Buffering foam

Abstract

The utility model discloses buffering foam, and relates to the technical field of foam. The buffer foam comprises a shielding layer, a first electrode and a second electrode, the wave absorbing layer is arranged on the shielding layer; and the bonding layer is arranged on one side, far away from the shielding layer, of the wave absorbing layer. According to the utility model, the problems that the outer wrapping material of the existing wrapping type foam is mostly made of a shielding or magnetism isolating material and cannot comprehensively resist electromagnetic interference, and the foam core is mostly made of a PU material, so that the temperature resistance effect is poor are solved.

Description

Technical Field

[0001] This utility model relates to the field of foam technology, and in particular to a cushioning foam. Background Technology

[0002] Currently, encapsulated foam, formed by wrapping different foaming materials with functional tapes, is widely used in the 3C electronics industry. Besides serving as a cushioning core, it also possesses other functionalities. Various sizes and even irregularly shaped foams can be designed and arranged according to different application needs. The existing wrapping process is very mature, the integrated structure of the encapsulated foam is very stable, its performance is excellent, and its aging resistance meets the requirements for long-term use.

[0003] In practical applications, encapsulated foam typically consists of an elastic material, such as PU or other foamed substances, in the middle. It primarily provides elastic cushioning. To enhance its functionality, special adhesive tape is wrapped around the foam, which can then provide shielding, thermal conductivity, or other functions.

[0004] Existing encapsulated foam materials are mostly shielding or magnetically insulating, which cannot fully resist electromagnetic interference. Furthermore, the foam core is often made of PU, resulting in poor temperature resistance. Currently, no effective solution has been proposed to address these issues. Utility Model Content

[0005] Purpose of the utility model: To provide a cushioning foam to at least solve one of the problems existing in the prior art.

[0006] Technical solution: An anti-electromagnetic interference film, comprising:

[0007] Shielding layer;

[0008] An absorbing layer is disposed on the shielding layer; and

[0009] An adhesive layer is disposed on the absorbing layer on the side away from the shielding layer;

[0010] The shielding layer and the absorbing layer are formed by hot pressing to create a composite functional film with both shielding and absorbing properties.

[0011] Preferably, the shielding layer is one of copper foil, nickel foil, aluminum foil, copper Mylar, or aluminum Mylar.

[0012] Preferably, the thickness of the adhesive layer is 25-50 μm.

[0013] To achieve the above objectives, according to another aspect of this application, a cushioning foam is also provided.

[0014] The cushioning foam according to this application includes the electromagnetic interference-resistant film as described above;

[0015] It also includes: a silicone foam core layer, the outer surface of which is covered with the anti-electromagnetic interference film along its axial direction, and the silicone foam core layer is connected to the adhesive layer.

[0016] Preferably, the silicone foam core layer has through holes along its axial direction.

[0017] Preferably, the through hole is circular or elliptical in shape.

[0018] Preferably, a conductive adhesive layer is provided on one side of the outer surface of the anti-electromagnetic interference film.

[0019] Preferably, the conductive adhesive layer is a conductive double-sided adhesive; the conductive double-sided adhesive is one of the following: substrate-free conductive double-sided adhesive, copper foil conductive double-sided adhesive, aluminum foil conductive double-sided adhesive, nickel foil conductive double-sided adhesive, or high-temperature resistant conductive cloth double-sided adhesive.

[0020] Preferably, a release layer is provided on the side of the conductive adhesive layer away from the electromagnetic interference-resistant film.

[0021] Preferably, the anti-electromagnetic interference film is in the form of a strip.

[0022] Beneficial effects: In this embodiment, a wrap-around composite anti-electromagnetic interference buffer foam is used. The shielding layer and the wave-absorbing layer are heat-pressed together to form a composite functional film with shielding and wave absorption functions. This achieves the purpose of composite shielding and wave absorption functions, thereby realizing the technical effects of excellent anti-electromagnetic interference, long-term high temperature resistance, solid overall structure, no delamination after long-term use, and good foam buffering effect. This solves the technical problems that the outer packaging material of existing wrap-around foam is mostly shielding or magnetic shielding material, which cannot comprehensively resist electromagnetic interference, and the foam core is mostly made of PU material, which results in poor temperature resistance. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the buffer foam structure of the application of the anti-electromagnetic interference film of this utility model.

[0024] The attached figures are labeled as follows:

[0025] 10. Shielding layer;

[0026] 20. Absorbing layer;

[0027] 30. Adhesive layer;

[0028] 40. Silicone foam core layer; 401. Through-hole;

[0029] 50. Conductive adhesive layer;

[0030] 60. Release layer. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0032] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0033] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this utility model based on the specific circumstances.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] like Figure 1 As shown, this application relates to cushioning foam. The electromagnetic interference suppression film includes: a shielding layer 10; the shielding layer 10 refers to a layer with signal shielding function, which can ensure good signal transmission effect.

[0036] It is important to know that the shielding layer 10 can prevent the propagation of invalid signals by reflecting electromagnetic waves.

