Printed circuit board and manufacturing method thereof

Abstract

The invention discloses a printed circuit board and a manufacturing method thereof. The manufacturing method of the printed circuit board comprises the steps that adhesive tapes are attached to the two faces of a base body of the printed circuit board; removing the adhesive tape at the slotted hole position of the base body; the base body attached with the adhesive tape is soaked in anti-etching printing ink; removing other adhesive tapes; and etching a circuit on the surface of the substrate. An adhesive tape is attached to a substrate of the printed circuit board, the adhesive tape at the position of the slot is removed, when the substrate is soaked in the anti-etching ink, the anti-etching ink is attached to the position of the slot of the substrate, and the anti-etching ink does not exist on the plate surface of the substrate due to the attached adhesive tape; the plate surface of the substrate can be etched by adopting a conventional dry film, so that the precision of the circuit is ensured, the position of the slot is prevented from being influenced by etching, and the phenomenon that the slot is free of copper is prevented.

Description

Technical Field

[0001] The present application relates to the technical field of circuit board manufacturing, and in particular to a printed circuit board and a manufacturing method thereof. Background Art

[0002] Slots are designed on printed circuit board products to facilitate product installation. When the slot size is large, in order to avoid the slot being without copper after the product is etched, the traditional method is to use a thick dry film with a thickness of more than 50μm to seal the hole. However, the resolution of the thick dry film is poor, which is not conducive to the production of precision circuits.

[0003] To solve this problem, some manufacturers currently use the method of laminating dry films twice, with two layers of dry film at the slot position and only one layer of dry film at the non-slot position. However, this process has the risk of the dry films not being firmly laminated twice, and precision circuits cannot be made at the overlapping positions of the dry films at the slot edges. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a method for manufacturing a printed circuit board, which ensures the presence of copper in the slots by attaching an adhesive tape combined with soaking in an anti-etching ink, and does not affect the etching of fine circuits.

[0005] The present application also provides a printed circuit board manufactured by the above-mentioned printed circuit board manufacturing method.

[0006] According to the printed circuit board manufacturing method of the first aspect embodiment of the present application, the printed circuit board manufacturing method includes:

[0007] Attaching tape to both sides of the substrate of the printed circuit board;

[0008] Removing the tape from the slots of the substrate;

[0009] soaking the substrate with the adhesive tape attached thereto in anti-etching ink;

[0010] Remove the remaining tape;

[0011] Circuits are etched on the surface of the substrate.

[0012] According to the printed circuit board manufacturing method of the embodiment of the present application, at least the following beneficial effects are achieved: the substrate of the printed circuit board is attached with tape, and the tape at the slot position is removed. When the substrate is immersed in anti-etching ink, the slot position of the substrate is attached with anti-etching ink, while the board surface of the substrate does not have anti-etching ink due to the attached tape; the board surface of the substrate can be etched with conventional dry film to ensure the precision of the circuit, avoid the slot position being affected by etching, and prevent the occurrence of copper-free slots.

[0013] According to some embodiments of the present application, after the adhesive tape is attached to both sides of the substrate of the printed circuit board, the method includes:

[0014] The adhesive tape is rolled by a roller so that there is no gap between the adhesive tape and the plate surface of the substrate.

[0015] According to some embodiments of the present application, removing the tape at the slot position of the substrate includes:

[0016] Cutting off the tape at the slot position of the substrate;

[0017] Use a roller to apply and remove the cut tape.

[0018] According to some embodiments of the present application, the step of cutting off the tape at the slot position of the substrate includes:

[0019] The cut-off size of the tape is 0.05mm to 0.1mm more on one side based on the size of the slot.

[0020] According to some embodiments of the present application, after the tape at the slot position of the substrate is cut off, the method includes:

[0021] Cutting off the tape at the location of the positioning hole of the substrate;

[0022] The tape is cut away from the edge of the substrate to form a technical edge.

