CN117809521A

CN117809521A - Foldable display device

Info

Publication number: CN117809521A
Application number: CN202410009999.XA
Authority: CN
Inventors: 王吉喆; 蒲乾林; 梁恒镇; 谢志豪; 张英; 闵航; 程金旭; 陆旭; 伏安; 詹峰; 张宜顺
Original assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Priority date: 2024-01-02
Filing date: 2024-01-02
Publication date: 2024-04-02

Abstract

A foldable display device comprises a display panel, wherein the display panel comprises a first non-folding area, a bending area and a second non-folding area which are sequentially arranged along a first direction, the first non-folding area, the bending area and the second non-folding area extend along a second direction, and the first direction and the second direction are intersected; the bending region is configured to be switchable between a folded state and a flattened state; the display panel comprises a flexible substrate, a supporting piece, an isolating layer and a hinge, wherein the supporting piece, the isolating layer and the hinge are sequentially arranged on one side of the flexible substrate; the support piece, the isolation layer and the hinge are all positioned in the bending area; the display panel further comprises a barrier layer, wherein the barrier layer comprises at least one of a first barrier layer and a second barrier layer, and the first barrier layer is arranged between the barrier layer and the hinge and is used for blocking the barrier layer from contacting the hinge; the second separation layer is arranged between the support piece and the separation layer, and is used for separating the movement of part of the separation layer along with the support piece, so that folding abnormal sound can be avoided.

Description

Foldable display device

Technical Field

This disclosure relates to the field of display technology, and more particularly, to a foldable display device.

Background

Organic light emitting diodes (Organic Light Emitting Diode, abbreviated as OLEDs) and Quantum-dot light emitting diodes (qdeds), which are active light emitting display devices, have advantages of self-luminescence, wide viewing angle, high contrast ratio, low power consumption, extremely high reaction speed, thinness, flexibility, low cost, and the like. With the continuous development of Display technology, a Flexible Display device (Flexible Display) using an OLED or a QLED as a light emitting device and a thin film transistor (Thin Film Transistor, abbreviated as TFT) for signal control has become a mainstream product in the current Display field.

At present, the existing foldable display device has the problem of folding abnormal sound.

Disclosure of Invention

The embodiment of the disclosure provides a foldable display device, which can solve the problem of folding abnormal sound existing in the conventional foldable display device.

The embodiment of the disclosure provides a foldable display device, which comprises a display panel, wherein the display panel comprises a first non-folding area, a bending area and a second non-folding area which are sequentially arranged along a first direction, the first non-folding area, the bending area and the second non-folding area extend along a second direction, and the first direction is intersected with the second direction; the bending region is configured to be switchable between a folded state and a flattened state;

in a plane perpendicular to the display panel, the display panel comprises a flexible substrate, and a support piece, an isolation layer and a hinge which are sequentially positioned on one side of the flexible substrate; the support piece, the isolation layer and the hinge are all positioned in the bending area;

the display panel further comprises a barrier layer, wherein the barrier layer comprises at least one of a first barrier layer and a second barrier layer, and the first barrier layer is arranged between the barrier layer and the hinge and used for blocking the barrier layer from contacting the hinge; the second blocking layer is arranged between the supporting piece and the isolating layer and is used for blocking part of the isolating layer from moving along with the supporting piece.

In an exemplary embodiment, the front projection of the spacer layer on the plane of the display panel includes the front projection of the pattern region on the plane of the display panel, and the front projection area of the spacer layer on the plane of the display panel is larger than the front projection area of the pattern region on the plane of the display panel; the orthographic projection of the first barrier layer on the plane of the display panel is positioned in the orthographic projection of the isolation layer on the plane of the display panel.

In an exemplary embodiment, the inflection zone has a second central axis extending in the second direction; the first barrier layer comprises a first barrier part and a second barrier part which are arranged at intervals along the first direction, and the first barrier part and the second barrier part are symmetrical along the second central axis; the hinge is symmetrical along the second central axis, the hinge is in contact with the first blocking portion and the second blocking portion, and the surface energy of the first blocking portion and the surface energy of the second blocking portion are smaller than the surface energy of the isolation layer.

In an exemplary embodiment, the display panel further includes an adhesive layer between the first barrier portion and the second barrier portion, and the adhesive layer is used to adhere the separation layer and the hinge.

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

In an exemplary embodiment, the first barrier layer has a thickness in the range of 2.0 microns to 6.0 microns.

In an exemplary embodiment, the front projection of the spacer layer on the plane of the display panel includes the front projection of the pattern region on the plane of the display panel, and the front projection area of the spacer layer on the plane of the display panel is larger than the front projection area of the pattern region on the plane of the display panel; the orthographic projection of the second barrier layer on the plane of the display panel is positioned in the orthographic projection of the isolation layer on the plane of the display panel.

In an exemplary embodiment, the orthographic projection of the second barrier layer on the plane of the display panel is located within the orthographic projection of the pattern area on the plane of the display panel.

In an exemplary embodiment, the inflection zone has a second central axis extending in the second direction; the orthographic projection of the pattern area on the plane of the display panel is symmetrical along the second central axis, and the orthographic projection of the second barrier layer on the plane of the display panel is symmetrical along the second central axis.

