Laminated structure, display module and electronic equipment

Abstract

The embodiment of the invention discloses a laminated structure, a display module and electronic equipment, the laminated structure is used for the display module, and the laminated structure comprises a base film, a first laminated layer and a second laminated layer which are laminated; the modulus of the second laminated layer is greater than or equal to that of the first laminated layer; wherein the first lamination layer and / or the second lamination layer are / is made of an energy-absorbing and anti-impact material, and the modulus of the energy-absorbing and anti-impact material is larger than or equal to 0.5 GPa. Therefore, the buffer layer with energy absorption and impact resistance is arranged on the inner side of the base film, so that a better buffer effect can be achieved, on one hand, the modulus of an energy absorption and impact resistance material is high, external impact stress or extrusion stress is effectively blocked, and the display module is protected against damage, and on the other hand, the energy absorption and impact resistance material is excellent in energy absorption performance, and the service life of the display module is prolonged. Impact energy or extrusion energy can be absorbed, and the buffering performance of the laminated structure is improved. And the base film, the first lamination layer and the second lamination layer are mutually matched in performance, so that the protection capability of the display module is improved.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to a stacked structure, a display module, and an electronic device. Background Technology

[0002] With the continuous development of display technology, foldable display terminals are gradually becoming a development trend for future mobile electronic products. When unfolded, foldable display terminals offer a larger display area, enhancing the viewing experience. When folded, they achieve a smaller size, making them easy for users to carry.

[0003] The foldable display terminal includes at least: a first display panel and a folding assembly for supporting the first display panel. The first display panel may be an organic light-emitting diode (OLED) display panel.

[0004] OLED display panels typically incorporate organic materials such as CPI and PET as cover plates, serving a bending and protective function. However, the energy absorption performance of these layers is relatively poor, making them prone to developing a small, deep dent under impact from a sharp point. Summary of the Invention

[0005] This application provides a stacked structure, a display module, and an electronic device, which solves the problem of poor energy absorption performance of the stacked structure.

[0006] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0007] A first aspect of this application provides a laminated structure for a display module. The laminated structure includes: a base film, a first layer, and a second layer stacked together; the modulus of the second layer is greater than or equal to the modulus of the first layer; wherein the first layer and / or the second layer is made of an energy-absorbing and impact-resistant material, and the modulus of the energy-absorbing and impact-resistant material is greater than or equal to 0.5 GPa. Therefore, by providing a first layer and / or a second layer with energy-absorbing and impact-resistant properties inside the base film, a buffering effect can be further achieved using the first layer and / or the second layer: on the one hand, the energy-absorbing and impact-resistant material has a high modulus, effectively blocking external impact stress or compressive stress and protecting the display module from damage; on the other hand, the energy-absorbing and impact-resistant material has superior energy absorption performance, capable of absorbing impact energy or compressive energy, thus improving the buffering performance of the laminated structure. This application designs the base film, the first layer, and the second layer to have different properties. By utilizing the synergistic effect of the properties of the base film, the first layer, and the second layer, the laminated structure can have good impact resistance, energy absorption, and bending performance, thereby improving the protection capability of the display module.

[0008] In one alternative implementation, the energy-absorbing and impact-resistant material includes a glassy polyurethane GPU, which comprises multiple hydrogen bonds or dynamic bonds, including disulfide bonds and boron-oxygen bonds. Thus, the introduction of multiple hydrogen bonds and dynamic bonds into the molecular structure enhances the material's self-healing properties, enabling it to possess superior energy absorption performance.

[0009] In one optional implementation, the material composition of the glassy polyurethane GPU includes: hydroxyl-terminated polyether, isocyanate, and hydrazide. Specifically, per 100 parts by molar fraction, the material composition of the glassy polyurethane GPU comprises: 20-100 parts hydroxyl-terminated polyether, 20-90 parts diisocyanate, and 10-35 parts hydrazide. Therefore, the glassy polyurethane using this material composition exhibits superior impact resistance and energy absorption properties.

[0010] In one alternative implementation, the material of the hydroxyl-terminated polyether includes at least one of polytetrahydrofuran ether (PTMG), polypropylene glycol ether (PPG), and polyethanol ether (PEG).

[0011] In one alternative implementation, the moisture content of the hydroxyl-terminated polyether is less than 400 ppm.

[0012] In one alternative implementation, the diisocyanate material includes at least one of isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), or diphenylmethane diisocyanate (MDI).

[0013] In one alternative implementation, the material of the acylhydrazine includes at least one of succinic acid dihydrazine, adipic acid dihydrazine, and octanoic acid dihydrazine.

[0014] In one optional implementation, the base film is made of at least one of polyethylene terephthalate (PET) and colorless polyimide (CPI); the first layer is made of at least one of glassy polyurethane GPU and non-Newtonian fluid; and the second layer is made of at least one of polyethylene terephthalate (PET) and glassy polyurethane GPU.

[0015] In one optional implementation, the thickness of the base film is 30-100 μm, the thickness of the first stack is 20-75 μm, and the thickness of the second stack is 20-100 μm.

