Light shielding cover and display screen

Abstract

This invention relates to a light-shielding shield and a display screen. The light-shielding shield includes a shielding layer, a first connecting layer, a shielding layer, and a second connecting layer. The second connecting layer is disposed on the side of the shielding layer facing away from the first connecting layer. The second connecting layer includes a filling portion and conductive particles. Along the height direction of the filling portion, the first filling portion extends from the side closest to the shielding layer to the side furthest away from the shielding layer at a first predetermined distance d1, and the remaining portion is the second filling portion. The density of conductive particles in the first filling portion is greater than the density of conductive particles in the second filling portion, and the distance between the conductive particles in the second filling portion and the side of the second connecting layer furthest from the shielding layer is greater than or equal to 2 μm. This special structure can significantly optimize the overall initial adhesion, thereby solving the defects of traditional conductive cloth solutions such as poor adhesion and easy edge lifting and detachment, which is beneficial to further meeting the assembly and use requirements of screen shielding covers.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic shielding materials technology, and in particular to a light-shielding shield and a display screen. Background Technology

[0002] With the development of display technology, black film technology has emerged to ensure screen display quality. Variations such as black light-blocking tape and black-and-white adhesive are also commonly used. These films are typically made with PET as the base material, coated with high-light-blocking black ink, and then bonded to the screen edges using processes like screen printing and photolithography. As display technology evolves towards thinner and lighter designs and higher screen-to-body ratios, the bezel designs of various screens, including LCD and OLED, are becoming increasingly refined. The shielding effect of the black film around the screen edges has become crucial for ensuring display quality.

[0003] As electronic devices become thinner, lighter, higher-frequency, and more curved, the comprehensive performance requirements for shielding covers are becoming increasingly stringent. This has led to the development of electromagnetic shielding cover technology, which is mainly used for electromagnetic shielding and light protection. Optical shielding can block light leakage from the backlight or edge of the light-emitting layer inside the screen, eliminate halo phenomenon, improve image contrast and display purity, and absorb stray light from the external environment to reduce glare interference and ensure a good viewing experience under different lighting conditions. Conductive black film can also achieve EMI electromagnetic shielding to avoid interference from electronic components, while enhancing edge sealing to prevent dust from entering and ensuring long-term stable operation of the screen. It is one of the indispensable core auxiliary components of modern display devices.

[0004] Traditional technology uses a combination of insulating and conductive fabric layers for screen edging and shielding. However, current conductive fabric solutions are not well-fitting and are prone to detachment, affecting the light-blocking and electromagnetic shielding effects. Summary of the Invention

[0005] Therefore, it is necessary to provide a light-shielding cover and display screen that can effectively improve the stability of the connection with the screen and ensure the light-shielding and electromagnetic shielding effects.

[0006] The technical solution is as follows: A light-shielding shield, comprising: a shielding layer; a first connecting layer disposed on one side of the shielding layer; a shielding layer disposed on one side of the shielding layer opposite to the shielding layer; a second connecting layer disposed on one side of the shielding layer opposite to the first connecting layer, the second connecting layer comprising a filling portion and conductive particles, and along the height direction of the filling portion, starting from one side close to the shielding layer and moving away from one side away from the shielding layer at a first preset distance d1, the remaining portion is the second filling portion, the density of the conductive particles in the first filling portion is greater than the density of the conductive particles in the second filling portion, and the distance between the conductive particles in the second filling portion and the side of the second connecting layer away from the shielding layer is greater than or equal to 2μm.

[0007] In one embodiment, the density of conductive particles in the first filling portion is 15% to 20% higher than the density of conductive particles in the second filling portion.

[0008] In one embodiment, the shortest distance between the conductive particles in the first filling portion and the shielding layer is ≤5μm.

[0009] In one embodiment, the minimum spacing between the conductive particles in the first filling portion is 0.5~5μm.

[0010] In one embodiment, the minimum spacing between the conductive particles in the second filling portion is 0.5~5μm.

