Folding display film group adopting patterned adhesive layer structure and display device

Abstract

The utility model provides a folding display film group adopting a patterned adhesive layer structure, which comprises a display layer and a plurality of adhesive material layers in a bending area, different functional layers of the display layer are connected through the adhesive material layers, at least one adhesive material layer is provided with a patterned structure in the bending area, and the patterned structure comprises a plurality of grooves or holes which are arranged at intervals. According to the folding display module, the patterning structure is arranged in the bending area of the adhesive layer, bending stress is dispersed, creases generated in the bending process of the folding display module are remarkably reduced or eliminated, the display quality and user experience are improved, the stress is effectively dispersed, the risks of layering and damage of the film layer are reduced, and the service life of the folding display module is prolonged. Therefore, the bending reliability and the service life of the folding display module are improved. The technical scheme can be compatible with an existing folding display module manufacturing process, an existing production line does not need to be greatly transformed, and industrial application is easy to achieve.

Description

TECHNICAL FIELD

[0001] The utility model relates to display module structure field, concretely, relate to a kind of folding display film group and display device using patterning glue layer structure. BACKGROUND

[0002] In recent years, with the rapid development of intelligent mobile terminal, foldable electronic equipment such as folding screen mobile phone gradually becomes the research hotspot in consumer electronics field. Compared with traditional straight display screen, folding screen can significantly increase the display area of equipment, while keeping small portability, and bring new use experience for users.

[0003] One of the key technologies of folding screen is the preparation of flexible display module. Flexible display module usually includes display layer, multiple functional film layers and glue material layer for bonding each layer of film. In order to realize foldability, these film layers need to have good flexibility and bending performance. However, in the process of frequent bending, the traditional plane glue layer is easy to produce stress concentration in the bending area, which causes the film layer to have fold, delamination and even damage, seriously affecting the display effect and equipment life. Specifically, in the traditional folding display module, each layer of film is bonded by continuous glue layer. When the module is bent, the glue layer in the bending area will be subjected to large tensile and compressive stress. Because the glue layer itself has a certain rigidity, it cannot fully adapt to the bending deformation, resulting in stress concentration. This stress concentration will be transmitted to other film layers, such as display layer, polarizer, etc., eventually leading to the generation of fold. In addition, repeated bending will also cause the adhesion between the glue layer and the film layer to decrease, resulting in delamination.

[0004] It should be noted that the information disclosed in the above background section is only used to strengthen the understanding of the background of the utility model, and therefore can include information that does not constitute prior art known to those skilled in the art. UTILITY MODEL CONTENT

[0005] Therefore, the utility model provides a kind of folding display film group and display device using patterning glue layer structure to overcome the defects such as fold, delamination caused by stress concentration of glue layer in the bending process of folding display module in prior art, by setting patterning structure in the bending area of at least one glue material layer, to disperse bending stress, thereby reducing or eliminating the generation of fold, improve the reliability and service life of folding display module.

[0006] One aspect of the utility model provides a kind of folding display film group using patterning glue layer structure, including the display layer and multiple glue material layers of bending area, the different functional layers of display layer are connected by glue material layer, at least one glue material layer has patterning structure in bending area, and patterning structure includes multiple spaced recesses or holes.

[0007] In some optional embodiments, the patterned structure is at least one selected from the following patterns: strip, net, honeycomb, wave, zigzag, circle, ellipse, triangle, polygon.

[0008] In some optional embodiments, the depth of the groove or hole of the patterned structure is not less than 10% of the thickness of the adhesive layer.

[0009] In some optional embodiments, the plurality of adhesive layers comprises at least two adhesive layers, and the at least two adhesive layers each have a patterned structure in the bending area.

[0010] In some optional embodiments, the patterned structures of the at least two adhesive layers are arranged in a staggered manner.

[0011] In some optional embodiments, the display layer comprises an OLED display layer.

[0012] In some optional embodiments, a support layer is further included, and the at least one adhesive layer is arranged between the display layer and the support layer.

[0013] In some optional embodiments, the support layer comprises a glass substrate, a plastic substrate or a metal substrate.

[0014] In some optional embodiments, the adhesive layer is an optically transparent adhesive.

