TWI869027B - De-capping method of printed circuit board - Google Patents

Abstract

A de-capping method of a printed circuit board is provided, which includes: providing a first inner core substrate; forming two metal barrier structures and two laser cutting grooves on the first inner core substrate; printing a peelable printing ink in a printing area inside the two metal barrier structures; disposing at least one second inner core substrate on one side of the first inner core substrate and stacking them together through a laminating adhesive layer to form a multi-layer circuit board structure; using two de-capping punches of a plate de-capping device to respectively align with positions of the two laser cutting grooves, and automatically performing a de-capping operation on the multi-layer circuit board structure towards a direction of the two laser cutting grooves so that the multilayer circuit board structure forms a de-capping opening.

Description

Printed Circuit Board Decapping Method

The present invention relates to a decapping method, in particular to a decapping method for a printed circuit board.

In the prior art, after the decapping operation in the manufacturing process of a multi-layer circuit board, the edge of the decapping opening may be mixed with the semi-cured glue due to the strippable ink, so the strippable ink may be difficult to remove during cleaning. In addition, in the prior art, the angle of the decapping opening edge is affected by the laser, which causes the problem of chemical exchange, resulting in a long stripping time for the strippable ink, and there is a risk of residual strippable ink, which may affect the electrical characteristics of the finished circuit board.

Furthermore, the existing technology often relies on manual labor for decapping of multi-layer printed circuit boards (PCBs). However, manual labor often has the problem of uncontrollable quality in decapping of printed circuit boards. For example, different operators often use different forces for decapping of printed circuit boards. Or, the same operator may use different forces for decapping of printed circuit boards under different physical conditions. Therefore, the existing technology has the problem of uncontrollable quality of decapping or reduced yield (for example, decapping residue problem) for decapping of printed circuit boards.

Furthermore, the decapping operation based on existing technology mainly relies on manual work, so it is difficult to carry out mass production, and thus it is difficult to meet customer needs.

The technical problem to be solved by the present invention is to provide a method for removing the cover of a printed circuit board in view of the shortcomings of the existing technology.

In order to solve the above technical problems, one of the technical solutions adopted by the present invention is to provide a method for removing the cover of a printed circuit board, which includes: providing a first inner core substrate; forming two protruding metal blocking structures on a side surface of the first inner core substrate, and forming two laser cutting grooves recessed from the side surface on the first inner core substrate; wherein the inner sides of the two metal blocking structures are A printing area is formed on the first inner core substrate, and two laser cutting grooves are formed adjacent to the inner sides of the two metal blocking structures; a strippable printing ink is printed on the printing area on the inner sides of the two metal blocking structures on the first inner core substrate, and the strippable printing ink can be further filled into the two laser cutting grooves during the printing process; at least one second inner core substrate is formed on the inner side of the two metal blocking structures; The core substrate is arranged on a side of the first inner core substrate far from the two metal blocking structures and the strippable printing ink, and the at least one second inner core substrate is stacked with the first inner core substrate through a bonding adhesive layer, and a circuit layer addition operation is performed to form a multi-layer circuit board structure; wherein the two metal blocking structures and the strippable printing ink are buried in the multi-layer circuit board. In the circuit board structure; using two decapping punches of a plate decapping device to align the positions of the two laser-cut grooves respectively, a decapping operation is automatically performed from the surface of the multi-layer circuit board structure located on the second inner core substrate to the direction of the two laser-cut grooves; and the two decapping punches are removed to form a decapping opening in the multi-layer circuit board structure, and a decapping structure is also formed.

Preferably, the two metal blocking structures are formed by a metal etching operation, and the two laser cut grooves are formed by a laser cutting operation.

Preferably, during the process of the sheet material decapping device blindly removing the multi-layer circuit board structure, the two decapping punches partially overlap with the two laser-cut grooves respectively, and each of the decapping punches does not penetrate the multi-layer circuit board structure after the decapping operation is completed.

