V-CUT processing method of rigid-flex printed circuit board with surface flexible board layer

Abstract

The invention discloses a V-CUT processing method of a rigid-flex printed circuit board with a flexible board layer on the surface, which comprises the following processing steps of: pre-enlarging the flexible board layer, forming an extension area, manufacturing a pattern to form a flexible board, pre-enlarging the rigid board layer, manufacturing the rigid board, integrally stacking and laminating, attaching a single-sided flexible copper-clad plate on the surface of the flexible board, and manufacturing a surface compensation pattern. Manufacturing a solder resist pattern layer on the surface of the rigid board, manufacturing a guide groove in the extension area, and performing V-CUT processing and micro-etching processing to form a rigid-flexible combined board; an extension area is arranged on a machining plate, an auxiliary compensation pattern and a guide groove are manufactured, the effects of guide cutting, auxiliary alignment and transition cutting on V-CUT machining are achieved, a single-face flexible copper-clad plate is adopted to replace an original covering film layer, a cutting compensation pattern is manufactured, the problems of pulling, wire drawing and cutter rolling of a V-CUT cutter and a polyimide material are solved, and the machining quality of the V-CUT cutter is improved. And high-precision and high-quality V-CUT processing of the rigid-flex printed circuit board with the flexible board layer on the surface is realized.

Description

Technical Field

[0001] The invention relates to the field of circuit board design and processing, and in particular to a V-CUT processing method for a rigid-flexible board with a surface flexible board layer. Background Art

[0002] Rigid-Flex PCB (also known as rigid-flex PCB or hard-soft PCB) has the support performance of rigid board and the bendability of flexible board, which can be flexibly installed, has high reliability and a wide range of application scenarios. Therefore, rigid-flex PCB is used in more and more fields.

[0003] In some cases where there are special requirements for electrical signal transmission, a rigid-flexible board with a flexible board located on the surface layer appears. That is, the flexible board and the rigid board are located on one side of the laminated structure respectively, while the asymmetric structure or the structure where rigid boards are arranged on both sides of the flexible board, this type of rigid-flexible board is generally called a rigid-flexible board with a surface flexible board layer.

[0004] If V-CUT processing is required for the rigid-flexible board with a flexible board layer on the surface, since the flexible board is on the surface layer, V-CUT directly cutting one side of the flexible board is prone to problems such as wire drawing, pulling, and curling. Moreover, since such rigid-flexible boards are asymmetric laminated structures, the difference in material expansion and contraction properties between the flexible board and the rigid board can easily cause problems such as board bending and warping in the rigid board area. V-CUT is prone to problems such as inaccurate alignment, inaccurate cutting, and insufficient cutting depth of the flexible board. Furthermore, if the product is designed without V-CUT positioning holes on the board surface, the cutting accuracy of the V-CUT will be further affected.

[0005] Based on the above background and problems, it is necessary to provide a new V-CUT processing method for a rigid-flexible board with a surface flexible board layer. Summary of the invention

[0006] The present invention aims to solve the V-CUT processing of a rigid-flexible board with a surface flexible board layer. The prior art is prone to V-CUT processing of the flexible board layer, which causes wire drawing, pulling, and curling, and the depth is insufficient and the precision is insufficient. A V-CUT processing method for a rigid-flexible board with a surface flexible board layer is provided. The rigid-flexible board includes a flexible board and a rigid board in a laminated structure. The flexible board is located on one side surface of the rigid board. The surface of the rigid-flexible board is designed with a V-CUT cutting line for making a V-CUT cutting groove.

[0007] The processing method comprises the following steps: S10: taking a flexible board layer, pre-enlarging the size of the flexible board layer according to the design size, forming an extended area distributed on one side of the flexible board layer, and making a circuit pattern on the surface of the flexible board as a whole to form a flexible board; The boundary position between the flexible board layer and the extended area is a boundary line; S20: taking a rigid board layer, pre-enlarging the rigid board layer accordingly according to the extended area, and making a circuit pattern on the surface of the rigid board to form a rigid board; S30: stacking and pressing the flexible board and the rigid board to form a pressed board; S40: attaching a single-sided flexible copper-clad laminate to the surface of the flexible board on the laminated board, wherein the copper layer of the single-sided flexible copper-clad laminate is located on the outer surface; Taking the V-CUT cutting line as the center line, a surface compensation pattern is formed on the copper layer, wherein the width of the surface compensation pattern is greater than the maximum width of the opening of the V-CUT cutting groove; Making a solder resist pattern layer on the rigid board surface of the laminate to form a pattern board as a whole; S50: With the V-CUT cutting line as the center line, a guide groove is made for the surface compensation pattern of the extended area of ​​the graphic board, and the graphic board is V-CUT processed to form a V-CUT cutting groove to form a V-CUT board; S60: performing micro-etching on the V-CUT board to form the rigid-flex board.