[0011] In one embodiment, the initial adhesion of the second bonding layer is ≤7# steel ball, and the holding force is ≥36h.

[0012] In one embodiment, the conductive particles have a particle size of 3~8μm.

[0013] In one embodiment, the ratio of the first preset distance d1 to the thickness of the second connecting layer is 0.2 to 0.5.

[0014] In one embodiment, the ratio of the thickness of the second connecting layer to the thickness of the shielding layer is greater than or equal to 8.

[0015] In one embodiment, the thickness of the second connecting layer is 15~60μm.

[0016] In one embodiment, the light-shielding shield further includes a protective layer disposed on one side of the second connecting layer opposite to the shielding layer.

[0017] A display screen comprising the light-shielding cover described in any one of the above.

[0018] The aforementioned light-shielding shield integrates functions through a multi-layered composite structure consisting of a shielding layer, a first connecting layer, a shielding layer, and a second connecting layer. The second connecting layer is divided into a first filling part and a second filling part. The first filling part, which is closer to the shielding layer, has a higher density of conductive particles, ensuring a stable conductive connection with the shielding layer and ensuring overall conductivity uniformity. The conductive particles in the second filling part are ≥2μm away from the surface, preventing the conductive particles from being exposed and affecting the adhesion performance. At the same time, this special structure of the second connecting layer, together with the first connecting layer, can significantly optimize the initial adhesion of the overall bonding, thereby solving the defects of traditional conductive cloth solutions that are not flat and are prone to curling and detachment. It not only ensures the light-shielding effect of the shielding layer and the electromagnetic shielding effect of the shielding layer, but also achieves a flat fit and no detachment during use, which is conducive to further meeting the assembly and use requirements of screen shielding covers.

[0019] The aforementioned display screen has its optimized light-shielding cover mounted on its edge. The shielding layer provides light leakage protection and stray light absorption at the screen edge, while the shielding layer provides electromagnetic shielding. The second connecting layer achieves a stable fit through optimized structure and parameters. The synergistic effect of each layer ensures the display quality and operational stability of the screen. This solution addresses the issues of poor fit and easy detachment in traditional screen edge shielding solutions, ensuring no light leakage or glare at the screen edge and stable electromagnetic shielding. It also improves the assembly efficiency and long-term reliability of the display screen, adapting to the usage needs of various high screen-to-body ratio and thin and light displays, thereby enhancing product competitiveness. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the light-shielding shield described in one embodiment;

[0023] Figure 2 This is a schematic diagram of the structure of the light-shielding shield described in another embodiment;

[0024] Explanation of reference numerals in the attached figures:

[0025] 100. Light-shielding cover; 110. Shielding layer; 120. First connecting layer; 130. Shielding layer; 140. Second connecting layer; 141. First filling part; 142. Second filling part; 143. Conductive particles; 150. Protective layer. Detailed Implementation

[0026] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0027] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0029] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0030] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0031] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0032] See Figure 1 , Figure 1 A schematic diagram of a light-shielding shield according to an embodiment of the present invention is shown. The light-shielding shield 100 provided in this embodiment includes: a shielding layer 110, a first connecting layer 120, a shielding layer 130, and a second connecting layer 140. The first connecting layer 120 is disposed on one side of the shielding layer 110. The shielding layer 130 has the first connecting layer 120 disposed on the side facing away from the shielding layer 110. The second connecting layer 140 is disposed on the side of the shielding layer 130 facing away from the first connecting layer 120. The second connecting layer 140 includes a filling portion and conductive particles 143. Along the height direction of the filling portion, a first predetermined distance d1 is drawn from the side closest to the shielding layer 130 to the side furthest from the shielding layer 130, forming the first filling portion 141, and the remaining portion forms the second filling portion 142. The density of conductive particles 143 in the first filling portion 141 is greater than the density of conductive particles 143 in the second filling portion 142, and the distance between the conductive particles 143 in the second filling portion 142 and the side of the second connecting layer 140 away from the shielding layer 130 is greater than or equal to 2μm.

