1. A foldable display device, comprising:

a flexible display panel;

the supporting component is positioned on one side of the flexible display panel, which is deviated from the light emergent side; the support assembly comprises a support part and a temperature adjusting part; the temperature adjusting part is positioned on one side of the supporting part far away from the flexible display panel;

the supporting part comprises a bending area and a non-bending area, the material of the supporting part positioned in the bending area comprises shape memory alloy, and the supporting part positioned in the bending area comprises a hollow part;

the orthographic projection of the temperature adjusting part on the plane of the supporting part is located in the non-bending area, and the temperature adjusting part is used for adjusting the temperature of the shape memory alloy.

2. The foldable display device of claim 1,

the shape memory alloy includes a two-way shape memory alloy or a one-way shape memory alloy.

3. The foldable display device of claim 1,

the temperature adjusting part comprises an induction controller and a heat source; the induction controller is electrically connected with the heat source;

the induction controller and the heat source are both positioned on one side of the supporting part far away from the flexible display panel;

the sensing controller is used for sensing an external load applied to the foldable display device and controlling the opening and closing of the heat source according to the external load.

4. The foldable display device of claim 3, further comprising:

a driving chip and a power supply; at least one of the power supply and the driving chip is electrically connected with the induction controller; and/or at least one of the power supply and the driving chip is multiplexed as the heat source.

5. The foldable display device of claim 4,

the temperature adjusting part also comprises a heat storage part, and the heat storage part is positioned on one side of the supporting part far away from the flexible display panel;

the heat storage part is used for storing heat emitted by the driving chip and the power supply in the process of driving the flexible display panel to display and releasing heat to the supporting part according to the external load.

6. The foldable display device of claim 5,

the foldable display device comprises at least a first state and a second state;

in the first state, the heat source is off, and the temperature of the shape memory alloy is a first temperature T1;

in the second state, the heat source is turned on, the heat storage part releases heat to the shape memory alloy, and the temperature of the shape memory alloy is a second temperature T2, wherein T1 < T2.

7. The foldable display device of claim 5,

the heat storage part comprises a heat storage pipe, and a phase change heat storage material and/or an adsorption heat storage material are/is arranged in the heat storage pipe.

8. The foldable display device of claim 5,

the temperature adjusting part comprises at least two heat storage parts, and the bending area is positioned between the two heat storage parts.

9. The foldable display device of claim 5,

one side of the supporting part, which is far away from the flexible display panel, comprises a first groove, the heat storage part is positioned in the first groove, and the heat storage part is attached to the supporting part.

10. The foldable display device of claim 5, further comprising:

a first heat-conducting portion; the first heat conduction portion is located between the heat storage portion and the shape memory alloy.

11. The foldable display device of claim 5, further comprising:

a second heat conduction portion; the second heat conduction portion is located between the driving chip and the heat storage portion, and/or the second heat conduction portion is located between the power supply and the heat storage portion.

12. The foldable display device of claim 5,

the temperature adjusting part further includes:

the inner wall of the first radiating pipe is provided with an electromagnetic pump, and the electromagnetic pump is electrically connected with the induction controller;

liquid metal is filled in the first radiating pipe, and the liquid metal flows under the action of the electromagnetic pump.

13. The foldable display device of claim 12,

the foldable display device comprises at least a first state, a second state and a third state;

in the first state, the heat source is turned off, the electromagnetic pump is turned on, the liquid metal circularly flows under the action of the electromagnetic pump, and the temperature of the shape memory alloy is a third temperature T3;

in the second state, the heat source is turned on, the electromagnetic pump is turned off, the heat storage part releases heat to the shape memory alloy, and the temperature of the shape memory alloy is a fourth temperature T4;

in the third state, the heat source is turned on, the electromagnetic pump is turned off, the heat storage part releases heat to the shape memory alloy, and the temperature of the shape memory alloy is a fifth temperature T5; t3 < T4 < T5.

14. The foldable display device of claim 12,

the first radiating pipe is located on one side, close to the bending area, of the heat storage portion.

15. The foldable display device of claim 12, further comprising:

the functional film layer is positioned on one side of the flexible display panel;

the glue material is positioned between the flexible display panel and the functional film layer; the material of the rubber material comprises shape memory polymer.

16. The foldable display device of claim 15,

the bending area comprises a first sub-bending area and a second sub-bending area, and the first sub-bending area is positioned on one side of the second sub-bending area, which is close to the heat storage part; the first sub-bending area is positioned on one side of the second sub-bending area close to the first radiating pipe;

the mass fraction of the shape memory polymer in the first sub-inflection region is greater than the mass fraction of the shape memory polymer in the second sub-inflection region.

17. The foldable display device of claim 1,

the material of the supporting part positioned in the non-bending area comprises one or more of wood, bakelite, PVC, PP, PE and ABS;

the supporting part located in the non-bending area and the supporting part located in the bending area are spliced into a whole.

18. The foldable display device of claim 1,

the thicknesses of the supporting parts at different positions of the non-bending area are the same.

[ background of the invention ]

With the continuous development of display technology, various display products with different characteristics are produced to meet different use requirements. A foldable display device is a novel display product with flexibility. The foldable display device can be realized in different folded states. The user can fold the foldable display device as required to reduce the space occupied by the foldable display device, so as to be convenient for storage and carrying. The user can also unfold the foldable display device to realize large-area display of the foldable display device. At present, after the foldable display device is bent for multiple times, the folding area of the foldable display device cannot be naturally restored to the flat state, obvious creases are easily generated in the folding area, and the speed of restoring the creases to the flat state is very slow, so that the user experience is influenced.

[ summary of the invention ]

Embodiments of the present invention provide a foldable display device to eliminate or reduce a crease in the foldable display device.

An embodiment of the present invention provides a foldable display device, including:

a flexible display panel;

the supporting component is positioned on one side of the flexible display panel, which is deviated from the light emergent side; the support assembly comprises a support part and a temperature adjusting part; the temperature adjusting part is positioned on one side of the supporting part far away from the flexible display panel;

the supporting part comprises a bending area and a non-bending area, the material of the supporting part positioned in the bending area comprises shape memory alloy, and the supporting part positioned in the bending area comprises a hollow part;

the orthographic projection of the temperature adjusting part on the plane of the supporting part is located in the non-bending area, and the temperature adjusting part is used for adjusting the temperature of the shape memory alloy.

