Folding screen device and electronic equipment

Abstract

The invention discloses a folding screen device and electronic equipment, and relates to the technical field of folding screens. The folding screen device comprises a flexible cover plate, a first adhesive layer, a display layer, a second adhesive layer and a supporting layer which are sequentially stacked, wherein a plurality of first microsphere particles are arranged in the first adhesive layer, and the plurality of first microsphere particles are distributed in the first adhesive layer in a single-layer manner; the first microsphere particle comprises a first core and a first shell, and under the condition that the first microsphere particle is subjected to external force, the elastic deformation quantity of the first shell is greater than that of the first core.

Description

Technical Field

[0001] This application relates to the technical field of folding screens, and particularly to a folding screen device and an electronic device. Background Art

[0002] In related technologies, a folding screen generally includes a flexible cover plate, an upper layer of Optical Clear Adhesive (OCA) glue layer, a polarizer, a display layer, a lower layer of OCA glue layer, and a support backplane from top to bottom. Among them, the flexible cover plate, the display layer, and the support backplane are relatively hard materials. Therefore, when bending, the interlayer stress is large, and soft and substrate-free OCA is required for bonding to buffer the interlayer stress and reduce damage to the display layer.

[0003] Among them, relative displacements will occur in each hard layer of the folding screen when bending. Especially, the stress concentration is the largest in the bending center area. At this time, the OCA glue layer generates elastic deformation under the action of tensile / compressive stress. After repeated bending / unfolding many times, the OCA glue in the middle of the screen begins to creep and thin, and the degree of recovery after elastic deformation becomes worse, gradually undergoing irreversible creep, resulting in deep creases on the screen. It can be seen that in related technologies, there is a problem that creases are easily generated at the folding positions of folding screens. Summary of the Invention

[0004] This application provides a folding screen device and an electronic device, which can slow down the generation of creases in the folding screen device.

[0005] In a first aspect, this application provides a folding screen device, including: a flexible cover plate, a first glue layer, a display layer, a second glue layer, and a support layer that are sequentially stacked;

[0006] Among them, a plurality of first microsphere particles are provided in the first glue layer, and the plurality of first microsphere particles are distributed in a single layer in the first glue layer;

[0007] The first microsphere particle includes a first core and a first outer shell. When the first microsphere particle is subjected to an external force, the elastic deformation amount of the first outer shell is greater than the elastic deformation amount of the first core.

[0008] In a second aspect, this application provides an electronic device, including the folding screen device described in the first aspect.

[0009] In the embodiments of the present application, by providing a plurality of first microsphere particles in the first adhesive layer, during the folding process of the folding screen device, since when the first microsphere particles are subjected to an external force, the elastic deformation amount of the first outer shell is greater than that of the first core, that is, the first core is not easily deformed, a thickness support effect can be formed, so that the first adhesive layer is not easily thinned due to fatigue; at the same time, since when the first microsphere particles are subjected to an external force, the elastic deformation amount of the first outer shell is relatively large, that is, the first outer shell is relatively easily elastically deformed. In this way, when the folding screen device is unfolded, since the first outer shell has a certain resilience, it can assist the adhesive layer to elastically deform, thereby effectively reducing the generation of creases. At the same time, the microsphere structure can improve the overall rigidity of the screen, ensuring that the core display layer will not be directly hit during the ball-drop and pen-drop tests, thus greatly enhancing the screen reliability. In addition, since the first adhesive layer is located on the display side of the folding screen device, by arranging the plurality of first microsphere particles in a single layer in the first adhesive layer, in this way, it can be ensured that the number of layers of the first microsphere particles in the first adhesive layer is only one layer, avoiding the problem that the overall display effect of the folding screen device is significantly reduced due to the presence of more than two layers of first microsphere particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a cross-sectional view of the folding screen device provided by the embodiments of the present application;

[0011] Figure 2 is Figure 1 a partial schematic diagram in

[0012] Figure 3 is a comparison schematic diagram of the adhesive layer with microsphere particles and the adhesive layer without microsphere particles in the folded state;

[0013] Figure 4 is a comparison schematic diagram of the folding screen device with microsphere particles and the folding screen device without microsphere particles during the ball-drop and pen-drop tests;

[0014] Figure 5 is an internal structure schematic diagram of the first adhesive layer in the embodiments of the present application;

[0015] Figure 6 is a comparison schematic diagram of the light propagation process when multiple layers of microsphere particles and a single layer of microsphere particles are added to the adhesive layer;

[0016] Figure 7 is an internal structure schematic diagram of the second adhesive layer in the embodiments of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] Next, the technical solutions in the embodiments of the present application will be clearly described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.