[0016] In one alternative implementation, the first layer is formed on the base film by coating.

[0017] In one alternative implementation, the first stack is connected to the second stack via a first connection layer.

[0018] In one alternative implementation, the material of the first connecting layer includes optically transparent adhesive (OCA).

[0019] A second aspect of this application provides an electronic device, including a display module and a stacked structure as described in any of the preceding claims, the stacked structure being disposed on the light-emitting side of the display module.

[0020] A third aspect of this application provides a display module, including a display panel and a cover plate, the cover plate comprising: the laminated structure described above.

[0021] A fourth aspect of this application provides a method for preparing a glassy polyurethane GPU, the method comprising: dissolving 20-100 parts of hydroxyl-terminated polyether in a solvent, adding 20-90 parts of diisocyanate IPDI and a catalyst, carrying out a catalytic reaction to obtain an isocyanate-based NCO-terminated polyether prepolymer, adding 10-35 parts of hydrazide, and reacting to generate a glassy polyurethane GPU.

[0022] In one alternative implementation, the solvent includes dimethylacetamide (DMAC).

[0023] In one alternative implementation, the catalyst comprises: dibutyltin dilaurate.

[0024] In one alternative implementation, the hydroxyl-terminated polyether comprises at least one of polytetrahydrofuran ether (PTMG), polypropylene glycol ether (PPG), and polyethanol ether (PEG).

[0025] In one alternative implementation, the diisocyanate comprises at least one of isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), or diphenylmethane diisocyanate (MDI).

[0026] In one alternative implementation, the acylhydrazine comprises at least one of succinic acid dihydrazine, adipic acid dihydrazine, and octanoic acid dihydrazine.

[0027] This application provides a laminated structure, a display module, and an electronic device. The display module includes a flexible screen and a foldable screen. In some embodiments, the laminated structure is disposed on the display module, serving as a protective film. In other embodiments, the display module includes a cover plate and a display panel, the cover plate including the laminated structure. The laminated structure includes a base film, a first layer, and a second layer stacked together; the modulus of the second layer is greater than or equal to the modulus of the first layer; wherein the first layer and / or the second layer is made of an energy-absorbing and impact-resistant material, the modulus of which is greater than or equal to 0.5 GPa. Therefore, by providing a first layer and / or a second layer with energy-absorbing and impact-resistant properties inside the base film, a buffering effect can be further achieved using the first layer and / or the second layer: on the one hand, the energy-absorbing and impact-resistant material has a high modulus, effectively blocking external impact stress or compressive stress, protecting the display module from damage; on the other hand, the energy-absorbing and impact-resistant material has superior energy absorption performance, capable of absorbing impact energy or compressive energy, thus improving the buffering performance of the laminated structure. This application designs the base film, the first layer, and the second layer to have different properties. By utilizing the synergistic effect of the properties of the base film, the first layer, and the second layer, the laminated structure can have good impact resistance, energy absorption, and bending performance, thereby improving the protection capability of the display module.

[0028] In some embodiments, the energy-absorbing and impact-resistant material comprises a glassy polyurethane GPU, which includes multiple hydrogen bonds or dynamic bonds, including disulfide bonds and boron-oxygen bonds. Thus, the introduction of multiple hydrogen bonds and dynamic bonds into the molecular structure enhances the material's self-healing properties and enables it to possess superior energy absorption performance. Attached Figure Description

[0029] Figure 1 A schematic diagram of the disassembly structure of an electronic device provided in an embodiment of this application;

[0030] Figure 2 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application;

[0031] Figure 3 A cross-sectional view of an electronic device provided in an embodiment of this application;

[0032] Figure 4 This is a schematic diagram of a layered structure.

[0033] Figure 5 This is a schematic diagram of a stacked structure provided in an embodiment of this application;

[0034] Figure 6 This is a schematic diagram of another stacked structure provided in an embodiment of this application;

[0035] Figure 7This is a schematic diagram of another stacked structure provided in an embodiment of this application;

[0036] Figure 8 This is a schematic diagram of another stacked structure provided in an embodiment of this application;

[0037] Figure 9 A schematic diagram of another layered structure provided in this application embodiment;

[0038] Figure 10 , Figure 11 , Figure 12 , Figure 13 , Figure 14 To prepare such Figure 7 A schematic diagram of the semi-finished product structure obtained from the stacked structure shown;

[0039] Figure 15 This is a flowchart illustrating a method for fabricating a glassy polyurethane GPU, as provided in an embodiment of this application. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this application clearer, the application will now be described in further detail with reference to the accompanying drawings.

[0041] In the following description, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0042] Furthermore, in this application, directional terms such as "upper" and "lower" are defined relative to the orientation of the components shown in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the orientation of the components in the accompanying drawings.

[0043] This application provides an electronic device. This electronic device can be a tablet computer, mobile phone, e-reader, remote control, personal computer (PC), laptop computer, personal digital assistant (PDA), in-vehicle device, smart TV, wearable device, television set, or other products with a display interface, as well as smart display wearable products such as smartwatches and smart bracelets. This application does not impose any special limitations on the form of the above-mentioned electronic device. For ease of explanation, the following embodiments all use a mobile phone as an example for illustration.

