Anti-reflection transparent electromagnetic shielding film

Abstract

The invention relates to the field of transparent electromagnetic shielding, and discloses an anti-reflection transparent electromagnetic shielding film which is composed of a transparent base film and a metal mesh arranged on the surface of the transparent base film. The metal mesh is composed of intersected metal wires, and the cross section of each metal wire is triangular; a tackifying layer is arranged between the metal mesh and the transparent base film, and a covering layer is arranged on the top of the metal mesh. Compared with the prior art, the metal mesh electromagnetic shielding film has the advantage that the problem that an existing metal mesh electromagnetic shielding film cannot have high transmittance while having high shielding effect is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of transparent electromagnetic shielding, and specifically refers to an antireflective and antireflection transparent electromagnetic shielding film. Background Art

[0002] The electromagnetic shielding film is a thin film material with dual military and civilian attributes, which plays an electromagnetic protection role for electronic circuits and other sensitive devices. At key window positions such as airplanes, automobiles, and ships, a transparent electromagnetic shielding film is required for corresponding protection. Common electromagnetic shielding films include ITO films and metal mesh films. Among them, the ITO film is prepared by sputtering indium tin oxide on the surface of a substrate, and usually can achieve a transmittance of more than 88%. However, the disadvantage of the ITO film is that its resistance is generally high, such as above 10 Ω, and the shielding efficiency in the mid-low frequency band is lower than 40 dB, which restricts its effectiveness in a complex electromagnetic environment. In contrast, the metal mesh film has very obvious advantages in terms of low resistance, such as less than 0.5 Ω, so its shielding efficiency in the full frequency band is relatively excellent, up to 60 dB at most. However, the cross-sectional morphology of the traditional metal mesh is rectangular or trapezoidal, and the top of the cross-section is flat, which has a strong reflection effect on light, and the attenuation of the transmittance generally reaches 20% - 30%, seriously affecting the line of sight of the human eye and posing a major hidden danger for driving. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the above technical difficulties and provide an antireflective and antireflection transparent electromagnetic shielding film, which solves the problem that the existing metal mesh electromagnetic shielding film cannot have both high shielding efficiency and high transmittance.

[0004] To solve the above technical problem, the technical solution provided by the present invention is: an antireflective and antireflection transparent electromagnetic shielding film, which is composed of a transparent base film and a metal mesh arranged on the surface; the metal mesh is composed of intersecting metal wires, and the cross-section of the metal wire is triangular; there is an adhesion layer between the metal mesh and the transparent base film, and there is a covering layer on the top of the metal mesh.

[0005] As an improvement, the metal wire is composed of one of silver, copper, nickel, iron, aluminum, stainless steel metal or a metal alloy composed of the above metals.

[0006] As an improvement, the metal mesh is composed of a polygon such as a circle, a square, a rhombus, or a wave shape.

[0007] As an improvement, the surface of the metal or metal alloy of the metal mesh is covered with a metal oxide or sulfide.

[0008] As an improvement, the triangular cross-section of the metal wire includes a first side and a second side other than the bottom side in contact with the transparent base film, and the angles between the first side and the second side and the bottom side are adjustable.

[0009] As an improvement, the transparent base film is composed of one or more of PET, glass, and PU transparent materials.

[0010] As an improvement, the width of the bottom surface of the triangular cross-section of the metal wire is 0.1 μm - 100 μm.

[0011] As an improvement, the cross-section of the metal mesh grid can be a parallel connection of multiple groups of triangles, and the triangular cross-sections can overlap.

[0012] The advantages of the present invention compared with the prior art are as follows:

[0013] (1) By changing the cross-section of the metal mesh grid to a triangular structure, the light reflection at the top of the cross-section is suppressed. By adjusting the angles of the first side and the second side of the triangle with respect to the bottom side respectively, the reflection angle of light on the side is changed, and the reflected light becomes transmitted light to penetrate the mesh grid, further improving the transmittance.

[0014] (2) A protective layer and a covering layer are provided at the top of the triangular cross-section, which can effectively prevent the problem of corrosion failure of the traditional metal mesh grid electromagnetic shielding film in a complex environment. Description of the Drawings

[0015] Figure 1 is a schematic structural diagram of an antireflection and electromagnetic shielding film of the present invention.

[0016] Figure 2 is a schematic diagram of the shape of the metal mesh grid of the antireflection and electromagnetic shielding film of the present invention.

[0017] Figure 3 is a schematic diagram of the triangular cross-section structure of the antireflection and electromagnetic shielding film of the present invention.

