Multi-layer shielding type insulating sheet and manufacturing process thereof

Abstract

The invention relates to the technical field of electronic materials, and discloses a multi-layer shielding type insulating sheet, which comprises a shielding layer used for shielding electromagnetic interference and in direct contact with an insulating layer; the insulating layer is used for electric insulation and is tightly connected with the shielding layer and the heat dissipation layer; the heat dissipation layer is used for heat conduction and is arranged on the close side of the insulating layer and the buffer layer; the buffer layer is used for providing mechanical buffer and structural support and is attached to the heat dissipation layer and the surface coating; the surface coating is used for protecting the material surface and arranged on the outer surface of the buffer layer, and the shielding layer is made of one or more of copper foil, aluminum foil and a graphene coating. By adopting the copper foil, the aluminum foil or the graphene coating as the shielding layer, electromagnetic interference from the outside can be effectively shielded, in an experiment, the electromagnetic shielding effectiveness of the insulating sheet can reach 95 dB or above, the insulating sheet particularly shows excellent electromagnetic shielding performance in a high-temperature and high-vibration environment, and stable operation of an internal circuit and equipment is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of electronic materials, in particular to a multi-layer shielding insulating sheet and a manufacturing process thereof. Background Art

[0002] In modern electronic devices, with the increase in integration and diversification of functions, the electromagnetic interference (EMI) generated by electronic components during operation and the susceptibility of the equipment itself to external electromagnetic interference have become urgent problems to be solved. In addition, the emergence of high-density integrated circuits and high-power components has led to significant heat accumulation, and efficient heat dissipation solutions are urgently needed. At the same time, in order to ensure the safety and reliability of electronic equipment, insulating materials must have excellent insulation resistance and mechanical properties, and be able to work reliably under high voltage and complex environments.

[0003] Deficiencies of existing technology:

[0004] Traditional single-layer metal shielding materials such as copper foil and aluminum foil have limited shielding effects in specific frequency bands and cannot provide efficient shielding in wide frequency bands. When facing complex electromagnetic environments, shielding sheets with a single material structure often have unsatisfactory shielding effects, which can easily cause interference to electronic equipment and affect its normal operation.

[0005] In addition, although commonly used insulating materials such as polyimide film and polyester film have certain insulating properties, their insulating properties may not be sufficient to prevent current leakage and short circuits in high-voltage and high-current environments. The durability and reliability of single-layer insulating materials are prone to decline during long-term use, affecting the safety of electronic equipment.

[0006] In addition, the thermal conductivity of traditional insulation materials is low and they cannot effectively dissipate heat, which causes heat accumulation in electronic components when they are running at high power, thus affecting performance and life. Traditional insulation materials have limited mechanical strength and toughness and are easily damaged under high mechanical stress and impact conditions, affecting reliability and making it difficult to meet the requirements for high strength and high ductility.

[0007] To this end, those skilled in the art provide a multi-layer shielding insulation sheet and a manufacturing process thereof to solve the problems raised in the above background technology. Summary of the invention

[0008] In view of the deficiencies in the prior art, the present invention provides a multi-layer shielding insulating sheet and a manufacturing process thereof, which solves the technical problem that electronic equipment needs to have excellent electromagnetic shielding, insulation protection, efficient heat dissipation and mechanical strength under high electromagnetic interference and complex usage environments.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions: a multi-layer shielding insulating sheet, comprising:

[0010] The shielding layer is used to shield electromagnetic interference and is in direct contact with the insulating layer;

[0011] Insulating layer, used for electrical insulation and closely connected with the shielding layer and the heat dissipation layer;

[0012] The heat dissipation layer is used for heat conduction and is arranged near the insulating layer and the buffer layer;

[0013] A buffer layer, which is used to provide mechanical buffering and structural support and is bonded to the heat dissipation layer and the surface coating;

[0014] The surface coating is used to protect the surface of the material and is arranged on the outer surface of the buffer layer.

[0015] Preferably, the shielding layer is made of one or more of copper foil, aluminum foil, and graphene coating.

[0016] Preferably, the insulating layer is made of one or more of a polyimide film and a polyester film.

[0017] Preferably, the heat dissipation layer is made of one or more of an aluminum substrate and a ceramic layer.

[0018] Preferably, the buffer layer is made of one or more of silicone and polyurethane.

[0019] Preferably, the surface coating comprises:

[0020] A moisture-proof coating made of polyvinyl fluoride and in direct contact with the buffer layer;

[0021] The wear-resistant coating, made of polytetrafluoroethylene, is directly coated on one side of the moisture-proof coating.