[0033] The aforementioned light-shielding shield 100 achieves functional integration through a multi-layer composite structure consisting of a shielding layer 110, a first connecting layer 120, a shielding layer 130, and a second connecting layer 140. The second connecting layer 140 is divided into a first filling portion 141 and a second filling portion 142. The first filling portion 141, which is closer to the shielding layer 130, has a higher density of conductive particles 143, ensuring a stable conductive connection with the shielding layer 130 and ensuring overall conductivity uniformity. The conductive particles 143 in the second filling portion 142 are ≥2μm away from the surface, preventing the conductive particles 143 from being exposed and affecting the adhesion performance. At the same time, the second connecting layer 140 with this special structure, together with the first connecting layer 120, can significantly optimize the overall initial adhesion force, thereby solving the defects of traditional conductive cloth solutions that are not flat and are prone to peeling off. It not only ensures the light-shielding effect of the shielding layer 110 and the electromagnetic shielding effect of the shielding layer 130, but also achieves a close fit and no detachment during use, which is conducive to further meeting the assembly and use requirements of the screen shield 100.

[0034] It should be noted that the first filling portion 141 and the second filling portion 142 are formed by two coating processes. Furthermore, a third filling portion, a fourth filling portion, etc., can be formed by multiple coating processes with different contents of conductive particles 143.

[0035] Optionally, the material of the masking layer 110 includes at least one of polyurethane, epoxy resin, polyimide, PET, PVC, rubber, pigment, and ink.

[0036] Furthermore, an anti-fingerprint layer is also provided on the side of the shielding layer 110 facing away from the first connecting layer 120. This anti-fingerprint layer, through its special surface structure and material properties, forms a hydrophobic and oleophobic surface, reducing the contact area between finger sweat and oil and the surface of the shielding layer 110, thus preventing fingerprint residue from adhering. At the same time, it does not affect the light-blocking performance of the shielding layer 110 and can be firmly bonded to it, without affecting the overall structural integrity and fit stability of the light-shielding cover 100. This effectively prevents fingerprints and stains from being left when fingers touch the edge of the light-shielding cover 100, keeping the product appearance clean and beautiful, reducing the frequency of cleaning, and improving the wear resistance and stain resistance of the shielding layer 110 surface. This prevents the shielding layer 110 from wear and discoloration due to friction and stain erosion, extending the service life of the light-shielding cover 100 and further improving the user experience.

[0037] Optionally, the anti-fingerprint coating material can be: fluorocarbon resin coating (such as PTFE, PVDF), polysiloxane coating, nano-silica composite coating, graphene modified coating, or other coating materials. Specifically, the anti-fingerprint coating is a polysiloxane coating, which is soft in texture, adheres to the surface of the masking layer 110, and provides both fingerprint resistance and a certain degree of scratch resistance. It is moderately priced and suitable for mass production.

[0038] Optionally, the first connecting layer 120 may be made of pressure-sensitive adhesive or thermosetting adhesive. Further, the shielding layer 130 may be made of metal or non-metallic conductive material.

[0039] The conductive particles 143 in the first filling part 141 and the conductive particles 143 in the second filling part 142 can be made of the same or different materials. Optionally, the conductive particles 143 can be made of: silver, copper, nickel, graphite, carbon black, graphene, carbon nanotubes, aluminum, iron, zinc, antimony-doped tin oxide, aluminum-doped zinc oxide, silver-coated copper powder, silver-coated polymer spheres, or other materials.

[0040] In one embodiment, see Figure 1 The density of conductive particles 143 in the first filling portion 141 is 15% to 20% higher than that in the second filling portion 142. This ratio of conductive particles 143 ensures that the first filling portion 141 near the shielding layer 130 has a sufficiently dense concentration of conductive particles 143 to form an efficient and uniform conductive network, guaranteeing the stability of electromagnetic shielding performance. It also avoids the risk of internal stress concentration or interface delamination during bonding or bending due to excessive density differences between the upper and lower layers. This specific range of difference allows the conductive gradient to meet the requirements of conductive uniformity while maintaining the overall structural continuity of the filling material, thus achieving a better balance between initial adhesion, conformability, and conductivity.

