A hollow conductive shielded cushion tubular member and method of manufacture

Abstract

The application provides a hollow conductive shielding buffer tubular member and a preparation method, which can realize the comprehensive performance of ultra-low compression resilience, ultra-high conductive conduction, high resilience recovery rate, easy disassembly and maintenance, long-term fatigue resistance, and is suitable for various high-precision electronic products, gap filling of screen assemblies, conductive grounding and electromagnetic shielding scenes; the hollow conductive shielding buffer tubular member comprises a conductive wrapping layer, a PI film substrate layer and a hot melt adhesive layer; the hot melt adhesive layer is arranged between the conductive wrapping layer and the PI film substrate layer, the hot melt adhesive layer composites and fixes the conductive wrapping layer on the outer surface of the PI film substrate layer, the conductive wrapping layer is wrapped on the outside of the PI film substrate layer in a coating forming mode, and the conductive wrapping layer and the PI film substrate layer cooperatively form a sleeve type hollow structure.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic shielding accessories for electronic devices, specifically to a hollow conductive shielding buffer tubular component and its preparation method. Background Technology

[0002] In the current electronic product assembly process, assembly gaps and machining tolerances are common in components such as housings, screens, and motherboards. To meet the requirements of local conductive connections, reliable grounding, and electromagnetic shielding, conductive foam is commonly used as an elastic conductive filling medium in the industry. However, existing conductive buffer components have many defects and cannot meet the usage requirements of high-precision screen electronic products. Firstly, traditional conductive foam with foam core and omnidirectional conductive foam are solid elastic structures. However, for components with large gaps and large tolerances, a high compression ratio assembly method is required. This increases the product size and leads to a significant increase in compression and rebound force. Moreover, the high rebound pressure acts directly on the screen component, which can easily cause defects such as spots, water ripples, and local indentations in the screen display area, seriously affecting the product display quality and appearance yield. Secondly, all-around conductive foam has problems such as low compression recovery rate and easy fatigue collapse after long-term use. After long-term service, it may experience failures such as conduction interruption, shielding failure, and loose gap filling, resulting in poor product reliability. Third, although conductive gel-based filling media can achieve low-rebound filling, the gel has poor fluidity and low bonding accuracy before curing. After curing, the whole sticks together, making subsequent equipment disassembly and maintenance, component maintenance, and parts replacement extremely difficult. Moreover, the gel is prone to aging and cracking and conductivity decay with long-term use, so long-term reliability cannot be guaranteed. In summary, existing conductive buffer components cannot simultaneously meet the core requirements of low compression rebound force, high conductivity, high rebound recovery rate, easy disassembly and maintenance, and long-term high reliability. Summary of the Invention

[0003] To address the aforementioned issues, this invention provides a hollow conductive shielding buffer tubular component and its preparation method, which achieves comprehensive performance including ultra-low compression rebound, ultra-high conductivity, high rebound recovery rate, easy disassembly and maintenance, and long-term fatigue resistance. It is suitable for various high-precision electronic products, gap filling of screen components, conductive grounding, and electromagnetic shielding scenarios.

[0004] The present invention adopts the following technical solution: a hollow conductive shielding buffer tubular component, comprising a conductive coating layer, a PI film substrate layer, and a hot melt adhesive layer; the hot melt adhesive layer is disposed between the conductive coating layer and the PI film substrate layer, the hot melt adhesive layer composites and fixes the conductive coating layer to the outer surface of the PI film substrate layer, and the conductive coating layer is coated on the outside of the PI film substrate layer by an overmolding method, the conductive coating layer and the PI film substrate layer cooperate to form a sleeve-type hollow structure.