[0008] Furthermore, the surface compensation pattern is divided into a guide groove compensation pattern and a cutting compensation pattern; the guide groove compensation pattern is located within the extension area and is a trapezoidal pattern from the boundary line to the board edge.

[0009] Furthermore, the circuit pattern on the surface of the flexible board includes a flexible board compensation pattern, and the flexible board compensation pattern and the guide groove compensation pattern are distributed in corresponding layers to each other.

[0010] Furthermore, the rigid board circuit pattern includes a rigid board compensation pattern, the rigid board compensation pattern takes the V-CUT cutting line as the center line, and the width is greater than the maximum opening width of the V-CUT cutting groove of the rigid board.

[0011] Furthermore, the guide groove is cut from the plate edge to the extended area to form a "V"-shaped groove, the bottom of the "V"-shaped groove is connected to the V-CUT cutting line, and the cutting is performed by milling cutter cutting or die punching.

[0012] Furthermore, the V-CUT processing is to cut in along the direction of the guide groove and perform V-CUT processing, and the V-CUT processing is double-sided V-CUT processing.

[0013] Furthermore, the depth of the V-CUT cutting groove formed by the double-sided V-CUT processing and located on one side of the flexible board is greater than the depth of the V-CUT cutting groove located on one side of the rigid board.

[0014] Furthermore, the micro-etching process is to stick a dry film layer on one side of the rigid board, expose it, and then perform the micro-etching process.

[0015] Furthermore, after the micro-etching process is completed, the V-CUT board is cleaned with a strong alkali.

[0016] Furthermore, the strong alkaline cleaning treatment is to clean the V-CUT board after the micro-etching treatment using a NaOH solution or a KOH solution or a film stripping solution.

[0017] The technical solution of the present invention forms a guiding cutting, auxiliary alignment and transition cutting function for V-CUT processing by setting an extension area on the processing plate and making auxiliary compensation patterns and guide grooves in the extension area, and adopts a single-sided flexible copper-clad laminate to replace the original covering film layer, and uses the copper layer of the single-sided flexible copper-clad laminate to make a cutting compensation pattern. The cutting compensation pattern can effectively provide a transition layer and a compression layer for the single-sided copper-clad laminate dielectric layer and the flexible board, and effectively prevent the V-CUT tool and the single-sided copper-clad laminate dielectric layer and the flexible board from pulling, drawing and rolling the polyimide material. In addition, auxiliary micro-etching, strong alkali cleaning and other treatments can achieve high-precision and high-quality V-CUT processing of the rigid-flexible board with the surface flexible board layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0019] Figure 1 Schematic diagram of the process flow of an embodiment of the present invention; Figure 2 A schematic diagram of the planar structure of a graphic board formed by processing in an embodiment of the present invention; Figure 3 Embodiments of the present invention Figure 2 Schematic diagram of the AA cross-section structure; Figure 4 Embodiments of the present invention Figure 2 Schematic diagram of BB cross-section structure; Figure 5It is a schematic diagram of the planar structure of the guide slot plate formed by processing in an embodiment of the present invention; Figure 6 Embodiments of the present invention Figure 5 Schematic diagram of CC cross-section structure; Figure 7 A schematic diagram of the planar structure of a V-CUT board formed by processing in an embodiment of the present invention; Figure 8 Embodiments of the present invention Figure 7 Schematic diagram of DD cross-section structure; Fig. 9 It is a schematic diagram of the planar structure of a rigid-flexible board formed by processing according to an embodiment of the present invention.

