Flexible circuit board product and method of making the same

Abstract

The application discloses a flexible circuit board product and a preparation method thereof. The preparation method comprises the following steps: obtaining a flexible circuit board layout, a first bearing film and a second bearing film, the flexible circuit board layout being provided with a first area, a die cutting area, a second area and a first die positioning hole, the first area and the second area being arranged on opposite sides of the die cutting area, and the first die positioning hole being located in the die cutting area; the first bearing film is correspondingly attached to the first area, and the second bearing film is correspondingly attached to the second area, so as to obtain a first product intermediate body; and the first product intermediate body is subjected to a die cutting forming operation based on the first die positioning hole, so as to obtain the flexible circuit board product. The first die positioning hole for die cutting forming positioning on the die cutting area is directly exposed outside the coverage range of the first bearing film and the second bearing film, so that it is unnecessary to design a windowed hollow avoidance of the die cutting area, and the processing cycle of the auxiliary material is greatly shortened, and the processing flow is simplified.

Description

Technical Field

[0001] This invention relates to the field of circuit board technology, and in particular to a flexible circuit board product and its manufacturing method. Background Technology

[0002] Flexible circuit boards are flexible printed circuit boards made of polyimide or polyester film as substrate. They are characterized by high wiring density, light weight, thinness and good bending ability, and are widely used in aerospace, military, mobile communications, computer peripherals and digital cameras.

[0003] In the back-end manufacturing process of flexible circuit boards, micro-adhesive carrier films are typically used as auxiliary materials to fix the flexible circuit board panel during punching and to serve as the carrier for shipping packaging after punching. However, existing carrier films require multiple processes such as cutting, drilling, and die punching to create windows in the corresponding die-cutting area to achieve the window cutout design, which results in a cumbersome processing flow. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a flexible circuit board product and its preparation method, which can effectively simplify the processing and preparation process of flexible circuit board products.

[0005] In a first aspect, the present invention provides a method for manufacturing a flexible circuit board product. The manufacturing method includes: A flexible circuit board panel, a first carrier film, and a second carrier film are obtained; wherein, the flexible circuit board panel has a first region, a die-cutting region, a second region, and a first die positioning hole, the first region and the second region are disposed on opposite sides of the die-cutting region, and the first die positioning hole is located in the die-cutting region; The first carrier film is attached to the first region, and the second carrier film is attached to the second region to obtain the first product intermediate. The first product intermediate is punched and formed based on the positioning hole of the first mold to obtain a flexible circuit board product.

[0006] In one implementation of the first aspect, attaching the first carrier film to the first region and attaching the second carrier film to the second region includes: A first positioning reference is determined, and the first carrier film is correspondingly attached to the first area based on the first positioning reference; wherein, the first positioning reference includes a plurality of first marking lines disposed at the edge of the first area; A second positioning reference is determined, and the second carrier film is correspondingly attached to the second region based on the second positioning reference; wherein, the second positioning reference includes a plurality of second marking lines disposed at the edge of the second region.

[0007] In one implementation of the first aspect, the punching and forming operation of the first product intermediate based on the first mold positioning hole includes: The first product intermediate is punched and formed based on the positioning hole of the first mold. After the die-cutting process is completed, the corresponding waste material is removed to obtain the second product intermediate.

[0008] In one implementation of the first aspect, punching the first product intermediate body based on the first mold positioning hole includes: The first product intermediate is placed on the punch press of the hardware steel mold. Positioning is performed based on the positioning hole of the first mold, and the intermediate body of the first product is punched and formed by the hardware steel mold. The cutting edge of the metal steel mold is provided with an anti-stick coating, which is a diamond-like carbon coating or a chromium nitride coating.

[0009] In one implementation of the first aspect, after removing the corresponding waste to obtain the second product intermediate, the method further includes: performing FQC inspection on the second product intermediate, and using the qualified second product intermediate as the flexible circuit board product.

[0010] In one implementation of the first aspect, before performing the punching and forming operation on the first product intermediate based on the first mold positioning hole, the method further includes: performing a dummy pressing process on the first product intermediate.

[0011] In one implementation of the first aspect, the flexible circuit board panel further includes a third region and a fourth region, both of which are provided with gold finger pads and second mold positioning holes. The third region is connected to the first region and located on the side of the first region away from the second region, and the fourth region is connected to the second region and located on the side of the second region away from the first region.

[0012] In one implementation of the first aspect, the carrier film includes a polyester film layer and an adhesive layer, wherein the thickness of the polyester film layer is 50 μm to 60 μm and the thickness of the adhesive layer is 10 μm to 25 μm.

[0013] In one implementation of the first aspect, the number of the first mold positioning holes is multiple, and the maximum distribution width of the multiple first mold positioning holes along the first direction is less than or equal to the width of the mold punching area in the first direction.