[0005] Furthermore, the conductive coating layer is made of, but is not limited to, conductive cloth, conductive non-woven fabric, or conductive polyimide; the thickness of the conductive coating layer is no greater than 0.02 mm. Furthermore, the thickness of the PI film substrate layer is no greater than 0.02 mm; Furthermore, conductive adhesive is uniformly coated on a pre-set bonding area on the outside of the conductive wrapping layer, and the thickness of the conductive adhesive is 0.05mm~0.15mm; Furthermore, the hot melt adhesive layer is an adhesive layer formed by curing a PET hot melt adhesive film, and the hot melt adhesive layer covers the bonding surface between the conductive wrapping layer and the PI film substrate layer; Furthermore, the PI film substrate layer constitutes the inner support substrate of the sleeve, and the conductive wrapping layer constitutes the outer conductive layer of the sleeve; the conductive wrapping layer completely covers the outer peripheral surface of the PI film substrate layer. Furthermore, the sleeve is an integrally formed structure; the sleeve wall is composed of the PI film substrate layer, the hot melt adhesive layer, and the conductive coating layer stacked sequentially from the inside to the outside. A method for preparing a hollow conductive shielding buffer tubular component includes the following processing steps: S1. Select a hot melt adhesive film of a preset specification and use a die-cutting device to cut the hot melt adhesive film into a sheet that matches the bonding size of the conductive coating layer and the PI film substrate layer. S2. The hot melt adhesive film is completely filled into the gap between the conductive coating layer and the PI film substrate layer. The hot melt adhesive film is melted and solidified by hot pressing, so that the conductive coating layer and the PI film substrate layer are composite and fixed to obtain an integrated composite substrate. S3. Place the integrated composite substrate prepared in step S2 into a matching mold, and use the shaping structure of the mold to bend and shape the integrated composite substrate so that the conductive coating layer completely covers the outer surface of the PI film substrate. Then, shape and cure the substrate. Next, apply conductive adhesive evenly to the preset bonding area on the outside of the shaped and cured conductive coating layer, and after curing at room temperature, attach the release paper to form a sleeve-type integrated structure with the conductive coating layer covering the PI film substrate.

[0006] Furthermore, in step S2, the hot-pressing temperature is 80℃~120℃, the hot-pressing pressure is 0.2MPa~0.5MPa, and the hot-pressing holding time is 3s~10s; Furthermore, in step S3, after the coating and molding are completed, the sleeve structure is cured by room temperature air cooling, and the curing time is 5s~15s.

[0007] The beneficial effects of this invention are that the sleeve-type hollow structure formed by the composite of the conductive coating layer, the PI film substrate layer, and the hot melt adhesive layer has a high hollow ratio. When under pressure, the hollow cavity can buffer and relieve the force, greatly reducing the compression rebound force. Even under conditions of large gap and high compression ratio, it can still maintain low stress adhesion, fundamentally solving the defects such as screen top pressure spots, water ripples, and indentations, greatly improving the display quality and yield of electronic products, and has strong fatigue resistance. At the same time, it can be adapted to the assembly scenarios of various consumer electronics, automotive electronics, and precision industrial control equipment, and has good application value. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the unfolded structure of the present invention; Figure 2 This is a schematic diagram of the molded three-dimensional structure of Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the molding cross-sectional structure of Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the compressed structure of Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the molded three-dimensional structure of Embodiment 2 of the present invention. Detailed Implementation

[0009] like Figure 1 As shown, a hollow conductive shielding buffer tubular component of the present invention includes a conductive wrapping layer 1, a PI film substrate layer 2, and a hot melt adhesive layer 3; the hot melt adhesive layer 3 is disposed between the conductive wrapping layer 1 and the PI film substrate layer 2, and the hot melt adhesive layer 3 composites and fixes the conductive wrapping layer 1 to the outer surface of the PI film substrate layer 2, and the conductive wrapping layer 1 is wrapped around the outside of the PI film substrate layer 2 by a coating molding method, and the conductive wrapping layer 1 and the PI film substrate layer 2 cooperate to form a sleeve-type hollow structure.

[0010] The conductive wrapping layer 1 is made of materials including, but not limited to, conductive cloth, conductive non-woven fabric, and conductive polyimide. Tin-plated polyimide, nickel-plated polyimide, metal foil, flexible absorbing material, thermally conductive graphite sheet, or other conductive composite materials can also be selected according to requirements. The thickness of the conductive wrapping layer 1 is 0.02 mm. The thickness of the PI film substrate layer 2 is 0.02 mm. Conductive adhesive 4 is uniformly coated on the pre-set bonding area on the outside of the conductive wrapping layer 1. The thickness of the conductive adhesive 4 is 0.05 mm, forming a detachable bonding layer.