[0020] Description of Figure Numbers: Label name Label name 10 Graphics tablet 220 Rigid board 110 V-CUT cutting line 2210 Second circuit layer 120 Extended area 2220 Rigid board dielectric layer 130 Junction 2230 The third circuit layer 2310Y Guide groove compensation pattern 2240 Solder mask pattern layer 2310Q Cutting compensation graphics 2210B Flexible board compensation pattern 2320 Single-sided flexible copper clad laminate dielectric layer 20 Guide slot plate 2230B Rigid board compensation pattern 240 Guide slot 2320 Single-sided flexible copper clad laminate dielectric layer 30 V-CUT Board 210 Flexible board 310 V-CUT cutting groove 2110 First circuit layer 310G Rigid board V-CUT cutting groove 2120 Flexible board dielectric layer 40 Rigid-Flex PCB The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with the implementation methods and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0023] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0024] See also Figure 1 , Figure 1 Schematic diagram of the process flow of an embodiment of the present invention.

[0025] The V-CUT processing method of the rigid-flexible board with a surface flexible board layer provided in this embodiment is as follows Figure 1The process is described in detail step by step as follows.

[0026] See also Figure 1 , Figure 3 and Figure 4 ; Figure 2 A schematic diagram of the planar structure of a graphic board formed by processing in an embodiment of the present invention; Figure 3 Embodiments of the present invention Figure 2 Schematic diagram of the AA cross-section structure; Figure 4 Embodiments of the present invention Figure 2 Schematic diagram of the BB cross-section structure.

[0027] In this embodiment, a V-CUT processing method for a rigid-flexible board having a surface flexible board layer is provided, wherein the rigid-flexible board includes a flexible board and a rigid board in a laminated structure, wherein the flexible board is located on one side surface of the rigid board to form a structure of a surface flexible board layer, and a V-CUT cutting line 110 is designed on the surface of the rigid-flexible board to form a V-CUT cutting groove.

[0028] Since the flexible board is made of polyimide material, and the covering film layer attached to the surface of the flexible board is also made of polyimide material, it is tougher and more difficult to process than the epoxy resin material of the rigid board. When the rigid-flexible board with a flexible board layer on the surface is processed by V-CUT, the V-CUT knife cuts the polyimide material, which is prone to pulling and wiredrawing, resulting in incomplete processing or even tearing of the flexible board layer. In addition, the structure with the flexible board on one side and the rigid board on the other side is asymmetrical, and the materials on the two sides expand and shrink differently, which is prone to board bending and warping during processing. Inaccurate positioning may occur during V-CUT processing, resulting in inaccurate cutting. Therefore, it is necessary to provide corresponding solutions.

[0029] The processing steps are: Step S10: Take the flexible board layer, including Figure 3 The flexible board dielectric layer 2120 and the surface copper layer shown in the figure are pre-enlarged according to the design size to form an extension area 120 distributed on one side of the flexible board layer. The junction position between the flexible board layer and the extension area is the junction line 130, and the flexible board surface circuit pattern is made as a whole, that is, Figure 3 The first circuit layer 2110 shown in FIG. 2 forms a flexible board 210, such as Figure 3 The first circuit layer 2110 and the flexible board dielectric layer 2120 are shown.

[0030] The extended area 120 and the original processed board are an integral whole, that is, the original processed board is pre-enlarged in the direction of one edge of the V-CUT cutting. During the subsequent V-CUT processing, the extended area 120 cuts into the original processed board, which plays a role in guiding the cutting, assisting the alignment, and transitional cutting of the original processed board; and the extended area 120 is provided with an auxiliary compensation pattern, which will be described in detail below.

[0031] Step S20: Take a rigid board layer, such as Figure 3 The rigid board dielectric layer 2220 and the rigid board surface copper layer shown in the figure are pre-enlarged accordingly according to the extension area 120, and the rigid board surface circuit pattern is made, that is, Figure 3 The second circuit layer 2210 and the third circuit layer 2230 shown in FIG. 2 form a rigid board 220, such as Figure 3 As shown, the rigid board 220 includes a second circuit layer 2210 , a rigid board dielectric layer 2220 and a third circuit layer 2230 .

[0032] In this embodiment, the rigid board circuit pattern includes a rigid board compensation pattern 2230B, which takes the V-CUT cutting line 110 as the center line and has a width greater than the maximum opening width of the V-CUT cutting groove of the rigid board 220 .

