An EMI shielding film mounting structure and its preparation method

Abstract

This invention discloses an EMI shielding film mounting structure and its preparation method. The EMI shielding film mounting structure includes: a high-adhesion transfer film with an adhesive surface; a masking film disposed on the adhesive surface, the masking film including multiple cutout areas that partially expose the adhesive surface to form multiple exposed adhesive areas; and an EMI unit array layer including multiple EMI shielding film units, each EMI shielding film unit including a shielding film and a surface release film covering the shielding film, each EMI shielding film unit being adhered to a corresponding exposed adhesive area via the surface release film. In this invention, by precisely positioning and temporarily fixing multiple EMI shielding film units on the high-adhesion transfer film at once, it is convenient to subsequently remove the surface release films of all EMI shielding film units adhered to by the high-adhesion transfer film all at once, effectively improving the mounting and film removal efficiency.

Description

Technical Field

[0001] This invention relates to the field of shielding film technology, and in particular to an EMI shielding film mounting structure and its preparation method. Background Technology

[0002] In the design of high-density flexible circuit boards used in high-end consumer electronics and wearable devices, the electromagnetic interference shielding area is often divided into multiple isolated, narrow, U-shaped patterns due to the constraints of compact internal wiring and mechanical space. This highly dispersed and finely structured shielding film layout poses significant challenges to traditional manufacturing processes, primarily in the following aspects: First, automated placement of individual components is difficult to achieve. Due to the fragile structure and light weight of a single U-shaped shielding film, it is prone to deformation, drift, or unstable adsorption during automatic pickup, resulting in poor positioning accuracy and extremely low placement yield, which cannot meet the efficiency and consistency requirements of mass production.

[0003] Secondly, manual application is inefficient. While it is possible to manually apply multiple dispersed shielding films one by one, the process is slow, inconsistent in placement, and expensive, making it unsuitable for mass production.

[0004] Furthermore, the subsequent film removal process is cumbersome. Each individual shielding film needs to have its release film removed separately after being attached and pressed. When there are dozens or even hundreds of such dispersed units in the circuit, removing the film one by one is not only time-consuming and labor-intensive, but also prone to omissions, seriously affecting overall production efficiency and product reliability. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an EMI shielding film mounting structure and its preparation method, so as to solve the problem of low efficiency in EMI shielding film mounting and peeling.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: an EMI shielding film mounting structure, comprising: a high-adhesion transfer film having an adhesive surface; a masking film disposed on the adhesive surface, the masking film including multiple cutout areas, the cutout areas partially exposing the adhesive surface to form multiple exposed adhesive areas; and an EMI unit array layer including multiple EMI shielding film units, each EMI shielding film unit including a shielding film and a surface release film covering the shielding film, each EMI shielding film unit being adhered to the corresponding exposed adhesive area through the surface release film.

[0007] Furthermore, the EMI shielding film mounting structure of the present invention also includes a carrier release film, which is disposed on the side of the EMI unit array layer away from the high-adhesion transfer film.

[0008] Furthermore, in the EMI shielding film mounting structure of the present invention, the high-adhesion transfer film is provided with a plurality of positioning holes, all of which are located on the edge side of the high-adhesion transfer film.

[0009] Furthermore, in the EMI shielding film mounting structure of the present invention, the thickness of the high-adhesion transfer film is 0.05mm to 0.075mm, and the adhesive force of the adhesive surface on the high-adhesion transfer film is greater than the peeling force of the surface release film.

[0010] Furthermore, in the EMI shielding film mounting structure of the present invention, the EMI shielding film unit includes a main body and a protrusion connected to each other. The main body is U-shaped, and the protrusion is located on the side of the main body.

[0011] Accordingly, another objective of the present invention is to provide a method for preparing an EMI shielding film mounting structure, comprising: attaching a masking film to the adhesive surface of a high-adhesion transfer film; performing a first depth-controlled die-cutting on the masking film to form a cutout area, and then peeling off the waste material to obtain an initial transfer film having an exposed adhesive area and an adhesive-free masking area; attaching an EMI roll onto the initial transfer film, and performing a second depth-controlled die-cutting on the EMI roll to form an EMI unit array layer; attaching a carrier release film below the EMI unit array layer; and performing a third depth-controlled die-cutting on the high-adhesion transfer film, and peeling off the edge waste material of the high-adhesion transfer film to obtain the EMI shielding film mounting structure.

