CN115547184B

CN115547184B - Flexible supporting layer, flexible display module and flexible display device

Info

Publication number: CN115547184B
Application number: CN202210422637.4A
Authority: CN
Inventors: 熊源; 张玉军; 袁高
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2022-04-21
Filing date: 2022-04-21
Publication date: 2023-06-13
Anticipated expiration: 2042-04-21
Also published as: CN115547184A

Abstract

The application discloses a flexible supporting layer, flexible display module assembly and flexible display device belongs to and shows technical field. The flexible support layer includes a bending portion and a non-bending portion. The flexible supporting layer is made of foam materials, and the porosity of the bending part is larger than that of the non-bending part, so that the bending part is easy to bend. The foam material is used as the flexible supporting layer, so that the weight of the flexible supporting layer can be reduced, and the portability of the flexible display device applied by the flexible supporting layer is facilitated. Because of the small pore size of the pores of the foam, the pore portion of the bend has no clear boundary with the non-pore portion, which is advantageous for stress dispersion. In addition, since the pores of the foam material have small pore diameters, when the flexible support layer is applied to a flexible display device, the optical cement attached to the flexible support layer is difficult to be forced to overflow into the pores, so that the imprint generated by the accumulation of the optical cement in the pores can be prevented to a large extent.

Description

Flexible supporting layer, flexible display module and flexible display device

Technical Field

The application relates to the technical field of display, in particular to a flexible supporting layer, a flexible display module and a flexible display device.

Background

With the continuous development of display technology, flexible display devices have become a development trend of electronic products. The flexible display device has smaller volume when in a folded state, and is convenient for users to carry; when in a flattened state, the display screen has a larger display area and a better display effect. The flexible display device generally includes a flexible support layer and a flexible display panel on the flexible support layer, and the flexible support layer and the flexible display panel are bonded by an optical adhesive.

In the related art, the flexible support layer is typically a metal plate material, such as a titanium plate material. However, the flexible supporting layer formed of the metal plate material has a large weight, which is disadvantageous for portability of the flexible display device.

Disclosure of Invention

The application provides a flexible supporting layer, flexible display module and flexible display device, can alleviate the weight of flexible supporting layer to be favorable to flexible display device's portability. The technical scheme is as follows:

in a first aspect, a flexible support layer is provided for supporting a display panel. The flexible supporting layer comprises N+1 non-bending parts and N bending parts. The ith bending part in the N bending parts is connected between the ith non-bending part in the N+1 non-bending parts and the ith+1 non-bending part. Wherein N is a positive integer, and i is a positive integer less than or equal to N. That is, each bending portion is connected between two non-bending portions, and only one bending portion is connected between two non-bending portions. Thus, after the flexible supporting layer is applied to the flexible display device, when the flexible display device is folded, the bending part of the flexible supporting layer is in a bending state; when the flexible display device is completely unfolded, the bending part of the flexible supporting layer is in a flat-laid state.

The flexible support layer is made of foam material. The foam material is also called a porous material, and is a material with a certain number of pores and a network structure. The foam material can be foamed metal or polymer foam material. The metal foam may be, for example, titanium foam, silver foam, nickel foam, copper foam, or the like. In the flexible support layer provided by the application, the porosity of the bending part is larger than that of the non-bending part. Porosity refers to the ratio of the volume of all pores in the foam to the total volume of the foam. That is, in the flexible support layer provided herein, the ratio of the volume of all the pores of the bent portion to the total volume of the bent portion is greater than the ratio of the volume of all the pores of the non-bent portion to the total volume of the non-bent portion. Therefore, the elastic modulus of the bending part is smaller than that of the non-bending part, so that the bending part of the flexible supporting layer is easier to bend.

In this application, the flexible support layer includes a bend and a non-bend. The flexible supporting layer is made of foam materials, and the porosity of the bending part is larger than that of the non-bending part, so that the bending part is easy to bend. The foam material is used as the flexible supporting layer, so that the weight of the flexible supporting layer can be reduced, and the portability of the flexible display device applied by the flexible supporting layer is facilitated. Because of the small pore size of the pores of the foam, the pore portion of the bend has no clear boundary with the non-pore portion, which is advantageous for stress dispersion. In addition, since the pores of the foam material have small pore diameters, when the flexible support layer is applied to a flexible display device, the optical cement attached to the flexible support layer is difficult to be forced to overflow into the pores, so that the imprint generated by the accumulation of the optical cement in the pores can be prevented to a large extent.

In some embodiments, the ith bend has a central axis. The ith bending part is symmetrical about the central axis of the ith bending part.

In some embodiments, the porosity of the ith bend decreases linearly or stepwise in the first direction, or/and in the second direction. The first direction refers to a direction from the central axis of the ith bending part to the ith non-bending part. The second direction refers to a direction from the central axis of the ith bending part to the (i+1) th non-bending part. In some particular embodiments, the porosity of the portion of the ith bend between the ith non-bend and the central axis of the ith bend decreases linearly or in steps along the first direction, and the porosity of the portion of the ith bend between the central axis of the ith bend and the (i+1) th non-bend decreases linearly or in steps along the second direction. Therefore, the part with the linearly reduced porosity or the echelon reduced porosity of the bending part forms a transition zone, and when the bending part of the flexible supporting layer is bent, the elastic modulus of the bending part can gradually become larger along the first direction and the second direction, so that the safety of the flexible supporting layer in the bending process can be improved. Meanwhile, as the part with linearly reduced porosity or gradient reduced porosity of the bending part forms a transition area, no obvious boundary exists between the bending part and the non-bending part, and thus, the phenomenon that an impression is generated between the bending part and the non-bending part after the flexible supporting layer is bent for many times can be avoided.

In some embodiments, the porosity of the flexible support layer is the same at locations symmetrical about the central axis of the ith bend. Therefore, the flexible supporting layer can provide symmetrical and balanced supporting force for the display panel, and the supporting capacity of the flexible supporting layer is improved.

In some embodiments, the ith bend has opposing first and second surfaces. The first surface is used for supporting the display panel. In the third direction, the porosity of the ith bend decreases linearly or stepwise. Wherein the third direction is a direction from the second surface to the first surface. That is, the portion of the ith bent portion near the first surface has a smaller porosity, thereby making the ith bent portion more supportive of the display panel.

In some embodiments, the ith bend has a recess. The recess may be a patterned structure formed at the i-th bent portion. Thus, the elastic modulus of the ith bending portion can be reduced, thereby making the bending portion more easily bendable.

In some embodiments, the ith bend has opposing first and second surfaces. The first surface is used for supporting the display panel. The concave part of the ith bending part is positioned on the second surface. In some embodiments, the recess of the ith bend in the third direction extends through the ith bend or does not extend through the ith bend. When the flexible supporting layer is applied to the flexible display device, the optical adhesive attached to the flexible supporting layer can be prevented from overflowing into the concave part under the stress, so that the optical adhesive can be prevented from accumulating in the concave part to generate an impression.

In some embodiments, the concentration of the depressions of the ith bend decreases linearly or stepwise in the first direction, or/and in the second direction. In some embodiments, the concentration of the depressions is linearly reduced or stepped in a first direction at a portion of the ith bend between the ith non-bend and the central axis of the ith bend, and is linearly reduced or stepped in a second direction at a portion of the ith bend between the central axis of the ith bend and the (i+1) th non-bend. Therefore, a transition area can be formed at the part, close to the non-bending part, of the ith bending part, and when the bending part of the flexible supporting layer is bent, the elastic modulus of the bending part can be gradually increased along the first direction and the second direction, so that the safety of the flexible supporting layer in the bending process can be improved. Meanwhile, as the transition area is formed by the part with linearly reduced or echelon reduced concentration of the concave part of the bending part, no obvious boundary exists between the bending part and the non-bending part, and thus, the phenomenon that the flexible supporting layer is stamped between the bending part and the non-bending part after being bent for many times can be avoided.

