embodiments, the display substrate further has at least one non-bending region adjacent to the bending region, and the recessed structure is further located in a region of the non-bending region close to the bending region.

In some embodiments, the direction from the inflection region toward the non-inflection region is a first direction; the size of the area of the non-bending area close to the bending area in the first direction is less than or equal to 0.2 times of the size of the bending area in the first direction.

In some embodiments, the recessed feature extends through the flexible substrate.

In some embodiments, the depth of the recessed feature is T of the thickness of the flexible substrate₁Multiple, wherein, T is more than or equal to 0.25₁＜1。

In some embodiments, the flexible substrate includes a plurality of layers of substrates sequentially stacked in a direction close to the display device; the recessed structure penetrates through at least one layer of substrate, and the elastic modulus of the at least one layer of substrate is smaller than that of the substrate which is not penetrated in the multilayer substrate.

In some embodiments, the number of the substrates is two, and the flexible base further comprises a buffer layer between the two substrates; the concave structure penetrates through the substrate, far away from the display device, of the two layers of substrates.

In some embodiments, the recessed feature comprises at least one hole and/or at least one groove; wherein the cross section of at least one hole is in any one of a rectangular shape, a semicircular shape, a semi-elliptical shape, a trapezoidal shape and a triangular shape, and the cross section is a section parallel to the axial direction of the hole; and/or the cross section of at least one groove is in the shape of any one of rectangle, semicircle, semi-ellipse, trapezoid and triangle, and the cross section is a section perpendicular to the extending direction of the groove.

In some embodiments, the recessed feature comprises a plurality of holes, the plurality of holes being evenly spaced.

In some embodiments, the recessed structure includes a plurality of grooves, each of the plurality of grooves is sequentially arranged along a first direction, and each of the plurality of grooves extends along a second direction crossing the first direction.

In some embodiments, the filler has an elastic modulus T of the elastic modulus of the flexible substrate₂Multiple, wherein, T is more than or equal to 0.06₂＜1。

In some embodiments, the material of the filler is a photo-curable glue or a thermal-curable glue.

In some embodiments, the display panel further comprises a glue layer located on a side of the flexible substrate and the filler which is away from the display device as a whole; and a back film positioned on one side of the adhesive layer far away from the display device; the glue layer and the filler are made of the same material and are formed through a one-time composition process; or the filler is made of optical adhesive, and the adhesive layer is made of pressure-sensitive adhesive.

In another aspect, a display panel is provided, which includes the display substrate.

In another aspect, a method for manufacturing a display substrate is provided, the display substrate having a bending region; the manufacturing method comprises the following steps: providing a flexible substrate; forming a display device on a flexible substrate; a concave structure is arranged on the surface of the flexible substrate far away from the display device, and the concave structure is at least positioned in the bending area; and filling filler in the recessed structure, wherein the elastic modulus of the filler is smaller than that of the flexible substrate.

The display substrate, the manufacturing method thereof and the display panel provided by the disclosure have the following beneficial effects:

the display substrate comprises a flexible substrate, a display device and a filler, wherein the display device and the filler are arranged on the flexible substrate, the flexible substrate is far away from the display device, a concave structure is arranged on the surface of the display device and at least located in a bending area, the filler is filled in the concave structure, and the elastic modulus of the filler is smaller than that of the flexible substrate, so that the bending stress of the display substrate in the bending area can be reduced, the bending performance of the display substrate is improved, meanwhile, the neutral layer of the display substrate can be moved upwards, the metal wiring and the packaging layer in the bending area are closer to the neutral layer, the tensile stress of the metal wiring and the packaging layer in the bending area is reduced, the device in the bending area is prevented from being damaged, and the problem that the device in the bending area is easy to damage is solved.

The manufacturing method of the display substrate and the display panel provided by the present disclosure at least include similar technical effects to those of the display substrate provided by the above technical solutions, and are not described herein again.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

FIG. 1 is a block diagram of a display substrate according to some embodiments;

FIG. 2 is a block diagram of another display substrate according to some embodiments;

FIG. 3 is a block diagram of yet another display substrate according to some embodiments;

FIG. 4 is a block diagram of yet another display substrate according to some embodiments;

FIG. 5 is a top view of a display substrate according to some embodiments;

FIG. 6 is a top view of yet another display substrate according to some embodiments;

FIGS. 7A-7E are cross-sectional views of different recess structures along the thickness direction of the display substrate;

FIG. 8 is a block diagram of yet another display substrate according to some embodiments;

FIG. 9 is a block diagram of yet another display substrate according to some embodiments;

FIG. 10A is a stress cloud of an encapsulation layer of a display substrate according to some embodiments;

FIG. 10B is a stress cloud of an encapsulation layer of yet another display substrate according to some embodiments;

FIG. 10C is a stress cloud of an encapsulation layer of yet another display substrate according to some embodiments;

FIG. 11 is a stress comparison graph of the packaging layers of the three display substrates shown in FIGS. 10A-10C;

FIG. 12 is a block diagram of a display panel according to some embodiments;

FIG. 13 is a block diagram of a display device according to some embodiments;

FIG. 14 is a flow chart of a method of fabricating a display substrate according to some embodiments;

FIG. 15 is a flow chart of another method of fabricating a display substrate according to some embodiments;

fig. 16A to 16C are structural views corresponding to respective steps in a method of manufacturing a display substrate according to some embodiments;

FIG. 17 is a flow chart of yet another method of fabricating a display substrate according to some embodiments;

fig. 18A to 18C are structural views corresponding to respective steps in a method of manufacturing a display substrate according to some embodiments.

Detailed Description

Technical solutions in some embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments provided by the present disclosure belong to the protection scope of the present disclosure.

Unless the context requires otherwise, throughout the description and the claims, the term "comprise" and its other forms, such as the third person's singular form "comprising" and the present participle form "comprising" are to be interpreted in an open, inclusive sense, i.e. as "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" and the like are intended to indicate that a particular feature, structure, material, or characteristic associated with the embodiment or example is included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be included in any suitable manner in any one or more embodiments or examples.

