High-transparency electromagnetic shielding glass and preparation method thereof

Abstract

The invention discloses high-transparency electromagnetic shielding glass and a preparation method thereof. The electromagnetic shielding glass comprises high-transparency glass, a pre-coating layer, a conductive layer and a protective layer which are sequentially arranged, the pre-coating layer is formed by coating and curing a pre-coating layer resin solution containing TiO2 coated SiO2 core-shell particles; the conductive layer is composed of a magnetic field orientation silver wire layer and a silver nanosheet gap filling layer, and the preparation process of the magnetic field orientation silver wire layer comprises the steps that a pre-coating layer is coated with silver nanowire ink, then a pulsed magnetic field is applied in the direction perpendicular to the high-transparency glass, and then infrared drying, laser scanning and external field auxiliary reduction are conducted to prepare the magnetic field orientation silver wire layer; and the silver nanosheet gap filling layer is formed by coating silver nanosheet slurry. According to the electromagnetic shielding glass, through the composite structure design of the high-transparency glass, the pre-coating layer, the conductive layer and the protective layer, the optimal balance of optical transparency and electromagnetic shielding effectiveness is synergistically realized, meanwhile, the structural stability and the large-scale preparation feasibility are considered, and the performance limitation of a traditional material is broken through on the whole.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic shielding materials, and in particular to a highly transparent electromagnetic shielding glass and a preparation method thereof. Background Art

[0002] With the rapid development and widespread application of modern electronic detection, guidance, and electromagnetic interference technologies, the electromagnetic environment in the military field is becoming increasingly complex. Electromagnetic spectrum management and protection have become crucial core capabilities. Competition among countries in the development of electromagnetic shielding materials and equipment protection technologies is intensifying. The demand for high-performance, multifunctional electromagnetic shielding materials is particularly urgent in the protection of core applications such as command, communications, and critical platforms. Window protection systems for specialized vehicles (such as command vehicles and electronic reconnaissance vehicles) face significant technical challenges: They must effectively shield intrusive electromagnetic interference (EMI) and detection signals within specific operating frequency bands (e.g., 1-18 GHz) to ensure the safe and stable operation of precision electronic equipment and communication links within the vehicle. Furthermore, they must maintain extremely high visible light transmittance (typically >80%) to ensure clear, expansive vision and situational awareness for personnel. This demanding dual requirement of both high transparency and strong electromagnetic shielding effectiveness makes it difficult for traditional window materials to meet these requirements, creating a critical technical bottleneck in the current high-value platform protection sector.

[0003] Currently widely used transparent shielding materials, such as indium tin oxide (ITO)-coated glass, while popular in civilian displays, face significant limitations in high-performance military applications. The main issues are: 1) Performance bottlenecks: The inherent material properties limit further improvements in conductivity. To achieve adequate electromagnetic shielding effectiveness, the coating thickness must be increased, resulting in reduced light transmittance and a limited shielding bandwidth. 2) Process and cost: The ITO coating process typically requires a high-temperature vacuum environment (such as magnetron sputtering). This involves expensive equipment, complex processes, and difficulty in controlling yield, resulting in high costs and hindering large-scale deployment and maintenance. 3) Mechanical and chemical stability: ITO films are relatively brittle and prone to performance degradation or damage in complex and harsh application environments (such as vibration, dust, and corrosion). Therefore, developing a transparent electromagnetic shielding material with ultra-high visible light transmittance (>85%), excellent electromagnetic shielding performance (square resistance ≤15Ω, SE ≥25dB ​​@ 1-18GHz), good environmental adaptability and mass production feasibility has become one of the core research directions to promote the upgrade of next-generation key platform protection technology, with great strategic value and broad application prospects. Summary of the Invention

[0004] To address the aforementioned technical issues, the present invention aims to provide a highly transparent electromagnetic shielding glass and a method for its preparation. This electromagnetic shielding glass, through its composite structural design consisting of a highly transparent glass substrate, a functional pre-coating layer, an oriented conductive layer with controllable magnetic field construction, and a protective layer, achieves an optimal balance between optical transparency and electromagnetic shielding effectiveness while also balancing structural stability and scalable fabrication feasibility, ultimately overcoming the performance limitations of traditional materials.