[0041] It should be noted that the density of conductive particles 143 in the first filling part 141 is 15% to 20% higher than that in the second filling part 142. This should be understood as the range of (density of conductive particles 143 in the first filling part 141 - density of conductive particles 143 in the second filling part 142) / density of conductive particles 143 in the first filling part 141 being 15% to 20%.

[0042] In one embodiment, the shortest distance between the conductive particles 143 in the first filling portion 141 and the shielding layer 130 is ≤5μm. By adjusting the coating process to ensure that the distance between the conductive particles 143 in the first filling portion 141 and the shielding layer 130 is ≤5μm, it means that the conductive particles 143 can approach or even contact the shielding layer 130 to the maximum extent, thereby significantly shortening the path of electrons from the shielding layer 130 to the conductive particles 143, which is beneficial for reducing contact resistance. In addition, this close-range configuration ensures that the electromagnetic interference signals captured by the shielding layer 130 can be quickly discharged by the conductive particles 143 in the second connecting layer 140, avoiding impedance attenuation caused by excessive distance, thereby improving the overall response speed and effectiveness of electromagnetic shielding.

[0043] In one embodiment, the minimum spacing between the conductive particles 143 in the first filling portion 141 is 0.5~5μm. Further, the minimum spacing between the conductive particles 143 in the second filling portion 142 is 0.5~5μm. This spacing setting means that the particles can form a microscopic arrangement that is both compact and not excessively stacked. This spacing ensures sufficient contact probability between particles to form a three-dimensional conductive path, achieving excellent conductive uniformity; at the same time, the appropriate spacing also provides space for the filling material, thereby maintaining the cohesive strength and flexibility of the adhesive layer, enabling effective current conduction during bonding, and filling the microscopic unevenness of the surface of the bonded object through the flow of the adhesive, thereby enhancing initial adhesion and conformability.

[0044] Furthermore, the minimum spacing of the conductive particles 143 in the second filling portion 142 is the same as that in the first filling portion 141. This ensures that although the particle density of the second filling portion 142 is lower, its particle distribution still has microscopic uniformity, thereby avoiding blind spots where there are no conductive particles 143. This uniform distribution helps ensure that even in areas near the outer surface, the second filling portion 142 can still function as an auxiliary conductive layer in the event of a small amount of conductivity required (such as electrostatic discharge) or when the conductive path of the first filling portion 141 is damaged due to bending. This maintains the redundancy and reliability of conductivity throughout the thickness of the second connecting layer 140.

[0045] In one embodiment, the initial tack of the second connecting layer 140 is ≤7# steel ball, and the holding force is ≥36h. The initial tack of ≤7# steel ball can achieve gentle and sufficient initial adhesion during assembly, which is convenient for positioning and does not overflow adhesive. The holding force ≥36h reflects the long-term anti-peeling and weather-resistant stability of the adhesive layer. In addition, this indicator can directly solve the problems of traditional conductive cloth not fitting well and easy to fall off, so as to achieve both quick bonding without lifting edges and long-term use without detachment, thus meeting the assembly and durability requirements of the screen shielding cover 100.

[0046] Specifically, the adhesive type of the second connecting layer 140 can be acrylic pressure-sensitive adhesive, mixed neoprene rubber adhesive, silicone pressure-sensitive adhesive, polyurethane pressure-sensitive adhesive, or other adhesive types. In this embodiment, a mixed neoprene rubber adhesive is used, which has high initial tack and fast strength build-up. By reasonably combining tackifying resins and additives such as tert-butylphenol formaldehyde resin, the holding power can reach more than 36 hours. At the same time, it has good bonding strength and resistance to media, which is suitable for the bonding requirements of screen edge covering. Moreover, the adhesive layer is soft and more suitable for curved edge covering structures.

[0047] Furthermore, the adhesive types of the first filler portion 141 and the second filler portion can be the same or different.