In some embodiments, the ith bend also has opposing third and fourth surfaces, each adjacent to the first surface. The concave part of the ith bending part is positioned on at least one of the third surface and the fourth surface. In some embodiments, the recess of the ith bend in the fourth direction extends through the ith bend or does not extend through the ith bend. Wherein the fourth direction is a direction from the third surface to the fourth surface.

In some embodiments, the concentration of the depressions of the ith bend decreases linearly or stepwise in the third direction. That is, the concentration of the concave portions of the portion of the i-th bending portion near the first surface is smaller, so that the supporting ability of the i-th bending portion to the display panel is stronger.

In some embodiments, the flexible support layer further comprises: and the elastic filling material is filled in the hole of at least one of the bending part and the non-bending part. Thus, the supporting capability of the flexible supporting layer on the display panel can be improved.

In a second aspect, there is also provided a flexible display module comprising a flexible support layer according to any one of the first aspects.

In a third aspect, there is also provided a flexible display device comprising a flexible display module as described in the second aspect.

The technical effects obtained by the second and third aspects are similar to the technical effects obtained by the corresponding technical means in the first aspect, and are not described in detail herein.

Drawings

Fig. 1 is a schematic structural view of a first flexible display device provided in the related art;

FIG. 2 is a schematic view of a first flexible support layer provided in the related art;

FIG. 3 is a schematic view of a second flexible support layer provided in the related art;

fig. 4 is a schematic structural view of a second flexible display device provided in the related art;

FIG. 5 is a schematic structural view of a first flexible support layer provided in an embodiment of the present application;

FIG. 6 is a schematic view of a folded structure of a first flexible support layer provided in an embodiment of the present application;

FIG. 7 is a schematic structural view of a second flexible support layer provided in an embodiment of the present application;

FIG. 8 is a schematic view of a folded structure of a second flexible support layer provided in an embodiment of the present application;

FIG. 9 is a schematic view of a folded structure of a third flexible support layer provided in an embodiment of the present application;

FIG. 10 is a gray scale plot of a first foam material provided in an embodiment of the present application;

FIG. 11 is a gray scale of a second foam provided in an embodiment of the present application;

FIG. 12 is a schematic structural view of a third flexible support layer provided in an embodiment of the present application;

FIG. 13 is a schematic structural view of a fourth flexible support layer provided in an embodiment of the present application;

FIG. 14 is a schematic structural view of a fifth flexible support layer provided in an embodiment of the present application;

FIG. 15 is a gray scale view of a structure of a flexible support layer provided in an embodiment of the present application;

Fig. 16 is a schematic structural view of a first bending portion according to an embodiment of the present disclosure;

fig. 17 is a schematic structural view of a second bending portion according to an embodiment of the present disclosure;

FIG. 18 is a schematic structural view of a sixth flexible support layer provided in an embodiment of the present application;

fig. 19 is a schematic structural view of a third bending portion according to an embodiment of the present disclosure;

FIG. 20 is a schematic structural view of a seventh flexible support layer provided in an embodiment of the present application;

FIG. 21 is a schematic structural view of an eighth flexible support layer provided in an embodiment of the present application;

FIG. 22 is a schematic structural view of a ninth flexible support layer provided in an embodiment of the present application;

FIG. 23 is a schematic structural view of a tenth flexible support layer provided in an embodiment of the present application;

fig. 24 is a schematic structural view of a fourth bending portion according to an embodiment of the present disclosure;

fig. 25 is a schematic structural view of a fifth bending portion according to an embodiment of the present disclosure;

fig. 26 is a schematic structural view of a sixth bending portion according to an embodiment of the present disclosure;

fig. 27 is a schematic structural view of a seventh bending portion according to an embodiment of the present application;

fig. 28 is a schematic structural view of an eighth bending portion according to an embodiment of the present disclosure;

fig. 29 is a schematic structural diagram of a flexible display module according to an embodiment of the present application.

Wherein, the meanings represented by the reference numerals are respectively as follows:

120. a display panel;

130. a cover plate;

140. OCA optical adhesive;

related technology:

10. a flexible display device;

110. a flexible support layer;

112. a bending part;

1122. patterning the structure;

1124. a non-patterned structure;

114. a non-bending portion;

the application comprises the following steps:

20. a flexible display module;

201. a recessed portion;

202. a first surface;

204. a second surface;

206. a third surface;

208. a fourth surface;

210. a flexible support layer;

212. a bending part;

2121. a first portion;

2122. a second portion;

2123. a third section;

2124. a fourth section;

2125. a first film layer;

2126. a second film layer;

2127. a third film layer;

214. a non-bending part.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

It should be understood that reference herein to "a plurality" means two or more. In the description of the present application, "/" means or, unless otherwise indicated, for example, a/B may represent a or B; "and/or" herein is merely an association relationship describing an association object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, for the purpose of facilitating the clear description of the technical solutions of the present application, the words "first", "second", etc. are used to distinguish between the same item or similar items having substantially the same function and effect. It will be appreciated by those of skill in the art that the words "first," "second," and the like do not limit the amount and order of execution, and that the words "first," "second," and the like do not necessarily differ.

Before explaining the flexible supporting layer provided in the embodiment of the application in detail, an application scenario of the flexible supporting layer is described.

Fig. 1 is a schematic structural view of a flexible display device 10 provided in the related art. As shown in fig. 1, the foldable flexible display device 10 generally includes a flexible support layer 110, a display panel 120, and a cover plate 130. The flexible support layer 110 is typically a sheet of metal, such as titanium. The flexible support layer 110, the display panel 120, and the cover plate 130 are stacked such that the display panel 120 is positioned between the flexible support layer 110 and the cover plate 130. The flexible support layer 110 and the display panel 120 may be bonded by a transparent adhesive (optically clear adhesive, OCA) optical adhesive 140. Wherein the flexible support layer 110 includes a bent portion 112 and a non-bent portion 114. When the flexible display device 10 is folded, the portion corresponding to the bending portion 112 of the flexible supporting layer 110 is bent, and the portion corresponding to the non-bending portion 114 of the flexible supporting layer 110 is not bent.

Fig. 2 is a schematic structural view of one flexible supporting layer 110 provided in the related art, and fig. 3 is a schematic structural view of another flexible supporting layer 110 provided in the related art. As shown in fig. 2 and 3, in the related art, in order to facilitate folding of the flexible display device 10, a bending portion 112 for bending in the flexible supporting layer 110 is generally provided with a patterned structure 1122. The patterned structure 1122 is generally a hollow structure such as a via hole or a blind hole. The patterned structure 1122 is used to reduce the elastic modulus of the bending portion 112, so that the bending portion 112 of the flexible supporting layer 110 is easier to bend. Fig. 4 is a schematic structural view of another flexible display device 10 provided in the related art. Fig. 1 is a schematic structural diagram of a portion of the flexible display device 10 having no patterned structure 1122 at the bending portion 112 of the flexible supporting layer 110, and fig. 4 is a schematic structural diagram of a portion of the flexible display device 10 having the patterned structure 1122 at the bending portion 112 of the flexible supporting layer 110.

However, in the first aspect, the flexible supporting layer 110 formed of the metal plate material has a large weight, which is disadvantageous for portability of the flexible display device 10. In the second aspect, since the patterned structure 1122 and the non-patterned structure 1124 of the bending portion 112 have distinct boundary lines, which is not beneficial to the transmission of stress, the stress generated by the bending portion 112 provided with the patterned structure 1122 during bending may be concentrated at the non-patterned structure 1124 of the bending portion 112, which may affect the service life of the flexible display device 10. In the third aspect, there is a distinct boundary line between the bent portion 112 provided with the patterned structure 1122 and the non-bent portion 114 not provided with the patterned structure 1122. In this way, after the flexible display device 10 is bent for a plurality of times, an imprint may be generated between the bent portion 112 and the non-bent portion 114. In the fourth aspect, when the flexible display device 10 is bent, the OCA optical adhesive 140 overflows into the patterned structure 1122 after being stressed. In this way, after the flexible display device 10 is bent for a plurality of times, the OCA optical adhesive 140 may accumulate inside the patterned structure 1122, thereby forming an imprint.

