Display panel and preparation method thereof

Abstract

The present disclosure provides a display panel and a manufacturing method thereof. The display panel comprises a display area and a bending area located at least one side of the display area. The display panel further comprises a substrate, a conductive layer and a protective layer located on the substrate. At least part of the conductive layer and the protective layer are located in the bending area, and the conductive layer is located between the protective layer and the substrate. The thickness of the part of the substrate located in the bending area is smaller than the thickness of the part of the substrate located in the display area. In the bending area, the thickness of the protective layer is designed such that the stress neutral layer of the bending area is located in the conductive layer. The above design is conducive to reducing the bending radius of the bending area, thereby facilitating the design of an extremely narrow frame of the display panel and the miniaturization design of the display panel.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and more specifically, to a display panel and a method for manufacturing the same. Background Technology

[0002] With the widespread use of electronic display products in people's daily lives, users have increasingly higher demands for the appearance of electronic display products, especially the screen ratio. Under this demand, electronic display products with full-screen display functions under the concepts of narrow bezels and bezel-less displays have emerged.

[0003] In electronic display products, the bezel area of ​​the display panel can be bent to the back, thus creating a visually narrow or borderless effect. However, due to the structural design limitations of current electronic display products, bending the display panel can easily result in damage, and it is difficult to further reduce the bending radius. Summary of the Invention

[0004] This disclosure provides a display panel including a display area and a bent region located on at least one side of the display area. The display panel also includes a substrate and a conductive layer and a protective layer located on the substrate. At least a portion of the conductive layer and the protective layer are located in the bent region, with the conductive layer positioned between the protective layer and the substrate. The thickness of the portion of the substrate located in the bent region is less than the thickness of the portion of the substrate located in the display area, and in the bent region, the thickness of the protective layer is designed such that a stress-neutral layer in the bent region is located within the conductive layer.

[0005] In the above solution, thinning the substrate in the bending area can reduce the stress generated during bending. In addition, to ensure that the stress neutral layer in the bending area is located in the conductive layer during bending to avoid breakage of the conductive layer, the design thickness of the protective layer is also reduced, thereby further reducing the bending stress of the protective layer. Thus, the bending stress generated in the bending area of ​​the display panel can be reduced, which is beneficial to reducing the bending radius of the bending area and thus facilitating the design of ultra-narrow bezels for the display panel. Furthermore, as the bending radius of the bending area decreases, the design width of the bending area also decreases, thereby reducing the overall design size of the display panel without affecting the size of the display area, which is beneficial to the miniaturization design of the display panel.

[0006] In one specific embodiment of the first aspect of this disclosure, the display panel may further include a bonding area, a bending area located between the bonding area and the display area, and a conductive layer including a plurality of signal lines extending from the display area to the bonding area.

[0007] In one specific embodiment of the first aspect of this disclosure, a groove is provided on the side of the substrate away from the protective layer in the bending region.

[0008] For example, alternatively, the groove can be formed by laser ablation, resulting in multiple protrusions at the bottom of the groove. This method increases the surface area at the bottom of the groove, thereby increasing the stress relief area in the bending zone and reducing the risk of stress concentration when the display panel is bent.

[0009] For example, optionally, under the action of laser ablation, the distance between the tips of adjacent protrusions can be approximately 5 to 20 micrometers, and / or the height of the protrusions can be approximately 1 to 10 micrometers.

[0010] In one specific embodiment of the first aspect of this disclosure, the substrate includes a first substrate and a second substrate stacked sequentially, the second substrate being located between the first substrate and the conductive layer, and a groove being located in the first substrate.

[0011] For example, the bottom of the groove may be located in the first substrate, or extend into the second substrate, or be located at the junction of the first and second substrates.

[0012] For example, the substrate may optionally include a spacer layer located between the first substrate and the second substrate, the density of which is greater than that of the first substrate.

[0013] For example, optionally, the first substrate is an organic layer and the spacer layer is an inorganic layer.

[0014] In another specific embodiment of the first aspect of this disclosure, the substrate includes a first substrate and a second substrate stacked sequentially, the second substrate being located between the first substrate and the conductive layer, a groove being located in the first substrate, and the first substrate having a greater absorption rate of light in a first wavelength range than the second substrate having a greater absorption rate of light in the first wavelength range.

[0015] In the above scheme, when the first substrate is irradiated with light in the first wavelength range, the first substrate can absorb more light and thus detach from the second substrate. In this way, after cutting the part of the first substrate located in the bending area, the part will fall off directly without remaining on the second substrate. In addition, this method generates less heat, which can avoid adverse effects on the components in the display panel, such as the driving circuit.

[0016] For example, optionally, the bottom of the groove is located on the surface of the second substrate.

[0017] For example, optionally, the light in the first wavelength range is laser light.

[0018] For example, optionally, the material of the first substrate includes the conjugated polymer polyaramid, and the material of the second substrate includes polyimide.

[0019] In another specific embodiment of the first aspect of this disclosure, a groove is provided on the side of the substrate facing the protective layer in the bending region.