[0044] like Figure 1 As shown, the electronic device 1 includes a display module 10, a mid-frame 11, and a housing (or battery cover) 12. The mid-frame 11 is located between the display module 10 and the housing 12.

[0045] Display module 10 is used to display images.

[0046] The display module 10, the middle frame 11, and the housing 12 can be disposed on different layers in the thickness direction of the electronic device. These layers can be parallel to each other, and the plane in which each layer is located can be called the XY plane, and the direction perpendicular to the XY plane can be called the Z direction. That is to say, the display module 10, the middle frame 11, and the housing 12 can be distributed in layers in the Z direction.

[0047] Display module 10 can be used as follows Figure 1 The flexible printed circuit (FPC) shown passes through the middle frame 11 and is electrically connected to the PCB disposed on the middle frame 11. This allows the PCB to transmit display data to the display module 10 to control the display module 10 to display images.

[0048] The middle frame 11 is located between the display module 10 and the housing 12. The surface of the middle frame 11 away from the display module 10 is used to mount internal components such as batteries, printed circuit boards (PCBs), cameras, and antennas. After the housing 12 is closed with the middle frame 11, the aforementioned internal components are located between the housing 12 and the middle frame 11.

[0049] The housing 12 is connected to the middle frame 11 to form a cavity for accommodating the aforementioned electronic components such as the PCB, camera, and battery. This prevents external moisture and dust from entering the cavity and affecting the performance of the electronic components.

[0050] This application does not limit the structure of the mobile phone in its embodiments. In some embodiments of this application, such as... Figure 2 As shown, the mobile phone can be a candybar phone, and the display module 10 includes a display panel 102, which is non-foldable.

[0051] In other embodiments, the electronic device is a foldable screen phone.

[0052] like Figure 3 As shown, the display panel 102 can be a flexible screen.

[0053] The aforementioned middle frame 11 includes a first middle frame 201, a second middle frame 202, and a pivot 203 located between the first middle frame 201 and the second middle frame 202. The first middle frame 201 and the second middle frame 202 can rotate along the axis of the pivot 203, thereby causing the display panel 102 to fold or unfold.

[0054] For example, when the included angle α between the first middle frame 201 and the second middle frame 202 is 0°, the display panel 102 is in a folded state.

[0055] Alternatively, when the included angle α between the first middle frame 201 and the second middle frame 202 increases to 180°, the display panel 102 is in the unfolded state.

[0056] Among them, the flexible screen can be an active matrix organic light-emitting diode (AMOLED) display panel.

[0057] As a self-emissive display panel, AMOLED displays do not require a backlight module (BLM). Therefore, when the substrate of an AMOLED display panel is made of a flexible resin material, such as polyimide (PI) or polyethylene terephthalate, the AMOLED display panel can be bent.

[0058] In addition, other electronic components, such as cameras, headphones, earpieces, buttons, batteries, etc., may be provided on the first middle frame 201 and the second middle frame 202. This application embodiment does not limit the other electronic components provided on the first middle frame 201 and the second middle frame 202.

[0059] In some embodiments, to protect the display panel 102, the display module 10 further includes a cover plate 101 and a protective layer 104, the cover plate 101 and the protective layer 104 being disposed, for example, on the light-emitting side of the display panel 102. Figure 3 As shown, the display panel 102 has a cover plate 101 and a protective layer 104 on the side away from the support layer 103. The protective layer 104 adopts a stacked structure.

[0060] It should be noted that it is also possible to... Figure 2 The light-emitting surface of the display panel 102 of the candybar phone shown is provided with a cover plate 101 and a protective layer 104.

[0061] In other embodiments, the cover plate 101 may include the protective layer 104, that is, the cover plate 101 includes a laminated structure.

[0062] Figure 4 This is a schematic diagram of a layered structure. For example... Figure 4 As shown, the stacked structure 100 includes: a base film 1011 and a first stack 1013 stacked together. The base film 1011 is connected to the first stack 1013 through a first connecting layer 1012. A second connecting layer 1014 is provided on the side of the first stack 1013 away from the base film 1011. The first stack 1013 can be connected to the display panel through the second connecting layer 1014.

[0063] The base film 1011 may be made of at least one of the following: polyethylene terephthalate (PET), colorless polyimide (CPI), polymethyl methacrylate (PMMA), polycarbonate (PC), triacetyl cellulose (TAC), and polynaphthalate (PEN).

[0064] The material of the first laminate 1013 may include at least one of the following: thermoplastic polyurethanes (TPU), nylon elastomer (TPAE), optically transparent silicone (Si adhesive), acrylic adhesive, and modified polyurethane.

[0065] Thermoplastic polyurethane (TPU) is a block copolymer, a polymer composed of alternating sequences of hard and soft segments. It has wide applications in wire and cable sheathing, hoses, pipes, adhesives, and textile coatings, and can be used as an impact modifier for other polymers. It can also be used in high-performance, high-transparency films, for example, in high-impact glass structures.

