Adhesive layer structure and adhesive film, display device

Abstract

The utility model discloses a kind of laminated glue layer structure and laminated film, display device, it is related to optical film technical field.The laminated glue layer structure includes: a first substrate layer;A microstructure laminated layer is sequentially orderly arrayed on the first substrate layer along preset direction immediately;Wherein, the microstructure laminated layer is multiple linear columnar prism structure, to form discontinuous lamination surface.The utility model, solve the luminance promotion scheme of various laminated films of existing, all with redesign lower prism layer microstructure collocation as main, such composite microstructure, although can be protected by structure height difference to low prism peak end, but the mold processing of composite microstructure is time-consuming and laborious, greatly improve mold manufacturing cost, not conducive to the cost control problem of mass production.

Description

Technical Field

[0001] This utility model relates to the field of optical film technology, and in particular to a bonding adhesive layer structure, bonding film, and display device. Background Technology

[0002] Currently, it is common practice in the display backlight module industry to manufacture prism sheets in the form of lamination films. The purpose is to reduce the thickness of the PET substrate for each optical film layer to reduce costs and improve the convenience of assembly.

[0003] Existing solutions for enhancing the brightness of laminated films primarily rely on redesigning the microstructure of the lower prism layer. While this composite microstructure can protect the low-profile prism peaks through structural height differences, the mold processing of such composite microstructures is time-consuming and labor-intensive, significantly increasing mold manufacturing costs and hindering cost control for mass production. Currently, no effective solution has been proposed to address these issues. Utility Model Content

[0004] Purpose of the utility model: To provide a bonding adhesive layer structure, bonding film, and display device, so as to at least solve one of the problems existing in the prior art.

[0005] Technical solution: A bonding adhesive layer structure, comprising: A first substrate layer; and A microstructure bonding layer is sequentially and orderly arranged in a close array on the first substrate layer along a preset direction; The microstructure bonding layer consists of a plurality of linear columnar prism structures to form a discontinuous bonding surface.

[0006] Preferably, the prism base width of the columnar prism structure is ≤20μm, the prism height is ≤5μm, and the top of the prism is arc-shaped.

[0007] Preferably, the bottom width of the cylindrical prism is 5μm-20μm, and the height of the prism is 3μm-5μm.

[0008] Preferably, the refractive index of the microstructure bonding layer is 1.35-1.7.

[0009] Preferably, a first prism layer is provided on the side of the microstructure bonding layer away from the first substrate layer, and the tip of the first prism layer is bonded to the microstructure bonding layer; The extension direction of the microstructure bonding layer is at a predetermined angle to the extension direction of the first prism layer.

[0010] Preferably, the included angle is 30°-90°.

[0011] Preferably, a second substrate layer is provided on the side of the first prism layer away from the microstructure bonding layer; Wherein, the first substrate layer and the second substrate layer are any one of PMMA, TAC, PET, COP, PP, TPU or PE.

[0012] Preferably, a diffusion layer is disposed on the side of the first substrate layer away from the microstructure bonding layer to form an optical film with a DOP structure; or, A microlens structure is disposed on the side of the first substrate layer away from the microstructure bonding layer to form an optical film with an MOP structure; or, A second prism layer is disposed on the side of the first substrate layer away from the microstructure bonding layer, and the extension direction of the second prism layer and the first prism layer are preset to form an angle to form an optical film with a POP structure.

[0013] Preferably, the second substrate layer has a back coating layer on the side away from the first prism layer.

[0014] To achieve the above objectives, according to another aspect of this application, a display device is also provided.

[0015] The display device according to this application includes the aforementioned bonding film.