[0018] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are usually of the same type, and the number of objects is not limited. For example, the first object can be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the related objects before and after are in an "or" relationship.

[0019] Next, in conjunction with the accompanying drawings, a folding screen device and an electronic device provided in the embodiments of the present application will be described in detail through specific embodiments and their application scenarios.

[0020] Please refer to Figure 1 and Figure 2 , the embodiments of the present application provide a folding screen device, and the folding screen device includes: a flexible cover plate 100, a first adhesive layer 200, a display layer 300, a second adhesive layer 400, and a support layer 500 that are sequentially stacked;

[0021] Among them, a plurality of first microsphere particles 600 are provided in the first adhesive layer 200, and the plurality of first microsphere particles 600 are distributed in a single layer in the first adhesive layer 200.

[0022] It can be understood that the above folding screen device can be used as a screen module of various folding screen devices;

[0023] The first microsphere particle 600 includes a first core 610 and a first outer shell 620. When the first microsphere particle 600 is subjected to an external force, the elastic deformation amount of the first outer shell 620 is greater than the elastic deformation amount of the first core 610.

[0024] The above first microsphere particle 600 can be a core-shell structure. Among them, the core-shell structure means that: a core is composed of particles of micron or nanometer size, and then one or more layers of uniform heterogeneous or homogeneous materials are coated on the core to form an outer shell, and the core and the outer shell are connected by electrostatic action or chemical bond action. In the embodiments of the present application, the first microsphere particle 600 can be a core-shell structure formed by connecting a heterogeneous outer shell to a micron-sized particle through chemical bond action.

[0025] Among them, the above-mentioned first adhesive layer 200 and second adhesive layer 400 can both be OCA adhesive layers.

[0026] The fact that the above-mentioned multiple first microsphere particles 600 are distributed in a single layer in the first adhesive layer 200 may mean that: along the thickness direction of the first adhesive layer 200, the number of layers of the first microsphere particles 600 is only one layer, that is, there are no stacked first microsphere particles 600 in the thickness direction of the first adhesive layer 200. Among them, among the multiple first microsphere particles 600, the distances between different first microsphere particles 600 and the flexible cover plate 100 layer can be the same or different. For example, please refer to Figure 2 , the multiple first microsphere particles 600 can be relatively evenly distributed in different regions of the first adhesive layer 200.

[0027] It can be understood that the above-mentioned flexible cover plate 100, display layer 300, and support layer 500 can be the flexible cover plate 100, display layer 300, and support layer 500 in various types of display screens in the related art.

[0028] The above-mentioned first core 610 and the first outer shell 620 are connected by chemical bonds.

[0029] Among them, the external forces received by the above-mentioned first microsphere particles 600 can include: external forces in various scenarios where the electronic device may be subjected to external forces during production and normal use. For example, the external force can be the extrusion force of the first adhesive layer 200 received by the electronic device during the folding process. Or, the external force can also be the impact force received during the ball-drop and pen-drop tests, etc.

[0030] In some embodiments of the present application, the above-mentioned first outer shell 620 can be made of an elastic material, and the above-mentioned first core 610 can be made of a hard material that is not easily deformed. In this way, when the first microsphere particles 600 are subjected to external forces, the first outer shell 620 can undergo elastic deformation, while the first core 610 hardly undergoes deformation. For example, in some embodiments of the present application, the material of the first outer shell 620 can be polymethyl methacrylate (PMMA), and the material of the first core 610 can be selected from hard silica, polystyrene (PS), or hard PMMA, etc.