The use of "adapted to" or "configured to" herein is meant to be an open and inclusive language that does not exclude devices adapted to or configured to perform additional tasks or steps.

In the following, the terms "first", "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of the present disclosure, "a plurality" means two or more unless otherwise specified.

Example embodiments are described herein with reference to cross-sectional and/or plan views as idealized example figures. In the drawings, the thickness of layers and regions are exaggerated for clarity. Variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, the exemplary embodiments should not be construed as limited to the shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, an etched region shown as a rectangle will typically have curved features. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of the exemplary embodiments.

Referring to fig. 1, some embodiments of the present disclosure provide a display substrate 100, the display substrate 100 has a bending region a1, and the display substrate 100 includes a flexible substrate 110 and a display device 120; the flexible substrate 110 is configured to carry a display device 120.

The display device 120 may include a display function layer 121 and an encapsulation layer 122. As shown in fig. 8, the display functional layer 121 is located on one side of the flexible substrate 110. The encapsulation layer 122 is located on the side of the display functional layer 121 remote from the flexible substrate 110. As shown in fig. 9, the display function layer 121 includes a light emitting device and a pixel driving circuit including a plurality of thin film transistors 1210 disposed on the flexible substrate 110 at each sub-pixel. The light emitting device includes an anode (anode)1211, a light emitting function layer 1212, and a cathode (cathode)1213, and the anode 1211 is electrically connected to a drain of the thin film transistor 1210, which is used as a driving transistor, among the plurality of thin film transistors 1210.

In some examples, the light emitting functional layer 1212 includes a light Emitting Layer (EL). In other examples, the light emitting function layer 1212 may include one or more of an Electron Transport Layer (ETL), an Electron Injection Layer (EIL), a Hole Transport Layer (HTL), and a Hole Injection Layer (HIL) in addition to the light emitting layer. In the case where the display substrate 100 is an organic electroluminescent display substrate, the light-emitting layer is an organic light-emitting layer. In the case where the display substrate 100 is a quantum dot electroluminescent display substrate, the light-emitting layer is a quantum dot light-emitting layer.

The Encapsulation layer 122 may be a Thin Film Encapsulation (TFE), or may be an Encapsulation substrate. The encapsulation layer 122 is configured to encapsulate the display function layer 121 to block water and oxygen, and to prevent water and oxygen from entering the display function layer 121 and causing the display function layer 121 to fail. In some examples, the encapsulation layer 122 includes a first inorganic layer, an organic layer, and a second inorganic layer sequentially disposed from bottom to top, and of course, the encapsulation layer 122 may further include more inorganic layers and organic layers.

The structure of the flexible substrate 110 includes a plurality of structures, and the arrangement may be selected according to actual situations. For example, the flexible substrate 110 may be formed as a single layer, a double layer, or a multi-layer structure.

In some examples, as shown in fig. 1, the flexible substrate 110 is a single layer structure. The flexible substrate 110 may be selected from PET (Polyethylene terephthalate), PEN (Polyethylene naphthalate), PI (Polyimide), and the like, which are not limited herein.

In other examples, the flexible substrate 110 is a multi-layer structure. For example, the flexible substrate 110 may include a PI (Polyimide) layer, an inorganic layer, and a PI (Polyimide) layer, which are sequentially disposed to overlap.

With continued reference to fig. 1, the surface of the flexible substrate 110 away from the display device 120 is provided with a concave structure 130, and the concave structure 130 is located at least in the bending region a 1. The display substrate 100 further includes a filler 1300 filled in the recessed structure 130, and an elastic modulus of the filler 1300 in the recessed structure 130 is smaller than an elastic modulus of the flexible substrate 110.

The elastic modulus represents the rigidity of the material, and is an index of the reaction material for resisting elastic deformation, and the small elastic modulus means that the material is easy to deform after being subjected to external force.

Some embodiments of the present disclosure provide a display substrate 100 including a flexible substrate, a display device disposed on the flexible substrate, and a filler, since the surface of the flexible substrate 110 far from the display device 120 is provided with the concave structures 130, the concave structures 130 are located at least in the bending region a1, and the filler 1300 is filled in the recess structure 130, the elastic modulus of the filler 1300 is smaller than that of the flexible substrate 110, therefore, the bending stress of the display substrate 100 in the bending region a1 can be reduced, the bending performance of the display substrate 100 can be improved, and the position of the neutral layer of the display substrate 100 can be shifted upwards, thereby, the metal wires and the packaging layer in the bending area A1 are closer to the neutral layer, the tensile stress of the metal wires and the packaging layer in the bending area A1 is reduced, so as to prevent the device in the bending area A1 from being damaged, and improve the problem that the device in the bending area A1 is easy to be damaged.

It should be noted that, during the bending process of the display substrate 100, the outer film layer is stretched, the inner film layer is compressed, a transition layer which is neither in tension nor in compression exists between the outer film layer and the inner film layer, the stress is almost equal to zero, and the transition layer is the aforementioned neutral layer. In some embodiments of the present disclosure, by providing the recessed structure 130 on the surface of the flexible substrate 110 far from the display device 120 and filling the filler 1300 in the recessed structure 130, the position of the neutral layer in the bending region a1 in the display substrate 100 is moved upward, so that the metal traces and the encapsulation layer in the bending region a1 are closer to the neutral layer, the tensile stress of the metal traces and the encapsulation layer in the bending region a1 is reduced, and the device in the bending region a1 is prevented from being damaged due to the bending of the display substrate 100.

The above-mentioned "the concave structure 130 is located at least at the bending region a 1", and includes: recessed feature 130 is located entirely at inflection region a1, and recessed feature 130 is located in other regions besides inflection region a 1.

In some examples, the entire area of the display substrate 100 is the bending region a1, and the recessed structures 130 are all located in the bending region a1, as can be seen in fig. 1, in which case the display substrate 100 can be used to form a roll-to-roll display product.

