Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film

Abstract

An embodiment of the present invention provides an electromagnetic shielding film, a circuit board and a preparation method of the electromagnetic shielding film, wherein the electromagnetic shieldingfilm comprises a first shielding layer, a second shielding layer, and an adhesive film layer. The first shielding layer is provided with a first through hole comprising a resin protrusion formed by solidifying resin flowing from one side to the other side for the first through hole. The second shielding layer is provided on one side of the first shielding layer near the resin protrusion and covered on the resin protrusion, thereby forming a raised portion on the outer surface of the second shielding layer corresponding to the resin protrusion. The adhesive film layer is provided on one side of the second shielding layer away from the first shielding layer, and the raised portion extends into the adhesive film layer, so that the raised portion ensures that the second shielding layer can pierce the adhesive film layer smoothly and contact a ground layer of the circuit board during pressing process, thereby ensuring normal expert of interference charges and achieving shielding function.

Description

technical field [0001] The invention relates to the field of electronics, in particular to an electromagnetic shielding film, a circuit board and a preparation method of the electromagnetic shielding film. Background technique [0002] With the rapid development of the electronics industry, electronic products are further developed toward miniaturization, light weight, and high-density assembly, which greatly promotes the development of flexible circuit boards, thereby realizing the integration of component devices and wire connections. Flexible circuit boards can be widely used in industries such as mobile phones, liquid crystal displays, communications and aerospace. [0003] Driven by the international market, functional flexible circuit boards dominate the flexible circuit board market, and an important indicator for evaluating the performance of functional flexible circuit boards is electromagnetic shielding (Electromagnetic Interference Shielding, referred to as EMI Sh...

AI Technical Summary

Problems solved by technology

However, at high temperature, due to the expansion of the conductive adhesive layer, the conductive particles in the conductive adhesive layer that were originally in contact with each other or the conductive particles that were originally in contact with the circuit board ground layer were pulled apart, resulting in grounding failure, and the interference charge could not be quickly exported. , the shielding function cannot be realized

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