[0005] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions: On one hand, the present invention provides a high-transparency electromagnetic shielding glass, which includes high-transparency glass, a pre-coating layer, a conductive layer and a protective layer designed in sequence from top to bottom; the pre-coating layer is formed by coating and curing a pre-coating resin solution containing TiO2@SiO2 core-shell particles; the conductive layer is composed of a magnetic field-oriented silver wire layer and a silver nanosheet filling layer, wherein the preparation process of the magnetic field-oriented silver wire layer is: coating nano silver wire ink on the pre-coating layer, then applying a pulsed magnetic field in a direction perpendicular to the high-transparency glass, and then performing infrared drying, laser scanning and external field-assisted reduction; the silver nanosheet filling layer is formed by coating with silver nanosheet slurry.

[0006] Preferably, the high-transparency glass is explosion-proof glass or high-silicon glass.

[0007] Furthermore, the pre-coating resin solution comprises the following components by mass percentage: 60-70% resin matrix, 10-15% TiO2@SiO2 core-shell particles, 2-5% photoinitiator, 0.2-1% additive, and 15-20% solvent. The additive is at least one of a leveling agent, a defoaming agent, an adhesion promoter, and a dispersant.

[0008] Further preferably, the resin matrix in the pre-coating resin solution is selected from at least one of acrylic resin, polyurethane acrylic resin, epoxy acrylic resin, and amino acrylic resin.

[0009] Furthermore, the nano silver wire ink includes the following components in percentage by mass: 0.6% to 50% nano silver wire dispersion, 0.5% to 5.0% alcohol additive, 0.05% to 0.1% ultraviolet absorber, 0.01% to 0.1% dispersing additive, 0.01% to 0.5% film-forming additive, and the balance is deionized water; wherein the solid content of the nano silver wire is 0.1% to 5%.

[0010] Furthermore, the silver nanosheet slurry comprises the following components in percentage by mass: 1-3% silver nanosheets, 0.5-2% dispersant, 0.1-0.5% orientation control agent, 0-0.3% functional additive, and the balance being dispersion medium; the orientation control agent is a cationic surfactant or a zwitterionic surfactant.

[0011] Furthermore, the protective layer is formed by coating and curing a protective layer resin solution, wherein the protective layer resin solution comprises the following components by weight: 45-65% resin matrix, 5-8% curing agent, 0.2-2% additive, and 20-45% solvent. The resin matrix is ​​selected from at least one of acrylic resin, polyurethane acrylic resin, epoxy acrylic resin, and amino acrylic resin; and the additive is selected from at least one of a leveling agent, a defoaming agent, a UV absorber, and a wetting agent.

[0012] Another aspect of the present invention provides a method for preparing highly transparent electromagnetic shielding glass, comprising the following steps: (1) Substrate treatment Highly transparent glass was selected as the substrate and sequentially subjected to alkali washing, acid washing, deionized water rinsing and nitrogen drying; (2) Pre-coating coating and curing Preparing a pre-coating resin solution, applying the pre-coating resin solution on the high-transparency glass, and preheating and curing to form a pre-coating layer; (3) Preparation of magnetic field oriented silver wire layer Prepare nano silver wire ink, apply the nano silver wire ink to the pre-coating layer, apply a pulsed magnetic field perpendicular to the substrate to align the nano silver wires, and then perform infrared drying, laser scanning, and external field-assisted reduction to obtain a magnetic field-oriented silver wire layer; (4) Construction of silver nanosheet filling layer preparing a silver nanosheet slurry, coating the silver nanosheet slurry on the magnetic field-oriented silver wire layer, and then drying the silver nanosheet gap-filling layer; (5) Protective layer coating and curing A protective layer resin solution is prepared, coated on the silver nanosheet interstitial layer, and cured to form a protective layer.

[0013] Furthermore, in step (3), the intensity of the pulsed magnetic field is 0.5-1.5 T, and the frequency is 10-12 Hz.

[0014] Furthermore, in step (3), the temperature of the infrared drying is 80-100° C., the wavelength of the laser scanning is 800-850 nm, and the external field-assisted reduction is plasma-assisted reduction or ultraviolet photocatalytic reduction.