[0014] Secondly, the present invention provides a flexible circuit board product. The flexible circuit board product is obtained by the preparation method described above. The flexible circuit board product includes a first carrier film, a second carrier film, and a plurality of flexible circuit boards. The first carrier film and the second carrier film are arranged side-by-side along a first direction with a gap between them. The plurality of flexible circuit boards are arranged in an array along a second direction on the first carrier film and the second carrier film, and each flexible circuit board is partially attached to the first carrier film and partially attached to the second carrier film; wherein the first direction is perpendicular to the second direction.

[0015] The beneficial effects of this invention are as follows: by defining a first region and a second region on both sides of the die-cutting area, and further optimizing the integral irregularly shaped carrier film that requires drilling and window opening into a first carrier film and a second carrier film, and attaching the first carrier film and the second carrier film to the first region and the second region of the flexible circuit board panel respectively, the die-cutting area (i.e., the first die positioning hole used for subsequent die-cutting and forming positioning) is directly exposed outside the coverage area of ​​the first carrier film and the second carrier film.

[0016] Based on this, flexible circuit board products can be obtained by directly performing punching and forming operations based on the positioning holes of the first mold exposed in the space without the support film. This eliminates the need for drilling and die punching to create openings or cutouts in the die-cutting area of ​​the support film, significantly shortening the auxiliary material processing cycle, simplifying the processing flow, and reducing processing costs. Furthermore, since neither the first nor the second support film has any openings or cutouts, they are subjected to uniform stress during punching, thus avoiding the quality risks associated with openings or cutouts from the design stage. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the carrier membrane (i.e., the third carrier membrane) in the related technology.

[0018] Figure 2 This is a schematic diagram of the structure of the flexible circuit board panel and the carrier film (i.e., the third carrier film) in the bonded state.

[0019] Figure 3 This is a flowchart of the steps in a method for manufacturing a flexible circuit board product according to an embodiment of the present invention.

[0020] Figure 4This is a schematic diagram of the structure of the first carrier membrane and the second carrier membrane disclosed in an embodiment of the present invention.

[0021] Figure 5 This is a schematic diagram of the structure of a flexible circuit board panel disclosed in an embodiment of the present invention.

[0022] Figure 6 This is a schematic diagram of the flexible circuit board panel, the first carrier film, and the second carrier film in a bonded state, as disclosed in an embodiment of the present invention.

[0023] Figure 7 This is a structural schematic diagram of a flexible circuit board product disclosed in an embodiment of the present invention.

[0024] Label Explanation: 1. Flexible circuit board panelization; 11. First area; 12. Die punching area; 121. First die positioning hole; 13. Second area; 14. Third area; 15. Fourth area; 16. Second die positioning hole; 17. First marking line; 18. Second marking line; 19. Punched structure; 2. First carrier membrane; 21. First punched groove; 3. Second carrier membrane; 31. Second punching groove; 4. Flexible circuit board products; 41. Flexible circuit board; 42. Gold fingers; 5. Third bearing membrane; 6. Window structure. Detailed Implementation

[0025] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0026] To facilitate understanding of the technical solutions provided in the embodiments of the present invention by those skilled in the art, the relevant technologies are described below: Flexible circuit boards are printed circuit boards made of polyimide or polyester film as the substrate. They are highly reliable and extremely flexible, characterized by high wiring density, light weight, thinness and good bending ability. They are widely used in aerospace, military, mobile communications, computer peripherals and digital cameras.

[0027] In the back-end manufacturing process of flexible circuit boards, micro-adhesive carrier films are typically used as auxiliary materials to fix the flexible circuit board assembly during die-cutting and to serve as the carrier for shipping packaging after die-cutting. Related technologies, such as... Figure 1 as well as Figure 2As shown, the carrier film (i.e., the third carrier film 5 in the following figures) needs to undergo multiple processes such as cutting, drilling, and die punching to create openings and slots, in order to design openings and slots to avoid gaps in the corresponding flexible circuit board gold finger pads (on which gold fingers are located) and the die punching area (i.e., the secondary die punching area), thereby forming an opening structure 6 with gap holes and gap grooves. However, the above design and processing method has the following drawbacks: (1) The processing flow of carrier film auxiliary materials is complicated. The aforementioned window-opening and hollow-out design requires specialized molds for punching and cutting, resulting in complex processes, high costs, and long cycles.

[0028] (2) The design of opening windows and hollowing out to avoid space introduces potential quality hazards. The perforated areas on the carrier film are prone to stress concentration during punching, and the edges of the perforations may experience adhesive peeling or fuzzing during punching, affecting product quality.

[0029] (3) The bonding process relies on fixtures, resulting in low efficiency. When bonding continuous carrier films with perforated designs such as relief holes and relief grooves, a fixture is needed to align and bond them with the flexible circuit board panel. This method relies on the precision of the fixture, is cumbersome, and misalignment may cause the die to press against the edge of the carrier film during subsequent punching, resulting in problems such as fuzz or adhesive residue sticking to the gold finger pads.

[0030] (4) The alignment accuracy requirements between the clearance hole and the positioning hole are stringent. The clearance holes on the carrier film need to be precisely aligned with the mold positioning holes on the flexible circuit board panel. Any slight deviation may cause the punching die to press against the carrier film, resulting in fuzz or residual adhesive. This alignment requirement significantly increases the bonding difficulty and defect rate.

