Display panel and manufacturing method therefor

Abstract

A display panel (10) and a manufacturing method therefor. The display panel (10) comprises a display region (11) and a bending region (12) located on at least one side of the display region (11). The display panel (10) further comprises a substrate (100), and a conductive layer (200) and a protective layer (300) located on the substrate (100). The conductive layer (200) and the protective layer (300) are at least partially located in the bending region (12). The conductive layer (200) is located between the protective layer (300) and the substrate (100). The thickness of a portion of the substrate (100) located in the bending region (12) is less than the thickness of a portion of the substrate (100) located in the display region (11). In the bending region (12), the thickness of the protective layer (300) is designed such that a stress-neutral layer of the bending region (12) is located in the conductive layer (200).

Description

Display panel and manufacturing method thereof

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese Patent Application No. 202310953072.7, filed on July 31, 2023, entitled “Display Panel and Method for Preparing the Same,” and the entire contents of that application are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to the field of display technology, and in particular, to a display panel and a method for manufacturing the same. Background Art

[0004] With the widespread use of electronic display products in people's daily lives, users have increasingly higher demands on the appearance of electronic display products, especially the screen-to-body ratio. In response to this demand, electronic display products with full-screen display functions under the concepts of narrow bezels and no bezels have emerged.

[0005] The border area of ​​the display panel in an electronic display product can be bent toward its back, creating a visually narrow or borderless appearance. However, due to the structural design limitations of current electronic display products, the display panel is prone to damage during bending and is difficult to further reduce the bending radius.

[0006] Summary of the Invention

[0007] According to a first aspect of the present disclosure, a display panel is provided, comprising a display area and a bending area located on at least one side of the display area. The display panel further comprises a substrate, and a conductive layer and a protective layer located on the substrate. At least portions of the conductive layer and the protective layer are located in the bending area, with the conductive layer located 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.

[0008] A second aspect of the present disclosure provides a method for preparing a display panel, which includes: providing a carrying substrate and forming a base on the carrying substrate, wherein the base is divided into a display area and a bending area, thinning the portion of the base located in the bending area so that the thickness of the portion of the base located in the bending area is less than the thickness of the portion of the base located in the display area; depositing a conductive material on the base to form a conductive layer, wherein at least a portion of the conductive layer is formed in the bending area; forming a protective layer on a side of the conductive layer away from the base, wherein at least a portion of the protective layer is formed in the bending area and covers 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 carrying substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG1 is a schematic diagram of a planar structure of a display panel provided by an embodiment of the present disclosure.

[0010] FIG2 is a cross-sectional view of the display panel shown in FIG1 in a flattened state.

[0011] FIG3 is a cross-sectional view of the display panel shown in FIG2 in a bent state.

[0012] FIG4 is an enlarged view of a bending region of a display panel provided in one embodiment of the present disclosure.

[0013] FIG5 is an enlarged view of a bending region of another display panel provided in an embodiment of the present disclosure.

[0014] FIG6 is an enlarged view of a bending region of another display panel provided in an embodiment of the present disclosure.

[0015] FIG7 is a cross-sectional view of another display panel provided by an embodiment of the present disclosure in a flattened state.

[0016] FIG8 is a cross-sectional view of the display panel shown in FIG7 in a bent state.

[0017] FIG9 is an enlarged view of a bending region of another display panel provided in an embodiment of the present disclosure.

[0018] FIG10 is a cross-sectional view of a portion of a display area of ​​a display panel provided by an embodiment of the present disclosure.

[0019] FIG11 is a cross-sectional view of a display panel in a bent state provided by an embodiment of the present disclosure.

[0020] FIG12 is a flow chart of a method for manufacturing a display panel provided in one embodiment of the present disclosure.

[0021] 13A to 13C are process diagrams of a method for preparing a substrate of a display panel provided by an embodiment of the present disclosure.

[0022] 14A to 14D are process diagrams of a method for preparing a substrate of a display panel provided by an embodiment of the present disclosure.

[0023] 15A to 15C are process diagrams of a method for preparing a substrate of a display panel provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0024] Due to the demand for extremely narrow borders, some areas of the display panel (such as the bonding area, which can also be called the pad area, etc.) will be bent to the back, thereby reducing the width of the non-display area of ​​the display device, that is, reducing the border width of the display device. In order to meet the bendability requirement, the display panel needs to be a flexible panel (flexible as a whole or only the bending area is designed to be flexible). In this case, the thickness of the bending area of ​​the display panel will directly affect the stress generated during bending. If the stress during bending is too large, it will cause damage to the bending area of ​​the display panel, such as broken wiring, resulting in poor signal. In addition, due to the limitation of bending stress, the bending area of ​​the display panel needs to be set to a larger width to provide a sufficient bending radius, which will obviously also lead to the design size of the display panel cannot be further reduced.