[0012] Furthermore, in the preparation method described in this invention, the EMI roll material is subjected to a second depth-controlled die-cutting to form an EMI unit array layer, which includes: performing a second depth-controlled die-cutting on the EMI roll material and peeling off the EMI waste material on the un-adhesive masking area to form a plurality of arrayed EMI shielding film units, so that the EMI shielding film units are located on the exposed adhesive area.

[0013] Furthermore, in the preparation method described in this invention, the preparation method may further include: punching out positioning holes while performing the first depth control die-cutting of the shielding film; and using the positioning holes for precise positioning during the second and third depth control die-cutting.

[0014] Furthermore, in the preparation method described in this invention, the step of laminating the EMI roll material onto the initial transfer film includes: obtaining an EMI roll material with the bottom release film removed and the adhesive surface exposed; and laminating the EMI roll material onto the initial transfer film in roll form using a die-cutting positioning system; wherein the lamination position of the EMI roll material satisfies the following condition: the distance between the EMI roll material and the edge of the positioning hole is greater than or equal to 2 mm.

[0015] Furthermore, in the preparation method described in this invention, the depth of the second controlled-depth die-cut is controlled to completely break the EMI unit array layer without breaking the high-adhesion transfer film; the depth of the third controlled-depth die-cut is controlled to completely break the high-adhesion transfer film without breaking the carrier release film.

[0016] The beneficial effects of this invention are as follows: By using a composite structure of a high-adhesion transfer film and a masking film, multiple independent EMI shielding film units that were originally dispersed, narrow, and easily deformable are integrated into a continuous material. In other words, the originally dispersed, small, irregularly shaped EMI shielding film units are physically integrated into an array of materials that can be operated as a whole. This solves the problems of easy deformation, drift, and positioning difficulties caused by the fragile structure and small size of individual EMI shielding films during automatic pickup. Simultaneously, by utilizing the adhesive relationship between the surface release film of the EMI shielding film unit and the exposed adhesive area of ​​the high-adhesion transfer film, precise positioning and temporary fixation of the EMI shielding film unit on the high-adhesion transfer film are achieved. Based on this, after the above-mentioned EMI shielding film mounting structure is pressed onto the flexible circuit board, the surface release films of all the EMI shielding film units adhered to can be removed at once by peeling off the high-adhesion transfer film, effectively improving the mounting and film removal efficiency. This solves the problem in the prior art where the surface release film of each independent EMI film needs to be removed individually after mounting and pressing, resulting in time-consuming operations and easy omissions. Attached Figure Description

[0017] Figure 1 This is a cross-sectional layered structure diagram of the EMI shielding film mounting structure described in this invention.

[0018] Figure 2 This is a bottom view of the EMI shielding film mounting structure described in this invention after the support release film has been removed.

[0019] Figure 3 This is a flowchart illustrating the steps of the preparation method of the EMI shielding film mounting structure described in this invention.

[0020] Figure 4 This is a cross-sectional view of the EMI shielding film mounting structure of the present invention, showing the first die-cutting position of the shielding film in the high-adhesion transfer film and shielding film assembly during the preparation process.

[0021] Figure 5 This is a schematic cross-sectional view of the EMI shielding film mounting structure of the present invention after the first die-cutting and removal of waste material from the shielding film in the high-adhesion transfer film and shielding film assembly during the preparation process.

[0022] Figure 6 This is a bottom view of the EMI shielding film mounting structure of the present invention after the first die-cutting and punching of positioning holes during the manufacturing process.

[0023] Figure 7 for Figure 6 The diagram shows a cross-sectional view of the high-viscosity transfer film and masking film assembly.

[0024] Figure 8 This is a bottom view of the EMI shielding film mounting structure of the present invention during the preparation of attaching EMI roll material onto a high-adhesion transfer film.

[0025] Figure 9 This is a schematic diagram illustrating the process of attaching EMI shielding film onto a high-adhesion transfer film during the fabrication of the EMI shielding film mounting structure described in this invention.

[0026] Figure 10 This is a partial cross-sectional view of the EMI shielding film mounting structure of the present invention after the EMI roll material is covered and bonded to the high-adhesion transfer film during the preparation process.

[0027] Figure 11 In order to prepare Figure 10 The diagram shows a partial cross-sectional view of the structure after the protective release film on the EMI roll has been removed.