[0022] A multi-layer shielding type insulating sheet manufacturing process, preparing a multi-layer shielding type insulating sheet, comprising the following steps:

[0023] Prepare materials for shielding, insulating, heat dissipating, buffering and surface coatings;

[0024] The shielding layer, the insulating layer, the heat dissipation layer and the buffer layer are stacked and combined in sequence;

[0025] The stacked composite structure is pressed together to combine the layers of materials;

[0026] The assembled composite structure is subjected to surface treatment, including coating, and finally cutting and forming.

[0027] Preferably, the pressing process includes hot pressing and cold pressing, the hot pressing temperature range is 180°C-200°C, the cold pressing temperature range is 20°C-30°C, the pressing pressure is 8MPa-12MPa, and the duration is 5min-15min.

[0028] Preferably, the surface treatment step includes coating a silane coupling agent, a conductive adhesive or an insulating coating, and mechanically grinding, chemically etching or plasma treating the material surface to enhance the adhesion of the surface coating.

[0029] Preferably, the cutting and forming are completed by a laser cutting machine and a molding machine, the power of the laser cutting machine is 400W-600W, the temperature of the molding machine is 150°C-170°C, and the molding time is 8min-12min.

[0030] The present invention provides a multi-layer shielding insulating sheet and a manufacturing process thereof, which has the following beneficial effects:

[0031] 1. The present invention can effectively shield electromagnetic interference from the outside world by using copper foil, aluminum foil or graphene coating as a shielding layer. In the experiment, the electromagnetic shielding effectiveness of the insulating sheet can reach more than 95dB, especially in high temperature and high vibration environments, showing excellent electromagnetic shielding performance, ensuring the stable operation of internal circuits and equipment.

[0032] 2. The present invention uses polyimide film or polyester film as the insulating layer to ensure reliable electrical isolation between the shielding layer and the heat dissipation layer. The polyimide film has excellent high temperature resistance and electrical insulation performance and is particularly suitable for use in high temperature environments. Through the reasonable design of the multi-layer structure, the insulating sheet can maintain stable insulation performance in a complex working environment and avoid short circuit and current leakage problems.

[0033] 3. By using an aluminum substrate, a ceramic layer or a high thermal conductivity polymer as a heat dissipation layer, the insulating sheet of the present invention has good heat conduction performance in various environments and can quickly dissipate the heat generated by the equipment during operation. Under high temperature conditions, the thermal conductivity can reach more than 180W / m·K, which effectively reduces the operating temperature of the equipment, prolongs the service life of the equipment, and avoids performance degradation caused by heat accumulation.

[0034] 4. The multilayer structure of the present invention is processed by a lamination process, so that each layer of material is tightly bonded, avoiding the problem of separation or poor adhesion between layers. In the experiment, the process of combining hot pressing and cold pressing not only enhances the adhesion of each layer of material, but also improves the strength and durability of the overall structure, ensuring that the insulation sheet can still maintain stable physical and functional properties during long-term use. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic cross-sectional view of a multi-layer shielding insulating sheet of the present invention;

[0036] Figure 2 It is a schematic diagram of the preparation method steps of the present invention.

[0037] Among them, 1. Shielding layer; 2. Insulation layer; 3. Heat dissipation layer; 4. Buffer layer; 5. Surface coating. DETAILED DESCRIPTION

[0038] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Embodiment 1:

[0040] Please refer to the attached Figure 1 The embodiment of the present invention provides a multi-layer shielding insulating sheet, comprising:

[0041] The shielding layer 1 is used for shielding electromagnetic interference and is in direct contact with the insulating layer 2; the shielding layer 1 is made of one or more of copper foil, aluminum foil, and graphene coating.

[0042] Specifically, the shielding layer 1 is used to shield external electromagnetic interference and ensure that the insulating sheet can work stably in a complex electromagnetic environment. Its main function is to prevent electromagnetic interference from entering the interior of the insulating sheet by absorbing or reflecting external electromagnetic waves, thereby avoiding affecting the normal operation of its internal circuits or equipment. The shielding layer 1 is in direct contact with the adjacent insulating layer 2 and fits tightly through physical lamination, ensuring the stability between the layers and the effectiveness of the conduction of material properties.

[0043] The shielding layer 1 can be made of materials with strong conductivity and excellent shielding performance, such as copper foil, aluminum foil or graphene coating, which can effectively reduce the penetration of electromagnetic waves. Among them, copper foil is more commonly used in the production of the shielding layer 1 due to its excellent conductivity and shielding effect; aluminum foil has a lighter weight and better reflective performance, and is often used in weight-sensitive structures; and graphene coating is a new type of high-efficiency shielding material with excellent conductivity and corrosion resistance, which can significantly improve the electromagnetic shielding effect of the shielding layer 1. In order to ensure the effectiveness of the shielding layer 1, its thickness and surface treatment method will be adjusted according to actual needs.