[0020] For example, optionally, the substrate includes a first substrate and a second substrate stacked in sequence, the portion of the first substrate located in the bending region is provided with an opening, the portion of the second substrate located in the bending region fills the opening and conforms to the opening to form a groove, and a conductive layer and a protective layer fill the groove.

[0021] In the above solution, the substrate in the bending area can be thinned before other film layers, such as conductive layers, are formed on the substrate, without adversely affecting the performance of the display panel.

[0022] In one specific embodiment of the first aspect of this disclosure, the display panel may further include a display functional layer located on a substrate and in a display area, the display functional layer including a pixel defining layer and a plurality of light-emitting devices defined by the pixel defining layer.

[0023] For example, optionally, at least a portion of the protective layer is in the same layer and made of the same material as the pixel defining layer.

[0024] For example, the display panel may optionally include an encapsulation layer covering the display function layer, the encapsulation layer including an organic encapsulation layer, and at least a portion of the protective layer being in the same layer and of the same material as the organic encapsulation layer.

[0025] In the above scheme, a protective layer can be prepared simultaneously during the preparation of the pixel defining layer and / or organic encapsulation layer, thereby reducing the manufacturing process of the display panel and lowering costs.

[0026] A second aspect of this disclosure provides a method for manufacturing a display panel, the method comprising: providing a carrier substrate and forming a substrate on the carrier substrate, wherein the substrate is divided into a display area and a bending area; thinning a portion of the substrate located in the bending area such that the thickness of the portion of the substrate located in the bending area is less than the thickness of the portion of the substrate located in the display area; depositing a conductive material on the substrate to form a conductive layer, at least a portion of the conductive layer being formed in the bending area; forming a protective layer on a side of the conductive layer opposite to the substrate, at least a portion of the protective layer being formed in the bending area and covering the conductive layer, wherein the protective layer is formed to have a thickness such that a stress-neutral layer in the bending area is located in the conductive layer; and removing the carrier substrate.

[0027] In one specific embodiment of the second aspect of this disclosure, the step of thinning the portion of the substrate located in the bending region such that the thickness of the portion of the substrate located in the bending region is less than the thickness of the portion of the substrate located in the display region may include: after removing the carrier substrate, laser ablation of the substrate in the bending region from the side of the substrate away from the protective layer to form a groove on the side of the substrate away from the protective layer.

[0028] For example, alternatively, the bottom of the groove may have multiple protrusions.

[0029] For example, optionally, the step of thinning the portion of the substrate located in the bending region so that the thickness of the portion of the substrate located in the bending region is less than the thickness of the portion of the substrate located in the display region may include: sequentially forming a first substrate, a spacer layer and a second substrate on a carrier substrate; in the bending region, laser ablation of the substrate from the side of the first substrate opposite to the second substrate, and at least removing the portion of the first substrate located in the bending region so that the bottom of the groove is a plane.

[0030] For example, alternatively, the groove is formed in the first substrate, or the groove is formed to extend into the second substrate, or the groove is formed to extend into the boundary region of the first substrate and the second substrate.

[0031] For example, optionally, the first substrate is an organic layer and the spacer layer is an inorganic layer.

[0032] In another specific embodiment of the second aspect of this disclosure, the step of thinning the portion of the substrate located in the bending region such that the thickness of the portion of the substrate located in the bending region is less than the thickness of the portion of the substrate located in the display region may include: forming a first film layer on a carrier substrate; etching the first film layer to remove the portion of the first film layer located in the bending region to form an opening; the remaining portion of the first film layer forming a first substrate; forming a second substrate on the side of the first film layer opposite to the carrier substrate, wherein the portion of the second substrate located in the bending region fills the opening and conforms to the opening to form a groove, and the first substrate and the second substrate constitute a substrate.

[0033] In another specific embodiment of the second aspect of this disclosure, the step of thinning the portion of the substrate located in the bending region such that the thickness of the portion of the substrate located in the bending region is less than the thickness of the portion of the substrate located in the display region may include: sequentially depositing a first film layer and a second film layer on a carrier substrate, the first film layer being formed between the carrier substrate and the second film layer, wherein the absorption rate of the first film layer for light in a first wavelength range is greater than the absorption rate of the second film layer for light in the first wavelength range; after removing the carrier substrate, laser ablation of the first film layer from the side of the first film layer opposite to the second film layer in the bending region, and removing the portion of the first film layer located in the bending region to form a groove, wherein the remaining portion of the first film layer forms a first substrate, the second film layer forms a second substrate, and the first substrate and the second substrate constitute a substrate.

[0034] For example, alternatively, the bottom of the groove may have multiple protrusions. Attached Figure Description

[0035] Figure 1 This disclosure provides a schematic diagram of the planar structure of a display panel according to an embodiment.

[0036] Figure 2 for Figure 1The diagram shows a cross-sectional view of the display panel in its flattened state.

[0037] Figure 3 for Figure 2 The diagram shows a cross-sectional view of the display panel in a bent state.

[0038] Figure 4 This is an enlarged view of the bent area of ​​a display panel provided in an embodiment of this disclosure.

[0039] Figure 5 An enlarged view of the bending area of ​​another display panel provided in an embodiment of this disclosure.

[0040] Figure 6 An enlarged view of the bending area of ​​another display panel provided in an embodiment of this disclosure.

