Foldable display device

Abstract

A foldable display device includes a display panel, the display panel includes a first non-folded area, a folding area and a second non-folded area arranged in sequence along a first direction, and the first non-folded area, the folding area and the second non-folded area all extend along a second direction, the first direction intersects the second direction; the folding area is configured to switch between a folded state and a flattened state; the display panel includes a flexible substrate and a support, a separation layer and a hinge arranged in sequence on one side of the flexible substrate; the support, the separation layer and the hinge are all located in the folding area; the display panel further includes a barrier layer, the barrier layer includes at least one of a first barrier layer and a second barrier layer, the first barrier layer is arranged between the separation layer and the hinge, and is used to block the contact between the separation layer and the hinge; the second barrier layer is arranged between the support and the separation layer, and is used to block the movement of part of the separation layer with the support, so that the folding abnormal sound can be avoided.

Description

Technical Field

[0001] This article relates to, but is not limited to, the field of display technology, and in particular to a foldable display device. Background Technology

[0002] Organic light-emitting diodes (OLEDs) and quantum dot light-emitting diodes (QLEDs) are active-matrix display devices with advantages such as self-illumination, wide viewing angle, high contrast, low power consumption, extremely high response speed, thinness, flexibility, and low cost. With the continuous development of display technology, flexible displays using OLEDs or QLEDs as light-emitting devices and controlled by thin-film transistors (TFTs) have become the mainstream products in the display field.

[0003] Currently, existing foldable display devices suffer from creaking noises when folded. Summary of the Invention

[0004] This disclosure provides a foldable display device that can solve the problem of abnormal folding noise in existing foldable display devices.

[0005] This disclosure provides a foldable display device, including a display panel. The display panel includes a first non-foldable area, a bending area, and a second non-foldable area arranged sequentially along a first direction. The first non-foldable area, the bending area, and the second non-foldable area all extend along a second direction, and the first direction intersects the second direction. The bending area is configured to switch between a folded state and a flattened state.

[0006] In a plane perpendicular to the display panel, the display panel includes a flexible substrate and a support member, an isolation layer, and a hinge located sequentially on one side of the flexible substrate; the support member, the isolation layer, and the hinge are all located in the bending area;

[0007] The display panel further includes a barrier layer, which includes at least one of a first barrier layer and a second barrier layer. The first barrier layer is disposed between the isolation layer and the hinge and is used to prevent the isolation layer from contacting the hinge. The second barrier layer is disposed between the support member and the isolation layer and is used to prevent a portion of the isolation layer from moving with the support member.

[0008] In an exemplary embodiment, the support member has a patterned area, the orthographic projection of the isolation layer onto the plane of the display panel includes the orthographic projection of the patterned area onto the plane of the display panel, and the orthographic projection area of ​​the isolation layer onto the plane of the display panel is larger than the orthographic projection area of ​​the patterned area onto the plane of the display panel; the orthographic projection of the first barrier layer onto the plane of the display panel is located within the orthographic projection of the isolation layer onto the plane of the display panel.

[0009] In an exemplary embodiment, the bending region has a second central axis extending along the second direction; the first barrier layer includes a first barrier portion and a second barrier portion arranged at intervals along the first direction, and the first barrier portion and the second barrier portion are symmetrical about the second central axis; the hinge is symmetrical about the second central axis, and the hinge is in contact with both the first barrier portion and the second barrier portion, and the surface energy of the first barrier portion and the surface energy of the second barrier portion are both less than the surface energy of the isolation layer.

[0010] In one exemplary embodiment, the display panel further includes an adhesive layer located between the first barrier portion and the second barrier portion, and the adhesive layer is used to bond the isolation layer and the hinge.

[0011] In one exemplary embodiment, the first barrier layer includes at least one of an ink layer, a silicone oil layer, or a graphene layer.

[0012] In one exemplary embodiment, the thickness of the first barrier layer ranges from 2.0 micrometers to 6.0 micrometers.

[0013] In an exemplary embodiment, the support member has a patterned area, the orthographic projection of the isolation layer onto the plane of the display panel includes the orthographic projection of the patterned area onto the plane of the display panel, and the orthographic projection area of ​​the isolation layer onto the plane of the display panel is larger than the orthographic projection area of ​​the patterned area onto the plane of the display panel; the orthographic projection of the second barrier layer onto the plane of the display panel is located within the orthographic projection of the isolation layer onto the plane of the display panel.

[0014] In an exemplary embodiment, the orthographic projection of the second barrier layer onto the plane of the display panel is located within the orthographic projection of the patterned area onto the plane of the display panel.

[0015] In one exemplary embodiment, the bending region has a second central axis extending along the second direction; the orthographic projection of the patterned region onto the plane of the display panel is symmetrical along the second central axis, and the orthographic projection of the second barrier layer onto the plane of the display panel is symmetrical along the second central axis.

[0016] In an exemplary embodiment, the isolation layer has a first edge in the orthographic projection of the plane where the display panel is located, and the second barrier layer has a second edge in the orthographic projection of the plane where the display panel is located. The first edge surrounds the second edge, and the first edge and the second edge together form a ring.

[0017] In one exemplary embodiment, the annulus has a ring width ranging from 3.0 micrometers to 10 micrometers.

[0018] In an exemplary embodiment, the size of the second barrier layer projected onto the plane of the display panel along the first direction ranges from 3.0 micrometers to 5.0 micrometers.

[0019] In one exemplary embodiment, the flexible substrate includes a first adhesive layer, a flexible layer, and a second adhesive layer stacked sequentially, with the first adhesive layer being closer to the support than the second adhesive layer; the flexible layer is made of polyimide, and the thickness of the flexible layer ranges from 10 micrometers to 25 micrometers.