[0033] Similarly, the rigid board also includes an extended area 120, and the rigid board is provided with a compensation pattern 2230B, which can match the surface compensation pattern of the subsequent single-sided flexible copper clad board on the one hand, and increase the matching of the cutting conditions of the double-sided V-CUT; on the other hand, the compensation pattern 2230B forms a buffer transition layer for V-CUT processing, reduces the damage of V-CUT to the rigid board substrate, improves processing accuracy, and is more suitable for the production of high-precision circuit board products.

[0034] Step S30: The flexible board 210 and the rigid board 220 are stacked and pressed together to form a pressed board.

[0035] Step S40: A single-sided flexible copper-clad laminate is attached to the surface of the flexible board of the press board 10. The single-sided flexible copper-clad laminate is made of Figure 3 The single-sided flexible copper-clad laminate shown is composed of a dielectric layer 2320 and a copper layer, and the copper layer of the single-sided flexible copper-clad laminate is located on the outer surface; with the V-CUT cutting line 110 as the center line, a surface compensation pattern is made on the copper layer, and the width of the surface compensation pattern is greater than the maximum opening width of the V-CUT cutting groove, that is, the width of the opening position of the V-CUT cutting groove.

[0036] This embodiment adopts a single-sided copper clad laminate to replace the original covering film design, and can use the single-sided flexible copper clad laminate dielectric layer 2320 of the single-sided copper clad laminate to replace the original covering film layer, and use the copper layer to make a surface compensation pattern to provide cutting protection and cutting transition layer for the single-sided flexible copper clad laminate dielectric layer 2320 and the flexible board 210 for V-CUT cutting processing; a glue layer (generally an acrylic glue layer, epoxy resin glue layer, or polyimide glue layer) can be provided on the side where the single-sided flexible copper clad laminate and the flexible board 210 are pressed and attached to facilitate the combination of the single-sided flexible copper clad laminate and the flexible board 210, and can also be made in the form of a single-sided flexible copper clad laminate by etching away the copper layer on one side of the double-sided flexible copper clad laminate.

[0037] In this embodiment, the surface compensation pattern is divided into a guide groove compensation pattern 2310Y and a cutting compensation pattern 2310Q; the guide groove compensation pattern 2310Y is located within the extension area 120 and is a trapezoidal pattern from the boundary line 130 to the board edge.

[0038] The guide groove compensation pattern 2310Y and the cutting compensation pattern 2310Q are connected to form a surface compensation pattern together, wherein the guide groove compensation pattern 2310Y paves the copper layer conditions for the subsequent production of the guide groove, and the cutting compensation pattern 2310Q is important in the V-CUT processing to provide a transition layer and a compression layer for cutting the single-sided copper-clad laminate dielectric layer 2320 and the flexible board 210, which can effectively prevent the V-CUT tool and the single-sided copper-clad laminate dielectric layer 2320 and the flexible board 210 from pulling, drawing, and rolling the polyimide material.

[0039] The surface circuit pattern of the flexible board 210 includes a flexible board compensation pattern 2210B (such as Figure 4 As shown), the flexible board compensation pattern 2210B and the guide groove compensation pattern are distributed in corresponding layers to each other.

[0040] For high-precision processing, a compensation pattern 2210B may be further provided on the flexible board 210, or a compensation pattern 2210B may be provided on each circuit pattern layer of the flexible board, so as to provide a processing transition effect for each layer and improve the processing precision of each layer.

[0041] Subsequently, a solder resist pattern layer 2240 is formed on the surface of the rigid board 220 of the laminate to form a pattern board 10 as a whole; the solder resist pattern layer 2240 can further protect the surface of the rigid board 220 .

[0042] See also Figure 5 , Figure 6 , Figure 7 and Figure 8 ,; Figure 5 It is a schematic diagram of the planar structure of the guide slot plate formed by processing in an embodiment of the present invention; Figure 6Embodiments of the present invention Figure 5 Schematic diagram of CC cross-section structure; Figure 7 A schematic diagram of the planar structure of a V-CUT board formed by processing in an embodiment of the present invention; Figure 8 Embodiments of the present invention Figure 7 Schematic diagram of the DD cross-section structure.

[0043] S50: With the V-CUT cutting line 110 as the center line, a guide groove 240 is made for the surface compensation pattern of the extended area 120 of the graphic board 10, and the graphic board 10 is V-CUT processed to form a V-CUT cutting groove 310, thereby forming a V-CUT board 30.