[0018] As shown in the figure: 11, substrate; 12, tackifying; 13, metal mesh grid; 14, protective layer; 15, covering layer; 21, bottom side; 22, first side; 23, second side. Detailed Embodiments

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0020] The present invention provides an antireflection and electromagnetic shielding film, and its structural schematic diagram is as Figure 1 shown. A metal mesh grid 13 is provided on a substrate 11, and the metal mesh grid is composed of intersecting metal wires, as Figure 2The shape of the metal mesh grid shown can be circular, square, diamond-shaped, or wavy. To achieve a transmittance of over 90%, the aperture of the general mesh grid needs to be set to 200 μm or more. Between the metal mesh grid 13 and the transparent base film 11, an adhesion-promoting layer 12 is provided as needed. The purpose of the adhesion-promoting layer 12 is to effectively improve the adhesion of the metal mesh grid to the transparent substrate, meet the reliability requirements for long-term use, and prevent problems such as peeling, cracking, and falling off. Generally, the adhesion achieved after using the adhesion-promoting layer is greater than 2.74 N / cm 2 , for example, when manufacturing a metal mesh grid on a glass substrate by sputtering, since the sputtered metal layer and glass naturally have good adhesion, the adhesion-promoting layer 12 can be omitted. A protective layer 14 is provided on the surface of the metal mesh grid 13 to play a role in corrosion resistance during long-term use under complex conditions. Generally, the materials selected can be metal oxides or sulfides, which are achieved by directly performing relevant chemical reactions on the surface of the completed metal mesh grid 12. An overcoat layer 15 can be provided on the upper part of the adhesion-promoting layer 12 and the protective layer 14 as needed. The overcoat layer 15 is generally an optical resin glue with a refractive index matching that of the transparent substrate, such as acrylic resin glue, epoxy resin glue, phenolic resin glue, etc.

[0021] The selection range of the refractive index is generally 1.5 - 1.9, and the thickness is generally 5 - 10 μm.

[0022] The cross-section of the metal wire of the metal mesh grid 12 is triangular, and the triangle is composed of a bottom side 21, a first side 22, and a second side 23. Among them, the width of the bottom side 21 is preferably 5 μm. The angle θ1 between the first side 22 and the bottom side needs to be greater than 45°, and the angle θ2 between the second side 23 and the bottom side needs to be greater than 45°. θ1 and θ2 can be unequal, and the antireflection effect of each angle can be independently controlled. By setting in this way, all the reflected light generated by the light incident perpendicular to the transparent substrate on the first side and the second side will completely penetrate the mesh grid and be converted into transmitted light. At the same time, the triangular cross-section reduces the top side of the traditional trapezoidal or rectangular cross-section, so all the reflections caused by the top side are suppressed. Generally speaking, for a traditional metal mesh grid transparent electromagnetic shielding film with a transmittance of 80%, the metal mesh grid itself can cause 13% of reflection. However, by implementing this method, an antireflection of over 10% can be achieved, and the total transmittance of the transparent electromagnetic shielding film can reach 89.2%.

[0023] In summary, the present invention changes the cross-section of the metal mesh grid to a triangular structure, suppressing the light reflection at the top of the cross-section. By adjusting the angles of the first side and the second side of the triangle with respect to the bottom side respectively, the reflection angle of the light on the side is changed, and the reflected light becomes transmitted light that penetrates the mesh grid, further improving the transmittance. A protective layer and an overcoat layer are provided at the top of the triangular cross-section, which can effectively prevent the problem of corrosion failure of the traditional metal mesh grid electromagnetic shielding film in a complex environment.

[0024] It should be understood that the application of the present invention is not limited to the above examples. For those of ordinary skill in the art, improvements or changes can be made according to the above description, and all such improvements and changes shall fall within the protection scope of the appended claims of the present invention.

[0025] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0026] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

[0027] The above describes the present invention and its implementation manners. Such description is not restrictive. What is shown in the drawings is only one of the implementation manners of the present invention, and the actual structure is not limited thereto. Generally speaking, if those of ordinary skill in the art are inspired by it and design similar structural manners and embodiments without creative efforts without departing from the purpose of the present invention, they shall fall within the protection scope of the present invention.

Claims

1. A transparent electromagnetic shielding film with enhanced light transmission and reduced reflection, characterized in that: It is composed of a transparent base film and a metal mesh grid provided on the surface; The metal mesh grid is composed of intersecting metal wires, and the cross-section of the metal wire is triangular; there is an adhesion-promoting layer between the metal mesh grid and the transparent base film, and there is a covering layer on the top of the metal mesh grid.

2. The antireflection and electromagnetic shielding transparent film according to claim 1, wherein: The metal wire is composed of one of silver, copper, nickel, iron, aluminum, stainless steel metal or a metal alloy composed of the above metals.

3. The anti-reflection and electromagnetic shielding transparent film according to claim 1, wherein: The metal mesh grid is composed of one of polygons such as circular, square, diamond, and wavy.

4. The antireflection and electromagnetic shielding transparent film according to claim 3, wherein: The surface of the metal or metal alloy of the metal mesh grid is covered with metal oxide or sulfide.

5. The antireflection and electromagnetic shielding transparent film according to claim 1, characterized in that: The triangular cross-section of the metal wire includes a first side and a second side other than the bottom side in contact with the transparent base film, and the angles between the first side and the second side and the bottom side are adjustable.

6. The antireflection and electromagnetic shielding transparent film according to claim 1, characterized in that: The transparent base film is composed of one or more of PET, glass, and PU transparent materials.

7. The antireflection and electromagnetic shielding transparent film according to claim 5, wherein: The width of the bottom surface of the triangular cross-section of the metal wire is 0.1μm - 100μm.

8. The antireflection and electromagnetic shielding transparent film according to claim 1, wherein: The cross-section of the metal mesh grid can be multiple groups of triangles in parallel, and the triangular cross-sections can overlap.

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