In other examples, referring to fig. 2, the display substrate 100 further has at least one non-bending region a2 adjacent to the bending region a 1. At this time, the recessed structure 130 may be located entirely in the bending region a1, or may be located in other regions besides the bending region a1, such as a part of the non-bending region a2 in fig. 2.

For example, as shown in fig. 2, the display substrate 100 has two non-bending regions a2, a first non-bending region a21 and a second non-bending region a22 are respectively located at two opposite sides of the bending region a1, and taking the orientation shown in fig. 2 as an example, the first non-bending region a21 is located at the left side of the bending region a1, and the second non-bending region a22 is located at the right side of the bending region a1, in this case, the display substrate 100 may be used to form a foldable display product.

In some embodiments, when the display substrate 100 further has at least one non-bending region a2 adjacent to the bending region a1, as shown in fig. 2, the concave structure 130 is further located in a region d of the non-bending region a2 close to the bending region a 1. That is, the recess structure 130 includes a portion located in the inflection region a1 and a portion located in the region d of the non-inflection region a2 beyond the inflection region.

Some embodiments of the present disclosure provide a display substrate 100, wherein a concave structure 130 is disposed on a surface of the flexible substrate 110 away from the display device 120, and the concave structure 130 includes a portion located in the bending region a1 and a portion located in the region d beyond the bending region in the non-bending region a2, so that the bending performance of the bending region a1 of the display substrate 100 is better.

In some embodiments, as shown in fig. 2, a direction pointing from the inflection region a1 to the non-inflection region a2 is a first direction (i.e., an X direction as shown in fig. 2), and a dimension of a region d of the non-inflection region a2 near the inflection region a1 in the first direction is less than or equal to 0.2 times a dimension of the inflection region a1 in the first direction.

The size of the bending region a1 in the first direction mainly depends on the bending radius of the display substrate 100. The person skilled in the art can set the dimension of the region d of the above-mentioned non-bending region a2 close to the bending region a1 in the first direction according to the dimension of the bending region a1 in the first direction.

In some embodiments, a dimension of an area d of the non-bending region a2 adjacent to the bending region a1 in the first direction X is 2mm to 10 mm. For example, the size of the region d of the non-inflection region a2 adjacent to the inflection region a1 in the first direction X may be 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, or the like.

In this embodiment, when the size of the region d in the non-bending region a2, which is close to the bending region a1, in the first direction X is equal to or close to 2mm, the bending performance of the display substrate in the bending region can be improved to some extent, and at the same time, the arrangement region of the concave structure is made smaller, and the overall structural strength of the display substrate 100 is higher. When the size of the region d of the non-bending region a2 close to the bending region a1 in the first direction X is equal to or close to 10mm, the bending performance of the display substrate in the bending region can be greatly improved, and the overall structural strength of the display substrate 100 can be ensured to a certain extent since the arrangement region of the concave structure is not too large.

In some embodiments, as shown in FIG. 2, recessed feature 130 extends through flexible substrate 110. At this time, the filler 1300 in the recess structure 130 may be a material with a lower modulus of elasticity than the flexible substrate 110, such as a low modulus PI, a low modulus PET, or a low modulus PEN, and is not limited herein, as long as the requirement that the filler 1300 in the recess structure 130 has a lower modulus of elasticity than the flexible substrate 110 is satisfied.

According to the display substrate 100 provided by some embodiments of the present disclosure, the concave structure 130 is disposed on the surface of the flexible substrate 110 away from the display device 120, the concave structure 130 penetrates through the flexible substrate 110, and the filler 1300 made of a material such as a low-modulus PI, a low-modulus PET, or a low-modulus PEN having an elastic modulus lower than that of the flexible substrate 110 is filled in the concave structure 130, so that the bending performance of the bending region a1 of the display substrate 100 is better.

It will be appreciated by those skilled in the art that the greater the modulus of elasticity, the less deformable the material and the greater the stiffness, the greater the stiffness. That is, in the bending region a1 portion of the display substrate 100, including the flexible substrate 110 with a high elastic modulus, the flexible substrate 110 can be ensured to have a good supporting capability for the display device 120; the inclusion of the filler 1300 with a lower elastic modulus in the bending region a1 portion of the display substrate 100 can improve the bending performance of the bending region a 1. The depth H of the recess structure 130 and the thickness H of the flexible substrate 110 can be selected according to actual requirements.

In some embodiments, as shown in FIG. 3, the depth H of the recessed feature 130 is T of the thickness H of the flexible substrate 110₁Multiple, wherein, T is more than or equal to 0.25₁Is less than 1. In this case, it is possible to ensure that the flexible substrate 110 has a good supporting capability for the display device 120, and to improve the bending performance of the bending region a 1.

In this embodiment, when the depth H of the recess structure 130 is equal to or close to 0.25 times the thickness H of the flexible substrate 110, the bending performance of the bending region of the display substrate can be improved to a certain extent, and meanwhile, the arrangement depth of the recess structure is smaller, and the overall structural strength of the display substrate 100 is higher. When the depth H of the concave structure 130 is close to 1 time of the thickness H of the flexible substrate 110, the bending performance of the display substrate in the bending region can be greatly improved, and the overall structural strength of the display substrate 100 can be ensured to a certain extent because the concave structure does not penetrate through the flexible substrate 110.

Illustratively, the thickness H of the flexible substrate 110 ranges from 10um to 20um, and the depth H of the recess structure 130 ranges from 5un to 15 um. For example, the thickness H of the flexible substrate 110 may be 10um, 15um, or 20 um. The depth h of the recess structure 130 may be 5um, 10um, 15 um.

In some embodiments, the thickness H of the flexible substrate 110 is 20um, and the depth H of the recess structure 130 is 5 um; alternatively, the thickness H of the flexible substrate 110 is 20um, and the depth H of the recess structure 130 is 10 um; alternatively, the thickness H of the flexible substrate 110 is 15 um. The depth h of the recess 130 is 5 um.