[0020] In an exemplary embodiment, the display panel further includes a third adhesive layer, a fourth adhesive layer, and a fifth adhesive layer sequentially located on the side of the flexible substrate away from the support member; the first adhesive layer has a first elastic modulus, the second adhesive layer has a second elastic modulus, the third adhesive layer has a third elastic modulus, the fourth adhesive layer has a fourth elastic modulus, and the fifth adhesive layer has a fifth elastic modulus; wherein the first elastic modulus, the second elastic modulus, the fourth elastic modulus, and the fifth elastic modulus are all greater than the third elastic modulus.

[0021] In an exemplary embodiment, the first elastic modulus is equal to the second elastic modulus, and the fourth elastic modulus is equal to the fifth elastic modulus.

[0022] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description

[0023] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0024] Figure 1 This is a top view schematic diagram of a foldable display device according to an embodiment of the present disclosure;

[0025] Figure 2AThis is a schematic diagram of a foldable display device in a folded state;

[0026] Figure 2B This is a schematic diagram of another foldable display device in a folded state;

[0027] Figure 3 This is a partial top view of the foldable display device according to an embodiment of the present disclosure. Figure 1 ;

[0028] Figure 4 for Figure 3 Cross-sectional view of the area marked AA in the middle;

[0029] Figure 5 This is a schematic diagram of the foldable display device in a flattened state according to an embodiment of the present disclosure;

[0030] Figure 6 This is a schematic diagram of the foldable display device in a folded state according to an embodiment of the present disclosure;

[0031] Figure 7 This is a partial top view of a foldable display device according to an embodiment of the present disclosure;

[0032] Figure 8 for Figure 7 A cross-sectional view of the area marked BB.

[0033] Figure label:

[0034] 100 - Foldable display device; 101 - Display panel; 200 - First non-foldable area; 201 - First display area; 202 - First peripheral area; 202-1 - First upper frame area; 202-2 - First lower frame area; 202-3 - Left frame area; 300 - Second non-foldable area; 301 - Second display area; 302 - Second peripheral area; 302-1 - Second upper frame area; 302-2 - Second lower frame area; 302-3 - Right frame area; 400 - Bending area; 401 - First central axis; 402 - Second central axis; 403 - Third central axis; 110 - Flexible substrate; 111 - Flexible composite layer; 111-1 - First adhesive layer; 111- 2-Second adhesive layer, 111-3-Flexible layer, 112-First protective layer, 113-Display structure layer, 114-Third adhesive layer, 115-First encapsulation layer, 116-Fourth adhesive layer, 117-Cover layer, 118-Fifth adhesive layer, 119-Second encapsulation layer, 119-1-Black film layer, 119-2-Protective layer, 120-Support member, 121-Patterned area, 130-Isolation layer, 13A-First edge, 140-Barrier layer, 141-First barrier layer, 141-1-First barrier portion, 141-2-Second barrier portion, 141-3-Gap area, 142-Second barrier layer, 14A-Second edge, 143-Adhesive layer, 150-Hinge. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The implementation can be carried out in many different forms. Those skilled in the art will readily understand that the methods and content can be transformed into one or more forms without departing from the spirit and scope of this disclosure. Therefore, this disclosure should not be construed as limited to the content described in the following embodiments. Without conflict, the embodiments and features in the embodiments of this disclosure can be arbitrarily combined with each other.

[0036] In the accompanying drawings, the size of one or more constituent elements, the thickness of layers, or areas are sometimes exaggerated for clarity. Therefore, this disclosure is not necessarily limited to these dimensions, and the shapes and sizes of the components in the drawings do not reflect true proportions. Furthermore, the drawings schematically illustrate ideal examples, and this disclosure is not limited to the shapes or values ​​shown in the drawings.

[0037] The ordinal numbers such as "first," "second," and "third" in this disclosure are used to avoid confusion among the constituent elements, not to limit the quantity. "Multiple" in this disclosure includes two or more quantities.

[0038] In this disclosure, for convenience, terms such as "middle," "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer" are used to indicate orientation or positional relationships in conjunction with the accompanying drawings. This is solely for the purpose of facilitating the description and simplification of the specification, and does not imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this disclosure. The positional relationships of the constituent elements may be appropriately changed depending on the direction in which the constituent elements are described. Therefore, the description is not limited to the terms used in the specification and may be appropriately replaced as appropriate.

[0039] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection via an intermediate component, or a connection within two components. Those skilled in the art will understand the meaning of these terms in this disclosure as appropriate.

[0040] In this disclosure, a transistor is a device that includes at least three terminals: a gate electrode, a drain electrode, and a source electrode. A transistor has a channel region between the drain electrode (drain electrode terminal, drain region, or drain) and the source electrode (source electrode terminal, source region, or source), and current can flow through the drain electrode, the channel region, and the source electrode. In this disclosure, the channel region refers to the region through which current primarily flows.

[0041] In this disclosure, the first electrode can be the drain electrode and the second electrode can be the source electrode, or vice versa. In cases where transistors with opposite polarities are used or the current direction changes during circuit operation, the functions of the "source electrode" and the "drain electrode" are sometimes interchanged. Therefore, in this disclosure, the "source electrode" and the "drain electrode" can be interchanged.

[0042] In this disclosure, "electrical connection" includes the situation where constituent elements are connected together by a component having a certain electrical function. There are no particular limitations on the "component having a certain electrical function," as long as it enables the transmission and reception of electrical signals between the connected constituent elements. Examples of "component having a certain electrical function" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other components having one or more functions.