Preferably, the sheet material decapping device comprises a longitudinal guide member and a decapping mold member movably disposed on the longitudinal guide member; wherein the decapping mold member comprises two decapping punches, and the decapping mold member can move up and down along a longitudinal direction on the longitudinal guide member to perform the decapping operation.

Preferably, the decapping mold component comprises a mold body, two decapping punches and a fixed plate; wherein the two decapping punches are spaced and fixedly arranged on the bottom surface of the mold body, the mold body can be movably arranged on the longitudinal guide component through the fixed plate, and can move up and down along the longitudinal direction, and the decapping mold component can drive the two decapping punches to move toward the multi-layer circuit board structure through the driving of the longitudinal guide component to perform the decapping operation.

Preferably, the decapping mold component further includes two retractable pressing plates, which are respectively retractably arranged on the bottom surface of the mold body and form a rectangular area around the two decapping punches.

Preferably, the uncovering opening is formed by being recessed from the top surface of the multi-layer circuit board structure toward the two metal blocking structures, and the uncovering opening does not cover the two metal blocking structures; wherein the uncovering structure includes part of the first inner core substrate and part of the second inner core substrate, but does not include the two metal blocking structures.

Preferably, the decapping method of the printed circuit board further comprises: removing the decapping structure from the position where the strippable printing ink is located through the two laser-cut grooves in the multi-layer circuit board structure.

Preferably, the method for removing the cover of the printed circuit board further comprises: performing a cleaning operation to remove the remaining strippable printing ink at the bottom of the removal opening.

Preferably, the side wall of each metal blocking structure facing the uncovering opening is defined as a metal blocking side wall, and the side wall of each laser cutting groove facing the uncovering opening is defined as a laser cutting side wall; wherein the metal blocking side wall and the laser cutting side wall have an angle between 120 degrees and 150 degrees.

One of the beneficial effects of the present invention is that the method for removing the cover of the printed circuit board provided by the present invention can be achieved by "providing a first inner core substrate; forming two protruding metal blocking structures on a side surface of the first inner core substrate, and forming two laser cutting grooves recessed from the side surface on the first inner core substrate; wherein the inner sides of the two metal blocking structures are formed on the first inner core substrate to surround the inner surface of the first inner core substrate; A printing area is formed on the inner side of the two metal barrier structures, and the two laser cutting grooves are formed adjacent to each other; a peelable printing ink is printed on the printing area on the inner side of the two metal barrier structures on the first inner core substrate, and the peelable printing ink can be further filled into the two laser cutting grooves during the printing process; at least one second inner core substrate is arranged far away from the first inner core substrate On one side of the two metal blocking structures and the strippable printing ink, the at least one second inner core substrate and the first inner core substrate are stacked together through a bonding adhesive layer, and a circuit layer addition operation is performed to form a multi-layer circuit board structure; wherein the two metal blocking structures and the strippable printing ink are buried in the multi-layer circuit board structure; two decapping punches of a plate decapping device are used to respectively The technical solution of "aligning the positions of the two laser cutting grooves, performing a decapping operation from the surface of the multi-layer circuit board structure located on the second inner core substrate in the direction of the two laser cutting grooves; and removing the two decapping punches to form a decapping opening in the multi-layer circuit board structure" can solve the problem of strippable printing ink being difficult to strip, and can realize the automated decapping operation of the multi-layer circuit board.

To further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are only for reference and description and are not used to limit the present invention.

Z: Multi-layer circuit board structure

1: First inner core substrate

D: Metal blocking structure

D1: Metal blocking side wall

C: Laser cutting groove

C1: Laser cutting sidewalls

α: Angle of intersection

I: Strippable printing ink

R: Printing area

2: Second inner core substrate

3: Outer metal pad

PP: Laminating adhesive layer

TH:Through hole

PTH: Plated Through Hole

O: Remove the cover and open the mouth

O1: Uncovered structure

L1~L8: Line

F: Plate removing device

F1: Longitudinal guide component

F2: Remove the cover of the mold components

F21: Mold body

F22: Decapping punch

F23: Telescopic pressure plate

F24: Fixed plate

Figure 1 is a schematic diagram of step S110 of the method for removing the cover of a printed circuit board according to an embodiment of the present invention.