[0015] Another aspect of the utility model also provides a folding display device, and the display device comprises the folding display film group adopting the patterned adhesive layer structure.

[0016] Compared with the prior art, the utility model at least has the following advantages:

[0017] Compared with the prior art, the folding display film group adopting the patterned adhesive layer structure of the utility model has the beneficial technical effects as follows:

[0018] The creases are effectively reduced or eliminated. By arranging the patterned structure in the bending area of the adhesive layer, the bending stress is dispersed, the creases generated in the folding process of the folding display module are significantly reduced or eliminated, and the display quality and user experience are improved.

[0019] The bending reliability is improved. Since the stress is effectively dispersed, the risk of delamination and damage of the film layer is reduced, and thus the bending reliability and service life of the folding display module are improved.

[0020] The compatibility is good. The technical scheme of the utility model can be compatible with the existing folding display module manufacturing process, without the need of making substantial modification to the existing production line, and is easy to realize industrial application.

[0021] Design flexibility. The shape, size, pitch, etc. of the patterned structure can be flexibly adjusted according to actual needs to achieve the best stress dispersion effect.

[0022] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0023] The drawings incorporated in the specification and forming a part thereof illustrate embodiments consistent with the utility model and, together with the description, serve to explain the principles of the utility model. Obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained from these drawings without creative labor.

[0024] Figure 1 A cross-sectional schematic view of a folding display film set provided by the utility model is shown;

[0025] Figure 2 A strip patterned structure schematic view provided in one specific embodiment of the utility model is shown;

[0026] Figure 3 A mesh patterned structure schematic view provided in one specific embodiment of the utility model is shown. DETAILED DESCRIPTION

[0027] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations, however, can be implemented in many different forms and should not be construed as limited to the implementations set forth herein. Rather, these implementations are provided as example (s) so that this disclosure will be thorough and complete, and will fully convey the scope of example implementations to those skilled in the art. Like reference numerals refer to like elements throughout the drawings, and descriptions of the same elements will not be repeated.

[0028] The terms "first", "second", and similar terms used in the description and claims of the utility model are not intended to denote any order, quantity, or importance, but are only used to distinguish different components. In addition, in the description of the utility model, the orientation or position relationship indicated by the terms "upper", "lower", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model.

[0029] The utility model is based on the patterned design of the adhesive layer in the flexible display film set, especially the local patterned treatment in the bending area, so as to optimize the stress distribution generated in the bending process. For example Figure 1As shown, the utility model provides a kind of cross section structure of folding display module, film layer structure is in turn hard coating (HC), PET base material, optical transparent adhesive (OCA), ultra-thin glass (UTG), optical transparent adhesive (OCA), polaroid (Pol), OLED panel (Panel), support film (Support film), optical transparent adhesive (OCA) and stainless steel substrate (SUS).Wherein, as the OCA of adhesive material layer as adhesive, each layer film layer is tightly combined together.In the folding process of folding display module, when Figure 1When the multi-layer structure is bent, the materials in the bending area will be subjected to different degrees of tensile and compressive stress. With the bending center line as the boundary, the materials on the outside are subjected to tensile stress, and the materials on the inside are subjected to compressive stress. The size of the stress is related to the bending degree, the elastic modulus of each layer of material, and the position of each layer of material in the structure, etc. Because the adhesive layer connects materials with different moduli (such as UTG and OLED panel), the deformation degree of each layer of material is different when bending, which will generate a large shear stress in the OCA adhesive layer. When the module is bent, the continuous OCA adhesive layer will form a significant stress concentration in the bending area, especially in the OCA adhesive layer between the UTG and the OLED panel. This stress concentration will first cause the problem of excessively high stress peak value, and the stress value of the OCA adhesive layer in the bending area is much higher than that in other areas, which is easy to exceed the bonding strength of the OCA adhesive layer or the bending strength of the UTG, causing the OCA adhesive layer and the adjacent film layer to peel off, or the UTG to break, thereby producing a fold or a crack. Secondly, it will also cause the problem of stress transmission, that is, the stress in the OCA adhesive layer will be transmitted to the adjacent film layer, especially the OLED panel which is sensitive to bending stress, causing the OLED panel to also deform, further aggravating the generation of folds, and even affecting the display effect. Therefore, to solve the fold problem of the folding display module, the key lies in how to effectively disperse the stress in the bending area, reduce the stress peak value, and reduce the transmission of stress between different film layers. The introduction of discontinuous structures such as grooves or holes in the adhesive layer can change the stress distribution state of the adhesive layer in the bending area. Specifically, the presence of grooves or holes will first change the stress transmission path, the discontinuity of the adhesive layer is interrupted, so that the stress cannot be directly transmitted like in the continuous adhesive layer, but needs to bypass the grooves or holes for transmission, thereby dispersing the stress. Secondly, it can also reduce local stress concentration, the stress value around the grooves or holes is relatively low, avoiding the stress concentration in a single area, and reducing the stress peak value. Furthermore, it can provide a deformation space, the grooves or holes provide an additional deformation space for the adhesive layer to some extent, so that the adhesive layer can better adapt to deformation when bending, reducing the stress caused by mismatched deformation. In summary, by setting a patterned structure containing a plurality of spaced grooves or holes in the adhesive layer, the bending stress can be effectively dispersed, the stress peak value can be reduced, and the transmission of stress between different film layers can be reduced, thereby reducing or eliminating the folds generated in the folding display module during the bending process, and improving the bending performance and reliability of the module.