[0025] At least one embodiment of the present disclosure provides a display panel and a method for manufacturing the same to at least solve the above-mentioned 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 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 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 so that the stress-neutral layer in the bending area is located in the conductive layer. In this solution, the stress generated when the substrate is bent can be reduced by thinning the substrate in the bending zone. In addition, in order to ensure that the stress-neutral layer in the bending zone 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. In this way, the bending stress generated in the bending zone of the display panel can be reduced, which is beneficial to reducing the bending radius of the bending zone, so as to facilitate the extremely narrow frame design of the display panel; in addition, as the bending radius of the bending zone decreases, the design width of the bending zone will also decrease accordingly, 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.

[0026] The following describes a display panel and its manufacturing method according to at least one embodiment of the present disclosure, with reference to the accompanying drawings. Furthermore, in these drawings, a spatial rectangular coordinate system is established with the substrate as a reference to illustrate the positional relationships of the various structures in the display substrate. In this spatial rectangular coordinate system, the X-axis and Y-axis are parallel to the surface of the substrate, the X-axis is parallel to the direction from the display area to the bending area, and the Z-axis is perpendicular to the surface of the substrate.

[0027] As shown in Figures 1 to 4, 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 physical 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 portions of the conductive layer 200 and the protective layer 300 are located in the bending area 12, with the conductive layer 200 located between the protective layer 300 and the substrate 100.

[0028] For example, the planar area of ​​the display panel 10 may further include a bonding area 13, with the bending area 12 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 external circuits (e.g., flexible circuit boards). For example, the conductive layer 200 may include a plurality of 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 actual use, the bending area 12 will bend (e.g., along the direction of the arrow in FIG. 2 ), so that the bonding area 13 bends to the back of the display area 11, thereby narrowing the border of the display panel 10.

[0029] When the display panel 10 is in a bent state, the bonding area 13 is located on the back side of the display area 11 (the other side opposite to the light emitting side). When the display panel 10 is in a flat state, the bonding area 13 is located on the side of the bending area 12 away from the display area 11.

[0030] In the embodiments of the present disclosure, after the display panel is bent, 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 offsetting 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. In addition, 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.

[0031] For example, in the bending zone 12, if the strength of the material of the protective layer 300 (such as the elastic modulus) is approximately equal to the strength of the material of the substrate 100, then the thickness 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.

[0032] The “stress neutral layer” is a virtual layer, which is the boundary between tensile stress and compressive stress in a stressed state (a bent state in the present disclosure). At this boundary, the target object is neither stretched nor compressed.

[0033] In the embodiments of the present disclosure, the method for thinning the portion of the substrate located in the bend region is not limited and can be selected based on 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 bend region are described separately through different embodiments.

[0034] In some embodiments of the present disclosure, as shown in FIG. 2 , the substrate 100 may be grooved in the bending region 12 to achieve thinning, that is, a groove 101 is provided on a side of the substrate 100 facing away from the protective layer 300 .

[0035] In some embodiments of the present disclosure, a photolithography process may be performed on the substrate 100 from the back side of the display panel to form the groove 101 on the substrate 100 .

[0036] In other embodiments of the present disclosure, the substrate 100 may be processed by ablation (eg, laser ablation) to form the groove 101 .

[0037] In the embodiments of the present disclosure, the substrate can be set as an integrated structure, and the degree of thinning (groove depth) can be controlled by controlling parameters such as the etching or ablation time. Alternatively, the substrate can be set as multiple film layers, and specific film layers can be etched to precisely control the depth of the groove.

[0038] For example, in some embodiments of the present disclosure, as shown in Figure 4, the 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 that defines different film layers.

[0039] For example, in some other embodiments of the present disclosure, as shown in FIG5 , the base 100 includes a first substrate 110 and a second substrate 120 stacked in sequence, the second substrate 120 being located between the first substrate 110 and the conductive layer 200, and the groove 101 being located in the first substrate 110. For example, the groove 101 can be formed only in the first substrate 110 by controlling the material difference between the first substrate 110 and the second substrate 120. 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.