Figure 2 is a schematic diagram of step S120 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

Figure 3 is a schematic diagram of step S130 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

Figure 4 is a schematic diagram of step S140 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

Figure 5 is a schematic diagram of step S150 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

Figure 6 is a schematic diagram of step S160 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

Figure 7 is a schematic diagram of step S170 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

Figure 8 is a schematic diagram of step S180 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

Figure 9 is a partial enlarged schematic diagram of area IX in Figure 8.

Figure 10 is a schematic diagram of a plate cover removal device according to an embodiment of the present invention.

The following is a specific embodiment to illustrate the implementation method disclosed by the present invention. The technical personnel in this field can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments. The details in this specification can also be modified and changed based on different viewpoints and applications without deviating from the concept of the present invention. In addition, the attached drawings of the present invention are only for simple schematic illustration and are not depicted according to actual size. Please note in advance. The following implementation method will further explain the relevant technical content of the present invention in detail, but the disclosed content is not used to limit the scope of protection of the present invention.

[How to remove the cover of printed circuit boards]

Referring to FIGS. 1 to 8 , the present invention provides a decapping method of a printed circuit board, and in particular, provides a decapping method of a semi-bent printed circuit board, which includes steps S110, S120, S130, S140, S150, S160, S170, and S180. It should be noted that the sequence of the steps and the actual operation method in the present invention can be adjusted according to the needs, and are not limited to those in the present embodiment. The decapping method of the printed circuit board of the present invention can provide additional operations before, during, or after each step, and some of the operations described can be replaced, eliminated, or relocated to realize additional implementations of the method. The following describes the decapping method of a semi-printed circuit board in conjunction with Figures 1 to 8.

Figure 1 is a schematic diagram of step S110 of the method for removing the cover of a printed circuit board according to an embodiment of the present invention.

The step S110 includes: providing a first inner core substrate 1 (also called core). Both side surfaces of the first inner core substrate 1 are formed with a metal copper foil layer. In this embodiment, the two side surfaces of the first inner core substrate 1 are respectively formed with a line L5 and a line L6.

The step S110 further includes: providing at least one second inner core substrate 2, and placing it on one side of the first inner core substrate 1. Both side surfaces of the second inner core substrate 2 are formed with a metal copper foil layer. In this embodiment, the two side surfaces of the second inner core substrate 2 are respectively formed with a line L3 and a line L4.

Figure 2 is a schematic diagram of step S120 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

The step S120 includes: performing a metal etching operation to form two protruding metal dam structures D (metal dam structures) on the surface of one side of the first inner core substrate 1.

The step S120 further includes: performing a laser cutting operation to form two laser cut grooves C (laser cut grooves) recessed from the side surface on the first inner core substrate 1.

The inner sides of the two metal blocking structures D surround a printing area R on the first inner core substrate 1, and the two laser cutting grooves C are formed by being recessed from the side surface of the first inner core substrate 1. The positions of the two laser cutting grooves C correspond to the printing area R and are formed adjacent to the inner sides of the two metal blocking structures D. In other words, the first inner core substrate 1 forms a laser cutting groove C adjacent to each metal blocking structure D on the inner side.

It is worth mentioning that the two metal blocking structures D and the two laser cutting grooves C in FIG. 2 are viewed in a cross-section. If viewed from a top view, the metal blocking structure D can be, for example, two long strip-shaped dams to surround the printing area R, but the present invention is not limited thereto. The metal blocking structure D can also be, for example, a continuous ring structure (not shown) to surround the printing area R.