In an exemplary embodiment, the front projection of the isolation layer on the plane of the display panel has a first edge, the front projection of the second isolation layer on 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 shape.

In an exemplary embodiment, the ring has a ring width in the range of 3.0 microns to 10 microns.

In an exemplary embodiment, a dimension of the orthographic projection of the second barrier layer on the plane of the display panel along the first direction ranges from 3.0 micrometers to 5.0 micrometers.

In an exemplary embodiment, the flexible substrate includes a first adhesive layer, a flexible layer, and a second adhesive layer stacked in sequence, and the first adhesive layer is closer to the support than the second adhesive layer; the material of the flexible layer comprises polyimide, and the thickness of the flexible layer ranges from 10 micrometers to 25 micrometers.

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 a 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.

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.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application. Other advantages of the present application may be realized and attained by the structure particularly pointed out in the written description and drawings.

Drawings

The accompanying drawings are included to provide an understanding of the technical aspects of the present application, and are incorporated in and constitute a part of this specification, illustrate the technical aspects of the present application and together with the examples of the present application, and not constitute a limitation of the technical aspects of the present application.

FIG. 1 is a schematic top view of a foldable display device according to an embodiment of the present disclosure;

FIG. 2A is a schematic view of a foldable display device in a folded state;

FIG. 2B is a schematic view of another foldable display device in a folded state;

FIG. 3 is a schematic top view of a portion of a foldable display device according to an embodiment of the present disclosure;

FIG. 4 is a schematic cross-sectional view taken at A-A in FIG. 3;

FIG. 5 is a schematic view of a foldable display device in a flattened state according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of a foldable display device according to an embodiment of the present disclosure in a folded state;

FIG. 7 is a schematic diagram of a foldable display device according to an embodiment of the present disclosure;

fig. 8 is a schematic cross-sectional view of the article of fig. 7 at B-B.

Reference numerals:

100-foldable display device, 101-display panel, 200-first non-folding region, 201-first display region, 202-first peripheral region, 202-1-first upper frame region, 202-2-first lower frame region, 202-3-left frame region, 300-second non-folding region, 301-second display region, 302-second peripheral region, 302-1-second upper frame region, 302-2-second lower frame region, 302-3-right frame region, 400-bending region, 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 glue layer, 111-3-flexible layer, 112-first protective layer, 113-display structure layer, 114-third glue layer, 115-first encapsulation layer, 116-fourth glue layer, 117-cover layer, 118-fifth glue layer, 119-second encapsulation layer, 119-1-black film layer, 119-2-protective layer, 120-support, 121-pattern area, 130-isolation layer, 13A-first edge, 140-isolation layer, 141-first isolation layer, 141-1-first isolation portion, 141-2-second isolation portion, 141-3-spacer region, 142-second isolation layer, 14A-second edge, 143-adhesive layer, 150-hinge.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the present disclosure more apparent, embodiments of the present disclosure will be described in detail hereinafter with reference to the accompanying drawings. Embodiments may be implemented in a number of different forms. One of ordinary skill in the art will readily recognize the fact that the patterns and matters may be changed into one or more forms without departing from the spirit and scope of the present disclosure. Accordingly, the present disclosure should not be construed as being limited to the following description of the embodiments. Embodiments of the present disclosure and features of embodiments may be combined with each other arbitrarily without conflict.

In the drawings, the size of one or more constituent elements, thicknesses of layers or regions may be exaggerated for clarity. Accordingly, one aspect of the present disclosure is not necessarily limited to this dimension, and the shapes and sizes of the various components in the drawings do not reflect actual proportions. Further, the drawings schematically show ideal examples, and one mode of the present disclosure is not limited to the shapes or numerical values shown in the drawings, and the like.

The ordinal terms such as "first," "second," "third," and the like in the present disclosure are provided to avoid intermixing of constituent elements, and are not intended to be limiting in number. The term "plurality" in this disclosure includes two as well as more than two numbers.

In the present disclosure, for convenience, terms such as "middle", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like are used to describe positional relationships of the constituent elements with reference to the drawings, only for convenience in describing the present specification and simplifying the description, and do not indicate or imply that the apparatus or elements to be referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present disclosure. The positional relationship of the constituent elements is appropriately changed according to the direction in which the constituent elements are described. Therefore, the present invention is not limited to the words described in the specification, and may be appropriately replaced according to circumstances.

In this disclosure, the terms "mounted," "connected," and "connected" are to be construed broadly, unless otherwise specifically indicated and defined. For example, it may be a fixed connection, a removable connection, or an integral connection; may be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intermediate members, or may be in communication with the interior of two elements. The meaning of the above terms in the present disclosure can be understood by one of ordinary skill in the art as appropriate.

In this disclosure, a transistor refers to an element including at least three terminals of a gate electrode, a drain electrode, and a source electrode. The transistor has a channel region between a drain electrode (drain electrode terminal, drain region, or drain) and a source electrode (source electrode terminal, source region, or source), and a current can flow through the drain electrode, the channel region, and the source electrode. In the present disclosure, a channel region refers to a region through which current mainly flows.