[0028] Figure 12 In order to prepare the product Figure 11 This diagram illustrates the determination of the second die-cutting position during the second depth control die-cutting process of the EMI roll material in the structure shown.

[0029] Figure 13 This is a cross-sectional diagram showing the EMI roll material after a second controlled-depth die-cut and separation of waste material during the manufacturing process.

[0030] Figure 14 This is a bottom view after the EMI roll material has undergone a second controlled-depth die-cut and the waste material has been separated during the manufacturing process.

[0031] Figure 15 This is a schematic diagram of the layered explosion structure during the preparation process, where a micro-adhesive carrier film is bonded after the second controlled-depth die-cutting and in preparation for the third controlled-depth die-cutting.

[0032] Figure 16 This is a schematic diagram of the layered explosion structure after the high-viscosity transfer film undergoes a third controlled-depth die-cut during the preparation process.

[0033] Figure 17 This is a schematic diagram of the EMI shielding film mounting structure described in this invention after being mounted onto a flexible circuit board and pressed together.

[0034] Figure 18 This is a schematic diagram illustrating the process effect of peeling off multiple EMI release films at once by removing the high-adhesion transfer film after lamination.

[0035] Label Explanation: 1. High-adhesion transfer film; 11. Positioning hole; 12. Third die-cutting position; 2. Masking film; 21. First die-cutting position; 3. EMI unit array layer; 31. EMI shielding film unit; 32. Shielding film; 33. Surface release film; 34. Protective release film; 35. Second die-cutting position; 36. Main body; 37. Protrusion; 4. Supporting release film; 5. Exposed adhesive area; 6. Limit roller. Detailed Implementation

[0036] 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.

[0037] In the design of FPC for high-end consumer electronics and wearable devices, due to the constraints of compact wiring space and complex mechanical structure, the EMI shielding area is often divided into multiple small (usually less than 3mm wide), narrow U-shaped, and isolated EMI shielding film units. This type of design poses a severe challenge to traditional manufacturing processes, specifically: (1) Single-piece mounting is not feasible: The small U-shaped single-piece EMI auxiliary material structure is fragile and easily deformed and drifted during automatic picking, making it difficult to stably adsorb and accurately position, resulting in extremely low mounting yield; (2) Manual operation is inefficient: If multiple dispersed EMI components are mounted manually one by one, it is not only inefficient and inconsistent, but also significantly increases labor costs; (3) Post-processing is cumbersome: After each independent EMI component is mounted and pressed, the release film on its surface must be removed separately; for arrays containing dozens of points, this operation is time-consuming and prone to omission.

[0038] Therefore, the present invention provides an EMI shielding film mounting structure, referring to... Figure 1 as well as Figure 2 The EMI shielding film mounting structure includes a high-adhesion transfer film 1, a masking film 2, and an EMI unit array layer 3. The high-adhesion transfer film 1 has an adhesive surface. The masking film 2 is disposed on the adhesive surface and includes multiple cutout areas that partially expose the adhesive surface to form multiple exposed adhesive areas 5. The EMI unit array layer 3 includes multiple EMI shielding film units 31. Each EMI shielding film unit 31 includes a shielding film 32 and a surface release film 33 covering the shielding film 32. Each EMI shielding film unit 31 is adhered to the corresponding exposed adhesive area 5 through the surface release film 33.

[0039] In practical applications, based on the above-mentioned EMI shielding film mounting structure, the mounting and peeling of the film can be performed quickly. The specific mounting and peeling methods are as follows: First, the automatic mounting equipment uses a vacuum nozzle to pick up the high-adhesion transfer film 1 from the integrated composite material; then, the equipment's vision system identifies the alignment pattern of the high-adhesion transfer film 1, accurately positions the entire EMI shielding film mounting structure at one time, and mounts it to the target area of ​​the FPC panel. During this process, the initial adhesion and positioning can be achieved by the contact between the pre-set exposed adhesive dots on the high-adhesion transfer film 1 and the FPC panel; next, a hot-pressing process is performed to firmly cure each EMI shielding film unit 31 onto the surface of the FPC panel; finally, after pressing, the surface release film 33 of all the EMI shielding film units 31 adhered to is removed at one time by peeling off the high-adhesion transfer film 1, leaving only the cured shielding film 32 on the FPC.