[0023] According to some embodiments of the present application, the step of immersing the substrate with the tape attached thereto in an anti-etching ink comprises:

[0024] Etch-resistant inks include thermosetting epoxy inks.

[0025] According to some embodiments of the present application, after immersing the substrate with the tape attached thereto in the anti-etching ink, the method comprises:

[0026] Drying of anti-etching ink;

[0027] The substrate is polished to remove the anti-etching ink adhered to the plate surface of the substrate.

[0028] According to some embodiments of the present application, after removing the remaining tapes, the method includes:

[0029] A dry film is attached to the entire substrate.

[0030] According to some embodiments of the present application, after etching the circuit on the surface of the substrate, the method includes:

[0031] The substrate is stripped with a strong alkaline solution, and the anti-etching ink on the substrate is removed.

[0032] The printed circuit board according to the embodiment of the second aspect of the present application is manufactured by using the above-mentioned printed circuit board manufacturing method.

[0033] The printed circuit board according to the embodiment of the present application has at least the following beneficial effects: it is prepared by the printed circuit board manufacturing method of the embodiment of the first aspect of the present application, the substrate is attached with tape, and the tape at the slot position is removed, when the substrate is immersed in anti-etching ink, the slot position of the substrate is attached with anti-etching ink, and the board surface of the substrate does not have anti-etching ink due to the attached tape; the board surface of the substrate can be etched with conventional dry film to ensure the precision of the circuit, and avoid the slot position being affected by etching, thereby preventing the occurrence of copper-free slots.

[0034] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present application is further illustrated below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments embodied in the following drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0036] Figure 1 is a top view of a substrate in a method for manufacturing a printed circuit board according to an embodiment of the present application;

[0037] Figure 2 It is a top view of a printed circuit board after the first dry film is attached in a method for manufacturing a printed circuit board in the related art;

[0038] Figure 3 It is a top view of a printed circuit board after the second dry film is attached in a method for manufacturing a printed circuit board in the related art;

[0039] Figure 4 It is a top view and a front view of the printed circuit board after the adhesive tape is attached in the printed circuit board manufacturing method of the embodiment of the present application;

[0040] Figure 5 It is a top view and a front view of the printed circuit board after the tape is removed from the slot hole in the printed circuit board manufacturing method of the embodiment of the present application;

[0041] Figure 6 It is a top view and a front view of a printed circuit board after being immersed in an anti-etching ink in the method for manufacturing a printed circuit board according to an embodiment of the present application;

[0042] Figure 7 The printed circuit board after etching in the printed circuit board manufacturing method of the embodiment of the present application;

[0043] Figure 8 is a flow chart of a method for manufacturing a printed circuit board according to an embodiment of the present application;

[0044] Fig. 9 is a flow chart of a method for manufacturing a printed circuit board according to another embodiment of the present application;

[0045] Fig.10 is a flow chart of a method for manufacturing a printed circuit board according to another embodiment of the present application;

[0046] Fig.11 is a flow chart of a method for manufacturing a printed circuit board according to another embodiment of the present application;

[0047] Fig.12 is a flow chart of a method for manufacturing a printed circuit board according to another embodiment of the present application;

[0048] Fig.13 is a flow chart of a method for manufacturing a printed circuit board according to another embodiment of the present application;

[0049] Fig.14 is a flow chart of a method for manufacturing a printed circuit board according to another embodiment of the present application;

[0050] Fig.15 is a flow chart of a method for manufacturing a printed circuit board according to another embodiment of the present application;

[0051] Fig.16 It is a flow chart of a method for manufacturing a printed circuit board according to another embodiment of the present application.

