Manufacturing processes for circuits and fuses for flexible printed circuit boards

Abstract

This disclosure provides a fabrication process for circuits and fuses for a flexible printed circuit board. The fabrication process for circuits and fuses includes: pressing and bonding a release liner to the underside of a polyethylene terephthalate silicone film using an upper rubber roller and a lower steel roller; removing the release liner, based on a circuit and fuse retention position on the metal foil, at an alignment position for the circuit and fuse on the bottom of the PET silicone film using a lower circular knife die and holding the release liner outside the alignment position for the circuit and fuse; aligning the PET silicone film, based on the circuit and fuse retention position on the metal foil, thereby removing the release liner.Pressing and bonding, using an upper rubber roller and a lower steel roller, the metal foil to the PET silicone film with a release liner side; cutting the circuit and fuse with the lower circular blade shape; bonding a PET silicone film to the underside of the metal foil after cutting the circuit and fuse; removing the PET silicone film from the bottom of the metal foil and any metal foil waste; and holding the cut circuit and fuse on the PET silicone film with the release liner side.

Description

TECHNICAL AREA

[0001] The present disclosure relates to the field of processing flexible printed circuit boards and in particular to a manufacturing process for circuits and fuses for a flexible printed circuit board. BACKGROUND

[0002] With the development of modern society, electric vehicle charging stations are ubiquitous in China. The explosive growth in sales of new energy vehicles has fueled domestic demand and boosted foreign exchange earnings. Due to battery range limitations, flexible printed circuit boards (FPCBs) are being used to replace most wiring harnesses, thereby increasing battery capacity and improving range. Currently, the fabrication of circuits and fuses at FPCBs mainly involves the following steps: A metal foil 2 is directly bonded to the underside of a polyethylene terephthalate (PET) silicone film 1, and a circuit and fuse 4 are formed by die cutting. A PET silicone film 3 is bonded to the underside of the metal foil. The PET silicone film at the bottom of the metal foil and any metal foil waste are removed.The circuit formed by cutting and the fuse are held on the PET silicone film over the metal foil, as shown in . Fig. Figure 1 illustrates this. Because the PET silicone film is adhered directly to the underside of the metal foil, the retained circuit and fuse are in the same plane as the metal foil waste. When the PET silicone film is removed from the bottom of the metal foil and the metal foil waste is removed, the delicate and flexible circuit and fuse can easily be pulled upwards or downwards by the peeling force. This makes the delicate and flexible circuit and fuse on the metal foil susceptible to problems such as misalignment and deformation, thus affecting the yield of the FPCB product. Even with slow peeling of the waste, it is difficult to improve the yield, resulting in a reduction in production efficiency.

[0003] Especially when the fuse is manufactured on metal foil, to ensure it can interrupt the circuit in the event of a high current, the fuse's thickness and lead width must be very small. However, fuses with very small thickness and lead widths are more prone to misalignment and deformation due to upward or downward pulling by the removal force. SUMMARY

[0004] One objective of this disclosure is to provide a fabrication process for circuits and fuses for a flexible printed circuit board that solves the problems of misalignment and deformation of a circuit and fuse on a metal foil and improves the yield of the FPCB product.

[0005] This disclosure provides a fabrication process for circuits and fuses for the FPCB, which includes the following steps: S1: Pressing and bonding, by means of an upper rubber roller and a lower steel roller, a release film with an original film having a thickness of 0.02-0.08 mm, a release adhesive having a thickness of 0.001-0.005 mm and a pull-off force of 1-10 G onto the underside of a polyethylene terephthalate silicone film which has an original film having a thickness of 0.06-0.08 mm, an adhesive having a thickness of 0.01-0.03 mm and a pull-off force of 600-1000 G; S2: Removal, based on a position for holding a circuit and fuse on a metal foil with a thickness of 0.03 to 0.12 mm, of the release liner at an alignment position for circuit and fuse at the bottom of the PET silicone film by means of a bottom circular knife shape, wherein a width of the removed release liner is 0.1 to 0.2 mm greater than the width of the circuit and fuse; and holding the release liner that is outside the position for the alignment of circuit and fuse; S3: Align, based on the position to hold the circuit and fuse on the metal foil, the position of the PET silicone film, removing the release liner; press and bond the metal foil to one release liner side of the PET silicone film by the upper rubber roller and the lower steel roller; and cut by a lower circular blade die to form a circuit and a curved fuse; and S4: Adhere a PET silicone film to the underside of the metal foil after cutting to form the circuit and fuse; remove the PET silicone film from the bottom of the metal foil and any metal foil waste; and hold the circuit and fuse formed by cutting on the release liner side of the PET silicone film.