[0043] In this disclosure, "parallel" refers to a state in which the angle formed by two straight lines is greater than or equal to -10° and less than 10°, and therefore can include a state in which the angle is greater than or equal to -5° and less than 5°. Furthermore, "perpendicular" refers to a state in which the angle formed by two straight lines is greater than or equal to 80° and less than 100°, and therefore can include a state in which the angle is greater than or equal to 85° and less than 95°.

[0044] In this disclosure, the terms "film" and "layer" can be interchanged. For example, sometimes "conductive layer" can be replaced with "conductive film". Similarly, sometimes "insulating film" can be replaced with "insulating layer".

[0045] In this disclosure, “about” means a value that is not strictly limited and allows for process and measurement errors.

[0046] This disclosure provides a foldable display device, which includes a display panel. The display panel includes a first non-foldable area, a bending area, and a second non-foldable area arranged sequentially along a first direction. The first non-foldable area, the bending area, and the second non-foldable area all extend along a second direction, and the first direction intersects the second direction. The bending area is configured to switch between a folded state and a flattened state.

[0047] In a plane perpendicular to the display panel, the display panel includes a flexible substrate and a support member, an isolation layer, and a hinge located sequentially on one side of the flexible substrate; the support member, the isolation layer, and the hinge are all located in the bending area;

[0048] The display panel further includes a barrier layer, which includes at least one of a first barrier layer and a second barrier layer. The first barrier layer is disposed between the isolation layer and the hinge and is used to prevent the isolation layer from contacting the hinge. The second barrier layer is disposed between the support member and the isolation layer and is used to prevent a portion of the isolation layer from moving with the support member.

[0049] In this embodiment of the disclosure, by setting a barrier layer, the first barrier layer can block the contact between the isolation layer and the hinge, which can avoid friction noise during the use of the foldable display device. The second barrier layer can block part of the isolation layer from moving with the support member, that is, it can prevent the isolation layer from being extended or compressed with the support member, which can improve the quality of the foldable display device and improve the user's perceived comfort.

[0050] Figure 1 This is a top view schematic diagram of a foldable display device according to an embodiment of this disclosure. Figure 1 As shown, the foldable display device 100 may include a display panel 101. For example, the orthographic projection of the display panel 101 into the plane formed by the first direction X and the second direction Y may be rectangular, etc. The plane containing the display panel 101 is parallel to the plane formed by the first direction X and the second direction Y. The display panel 101 may include a bending area 400 and a non-bending area. The non-bending area includes at least a first non-folding area 200 and a second non-folding area 300 spaced apart along the first direction X. The first non-folding area 200, the bending area 400, and the second non-folding area 300 may be arranged sequentially along the first direction X. In this embodiment, the bending area refers to the area where the display panel needs to be bent when bent, and the non-folding area refers to the area where the display panel does not bend or bends only slightly when bent.

[0051] In one exemplary embodiment, such as Figure 1 As shown, the bending area 400 can be configured as a strip extending along the second direction Y, and the first non-folding area 200 and the second non-folding area 300 can both be rectangular. The bending area 400 can have a first central axis 401 extending along the first direction X and a second central axis 402 extending along the second direction Y. For example, the first non-folding area 200 and the second non-folding area 300 can be configured to be symmetrical along both the first central axis 401 and the second central axis 402. For example, the display panel 101 can be configured to be symmetrical along both the first central axis 401 and the second central axis 402.

[0052] In one exemplary embodiment, such as Figure 1 As shown, the first non-folding area 200 may include a first display area 201 and a first peripheral area 202 located on at least one side of the first display area 201. The second non-folding area 300 may include a second display area 301 and a second peripheral area 302 located on at least one side of the second display area 301.

[0053] In one exemplary embodiment, the first display area 201 may include a flexible substrate and a display structure layer disposed on the flexible substrate. The flexible substrate may be made of materials such as polyimide (PI), polyethylene terephthalate (PET), or a surface-treated polymer film, and may also include silicon nitride (SiN). x ) or silicon oxide (SiO) x Inorganic materials, such as [insert inorganic materials here], can improve the water and oxygen resistance of the flexible substrate. The design of the second display area 301 can refer to the design of the first display area 201, and will not be elaborated further here.

[0054] In one exemplary embodiment, the display structure layer may include a plurality of pixel units (each pixel unit includes a plurality of sub-pixels), a plurality of gate lines, and a plurality of data lines. The plurality of data lines may extend along a second direction Y, and the plurality of gate lines may extend along a first direction X. The orthographic projections of the plurality of gate lines and the plurality of data lines onto the flexible substrate may intersect to form a plurality of sub-pixel regions. A sub-pixel is disposed within one sub-pixel region. The plurality of data lines are electrically connected to the plurality of sub-pixels and are configured to provide data signals to the plurality of sub-pixels. The plurality of gate lines are electrically connected to the plurality of sub-pixels and are configured to provide gate drive signals to the plurality of sub-pixels.

[0055] In one exemplary embodiment, a pixel unit may include at least three sub-pixels, which may be red, green, and blue sub-pixels, respectively. The three sub-pixels may be arranged horizontally side-by-side, vertically side-by-side, or in a triangular arrangement; this embodiment of the present disclosure does not limit this arrangement. For example, a pixel unit may include four sub-pixels, which may be red, green, blue, and white sub-pixels, respectively. The four sub-pixels may be arranged horizontally side-by-side, vertically side-by-side, or in a square arrangement.