In the present disclosure, the first electrode may be a drain electrode, the second electrode may be a source electrode, or the first electrode may be a source electrode and the second electrode may be a drain electrode. In the case of using a transistor having opposite polarity, or in the case of a change in the direction of current during circuit operation, the functions of the "source electrode" and the "drain electrode" may be interchanged. Thus, in this disclosure, the "source electrode" and the "drain electrode" may be interchanged.

In this disclosure, "electrically connected" includes a case where constituent elements are connected together by an element having some electric action. The "element having a certain electric action" is not particularly limited as long as it can transmit and receive an electric signal between the constituent elements connected. Examples of the "element having some electric action" include not only an electrode and a wiring but also a switching element such as a transistor, a resistor, an inductor, a capacitor, other elements having one or more functions, and the like.

In the present disclosure, "parallel" refers to a state in which two straight lines form an angle of-10 ° or more and 10 ° or less, and thus, may include a state in which the angle is-5 ° or more and 5 ° or less. Further, "vertical" refers to a state in which an angle formed by two straight lines is 80 ° or more and 100 ° or less, and thus may include a state in which an angle is 85 ° or more and 95 ° or less.

In this disclosure, "film" and "layer" may be interchanged. For example, the "conductive layer" may be sometimes replaced with a "conductive film". In the same manner, the "insulating film" may be replaced with the "insulating layer" in some cases.

The term "about" in this disclosure refers to values that are not strictly limited to the limits, but are allowed to fall within the limits of the process and measurement errors.

In this disclosed embodiment, through setting up the barrier layer, utilize first barrier layer can separate the contact between barrier layer and hinge, can avoid the collapsible display device to take place in the use friction abnormal sound, utilize the second barrier layer can separate the part of barrier layer along with the support piece motion, avoid the barrier layer to be extended or the produced abnormal sound of compression along with the support piece motion promptly, can promote collapsible display device's quality, promote user perception comfort level.

Fig. 1 is a schematic top view of a foldable display device according to an embodiment of the disclosure. As shown in fig. 1, the foldable display device 100 may include a display panel 101. For example, the front projection of the display panel 101 in the plane formed by the first direction X and the second direction Y may be rectangular or the like. The plane of the display panel 101 is parallel to a plane formed by the first direction X and the second direction Y. The display panel 101 may include a inflection region 400 and a non-inflection region. The non-folded regions include at least a first non-folded region 200 and a second non-folded region 300 spaced apart along the first direction X. The first non-folding region 200, the folding region 400, and the second non-folding region 300 may be sequentially arranged in the first direction X. In the embodiment of the present disclosure, the bending region refers to a region where the display panel needs to be bent when bending, and the non-folding region refers to a region where the display panel does not bend or has a smaller degree of bending when bending.

In an exemplary embodiment, as shown in fig. 1, the inflection region 400 may be provided in a bar shape extending along the second direction Y, and the first non-folding region 200 and the second non-folding region 300 may each be provided in a rectangular shape. The inflection zone 400 may have a first central axis 401 extending along a first direction X and a second central axis 402 extending along a second direction Y. By way of example, the first non-folded region 200 and the second non-folded region 300 may be disposed in a symmetrical configuration along both the first central axis 401 and the second central axis 402. By way of example, the display panel 101 may be disposed in a symmetrical structure along the first central axis 401 and the second central axis 402.

In an exemplary embodiment, as shown in fig. 1, the first non-folding area 200 may include a first display area 201 and a first peripheral area 202 located 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 at least one side of the second display area 301.

In an exemplary embodiment, the first display region 201 may include a flexible substrate and a display structure layer disposed on the flexible substrate. The material of the flexible substrate may comprise Polyimide (PI), polyethylene terephthalate (PET), or a Polyimide (PET) or a Polyimide (PI) at the surfaceMaterials such as polymer soft films, and materials for flexible substrates may include silicon nitride (SiN _x ) Or silicon oxide (SiO) _x ) And inorganic matters are used for improving the water-oxygen resistance of the flexible substrate. The second display area 301 may be designed with reference to the first display area 201, and will not be further described herein.

In an exemplary embodiment, the display structure layer may include a plurality of pixel units (the pixel units include a plurality of sub-pixels), a plurality of gate lines, and a plurality of data lines. The plurality of data lines may extend in the second direction Y, and the plurality of gate lines may extend in the first direction X. Orthographic projections of the plurality of gate lines and the plurality of data lines on the flexible substrate may cross to form a plurality of sub-pixel regions. One subpixel is disposed in one subpixel region. The plurality of data lines are electrically connected to the plurality of sub-pixels, and the plurality of data lines are configured to supply data signals to the plurality of sub-pixels. The plurality of gate lines are electrically connected to the plurality of sub-pixels, and the plurality of gate lines are configured to supply gate driving signals to the plurality of sub-pixels.

In an exemplary embodiment, one pixel unit may include at least three sub-pixels, and the three sub-pixels may be red, green, and blue sub-pixels, respectively. The three sub-pixels may be arranged in a horizontal parallel, vertical parallel or delta manner, which is not limited by the embodiments of the present disclosure. For example, one 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 in a horizontal parallel, vertical parallel or square manner.