[0006] The fuse includes a spherical fuse and / or a bent fuse; the spherical fuse is formed by spherical metal foils connected in series; a connecting lead of each of the spherical metal foils has a lead width of 0.12-0.18 mm; and the bent fuse has a lead width of 0.12-0.18 mm.

[0007] However, the protection is not limited to the two types mentioned above, and other fuses with a conductor width of 0.12 to 0.18 mm are within the scope of protection of this disclosure.

[0008] In the above-mentioned process, the original film thickness, the adhesive thickness and the peel strength of the PET silicone film, the original film thickness and the release adhesive thickness of the release film, as well as the width of the removed release film, all have a significant impact on the yield.

[0009] The original PET silicone film primarily plays a supporting role, and if its thickness is too small, it causes insufficient support.

[0010] The adhesive on the PET silicone film primarily serves as a bonding agent during the cutting process between the release liner and the metal circuit, and also acts as a buffer. If the adhesive is too thin, the original film can be easily damaged during the cutting process. If the adhesive is too thick, it can cause slight vertical movement of the metal film during cutting, which can lead to a reduction in yield.

[0011] Adequate peel force of the PET silicone film prevents the release film and the metal foil from slipping during the cutting process and prevents the conductive circuit and the fuse from being misaligned, deformed or even damaged during the peeling process.

[0012] The thickness of the release liner refers primarily to the thickness of the metal foil. The sum of the original release liner thickness and the thickness of the release adhesive is less than the thickness of the metal foil. This allows the metal foil to be recessed into the liner and, after rolling, bonded to the high-viscosity PET silicone film. Following cutting of the circuit, this results in an offset structure, preventing damage during the waste removal process.

[0013] In step S2, the width of the removed separating film is 0.1–0.2 mm greater than the width of the circuit and fuse. This ensures that the pre-defined portion of the circuit and fuse on the metal foil is bonded to the PET silicone film before cutting, thus forming the circuit and fuse and preventing misalignment, deformation, or even damage to the metal foil during the cutting process.

[0014] In a preferred solution of the present disclosure, the PET silicone film in step S1 has an original film with a thickness of 0.065 to 0.075 mm, an adhesive with a thickness of 0.02 to 0.025 mm and a pull-off force of 700 to 800 G.

[0015] In a preferred solution of the present disclosure, the thickness (a sum of the original foil thickness and the release adhesive thickness) of the release film is 0.6 to 0.8 times the thickness of the metal foil.

[0016] In a preferred solution of the present disclosure, the separating film is a one-sided adhesive separating film, wherein one one-sided adhesive side faces downwards and touches the metal foil.

[0017] In a preferred solution of the present disclosure, the fabrication process of the circuit and fuse for the FPCB further includes: flattening / shaping the circuit and fuse, which are held on the side of the PET silicone film with the release film, by upper and lower steel rollers, thereby flattening / shaping the circuit and fuse on the metal foil.

[0018] In a preferred solution of the present disclosure, the fabrication process of circuits and fuses for the FPCB further includes: heating and bonding a thermoset adhesive film onto the PET silicone film by means of the upper rubber roller, the lower steel roller and the upper and lower heating rollers, wherein the PET silicone film is located at the bottom of the thermoset adhesive film and the heating rollers are heated to 100-140 °C; Heating and bonding of the thermosetting adhesive film to the metal foil with the circuit and the fuse by the upper rubber roller, the lower steel roller and the upper and lower heating rollers, wherein the thermosetting adhesive film is located at the bottom on the release film side of the PET silicone film; Remove the PET silicone film along with the release liner side; Performing the opening of the solder mask on the metal foil with the circuit and fuse after removing the PET silicone film and the release film; and heating and pressing the thermosetting adhesive film through the upper and lower heating rollers; and Removing the PET silicone film from the bottom of the thermosetting adhesive film along with any soldering waste.