Therefore, the embodiment of the application provides the flexible supporting layer, the flexible display module and the flexible display device, which can lighten the weight of the flexible supporting layer, thereby being beneficial to the portability of the flexible display device.

The flexible supporting layer is applied to the flexible display device and used for supporting the display panel. The flexible support layer provided in the embodiments of the present application is explained in detail below. In the drawings provided by the embodiments of the present application, the arrowed curves all point to the surface of the device or structure, and the unbended curves all point to the device or structure itself.

Fig. 5 is a schematic structural diagram of a flexible supporting layer 210 according to an embodiment of the present application. As shown in fig. 5, the flexible support layer 210 may include n+1 non-bent portions 214 and N bent portions 212. The ith bending portion 212 of the N bending portions 212 is connected between the ith non-bending portion 214 and the ith+1th non-bending portion 214 of the n+1th non-bending portions 214. Wherein N is a positive integer, and i is a positive integer less than or equal to N. The "ith bending portion 212 of the N bending portions 212" refers to the ith bending portion 212 counted in the arrangement direction of the N bending portions 212 among the N bending portions 212; the "i-th non-bent portion 214 among the n+1 non-bent portions 214" refers to the i-th non-bent portion 214 counted in the arrangement direction of the n+1 non-bent portions 214 among the n+1 non-bent portions 214. That is, each of the bending portions 212 is connected between two non-bending portions 214, and only one bending portion 212 is connected between two non-bending portions 214. In the embodiment shown in fig. 5, N is equal to 1. That is, the flexible supporting layer 210 includes two non-bent portions 214 and one bent portion 212, and one bent portion 212 is connected between the two non-bent portions 214. Fig. 6 is a schematic diagram of a folding structure of the flexible supporting layer 210 according to an embodiment of the present application, and the folding structure shown in fig. 6 corresponds to the flexible supporting layer 210 shown in fig. 5. As shown in fig. 6, generally, after the flexible supporting layer 210 is applied to the flexible display device, when the flexible display device is folded, that is, when the flexible supporting layer 210 is folded, the bending portion 212 of the flexible supporting layer 210 is in a bending state; when the flexible display device is fully unfolded, that is, the flexible supporting layer 210 is fully unfolded, the bending portion 212 of the flexible supporting layer 210 is in a flat state.

Fig. 7 is a schematic structural diagram of another flexible support layer 210 provided in an embodiment of the present application. In the embodiment shown in fig. 7, N is equal to 2. That is, the flexible support layer 210 includes three non-bent portions 214 and two bent portions 212. Along the direction from left to right of the paper, the first bending portion 212 is connected between the first non-bending portion 214 and the second non-bending portion 214, and the second bending portion 212 is connected between the second non-bending portion 214 and the third non-bending portion 214. Fig. 8 and 9 are schematic diagrams of folding structures of two different flexible support layers 210 according to the embodiments of the present application, and the folding structures shown in fig. 8 and 9 each correspond to the flexible support layer 210 shown in fig. 7. As shown in fig. 8 and 9, when the flexible supporting layer 210 is folded, the bending portion 212 of the flexible supporting layer 210 is in a bent state; when the flexible supporting layer 210 is fully unfolded, the bending portion 212 of the flexible supporting layer 210 is in a flat state.

The material of the flexible support layer 210 is a foam material, and fig. 10 and 11 are gray scale views of two foam materials provided in the embodiments of the present application. The foam material is also called a porous material, and is a material with a certain number of pores and a network structure. Foam differs from a board formed with patterned structures in that: first, the voids in the foam are formed directly during the preparation of the foam, and are naturally formed rather than being processed later, and the patterned structures (including holes) on the plate with the patterned structures are formed by processing the plate after the preparation of the plate. Second, the pores of the foam material are small in pore size, and generally, the foam material is classified according to the pore size of the pores of the foam material, and the foam material includes a microporous material having a pore size of less than 2nm (nanometers), a mesoporous material having a pore size of greater than or equal to 2nm and less than or equal to 50nm, and a macroporous material having a pore size of greater than 50nm, and the size of the patterned structure on the plate formed with the patterned structure is generally in millimeter scale. Third, the voids in the foam are generally polyhedral in shape, the foam is a three-dimensional structure formed by a plurality of polyhedral shaped voids spatially aggregated, and the patterned structure on the sheet with the patterned structure is substantially a planar pattern extending through the sheet.

The foam material can be a metal foam or a polymeric foam. The metal foam may be, for example, titanium foam, silver foam, nickel foam, copper foam, or the like. The polymer foam material may be, for example, polystyrene foam or polyurethane foam. The foam may be made by adding a blowing agent to the molten material such that the blowing agent volatilizes during solidification of the molten material to form voids. For example, titanium foam may be formed by adding a foaming agent to molten titanium and then solidifying the titanium foam; the polystyrene foam may be formed by adding a foaming agent to a polystyrene resin in a molten state and then solidifying the same. The foam may also be directly printed by 3D printing techniques.

The foam has a porosity, which refers to the ratio of the volume of all pores in the foam to the total volume of the foam. The elastic modulus of the foam decreases with increasing porosity. That is, the greater the porosity of the foam, the more easily the foam will deform. In the flexible support layer 210 provided in the embodiments of the present application, the porosity of the bent portion 212 is greater than the porosity of the non-bent portion 214. That is, in the flexible support layer 210 provided herein, the ratio of the volume of all the pores of the bent portion 212 to the total volume of the bent portion 212 is greater than the ratio of the volume of all the pores of the non-bent portion 214 to the total volume of the non-bent portion 214. In the embodiment shown in fig. 5 to 9, the porosity of different portions of the flexible support layer 210 is shown by different pattern filling ratios.

In the present embodiment, the flexible support layer 210 includes a kink 212 and a non-kink 214. The flexible supporting layer 210 is made of foam material, and the porosity of the bending portion 212 is greater than that of the non-bending portion 214, so that the elastic modulus of the bending portion 212 is smaller, and the bending portion 212 is easy to bend. The use of a foam material as the flexible support layer 210 may reduce the weight of the flexible support layer 210, thereby facilitating portability of a flexible display device to which the flexible support layer 210 is applied. Because of the small pore size of the pores of the foam, the pore portion of the bend 212 has no clear boundary with the non-pore portion, which facilitates stress dispersion. In addition, since the pores of the foam material have small pore diameters, when the flexible support layer 210 is applied to a flexible display device, the OCA optical cement attached to the flexible support layer 210 is difficult to be forced to overflow into the pores, so that it is possible to largely prevent the OCA optical cement from accumulating in the pores to generate an imprint.

In some embodiments, the flexible support layer 210 may also include an elastic filler material. The elastic filler material may be, for example, one or more of a thermoplastic elastomer (i.e., synthetic rubber), vulcanized rubber, and silicone rubber. The elastic filling material has higher elasticity. The elastic filler material may be filled in the pores of at least one of the bent portion 212 and the non-bent portion 214. In this way, the support capability of the flexible support layer 210 to the display panel can be improved.

In some embodiments, the ith bend 212 has a central axis, and the ith bend 212 is symmetrical about the central axis of the ith bend 212. The porosity arrangement of the flexible support layer 210 provided in the embodiments of the present application is explained in detail below from two different embodiments. It should be noted that the following two different embodiments may be combined with each other.

