Grounding components and shielded printed circuit boards

Abstract

A grounding component is provided, which can prevent the interlayer tightness between the conductive layer and the adhesive layer of the grounding component from being destroyed due to heating when manufacturing a shielded printed circuit board or when mounting electronic components on the shielded printed circuit board. The grounding component of the present invention includes a conductive layer and an adhesive layer laminated on the conductive layer, and the grounding component is characterized in that the adhesive layer has a binder component and hard particles, and the thickness of the adhesive layer is 5 to 30 μm.

Description

Technical Field

[0001] The invention relates to a grounding component and a shielded printed circuit board. Background Art

[0002] Printed circuit boards are often used to assemble circuits into mechanisms in electronic devices such as mobile phones, video cameras, and notebook personal computers. In addition, printed circuit boards are also used to connect movable parts such as print heads with control parts. Electromagnetic wave shielding measures are essential in the above electronic devices, and shielded printed circuit boards that implement electromagnetic wave shielding measures are also used in printed circuit boards used in devices.

[0003] As a measure for electromagnetic wave shielding, a method of covering a printed wiring board with a conductive shielding layer is known.

[0004] In addition, there is also known a method of dealing with noise by electrically connecting a ground circuit of a printed wiring board and an external ground via a shield layer.

[0005] Patent Document 1 discloses a shielded printed wiring board further including an external grounding member for ensuring electrical connection between a ground circuit of the printed circuit and an external ground.

[0006] That is, patent document 1 discloses a shielded printed circuit board, which includes a printed circuit board and an electromagnetic wave shielding layer covering at least a portion of the circuits of the printed circuit board, and the shielded printed circuit board also includes an external grounding component, the external grounding component is electrically connected to the grounding circuit of the printed circuit board and to an external grounding component, wherein the electromagnetic wave shielding layer is electrically connected to the grounding circuit of the printed circuit board and the external grounding component, a portion of the external grounding component exists between the printed circuit board and the electromagnetic wave shielding layer, and another portion of the external grounding component has one side placed on the printed circuit board and the other side exposed.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent document 1: Japanese Patent Laid-Open No. 2016-122687. Summary of the invention

[0010] Technical problem to be solved by the invention

[0011] The external grounding member (grounding member) described in Patent Document 1 is composed of a metal foil (conductive layer) and an adhesive layer provided on one surface of the metal foil.

[0012] Furthermore, the printed wiring board described in Patent Document 1 has a structure in which a printed pattern on a base film is covered with an insulating film (cover film).

[0013] When manufacturing a shielded printed wiring board using a grounding member as described above, the grounding member is first placed on the printed wiring board so that the adhesive layer of the grounding member contacts the printed wiring board. Thereafter, the grounding member is bonded and fixed to the printed wiring board by heat pressing.

[0014] Furthermore, electronic components are mounted on the shielded printed circuit board including the grounding member, and solder is used when mounting the electronic components. When mounting the electronic components by solder reflow, the shielded printed circuit board is heated.

[0015] When manufacturing a shielded printed circuit board as described above, or when mounting electronic components on the shielded printed circuit board, if the shielded printed circuit board is heated, gas may be generated from the adhesive layer of the grounding member, the cover film of the printed circuit board, etc. In addition, when the base film of the printed circuit board is formed of a highly hygroscopic resin such as polyimide, water vapor may be generated from the base film due to heating. The above-mentioned volatile components generated from the adhesive layer, cover film, and base film of the grounding member cannot pass through the conductive layer of the grounding member, and therefore accumulate between the conductive layer and the adhesive layer.

[0016] Therefore, if further rapid heating is performed, the volatile components accumulated between the conductive layer and the adhesive layer of the ground member expand, thereby destroying the interlayer adhesion between the conductive layer and the adhesive layer of the ground member.

[0017] In view of the above problems, the present invention aims to provide a grounding member that can prevent the interlayer adhesion between the conductive layer and the adhesive layer of the grounding member from being destroyed due to heating when manufacturing a shielded printed wiring board and when electronic components are mounted on the shielded printed wiring board.

[0018] Technical means to solve technical problems

[0019] The grounding component of the present invention comprises a conductive layer and an adhesive layer laminated on the conductive layer. The grounding component is characterized in that the adhesive layer contains a binder component and hard particles, and the thickness of the adhesive layer is 5 to 30 μm.