[0066] Thermoplastic polyurethane can be polyester-type aliphatic TPU, polyether-type aromatic TPU, polyester-type aromatic TPU, or polyester-type aliphatic TPU.

[0067] The material of the first connecting layer 1012 may include optically clear adhesive (OCA) or pressure-sensitive adhesive. It has good adhesion and can effectively improve the strength and reliability of the connection between the base film 1011 and the first stacked layer 1013, thereby further improving the stability and reliability of the display module. The material of the second connecting layer 1014 can be referred to the description of the first connecting layer 1012, and will not be repeated here.

[0068] Pressure-sensitive adhesive (PSA) is a non-reactive adhesive, meaning that two structural components can be bonded together under appropriate pressure without the need for solvents, water, or heat to activate its adhesive properties. This effectively improves the ease of use of the first bonding layer 1012. The PSA can be a thermosetting or a photocurable type.

[0069] Meanwhile, the pressure-sensitive adhesive also has a certain degree of elasticity, which allows the first connecting layer 1012 to play a certain elastic buffering role while realizing the connection function, thereby providing further buffer protection for the display panel 102 and improving the service life of the display panel 102.

[0070] The embodiments of this application do not limit the assembly method of the first connecting layer 1012.

[0071] In some embodiments of this application, the first connecting layer 1012 may first form an adhesive layer and then be disposed on the surfaces opposite to the base film 1011 and the first stack 1013, or disposed on the surfaces opposite to the first stack 1013 and the base film 1011, and then the base film 1011 and the first stack 1013 are pressed together, and the first stack 1013 and the base film 1011 are connected by the first connecting layer 1012.

[0072] In some embodiments, the base film 1011 is made of PET, the first connecting layer 1012 is made of OCA, the first stack 1013 is made of TPU, and the second connecting layer 1014 is made of OCA.

[0073] In the above embodiment, the first layer is made of TPU. Since TPU has poor energy dissipation characteristics and weak ability to absorb impact energy, it does not provide good protection for the display panel below, making the display panel easy to be damaged.

[0074] Figure 5 This is a schematic diagram of another type of stacked structure. This stacked structure is disposed on the display module. Figure 5As shown, the stacked structure 100 may include: a base film 1011, a first stack 1013, a first connecting layer 1012, a second stack 1015, and a second connecting layer 1014 stacked together, wherein the modulus of the second stack 1015 is greater than or equal to the modulus of the first stack 1013.

[0075] The first stack 1013 is connected to the second stack 1015 via the first connecting layer 1012 and the second stack 1015. The second stack 1015 is connected to the side away from the base film 1011 by a second connecting layer 1014. The second stack 1015 can be connected to the display module via the second connecting layer 1014.

[0076] The base film 1011 may be made of at least one of the following: polyethylene terephthalate (PET), colorless polyimide (CPI), polymethyl methacrylate (PMMA), polycarbonate (PC), cellulose triacetate (TAC), and polynaphthalene ester (PEN).

[0077] The material of the first laminate 1013 may include at least one of the following: thermoplastic polyurethane elastomer rubber (TPU), nylon elastomer (TPAE), optically transparent silicone, acrylic optical adhesive, modified polyurethane, and non-Newtonian fluid.

[0078] The material of the second laminate 1015 may include at least one of the following: polyethylene terephthalate (PET), colorless polyimide (CPI), polymethyl methacrylate (PMMA), polycarbonate (PC), cellulose triacetate (TAC), and polynaphthalene ester (PEN).

[0079] In some embodiments, the base film 1011 is made of PET, the first stack 1013 is made of a non-Newtonian fluid, the first connecting layer 1012 is made of OCA, the second stack 1015 is made of PET, and the second connecting layer 1014 is made of OCA.

[0080] The first layer 1013 is made of a non-Newtonian fluid. Non-Newtonian fluids have a low modulus (approximately 100 kPa) and are easily dented by sharp impacts.

[0081] Therefore, embodiments of this application provide a laminated structure for display modules, the laminated structure including an energy-absorbing and impact-resistant material, which can take into account both energy absorption performance and impact resistance performance.

[0082] This application does not limit the position of the stacked structure in the display module. In some embodiments, the stacked structure can be disposed on the light-emitting side of the display module. When the stacked structure is disposed on the light-emitting side of the display module, it can be attached to the light-emitting surface of the display module, and the stacked structure can be disposed on the display module as a protective film.

[0083] In other embodiments, the stacked structure can be disposed within the display module. In some examples of this embodiment, the display module may include a display panel and a cover plate, the cover plate comprising the stacked structure described above.

[0084] like Figure 6 As shown, the stacked structure may include: a base film 1011, a first stack 1013, and a second stack 1015 stacked together.

[0085] The base film 1011 may be made of at least one of the following: polyethylene terephthalate (PET), colorless polyimide (CPI), polymethyl methacrylate (PMMA), polycarbonate (PC), cellulose triacetate (TAC), and polynaphthalene ester (PEN).