[0031] In this embodiment, by providing a plurality of first microsphere particles 600 in the first adhesive layer 200, during the folding process of the folding screen device, since when the first microsphere particles 600 are subjected to an external force, the elastic deformation amount of the first outer shell 620 is greater than that of the first core 610, that is, the first core 610 is not easily deformed, a thickness support effect can be formed, so that the first adhesive layer 200 is not easily thinned due to fatigue. For example, please refer to Figure 3 (a), which is a schematic diagram of the adhesive layer in a folded state when microsphere particles are added to the adhesive layer. Please refer to Figure 3 (b), which is a schematic diagram of the adhesive layer in a folded state when no microsphere particles are added to the adhesive layer. From Figure 3 (a) and Figure 3 (b), it can be seen that the thickness of the adhesive layer with added microsphere particles at the folding position in the folded state is greater than that of the adhesive layer without added microsphere particles at the folding position in the folded state. Note that since when the first microsphere particles 600 are subjected to an external force, the elastic deformation amount of the first outer shell 620 is relatively large, that is, the first outer shell 620 is relatively easily elastically deformed. In this way, when the folding screen device is unfolded, since the first outer shell 620 has a certain resilience, it can assist the adhesive layer to elastically deform, thereby effectively reducing the generation of creases. At the same time, the microsphere structure can improve the overall rigidity of the screen. Please refer to Figure 4 (b), which can ensure that the core display layer 300 is not directly hit during the ball-drop and pen-drop tests, thus greatly enhancing the screen reliability. Correspondingly, please refer to Figure 4 (a), when no microsphere particles are added to the adhesive layer, the core display layer 300 is easily directly hit during the ball-drop and pen-drop tests. In addition, since the first adhesive layer 200 is located on the display side of the folding screen device, by ensuring that there are no stacked first microsphere particles 600 in the thickness direction of the first adhesive layer 200, in this way, it can be ensured that the number of layers of the first microsphere particles 600 in the first adhesive layer 200 is only one layer, avoiding the problem that the overall display effect of the folding screen device is greatly reduced due to the existence of more than two layers of the first microsphere particles 600.

[0032] Optionally, the first microsphere particles 600 are connected to the first adhesive layer 200 by chemical bonds.

[0033] In this embodiment, when the microsphere particles are separated from the OCA adhesive layer, voids will be generated, which will change the refractive index and scattering of light, etc., and further affect the display effect of the folding screen. Based on this, in the embodiments of the present application, by connecting the first microsphere particles 600 to the first adhesive layer 200 through chemical bonds, in this way, effective strong adhesion can be formed between the microsphere particles and the adhesive layer, so that the microsphere particles and the adhesive layer are integrated. In this way, during the folding process of the folding screen device, the microsphere particles will not be separated from the adhesive layer due to weak adhesion, thereby improving the display life of the folding screen device.

[0034] Optionally, the polarity of the material on the surface of the first microsphere particles 600 is the same as the polarity of the material of the first adhesive layer 200; and / or,

[0035] The surface of the first microsphere particles 600 has a first chemical functional group 630 formed by chemical grafting treatment, and the first chemical functional group 630 is connected to the first adhesive layer 200 through a chemical bond.

[0036] Among them, the types of the polarity of the above materials may include: polar, non-polar, and weakly polar, etc. Correspondingly, the fact that the polarity of the material on the surface of the first microsphere particles 600 is the same as the polarity of the material of the first adhesive layer 200 means that the type of the polarity of the material on the surface of the first microsphere particles 600 is the same as the type of the polarity of the material of the first adhesive layer 200. For example, the polarity type of the material on the surface of the first microsphere particles 600 and the polarity type of the material of the first adhesive layer 200 are both polar. Or, the polarity type of the material on the surface of the first microsphere particles 600 and the polarity type of the material of the first adhesive layer 200 are both non-polar, etc.

[0037] Specifically, the material on the surface of the first microsphere particles 600 may specifically refer to the material of the outer shell of the first microsphere particles 600. The outer shell of the first microsphere particles 600 and the first adhesive layer 200 can adopt various materials with the same polarity. Among them, the materials of the outer shell of the first microsphere particles 600 and the first adhesive layer 200 may be the same or different, and only need to ensure that their polarities are the same. For example, in some embodiments of the present application, the materials of the outer shell of the first microsphere particles 600 and the first adhesive layer 200 may be acrylic resins of the same material.

[0038] Specifically, according to the principle of like dissolves like, the first microsphere particles 600 with the same polarity are filled into the first adhesive layer 200. An effective strong bond is formed between the surface of the first microsphere particles 600 and the first adhesive layer 200, so that the first microsphere particles 600 and the first adhesive layer 200 are fused into one. Among them, the main principle of like dissolves like is the wetting of substances with the same polarity, rather than the traditional dissolution. That is, the outer shell of the first microsphere particles 600 will not dissolve into the first adhesive layer 200, that is, the outer shell of the first microsphere particles 600 in the first adhesive layer 200 will not dissipate. Among them, the strong bond means that a chemical bond is formed between the outer shell of the first microsphere particles 600 and the first adhesive layer 200. In this way, the first microsphere particles 600 can be connected to the first adhesive layer 200 through chemical bonds.