In some embodiments, the flexible substrate 110 includes a plurality of layers of substrates sequentially stacked in a direction close to the display device 120. The recessed structure 130 penetrates at least one layer of the substrate having a smaller elastic modulus than that of the substrate that is not penetrated in the multi-layer substrate.

In this embodiment, since the concave structure 130 penetrates at least one of the plurality of substrates, so that the bending region a1 portion of the display substrate 100 includes both the filler 1300 with a low elastic modulus and the flexible substrate 110 with a high elastic modulus, the bending performance of the display substrate in the bending region can be improved, and the overall structural strength of the display substrate 100 can be ensured to a certain extent.

In some embodiments, as shown in fig. 4, the flexible base 110 includes a first substrate 1101 and a second substrate 1102 sequentially stacked in a direction close to the display device 120. In this case, the flexible base 110 may further include a buffer layer 1103 located between the two substrates, and the recess structure 130 penetrates through a first substrate 1101 of the two substrates, which is far from the display device 120.

Wherein the elastic modulus of the first substrate 1101 is less than the elastic modulus of the second substrate 1102.

The first substrate 1101 and the second substrate 1102 may be made of PET (Polyethylene terephthalate), PEN (Polyethylene naphthalate) or PI (Polyimide), and the buffer layer 1103 may be made of one of SiO2 and SiNx.

In some embodiments, as shown in fig. 3 and 4, recessed feature 130 includes at least one hole 1301 and/or at least one groove 1302.

It should be noted that the above-mentioned "the recess structure 130 includes at least one hole 1301 and/or at least one groove 1302" means: in some examples, the recess structure 130 includes at least one hole 1301, that is, as shown in fig. 5, fig. 5 is a top view of a display substrate 100 of some embodiments; in other examples, the recess structure 130 includes at least one groove 1302, as shown in fig. 6, and fig. 6 is a top view of a display substrate 100 according to still other embodiments; in still other examples, the recessed feature 130 includes at least one hole 1301 and at least one slot 1302.

The shape, number, depth and arrangement of the holes 1301 and the grooves 1302 may be selected according to actual situations, which is not limited in the embodiments of the present disclosure.

In some embodiments, as shown in fig. 5, the recess structure 130 includes a plurality of holes 1301, and the plurality of holes 1301 may be uniformly arranged in an array shape, so that the bending performance of the bending region is better and more stable.

Wherein, along the thickness direction of the display substrate 100, the orthographic projection of each hole 1301 may be rectangular in shape, i.e., as shown in fig. 5. Alternatively, the orthographic projection of each hole 1301 in the thickness direction of the display substrate 100 is shaped as a diamond. Of course, the orthographic projection shape of each hole 1301 along the thickness direction of the display substrate 100 can also be other irregular shapes.

In some examples, the cross-section of at least one hole 1301 is any one of rectangular, semicircular, semi-elliptical, trapezoidal, and triangular in shape, and the cross-section is a section parallel to the axial direction of the hole. Of course, the shape of the cross-section of the at least one hole 1301 may also be other irregular shapes.

When the flexible substrate 110 is a single-layer structure, a plurality of holes 1301 may penetrate through the flexible substrate 110, as shown in fig. 9; alternatively, as shown in FIG. 3, a plurality of holes 1301 do not extend through the flexible substrate 110. When the flexible base 110 includes a first substrate 1101, a buffer layer 1103, and a second substrate 1102 sequentially stacked in a direction close to the display device 120, a plurality of holes 1301 may penetrate the first substrate 1101, that is, as shown in fig. 4; also, the plurality of holes 1301 may not extend through the first substrate 1101.

It can be understood by those skilled in the art that when the recess structure 130 includes a plurality of holes 1301, the filler 1300 is filled in the plurality of holes 1301, and the elastic modulus of the filler 1300 is smaller than that of the flexible substrate 110.

In some embodiments, as shown in fig. 6, the recess structure 130 includes a plurality of grooves 1302, and the plurality of grooves 1302 are uniformly arranged, so that the bending performance of the bending region is better and more stable.

Further, a direction directed to the non-bending region a2 by the bending region a1 is a first direction (i.e., an X direction as shown in fig. 6), the plurality of grooves 1302 are all arranged in sequence along the first direction X, and the plurality of grooves 1302 extend along a second direction Y intersecting the first direction X. The first direction and the second direction are crossed, and the first direction and the second direction are perpendicular to each other, or an included angle formed by the intersection of the first direction and the second direction is an acute angle. In the drawings of the embodiments of the present disclosure, the first direction and the second direction are perpendicular to each other as an example.

Fig. 7A to 7E are cross-sectional views of the recess structure 130 along the thickness direction of the display substrate 100.

In some examples, as shown in fig. 7A to 7E, the shape of the cross section of at least one groove 1302, which is a section perpendicular to the extending direction of the groove, may be any one of rectangular, semicircular, semi-elliptical, trapezoidal, and triangular. Of course, the shape of the cross-section of the at least one groove 1302 may also be other irregular shapes.

In some examples, as shown in fig. 7A-7D, the plurality of slots 1302 are sequentially spaced apart along a second direction that intersects the first direction. The spacing distance between two adjacent slots 1302 is not limited in the embodiments of the present disclosure.

In other examples, as shown in FIG. 7E, at least two of the plurality of slots 1302 have a triangular cross-sectional shape, with ends of adjacent two of the at least two slots 1302 connected.

When the flexible substrate 110 is a single-layer structure, the plurality of grooves 1302 may penetrate through the flexible substrate 110, as shown in fig. 9; alternatively, as shown in FIG. 3, the plurality of slots 1302 do not extend through the flexible substrate 110. When the flexible base 110 includes a first substrate 1101, a buffer layer 1103, and a second substrate 1102 that are sequentially stacked in a direction close to the display device 120, a plurality of grooves 1302 may penetrate the first substrate 1101, that is, as shown in fig. 4; also, the plurality of grooves 1302 may not extend through the first substrate 1101.