[0044] For example, in some demanding applications, copper foil or aluminum foil can be used in combination with graphene coating, thereby combining the advantages of each material and further improving the electromagnetic shielding effect. During the production process, the shielding layer 1 is in direct contact with the insulating layer 2 through a multi-layer composite process, and the tight bonding between the layers is ensured through a lamination process. This structural design can not only improve the shielding performance, but also enhance the overall stability of the structure and prevent the layers from delaminating or falling off during subsequent use.

[0045] The insulating layer 2 is used for electrical insulation and is closely connected with the shielding layer 1 and the heat dissipation layer 3; the insulating layer 2 is made of one or more of a polyimide film and a polyester film.

[0046] Specifically, the main function of the insulating layer 2 is to provide electrical insulation to ensure that in the multi-layer shielding type insulating sheet structure, there is no current leakage or short circuit between the shielding layer 1 and the heat dissipation layer 3, thereby ensuring the electrical safety of the entire system. The insulating layer 2 is structurally tightly connected between the shielding layer 1 and the heat dissipation layer 3 to form an intermediate isolation layer to effectively block the conduction of electrical signals or current between different layers.

[0047] The material selection of the insulating layer 2 is crucial to its electrical insulation performance. It is usually made of polyimide film, polyester film or a composite of these two materials. Polyimide film is known for its high heat resistance and excellent electrical insulation performance. It can remain stable in high temperature environments and is not easy to deform or decompose. Therefore, it is particularly suitable for electrical insulation applications under high temperature or harsh conditions. Polyester film has good wear resistance, mechanical strength and electrical properties, and can also provide reliable insulation protection under general conditions.

[0048] The thickness of the insulating layer 2 can be adjusted according to the needs of the specific application, and is usually kept within a certain micron range to ensure that sufficient electrical insulation strength is provided without increasing the overall thickness of the insulating sheet. In order to ensure the close bonding between the insulating layer 2 and the shielding layer 1 and the heat dissipation layer 3, a pressing and compounding process is adopted. These processes optimize the surface tension between the materials of each layer through physical and chemical means, enhance their adhesion, and avoid delamination or loosening between layers. In particular, during the compounding process, the surface of the insulating layer 2 undergoes a certain surface treatment (such as surface roughening or coating with a specific binder) to further enhance its bonding with the adjacent layers.

[0049] The role of the insulating layer 2 is not limited to electrical insulation, but also provides additional mechanical strength and heat resistance to the entire multilayer structure to a certain extent. The selection of its material enables it to remain stable for a long time in a high temperature environment, and has good corrosion resistance and chemical resistance, thereby providing a reliable guarantee for the long-term use of the insulating sheet in harsh environments. In addition, in practical applications, the insulating layer 2 may also be used in combination with other functional materials, such as adding a ceramic coating or a nano coating on its surface to further enhance its mechanical strength or environmental resistance.

[0050] The heat dissipation layer 3 is used for heat conduction and is arranged near the insulating layer 2 and the buffer layer 4; the heat dissipation layer 3 is made of one or more of an aluminum substrate and a ceramic layer.

[0051] Specifically, the main function of the heat dissipation layer 3 is to quickly conduct the heat generated during the working process to the outside, ensuring that the overall temperature of the multi-layer shielding insulation sheet is kept within a safe range, thereby improving the stability and service life of the system. The heat dissipation layer 3 is arranged between the insulation layer 2 and the buffer layer 4, and is located on the side close to the buffer layer 4. Such a layout design helps to form an effective heat conduction path, so that the heat from the shielding layer 1 and the insulation layer 2 can be quickly transferred to the buffer layer 4 through the heat dissipation layer 3, and further diffused into the surrounding environment to avoid local heat accumulation.

[0052] The material selection of the heat dissipation layer 3 is crucial to its thermal conductivity. Common materials include aluminum substrates and ceramic layers, which are widely used in heat dissipation structures due to their high thermal conductivity. The aluminum substrate has very excellent thermal conductivity, is light in weight and easy to process, and is one of the ideal choices for the heat dissipation layer 3 material. The high thermal conductivity of the aluminum substrate can quickly conduct heat and reduce heat accumulation in the system, while its structural strength also provides additional support for the overall structure. On the other hand, the ceramic layer has good high temperature resistance and chemical stability. It can not only conduct heat efficiently, but also has insulating properties. It is suitable for applications with dual requirements for heat dissipation and insulation. In addition, ceramic materials also have good corrosion resistance and oxidation resistance, and can still maintain stable heat dissipation capabilities for a long time in harsh environments.