According to the foldable display device provided by the embodiment of the invention, the support part positioned in the bending area is provided with the hollow part, so that the bending stress of the support part in the bending process can be released, the stress concentration is avoided, and the possibility of cracks in the support part is reduced. In addition, the support part positioned in the bending area is formed by adopting the shape memory alloy, the temperature adjusting part for adjusting the temperature of the shape memory alloy is arranged in the support assembly, and when the foldable display device is switched between different folding states, the shape memory alloy can be quickly restored to the memory shape matched with the folding state of the foldable display device through the temperature adjusting function of the temperature adjusting part. Moreover, under the driving of the supporting component, other parts in the foldable display device can also be perfectly matched with various folding states required to be realized by the foldable display device, and unevenness phenomena such as creases, stamping marks, folds and the like of a bending area of the foldable display device can be reduced or even eliminated.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic cross-sectional view of a foldable display device in an unfolded state according to an embodiment of the present invention;

fig. 2 is a schematic top view of a supporting portion according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of a support portion according to an embodiment of the present invention;

fig. 4 is a schematic diagram illustrating a folding state of a foldable display device according to an embodiment of the present invention;

fig. 5 is a schematic view illustrating a folded state of another foldable display device according to an embodiment of the present invention,

fig. 6 is a schematic diagram of a relative position relationship between a driving chip, a power supply, an inductive controller and a backplane assembly according to an embodiment of the present invention;

FIG. 7 is a schematic top view of a support assembly according to an embodiment of the present invention;

FIG. 8 is a schematic cross-sectional view of a support assembly according to an embodiment of the present invention;

FIG. 9 is a schematic top view of another support assembly provided in accordance with an embodiment of the present invention;

FIG. 10 is a schematic top view of another support assembly provided in accordance with an embodiment of the present invention;

FIG. 11 is a schematic cross-sectional view of another support assembly provided in accordance with an embodiment of the present invention;

FIG. 12 is a schematic top view of another support assembly provided in accordance with an embodiment of the present invention;

FIG. 13 is a schematic top view of another support assembly provided in accordance with an embodiment of the present invention;

FIG. 14 is a schematic top view of another support assembly provided in accordance with an embodiment of the present invention;

FIG. 15 is a simulated view of the bending profile of the support portion having four configurations as shown in FIGS. 2, 12, 13 and 14, respectively, in a first state;

fig. 16 is a simulation graph of elastic modulus at different positions of the support portions respectively having the four structures shown in fig. 12, 13 and 14;

fig. 17 is a schematic cross-sectional view of another support assembly according to an embodiment of the present invention.

Fig. 18 is a schematic cross-sectional view of a rubber material according to an embodiment of the present invention.

Fig. 19 is a schematic top view of a rubber material according to an embodiment of the present invention.

[ detailed description ] embodiments

For better understanding of the technical solutions of the present invention, the following detailed descriptions of the embodiments of the present invention are provided with reference to the accompanying drawings.

It should be understood that the described embodiments are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

An embodiment of the present invention provides a foldable display device, as shown in fig. 1, fig. 1 is a schematic cross-sectional view of the foldable display device provided in an embodiment of the present invention in an unfolded state, and the foldable display device 100 includes a bending region a1 and a non-bending region a 2. Under the action of external force, the bending region a1 can be bent, so that the foldable display device 100 can assume different folding states to meet the corresponding requirements of users.

As shown in fig. 1, the foldable display device 100 includes a flexible display panel 1 and a support member 2.

Wherein the flexible display panel 1 comprises a plurality of light emitting cells having different colors. Illustratively, the light emitting unit includes any one or more of an organic light emitting device, a micro light emitting diode device, and a quantum dot light emitting device. As shown in fig. 1, the flexible display panel 1 includes a first surface 11 and a second surface 12 that are oppositely disposed in a thickness direction of the flexible display panel 1. The side of the first surface 11 may be a light exit side of the flexible display panel 1. The side of the second surface 12 may be the non-light emitting side of the flexible display panel 1.

With continued reference to fig. 1, in the embodiment of the present invention, the supporting member 2 is located at the non-light-emitting side of the flexible display panel 1. I.e. the support element 2 is located on the side of the second surface 12 remote from the first surface 11.

In the present embodiment, the support assembly 2 includes a support portion and a temperature adjusting portion. The support portion is used to support the flexible display panel 1. Moreover, when the foldable display device 100 is switched between different folded states, the supporting portion may drive other structures including the flexible display panel 1 in the foldable display device 100 to bend.

As shown in fig. 2 and 3, fig. 2 is a schematic top view of a supporting portion according to an embodiment of the present invention, fig. 3 is a schematic cross-sectional view of a supporting portion according to an embodiment of the present invention, and the supporting portion 21 located in the bending area a1 includes a hollow portion 210. As shown in fig. 3, the hollowed-out portion 210 penetrates the support portion 21 in the thickness direction of the support portion 21. The arrangement of the hollow-out part 210 can release the bending stress of the support part 21 in the bending process, avoid stress concentration and reduce the possibility of cracks in the support part 21. Alternatively, the hollow portion 210 may have a cylindrical shape, a strip shape, a saw-tooth shape, a wavy shape, or the like.

In the present embodiment, the material of the support portion 21 at the bending region a1 includes a shape memory alloy. Shape memory alloys refer to alloys that have an initial shape that can be restored to the initial shape by heating above a certain critical temperature after being deformed at a low temperature and set to another shape. The function that a shape memory alloy has to be able to remember its original shape is called shape memory effect. The initial shape of the shape memory alloy is defined below as the memorized shape. The temperature at which the shape of the shape memory alloy returns to the memorized shape is defined as the memorizing temperature.

The shape memory alloy is composed of more than two metal elements according to a certain weight ratio. Shape memory alloys are typically prepared by first preparing an alloy ingot and then performing a shape memory process, including some heat treatment, to achieve the shape memory function of the alloy. Illustratively, in embodiments of the present invention, the shape memory alloy comprises a two-way shape memory alloy or a one-way shape memory alloy.

The one-way shape memory alloy has a memorized shape. After the one-way shape memory alloy is deformed under the action of an external load, if the one-way shape memory alloy is heated, the temperature of the one-way shape memory alloy is raised to the memory temperature, and the shape of the one-way shape memory alloy is restored to the memory shape.

By two-way shape memory alloy is meant that the shape memory alloy has two memorized shapes, a high temperature phase memorized shape and a low temperature phase memorized shape. After the two-way shape memory alloy deforms under the action of an external load, if the temperature of the two-way shape memory alloy is changed, the two-way shape memory alloy can recover a high-temperature phase memory shape when the two-way shape memory alloy is heated; upon cooling of the two-way shape memory alloy, the two-way shape memory alloy will return to the low temperature phase memory shape.

In the embodiment of the present invention, when designing the foldable display device 100, a suitable shape memory alloy material and a suitable processing technique may be selected according to a desired folded state of the foldable display device 100, so that the shape memory alloy has a one-way or two-way memory effect, and the shape memory alloy can have a memory shape matching a common folded state of the foldable display device 100, so that the deformation of the support portion 21 during the bending process can match different folded states of the foldable display device 100.