[0039] In some other embodiments of the present application, the polarity of the material on the surface of the first microsphere particles 600 is different from the polarity of the material of the first adhesive layer 200, and the surface of the first microsphere particles 600 has a first chemical functional group 630 formed by chemical grafting treatment, and the first chemical functional group 630 is connected to the first adhesive layer 200 through a chemical bond.

[0040] In some other embodiments of the present application, the polarity of the material on the surface of the first microsphere particles 600 is the same as the polarity of the material of the first adhesive layer 200, and the surface of the first microsphere particles 600 has a first chemical functional group 630 formed by chemical grafting treatment, and the first chemical functional group 630 is connected to the first adhesive layer 200 through a chemical bond.

[0041] It should be noted that when the polarity of the material on the surface of the first microsphere particles 600 is different from the polarity of the material of the first adhesive layer 200, the polarity of the material on the surface of the first microsphere particles 600 can be made close to the polarity of the material of the first adhesive layer 200. Since two materials with similar polarities may also form chemical bonds, this is beneficial to improving the strong bonding effect between the first microsphere particles 600 and the first adhesive layer 200. Among them, the similar polarity may mean that among the polarity of the material on the surface of the first microsphere particles 600 and the polarity of the material of the first adhesive layer 200, one is polar and the other is weakly polar.

[0042] In some embodiments of the present application, the material of the first adhesive layer 200 can be acrylic resin to improve the comprehensive light performance of the first adhesive layer 200. The material of the outer shell of the first microsphere particles 600 can be polymethyl methacrylate (PMMA), and the material of the core of the first microsphere particles 600 can be selected from hard silica, polystyrene (PS), or hard PMMA, etc.

[0043] The above-mentioned first chemical functional group 630 can be various types of functional groups capable of forming chemical bonds with the first adhesive layer 200. For example, the first chemical functional group 630 can be chemical functional groups such as tetrabutyl titanate and siloxane. Specifically, a chemical grafting treatment can be performed on the surface of the first microsphere particles 600, so that the first microsphere particles 600 can be connected to the first adhesive layer 200 through chemical bonds. Please refer to Figure 5 , which is a schematic diagram of the strong adhesion of the first microsphere particles 600 to the first adhesive layer 200 through the first chemical functional group 630 on the surface.

[0044] In this embodiment, by making the polarity of the material on the surface of the first microsphere particles 600 the same as the polarity of the material of the first adhesive layer 200; and / or, the surface of the first microsphere particles 600 has a first chemical functional group 630 formed by chemical grafting treatment, and the first chemical functional group 630 is connected to the first adhesive layer 200 through chemical bonds. In this way, the first microsphere particles 600 can be connected to the first adhesive layer 200 through chemical bonds.

[0045] Optionally, the first microsphere particles 600 include a first core 610 and a first outer shell 620. The first core 610 is connected to the first outer shell 620 through chemical bonds, and the value range of the elastic modulus of the first outer shell 620 is: 1 to 1.1 times the elastic modulus of the first adhesive layer 200.

[0046] It can be understood that the connection of the above-mentioned first microsphere particles 600 to the first adhesive layer 200 through chemical bonds can mean that the first outer shell 620 of the first microsphere particles 600 is connected to the first adhesive layer 200 through chemical bonds.

[0047] The above-mentioned elastic modulus is a physical quantity that describes the ability of a material to resist deformation in the elastic deformation stage, and is usually defined as the ratio of stress to strain.

[0048] In some embodiments of the present application, the elastic modulus of the first outer shell 620 can be adjusted to 1 to 1.1 times the elastic modulus of the first adhesive layer 200 by debugging the formula of the first outer shell 620.

[0049] In this embodiment, by making the value range of the elastic modulus of the first outer shell 620 be: 1 to 1.1 times the elastic modulus of the first adhesive layer 200. In this way, during the folding process of the folding screen device, the first microsphere particles 600 can generate reversible elastic deformation, thereby absorbing the bending stress, and further avoiding the creep accumulation of the first adhesive layer 200 to slow down the generation of creases.

[0050] Optionally, in the first adhesive layer 200, the distance between two adjacent first microsphere particles 600 ranges from 50 μm to 100 μm.

[0051] Specifically, the fact that the distance between two adjacent first microsphere particles 600 ranges from 50 μm to 100 μm specifically means that: the density of the first microsphere particles 600 in the first adhesive layer 200 is 1 - 2 first microsphere particles 600 per 100-μm length section.