[0048] In one embodiment, the conductive particles 143 have a particle size of 3~8μm. The 3~8μm particle size is suitable for the thickness and filling ratio of the second connecting layer 140. If the particle size is too small, it will easily agglomerate; if it is too large, it will easily protrude and damage the adhesive surface. This range can achieve uniform dispersion and stable conductivity. The beneficial effects are: it can efficiently form a conductive path to ensure the shielding effect, and it will not protrude from the adhesive surface to affect the flatness, avoiding particles lifting up and causing poor adhesion or curling edges.

[0049] In one embodiment, the ratio of the first preset distance d1 to the thickness of the second connecting layer 140 is 0.2 to 0.5. This ratio range reasonably divides the area size of the first filling part 141 and the second filling part 142, ensuring that the first filling part 141 has enough space to arrange high-density conductive particles 143 to achieve effective electrical conduction with the shielding layer 130, while retaining a sufficient thickness for the second filling part 142 to ensure its adhesion performance. This avoids insufficient adhesion due to the first filling part 141 being too large and squeezing the space of the second filling part 142, or poor conductivity due to the first filling part 141 being too small. This is beneficial for optimizing the structural distribution of the second connecting layer 140, achieving a precise balance between conductivity and adhesion performance, further improving the bonding stability and electromagnetic shielding reliability of the light-shielding shield 100, and adapting to the edge-wrapping requirements of screens with different thicknesses.

[0050] In one embodiment, the ratio of the thickness of the second connecting layer 140 to the thickness of the shielding layer 130 is greater than or equal to 8. Increasing the thickness of the second connecting layer 140 relative to the shielding layer 130 can increase the bonding area and bonding strength of the second connecting layer 140, ensuring that it can firmly adhere to the screen edge. At the same time, sufficient thickness can accommodate the layered distribution of conductive particles 143, avoiding the limited distribution of conductive particles 143 and affecting the uniformity of conductivity due to insufficient thickness, without affecting the electromagnetic shielding function of the shielding layer 130. It can also improve the bonding stability of the second connecting layer 140, effectively solving the pain points of traditional solutions that are not well-fitting and easy to detach. At the same time, it provides space for the reasonable distribution of conductive particles 143, ensuring the uniformity of electromagnetic shielding and ensuring that the light shielding cover 100 is suitable for long-term use.

[0051] Specifically, the thickness of the second connecting layer 140 is 15~60μm. This range balances processing technology and application requirements. When the thickness is less than 15μm, it is difficult to construct an effective density gradient layer, and the initial adhesion and gap-filling ability will decrease significantly, easily leading to detachment. A thickness exceeding 60μm may increase material costs and occupy too much space in miniaturized and thinner screen modules, affecting assembly accuracy. The 15~60μm range can fully accommodate the conductive particles 143 to form a gradient distribution, ensuring the initial adhesion of ≤7# balls and the holding force of ≥36h, while also meeting the design trend of modern thinner displays.

[0052] In one embodiment, see Figure 2The light-shielding shield 100 also includes a protective layer 150, which is disposed on the side of the second connecting layer 140 facing away from the shielding layer 130. The protective layer 150 covers the adhesive surface of the second connecting layer 140. During the storage, transportation and assembly of the light-shielding shield 100, it can isolate dust, moisture, oil and other impurities, preventing impurities from adhering to the surface of the second connecting layer 140 and affecting its adhesive performance. At the same time, it can prevent the second connecting layer 140 from being scratched or worn, protecting its internal filling part and conductive particles 143 from damage. It can be easily removed during assembly without affecting the adhesion between the second connecting layer 140 and the screen edge. Moreover, the material of the protective layer 150 is adapted to the second connecting layer 140, and there is no adhesive residue after removal, without damaging the structural integrity of the second connecting layer 140. This helps extend the shelf life of the light-shielding cover 100, prevents the second connecting layer 140 from becoming less adhesive and its conductivity from being damaged due to external impurities or physical scratches, ensures that the second connecting layer 140 can maintain its optimal adhesive state during assembly, further guarantees the fit and firmness of the fit, and reduces the assembly defect rate; at the same time, it avoids the residual adhesive residue after removing the protective layer 150 from affecting the screen appearance and use, reduces subsequent cleaning costs, adapts to the needs of mass production and large-scale assembly, and further improves the reliability and practicality of the product.