[0015] The technical effects of the present invention are: (1) The present invention fundamentally solves the contradiction between optical transmittance and electromagnetic shielding effectiveness in traditional transparent shielding materials through its unique four-layer composite structure design. While ensuring that the visible light transmittance is significantly higher than 85% (meeting the high perspective requirements of special vehicles), its conductive layer design (magnetic field oriented silver wire layer + silver nanosheet filling layer) works synergistically to achieve extremely low sheet resistance, thereby providing excellent electromagnetic shielding effectiveness and effectively defending against intrusive electromagnetic interference and detection signals.

[0016] (2) The pre-coating layer in the present invention not only serves as an attachment base for the subsequent conductive layer, but the TiO2@SiO2 core-shell particles it contains also play a key role: on the one hand, the TiO2@SiO2 core-shell particles form a refractive index gradient transition layer in the resin matrix: the high-refractive TiO2 core matches the highly transparent glass substrate, and the low-refractive SiO2 shell is close to the pre-coating resin, eliminating the Fresnel reflection loss at the traditional glass-resin interface and effectively improving the overall visible light transmittance; on the other hand, the core-shell particles can also construct a micro-nano structure to produce a wide-spectrum anti-reflection property, thereby reducing the full-band reflectivity of the glass substrate side and significantly improving the effective light transmittance.

[0017] (3) During the preparation of the magnetic field-oriented silver wire layer in the present invention, a pulsed magnetic field is applied perpendicular to the glass, forcing the nanosilver wires to precisely align along the normal direction. This regular perpendicular orientation significantly improves the conduction efficiency and axial conductivity of the silver wire network, achieving low square resistance with a silver wire dosage far lower than the coverage of traditional disordered networks. Furthermore, through the synergistic effects of infrared drying, laser scanning, and external field reduction, the physical shaping, defect repair, and intrinsic performance enhancement of the conductive network are simultaneously achieved under low-temperature, non-destructive conditions, significantly improving the conductive efficiency of the silver wires.

[0018] (4) The present invention constructs a silver nanosheet interstitial layer on top of the magnetic field-oriented silver wire layer. The two-dimensional flaky silver fills the tiny gaps between the vertical silver wire network, significantly reducing the contact resistance at the overlap points between the silver wires and forming a denser, more uniform, three-dimensional interpenetrating, and highly efficient conductive network. This significantly improves the uniformity of the in-plane current distribution and current carrying capacity, and in conjunction with the magnetic field-oriented silver wire layer, achieves lower square resistance and superior shielding effectiveness.

[0019] (5) The outermost protective layer in the present invention provides a solid physical barrier for the entire composite structure, effectively resisting mechanical wear, chemical corrosion and moisture erosion, etc., ensuring the long-term stability of the conductive layer (in complex and harsh environments) and the durability of the electromagnetic shielding effectiveness, greatly improving the reliability of the product in practical applications.

[0020] (6) The highly transparent electromagnetic shielding glass of the present invention adopts coating, magnetic field assisted orientation, laser treatment and other processes, has good compatibility and controllability, and can achieve large-scale stable manufacturing.

[0021] The present invention achieves an optimal balance between optical transparency and electromagnetic shielding effectiveness through a composite structural design of a highly transparent glass substrate, a functional pre-coating layer, an oriented conductive layer constructed with controllable magnetic field, and a protective layer, while taking into account structural stability and feasibility of large-scale preparation, thus breaking through the performance limitations of traditional materials as a whole. DETAILED DESCRIPTION

[0022] The technical solutions of the present invention are described clearly and completely below with reference to specific embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0023] The present invention provides a high-transparency electromagnetic shielding glass, which comprises high-transparency glass, a pre-coating layer, a conductive layer and a protective layer designed in sequence from top to bottom; wherein the pre-coating layer is formed by coating and curing a pre-coating resin solution containing TiO2@SiO2 core-shell particles; the conductive layer is composed of a magnetic field-oriented silver wire layer and a silver nanosheet interstitial layer; wherein the magnetic field-oriented silver wire layer is prepared by coating nano silver wire ink on the pre-coating layer, then applying a pulsed magnetic field in a direction perpendicular to the high-transparency glass, and then performing infrared drying, laser scanning and external field-assisted reduction; and the silver nanosheet interstitial layer is formed by coating with a silver nanosheet slurry.

[0024] Among them, the highly transparent glass is preferably explosion-proof glass or high-silicon glass, with a visible light transmittance of ≥90% and a haze value of ≤0.3%.