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 a plurality of transistors and at least one capacitor. For example, the pixel circuit may be a 3T1C, 4T1C, 5T2C, 6T1C, 7T1C, or 8T1C structure. Wherein, T in the circuit structure refers to a thin film transistor, C refers to a capacitor, the number in front of T represents the number of the thin film transistors in the circuit, and the number in front of C represents the number of the capacitors in the circuit.

In an exemplary embodiment, the plurality of transistors in the pixel circuit may be P-type transistors or may be N-type transistors. The same type of transistor is adopted in the pixel circuit, so that the process flow can be simplified, the process difficulty of the display panel is reduced, and the yield of products is improved. In other examples, the plurality of transistors in the pixel circuit may include a P-type transistor and an N-type transistor.

In an exemplary embodiment, the plurality of transistors in the pixel circuit may employ a low temperature polysilicon thin film transistor, or may employ an oxide thin film transistor, or may employ a low temperature polysilicon thin film transistor and an oxide thin film transistor. The active layer of the low temperature polysilicon thin film transistor adopts low temperature polysilicon (LTPS, low Temperature Poly-Silicon), and the active layer of the Oxide thin film transistor adopts Oxide semiconductor (Oxide). The low-temperature polycrystalline silicon thin film transistor has the advantages of high mobility, quick charge and the like, the Oxide thin film transistor has the advantages of low leakage current and the like, and the low-temperature polycrystalline silicon thin film transistor and the Oxide thin film transistor are integrated on one display panel, namely an LTPS+oxide (LTPO) display panel, so that the advantages of the low-temperature polycrystalline silicon thin film transistor and the Oxide thin film transistor can be utilized, low-frequency driving can be realized, the power consumption of a display device can be reduced, and the display quality can be improved.

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

In an exemplary embodiment, the first peripheral region 202 may include a binding circuit connecting the signal line to an external driving device. For example, the binding circuit may be electrically connected to an external driving device via a flip chip film. The first peripheral region 202 may further include a gate driving circuit and a second power line VSS transmitting voltage signals to the plurality of subpixels. The second peripheral region 302 may be designed with reference to the first peripheral region 202, and will not be described in detail herein.

In an exemplary embodiment, as shown in FIG. 1, the first peripheral region 202 may include a first upper border region 202-1, a first lower border region 202-2, and a left border region 202-3 connected. There is a space between the first upper border region 202-1 and the first lower border region 202-2 along the second direction Y, and the left border region 202-3 is located between the first upper border region 202-1 and the first lower border region 202-2. A first end of the first upper frame region 202-1 may be connected to a first end of the left frame region 202-3, and a second end of the first upper frame region 202-1 may extend in the first direction X. A first end of the first lower frame region 202-2 may be connected to a second end of the left frame region 202-3, and a second end of the first lower frame region 202-2 may extend in the first direction X. The left bezel area 202-3 may extend in the second direction Y. In an example, the binding circuit may be located in the first lower bezel area 202-2.

In an exemplary embodiment, as shown in FIG. 1, the second peripheral region 302 may include a second upper border region 302-1, a second lower border region 302-2, and a right border region 302-3 connected. A space in the second direction Y exists between the second upper frame region 302-1 and the second lower frame region 302-2, and the right frame region 302-3 is located between the second upper frame region 302-1 and the second lower frame region 302-2. A first end of the second upper frame region 302-1 may be connected with a first end of the right frame region 302-3, and a second end of the second upper frame region 302-1 may extend in an opposite direction of the first direction X. A second end of the second upper rim area 302-1 may be connected to a second end of the first upper rim area 202-1. A first end of the second lower frame region 302-2 may be connected with a second end of the right frame region 302-3, and a second end of the second lower frame region 302-2 may extend in a direction opposite to the first direction X. A second end of the second lower rim region 302-2 may be connected to a second end of the first lower rim region 202-2. The right bezel area 302-3 may extend in the second direction Y. In an example, the binding circuit may be located in the second lower bezel area 302-2. Alternatively, portions of the binding circuit may be located in the first lower frame region 202-2 and other portions of the binding circuit may be located in the second lower frame region 302-2.

In an exemplary embodiment, the display panel 101 may include a plurality of bending regions 400. The number, division and positional relationship of the bending regions and the non-folding regions may be determined according to actual needs, and the embodiments of the present disclosure are not limited herein. In the exemplary embodiment of the present disclosure, the display panel 101 includes three parts: the bending region 400 and the first non-folding region 200 and the second non-folding region 300 respectively disposed at both sides of the bending region 400 are exemplified for explanation of the technical scheme.

Fig. 2A is a schematic view of a foldable display device in a folded state, and fig. 2B is a schematic view of another foldable display device in a folded state. As shown in fig. 2A, the foldable display device 100 may achieve an inwardly folded state, and the folding angle may range from 0 degrees to 180 degrees. As shown in fig. 2B, the foldable display device 100 may achieve an outward folded state, and the folding angle may range from 180 degrees to 360 degrees. In the embodiment of the present disclosure, the foldable angle range of the foldable display device 100 is not limited.