[0040] In at least one embodiment of the present disclosure, as shown in Figures 4 and 5, the portion of the substrate 100 located at the bottom of the groove 101 can be unevenly etched using methods such as laser ablation, thereby microscopically causing the bottom of the groove 101 to have multiple protrusions 102. These protrusions 102 can increase the surface area of ​​the bottom of the groove 101, thereby increasing the stress release area of ​​the bending region 12 when the display panel is bent, thereby reducing the risk of stress concentration.

[0041] 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 (also referred to as thickness) of the protrusions 102 is approximately 1 to 10 micrometers.

[0042] For example, along a direction perpendicular to the surface of the substrate (when the substrate is in a flattened state), the cross-sectional shape of the surface of the protrusion 102 can be an arc shape, a parabola shape, a "V" shape, or the like.

[0043] As described in the aforementioned embodiments, regardless of whether the substrate is designed as an integrated structure or is designed to include multiple film layers (such as the first and second substrates), laser ablation can be performed to form a groove, and the depth of the groove can be designed according to the actual process requirements. Therefore, in the embodiments of the present disclosure, there is no restriction on the extension degree of the bottom of the groove and the protrusion formed on the bottom in the substrate.

[0044] For example, in some embodiments of the present disclosure, when the substrate is an integrated structure, the depth of the groove may be 1 / 4 to 3 / 4 of the thickness of the substrate before thinning (the thickness in the display area).

[0045] For example, in some other embodiments of the present disclosure, when the base includes multiple film layers such as a first substrate, a second substrate and a spacer layer, the bottom of the groove can be located in the first substrate, or can extend into the second substrate, or can be located in the boundary area between the first substrate and the second substrate, i.e., the spacer layer.

[0046] In other embodiments of the present disclosure, as shown in FIG6 , the substrate 100 may further include a spacer layer 130 located between the first substrate 110 and the second substrate 120, wherein the density of the spacer layer 130 is greater than that of the first substrate 110. In this way, during etching, the spacer layer 130 with high density can slow down the etching rate to avoid rapid etching to the second substrate 120, thereby preventing the substrate 100 from being over-etched. In addition, during ablation, the spacer layer 130 is relatively more resistant to ablation, thereby preventing the second substrate 120 from being over-ablated and falling off, thereby causing the ablated portion of the first substrate 110 to fall off and form the groove 101. This approach can make the bottom of the groove 101 relatively flat (i.e., the size of the protrusion is relatively small), and is conducive to controlling the depth of the groove 101, reducing the risk of the second substrate 120 being damaged during the process of forming the groove 101.

[0047] When the spacer layer 130 is provided, the bottom of the ablated groove 101 can be located in any layer of the first substrate 110, the second substrate 120 and the spacer layer 130, wherein, compared with the case where the bottom of the groove 101 is formed on the first substrate 110, when the bottom of the ablated groove 101 is located in the second substrate 120 or the spacer layer 130, due to the above-mentioned effect of the spacer layer 130, the size of the protrusion formed by ablation is relatively smaller.

[0048] For example, optionally, the first substrate 110 is an organic layer, and the spacer layer 130 is an inorganic layer. Compared with the organic layer, the inorganic layer has a relatively higher density and is resistant to ablation.

[0049] In at least one embodiment of the present disclosure, referring again to FIG. 5 , the base 100 includes a first substrate 110 and a second substrate 120 stacked in sequence. The second substrate 120 is located between the first substrate 110 and the conductive layer 200. The groove 101 is located in the first substrate 110. The first substrate 110 has a higher absorptivity for light within a first wavelength range than the second substrate 120. Thus, when the first substrate 110 is irradiated with light within the first wavelength range, the first substrate 110 absorbs more light and thereby separates from the second substrate 120. Consequently, after the portion of the first substrate 110 located in the bend region 12 is cut, it falls off directly without remaining on the second substrate 120. Furthermore, this approach generates less heat, thereby preventing adverse effects on components in the display panel, such as the driver circuit.

[0050] For example, optionally, when the first substrate 110 and the second substrate 120 are designed to have different absorptivity for light within a first wavelength range, the bottom of the groove 101 can be designed to have multiple protrusions to increase the stress release capability of the substrate 100 during bending. For example, when the first substrate 110 is ablated by the light, the surface of the second substrate 120 can be partially ablated, so that a protrusion appears at the bottom of the groove 101.