For example, when the foldable display device 100 is required to be bent at 0-180 °, and it is desired that the foldable display device 100 has two folding states as shown in fig. 1 and fig. 4, fig. 4 is a schematic folding state diagram of a foldable display device according to an embodiment of the present invention, in which a single-pass shape memory alloy may be selected to form the support portion located in the bending region a 1. Here, the bending angle refers to an included angle between two adjacent non-bending regions a2 of the foldable display device 100. When the foldable display device 100 has a 0 ° bending angle as shown in fig. 4, the flexible display panel is folded to the inside of the foldable display device 100. For the sake of clarity, the folded state shown in fig. 4 is hereinafter defined as a first state of the foldable display apparatus 100, and the folded state shown in fig. 1 is hereinafter defined as a second state of the foldable display apparatus 100.

Optionally, when designing the one-way shape memory alloy, the embodiment of the invention may match the memory shape of the one-way shape memory alloy with the shape of one common state in the 0-180 ° bending state. For example, the memory shape of the one-way shape memory alloy may correspond to a shape with a bend angle of 180 °, i.e., a shape in which the foldable display device 100 is in the second state shown in fig. 1.

For example, the shape memory alloy may be formed by selecting a titanium-nickel alloy, a nickel-aluminum alloy, a copper-zinc-aluminum alloy, and the like, and combining the selected materials with a suitable processing technique. Optionally, when the titanium-nickel alloy is selected, the weight fraction w of nickel in the titanium-nickel alloy may satisfy: 45% w 55%, and matching the cold working and solution aging heat treatment processes such that the one-way shape memory alloy has a memorized shape corresponding to the shape in the second state shown in figure 1.

When the foldable display device 100 is required to be folded at 0-360 degrees, and it is desired that the foldable display device 100 has a folded state as shown in fig. 5 in addition to the folded states shown in fig. 1 and fig. 4, fig. 5 is a schematic folded state diagram of another foldable display device provided in an embodiment of the present invention, and the folded shape shown in fig. 5 is defined as a third state of the foldable display device 100, in an embodiment of the present invention, a two-way shape memory alloy may be selected to form a support portion located in the folding area a1, and two memory shapes of the two-way shape memory alloy are respectively matched with two common shapes of the 0-360 degrees folded states.

As shown in fig. 5, when the folding angle of the foldable display device 100 is 360 °, the flexible display panel is folded to the outside of the foldable display device 100. For example, the embodiment of the invention may make the low temperature phase memory shape of the two-way shape memory alloy correspond to a bending angle of 0 °, i.e. the shape of the foldable display device 100 in the first state shown in fig. 4, and make the high temperature phase memory shape of the two-way shape memory alloy correspond to a bending angle of 360 °, i.e. the shape of the foldable display device 100 in the third state shown in fig. 5.

Optionally, in the embodiment of the present invention, a suitable processing technology may be used to form the two-way shape memory alloy by selecting a titanium-nickel alloy, a nickel-aluminum alloy, a copper-zinc-aluminum alloy, and the like. When selecting the titanium-nickel alloy, the embodiment of the invention can select the titanium-nickel alloy and match with a proper processing technology to form the shape memory alloy. Optionally, in the embodiment of the present invention, the weight fraction w of nickel in the titanium-nickel alloy may satisfy: w is more than or equal to 40% and less than or equal to 60%, and the shape memory heat treatment is matched with a certain high temperature, wherein the temperature T for carrying out the shape memory heat treatment can satisfy the following conditions: t is between 400 and 500 ℃, so that the low-temperature phase memory shape of the two-way shape memory alloy corresponds to the shape in the first state shown in figure 4, and the high-temperature phase memory shape of the two-way shape memory alloy corresponds to the shape in the third state shown in figure 5.

It should be noted that the above-mentioned selection of the one-way shape memory alloy to form the foldable display device 100 having a bending angle of 0 to 180 degrees is only an illustration, and when the foldable display device 100 needs to be bent at 0 to 180 degrees, the embodiment of the present invention may also select the two-way shape memory alloy to form the support portion 21 located in the bending region a1, and make the low-temperature phase memory shape of the two-way shape memory alloy correspond to the shape shown in fig. 4, and make the high-temperature phase memory shape of the two-way shape memory alloy correspond to the shape shown in fig. 1.

In an embodiment of the present invention, the temperature regulating portion is used to regulate the temperature of the shape memory alloy. The orthographic projection of the temperature adjusting part on the plane of the supporting part 21 is positioned in the non-bending area A2 so as to avoid the temperature adjusting part from being influenced by bending stress.

In the process of applying a load to the foldable display device 100 when adjusting the folded state of the foldable display device 100, the temperature adjusting part may adjust the temperature of the shape memory alloy according to the load applied to the foldable display device 100, so that the shape memory alloy may be rapidly restored to a memory shape matched with the folded state of the foldable display device 100.

It can be seen that the foldable display device 100 according to the embodiment of the present invention uses the shape memory alloy to form the supporting portion 21 located in the bending region a1, and the temperature adjusting portion for adjusting the temperature of the shape memory alloy is disposed in the supporting assembly, so that when the foldable display device 100 is switched between different folding states, the shape memory alloy can be rapidly restored to the memory shape matched with the folding state of the foldable display device 100 by the temperature adjusting function of the temperature adjusting portion. Moreover, under the driving of the supporting component 2, other components in the foldable display device 100 can also be perfectly matched with various folding states that the foldable display device 100 needs to realize, which is beneficial to reducing or even eliminating unevenness such as creases, impressions, folds and the like of the foldable display device 100.

Exemplarily, the temperature adjusting part includes an induction controller and a heat source; the induction controller is electrically connected with the heat source; the heat source is used to increase the temperature of the shape memory alloy. The heat source can provide the energy guarantee required by the shape memory alloy to restore the memorized shape. The sensing controller is used to sense an applied load applied to the foldable display device 100 and to control the turning on and off of the heat source according to the applied load.

When external force is applied to switch the foldable display device 100 from one folding state to another folding state, the induction controller judges that the shape memory alloy needs to be heated according to the external load applied to the foldable display device 100, the induction controller controls the heat source to be started, and when the temperature of the shape memory alloy reaches the memory temperature, the shape memory alloy recovers the memory shape.

Optionally, in the embodiment of the present invention, the sensing controller and the heat source may be both located at a side of the supporting portion 21 away from the flexible display panel 1; the temperature of the shape memory alloy is adjusted as required, and the flexible display panel 1 can be prevented from being influenced while the memory shape is rapidly recovered.

Illustratively, the orthographic projection of the induction controller on the plane of the support part 21 and the orthographic projection of the heat source on the plane of the support part 21 are both located in the non-bending area A2.

As shown in fig. 1, the foldable display device 100 further comprises a back plate assembly 3, wherein the back plate assembly 3 is located at a side of the support assembly 2 away from the flexible display panel 1.

Illustratively, the foldable display device 100 further includes a driving chip 4 and a power supply 5. The driving chip 4 is electrically connected to signal lines including data lines and scanning lines in the flexible display panel 1 to supply signals for display to the flexible display panel 1.