As will be understood by those skilled in the art, when the recess structure 130 includes a plurality of grooves 1302, the filler 1300 is filled in the plurality of grooves 1302, and the elastic modulus of the filler 1300 is smaller than that of the flexible substrate 110.

It will be appreciated by those skilled in the art that the greater the modulus of elasticity, the less deformable the material and the greater the stiffness, the greater the stiffness. That is, when the elastic modulus of the filler 1300 is large, the flexible substrate 110 can be ensured to have good supporting capability for the display device 120; the relatively low modulus of elasticity of filler 1300 may improve the bending properties of bend region a 1. The elastic modulus of the filler 1300 and the elastic modulus of the flexible substrate 110 can be set according to actual needs.

In some embodiments, the modulus of elasticity of the filler 1300 is T of the modulus of elasticity of the flexible substrate 110₂Multiple, wherein, T is more than or equal to 0.06₂Is less than 1. In this case, it is possible to ensure that the flexible substrate 110 has a good supporting capability for the display device 120, and to improve the bending performance of the bending region a 1.

On the basis, the elastic modulus of the filler 1300 can be set in a range of 1000MPA to 6000 MPA; the elastic modulus of the flexible substrate 110 ranges from 6000MPA to 15000 MPA.

For example, the filler 1300 may have an elastic modulus of 1000MPA, 2000MPA, 3000MPA, 4000MPA, 5000MPA, 6000MPA, or the like. The elastic modulus of the flexible substrate 110 may be 6000MPA, 7000MPA, 8000MPA, 9000MPA, 10000MPA, 11000MPA, 12000MPA, 13000MPA, 14000MPA, 15000MPA, or the like.

In some embodiments, the material of the filler 1300 is a photo-curable glue or a thermal-curable glue.

In this embodiment, the photo-curing adhesive or the thermosetting adhesive is completely cured by light or heat, and can be well filled in the recessed structure, thereby improving the reliability and stability of the display substrate 100. The material of the photo-curing adhesive or the thermal curing adhesive is not limited herein as long as the elastic modulus thereof is lower than that of the flexible substrate 110.

Illustratively, the material of the filler 1300 may be OCA glue (Optical Clear Adhesive) or UV glue (Ultraviolet curable Adhesive).

The OCA glue and the UV glue have certain light curing performance and lower elastic modulus, any one of the OCA glue and the UV glue is filled in the recessed structure 130 of the display substrate 100, the advantages of simple process are achieved, and the bending performance of the bending area of the display substrate 100 can be improved.

In some embodiments, as shown in fig. 8 and 9, the display substrate 100 further includes: a glue layer 140 and a backing film 150.

The glue layer 140 is located on a side of the flexible substrate 110 and the filler 1300, which is away from the display device 120 as a whole; the back film 150 is located on a side of the glue layer 140 away from the display device 120.

In this example, the flexible substrate 110 and the filler 1300 are disposed on a side away from the display device 120, so that the display substrate 100 is prevented from being damaged by external force during bending or folding, and reliability and product stability of the display substrate 100 are improved.

In some embodiments, as shown in fig. 8, the material of the glue layer 140 is the same as that of the filler 1300 in the recess structure 130, and the glue layer 140 and the filler 1300 are formed by a single patterning process without adding an additional Mask.

It should be noted that: the one-time patterning process refers to one-time photolithography process, which may include, for example, exposure, development, and etching processes.

In some embodiments, as shown in fig. 9, the material of the filler 1300 is an optical adhesive, and the material of the adhesive layer 140 is a pressure sensitive adhesive.

Hereinafter, simulation calculation is performed for three display substrates having different structures. The test results are shown in fig. 10A to 10C: fig. 10A is a stress cloud diagram of the substrate 110 being a uniform PI (Polyimide) layer, when the thickness of the PI layer is 20um, showing the corresponding positions of the package layer 121 after the substrate 100 is bent; fig. 10B is a stress cloud diagram corresponding to different positions of the encapsulation layer 121 after the display substrate 100 is bent when the thickness of the PI layer is 10um and the depth of the concave structure 130 is 10um in the bending region a1, where the surface of the bending region a1 of the flexible substrate 110 away from the display device 120 is provided with the concave structure 130;

fig. 10C is a stress cloud diagram corresponding to different positions of the encapsulation layer 121 after the display substrate 100 is bent when the flexible substrate 110 is provided with the concave structure 130 on the surface away from the display device 120, the concave structure 130 penetrates through the flexible substrate 110, and the depth of the concave structure 130 is 20 um.

As can be seen from fig. 10B, compared to the structure corresponding to fig. 10A, when the surface of the bending region a1 of the flexible substrate 110, which is far away from the display device 120, is provided with the recessed structure 130, and when the thickness of the PI layer is 10um and the depth of the recessed structure 130 is 10um in the bending region a1, the stress at each position of the encapsulation layer 121 corresponding to the bending region a1 is relatively reduced after the display substrate 100 is bent.

As can be seen from fig. 10C, compared to the structure corresponding to fig. 10A, when the concave structure 130 is disposed on the surface of the flexible substrate 110 away from the display device 120, the concave structure 130 penetrates through the flexible substrate 110, and the depth of the concave structure 130 is 20um, after the display substrate 100 is bent, the stress at most positions of the encapsulation layer 121 corresponding to the bending region a1 is relatively reduced.

Fig. 11 is a graph showing stress comparison between the package layer 121 and the three display substrates 100 at different positions after bending.

