Circuit board pressing process method

Abstract

The invention discloses a circuit board pressing process method, and relates to the technical field of printed circuit board manufacturing. The circuit board pressing process method comprises the following steps: S1, separately performing release treatment on a positioning nail and a lining; s2, bushings subjected to release treatment are mounted in the mounting holes of the bottom plate, and the bottom ends of the positioning nails subjected to release treatment are inserted into the bushings of the bottom plate; s3, a first Teflon gasket, the target number of core plates and prepregs and a second Teflon gasket are sequentially arranged on the positioning nail in a sleeving mode, so that stack-up pre-typesetting is completed; and S4, the lining obtained after release treatment is mounted in the mounting hole of the cover plate, the laminated structure is covered with the cover plate, and the top end of the positioning nail is inserted into the lining of the cover plate. Teflon gaskets are additionally arranged on the two sides of the stacking structure in combination with release treatment, it is jointly guaranteed that a positioning system composed of the positioning nails and the linings is clean and smooth in the whole pressing process, labor and cost are efficiently saved, and meanwhile high alignment precision and product quality of pressing are reliably guaranteed.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board manufacturing technology, and in particular to a circuit board lamination process method. Background Technology

[0002] In the field of printed circuit board manufacturing, as electronic products develop towards higher density and higher performance, the number of layers on circuit boards is constantly increasing, placing extreme demands on the alignment accuracy of the lamination process. Currently, high-end lamination processes in the industry generally employ a positioning system consisting of high-precision positioning pins and bushings mounted on the bottom cover plate to ensure the alignment accuracy of the multilayer core board and prepreg stack during the lamination process.

[0003] However, the accuracy of this positioning system directly depends on the tooling precision of the positioning pins and bushings. In actual production, this pair of components needs to be reused multiple times. After each pressing, a small amount of cured or semi-cured resin will inevitably remain on the surface of the positioning pins; at the same time, under the influence of high temperature and pressure, the molten resin can easily seep into and fill the inner hole of the bushing. As the positioning pins are removed from the bushings, uneven resin residue will be left on the inner wall of the hole. Due to the extremely small manufacturing tolerances of the positioning pins and bushings themselves, the fit tolerance of the entire positioning system is only 0.017 mm. Any micron-level residue will prevent the reusable positioning pins and bushings from fitting directly and smoothly, thus failing to meet the initial assembly requirements of high-precision pressing.

[0004] To address this issue, current production processes require operators to spend considerable time manually cleaning residual adhesive from the surfaces of the positioning pins and the inner holes of the bushings before each layout. This method is not only labor-intensive and time-consuming, leading to low production efficiency, but also inconsistent with the cleaning effectiveness, posing a risk of damaging the precision tool surfaces. Furthermore, to ensure tool accuracy, the positioning pins and bushings must be dimensionally inspected using a go / no-go gauge before each use; components that fail the inspection are discarded, further increasing production costs and material waste. Summary of the Invention

[0005] The purpose of this invention is to provide a circuit board lamination process method to maintain the cleanliness and dimensional accuracy of the positioning pins and bushings during the lamination process, while reducing production costs and material waste.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A circuit board lamination process includes:

[0008] S1. Perform release treatment on the positioning pins and bushings respectively;

[0009] S2. Install the release-treated bushing in the mounting hole of the base plate, and insert the bottom end of the release-treated positioning pin into the bushing of the base plate.

[0010] S3. Insert the first Teflon gasket, the target number of core boards and prepregs, and the second Teflon gasket sequentially onto the positioning pin to complete the pre-layout of the stacked structure.

[0011] S4. Install the release-treated bushing in the mounting hole of the cover plate, and cover the cover plate on top of the stacked structure, so that the top of the positioning pin is inserted into the bushing of the cover plate.

[0012] As an optional solution to the circuit board lamination process, the method for releasing the positioning pins in S1 includes:

[0013] After immersing the positioning pin in a water-soluble release agent for a first preset time and drying it, a release agent is sprayed onto its surface to form a separation film.