In a first possible embodiment, the porosity of the ith bend 212 decreases linearly or stepwise in the first direction X1, or/and in the second direction X2. The first direction X1 refers to a direction from the central axis of the ith bending portion 212 to the ith non-bending portion 214. The second direction X2 refers to a direction from the central axis of the i-th bending portion 212 to the i+1th non-bending portion 214.

As an example, fig. 12 is a schematic structural view of yet another flexible support layer 210 provided in an embodiment of the present application. In the embodiment shown in fig. 12, the flexible supporting layer 210 includes only one bending portion 212 and two non-bending portions 214, and the porosity of different portions of the flexible supporting layer 210 is shown by different pattern filling ratios. As shown in fig. 12, the bending portion 212 of the flexible support layer 210 is divided into a first portion 2121, a second portion 2122, a third portion 2123 and a fourth portion 2124 having equal dimensions, where the first portion 2121, the second portion 2122, the third portion 2123 and the fourth portion 2124 may be an integrally formed structure. The first portion 2121 is located between the first non-bent portion 214 and the second portion 2122, the second portion 2122 is located between the first portion 2121 and the third portion 2123, the third portion 2123 is located between the second portion 2122 and the fourth portion 2124, and the fourth portion 2124 is located between the third portion 2123 and the second non-bent portion 214. In this case, the central axis of the bending portion 212 is the boundary line between the second portion 2122 and the third portion 2123. The porosity of the fourth portion 2124, the third portion 2123, the second portion 2122 and the first portion 2121 decreases stepwise, and the porosity of the first portion 2121 is larger than the porosity of the two non-bent portions 214. For example, the fourth portion 2124 may have a porosity of 95%, the third portion 2123 may have a porosity of 90%, the second portion 2122 may have a porosity of 85%, the first portion 2121 may have a porosity of 80%, and the two non-kinks 214 may have a porosity of 75%. It will be appreciated that the embodiment shown in fig. 12 is such that the porosity of the ith bend 212 decreases stepwise in the first direction X1. In other examples, the porosity of the ith bend 212 may also decrease linearly along the first direction X1. Linear reduction here includes a linear reduction with a slope, as well as a curvilinear reduction.

As another example, as shown in fig. 13, the bending portion 212 of the flexible support layer 210 is still divided into a first portion 2121, a second portion 2122, a third portion 2123, and a fourth portion 2124 that are equal in size, and the first portion 2121, the second portion 2122, the third portion 2123, and the fourth portion 2124 are integrally formed structures. In this case, the central axis of the bending portion 212 is the boundary line between the second portion 2122 and the third portion 2123. That is, the second direction X2 and the first direction X1 are opposite directions. The porosity of the first portion 2121, the second portion 2122, the third portion 2123, and the fourth portion 2124 decreases stepwise, and the porosity of the fourth portion 2124 is greater than the porosity of the two non-bent portions 214. For example, the first portion 2121 may have a porosity of 95%, the second portion 2122 may have a porosity of 90%, the third portion 2123 may have a porosity of 85%, the fourth portion 2124 may have a porosity of 80%, and the two non-bends 214 may have a porosity of 75%. It will be appreciated that the embodiment shown in fig. 13 is such that the porosity of the ith bend 212 decreases stepwise in the second direction X2. In other examples, the porosity of the ith bend 212 may also decrease linearly along the second direction X2. Linear reduction here includes a linear reduction with a slope, as well as a curvilinear reduction.

As yet another example, as shown in fig. 14, the bending portion 212 of the flexible support layer 210 is still divided into a first portion 2121, a second portion 2122, a third portion 2123, and a fourth portion 2124 that are equal in size, and the first portion 2121, the second portion 2122, the third portion 2123, and the fourth portion 2124 are integrally formed structures. In this case, the central axis of the bending portion 212 is the boundary line between the second portion 2122 and the third portion 2123. The porosity of the first portion 2121 may be less than the porosity of the second portion 2122 and the porosity of the fourth portion 2124 may be less than the porosity of the third portion 2123. For example, the first portion 2121 may have a porosity of 80%, the second portion 2122 may have a porosity of 90%, the third portion 2123 may have a porosity of 90%, the fourth portion 2124 may have a porosity of 80%, and the two non-kinks 214 may have a porosity of 70%. It will be appreciated that the embodiment shown in fig. 14 is such that the porosity of the portion of the i-th bending portion 212 between the i-th non-bending portion 214 and the central axis of the i-th bending portion 212 decreases stepwise in the first direction X1, and the porosity of the portion of the i-th bending portion 212 between the central axis of the i-th bending portion 212 and the i+1-th non-bending portion 214 decreases stepwise in the second direction X2. In other examples, the porosity of the portion of the i-th bend 212 between the i-th non-bend 214 and the central axis of the i-th bend 212 may also decrease linearly along the first direction X1, and the porosity of the portion of the i-th bend 212 between the central axis of the i-th bend 212 and the i+1th non-bend 214 may decrease linearly along the second direction X2. Linear reduction here includes a linear reduction with a slope, as well as a curvilinear reduction.

Fig. 15 is a gray scale view of a structure of the flexible supporting layer 210 according to an embodiment of the present application, and the structure shown in fig. 15 corresponds to the flexible supporting layer 210 shown in fig. 14. As shown in fig. 15, the bent portion 212 of the flexible support layer 210 is divided into a first portion 2121, a second portion 2122, and a third portion 2123. Wherein the first portion 2121 and the third portion 2123 have equal widths in the first direction X1. The width of the first non-bending portion 214 along the first direction X1 is equal to the width of the second bending portion 212 along the first direction X1. In this case, the central axis of the i-th bending portion 212 is the central axis of the second portion 2122. The second portion 2122 is symmetrical about the central axis of the ith fold 212, and the first portion 2121 and the third portion 2123 are also symmetrical about the central axis of the ith fold 212. The two non-bends 214 are also symmetrical about the central axis of the ith bend 212. In this simulated structure, the porosity of the two non-bends 214 is 50%, the porosity of the first portion 2121 and the third portion 2123 is 80%, and the porosity of the second portion 2122 is 90%. In this way, the first portion 2121 and the third portion 2123 of the bending portion 212 form a transition region, and when the bending portion 212 of the flexible supporting layer 210 bends, the elastic modulus of the bending portion 212 gradually increases along the first direction X1 and the second direction X2, so that the safety of the flexible supporting layer 210 in the bending process can be improved. Meanwhile, since the first portion 2121 and the third portion 2123 of the bending portion 212 form a transition region, there is no distinct boundary between the bending portion 212 and the non-bending portion 214, so that an imprint between the bending portion 212 and the non-bending portion 214 after the flexible supporting layer 210 is bent for many times can be avoided.

It will be appreciated that in the above description of fig. 14 and 15, the porosity of the flexible support layer 210 is uniform at a location symmetrical about the central axis of the i-th bending portion 212. That is, in fig. 14, the porosities of the two bent portions 212 are the same, the porosities of the first portion 2121 and the fourth portion 2124 are the same, and the porosities of the second portion 2122 and the third portion 2123 are the same. In this way, the flexible supporting layer 210 can provide a symmetrically balanced supporting force for the display panel, and the supporting capability of the flexible supporting layer 210 is improved. In other embodiments, the porosity of the flexible support layer 210 may be different at locations symmetrical about the central axis of the ith bend 212, e.g., the porosity of the first non-bend 214 may be 60% and the porosity of the second non-bend 214 may be 70% for the flexible support layer 210 shown in fig. 14. The porosity of the first portion 2121 may be 75%, the porosity of the second portion 2122 may be 85%, the porosity of the third portion 2123 may be 90%, and the porosity of the fourth portion 2124 may be 80%.

It will be appreciated that in the embodiments shown in fig. 12-15 described above, the flexible support layer 210 includes only one bend 212. In other embodiments, not shown, the flexible support layer 210 may also include two or three bends 212. When the flexible support layer 210 includes more than one bend 212, the porosity at the same location of different bends 212 may be the same or different, and wherein the change in porosity of each bend 212 may be as shown in any of fig. 12-15.