[0052] Reference numerals:

[0053] Base 100; slot 101; positioning hole 102;

[0054] Dry film 200; tape 301; anti-etching ink 302; circuit 303. DETAILED DESCRIPTION

[0055] The embodiments of the present application are described in detail below in conjunction with the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0056] In the description of the present application, it should be understood that the terms "center", "middle", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0057] In the description of this application, "several" means more than one, "more" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0058] In the description of this application, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0059] In the description of the present application, if there is a description with reference to the terms "one embodiment", "some embodiments", "an embodiment", "some examples", "some embodiments", "illustrative embodiment", "example", "specific example", "some examples", etc., it means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0060] An embodiment of the present application provides a method for manufacturing a printed circuit board. In the method, a printed circuit board substrate 100 is attached with a tape 301 and immersed in an anti-etching ink 302, so as to facilitate the production of a precision circuit 303 on the surface of the printed circuit board and avoid the situation where there is no copper in the slot 101 during the etching process.

[0061] In the manufacturing process of large-size slotted printed circuit boards, when the copper plating thickness is required to be above 80μm, the etching time will be prolonged in order to remove the copper at non-circuit positions. Long-term etching will cause the printed circuit board to be subjected to long-term chemical spraying, and the dry film at the slot 101 position of the printed circuit board will be easily penetrated by the spraying chemical, and the copper on the side wall of the slot 101 will be easily etched away, causing the slot to be broken.

[0062] In order to avoid the slot hole from breaking, a thick dry film of more than 50μm is often used for sealing. However, the bottom part of the thick dry film close to the copper sheet cannot be cured by ultraviolet light. When etching with liquid medicine, this part will be etched by the liquid medicine, and the etched circuit is very rough, which cannot realize the production of precise circuits. That is, the resolution of the thick dry film is poor, and precise circuits cannot be produced.

[0063] In addition, the related art adopts a process method of laminating two dry films, such as Figure 1 and Figure 2 As shown, the dry film 200 is applied to the slot 101 of the substrate 100 of the printed circuit board for the first time; Figure 1 and Figure 3 As shown, the second time, the dry film 200 is applied to the entire substrate 100 of the printed circuit board. Then, there are two layers of dry film 200 at the slot hole 101 position, and only one layer of dry film 200 at the non-slot hole position. This process solution has the risk of the dry film 200 being not firmly applied twice, that is, the film is easily thrown off, and the overlapped position of the dry film 200 at the edge of the slot hole 101 also has poor resolution, and it is impossible to make a precise circuit.

[0064] Various embodiments of the printed circuit board manufacturing method of the present application are presented below.

[0065] like Figure 8 As shown, Figure 8 It is a flowchart of a printed circuit board manufacturing method provided by an embodiment of the present application. The printed circuit board manufacturing method includes but is not limited to step S110, step S120, step S130, step S140 and step S150.

[0066] Step S110 , attaching adhesive tape 301 to both sides of the substrate 100 of the printed circuit board.

[0067] like Figure 4 As shown, in some examples, the entire surface of the substrate 100 of the printed circuit board is affixed with tape 301. It can be understood that the tape 301 can isolate the anti-etching ink 302, prevent the anti-etching ink 302 from adhering to the surface of the substrate 100 in subsequent processes, and prevent the anti-etching ink 302 from affecting the etching of the precision circuit 303.

[0068] Specifically, the board surfaces at two opposite ends of the substrate 100 are both adhered with adhesive tapes 301 , and the substrate 100 is located between two layers of adhesive tapes 301 .

[0069] Furthermore, there are several relatively large slots 101 on the surface of the substrate 100 . When the adhesive tape 301 is attached to the entire substrate 100 , the adhesive tape 301 will block the slots 101 , and the adhesive tape 301 at the slots 101 needs to be removed in a subsequent process.

[0070] Step S120 , removing the tape 301 at the position of the slot hole 101 of the substrate 100 .

[0071] like Figure 5 As shown, in some examples, the anti-etching ink 302 needs to be attached to the slot 101 of the substrate 100 to prevent the copper at the slot 101 from being affected by the etching solution. Therefore, the slot 101 does not need to be attached with the tape 301 to facilitate the attachment of the anti-etching ink 302.

