阅读说明：本技术 一种解决电磁屏蔽型刚挠结合板大批量生产的制作方法 (Manufacturing method for solving mass production of electromagnetic shielding type rigid-flex printed circuit board ) 是由 潘宇翔 陈世金 韩志伟 徐缓 陈苑明 张胜涛 王守绪 于 2019-10-11 设计创作，主要内容包括：本发明公开了一种解决电磁屏蔽型刚挠结合板大批量生产的制作方法,涉及电路板制造的技术领域,解决了保护膜难以从电磁波屏蔽膜上撕下的技术问题。该方法包括挠性芯板制作步骤、低流动半固化片制作步骤、刚性芯板制作步骤、叠层压合成步骤和揭盖步骤,所述刚性芯板制作步骤包括：在所述刚性芯板的揭盖区上设置一保护膜；在所述叠层压合成步骤,所述保护膜完全覆盖挠性芯板上的电磁波屏蔽膜。本发明实用性强、生产高效、成本低下,在揭盖时可轻易的与电磁波屏蔽膜进行剥离,且在制作电磁屏蔽型刚挠接合板时可对电磁波屏蔽膜进行有效的保护；还能适用于各种结构的电磁波屏蔽膜类刚挠结合板进行大批量生产。(The invention discloses a manufacturing method for solving the problem of large-scale production of electromagnetic shielding type rigid-flex printed circuit boards, relates to the technical field of circuit board manufacturing, and solves the technical problem that a protective film is difficult to tear off from an electromagnetic wave shielding film. The method comprises a flexible core board manufacturing step, a low-flow prepreg manufacturing step, a rigid core board manufacturing step, a lamination synthesis step and a cover uncovering step, wherein the rigid core board manufacturing step comprises the following steps: arranging a protective film on the uncovering area of the rigid core plate; in the lamination step, the protective film completely covers the electromagnetic wave shielding film on the flexible core board. The invention has strong practicability, high production efficiency and low cost, can be easily stripped from the electromagnetic wave shielding film when the cover is uncovered, and can effectively protect the electromagnetic wave shielding film when the electromagnetic shielding rigid-flex joint plate is manufactured; and the method is also suitable for mass production of electromagnetic wave shielding film rigid-flex printed boards with various structures.)

1. A manufacturing method for solving the problem of mass production of electromagnetic shielding type rigid-flex printed boards comprises a flexible core board manufacturing step, a low-flow prepreg manufacturing step, a rigid core board manufacturing step, a lamination and lamination synthesis step and a cover uncovering step, and is characterized in that the rigid core board manufacturing step comprises: arranging a protective film (6) on the uncovering area of the rigid core plate (5); in the lamination step, the protective film (6) completely covers the electromagnetic wave shielding film (3) on the flexible core board (1).

2. The manufacturing method for solving the mass production of the electromagnetic shielding type rigid-flex printed circuit board according to claim 1, wherein both sides of the protective film (6) are 0.3-1mm longer than both sides of the electromagnetic wave shielding film (3); both ends of the protective film (6) are 0.5-1mm longer than both ends of the electromagnetic wave shielding film (3).

3. The manufacturing method for solving the problem of mass production of the electromagnetic shielding type rigid-flex printed circuit board according to claim 2, wherein the protective film (6) is a protective copper sheet, and the protective copper sheet is manufactured when the circuit of the rigid core board (5) is etched.

4. The manufacturing method for solving the mass production problem of the electromagnetic shielding type rigid-flex printed circuit board according to claim 1 is characterized by comprising the following steps:

s1, the manufacturing steps of the flexible core board comprise: adhering a covering film (2) on the surface of the pure dynamic flexible bending area of the flexible core board (1), and adhering an electromagnetic wave shielding film (3) on the covering film (2);

the manufacturing steps of the low-flow prepreg comprise: windowing and hollowing are carried out on the region of the pure dynamic flexible bending region corresponding to the low-flow prepreg (4);

the manufacturing steps of the rigid core plate further comprise: marking a cover uncovering area corresponding to the pure dynamic flexible bending area on the rigid core plate (5);

s2, the lamination and synthesis step comprises the following steps: sequentially laminating the windowed and hollowed low-flow prepreg (4) and the rigid core board (5) with the protective film (6) and the cover uncovering area on the flexible core board (1) with the cover film (2) and the electromagnetic wave shielding film (3) in sequence for pressing;

s3, the uncovering step comprises the following steps: and uncovering the covered area on the rigid core plate (5) after pressing.