[0014] As an alternative to the circuit board bonding process, when the positioning pins are reusable, a step of cleaning the positioning pins is included before the release process.

[0015] As an alternative to the circuit board lamination process, the method for cleaning the positioning pins is as follows: using a vibratory grinder, the surface of the positioning pins is ground and cleaned using a mixed abrasive.

[0016] As an optional embodiment of the circuit board lamination process, the mixed abrasive includes a cleaning abrasive, a polishing abrasive, and a self-cleaning abrasive. The cleaning abrasive is used to remove surface residue, the polishing abrasive is used for surface polishing, and the self-cleaning abrasive is used to clean the polishing abrasive and the cleaning abrasive.

[0017] As an optional solution to the circuit board lamination process, the ratio of the amount of the cleaning abrasive, the polishing abrasive, and the self-cleaning abrasive is 4:4:2.

[0018] As an optional solution to the circuit board lamination process, the main body shape of the cleaning abrasive is a polyhedron; the main body shape of the polishing abrasive is a sphere or an ellipsoid; and the main body shape of the self-cleaning abrasive is a combination of a polyhedron and an arc-shaped surface.

[0019] As an optional solution to the circuit board lamination process, the method for releasing the bushing in S1 includes:

[0020] After cleaning the inner wall of the bushing, a release agent is sprayed to form a separation film.

[0021] As an optional solution to the circuit board lamination process, in step S3, after the first Teflon gasket is fitted and before the core board and the prepreg are placed, the first separator and the first steel plate are laid in sequence.

[0022] After the core board and the prepreg are stacked and before the second Teflon gasket is installed, the second steel plate is placed and the second isolation piece is laid.

[0023] As an alternative to the circuit board lamination process, the first insulating material includes a first kraft paper and a first high-temperature cloth, with the first high-temperature cloth laid between the first kraft paper and the first steel plate;

[0024] The second insulating element includes a second high-temperature cloth and a second kraft paper, with the second high-temperature cloth laid between the second steel plate and the second kraft paper.

[0025] The beneficial effects of this invention are:

[0026] The circuit board lamination process provided by this invention, through release treatment of the positioning pins, forms a stable separation film on their surface, effectively preventing the adhesion of resin residue. This avoids the time-consuming and labor-intensive manual cleaning required in traditional processes, thus improving production efficiency. This release treatment, combined with the physical isolation measure of adding Teflon gaskets on both sides of the stacked structure, ensures the cleanliness and smooth operation of the positioning system composed of the positioning pins and bushings throughout the lamination process, avoiding dimensional deviations and tool damage caused by residual adhesive. Simultaneously, the release treatment of the bushings on the base plate and cover plate ensures the stable maintenance of the entire positioning system's tolerance. Ultimately, while efficiently saving labor and costs, it reliably guarantees high alignment accuracy and product quality in the PCB lamination process. Attached Figure Description

[0027] Figure 1 This is a schematic flowchart of the circuit board lamination process provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the positioning structure of the circuit board during lamination provided in an embodiment of the present invention.

[0029] In the picture:

[0030] 1. Base plate; 2. First kraft paper; 3. First high-temperature cloth; 4. First steel plate; 5. Pre-layout of the stacked structure; 6. Second steel plate; 7. Second high-temperature cloth; 8. Second kraft paper; 9. Cover plate; 10. Positioning nail. Detailed Implementation

[0031] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0032] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0033] Unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and connections within two components or interactions between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0034] Unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0036] In existing circuit board lamination processes, the core board is punched to form slots and round holes, while the prepreg is drilled to form round holes. Positioning pins include PINs and round pins. The core board and prepreg are sequentially fitted with PINs through the slots, stacked according to the MI (Mean Injection) stacking sequence, and steel plates, a base plate, and a cover plate are placed on the upper and lower surfaces respectively to secure the PINs. Subsequently, curing and bonding are completed in a press under specific temperature and pressure according to a set program. After lamination, a PIN ejector is used to punch out the PINs, and then the steel plate and the prepreg are disassembled sequentially; this process is repeated cyclically.