[0051] For example, optionally, the light in the first wavelength range is a laser. For example, the laser can be a laser generated by a carbon dioxide laser, which generates laser light by discharging carbon dioxide gas, and its wavelength can be around 10.6 microns; or, the laser can be a laser emitted by a laser diode, and its wavelength can be in the visible light range or the near-infrared range, for example, the wavelength can be 808 nanometers, 980 nanometers, or 1064 nanometers; or, the laser can be a laser generated by a yttrium neodymium oxide laser, and its wavelength can be 1064 nanometers; or, the laser can be a laser generated by a rubidium vapor laser, and its wavelength can be 780 nanometers. In the embodiments of the present disclosure, as long as the laser can be used to ablate the substrate, the method and type of its generation can be selected according to the needs of the actual process and are not limited here.

[0052] For example, optionally, the material of the first substrate 110 includes conjugated polymer polyarylimide (CPI for short), and the material of the second substrate 120 includes polyimide (PI for short).

[0053] In other embodiments of the present disclosure, as shown in Figures 7 to 9, the front surface of the substrate 100 can be thinned, that is, a groove 101 is provided on the side of the substrate 100 facing the protective layer 300 in the bending region 12. For example, in some processes, a display panel is prepared on a carrier substrate, and after the display panel is prepared, the carrier substrate is peeled off. In the above solution, the groove 101 is located on the front surface of the substrate 100. The groove 101 can be prepared simultaneously during the preparation of the substrate 100, eliminating the need to peel off the carrier substrate in advance, thereby reducing the difficulty of the display panel preparation process.

[0054] For example, in at least one embodiment of the present disclosure, as shown in Figures 7 to 9, the base 100 includes a first substrate 110 and a second substrate 120 stacked in sequence, the portion of the first substrate 110 located in the bending area 12 is provided with an opening, the portion of the second substrate 120 located in the bending area 12 fills the opening and conforms to the opening to form a groove 101, and the conductive layer 200 and the protective layer 300 fill the groove 101. In this way, the base 100 in the bending area 12 can be thinned before forming other film layers such as the conductive layer 200 on the base 100, without adversely affecting the performance of the display panel. For example, when preparing the base 100 on a carrier substrate, an opening located in the bending area 12 can be first formed in the first substrate 110, and then the second substrate 120 can be formed on the first substrate 110, that is, the groove 101 will be formed simultaneously in the process of preparing the base 100.

[0055] For example, in some embodiments of the present disclosure, as shown in Figures 7 to 9, the surface of the protective layer 300 in the bending region 12 facing away from the base 100 is substantially flush with the surface of the second substrate 120 in the display region facing away from the first substrate 110, so that the provision 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 substantially 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 substantially 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.

[0056] In at least one embodiment of the present disclosure, because the base of the bending area is thinned, the thickness requirement of the protective layer is greatly reduced. Therefore, it can be prepared in the same layer as part of the structure of the display area, thereby reducing the preparation process flow of the display panel and reducing costs.

[0057] For example, as shown in Figures 7 to 10, the display panel may further 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.

[0058] 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 the 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. The light-emitting function layer 422 of the light-emitting device 420 (e.g., the light-emitting layer included therein) is located in the opening defined by the pixel defining layer 410.

[0059] In at least one embodiment of the present disclosure, at least a portion of the protective layer 300 is formed from the same layer and material as the pixel defining layer 410. The pixel defining layer 410 is relatively thick and is made of an organic material such as a photoresist (e.g., a polyimide comprising a photoresist material). Therefore, during the preparation of the pixel defining layer 410, the protective layer 300 is simultaneously prepared. This allows the protective layer 300 to have a sufficient thickness, and the organic material of the protective layer 300 provides good cushioning and bending properties, thereby simplifying the display panel manufacturing process and reducing costs.

[0060] As shown in Figure 10, the display panel may include an encapsulation layer 430 to encapsulate and protect the display function 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 in sequence on the display function layer. The organic encapsulation layer 433 is a planarization film layer with a relatively large thickness.

[0061] In at least one embodiment of the present disclosure, the display panel further includes an encapsulation layer 430 covering the display function layer. The encapsulation layer 430 includes an organic encapsulation layer 433. At least a portion of the protective layer 300 is formed from the same layer and material as the organic encapsulation layer. The organic encapsulation layer 433 has a relatively large thickness. During the preparation of the pixel defining layer 410 and / or the organic encapsulation layer, the protective layer 300 is simultaneously prepared. This allows the protective layer 300 to have a sufficient thickness. The organic material included in the protective layer 300 provides good cushioning and bending properties, thus simplifying the display panel manufacturing process and reducing costs.