[0011] The hot melt adhesive layer 3 is an adhesive layer formed by curing a PET hot melt adhesive film. The hot melt adhesive layer 3 covers the bonding surface between the conductive wrapping layer 1 and the PI film substrate layer 2.

[0012] The PI film substrate layer 2 constitutes the inner support substrate of the sleeve, and the conductive wrapping layer 1 constitutes the outer conductive layer of the sleeve; the conductive wrapping layer 1 completely covers the outer peripheral surface of the PI film substrate layer 2.

[0013] The sleeve is an integral enclosed molding structure; the sleeve wall is composed of a PI film substrate layer 2, a hot melt adhesive layer 3, and a conductive wrapping layer 1 stacked from the inside to the outside.

[0014] A method for preparing a hollow conductive shielding buffer tubular component includes the following processing steps: S1. Select a hot melt adhesive film of a preset specification and use a die-cutting device to cut the hot melt adhesive film into a sheet that matches the bonding size of the conductive wrapping layer 1 and the PI film substrate layer 2. S2. The hot melt adhesive film is completely filled between the bonding gaps of the conductive coating layer 1 and the PI film substrate layer 2. The hot melt adhesive film is melted and solidified by hot pressing, so that the conductive coating layer 1 and the PI film substrate layer 2 are compositely fixed to obtain an integrated composite substrate. Furthermore, in step S2, the hot-pressing temperature is 80℃~120℃, the hot-pressing pressure is 0.2MPa~0.5MPa, and the hot-pressing holding time is 3s~10s; S3. Place the integrated composite substrate prepared in step S2 into a mold with matching specifications. Use the shaping structure of the mold to bend and shape the integrated composite substrate so that the conductive coating layer 1 completely covers the outer surface of the PI film substrate layer 2. Shape and solidify the shaped substrate into a sleeve structure. After the coating and shaping are completed, the sleeve structure is solidified by room temperature air cooling for 5s to 15s. Then, the conductive adhesive 4 is evenly applied to the preset bonding area on the outside of the shaped and solidified conductive coating layer 1. After room temperature curing, the release paper is attached to form a sleeve-type integrated structure with the conductive coating layer 1 covering the PI film substrate layer 2. Then, according to the product assembly requirements, the sleeve-type integrated structure is precisely cut into the corresponding customized size and length to become the finished product.

[0015] When bending the integrated composite substrate, the two ends of the substrate can be partially overlapped; alternatively, they can be left unoverlapped with a gap. This bending configuration depends on the specific circumstances. like Figures 2-4 As shown in Example 1, the two ends of the substrate are partially overlapped, so the bottom of the prepared sleeve has a portion of the substrate superimposed. The superimposed and connected parts are fixed by hot melt adhesive layer 3, and conductive adhesive 4 is applied to the outside of the conductive wrapping layer 1 at the bottom of the sleeve.

[0016] like Figure 5 As shown in Example 2, there is a gap at both ends of the substrate, and the bottom of the prepared sleeve product forms an opening through the gap. At this time, the conductive adhesive 4 is coated on the outside of the conductive wrapping layer 1 at the bottom of the sleeve product.

[0017] This invention employs an ultra-thin conductive coating layer 1, which is suitable for achieving conductivity and shielding effects at low operating heights. The ultra-thin PI film substrate layer 2, combined with the conductive coating layer 1, can achieve a good compression recovery rate. The resulting sleeve-type integrated structure can compress to a lower position while retaining low resilience. Furthermore, since the PI film substrate layer 2 is heat-resistant and has stable performance, it is not prone to loss of elasticity under prolonged high temperature and humidity.

[0018] It should be noted that the present invention uses only one layer of conductive coating layer 1 and PI film substrate layer 2 for composite fixation. In practice, multiple layers of conductive coating layer 1 and PI film substrate layer 2 can be set as needed, and adjacent conductive coating layers 1 and PI film substrate layers 2 are compositely fixed by hot melt adhesive layer 3.