[0037] The process has the following main defects: (1) During the pressing process, the PIN directly penetrates the core board and the prepreg, forming a series structure. Under hot pressing conditions, the prepreg melts, causing the resin to flow and adhere tightly to the side wall and arc surface of the PIN. After cooling and solidification, it strongly adheres to the bushing, kraft paper, etc., making it difficult to punch out smoothly when removing the PIN. At the same time, the residual adhesive causes the PIN size to exceed the tolerance range, making it unusable and increasing the cost of consumables. (2) As a key component for fixing the PIN, the bushing is affected by the molten resin seeping into the PIN surface during the pressing process, resulting in a large amount of adhesive accumulating in the upper part of its inner hole. During the PIN removal operation, the PIN cannot be smoothly removed due to the obstruction of the adhesive. When it is hit, local stress concentration occurs, causing the bushing to undergo plastic deformation or damage, resulting in a high scrap rate and affecting the continuity of production and tool life. The above problems seriously affect the stability and production efficiency of the pressing process and bring additional maintenance and material costs.

[0038] To solve the above-mentioned technical problems, this embodiment provides a circuit board lamination process in which a positioning system is formed by high-precision positioning pins and bushings installed on the base plate and cover plate during circuit board lamination, so as to ensure the alignment accuracy of the multilayer core board and prepreg stack during the lamination process.

[0039] like Figure 1 and Figure 2 As shown, the circuit board lamination process includes the following steps:

[0040] S1. Perform release treatment on the positioning pin 10 and the bushing respectively.

[0041] To ensure that the positioning system consisting of the positioning pin 10 and the bushing reduces the amount of resin adhesive adhering to the positioning pin 10 and the bushing during the circuit board lamination process, the positioning pin 10 and the bushing are first subjected to release treatment before positioning.

[0042] In one embodiment, the method for releasing the positioning pin 10 in S1 includes: immersing the positioning pin 10 in a water-soluble release agent for a first preset time and drying it, and then spraying a release agent on its surface to form a release film.

[0043] By first immersing the positioning pin 10 in a water-soluble release agent and then drying it, and then spraying it with a release agent, a composite separation film is formed. This composite separation film can effectively reduce the surface energy of the positioning pin 10 and enhance its heat resistance, thereby preventing the adhesion of molten resin during the pressing process. This ensures that the positioning pin 10 can be easily detached from the bushing and sheet after cooling, avoiding problems such as difficulty in removing the pin, dimensional deviations, and tool damage caused by adhesive. At the same time, it extends the service life of the positioning pin 10, reduces cleaning and maintenance time and production costs, and improves the stability and efficiency of the pressing process.

[0044] Specifically, pour the water-soluble release agent into a container, and then completely immerse the positioning pins 10 below the surface of the water-soluble release agent. The water-soluble release agent is an environmentally friendly mold release agent that uses water as a dispersion medium, in which the active ingredients are dispersed or emulsified. Its complex composition aims to form an effective separation film, while also being easy to clean and possessing low volatile organic compound properties.

[0045] For example, the first preset time is 0.5 hours to 1.5 hours. When soaking the positioning pins 10, 100 positioning pins 10 are soaked in 1 liter of water-soluble release agent.

[0046] In the mold release agent application process, the positioning pins 10, which have undergone dipping and drying, are neatly placed in a plastic storage box. Then, DL1000 type release agent is selected as the mold release agent and sprayed evenly and comprehensively onto the surface of the positioning pins 10 using a spray gun in an atomized form, ensuring no blind spots. After spraying, allow it to stand for approximately 5 minutes until a uniform white film layer appears on the surface of the positioning pins 10, indicating that the release film has formed and stabilized. At this point, it can be used in the pressing process.