[0044] The length of the guide groove 240 is less than or equal to the length of the extended area 120. On the one hand, the guide groove 240 can give a certain regularity and guiding effect to the effective area of ​​the original processing board during V-CUT processing, and play a certain auxiliary positioning role when the board is bent or warped. On the other hand, if the board edge of the processing board is not provided with a V-CUT positioning hole, the entire board is in a state of being simply clamped (or semi-clamped) by the equipment, and a certain error may occur in the positioning at this time. The guide groove 240 can better play a guiding and auxiliary positioning role.

[0045] In this embodiment, the guide groove 240 is cut from the board edge to the extended area by milling with a milling cutter or punching with a die to form a “V”-shaped groove, and the bottom of the “V”-shaped groove is connected to the V-CUT cutting line 110 .

[0046] It is worth mentioning that if high-precision circuit board products are produced, milling can be used for processing, and at this time, compensation patterns can be set for the circuit layers inside the flexible board 210 and the rigid board 220 to provide transition layers for each layer and improve the processing accuracy of each layer, thereby improving the overall processing accuracy. If the processing accuracy requirements are normal, mold punching can be used for processing, which helps to improve processing efficiency.

[0047] In this embodiment, the V-CUT processing is to cut in along the guide groove 240 and perform V-CUT processing, and the V-CUT processing is double-sided V-CUT processing; if a one-time double-sided V-CUT processing is adopted, the flatness of the circuit board and the balance of conditions on both sides are required to be higher. If a single-sided to single-sided double-sided V-CUT processing is adopted, the processing method of this embodiment can also be used.

[0048] In this embodiment, the depth of the V-CUT cutting groove 310 formed by the double-sided V-CUT processing and located on one side of the flexible board is greater than the depth of the V-CUT cutting groove 310G located on one side of the rigid board.

[0049] The processing method of different double-sided depths is adopted. On the one hand, the problem of incomplete cutting depth of the flexible board during V-CUT processing caused by board bending and warping during the processing of the asymmetric circuit board is avoided. In particular, the V-CUT cutting groove 310 on one side of the flexible board is deepened, and it can effectively ensure that the polyimide material of the flexible board 210 will not cause problems such as pulling and drawing. Since the overall depth of V-CUT cutting is generally specified (generally ranging from 1 / 3 to 2 / 3 of the board thickness), the V-CUT cutting groove 310G on one side of the rigid board is lowered, but the rigid board compensation pattern 2230B needs to be cut off to prevent pulling problems when the board is subsequently disassembled.

[0050] See also Fig. 9 , Fig. 9 It is a schematic diagram of the planar structure of a rigid-flexible board formed by processing according to an embodiment of the present invention.

[0051] Step S60: The V-CUT board 30 is micro-etched to form the rigid-flex board 40 , wherein the extended area can be removed by milling or other methods.

[0052] In this embodiment, the micro-etching treatment is to stick a dry film layer to one side of the rigid board 220, expose it, and then perform the micro-etching treatment; after the micro-etching treatment is completed, the V-CUT board 30 is subjected to a strong alkali cleaning treatment; the strong alkali cleaning treatment is to use NaOH solution or KOH solution or film stripping liquid to clean the V-CUT board 30 after the micro-etching treatment.

[0053] Due to the existence of the cutting compensation pattern 2310Q, the residual copper layer pattern needs to be removed after cutting. A dry film layer is attached to one side of the rigid board 220 for protection, and the residual cutting compensation pattern 2310Q is removed by micro-etching, which can effectively and high-quality remove the residual copper layer pattern; and since the covering film layer of the flexible board 210 is processed by using a single-sided flexible copper clad laminate instead of a covering film layer, and the single-sided flexible copper clad laminate dielectric layer and the copper layer of the single-sided flexible copper clad laminate generally have a layer of glue (generally an acrylic glue layer), a strong alkali cleaning method can be selected to remove the surface glue layer to improve the quality of the covering film, and at the same time, the strong alkali cleaning can remove the dry film layer attached to one side of the rigid board 220; the glue layer is generally thin, about 3μm to 5μm, and can also be selected not to be removed; a 5% to 10% concentration solution can be used when a NaOH solution is selected, and a 3% to 5% concentration solution can be used when a KOH solution is selected.

[0054] It should be noted that due to the different designs, processing, and application scenarios of different circuit board products during the actual processing and application process, the drawings of this embodiment are only used to illustrate the implementation process of this embodiment, and do not represent the size ratio of the actual product, nor do they represent a proportionally enlarged view according to the actual situation.

