Multilayer flexible circuit board

Abstract

The invention discloses a multi-layer flexible circuit board, comprising at least two layers of circuit boards; adjacent layers of the circuit boards are bonded to each other by prepreg; the prepreg is provided with a through hole; one of the adjacent layers of the circuit boards is provided with a first glue-free area aligned to the through hole and a first glued area which is bonded to the prepreg; the other one of the adjacent layers of the circuit boards is provided with a second glue-free area aligned to the through hole and a second glued area which is bonded to the prepreg; the first glue-free area, the second glue-free area and the circumferential wall of the through hole enclose a chamber; the second glue-free area is provided with a ring of bulge which extends into the chamber; by the blocking function of the bulge, the volatile fog-typed prepreg can be prevented from flowing into the chamber, therefore, the delamination of adjacent layers of circuit boards is realized, the bending service life of the multi-layer flexible circuit board is prolonged, furthermore, as single delamination procedure is not needed to be arranged, the preparation flow is simplified, the working time is saved and the production cost is reduced.

Description

Technical field [0001] The invention relates to the field of circuit boards, in particular to a multilayer flexible circuit board. Background technique [0002] Multilayer flexible circuit boards are usually used in the field of flip mobile phones. The normal life of the mobile phone flip needs to reach more than 100,000 times. Therefore, the bending area of ​​the multi-layer flexible circuit board is designed as a single layer area during the design, that is, the bending area The area allows each layer of circuit boards to be separated in order to meet the bending life requirements of mobile phones. [0003] When the existing multilayer flexible circuit board is produced, it is formed by hot-pressing multiple circuit boards together through a thermosetting adhesive, and the bending area does not need to be glued, that is, there is a gap between the circuit boards of adjacent layers. Adhesive zone and adhesive-free zone, the multilayer flexible circuit board is disclosed in the C...

AI Technical Summary

Problems solved by technology

However, if the employees operate improperly, it is easy to cause wrinkles in the product. In addition, manual layering is also easy to miss the layering. For example, it should be divided into five layers but actually only divided into three layers, and there are two layers that have not been separated. Such a product If it flows into the customer's place, it will not meet the bending life requirements, which will have a fatal impact on the mobile phone; at the same time, manual rubbing and layering are time-consuming and laborious, increasing production man-hours, reducing efficiency and increasing costs.

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