[0016] Beneficial effects: In the embodiments of this application, an optimized bonding layer structure is adopted. By setting the microstructure bonding layer as a plurality of linear columnar prism structures to form a discontinuous bonding surface, the discontinuous bonding surface is locally adhered to the tip of the first prism layer. This achieves the technical effect of obtaining a bonding state with a smaller degree of damage to the prism peak. This solves the technical problem that various existing bonding film brightness enhancement schemes mainly rely on redesigning the microstructure of the lower prism layer. Although such a composite microstructure can protect the low prism peak by means of structural height difference, the mold processing of the composite microstructure is time-consuming and labor-intensive, which greatly increases the mold manufacturing cost and is not conducive to cost control during mass production. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the adhesive layer structure of this utility model; Figure 2 This is a schematic diagram of the bonding layer and the lower brightening layer of this utility model; Figure 3 This is a schematic diagram of the DOP structure prepared using the bonding layer of this utility model; Figure 4 This is a schematic diagram of the MOP structure prepared using the bonding layer of this invention; and Figure 5This is a schematic diagram of a POP structure prepared using the bonding layer of this utility model.

[0018] The attached figures are labeled as follows: 10. First substrate layer; 20. Microstructure bonding layer; 30. First prism layer; 40. Second substrate layer; 50. Diffusion layer; 60. Microlens structure; 70. Second prism layer. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0021] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this utility model based on the specific circumstances.

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] like Figure 1-5As shown, this application relates to a bonding adhesive layer structure, a bonding film, and a display device. Figure 1 As shown, the adhesive layer structure includes: a first substrate layer 10; the first substrate layer 10 refers to the support of the adhesive film, which can achieve good fixation and support effects, thereby ensuring the stability of the structure; it is usually a transparent, flexible polymer film with certain strength and stability.

[0024] A microstructure bonding layer 20 is arranged in a sequential and orderly array on the first substrate layer 10 along a preset direction; this ensures a good arrangement effect, thereby ensuring excellent optical performance; at the same time, it can also achieve a good cooperation effect with other components.

[0025] The preset direction can be the X-axis or Y-axis direction in the two coordinate system; the direction can be set according to actual use needs, and is not limited in this application.

[0026] The microstructure bonding layer 20 consists of a plurality of linear columnar prism structures to form a discontinuous bonding surface.

[0027] Specifically, the layer is formed by a periodic array of multiple linear microstructure units with semi-circular cross-sections arranged along a single axis.

[0028] The linear microstructure units typically have a semi-circular cross-section, which can be of various radii of curvature, and are arranged closely on the first substrate layer 10 in a parallel and equally spaced manner.

[0029] This microstructure layer forms the final bonding interface of the device. Because this interface is composed of ridges of columnar prism structure, its physical contact with the surface of the object being bonded is intermittent, thus it is a discontinuous bonding surface.

[0030] This application also has the following beneficial effects: The adhesive layer is configured with a microstructure extending in a predetermined unidirectional direction. On one hand, by locally adhering the discontinuous adhesive surface to the prism structure, a bonding effect is achieved with minimal damage to the prism peaks. On the other hand, this linear microstructure also provides additional optical effects, particularly in terms of interference resistance control, brightness enhancement, and viewing angle control. It can be applied to various types of laminated brightness enhancement films, including DOP, MOP, POP, and DPP.

[0031] As can be seen from the above description, this application achieves the following technical effects: In this embodiment, an optimized bonding layer structure is adopted. By setting the microstructure bonding layer 20 into a plurality of linear columnar prism structures, a discontinuous bonding surface is formed. This achieves the purpose of localized adhesion of the discontinuous bonding surface to the tip of the first prism layer 30, thereby achieving the technical effect of obtaining a bonding state with a smaller degree of damage to the prism peak. This solves the technical problem that existing bonding film brightness enhancement schemes mainly rely on redesigning the microstructure of the lower prism layer. Although such a composite microstructure can protect the low prism peak by means of structural height difference, the mold processing of the composite microstructure is time-consuming and labor-intensive, which greatly increases the mold manufacturing cost and is not conducive to cost control during mass production.

[0032] Furthermore, the prism base width of the columnar prism structure is ≤20μm, the prism height is ≤5μm, and the top of the prism is arc-shaped. This ensures both a good fit and excellent optical performance.

[0033] Of course, this columnar prism structure can be formed by processes including but not limited to: UV embossing, photolithography, or precision molding.

[0034] Specifically, setting the bottom width of the cylindrical prism to less than or equal to 20 μm ensures that the light has good refraction concentration and directional consistency during the entry and exit processes.