[0056] In an exemplary embodiment, at least one sub-pixel may include a pixel circuit and a light-emitting element. The pixel circuit may be configured to drive the electrically connected light-emitting element. For example, the pixel circuit may include multiple transistors and at least one capacitor. For example, the pixel circuit may be a 3T1C, 4T1C, 5T1C, 5T2C, 6T1C, 7T1C, or 8T1C structure. In the above circuit structures, T refers to a thin-film transistor, C refers to a capacitor, the number before T represents the number of thin-film transistors in the circuit, and the number before C represents the number of capacitors in the circuit.

[0057] In one exemplary embodiment, the multiple transistors in the pixel circuit can be either P-type transistors or N-type transistors. Using the same type of transistors in the pixel circuit can simplify the manufacturing process, reduce the manufacturing difficulty of the display panel, and improve product yield. In other examples, the multiple transistors in the pixel circuit may include both P-type and N-type transistors.

[0058] In one exemplary embodiment, the multiple transistors in the pixel circuit can be low-temperature polysilicon (LTPS) thin-film transistors (TFTs), oxide thin-film transistors (OPTs), or a combination of both. The active layer of the LTPS TFT is made of low-temperature polysilicon (LTPS), while the active layer of the OPT TFT is made of oxide semiconductor. LTPS TFTs offer advantages such as high mobility and fast charging, while OPTs offer advantages such as low leakage current. Integrating LTPS and OPTs onto a single display panel, i.e., an LTPS+Oxide (LTPO) display panel, leverages the advantages of both, enabling low-frequency driving, reducing power consumption of the display device, and improving display quality.

[0059] In one exemplary embodiment, the light-emitting element can be any of the following: a light-emitting diode (LED), an organic light-emitting diode (OLED), a quantum dot light-emitting diode (QLED), or a micro-LED (including mini-LED or micro-LED). For example, the light-emitting element can be an OLED, which can emit red, green, blue, or white light under the drive of its corresponding electrically connected pixel circuit. The color of the light emitted by the light-emitting element can be determined as needed. In some examples, the light-emitting element may include an anode, a cathode, and an organic light-emitting layer located between the anode and the cathode. The anode of the light-emitting element can be electrically connected to the corresponding pixel circuit, which is not limited in this disclosure.

[0060] In one exemplary embodiment, the first peripheral region 202 may include bonding circuitry for connecting signal lines to an external driving device. For example, the bonding circuitry may be electrically connected to the external driving device via a flip-chip film. The first peripheral region 202 may also include gate driving circuitry and a second power line VSS for transmitting voltage signals to a plurality of sub-pixels. The second peripheral region 302 may be designed with reference to the first peripheral region 202, and will not be described in detail here.

[0061] In one exemplary embodiment, such as Figure 1 As shown, the first peripheral area 202 may include a first upper border area 202-1, a first lower border area 202-2, and a left border area 202-3 connected to each other. There is a gap along a second direction Y between the first upper border area 202-1 and the first lower border area 202-2, and the left border area 202-3 is located between the first upper border area 202-1 and the first lower border area 202-2. A first end of the first upper border area 202-1 may be connected to a first end of the left border area 202-3, and a second end of the first upper border area 202-1 may extend along a first direction X. A first end of the first lower border area 202-2 may be connected to a second end of the left border area 202-3, and a second end of the first lower border area 202-2 may extend along the first direction X. The left border area 202-3 may extend along the second direction Y. In one example, the bonding circuitry may be located in the first lower border area 202-2.

[0062] In one exemplary embodiment, such as Figure 1As shown, the second peripheral area 302 may include a second upper border area 302-1, a second lower border area 302-2, and a right border area 302-3 connected to each other. There is a gap along the second direction Y between the second upper border area 302-1 and the second lower border area 302-2, and the right border area 302-3 is located between the second upper border area 302-1 and the second lower border area 302-2. The first end of the second upper border area 302-1 can be connected to the first end of the right border area 302-3, and the second end of the second upper border area 302-1 can extend in the opposite direction of the first direction X. The second end of the second upper border area 302-1 can be connected to the second end of the first upper border area 302-1. The first end of the second lower border area 302-2 can be connected to the second end of the right border area 302-3, and the second end of the second lower border area 302-2 can extend in the opposite direction of the first direction X. The second end of the second lower border area 302-2 can be connected to the second end of the first lower border area 302-2. The right frame region 302-3 may extend along the second direction Y. In one example, the bonding circuit may be located in the second lower frame region 302-2. Alternatively, a portion of the bonding circuit may be located in the first lower frame region 202-2, and other portions of the bonding circuit may be located in the second lower frame region 302-2.

[0063] In an exemplary embodiment, the display panel 101 may include a plurality of bending areas 400. The number, division method, and positional relationship of the bending areas and non-folding areas can be determined according to actual needs, and are not limited herein. In the illustrative embodiment of this disclosure, the technical solution is described using the example of a display panel 101 comprising three parts: a bending area 400 and a first non-folding area 200 and a second non-folding area 300 respectively disposed on both sides of the bending area 400.

[0064] Figure 2A This is a schematic diagram of a foldable display device in a folded state. Figure 2B This is a schematic diagram of another foldable display device in a folded state. Figure 2A As shown, the foldable display device 100 can achieve an inward folding state, with a folding angle ranging from 0 degrees to 180 degrees. For example... Figure 2B As shown, the foldable display device 100 can be folded outwards, and the folding angle can range from 180 degrees to 360 degrees. In this embodiment of the disclosure, the folding angle range of the foldable display device 100 is not limited.