[0019] In a preferred solution of the present disclosure, the thermoset adhesive film is a thermoset polyimide (PI) adhesive film or a thermoset PET adhesive film with a thickness of 0.05 to 0.15 mm.

[0020] The metal foil suitable for the process of the present disclosure comprises one or more of the following foils: copper foil (pure copper foil), aluminum foil, constantan foil, aludirom foil, stainless steel foil, brass foil, gold foil, nickel foil, iron foil, cupronickel foil, silver foil, manganin foil, chromium nickel foil, Ni / Al foil.

[0021] In a preferred solution of the present disclosure, the adhesive of the PET silicone film includes a highly viscous agent.

[0022] In the FPCB's fabrication process for circuits and fuses, disclosed in this publication, the PET silicone film with specific parameters / release film with specific parameters is primarily used. The pre-defined circuit and fuse leads are formed by cutting a corresponding portion of the release film to create a concave recess for the circuit and fuse leads. The metal foil is pressed onto the release film side, and the portion of the metal foil containing the leads is recessed into the recess for the circuit and fuse leads and bonded to the high-viscosity PET silicone film. The metallic copper foil bonded to the high-viscosity PET silicone film is then cut to create a regular conductive lead and fuse.The conductive wire and the fuse all fall into the designated positions for the circuit conductor and the fuse lead, and their thickness is greater than that of the separating film, thus creating sufficient space between the layers. Even if the separating film and metal foil waste are quickly removed, misalignment and deformation of the conductive wire and fuse are not easily caused. Therefore, the process described in this disclosure offers the advantages of high yield and high efficiency and is particularly suitable for the production of fuses with complex structures and small thicknesses / widths. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a schematic diagram of an existing manufacturing process for circuits and fuses for a flexible printed circuit board (FPCB) according to the state of the art; Fig.Figure 2 is a flowchart of a manufacturing process for circuits and fuses for the FPCB according to the present disclosure; Fig. Figure 3 is a schematic diagram showing that a release film is glued to the underside of a polyethylene terephthalate (PET) silicone film; Fig. Figure 4 is a schematic diagram of cutting the separating film; Fig. Figure 5 is a schematic diagram after the removal of the separating film; Fig. Figure 6 is a schematic diagram of pressing and bonding a metal foil to a release liner side of the PET silicone film; Fig. Figure 7 is a schematic diagram of the cutting process to form a circuit and a fuse; Fig. 8 is a schematic diagram of the fuse; Fig.Figure 9 is a schematic diagram of the bonding of a PET silicone film to the underside of the metal foil, the circuit and the fuse being formed by cutting; Fig. Figure 10 is a schematic diagram of the holding of the circuit formed by cutting on the release liner side of the PET silicone film and the securing mechanism; Fig. Figure 11 is a schematic diagram of the flattening of the circuit and the fuse on the metal foil; Fig. Figure 12 is a schematic diagram of the heating and bonding of a thermosetting adhesive film 17 to the metal foil with the circuit and the fuse; and Fig. Figure 13 is a schematic diagram of the removal of the PET silicone film at the bottom of the thermoset adhesive film and solder waste. DETAILED DESCRIPTION OF THE EXECUTION FORMS

[0023] The technical solutions in the embodiments of this disclosure are clearly and completely described below with reference to the drawings. Obviously, the described embodiments are only some, and not all, of the embodiments of this disclosure. All other embodiments that could be obtained by those skilled in the art based on the embodiments of this disclosure without creative effort should fall within the scope of protection of this disclosure.