[0041] Figure 7 This is a cross-sectional view of another display panel provided in a flattened state according to an embodiment of the present disclosure.

[0042] Figure 8 for Figure 7 The diagram shows a cross-sectional view of the display panel in a bent state.

[0043] Figure 9 An enlarged view of the bending area of ​​another display panel provided in an embodiment of this disclosure.

[0044] Figure 10 This is a cross-sectional view of a portion of the display area of ​​a display panel provided in an embodiment of the present disclosure.

[0045] Figure 11 This is a cross-sectional view of a display panel in a bent state, according to an embodiment of the present disclosure.

[0046] Figure 12 This is a flowchart illustrating a method for manufacturing a display panel according to an embodiment of the present disclosure.

[0047] Figures 13A to 13C This is a process diagram illustrating a method for fabricating a substrate for a display panel according to an embodiment of this disclosure.

[0048] Figures 14A to 14D This is a process diagram illustrating a method for fabricating a substrate for a display panel according to an embodiment of this disclosure.

[0049] Figures 15A to 15C This is a process diagram illustrating a method for fabricating a substrate for a display panel according to an embodiment of this disclosure. Detailed Implementation

[0050] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this specification.

[0051] Due to the need for extremely narrow bezels, certain areas of the display panel (such as the bonding area, also known as the solder pad area) are bent to the back, thereby reducing the width of the non-display area of ​​the display device, i.e., reducing the bezel width. To meet the requirement of bendability, the display panel needs to be a flexible panel (flexible overall or only the bending area is designed to be flexible). In this case, the thickness of the bending area of ​​the display panel directly affects the stress generated during bending. If the stress during bending is too high, it can cause damage to the bending area of ​​the display panel, such as trace breakage, resulting in poor signal. In addition, due to the limitation of bending stress, the bending area of ​​the display panel needs to be set with a larger width to provide a sufficient bending radius, which obviously also means that the design size of the display panel cannot be further reduced.

[0052] This disclosure provides at least one embodiment of a display panel and a method for manufacturing the same, to at least solve the aforementioned technical problems. The display panel includes a display area and a bending area located on at least one side of the display area. The display panel also includes a substrate and a conductive layer and a protective layer located on the substrate. At least a portion of the conductive layer and the protective layer is located in the bending area, with the conductive layer positioned between the protective layer and the substrate. The thickness of the portion of the substrate located in the bending area is less than the thickness of the portion of the substrate located in the display area, and in the bending area, the thickness of the protective layer is designed such that a stress-neutral layer in the bending area is located within the conductive layer. In this design, thinning the substrate in the bending area reduces the stress generated during bending. Furthermore, to ensure the stress neutral layer in the bending area is located within the conductive layer during bending to prevent breakage, the protective layer's design thickness is also reduced, further lowering the bending stress on the protective layer. This reduces the bending stress in the display panel's bending area, facilitating a smaller bending radius and enabling ultra-narrow bezel designs. Additionally, as the bending radius decreases, the design width of the bending area also decreases, allowing for a smaller overall display panel size without affecting the display area dimensions, thus promoting miniaturization.

[0053] The following description, in conjunction with the accompanying drawings, illustrates a display panel and its fabrication method according to at least one embodiment of the present disclosure. Furthermore, in these drawings, a spatial rectangular coordinate system is established with reference to the substrate to illustrate the positional relationships of the various structures within the display substrate. In this spatial rectangular coordinate system, the X-axis and Y-axis are parallel to the surface of the substrate, with the X-axis parallel to the direction from the display area to the bending area, and the Z-axis perpendicular to the surface of the substrate.

[0054] like Figures 1 to 4 As shown, the planar area of ​​the display panel 10 includes a display area 11 and a bending area 12, with the bending area 12 located on at least one side of the display area 11. The solid structure of the display panel 10 includes a substrate 100 and a conductive layer 200 and a protective layer 300 located on the substrate 100. At least a portion of the conductive layer 200 and the protective layer 300 are located in the bending area 12, and the conductive layer 200 is located between the protective layer 300 and the substrate 100.

[0055] For example, the planar area of ​​the display panel 10 may also include a bonding area 13, and a bending area 12 is located between the display area 11 and the bonding area 13 to connect the display area 11 and the bonding area 13. The bonding area 13 may be provided with bonding terminals for bonding chips and / or bonding with external circuits (e.g., flexible circuit boards). For example, the conductive layer 200 includes multiple signal lines extending from the display area 11 to the bonding area 13, so that the circuit structure of the display area 11 (e.g., the pixel driving circuit described below) can be connected to the bonding terminals of the bonding area 13 to control the display function of the display panel 10. In practical applications, the bending area 12 will be bent (e.g., along...). Figure 2 (in the direction of the arrow in the image), thereby causing the bonding area 13 to bend to the back of the display area 11 to narrow the bezel of the display panel 10.

[0056] When the display panel 10 is bent, the bonding area 13 is located on the back of the display area 11 (the side opposite to the light-emitting side). When the display panel 10 is flat, the bonding area 13 is located on the side of the bent area 12 away from the display area 11.