[0052] In this embodiment, by making the distance between two adjacent first microsphere particles 600 in the first adhesive layer 200 range from 50 μm to 100 μm, in this way, a certain interval distance can exist between the first microsphere particles 600 in the first adhesive layer 200, avoiding the over-concentration of the first microsphere particles 600 and affecting the display effect of the folding screen device.

[0053] Optionally, the first microsphere particle 600 includes a first core 610 and a first shell 620, the first core 610 and the first shell 620 are connected by chemical bonds, and the refractive index of the first core 610, the refractive index of the first shell 620, and the refractive index of the first adhesive layer 200 are equal.

[0054] Among them, the refractive index of the first shell 620 can be regulated by selecting acrylic resins with different formulations. The refractive index of the first core 610 can be regulated by the grain size and surface morphology. For example, when the first core 610 is made of SiO2, the refractive index of the first core 610 can be regulated by the grain size and surface morphology. When the first core 610 is made of PS, the refractive index of the first core 610 can be regulated by the molecular chain length and degree of polymerization. It should be noted that in the related art, microsphere particles with different refractive indices can be directly purchased.

[0055] Please refer to Figure 6 (b). When the refractive index of the first core 610, the refractive index of the first shell 620, and the refractive index of the first adhesive layer 200 are equal, the optical path in the first adhesive layer 200 can be controlled. Please refer to Figure 6 (a). When the number of layers of microsphere particles in the first adhesive layer 200 is not limited and the refractive indices of the microsphere particles and the first adhesive layer 200 are not limited either, the optical path in the first adhesive layer 200 will be uncontrollable.

[0056] In this embodiment, by making the refractive index of the first core 610, the refractive index of the first shell 620, and the refractive index of the first adhesive layer 200 equal, in this way, the optical path in the first adhesive layer 200 can be controlled, which is beneficial to improving the display effect of the folding screen device.

[0057] Optionally, a plurality of second microsphere particles 700 are provided in the second adhesive layer 400, and at least part of the plurality of second microsphere particles 700 are distributed in multiple layers in the second adhesive layer 400.

[0058] The above-mentioned second microsphere particles 700 may also be a core-shell structure formed by connecting a micron-sized particle with a heterogeneous outer shell through chemical bonding.

[0059] The fact that at least part of the plurality of second microsphere particles 700 are distributed in multiple layers in the second adhesive layer 400 may mean that: there are stacked second microsphere particles 700 in the thickness direction of the second adhesive layer 400, that is, there may be more than two layers of second microsphere particles 700 in the thickness direction of the second adhesive layer 400. Among them, the second microsphere particles 700 in different regions of the second adhesive layer 400 may be different. For example, please refer to Figure 7 , which is a schematic diagram of the distribution of the second microsphere particles 700 in the second adhesive layer 400 in some embodiments of the present application.

[0060] In this embodiment, a plurality of second microsphere particles 700 are provided in the second adhesive layer 400. During the folding process of the folding screen device, since the microsphere structure is not easily deformed, a thickness support effect can be formed, so that the second adhesive layer 400 is not easily thinned due to fatigue. When the folding screen device is unfolded, the microsphere structure has a certain resilience, which can assist the adhesive layer to undergo elastic deformation, thereby effectively slowing down the generation of creases. At the same time, the microsphere structure can improve the overall rigidity of the screen. In addition, since the second adhesive layer 400 is located on the non-display side of the folding screen device, therefore, by making there be stacked second microsphere particles 700 in the thickness direction of the second adhesive layer 400, that is, the number of layers of the second microsphere particles 700 in the second adhesive layer 400 is more than two layers. In this way, it is beneficial to improve the overall support and buffering effect of the folding screen, and further slow down the generation of creases.

[0061] Optionally, the second microsphere particles 700 are connected to the second adhesive layer 400 through chemical bonds.

[0062] In this embodiment, since voids will be generated when the microsphere particles are separated from the OCA adhesive layer, which will change the refractive index and scattering of light, etc., and further affect the display effect of the folding screen. Based on this, in the embodiments of the present application, by making the second microsphere particles 700 connected to the second adhesive layer 400 through chemical bonds, in this way, effective strong bonding can be formed between the microsphere particles and the adhesive layer, so that the microsphere particles and the adhesive layer are integrated. In this way, during the folding process of the folding screen device, the microsphere particles will not be separated from the adhesive layer due to weak adhesion force, thereby improving the display life of the folding screen device.