[0025] The pre-coating resin solution comprises the following components in percentage by mass: 60-70% resin matrix, 10-15% TiO2@SiO2 core-shell particles, 2-5% photoinitiator, 0.2-1% auxiliary agent, and 15-20% solvent. The resin matrix in the pre-coating resin solution is selected from at least one of acrylic resin, polyurethane acrylic resin, epoxy acrylic resin, and amino acrylic resin. The photoinitiator is preferably an acylphosphine oxide initiator (such as phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (TPO)), a macromolecular cleavage initiator (such as 2-hydroxy-2-methyl-1-phenyl-1-propanone (184)), or a cationic photoinitiator (such as diphenyliodonium hexafluorophosphate). The auxiliary agent is at least one of a leveling agent, a defoaming agent, an adhesion promoter, and a dispersant. The thickness of the pre-coating layer is 5-50 μm.

[0026] The silver nanowire ink comprises the following components by weight: 0.6% to 50% silver nanowire dispersion, 0.5% to 5.0% alcohol additive, 0.05% to 0.1% UV absorber, 0.01% to 0.1% dispersing additive, 0.01% to 0.5% film-forming additive, and the balance is deionized water. The silver nanowire solids content is 0.1% to 5%. The silver nanowires have a diameter of 10 to 50 nm and a length of 10 to 50 μm. The thickness of the magnetic field-oriented silver wire layer is 10 to 52 μm.

[0027] The preparation method of the silver nanowire dispersion comprises the following steps: adding ethylene glycol and a certain amount of halogen salt to a reaction kettle, dissolving the salt, and then adding polyvinyl pyrrolidone. After heating and dissolving the salt, a certain amount of silver nitrate / ethylene glycol solution is added all at once within 5 seconds to react. After the reaction is complete, a silver nanowire synthesis solution with uniform diameter is obtained. The silver nanowire synthesis solution is dialyzed to remove impurities, concentrated by centrifugation, and washed 2-3 times with a mixture of ethanol and water (3:7). The centrifuged product is then dispersed in deionized water and ultrasonically treated to obtain a silver nanowire dispersion with a concentration of 0.2-10% (mass percentage).

[0028] In the nano silver wire ink, the alcohol additive is selected from n-pentanol, isopropyl alcohol, 1,2-propylene glycol, etc.; the ultraviolet absorber is selected from at least one of benzotriazole, triazine, and ionic liquid ultraviolet absorbers; the dispersing aid is selected from block copolymer dispersing aids (such as vinyl pyrrolidone-vinyl acetate copolymer) and zwitterionic dispersing aids (such as lauramide propyl betaine); the film-forming aid is selected from at least one of polyether modified silicone (such as BYK-378), fluorocarbon polymer (such as Capstone FS-63), and silicone acrylate.

[0029] The silver nanosheet slurry comprises the following components by mass percentage: 1-3% silver nanosheets, 0.5-2% dispersant, 0.1-0.5% orientation control agent, 0-0.3% functional additive, and the balance being dispersion medium. The maximum planar dimension (L) / thickness (T) of the silver nanosheets should be ≥50. The dispersion medium is selected from at least one of glycol ethers, water-alcohol blends, and high-boiling-point ether esters. The dispersant is selected from at least one of polycarboxylate ammonium salts, hyperbranched polyurethane amines, and block copolymers. The orientation control agent is a cationic surfactant or a zwitterionic surfactant. The functional additive is preferably a pH adjuster or an antioxidant.

[0030] The protective layer is formed by coating and curing a protective layer resin solution. The protective layer resin solution comprises the following components by mass: 45-65% resin matrix, 5-8% curing agent, 0.2-0.5% additive, and 20-45% solvent. The resin matrix in the protective layer resin solution is selected from at least one of acrylic resin, polyurethane acrylic resin, epoxy acrylic resin, and amino acrylic resin. The curing agent is selected from dibenzoyl peroxide (BPO), isophorone diisocyanate (IPDI), and methylhexahydrophthalic anhydride (MHHPA) blocked HDI trimer. The additive is at least one of a leveling agent, a defoaming agent, a UV absorber, and a wetting agent. The protective layer thickness is 0.5-50 μm.