[0055] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A V-CUT processing method for a rigid-flexible board with a surface flexible board layer, wherein the rigid-flexible board includes a flexible board and a rigid board in a laminated structure, wherein the flexible board is located on one side surface of the rigid board, and a V-CUT cutting line is designed on the surface of the rigid-flexible board for making a V-CUT cutting groove; It is characterized in that The processing method comprises the following steps: S10: taking a flexible board layer, pre-enlarging the size of the flexible board layer according to the design size, forming an extended area distributed on one side of the flexible board layer, and making a circuit pattern on the surface of the flexible board as a whole to form a flexible board; The boundary position between the flexible board layer and the extended area is a boundary line; S20: taking a rigid board layer, pre-enlarging the rigid board layer accordingly according to the extended area, and making a circuit pattern on the surface of the rigid board to form a rigid board; S30: stacking and pressing the flexible board and the rigid board to form a pressed board; S40: attaching a single-sided flexible copper-clad laminate to the surface of the flexible board on the laminated board, wherein the copper layer of the single-sided flexible copper-clad laminate is located on the outer surface; Taking the V-CUT cutting line as the center line, a surface compensation pattern is formed on the copper layer, wherein the width of the surface compensation pattern is greater than the maximum width of the opening of the V-CUT cutting groove; Making a solder resist pattern layer on the rigid board surface of the laminate to form a pattern board as a whole; S50: With the V-CUT cutting line as the center line, a guide groove is made for the surface compensation pattern of the extended area of ​​the graphic board, and the graphic board is V-CUT processed to form a V-CUT cutting groove to form a V-CUT board; S60: performing micro-etching on the V-CUT board to form the rigid-flex board.

2. A V-CUT processing method for a rigid-flexible board with a surface flexible board layer as claimed in claim 1, characterized in that: The surface compensation pattern is divided into a guide groove compensation pattern and a cutting compensation pattern; The guide groove compensation pattern is located within the extension area and is in a trapezoidal shape from the boundary line to the board edge.

3. A V-CUT processing method for a rigid-flexible board with a surface flexible board layer as claimed in claim 2, characterized in that: The flexible board surface circuit pattern includes a flexible board compensation pattern, The flexible board compensation pattern and the guide groove compensation pattern are distributed in corresponding layers to each other.

4. A V-CUT processing method for a rigid-flexible board with a surface flexible board layer as claimed in claim 1, characterized in that: The rigid board circuit pattern includes a rigid board compensation pattern, The rigid board compensation pattern takes the V-CUT cutting line as the center line, and has a width greater than the maximum opening width of the V-CUT cutting groove of the rigid board.

5. The V-CUT processing method of a rigid-flexible board with a surface flexible board layer as claimed in claim 1, characterized in that: The guide groove is cut from the board edge to the extension area to form a "V"-shaped groove, and the bottom of the "V"-shaped groove is connected to the V-CUT cutting line. The cutting is performed by milling with a milling cutter or punching with a die.

6. The V-CUT processing method of a rigid-flexible board with a surface flexible board layer as claimed in claim 1, characterized in that: The V-CUT processing is to cut in along the direction of the guide groove and perform V-CUT processing. The V-CUT processing is a double-sided V-CUT processing.

7. A V-CUT processing method for a rigid-flexible board with a surface flexible board layer as claimed in claim 6, characterized in that: The depth of the V-CUT cutting groove formed by the double-sided V-CUT processing and located on one side of the flexible board is greater than the depth of the V-CUT cutting groove located on one side of the rigid board.

8. The V-CUT processing method of a rigid-flexible board with a surface flexible board layer as claimed in claim 1, characterized in that: The micro-etching process is to stick a dry film layer on one side of the rigid board, expose it to light, and then perform the micro-etching process.

9. A V-CUT processing method for a rigid-flexible board with a surface flexible board layer as claimed in claim 1 or 8, characterized in that: After the micro-etching process is completed, the V-CUT board is cleaned with a strong alkali.

10. A V-CUT processing method for a rigid-flexible board with a surface flexible board layer as claimed in claim 9, characterized in that: The strong alkali cleaning treatment is to clean the V-CUT board after the micro-etching treatment using a NaOH solution or a KOH solution or a film stripping solution.

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