[0037] The wave-absorbing layer 20 is disposed on the shielding layer 10; it can absorb a portion of electromagnetic waves, and the projected electromagnetic waves hit the shielding material and are then reflected back into its interior to form secondary absorption.

[0038] It is important to know that the material of the absorbing layer 20 will resonate with electromagnetic waves, converting the energy of the electromagnetic waves into heat energy, thereby reducing the intensity of the electromagnetic waves. The material design of this layer needs to control factors such as magnetism and dielectric loss to make it exhibit high absorption in the target frequency range.

[0039] Specifically, the preparation of the microwave absorbing material slurry can be carried out in ways including but not limited to the following:

[0040] I. Preparation of microwave absorbing material slurry:

[0041] 100 parts of polyurethane adhesive (solvent is one or two of cyclohexanone, butanone, toluene, and N,N-dimethyl ethylene glycol, with a solid content of 30-45%).

[0042] 150-250 parts of sheet-like magnetic powder (which may be one of iron-silicon-aluminum or iron-silicon-boron);

[0043] 0.1 to 5 parts dispersant;

[0044] The above mixture should be thoroughly stirred to form a microwave absorbing slurry.

[0045] II. Coating of microwave absorbing material:

[0046] At least four ovens are required, with a temperature range of 90~140℃. The release film is coated at a speed of 0.5~2M / min.

[0047] An adhesive layer 30 is disposed on the wave-absorbing layer 20 on the side away from the shielding layer 10; it can achieve a good bonding effect, thereby achieving structural stability; at the same time, it can also achieve a good fit with other components. Preferably, the adhesive layer 30 can be a high-adhesion silicone layer.

[0048] The shielding layer 10 and the absorbing layer 20 are formed by thermoforming to create a composite membrane with both shielding and absorbing properties. The thermoforming process ensures that the two layers are firmly bonded together under pressure and temperature, resulting in a structurally stable composite membrane.

[0049] The completed absorbing material is pressed (pressure set to 100~150kg) and heated (temperature set to 120~180℃) onto the metal surface of shielding materials such as copper foil, nickel foil, aluminum foil, copper Mylar, and aluminum Mylar to form a bond. The release film is then removed and the material is rolled up.

[0050] Hot-press bonding ensures close contact between the shielding layer 10 and the absorbing layer 20, reducing the interfacial air layer; at the same time, this process also ensures a reduction in the overall thickness of the composite film, making it suitable for large-scale production.

[0051] During the hot pressing process, precise temperature control is employed to prevent high temperatures from damaging the material properties of the shielding layer 10 and the absorbing layer 20. An appropriate temperature range ensures a strong bond at the material interfaces, preventing delamination or warping.

[0052] The composite functional membrane of this application has shielding and wave absorption properties that can effectively block, absorb and consume electromagnetic waves, and has a significant dual protection effect.

[0053] Electromagnetic shielding and wave absorption work together: shielding layer 10 reflects electromagnetic waves and wave absorbing layer 20 absorbs the remaining electromagnetic waves. The synergistic design ensures efficient electromagnetic interference protection and is suitable for environments with strict electromagnetic compatibility (EMC) requirements.

[0054] Flexibility and adaptability: Composite membranes are typically designed as flexible structures, suitable for applications on complex surfaces and curved structures, and can be adhered to irregular surfaces, thus expanding the range of applications.

[0055] Design flexibility of multi-layer structure: The shielding layer 10 and the absorbing layer 20 with different materials and thicknesses can be selected according to actual needs to meet the absorption requirements and electromagnetic shielding standards of specific frequency bands.

[0056] This application uses a shielding + absorbing structure to replace the traditional single-layer shielding or absorbing materials. The adhesive used for wrapping is also changed from traditional acrylic pressure-sensitive adhesive or hot melt adhesive to high-viscosity silicone pressure-sensitive adhesive. The foam core adopts a silicone open-pore structure to achieve a certain buffering effect.

[0057] As can be seen from the above description, this application achieves the following technical effects:

[0058] In this embodiment, a wrap-around composite anti-electromagnetic interference buffer foam is used. The shielding layer 10 and the wave-absorbing layer 20 are heat-pressed together to form a composite functional film with shielding and wave absorption functions. This achieves the purpose of composite shielding and wave absorption functions, thereby realizing the technical effects of excellent anti-electromagnetic interference, long-term high temperature resistance, solid overall structure, no delamination after long-term use, and good foam buffering effect. This solves the technical problems of existing wrap-around foams, where the outer packaging material is mostly shielding or magnetic shielding material, which cannot comprehensively resist electromagnetic interference, and the foam core is mostly made of PU material, resulting in poor temperature resistance.

[0059] Furthermore, the shielding layer 10 is one of copper foil, nickel foil, aluminum foil, copper Mylar, or aluminum Mylar. It is understood that this allows for the selection of multiple materials, enabling flexible use; simultaneously, all of the above materials possess excellent conductivity and electromagnetic shielding properties, effectively blocking and reflecting electromagnetic waves.