As shown in fig. 11, when the surface of the bending region a1 of the flexible substrate 110 away from the display device 120 is provided with the concave structure 130, the thickness of the PI layer is 10um, and the depth of the concave structure 130 is 10um, the stress of the package layer 121 corresponding to the middle of the bending region is a uniform PI (Polyimide) layer with respect to the substrate 110, and when the thickness of the PI layer is 20um, the stress of the encapsulation layer 121 corresponding to the middle of the bending region can be reduced by 40.5%, the surface of the bending region a1 of the flexible substrate 110 away from the display device 120 is provided with the concave structure 130, the concave structure 130 penetrates through the flexible substrate 110, when the depth of the concave structure 130 is 20um, the stress of the package layer 121 corresponding to the middle of the bending region is a uniform PI (Polyimide) layer relative to the substrate 110, and when the thickness of the PI layer is 20um, the stress of the package layer 121 corresponding to the middle of the bending region can be reduced by 24.1%.

In summary, in the display substrate 100 provided in some embodiments of the present disclosure, the recessed structure 130 is disposed on the surface of the flexible substrate 110 away from the display device 120, the recessed structure 130 is at least located in the bending region a1, and the filler 1300 is filled in the recessed structure 130, and the elastic modulus of the filler 1300 is smaller than the elastic modulus of the flexible substrate 110, so as to reduce the bending stress of the display substrate 100 in the bending region a1, improve the bending performance of the display substrate 100, and improve the problem that the device in the bending region is easily damaged; meanwhile, the neutral layer of the bending region a1 of the display substrate 100 can be moved upward, so that the metal traces and the package layer in the bending region a1 are closer to the neutral layer, the tensile stress of the metal traces and the package layer in the bending region a1 is reduced, the device in the bending region a1 is prevented from being damaged, and the problem that the device in the bending region a1 is easily damaged is solved.

An embodiment of the present disclosure provides a display panel 200, as shown in fig. 12. The display panel 200 includes the display substrate 100 provided in the above embodiments.

The beneficial effects that the display panel 200 provided in the present disclosure can achieve are the same as the beneficial effects that the display substrate 100 provided in the above technical solution can achieve, and are not described herein again.

In some embodiments, the display panel 200 further includes: the touch control display device comprises a touch control functional layer 203, a polarizing layer 204 and a protective cover plate 205 which are positioned on the display side of the display substrate 100 and are sequentially stacked along the direction away from the display substrate 100.

The touch functional layer 203 may be of various types, and may be set according to actual needs. In some examples, the touch function Layer 203 is of a type FMLOC (Flexible Multi-Layer On Cell, in which a Flexible multilayer structure is formed On the encapsulation Layer 3 of the display substrate 100), and in other examples, the touch function Layer 203 is of a type FSLOC (Flexible Single-Layer On Cell, in which a Flexible Single-Layer structure is formed On the encapsulation Layer 3 of the display substrate 100), which is not limited in this respect.

The polarizing layer 204 may be a conventional external polarizer or coe (color film on ncappcation, that is, a color film is directly formed on the top of the encapsulation layer), instead of an external polarizer, and the filter function is directly integrated on the display backplane, so that the thickness of the display backplane can be significantly reduced, and a large amount of production cost can be saved.

In some embodiments, the display panel 200 further includes: and an adhesive layer 202 and a support layer 201 which are positioned on the non-display side of the display substrate 110 and are sequentially stacked in a direction away from the display substrate 100.

The non-display side of the display substrate 110 is opposite to the display side of the display substrate 100.

Embodiments of the present disclosure also provide a display device 1000, as shown in fig. 13. The display device 1000 includes the display panel 200 provided in the above embodiment.

In some examples, display device 1000 may be any device that displays text or images, whether in motion (e.g., video) or stationary (e.g., still images). More particularly, it is contemplated that the embodiments may be implemented in or associated with a variety of electronic devices such as, but not limited to, mobile telephones, wireless devices, Personal Digital Assistants (PDAs), hand-held or portable computers, Global Positioning System (GPS) receivers/navigators, cameras, motion Picture Experts Group (MP 4) video players, video cameras, game consoles, wrist watches, clocks, calculators, television monitors, computer monitors, automobile displays (e.g., odometer display, etc.), navigators, cockpit controls and/or displays, displays of camera views (e.g., displays of rear view cameras in vehicles), electronic photographs, electronic billboards or signs, video game consoles, and the like, Projectors, architectural structures, packaging, and aesthetic structures (e.g., displays of images for a piece of jewelry), and the like.

For example, the display device 1000 may further include a frame, a source driver chip, an FPC (Flexible Printed Circuit), a PCB (Printed Circuit Board), other electronic components, and the like.

The beneficial effects that the display device 1000 provided in the present disclosure can achieve are the same as the beneficial effects that the display panel 200 provided in the above technical solution can achieve, and are not described herein again.

Referring to fig. 14, the present disclosure further provides a method for manufacturing the display substrate 100, which is used to manufacture the display substrate 100. The display substrate 100 has a bending region a1, and the method for manufacturing the display substrate 100 includes steps S1 to S3.

S1: a base substrate is provided.

The flexible substrate 110 may be formed as a single layer, a double layer, or multiple layers, and specific reference may be made to the description in some embodiments above, which is not described herein again.

S2: the display device 120 is formed on the flexible substrate 110, and the surface of the flexible substrate 110 far away from the display device 120 is provided with the concave structure 130, and the concave structure 130 is at least located in the bending region a 1.

The specific arrangement of the recess structure 130 can refer to the foregoing embodiments, and is not described herein again.

S3: the filling material 1300 is filled in the recess structure 130, and the elastic modulus of the filling material 1300 is smaller than that of the flexible substrate 110.

The display substrate 100 provided by some embodiments of the present disclosure may be used to prepare the display substrate 100 in any of the above embodiments, where the display substrate 100 is configured with the recessed structure 130 on the surface of the flexible substrate 110 away from the display device 120, the recessed structure 130 is at least located in the bending region a1, and the filler 1300 is filled in the recessed structure 130, and the elastic modulus of the filler 1300 is smaller than the elastic modulus of the flexible substrate 110, so as to reduce the bending stress of the display substrate 100 in the bending region a1, improve the bending performance of the display substrate 100, and improve the problem that the device in the bending region is easily damaged; meanwhile, the neutral layer of the bending region a1 of the display substrate 100 can be moved upward, so that the metal traces and the package layer in the bending region a1 are closer to the neutral layer, the tensile stress of the metal traces and the package layer in the bending region a1 is reduced, the device in the bending region a1 is prevented from being damaged, and the problem that the device in the bending region a1 is easily damaged is solved.