[0086] In some embodiments, the second stack 1015 may adopt a high-modulus stack structure, and the first stack 1013 may adopt a low-modulus stack structure, wherein the modulus of the high-modulus stack structure is greater than the modulus of the low-modulus stack structure.

[0087] In other embodiments, the modulus of the second stack 1015 is equal to the modulus of the first stack 1013.

[0088] In some embodiments of this application, the first stack and / or the second stack are made of an energy-absorbing and impact-resistant material. The modulus of the energy-absorbing and impact-resistant material is greater than or equal to 0.5 GPa, and the energy absorption performance of the material is superior. For example, the energy absorption performance of the energy-absorbing and impact-resistant material is better than that of the base film 1011. When measuring the energy absorption performance of the material, the material to be tested can be attached to the surface of a brittle object (screen), and the height to which the brittle object withstands a sharp impact is observed; the higher the impact height, the better the energy absorption.

[0089] Wherein, the first stack and / or the second stack are made of energy-absorbing and impact-resistant materials, which may be that the first stack 1013 is made of energy-absorbing and impact-resistant materials and the second stack 1015 is made of other materials with higher modulus, or the second stack 1015 is made of energy-absorbing and impact-resistant materials and the first stack 1013 is made of materials with lower modulus, or both the first stack 1013 and the second stack 1015 are made of energy-absorbing and impact-resistant materials.

[0090] This application does not limit the type of energy-absorbing and impact-resistant material. In some embodiments, the energy-absorbing and impact-resistant material includes: glassy polyurethane (GPU) material, which has a modulus of up to GPa and also has good energy absorption performance, and can effectively improve the energy absorption performance of the laminate.

[0091] Among them, glassy polyurethane is a colorless and transparent glassy polyurethane with a Young's modulus greater than or equal to 0.5 GPa at room temperature. Glassy polyurethane contains multiple hydrogen bonds or other dynamic bonds, which can effectively absorb impact energy. Multiple hydrogen bonds refer to molecules containing three or more hydrogen bonds. These dynamic bonds include disulfide bonds and boron-oxygen bonds.

[0092] For example, the molecular formula of glassy polyurethane is as follows:

[0093]

[0094] Among them, the glassy polyurethane molecular chains move more freely and have better energy absorption properties.

[0095] In some embodiments, the material composition of the glassy polyurethane GPU includes: hydroxyl-terminated polyether, isocyanate, and hydrazide. Specifically, per 100 parts by molar fraction, the material composition of the glassy polyurethane GPU includes: 20-100 parts hydroxyl-terminated polyether, 20-90 parts diisocyanate, and 10-35 parts hydrazide. The moisture content of the hydroxyl-terminated polyether is less than 400 ppm.

[0096] The hydroxyl-terminated polyether includes at least one of polytetrahydrofuran ether (PTMG), polypropylene glycol ether (PPG), and polyethanol ether (PEG).

[0097] The diisocyanate includes at least one of isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), or diphenylmethane diisocyanate (MDI).

[0098] The acylhydrazide includes at least one of succinic dihydrazide, adipate dihydrazide, and octanoic dihydrazide.

[0099] The glassy polyurethane GPU can be used to form the first stack 1013 and / or the second stack 1015.

[0100] In some embodiments of this application, the material of the first stack 1013 may include at least one of: non-Newtonian fluid, glassy polyurethane GPU. The material of the second stack 1015 may include at least one of: polyethylene terephthalate (PET), colorless polyimide (CPI), polymethyl methacrylate (PMMA), polycarbonate (PC), cellulose triacetate (TAC), polynatrimethylene ester (PEN), and glassy polyurethane GPU.

[0101] The embodiments of this application adjust the molecular structure of the first stack and / or the second stack at the microscopic level, and introduce multiple hydrogen bonds or other dynamic bonds into the molecular structure, which can make the material have better energy absorption performance and optimize the performance of the first stack 1013 and / or the second stack 1015.

[0102] This application embodiment designs the base film, the first stack, and the second stack to have different characteristics. By utilizing the synergistic properties of the base film, the first stack, and the second stack, the stack structure can possess good impact resistance, energy absorption, and bending performance, thereby improving the protection capability of the display module.

[0103] Among them, the base film has a high elastic modulus and a correspondingly high hardness. By placing it on the outside of the display module, when the display module is subjected to external impact or compression, the impact stress or compression stress will act on the base film first. At this time, the base film with high hardness can not only improve the scratch resistance and prevent the screen of the display module from being scratched, but also effectively reduce the deformation under impact stress or compression stress, thereby effectively reducing the strain of the film layers inside the display module, such as the inorganic layer.

[0104] Furthermore, a first layer and / or a second layer with energy-absorbing and impact-resistant properties are provided on the inner side of the base film. The first layer and / or the second layer can be used to further achieve a buffering effect: on the one hand, the energy-absorbing and impact-resistant material has a high modulus, which effectively blocks external impact stress or extrusion stress and protects the display module from damage; on the other hand, the energy-absorbing and impact-resistant material has excellent energy absorption performance and can absorb impact energy or extrusion energy.