[0057] In embodiments of this disclosure, after bending the display panel, the stress-neutral layer at the bending region 12 needs to be located within the conductive layer 200 to prevent the conductive layer 200 from breaking after bending. Because the thickness of the substrate 100 is reduced in the bending region 12, the thickness of the protective layer 300 also needs to be adjusted to prevent the stress-neutral layer from shifting out of the conductive layer 200. That is, the thickness of the portion of the substrate 100 located in the bending region 12 is less than the thickness of the portion of the substrate 100 located in the display region 11, and in the bending region 12, the thickness of the protective layer 300 is designed such that the stress-neutral layer is located within the conductive layer 200.

[0058] For example, in the bending region 12, if the strength (e.g., elastic modulus) of the material of the protective layer 300 is approximately equal to the strength of the material of the substrate 100, then the thicknesses of the protective layer 300 and the substrate 100 can be designed to be approximately equal; if the strength of the material of the protective layer 300 is greater than the strength of the material of the substrate 100, then the thickness of the protective layer 300 needs to be less than the thickness of the substrate 100; if the strength of the material of the protective layer 300 is less than the strength of the material of the substrate 100, then the thickness of the protective layer 300 needs to be greater than the thickness of the substrate 100.

[0059] It should be noted that the "stress-neutral layer" is a virtual layer, which is the boundary between tensile stress and compressive stress under stress (bending state in this disclosure). At this boundary, the target object is neither under tension nor under compression.

[0060] In the embodiments of this disclosure, the method of thinning the portion of the substrate located in the bending region is not limited, and can be selected according to the specific structural design of the substrate and the actual process requirements. Below, several methods for thinning the portion of the substrate located in the bending region will be described through different embodiments.

[0061] In some embodiments of this disclosure, such as Figure 2 As shown, in the bending area 12, the substrate 100 can be grooved to achieve thinning, that is, a groove 101 is provided on the side of the substrate 100 away from the protective layer 300.

[0062] In some embodiments disclosed herein, a photolithography process can be performed on the substrate 100 from the back of the display panel to form a groove 101 on the substrate 100.

[0063] In other embodiments of this disclosure, the substrate 100 may be processed by ablation (e.g., laser ablation) to form the groove 101.

[0064] In the embodiments of this disclosure, the substrate can be configured as an integral structure, and the degree of thinning (groove depth) can be controlled by controlling parameters such as etching or ablation time. Alternatively, the substrate can be configured as multiple film layers, and the groove depth can be precisely controlled by etching specific film layers.

[0065] For example, in some embodiments of this disclosure, such as Figure 4 As shown, substrate 100 is an integrated structure. "Integrated structure" means that there are no two independent film layers in the target object, and there is no physical interface defining the different film layers.

[0066] For example, in other embodiments of this disclosure, such as Figure 5As shown, the substrate 100 includes a first substrate 110 and a second substrate 120 stacked sequentially. The second substrate 120 is located between the first substrate 110 and the conductive layer 200, and the groove 101 is located in the first substrate 110. For example, by controlling the material difference between the first substrate 110 and the second substrate 120, the groove 101 can be formed only in the first substrate 110. For example, the corrosion resistance of the second substrate 120 can be greater than that of the first substrate 110, or the first substrate 110 can be made of a material with high light absorption, so that the first substrate 110 is easily ablated by laser.

[0067] In at least one embodiment of this disclosure, such as Figure 4 and Figure 5 As shown, by employing methods such as laser ablation, the portion of the substrate 100 located at the bottom of the groove 101 can be etched unevenly, resulting in multiple protrusions 102 at the bottom of the groove 101 microscopically. These protrusions 102 can increase the surface area of ​​the bottom of the groove 101, thereby increasing the stress relief area of ​​the bending region 12 when the display panel is bent, thus reducing the risk of stress concentration.

[0068] For example, in the case of laser ablation, the distance between the tops of adjacent protrusions 102 is approximately 5 to 20 micrometers, and the height (or thickness) of the protrusions 102 is approximately 1 to 10 micrometers.

[0069] For example, along the direction perpendicular to the plane of the base (when the base is flat), the cross-sectional shape of the surface of the protrusion 102 can be an arc, a parabola, a "V" shape, etc.

[0070] It should be noted that, as described in the foregoing embodiments, regardless of whether the substrate is designed as an integrated structure or as including multiple film layers (e.g., first and second substrates), laser ablation can be performed to form grooves. The depth of the grooves can be designed according to the actual process requirements. Therefore, in the embodiments of this disclosure, there is no limitation on the extent to which the bottom of the groove and the protrusion formed on the bottom extend in the substrate.

[0071] For example, in some embodiments of this disclosure, when the substrate is an integral structure, the depth of the groove can be 1 / 4 to 3 / 4 of the thickness of the substrate before thinning (the thickness in the display area).

[0072] For example, in other embodiments of this disclosure, when the substrate includes multiple film layers such as a first substrate, a second substrate, and a spacer layer, the bottom of the groove may be located in the first substrate, or may extend into the second substrate, or may be located in the spacer layer at the junction of the first substrate and the second substrate.