Fig. 3 is a schematic partial top view of a foldable display device according to an embodiment of the present disclosure, and fig. 4 is a schematic cross-sectional view of the foldable display device denoted by A-A in fig. 3. In the embodiment of the present disclosure, the plane perpendicular to the display panel may be a plane formed by the first direction X and the third direction Z, or a plane formed by the second direction Y and the third direction Z, and in the embodiment of the present disclosure, the third direction Z may also be referred to as a thickness direction of the display panel. In the embodiment of the present disclosure, the first direction X, the second direction Y, and the third direction Z may be perpendicular to each other. As shown in fig. 3 and 4, the display panel may further include a support 120 at one side of the flexible substrate 110. The support 120 is configured to be switchable between a bent state and an initial state with the display panel 101. The foldable display device is in a folded state, the supporting member 120 may be bent along with the display panel 101, and the supporting member 120 is in a bent state. The support 120 may be restored from the folded state to the original state in the unfolded state of the foldable display device. In the embodiment of the disclosure, the angle between the first non-folding area and the second non-folding area in the flattened state of the foldable display device is 180 degrees. The display panel is in a folded state, i.e. the foldable display device is in a folded state. The display panel is in a flattened state, and the foldable display device is in a flattened state.

As shown in fig. 4, the support 120 may be symmetrical to itself along the third central axis 403. The third central axis 403 may extend through the center of the inflection zone 400 and along a third direction Z. The front projection of the supporting member 120 on the plane of the display panel may include the front projection of the bending region 400 on the plane of the display panel. In the embodiment of the disclosure, the plane in which the display panel is located is a plane formed by the first direction X and the second direction Y. The support 120 has a pattern area 121, and the pattern area 121 may include a plurality of holes, which may be through holes or blind holes, or a part of the holes may be through holes and the rest may be blind holes. The pore diameters of the plurality of pores may be the same or different. In an example, the holes may include any one of round holes, elliptical holes, rectangular holes, pentagonal holes, and the like.

As shown in fig. 4, the front projection of the pattern area 121 on the plane of the display panel may be located within the front projection of the bending area 400 on the plane of the display panel, and for example, the edge of the front projection of the pattern area 121 on the plane of the display panel may coincide with the edge of the front projection of the bending area 400 on the plane of the display panel.

In an exemplary embodiment, the size of the orthographic projection of the pattern area 121 on the plane of the display panel along the first direction may range from 130 micrometers to 160 micrometers, and the size of the orthographic projection of the pattern area 121 on the plane of the display panel along the second direction may range from 130 micrometers to 160 micrometers, and for example, the orthographic projection of the pattern area 121 on the plane of the display panel may be a square of 150 micrometers. In practical development of display products, the size of the pattern area may vary with the size of the display panel, and the size of the pattern area in the embodiments of the present disclosure is merely illustrative and not limiting.

In an exemplary embodiment, the material of the support 120 may include an elastic metal material, such as a titanium alloy or a stainless steel or a nickel alloy or an aluminum alloy, etc., which may provide the support 120 with superior bending performance and high fatigue resistance and strength. In an example, the material of the support 120 may include carbon fiber or the like.

In an exemplary embodiment, as shown in fig. 4, the display panel may further include a spacer layer 130 at a side of the support 120 remote from the flexible substrate 110. The orthographic projection of the spacer 130 on the plane of the display panel may include orthographic projection of the pattern area 121 on the plane of the display panel. For example, the front projection boundary of the spacer layer 130 on the plane of the display panel may surround the front projection boundary of the pattern region 121 on the plane of the display panel. The barrier layer 130 may prevent water, oxygen, dust, etc. from invading the inside of the display panel through the pattern region 121, and may improve the reliability of the display panel using the barrier layer.

In an exemplary embodiment, the material of the isolation layer 130 may include thermoplastic polyurethane elastomer rubber (Thermoplastic polyurethanes, abbreviated as TPU) and a rubber material. The isolation layer 130 may be integrally adhered to the support 120 by means of a glue. In one example, the thickness of the spacer layer 130 may range from 10 microns to 20 microns, and, illustratively, the thickness of the spacer layer 130 may be 16 microns.

In an exemplary embodiment, as shown in fig. 4, the display panel may further include a barrier layer 140, and the barrier layer 140 is configured to block contact between the barrier layer 130 and a mating part thereof, thereby avoiding friction noise. The barrier layer 140 may include a first barrier layer 141 on a side of the barrier layer 130 remote from the support 120. As shown in fig. 4, the first barrier layer 141 may include first and second barrier portions 141-1 and 141-2 disposed at intervals. In the first direction X, a spacing region 141-3 may be provided between the first barrier 141-1 and the second barrier 141-2. The spacer 141-3 is configured to provide an adhesive layer (as shown in fig. 5 and 6) for adhering the separation layer 130 to the hinge (as shown in fig. 5 and 6).

As shown in fig. 3, the front projection of the first barrier 141-1 and the second barrier 141-2 on the plane of the display panel may have a bar shape extending along the second direction Y. For example, the first blocking portion 141-1 and the second blocking portion 141-2 may be symmetrically disposed along the second central axis 402.