In addition, in step S3, the filling material 1300 is filled into the recessed structure 130: after the flexible substrate 110 and the display device 120 are formed, the recess structure 130 is disposed on the surface of the flexible substrate 110 away from the display device 120, and the filling material 1300 is filled in the recess structure 130; alternatively, the flexible substrate 110 may be formed after the filler 1300 is formed, and the recess structure 130 is directly formed on the flexible substrate 110 due to the influence of the filler, that is, the filler 1300 is directly embedded into the recess structure 130 when the flexible substrate 110 is formed. The following describes the manufacturing method in some embodiments with reference to fig. 15, 16A to 16C, and 17, 18A to 18C.

In some embodiments, referring to fig. 15, a method for preparing the display substrate 100 includes:

s10: forming a display device 120 on the flexible substrate 110;

in this step, as shown in fig. 16A. The display device 120 may include a display function layer 121 and an encapsulation layer 122, and the display function layer 121 and the encapsulation layer 122 may be sequentially formed on the flexible substrate 110.

S20: after the flexible substrate 110 is peeled off from the display device, the recess structure 130 is formed on the surface of the flexible substrate 110 away from the display device 120, and the filling material 1300 is filled in the recess structure 130.

In some examples, the flexible substrate 110 may be peeled off from the display device as a whole by sintering the bottom surface of the carrier substrate 001 with a laser to peel off the flexible substrate 110 and the display device 120 as a whole from the carrier panel 001.

In this step, as shown in fig. 16B to 16C, the recess structure 130 includes at least one hole 1301 and/or at least one groove 1302. Specifically, the recess structure 130 may be formed by etching.

When the flexible substrate 110 is a single-layer structure, the hole 1301 or the groove 1302 may penetrate through the flexible substrate 110, as shown in fig. 9; alternatively, as shown in FIG. 3, the hole 1301 or the slot 1302 does not extend through the flexible substrate 110. When the flexible base 110 includes a first substrate 1101, a buffer layer 1103, and a second substrate 1102 sequentially stacked in a direction close to the display device 120, a hole 1301 or a groove 1302 may penetrate the first substrate 1101, that is, as shown in fig. 4; also, the hole 1301 or the groove 1302 may not penetrate the first substrate 1101.

Note that, in step S20, the concave structure 130 may be formed at least at a position in the surface of the flexible substrate 110 away from the display device 120, where the position is located in the bending region. Here, "forming the recess structure 130 at least at a position located at the bending region in the surface of the flexible substrate 110 away from the display device 120" includes: the concave structure 130 is formed at a position of the bending region in the surface of the flexible substrate 110 far from the display device 120, and the concave structure 130 is formed at a position of at least a part of the non-bending region in the surface of the flexible substrate 110 far from the display device 120, in addition to the concave structure 130 formed at a position of the bending region in the surface of the flexible substrate 110 far from the display device 120.

In some examples, the entire area of the display substrate 100 is the bending region a1, and the concave structure 130 is formed on the surface of the flexible substrate 110 away from the display device 120 in the bending region, in particular referring to fig. 1, at this time, the display substrate 100 may be used to form a roll-to-roll display product.

In other examples, referring to fig. 2, the display substrate 100 further has at least one non-bending region a2 adjacent to the bending region a 1. At this time, the recessed structure 130 may be located entirely in the bending region a1, or may be located in a part of the non-bending region a2 in addition to the bending region a 1.

For example, as shown in fig. 2, the display substrate 100 has two non-bending regions a2, and the first non-bending region a21 and the second non-bending region a22 are respectively located at two opposite sides of the bending region a1, and at this time, the display substrate 100 may be used to form a folded display product.

The manufacturing method provided by some embodiments of the present disclosure is used for manufacturing the display substrate 100, and because the concave structure 130 is disposed on the surface of the flexible substrate 110 away from the display device 120, the concave structure 130 is at least located in the bending region a1, and the elastic modulus of the filler 1300 in the concave structure 130 is smaller than the elastic modulus of the flexible substrate 110, the bending stress of the display substrate 100 in the bending region a1 can be reduced, the bending performance of the display substrate 100 can be improved, and the neutral layer of the display substrate 100 can be moved upwards, so that the metal traces and the encapsulation layer in the bending region a1 are closer to the neutral layer, the tensile stress of the metal traces and the encapsulation layer in the bending region a1 is reduced, the device in the bending region a1 is prevented from being damaged, and the problem that the device in the bending region a1 is easily damaged is improved.

In other embodiments, referring to fig. 17, a method for manufacturing the display substrate 100 includes steps S100 to S400.

S100: a filler 1300 is formed on the carrier panel 001.

In this step, as shown in fig. 18A. The material of the filler 1300 may be a photo-curing adhesive or a thermosetting adhesive, which may specifically refer to the descriptions in some embodiments above and will not be described herein again.

S200: a flexible substrate 110 is formed on the carrier panel 001, a concave structure 130 is formed on the flexible substrate 110, and a filler 1300 is embedded in the concave structure 130.

In this step, as shown in fig. 18B, the filler 1300 is a one-piece structure, and the recess structure 130 is a structure corresponding to the filler 1300. After the flexible substrate 110 is formed, the filler 1300 may be directly embedded into the recess structure 130.

In some examples, the recessed feature 130 may include at least one hole 1301 and/or at least one groove 1302, as described with particular reference to fig. 3-6 and 8-9. When the recess structure 130 includes at least one hole 1301 and/or at least one groove 1302, before this step, patterning the low-modulus filler 1300 to a structure corresponding to the recess structure 130 by exposure development or etching is further included.