[0065] Figure 3 This is a partial top view of the foldable display device according to an embodiment of the present disclosure. Figure 1 , Figure 4 for Figure 3A cross-sectional view at point AA is shown. In this embodiment, the plane perpendicular to the display panel can be the plane formed by the first direction X and the third direction Z, or the plane formed by the second direction Y and the third direction Z. In this embodiment, the third direction Z can also be referred to as the thickness direction of the display panel. In this embodiment, the first direction X, the second direction Y, and the third direction Z can be mutually perpendicular. Figure 3 , Figure 4 As shown, the display panel may further include a support member 120 located on one side of the flexible substrate 110. The support member 120 is configured to switch between a bent state and an initial state along with the display panel 101. When the foldable display device is in the folded state, the support member 120 can bend along with the display panel 101, and the support member 120 is in the bent state. When the foldable display device is in the flattened state, the support member 120 can return from the bent state to the initial state. In this embodiment of the present disclosure, the flattened state of the foldable display device, i.e., the angle between the first non-folded area and the second non-folded area, is 180 degrees. The foldable display device is in the folded state when the display panel is in the folded state. The foldable display device is in the flattened state when the display panel is in the flattened state.

[0066] Figure 4 As shown, the support member 120 can be symmetrical about itself along the third central axis 403. The third central axis 403 can pass through the center of the bending area 400 and extend along the third direction Z. The orthographic projection of the support member 120 onto the plane where the display panel is located can include the orthographic projection of the bending area 400 onto the plane where the display panel is located. In this embodiment of the present disclosure, the plane where the display panel is located is the plane formed by the first direction X and the second direction Y. The support member 120 has a patterned area 121, which can include multiple holes. The multiple holes can all be through holes or blind holes, or some of the holes can be through holes and the remaining holes can be blind holes. The diameters of the multiple holes can be the same or different. In one example, the holes can include any one of the following: circular holes, elliptical holes, rectangular holes, pentagonal holes, etc.

[0067] Figure 4 As shown, the orthographic projection of the pattern area 121 onto the plane of the display panel can be located within the orthographic projection of the bending area 400 onto the plane of the display panel. For example, the edge of the orthographic projection of the pattern area 121 onto the plane of the display panel can coincide with the edge of the orthographic projection of the bending area 400 onto the plane of the display panel.

[0068] In an exemplary embodiment, the size of the orthographic projection of the patterned area 121 onto the plane of the display panel along a first direction can range from 130 micrometers to 160 micrometers, and the size of the orthographic projection of the patterned area 121 onto the plane of the display panel along a second direction can also range from 130 micrometers to 160 micrometers. For example, the orthographic projection of the patterned area 121 onto the plane of the display panel can be a square of 150 micrometers. In the actual development of display products, the size of the patterned area can vary with the size of the display panel. The size of the patterned area in this embodiment is merely illustrative and is not intended to be limiting.

[0069] In one exemplary embodiment, the material of the support member 120 may include an elastic metal material, such as a titanium alloy, stainless steel, nickel alloy, or aluminum alloy. The elastic metal material allows the support member 120 to possess superior bending performance and high fatigue resistance and strength. In one example, the material of the support member 120 may include carbon fiber, etc.

[0070] In one exemplary embodiment, such as Figure 4 As shown, the display panel may further include an isolation layer 130 located on the side of the support 120 away from the flexible substrate 110. The orthographic projection of the isolation layer 130 onto the plane of the display panel may include the orthographic projection of the patterned area 121 onto the plane of the display panel. For example, the boundary of the orthographic projection of the isolation layer 130 onto the plane of the display panel may surround the boundary of the orthographic projection of the patterned area 121 onto the plane of the display panel. The isolation layer 130 can prevent water, oxygen, dust, etc., from penetrating the interior of the display panel through the patterned area 121, thereby improving the reliability of the display panel.

[0071] In an exemplary embodiment, the material of the insulating layer 130 may include thermoplastic polyurethanes (TPU) and an adhesive. Using the adhesive, the insulating layer 130 can be integrally bonded to the support member 120. In one example, the thickness of the insulating layer 130 may range from 10 micrometers to 20 micrometers; for example, the thickness of the insulating layer 130 may be 16 micrometers.

[0072] In one exemplary embodiment, such as Figure 4 As shown, the display panel may further include a barrier layer 140, which is configured to prevent contact between the isolation layer 130 and its mating components, thereby avoiding frictional noise. The barrier layer 140 may include a first barrier layer 141 located on the side of the isolation layer 130 away from the support member 120. For example... Figure 4As shown, the first barrier layer 141 may include a first barrier portion 141-1 and a second barrier portion 141-2 spaced apart. In the first direction X, a spacer region 141-3 may be provided between the first barrier portion 141-1 and the second barrier portion 141-2. The spacer region 141-3 is configured for providing an adhesive layer (such as...). Figure 5 , Figure 6 As shown), the adhesive layer is used to bond the isolation layer 130 to the hinge (as shown). Figure 5 , Figure 6 (As shown).

[0073] like Figure 3 As shown, the orthographic projection of the first blocking portion 141-1 and the second blocking portion 141-2 onto the plane where the display panel is located can be a strip shape extending along the second direction Y. For example, the first blocking portion 141-1 and the second blocking portion 141-2 can be symmetrically arranged along the second central axis 402.

[0074] like Figure 3 As shown, the orthographic projection of the spacing region 141-3 onto the plane of the display panel can be a strip shape extending along the second direction Y. In one example, the spacing region 141-3 can be self-symmetrical along the second central axis 402. The size of the spacing region 141-3 along the first direction X can range from 2.0 micrometers to 10 micrometers. In the actual development of display products, the size of the spacing region can vary with the size of the display panel. The size of the spacing region in this embodiment is only illustrative and is not limited thereto.