Referring to fig. 6, fig. 6 is a schematic diagram of a relative position relationship between a driving chip, a power supply, an induction controller and a backplate assembly according to an embodiment of the present invention, where the driving chip 4, the power supply 5 and the induction controller 221 are all located on one side of the backplate assembly 3 close to the support assembly 2. The backplane assembly 3 may serve as a carrier for carrying the above components, and the backplane assembly 3 may also serve as a protection for the flexible display panel 1. As shown in fig. 6, the orthographic projection of the driving chip 4, the power source 5 and the sensing controller 221 is located at the non-bending region a 2.

In the embodiment of the invention, at least one of the power supply 5 and the driving chip 4 can be electrically connected with the induction controller; and/or, at least one of the power supply 5 and the driving chip 4 is reused as a heat source for heating the shape memory alloy. When the flexible display panel 1 displays, the driving chip 4 and the power supply 5 operate. The driver chip 4 and the power supply 5 generate heat during operation. In the embodiment of the present invention, at least one of the power supply 5 and the driving chip 4 can be reused as a heat source for heating the shape memory alloy, and the heat generated by the driving chip 4 and/or the power supply 5 can heat the shape memory alloy to the memory temperature to realize the required deformation.

Exemplarily, when the bending angle of the foldable display device 100 is 0 °, that is, when the foldable display device 100 is in the first state shown in fig. 4, since the flexible display panel 1 is folded to the inner side of the foldable display device 100, the embodiment of the invention may make the first state correspond to a standby state in which the flexible display panel 1 does not perform display. When the bending angle of the foldable display device 100 is 180 ° and 360 °, that is, when the foldable display device 100 is in the second state shown in fig. 1 and the third state shown in fig. 5, respectively, the embodiment of the invention can make both the second state and the third state correspond to the display state displayed by the flexible display panel 1.

When the shape memory alloy has a memory shape corresponding to at least one of the first state, the second state, and the third state, for example, when the shape memory alloy is used in a single-pass memory shape, the embodiment of the invention may make the memory shape correspond to the second state or the third state in which the flexible display panel 1 performs display. When the shape memory alloy is a two-way memory shape alloy, the embodiment of the invention can make the high-temperature phase memory shape correspond to the second state or the third state displayed by the flexible display panel 1. In this way, the shape memory alloy can be heated by the heat generated by the electronic devices including the driving chip 4 and the power supply 5 during the operation of the flexible display panel 1, and an additional heat source in the foldable display device 100 is avoided.

Taking the one-way shape memory alloy as an example, when the foldable display device 100 is in the first state shown in fig. 4, the flexible display panel 1 is folded to the inside of the foldable display device 100, the flexible display panel 1 is in the standby state, the power supply 5 and the driving chip 4 do not work, and both do not generate heat, so the shape memory alloy has a lower temperature. When the foldable display device 100 is changed from the first state shown in fig. 4 to the second state shown in fig. 1, the flexible display panel 1 is in the display state, and the power supply 5 and the driving chip 4 are both operated to generate heat. This heat can be transferred to the shape memory alloy, causing the shape memory alloy to heat up to a remembered temperature, thereby allowing the shape memory alloy to quickly return to a remembered shape.

Optionally, in the preparation of the one-way shape memory alloy, the embodiment of the invention can enable the memory temperature T to be higher than the temperature T of the other one-way shape memory alloy₀₁Satisfies the following conditions: t is not less than 30 DEG C₀₁≤40℃。

Alternatively, as shown in fig. 7, fig. 7 is a schematic top view of a supporting assembly according to an embodiment of the present invention, and the temperature regulating portion further includes a heat storage portion 6. The heat storage portion 6 is for storing heat emitted from a heat source including a driving chip (not shown in fig. 7) and a power supply (not shown in fig. 7).

When the power source 5 and the driving chip 4 need to drive the flexible display panel 1 for displaying, but the sensing controller 221 senses that the shape memory alloy needs to be at a low temperature according to a load applied to the foldable display device 100, the heat storage portion 6 may store heat emitted by at least one of the power source 5 and the driving chip 4 as a power supply module and a driving module during operation. When the sensing controller 221 senses that a high temperature is required for the shape memory alloy according to a load applied to the foldable display device 100, the heat storage part 6 may release heat stored therein to the shape memory alloy to heat the shape memory alloy to a temperature required for deformation.

It should be noted that, in the embodiment of the present invention, the heat storage process of the heat storage portion 6 may be performed spontaneously, and as long as the temperature outside the heat storage portion 6 is higher than the temperature inside the heat storage portion, the external heat can be conducted into the heat storage portion 6 through heat conduction and stored by the heat storage portion 6. In other words, the heat storage operation of the heat storage unit 6 may be performed not only at the time when the flexible display panel 1 displays but the shape memory alloy requires a low temperature, but also at the time when the flexible display panel 1 does not display and the shape memory alloy requires a low temperature; and the flexible display panel 1 shows the moment when the shape memory alloy requires a high temperature.

Illustratively, the heat source further comprises a flexible display panel. When the flexible display panel displays, each electronic device therein also generates heat, and this heat can also be stored by the heat storage portion 6.

When a load is applied to the foldable display device 100 to change the foldable display device 100 to the folded state, taking as an example that the support portion 21 located in the folding region a1 is made of a one-way shape memory alloy, and the folded state of the foldable display device 100 includes at least the first state shown in fig. 4 and the second state shown in fig. 1, in the process of switching the foldable display device 100 from the second state to the first state by an external load and maintaining the first state, the induction controller 221 controls the heat source to be turned off to make the temperature of the shape memory alloy be the first temperature T1 which is relatively low, so that the phase state of the shape memory alloy is the low-temperature martensite phase. For example, the first temperature T1 may be room temperature.

During the switching of the foldable display device 100 from the first state to the second state by the applied load and the maintaining of the second state, the sensing controller 221 controls the heat source to be turned on, so that the temperature at which the shape memory alloy is located is increased to a second higher temperature T2, T1 < T2. At a second temperature T2, the internal structure of the shape memory alloy reverts to the high temperature phase austenite phase and the macroscopic shape of the shape memory alloy reverts to the memory shape. At this temperature, the shape memory alloy exhibits superelasticity, which eliminates previous fold marks.

Illustratively, in the embodiment of the present invention, the heat storage unit 6 is electrically connected to the induction controller 221. The heat release action of the heat storage part 6 may be controlled by the sensing controller 221 according to the load applied to the foldable display device 100.

As shown in fig. 6 and 7, the foldable display device 100 further includes a heat storage terminal 60 and an induction terminal 2210. The heat storage terminal 60 is connected to the heat storage unit 6. The sensing terminal 2210 is electrically connected to the sensing controller 221. The embodiment of the present invention realizes the electrical connection of the heat storage part 6 and the induction controller 221 through the electrical connection of the heat storage terminal 60 and the induction terminal 2210.