[0047] When the positioning pin 10 is to be reused, a cleaning step is included before the release treatment. This step aims to thoroughly remove any residual cured resin adhesive from the surface of the positioning pin 10 and to increase its specific surface area and surface activity by moderately polishing the surface, thereby creating optimal conditions for the uniform adhesion and stable film formation of the subsequent release agent.

[0048] In one embodiment, the method for cleaning the positioning pin 10 is as follows: a vibratory grinder is used to grind and clean the surface of the positioning pin 10 using a mixed abrasive. The vibratory grinder uses high-frequency vibration to create complex relative motion between the abrasive and the positioning pin 10, enabling it to act on the entire complex surface of the positioning pin 10 (including sidewalls, threads, head, etc.) without blind spots, ensuring that residual resin is completely and efficiently removed, far surpassing the efficiency and effectiveness of manual cleaning. While removing residual adhesive, the mixed abrasive also performs a minor abrasion on the metal surface. This process not only removes dirt but, more importantly, removes the surface oxide layer, increases the specific surface area, and forms a micro-anchoring structure that is more conducive to the adhesion of the release agent, laying a solid foundation for the subsequent formation of a firm and uniform separation film.

[0049] For example, in an 8-inch vibratory grinder, 100 positioning pins 10 are used as the optimized load for each processing run, and a grinding time of 2 to 3 hours is set. This combination of parameters has been verified to meet cleaning requirements. Determining the load quantity is crucial. If too many positioning pins 10 are used at once, it will weaken the effective contact and relative movement between the abrasive and the pin surface, resulting in uneven cleaning or even residue. Conversely, if too few are used, effective mutual grinding cannot be achieved, and the processing capacity per unit time will be reduced, affecting overall efficiency.

[0050] Of course, in other embodiments, the positioning pin 10 can also be cleaned by ultrasonic cleaning.

[0051] In one embodiment, the mixed abrasive includes a cleaning abrasive, a polishing abrasive, and a self-cleaning abrasive. The cleaning abrasive is used to remove surface residue, the polishing abrasive is used for surface polishing, and the self-cleaning abrasive is used to clean both the polishing and cleaning abrasives. The cleaning abrasive is typically sharper and harder, directly attacking and removing stubborn resin residue from the surface of the positioning pin 10 through cutting and scraping. The polishing abrasive is typically smoother and of moderate hardness, smoothing and finishing any micro-scratches that the cleaning abrasive may leave, reducing surface roughness. The self-cleaning abrasive, typically of high hardness and a specific shape, continuously collides and rubs against the cleaning and polishing abrasives in the mixed abrasive, scraping off the adhesive particles adhering to their surfaces, restoring them to sharpness and smoothness. This allows the surface of the positioning pin 10 to undergo the entire process "from adhesive removal to polishing" simultaneously in one step, and the mixed abrasive itself maintains continuous and efficient cleaning capabilities, avoiding efficiency loss and secondary contamination caused by abrasive contamination.

[0052] In one embodiment, the ratio of cleaning abrasive, polishing abrasive, and self-cleaning abrasive is 4:4:2. The four parts cleaning abrasive and four parts polishing abrasive form an equal proportion, ensuring efficient removal of residual adhesive while simultaneously achieving surface finishing, thus achieving a precise balance between cleaning power and polishing quality. The two parts self-cleaning abrasive serve as the core of system maintenance, effectively preventing the main abrasive from being passivated by adhesive particles, ensuring continuous and stable cleaning efficiency throughout the entire grinding cycle. This optimized ratio ultimately produces significant comprehensive technical benefits in improving cleaning efficiency, ensuring surface treatment quality, extending abrasive lifespan, and ensuring batch consistency.