[0072] Step S130 , immersing the substrate 100 attached with the tape 301 in the anti-etching ink 302 .

[0073] In some examples, since the tape 301 is attached to the board surface of the substrate 100, and there is no tape 301 at the slot 101 position of the substrate 100, the anti-etching ink 302 will adhere to the slot 101 position, so that the slot 101 position has the ability to resist etching and protect the copper at the slot 101 position. Other positions on the board surface of the substrate 100 are isolated from the anti-etching ink 302, which facilitates etching of the precision circuit 303 on the board surface of the substrate 100.

[0074] Specifically, the substrate 100 of the printed circuit board is immersed in the anti-etching ink 302 for 3 to 5 minutes to ensure the adhesion process of the anti-etching ink 302 .

[0075] Step S140, removing the remaining tape 301.

[0076] like Figure 6 As shown, in some examples, the tape 301 attached to the surface of the substrate 100 may hinder the etching process. Therefore, before the etching process, the tape 301 needs to be removed to expose the surface of the substrate 100.

[0077] Step S150 , etching a circuit 303 on the surface of the substrate 100 .

[0078] In addition, refer to Fig. 9 Step S110: After the adhesive tape 301 is attached to both sides of the substrate 100 of the printed circuit board, the following steps may be included but are not limited to:

[0079] Step S210 , using a roller to roll the adhesive tape 301 so that there is no gap between the adhesive tape 301 and the board surface of the substrate 100 .

[0080] In some examples, in order to ensure that the tape 301 is evenly attached to the board surface of the substrate 100, after the tape 301 is attached to the board surface of the substrate 100, it is necessary to use a roller to roll the tape 301 to ensure that there is no gap between the tape 301 and the board surface, so as to prevent the anti-etching ink 302 from entering between the tape 301 and the board surface along the gap.

[0081] It is understandable that both end surfaces of the base 100 need to be rolled using rollers.

[0082] In addition, refer to Fig.10 Step S120: removing the tape 301 at the slot hole 101 of the substrate 100, which may include but is not limited to the following steps:

[0083] Step S310 , cutting off the adhesive tape 301 at the location of the slot hole 101 of the substrate 100 .

[0084] In some examples, a UV laser machine is used to cut the tape 301 at the slot 101 to ensure the accuracy of the tape 301 cutting process. The UV laser machine is used to cut the tape 301, and a subsequent process is required to remove the cut tape 301 from the board surface of the substrate 100.

[0085] Step S320 , using a roller to stick and remove the cut tape 301 .

[0086] In some examples, the surface of the roller is sticky, and the roller can stick to the cut tape 301 on the surface of the substrate 100 and remove the tape 301 at the slot hole 101 to expose the slot hole 101 on the surface of the substrate 100 .

[0087] In addition, refer to Fig.11 Step S310: removing the tape 301 at the slot 101 of the substrate 100, which may include but is not limited to the following steps:

[0088] Step S410 , the cutting size of the tape 301 is increased by 0.05 mm to 0.1 mm on one side based on the size of the slot 101 .

[0089] In some examples, the UV laser machine has a certain cutting error, so the cut size of the tape 301 is 0.05mm to 0.1mm larger than the size of the slot 101. Specifically, the cut size of the tape 301 needs to be set according to the cutting error of the UV laser machine.

[0090] In addition, refer to Fig.12 Step S310: After the tape 301 at the slot 101 of the base 100 is cut off, the following steps may be included but not limited to:

[0091] Step S510 , cutting off the adhesive tape 301 at the location of the positioning hole 102 of the substrate 100 .

[0092] In some examples, in addition to the slot hole 101, there is also a positioning hole 102 on the substrate 100. The substrate 100 is positioned on the relevant equipment or tooling through the positioning hole 102, which facilitates the subsequent soaking of the substrate 100 in the anti-etching ink 302 and the etching process. Therefore, the tape 301 needs to be cut off at the location of the positioning hole 102 of the substrate 100 to expose the positioning hole 102.