More specifically, the metal etching operation is to perform etching (such as wet etching or dry etching) on the metal copper foil layer on the first inner core substrate 1 to remove part of the metal copper foil layer, thereby forming the two protruding metal blocking structures D on the first inner core substrate 1.

In some embodiments of the present invention, in each of the metal barrier structures D, the material of the metal barrier structure D is copper metal, and a cross-section of the metal barrier structure D is roughly rectangular (as shown in FIG. 2 ) or trapezoidal (not shown). The width of the metal barrier structure D is between 30 microns and 600 microns, preferably between 30 microns and 175 microns, and particularly preferably between 50 microns and 155 microns. The height H of the metal barrier structure D is between 15 microns and 300 microns, and preferably between 17.5 microns and 280 microns.

In some embodiments of the present invention, the laser cutting operation is to use a laser cutting machine (such as a PCB laser cutting machine) to perform laser cutting on the first inner core substrate 1 to remove part of the material of the first inner core substrate 1.

Thereby, the first inner core substrate 1 can form two concave laser cutting grooves C. In this embodiment, the shape of each laser cutting groove C is roughly V-shaped, but the present invention is not limited to this. In addition, the depth of each laser cutting groove C can be adjusted according to the design requirements of the product.

Figure 3 is a schematic diagram of step S130 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

The step S130 includes: performing a printing operation to print a strippable printing ink I on the printing area R inside the two metal blocking structures D on the first inner core substrate 1, and the strippable printing ink I can be further filled into the two laser-cut grooves C during the printing process.

The decapping method of the printed circuit board of the embodiment of the present invention can prevent the strippable printing ink I from overflowing during the printing process through the design of the metal blocking structure D and the laser cutting groove C, and can also help improve the stripping efficiency and cleaning effect of the strippable printing ink I in the subsequent stripping operation.

In terms of material types, the strippable printing ink I can be, for example, commonly used strippable ink for PCB, gold finger protection ink, anti-plating ink, PI or PFG, etc., but not limited to materials that can assist separation. Furthermore, the step S130 includes: drying or baking the strippable printing ink I in the shade so that the strippable printing ink I is in a solidified state, which is conducive to subsequent stripping operations.

Figure 4 is a schematic diagram of step S140 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

The step S140 includes: placing the at least one second inner core substrate 2 on a side of the first inner core substrate 1 away from the two metal blocking structures D and the strippable printing ink I, and laminating the at least one second inner core substrate 2 and the first inner core substrate 1 together through a bonding adhesive layer PP (such as Prepreg film).

The step S140 further includes: adding two outer layers of circuits (such as circuit L2 and circuit L7) on both sides of the first inner core substrate 1 and the second inner core substrate 2 through a circuit layer adding operation to form a multi-layer circuit board structure Z; and the step S140 further includes: forming a through hole TH (through hole) penetrating the multi-layer circuit board structure Z.

The strippable printing ink I is printed on the printing area R inside the two metal blocking structures D on the first inner core substrate 1, and the strippable printing ink I can be further filled into the two laser-cut grooves C during the printing process.

More specifically, in this embodiment, the two metal blocking structures D formed on the first inner core substrate 1 and the strippable printing ink I are embedded in the multi-layer circuit board structure Z.

Figure 5 is a schematic diagram of step S150 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

The step S150 includes: performing an electroplating operation to form an electroplating layer on the inner wall of the through hole TH, thereby forming the through hole TH into an electroplating through hole PTH (plating through hole); and performing an outer layer circuit operation to form two outer layer circuits (such as circuit L1 and circuit L8) on the two side surfaces of the multi-layer circuit board structure Z, and forming an outer layer metal pad 3 on the outer layer circuit (such as the outer layer metal pad 3 on the bottom surface circuit L8), but the present invention is not limited thereto.

In this embodiment, the electroplated through hole PTH penetrates the first inner core substrate 1 and the at least one second inner core substrate 2, and is located on one side of the two metal blocking structures D and the strippable printing ink I, but does not penetrate or overlap the two metal blocking structures D and the strippable printing ink I.