In a second possible embodiment, the ith bend 212 has opposing first and

second surfaces

202, 204. The first surface 202 is for supporting a display panel. In the third direction Z, the porosity of the ith bend 212 decreases linearly or in steps. Wherein the third direction Z is a direction from the second surface 204 to the first surface 202.

As an example, fig. 16 is a schematic structural view of a bending portion 212 according to an embodiment of the present application. In the embodiment shown in fig. 16, the porosity of different portions of the bending portion 212 is shown by different pattern filling ratios. As shown in fig. 16, the bend 212 has a first surface 202 and a second surface 204. When the flexible supporting layer 210 is applied to the flexible display device, a portion of the display panel corresponding to the bending portion 212 is located on the first surface 202 of the bending portion 212. The third direction Z is a direction from the second surface 204 to the first surface 202, that is, the third direction Z is a thickness direction of the bending portion 212, the third direction Z is perpendicular to the first direction X1, and the third direction Z is perpendicular to the second direction X2. Along the third direction Z, the bending portion 212 of the flexible supporting layer 210 is divided into a second film layer 2126 and a first film layer 2125, where the second film layer 2126 and the first film layer 2125 may be an integrally formed structure. The surface of the first film 2125 away from the second film 2126 is a first surface 202, and the surface of the second film 2126 away from the first film 2125 is a second surface 204. The porosity of the first film 2125 may be less than the porosity of the second film 2126 such that the porosity of the fold 212 decreases stepwise along the third direction Z. For example, the porosity of the second film layer 2126 may be 90% and the porosity of the first film layer 2125 may be 70%.

As another example, as shown in fig. 17, the bending portion 212 of the flexible supporting layer 210 may be divided into a second film layer 2126, a third film layer 2127 and a first film layer 2125 along the third direction Z, and the second film layer 2126, the third film layer 2127 and the first film layer 2125 are integrally formed. The third film 2127 is located between the second film 2126 and the first film 2125. The surface of the first film 2125 away from the second film 2126 is a first surface 202, and the surface of the second film 2126 away from the first film 2125 is a second surface 204. The first film 2125 has a porosity that is less than the porosity of the third film 2127, and the third film 2127 has a porosity that is less than the porosity of the second film 2126, so that the porosity of the fold 212 decreases stepwise along the third direction Z. For example, the porosity of the second film 2126 may be 90%, the porosity of the third film 2127 may be 70%, and the porosity of the first film 2125 may be 50%. It will be appreciated that in the embodiment shown in fig. 16 and 17, the porosity of the bend 212 decreases stepwise in the third direction Z. In other embodiments, not shown, the porosity of the bend 212 may also decrease linearly along the third direction Z. Linear reduction here includes a linear reduction with a slope, as well as a curvilinear reduction. In this manner, the portion of the ith bend 212 proximate to the first surface 202 is less porous, thereby providing the ith bend 212 with greater support for the display panel.

In some embodiments, the ith bend 212 also has a recess 201. The recess 201 is a patterned structure formed at the bending portion 212. In this way, the modulus of elasticity of the i-th bending portion 212 can be reduced, thereby making the bending portion 212 more easily bendable.

The following describes the position and arrangement of the concave portions 201 of the flexible supporting layer 210 according to the embodiment of the present application in detail from two different embodiments. It should be noted that the following two different embodiments may be combined with each other.

In a first possible embodiment, the recess 201 of the ith bending portion 212 is located on the second surface 204. In the third direction Z, the recess 201 of the ith bending portion 212 penetrates the ith bending portion 212, or the recess 201 of the ith bending portion 212 does not penetrate the ith bending portion 212.

As an example, fig. 18 is a schematic structural view of yet another flexible support layer 210 provided in an embodiment of the present application. In the embodiment shown in fig. 18, the flexible supporting layer 210 includes only one bending portion 212 and two non-bending portions 214, and the porosity of different portions of the flexible supporting layer 210 is shown by different pattern filling ratios. For ease of understanding, in the embodiment shown in fig. 18, a fourth direction Y is also defined, which is perpendicular to all of the first direction X1, the second direction X2, and the third direction Z. That is, the surfaces formed by the fourth direction Y and the first direction X1 and the second direction X2 are parallel to the first surface 202 and the second surface 204.

As shown in fig. 18, the bending portion 212 has a concave portion 201. The recess 201 may be located on the second surface 204 of the bending portion 212 or may be located on the first surface 202 of the bending portion 212. In the third direction Z, the recess 201 extends toward the inside of the bending portion 212, and the recess 201 may or may not penetrate the bending portion 212. Fig. 19 is a schematic structural view of another bending portion 212 according to an embodiment of the present application. In some embodiments, as shown in fig. 19, the recess 201 is located on the second surface 204 of the bending portion 212, and along the third direction Z, the recess 201 does not penetrate through the bending portion 212. In this way, the OCA optical adhesive can be prevented from overflowing into the recess 201 after being stressed when the flexible display device applied by the flexible supporting layer 210 is bent, so as to prevent the OCA optical adhesive from accumulating in the recess 201 to generate an imprint. In other examples, as shown in fig. 20, the recess 201 located on the second surface 204 of the bending portion 212 may also penetrate the bending portion 212 along the third direction Z. In this case, the recess 201 may be considered to be located on the first surface 202 of the bent portion 212 and penetrate the bent portion 212 in the third direction Z.

Further, the concentration of the concave portions 201 of the i-th bending portion 212 decreases linearly or stepwise in the first direction X1, or/and in the second direction X2.

As an example, fig. 21 is a schematic structural view of yet another flexible support layer 210 provided in an embodiment of the present application. Wherein in the embodiment shown in fig. 21, the flexible support layer 210 includes only one kink 212 and two non-kinks 214. As shown in fig. 21, the bending portion 212 of the flexible support layer 210 is divided into a first portion 2121, a second portion 2122, a third portion 2123 and a fourth portion 2124 having equal dimensions, where the first portion 2121, the second portion 2122, the third portion 2123 and the fourth portion 2124 may be an integrally formed structure. The first portion 2121 is located between the first non-bent portion 214 and the second portion 2122, the second portion 2122 is located between the first portion 2121 and the third portion 2123, the third portion 2123 is located between the second portion 2122 and the fourth portion 2124, and the fourth portion 2124 is located between the third portion 2123 and the second non-bent portion 214. The concentration of the depressions 201 of the fourth portion 2124, the third portion 2123, the second portion 2122 and the first portion 2121 decreases stepwise. Taking the fourth portion 2124 as an example, assuming that each of the concave portions 201 is circular in shape with a radius r on the second surface 204, the width of the second surface 204 in the first direction X1 of the fourth portion 2124 is m, and the length of the second surface 204 in the fourth direction Y of the fourth portion 2124 is n, the concentration of the concave portions 201 in the fourth portion 2124 is 14×pi r ² /mn. It will be appreciated that the embodiment shown in fig. 21 is such that the concentration of the concave portions 201 of the i-th bending portion 212 decreases stepwise in the first direction X1. In other examples, the concentration of the concave portions 201 of the i-th bending portion 212 may also decrease linearly along the first direction X1.

As another example, as shown in fig. 22, the bending portion 212 of the flexible support layer 210 is still divided into a first portion 2121, a second portion 2122, a third portion 2123, and a fourth portion 2124 that are equal in size, and the first portion 2121, the second portion 2122, the third portion 2123, and the fourth portion 2124 are integrally formed structures. The concentration of the depressions 201 of the first, second, third and

fourth portions

2121, 2122, 2123, 2124 decreases stepwise. In other embodiments, the concentration of the concave portions 201 of the ith bending portion 212 may also decrease linearly along the second direction X2.