[0063] Optionally, the polarity of the material on the surface of the second microsphere particles 700 is the same as the polarity of the material of the second adhesive layer 400; and / or,

[0064] The surface of the second microsphere particles 700 has a second chemical functional group formed by chemical grafting treatment, and the second chemical functional group is connected to the second adhesive layer 400 by a chemical bond.

[0065] The fact that the polarity of the material on the surface of the second microsphere particles 700 is the same as the polarity of the material of the second adhesive layer 400 means that the type of the polarity of the material on the surface of the second microsphere particles 700 is the same as the type of the polarity of the material of the second adhesive layer 400. For example, both the type of the polarity of the material on the surface of the second microsphere particles 700 and the type of the polarity of the material of the second adhesive layer 400 are polar. Or, both the type of the polarity of the material on the surface of the second microsphere particles 700 and the type of the polarity of the material of the second adhesive layer 400 are non-polar, etc.

[0066] Specifically, the material on the surface of the second microsphere particles 700 can specifically refer to the material of the outer shell of the second microsphere particles 700. The outer shell of the second microsphere particles 700 and the second adhesive layer 400 can adopt various materials with the same polarity. Among them, the materials of the outer shell of the second microsphere particles 700 and the second adhesive layer 400 can be the same or different, as long as the polarities of the two are the same. For example, in some embodiments of the present application, the materials of the outer shell of the second microsphere particles 700 and the second adhesive layer 400 can be acrylic resins of the same material respectively.

[0067] Specifically, according to the principle of like dissolves like, the second microsphere particles 700 with the same polarity are filled into the second adhesive layer 400, and an effective strong bond is formed between the surface of the second microsphere particles 700 and the second adhesive layer 400, so that the second microsphere particles 700 and the second adhesive layer 400 are fused into one. Among them, the main principle of like dissolves like is that substances with the same polarity wet each other, rather than the traditional dissolution, that is, the outer shell of the second microsphere particles 700 will not dissolve into the second adhesive layer 400, that is, the outer shell of the second microsphere particles 700 in the second adhesive layer 400 will not dissipate. Among them, the strong bond means that a chemical bond is formed between the outer shell of the second microsphere particles 700 and the second adhesive layer 400. In this way, the second microsphere particles 700 can be connected to the second adhesive layer 400 through a chemical bond.

[0068] In some other embodiments of the present application, the polarity of the material on the surface of the second microsphere particles 700 is different from the polarity of the material of the second adhesive layer 400, and the surface of the second microsphere particles 700 has a second chemical functional group formed by chemical grafting treatment, and the second chemical functional group is connected to the second adhesive layer 400 by a chemical bond.

[0069] In some other embodiments of the present application, the polarity of the material on the surface of the second microsphere particles 700 is the same as that of the material of the second adhesive layer 400, and the surface of the second microsphere particles 700 has a second chemical functional group formed by chemical grafting treatment, and the second chemical functional group is connected to the second adhesive layer 400 by a chemical bond.

[0070] It should be noted that when the polarity of the material on the surface of the second microsphere particles 700 is different from that of the material of the second adhesive layer 400, the polarity of the material on the surface of the second microsphere particles 700 can be made similar to that of the material of the second adhesive layer 400. Since two materials with similar polarities may also form a chemical bond, this is beneficial to improving the strong bonding effect between the second microsphere particles 700 and the second adhesive layer 400. Among them, the similar polarity may mean that among the polarity of the material on the surface of the second microsphere particles 700 and the polarity of the material of the second adhesive layer 400, one is polar and the other is weakly polar.

[0071] In some embodiments of the present application, the material of the second adhesive layer 400 can be an acrylic resin to improve the comprehensive light performance of the second adhesive layer 400. The material of the outer shell of the second microsphere particles 700 can be polymethyl methacrylate (PMMA), and the material of the core of the second microsphere particles 700 can be selected from hard silica, polystyrene (PS), or hard PMMA, etc.

[0072] The above-mentioned second chemical functional group can be various types of functional groups that can form a chemical bond with the second adhesive layer 400. For example, the second chemical functional group can be a chemical functional group such as tetrabutyl titanate or siloxane. Specifically, chemical grafting treatment can be performed on the surface of the second microsphere particles 700, so that the second microsphere particles 700 can be connected to the second adhesive layer 400 by a chemical bond.