[0105] When the display module is subjected to impact or compression, the stress acting on each film layer mainly manifests as lateral shear force and longitudinal compressive force. When stress acts on the base film 1011, the shear force will spread laterally to the surroundings as the base film 1011 vibrates, while the compressive force will continue to spread longitudinally to the first stack 1013 and the second stack 1015. The first stack 1013 and the second stack 1015 absorb this compressive force to a certain extent. In order to ensure that the base film 1011, the first stack 1013, and the second stack 1015 have sufficient thickness to optimize their vibration energy dissipation or energy absorption effect and reduce the impact of stress on other film layers, the thickness of the base film is 30-100um, the thickness of the first stack is 20-75um, and the thickness of the second stack is 20-100um in the direction perpendicular to the plane where the display module is located.

[0106] In some embodiments, the thickness of the base film 1011 is greater than the thickness of the first stack 1013 in a direction perpendicular to the plane of the display module. For example, the thickness of the base film 1011 is 50 μm, and the thickness of the first stack 1013 is 40 μm. By making the base film 1011 thicker, not only can the scratch resistance be improved, preventing the screen of the display module from being scratched, but the deformation under impact stress or compressive stress can also be effectively reduced, thereby effectively reducing the strain of the film layers inside the display module, such as the inorganic layer, and further improving the energy absorption and impact resistance of the first stack 1013.

[0107] By further adding a high-modulus second layer 1015 to the first layer 1013, the second layer 1015 has a correspondingly higher hardness, which can block the large deformation generated by the first layer 1013 and prevent the deformation from continuing to accumulate inward, so that the laminated structure has better impact resistance.

[0108] To optimize the impact resistance of the second stack 1015, in the direction perpendicular to the plane of the display module, the thickness of the second stack 1015 can be the same material and thickness as the base film 1011, or it can be made of different materials and have different thicknesses. For example, the base film 1011 is formed of PI material with a thickness of 50 μm, the first stack 1013 is formed of glassy polyurethane GPU with a thickness of 100 μm, and the second stack 1015 is formed of PET material with a thickness of 50 μm.

[0109] The following combination Figures 7-9 Examples of the materials and thicknesses of this laminated structure are provided. In some embodiments, such as... Figure 7 As shown, the base film 1011 is made of PET, the first layer 1013 is made of GPU, the first connecting layer 1012 is made of OCA, the second layer 1015 is made of PET, and the second connecting layer 1014 is made of OCA. The thickness of the base film is 30-100µm, the thickness of the first layer is 20-75µm, and the thickness of the second layer is 20-100µm.

[0110] In this embodiment, only the first layer 1013 uses an energy-absorbing and impact-resistant material, and this layered structure can be applied to scenarios where the impact head of a pointed impact is relatively small.

[0111] In some embodiments, such as Figure 8 As shown, the base film 1011 is made of PET, the first layer 1013 is made of a non-Newtonian fluid, the first connecting layer 1012 is made of OCA, the second layer 1015 is made of GPU, and the second connecting layer 1014 is made of OCA. The thickness of the base film is 30-100µm, the thickness of the first layer is 20-75µm, and the thickness of the second layer is 20-100µm.

[0112] In this embodiment, only the second layer 1015 uses an energy-absorbing and impact-resistant material. This stacked structure can be applied to scenarios where the impact head of a pointed impact is relatively large and it is necessary to simultaneously utilize the energy absorption function of non-Newtonian fluid and GPU.

[0113] In some embodiments, such as Figure 9 As shown, the base film 1011 is made of PET, the first layer 1013 is made of GPU, the first connecting layer 1012 is made of OCA, the second layer 1015 is made of GPU, and the second connecting layer 1014 is made of OCA. The thickness of the base film is 30-100um, the thickness of the first layer is 20-75um, and the thickness of the second layer is 20-100um.

[0114] In this embodiment, both the first layer 1013 and the second layer 1015 are made of energy-absorbing and impact-resistant materials. This stacked structure can be applied to scenarios with a large folding radius and relatively low requirements for rebound force.

[0115] The embodiments of this application do not limit the connection method between the first laminate 1013 and the base film 1011. In some embodiments, the first laminate 1013 is coated on the surface of the base film 1011.

[0116] Therefore, by coating the first layer 1013 onto the surface of the base film 1011, the adhesion between the first layer 1013 and the base film 1011 is improved. When the display module is bent or subjected to external force, the risk of the first layer 1013 detaching from the base film 1011 is reduced, thereby improving the reliability of the connection between the first layer 1013 and the base film 1011.

[0117] This application does not limit the connection method between the first stack 1013, the second stack 1015, and the display module. In some embodiments, the first stack 1013 is connected to the second stack 1015 via a first connecting layer 1012. A second connecting layer 1014 is provided on the side of the second stack 1015 away from the base film 1011, and the second stack 1015 can be connected to the display module via the second connecting layer 1014.

[0118] This application embodiment does not limit the materials of the first connecting layer 1012 and the second connecting layer 1014. In some embodiments, the materials of the first connecting layer 1012 and the second connecting layer 1014 may be OCA.