[0031] (5) Low utilization rate of carrier membrane material In conventional designs, the carrier film uses a single, continuous sheet structure, with its bonding area completely covering the entire area of ​​the flexible circuit board panel. Because the carrier film needs to be perforated to avoid the gold fingers and secondary die-cutting areas, it inevitably generates a large amount of unusable waste material, resulting in a significantly low material utilization rate.

[0032] To at least address the aforementioned problems, this invention provides a manufacturing solution for flexible circuit board products. In this solution, by fully exposing the first mold positioning hole 121 on the die-cutting area 12 to the space uncovered by the carrier film, subsequent die-cutting operations can be performed directly based on this fully exposed first mold positioning hole 121. Based on this, the carrier film, as an auxiliary material, only needs to be cut, eliminating the need for drilling and die-cutting window / cutting designs, effectively simplifying the carrier film auxiliary material processing and bonding process. Simultaneously, this solution fundamentally reduces the risk of fuzz and residual adhesive caused by traditional window / cutting designs (such as avoidance holes), while simultaneously considering the dual functions of carrier film die-cutting assistance and packaging support. It is suitable for the later stages of FPC die-cutting and packaging, demonstrating good industrial applicability.

[0033] The technical solutions according to the present invention will be described below with reference to specific embodiments and in conjunction with the accompanying drawings.

[0034] Figure 3 This is a flowchart illustrating the steps of a method for manufacturing a flexible circuit board product according to an embodiment of the present invention. (Refer to...) Figure 3 The preparation method includes the following steps 100 to 104.

[0035] Step 100: Obtain the flexible circuit board panel 1, the first carrier film 2, and the second carrier film 3; wherein, the flexible circuit board panel 1 has a first region 11, a die-cutting region 12, a second region 13, and a first die positioning hole 121, the first region 11 and the second region 13 are disposed on opposite sides of the die-cutting region 12, and the first die positioning hole 121 is located in the die-cutting region 12; Step 102: The first carrier film 2 is attached to the first region 11, and the second carrier film 3 is attached to the second region 13 to obtain the first product intermediate. Step 104: Perform a punching and forming operation on the first product intermediate body based on the first mold positioning hole 121 to obtain the flexible circuit board product 4.

[0036] As can be seen from the above description, the beneficial effects of the present invention are as follows: by defining a first region 11 and a second region 13 on both sides of the die-cutting area 12, and further optimizing the integral irregularly shaped carrier film that needs to be drilled and perforated into a first carrier film 2 and a second carrier film 3, and attaching the first carrier film 2 and the second carrier film 3 to the first region 11 and the second region 13 of the flexible circuit board panel 1 respectively, the die-cutting area 12 (that is, the first die positioning hole 121 used for subsequent die-cutting and forming positioning) is directly exposed outside the coverage area of ​​the first carrier film 2 and the second carrier film 3.

[0037] Based on this, the corresponding flexible circuit board product 4 can be obtained by directly performing the corresponding punching and forming operation based on the first mold positioning hole 121 exposed in the space without the support film coverage. This eliminates the need for drilling and mold punching to create openings and cutouts in the mold punching area 12 of the support film, significantly shortening the auxiliary material processing cycle, simplifying the processing flow, and reducing processing costs. At the same time, since the first support film 2 and the second support film 3 do not have any opening or cutout structures, the first support film 2 and the second support film 3 are subjected to uniform force during punching, thus avoiding the quality risks caused by opening or cutout designs from the design source.

[0038] The following combination Figure 3 The steps in steps 100 to 104, as well as other optional steps, are described in detail.

[0039] Step 100: Obtain the flexible circuit board panel 1, the first carrier film 2, and the second carrier film 3; wherein, the flexible circuit board panel 1 has a first region 11, a die-cutting region 12, a second region 13, and a first die positioning hole 121, the first region 11 and the second region 13 are disposed on opposite sides of the die-cutting region 12, and the first die positioning hole 121 is located in the die-cutting region 12.

[0040] It should be noted that the flexible circuit board panel 1 (i.e., FPC panel) of the present invention is in a continuous state, and it is an FPC panel that has undergone the first punching and forming process, such as... Figure 5 As shown, the FPC panel has a punched structure 19 (such as a punched hole) formed in the first punching process. Based on this, the present invention mainly optimizes and adjusts the second punching process. That is, the flexible circuit board product obtained by the present invention requires two punching processes. The first punching process is a partial pre-punching, in which only the outline of the product needs to be formed locally on the flexible circuit board panel, without completely separating the flexible circuit boards. For example, it can be used for the plug-in gold finger part with PI reinforcement, which needs to be pre-formed in the connected state of the panel. During and after the first punching process, the product remains in a connected state, so there is no need to attach a carrier film. On this basis, the first carrier film and the second carrier film are attached to the FPC panel to perform the second punching process, thereby completely punching the FPC panel into a single flexible circuit board, and using the first carrier film and the second carrier film to fix the array arrangement of multiple flexible circuit boards in the product for packaging and shipping.