[0053] In one embodiment, the main body of the cleaning abrasive is a polyhedron, utilizing its sharp edges to achieve efficient cutting and scraping. The main body of the polishing abrasive is a sphere or ellipsoid, utilizing its smooth curved surface for rolling and polishing. The main body of the self-cleaning abrasive is a combination of a polyhedron and an arc-shaped surface, possessing both the scraping ability of a flat surface and the rolling performance of an arc surface.

[0054] For example, the cleaning abrasive is a triangular prism with an edge length of 4mm, the polishing abrasive is a sphere with a radius of 3mm, and the self-cleaning abrasive is a cylinder with a height of 5mm and a bottom radius of 4mm.

[0055] In one embodiment, the method for releasing the bushing in S1 includes: cleaning the inner wall of the bushing and then spraying a release agent to form a separation film. Pre-cleaning the inner wall of the bushing thoroughly removes residual cured resin from the previous pressing process, restoring the original dimensional accuracy of the inner hole and clearing physical obstacles for the subsequent formation of a uniform and complete separation film. The subsequently sprayed release agent forms a low surface energy and heat-resistant separation film on the clean inner hole surface. This film effectively prevents direct contact between the molten resin and the metal hole wall during the next pressing process, fundamentally avoiding secondary adhesion and accumulation of resin adhesive. This ensures that the positioning pin 10 can still smoothly detach from the bushing after pressing, solving not only the problem of difficult pin removal and bushing deformation due to residual adhesive blockage but also extending the service life of the bushing. Furthermore, it transforms the previously cumbersome and inefficient manual cleaning of the inner hole into a highly efficient and reliable preventative treatment, thus improving the overall stability and production efficiency of the pressing and positioning system.

[0056] For example, a precision steel wire brush with a diameter of 4mm is selected as the cleaning tool. The inner wall of the bushing is cleaned three times using a rotating or reciprocating motion to ensure thorough removal of residual resin without damaging the substrate. After cleaning, DL1000 release agent is immediately sprayed evenly 360° onto the inner wall of the bushing using a dedicated spray gun. During spraying, the spray gun axis is kept parallel to the bushing centerline at a distance of 50mm to 80mm, and sprayed continuously for 2 to 3 seconds at a spray pressure of 0.5MPa to 0.8MPa to ensure a completely covered wet film layer is formed on the inner surface. After static curing, a continuous and uniform release film should form on the surface of the bushing's inner wall, without any flow marks or accumulation. At this point, the bushing is ready for use in the pressing process.

[0057] S2. Install the release-treated bushing in the mounting hole of the base plate 1, and insert the bottom end of the release-treated positioning nail 10 into the bushing of the base plate 1.

[0058] The outer diameter of the bushing is slightly larger than the inner diameter of the mounting hole. Before installing the bushing, ensure that the inner wall of the mounting hole is free of burrs, oil, or residue. Using a dedicated press or hydraulic press, vertically and smoothly press the release-treated bushing into the mounting hole. During pressing, ensure that the bushing is aligned with the axis of the mounting hole to prevent tilting. After pressing, the bushing should be firmly embedded in the mounting hole without any loosening or rotation.

[0059] Align the bottom end of the release-processed positioning pin 10 with the bushing inner hole that has been fixed on the base plate 1.

[0060] It should be noted that the positioning pin 10 includes a PIN pin and a round pin. The PIN pin includes two symmetrical planes and two symmetrical arc surfaces. The shape of the inner hole of the bushing into which the PIN pin is inserted is adapted to the shape of the PIN pin. The inner hole of the bushing into which the round pin is inserted is a round hole.

[0061] The number of mounting holes on the base plate 1 and the cover plate 9 is adapted to the number of positioning pins 10. For example, the positioning pins 10 include four PIN pins and four round pins. The base plate 1 and the cover plate 9 are each provided with eight mounting holes and eight bushings. The inner hole shape of four bushings is adapted to the outer peripheral shape of the PIN pins, and the inner hole of the other four bushings is a round hole.