[0024] As in Fig. As shown in Figure 2, the fabrication process for circuits and fuses for a flexible printed circuit board (FPCB) includes the following steps. S1. The upper rubber roller 5 and the lower steel roller 6 press and bond the release film 7, which has an original film with a thickness of 0.02 to 0.08 mm, a release adhesive with a thickness of 0.001 to 0.005 mm and a peel force of 1 to 10 G, to the underside of the PET silicone film 8, which has an original film with a thickness of 0.06 to 0.08 mm, an adhesive with a thickness of 0.01 to 0.03 mm and a peel force of 600 to 1,000 G, as shown in Fig. 3 shown.

[0025] The PET silicone film is a PET silicone film with a high-viscosity adhesive. This high-viscosity PET silicone film can be bonded to the release liner and then to a metal foil, ensuring a more stable bond. The PET silicone film features a core film thickness of 0.065-0.075 mm, an adhesive layer thickness of 0.02-0.025 mm, and a peel strength of 700-800 G. The core film bonds well to the release liner, providing stable support for cutting the release liner to width, which is important for improving the overall process yield. Furthermore, the release liner is a single-sided adhesive film, with one adhesive side facing down and in contact with the metal foil, and the other non-adhesive side bonded to the PET silicone film. This allows for easy and complete removal of the release liner after subsequent hot pressing.

[0026] S2. Based on a position for holding a circuit and fuse on a metal foil with a thickness of 0.03 to 0.12 mm, the separator film is cut at an alignment position for the circuit and fuse at the bottom of the PET silicone film by the lower circular knife shape 9. The width of the removed separator film 10 is 0.1–0.2 mm greater than the width of the circuit and fuse, and the separator film located outside the alignment position for the circuit and fuse is held as shown in Fig. 4 and Fig. 5 shown.

[0027] When the release liner is cut, the width of the cutting area is 0.1–0.2 mm larger than the width of the circuit and fuse. This makes it easier to embed the circuit and fuse in the concave designated space on the metal foil, resulting in convenient operation. Additionally, an experiment demonstrates that if the release liner is 0.6–0.8 times thicker than the metal foil, the circuit and fuse are less likely to come into contact with during removal of the release adhesive and metal foil debris, thus improving the yield.

[0028] S3. Position 12 for holding the circuit and the fuse on the metal foil 11 is aligned with the position of the PET silicone film, with the release liner removed, and the upper rubber roller and the lower steel roller press and bond the metal foil to one release liner side of the PET silicone film, as shown in Fig. 6 shown. The circuit and fuse are formed by cutting with the lower circular knife shape 9, as shown in Fig. Figure 7 shows the fuse. The fuse includes a spherical fuse 14 and a curved fuse 15, as shown in Fig. Figure 8 shows the spherical fuse. It is formed by spherical metal foils connected in series. Each connecting lead of the spherical metal foils has a conductor width of 0.12–0.18 mm. The bent fuse also has a conductor width of 0.12–0.18 mm.

[0029] The fuse design includes, but is not limited to, spherical and bent fuses. The lead width of each spherical copper foil is 0.12–0.18 mm. The lead width of the bent fuse is also 0.12–0.18 mm. This design allows the fuse to blow quickly in the event of a short circuit or excessive current, thus protecting other circuits.

[0030] The metal foil consists of a double-sided polished material with a surface dyn value of ≥ 36, which improves the surface adhesion of the metal foil and facilitates the bonding of the release film to the metal foil.

[0031] S4. The PET silicone film 16 is glued to the bottom of the metal foil after the circuit and fuse have been formed by cutting, as shown in Fig.9 shown. The PET silicone film at the bottom of the metal foil and the metal foil waste are removed, and the removed circuit and fuse 13 are held on the release liner side of the PET silicone film, as shown in Fig. 10 shown.

[0032] The metal foil suitable for the process disclosed herein includes copper foil, aluminum foil, constantan foil, aludirom foil, stainless steel foil, brass foil, gold foil, nickel foil, iron foil, cupronickel foil, silver foil, manganese foil, chromium-nickel foil, Ni / Al foil, etc. The metal foil may also be a combination of several foils, depending on the material required for the circuit and the fuse.