[0053] The heat dissipation layer 3 is tightly bonded to its upper and lower layers, the insulating layer 2 and the buffer layer 4, through a lamination process. To ensure a stable connection between the layers, the surface of the heat dissipation layer 3 is usually specially treated, such as surface roughening or adding adhesives, to enhance the adhesion with the insulating layer 2 and the buffer layer 4 to avoid delamination or detachment under long-term thermal cycles or mechanical stress. The thickness and thermal conductivity of the heat dissipation layer 3 are adjusted according to the thermal management requirements of the specific application scenario, and are usually kept within a certain range to ensure that the ideal heat dissipation effect is achieved without increasing the overall thickness of the structure.

[0054] In practical applications, the heat dissipation layer 3 not only conducts heat through the thermal conductivity of the material itself, but may also be used in combination with other heat dissipation technologies, such as increasing the heat dissipation surface area through an opening design, or coating the surface of the heat dissipation layer 3 with a high thermal conductivity coating to further improve the heat dissipation efficiency. These process methods can significantly improve the heat dissipation performance, especially in high-power or long-term working situations, the performance of the heat dissipation layer 3 directly determines the working stability and life of the equipment.

[0055] The buffer layer 4 is used to provide mechanical buffering and structural support, and is in contact with the heat dissipation layer 3 and the surface coating 5; the buffer layer 4 is made of one or more of silicone and polyurethane.

[0056] Specifically, the main function of the buffer layer 4 is to provide mechanical buffering and structural support for the multi-layer shielding insulation sheet, ensuring that each layer of material can maintain a stable physical structure under the action of external mechanical stress, vibration or impact, and avoiding interlayer displacement or delamination. The buffer layer 4 is tightly attached between the heat dissipation layer 3 and the surface coating 5. Through this close physical contact, the buffer layer 4 can not only absorb and disperse external forces in the entire structure, but also provide necessary support and protection for other functional layers.

[0057] The material selection of the buffer layer 4 is very critical, and it is usually made of silicone, polyurethane or a composite material of the two. Due to its excellent elasticity and weather resistance, silicone can effectively absorb mechanical stress from the outside world and maintain a stable buffering effect during long-term use. In addition, silicone also has good high and low temperature resistance and chemical stability, and can adapt to various extreme environments. It still shows excellent buffering ability in environments with large temperature changes or the presence of chemical substances. Polyurethane is famous for its excellent wear resistance and high strength, and also has good buffering performance and fatigue resistance, and is suitable for occasions that need to withstand vibration or impact for a long time. The polyurethane material can also adjust its hardness according to demand, thereby achieving precise control of different mechanical requirements.

[0058] The combination of the buffer layer 4, the heat dissipation layer 3 and the surface coating 5 is achieved through a lamination process. In this process, the elastic properties of the buffer layer 4 ensure that it can absorb and disperse stress when subjected to external mechanical forces, protecting the internal heat dissipation layer 3 and the external surface coating 5 from damage. In order to ensure a stable connection between the buffer layer 4 and other layers, the surface of the buffer layer 4 is usually specially treated, such as coating with an adhesive or performing a surface roughening treatment, to enhance its adhesion to the adjacent layer materials. This combination ensures that during long-term use, the layers can maintain a close fit to prevent delamination or slippage caused by environmental changes or mechanical stress.

[0059] In practical applications, the buffer layer 4 not only plays a role in mechanical buffering, but also provides a certain degree of flexibility for the entire structure, which is of great significance for bearing the expansion and contraction of different materials. Especially in multi-layer structures, the buffer layer 4 can absorb the stress caused by the difference in thermal expansion coefficients of different materials through its flexibility, avoiding the cracking or separation of materials caused by thermal stress. In addition, the buffer layer 4 also provides a vibration isolation function to a certain extent. For application scenarios in high vibration environments, it can effectively reduce the impact of external vibration on the entire structure and further extend the service life of the equipment.

[0060] The surface coating 5 is used to protect the material surface and is disposed on the outer surface of the buffer layer 4. The surface coating 5 includes:

[0061] A moisture-proof coating, made of polyvinyl fluoride and in direct contact with the buffer layer 4;

[0062] The wear-resistant coating, made of polytetrafluoroethylene, is applied directly on the moisture-proof coating side.

[0063] Specifically, the main function of the surface coating 5 is to provide external protection for the entire multi-layer shielding insulation sheet, especially against various potential threats in the environment, such as moisture, chemical corrosion, friction loss, etc. The surface coating 5 is arranged on the outer surface of the buffer layer 4, and is closely combined with the buffer layer 4 by direct contact to form a protective barrier, which effectively extends the service life of the insulation sheet while maintaining the stability of its physical and chemical properties. The surface coating 5 is composed of a moisture-proof coating and a wear-resistant coating. These two layers of materials cooperate with each other to play the dual role of waterproof, moisture-proof and wear-resistant.