[0053] Optionally, the protective layer 150 can be made of polyethylene terephthalate (PET) release film, polyethylene (PE) release film, polypropylene (PP) release film, fluorinated release film, or other film materials. Specifically, in this embodiment, the protective layer 150 is made of fluorinated release film, with a fluorinated surface treatment, resulting in extremely low release force, smoother removal, and strong chemical resistance, preventing chemical reaction with the adhesive layer of the second connecting layer 140. It also offers excellent anti-fouling and waterproofing properties, making it suitable for high-end screen scenarios with high requirements for the protective layer 150.

[0054] In one embodiment, the present invention also provides a display screen, the display screen including the light-shielding shield 100 of any of the above.

[0055] The aforementioned display screen has the optimized light-shielding cover 100 assembled on its edge. The shielding layer 110 achieves light leakage shielding and stray light absorption at the screen edge, the shielding layer 130 achieves electromagnetic shielding, and the second connecting layer 140 achieves a stable fit through optimized structure and parameters. The synergistic effect of each layer ensures the display quality and stability of the display screen. This solves the problems of non-fitting and easy detachment of traditional display screen edge shielding solutions, ensuring no light leakage or glare at the display edge, stable electromagnetic shielding effect, and improving the assembly efficiency and long-term reliability of the display screen. It is suitable for the use needs of various high screen ratio and thin and light display screens, and enhances product competitiveness.

[0056] The present invention will be further described in detail below with reference to embodiments and comparative examples. The following embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0057] Example 1

[0058] A light-shielding shield includes a stacked shielding layer, a first connecting layer, a shielding layer, and a second connecting layer. The second connecting layer is 30 μm thick. The filling portion is made of acrylic pressure-sensitive adhesive. The first filling portion is 10 μm thick, and the remaining 20 μm is the second filling portion. The density of conductive particles (silver powder) in the first filling portion is 1.2 × 10⁻⁶. 5 The density of conductive particles in the second filling section is 0.8 × 10⁻⁶ per mm³. 5 The distance between the conductive particles in the second filling section and the side of the second connecting layer away from the shielding layer is 3 μm.

[0059] Test data: Fit and conformity (no lifting, no bubbles) 92%; detachment rate after 72 hours of use 3%; electromagnetic shielding effectiveness at 3GHz frequency 72dB; light blocking rate 98.5%.

[0060] Example 2

[0061] Based on Example 1, the density of conductive particles was adjusted: the density of conductive particles in the first filling part was 1.2 × 10⁻⁶. 5 The density of conductive particles in the second filling section is 1.0 × 10⁻⁶ per mm³. 5 The number of pieces per mm³ is the same as in Example 1; the other parameters are the same.

[0062] Test data: Fit and conformity 94%; detachment rate after 72 hours of use 2.2%; electromagnetic shielding effectiveness 74dB; light blocking rate 98.6%.

[0063] Example 3

[0064] Based on Example 1, the shortest distance between the conductive particles in the first filling part and the shielding layer was adjusted to 4μm; the remaining parameters were the same as in Example 1.

[0065] Test data: Fit and conformity 93%; detachment rate after 72 hours of use 2.8%; electromagnetic shielding effectiveness 77dB; light blocking rate 98.5%.

[0066] Example 4

[0067] Based on Example 1, the spacing between conductive particles was adjusted: the minimum spacing between conductive particles in the first filling part was 2 μm, and the minimum spacing between conductive particles in the second filling part was 3 μm; the remaining parameters were the same as in Example 1.