[0040] Based on this, the present invention uses a high-adhesion transfer film 1 as an integrated skeleton to integrate fragile, dispersed, small, irregularly shaped EMI shielding film units 31 onto the high-adhesion transfer film 1. By adsorbing and positioning the high-adhesion transfer film 1, stable and high-precision mounting of the EMI shielding film units 31 can be achieved, alleviating the problem of difficulty in automatically picking up and positioning single parts, and effectively improving the mounting yield. On this basis, the original single-part mounting and film removal operation that required hundreds of cycles is further compressed into a one-time whole-group mounting and one-time whole-group film removal, which greatly shortens the overall process time and reduces manpower requirements, thereby improving production efficiency.

[0041] As can be seen from the above description, the beneficial effects of the present invention are as follows: by using the composite structure of the high-adhesion transfer film 1 and the shielding film 2, multiple independent EMI shielding film units 31 that were originally dispersed, narrow and easily deformable are integrated into a continuous material. In other words, the originally dispersed and independent small irregular EMI shielding film units 31 are physically integrated into an array of materials that can be operated as a whole, which solves the problems of easy deformation and drift and difficult positioning of individual EMI shielding films 32 due to their fragile structure and small size. Simultaneously, by utilizing the adhesive relationship between the surface release film 33 of the EMI shielding film unit 31 and the exposed adhesive area 5 of the high-adhesion transfer film 1, the precise positioning and temporary fixation of the EMI shielding film unit 31 on the high-adhesion transfer film 1 are achieved. Based on this, after the above-mentioned EMI shielding film mounting structure is pressed onto the flexible circuit board, by peeling off the high-adhesion transfer film 1, the surface release films 33 of all the EMI shielding film units 31 that are attached to it can be removed at once, effectively improving the mounting and film removal efficiency, and solving the problem in the prior art that the surface release film of each independent EMI mounting needs to be removed separately after pressing, which is time-consuming and prone to omission.

[0042] In some embodiments, such as Figure 1As shown, the EMI shielding film mounting structure may further include a carrier release film 4, which is disposed on the side of the EMI unit array layer 3 away from the high-adhesion transfer film 1. It should be noted that before mounting the above-mentioned EMI shielding film mounting structure onto the FPC panel, the carrier release film 4 will be pre-removed for pressing.

[0043] As described above, the release film 4 serves as a continuous substrate, providing mechanical support and protection for the composite structure above in the roll state, preventing misalignment or damage to the EMI shielding film unit 31 array during winding and unwinding, and ensuring continuous roll formation of materials.

[0044] In some embodiments, such as Figure 6 , Figure 7 as well as Figure 8 As shown, the high-adhesion transfer film 1 has a plurality of positioning holes 11, and the plurality of positioning holes 11 are all located on the edge side of the high-adhesion transfer film 1.

[0045] As described above, the positioning hole 11 is set on the edge side of the high-viscosity transfer film 1, which provides a unified reference coordinate system for the depth control die-cutting process, realizes high-precision alignment, eliminates the position deviation of the EMI shielding film unit 31 caused by interlayer offset, and avoids cumulative error.

[0046] In some embodiments, the thickness of the high-adhesion transfer film 1 is 0.05 mm to 0.075 mm, and the adhesive force of the adhesive surface on the high-adhesion transfer film 1 is greater than the peeling force of the surface release film 33.

[0047] As described above, the thickness of the high-adhesion transfer film 1 is set to 0.05mm to 0.075mm to ensure sufficient flexibility and strength to serve as a load-bearing framework. Furthermore, the adhesive force of the high-adhesion transfer film 1 is made greater than the peel force of the release film 33 on the surface of the EMI shielding film unit 31, ensuring that the release film 33 on the surface of all EMI shielding film units 31 can be reliably and completely peeled off in one go when the transfer film is removed after pressing.

[0048] In some embodiments, such as Figure 17 As shown, the EMI shielding film unit 31 includes a main body 36 and a protrusion 37 connected to each other. The main body 36 is U-shaped, and the protrusion 37 is located on the side of the main body 36.

[0049] Accordingly, the present invention also provides a method for preparing an EMI shielding film mounting structure. Figure 3 This is a flowchart illustrating the steps of the preparation method of the EMI shielding film mounting structure described in this invention. (Refer to...) Figure 3 The preparation method includes steps 100 to 108.