[0119] This application also provides a method for preparing a laminated structure, the method comprising:

[0120] In some examples of this embodiment, in the preparation of such Figure 7 When the stacked structure is shown, such as Figure 10As shown, a first laminate 1013 can be formed on the surface of the base film 1011 to obtain... Figure 10 The stacked structure shown includes: a base film 1011, a first stack 1013, and a first release film 10130.

[0121] The first laminate 1013 is formed on the surface of the base film 1011. This can be achieved by coating the first laminate 1013 onto the surface of the base film 1011 and then curing it, or by coating the first laminate 1013 onto the surface of a substrate and curing it on the substrate before bonding the first laminate 1013 to the base film 1011. The curing process of the first laminate 1013 includes heat curing and moisture curing. The substrate can be a release film.

[0122] Therefore, by coating the first layer 1013 onto the surface of the base film 1011, the adhesion between the first layer 1013 and the base film 1011 is improved. When the display module is bent or subjected to external force, the risk of the first layer 1013 detaching from the base film 1011 is reduced, thereby improving the reliability of the connection between the first layer 1013 and the base film 1011.

[0123] like Figure 11 As shown, a first connecting layer 1012 can be provided on the first surface of the second stack 1015, and as... Figure 12 As shown, a second connecting layer 1014 is provided on the second surface of the second stack 1015, resulting in the following: Figure 13 The layered structure shown.

[0124] The first connecting layer 1012 has a second release film 10121 and a third release film 10122 on both sides. When the first connecting layer 1012 is provided on the first surface of the second stack 1015, the third release film 10122 can be removed so that the first surface of the second stack 1015 and the first connecting layer 1012 are attached.

[0125] The second connecting layer 1014 has a fourth release film 10141 and a fifth release film 10142 on both sides. When the second connecting layer 1014 is provided on the second surface of the second stack 1015, the fifth release film 10142 can be removed so that the second surface of the second stack 1015 and the second connecting layer 1014 are attached.

[0126] Can be like Figure 13 The stacked structure shown and as Figure 10 The stacked structures shown are bonded together. See example. Figure 14 The first stack 1013 and the first connecting layer 1012 can be bonded together to obtain, as shown below. Figure 7 The layered structure shown.

[0127] In this process, the first release film 10130 on the surface of the first stack 1013 and the second release film 10121 on the surface of the first connecting layer 1012 can be removed first, and then the first stack 1013 and the first connecting layer 1012 can be bonded together.

[0128] In some embodiments, the laminated structure can be connected to the display module via the second connecting layer 1014. Before connecting the second connecting layer 1014 and the display module, the fourth release film 10141 on the surface of the second connecting layer 1014 can be removed, and then the second connecting layer 1014 and the light-emitting surface of the display module can be bonded together. This laminated structure can be used as a protective film on the display module.

[0129] In some embodiments, the above-described stacked structure may be disposed in the display module. In some examples of this embodiment, the display module may include a display panel and a cover plate, the cover plate including, for example, the stacked structure described above.

[0130] The display module provided in this application includes the stacked structure described above, which has better energy absorption performance, can better protect the display panel, and improve the protection capability of the display panel.

[0131] This application also provides a method for preparing glassy polyurethane. Taking the preparation of a glassy polyurethane GPU with a molar fraction of 100 parts as an example, as follows... Figure 15 As shown, the method includes the following steps:

[0132] S1. Dissolve 20-100 parts of hydroxyl-terminated polyether in a solvent.

[0133] The hydroxyl-terminated polyether can be dissolved in a solvent in an inert environment. For example, the reaction flask is purged with an inert gas, dried, and then dissolved in a solvent under an inert gas atmosphere. In some embodiments, the inert gas includes nitrogen.

[0134] This application does not limit the material of the solvent in the embodiments. For example, the solvent material includes dimethylacetamide (DMAC). The amount of the solvent is, for example, 300-1000 parts.

[0135] The hydroxyl-terminated polyether is made of at least one of the following: polytetrahydrofuran ether (PTMG), polypropylene glycol ether (PPG), and polyethanol ether (PEG). The moisture content of this hydroxyl-terminated polyether is less than 400 ppm.

[0136] S2. Add 20-90 parts of diisocyanate IPDI and 0.2-1.5 parts of catalyst to carry out catalytic reaction to obtain isocyanate-based NCO-terminated polyether prepolymer.

[0137] The diisocyanate includes at least one of isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), or diphenylmethane diisocyanate (MDI).

[0138] The catalyst includes: dibutyltin dilaurate.

[0139] S3. Add 10-35 parts of hydrazide and react with isocyanate-based NCO-terminated polyether prepolymer to generate glassy polyurethane GPU.

[0140] The materials of the acylhydrazine include at least one of succinic acid dihydrazine, adipic acid dihydrazine, and octanoic acid dihydrazine.

[0141] Using the above process, the glassy polyurethane can be obtained. This glassy polyurethane can be used as a material for either the first or second layer.