5. A manufacturing method for solving the problem of mass production of the electromagnetic shielding type rigid-flex printed circuit board according to claim 4, wherein a uncovering area is divided on the rigid core plate (5) through a blind groove (7), and the depth of the blind groove (7) is 1/3-1/2 of the thickness of the rigid core plate (5).

6. The manufacturing method for solving the problem of mass production of the electromagnetic shielding type rigid-flex printed circuit board according to claim 5, wherein after the blind groove (7) is manufactured on the rigid core plate (5), the rigid core plate (5) is subjected to plasma cleaning.

7. The method for manufacturing the rigid-flex printed circuit board with electromagnetic shielding in mass production according to claim 4, wherein in the step of manufacturing the flexible core board, the flexible core board (1) is subjected to plasma cleaning before the flexible core board (1) is pressed against the cover film (2).

Technical Field

The invention relates to the technical field of circuit board manufacturing, in particular to a manufacturing method for solving the problem of mass production of electromagnetic shielding type rigid-flex printed circuit boards.

Background

With the increasing complexity of the circuit design of the rigid-flex circuit board, the number of used components is increasing, the noise generated between the internal circuit and the components and the external electromagnetic sound are more and more serious, and the electromagnetic interference formed between the internal circuit and the components seriously affects the signal transmission. In order to shield the electromagnetic radiation interference and ensure the integrity of the signal transmission of the product, a consensus has been formed in the industry for a long time, namely that an electromagnetic wave shielding film is attached to a pure dynamic flexible bending area of a rigid-flex circuit board to solve the problem. Aiming at the electromagnetic shielding type flex-rigid circuit board, two production methods are mainly adopted in the industry to realize the attachment of the electromagnetic wave shielding film on the pure dynamic flexible bending area of the flex-rigid circuit board, and the method and the corresponding defects are summarized as follows:

(1) the process has the biggest defects that ① electromagnetic wave shielding films can only be attached to the inner layer of the cover milling window single-piece pure dynamic flexible bending area covering film, the attaching operation efficiency is low, and the feasibility of mass production is not provided, after ② electromagnetic wave shielding films are attached, as the rigid-flexible combining area and the pure dynamic flexible bending area of the electromagnetic wave shielding films attached to the cover milling window have larger step height difference, a special convex jig is required for pressing, the cost of the special jig is high, and the production pressing is not easy to control.

(2) ① when the flexible plate adhered with the electromagnetic wave shielding film is subjected to total pressure with an outer rigid plate and middle non-flowing PP, the PET protective film on the outer layer of the electromagnetic wave shielding film is easy to embrittle at high temperature and high pressure, and the condition that the PET protective film on the outer layer of the electromagnetic wave shielding film cannot be torn off and scrapped occurs, if the PET protective film is torn off and pressed in advance, the FR4 rigid plate is partially adhered to the insulating layer of the electromagnetic wave shielding film under high pressure, and the appearance and the performance of the electromagnetic wave shielding film are damaged after uncovering, ② when the cover film is pre-adhered to the rigid plate corresponding to the position of the adhered electromagnetic wave shielding film for pressing protection in the industry, the method can realize separation of a window of the cover from the electromagnetic wave shielding film, but the cover film adhered to the rigid plate is still required to be subjected to quick pressing after adhering, so that the total pressure of the PP adhered with the middle non-flowing PP and the flexible plate adhered with the electromagnetic wave shielding film can still be produced in large scale, and the feasibility is still low.

Disclosure of Invention

The invention aims to solve the technical problem of the prior art, and provides a manufacturing method for mass production of electromagnetic shielding type rigid-flex printed circuit boards, which can be easily peeled from an electromagnetic shielding film when a cover is uncovered.

The technical scheme of the invention is as follows: a manufacturing method for solving the problem of mass production of electromagnetic shielding type rigid-flex printed boards comprises a flexible core board manufacturing step, a low-flow prepreg manufacturing step, a rigid core board manufacturing step, a lamination and lamination synthesis step and a cover uncovering step, wherein the rigid core board manufacturing step comprises the following steps: arranging a protective film on the uncovering area of the rigid core plate; in the lamination step, the protective film completely covers the electromagnetic wave shielding film on the flexible core board.

The two sides of the protective film are 0.3-1mm longer than the two sides of the electromagnetic wave shielding film; both ends of the protective film are 0.5-1mm longer than both ends of the electromagnetic wave shielding film.