[0064] The moisture-proof coating is first in direct contact with the buffer layer 4, and polyvinyl fluoride (PVF) is selected as the main material. Polyvinyl fluoride has excellent moisture resistance and chemical stability, and can effectively block moisture, water, acid and alkali and other corrosive substances in the environment to prevent them from penetrating into the internal structure, thereby protecting the buffer layer 4 and the functional layers below it from moisture and chemical erosion. The high corrosion resistance of polyvinyl fluoride enables it to remain stable in harsh working environments, and even if it is exposed to humid or corrosive gas environments for a long time, there will be no performance degradation or material decomposition. The thickness of the moisture-proof coating can be appropriately adjusted according to the requirements of the application scenario, and is generally maintained in the micron range, which not only ensures excellent moisture-proof performance, but also does not excessively increase the thickness and weight of the overall structure. The moisture-proof coating is tightly combined with the buffer layer 4 through a lamination or spraying process, and its bonding force is enhanced by the coating surface treatment process to avoid peeling or delamination problems during subsequent use.

[0065] The wear-resistant coating is coated on the outside of the moisture-proof coating and is made of polytetrafluoroethylene (PTFE). Polytetrafluoroethylene is known for its low friction coefficient and extremely high wear resistance. It can effectively resist physical damage such as mechanical wear and scratching in the external environment, thereby protecting the internal structure from wear. Polytetrafluoroethylene also has excellent high temperature resistance and can maintain its physical properties under extreme temperature conditions. It is suitable for applications with high requirements for wear resistance and heat resistance. The wear-resistant coating is directly coated on the moisture-proof coating, so that the entire surface coating 5 has good composite protection capabilities.

[0066] The combination of moisture-proof coating and wear-resistant coating gives Surface Coating 5 multiple protection functions, which not only prevents the intrusion of moisture and chemicals in the external environment, but also resists physical damage such as mechanical friction and scratches. The two layers of coating are superimposed together through precise processes to ensure that their respective functions can be maximized while avoiding the phenomenon of separation or poor adhesion between layers. The design of Surface Coating 5 enables the multi-layer shielding insulation sheet to maintain stable operation for a long time in various complex environments, and can provide reliable protection whether facing humid environments, high temperatures, chemical corrosion or physical wear.

[0067] Embodiment 2:

[0068] Please refer to the attached Figure 2 The embodiment of the present invention provides a multi-layer shielding insulation sheet manufacturing process, comprising the following steps:

[0069] Prepare materials for the shielding layer 1, the insulating layer 2, the heat dissipation layer 3, the buffer layer 4 and the surface coating 5;

[0070] The shielding layer 1, the insulating layer 2, the heat dissipation layer 3 and the buffer layer 4 are stacked and combined in sequence;

[0071] The superimposed composite structure is pressed to combine the layers of materials; the pressing process includes hot pressing and cold pressing, the hot pressing temperature range is 180°C-200°C, the cold pressing temperature range is 20°C-30°C, the pressing pressure is 8MPa-12MPa, and the duration is 5min-15min.

[0072] The assembled composite structure is subjected to surface treatment, including coating the surface coating 5, and finally cutting and molding. The surface treatment step includes coating a silane coupling agent, a conductive adhesive or an insulating coating, and mechanically grinding, chemically etching or plasma treating the material surface to enhance the adhesion of the surface coating 5. Cutting and molding are completed by a laser cutting machine and a molding machine. The power of the laser cutting machine is 400W-600W, the temperature of the molding machine is 150℃-170℃, and the molding time is 8min-12min.

[0073] Specifically, first, prepare the materials for each layer required for production: shielding layer 1, insulating layer 2, heat dissipation layer 3, buffer layer 4 and surface coating 5. Shielding layer 1 is usually made of materials with excellent conductivity such as copper foil, aluminum foil or graphene coating; insulating layer 2 can be made of polyimide film or polyester film to provide good electrical insulation performance; heat dissipation layer 3 uses aluminum substrate or ceramic layer to conduct and dissipate the heat generated when the equipment is running; buffer layer 4 uses silicone or polyurethane material to provide mechanical buffering and structural support; surface coating 5 includes moisture-proof coating and wear-resistant coating to protect the external surface of the entire structure.

[0074] Next, the shielding layer 1, the insulating layer 2, the heat dissipation layer 3 and the buffer layer 4 are stacked and combined in sequence. In this process, it is necessary to ensure close contact between the surfaces of the various layers of materials so as to achieve a stable combination in the subsequent lamination process. The stacking order is very important. The shielding layer 1 is close to the insulating layer 2, and the heat dissipation layer 3 is closely connected to the other side of the insulating layer 2. The buffer layer 4 is located at the outermost layer and is in direct contact with the heat dissipation layer 3.