Figure 6 is a schematic diagram of step S160 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

The step S160 includes: using a plate decapping device F to perform a decapping operation on the multi-layer circuit board structure Z.

Please refer to FIG. 10 , the sheet material removing device F comprises a longitudinal guide member F1 and a removing mold member F2 movably disposed on the longitudinal guide member F1. The removing mold member F2 can move up and down along a longitudinal direction on the longitudinal guide member F1.

Furthermore, the longitudinal guide member F1 may be, for example, a slide cylinder.

The decapping mold component F2 includes a mold body F21 and two decapping punches F22. In this embodiment, the decapping mold component F2 further includes two retractable pressing plates F23 (Figure 10 only shows one retractable pressing plate, and the other is set at the rear side and is covered), but it is not limited to this.

In this embodiment, the mold body F21 is roughly in the shape of a hexahedron (such as a cuboid or a cube), but the present invention is not limited thereto.

The mold body F21 can be movably (slidably) disposed on the longitudinal guide member F1 through a fixed plate F24, and can move up and down along the longitudinal direction. Accordingly, the decapping mold member F2 can be moved toward the multi-layer circuit board structure Z by driving the longitudinal guide member F1.

The two decapping punches F22 are spaced and fixedly disposed on the bottom surface of the mold body F21, and the two decapping punches F22 are configured to perform decapping operations on the multi-layer circuit board structure Z (as shown in FIG6).

More specifically, the sheet material removing device F drives the removing mold component F2 to move toward the surface of the multi-layer circuit board structure Z located on the second inner core substrate 2 (i.e., the top surface of the multi-layer circuit board structure Z) through the longitudinal guide component F1.

The two retractable pressing plates F23 are roughly rectangular plate-shaped, and are spaced and retractably arranged on the bottom surface of the mold body F21, and are located on both sides of the two decapping punches F22, and roughly surround the two decapping punches F22 to form a rectangular area, but the present invention is not limited thereto.

In the decapping operation, the two decapping punches F22 of the sheet decapping device F are configured to align with the positions of the two laser cutting grooves C, and blindly pick up from the surface of the multi-layer circuit board structure Z located on the second inner core substrate 2 in the direction of the two laser cutting grooves C. In the process of blind picking, the two decapping punches F22 partially overlap with the two laser cutting grooves C, and partially remove the strippable printing ink I filled in the laser cutting grooves C. In addition, the blind picking depth of each decapping punch F22 is less than the thickness of the multi-layer circuit board structure Z, that is, each decapping punch F22 does not penetrate the multi-layer circuit board structure Z after the decapping operation is completed.

Please continue to refer to FIG. 6. In this embodiment, each decapping punch F22 is not aligned with the center line position of the corresponding laser cutting groove C for blind picking. Each decapping punch F22 is slightly offset from the printing area R by the center line of the corresponding laser cutting groove C to facilitate the subsequent decapping operation, but the present invention is not limited thereto.

Furthermore, when the two decapping punches F22 perform decapping operations on the multi-layer circuit board structure Z, the two retractable pressing plates F23 can be retractably secured to the top surface of the multi-layer circuit board structure Z, and secured to the portion of the top surface of the multi-layer circuit board structure Z other than the portion to be decapped.

Figure 7 is a schematic diagram of step S170 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

The step S170 includes: moving the two decapping punches F22 of the sheet decapping device F in a direction away from the multi-layer circuit board structure Z by driving the longitudinal guide member F1, thereby removing the two decapping punches F22 from the multi-layer circuit board structure Z, so that the multi-layer circuit board structure Z can form a decapping opening O, and further form a decapping structure O1.

More specifically, the uncovering opening O is formed by being recessed from the top surface of the multi-layer circuit board structure Z (i.e., the surface located on the second inner core substrate 2) toward the two metal blocking structures D. Furthermore, the scope of the uncovering opening O does not cover the two metal blocking structures D.