[0068] Test data: Fit and conformity 93.5%; detachment rate after 72 hours of use 2.5%; electromagnetic shielding effectiveness 75dB; light blocking rate 98.5%.

[0069] Example 5

[0070] Based on Example 1, the adhesive type of the second bonding layer was adjusted to acrylic pressure-sensitive adhesive, and the initial tack was controlled to be 6# steel ball, and the holding force was controlled to be 40h; the remaining parameters were the same as in Example 1.

[0071] Test data: Fit and conformity 95%; detachment rate after 72 hours of use 1.5%; electromagnetic shielding effectiveness 73dB; light blocking rate 98.5%.

[0072] Example 6

[0073] Based on Example 1, the particle size of the conductive particles was adjusted to 5 μm; the remaining parameters were the same as in Example 1.

[0074] Test data: Fit and conformity 93.2%; detachment rate after 72 hours of use 2.6%; electromagnetic shielding effectiveness 76dB; light blocking rate 98.5%.

[0075] Example 7

[0076] Based on Example 1, the thickness of the first filling part was adjusted to 9 μm, the thickness of the second connecting layer was 30 μm, and the ratio of d1 to the thickness of the second connecting layer was 0.3; the remaining parameters were the same as in Example 1.

[0077] Test data: Fit and conformity 93.8%; detachment rate after 72 hours of use 2.3%; electromagnetic shielding effectiveness 74.5dB; light blocking rate 98.6%.

[0078] Example 8

[0079] Based on Example 1, the thickness of the second connecting layer was adjusted to 40 μm, the thickness of the shielding layer to 5 μm, and the ratio of the two was 8; the remaining parameters were the same as in Example 1.

[0080] Test data: Fit and conformity 94.2%; detachment rate after 72 hours of use 2.0%; electromagnetic shielding effectiveness 73.5dB; light blocking rate 98.5%.

[0081] Example 9

[0082] Based on Example 1, the thickness of the second connecting layer was adjusted to 20 μm, and a protective layer, a PET release film with a thickness of 12 μm, was added and placed on the side of the second connecting layer facing away from the shielding layer, satisfying claim 9; the remaining parameters are the same as in Example 1.

[0083] Test data: Fit and conformity 96%; detachment rate after 72 hours of use 1.0%; electromagnetic shielding effectiveness 72.5dB; light blocking rate 98.5%.

[0084] Example 10

[0085] Structural parameters: The second connecting layer is 40 μm thick, the first filling layer is 12 μm thick, and the ratio of the thickness of the second connecting layer to the shielding layer is 8; the conductive particle density of the first filling layer is 1.2 × 10⁻⁶. 5 Units / mm³, second filling part 1.0×10 5 Particles / mm³; the shortest distance between the conductive particles in the first filling part and the shielding layer is 4μm, and the minimum spacing is 2μm; the minimum spacing between the conductive particles in the second filling part is 3μm, and the distance between them and the surface of the second connecting layer is 3μm; the particle size of the conductive particles is 5μm; the initial adhesion of the second connecting layer is 6# steel ball, and the holding force is 40h; a PET release film protective layer is added.

[0086] Test data: Fit and conformity 99%; detachment rate after 72 hours of use 0.1%; electromagnetic shielding effectiveness 80dB; light blocking rate 98.8%.

[0087] Comparative Example 1

[0088] Structural parameters: consistent with Example 1, only the conductive particle density is adjusted; the conductive particle density of both the first and second filling portions is 1.0 × 10⁻⁶. 5 The number of pieces per mm³ is the same as in Example 1; the other parameters are the same.

[0089] Test data: Fit and conformity 75%; detachment rate after 72 hours of use 18%; electromagnetic shielding effectiveness 45dB; light blocking rate 98.4%.

[0090] Comparative Example 2

[0091] Structural parameters: consistent with Example 1, except that the distance between the conductive particles in the second filling part and the surface of the second connecting layer is adjusted to 1 μm; the other parameters are consistent with Example 1.

[0092] Test data: Fit and conformity 80%; detachment rate after 72 hours of use 15%; electromagnetic shielding effectiveness 50dB; light blocking rate 98.5%.