S300: the display device 120 is formed on a side of the filler 1300 and the flexible substrate 110 integrally remote from the carrier panel.

In this step, as shown in fig. 18C. Illustratively, the display device 120 may include a display function layer 121 and an encapsulation layer 122, as can be seen in fig. 8 and 9.

S400: the filler 1300, the flexible substrate 110, and the display device 120 are entirely peeled off from the carrier panel 001 to form the display substrate 100.

In this step, the bottom surface of the carrier substrate 001 may be sintered using a laser to peel the filler, the flexible substrate 110, and the display device 120 as a whole from the carrier panel 001. Specifically, the method comprises the following steps: the first area A3 in the carrier panel 001 in contact with the filler is irradiated with a first energy laser, and the second area a4 in the carrier panel 001 in contact with the flexible substrate 110 is irradiated with a second energy laser.

Wherein the energy density of the second energy laser is greater than the energy density of the first energy laser.

In another embodiment of the present disclosure, a manufacturing method is used for manufacturing the display substrate 100, on one hand, because the concave structure 130 is disposed on the surface of the flexible substrate 110 away from the display device 120, the concave structure 130 is at least located in the bending region a1, and the elastic modulus of the filler 1300 in the concave structure 130 is smaller than the elastic modulus of the flexible substrate 110, the bending stress of the display substrate 100 in the bending region a1 can be reduced, the bending performance of the display substrate 100 can be improved, and the neutral layer of the display substrate 100 can be moved upwards, so that the metal traces and the encapsulation layer in the bending region a1 are closer to the neutral layer, the tensile stress of the metal traces and the encapsulation layer in the bending region a1 is reduced, the device in the bending region a1 is prevented from being damaged, and the problem that the device in the bending region a1 is easily damaged is improved; on the other hand, the filler 1300 and the flexible substrate 110 are formed first, and then the display device 120 is formed, so that the problem that the performance of the display device 120 is affected by damage to the display device 120 caused by the filler and the flexible substrate 110 during the high-temperature curing process can be solved, and the recess structure 130 can be formed without adding an additional Mask (Mask), and the method has the advantages of simple process, convenience in manufacturing and low cost.

The above description is only an embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions within the technical scope of the present disclosure should be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A display substrate having a bend region, the display substrate comprising:

a flexible substrate;

a display device disposed on the flexible substrate; a concave structure is arranged on the surface of the flexible substrate far away from the display device, and the concave structure is at least positioned in the bending area; and the number of the first and second groups,

and the filler is filled in the concave structure, and the elastic modulus of the filler is smaller than that of the flexible substrate.

2. The display substrate of claim 1, wherein the display substrate further has at least one non-bending region adjacent to the bending region;

the concave structure is also positioned in the non-bending area and is close to the bending area.

3. The display substrate according to claim 2, wherein a direction from the bending region to the non-bending region is a first direction;

the size of the area of the non-bending area close to the bending area in the first direction is less than or equal to 0.2 times of the size of the bending area in the first direction.

4. The display substrate according to any one of claims 1 to 3,

the recessed structure extends through the flexible substrate.

5. The display substrate according to any one of claims 1 to 3,

the depth of the concave structure is T of the thickness of the flexible substrate₁Multiple, wherein, T is more than or equal to 0.25₁＜1。

6. The display substrate according to any one of claims 1 to 3,

the flexible substrate includes a plurality of layers of substrates sequentially stacked in a direction close to the display device; the recessed structure penetrates through at least one layer of substrate, and the elastic modulus of the at least one layer of substrate is smaller than that of the substrate which is not penetrated in the multilayer substrate.

7. The display substrate of claim 6,

the number of the substrates is two, and the flexible substrate further comprises a buffer layer positioned between the two substrates; the concave structure penetrates through the substrate, far away from the display device, of the two layers of substrates.

8. The display substrate according to any one of claims 1 to 3,

the recessed feature comprises at least one hole and/or at least one groove;

wherein the cross section of at least one hole is in any one of a rectangular shape, a semicircular shape, a semi-elliptical shape, a trapezoidal shape and a triangular shape, and the cross section is a section parallel to the axial direction of the hole; and/or the cross section of at least one groove is in the shape of any one of rectangle, semicircle, semi-ellipse, trapezoid and triangle, and the cross section is a section perpendicular to the extending direction of the groove.

9. The display substrate according to any one of claims 1 to 3,

the recessed structure comprises a plurality of holes which are uniformly distributed.

10. The display substrate according to any one of claims 1 to 3,

the recessed structure comprises a plurality of grooves which are sequentially arranged along a first direction, and the plurality of grooves extend along a second direction which is crossed with the first direction.

11. The display substrate according to any one of claims 1 to 3,

the elastic modulus of the filler is T of the elastic modulus of the flexible substrate₂Multiple, wherein, T is more than or equal to 0.06₂＜1。

12. The display substrate according to any one of claims 1 to 3,

the filler is made of light curing glue or heat curing glue.

13. The display substrate according to any one of claims 1 to 3, further comprising,

the glue layer is positioned on one side, away from the display device, of the flexible substrate and the filler; and the combination of (a) and (b),

the back film is positioned on one side of the adhesive layer, which is far away from the display device;

the glue layer and the filler are made of the same material and are formed through a one-time composition process; or the filler is made of optical adhesive, and the adhesive layer is made of pressure-sensitive adhesive.

14. A display panel, comprising:

a display substrate according to any one of claims 1 to 13.

15. The manufacturing method of the display substrate is characterized in that the display substrate is provided with a bending area; the manufacturing method comprises the following steps:

providing a flexible substrate;

forming a display device on a flexible substrate; a concave structure is arranged on the surface of the flexible substrate far away from the display device, and the concave structure is at least positioned in the bending area; and the number of the first and second groups,

and filling filler in the recessed structure, wherein the elastic modulus of the filler is smaller than that of the flexible substrate.