[0073] In other embodiments of this disclosure, such as Figure 6As shown, the substrate 100 may further include a spacer layer 130 located between the first substrate 110 and the second substrate 120, the density of the spacer layer 130 being greater than the density of the first substrate 110. Thus, during etching, the high density of the spacer layer 130 can mitigate the etching rate, preventing rapid etching to the second substrate 120 and over-etching of the substrate 100. Furthermore, during ablation, the spacer layer 130 is relatively more resistant to ablation, preventing the second substrate 120 from being over-absorbed and detached, allowing the ablated portion of the first substrate 110 to detach and form a groove 101. This method allows the bottom of the groove 101 to be relatively flat (i.e., the size of the protrusion is relatively small) and facilitates control over the depth of the groove 101, reducing the risk of damage to the second substrate 120 during the process of forming the groove 101.

[0074] It should be noted that when the spacer layer 130 is provided, the bottom of the ablated groove 101 can be located in any one of the first substrate 110, the second substrate 120 and the spacer layer 130. In the case where the bottom of the groove 101 is formed in the first substrate 110, the bottom of the ablated groove 101 is located in the second substrate 120 or the spacer layer 130. Due to the aforementioned effect of the spacer layer 130, the size of the ablated protrusion is relatively smaller.

[0075] For example, optionally, the first substrate 110 is an organic layer and the spacer layer 130 is an inorganic layer. Compared to the organic layer, the inorganic layer has relatively higher density and is more resistant to ablation.

[0076] See again for at least one embodiment of this disclosure. Figure 5 The substrate 100 includes a first substrate 110 and a second substrate 120 stacked sequentially. The second substrate 120 is located between the first substrate 110 and the conductive layer 200. A groove 101 is located in the first substrate 110, and the absorption rate of the first substrate 110 for light in a first wavelength range is greater than that of the second substrate 120 for light in the first wavelength range. Thus, when the first substrate 110 is irradiated with light in the first wavelength range, the first substrate 110 can absorb more light and detach from the second substrate 120. Therefore, after cutting the portion of the first substrate 110 located in the bending region 12, this portion will directly detach without remaining on the second substrate 120. In addition, this method generates less heat, which can avoid adverse effects on devices in the display panel, such as driving circuits.

[0077] For example, optionally, if the first substrate 110 and the second substrate 120 are designed to have different absorption rates for light in the first wavelength range, the bottom of the groove 101 can be designed to have multiple protrusions to increase the stress relief capability of the substrate 100 when bent. For example, when the first substrate 110 is ablated by the aforementioned light, the surface of the second substrate 120 can be partially ablated to create protrusions at the bottom of the groove 101.

[0078] For example, optionally, the light in the first wavelength range is a laser. For instance, the laser can be generated by a carbon dioxide laser, which produces laser light by discharging carbon dioxide gas, and its wavelength can be around 10.6 micrometers; or, the laser can be emitted by a laser diode, and its wavelength can be in the visible light range or near-infrared range, for example, wavelengths of 808 nm, 980 nm, or 1064 nm; or, the laser can be generated by a yttrium neodymium oxide laser, and its wavelength can be 1064 nm; or, the laser can be generated by a rubidium vapor laser, and its wavelength can be 780 nm. It should be noted that in the embodiments of this disclosure, as long as the laser can be used to ablate the substrate, the method and type of laser generation can be selected according to the actual process requirements and are not limited herein.

[0079] For example, the material of the first substrate 110 may include the conjugated polymer polyaramid (CPI), and the material of the second substrate 120 may include polyimide (PI).

[0080] In other embodiments of this disclosure, such as Figures 7 to 9 As shown, thinning can be performed on the front side of the substrate 100, that is, a groove 101 is provided on the side of the substrate 100 facing the protective layer 300 in the bending area 12. For example, in some processes, the display panel is fabricated on a carrier substrate, and after the fabrication of the display panel is completed, the carrier substrate is peeled off. However, in the above solution, the groove 101 is located on the front side of the substrate 100, and the groove 101 can be fabricated simultaneously during the fabrication of the substrate 100, without the need to peel off the carrier substrate in advance, thereby reducing the difficulty of the display panel fabrication process.

[0081] For example, in at least one embodiment of this disclosure, such as Figures 7 to 9As shown, the substrate 100 includes a first substrate 110 and a second substrate 120 stacked sequentially. The portion of the first substrate 110 located in the bending region 12 has an opening. The portion of the second substrate 120 located in the bending region 12 fills the opening and conforms to it to form a groove 101. A conductive layer 200 and a protective layer 300 fill the groove 101. Thus, the substrate 100 in the bending region 12 can be thinned before other films, such as the conductive layer 200, are formed on the substrate 100, without adversely affecting the performance of the display panel. For example, when fabricating the substrate 100 on a carrier substrate, the opening in the bending region 12 can be formed first in the first substrate 110, and then the second substrate 120 can be formed on the first substrate 110. That is, the groove 101 is formed simultaneously during the fabrication process of the substrate 100.