[0093] Step S520 , cutting off the tape 301 at the edge of the substrate 100 to form a process edge.

[0094] In some examples, the size of the tape 301 needs to adapt to the size of the substrate 100. When the size of the tape 301 is larger than the size of the substrate 100, the tape 301 will extend beyond the edge of the substrate 100. The tape 301 extending beyond the edge of the substrate 100 will also adhere to the ink when soaking the anti-etching ink 302, and will take the ink away from the corresponding container during the process of removing the anti-etching ink 302 from the substrate 100, thereby polluting the surrounding environment. Cutting off the tape 301 at the edge of the substrate 100 can avoid the above problems.

[0095] Furthermore, the size of the tape 301 can be slightly smaller than the board size of the substrate 100, so as to form a process edge at the edge of the substrate 100. It is understandable that the edge of the substrate 100 will also be stained with the anti-etching ink 302, but the position of the process edge does not need to etch the line 303, and has no effect on the performance of the product.

[0096] In addition, refer to Fig.13 Step S130: soaking the substrate 100 with the tape 301 attached thereto in the anti-etching ink 302, which may include but is not limited to the following steps:

[0097] In step S610 , the anti-etching ink 302 includes thermosetting epoxy resin ink.

[0098] In some examples, the thermosetting epoxy resin ink is also called anti-plating ink. The thermosetting epoxy resin ink has strong acid resistance, but will dissolve in strong alkali, so the anti-etching ink 302 can isolate the etching solution.

[0099] When the substrate 100 with the tape 301 attached thereto is soaked in the anti-etching ink 302, the anti-etching ink 302 adheres to the slot 101 of the substrate 100 and covers the outer side of the copper at the slot 101. During the etching process, the anti-etching ink 302 can isolate the etching solution and the copper at the slot 101 to prevent the slot 101 from being broken. At the same time, the board surface of the substrate 100 will not adhere to the anti-etching ink 302 due to the isolation effect of the tape 301, and etching can be performed normally.

[0100] In addition, refer to Fig.14Step S130: After the substrate 100 with the adhesive tape 301 attached thereto is immersed in the anti-etching ink 302, the following steps may be included but are not limited to:

[0101] Step S710 , drying the anti-etching ink 302 .

[0102] In some examples, after the anti-etching ink 302 is attached to the slot 101 of the substrate 100 , the anti-etching ink 302 needs to be dried to ensure that the anti-etching ink 302 is solidified at the current position.

[0103] Step S720 , grinding the substrate 100 to remove the anti-etching ink 302 adhered to the surface of the substrate 100 .

[0104] In some examples, the anti-etching ink 302 just attached to the substrate 100 still has a certain fluidity, and the anti-etching ink 302 may adhere to the surface of the substrate 100. In this case, the substrate 100 needs to be polished to remove the anti-etching ink 302 on the surface of the substrate 100, laying a foundation for the subsequent etching process.

[0105] In addition, refer to Fig.15 Step S140: After removing the remaining tape 301, the following steps may be included but not limited to:

[0106] Step S810 , attaching the dry film 200 to the entire substrate 100 .

[0107] In some examples, since the anti-etching ink 302 has been cured at the slot 101 of the substrate 100, there is no need to attach the dry film 200 to the slot 101, and a common thin dry film 200 can be attached to the entire surface of the substrate 100. The thin dry film 200 has a high resolution and ensures the production of the precision circuit 303.

[0108] It is understandable that the thin dry film 200 is easily damaged after being attached to the large-sized slot 101. Even if the thin dry film 200 at the slot 101 is penetrated by the etching solution, the copper at this position will not be etched away because the side wall of the slot 101 is protected by the anti-etching ink 302.

[0109] In addition, refer to Fig.16 Step S150: After etching the circuit 303 on the surface of the substrate 100, the following steps may be included but not limited to:

[0110] Step S910 , using a strong alkaline solution to strip the substrate 100 and remove the anti-etching ink 302 on the substrate 100 .