[0031] The method for preparing the highly transparent electromagnetic shielding glass comprises the following steps: (1) Substrate treatment High-transparency glass was selected as the substrate and subjected to alkali cleaning (5% NaOH solution, 45±2°C, ultrasonic cleaning for 10 min), acid cleaning (10% HNO3 solution, 25±1°C, soaking for 5 min), deionized water rinsing (18.2 MΩ·cm ultrapure water, three-stage countercurrent rinsing for 15 min), and nitrogen drying (purity 99.999%, air knife drying at 60°C, wind speed 10 m / s). (2) Pre-coating coating and curing Prepare the pre-coating resin solution and apply it to high-transparency glass using micro-gravure coating (screen count 180-220 lines / in, wet film thickness 14-16 μm). After preheating (infrared radiation at 75-85°C for 50-70 seconds) and UV curing (wavelength 360-370 nm, energy density 700-900 mJ / cm 2 ) forming a pre-coating layer; (3) Preparation of magnetic field oriented silver wire layer Silver nanowire ink was prepared and applied to the pre-coating layer via slit extrusion coating (gap 48-52 μm, speed 9-11 mm / s). A pulsed magnetic field (intensity 0.5-1.5 T, frequency 10-12 Hz, action time 30-40 s) was applied perpendicular to the high-transparency glass to align the silver nanowires. The ink was then dried by infrared irradiation (80-100°C gradient heating, heating rate 1.5-2.5°C / s, total time 115-125 s), laser scanning (wavelength 800-850 nm, power density 0.4-0.6 W / cm², scanning speed 45-55 mm / s), and field-assisted reduction (plasma reduction: Ar / H2=95:5, power 280-320 W, time 2.5-3.5 min; or UV reduction: 254±5 nm, light intensity 45-55 mW / cm²). 2 , time 4.5~5.5min), to obtain a magnetic field oriented silver wire layer; (4) Construction of silver nanosheet filling layer A silver nanosheet slurry was prepared and applied to the magnetically oriented silver wire layer using air knife spraying (atomization pressure 0.18-0.25 MPa, spraying distance 18-22 cm). The slurry was then dried in a gradient drying process (first stage: 80±5°C / 1.5-2.5 min → second stage: 100±5°C / 2.5-3.5 min → third stage: 120±5°C / 1.5-2.5 min) to form a silver nanosheet interstitial layer. (5) Protective layer coating and curing A protective layer resin solution was prepared and applied to the silver nanosheet interstitial layer by micro-gravure coating (screen count 140-160 lines / in, wet film thickness 18-22 μm). The solution was then cured (temperature 90-110°C, time 6-10 minutes) to form a protective layer.

[0032] Example 1 The method for preparing the high-transparency electromagnetic shielding glass of Example 1 comprises the following steps: (1) Substrate treatment Explosion-proof glass (6 mm thick) was selected as the substrate and subjected to alkaline cleaning (5% NaOH solution, 45 ± 2°C, ultrasonic cleaning for 10 min), acid cleaning (10% HNO3 solution, 25 ± 1°C, soaking for 5 min), deionized water rinsing (18.2 MΩ·cm ultrapure water, three-stage countercurrent rinsing for 15 min), and nitrogen drying (99.999% purity, air knife drying at 60°C, wind speed 10 m / s). (2) Pre-coating coating and curing A pre-coat resin solution was prepared, consisting of the following components by mass: 65% acrylic resin, 12% TiO2@SiO2 core-shell particles, 3% TPO photoinitiator, 0.3% BYK-333 leveling agent, 0.2% Tego Airex 920 defoamer, and 19.5% propylene glycol methyl ether acetate / ethanol (8:2, solvent). This solution was applied to explosion-proof glass using a micro-gravure coating process (screen count 200 lines / in, wet film thickness 15μm). The solution was then preheated (infrared radiation at 80°C for 60s) and UV-cured (wavelength 365nm, energy density 800mJ / cm 2 ) forming a pre-coating layer; (3) Preparation of magnetic field oriented silver wire layer A silver nanowire ink was prepared. The silver nanowire ink consisted of the following components by mass percentage: 20% silver nanowire dispersion (5% by mass), 2% n-pentanol, 0.08% ultraviolet absorber Tinuvin 1130, 0.05% PVP-VA copolymer, 0.2% BYK-378, and the balance deionized water. The ink was applied to the pre-coated surface via slit extrusion coating (gap 50 μm, speed 10 mm / s). A pulsed magnetic field (intensity 1.0 T, frequency 11 Hz, action time 35 s) was applied perpendicular to the direction of the high-transparency glass to align the silver nanowires. The ink was then dried by infrared irradiation (gradient heating at 90°C for 120 s) and laser scanning (wavelength 830 nm, power density 0.5 W / cm 2 , scanning speed 50 mm / s) and external field assisted reduction (plasma reduction: Ar / H2=95:5, power 300 W, time 3 min, to obtain a magnetic field oriented silver wire layer; (4) Construction of silver nanosheet filling layer A silver nanosheet slurry was prepared, comprising the following components by mass percentage: 2.5% silver nanosheets, 1.2% Disperbyk-110 dispersant, 0.3% cetyltrimethylammonium bromide orientation control agent, 0.1% antioxidant 1010, and the balance propylene glycol methyl ether dispersion medium. The slurry was applied to the magnetic field-oriented silver wire layer using air knife spraying (atomization pressure 0.22 MPa, spraying distance 20 cm), and then subjected to gradient drying (first stage: 80°C / 2 min → second stage: 100°C / 3 min → third stage: 120°C / 2 min) to form a silver nanosheet interstitial layer. (5) Protective layer coating and curing A protective layer resin solution was prepared. The solution consisted of the following components, by weight: 60% acrylic resin, 6% BPO curing agent, 0.3% BYK-333 leveling agent, 0.1% UV-1130 ultraviolet absorber, and 33.6% propylene glycol methyl ether acetate / ethanol (8:2, solvent). This solution was applied to the silver nanosheet interstitial layer using micro-gravure coating (screen count 150 lines / in, wet film thickness 20 μm). The solution was then cured (temperature 100°C, time 8 minutes) to form a protective layer.