[0030] The utility model provides a kind of folding display film group using patterning glue layer structure, including the display layer of bending area and multiple glue material layers, at least one glue material layer has patterning structure in bending area, patterning structure includes multiple interval arrangement's recess or hole.In folding display module, bending area refers to the area that is bent and deformed in folding state.Its bending performance directly determines the reliability and service life of module.In the utility model, bending area refers to the predetermined area that is bent when folding display film group is used, and this area is not absolute geometric area, but is determined according to product design and use mode.For example, for folding folding screen mobile phone, bending area is usually located Figure 1 Center position of UTG, Pol, Panel, Support film and OCA glue layer among them;For flip folding screen mobile phone, bending area is located at the hinge connection of screen, and correspondingly also corresponds to relevant film layer and glue layer in Figure 1 Display layer is mainly composed of polarizing sheet (Pol) and OLED panel (Panel), and OLED panel is the core of self-luminous display device, and polarizing sheet is used to improve display contrast and visibility.In the utility model, display layer aims to realize image display function, and can include other necessary film layers, such as touch layer, protective layer, etc., but is not limited to the structure shown in Figure 1 Glue material layer refers to adhesive layer for bonding different functional layers in display layer and bonding display layer and other film layers.Combined with Figure 1 , glue material layer is respectively located at the connecting glue material layer above PET substrate, OCA glue material layer between PET and UTG, OCA glue material layer between UTG and Pol, connecting glue material layer between Pol and Panel and OCA glue material layer between Support film and SUS, for firmly bonding each layer film layer together.Glue material layer needs to have good optical performance (such as high light transmittance, low haze), bonding performance and flexibility to ensure the display effect and reliability of display module.In the utility model, glue material layer is preferably optical clear adhesive (OCA), which has excellent optical performance and bonding strength, but other adhesives suitable for flexible display, such as pressure sensitive adhesive (PSA), hot melt adhesive, etc., are not excluded.Patterning structure refers to recessed or convex structure with specific pattern formed on the surface of glue material layer.In the utility model, patterning structure specifically refers to the structure including multiple interval arrangement's recess or hole formed in the bending area of at least one glue material layer.Combined with Figure 1The patterned structure can be located in any one of the adhesive layers, and is particularly preferably located in the OCA adhesive layer between the UTG and the Pol and the OCA adhesive layer between the SUS and the Support film, because the two adhesive layers bear greater stress when being bent. The structure changes the stress distribution state of the adhesive layer in the bending area by introducing discontinuity in the adhesive layer. The groove refers to a trench-shaped depression formed on the surface of the adhesive layer, and the hole refers to a through hole penetrating through the adhesive layer. The groove and the hole can be regular or irregular in shape, such as strip-shaped, rectangular, circular, elliptical, polygonal, etc. The spaced arrangement means that there is a certain spacing between the grooves or holes, and they are not arranged continuously. The size of the spacing needs to be designed according to the specific application scenario and material properties to achieve the best stress dispersion effect. At least one of the adhesive layers has a patterned structure in the bending area, that is, not all of the adhesive layers need to have a patterned structure, but at least one of the adhesive layers needs to have a patterned structure in the bending area. In combination with the foregoing technical principles, Figure 1 For example, the patterned structure can be provided only in the OCA adhesive layer between the UTG and the Pol, or simultaneously in the OCA adhesive layers between the UTG and the Pol and between the SUS and the Support film, or in the connecting adhesive layer on the PET substrate, or in the connecting adhesive layer between the Pol and the Panel. This design maximizes the dispersion of bending stress while ensuring adhesion strength. In combination with the foregoing technical principles, in the bending process, the continuous adhesive layer will form stress concentration in the bending area, resulting in excessively high stress peaks and transmitting to the adjacent film layers, thereby generating folds. However, the present application changes the continuity of the adhesive layer in the bending area by providing a patterned structure containing a plurality of spaced grooves or holes in at least one of the adhesive layers in the bending area, so that the stress cannot be transmitted directly as in the continuous adhesive layer, but needs to bypass the grooves or holes, increasing the path of stress transmission and thereby dispersing the stress. At the same time, the stress value around the grooves or holes is relatively low, avoiding stress concentration in a single area and reducing the stress peaks. In addition, the grooves or holes provide additional deformation space for the adhesive layer to some extent, so that the adhesive layer can better adapt to deformation when being bent, reducing the stress caused by mismatched deformation. Through the above means, the stress concentration in the bending area is effectively reduced.