[0082] For example, in some embodiments of this disclosure, such as Figures 7 to 9 As shown, the protective layer 300 on the surface of the bending region 12 facing away from the substrate 100 is approximately flush with the surface of the second substrate 120 on the display region facing away from the first substrate 110, thereby ensuring that the arrangement of the conductive layer 200 and the protective layer 300 does not increase the thickness of the bending region. For example, if the strength (e.g., elastic modulus) of the material of the protective layer 300 is approximately equal to the strength of the material of the second substrate 120, then the thickness of the protective layer 300 and the second substrate 120 can be designed to be approximately equal; if the strength of the material of the protective layer 300 is greater than the strength of the material of the second substrate 120, then the thickness of the protective layer 300 needs to be less than the thickness of the second substrate 120; if the strength of the material of the protective layer 300 is less than the strength of the material of the second substrate 120, then the thickness of the protective layer 300 needs to be greater than the thickness of the second substrate 120.

[0083] In at least one embodiment of this disclosure, because the substrate of the bending area is thinned, the thickness requirement of the protective layer is greatly reduced. Therefore, the display area can be fabricated in the same layer as part of the structure, thereby reducing the manufacturing process of the display panel and reducing costs.

[0084] For example, such as Figures 7 to 10 As shown, the display panel may also include a display function layer 400, which is located on the substrate 100 and in the display area 11. The display function layer 400 includes a pixel defining layer 410 and a plurality of light-emitting devices 420 defined by the pixel defining layer 410.

[0085] For example, the display panel includes a driving circuit layer 20 located on a substrate 100, the driving circuit layer 20 including a plurality of pixel driving circuits, and a display function layer 400 located on the driving circuit layer 20. The pixel defining layer 410 includes a plurality of openings, and the light-emitting device 420 includes an anode 421, a light-emitting function layer 422 and a cathode 423 sequentially stacked on the driving circuit layer 20, and the light-emitting function layer 422 of the light-emitting device 420 (e.g., its light-emitting layer) is located in the opening defined by the pixel defining layer 410.

[0086] In at least one embodiment of this disclosure, at least a portion of the protective layer 300 is co-layered and made of the same material as the pixel defining layer 410. The pixel defining layer 410 has a relatively large thickness and is fabricated using organic materials such as photoresist (e.g., polyimide comprising photoresist). Therefore, by simultaneously fabricating the protective layer 300 during the fabrication of the pixel defining layer 410, the protective layer 300 can have sufficient thickness, enabling it to incorporate organic materials to possess good cushioning and bending properties, thereby reducing the fabrication process of the display panel and lowering costs.

[0087] like Figure 10 As shown, the display panel may include an encapsulation layer 430 to encapsulate and protect the display functional layer. The encapsulation layer 430 may include a first inorganic encapsulation layer 431, an organic encapsulation layer 433, and a second inorganic encapsulation layer 432 stacked sequentially on the display functional layer. The organic encapsulation layer 433 is a planarization film layer with a relatively large thickness.

[0088] In at least one embodiment of this disclosure, the display panel further includes an encapsulation layer 430 covering the display functional layer. The encapsulation layer 430 includes an organic encapsulation layer 433, and at least a portion of the protective layer 300 is co-layered and made of the same material as the organic encapsulation layer. The organic encapsulation layer 433 has a relatively large thickness. By simultaneously preparing the protective layer 300 during the preparation of the pixel defining layer 410 and / or the organic encapsulation layer, the protective layer 300 can have sufficient thickness, enabling it to include organic materials to possess good cushioning and bending properties. This reduces the manufacturing process of the display panel and lowers costs.

[0089] In embodiments of this disclosure, the display panel may further include functional structures such as a touch panel, optical films, cover plates, and color filters, the types of which can be selected according to actual needs. For example, such as... Figure 11 As shown, the display panel includes an optical adhesive layer 500 and a cover plate 600 stacked on the display substrate. The cover plate 600 is located on the display side of the display functional layer 400 and is attached to the display panel by the optical adhesive layer 500 (such as OCA adhesive, pressure-sensitive adhesive, etc.).

[0090] For example, in at least one embodiment of this disclosure, such as Figure 11As shown, the display panel may also include a light-shielding layer 700, which can block the bent area portion after bending, that is, the tangential plane P perpendicular to the plane where area 1 is located passes through the light-shielding layer 700. For example, the light-shielding layer 700 may be formed on the side surface of the cover plate 600 facing the display functional layer 400.

[0091] For example, the light-shielding layer 700 can be formed using light-shielding materials such as ink.

[0092] For example, if a black matrix is ​​set in the display panel, the light-shielding layer 700 can be further designed to be integrally formed with the black matrix.

[0093] For example, in at least one embodiment of this disclosure, such as Figure 11 As shown, the display panel may further include a composite adhesive tape 810 and a support layer 820. The composite adhesive tape 810 and the support layer 820 are located on the side of the substrate 100 opposite to the display functional layer 400, and the support layer 820 is attached to the substrate 100 by the composite adhesive tape 810. The portions of the composite adhesive tape 810 and the support layer 820 located in the bending area 12 can be cut off to reduce the bending radius.

[0094] For example, in some embodiments of this disclosure, the support layer 820 may include a film layer such as foam or a reinforcing plate (also referred to as a support plate). In addition, the reinforcing plate may be further designed to include conductive materials such as metal to have electrostatic shielding function.