[0050] Step 100: Adhere the masking film 2 to the adhesive surface of the high-adhesion transfer film 1; Step 102: Perform a first depth-controlled die-cut on the masking film 2 to form a hollow area, and then peel off the waste material to obtain an initial transfer film with an exposed adhesive area 5 and an adhesive-free masking area; Step 104: The EMI roll material is attached to the initial transfer film, and the EMI roll material is then subjected to a second depth control die-cut to form the EMI unit array layer 3; Step 106: Attach the carrier release film 4 below the EMI unit array layer 3; Step 108: Perform a third depth-controlled die-cut on the high-adhesion transfer film 1, and peel off the edge waste of the high-adhesion transfer film 1 to obtain the EMI shielding film mounting structure.

[0051] For example, the EMI shielding film mounting structure on the main FPC of a smartwatch will be used as an example for illustration. During the material preparation stage, for the 21 U-shaped EMI shielding areas with a width of 1.5mm dispersed on the FPC panel, a 25μm thick high-adhesion transfer film 1 (PI film) with a thickness of 0.075mm and an adhesion strength greater than 4N / cm is first laminated onto it. The PET film (i.e., the shielding film 2) is first die-cut and waste is removed to form 24 square shielding blocks. At the same time, the PET film is removed from the four corners of the transfer film to expose the adhesive dots. Then, the EMI roll is laminated to the back of the above material, and its protective film is removed. After the second depth control die-cutting, the depth is controlled to cut through the EMI layer to 10μm below the surface of the transfer film. After waste removal, an array of EMI shielding film units 31 is formed. Then, a 50μm thick carrier release film 4 is laminated under the adhesive surface of the EMI shielding film unit 31, and a third depth control die-cutting is performed. The depth is controlled to cut through the transfer film to 15μm below the surface of the release film. Finally, a strip integrated material containing 21 independent EMI shielding film units 31 is obtained and wound onto an 80mm wide carrier release film 4 strip.

[0052] Based on this, in the application stage, the automatic reinforcing machine adsorbs the high-adhesion transfer film 1 of the EMI shielding film mounting structure and applies it to the corresponding position of the watch FPC in one go, and achieves initial adhesion and positioning through exposed adhesive dots; then it is hot-pressed for 60 seconds at 180°C and 0.6MPa; after pressing, the operator peels off the high-adhesion transfer film 1 smoothly at an angle of about 70 degrees, and removes the surface release film 33 of all 21 EMI shielding film units 31 in one go within 2 seconds, improving the installation and film removal efficiency by more than 10 times.

[0053] As described above, by the steps of pasting the shielding film, first depth control die-cutting, bonding the EMI roll material, second depth control die-cutting, composite carrier release film 4, and third depth control die-cutting, the dispersed EMI shielding film unit 31 is precisely integrated onto the high-adhesion transfer film 1 through three precision cuts and two waste removals, which facilitates efficient and accurate integrated mounting and film removal in the subsequent process.

[0054] In some embodiments, the EMI roll is subjected to a second depth control die-cut to form an EMI unit array layer 3, which includes: performing a second depth control die-cut on the EMI roll and peeling off the EMI waste on the un-adhesive masking area to form a plurality of arrayed EMI shielding film units 31, so that the EMI shielding film units 31 are located on the exposed adhesive area 5.

[0055] As described above, after the second depth control die-cutting, the EMI waste located on the un-adhesive masking area is peeled off, thereby ensuring that only the EMI shielding film unit 31 located in the exposed adhesive area 5 is accurately retained. Based on this, the present invention completes the graphical arrangement and screening of the EMI shielding film unit 31 and the FPC panel target area in the material preparation stage, providing a basis for subsequent one-time accurate mounting and realizing the precise alignment of the EMI array layout and the EMI area of ​​the FPC panel.

[0056] In some embodiments, the preparation method may further include: punching out positioning holes 11 while performing the first depth control die cutting on the shielding film 2; and using the positioning holes 11 for precise positioning during the second and third depth control die cutting.

[0057] As described above, positioning holes 11 are punched out simultaneously during the first die-cutting process, so that the same set of positioning holes 11 can be used for positioning in subsequent key die-cutting steps. This effectively achieves a unified coordinate reference and high-precision alignment of multi-layer materials during the composite and multiple cutting processes, avoiding the cumulative error caused by multiple positioning reference conversions.

[0058] In some embodiments, the step of attaching the EMI roll material to the initial transfer film includes: obtaining an EMI roll material with the bottom release film removed and the adhesive surface exposed; attaching the EMI roll material to the initial transfer film in roll form using a die-cutting positioning system; wherein the attachment position of the EMI roll material satisfies the following condition: the distance between the EMI roll material and the edge of the positioning hole 11 is greater than or equal to 2 mm.