[0031] The present application can effectively disperse bending stress, reduce stress peaks, and reduce the transmission of stress between different film layers, thereby reducing or eliminating the folds generated in the folding process of the folding display module, and improving the bending performance and reliability of the module. Those skilled in the art can select grooves or holes of different shapes, sizes and spacings according to actual needs, and design the patterned structure in different adhesive layers according to the actual application scenario and material properties to achieve the best stress dispersion effect. Figure 1The patterned structure is arranged on the adhesive material layer including the OCA adhesive layer in different positions. The above embodiments are only exemplary and should not be construed as limiting the utility model.

[0032] In some embodiments, the patterned structure is at least one selected from the following patterns: strip, mesh, honeycomb, wavy, zigzag, circle, ellipse, triangle, polygon. Different patterned structure types represent different stress dispersion ways and deformation buffering effects. For example, Figure 2 As shown, the strip patterned structure refers to forming a series of parallel or approximately parallel grooves or protrusions on the surface of the adhesive layer, and the grooves or protrusions are in strip or line shape. The advantages of the strip patterned structure are relatively simple processing and effective dispersion of stress along the bending direction. In the embodiments of the utility model, the strip refers to a groove or hole with a length much greater than the width, and the length direction is substantially parallel to the bending direction, and the width direction is perpendicular to the bending direction. The cross-sectional shape of the strip can be rectangular, trapezoidal, semicircular, etc. For example, Figure 3As shown, the mesh patterned structure refers to forming interlaced grooves or protrusions on the surface of the adhesive layer, forming a grid structure. The mesh patterned structure can more evenly disperse stress in all directions, providing better deformation buffering effect. In the embodiments of the present application, the mesh patterned structure refers to a grid structure composed of interlaced strip grooves or holes, such as square grid, rectangular grid, diamond grid, etc. The honeycomb patterned structure refers to forming hexagonal or approximately hexagonal grooves or protrusions on the surface of the adhesive layer. The honeycomb patterned structure has excellent mechanical properties and can effectively withstand stress in all directions. The wave patterned structure refers to forming a continuous wave-shaped concave-convex structure on the surface of the adhesive layer. The wave patterned structure can effectively absorb the stress generated by bending deformation and has good flexibility. The sawtooth patterned structure refers to forming a series of sawtooth-shaped concave-convex structures on the surface of the adhesive layer. The sawtooth patterned structure can limit the bending direction to a certain extent and improve the stability of bending. The circular, elliptical, triangular, polygonal patterned structure refers to forming grooves or holes with corresponding shapes on the surface of the adhesive layer. These shapes can be used alone or in combination to achieve a specific stress dispersion effect. In the embodiments of the present application, the circular, elliptical, triangular, polygonal patterned structure refers to the top view shape of the groove or hole. Different patterned structures correspond to different stress dispersion and deformation buffering mechanisms. For example, the strip patterned structure mainly disperses stress along the bending direction, while the mesh patterned structure can more evenly disperse stress in all directions. Selecting the appropriate patterned structure needs to be balanced according to the specific application scenario and material properties. The preferred patterned structure is the strip patterned structure or the mesh patterned structure, because these two structures have achieved a good balance between processability and stress dispersion effect. Different patterned structures can achieve different stress dispersion and deformation buffering effects, thereby better reducing or eliminating the creases generated during the folding process of the folding display module, and the appropriate pattern type can be selected according to the specific application scenario to achieve the best performance.