[0041] To facilitate understanding of the accompanying drawings and differentiation of the corresponding structures, in Figure 2 , Figure 5 , Figure 6 as well as Figure 7In the diagram, the first carrier film 2, the second carrier film 3, and the third carrier film 5 are all marked in cyan; the aforementioned punched structure 19 is marked in magenta; the first mold positioning hole 121 and the second mold positioning hole 16 are marked in red; and the flexible circuit board 41, the flexible circuit board panel 1, and the gold fingers 42 are marked in black. It should be particularly noted that in... Figure 7 In the middle, the red markings are the first punching slot 21 and the second punching slot 31.

[0042] like Figure 5 As shown, the first mold positioning hole 121 is located in the process edge area of ​​the FPC panel and within the distance between the first area 11 and the second area 13. This first mold positioning hole 121 is mainly used for positioning the second punching process. In practical applications, the specific number and location of the first mold positioning holes 121 can be set according to the actual situation and are not limited here. For example, as... Figure 5 As shown, the FPC panel includes multiple flexible circuit boards 41 arranged in a continuous array along a second direction. There is a gap between adjacent flexible circuit boards 41. A set of first mold positioning holes 121 (e.g., one hole) is provided on each of the left and right sides of the FPC panel. Starting from one side of the FPC panel in the second direction, a set of first mold positioning holes 121 (e.g., two diagonally arranged mold positioning holes) is provided in the spacing between every few (e.g., three) flexible circuit boards 41. It should be clearly stated that the maximum distribution width of the multiple first mold positioning holes 121 along the first direction is less than or equal to the width of the spacing in the first direction. The first direction is perpendicular to the second direction.

[0043] In optional embodiments, such as Figure 5 As shown, the flexible circuit board panel 1 also has a third region 14 and a fourth region 15. Both the third region 14 and the fourth region 15 are provided with gold finger 42 pads (with gold fingers 42) and a second mold positioning hole 16. The third region 14 is connected to the first region 11 and is located on the side of the first region 11 away from the second region 13. The fourth region 15 is connected to the second region 13 and is located on the side of the second region 13 away from the first region 11.

[0044] In practical applications, the second mold positioning holes 16 are also used for positioning the second punching process. Their specific number and location can be set according to actual conditions. For example, such as... Figure 5As shown, a set of second mold positioning holes 16 (or one) are provided on each of the left and right sides of the FPC panel. Starting from one side of the FPC panel in the second direction, a set of first mold positioning holes 121 (or one) is provided in the spacing between every multiple (e.g., three) flexible circuit boards 41. It should be noted that the aforementioned first mold positioning holes 121 are concentrated in the middle area in the first direction, and the second mold positioning holes 16 are concentrated at the top and bottom ends in the first direction, so that the strip-shaped, holeless first and second carrier films can be effectively avoided.

[0045] like Figure 6 As shown, the third region 14 and the fourth region 15 are not covered by the corresponding carrier film. Based on this, compared with the window-cutting and hollowing-out design at the gold finger 42 pad and the die-cutting area 12 of the secondary punching, the present invention avoids all the quality hazards caused by the window-cutting and hollowing-out design such as the avoidance hole by not pressing the carrier film, effectively alleviates the risk of adhesive residue sticking to the gold finger 42 pad, and greatly simplifies the corresponding processing flow.

[0046] The above describes the corresponding structure on the FPC panel; the following section combines... Figure 4 as well as Figure 6 The first carrier membrane 2 and the second carrier membrane 3 are described in detail.

[0047] The first carrier film 2 and the second carrier film 3 are carrier films with identical structures and no windowed or perforated design. That is, the surfaces of the first carrier film 2 and the second carrier film 3 have no perforation holes or perforation grooves, and they are complete film structures. In practical applications, their specific structures can be selected according to actual conditions, and are not limited here. For example, in some embodiments, the first carrier film 2 and the second carrier film 3 are rectangular strips, and their length direction is consistent with the length direction of the FPC panel. The length of the first carrier film 2 and the second carrier film 3 is also consistent with the length of the FPC panel in the continuous state, ensuring that the first carrier film 2 and the second carrier film 3 can fully support the edge of the FPC board after punching in the length direction, so as to provide complete support for the edge of the finished FPC board, reduce the warping or wrinkling of the flexible circuit board product 4 during handling and packaging, and ensure the quality stability of the product during transportation and customer use, so as to simultaneously realize the dual functions of punching assistance and packaging support. Meanwhile, the width of the first carrier film 2 and the second carrier film 3 must be less than the width of the FPC panel, and the width direction (i.e. the first direction) must not cover the die punching area 12.

[0048] It should be noted that the carrier film is made of a micro-adhesive material, such as a silicone-based micro-adhesive film or an acrylic-based micro-adhesive film. Among them, silicone-based micro-adhesive films are preferred because their shear resistance and heat resistance are superior to those of acrylic-based materials, which helps to reduce adhesion to the mold during the punching process.