[0142] This application provides a laminated structure, a display module, and an electronic device. The display module includes a flexible screen and a foldable screen. In some embodiments, the laminated structure is disposed on the display module, serving as a protective film. In other embodiments, the display module includes a cover plate and a display panel, the cover plate including the laminated structure. The laminated structure includes a base film, a first layer, and a second layer stacked together; the modulus of the second layer is greater than or equal to the modulus of the first layer; wherein the first layer and / or the second layer is made of an energy-absorbing and impact-resistant material, the modulus of which is greater than or equal to 0.5 GPa. Therefore, by providing a first layer and / or a second layer with energy-absorbing and impact-resistant properties inside the base film, a buffering effect can be further achieved using the first layer and / or the second layer: on the one hand, the energy-absorbing and impact-resistant material has a high modulus, effectively blocking external impact stress or compressive stress, protecting the display module from damage; on the other hand, the energy-absorbing and impact-resistant material has superior energy absorption performance, capable of absorbing impact energy or compressive energy, thus improving the buffering performance of the laminated structure. This application designs the base film, the first layer, and the second layer to have different properties. By utilizing the synergistic effect of the properties of the base film, the first layer, and the second layer, the laminated structure can have good impact resistance, energy absorption, and bending performance, thereby improving the protection capability of the display module.

[0143] In some embodiments, the energy-absorbing and impact-resistant material comprises a glassy polyurethane GPU, which includes multiple hydrogen bonds or dynamic bonds, including disulfide bonds and boron-oxygen bonds. Thus, the introduction of multiple hydrogen bonds and dynamic bonds into the molecular structure enhances the material's self-healing properties and enables it to possess superior energy absorption performance.

[0144] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A layered structure, characterized in that, The stacked structure is disposed on the display module, and the stacked structure includes: a base film, a first stacked layer, and a second stacked layer. The modulus of the second stack is greater than or equal to the modulus of the first stack; Wherein, the first stack and / or the second stack are made of an energy-absorbing and impact-resistant material, wherein the modulus of the energy-absorbing and impact-resistant material is greater than or equal to 0.5 GPa.

2. The stacked structure according to claim 1, characterized in that, in, The energy-absorbing and impact-resistant material includes: glassy polyurethane, which includes: multiple hydrogen bonds or dynamic bonds, and the dynamic bonds include: disulfide bonds and boron-oxygen bonds.

3. The stacked structure according to claim 2, characterized in that, The glassy polyurethane material composition, by molar parts, includes: 20-100 parts of hydroxyl-terminated polyether, 20-90 parts of diisocyanate, and 10-35 parts of hydrazide.

4. The stacked structure according to claim 3, characterized in that, The moisture content of the hydroxyl-terminated polyether is less than 400 ppm.

5. The stacked structure according to claim 3 or 4, characterized in that, include: The hydroxyl-terminated polyether includes at least one of polytetrahydrofuran ether, polypropylene glycol ether, and polyethanol ether.

6. The laminated structure according to any one of claims 3-5, characterized in that, The diisocyanate includes at least one of isophorone diisocyanate, hexamethylene diisocyanate, or diphenylmethane diisocyanate.

7. The laminated structure according to any one of claims 3-6, characterized in that, The acylhydrazide includes at least one of succinic acid dihydrazide, adipic acid dihydrazide, and octanoic acid dihydrazide.

8. The laminated structure according to any one of claims 1-7, characterized in that, The base film is made of at least one of polyethylene terephthalate and colorless polyimide; the first laminate is made of at least one of glassy polyurethane and non-Newtonian fluid; and the second laminate is made of at least one of polyethylene terephthalate and glassy polyurethane.

9. The laminated structure according to any one of claims 1-8, characterized in that, The thickness of the base film is 30-100 μm, the thickness of the first stack is 20-75 μm, and the thickness of the second stack is 20-100 μm.

10. The laminated structure according to any one of claims 1-9, characterized in that, The first layer is formed on the base film by coating.

11. The laminated structure according to any one of claims 1-10, characterized in that, The first stack is connected to the second stack via a connecting layer.

12. The stacked structure according to claim 11, characterized in that, The material of the connecting layer includes: optically transparent adhesive.

13. An electronic device, characterized in that, It includes a display module and a stacked structure as described in any one of claims 1-12, wherein the stacked structure is disposed on the light-emitting side of the display module.

14. A display module, characterized in that, include: Display panel and cover plate, the cover plate comprising: a stacked structure as described in any one of claims 1-12.

15. An electronic device, characterized in that, It includes a housing and a display module as described in claim 14, the display module being disposed within the housing.

16. A method for preparing glassy polyurethane, characterized in that, The method includes: Dissolve 20-100 parts of hydroxyl-terminated polyether in a solvent; Add 20-90 parts of diisocyanate and 0.2-1.5 parts of catalyst to carry out a catalytic reaction to obtain isocyanate-terminated polyether prepolymer; Add 10-35 parts of hydrazide to react with isocyanate-terminated polyether prepolymer to generate glassy polyurethane.

17. The method for preparing glassy polyurethane according to claim 16, characterized in that, The glassy polyurethane comprises multiple hydrogen bonds or dynamic bonds, wherein the dynamic bonds include disulfide bonds and boron-oxygen bonds.

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