Furthermore, the protective film is a protective copper sheet, and the manufacturing method of the protective copper sheet is to manufacture the protective copper sheet when the circuit of the rigid core board is etched.

Further, the method comprises the steps of:

s1, the manufacturing steps of the flexible core board comprise: sticking a covering film on the surface of the pure dynamic flexible bending area of the flexible core board, and sticking an electromagnetic wave shielding film on the covering film;

the manufacturing steps of the low-flow prepreg comprise: windowing and hollowing out the area of the pure dynamic flexible bending area corresponding to the low-flow prepreg;

the manufacturing steps of the rigid core plate further comprise: marking a cover uncovering area corresponding to the pure dynamic flexible bending area on the rigid core plate;

s2, the lamination and synthesis step comprises the following steps: sequentially laminating the windowed and hollowed low-flow prepreg and the rigid core plate with the protective film and the cover uncovering area on the flexible core plate with the cover film and the electromagnetic wave shielding film for pressing;

s3, the uncovering step comprises the following steps: and uncovering the uncovering area on the pressed rigid core board.

Further, a cover-removing region is formed on the rigid core plate by blind grooves, and the depth of the blind grooves is 1/3-1/2 of the thickness of the rigid core plate.

Furthermore, after the blind groove is manufactured on the rigid core plate, the rigid core plate is subjected to plasma cleaning.

Furthermore, in the flexible core board manufacturing step, before the flexible core board is attached to the covering film, the flexible core board is subjected to plasma cleaning.

Advantageous effects

The invention has the advantages that: the protective film is arranged at the cover uncovering area on the rigid core plate, so that the electromagnetic wave shielding film is protected in the laminating process of the rigid-flex printed circuit board, and the rigid-flex printed circuit board can be easily peeled from the electromagnetic wave shielding film when the cover is uncovered, and the required rigid-flex printed circuit board containing the electromagnetic wave shielding film is obtained. The method avoids the problem that the protective film is difficult to tear off when being directly adhered to the electromagnetic wave shielding film, greatly improves the reliability when the rigid-flex joint plate is manufactured, and has lower production cost and higher production efficiency. The blind holes are utilized to mark the uncovering areas corresponding to the pure dynamic flexible bending areas on the rigid core plate, so that the uncovering areas can be effectively positioned while the connection strength between the rigid core plate and the uncovering areas on the rigid core plate is not influenced, and the uncovering is convenient.

Drawings

FIG. 1 is a schematic structural view of a flexible core board of the present invention after lamination;

FIG. 2 is a schematic structural view of the low-flow prepreg after windowing and hollowing;

FIG. 3 is a schematic view of a rigid core panel of the present invention;

FIG. 4 is a schematic structural diagram of an electromagnetic shielding rigid-flex printed circuit board laminated by a flexible core board, a low-flow prepreg and a rigid core board according to the present invention;

fig. 5 is a schematic structural diagram of a finished product of the electromagnetic shielding type rigid-flex printed circuit board of the present invention.

Wherein: 1-flexible core board, 2-covering film, 3-electromagnetic wave shielding film, 4-low flow prepreg, 5-rigid core board, 6-protective film and 7-blind groove.

Detailed Description

The invention is further described below with reference to examples, but not to be construed as being limited thereto, and any number of modifications which can be made by anyone within the scope of the claims are also within the scope of the claims.