[0062] In the embodiments of the present disclosure, the display panel may further include functional structures such as a touch panel, an optical film, a cover plate, and a color filter. The types of these functional structures can be selected based on actual needs. For example, as shown in FIG11 , the display panel includes an optical adhesive layer 500 and a cover plate 600 stacked on a display substrate. The cover plate 600 is located on the display side of the display functional layer 400 . The cover plate 600 is bonded to the display panel via the optical adhesive layer 500 (e.g., OCA adhesive, pressure-sensitive adhesive, etc.).

[0063] For example, in at least one embodiment of the present disclosure, as shown in FIG11 , the display panel may further include a light shielding layer 700, which may shield the bent region after bending. That is, a section P passing through the bent region and perpendicular to the surface of region 1 passes through the light shielding layer 700. For example, the light shielding layer 700 may be formed on a surface of the cover plate 600 that faces the display function layer 400.

[0064] For example, the light shielding layer 700 can be formed using a light shielding material such as ink.

[0065] For example, when a black matrix is ​​provided in the display panel, the light shielding layer 700 may be further designed to be integrally formed with the black matrix.

[0066] For example, in at least one embodiment of the present disclosure, as shown in FIG11 , the display panel may further include a composite tape 810 and a support layer 820. The composite tape 810 and the support layer 820 are located on a side of the substrate 100 facing away from the display function layer 400, and the support layer 820 is adhered to the substrate 100 via the composite tape 810. Portions of the composite tape 810 and the support layer 820 located in the bending zone 12 may be removed to reduce the bending radius.

[0067] For example, in some embodiments of the present disclosure, the support layer 820 may include film layers such as foam and a reinforcement plate (also referred to as a support plate). In addition, the reinforcement plate may be further designed to include a conductive material such as metal to have an electrostatic shielding function.

[0068] For example, as shown in FIG. 11 , after the display panel is bent, a spacer 830 may be provided between the support layer 820 located in the display area and the support layer 820 located in the bonding area to adjust the bending radius.

[0069] In at least one embodiment of the present disclosure, as shown in FIG11 , 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 touch driver chip, and the flexible circuit board 840 can be provided with an additional driver chip for display.

[0070] At least one embodiment of the present disclosure provides a method for preparing the display panel mentioned above. As shown in FIG. 12 , the method may include the following steps S110 to S140 .

[0071] S110, providing a carrier substrate and forming a base on the carrier substrate, wherein the base is divided into a display area and a bending area, and thinning the portion of the base located in the bending area so that the thickness of the portion of the base located in the bending area is less than the thickness of the portion of the base located in the display area.

[0072] S120 , depositing a conductive material on the substrate to form a conductive layer, wherein at least a portion of the conductive layer is formed in the bending region.

[0073] S130, forming a protective layer on a side of the conductive layer away from the substrate, wherein 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 in the bending region is located in the conductive layer.

[0074] S140, removing the carrier substrate.

[0075] In the method for preparing a display panel of some embodiments of the present disclosure, the above-mentioned step S110 may include: after removing the carrying substrate, laser ablation is performed on the substrate in the bending area from the side of the substrate facing away from the protective layer to form a groove on the side of the substrate facing away from the protective layer.

[0076] For example, the above step S110 may also include: forming a first substrate, a spacer layer and a second substrate in sequence on the carrier substrate; performing laser ablation on the first substrate in the bending area, and removing the portion of the first substrate located in the bending area so that the bottom of the groove is flat, as follows.

[0077] As shown in FIG13A , 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 prepared on this basis.

[0078] As shown in FIG. 13B , laser irradiation is performed on the bending region 12 from the back side of the display panel to ablate the portion of the first substrate 110 located in the bending region 12 .

[0079] As shown in FIG. 13C , the ablated portion of the first substrate 110 is removed to obtain the groove 101 , thereby achieving thinning of the base 100 .

[0080] In the preparation method of the display panel of other embodiments of the present disclosure, the above-mentioned step S110 may include: forming a first film layer on a carrying substrate, etching the first film layer to remove the portion of the first film layer located in the bending area to form an opening, and the remaining portion of the first film layer forms a first substrate; forming a second substrate on the side of the first film layer away from the carrying substrate, wherein the portion of the second substrate located in the bending area fills the opening and is conformal with the opening to form a groove, as follows.