[0049] In practical applications, the first carrier film 2 and the second carrier film 3 may include a polyester film layer, an adhesive layer, and a peelable release film layer. The thickness of the polyester film layer is 50μm to 60μm, and the thickness of the adhesive layer is 10μm to 25μm. In specific use, the micro-adhesive carrier film raw material can first be cut into rectangular strips according to a preset fixed size to obtain the first carrier film 2 and the second carrier film 3. The fixed size matches the size of the FPC panel in a continuous state; this step does not require drilling or die-cutting for opening windows. Then, the release film layer of the cut first carrier film 2 and the second carrier film 3 is peeled off, and the first carrier film 2 and the second carrier film 3 with the release film removed are then adhered to the FPC panel.

[0050] Step 102: The first carrier film 2 is attached to the first region 11, and the second carrier film 3 is attached to the second region 13 to obtain the first product intermediate.

[0051] Specifically, two rectangular strips of carrier film are taken as the first carrier film 2 and the second carrier film 3, and are respectively attached to the first region 11 and the second region 13 of the FPC panel. After attachment, the first carrier film 2 and the second carrier film 3 maintain a corresponding spacing on the FPC panel, and the gap between the two carrier films is the mold positioning hole area on the FPC panel, exposing the first mold positioning hole 121 located thereon. That is, the first mold positioning hole 121 is completely exposed in the space not covered by the carrier film. In practical applications, the width of the mold positioning hole area in the first direction is 8mm to 12mm, and this width is not less than the maximum distribution width of all first mold positioning holes 121 on the FPC panel along the first direction.

[0052] As can be seen from the above description, compared with the design of FPC panelization with continuous support film (i.e., the support film area fully covers the panelization area), the present invention significantly reduces the amount of support film used and improves material utilization by partially applying support film (i.e. covering a local area).

[0053] In optional embodiments, such as Figure 5 as well as Figure 6 As shown, in step 102, the first carrier film 2 is attached to the first region 11, and the second carrier film 3 is attached to the second region 13 to obtain the first product intermediate, including: A first positioning reference is determined, and the first carrier film 2 is correspondingly attached to the first region 11 based on the first positioning reference; wherein, the first positioning reference includes a plurality of first marking lines 17 disposed on the edge of the first region 11; A second positioning reference is determined, and the second carrier film 3 is correspondingly attached to the second region 13 based on the second positioning reference; wherein, the second positioning reference includes a plurality of second marking lines 18 disposed on the edge of the second region 13.

[0054] Specifically, such as Figure 5 as well as Figure 6 As shown, in the first direction of the FPC panel, it may sequentially have a third region 14, a first region 11, a mold positioning hole region, a second region 13, and a fourth region 15. The first region 11 and the second region 13 are respectively fitted with a first carrier film 2 and a second carrier film 3. Correspondingly, a portion of the first marking line 17 is located on the connecting edge between the third region 14 and the first region 11, and a portion of the first marking line 17 is located on the connecting edge between the first region 11 and the mold positioning hole region. Similarly, a portion of the second marking line 18 is located on the connecting edge between the second region 13 and the mold positioning hole region, and a portion of the second marking line 18 is located on the connecting edge between the second region 13 and the fourth region 15. The first positioning reference and the second positioning reference are symmetrically arranged.

[0055] In practical applications, such as Figure 5 as well as Figure 6 As shown, the first marking line 17 and the second marking line 18 can be correspondingly set with the first mold positioning hole 121 and the second mold positioning hole 16. For example, corresponding first marking lines 17 and second marking lines 18 can be respectively set in the process edge areas on the left and right sides near the FPC panel. Starting from one side of the FPC panel in the second direction, every few (e.g., three) flexible circuit boards 41, corresponding first marking lines 17 / second marking lines 18 are set in their circuit board spacing. It should be noted that the above-mentioned first / second marking lines are used as alignment references for the first / second carrier films during bonding. They are all located in the process edge area of ​​the FPC panel and are formed by etching.

[0056] Based on this, by naturally exposing the first mold positioning hole 121 on the edge of the FPC panelization process in the mold positioning hole area between the first carrier film 2 and the second carrier film 3, punching positioning is achieved without any avoidance structure on the first carrier film 2 and the second carrier film 3, and no tool such as a jig or pin is needed for alignment during the bonding process.

[0057] As described above, compared to the need to use a fixture with pins for bonding and alignment, this invention can complete the bonding by using the pre-set straight marking lines on the FPC panel as a reference, without the need for a special fixture. The bonding efficiency is significantly improved, and the bonding deviation no longer affects the subsequent punching and positioning, fundamentally eliminating the dependence on fixture alignment and significantly improving the bonding efficiency.

[0058] In an optional embodiment, after step 102 above and before step 104 below, the method further includes: performing a sham compression process on the first product intermediate.