Referring to fig. 1 to 5, the manufacturing method for solving the problem of mass production of the electromagnetic shielding type rigid-flex printed circuit board according to the present invention includes a flexible core board manufacturing step, a low flow prepreg manufacturing step, a rigid core board manufacturing step, a lamination and lamination step, and a cover uncovering step. Wherein, the rigid core plate manufacturing step includes: a protective film 6 is arranged on the uncovering area of the rigid core plate 5. In the lamination step, the protective film 6 completely covers the electromagnetic wave-shielding film 3 on the flexible core board 1. Because the protective film 6 is adhered to the rigid core board 5, the protective film 6 is not adhered to the electromagnetic wave shielding film 3 when the cover is removed, and the rigid core board 5 and the electromagnetic wave shielding film 3 can be easily peeled off to obtain the required electromagnetic shielding type rigid-flexible combined board containing the electromagnetic wave shielding film 3. In this embodiment, the rigid core board 5 is an FR-4 circuit board. Specifically, both sides of the protective film 6 are 0.3 to 1mm longer than both sides of the electromagnetic wave shielding film 3; both ends of the protective film 6 are 0.5 to 1mm longer than both ends of the electromagnetic wave-shielding film 3. The protective film 6 is only slightly larger than the electromagnetic wave shielding film 3, so that the electromagnetic wave shielding film 3 is effectively covered, other laminated layers are not affected in the pressing process, the reliability is high, and the practicability is high. Preferably, the protective film 6 is a protective copper sheet, and the protective copper sheet is formed by etching the circuit of the rigid core 5. Specifically, before the circuit is manufactured, the circuit on the rigid core board 5 is optimized through CAM software, and corresponding protective copper sheets are reserved. After the rigid core plate 5 is etched, the corresponding protective copper sheet is reserved on the cover removing area of the rigid core plate 5, so that the protective film 6 is directly manufactured, and the protective film 6 does not need to be adhered on the rigid core plate 5. Compared with the prior art, the manufacturing process is simpler, the problem that the electromagnetic wave shielding film 3 can be pressed by means of a special pressing jig when the process of firstly milling the cover in the cover removing area and then sticking the electromagnetic wave shielding film 3 can be solved, and the problems of high production cost, difficult production operation and low production efficiency are solved. Meanwhile, the problem of low production efficiency in the process of protecting the electromagnetic wave shielding film 3 in the pressing process by attaching the cover film 2 on the rigid core plate 5 can be solved.

In conclusion, the electromagnetic shielding type rigid-flex printed circuit board has the advantages of lower production cost and higher production efficiency, the difficulty in mass production and manufacturing of the electromagnetic shielding type rigid-flex printed circuit board is solved, and the mass produced electromagnetic shielding type rigid-flex printed circuit board has higher quality and higher qualification rate than products produced by the prior art.

The manufacturing method comprises the following steps:

s1, the manufacturing steps of the flexible core board comprise: sticking a covering film 2 on the surface of the pure dynamic flexible bending area of the flexible core board 1, and sticking an electromagnetic wave shielding film 3 on the covering film 2;

the manufacturing steps of the low-flow prepreg comprise: windowing and hollowing are carried out on the region of the pure dynamic flexible bending region corresponding to the low-flow prepreg 4;

the manufacturing steps of the rigid core plate further comprise: the rigid core plate 5 is scribed with a uncovering area corresponding to the purely dynamic flexible bending area.

S2, the lamination and synthesis step comprises: and sequentially laminating the windowed and hollowed low-flow prepreg 4 and the rigid core board 5 with the protective film 6 and the uncovered area on the flexible core board 1 with the covering film 2 and the electromagnetic wave shielding film 3 for lamination.

S3, the cover uncovering step comprises the following steps: and uncovering the uncovering area on the pressed rigid core plate 5.

In this embodiment, the rigid core 5 is divided into uncovering areas by blind slots 7. The blind slot 7 is grooved by laser grooving or electric milling, and the specific grooving tool is selected according to the thickness of the rigid core plate 5. In the process of pressing the rigid-flex combined plate, the pressing force on the rigid-flex combined plate is large. In order to avoid the situation that the area of the pure dynamic flexible bending area marked on the rigid core plate 5 is broken and separated in the pressing process, the blind groove 7 is arranged on the rigid core plate 5, so that the area of the pure dynamic flexible bending area on the rigid core plate 5 can be effectively positioned while the connection strength of the rigid core plate 5 and the cover removing area on the rigid core plate is not influenced, and the cover is better removed. Preferably, the blind recesses 7 have a depth 1/3-1/2 of the thickness of the rigid core 5.

After the blind groove 7 is formed in the rigid core plate 5, the rigid core plate 5 is plasma-cleaned. After the blind groove 7 is formed on the rigid core plate 5, a certain amount of waste and dust with static electricity are attached to the surface of the rigid core plate and the blind groove 7. Therefore, the rigid core plate 5 needs to be plasma-cleaned, so that the surface cleanness of the rigid core plate 5 and the protective copper sheet is ensured, and the protective copper sheet is prevented from being oxidized. In the manufacturing step of the flexible core board, before the flexible core board 1 is attached to the covering film 2, the flexible core board 1 is subjected to plasma cleaning, so that the influence of dust on the flexible core board 1 on the attachment of the covering film 2 is avoided, and the attachment is more reliable.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various changes and modifications without departing from the structure of the invention, which will not affect the effect of the invention and the practicability of the patent.