[0033] By selecting different patterned structures, the effects of stress dispersion and deformation buffering can be more flexibly controlled, thereby further optimizing the bending performance and reliability of the foldable display module. For example, using a mesh patterned structure can better cope with multi-directional bending stress and improve the fatigue resistance of the module. Using a strip patterned structure can simplify the processing technology while ensuring the stress dispersion effect. Therefore, the utility model provides greater flexibility and optimization space for the design and manufacture of the foldable display module by providing a variety of selectable patterned structures. Those skilled in the art can select one or more of the above patterns according to actual needs for combination, such as combining strip and mesh patterns, or combining circular and polygonal patterns. In addition, other shaped patterned structures can also be designed according to needs, such as irregular shaped patterns. The above embodiments are only exemplary and should not be construed as limiting the utility model.

[0034] In some embodiments, the depth of the grooves or holes of the patterned structure is not less than 10% of the thickness of the adhesive layer. In the embodiments of the utility model, the depth refers to the vertical distance of the groove or hole from the surface of the adhesive layer to the downward recess or penetration. For grooves, the depth refers to the vertical distance from the bottom of the groove to the surface of the adhesive layer; for holes, the depth is the thickness of the adhesive layer. The thickness of the adhesive layer refers to the original thickness of the adhesive layer before the patterned structure is formed. The thickness varies according to different application scenarios and material properties. The depth of the groove or hole should at least reach 10% of the thickness of the adhesive layer. If the depth is too small, it is difficult to effectively change the stress distribution state of the adhesive layer in the bending area, and the stress dispersion and deformation buffering effect is not obvious; if the depth is too large, it may affect the bonding strength of the adhesive layer, and even cause separation between the film layers. Therefore, it is very important to select the appropriate depth ratio. Preferably, the depth of the groove or hole can be selected within the range of 10% to 50% of the thickness of the adhesive layer, more preferably within the range of 20% to 40%. For example, if the thickness of the adhesive layer is 10 microns, the depth of the groove or hole should be not less than 1 micron, preferably between 2 microns and 4 microns. The depth of the groove or hole directly affects the effects of stress dispersion and deformation buffering. The greater the depth, the greater the damage to the continuity of the adhesive layer, and the more obvious the stress dispersion effect, but at the same time, it will also reduce the effective bonding area of the adhesive layer. Therefore, according to the specific application scenario and material properties, the relationship between stress dispersion effect and bonding strength needs to be balanced, and the appropriate depth ratio needs to be selected.

[0035] By limiting the depth of the grooves or holes to no less than 10% of the thickness of the adhesive layer, it can be ensured that the patterned structure can effectively play a role, achieve the expected stress dispersion and deformation buffering effect, thereby effectively reducing or eliminating the creases generated in the folding process of the folding display module, improving the folding reliability and service life of the module. At the same time, by reasonably controlling the depth ratio, the adhesive strength of the adhesive layer can be maximized while ensuring the stress dispersion effect, avoiding separation between the film layers. Those skilled in the art can select different depth ratios according to actual needs, for example, the depth of the grooves or holes can be optimized according to different adhesive layer materials and thicknesses, as well as different bending radii and bending frequencies, etc. The above embodiments and preferred ranges are only exemplary and should not be construed as limiting the present application. For example, in some special application scenarios, the depth of the grooves or holes can also be greater than 50% of the thickness of the adhesive layer, or even close to or equal to the thickness of the adhesive layer, forming a completely penetrating hole.