[0059] Based on this, the first carrier film 2 and the second carrier film 3 are temporarily pressed onto the FPC panel to make the first carrier film 2 and the second carrier film 3 fit tightly with the FPC panel. This can temporarily fix them into a whole before punching and forming, thereby preventing the finished product from scattering and shifting after cutting. The first carrier film 2 and the second carrier film 3 can directly serve as packaging carriers after waste discharge, eliminating the intermediate transfer process.

[0060] Step 104: Perform a punching and forming operation on the first product intermediate body based on the first mold positioning hole 121 to obtain the flexible circuit board product 4.

[0061] In an optional embodiment, step 104, performing a punching and forming operation on the first product intermediate based on the first mold positioning hole 121, may include the following steps: Step 200: The first product intermediate is punched and formed based on the first mold positioning hole 121; Step 202: After the punching and forming is completed, the corresponding waste material is removed to obtain the second product intermediate.

[0062] Specifically, the pre-pressed FPC panel is placed on a punching die and positioned using the first die positioning hole 121 located on the process edge area of ​​the FPC panel, and then punched into shape. After punching, the FPC waste is removed, and the carrier film adhered to the flexible circuit board 41 is used as the packaging carrier for packaging and shipment. Figure 7 As shown, it is the final shipped flexible circuit board product 4, which has a first punched slot 21 punched out on the first carrier film 2 and a second punched slot 31 punched out on the second carrier film 3.

[0063] In an optional embodiment, step 200, punching the first product intermediate body based on the first mold positioning hole 121, may include the following steps: The first product intermediate is placed on the punch press of the hardware steel mold. Positioning is performed based on the first mold positioning hole 121, and the first product intermediate is punched and formed by the hardware steel mold. The cutting edge of the metal steel mold is provided with an anti-stick coating, which is a diamond-like carbon coating or a chromium nitride coating.

[0064] In practical applications, the first intermediate product can be placed on the punch press of a metal steel mold and positioned using the first mold positioning hole 121 exposed on the edge of the FPC panelization process for secondary punching and forming. The cutting edge of the metal steel mold can be coated with an anti-stick coating, selected from diamond-like carbon (DLC) or chromium nitride (chromium nitride) coatings. Based on this, during punching, the gap between the metal steel mold and the substrate can be set to 5%–8% of the total thickness of the carrier film and the flexible circuit board 41, reducing the punching speed by 10%–15% compared to conventional punching speeds. Simultaneously, every 500–800 punches constitutes one cycle, the mold cutting edge and stripper plate are wiped with a non-woven cloth soaked in alcohol to remove any residual adhesive buildup on the cutting edge, achieving mold cleaning and maintenance.

[0065] As described above, in response to the problem of residual adhesive accumulation in the punching of metal steel molds, this invention ensures the stable mass production feasibility of the solution through supporting measures such as mold coating treatment, parameter optimization, and regular mold cleaning. Moreover, the cost of mold cleaning is much lower than the auxiliary material processing cost of drilling holes in the original bearing film and punching out windows. This punching process has good adaptability and is feasible for mass production.

[0066] In an optional embodiment, in step 104, after removing the corresponding waste to obtain the second product intermediate, the method further includes: performing FQC (Final Quality Control) inspection on the second product intermediate, and using the qualified second product intermediate as the flexible circuit board product 4.

[0067] The aforementioned FQC refers to the final inspection stage conducted after all manufacturing processes are completed, before the product is received into the warehouse or shipped. Based on inspection standards, the appearance, dimensions, performance, and packaging of the finished product are confirmed, and the entire batch is determined to be qualified for release. Its core function is to intercept defective products and ensure the quality of shipped goods. For example, the FQC stage may include: inspecting the cleanliness of the 42-area gold fingers of the die-cut product, the dimensional accuracy, and the flatness of the substrate film adhesion.

[0068] Figure 7 This is a schematic diagram of the structure of a flexible circuit board product disclosed in an embodiment of the present invention. The flexible circuit board product is obtained according to the preparation method described above, with reference to... Figure 7 The flexible circuit board product 4 includes a first carrier film 2, a second carrier film 3, and multiple flexible circuit boards 41.

[0069] The first carrier film 2 and the second carrier film 3 are arranged side by side along a first direction with a gap between them. A plurality of flexible circuit boards 41 are arranged in an array along a second direction on the first carrier film 2 and the second carrier film 3, and each flexible circuit board 41 is partially attached to the first carrier film 2 and partially attached to the second carrier film 3; wherein, the first direction is perpendicular to the second direction.

[0070] As can be seen from the above description, the beneficial effects of this invention are as follows: By using the first carrier film 2 and the second carrier film 3 arranged side by side with a spacing to support the array of flexible circuit boards 41, it avoids the waste of material from covering the entire film and eliminates the processing steps of opening windows and hollowing out to avoid misalignment. Furthermore, the spacing between the first carrier film 2 and the second carrier film 3 facilitates punching and positioning, effectively reducing production costs and process complexity. Simultaneously, after punching, the products remain in an orderly array and are directly shipped using the first carrier film 2 and the second carrier film 3 as packaging carriers, eliminating the need for additional transfer and handling, further reducing process steps and the risk of product damage.