Exemplarily, in the present embodiment, the temperature adjusting portion includes at least two heat storage portions 6. As shown in fig. 7, two of the heat storage portions 6 are respectively located in two non-bending regions a2 on both sides of the bending region a 1. So set up, can make the shape memory alloy that is located kink A1 receive the heat that heat storage portion 6 transmitted respectively from both sides to can make the quick intensification of shape memory alloy when needing high temperature, quick memory form that reaches.

In the embodiment of the present invention, the heat storage portion 6 stores the heat released by the driving chip 4 or the power supply 5 at the stage when the shape memory alloy does not need to be heated, and the heat is released when the shape memory alloy needs to be heated, so that the existing components in the foldable display device 100 can be fully utilized, and the heat released by each electronic device including the power supply 5 and the driving chip 4 at each working stage can be utilized, and thus, while ensuring that the shape memory alloy realizes the required deformation, no new component needs to be added, which is beneficial to reducing the number of components in the foldable display device 100, reducing the structural complexity of the foldable display device 100, and reducing the production cost of the foldable display device 100.

In addition, in the embodiment of the present invention, the orthographic projection of the heat storage portion 6 on the plane of the support portion 21 may be located between the orthographic projection of the driving chip 4 on the plane of the support portion 21 and the shape memory alloy, and/or the orthographic projection of the heat storage portion 6 on the plane of the support portion 21 may be located between the orthographic projection of the power supply 5 on the plane of the support portion 21 and the shape memory alloy.

With reference to fig. 6 and 7, it is shown that the foldable display device 100 includes two heat storage portions 6, wherein the orthographic projection of one heat storage portion 6 on the plane of the supporting portion 21 is located between the orthographic projection of the driving chip 4 on the plane of the supporting portion 21 and the shape memory alloy, and the orthographic projection of the other heat storage portion 6 on the plane of the supporting portion 21 is located between the orthographic projection of the power supply 5 on the plane of the supporting portion 21 and the shape memory alloy, and with the above arrangement, the driving chip 4 and the power supply 5 can be arranged at a greater distance from the bending region a1, so as to ensure that the driving chip 4 and the power supply 5 are not affected by bending. Moreover, the heat storage unit 6 may also serve as a heat conduction structure between the driving chip 4 and the shape memory alloy and a heat conduction structure between the power supply 5 and the shape memory alloy, so that the loss of heat generated by the power supply 5 and the driving chip 4 in the process of conducting the heat to the shape memory alloy can be reduced, and the heat transfer efficiency can be improved.

For example, the embodiment of the present invention may make the heat storage portion 6 of a material having flexibility.

Optionally, the heat storage portion 6 includes a heat storage pipe, and a heat storage material is disposed in the heat storage pipe. In an embodiment of the present invention, the heat storage material includes a phase change heat storage material and/or an adsorption heat storage material.

The phase-change heat storage material comprises at least one or more of molten salt, mixed salt, metal or alloy, calcium chloride hexahydrate, sodium acetate trihydrate and organic alcohol. The phase change heat storage material stores and utilizes heat by utilizing phase change heat of substances in a phase change process. The embodiment of the invention can store heat by utilizing the latent heat of fusion of the phase-change heat storage material in the change process between the solid phase and the liquid phase. Furthermore, when the sensing controller determines that the shape memory alloy requires a high temperature based on the load applied to the foldable display device 100, the phase change heat storage material may undergo a reverse phase change, in which process heat is released to the shape memory alloy disposed adjacent to the heat storage tube.

The adsorption heat storage material comprises zeolite or silica gel. The adsorptive heat storage material includes a fluid phase and solid particles, and adsorption occurs when the fluid phase contacts the solid particles. The surface of the solid particles as the adsorbent is not uniform, and the adsorption heat storage material absorbs the environmental energy at this time with the generation of adsorption heat. When the sensing controller 221 determines that the shape memory alloy needs a high temperature based on the load applied to the foldable display device 100, the sensing controller 221 releases the stimulus to the heat storage portion 6, and the adsorbed heat storage material is desorbed by the applied stimulus, thereby releasing the heat to the shape memory alloy disposed near the heat storage tube.

Exemplarily, as shown in fig. 8, fig. 8 is a schematic cross-sectional view of a support assembly according to an embodiment of the present invention, a side of the support portion 21 away from the flexible display panel includes a first groove 211, and the heat storage portion 6 is located in the first groove 211 to reduce an overall thickness of the foldable display device 100.

Optionally, in the embodiment of the present invention, the heat storage portion 6 may be attached to the support portion 21. In the embodiment of the present invention, the depth of the first groove 211 is smaller than the thickness of the supporting portion 21. So set up, can guarantee that the surface of supporting part 21 and the laminating of flexible display panel 1 is the plane to the laminating of supporting part 21 and flexible display panel 1 is convenient for.

It should be noted that the specific shape and size of the heat storage portion 6 are not limited in the embodiment of the present invention, and the shape of the orthographic projection of the heat storage portion 6 on the plane where the supporting portion 21 is located in fig. 7 is only a schematic illustration, actually, the heat storage portion 6 may be set to be wavy or other irregular figures in the embodiment of the present invention, and the sizes of the heat storage portion 6 in different directions may be designed accordingly according to actual requirements.

Illustratively, the support assembly 2 further comprises a first heat-conducting portion; the first heat conduction portion is located between the heat storage portion 6 and the shape memory alloy. The first heat conducting part can conduct heat released by the heat storage part 6 to the shape memory alloy better, so that the loss of the heat in the transmission process is reduced, and the heat transfer efficiency is improved. For example, the first heat conducting portion may be made of a metal material with good heat conductivity, such as copper foil or stainless steel.

For example, as shown in fig. 9, fig. 9 is a schematic top view of another supporting assembly according to an embodiment of the present invention, where the supporting assembly 2 further includes a second heat conducting portion 231; the second heat conduction portion 231 is located between the driving chip 4 and the heat storage portion 6; and/or the second heat conducting portion 231 is located between the power source 5 and the heat storage portion 6. The second heat conduction part 231 can better conduct heat emitted by the driving chip 4 and/or the power supply 5 to the heat storage part 6, so that the loss of heat in the transmission process can be reduced, and the heat transfer efficiency can be improved. For example, the first heat conducting portion may be made of a metal material with good heat conductivity, such as copper foil or stainless steel.

Alternatively, when the support portion 21 located in the bending region a1 is formed by using two-way shape memory, as shown in fig. 10, fig. 10 is a schematic top view of another support assembly according to an embodiment of the present invention, and the temperature adjustment portion further includes a first heat pipe 71, where the first heat pipe 71 is used for reducing the temperature of the shape memory alloy. An electromagnetic pump is arranged on the inner wall of the first radiating pipe 71 and is electrically connected with the induction controller 221; the first radiating pipe 71 is filled with liquid metal, and the liquid metal flows under the action of the electromagnetic pump. The liquid metal flows to absorb heat, so that the temperature of the two-way shape memory alloy can be reduced to the temperature required by the low-temperature phase memory shape, and the two-way shape memory alloy can be quickly restored to the low-temperature phase memory shape. Illustratively, the liquid metal is liquid at the low temperature memory temperature of the two-way shape memory alloy. The liquid metal comprises one or more of gallium, rubidium and cesium.