[0035] Setting the height of the cylindrical prism to less than or equal to 5μm ensures the product's thinness.

[0036] Using a rounded curved surface structure at the top of the cylindrical prism can avoid excessive local pressure generated by sharp corners during the pressing process, which could damage its own structure or the surface of the object being bonded. At the same time, it can also facilitate processing and molding. Furthermore, it helps to eliminate stress concentration at sharp corners, prevent film damage or micro-cracks, improve the continuity of light distribution, and reduce moiré patterns, bright spots, and visual glare.

[0037] Furthermore, the base width of the prism is 5μm-20μm, and the height of the prism is 3μm-5μm. This allows for the achievement of optimal optical performance, such as anti-interference and high brightness.

[0038] Furthermore, thanks to the presence of the microstructure bonding layer, light passing through this multi-layered brightening film can achieve an additional light-converging effect, thereby altering the viewing angle. In other words, the uniformity of the spatial viewing angle can be controlled by optimizing the size and extension direction of the microstructure to achieve the desired design effect.

[0039] like Figure 2As shown, a first prism layer 30 is provided on the side of the microstructure bonding layer 20 away from the first substrate layer 10, and the tip of the first prism layer 30 is attached to the microstructure bonding layer 20. The extension direction of the microstructure bonding layer 20 is pre-set at an angle to the extension direction of the first prism layer 30. It is understood that by reserving this angle, a good bonding effect can be achieved, while also ensuring good optical performance.

[0040] Furthermore, the included angle is 30°-90°. It is understood that this allows for a variety of included angles to be selected, thus adapting to the needs of various usage scenarios.

[0041] Specifically, when the included angle is in the range of 30°-60°, the direction of light emission is partially shifted to the lateral direction, which can significantly improve the side-view brightness and is suitable for wide-viewing-angle displays or vehicle information screens. When the included angle is close to 90°, the prism structure is orthogonally arranged, which can enhance the light intensity distribution in the vertical direction and is suitable for high-brightness display systems.

[0042] Furthermore, a second substrate layer 40 is provided on the side of the first prism layer 30 away from the microstructure bonding layer 20; The first substrate layer 10 and the second substrate layer 40 are any one of PMMA, TAC, PET, COP, PP, TPU, or PE. This allows for a variety of materials to be selected, thus enabling flexible use.

[0043] It is important to know that TAC and PET materials have good light transmittance and moisture resistance, making them suitable for general LCD backlight systems; PMMA and COP materials do not have birefringence properties, but their special optical effects are suitable for high-brightness or automotive display applications; TPU and PE have excellent flexibility and impact resistance, enabling flexible display devices that can be bent or rolled up.

[0044] Furthermore, the refractive index of the microstructure bonding layer 20 is 1.35-1.7. It is understood that the gradient distribution of the refractive index has a significant impact on the refraction path of light and interface reflection.

[0045] Specifically, when the refractive index is low (1.35-1.45), the bonding layer can play an optical buffering and anti-reflection role; when the refractive index is in the medium range (1.45-1.6), it can form a strong light focusing ability; when the refractive index is high (1.6-1.7), it enhances the directional deflection effect of light and further improves the optical brightening performance.

[0046] By precisely controlling the refractive index, an optical film can achieve a balance between high brightness and high viewing angle uniformity, while reducing interface reflection loss.

[0047] like Figure 3-5 As shown, a diffusion layer 50 is disposed on the side of the first substrate layer 10 away from the microstructure bonding layer 20 to form an optical film with a DOP structure; or, A microlens structure 60 is disposed on the side of the first substrate layer 10 away from the microstructure bonding layer 20 to form an optical film with an MOP structure; or, A second prism layer 70 is disposed on the side of the first substrate layer 10 away from the microstructure bonding layer 20, and the second prism layer 70 and the extension direction of the first prism layer 30 are preset at an angle to form an optical film with a POP structure. It can be understood that the DOP (Diffusion on Prism sheet) structure involves a diffusion layer 50 disposed on the microstructure bonding layer 20. The diffusion layer 50 is composed of a diffusion medium containing microparticles or microvoids, which can homogenize the backlight emitted light field, eliminate local bright spots, and improve display uniformity.