[0111] In some examples, after the etching process of the circuit 303 is completed, the cured anti-etching ink 302 on the substrate 100 needs to be removed, and the anti-etching ink 302 is soluble in a strong alkali, and the anti-etching ink 302 can be removed by stripping with a strong alkali solution, ensuring that there is no ink residue at the slot 101 of the substrate 100. Specifically, the stripping solution can be a 3% to 5% sodium hydroxide solution.

[0112] An embodiment of the present application provides a printed circuit board, which is manufactured using the above-mentioned printed circuit board manufacturing method.

[0113] In the actual implementation process, first, the tape 301 is attached to the surface of the substrate 100 of the printed circuit board, and the tape 301 at the position of the slot 101 is removed. Secondly, the substrate 100 with the tape 301 attached is immersed in the anti-etching ink 302, and the anti-etching ink 302 will be solidified at the position of the slot 101 of the substrate 100. Thirdly, the tape 301 is removed, and the conventional circuit etching process is carried out by attaching the thin dry film 200, ensuring the precision of the circuit 303 while avoiding the occurrence of the slot 101 hole phenomenon. Finally, the film is stripped with a strong alkaline solution to complete the manufacturing process of the printed circuit board.

[0114] The above is a detailed description of the implementation methods of the present application in conjunction with the accompanying drawings, but the present application is not limited to the above implementation methods. Various changes can be made within the knowledge of ordinary technicians in the technical field without departing from the purpose of the present application. In addition, the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

Claims

1. A method for manufacturing a printed circuit board, characterized in that: include: Attaching tape to both sides of the substrate of the printed circuit board; Removing the tape from the slots of the substrate; soaking the substrate with the adhesive tape attached thereto in anti-etching ink; Remove the remaining tape; Circuits are etched on the surface of the substrate.

2. The method for manufacturing a printed circuit board according to claim 1, characterized in that: After the adhesive tape is attached to both sides of the substrate of the printed circuit board, the method comprises: The adhesive tape is rolled by a roller so that there is no gap between the adhesive tape and the plate surface of the substrate.

3. The method for manufacturing a printed circuit board according to claim 1, characterized in that: Removing the tape from the slot position of the substrate, comprising: Cutting off the tape at the slot position of the substrate; Use a roller to apply and remove the cut tape.

4. The method for manufacturing a printed circuit board according to claim 3, characterized in that: The adhesive tape for cutting out the slot position of the substrate comprises: The cut-off size of the tape is 0.05mm to 0.1mm more on one side based on the size of the slot.

5. The method for manufacturing a printed circuit board according to claim 3, characterized in that: After the tape at the slot position of the substrate is cut off, the method comprises: Cutting off the tape at the location of the positioning hole of the substrate; The tape is cut away from the edge of the substrate to form a technical edge.

6. The method for manufacturing a printed circuit board according to claim 1, characterized in that: The step of immersing the substrate with the adhesive tape attached thereto in an anti-etching ink comprises: Etch-resistant inks include thermosetting epoxy inks.

7. The method for manufacturing a printed circuit board according to claim 1, characterized in that: After the substrate with the adhesive tape attached thereto is immersed in the anti-etching ink, the method comprises: Drying of anti-etching ink; The substrate is polished to remove the anti-etching ink adhered to the plate surface of the substrate.

8. The method for manufacturing a printed circuit board according to claim 1, characterized in that: After removing the remaining tape, the steps include: A dry film is attached to the entire substrate.

9. The method for manufacturing a printed circuit board according to claim 1, characterized in that: After etching the circuit on the surface of the substrate, the method comprises: The substrate is stripped with a strong alkaline solution, and the anti-etching ink on the substrate is removed.

10. A printed circuit board, characterized in that: The printed circuit board is manufactured by the method for manufacturing the printed circuit board as claimed in any one of claims 1 to 9.

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