When the foldable display device 100 is switched from one folded state to another folded state by applying a load, the sensing controller 221 may instruct the heat source to be turned off and the electromagnetic pump in the first heat pipe 71 to start operating to reduce the temperature of the shape memory alloy when the shape memory alloy required for the switched folded state has a low memory temperature.

Illustratively, when the shape memory alloy has a memory shape corresponding to at least one of the first state, the second state, and the third state, for example, when a two-way shape memory alloy is used, the embodiment of the present invention may make the low-temperature phase memory shape of the two-way shape memory alloy correspond to the first state that the flexible display panel 1 does not display. The high temperature phase memory shape of the two-way shape memory alloy corresponds to the third state displayed by the flexible display panel 1. With this arrangement, on the one hand, the shape memory alloy can be heated to the high temperature phase memory temperature by the heat generated by the electronic devices including the driving chip 4 and the power supply 5 during the operation of the flexible display panel 1, thereby avoiding an additional heat source in the foldable display device 100. On the other hand, when the shape memory alloy is cooled to the low-temperature phase memory temperature, because the flexible display panel 1 does not display, and each electronic device including the driving chip 4 and the power supply 5 does not work and does not generate heat, compared with the flexible display panel 1 during working, the cooling range can be reduced, and the rapid cooling is facilitated.

Optionally, when the two-way shape memory alloy is prepared, the embodiment of the invention can enable the memory temperature T corresponding to the low-temperature phase memory shape to be higher than the memory temperature T corresponding to the low-temperature phase memory shape₀₂Satisfies the following conditions: t is not less than 10 DEG C₀₂Is less than or equal to 20 ℃. Memory temperature T corresponding to high-temperature phase memory shape₀₃Satisfies the following conditions: t is not less than 30 DEG C₀₃≤40℃。

When the foldable display device 100 is changed to the folded state by applying a load to the foldable display device 100, taking as an example that the support portion 21 located in the bending region a1 is made of a two-way shape memory alloy, the folded state of the foldable display device 100 at least includes the first state shown in fig. 4, the second state shown in fig. 1 and the third state shown in fig. 5, during the switching of the foldable display device 100 from the second state to the first state by applying an external load and the maintaining of the first state, the sensing controller 221 controls the heat source to be turned off and controls the electromagnetic pump in the first radiating pipe 71 to be turned on, the liquid metal circulates under the action of the electromagnetic pump, and the temperature of the shape memory alloy is the third temperature T3.

During the switching of the foldable display device 100 from the first state to the second state by the applied load and the maintaining of the second state, the sensing controller 221 controls the heat source to be turned on and controls the electromagnetic pump in the first radiating pipe 71 to be turned off, so that the temperature of the shape memory alloy is raised to the fourth temperature T4. At a fourth temperature T4, the shape memory alloy is in the transition phase R phase. The transition phase R phase is a phase between the martensite phase and the austenite phase. The shape of the shape memory alloy is transformed into a transition state whose morphology changes with an applied load.

During the switching of the foldable display device 100 from the second state to the third state by the applied load and the maintaining of the third state, the sensing controller 221 controls the heat source to be turned on, the electromagnetic pump in the first radiating pipe 71 is turned off, and the temperature of the shape memory alloy is set to the fifth temperature T5; t3 < T4 < T5. At a fifth temperature T5, the shape memory alloy is in the austenite phase and the shape memory alloy returns to the high temperature phase memory state and exhibits superelasticity.

For example, when the first heat pipe 71 is disposed, as shown in fig. 10, the embodiment of the invention may dispose the first heat pipe on a side of the heat storage portion 6 close to the bending region a1 to ensure the heat dissipation effect on the shape memory alloy.

Optionally, in the embodiment of the present invention, the pipe wall of the first heat dissipation pipe 71 may be made of a bendable flexible material, so as to ensure the reliability of the foldable display device 100 in the bending process.

Exemplarily, as shown in fig. 11, fig. 11 is a schematic cross-sectional view of another supporting assembly according to an embodiment of the present invention, a side of the supporting portion 21 away from the flexible display panel 1 further includes a second groove 212, and the first heat dissipation pipe 71 is located in the second groove 212 to reduce the thickness of the foldable display device 100.

For example, when the supporting portion 21 is provided, as shown in fig. 3, the embodiment of the present invention may make the thickness of the supporting portion 21 located at the non-bending region a2 the same at different positions. That is, the surface of the supporting portion 21 located in the non-bending region a2 close to the flexible display panel 1 is made to be a flat surface, so as to provide a flat bearing surface for the flexible display panel 1.

Alternatively, in the first state, the supporting portion 21 located in the bending region a1 may have a shape similar to a drop shape as shown in fig. 4. The drop-shaped support portion 21 may form a screen accommodating space for accommodating the folded flexible display panel therein. The drop-shaped design may also allow the foldable display device 100 to have a shorter internal gap after being folded while avoiding dead folds of the flexible display panel.

For example, in the third state, the support portion 21 located in the bending region a1 may have an approximately U-shape as shown in fig. 5.

Optionally, in the embodiment of the present invention, a hollow portion and/or a groove may be further disposed in the supporting portion 21 located in the non-bending region a 2. The hollow and/or the groove in the non-bending area a2 can be designed to better match the shape of the water drop of the support portion 21 in the first state. For example, the hollowed-out portions and/or grooves in the non-bending region a2 may be formed by the same etching process as the hollowed-out portions 210 in the bending region a 1. The shape of the hollowed-out portions and/or the grooves in the non-bending region a2 includes a grid or a strip.

Fig. 12 and 13 are schematic top views of two other support assemblies provided by the embodiment of the present invention, as shown in fig. 12 and 13, respectively, in fig. 12, the support portion 21 located at the non-bending region a2 includes a strip-shaped groove 2101, and the strip-shaped groove 2101 does not penetrate through the support portion 21. In fig. 13, the supporting portion 21 located in the non-bending region a2 includes a grid-shaped hollow-out portion 2102, and the grid-shaped hollow-out portion 2102 penetrates through the supporting portion 21.

Illustratively, as shown in fig. 12 and 13, the support portion 21 further includes a flat region A3, and the flat region A3 is located between the inflection region a1 and the non-inflection region a 2. In the flat area a3, the support portion 21 has no hollowed-out or grooved design. The thickness of the support portion 21 is the same at each position of the flat area a 3.

Fig. 14 is a schematic top view of another supporting assembly provided by an embodiment of the present invention, as shown in fig. 14, a supporting portion 21 located in a non-bending region a2 includes a strip-shaped groove 2101, and the strip-shaped groove 2101 does not penetrate through the supporting portion 21. In fig. 14, inflection region a1 and non-inflection region a2 are disposed adjacently without including a flat region therebetween.