[0075] In an exemplary embodiment, the first barrier layer 141 may include one or more of the following: an ink layer, a silicone oil layer, or a graphene layer. For example, the first barrier layer 141 may include a fluorine-containing polymer coating. Alternatively, the first barrier layer 141 may include a matte-finished thermoplastic polyurethane elastomer rubber. The first barrier layer 141 has good lubrication properties and can adhere well to the surface of the isolation layer 130, resulting in high connection reliability. The thickness of the first barrier layer 141 can range from 2.0 micrometers to 6.0 micrometers. Taking the first barrier layer 141 as an ink layer as an example, during the fabrication of the display panel, the first barrier layer 141 can be first formed on the isolation layer 130, and then the isolation layer 130 together with the first barrier layer 141 can be bonded to the support member 120. Alternatively, the isolation layer 130 can be first bonded to the support member 120, and then the first barrier layer 141 can be formed on the isolation layer 130. For example, the first barrier layer 141 can be formed by screen printing or pad printing.

[0076] Figure 5 This is a schematic diagram of the foldable display device in a flattened state according to an embodiment of the present disclosure. Figure 6This is a schematic diagram of the foldable display device in a folded state according to an embodiment of this disclosure. Figure 5 , Figure 6 As shown, the display panel may also include a hinge 150. A first barrier layer 141 may be located between the isolation layer 130 and the hinge 150. In actual use, if the first barrier layer is not provided, physical adsorption will form between the isolation layer 130 and the hinge 150 during their contact. When the foldable display device moves from a flattened state to a folded state, or vice versa, relative movement will occur between the isolation layer 130 and the hinge 150. The physical adsorption between the isolation layer 130 and the hinge 150 will continuously stretch and release the molecular chains in the isolation layer, resulting in frictional noise between them. The foldable display device provided in this embodiment, by providing a first barrier layer, can prevent the isolation layer and the hinge from contacting each other, thus avoiding the problem of frictional noise.

[0077] In an exemplary embodiment, the surface energy of the first barrier layer 141 is less than the surface energy of the isolation layer 130, which can prevent physical adsorption between the first barrier layer and the hinge, and can prevent abnormal noise generated between the existing isolation layer and the hinge from being transferred to the first barrier layer and the hinge.

[0078] Figure 7 This is a partial top view of a foldable display device according to an embodiment of the present disclosure. Figure 8 for Figure 7 A cross-sectional view of the section marked BB. Figure 7 , Figure 8 As shown, the display panel may further include a second barrier layer 142, and the second barrier layer 142 is located between the support member 120 and the isolation layer 130. For example, the second barrier layer 142 may be bonded to one side surface of the isolation layer 130. Figure 7As shown, the orthographic projections of the support member 120, the second barrier layer 142, and the isolation layer 130 onto the plane of the display panel can all be rectangles. The orthographic projection of the isolation layer 130 onto the plane of the display panel can lie within the orthographic projection of the support member 120 onto the plane of the display panel, and the orthographic projection of the second barrier layer 142 onto the plane of the display panel can also lie within the orthographic projection of the isolation layer 130 onto the plane of the display panel. For example, the orthographic projection of the second barrier layer 142 onto the plane of the display panel can lie within the orthographic projection of the patterned area 121 onto the plane of the display panel. Both the second barrier layer 142 and the patterned area 121 can be symmetrical along the second central axis 402, and both can be symmetrical along the third central axis 403. For example, the orthographic projection of the isolation layer 130 onto the plane of the display panel may include the orthographic projection of the patterned area 121 onto the plane of the display panel.

[0079] like Figure 7 As shown, the isolation layer 130 has a first edge 13A in its orthographic projection onto the plane of the display panel, and the second barrier layer 142 has a second edge 14A in its orthographic projection onto the plane of the display panel. The first edge 13A surrounds the second edge 14A, and the first edge 13A and the second edge 14A together form a ring. This ring has a ring width W, which can range from 3.0 micrometers to 10 micrometers. For example, the ring width W can be 3.0 micrometers, or the ring width W can be 5.0 micrometers. By limiting the ring width W, the isolation effect of the isolation layer can be guaranteed, improving the display panel's resistance to water, oxygen, and dust. Furthermore, during the folding process of the foldable display device, the local area of ​​the pattern area near the folding center line is in a free state. That is, the local area of ​​the pattern area near the folding center line is not bonded to the isolation layer, which can prevent the pattern area from stretching or compressing the isolation layer during deformation, thereby avoiding abnormal noise. In this embodiment, the folding center line is also the second central axis.

[0080] In an exemplary embodiment, the size of the second barrier layer 142 projected onto the plane of the display panel along the first direction X can range from 3.0 micrometers to 5.0 micrometers. For example, it can be 3.0 micrometers. The thickness of the second barrier layer 142 can range from 8.0 micrometers to 12 micrometers, for example, it can be 10 micrometers. The material of the second barrier layer 142 may include polyethylene terephthalate (PET). When the foldable display device is in a folded state, the deformation of the support member 120 near the second central axis 402 is greater than the deformation of the support member 120 away from the second central axis 402. Therefore, a second barrier layer 142 needs to be provided in the region of the support member 120 near the second central axis 402 to prevent the movement of the support member 120 from causing the isolation layer 130 to move and resulting in folding noise. By limiting the size range of the second barrier layer 142 along the first direction X, folding noise can be avoided, the isolation layer 130 can be guaranteed to have a good isolation effect, and the overall cost of the product can be reduced.