[0062] S3. Insert the first Teflon gasket, the target number of core boards and prepreg sheets, and the second Teflon gasket into the positioning pin 10 in sequence to complete the pre-layout of the stacked structure 5.

[0063] Before inserting the first Teflon gasket onto the positioning pin 10, fifteen sheets of kraft paper are placed on the base plate 1. The kraft paper has positioning holes that match the shape of the positioning pin 10. The kraft paper passes through these holes and is placed on top of the base plate 1. The kraft paper serves to buffer and insulate heat, preventing excessive pressure on the intermediate laminated structure during pressing and thus avoiding damage; it also ensures more even heat distribution during pressing.

[0064] In step S3, after the first Teflon gasket is installed and before the core board and prepreg are placed, the first spacer and the first steel plate 4 are laid sequentially. After the core board and prepreg are stacked and before the second Teflon gasket is installed, the second steel plate 6 is placed and the second spacer is laid. Specifically, the first spacer includes a first kraft paper 2 and a first high-temperature cloth 3, with the first high-temperature cloth 3 laid between the first kraft paper 2 and the first steel plate 4. The second spacer includes a second high-temperature cloth 7 and a second kraft paper 8, with the second high-temperature cloth 7 laid between the second steel plate 6 and the second kraft paper 8.

[0065] Before layout, fifteen sheets of kraft paper are placed on the base plate 1. Then, a first Teflon gasket of the corresponding specification is inserted onto the positioning pin 10. The inner diameter of the first Teflon gasket matches the outer diameter of the positioning pin 10, and its outer diameter matches the outer diameter of the bushing. Next, the first kraft paper 2 and the first high-temperature cloth 3 are placed sequentially on the first Teflon gasket. After placing the first steel plate 4 at the bottom of the laminated structure, copper foil, prepreg, core board, prepreg, and copper foil are inserted according to the MI stacking sequence, with one copper foil on each side. The prepreg and core board in the middle are placed sequentially according to the target quantity. After layout is completed, the second steel plate 6 is placed, followed by the second high-temperature cloth 7 and the second kraft paper 8. Then, a second Teflon gasket of the corresponding specification is inserted onto the positioning pin 10, and finally, fifteen more sheets of kraft paper are placed.

[0066] High-temperature fabric, with its PTFE coating, establishes a high-temperature resistant, non-stick barrier between the steel plate and the Teflon gasket, effectively preventing resin from penetrating the steel plate surface. Kraft paper, with its fibrous structure, absorbs any trace amounts of escaping resin and buffers pressure, while its breathability helps release volatile substances. The synergistic effect of these two materials protects the steel plate surface, reduces maintenance costs, improves the quality of sheet forming by optimizing the hot-pressing interface, and extends the service life of the kraft paper, creating an efficient and economical multi-layered isolation solution.

[0067] It should be noted that the steel plate must be cleaned before placing it to prevent contamination of the copper foil.

[0068] The Teflon gasket isolates the bushing from the stacked layout, effectively preventing the molten resin from the prepreg from contaminating the upper and lower surfaces of the bushing and the positioning pin 10.

[0069] S4. Install the release-treated bushing in the mounting hole of the cover plate 9, and cover the cover plate 9 on top of the stacked structure, so that the top of the positioning nail 10 is inserted into the bushing of the cover plate 9.

[0070] After the core board and prepreg are stacked on the positioning pin 10, lift the cover plate 9 so that the inner hole of the bushing on it is precisely aligned with the top of the positioning pin 10. Then lower the cover plate 9 smoothly so that the top of the positioning pin 10 is inserted into the bushing of the cover plate 9 until the cover plate 9 contacts the stacked surface.