[0059] As described above, the roll bonding using the die-cutting positioning system avoids the low efficiency of single-piece bonding. At the same time, during bonding, the bonding position meets the minimum distance from the edge of the positioning hole 11, preventing EMI material from covering the positioning hole 11 or getting too close to the edge during lamination. This ensures the positioning accuracy and structural stability of the material in subsequent die-cutting processes, prevents mechanical interference, and avoids process failures caused by material interference.

[0060] In some embodiments, the depth of the second depth control die-cut is controlled to completely break the EMI unit array layer 3 without breaking the high-adhesion transfer film 1; the depth of the third depth control die-cut is controlled to completely break the high-adhesion transfer film 1 without breaking the carrier release film 4.

[0061] As described above, the second depth control die-cutting depth is strictly controlled within the range of cutting through the EMI layer but not cutting the transfer film, and the third depth control die-cutting depth is strictly controlled within the range of cutting through the transfer film but not cutting the carrier release film 4. Through precise Z-axis depth control, the layered processing effect of "cutting the upper layer and keeping the lower layer intact" is achieved, which not only ensures the clarity of the boundaries of each layer of graphics, but also maintains the continuity of the bottom carrier release film 4 and the transfer film.

[0062] To make this application easier to understand, the following is combined with... Figures 1 to 18 An example application is provided.

[0063] In this exemplary application, such as Figure 1 As shown, the EMI shielding film mounting structure of the present invention includes, from top to bottom, the following: The high-adhesion transfer film 1 is a polymer film (such as PET or PI film) with a thickness of 0.05~0.075mm and a high-adhesion pressure-sensitive adhesive surface. Its adhesive force is much greater than the peel force of the release film of the EMI shielding film unit 31.

[0064] The masking film 2 is a 25μm thick film formed by die-cutting onto the adhesive surface of the high-adhesion transfer film 1. Its masking pattern covers areas that do not need to be bonded to the FPC board, while keeping the adhesive surface exposed in areas that need initial bonding and positioning with the FPC. Exposed adhesive dots are provided at the edges of the exposed adhesive areas 5 for initial fixation during installation and to prevent slippage. It should be noted that in practical applications, the masking film can be PET or a similar polymer film.

[0065] The EMI unit array layer 3 consists of multiple independent, small, irregularly shaped EMI shielding film units 31, which are attached to the exposed adhesive area 5 through their respective surface release films 33 according to their precise coordinates corresponding to the FPC panel, thereby accurately reconstructing the EMI layout of the FPC panel on the high-adhesion transfer film 1.

[0066] The support release film 4 is a 50μm thick release film that is attached to the bottom of the entire material. It is used to support and protect the above-mentioned composite structure in the roll state and to provide an adsorption surface for automatic mounting equipment. This layer is kept uncut in the final die-cutting process to ensure the continuity of the material when it is rolled.

[0067] Based on this, in order to obtain the EMI shielding film mounting structure described above, such as Figure 3 As shown, the following preparation method based on multilayer composite and graded depth control die cutting can be adopted: S1: Masking film 2 composite and first depth control die cutting. For example... Figure 4 as well as Figure 5 As shown, a 25μm thick masking film 2 is laminated onto the adhesive surface of a rolled, 75μm thick high-adhesion transfer film 1; subsequently, a first depth-controlled die-cut is performed based on the first die-cutting position 21, and simultaneously, as shown... Figure 6 as well as Figure 7 As shown, positioning holes 11 are punched out simultaneously and the required pattern is cut out; after peeling off the waste material, exposed adhesive areas 5 and non-adhesive masking areas (i.e. areas masked by masking film 2) are formed on the adhesive surface of the high-adhesion transfer film 1 according to the plan.