[0033] For the circuit and fuse held on the release liner side of the PET silicone film, the circuit and fuse on the metal foil are flattened / formed by upper and lower steel rollers to flatten the circuit and fuse on the metal foil, as shown in Fig. 11 is shown, with convenient subsequent processing provided.

[0034] A thermosetting adhesive film 17 is heated and applied to the PET silicone film 16 via the upper rubber roller, the lower steel roller, and the upper and lower heating rollers. The PET silicone film 16 is positioned on the underside of the thermosetting adhesive film 17. On the flattened / shaped metal foil, the thermosetting adhesive film 17 is heated and bonded to the metal foil containing the circuit and fuse by the upper rubber roller, the lower steel roller, and the upper and lower heating rollers 18. The thermosetting adhesive film is positioned on the underside of the release liner of the PET silicone film 8, as shown in Fig.Figure 12 shows the PET silicone film with the release liner side removed along with the release liner. After the PET silicone film and release liner have been removed, the solder mask opening is made on the metal foil containing the circuit and fuse. The thermoset adhesive film is heated and pressed through the upper and lower heating rollers. The PET silicone film at the bottom of the thermoset adhesive film and any solder residue are removed, as shown in Figure 12. Fig.Figure 13 illustrates this. The circuit and fuse are thus covered and protected, facilitating the subsequent fabrication of the FPCB using the metal foil. The PET silicone film underneath the thermoset adhesive film is also a PET silicone film with a high viscosity. The PET silicone film has a thickness of 0.06 mm and a pull-off force of 10-80 G. The thermoset adhesive film is a thermoset polyimide (PI) adhesive film or a thermoset PET adhesive film with a thickness of 0.05-0.15 mm. An acrylic film with a thickness of 0.05 mm and a pull-off force of 1-20 G can be selected to prevent deformation when peeling off the product through-hole. Furthermore, the parameters of the fabrication process for the circuits and fuses of the FPCB can be adapted for product manufacturing, and various tests are performed as follows.

[0035] Regarding yield, fewer than 1,000 circuits are fabricated based on the process of one embodiment and a comparative example. Whether the circuit and fuse are displaced and / or deformed is observed and recorded; deviations between the circuit and fuse and the design are monitored, and the yield is calculated.

[0036] Key parameters and test results in the procedures of embodiment (A) and comparison example (B) are shown in the table below. A1 A2 A3 A4 A5 A6 S1 Copper foil thickness, mm 0,05 0,10 0,08 0,08 0,08 0,08 Original thickness of the separating film, mm 0,03 0,7 0,02 0,045 0,06 0,07 Thickness of the release agent, µm 2 3 5 4 2 3 Pullback force, G 5 8 3 3 3 3 Original film thickness of PET, mm 0,06 0,08 0,08 0,08 0,08 0,08 Adhesive thickness of the PET film, mm 0,02 0,03 0,03 0,03 0,03 0,03 Pullback force, G 800 1000 1000 1000 1000 1000 S2 Circular knife shape, teeth 100 200 150 150 150 150 Difference between the width of the separating foil and the width of the corresponding circuit and fuse, mm 0,1 0,2 0,2 0,2 0,2 0,2 Yield, % 90,3 91,7 88,5 90,8 91,4 89,1

[0037] Continued from the table A7 A8 A9 A10 S1 Copper foil thickness, mm 0,08 0,08 0,08 0,08 Original thickness of the separating film, mm 0,06 0,06 0,06 0,06 Thickness of the release adhesive, µm 2 2 2 2 Pullback force, G 3 3 3 3 Original film thickness of the PET, mm 0,065 0,075 0,06 0,08 Adhesive thickness of the PET film, mm 0,025 0,02 0,01 0,03 Pullback force, G 700 800 600 1000 S2 circular knife shape, teeth 150 150 150 150 Difference between the width of the separating foil and the width of the corresponding circuit and fuse, mm 0,2 0,2 0,2 0,1 Yield, % 92,4 91,9 87,4 91,0