[0036] In some embodiments, the plurality of adhesive layers includes at least two adhesive layers, and the at least two adhesive layers have patterned structures in the bending area. Figure 1 As shown, the adhesive layers include a connecting adhesive layer on the PET substrate, an OCA adhesive layer between the PET and the UTG, an OCA adhesive layer between the UTG and the Pol, a connecting adhesive layer between the Pol and the Panel, and an OCA adhesive layer between the Support film and the SUS, for firmly bonding the film layers together. By providing at least two adhesive layers with patterned structures, the stress dispersion and deformation buffering effect can be further enhanced. When bending occurs, stress will be transmitted to each layer of adhesive layer in turn. During the bending process, stress will be transmitted between each layer of adhesive layer. By providing multiple layers of adhesive layers with patterned structures, multiple stress dispersion and collaborative buffering can be achieved, thereby more effectively reducing the stress concentration in the bending area and further reducing or eliminating the generation of creases. Compared to only one adhesive layer having a patterned structure, which can only perform stress dispersion once. If there are multiple adhesive layers with patterned structures, multiple stress dispersion can be performed, thereby more effectively reducing the stress peak. The patterned structures in different adhesive layers can work together to buffer the bending deformation. For example, the grooves or holes in different layers can be arranged in a staggered manner to form a more complex stress transmission path, thereby more effectively dispersing stress. Alternatively, the patterned structures in different layers can have different parameters (such as shape, size, spacing, etc.) to adapt to different deformation requirements.

[0037] By setting at least two layers of adhesive material layers with patterned structures in the bending area, more excellent stress dispersion and deformation buffering effect can be achieved, thereby more effectively reducing or eliminating the creases generated in the folding process of the folding display module, significantly improving the folding reliability and service life of the module, and the position and number of the adhesive material layers with patterned structures and the specific parameters of the patterned structures can be flexibly selected according to the specific application scene and design requirements to achieve the best performance. Those skilled in the art can select at least two layers of OCA adhesive layers with patterned structures at different positions according to actual needs. Figure 1 For example, patterned structures can be set on the OCA adhesive layers between the UTG and the Pol and between the SUS and the Support film, or patterned structures can be set on other two layers of adhesive material layers or more layers of adhesive material layers. In addition, the patterned structures in different adhesive material layers can be the same or different, for example, the shape, size, pitch and other parameters can be the same or different. The above embodiments are only exemplary and should not be construed as limiting the present application.

[0038] In some embodiments, the patterned structures of the at least two layers of adhesive material layers are set in a staggered manner. Staggered setting means that the projections of the patterned structures on the at least two layers of adhesive material layers in the direction perpendicular to the film layer do not completely coincide, that is, at least part of the grooves or holes are not directly opposite between different layers. In combination with the above description of the patterned structures, the staggered setting of the patterned structures can further improve the stress dispersion and deformation buffering effect, thereby more effectively reducing or eliminating the creases generated in the folding process of the folding display module, significantly improving the folding reliability and service life of the module. Figure 1The structures shown are examples. The OCA adhesive layer between the UTG and the Pol (hereinafter referred to as the first OCA layer) and the OCA adhesive layer between the SUS and the Support film (hereinafter referred to as the second OCA layer) are both provided with a patterned structure. If the grooves or holes in the first OCA layer are completely aligned with the grooves or holes in the second OCA layer, the stress will still be transmitted along the same path, and the stress dispersion effect may not be ideal. By misaligning, the transmission path of the stress can be changed, achieving more effective stress dispersion. The specific way of misalignment can be various: translational misalignment, which is to translate the patterned structure on one layer of adhesive relative to the patterned structure on the other layer of adhesive, so that the grooves or holes are offset in the horizontal direction. Rotational misalignment, which is to rotate the patterned structure on one layer of adhesive relative to the patterned structure on the other layer of adhesive, so that the arrangement direction of the grooves or holes has a certain angle difference. Combined misalignment, which combines translational misalignment and rotational misalignment, so that the relative position of the grooves or holes is more complex, thereby achieving a more optimal stress dispersion effect. By misaligning the patterned structures of at least two layers of adhesive, more effective stress dispersion can be achieved, the stress peak can be reduced, and the transmission of stress between different film layers can be reduced, thereby more significantly reducing or eliminating the creases generated in the folding process of the folding display module, and further improving the folding performance and reliability of the module. In addition, misalignment can also enable the patterned structures in different layers to form mutual support, improving the overall strength of the structure. Those skilled in the art can select different misalignment methods and misalignment amounts according to actual needs. For example, the misalignment method and misalignment amount can be optimized according to different pattern shapes, sizes, and pitches, as well as different bending radii and bending frequencies, and other parameters. The above embodiments are only exemplary and should not be construed as limiting the present application. For example, although misalignment is preferred, in some special application scenarios, a partially aligned arrangement method can also be used.

