Electromagnetic wave shielding film

Abstract

Provided is an electromagnetic wave shielding film. The electromagnetic wave shielding film comprises a base material, a release layer, at least one insulating layer, a glass fiber layer, a conductiveadhesive layer and a protective film. The release layer is arranged on the surface of the base material; the insulating layer is arranged on the surface of the release layer; the glass fiber layer isarranged on the surface of the insulating layer; the conductive adhesive layer is arranged on the surface of the glass fiber layer; and then the surface of the glass fiber layer is coated with the protective film. Through the arrangement of the glass fiber layer, the dielectric constant (Dk) and the dielectric loss (Df) of the electromagnetic wave shielding film are obviously reduced, the insertion loss value is correspondingly reduced, and the requirement of 5G communication can be met.

Description

technical field [0001] The present disclosure relates to an electromagnetic wave shielding film for a flexible circuit board, in particular to an electromagnetic wave shielding film suitable for 5G. Background technique [0002] Since the beginning of the 21st century, with the advent of the information age, the FPC industry, which has gradually shifted from military use to civilian use, has ushered in great opportunities for development. It is widely used in consumer electronics such as computers, cameras, printers, and car audio. With the pursuit of light, thin, short, and small designs in consumer electronics products, the scope of FPC applications has been extended to new fields, including smart phones, PDAs, notebook computers, digital cameras, liquid crystal displays and other miniaturized terminal electronics. product. From the analysis of the development trend of the entire electronic product, future products tend to be thinner, lighter, highly integrated, and three...

AI Technical Summary

Problems solved by technology

This processing technology requires rigorous positioning operations to prevent errors in the mounting position of the electromagnetic wave protective film. Once the mounting position is wrong, the coating of the electromagnetic wave protective film is easily damaged when the electromagnetic wave protective film is peeled off, which affects the electromagnetic protection characteristics and the fault tolerance rate. It is relatively low, and the electromagnetic wave protective film after heating lamination and curing will be permanently mounted on the flexible circuit board, which cannot be repeatedly mounted and used. In addition, the known heating lamination curing process also has the following defects: (1) The operation is cumbersome and requires 2) The energy consumption is serious and the cost is high; (3) There are certain risks, such as high-temperature operation and high-temperature heating products that are toxic and harmful Substance etc.

[0017] Another example is the prior art: CN107592783A, which discloses an electromagnetic shielding film and its preparation method. The technical problem to be solved by this prior art is: at present, the shielding of the flexible circuit board must form a shielding film layer on its surface

[0019] First of all, the above-mentioned prior art naturally adopts different technical solutions to achieve their respective goals due to the different technical problems to be solved respectively; secondly, although the prior art: CN 106961826A and CN107592783A all relate to the structure of the electromagnetic shielding film, due to The structure of each electromagnetic shielding film has its own structure. The dielectric constant (Dk) and dielectric loss (Df) of the electromagnetic wave shielding film prepared by the existing technology are relatively large, and the product processing is applied to FPC (flexible circuit board) Finally, the insertion loss is large, which will affect the transmission of 5G signals

[0020] Secondly, although the prior art: CN 109370141A provides a thermosetting electronic composite material and the electronic composite material substrate prepared therefrom, the dissipation factor of the composite material substrate is low, and there is no obvious drift under high frequency and high temperature and high humidity conditions, and it is resistant to Good thermal properties, high peel strength, low water absorption, suitable for applications requiring high frequency such as antennas and base stations, but this prior art does not clearly record that it can be applied to the field of electromagnetic wave shielding film, even if it can be applied to this field, its The signal transmission performance is still not ideal, and it is not conducive to the transmission of 5G signals

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