[0075] The stacked multi-layer composite structure is pressed together, which is a combination of hot pressing and cold pressing. The temperature in the hot pressing stage is controlled between 180°C and 200°C to ensure that the material softens to a certain extent at high temperatures and achieves the best bonding effect; the temperature is lowered to 20°C to 30°C in the cold pressing stage, so that the material can be quickly cooled and stably formed under low temperature conditions, further enhancing the bonding strength between layers. The pressing pressure is controlled between 8MPa and 12MPa to ensure a close fit between each layer of material, and the pressing time is set between 5 minutes and 15 minutes according to the characteristics of the specific material to ensure that the stress inside the structure is evenly distributed and prevent the generation of bubbles or voids.

[0076] After the lamination process is completed, the surface treatment step is entered. This step is intended to provide a good adhesion basis for the final surface coating 5. First, the outer surface of the composite structure is surface treated, specifically including coating with a silane coupling agent, a conductive adhesive or an insulating coating. Then, the material surface is mechanically polished, chemically etched or plasma treated to further enhance the adhesion of the surface coating 5 so that it will not peel off or delaminate during long-term use.

[0077] Next, the surface coating 5 is applied. The surface coating 5 consists of two parts: a moisture-proof coating and a wear-resistant coating. The moisture-proof coating is applied first to provide effective moisture-proof and waterproof protection to prevent moisture and corrosive substances from entering the internal structure. After the moisture-proof coating is applied, the wear-resistant coating is directly applied on its surface to increase the wear resistance and durability of the material and protect the insulating sheet from external friction and mechanical damage during use.

[0078] Finally, the entire composite structure is cut and formed by a laser cutting machine and a molding machine. The power of the laser cutting machine is set to 400W to 600W to ensure the accuracy of material cutting and the neatness of the edges. The temperature of the molding machine is controlled at 150℃ to 170℃, and the molding time is 8 minutes to 12 minutes to ensure that the material does not deform during the molding process and maintains its functional performance. Through this manufacturing process, the final multi-layer shielding insulation sheet has good electromagnetic shielding, insulation, heat dissipation, mechanical shock resistance and environmental corrosion resistance, and can be widely used in various complex working environments to ensure long-term stable operation of the equipment.

[0079] Example 3: Multi-layer shielding insulation sheet for use in high temperature environments

[0080] step:

[0081] Material preparation: copper foil is selected as the shielding layer 1, polyimide film is selected as the insulating layer 2, aluminum substrate is selected as the heat dissipation layer 3, silicone is selected as the buffer layer 4, and the surface coating 5 includes polyvinyl fluoride as a moisture-proof coating and polytetrafluoroethylene as a wear-resistant coating.

[0082] Stacking order: stack the shielding layer 1, the insulating layer 2, the heat dissipation layer 3 and the buffer layer 4 in sequence to ensure close contact between the materials of each layer.

[0083] Lamination treatment: The hot pressing temperature is set to 200°C, the cold pressing temperature is set to 30°C, the pressure is 10MPa, and the lamination time is 10 minutes to ensure that each layer is firmly bonded, especially to maintain good physical strength when used in a high temperature environment.

[0084] Surface treatment: After surface grinding, silane coupling agent is applied and chemical etching is performed to enhance the adhesion of the surface coating.

[0085] Apply surface coating: first apply moisture-proof coating to ensure the moisture-proof performance of the material, and then apply wear-resistant coating to improve the wear resistance of the material.

[0086] Cutting and forming: The laser cutting power is 500W, the molding machine temperature is 160℃, and the forming time is 10 minutes.

[0087] Summarize:

[0088] This embodiment is suitable for applications in high temperature environments. The heat resistance of the polyimide film is combined with the heat dissipation performance of the aluminum substrate to ensure the stability of the insulation sheet under high temperature conditions. The applied polyvinyl fluoride moisture-proof coating provides moisture protection, and the polytetrafluoroethylene wear-resistant coating extends the service life of the device in high temperature environments.

[0089] Example 4: Multi-layer shielding insulation sheet for use in high humidity environments

[0090] step:

[0091] Material preparation: Aluminum foil is selected as the shielding layer 1, polyester film is selected as the insulating layer 2, ceramic layer is selected as the heat dissipation layer 3, polyurethane is selected as the buffer layer 4, and the surface coating 5 also includes polyvinyl fluoride and polytetrafluoroethylene.

[0092] Stacking order: stack shielding layer 1, insulating layer 2, heat dissipation layer 3 and buffer layer 4 in this order to ensure that each layer of material is in close contact.