[0093] Comparative Example 3

[0094] Structural parameters: Same as in Example 2, only the density of conductive particles was adjusted; the first filling part is 1.2 × 10⁻⁶. 5 Units / mm³, second filling part 0.9×10 5 The number of pieces per mm³ is the same as in Example 2; the other parameters are the same.

[0095] Test data: Fit and conformity 88%; detachment rate after 72 hours of use 8%; electromagnetic shielding effectiveness 58dB; light blocking rate 98.6%.

[0096] Comparative Example 4

[0097] Structural parameters: consistent with Example 3, except that the shortest distance between the conductive particles in the first filling part and the shielding layer is adjusted to 6μm; the remaining parameters are consistent with Example 3.

[0098] Test data: Fit and conformity 92%; detachment rate after 72 hours of use 3.0%; electromagnetic shielding effectiveness 55dB; light blocking rate 98.5%.

[0099] Comparative Example 5

[0100] Structural parameters: consistent with Example 5, except that the initial adhesion of the second connecting layer is adjusted to 8# steel ball and the holding force is adjusted to 30h; the remaining parameters are consistent with Example 5.

[0101] Test data: Fit and conformity 82%; detachment rate after 72 hours of use 12%; electromagnetic shielding effectiveness 60dB; light blocking rate 98.5%.

[0102] Comparative Example 6

[0103] Structural parameters: Same as in Example 9, except that the thickness of the second connecting layer is adjusted to 10 μm and no protective layer is provided; the remaining parameters are the same as in Example 9.

[0104] Test data: Fit and conformity 85%; detachment rate after 72 hours of use 10%; electromagnetic shielding effectiveness 57dB; light blocking rate 98.5%.

[0105] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A light-shielding cover, characterized in that, The light-shielding shield includes: Shielding layer; A first connecting layer is disposed on one side of the shielding layer; A shielding layer, wherein the shielding layer is provided with a side of the first connecting layer facing away from the shielding layer; The second connecting layer is disposed on the side of the shielding layer facing away from the first connecting layer. The second connecting layer includes a filling portion and conductive particles. Along the height direction of the filling portion, the first filling portion is a first preset distance d1 from the side closest to the shielding layer to the side away from the shielding layer, and the remaining portion is the second filling portion. The density of the conductive particles in the first filling portion is greater than the density of the conductive particles in the second filling portion, and the distance between the conductive particles in the second filling portion and the side of the second connecting layer away from the shielding layer is greater than or equal to 2 μm.

2. The light-shielding cover according to claim 1, characterized in that, The density of conductive particles in the first filling part is 15% to 20% higher than that in the second filling part.

3. The light-shielding cover according to claim 1, characterized in that, The shortest distance between the conductive particles in the first filling portion and the shielding layer is ≤5μm.

4. The light-shielding cover according to claim 1, characterized in that, The minimum spacing between the conductive particles in the first filling portion is 0.5~5μm; and / or, The minimum spacing between the conductive particles in the second filling part is 0.5~5μm.

5. The light-shielding cover according to claim 1, characterized in that, The initial adhesion of the second bonding layer is ≤ 7# steel ball, and the holding force is ≥ 36h.

6. The light-shielding cover according to claim 1, characterized in that, The conductive particles have a particle size of 3~8μm.

7. The light-shielding cover according to claim 1, characterized in that, The ratio of the first preset distance d1 to the thickness of the second connecting layer is 0.2 to 0.

5.

8. The light-shielding cover according to claim 1, characterized in that, The ratio of the thickness of the second connecting layer to the thickness of the shielding layer is greater than or equal to 8.

9. The light-shielding cover according to claim 1, characterized in that, The thickness of the second connecting layer is 15~60μm; and / or, The light-shielding shield also includes a protective layer, which is disposed on the side of the second connecting layer facing away from the shielding layer.

10. A display screen, characterized in that, The display screen includes a light-shielding cover as described in any one of claims 1-9.

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