[0073] In this embodiment, by making the polarity of the material on the surface of the second microsphere particles 700 the same as that of the material of the second adhesive layer 400; and / or, the surface of the second microsphere particles 700 has a second chemical functional group formed by chemical grafting treatment, and the second chemical functional group is connected to the second adhesive layer 400 by a chemical bond, in this way, the second microsphere particles 700 can be connected to the second adhesive layer 400 by a chemical bond.

[0074] Optionally, the second microsphere particle 700 includes a second core 710 and a second outer shell 720. The second core 710 is chemically bonded to the second outer shell 720, and the elastic modulus of the second outer shell 720 ranges from 1 to 1.1 times that of the second adhesive layer 400.

[0075] In some embodiments of the present application, the elastic modulus of the second outer shell 720 can be adjusted to 1 to 1.1 times that of the second adhesive layer 400 by debugging the formula of the second outer shell 720.

[0076] In this embodiment, by making the elastic modulus of the second outer shell 720 range from 1 to 1.1 times that of the second adhesive layer 400, during the folding process of the folding screen device, the second microsphere particle 700 can undergo reversible elastic deformation, thereby absorbing the bending stress, and further avoiding the creep accumulation of the second adhesive layer 400 to slow down the generation of creases.

[0077] Optionally, the particle size of the first microsphere particle 600 is 1 / 2 to 2 / 3 times the thickness of the first adhesive layer 200; the particle size of the second microsphere particle 700 is 1 / 5 to 2 / 5 times the thickness of the second adhesive layer 400.

[0078] It can be understood that both the first microsphere particle 600 and the second microsphere particle 700 are micron-sized spherical particles.

[0079] The production of the above-mentioned first adhesive layer 200 generally includes the following steps: adding the first microsphere particle 600 to the OCA liquid adhesive, coating the OCA liquid adhesive added with the first microsphere particle 600 on the release film, rolling the liquid adhesive on the release film into a specified thickness, drying, ultraviolet (UV) curing, winding, and cutting into sheets to obtain the first adhesive layer 200. Among them, by making the particle size of the first microsphere particle 600 1 / 2 to 2 / 3 times the thickness of the first adhesive layer 200, since the sum of the particle sizes of two first microsphere particles 600 will be greater than or equal to the thickness of the first adhesive layer 200, during the rolling process, the thickness of the two overlapping first microsphere particles 600 will exceed the established limit thickness, and the protruding first microsphere particles 600 will be squeezed to the other side during the pressure rolling process, thereby ensuring that the first microsphere particles 600 in the first adhesive layer 200 are distributed in a single layer. At the same time, an appropriate amount of dispersant can be added to the formula to make the first microsphere particles 600 in the first adhesive layer 200 disperse from each other without overlap.

[0080] It should be noted that since both the first adhesive layer 200 and the second adhesive layer 400 need to undergo UV curing treatment during the manufacturing process, in order to avoid the problem that the first outer shell 620 of the first adhesive layer 200 and the second outer shell 720 of the second adhesive layer 400 dissolve in the corresponding adhesive layer during the UV curing treatment, resulting in the disappearance of the outer shell, in some embodiments of the present application, the materials of the first outer shell 620 and the second outer shell 720 can be selected as materials that do not dissolve in the OCA adhesive. For example, the materials of the first outer shell 620 and the second outer shell 720 can both be acrylic resin.

[0081] In this embodiment, by making the particle size of the first microsphere particles 600 be 1 / 2 to 2 / 3 times the thickness of the first adhesive layer 200, since the sum of the particle sizes of two first microsphere particles 600 will be greater than or equal to the thickness of the first adhesive layer 200, in this way, it is possible to avoid the stacking of the first microsphere particles 600 in the first adhesive layer 200 in the thickness direction of the first adhesive layer 200, ensuring that the first microsphere particles 600 in the first adhesive layer 200 are distributed in a single layer. At the same time, by making the particle size of the second microsphere particles 700 be 1 / 5 to 2 / 5 times the thickness of the second adhesive layer 400, in this way, it is possible to effectively control the maximum stacking layer number of the second microsphere particles 700 in the second adhesive layer 400 not to exceed 5 layers, so as to control the layer number of the second microsphere particles 700 in the human adhesive layer and improve the support effect of the second adhesive layer 400.

[0082] Optionally, in the second adhesive layer 400, the sum of the volumes of the plurality of second microsphere particles 700 is 0.01 to 0.05 times the volume of the second adhesive layer 400.