[0095] For example, such as Figure 11 As shown, after bending the display panel, a shim 830 can be set between the support layer 820 in the display area and the support layer 820 in the bonding area to adjust the bending radius.

[0096] In at least one embodiment of this disclosure, such as Figure 11 As shown, the bonding area of ​​the display panel can be used to bond the flexible circuit board 840 and the driver chip 850. For example, the driver chip 850 can be a driver chip for touch, and an additional driver chip for display can be provided on the flexible circuit board 840.

[0097] At least one embodiment of this disclosure provides a method for manufacturing the aforementioned display panel, such as... Figure 12 As shown, the preparation method may include the following steps S110 to S140.

[0098] S110, a carrier substrate is provided and a substrate is formed on the carrier substrate. The substrate is divided into a display area and a bending area. The portion of the substrate located in the bending area is thinned so that the thickness of the portion of the substrate located in the bending area is less than the thickness of the portion of the substrate located in the display area.

[0099] S120, depositing conductive material on a substrate to form a conductive layer, at least a portion of which is formed in the bending region.

[0100] S130, a protective layer is formed on the side of the conductive layer away from the substrate, at least a portion of the protective layer is formed in the bending region and covers the conductive layer, wherein the protective layer is formed to have a thickness such that the stress neutral layer of the bending region is located in the conductive layer.

[0101] S140, Remove the substrate.

[0102] In the method for manufacturing a display panel according to some embodiments of this disclosure, step S110 may include: after removing the carrier substrate, laser ablation is performed on the substrate in the bending area from the side of the substrate away from the protective layer to form a groove on the side of the substrate away from the protective layer.

[0103] For example, step S110 above may further include: forming a first substrate, a spacer layer and a second substrate sequentially on a carrier substrate; in the bending region, performing laser ablation on the first substrate and removing the portion of the first substrate located in the bending region so that the bottom of the groove is a plane, as follows.

[0104] like Figure 13A As shown, a first substrate 110, a spacer layer 130, and a second substrate 120 are sequentially formed on a carrier substrate 900. For example, a complete display panel can be fabricated on the carrier substrate 900 based on this.

[0105] like Figure 13B As shown, in the bending region 12, laser irradiation is performed from the back side of the display panel to ablate the portion of the first substrate 110 located in the bending region 12.

[0106] like Figure 13C As shown, the ablation portion of the first substrate 110 is removed to obtain the groove 101, thereby achieving thinning of the substrate 100.

[0107] In the method for manufacturing a display panel according to other embodiments of this disclosure, step S110 may include: forming a first film layer on a carrier substrate, etching the first film layer to remove the portion of the first film layer located in the bending region to form an opening, and the remaining portion of the first film layer forming a first substrate; forming a second substrate on the side of the first film layer away from the carrier substrate, wherein the portion of the second substrate located in the bending region fills the opening and conforms to the opening to form a groove, as detailed below.

[0108] like Figure 14A As shown, a first substrate 110 is formed on a carrier substrate 900, and the first substrate 110 is etched to form an opening.

[0109] like Figure 14BAs shown, a second substrate 120 is formed on a carrier substrate 900. The portion of the second substrate 120 covering the opening of the first substrate 110 conforms to the opening to form a groove 101.

[0110] like Figure 14C As shown, a conductive film layer is deposited on the second substrate 120, and the conductive film layer is patterned to form a conductive layer 200 with signal lines, and a protective layer 300 is formed on the conductive layer 200, the protective layer 300 filling the groove 101.

[0111] like Figure 14D As shown, the carrier substrate 900 can be peeled off. For example, the carrier substrate 900 can be peeled off from the display panel after the complete display panel is prepared from the carrier substrate 900.

[0112] It should be noted that during laser ablation of the first substrate, the corresponding groove portion of the first substrate can be removed during the laser ablation process; or, in the bending area, the first substrate can be separated from the adjacent film layer, such as the spacer layer or the second substrate, during the ablation process, and then the first substrate can be cut, for example, along the edge of the first groove, so that the ablated portion of the first substrate can be detached.

[0113] In the method for fabricating a display panel according to other embodiments of this disclosure, step S110 may include: sequentially depositing a first film layer and a second film layer on a carrier substrate, wherein the first film layer is formed between the carrier substrate and the second film layer, wherein the absorption rate of the first substrate for light in a first wavelength range is greater than the absorption rate of the second substrate for light in the first wavelength range; after removing the carrier substrate, in the bending region, laser ablation is performed on the first film layer from the side of the first film layer away from the second film layer, and the portion of the first film layer located in the bending region is removed to form a groove, wherein the remaining portion of the first film layer forms the first substrate, and the second film layer forms the second substrate, as detailed below.

[0114] like Figure 15A As shown, a first film layer 110a and a second film layer 120a are sequentially deposited on a carrier substrate 900. For example, the material of the first film layer 110a may include the conjugated polymer polyaramid, and the material of the second film layer 120a may be polyimide.

[0115] like Figure 15B As shown, in the bending area 12, the first film layer 110a is laser-ablated from the back side of the display panel. During this process, the first film layer 110a and the second film layer 120a will separate in the bending area 12.