As yet another example, as shown in fig. 23, the bending portion 212 of the flexible support layer 210 is still divided into a first portion 2121, a second portion 2122, a third portion 2123, and a fourth portion 2124 that are equal in size, and the first portion 2121, the second portion 2122, the third portion 2123, and the fourth portion 2124 are integrally formed structures. The concentration of the depressions 201 of the first portion 2121 is less than the concentration of the depressions 201 of the second portion 2122 and the concentration of the depressions 201 of the fourth portion 2124 is less than the concentration of the depressions 201 of the third portion 2123. It will be appreciated that the embodiment shown in fig. 23 is such that the concentration of the concave portions 201 of the portion of the i-th bending portion 212 located between the i-th non-bending portion 214 and the central axis of the i-th bending portion 212 decreases stepwise in the first direction X1, and the concentration of the concave portions 201 of the portion of the i-th bending portion 212 located between the central axis of the i-th bending portion 212 and the i+1-th non-bending portion 214 decreases stepwise in the second direction X2. In other examples, the concentration of the concave portion 201 of the portion of the i-th bending portion 212 between the i-th non-bending portion 214 and the central axis of the i-th bending portion 212 may also decrease linearly along the first direction X1, and the concentration of the concave portion 201 of the portion of the i-th bending portion 212 between the central axis of the i-th bending portion 212 and the i+1-th non-bending portion 214 may also decrease linearly along the second direction X2. In this example, a transition region may be formed at a portion (i.e., the first portion 2121 and the fourth portion 2124) of the ith bending portion 212 near the non-bending portion 214, and when the bending portion 212 of the flexible supporting layer 210 is bent, an elastic modulus of the bending portion 212 may be gradually increased along the first direction X1 and the second direction X2, so that safety of the flexible supporting layer 210 during bending may be improved. Meanwhile, since the i-th bending portion 212 forms a transition region near the non-bending portion 214, there is no distinct boundary between the bending portion 212 and the non-bending portion 214, so that an imprint between the bending portion 212 and the non-bending portion 214 after the flexible supporting layer 210 is bent for many times can be avoided.

It will be appreciated that in the above description of fig. 23, the concentration of the concave portions 201 in the i-th bending portion 212 is the same at the symmetrical position with respect to the central axis of the i-th bending portion 212. That is, the first portion 2121 and the fourth portion 2124 of fig. 23 have the same density of depressions 201, and the second portion 2122 and the third portion 2123 have the same density of depressions 201. In this way, the bending portion 212 can provide a symmetrically balanced supporting force for the display panel, and the supporting capability of the flexible supporting layer 210 is improved. In other examples, the concentration of the depressions 201 in the ith bend 212 may be different at locations symmetrical about the central axis of the ith bend 212.

It will be appreciated that in the embodiment shown in fig. 21-23 described above, the flexible support layer 210 includes only one bend 212. In other embodiments, not shown, the flexible support layer 210 may also include two or three bends 212. When the flexible support layer 210 includes more than one bending portion 212, the densities of the concave portions 201 at the same position of different bending portions 212 may be the same or different, and wherein the change in the densities of the concave portions 201 of each bending portion 212 may be as shown in any one of fig. 21 to 23.

In a second possible embodiment, the ith fold 212 also has opposed third and

fourth surfaces

206, 208, each of the third and

fourth surfaces

206, 208 being adjacent to the first surface 202. That is, the direction from the third surface 206 to the third surface 206 is the fourth direction Y. The recess 201 of the ith bending portion 212 is located on at least one of the third surface 206 and the fourth surface 208. In the fourth direction Y, the recess 201 of the ith bending portion 212 penetrates the ith bending portion 212 or does not penetrate the ith bending portion 212.

As an example, fig. 24 and 25 are schematic structural views of different bending portions 212 provided in the embodiments of the present application. As shown in fig. 24 and 25, the bending portion 212 further has a third surface 206 and a fourth surface 208, the third surface 206 and the fourth surface 208 are opposite, and the third surface 206 and the fourth surface 208 are adjacent to the first surface 202, and the third surface 206 and the fourth surface 208 are also adjacent to the second surface 204. The bending portion 212 has a concave portion 201. In the embodiment shown in fig. 24, the recess 201 is located on the third surface 206 of the bending portion 212; in the embodiment shown in fig. 25, the recess 201 is located on the fourth surface 208 of the bent portion 212. In the fourth direction Y, the recess 201 extends toward the inside of the bending portion 212, and the recess 201 may or may not penetrate the bending portion 212. In the embodiment shown in fig. 24 and 25, the recess 201 does not penetrate the bent portion 212. In the embodiment shown in fig. 26, the recess 201 is located on the third surface 206 of the bending portion 212, and the recess 201 penetrates the bending portion 212 along the fourth direction Y. In this case, the recess 201 may be considered to be located on the fourth surface 208 of the bent portion 212 and penetrate the bent portion 212 in the fourth direction Y.

Further, in the third direction Z, the concentration of the concave portions 201 of the i-th bending portion 212 is linearly reduced or stepwise reduced.

As an example, as shown in fig. 27, the bending portion 212 of the flexible supporting layer 210 is divided into a second film layer 2126 and a first film layer 2125 along the third direction Z, where the second film layer 2126 and the first film layer 2125 may be an integrally formed structure. The surface of the first film 2125 away from the second film 2126 is a first surface 202, and the surface of the second film 2126 away from the first film 2125 is a second surface 204. The concentration of the depressions 201 of the first film 2125 may be less than the concentration of the depressions 201 of the second film 2126 such that the concentration of the depressions 201 of the kink 212 decreases stepwise along the third direction Z.

As another example, as shown in fig. 28, the bending portion 212 of the flexible supporting layer 210 may be divided into a second film layer 2126, a third film layer 2127 and a first film layer 2125 along the third direction Z, and the second film layer 2126, the third film layer 2127 and the first film layer 2125 are integrally formed. The third film 2127 is located between the second film 2126 and the first film 2125. The surface of the first film 2125 away from the second film 2126 is a first surface 202, and the surface of the second film 2126 away from the first film 2125 is a second surface 204. The concentration of the concave portions 201 of the first film 2125 is less than the concentration of the concave portions 201 of the third film 2127, and the concentration of the concave portions 201 of the third film 2127 is less than the concentration of the concave portions 201 of the second film 2126, so that the concentration of the concave portions 201 of the bending portion 212 is reduced stepwise in the third direction Z. In other embodiments, not shown, the concentration of the recesses 201 of the bent portion 212 may also decrease linearly along the third direction Z. In this way, the concentration of the concave portions 201 of the portion of the i-th bending portion 212 near the first surface 202 is smaller, so that the supporting capability of the i-th bending portion 212 to the display panel is stronger.

The flexible supporting layer 210 provided in the embodiment of the application has the following beneficial effects:

The ith bending portion 212 has the recess 201, and the elastic modulus of the ith bending portion 212 can be reduced, so that the bending portion 212 is more easily bent. The recess 201 of the ith bending portion 212 is located on the second surface 204, and the recess 201 of the ith bending portion 212 does not penetrate through the ith bending portion 212 along the third direction Z, so that the OCA optical cement attached to the flexible supporting layer 210 can be prevented from being forced to overflow into the recess 201, and thus, the imprint generated by accumulation of the OCA optical cement in the recess 201 can be prevented. The porosity or the concentration of the concave portion 201 of the portion of the i-th bending portion 212 located between the i-th non-bending portion 214 and the central axis of the i-th bending portion 212 decreases linearly or stepwise in the first direction X1, and the porosity or the concentration of the concave portion 201 of the portion of the i-th bending portion 212 located between the central axis of the i-th bending portion 212 and the i+1-th non-bending portion 214 decreases linearly or stepwise in the second direction X2. In this way, the portion where the porosity of the bending portion 212 or the concentration of the concave portion 201 is linearly reduced or the gradient is reduced forms a transition region, on one hand, when the bending portion 212 of the flexible supporting layer 210 is bent, the elastic modulus of the bending portion 212 gradually increases along the first direction X1 and the second direction X2, so that the safety of the flexible supporting layer 210 in the bending process can be improved. On the other hand, there is no distinct boundary between the bending portion 212 and the non-bending portion 214, so that an imprint between the bending portion 212 and the non-bending portion 214 after the flexible supporting layer 210 is bent many times can be avoided. The porosity or the concentration of the concave portions 201 in the flexible support layer 210 are the same at the portion symmetrical about the central axis of the i-th bending portion 212. In this way, the flexible supporting layer 210 can provide a symmetrically balanced supporting force for the display panel, and the supporting capability of the flexible supporting layer 210 is improved. The portion of the ith bend 212 adjacent to the first surface 202 has less porosity or the concentration of the depressions 201, thereby making the ith bend 212 more supportive of the display panel.