[0033] Example 2 The method for preparing the high-transparency electromagnetic shielding glass of Example 2 comprises the following steps: (1) Substrate treatment High-silica glass (thickness 4.2 mm) was selected as the substrate and subjected to alkaline cleaning (5% NaOH solution, 45 ± 2°C, ultrasonic cleaning for 10 min), acid cleaning (10% HNO3 solution, 25 ± 1°C, soaking for 5 min), deionized water rinsing (18.2 MΩ·cm ultrapure water, three-stage countercurrent rinsing for 15 min), and nitrogen drying (purity 99.999%, air knife drying at 60°C, wind speed 10 m / s). (2) Pre-coating coating and curing A pre-coat resin solution was prepared, consisting of the following components by mass: 68% polyurethane acrylic resin, 10% TiO2@SiO2 core-shell particles, 4% 184 photoinitiator, 0.3% KH-570 leveling agent, 0.5% Tego Airex920 defoamer, and 17.5% ethyl acetate (solvent). The solution was applied to explosion-proof glass using a micro-gravure coating process (screen count 200 lines / in, wet film thickness 15μm). The solution was then preheated (infrared irradiation at 80°C for 60s) and UV-cured (wavelength 365nm, energy density 800mJ / cm 2 ) forming a pre-coating layer; (3) Preparation of magnetic field oriented silver wire layer A silver nanowire ink was prepared, which consisted of the following components by mass percentage: 40% silver nanowire dispersion (5% by mass), 3% 1,2-propylene glycol, 0.06% [BMIM][PF6] ionic liquid UV absorber, 0.08% lauramidopropyl betaine dispersant, 0.3% Capstone FS-63 film-forming aid, and the balance deionized water. The ink was applied to the pre-coated surface via slit extrusion coating (gap 50 μm, speed 10 mm / s). A pulsed magnetic field (intensity 0.8 T, frequency 10 Hz, action time 38 s) was applied perpendicular to the direction of the high-transparency glass to align the silver nanowires. The ink was then dried by infrared irradiation (gradient heating at 90°C for 120 s) and laser scanning (wavelength 830 nm, power density 0.5 W / cm 2 , scanning speed 50 mm / s) and external field assisted reduction (plasma reduction: Ar / H2=95:5, power 300 W, time 3 min, to obtain a magnetic field oriented silver wire layer; (4) Construction of silver nanosheet filling layer A silver nanosheet slurry was prepared, comprising the following components by mass percentage: 1.8% silver nanosheets, 1.5% hyperbranched polyurethane amine dispersant, 0.4% octadecyldimethylsulfonyl betaine orientation control agent, 0.1% antioxidant 1010, and the balance being a water / isopropyl alcohol (7:3, 70%) dispersion medium. The slurry was applied to the magnetic field-oriented silver wire layer using air knife spraying (atomization pressure 0.22 MPa, spraying distance 20 cm), and then subjected to gradient drying (first stage: 80°C / 2 min → second stage: 100°C / 3 min → third stage: 120°C / 2 min) to prepare a silver nanosheet interstitial layer. (5) Protective layer coating and curing A protective layer resin solution was prepared. The solution consisted of the following components, by mass: 55% polyurethane acrylic resin, 7% isophorone diisocyanate (IPDI) curing agent, 0.2% BYK-333 leveling agent, and 37.8% toluene (solvent). This solution was applied to the silver nanosheet interstitial layer using micro-gravure coating (screen count 150 lines / in, wet film thickness 20 μm). The solution was then cured (temperature 100°C, time 8 minutes) to form a protective layer.