[0068] S2: EMI shielding film unit 31 array attachment. For example... Figure 8 , Figure 9 , Figure 10 as well as Figure 11 As shown, the EMI roll material, with the protective release film 34 (i.e., the bottom release film) removed and the adhesive surface exposed, is precisely rolled and laminated onto the material treated in S1 using a die-cutting and positioning system. Specifically, during the lamination process, as... Figure 8 as well as Figure 9 As shown, the edge of the EMI roll is at least 3mm from the edge of the finished transfer film strip and at least 2mm from the edge of the positioning hole 11. An adjustable limiting roller 6 is used to ensure alignment, so that the EMI roll covers the adhesive area of ​​the high-adhesion transfer film 1 but does not cover the positioning hole 11; subsequently, as... Figure 11 As shown, remove the protective release film 34 from the EMI adhesive surface, and then, as... Figure 12 As shown, the positioning hole 11 is used to perform a second depth-controlled die-cut at the second die-cutting position 35. This second depth-controlled die-cut must completely break through the EMI layer, but the cutting depth must be strictly controlled to ensure no damage to the high-adhesion transfer film 1 above. After the second depth-controlled die-cut, as shown... Figure 13 as well as Figure 14 As shown, the EMI process border waste located on the adhesive-free area is peeled off, so that the individual EMI shielding film unit 31 is precisely retained in the adhesive area specified by the transfer film, forming an array of EMI shielding film units 31.

[0069] S3: A composite of a release film and a carrier film. (e.g., ...) Figure 15As shown, a 50μm thick release film is laminated as a carrier layer below the adhesive surface of the EMI shielding film unit 31 of the material obtained in S2. This carrier release film 4 must also not cover the positioning hole 11.

[0070] S4: Apply positioning hole 11 again, and perform a third depth control die-cut based on the third die-cutting position 12, such as... Figure 15 As shown, the third depth-controlled die-cutting needs to completely puncture the upper high-adhesion transfer film 1, but the depth must be strictly controlled to ensure that the bottom 50μm thick support release film 4 is not cut; as Figure 16 As shown, after the third depth control die-cutting, the edge waste of the high-adhesion transfer film 1 is peeled off, and finally a strip-shaped precision integrated composite material containing multiple EMI shielding film units 31 is obtained, which is continuously supported by the complete support release film 4 below, and then wound up.

[0071] The EMI shielding film mounting structure prepared above can be used by mounting and peeling the film according to the following usage method: S5: Automatic mounting equipment (such as automatic reinforcing machine) uses a vacuum nozzle to adsorb the high-viscosity transfer film 1 on the upper surface of the EMI shielding film mounting structure, and picks up and separates the entire strip of material from the carrier release film 4 below it. S6: The equipment's vision system identifies the alignment pattern of the high-viscosity transfer film 1 on the material, such as... Figure 17 As shown, the entire EMI shielding film unit 31 array is precisely positioned and mounted onto the target area of ​​the FPC panel in one go. During the mounting process, the pre-set exposed adhesive dots on the high-adhesion transfer film 1 come into contact with the FPC panel to generate initial adhesive force, so as to prevent the material from shifting before subsequent pressing and to ensure that the mounting position is fixed. S7: Perform a hot-pressing process on the mounted FPC panel to firmly bond the EMI shielding film unit 31 to the board surface; S8: After pressing, the high-adhesion transfer film 1 is clamped and peeled off manually or automatically using a fixture; as shown. Figure 18 As shown, based on the extremely high adhesion of the high-adhesion transfer film 1, it can completely remove the surface release film 33 of all the EMI shielding film units 31 that are adhered to during peeling, leaving only a number of small, irregularly shaped EMI shielding film units 31 that have been firmly cured on the FPC board, thereby completing the entire mounting and release film removal process.

[0072] In summary, compared with existing technologies, this invention has achieved significant progress in several aspects: By integrating fragile, small, irregularly shaped EMI shielding film units 31 into a robust strip-shaped set material using a high-adhesion transfer film 1, the problem of automatic picking and mounting of individual units is solved, improving mounting yield. Furthermore, this invention can further compress hundreds of individual unit cycles into a single-set mounting and film removal, effectively shortening process time. Moreover, the relative positions of all EMI shielding film units 31 are determined during the material preparation stage through high-precision die-cutting, eliminating the cumulative error of individual mounting and ensuring extremely high precision and consistency in layout. In addition, by selectively masking and reserving exposed adhesive dots using the masking film 2, reliable initial adhesion and anti-slip properties are achieved during mounting, avoiding improper adhesion. Finally, the material is produced in standard roll form, which can be directly integrated into existing fully automated production lines without equipment modification, powerfully promoting the upgrade of FPC production towards full automation and intelligence.