[0039] In some embodiments, the display layer includes an OLED display layer. OLED (Organic Light-Emitting Diode) is an organic electroluminescent device with the advantages of self-luminescence, no need for a backlight, high contrast, fast response speed, wide viewing angle, thin thickness, flexible display, etc., and is suitable for folding display devices. The display layer is a film layer for displaying images and can include multiple functional layers. By using an OLED display layer, the folding display film module of the present application can have good display performance and bending performance, better meeting the needs of folding display devices. Although the present embodiment preferably uses an OLED display layer, the present application is not limited thereto. In other embodiments, the display layer can also use other types of display technology, such as Micro-LED, quantum dot display, etc. The above embodiments are only exemplary and should not be construed as limiting the present application.

[0040] In some embodiments, the folding display module further comprises a support layer, and the at least one adhesive layer is arranged between the display layer and the support layer. The main function of the support layer is to provide mechanical support for the display layer, enhance the overall strength and stability of the module, especially in the bent state, and effectively protect the display layer from damage. The support layer usually needs to have good flexibility, bending resistance and dimensional stability. The material of the support layer can be flexible materials such as polyimide (PI), polyethylene terephthalate (PET), polycarbonate (PC), etc. In the embodiments of the present application, the support layer aims to provide mechanical support for the display layer, and can include other necessary film layers, such as hardening layer, functional coating layer, etc., but is not limited to the structure shown. Figure 1 By setting the support layer and using at least one adhesive layer to bond it with the display layer, the overall strength and stability of the folding display module can be improved, especially in the bent state, which can effectively protect the display layer from damage, and in combination with the patterned structure of the adhesive layer, the bending performance and reliability of the module are further improved.

[0041] In some embodiments, the support layer comprises a glass substrate, a plastic substrate or a metal substrate. In the embodiments of the present application, the glass substrate has excellent dimensional stability, optical performance (such as high light transmittance, low thermal expansion coefficient) and weather resistance, and is often used in traditional display panels. However, the traditional glass substrate does not have flexibility and is difficult to meet the needs of folding display. Therefore, in the embodiments of the present application, if the glass substrate is used as the support layer, it usually refers to ultra-thin glass (UTG, Ultra-Thin Glass). The UTG is subjected to special thinning and strengthening treatment and has a certain flexibility, which can be applied to folding display devices. For example, Figure 1The middle UTG is a glass substrate. Plastic substrates have good flexibility, lightness and easy processability, and are commonly used as support layer materials in folding display devices. Commonly used plastic substrate materials include polyimide (PI), polyethylene terephthalate (PET), polycarbonate (PC), polyetherimide (PEI), etc. Among them, PI substrate has excellent high temperature resistance, chemical resistance and mechanical properties, and is one of the most commonly used substrate materials in the field of flexible display. Metal substrates have high strength, high rigidity and good thermal conductivity, which can provide better mechanical protection and heat dissipation performance for the display module. Commonly used metal substrate materials include stainless steel, aluminum alloy, etc. The metal substrate usually needs to be subjected to special surface treatment to improve its adhesion with other film layers. Since the metal substrate has good ductility and certain flexibility, it can be applied to folding display devices, but usually needs to be used together with other flexible materials. The main function of the support layer is to provide mechanical support for the display layer and enhance the overall strength and stability of the module. Different substrate materials have different properties and need to be selected according to specific application scenarios and performance requirements. For example, if the bending performance requirement is high, a plastic substrate is preferred; if the display effect and dimensional stability requirement is high, UTG can be considered; if the mechanical strength and heat dissipation performance requirement is high, a metal substrate can be considered. By selecting a suitable substrate material as the support layer, the folding display module of the utility model has good mechanical strength, flexibility, dimensional stability and display effect, so as to better meet the needs of folding display devices and improve user experience. Those skilled in the art can select other types of substrate materials according to actual needs, such as composite material substrates, etc. In addition, various surface treatments can be performed on the substrate, such as hardening treatment, anti-reflection treatment, functional coating, etc., to improve its performance. The above embodiments are only exemplary and should not be construed as limiting the utility model.