[0034] Example 3 The method for preparing the high-transparency electromagnetic shielding glass of Example 3 comprises the following steps: (1) Substrate treatment Same as Example 1; (2) Pre-coating coating and curing A pre-coat resin solution was prepared, consisting of the following components by mass: 62% epoxy acrylic resin, 14% TiO2@SiO2 core-shell particles, 3.5% TPO photoinitiator, 0.4% Disperbyk-110 dispersant, and 20.1% cyclohexanone / ethanol (8:2, solvent). The solution was applied to explosion-proof glass using a micro-gravure coating process (screen count 200 lines / in, wet film thickness 15 μm). The solution was then preheated (infrared irradiation at 80°C for 60 seconds) and UV-cured (wavelength 365 nm, energy density 800 mJ / cm 2 ) forming a pre-coating layer; (3) Preparation of magnetic field oriented silver wire layer A silver nanowire ink was prepared, consisting of the following components by mass percentage: 50% silver nanowire dispersion (5% by mass), 4% isopropyl alcohol, 0.1% triazine UV-1577 UV absorber, 0.07% PVP-VA copolymer, 0.2% BYK-378, and the balance deionized water. The ink was applied to the pre-coated surface via slit extrusion coating (gap 50 μm, speed 10 mm / s). A pulsed magnetic field (intensity 0.8 T, frequency 10 Hz, action time 38 s) was applied perpendicular to the high-transparency glass to align the silver nanowires. The ink was then dried by infrared irradiation (gradient heating at 90°C for 120 s) and laser scanning (wavelength 830 nm, power density 0.5 W / cm 2 , scanning speed 50 mm / s) and external field assisted reduction (plasma reduction: Ar / H2=95:5, power 300 W, time 3 min, to obtain a magnetic field oriented silver wire layer; (4) Construction of silver nanosheet filling layer A silver nanosheet slurry was prepared, comprising the following components by mass percentage: 2.5% silver nanosheets, 1.0% polycarboxylate ammonium salt dispersant, 0.2% cetyltrimethylammonium bromide orientation control agent, 0.1% antioxidant 1010, and the balance being a water / isopropyl alcohol (7:3, 70%) dispersion medium. The slurry was applied to the magnetic field-oriented silver wire layer using air knife spraying (atomization pressure 0.22 MPa, spraying distance 20 cm), and then subjected to gradient drying (first stage: 80°C / 2 min → second stage: 100°C / 3 min → third stage: 120°C / 2 min) to prepare a silver nanosheet interstitial layer. (5) Protective layer coating and curing A protective layer resin solution was prepared. The solution consisted of the following components, by weight: 50% epoxy acrylic resin, 8% methylhexahydrophthalic anhydride (MHHPA) curing agent, 0.4% BYK-378 leveling agent, and 41.6% xylene (solvent). This solution was applied to the silver nanosheet interstitial layer using micro-gravure coating (screen count 150 lines / in, wet film thickness 20 μm). The solution was then cured (temperature 110°C, time 6 minutes) to form a protective layer.

[0035] The high-transparency electromagnetic shielding glasses of Examples 1-3 were subjected to performance tests, and the test results are shown in Table 1.

[0036] Table 1 As can be seen from Table 1, the electromagnetic shielding glass of the embodiment of the present invention has both excellent optical transparency and electromagnetic shielding effectiveness, as well as excellent mechanical and chemical stability.