[0081] As shown in FIG. 14A , a first substrate 110 is formed on a carrier substrate 900 , and the first substrate 110 is etched to form an opening.

[0082] As shown in FIG. 14B , a second substrate 120 is formed on the carrier substrate 900 . A portion of the second substrate 120 covering the opening of the first substrate 110 is conformal to the opening to form a groove 101 .

[0083] As shown in FIG. 14C , a conductive film layer is deposited on the second substrate 120 and patterned to form a conductive layer 200 having a signal line. A protective layer 300 is formed on the conductive layer 200 to fill the groove 101 .

[0084] As shown in FIG. 14D , the carrier substrate 900 is peeled off. For example, after a complete display panel is prepared using the carrier substrate 900 , the carrier substrate 900 may be peeled off from the display panel.

[0085] When the first substrate is laser ablated, the portion of the first substrate corresponding to the groove can be removed during the laser ablation process; or, in the bending area, the first substrate is separated from the adjacent film layer, such as the spacer layer or the second substrate, during the ablation process, and then the first substrate is cut, such as along the edge of the first groove, so that the ablated portion of the first substrate falls off.

[0086] In the preparation method of the display panel of other embodiments of the present disclosure, the above-mentioned step S110 may include: depositing a first film layer and a second film layer in sequence on a carrying substrate, the first film layer being formed between the carrying substrate and the second film layer, wherein the absorption rate of the first substrate to light in the first wavelength range is greater than the absorption rate of the second substrate to light in the first wavelength range; after removing the carrying substrate, in the bending area, 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 area 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 follows.

[0087] As shown in Figure 15A, 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 conjugated polymer polyarylimide, and the material of the second film layer 120a may be polyimide.

[0088] As shown in FIG. 15B , at the bending region 12 , the first film layer 110 a is laser ablated from the back side of the display panel. During this process, the first film layer 110 a and the second film layer 120 a are separated at the bending region 12 .

[0089] As shown in FIG15C , the first film layer 110a is cut along the boundary of the bend region 12, and the portion of the first film layer 110a located in the bend region 12 falls off, thereby forming a groove 101. During this process, if the surface of the second film layer 120a is ablated by laser, a protrusion 102 is formed at the bottom of the groove 101.

Claims

1. A display panel, comprising a display area and a bending area located on at least one side of the display area, the display panel further comprising a substrate and a conductive layer and a protective layer located on the substrate, wherein: At least part of the conductive layer and the protective layer are located in the bending region, the conductive layer is located between the protective layer and the substrate, and 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 so that the stress-neutral layer in the bending area is located in the conductive layer.

2. The display panel according to claim 1, wherein: Also includes a bonding area, wherein the bending area is located between the display area and the bonding area, and The conductive layer includes a plurality of signal lines extending from the display area to the bonding area.

3. The display panel according to claim 1 or 2, wherein: In the bending area, a groove is arranged on a side of the substrate facing away from the protective layer.

4. The display panel according to claim 3, wherein: The bottom of the groove is provided with a plurality of protrusions.

5. The display panel according to claim 4, wherein: The distance between the tops of adjacent protrusions is 5 to 20 micrometers, and / or the height of the protrusions is 1 to 10 micrometers.

6. The display panel according to claim 3, wherein: The base includes a first substrate and a second substrate stacked in sequence, the second substrate is located between the first substrate and the conductive layer, and the groove is located in the first substrate.

7. The display panel according to claim 6, wherein: The bottom of the groove is located in the first substrate, or extends into the second substrate, or is located in a boundary region between the first substrate and the second substrate.

8. The display panel according to claim 7, wherein: The substrate further comprises a spacer layer between the first substrate and the second substrate, wherein the density of the spacer layer is greater than the density of the first substrate; Wherein, the first substrate is an organic layer, and the spacer layer is an inorganic layer.

9. The display panel according to claim 3, wherein: The base includes a first substrate and a second substrate stacked in sequence, the second substrate is located between the first substrate and the conductive layer, and The groove is located in the first substrate, and the absorptivity of the first substrate to light within a first wavelength range is greater than the absorptivity of the second substrate to light within the first wavelength range.

10. The display panel according to claim 9, wherein: The bottom of the groove is located on the surface of the second substrate.