[0081] In one exemplary embodiment, such as Figure 8 As shown, along the side away from the support member 120, the display panel may include a flexible substrate 110, a display structure layer 113, a third adhesive layer 114, a first encapsulation layer 115, a fourth adhesive layer 116, a cover layer 117, a fifth adhesive layer 118, and a second encapsulation layer 119, which are stacked in sequence.

[0082] like Figure 8 As shown, the flexible substrate 110 can be a composite film structure, and may include a flexible composite layer 111 and a first protective layer 112. The flexible composite layer 111 may include a first adhesive layer 111-1, a second adhesive layer 111-2, and a flexible layer 111-3 stacked together. The flexible layer 111-3 may be located between the first adhesive layer 111-1 and the second adhesive layer 111-2. The materials of the first adhesive layer 111-1 and the second adhesive layer 111-2 may include pressure-sensitive adhesive. The material of the flexible layer 111-3 may include polyimide (PI). In this embodiment, the first adhesive layer 111-1 and the second adhesive layer 111-2 can absorb stress and provide cushioning. Designing the flexible substrate 110 as a composite film structure can ensure that the display panel has excellent folding performance and sufficient strength.

[0083] In an exemplary embodiment, the thickness of the flexible layer 111-3 can range from 10 micrometers to 25 micrometers, ensuring that the flexible substrate has a certain strength. For example, the thickness of the flexible layer 111-3 can be 20 micrometers, etc. The thicknesses of the first adhesive layer 111-1 and the second adhesive layer 111-2 can be the same. The thickness of the first adhesive layer 111-1 can range from 10 micrometers to 20 micrometers; for example, the thickness of the first adhesive layer 111-1 can be 20 micrometers. For example, the thickness of the flexible composite layer 111 can be 65 micrometers, wherein the thicknesses of the first adhesive layer 111-1 and the second adhesive layer 111-2 can both be 20 micrometers, and the thickness of the flexible layer 111-3 can be 25 micrometers.

[0084] In an exemplary embodiment, the material of the first protective layer 112 may be polyimide and an adhesive, or polyethylene terephthalate and an adhesive. For example, the thickness of the polyimide may be 50 micrometers, and the thickness of the adhesive may be 10 micrometers.

[0085] In one exemplary embodiment, the display structure layer 113 may include a plurality of pixel units, a plurality of gate lines, and a plurality of data lines. The thickness of the display structure layer 113 may range from 40 micrometers to 50 micrometers; for example, the thickness of the display structure layer 113 may be 43 micrometers.

[0086] In an exemplary embodiment, the material of the first encapsulation layer 115 may include polyethylene terephthalate (PET). The thickness of the first encapsulation layer 115 may range from 20 micrometers to 30 micrometers; for example, the thickness of the first encapsulation layer 115 may be 23 micrometers.

[0087] In one exemplary embodiment, the cover layer 117 may include ultra-thin flexible glass (UTG). The thickness of the cover layer 117 may range from 25 micrometers to 35 micrometers, and for example, the thickness of the cover layer 117 may be 30 micrometers.

[0088] In an exemplary embodiment, the second encapsulation layer 119 may include a black film layer 119-1 and a protective layer 119-2 stacked together. The black film layer 119-1 is configured to allow partial transmission of light emitted from the display structure layer 113. The black film layer 119-1 may include a transparent adhesive layer and a black substance, and the black film layer 119-1 is used to ensure that the display device appears black when in a dark state. The black substance may be carbon black or a black dye, etc. Carbon black may be a quasi-graphite structure material consisting of colloidal particles of approximately spherical shape formed by the incomplete combustion or thermal decomposition of hydrocarbon compounds, existing in aggregate form, and appearing as a pure black powder or granules. The thickness of the black film layer 119-1 may range from 3.0 micrometers to 10 micrometers; for example, the thickness of the black film layer 119-1 may be 5.0 micrometers. The material of the protective layer 119-2 may include polyethylene terephthalate (PET), and the thickness of the protective layer 119-2 may range from 60 micrometers to 70 micrometers. For example, the thickness of the protective layer 119-2 may be 65 micrometers.

[0089] In an exemplary embodiment, the third adhesive layer 114, the fourth adhesive layer 116, and the fifth adhesive layer 118 can all be transparent adhesive layers, and the material of the transparent adhesive layers can include optically clear adhesive (OCA), etc. The thickness range of the third adhesive layer 114, the fourth adhesive layer 116, and the fifth adhesive layer 118 can be the same. The thickness range of the third adhesive layer 114 can be from 45 micrometers to 55 micrometers; for example, the thickness of the third adhesive layer 114 can be 50 micrometers. The thickness of the fourth adhesive layer 116 and the thickness of the fifth adhesive layer 118 can both be equal to the thickness of the third adhesive layer 114.

[0090] In an exemplary embodiment, the first adhesive layer 111-1 has a first elastic modulus K1, the second adhesive layer 111-2 has a second elastic modulus K2, the third adhesive layer 114 has a third elastic modulus K3, the fourth adhesive layer 116 has a fourth elastic modulus K4, and the fifth adhesive layer 118 has a fifth elastic modulus K5, wherein K3 is less than K1, K3 is less than K2, K3 is less than K4, and K3 is less than K5. For example, K3 can be 26 kPa, and the range of K1, K2, K4, and K5 can be from 40 kPa to 50 kPa. In one example, K1 can be equal to K2, and K1 can be 50 kPa. In another example, K4 can be equal to K5, and K4 can be 44 kPa. By setting the relative magnitudes of the first to fifth elastic moduli, the product can obtain better stress and strain parameters during the folding process of the foldable display device, thereby improving the folding quality of the product.