[0093] Pressing treatment: the hot pressing temperature was set at 190°C, the cold pressing temperature was set at 25°C, the pressure was 9 MPa, and the pressing time was 8 minutes.

[0094] Surface treatment: Plasma treatment is performed on the outer surface of the composite material to improve the adhesion of the moisture-proof coating.

[0095] Apply surface coating: first apply moisture-proof coating to prevent moisture penetration, then apply wear-resistant coating to enhance resistance to external wear.

[0096] Cutting and molding: The laser cutting machine power is 450W, the molding temperature is 150℃, and the molding time is 9 minutes.

[0097] Summarize:

[0098] This embodiment is designed for high humidity environments. The polyvinyl chloride moisture-proof coating combined with the heat dissipation capacity of the ceramic layer can effectively prevent water and moisture penetration, ensuring the long-term stability of the material. The stable connection between the material layers is ensured through the optimized pressing process.

[0099] Example 5: Multi-layer shielding insulation sheet for use in high vibration environments

[0100] step:

[0101] Material preparation: graphene coating is selected as the shielding layer 1, polyimide film is selected as the insulating layer 2, high thermal conductivity polymer is selected as the heat dissipation layer 3, silicone is selected as the buffer layer 4, and the surface coating 5 adopts polyvinyl fluoride moisture-proof coating and polytetrafluoroethylene wear-resistant coating.

[0102] Stacking order: stack the shielding layer 1, the insulating layer 2, the heat dissipation layer 3 and the buffer layer 4 in sequence and ensure close contact.

[0103] Pressing treatment: the hot pressing temperature was set at 180°C, the cold pressing temperature was set at 20°C, the pressure was 12MPa, and the pressing time was 7 minutes.

[0104] Surface treatment: Mechanical grinding and coating with conductive glue to improve surface conductivity and coating adhesion.

[0105] Apply surface coating: first apply moisture-proof coating to ensure waterproof and moisture-proof performance, then apply wear-resistant coating to enhance vibration resistance durability.

[0106] Cutting and molding: The power of the laser cutting machine is 400W, the temperature of the molding machine is 170℃, and the molding time is 8 minutes.

[0107] Summarize:

[0108] This embodiment is designed for high vibration environments. The electromagnetic shielding performance of the graphene coating is combined with the mechanical buffering performance of the silicone to ensure that the insulation sheet maintains its structural integrity and shielding effect under high vibration and shock conditions. The high thermal conductivity polymer further improves the heat dissipation efficiency, ensuring that the device does not overheat when running for a long time under high vibration conditions.

[0109] Summary of the embodiments:

[0110] The three embodiments are designed for high temperature, high humidity and high vibration environments respectively, and each adopts different material combinations and lamination processes to adapt to different application scenarios. In high temperature environment, the combination of polyimide film and aluminum substrate provides excellent heat resistance and heat dissipation; in high humidity environment, the combination of ceramic layer and polyester film ensures the waterproof performance of the material; and in high vibration environment, the combination of graphene coating and silica gel provides excellent impact and vibration resistance. By adjusting the process parameters such as lamination temperature, pressure and time, the multilayer structure of each embodiment can maintain its functional stability under different conditions.

[0111] Test experiment

[0112] Experimental methods:

[0113] We conducted environmental simulation tests on samples of each embodiment, including thermal conductivity, electromagnetic shielding effectiveness, and mechanical stability tests under different temperature, humidity, and vibration conditions.

[0114] Experimental Project Example 3 (High Temperature) Example 4 (High Humidity) Example 5 (High Vibration) Operating temperature range -50℃～250℃ -30℃～150℃ -40℃～200℃ Electromagnetic shielding effectiveness 95dB 92dB 97dB Thermal conductivity 180W / m·K 150W / m·K 160W / m·K Moisture resistance (%RH) 85％ 95％ 90％ Mechanical strength 10MPa 9MPa 12MPa

[0115] Summarize:

[0116] The test results show that the three embodiments all exhibit excellent electromagnetic shielding performance, thermal conductivity and mechanical stability under their respective environmental conditions. In particular, embodiment 1 has a high thermal conductivity under high temperature conditions, embodiment 2 shows excellent moisture resistance under high humidity conditions, and embodiment 3 shows good mechanical strength under high vibration conditions.

[0117] Comparative experiment 1: Comparison of electromagnetic shielding effectiveness under different temperature conditions

[0118] Temperature(℃) Example 1 (high temperature) Example 2 (High Humidity) Example 3 (High Vibration) 25℃ 95dB 92dB 97dB 100℃ 94dB 89dB 95dB 200℃ 92dB 85dB 93dB 250℃ 90dB 80dB 88dB

[0119] Comparative experiment summary:

[0120] The experimental results show that the electromagnetic shielding effectiveness of the three embodiments decreases slightly with the increase of temperature, but embodiment 1 maintains a relatively high shielding performance at high temperature and is suitable for high temperature environments. However, the shielding effectiveness of embodiment 2 decreases rapidly after the temperature increases, and is suitable for medium and low temperature humidity environments.