[0083] In some embodiments of the present application, during the manufacturing process of the first adhesive layer 200, the amount of the second microsphere particles 700 added is designed to be 1% - 5% of the volume ratio of the OCA adhesive.

[0084] In this embodiment, by making the sum of the volumes of the plurality of second microsphere particles 700 in the second adhesive layer 400 be 0.01 to 0.05 times the volume of the second adhesive layer 400, in this way, it is possible to make the second adhesive layer 400 have a good support effect while having a good bonding effect.

[0085] The folding screen device provided by the embodiments of the present application has at least the following beneficial effects:

[0086] The embodiments of the present application start from the OCA adhesive layer design of the crease itself, improve the creep resistance and rigidity of the OCA, can greatly improve the reliability of the ball drop and pen drop tests and optimize the crease, and prevent the crease from deepening.

[0087] With the development of folding screen technology, the OCA in the folding screen device will be further thinned. In related technologies, the effect of reducing creases by designing the outer structure of the folding screen is becoming increasingly limited. In the embodiments of the present application, the problem of creases in the folding screen device can be maintained or improved by adding a microsphere particle structure to the adhesive layer.

[0088] In the embodiments of the present application, through the layout design of different layers of OCA, the display effect can be maximally maintained without thickening the OCA, and the reliability and the appearance crease effect can be improved.

[0089] It should be noted that the folding screen device provided in the embodiments of the present application is not limited to the case of only including one first adhesive layer 200 and one second adhesive layer 400. Specifically, the number of adhesive layers can be set according to structural differences. For example, more than two first adhesive layers 200 are provided between the flexible cover plate 100 and the display layer 300, and more than two second adhesive layers 400 are provided between the display layer 300 and the support layer 500.

[0090] The embodiments of the present application also provide an electronic device, and the electronic device includes the folding screen device described in the above embodiments.

[0091] Among them, the electronic device can be various types of folding screen devices, such as folding screen mobile phones, folding screen tablet computers, etc.

[0092] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art can also make many forms without departing from the purpose of the present application and the scope protected by the claims, and all of them belong to the protection scope of the present application.

Claims

1. A folding screen device, characterized in that: include: A flexible cover plate, a first adhesive layer, a display layer, a second adhesive layer and a support layer are stacked in sequence; Wherein, a plurality of first microsphere particles are arranged in the first adhesive layer, and the plurality of first microsphere particles are distributed in a single layer in the first adhesive layer; The first microsphere particle includes a first core and a first shell. When the first microsphere particle is subjected to an external force, the elastic deformation of the first shell is greater than the elastic deformation of the first core.

2. The folding screen device according to claim 1, characterized in that: The polarity of the material on the surface of the first microsphere particle is the same as the polarity of the material of the first adhesive layer; and / or, The surface of the first microsphere particle has a first chemical functional group formed by chemical grafting treatment, and the first chemical functional group is connected to the first adhesive layer through a chemical bond.

3. The folding screen device according to claim 1, characterized in that: The elastic modulus of the first shell is in the range of 1 to 1.1 times the elastic modulus of the first adhesive layer.

4. The folding screen device according to claim 1, characterized in that: In the first adhesive layer, the distance between two adjacent first microsphere particles ranges from 50 um to 100 um.

5. The folding screen device according to claim 1, characterized in that: The refractive index of the first core, the refractive index of the first shell and the refractive index of the first adhesive layer are equal.

6. The folding screen device according to claim 1, characterized in that: A plurality of second microsphere particles are disposed in the second adhesive layer, and the plurality of second microsphere particles are distributed in multiple layers in at least a partial area of ​​the second adhesive layer.

7. The folding screen device according to claim 6, characterized in that: The particle size of the first microsphere particles is 1 / 2 to 2 / 3 times the thickness of the first adhesive layer; the particle size of the second microsphere particles is 1 / 5 to 2 / 5 times the thickness of the second adhesive layer.

8. The folding screen device according to claim 6, characterized in that: In the second adhesive layer, the sum of the volumes of the plurality of second microsphere particles is 0.01 to 0.05 times the volume of the second adhesive layer.

9. The folding screen device according to claim 6, characterized in that: The polarity of the material on the surface of the second microsphere particles is the same as the polarity of the material of the second adhesive layer; and / or, The surface of the second microsphere particle has a second chemical functional group formed by chemical grafting treatment, and the second chemical functional group is connected to the second adhesive layer through a chemical bond.

10. An electronic device, characterized in that: A folding screen device comprising any one of claims 1 to 9.

Images