[0037] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

[0038] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A highly transparent electromagnetic shielding glass, characterized in that: The invention comprises a highly transparent glass, a pre-coating layer, a conductive layer and a protective layer, which are designed in sequence from top to bottom. The pre-coating layer is formed by coating and curing a pre-coating resin solution containing TiO2@SiO2 core-shell particles. The conductive layer is composed of a magnetic field-oriented silver wire layer and a silver nanosheet interstitial layer. The preparation process of the magnetic field-oriented silver wire layer is as follows: nano silver wire ink is coated on the pre-coating layer, and a pulsed magnetic field is applied in a direction perpendicular to the highly transparent glass, followed by infrared drying, laser scanning and external field-assisted reduction. The silver nanosheet interstitial layer is formed by coating with a silver nanosheet slurry.

2. The high-transparency electromagnetic shielding glass according to claim 1, characterized in that: The highly transparent glass is explosion-proof glass or high-silicon glass.

3. The high-transparency electromagnetic shielding glass according to claim 1, characterized in that: The pre-coating resin solution includes the following components in percentage by mass: 60-70% resin matrix, 10-15% TiO2@SiO2 core-shell particles, 2-5% photoinitiator, 0.2-1% auxiliary agent, and 15-20% solvent.

4. The high-transparency electromagnetic shielding glass according to claim 3, characterized in that: The resin matrix in the pre-coating resin solution is selected from at least one of acrylic resin, polyurethane acrylic resin, epoxy acrylic resin, and amino acrylic resin.

5. The high-transparency electromagnetic shielding glass according to claim 1, characterized in that: The nano silver wire ink comprises the following components in percentage by mass: 0.6% to 50% nano silver wire dispersion, 0.5% to 5.0% alcohol additive, 0.05% to 0.1% ultraviolet absorber, 0.01% to 0.1% dispersing additive, 0.01% to 0.5% film-forming additive, and the balance is deionized water; wherein the solid content of the nano silver wire is 0.1% to 5%.

6. The high-transparency electromagnetic shielding glass according to claim 1, characterized in that: The silver nanosheet slurry comprises the following components by mass percentage: 1-3% silver nanosheets, 0.5-2% dispersant, 0.1-0.5% orientation control agent, 0-0.3% functional additive, and the balance is dispersion medium; the orientation control agent is a cationic surfactant or a zwitterionic surfactant.

7. The high-transparency electromagnetic shielding glass according to claim 1, characterized in that: The protective layer is formed by coating and curing a protective layer resin solution, wherein the protective layer resin solution comprises the following components by mass percentage: 45-65% resin matrix, 5-8% curing agent, 0.2-2% auxiliary agent, and 20-45% solvent.

8. A method for preparing the highly transparent electromagnetic shielding glass according to any one of claims 1 to 7, characterized in that: The steps include: (1) Substrate treatment Highly transparent glass was selected as the substrate and sequentially subjected to alkali washing, acid washing, deionized water rinsing and nitrogen drying; (2) Pre-coating coating and curing Preparing a pre-coating resin solution, applying the pre-coating resin solution on the high-transparency glass, and preheating and curing to form a pre-coating layer; (3) Preparation of magnetic field oriented silver wire layer Prepare nano silver wire ink, apply the nano silver wire ink to the pre-coating layer, apply a pulsed magnetic field perpendicular to the substrate to align the nano silver wires, and then perform infrared drying, laser scanning, and external field-assisted reduction to obtain a magnetic field-oriented silver wire layer; (4) Construction of silver nanosheet filling layer preparing a silver nanosheet slurry, coating the silver nanosheet slurry on the magnetic field-oriented silver wire layer, and then drying the silver nanosheet gap-filling layer; (5) Protective layer coating and curing A protective layer resin solution is prepared, coated on the silver nanosheet interstitial layer, and cured to form a protective layer.

9. The method for preparing high-transparency electromagnetic shielding glass according to claim 8, characterized in that: In step (3), the intensity of the pulsed magnetic field is 0.5~1.5T, and the frequency is 10~12Hz.

10. The method for preparing high-transparency electromagnetic shielding glass according to claim 8, characterized in that: In step (3), the temperature of the infrared drying is 80-100° C., the wavelength of the laser scanning is 800-850 nm, and the external field-assisted reduction is plasma-assisted reduction or ultraviolet photocatalytic reduction.

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