[0071] To make this application easier to understand, an exemplary application is provided below. In this exemplary application, a method for manufacturing a flexible circuit board product is provided, which specifically includes the following steps: Step S1, Selection and cutting of the carrier film First, a silicone-based micro-adhesive carrier film is selected. The carrier film structure includes a polyester film layer, a silicone adhesive layer, and a peelable release film layer stacked sequentially. The thickness of the polyester film layer is 50 μm, the thickness of the adhesive layer is 10 μm, and the thickness of the release film layer is 25 μm.

[0072] After that, as Figure 4 As shown, the micro-adhesive carrier film material is cut into rectangular strips according to a preset fixed size to obtain the first carrier film 2 and the second carrier film 3. Specifically, according to the length of the FPC panel, the carrier film is cut into rectangular strips with a preset width. The width is determined based on the actual coverage requirements of the first area 11 and the second area 13 of the FPC panel, ensuring that the width of the carrier film does not cover the mold positioning hole area. This step only involves the cutting process and does not require drilling or mold punching for opening and hollowing out. The first carrier film 2 and the second carrier film 3 do not have any avoidance design.

[0073] Step S2, bonding of the carrier film First, such as Figure 5 As shown, the first identification line 17 and the second identification line 18 on the FPC panel are defined. It should be noted that the first identification line 17 and the second identification line 18, which are straight lines with a line width of 0.8mm, are pre-etched on the FPC panel. Both the first identification line 17 and the second identification line 18 are located in the process edge area of ​​the FPC panel. The first identification line 17 is located on the edge side of the first area 11, and the second identification line 18 is located on the edge side of the second area 13.

[0074] After that, as Figure 6As shown, the first carrier film 2 is attached to the first area 11 of the FPC panel using the first marking line 17 as the alignment reference, and the second carrier film 3 is attached to the second area 13 of the FPC panel using the first marking line 17 as the alignment reference. This step does not require the use of a jig with pins for alignment; it can be completed simply by attaching the films based on the marking line. Since the first carrier film 2 and the second carrier film 3 maintain a preset distance (e.g., 10mm) on the FPC panel, the mold positioning hole area is fully exposed, ensuring that the first mold positioning hole 121 is completely within the space not covered by the carrier film.

[0075] Step S3, dummy pressure processing The laminated FPC panel is fed into a dummy press for dummy pressing, so that the first carrier film 2 and the second carrier film 3 are tightly bonded to the FPC panel.

[0076] Step S4, punching and forming The FPC panel, after being pre-pressed, is then placed on the punch press of a metal steel mold. Positioning is achieved using the exposed mold positioning holes on the edge of the FPC panel, followed by secondary punching. During punching, the mold cutting edge is treated with a DLC coating, the mold clearance is set to 5% or 6% of the total material thickness, and the punching speed is reduced by 10% or 12%. Every 500 / 600 punches, the machine is stopped, and the cutting edge and stripper plate are wiped with a non-woven cloth soaked in alcohol.

[0077] Step S5: Waste Discharge, Inspection, and Packaging After the die-cutting process is completed, the waste material on the FPC panel is removed. After passing FQC inspection, if... Figure 7 As shown, the first and second carrier films, which are adhered to the FPC finished product, are shipped directly as packaging carriers.

[0078] Compared to the traditional continuous carrier film solution (which requires pre-processing of window openings and perforations), this invention has significant advantages in processing efficiency, material consumption, and product quality. Specifically, the auxiliary material processing cycle of the traditional solution is approximately 3.5 times that of this invention, and the lamination time is more than twice as long. In terms of material consumption, the traditional solution requires full-panel lamination (based on 100% traditional usage), while this invention uses a partial strip lamination method, reducing material consumption to 60%, saving approximately 40% of the material. Regarding product quality, the fuzz defect rate of the traditional solution is 0.55%, while this invention can reduce it to 0.06%–0.08%, the former being approximately 7–9 times that of the latter. Clearly, this invention can effectively simplify the carrier film auxiliary material processing and lamination process in the FPC back-end manufacturing process, significantly reducing carrier film usage, improving carrier film material utilization, reducing production costs, increasing production efficiency, and ensuring stable product quality, thus possessing good industrial application prospects and promotional value. Moreover, comparative experiments show that, under the same punching conditions, the cut of the carrier film after punching is neat and without delamination, and the defect rate of fuzz is reduced from more than 0.5% in the traditional solution to less than 0.08%. It is estimated that about 1 / 3 to 2 / 5 of the carrier film can be saved per panel.