As shown in fig. 3, the front projection of the spacer 141-3 on the plane of the display panel may have a stripe shape extending along the second direction Y. In one example, the spacer region 141-3 may be itself symmetrical along the second central axis 402. The size of the spacer 141-3 in the first direction X may range from 2.0 micrometers to 10 micrometers. In practical development of display products, the size of the spacer may vary with the size of the display panel, and the size of the spacer in embodiments of the present disclosure is merely illustrative and not limiting.

In an exemplary embodiment, the first barrier layer 141 may include one or more of an ink layer, a silicone oil layer, a graphene layer, or the like. By way of example, the first barrier layer 141 may include a fluorine-containing high molecular polymer coating. Alternatively, the first barrier layer 141 may include a matte-treated thermoplastic polyurethane elastomer rubber. The first barrier layer 141 has a good lubrication effect, can be well adhered to the surface of the barrier layer 130, and has high connection reliability. The thickness of the first barrier layer 141 may range from 2.0 micrometers to 6.0 micrometers. Taking the first barrier layer 141 as an ink layer as an example, in the process of manufacturing the display panel, the first barrier layer 141 may be molded on the barrier layer 130, and then the barrier layer 130 and the first barrier layer 141 may be adhered to the support 120. Alternatively, the barrier layer 130 may be adhered to the support 120 first, and then the first barrier layer 141 may be molded on the barrier layer 130. The first barrier layer 141 may be formed by screen printing (silk screen process printing), pad printing, or the like.

Fig. 5 is a schematic view of a foldable display device in a flattened state according to an embodiment of the present disclosure, and fig. 6 is a schematic view of a foldable display device in a folded state according to an embodiment of the present disclosure. As shown in fig. 5 and 6, the display panel may further include a hinge 150. The first barrier layer 141 may be located between the barrier layer 130 and the hinge 150. In actual use, if the first barrier layer is not provided, physical adsorption may be formed during the contact of the barrier layer 130 with the hinge 150, since the barrier layer 130 is in contact with both the hinge 150. When the foldable display device moves from the flattened state to the folded state, or when the foldable display device moves from the folded state to the flattened state, the isolation layer 130 and the hinge 150 move relatively, and the physical adsorption formed between the isolation layer 130 and the hinge 150 can continuously stretch and release molecular chains in the isolation layer, so that friction abnormal sound can be generated between the isolation layer 130 and the hinge 150. According to the foldable display device provided by the embodiment of the disclosure, the first barrier layer is arranged, so that the contact between the barrier layer and the hinge can be avoided, and the problem of friction abnormal sound can be avoided.

In an exemplary embodiment, the surface energy of the first barrier layer 141 is smaller than the surface energy of the barrier layer 130, so that physical adsorption between the first barrier layer and the hinge can be avoided, and abnormal noise generated between the existing barrier layer and the hinge can be prevented from being transferred to the first barrier layer and the hinge.

Fig. 7 is a schematic diagram of a foldable display device according to an embodiment of the disclosure, and fig. 8 is a schematic diagram of a cross section at B-B in fig. 7. As shown in fig. 7 and 8, the display panel may further include a second barrier layer 142, and the second barrier layer 142 is located between the support 120 and the isolation layer 130. For example, the second barrier layer 142 may be adhered to one side surface of the barrier layer 130. As shown in fig. 7, the front projection of the supporting member 120 on the plane of the display panel, the front projection of the second barrier layer 142 on the plane of the display panel, and the front projection of the barrier layer 130 on the plane of the display panel may be rectangular. The front projection of the spacer layer 130 on the plane of the display panel may be located within the front projection of the support 120 on the plane of the display panel, and the front projection of the second barrier layer 142 on the plane of the display panel may be located within the front projection of the spacer layer 130 on the plane of the display panel. For example, the front projection of the second barrier layer 142 on the plane of the display panel may be located within the front projection of the pattern area 121 on the plane of the display panel. The second barrier layer 142 and the pattern region 121 may be symmetrical along the second central axis 402, and the second barrier layer 142 and the pattern region 121 may be symmetrical along the third central axis 403. For example, the orthographic projection of the spacer layer 130 on the plane of the display panel may include the orthographic projection of the pattern region 121 on the plane of the display panel.

As shown in fig. 7, the front projection of the spacer layer 130 on the plane of the display panel has a first edge 13A, the front projection of the second spacer layer 142 on the plane of the display panel has a second edge 14A, the first edge 13A surrounds the second edge 14A, and the first edge 13A and the second edge 14A together form a ring shape having a ring width W, and the ring width W may range from 3.0 micrometers to 10 micrometers. For example, the ring width W may be 3.0 microns, or the ring width W may be 5.0 microns. Through limiting the ring width W, the isolation effect of the isolation layer can be ensured, the capability of the display panel against water, oxygen and dust is improved, and in the folding process of the foldable display device, the local area of the pattern area, which is close to the folding center line, is in a free state, that is, the local area of the pattern area, which is close to the folding center line, is not bonded with the isolation layer, so that the stretching or compression of the isolation layer in the deformation process of the pattern area can be avoided, and abnormal noise can be avoided. In the presently disclosed embodiments, the fold centerline is also referred to as the second central axis.