[0071] The circuit board lamination process provided in this embodiment, by performing a release treatment on the positioning pins 10, forms a stable separation film on their surface, effectively preventing the adhesion of resin residue. This avoids the time-consuming and labor-intensive manual cleaning required in traditional processes, thus improving production efficiency. This release treatment, combined with the physical isolation measure of adding Teflon gaskets on both sides of the stacked structure, ensures the cleanliness and smoothness of the positioning system composed of the positioning pins 10 and bushings throughout the lamination process, avoiding dimensional deviations and tool damage caused by residual adhesive. At the same time, the release treatment on the bushings on the base plate 1 and the cover plate 9 ensures that the tolerance of the entire positioning system is maintained stably. Ultimately, while efficiently saving labor and costs, it reliably guarantees high alignment accuracy and product quality in the PCB lamination process.

[0072] The above description is only a preferred embodiment of the present invention. For those skilled in the art, there will be changes in the specific implementation and application scope based on the ideas of the present invention. The content of this specification should not be construed as a limitation of the present invention.

Claims

1. A circuit board lamination process, characterized in that, include: S1. Perform release treatment on the positioning pin (10) and the bushing respectively; S2. Install the release-treated bushing in the mounting hole of the base plate (1) and insert the bottom end of the release-treated positioning pin (10) into the bushing of the base plate (1); S3. Insert the first Teflon gasket, the target number of core boards and prepregs, and the second Teflon gasket into the positioning pin (10) in sequence to complete the pre-layout of the stack (5). S4. Install the release-treated bushing in the mounting hole of the cover plate (9) and cover the cover plate (9) over the stacked structure, so that the top of the positioning pin (10) is inserted into the bushing of the cover plate (9).

2. The circuit board lamination process according to claim 1, characterized in that, The method for releasing the positioning pin (10) in S1 includes: After immersing the positioning pin (10) in a water-soluble release agent for a first preset time and drying it, a release agent is sprayed onto its surface to form a separation film.

3. The circuit board lamination process according to claim 2, characterized in that, When the positioning pin (10) is to be reused, a step of cleaning the positioning pin (10) is included before the release process.

4. The circuit board lamination process according to claim 3, characterized in that, The method for cleaning the positioning pin (10) is as follows: a vibratory grinder is used to grind and clean the surface of the positioning pin (10) using a mixed abrasive.

5. The circuit board lamination process according to claim 4, characterized in that, The mixed abrasive includes cleaning abrasive, polishing abrasive, and self-cleaning abrasive. The cleaning abrasive is used to remove surface residue, the polishing abrasive is used for surface polishing, and the self-cleaning abrasive is used to clean the polishing abrasive and the cleaning abrasive.

6. The circuit board lamination process according to claim 5, characterized in that, The ratio of the amount of the cleaning abrasive, the polishing abrasive, and the self-cleaning abrasive is 4:4:

2.

7. The circuit board lamination process according to claim 5, characterized in that, The main body shape of the cleaning abrasive is a polyhedron; the main body shape of the polishing abrasive is a sphere or ellipsoid; the main body shape of the self-cleaning abrasive is a combination of a polyhedron and an arc-shaped surface.

8. The circuit board lamination process according to claim 1, characterized in that, The method for releasing the bushing in S1 includes: After cleaning the inner wall of the bushing, a release agent is sprayed to form a separation film.

9. The circuit board lamination process according to claim 1, characterized in that, In S3, after the first Teflon gasket is installed and before the core board and the prepreg are placed, the first isolation piece and the first steel plate (4) are laid in sequence. After the core board and the prepreg are stacked and before the second Teflon gasket is installed, the second steel plate (6) is placed and the second isolation piece is laid.

10. The circuit board lamination process according to claim 9, characterized in that, The first insulating component includes a first kraft paper (2) and a first high-temperature cloth (3), with the first high-temperature cloth (3) laid between the first kraft paper (2) and the first steel plate (4); The second insulating element includes a second high-temperature cloth (7) and a second kraft paper (8), with the second high-temperature cloth (7) laid between the second steel plate (6) and the second kraft paper (8).

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