[0079] In summary, the flexible circuit board product and its manufacturing method according to the present invention: (1) The non-avoiding whole film design eliminates stress concentration points on the carrier film, making the carrier film uniformly stressed during punching, and fundamentally eliminating the possibility of fuzz and adhesive peeling caused by traditional window-cutting avoidance design (such as the edge of the avoidance hole). (2) The alignment of the first marking line 17 and the second marking line 18 replaces the alignment of the fixture pins, eliminating the rigid constraint of the alignment accuracy requirement between the avoidance hole and the positioning hole, so that the bonding operation no longer depends on the precise position control of the avoidance hole. (3) The spacing design of the first carrier film 2 and the second carrier film 3 makes the mold positioning hole area completely exposed in the space without the carrier film coverage, and the punching mold directly contacts the first mold positioning hole 121 on the FPC panel for positioning, and the positioning accuracy is not affected by the bonding deviation of the carrier film. Specifically, it should be noted that, through extensive experimentation, this invention has found that when the parallelism deviation of the first carrier film 2 and the second carrier film 3, based on the first marking line 17 and the second marking line 18, is controlled within ±0.2mm, and the spacing of 8mm to 12mm completely covers the positioning hole area, zero interference of the die cutting edge can be ensured during punching. If the parallelism deviation exceeds ±0.5mm, the risk of the carrier film edge being sheared by the die increases sharply, resulting in burr defects. This invention, through the low-cost and precise benchmark of "first marking line 17 and second marking line 18," makes the non-avoiding strip solution feasible in engineering.

[0080] It should be understood that the terms "first," "second," etc., are used in this invention to describe various types of information, but these terms are not limited to them and are only used to distinguish information of the same type from each other. For example, without departing from the scope of this invention, "first" information can also be referred to as "second" information, and similarly, "second" information can also be referred to as "first" information.

[0081] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for manufacturing a flexible circuit board product, characterized in that, include: A flexible circuit board panel, a first carrier film, and a second carrier film are obtained; wherein, the flexible circuit board panel has a first region, a die-cutting region, a second region, and a first die positioning hole, the first region and the second region are disposed on opposite sides of the die-cutting region, and the first die positioning hole is located in the die-cutting region; The first carrier film is attached to the first region, and the second carrier film is attached to the second region to obtain the first product intermediate. The first product intermediate is punched and formed based on the positioning hole of the first mold to obtain a flexible circuit board product.

2. The preparation method according to claim 1, characterized in that, The process of attaching the first carrier film to the first region and attaching the second carrier film to the second region includes: A first positioning reference is determined, and the first carrier film is correspondingly attached to the first area based on the first positioning reference; wherein, the first positioning reference includes a plurality of first marking lines disposed at the edge of the first area; A second positioning reference is determined, and the second carrier film is correspondingly attached to the second region based on the second positioning reference; wherein, the second positioning reference includes a plurality of second marking lines disposed at the edge of the second region.

3. The preparation method according to claim 1, characterized in that, The first product intermediate is punched and formed based on the positioning hole of the first mold, including: The first product intermediate is punched and formed based on the positioning hole of the first mold. After the die-cutting process is completed, the corresponding waste material is removed to obtain the second product intermediate.

4. The preparation method according to claim 3, characterized in that, The first product intermediate is punched and formed based on the positioning hole of the first mold, including: The first product intermediate is placed on the punch press of the hardware steel mold. Positioning is performed based on the positioning hole of the first mold, and the intermediate body of the first product is punched and formed by the hardware steel mold. The cutting edge of the metal steel mold is provided with an anti-stick coating, which is a diamond-like carbon coating or a chromium nitride coating.

5. The preparation method according to claim 3, characterized in that, After removing the corresponding waste to obtain the second product intermediate, the process further includes: performing FQC inspection on the second product intermediate, and using the qualified second product intermediate as the flexible circuit board product.

6. The preparation method according to claim 1, characterized in that, Before performing the punching and forming operation on the first product intermediate body based on the first mold positioning hole, the method further includes: performing a dummy pressing treatment on the first product intermediate body.

7. The preparation method according to claim 1, characterized in that, The flexible circuit board panel also has a third region and a fourth region. Both the third region and the fourth region are provided with gold finger pads and second mold positioning holes. The third region is connected to the first region and is located on the side of the first region away from the second region. The fourth region is connected to the second region and is located on the side of the second region away from the first region.

8. The preparation method according to claim 1, characterized in that, The carrier film includes a polyester film layer and an adhesive layer, wherein the thickness of the polyester film layer is 50μm to 60μm and the thickness of the adhesive layer is 10μm to 25μm.

9. The preparation method according to claim 1, characterized in that, The number of the first mold positioning holes is multiple, and the maximum distribution width of the multiple first mold positioning holes along the first direction is less than or equal to the width of the mold punching area in the first direction.

10. A flexible circuit board product, characterized in that, The flexible circuit board product obtained by the preparation method according to any one of claims 1-9 includes a first carrier film, a second carrier film, and a plurality of flexible circuit boards. The first carrier film and the second carrier film are arranged side by side along a first direction and have a gap between them. The plurality of flexible circuit boards are arranged in an array along a second direction on the first carrier film and the second carrier film, and each flexible circuit board is partially attached to the first carrier film and partially attached to the second carrier film; wherein, the first direction is perpendicular to the second direction.

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