In an exemplary embodiment, the size of the orthographic projection of the second barrier layer 142 on the plane of the display panel along the first direction X may range from 3.0 micrometers to 5.0 micrometers. For example, it may be 3.0 microns. The thickness of the second barrier layer 142 may range from 8.0 microns to 12 microns, and may be 10 microns, for example. The material of the second barrier layer 142 may include polyethylene terephthalate (PET). When the foldable display device is in the folded state, the deformation of the supporting member 120 near the second central axis 402 is greater than the deformation of the supporting member 120 far away from the second central axis 402, so that the second barrier layer 142 needs to be disposed on the supporting member 120 near the second central axis 402 to prevent the supporting member 120 from moving to drive the barrier layer 130 to move and generate folding abnormal sound. By defining the size range of the second barrier layer 142 along the first direction X, folding abnormal noise can be avoided, the barrier layer 130 can be ensured to have a good barrier effect, and the overall cost of the product can be reduced.

In an exemplary embodiment, as shown in fig. 8, along a side away from the support 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 plate layer 117, a fifth adhesive layer 118, and a second encapsulation layer 119, which are sequentially stacked.

As shown in fig. 8, the flexible substrate 110 may be a composite film layer structure, and the flexible substrate 110 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 that are stacked. The flexible layer 111-3 may be positioned between the first adhesive layer 111-1 and the second adhesive layer 111-2. The material of the first adhesive layer 111-1 and the second adhesive layer 111-2 may include a pressure sensitive adhesive (pressure sensitive adhesive). The material of the flexible layer 111-3 may include Polyimide (PI). In the embodiment of the present disclosure, the first adhesive layer 111-1 and the second adhesive layer 111-2 may function to absorb stress and buffer. The flexible substrate 110 is designed into a composite film structure, which can ensure that the display panel has excellent folding performance and enough strength.

In an exemplary embodiment, the thickness of the flexible layer 111-3 may range from 10 micrometers to 25 micrometers, which may ensure that the flexible substrate has a certain strength. By way of example, the thickness of the flexible layer 111-3 may be 20 microns or the like. The thickness of the first adhesive layer 111-1 and the second adhesive layer 111-2 may be the same, and the thickness of the first adhesive layer 111-1 may range from 10 micrometers to 20 micrometers, and for example, the thickness of the first adhesive layer 111-1 may be 20 micrometers. By way of example, the thickness of the flexible composite layer 111 may be 65 microns, wherein the thickness of the first adhesive layer 111-1 and the thickness of the second adhesive layer 111-2 may both be 20 microns, and the thickness of the flexible layer 111-3 may be 25 microns.

In an exemplary embodiment, the material of the first protective layer 112 may be polyimide and a glue material, or polyethylene terephthalate and a glue material. For example, the polyimide may have a thickness of 50 microns and the glue may have a thickness of 10 microns.

In an exemplary embodiment, the display structure layer 113 may include a plurality of pixel cells, 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, and the thickness of the display structure layer 113 may be 43 micrometers, as an example.

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, and the thickness of the first encapsulation layer 115 may be 23 micrometers, as an example.

In an exemplary embodiment, the cover sheet layer 117 may include Ultra Thin flexible Glass (UTG). The thickness of the cover sheet layer 117 may range from 25 microns to 35 microns, and an exemplary thickness of the cover sheet layer 117 may be 30 microns.

In an exemplary embodiment, the second encapsulation layer 119 may include a black film layer 119-1 and a protective layer 119-2 that are stacked. The black film layer 119-1 is provided to be transparent to a portion of light emitted from the display structure layer 113. The black film 119-1 may include a transparent adhesive layer and a black material, and the black film 119-1 may be used to ensure that the display device is black when in a dark state. The black material may be carbon black or a black dye or the like. Carbon black may be a quasi-graphite structure material of colloidal particles, which is approximately spherical, formed by incomplete combustion or thermal cracking of hydrocarbon compounds, and exists in the form of aggregates, in the form of powder or granules, which are apparent in pure black. The thickness of the black film layer 119-1 may range from 3.0 micrometers to 10 micrometers, and the thickness of the black film layer 119-1 may be 5.0 micrometers, as an example. The material of the overcoat layer 119-2 may include polyethylene terephthalate (PET), and the thickness of the overcoat layer 119-2 may range from 60 micrometers to 70 micrometers, and, illustratively, the thickness of the overcoat layer 119-2 may be 65 micrometers.

In an exemplary embodiment, the third adhesive layer 114, the fourth adhesive layer 116, and the fifth adhesive layer 118 may be transparent adhesive layers, and the material of the transparent adhesive layers may include optical adhesive (Optically Clear Adhesive, OCA for short), and the like. The thickness of the third glue layer 114, the fourth glue layer 116 and the fifth glue layer 118 may be the same, the thickness of the third glue layer 114 may be in the range of 45 micrometers to 55 micrometers, and the thickness of the third glue layer 114 may be 50 micrometers, for example. The thickness of the fourth adhesive layer 116 and the thickness of the fifth adhesive layer 118 may be equal to the thickness of the third adhesive layer 114.