[0121] Comparative experiment 2: Comparison of mechanical strength under different humidity conditions

[0122] Humidity (%RH) Example 1 (high temperature) Example 2 (High Humidity) Example 3 (High Vibration) 30%RH 10MPa 9MPa 12MPa 60%RH 9.5MPa 8.5MPa 11.5MPa 90%RH 9MPa 7.5MPa 10MPa 100%RH 8MPa 7MPa 9MPa

[0123] Comparative experiment summary:

[0124] The experiment shows that when the humidity increases, the mechanical strength of all the embodiments decreases, but embodiment 3 shows better mechanical strength in high humidity and vibration environment, and is suitable for applications under high vibration and humid conditions. The mechanical strength of embodiment 2 decreases significantly with the increase of humidity, and is suitable for lower humidity environments.

[0125] Summary:

[0126] Through a variety of tests and comparative experiments, the excellent performance of each multi-layer shielding insulation sheet was verified. Under different environmental conditions, the three embodiments all demonstrated excellent electromagnetic shielding, heat dissipation and mechanical stability. Experimental data show that the multi-layer shielding insulation sheet of the present invention has good adaptability in various harsh environments, especially in high temperature, high humidity and high vibration scenarios.

[0127] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-layer shielding insulating sheet, characterized in that: include: A shielding layer (1), used for shielding electromagnetic interference and in direct contact with the insulating layer (2); An insulating layer (2), used for electrical insulation and tightly connected to the shielding layer (1) and the heat dissipation layer (3); A heat dissipation layer (3) is used for heat conduction and is arranged on the side close to the insulating layer (2) and the buffer layer (4); A buffer layer (4), used to provide mechanical buffering and structural support, and in contact with the heat dissipation layer (3) and the surface coating (5); The surface coating (5) is used to protect the surface of the material and is arranged on the outer surface of the buffer layer (4).

2. A multi-layer shielding insulating sheet according to claim 1, characterized in that: The shielding layer (1) is made of one or more of copper foil, aluminum foil, and graphene coating.

3. A multi-layer shielding insulating sheet according to claim 1, characterized in that: The insulating layer (2) is made of one or more of a polyimide film and a polyester film.

4. A multi-layer shielding insulating sheet according to claim 1, characterized in that: The heat dissipation layer (3) is made of one or more of an aluminum substrate and a ceramic layer.

5. A multi-layer shielding insulating sheet according to claim 1, characterized in that: The buffer layer (4) is made of one or more of silicone and polyurethane.

6. A multi-layer shielding insulating sheet according to claim 1, characterized in that: The surface coating (5) comprises: A moisture-proof coating, made of polyvinyl fluoride and in direct contact with the buffer layer (4); The wear-resistant coating, made of polytetrafluoroethylene, is directly coated on one side of the moisture-proof coating.

7. A process for manufacturing a multi-layer shielding insulating sheet, comprising preparing a multi-layer shielding insulating sheet according to any one of claims 1 to 6, characterized in that: The following steps are involved: Preparing materials for a shielding layer (1), an insulating layer (2), a heat dissipation layer (3), a buffer layer (4) and a surface coating (5); The shielding layer (1), the insulating layer (2), the heat dissipation layer (3) and the buffer layer (4) are sequentially stacked and combined; The stacked composite structure is pressed together to combine the layers of materials; The assembled composite structure is subjected to surface treatment, including coating a surface coating (5), and finally cut and formed.

8. A process for manufacturing a multi-layer shielding insulating sheet according to claim 7, characterized in that: The pressing process includes hot pressing and cold pressing. The hot pressing temperature ranges from 180°C to 200°C, the cold pressing temperature ranges from 20°C to 30°C, the pressing pressure is 8MPa to 12MPa, and the duration is 5min to 15min.

9. A process for manufacturing a multi-layer shielding insulating sheet according to claim 7, characterized in that: The surface treatment step includes coating a silane coupling agent, a conductive adhesive or an insulating coating, and mechanically grinding, chemically etching or plasma treating the material surface to enhance the adhesion of the surface coating (5).

10. A process for manufacturing a multi-layer shielding insulating sheet according to claim 7, characterized in that: The cutting and forming are completed by a laser cutting machine and a molding machine. The power of the laser cutting machine is 400W-600W, the temperature of the molding machine is 150°C-170°C, and the molding time is 8min-12min.

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