Embodiments of the present application also provide a flexible display module 20, including the flexible supporting layer 210 described in any of the embodiments above.

Specifically, fig. 29 is a schematic structural diagram of a flexible display module 20 according to an embodiment of the present application. As shown in fig. 29, the flexible display module 20 includes a flexible support layer 210, a display panel 120, and a cover plate 130. The flexible support layer 210, the display panel 120, and the cover plate 130 are stacked such that the display panel 120 is located between the flexible support layer 210 and the cover plate 130. The flexible support layer 210 and the display panel 120 may be bonded by the OCA optical adhesive 140.

In some embodiments, flexible support layer 210 includes n+1 non-bends 214 and N bends 212. The ith bending portion 212 of the N bending portions 212 is connected between the ith non-bending portion 214 and the ith+1th non-bending portion 214 of the n+1th non-bending portions 214. Wherein N is a positive integer, and i is a positive integer less than or equal to N. That is, each of the bending portions 212 is connected between two non-bending portions 214, and only one bending portion 212 is connected between two non-bending portions 214. Thus, after the flexible supporting layer 210 is applied to the flexible display device, when the flexible display device is folded, the bending portion 212 of the flexible supporting layer 210 is in a bending state; when the flexible display device is fully unfolded, the bending portion 212 of the flexible supporting layer 210 is in a flat state.

The material of the flexible support layer 210 is a foam material. The foam material is also called a porous material, and is a material with a certain number of pores and a network structure. The foam material can be foamed metal or polymer foam material. The metal foam may be, for example, titanium foam, silver foam, nickel foam, copper foam, or the like. In the flexible support layer 210 provided herein, the porosity of the kink 212 is greater than the porosity of the non-kink 214. Porosity refers to the ratio of the volume of all pores in the foam to the total volume of the foam. That is, in the flexible support layer 210 provided herein, the ratio of the volume of all the pores of the bent portion 212 to the total volume of the bent portion 212 is greater than the ratio of the volume of all the pores of the non-bent portion 214 to the total volume of the non-bent portion 214. In this way, the elastic modulus of the bending portion 212 is smaller than that of the non-bending portion 214, so that the bending portion 212 of the flexible supporting layer 210 is easier to bend.

In the present embodiment, the flexible support layer 210 includes a kink 212 and a non-kink 214. The flexible supporting layer 210 is made of foam material, and the porosity of the bending portion 212 is greater than that of the non-bending portion 214, so that the elastic modulus of the bending portion 212 is smaller than that of the non-bending portion 214, and the bending portion 212 is easy to bend. The use of a foam material as the flexible support layer 210 may reduce the weight of the flexible support layer 210, thereby facilitating portability of a flexible display device to which the flexible support layer 210 is applied. Because of the small pore size of the pores of the foam, the pore portion of the bend 212 has no clear boundary with the non-pore portion, which facilitates stress dispersion. In addition, since the pores of the foam material have small pore diameters, when the flexible support layer 210 is applied to a flexible display device, the OCA optical cement 140 attached to the flexible support layer 210 is difficult to be forced to overflow into the pores, so that the imprint generated by accumulation of the OCA optical cement 140 in the pores can be largely prevented.

In some embodiments, the ith bend 212 has a central axis. The ith bending portion 212 is symmetrical about the central axis of the ith bending portion 212.

In some embodiments, the porosity of the ith bend 212 decreases linearly or stepwise in the first direction X1, or/and in the second direction X2. The first direction X1 refers to a direction from the central axis of the ith bending portion 212 to the ith non-bending portion 214. The second direction X2 refers to a direction from the central axis of the i-th bending portion 212 to the i+1th non-bending portion 214. In some particular embodiments, the porosity of the portion of the ith bend 212 between the ith non-bend 214 and the central axis of the ith bend 212 decreases linearly or in steps in the first direction X1, and the porosity of the portion of the ith bend 212 between the central axis of the ith bend 212 and the (i+1) th non-bend 214 decreases linearly or in steps in the second direction X2. In this way, the portion with the linearly reduced or stepped porosity of the bending portion 212 forms a transition region, and when the bending portion 212 of the flexible supporting layer 210 bends, the elastic modulus of the bending portion 212 gradually increases along the first direction X1 and the second direction X2, so that the safety of the flexible supporting layer 210 in the bending process can be improved.

In some embodiments, the porosity of the flexible support layer 210 is the same at locations symmetrical about the central axis of the ith bend 212. In this way, the flexible supporting layer 210 can provide a symmetrically balanced supporting force for the display panel 120, and the supporting capability of the flexible supporting layer 210 is improved.

In some embodiments, the ith bend 212 has opposing first and

second surfaces

202, 204. The first surface 202 is used to support the display panel 120. In the third direction Z, the porosity of the ith bend 212 decreases linearly or in steps. Wherein the third direction Z is a direction from the second surface 204 to the first surface 202. That is, the portion of the ith bent portion 212 near the first surface 202 has smaller porosity, so that the ith bent portion 212 has a stronger supporting capability for the display panel 120.

In some embodiments, the ith bend 212 has a recess 201. The recess 201 may be a patterned structure formed at the i-th bending portion 212. In this way, the modulus of elasticity of the i-th bending portion 212 can be reduced, thereby making the bending portion 212 more easily bendable.

In some embodiments, the ith bend 212 has opposing first and

second surfaces

202, 204. The first surface 202 is used to support the display panel 120. The recess 201 of the ith bending portion 212 is located on the second surface 204. In some embodiments, in the third direction Z, the recess 201 of the ith bend 212 extends through the ith bend 212 or does not extend through the ith bend 212. In the case that the recess 201 of the ith bending portion 212 is located on the second surface 204 and the recess 201 of the ith bending portion 212 does not penetrate through the ith bending portion 212 along the third direction Z, when the flexible supporting layer 210 is applied to a flexible display device, the OCA optical adhesive 140 attached to the flexible supporting layer 210 can be prevented from being forced to overflow into the recess 201, so that the OCA optical adhesive 140 can be prevented from accumulating in the recess 201.

In some embodiments, the concentration of the depressions 201 of the ith bend 212 decreases linearly or in steps in the first direction X1, or/and in the second direction X2. In some embodiments, the concentration of the concave portion 201 decreases linearly or in steps in the first direction X1 at a portion of the ith bend 212 between the ith non-bend 214 and the central axis of the ith bend 212, and decreases linearly or in steps in the second direction X2 at a portion of the ith bend 212 between the central axis of the ith bend 212 and the (i+1) th non-bend 214. In this way, a transition region can be formed at the portion of the ith bending portion 212 near the non-bending portion 214, and when the bending portion 212 of the flexible supporting layer 210 is bent, the elastic modulus of the bending portion 212 gradually increases along the first direction X1 and the second direction X2, so that the safety of the flexible supporting layer 210 in the bending process can be improved.