In addition, the decapping structure O1 is waste generated after the decapping operation, and the decapping structure O1 includes part of the first inner core substrate 1 and part of the second inner core substrate 2, but does not include two metal blocking structures D.

Figure 8 is a schematic diagram of step S180 of the method for removing the cover of the printed circuit board according to an embodiment of the present invention.

The step S180 includes: removing the decapping structure O1 from the position where the strippable printing ink I is located through two laser-cut grooves C in the multi-layer circuit board structure Z.

The step S180 further includes: performing a cleaning operation to remove the remaining strippable printing ink I at the bottom of the decapping opening O.

In this embodiment, the cleaning operation is to use a chemical agent to clean the residual ink at the bottom of the decapping opening O. The chemical agent may be, for example, a chemical agent containing a modified alcohol ether, but the present invention is not limited thereto.

As shown in FIG9 , the side wall of each metal blocking structure D facing the uncovering opening O is defined as a metal blocking side wall D1, and the side wall of each laser cutting groove C facing the uncovering opening O is defined as a laser cutting side wall C1. There is an angle α between the metal blocking side wall D1 and the laser cutting side wall C1, and the angle α is preferably between 120 degrees and 150 degrees, and particularly preferably between 130 degrees and 140 degrees. For example, the angle α can be, for example, 135 degrees.

Based on the angle α between the metal blocking side wall D1 and the laser cutting side wall C1, a flushing space can be formed. Thus, the chemical agent can fully exchange the chemical solution in the flushing space between the metal blocking side wall D1 and the laser cutting side wall C1, thereby fully removing the residual ink.

[Beneficial effects of the embodiment]

One of the beneficial effects of the present invention is that the method for removing the cover of the printed circuit board provided by the present invention can be achieved by "providing a first inner core substrate; forming two protruding metal blocking structures on a side surface of the first inner core substrate, and forming two laser cutting grooves recessed from the side surface on the first inner core substrate; wherein the inner sides of the two metal blocking structures surround a printing area on the first inner core substrate, and the two The laser cutting groove is formed adjacent to the inner side of the two metal blocking structures; a strippable printing ink is printed on the printing area on the inner side of the two metal blocking structures on the first inner core substrate, and the strippable printing ink can be further filled into the two laser cutting grooves during the printing process; at least one second inner core substrate is arranged on the first inner core substrate away from the two metal blocking structures and the strippable printing ink. The ink is applied to one side of the substrate, and the at least one second inner core substrate is laminated with the first inner core substrate through a bonding adhesive layer, and a circuit layer adding operation is performed to form a multi-layer circuit board structure; wherein the two metal blocking structures and the strippable printing ink are embedded in the multi-layer circuit board structure; two decapping punches of a plate decapping device are respectively aligned with the positions of the two laser cutting grooves, and the positions of the multi-layer circuit board structure are removed. A decapping operation is performed on the surface of the second inner core substrate in the direction of the two laser-cut grooves; and the two decapping punches are removed so that the multi-layer circuit board structure forms a decapping opening, and a decapping structure is formed in addition. The technical solution solves the problem that the strippable printing ink is difficult to remove after the decapping operation of the multi-layer circuit board, and reduces the possibility of the strippable printing ink residue, and can realize the automated decapping operation of the multi-layer circuit board.

The above disclosed contents are only the preferred feasible embodiments of the present invention, and do not limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made by using the contents of the specification and drawings of the present invention are included in the scope of the patent application of the present invention.