[0038] Continued from the table B1 B2 B3 B4 B5 S1 Copper foil thickness, mm 0,08 0,08 0,08 0,08 0,08 Original thickness of the separating film, mm 0,08 0,10 0,06 0,06 0,06 Thickness of the release agent, µm 2 2 10 2 2 Pullback force, G 3 3 30 3 3 Original film thickness of PET, mm 0,065 0,065 0,065 0,065 0,065 Adhesive thickness of the PET film, mm 0,025 0,025 0,025 0,025 0,025 Pullback force, G 700 700 700 400 1500 S2 circular knife shape, teeth 150 150 150 150 150 Difference between the width of the separating foil and the width of the corresponding circuit and fuse, mm 0,2 0,2 0,2 0,2 0,2 Yield, % 77,4 74,3 81,1 77,6 82,4

[0039] Continued from the table B6 B7 B8 B9 B10 S1 Copper foil thickness, mm 0,08 0,08 0,08 0,08 0,08 Original thickness of the separating film, mm 0,06 0,06 0,06 0,06 0,06 Thickness of the release agent, µm 2 2 2 2 2 Pullback force, G 3 3 3 3 3 Original film thickness of PET, mm 0,065 0,065 0,045 0,065 0,065 Adhesive thickness of the PET film, mm 0,025 0,025 0,025 0,040 0,005 Pullback force, G 700 700 700 700 700 S2 circular knife shape, teeth 150 150 150 150 150 Difference between 0,05 0,25 0,2 0,2 0,2 the width of the separating foil and the width of the corresponding circuit and fuse, mm Yield, % 75,4 77,3 79,7 81,4 81,2

[0040] The above test results show that the products manufactured by the FPCB circuit and fuse fabrication process provided in this disclosure have the advantages of high yield and efficiency, and that the circuit and fuse fabrication process is particularly suitable for the manufacture of fuses with complex structures and low thickness / width.

[0041] Specifically, according to A5 / A7-A9, a higher yield is achieved by selecting the PET silicone film with the preferred parameters. According to A3-A6, a thickness of the separating film that is 0.6 to 0.8 times the thickness of the metal foil corresponds to a higher yield. According to B1 / B2, if the thickness of the separating film is greater than or equal to the thickness of the metal foil According to B3, if the thickness of the release adhesive is too great and the pull-off force is too high, there is a risk that the circuit and the fuse will be damaged during removal, resulting in a lower yield. According to B4, if the pull-off force of the PET silicone film is too low, this causes the metal foil to slip during the cutting process, resulting in a misalignment of the circuit cut. According to B5, it also causes a reduction in yield if the pull-off force of the PET silicone film is too high. According to B6 / B7, if the difference between the width of the removed separating film and the width of the corresponding circuit and fuse is not within the scope of this disclosure, it will result in a non-compliant cutting of the circuit and fuse. According to B8, support is insufficient if the thickness of the original PET silicone film is too small, resulting in a low product yield. According to B9, if the adhesive thickness of the PET silicone film is too great, this causes a slight displacement of the removed circuit during the cutting process, leading to a reduction in yield. According to B10, the original PET silicone film can be easily damaged during the cutting process if the adhesive thickness of the PET silicone film is too low, leading to a reduction in strength and a reduction in yield.

[0042] The detailed solutions of this disclosure are described by the embodiments above, but this disclosure is not limited to the detailed solutions above; that is, it does not mean that this disclosure must refer to the detailed solutions above in order to be implemented. Those skilled in the art should understand that any improvement of this disclosure, the equivalent substitution of any raw material of the product of this disclosure, the addition of excipients, the selection of specific methods, and the like fall within the scope of protection and disclosure of this disclosure.