In some embodiments, the ith fold 212 also has opposing third and

fourth surfaces

206, 208, each of the third and

fourth surfaces

206, 208 being adjacent to the first surface 202. The recess 201 of the ith bending portion 212 is located on at least one of the third surface 206 and the fourth surface 208. In some embodiments, in the fourth direction Y, the recess 201 of the ith bend 212 extends through the ith bend 212 or does not extend through the ith bend 212. Wherein the fourth direction Y is a direction from the third surface 206 to the fourth surface 208.

In some embodiments, the concentration of the depressions 201 of the ith bend 212 decreases linearly or in steps along the third direction Z. That is, the concentration of the concave portions 201 of the portion of the i-th bending portion 212 near the first surface 202 is smaller, so that the supporting capability of the i-th bending portion 212 to the display panel 120 is stronger.

In some embodiments, the flexible support layer 210 further comprises: and an elastic filler material filled in the aperture of at least one of the bent portion 212 and the non-bent portion 214. In this way, the supporting capability of the flexible supporting layer 210 to the display panel 120 can be improved.

The embodiment of the application further provides a flexible display device, which includes the flexible display module 20 in any one of the embodiments.

The flexible display module 20 and the flexible display device provided in the embodiments of the present application have the following beneficial effects:

in the present embodiment, the flexible support layer 210 includes a kink 212 and a non-kink 214. The flexible supporting layer 210 is made of foam material, and the porosity of the bending portion 212 is greater than that of the non-bending portion 214, so that the elastic modulus of the bending portion 212 is smaller, and the bending portion 212 is easy to bend. The use of a foam material as the flexible support layer 210 may reduce the weight of the flexible support layer 210, thereby facilitating portability of a flexible display device to which the flexible support layer 210 is applied. Because of the small pore size of the pores of the foam, the pore portion of the bend 212 has no clear boundary with the non-pore portion, which facilitates stress dispersion. In addition, since the pores of the foam material have small pore diameters, when the flexible support layer 210 is applied to a flexible display device, the OCA optical cement 140 attached to the flexible support layer 210 is difficult to be forced to overflow into the pores, so that the imprint generated by accumulation of the OCA optical cement 140 in the pores can be largely prevented.

The ith bending portion 212 has the recess 201, and the elastic modulus of the ith bending portion 212 can be reduced, so that the bending portion 212 is more easily bent. The recess 201 of the ith bending portion 212 is located on the second surface 204, and the recess 201 of the ith bending portion 212 does not penetrate through the ith bending portion 212 along the third direction Z, so that the OCA optical cement 140 attached to the flexible supporting layer 210 can be prevented from being forced to overflow into the recess 201, and thus the imprint generated by accumulation of the OCA optical cement 140 in the recess 201 can be prevented. The porosity or the concentration of the concave portion 201 of the portion of the i-th bending portion 212 located between the i-th non-bending portion 214 and the central axis of the i-th bending portion 212 decreases linearly or stepwise in the first direction X1, and the porosity or the concentration of the concave portion 201 of the portion of the i-th bending portion 212 located between the central axis of the i-th bending portion 212 and the i+1-th non-bending portion 214 decreases linearly or stepwise in the second direction X2. In this way, the portion where the porosity of the bending portion 212 or the concentration of the concave portion 201 is linearly reduced or the gradient is reduced forms a transition region, on one hand, when the bending portion 212 of the flexible supporting layer 210 is bent, the elastic modulus of the bending portion 212 gradually increases along the first direction X1 and the second direction X2, so that the safety of the flexible supporting layer 210 in the bending process can be improved. On the other hand, there is no distinct boundary between the bending portion 212 and the non-bending portion 214, so that an imprint between the bending portion 212 and the non-bending portion 214 after the flexible supporting layer 210 is bent many times can be avoided. The porosity or the concentration of the concave portions 201 in the flexible support layer 210 are the same at the portion symmetrical about the central axis of the i-th bending portion 212. In this way, the flexible supporting layer 210 can provide a symmetrically balanced supporting force for the display panel 120, and the supporting capability of the flexible supporting layer 210 is improved. The portion of the ith bent portion 212 near the first surface 202 has less porosity or the concentration of the concave portion 201, so that the ith bent portion 212 has a stronger supporting capability on the display panel 120.

The above embodiments are only for illustrating the technical solution of the present application, and are not limiting; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application, and are intended to be included in the scope of the present application.

Claims

1. A flexible support layer, characterized in that the material of the flexible support layer is a foam material, the foam material is a material with pores and in a network structure, and the pores are non-patterned structures formed directly in the preparation process of the foam material; the flexible supporting layer comprises n+1 non-bending parts and N bending parts, wherein the ith bending part in the N bending parts is connected between the ith non-bending part in the n+1 non-bending parts and the ith+1 non-bending parts, N is a positive integer, i is a positive integer smaller than or equal to N, the porosity of the bending parts is larger than that of the non-bending parts, the porosity of the bending parts is the ratio of the volume of all pores in the bending parts to the total volume of the bending parts, and the porosity of the non-bending parts is the ratio of the volume of all pores in the non-bending parts to the total volume of the non-bending parts.

2. The flexible support layer of claim 1 wherein the ith bend has a central axis and the ith bend is symmetrical about the central axis of the ith bend.

3. The flexible support layer of claim 2, wherein the porosity of the ith bend decreases linearly or stepwise in a direction from the central axis of the ith bend to the ith non-bend and/or in a direction from the central axis of the ith bend to the (i+1) th non-bend.

4. A flexible support layer according to claim 2 or claim 3, wherein the porosity of the flexible support layer is the same at a location symmetrical about the central axis of the ith bend.

5. The flexible support layer of any of claims 1 to 4, wherein the i-th bend has opposing first and second surfaces, the first surface for supporting a display panel;

the porosity of the ith bend decreases linearly or stepwise in a direction from the second surface to the first surface.

6. The flexible support layer of any of claims 1 to 5, wherein the ith bend has a depression.

7. The flexible support layer of claim 6, wherein the ith bend has opposing first and second surfaces, the first surface for supporting a display panel;

the concave part of the ith bending part is positioned on the second surface.

8. The flexible support layer of claim 7, wherein the recess of the ith bend extends through the ith bend in a direction from the second surface to the first surface; or, the concave part of the ith bending part does not penetrate through the ith bending part.

9. The flexible support layer of claim 7 or 8, wherein the ith bend has a central axis, the ith bend is symmetrical about the central axis of the ith bend, and the ith non-bend and the (i+1) th non-bend are symmetrical about the central axis of the ith bend;

the concentration of the concave parts of the ith bending part is linearly reduced or reduced in a gradient manner along the direction from the central axis of the ith bending part to the ith non-bending part and/or along the direction from the central axis of the ith bending part to the (i+1) th non-bending part.

10. The flexible support layer of claim 6, wherein the ith bend has a first surface for supporting a display panel; the ith bending part is also provided with a third surface and a fourth surface which are opposite, and the third surface and the fourth surface are adjacent to the first surface;

the concave part of the ith bending part is positioned on at least one of the third surface and the fourth surface.

11. The flexible support layer of claim 10, wherein the recess of the ith bend extends through the ith bend in a direction from the third surface to the fourth surface; or, the concave part of the ith bending part does not penetrate through the ith bending part.

12. The flexible support layer of claim 10 or 11, wherein the ith bend further has a second surface opposite the first surface, the concentration of the depressions of the ith bend decreasing linearly or in steps in a direction from the second surface to the first surface.

13. The flexible support layer of any of claims 1 to 12, wherein the flexible support layer further comprises: and the elastic filling material is filled in the hole of at least one of the bending part and the non-bending part.

14. A flexible support layer according to any one of claims 1 to 13, wherein the foam material is a metal foam or a polymeric foam material.

15. A flexible display module comprising a flexible support layer according to any one of claims 1 to 14.

16. A flexible display device comprising the flexible display module of claim 15.