[0019] The height of the finished product of this invention can be designed arbitrarily, and can be more than twice the actual compression position, which can greatly compensate for gaps, and so on. Figure 4 As shown, the finished product of this invention can be compressed to a minimum height of 0.2mm, and the elastic force can be less than 0.8N; Furthermore, after 144 hours of compression at room temperature, the test sample was compressed to 0.3mm~0.4mm. At this point: Resistance < 0.2Ω, meets project requirements. Pressure <0.8N, meets project requirements; After 144 hours at 85℃ and 85% RH, the test sample was compressed to 0.3mm~0.4mm. At this point: Resistance <0.2Ω, meeting project requirements; The pressure is less than 0.8N, which meets the project requirements.

[0020] 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 implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0021] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A hollow conductive shielding buffer tubular component, characterized in that: It includes a conductive coating layer, a PI film substrate layer, and a hot melt adhesive layer; the hot melt adhesive layer is disposed between the conductive coating layer and the PI film substrate layer, the hot melt adhesive layer composites and fixes the conductive coating layer to the outer surface of the PI film substrate layer, and the conductive coating layer is coated on the outside of the PI film substrate layer by an overmolding method, the conductive coating layer and the PI film substrate layer together form a sleeve-type hollow structure.

2. The hollow conductive shielding buffer tubular component according to claim 1, characterized in that: The conductive coating layer is made of, but is not limited to, conductive cloth, conductive non-woven fabric, or conductive polyimide; the thickness of the conductive coating layer is not greater than 0.02 mm.

3. The hollow conductive shielding buffer tubular component according to claim 1, characterized in that: The thickness of the PI film substrate layer is no greater than 0.02 mm.

4. A hollow conductive shielding buffer tubular component according to claim 1, characterized in that: Conductive adhesive is uniformly applied to a pre-defined bonding area on the outside of the conductive coating layer, and the thickness of the conductive adhesive is 0.05mm~0.15mm.

5. A hollow conductive shielding buffer tubular component according to claim 1, characterized in that: The hot melt adhesive layer is an adhesive layer formed by curing a PET hot melt adhesive film, and the hot melt adhesive layer covers the bonding surface between the conductive wrapping layer and the PI film substrate layer.

6. A hollow conductive shielding buffer tubular component according to claim 1, characterized in that: The PI film substrate layer constitutes the inner support substrate of the sleeve, and the conductive wrapping layer constitutes the outer conductive layer of the sleeve; the conductive wrapping layer completely covers the outer peripheral surface of the PI film substrate layer.

7. A hollow conductive shielding buffer tubular component according to claim 1, characterized in that: The sleeve is an integrally formed structure; the sleeve wall is composed of the PI film substrate layer, the hot melt adhesive layer and the conductive coating layer stacked from the inside to the outside.

8. A method for preparing a hollow conductive shielding buffer tubular component, characterized in that: The processing steps include the following: S1. Select a hot melt adhesive film of a preset specification and use a die-cutting device to cut the hot melt adhesive film into a sheet that matches the bonding size of the conductive coating layer and the PI film substrate layer. S2. The hot melt adhesive film is completely filled into the gap between the conductive coating layer and the PI film substrate layer. The hot melt adhesive film is melted and solidified by hot pressing, so that the conductive coating layer and the PI film substrate layer are composite and fixed to obtain an integrated composite substrate. S3. Place the integrated composite substrate prepared in step S2 into a matching mold, and use the shaping structure of the mold to bend and shape the integrated composite substrate so that the conductive coating layer completely covers the outer surface of the PI film substrate. Then, shape and cure the substrate. Next, apply conductive adhesive evenly to the preset bonding area on the outside of the shaped and cured conductive coating layer, and after curing at room temperature, attach the release paper to form a sleeve-type integrated structure with the conductive coating layer covering the PI film substrate.

9. The method for preparing a hollow conductive shielding buffer tubular component according to claim 8, characterized in that: In step S2, the hot pressing temperature is 80℃~120℃, the hot pressing pressure is 0.2MPa~0.5MPa, and the hot pressing holding time is 3s~10s.

10. The method for preparing a hollow conductive shielding buffer tubular component according to claim 8, characterized in that: In step S3, after the coating and molding are completed, the sleeve structure is cured by room temperature air cooling, and the curing time is 5s~15s.

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