Z: Multi-layer circuit board structure

1: First inner core substrate

D: Metal blocking structure

C: Laser cutting groove

I: Strippable printing ink

2: Second inner core substrate

3: Outer metal pad

PP: adhesive layer

PTH: Plated Through Hole

L1~L8: Line

F: Plate removing device

F22: Decapping punch

F23: Telescopic pressure plate

Claims (10)

A method for removing the cover of a printed circuit board, comprising: Providing a first inner core substrate; Forming two protruding metal blocking structures on a side surface of the first inner core substrate, and forming two laser cutting grooves recessed from the side surface on the first inner core substrate; wherein the inner sides of the two metal blocking structures surround a printing area on the first inner core substrate, and the two laser cutting grooves are formed adjacent to the inner sides of the two metal blocking structures; Printing a strippable printing ink on the printing area on the inner sides of the two metal blocking structures on the first inner core substrate, and the strippable printing ink can be further filled into the two laser cutting grooves during the printing process; At least one second inner core substrate is arranged on a side of the first inner core substrate away from the two metal blocking structures and the strippable printing ink, and the at least one second inner core substrate is stacked with the first inner core substrate through a bonding adhesive layer, and a circuit layering operation is performed to form a multi-layer circuit board structure; wherein the two metal blocking structures and the strippable printing ink are buried in the multi-layer circuit board structure; Using two decapping punches of a plate decapping device to align the positions of the two laser cutting grooves respectively, a decapping operation is automatically performed from the surface of the multi-layer circuit board structure located on the second inner core substrate to the direction of the two laser cutting grooves; and The two decapping punches are removed so that the multi-layer circuit board structure forms a decapping opening and also forms a decapping structure. A method for removing the cover of a printed circuit board as described in claim 1, wherein the two metal blocking structures are formed by a metal etching operation, and the two laser cutting grooves are formed by a laser cutting operation. A method for removing covers from a printed circuit board as described in claim 1, wherein, during the process of blindly removing the multi-layer circuit board structure by the plate removing device, the two removing covers punches partially overlap with the two laser-cut grooves respectively, and each of the removing covers punches does not penetrate the multi-layer circuit board structure after the removing operation is completed. A method for removing covering of a printed circuit board as described in claim 1, wherein the board removing device comprises a longitudinal guide member and a removing covering mold member movably disposed on the longitudinal guide member; wherein the removing covering mold member comprises two removing covering punches, and the removing covering mold member can move up and down along a longitudinal direction on the longitudinal guide member to perform the removing covering operation. A method for removing a printed circuit board as described in claim 4, wherein the removing mold component comprises a mold body, two removing punches and a fixed plate; wherein the two removing punches are spaced and fixedly arranged on the bottom surface of the mold body, and the mold body can be movably arranged on the longitudinal guide component through the fixed plate and can be moved up and down along the longitudinal direction, and the removing mold component can drive the two removing punches to move toward the direction of the multi-layer circuit board structure by driving the longitudinal guide component to perform the removing operation. A method for removing the cover of a printed circuit board as described in claim 5, wherein the removing mold component further includes two retractable pressing plates, which are respectively retractably arranged on the bottom surface of the mold body and form a rectangular area around the two removing punches. A method for removing a printed circuit board as described in claim 5, wherein the removing opening is formed by being recessed from the top surface of the multi-layer circuit board structure toward the two metal blocking structures, and the removing opening does not cover the two metal blocking structures; wherein the removing structure includes a portion of the first inner core substrate and a portion of the second inner core substrate, but does not include the two metal blocking structures. The decapping method for a printed circuit board as described in claim 1 further comprises: Removing the decapping structure from the position of the strippable printing ink through the two laser-cut grooves in the multi-layer circuit board structure. The method for removing the cover of a printed circuit board as described in claim 8 further comprises: Performing a cleaning operation to remove the remaining strippable printing ink at the bottom of the removal opening. A method for removing the cover of a printed circuit board as described in claim 9, wherein the side wall of each of the metal blocking structures facing the removing opening is defined as a metal blocking side wall, and the side wall of each of the laser cutting grooves facing the removing opening is defined as a laser cutting side wall; wherein the metal blocking side wall and the laser cutting side wall have an angle between 120 degrees and 150 degrees.