[0048] MOP (Micro-lens on Prism sheet) structure: A microlens structure layer 60 is set on the microstructure bonding layer 20. The microlens array can diffuse the emitted light while focusing locally, achieving a balance between light focusing and light uniformity, which is suitable for display scenarios with high brightness and high shading.

[0049] POP (Prism on Prism sheet) structure: A second prism layer 70 is stacked on the microstructure bonding layer 20, and the extension directions of the first prism layer 30 and the second prism layer 70 are preset to have an angle. The double prism layer forms a highly directional light output, which is suitable for high-brightness backlight modules and mobile display systems.

[0050] The modular configuration described above allows for flexible combinations of optical film structures, thereby meeting the comprehensive requirements of different applications for brightness, diffusion, and viewing angle distribution.

[0051] Of course, the structure of this application can also be applied to other types of laminated brightening films, and no limitation is made in this application.

[0052] Furthermore, a back coating layer (not shown in the figure) is provided on the side of the second substrate layer 40 away from the first prism layer 30. It can be understood that the back coating layer, as the light-incident surface, mainly functions to receive external light and guide it into the prism layer. The back coating layer is usually made of a material with high light transmittance and good anti-reflection properties to ensure that light can enter the prism layer efficiently.

[0053] Preferably, the haze of the back coating is within the range of 2%-20%. Controlling the haze of the back coating within the range of 2%-20% can effectively reduce scattered light in the backlight module. Appropriate haze settings can improve display effects. Excessive haze may cause image blurring, while excessive haze may affect the uniform distribution of light. Within this range, the back coating can reduce unnecessary scattered light while maintaining uniform light distribution, thereby improving image clarity and detail.

[0054] This application also relates to a display device including the aforementioned bonding film.

[0055] The following examples further illustrate this point: Using the microstructure bonding layer 20 mentioned in this embodiment, a lower brightening layer with a bottom width of 70um is bonded to the prism to make a DOP product; wherein, the upper diffusion layer 50 has a haze of 75% and a 3% haze back coating as an anti-adsorption layer.

[0056] Example 1 The columnar prism of the microstructure bonding layer 20 has a width of 10 μm and a height of 3 μm. The extension direction of the microstructure bonding layer 20 forms an angle of 90° with the extension direction of the first prism layer 30.

[0057] At this point, the test results for the DOP laminated film were as follows: no interference was observed, the brightness ratio was 103.1%, and the half-viewing angle was ±25°.

[0058] Example 2 The difference between Example 2 and Example 1 is that the width of the columnar prism in the microstructure bonding layer 20 is 20 μm.

[0059] At this point, the test results for the DOP lamination film were as follows: the interference behavior was observed to be slight, the brightness ratio was 103.3%, and the half-viewing angle was ±25°.

[0060] Example 3 The difference between Example 3 and Example 1 is that the width of the columnar prism in the microstructure bonding layer 20 is 5 μm.

[0061] At this point, the test results for the DOP laminated film were as follows: no interference was observed, the brightness ratio was 103.4%, and the half-viewing angle was ±24°.

[0062] Example 4 The difference between Example 4 and Example 1 is that the extension direction of the microstructure bonding layer 20 forms an angle of 45° with the extension direction of the first prism layer 30.

[0063] At this point, the test results for the DOP laminated film were as follows: no interference was observed, the brightness ratio was 98.1%, and the half-viewing angle was ±31°.

[0064] Example 5 The difference between Example 5 and Example 1 is that the extension direction of the microstructure bonding layer 20 forms an angle of 30° with the extension direction of the first prism layer 30.

[0065] At this point, the test results for the DOP lamination film were as follows: no interference was observed, the brightness ratio was 96.5%, and the half-viewing angle was ±33°.

[0066] Example 6 The difference between Example 6 and Example 1 is that the height of the cylindrical prism is 5 μm.

[0067] At this point, the test results of the DOP lamination film were as follows: the interference performance was observed to be slight interference, the brightness ratio was 105.1%, and the 1 / 2 viewing angle was ±24°.