[0060] Furthermore, the thickness of the adhesive layer 30 is 25-50 μm. This allows for a variety of thicknesses to be selected while ensuring good interlayer bonding.

[0061] This application also relates to a cushioning foam, including the electromagnetic interference-resistant film as described above;

[0062] It also includes a silicone foam core layer 40, the outer surface of which is covered with the anti-electromagnetic interference film along its axial direction, and the silicone foam core layer 40 is connected to the adhesive layer 30. It is understood that by providing the silicone foam core layer 40, a good cushioning effect can be achieved; at the same time, a good interlayer fit can also be achieved.

[0063] It is important to know that the silicone foam core layer 40 plays a supporting and cushioning role in the entire structure, and has flexibility, high temperature resistance and shock absorption properties.

[0064] An anti-electromagnetic interference film is wrapped around the outer surface of the silicone foam core layer 40 along its axial direction, which can shield external electromagnetic interference. The anti-electromagnetic interference film is made of conductive materials (such as copper foil, nickel foil or aluminum foil, etc.) to form a shielding layer 10, which effectively blocks external electromagnetic waves.

[0065] Furthermore, the silicone foam core layer 40 has through holes 401 along its axial direction. This allows for good cooperation with other components; it also provides ventilation, exhaust, or functions for installation and fixation.

[0066] Furthermore, the through-hole 401 is circular or elliptical in shape. This is understood to further enhance the buffering or engagement effect.

[0067] Furthermore, a conductive adhesive layer 50 is provided on one side of the outer surface of the anti-electromagnetic interference film. It is understood that this achieves both effective adhesion and good conductivity.

[0068] Furthermore, the conductive adhesive layer 50 is a conductive double-sided adhesive; the conductive double-sided adhesive is one of the following: substrate-free conductive double-sided adhesive, copper foil conductive double-sided adhesive, aluminum foil conductive double-sided adhesive, nickel foil conductive double-sided adhesive, or high-temperature resistant conductive cloth double-sided adhesive. It is understood that the conductive adhesive layer 50 is an important component in the composite membrane structure for achieving conductive connection, shielding, and fixation; simultaneously, it allows for the selection of conductive double-sided adhesives of various materials. Preferably, the conductive adhesive layer 50 is a conductive double-sided adhesive; this facilitates easy implementation and operation.

[0069] Furthermore, a release layer 60 is provided on the side of the conductive adhesive layer 50 away from the electromagnetic interference-resistant film. It is understood that this provides good protection and also allows for easy removal when the composite film needs to be installed or adhered to a target surface, ensuring a smooth installation process without affecting the function of the conductive adhesive.

[0070] Furthermore, the electromagnetic interference (EMI) shielding film is strip-shaped. It is understood that by cutting the EMI shielding film into strips, a good fit with the silicone foam core layer 40 can be achieved.

[0071] Of course, the actual shape of the anti-electromagnetic interference film can be determined according to actual usage requirements, and is not limited in this application.

[0072] This utility model also has the following beneficial effects:

[0073] It has excellent electromagnetic interference resistance, shielding effectiveness of over 120dB (30M~1.5GHz), can withstand temperatures up to 150℃ for a long time, has a robust overall structure, does not delaminate after long-term use, has good foam cushioning effect, can be compressed up to 20%, has good resilience, good resistance to compression deformation (70℃ & 50%), and good conductivity.

[0074] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and all such equivalent transformations fall within the protection scope of the present invention.

Claims

1. A cushioning foam, characterized in that, Includes an electromagnetic interference (EMI) shielding film, the EMI shielding film comprising: Shielding layer (10); An absorbing layer (20) is disposed on the shielding layer (10); and An adhesive layer (30) is disposed on the absorbing layer (20) on the side away from the shielding layer (10); The shielding layer (10) and the absorbing layer (20) are formed by hot pressing to create a composite functional film with shielding and absorbing properties. It also includes: a silicone foam core layer (40), the outer surface of which is covered with the anti-electromagnetic interference film along its axial direction, and the silicone foam core layer (40) is connected to the adhesive layer (30); The silicone foam core layer (40) has through holes (401) along its axial direction; The anti-electromagnetic interference film is strip-shaped.

2. The cushioning foam according to claim 1, characterized in that, The through hole (401) is circular or elliptical in shape.

3. The cushioning foam according to claim 1, characterized in that, A conductive adhesive layer (50) is provided on one side of the outer surface of the anti-electromagnetic interference film.

4. The cushioning foam according to claim 3, characterized in that, The conductive adhesive layer (50) is a conductive double-sided adhesive; The conductive double-sided adhesive is one of the following: substrate-free conductive double-sided adhesive, copper foil conductive double-sided adhesive, aluminum foil conductive double-sided adhesive, nickel foil conductive double-sided adhesive, or high-temperature resistant conductive cloth double-sided adhesive.

5. The cushioning foam according to claim 3, characterized in that, A release layer (60) is provided on the side of the conductive adhesive layer (50) away from the electromagnetic interference film.

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