Claims

Manufacturing process for circuits and fuses for a flexible printed circuit board, comprising the following steps: S1: Pressing and bonding, by means of an upper rubber roller and a lower steel roller, a release film having an original film with a thickness of 0.02-0.08 mm, a release adhesive with a thickness of 0.001-0.005 mm and a pull-off force of 1-10 G onto the underside of a polyethylene terephthalate silicone film having an original film with a thickness of 0.06-0.08 mm, an adhesive with a thickness of 0.01-0.03 mm and a pull-off force of 600-1000 G;S2: Removal, based on a position for holding a circuit and fuse on a metal foil with a thickness of 0.03 to 0.12 mm, of the release liner at an alignment position for the circuit and fuse at the bottom of the PET silicone film by a lower circular knife die, wherein the width of the removed release liner is 0.1 to 0.2 mm greater than the width of the circuit and fuse; and holding the release liner outside the position for the alignment of the circuit and fuse; S3: Aligning, based on the position for holding the circuit and fuse on the metal foil, the position of the PET silicone film, removing the release liner; pressing and bonding the metal foil to a release liner side of the PET silicone film by the upper rubber roller and the lower steel roller; and cutting by the lower circular knife die to form the circuit and fuse;andS4: Adhering a PET silicone film to the underside of the metal foil after cutting to form the circuit and fuse; removing the PET silicone film from the bottom of the metal foil and any metal foil waste; and holding the circuit and fuse formed by cutting on the release liner side of the PET silicone film. A manufacturing method for circuits and fuses for the FPCB according to claim 1, wherein the fuse comprises a spherical fuse and / or a bent fuse; the spherical fuse is formed by spherical metal foils connected in series; a connecting lead of each of the spherical metal foils has a lead width of 0.12 to 0.18 mm; and the bent fuse has a lead width of 0.12 to 0.18 mm. Manufacturing method for circuits and fuses for the FPCB according to claim 1, wherein in step S1 the PET silicone film comprises an original film with a thickness of 0.065 to 0.075 mm, an adhesive with a thickness of 0.02 to 0.025 mm and a pull-off force of 700 to 800 G. Manufacturing method for circuits and fuses for the FPCB according to claim 1, wherein the separating film has a thickness that is 0.6 to 0.8 times the thickness of the metal foil. Manufacturing method for circuits and fuses for the FPCB according to claim 1, wherein the separating film is a single-sided adhesive separating film, wherein a single-sided adhesive side faces downwards and touches the metal foil. A manufacturing method for circuits and fuses for the FPCB according to claim 1, further comprising: flattening / shaping the circuit and fuse, which are held on the side of the PET silicone film with the separating film, by upper and lower steel rollers, wherein the circuit and fuse are flattened / shaped on the metal foil. A manufacturing method for circuits and fuses for the FPCB according to claim 6, further comprising: heating and bonding a thermoset adhesive film to the PET silicone film by means of the upper rubber roller, the lower steel roller, and the upper and lower heating rollers, wherein the PET silicone film is located at the bottom of the thermoset adhesive film; heating and bonding the thermoset adhesive film to the metal foil with the circuit and the fuse by means of the upper rubber roller, the lower steel roller, and the upper and lower heating rollers, wherein the thermoset adhesive film is located at the bottom of the release liner side of the PET silicone film; removing the PET silicone film with the release liner side together with the release liner; performing the opening of the solder mask on the metal foil with the circuit and the fuse after removal of the PET silicone film and the release liner; and heating and pressing the thermoset adhesive film by means of the upper and lower heating rollers;and removal of the PET silicone film at the bottom of the thermoset adhesive film along with any soldering waste. Manufacturing method for circuits and fuses for the FPCB according to claim 7, wherein the thermoset adhesive film is a thermoset polyimide (PI) adhesive film or a thermoset PET adhesive film with a thickness of 0.05 to 0.15 mm. Fabrication method for circuits and fuses for the FPCB according to claim 1, wherein the metal foil comprises at least one from the group consisting of copper foil, aluminum foil, constantan foil, aludirom foil, stainless steel foil, brass foil, gold foil, nickel foil, iron foil, cupronickel foil, silver foil, manganin foil, chromium nickel foil and Ni / Al foil. Manufacturing method for circuits and fuses for the FPCB according to claim 1, wherein the adhesive of the PET silicone film comprises a high-viscosity agent.

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