[0116] like Figure 15CAs shown, the first film layer 110a is cut along the boundary of the bending region 12, and the portion of the first film layer 110a located in the bending region 12 will detach on its own to form a groove 101. During this process, if the surface of the second film layer 120a is subjected to laser ablation, a protrusion 102 will be formed at the bottom of the groove 101.

[0117] The above description is merely a preferred embodiment of this specification and is not intended to limit this specification. Any modifications or equivalent substitutions made within the spirit and principles of this specification should be included within the scope of protection of this specification.

Claims

1. A display panel, characterized in that, The display panel includes a display area, a bending area located on at least one side of the display area, and a bonding area, the bending area being located between the display area and the bonding area. The display panel also includes a padding block, a substrate, and a conductive layer and a protective layer located on the substrate. At least a portion of the conductive layer and the protective layer are located within the bending region. The conductive layer is situated between the protective layer and the substrate. The conductive layer includes a plurality of signal lines extending from the display area to the bonding area. The thickness of the portion of the substrate located in the bending region is less than the thickness of the portion of the substrate located in the display region, and in the bending region, the thickness of the protective layer is designed such that the stress neutral layer in the bending region is located within the conductive layer; In the bending region, a groove is provided on the side of the substrate facing away from the protective layer. The bottom of the groove has multiple protrusions. The substrate includes a first substrate and a second substrate stacked sequentially, with the second substrate located between the first substrate and the conductive layer. The groove is located in the first substrate, and the bottom of the groove is located on the surface of the second substrate. The absorption rate of the first substrate for light in a first wavelength range is greater than that of the second substrate for light in the first wavelength range. The light in the first wavelength range is a laser, and the groove is formed by ablation of the first substrate with a laser, wherein, during laser ablation of the first substrate, the surface of the second substrate is partially ablated to form the protrusion. In the display area, the side of the substrate facing away from the protective layer is the back side of the display area. The bonding area is bent to the back side of the display area when the display panel is bent. After the bending area is bent, the pad is located between the portion of the substrate located in the display area and the portion located in the bonding area, and the groove of the substrate faces the pad.

2. The display panel according to claim 1, characterized in that, The distance between the tips of adjacent protrusions is 5 to 20 micrometers, and / or the height of the protrusion is 1 to 10 micrometers.

3. The display panel according to claim 2, characterized in that, The material of the first substrate includes the conjugated polymer polyaromaticimide, and the material of the second substrate includes polyimide.

4. The display panel according to claim 1, characterized in that, Also includes: A display functional layer is located on the substrate and in the display area. The display functional layer includes a pixel delimiting layer and a plurality of light-emitting devices defined by the pixel delimiting layer.

5. The display panel according to claim 4, characterized in that, At least a portion of the protective layer is in the same layer and made of the same material as the pixel defining layer; and / or The display panel further includes an encapsulation layer covering the display functional layer, the encapsulation layer including an organic encapsulation layer, and at least a portion of the protective layer being in the same layer and made of the same material as the organic encapsulation layer.

6. A method for manufacturing a display panel, characterized in that, include: A carrier substrate is provided, and a substrate is formed on the carrier substrate, wherein the substrate is divided into a display area, a bending area, and a bonding area, the bending area being located between the display area and the bonding area, and the portion of the substrate located in the bending area is thinned such that the thickness of the portion of the substrate located in the bending area is less than the thickness of the portion of the substrate located in the display area, wherein a first film layer and a second film layer are sequentially formed on the carrier substrate, the first film layer being formed between the carrier substrate and the second film layer, wherein the absorption rate of the first film layer for light in a first wavelength range is greater than the absorption rate of the second film layer for light in the first wavelength range; A conductive material is deposited on the substrate to form a conductive layer, the conductive layer at least partially covering the bending area, wherein the conductive layer includes a plurality of signal lines extending from the display area to the bonding area; A protective layer is formed on the side of the conductive layer opposite to the substrate, the protective layer at least partially covering the bending region and the conductive layer, wherein the protective layer is formed to have a thickness such that a stress-neutral layer of the bending region is located in the conductive layer; Remove the carrier substrate; In the bending region, the first film layer is laser-ablated from the side opposite to the second film layer, removing the portion of the first film layer located in the bending region to form a groove. The bottom of the groove has multiple protrusions. The remaining portion of the first film layer forms a first substrate, and the second film layer forms a second substrate. The first substrate and the second substrate constitute the substrate. During laser ablation of the first substrate, the surface of the second substrate is partially ablated to form the protrusions. The absorption rate of the laser by the first substrate is greater than that by the second substrate. A raised block is formed on the side of the substrate opposite to the display functional layer, wherein the display functional layer is formed on the substrate and located in the display area, and the display functional layer includes a pixel defining layer and a plurality of light-emitting devices defined by the pixel defining layer; In the display area, the side of the substrate away from the protective layer is the back side of the display area, and the bonding area is bent to the back side of the display area when the display panel is bent. The padding block is located between the portion of the substrate located in the display area and the portion located in the bonding area, and the groove of the substrate faces the padding block.

7. The preparation method according to claim 6, characterized in that, The distance between the tips of adjacent protrusions is 5 to 20 micrometers, and / or the height of the protrusion is 1 to 10 micrometers.

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