In the embodiment of the present invention, the bending shape of the supporting portion 21 having the four structures shown in fig. 2, 12, 13 and 14 is simulated, and as a result of the simulation is shown in fig. 15, fig. 15 is a simulated view of the shape of the supporting portion 21 having the four structures in the first state, where X0 corresponds to the supporting portion having the structure shown in fig. 2, X1 corresponds to the supporting portion having the structure shown in fig. 12, X2 corresponds to the supporting portion 21 having the structure shown in fig. 13, and X3 corresponds to the supporting portion 21 having the structure shown in fig. 14, and as can be seen from fig. 15, the widths of the droplet-shaped structures represented by X1, X2 and X3 are all smaller than X0. It is shown that the embodiment of the present invention is advantageous to reduce the gap of the foldable display device 100 in the first state by providing the groove and/or the hollow-out portion in the non-bending region a 2.

In addition, the embodiments of the present invention respectively perform simulation tests on the elastic modulus of the support part 21 having the three structures shown in fig. 12, 13 and 14 at different positions, and the simulation result is shown in fig. 16, the abscissa represents the distance between the different positions in the support part 21 and the most protruded position of the water droplet, and the most protruded position of the water droplet in the three curves of X1, X2 and X3 corresponds to the center line of the inflection zone a1, which is respectively indicated by points B1, B2 and B3 in fig. 15; the ordinate represents the elastic modulus at the corresponding position, for example, the origin position in fig. 16 represents that the elastic modulus at the most protruding position of the water droplet in all three structures is 0, and as can be seen from fig. 16, in the range of 0-3 mm (bending region range), the elastic modulus of the support portion 21 in the bending region a1 is smaller in all three structures, which illustrates that the design of the hollow portion 210 in the bending region a1 can reduce the elastic modulus of the support portion 21 at the corresponding position, and is favorable for deformation of the bending region a 1. In the range of 9 mm-15 mm (the non-bending area provided with the groove and/or the hollow portion), the elastic modulus of the support portion 21 in the non-bending area a2 is also smaller, which indicates that the elastic modulus at the corresponding position can also be reduced by the design of the hollow portion or the groove in the non-bending area a 2.

When the supporting portion 21 is provided, for example, the embodiment of the present invention may make the supporting portion 21 located in the non-bending region a2 be made of shape memory alloy. With this arrangement, on the one hand, the support portion 21 can be formed by an integral molding process to form the shape memory alloy at different positions. On the other hand, the efficiency of heat transfer to the shape memory alloy at bend region A1 may also be improved because of the better thermal conductivity of the shape memory alloy.

Alternatively, the support portion 21 located at the non-bending region a2 may be formed by one or more light and cheap materials including wood, bakelite, PVC, PP, PE, and ABS. And the supporting part 21 positioned in the non-bending area A2 and the supporting part 21 positioned in the bending area A1 are spliced into a whole. So set up, be favorable to reducing the cost of supporting part and alleviate the weight of supporting part.

Optionally, in the embodiment of the present invention, the supporting plates located in the bending region a1 and the non-bending region a2 may be fixedly spliced together by screws or screws, so as to ensure the overall firmness of the supporting portion 21.

Illustratively, as shown in fig. 6, the foldable display device 100 further comprises a second heat pipe 72 and a third heat pipe 73, wherein the second heat pipe 72 at least partially surrounds the driving chip 4, and the third heat pipe 73 at least partially surrounds the power supply 5; the orthographic projections of the second heat dissipation pipe 72 and the third heat dissipation pipe 73 on the back plate assembly 3 are located in the non-bending area A2; the second heat dissipation pipe 72 and the third heat dissipation pipe 73 are electrically connected with the sensing controller 221; the second and third radiating pipes 72 and 73 are provided with metal therein. When selecting the material of the metal, the following conditions are satisfied: when the temperature is lower than the preset temperature, the metal is in a solid state. When the temperature is higher than the preset temperature, the metal is in a liquid state. The preset temperature can be set according to the required heat dissipation temperature of the power supply 5 and the driving chip 4. For example, in the embodiment of the present invention, a metal material with a liquefaction temperature slightly higher than the required heat dissipation temperature may be selected. So set up, when the temperature of driver chip 4 and power 5 reached demand radiating temperature, the metal material can take place solid-liquid phase change, and solid-liquid phase change is along with the heat absorption, can make the temperature of driver chip 4 and power 5 reduce, avoids the two overheated, guarantees collapsible display device 100's reliability.

Illustratively, the foldable display device 100 provided by the embodiment of the present invention further includes a cover plate 81, a buffer 82, and a hinge mechanism 83. As shown in fig. 1, the cover plate 81 is located on the light exit side of the flexible display panel 1. I.e. the cover plate 1 is located on the side of the first surface 11 remote from the second surface 12. The cover plate 1 is arranged to protect the flexible display panel 1. For example, a first adhesive 91 may be disposed between the cover plate 1 and the flexible display panel 1, and the first adhesive 91 is used for bonding the cover plate 1 and the flexible display panel 1. The material of the cover plate is preferably any one or more of a hardened PET material (HC PET), a hardened transparent polyimide film (HC CPI PET) and Ultra-Thin Glass (UTG).

As shown in fig. 1, the buffer 82 is located on the backlight side of the flexible display panel 1. That is, the buffer 82 is located on the side of the second surface 12 away from the first surface 11. The buffer 82 is provided to protect the flexible display panel 1. In the process of moving or using the foldable display device 100, if the foldable display device 100 is subjected to an external force, the buffering element 82 is configured to absorb an external stress, so as to buffer the flexible display panel 1 to a certain degree, thereby preventing the flexible display panel 1 from being affected. Illustratively, the cushioning member 82 may be foam. A second adhesive material 92 may be disposed between the buffer 82 and the flexible display panel 1, and the second adhesive material 92 is used for bonding the buffer 82 and the flexible display panel 1.

As shown in fig. 6, an orthogonal projection of the hinge mechanism 83 on the plane of the support portion 21 is located at a bending region a 1. Specifically, the embodiment of the present invention may design the hinge mechanism 83 according to the bending angle that the foldable display device 100 needs to achieve, so that the foldable display device 100 can maintain a specific bending angle under the holding force provided by the hinge mechanism 83.

Exemplarily, as shown in fig. 17, fig. 17 is a schematic cross-sectional view of a support assembly according to another embodiment of the present invention, and the foldable display device 100 further includes a flexible protection portion 84, a reinforcing sheet 85, a spacer (not shown), and a non-slip sheet 86.

The flexible protection part 84 is located on one side of the support part 21 away from the flexible display panel 1; and, the orthographic projection of the flexible protection part 84 on the plane of the support part 21 is at least partially located at the bending area a 1. The provision of the flexible protection portion 84 can provide protection to the support portion 21 located at the bending region a 1.