[0091] In this embodiment of the disclosure, by setting a first barrier layer and a second barrier layer, the first barrier layer is located between the isolation layer and the hinge, and the second barrier layer is located between the isolation layer and the pattern area of ​​the support member. The first barrier layer can prevent friction noise between the isolation layer and the hinge, and the second barrier layer can prevent the pattern area from deforming and causing the isolation layer to deform synchronously, thus preventing folding noise.

[0092] The foldable display device in this disclosure can be any foldable product or foldable component with display function, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or navigator. This disclosure does not limit the scope of the foldable display device.

[0093] While the embodiments disclosed in this invention have been described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. It should be noted that the above embodiments or implementation methods are merely exemplary and not restrictive. Therefore, this disclosure is not limited to the content specifically shown and described herein. Various modifications, substitutions, or omissions can be made to the form and details of the implementation without departing from the scope of this disclosure.

Claims

1. A foldable display device, characterized in that, The display panel includes a first non-foldable area, a bending area, and a second non-foldable area arranged sequentially along a first direction, wherein the first non-foldable area, the bending area, and the second non-foldable area all extend along a second direction, and the first direction intersects the second direction; the bending area is configured to switch between a folded state and a flattened state. In a plane perpendicular to the display panel, the display panel includes a flexible substrate and a support member, an isolation layer, and a hinge sequentially located on one side of the flexible substrate; the support member, the isolation layer, and the hinge are all located in the bending area; the support member has a patterned area, the patterned area includes multiple holes, the orthographic projection of the isolation layer onto the plane of the display panel includes the orthographic projection of the patterned area onto the plane of the display panel, and the orthographic projection area of ​​the isolation layer onto the plane of the display panel is larger than the orthographic projection area of ​​the patterned area onto the plane of the display panel; The display panel further includes a barrier layer, which includes a first barrier layer and a second barrier layer. The first barrier layer is disposed between the isolation layer and the hinge, and is used to prevent the isolation layer from contacting the hinge. The second barrier layer is disposed between the support member and the isolation layer, and is used to prevent a portion of the isolation layer from moving with the support member. The second barrier layer prevents the pattern area from deforming and causing the isolation layer to deform. The orthographic projection of the second barrier layer onto the plane of the display panel is located within the orthographic projection of the pattern area onto the plane of the display panel. The orthographic projection of the barrier layer onto the plane of the display panel has a first edge, and the orthographic projection of the second barrier layer onto the plane of the display panel has a second edge. The first edge surrounds the second edge, and the first edge and the second edge together form a ring.

2. The foldable display device as claimed in claim 1, characterized in that, The orthographic projection of the first barrier layer onto the plane where the display panel is located lies within the orthographic projection of the isolation layer onto the plane where the display panel is located.

3. The foldable display device as described in claim 2, characterized in that, The bending region has a second central axis extending along the second direction; the first barrier layer includes a first barrier portion and a second barrier portion arranged at intervals along the first direction, and the first barrier portion and the second barrier portion are symmetrical along the second central axis; the hinge is symmetrical along the second central axis, and the hinge is in contact with both the first barrier portion and the second barrier portion, and the surface energy of the first barrier portion and the surface energy of the second barrier portion are both less than the surface energy of the isolation layer.

4. The foldable display device as claimed in claim 3, characterized in that, The display panel further includes an adhesive layer located between the first barrier portion and the second barrier portion, and the adhesive layer is used to bond the isolation layer and the hinge.

5. The foldable display device as described in any one of claims 1 to 4, characterized in that, The first barrier layer includes at least one of an ink layer, a silicone oil layer, or a graphene layer.

6. The foldable display device as described in any one of claims 1 to 4, characterized in that, The thickness of the first barrier layer ranges from 2.0 micrometers to 6.0 micrometers.

7. The foldable display device as claimed in claim 1, characterized in that, The bending area has a second central axis extending along the second direction; the orthographic projection of the patterned area onto the plane of the display panel is symmetrical along the second central axis, and the orthographic projection of the second barrier layer onto the plane of the display panel is symmetrical along the second central axis.

8. The foldable display device as claimed in claim 7, characterized in that, The ring has a ring width ranging from 3.0 micrometers to 10 micrometers.

9. The foldable display device as claimed in claim 7, characterized in that, The size of the second barrier layer, when projected onto the plane of the display panel along the first direction, ranges from 3.0 micrometers to 5.0 micrometers.

10. The foldable display device as claimed in any one of claims 1 to 4 or 7 to 9, characterized in that, The flexible substrate includes a first adhesive layer, a flexible layer, and a second adhesive layer stacked sequentially, with the first adhesive layer being closer to the support than the second adhesive layer; the flexible layer is made of polyimide, and the thickness of the flexible layer ranges from 10 micrometers to 25 micrometers.

11. The foldable display device as claimed in claim 10, characterized in that, The display panel further includes a third adhesive layer, a fourth adhesive layer, and a fifth adhesive layer, which are sequentially located on the side of the flexible substrate away from the support member; the first adhesive layer has a first elastic modulus, the second adhesive layer has a second elastic modulus, the third adhesive layer has a third elastic modulus, the fourth adhesive layer has a fourth elastic modulus, and the fifth adhesive layer has a fifth elastic modulus; wherein, the first elastic modulus, the second elastic modulus, the fourth elastic modulus, and the fifth elastic modulus are all greater than the third elastic modulus.

12. The foldable display device as claimed in claim 11, characterized in that, The first elastic modulus is equal to the second elastic modulus, and the fourth elastic modulus is equal to the fifth elastic modulus.

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