11. The display panel according to claim 9 or 10, wherein: The light in the first wavelength range is laser; And / or, the material of the first substrate includes conjugated polymer polyaromatic imide, and the material of the second substrate includes polyimide.

12. The display panel according to claim 1 or 2, wherein: In the bending region, a groove is provided on a side of the substrate facing the protective layer.

13. The display panel according to claim 12, wherein: The base includes a first substrate and a second substrate stacked in sequence, wherein a portion of the first substrate located in the bending region is provided with an opening, and a portion of the second substrate located in the bending region fills the opening and conforms to the opening. forming the groove, and The conductive layer and the protective layer fill the groove.

14. The display panel according to claim 1 or 2, wherein: Also includes: The display function layer is located on the substrate and in the display area, and the display function layer includes a pixel defining layer and a plurality of light emitting devices defined by the pixel defining layer.

15. The display panel according to claim 14, wherein: At least a portion of the protection layer is in the same layer and made of the same material as the pixel definition layer; and / or The display panel further includes an encapsulation layer covering the display function layer, the encapsulation layer includes an organic encapsulation layer, and at least a portion of the protection layer is in the same layer and made of the same material as the organic encapsulation layer.

16. A method for preparing a display panel, comprising: Providing a carrier substrate and forming a base on the carrier substrate, wherein the base is divided into a display area and a bending area, and thinning a portion of the base located in the bending area so that the thickness of the portion of the base located in the bending area is smaller than the thickness of the portion of the base located in the display area; Depositing a conductive material on the substrate to form a conductive layer, wherein at least a portion of the conductive layer covers the bending region; forming a protective layer on a side of the conductive layer facing away from the substrate, wherein at least a portion of the protective layer covers the bending region and 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; and The carrier substrate is removed.

17. The preparation method according to claim 16, wherein: The step of thinning the portion of the substrate located in the bending area so that the thickness of the portion of the substrate located in the bending area is smaller than the thickness of the portion of the substrate located in the display area comprises: After removing the carrier substrate, laser ablation is performed on the substrate in the bending region from a side of the substrate away from the protective layer to form a groove on a side of the substrate away from the protective layer; Wherein, a plurality of protrusions are formed at the bottom of the groove, the distance between the top ends of adjacent protrusions is 5 to 20 microns, and / or the height of the protrusions is 1 to 10 microns.

18. The preparation method according to claim 17, wherein: The step of thinning the portion of the substrate located in the bending area so that the thickness of the portion of the substrate located in the bending area is smaller than the thickness of the portion of the substrate located in the display area comprises: forming a first substrate, a spacer layer, and a second substrate in sequence on the carrier substrate, wherein the first substrate, the spacer layer, and the second substrate constitute the base; In the bending region, laser ablation is performed on the base from a side of the first substrate facing away from the second substrate, and at least a portion of the first substrate located in the bending region is removed, so that the bottom of the groove is a plane; 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 to the boundary area between the first substrate and the second substrate; And / or, the first substrate is an organic layer, and the spacer layer is an inorganic layer.

19. The preparation method according to claim 16, wherein: The step of thinning the portion of the substrate located in the bending area so that the thickness of the portion of the substrate located in the bending area is smaller than the thickness of the portion of the substrate located in the display area comprises: forming a first film layer on the carrier substrate, etching the first film layer to remove a portion of the first film layer located in the bending area to form an opening, and the remaining portion of the first film layer forms a first substrate; and A second substrate is formed on a side of the first film layer away from the carrier substrate, wherein the second substrate is located The portion 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 the base.

20. The preparation method according to claim 16, wherein: The step of thinning the portion of the substrate located in the bending area so that the thickness of the portion of the substrate located in the bending area is smaller than the thickness of the portion of the substrate located in the display area comprises: forming a first film layer and a second film layer in sequence on the carrier substrate, wherein the first film layer is formed between the carrier substrate and the second film layer, wherein the absorptivity of the first film layer to light in a first wavelength range is greater than the absorptivity of the second film layer to light in the first wavelength range; and After removing the carrier substrate, in the bending region, laser ablation is performed on the first film layer from a side of the first film layer away from the second film layer, and a 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 a first substrate, the second film layer forms a second substrate, and the first substrate and the second substrate constitute the base; Wherein, a plurality of protrusions are formed at the bottom of the groove, the distance between the top ends of adjacent protrusions is 5 to 20 microns, and / or the height of the protrusions is 1 to 10 microns.

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