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 and K3 is less than K2 and K3 is less than K4 and K3 is less than K5, and exemplary K3 may be 26 kilopascals, and K1, K2, K4, and K5 may range from 40 kilopascals to 50 kilopascals. In one example, K1 may be equal to K2 and K1 may be 50 kilopascals. In one example, K4 may be equal to K5 and K4 may be 44 kilopascals. By setting the relative magnitude relation between the first elastic modulus and the fifth elastic modulus, in the folding process of the foldable display device, the product obtains better stress parameters and strain parameters, and the folding quality of the product can be improved.

In the embodiment of the disclosure, through setting up first barrier layer and second barrier layer, first barrier layer is located between barrier layer and the hinge, and the second barrier layer is located between the pattern area of barrier layer and support piece, and first barrier layer can prevent to produce friction abnormal sound between barrier layer and the hinge, and the second barrier layer can prevent pattern area deformation and drive the barrier layer synchronous deformation, can prevent folding abnormal sound.

The foldable display device in the embodiment of the present disclosure may be: any foldable product or foldable component having a display function, such as a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, and a navigator, is not limited herein.

Although the embodiments of the present invention are described above, the embodiments are only used for facilitating understanding of the present invention, and are not intended to limit the present invention. It should be noted that the above-described examples or implementations are merely exemplary and not limiting. Accordingly, the present disclosure is not limited to what has been particularly shown and described herein. Various modifications, substitutions, or omissions may be made in the form and details of the implementations without departing from the scope of the disclosure.

Claims

1. The foldable display device is characterized by comprising a display panel, wherein the display panel comprises a first non-folding area, a bending area and a second non-folding area which are sequentially arranged along a first direction, the first non-folding area, the bending area and the second non-folding area extend along a second direction, and the first direction is intersected with the second direction; the bending region is configured to be switchable between a folded state and a flattened state;

2. The foldable display device of claim 1, wherein the support has a pattern area, wherein the orthographic projection of the spacer layer on the plane of the display panel includes an orthographic projection of the pattern area on the plane of the display panel, and wherein an orthographic projection area of the spacer layer on the plane of the display panel is larger than an orthographic projection area of the pattern area on the plane of the display panel; the orthographic projection of the first barrier layer on the plane of the display panel is positioned in the orthographic projection of the isolation layer on the plane of the display panel.

3. The foldable display device of claim 2, wherein the bending region has a second central axis extending along the second direction; the first barrier layer comprises a first barrier part and a second barrier part which are arranged at intervals along the first direction, and the first barrier part and the second barrier part are symmetrical along the second central axis; the hinge is symmetrical along the second central axis, the hinge is in contact with the first blocking portion and the second blocking portion, and the surface energy of the first blocking portion and the surface energy of the second blocking portion are smaller than the surface energy of the isolation layer.

4. The foldable display device of claim 3, wherein the display panel further comprises an adhesive layer between the first barrier portion and the second barrier portion, and the adhesive layer is for adhering the spacer layer and the hinge.

5. The foldable display device of any one of claims 1 to 4, wherein the first barrier layer comprises at least one of an ink layer, a silicone oil layer, or a graphene layer.

6. The foldable display device of any one of claims 1 to 4, wherein the first barrier layer has a thickness in the range of 2.0 microns to 6.0 microns.

7. The foldable display device of claim 1, wherein the support has a pattern area, wherein the orthographic projection of the spacer layer on the plane of the display panel includes an orthographic projection of the pattern area on the plane of the display panel, and wherein an orthographic projection area of the spacer layer on the plane of the display panel is larger than an orthographic projection area of the pattern area on the plane of the display panel; the orthographic projection of the second barrier layer on the plane of the display panel is positioned in the orthographic projection of the isolation layer on the plane of the display panel.

8. The foldable display device of claim 7, wherein an orthographic projection of the second barrier layer on the plane of the display panel is within an orthographic projection of the pattern area on the plane of the display panel.

9. The foldable display device of claim 8, wherein the bending region has a second central axis extending along the second direction; the orthographic projection of the pattern area on the plane of the display panel is symmetrical along the second central axis, and the orthographic projection of the second barrier layer on the plane of the display panel is symmetrical along the second central axis.

10. The foldable display device of claim 9, wherein the front projection of the spacer layer in the plane of the display panel has a first edge, the front projection of the second spacer layer in 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.

11. The foldable display device of claim 10, wherein the ring has a ring width in a range of 3.0 microns to 10 microns.

12. The foldable display device of claim 9, wherein a dimension of the second barrier layer in the first direction of an orthographic projection of the plane of the display panel is in a range of 3.0 micrometers to 5.0 micrometers.

13. The foldable display device of any one of claims 1 to 4 or 7 to 12, wherein the flexible substrate comprises a first adhesive layer, a flexible layer, and a second adhesive layer, which are sequentially stacked, and wherein the first adhesive layer is closer to the support than the second adhesive layer; the material of the flexible layer comprises polyimide, and the thickness of the flexible layer ranges from 10 micrometers to 25 micrometers.

14. The foldable display device of claim 13, wherein the display panel further comprises a third glue layer, a fourth glue layer, and a fifth glue layer positioned in sequence on a side of the flexible substrate remote from the support; 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.

15. The foldable display device of claim 14, wherein the first modulus of elasticity is equal to the second modulus of elasticity and the fourth modulus of elasticity is equal to the fifth modulus of elasticity.