[0073] In summary, the EMI shielding film mounting structure and its preparation method provided by the present invention are as follows: (1) The present invention provides a precision integrated composite material for finely dispersed U-shaped EMI shielding film 32 and its preparation and mounting method. The present invention is made through a set of precise multi-layer lamination-hole positioning-graded depth control die-cutting processes, which can integrate and fix dozens of independent fine EMI shielding film units 31 according to their precise positions on the FPC panel onto a strip of high-viscosity transfer film 1, forming a physically connected, directly machine-mounted standardized set material. Based on this material, the present invention further provides an automated production method for realizing one-time whole-group mounting and one-time whole-group film removal, thereby transforming the original discrete, inefficient, and difficult production mode into an integrated, efficient, and high-precision assembly line operation. (2) The core of this invention is to construct an integrated and modular material manufacturing system characterized by precision shielding design, multi-layer hole composite, and graded depth control die cutting. It transforms the layout data of FPC design into downstream plug-and-play automated production tools through upstream precision material engineering, fundamentally solving the problems of process feasibility, production efficiency and mounting accuracy faced by micro-shaped electronic components in ultra-high density assembly.

[0074] 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. An EMI shielding film mounting structure, characterized in that, include: High-adhesion transfer film with adhesive side; A masking film is disposed on the adhesive surface of the film. The masking film includes multiple cutout areas, which partially expose the adhesive surface of the film to form multiple exposed adhesive areas. The EMI unit array layer includes multiple EMI shielding film units. Each EMI shielding film unit includes a shielding film and a surface release film covering the shielding film. Each EMI shielding film unit is attached to the corresponding exposed adhesive area through the surface release film.

2. The EMI shielding film mounting structure according to claim 1, characterized in that, It also includes a carrier release film disposed on the side of the EMI unit array layer away from the high-adhesion transfer film.

3. The EMI shielding film mounting structure according to claim 1, characterized in that, The high-adhesion transfer film has multiple positioning holes, all of which are located on the edge side of the high-adhesion transfer film.

4. The EMI shielding film mounting structure according to claim 1, characterized in that, The thickness of the high-adhesion transfer film is 0.05mm to 0.075mm, and the adhesive force of the adhesive surface on the high-adhesion transfer film is greater than the peel force of the surface release film.

5. The EMI shielding film mounting structure according to claim 1, characterized in that, The EMI shielding film unit includes a main body and a protrusion connected to each other. The main body is U-shaped, and the protrusion is located on the side of the main body.

6. A method for preparing an EMI shielding film mounting structure, characterized in that, include: A masking film is pasted onto the adhesive surface of the high-adhesion transfer film; The masking film is first die-cut with controlled depth to form a hollow area. After peeling off the waste material, an initial transfer film with an exposed adhesive area and an adhesive-free masking area is obtained. The EMI roll material is bonded to the initial transfer film, and the EMI roll material is then subjected to a second depth-controlled die-cutting to form an EMI unit array layer; A carrier release film is bonded beneath the EMI unit array layer; The high-adhesion transfer film is subjected to a third controlled-depth die-cut, and the edge waste of the high-adhesion transfer film is peeled off to obtain the EMI shielding film mounting structure.

7. The preparation method according to claim 6, characterized in that, The EMI roll material is subjected to a second controlled-depth die-cutting to form an EMI unit array layer, including: By performing a second depth-controlled die-cut on the EMI roll and peeling off the EMI waste material on the un-adhesive masking area, multiple arrayed EMI shielding film units are formed, so that the EMI shielding film units are located on the exposed adhesive area.

8. The preparation method according to claim 6, characterized in that, Also includes: While performing the first depth-controlled die-cutting of the shielding film, positioning holes are punched out; During the second and third depth control die cutting, precise positioning is achieved by using the positioning holes.

9. The preparation method according to claim 8, characterized in that, The step of laminating the EMI roll material onto the initial transfer film includes: Obtain EMI rolls with the bottom release film removed and the adhesive surface exposed; The EMI roll material is bonded to the initial transfer film in roll form using a die-cutting and positioning system; wherein the bonding position of the EMI roll material satisfies the following condition: the distance between the EMI roll material and the edge of the positioning hole is greater than or equal to 2 mm.

10. The preparation method according to claim 6, characterized in that, The depth of the second controlled-depth die-cut is controlled to completely break the EMI unit array layer without breaking the high-adhesion transfer film; the depth of the third controlled-depth die-cut is controlled to completely break the high-adhesion transfer film without breaking the carrier release film.

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