[0042] In some embodiments, the adhesive layer is an optically clear adhesive. OCA (Optically Clear Adhesive) is a special adhesive with high light transmittance and low haze, mainly used for bonding optical elements. In the folding display module, the adhesive layer not only needs to firmly bond the various film materials together, but also needs to ensure good optical performance to avoid affecting the display effect. In the folding display module, the adhesive layer not only needs to play a bonding role, but also needs to ensure good optical performance. By using optically clear adhesive, light loss and scattering can be minimized to ensure the brightness, clarity and contrast of the display picture. Those skilled in the art can select different types and specifications of OCA according to actual needs, such as selecting appropriate OCA according to different substrate materials, bonding strength requirements and optical performance requirements. The above embodiments are only exemplary and should not be construed as limiting the utility model.

[0043] The folding display device provided by the folding display film group with the patterned adhesive layer structure of the utility model can significantly improve the display effect, bending reliability and service life of the device, thereby improving the user experience.

[0044] It should be noted that the embodiments of the utility model and the features in different embodiments can be combined with each other without conflict.

[0045] The above content is a further detailed description of the utility model in combination with specific preferred embodiments, and the specific implementation of the utility model cannot be limited to these descriptions. For ordinary skilled persons in the technical field to which the utility model belongs, some simple deductions or substitutions can be made without departing from the concept of the utility model, and all of them should be regarded as falling within the protection scope of the utility model.

Claims

1. A foldable display film set with a patterned adhesive layer structure, comprising a display layer of a bending area and a plurality of adhesive material layers, characterized in that, The different functional layers of the display layer are connected by adhesive layers, at least one of the adhesive layers has a patterned structure in the bending area, and the patterned structure comprises a plurality of spaced recesses or holes. 2.The foldable display film set employing the patterned adhesive layer structure of claim 1, wherein, The patterned structure is at least one selected from the following patterns: strip, net, honeycomb, wave, zigzag, circle, ellipse, triangle, polygon. 3.The foldable display film set employing the patterned adhesive layer structure of claim 1, wherein, The depth of the recesses or holes of the patterned structure is not less than 10% of the thickness of the adhesive layer. 4.The foldable display film set employing the patterned adhesive layer structure of claim 1, wherein, The plurality of adhesive layers comprises at least two adhesive layers, and the at least two adhesive layers each have a patterned structure in the bending area. 5.The foldable display film set employing the patterned adhesive layer structure of claim 4, wherein, The patterned structures of the at least two adhesive layers are arranged in a staggered manner. 6.The foldable display film set employing the patterned adhesive layer structure of claim 1, wherein, The display layer comprises an OLED display layer. 7.The foldable display film set employing the patterned adhesive layer structure of claim 1, wherein, Further comprising a support layer, and at least one of the adhesive layers is arranged between the display layer and the support layer. 8.The foldable display film set employing the patterned adhesive layer structure of claim 7, wherein, The support layer comprises a glass substrate, a plastic substrate or a metal substrate. 9.The foldable display film set employing the patterned adhesive layer structure of claim 1, wherein, The adhesive layer is an optically transparent adhesive.

10. A foldable display device, characterized by comprising: The display device comprises the folding display film group with the patterned adhesive layer structure according to any one of claims 1-9.

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