[0068] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that a general unstructured full-surface bonding layer is used, and the bonding layer thickness is 3μm.

[0069] At this point, the test results for the DOP lamination film were as follows: the interference behavior was observed to be slight interference, the brightness ratio was 100%, and the 1 / 2 viewing angle was ±23°.

[0070] The results of each embodiment and comparative example are shown in Table 1: Table 1 The test results above show that: 1. As can be seen from Examples 1-3 and Comparative Example 1, when a microstructure bonding layer is present, the brightness is higher than that of a general planar bonding layer product because the peak destruction of the first prism layer 30 (lower prism) is reduced; and when the width of the columnar prism in the microstructure bonding layer is reduced, it helps to resolve the interference phenomenon.

[0071] 2. As can be seen from Examples 4-5 and Comparative Example 1, when the angle between the columnar prism of the microstructure bonding layer 20 and the first prism layer 30 (lower prism) deviates from 90 degrees, the viewing angle can be significantly improved under the condition that the reduction in brightness is controllable.

[0072] 3. As can be seen from Example 6 and Comparative Example 1, when the height of the columnar prism increases, the brightness is further improved.

[0073] This application has the following beneficial effects: 1. Compared with traditional full-surface bonding layers, the microstructure bonding layer of this technology can provide a relatively small bonding contact area, reducing damage to the tip of the microstructure of the underlying brightness enhancement layer and improving brightness. 2. The microstructure bonding layer can adjust the refractive index of the material, and the optical brightness of the overall product can also be further adjusted; 3. The extension direction of the microstructure bonding layer prism and the extension direction of the lower brightness enhancement layer prism can be designed with various angles, which can control the overall product brightness, viewing angle and anti-interference ability.

[0074] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and all such equivalent transformations fall within the protection scope of the present invention.

Claims

1. A bonding adhesive layer structure, characterized in that, include: A first substrate layer (10); and A microstructure bonding layer (20) is arranged in a sequential and orderly array on the first substrate layer (10) along a preset direction; The microstructure bonding layer (20) consists of a plurality of linear columnar prism structures to form a discontinuous bonding surface.

2. The adhesive layer structure according to claim 1, characterized in that, The columnar prism structure has a prism base width of ≤20μm, a prism height of ≤5μm, and a rounded top.

3. The adhesive layer structure according to claim 2, characterized in that, The bottom width of the cylindrical prism is 5μm-20μm, and the height of the prism is 3μm-5μm.

4. The adhesive layer structure according to claim 1, characterized in that, The refractive index of the microstructure bonding layer (20) is 1.35-1.

7.

5. A laminating film, characterized in that, Includes the adhesive layer structure as described in any one of claims 1-4; A first prism layer (30) is provided on the side of the microstructure bonding layer (20) away from the first substrate layer (10), and the tip of the first prism layer (30) is bonded to the microstructure bonding layer (20); The extension direction of the microstructure bonding layer (20) is pre-set to form an angle with the extension direction of the first prism layer (30).

6. The bonding film according to claim 5, characterized in that, The included angle is 30°-90°.

7. The bonding film according to claim 5, characterized in that, A second substrate layer (40) is disposed on the side of the first prism layer (30) away from the microstructure bonding layer (20); Wherein, the first substrate layer (10) and the second substrate layer (40) are any one of PMMA, TAC, PET, COP, PP, TPU or PE.

8. The bonding film according to claim 5, characterized in that, A diffusion layer (50) is disposed on the side of the first substrate layer (10) away from the microstructure bonding layer (20) to form an optical film with a DOP structure; or, A microlens structure (60) is disposed on the side of the first substrate layer (10) away from the microstructure bonding layer (20) to form an optical film with an MOP structure; or, A second prism layer (70) is provided on the side of the first substrate layer (10) away from the microstructure bonding layer (20), and the second prism layer (70) and the extension direction of the first prism layer (30) are preset to form an optical film with a POP structure.

9. The bonding film according to claim 7, characterized in that, The second substrate layer (40) has a back coating on the side away from the first prism layer (30).

10. A display device, characterized in that, Includes the bonding film as described in any one of claims 5-9.

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