The reinforcing sheet 85 is positioned on one side of the supporting part 21 far away from the flexible display panel 1; and, the orthographic projection of the reinforcing sheet 85 on the plane of the supporting part 21 is at least partially located at the bending area A1. The reinforcing sheet 85 can reinforce the support of the bending region a1 of the supporting portion 21 where the hollow portion 210 is disposed, and can prevent the hinge mechanism 83 from directly contacting the flexible protection portion 84 to cause fatigue wear. Illustratively, the material of the reinforcing sheet 85 is preferably copper foil, aluminum alloy, stainless steel, or the like. The implementation process may be stamping and/or etching.

As shown in fig. 17, the anti-slip sheet 86 is located on the side of the reinforcing sheet 85 away from the flexible display panel 1; and the orthographic projection of the anti-slip sheet 86 on the plane of the supporting part 21 is at least partially positioned in the bending area A1. The anti-slip sheet 86 has a friction resistant property, and the anti-slip sheet 86 can be fitted to the hinge mechanism 83. And can intercept foreign matters from entering the flexible display panel 1 through the gap of the reinforcing sheet 85. Illustratively, the material of the anti-slip sheet 86 includes any one or more of TPU, PET, PI.

The pad is in contact with the hinge mechanism 83. The provision of the spacer can prevent the hinge mechanism 83 from contacting the recess provided on the support portion 21. Illustratively, the material of the gasket is preferably copper foil, aluminum alloy, stainless steel, or the like.

For example, in addition to the image display function, in order to enrich the use function of the foldable display device 100, the embodiment of the present invention may further provide a plurality of functional film layers with different functions in the foldable display device 100. The functional film layer may be located on a side of the first surface 11 of the flexible display panel 1 away from the second surface 12, and/or the functional film layer is located on a side of the second surface 12 away from the first surface 11. According to the functions required to be realized by the display panel, the functional film layer comprises one or more of a touch layer, a protective layer and a buffer layer. The touch layer is located on the light emitting side of the flexible display panel 1, that is, the touch layer is located on the side of the first surface 11 away from the second surface 12. The protection layer may be located on the light emitting side of the flexible display panel 1, or may be located on the backlight side of the flexible display panel 1, where the backlight side is a side of the second surface 12 away from the first surface 11. The buffer layer is located on the backlight side of the display panel.

The foldable display device 100 provided by the embodiment of the present invention further includes a glue material, and the glue material is located between the flexible display panel 1 and the functional film layer. And when the functional film layers are multi-layered, in order to improve the bonding stability between two adjacent functional film layers, an adhesive material may be disposed between two adjacent functional film layers for adhesion. As shown in fig. 1, the rubber material includes a first rubber material 91 and a second rubber material 92 shown in fig. 1.

As shown in fig. 18, fig. 18 is a schematic cross-sectional view of a rubber material according to an embodiment of the present invention, and the rubber material 90 includes a shape memory polymer 900. Shape memory polymer 900 refers to a polymer or composite material that returns to an original shape upon exposure to a temperature stimulus. Optionally, the composite material comprises at least two of a high polymer, conductive carbon black, metal powder and a conductive polymer.

In the related art, the rubber material has a recovery hysteresis. After the rubber material is folded inwards and placed for a period of time, the rubber material is flattened, and the stress borne by the rubber material is about 6 times higher than that of the glue flattened after continuous folding inwards. Therefore, when the foldable display device 100 is directly transferred from the folded-in state to the folded-out state, the pressure applied to the adhesive material is particularly high, and the deformation phenomena such as protrusion and bulge are likely to occur at the bending center, which may affect the bonding property between the films bonded by the adhesive layer. According to the embodiment of the invention, the glue material comprising the shape memory polymer is arranged, and the arrangement of the shape memory polymer can accelerate the interlayer dislocation recovery rate of the glue material, so that the problem of crease caused by the fact that the glue material cannot synchronously correspond to different folding states of the foldable display device 100 in the related technology can be solved, and the glue material can rapidly respond to the set shape no matter the folding state is kept still after being folded inwards or the folding state is directly transited from being folded inwards to being folded outwards.

In the embodiment of the present invention, when the flexible display panel 1 operates, the flexible display panel 1 may generate heat due to continuous operation. When the heat reaches the temperature required by the shape memory polymer to excite the activity, the rubber material can be quickly recovered to the initial shape. And, the closer the temperature of the glue material is to the active temperature, the faster the recovery rate is.

For example, according to the embodiment of the present invention, a suitable shape memory polymer material and a processing process thereof may be selected according to a desired folding shape of the foldable display device 100, so that the memory shape of the material matches a common folding shape of the foldable display device 100.

Exemplary types of the Adhesive material include any one of Optically Clear Adhesive (OCA) and Pressure Sensitive Adhesive (PSA). The matrix material which plays a role in bonding in the rubber material comprises any one or more of Polyethylene terephthalate (PET for short), transparent Polyimide (CPI for short), Polyimide (PI for short) and Thermoplastic polyurethane elastomers (TPU for short).

While ensuring the functions required to be realized by the functional film layer, the embodiment of the invention can also add shape memory polymer into at least part of the functional film layer to ensure that the functional film layer has no crease in the folding process. For example, in the embodiment of the invention, the shape memory polymer can be added into the buffer made of Foam (Foam), PI or TPU, so that the buffer is ensured to have no crease in the folding process.

Illustratively, the shape memory polymer includes an electro shape memory polymer and/or a thermotropic shape memory polymer.

Optionally, in the preparation process of the adhesive material, the shape memory polymer and the matrix material may be mixed and then coated on the surface of the adhesive material substrate serving as the adhesive. Alternatively, the shape memory polymer material may be directly mixed with a rubber substrate as a binder.

Fig. 19 is a schematic top view of a rubber material according to an embodiment of the present invention, as shown in fig. 19, for clearly explaining the present invention, fig. 19 shows orthographic projections of the heat storage portion 6 and the first heat dissipation tube 71 on a plane where the rubber material 90 is located, and the orthographic projections of the heat storage portion 6 and the first heat dissipation tube 71 are respectively indicated by reference numerals 6 and 71. The bending region a1 includes a first sub-bending region a11 and a second sub-bending region a12, the first sub-bending region a11 is located at a side of the second sub-bending region a12 close to the heat storage portion 6, and the first sub-bending region a11 is located at a side of the second sub-bending region a12 close to the first heat dissipation tube 71. In an embodiment of the present invention, the mass fraction of the shape memory polymer in the first sub-inflection region A11 is greater than the mass fraction of the shape memory polymer in the first sub-inflection region A12. In the embodiment of the present invention, the mass fractions of the shape memory polymers at different positions of the rubber material are set differently according to the above embodiment, so that the content of the shape memory polymers in the first sub-bending region a11, in which the temperature change of the temperature adjusting portion including the heat storage portion 6 and the first heat dissipation pipe 71 is sensitive, is higher, and the temperature adjusting portion can act on the shape memory polymers in addition to the shape memory alloy, that is, the temperature adjusting portion can be utilized to a greater extent.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.