[0020] The grounding component of the present invention is used for manufacturing a shielded printed wiring board.

[0021] That is, when manufacturing a shielded printed wiring board, the grounding member of the present invention is disposed on the printed wiring board so that the adhesive layer contacts the cover film of the printed wiring board.

[0022] After that, the grounding member is bonded and fixed to the printed wiring board by heat pressing.

[0023] The hard particles contained in the adhesive layer of the ground member of the present invention press the conductive layer of the ground member during the hot pressing, thereby forming holes and depressions in the conductive layer through which volatile components can pass.

[0024] Therefore, even if volatile components are generated due to heating during the process of manufacturing the shielded printed wiring board, the volatile components can pass through the conductive layer.

[0025] Furthermore, when electronic components are mounted on a shielded printed wiring board using the grounding member of the present invention, even if the shielded printed wiring board is heated in a solder reflow process and volatile components are generated, the volatile components can pass through the conductive layer.

[0026] That is, it is possible to prevent volatile components from being accumulated between the conductive layer and the adhesive layer of the ground member.

[0027] This can prevent the interlayer adhesion between the conductive layer and the adhesive layer of the grounding member from being destroyed due to heat when the shielded printed wiring board is manufactured or when the electronic components are mounted on the shielded printed wiring board.

[0028] The thickness of the adhesive layer of the grounding member of the present invention is 5 to 30 μm.

[0029] When the thickness of the adhesive layer is less than 5 μm, the bonding strength is insufficient.

[0030] When the thickness of the adhesive layer exceeds 30 μm, the pressure of the hard particles pressing the conductive layer during hot pressing is dispersed, and holes and depressions through which the volatile components can pass cannot be formed in the conductive layer.

[0031] In the grounding member of the present invention, it is preferred that the Mohs hardness of the hard particles is 1.5 times or more the Mohs hardness of the conductive layer.

[0032] If the Mohs hardness of the hard particles is 1.5 times or more the Mohs hardness of the conductive layer, the hard particles are easily embedded in the conductive layer during hot pressing.

[0033] This makes it easy to form holes and depressions in the conductive layer through which volatile components can pass.

[0034] In the grounding member of the present invention, it is preferred that the hard particles have a Mohs hardness of 4-7.

[0035] When the Mohs hardness of the hard particles is 4 to 7, the particles will not break during hot pressing, and holes and depressions through which the volatile components can pass can be easily formed in the conductive layer.

[0036] In the grounding member of the present invention, it is preferred that the hard particles have an average particle size of 2.5 to 25 μm.

[0037] When the average particle size of the hard particles is within the above range, holes and depressions through which the volatile component can pass can be appropriately formed in the conductive layer during hot pressing.

[0038] If the average particle size of the hard particles is less than 2.5 μm, it is difficult to form sufficiently large pores or depressions in the conductive layer during hot pressing, and volatile components are unlikely to pass through the conductive layer.

[0039] When the average particle size of the hard particles exceeds 25 μm, the holes and depressions formed in the conductive layer during hot pressing become large, and the strength of the conductive layer tends to decrease.

[0040] In the grounding member of the present invention, it is preferred that the hard particles are made of silicon dioxide.

[0041] The Mohs hardness of silicon dioxide is high enough to suitably function as hard particles.

[0042] In the ground member of the present invention, it is preferable that the conductive layer is formed of at least one selected from the group consisting of copper, silver, gold, and nickel.

[0043] In the shielded printed wiring board using the grounding member of the present invention, the conductive layer of the grounding member is electrically connected to the grounding circuit of the printed wiring board. In addition, in the shielded printed wiring board using the grounding member of the present invention, the conductive layer is connected to the external ground.

[0044] When the conductive layer of the grounding member is formed of at least one selected from the group consisting of copper, silver, gold and nickel, the above-mentioned materials have excellent conductivity, so the resistance value between the grounding circuit and the external ground can be reduced.

[0045] In the grounding member of the present invention, it is preferred that the adhesive layer further include conductive particles.

[0046] In this case, the adhesive layer functions as a conductive adhesive layer.

[0047] In the grounding member of the present invention, it is preferred that the average particle size of the hard particles is smaller than the average particle size of the conductive particles.

[0048] When the average particle diameter of the hard particles is larger than the average particle diameter of the conductive particles, the hard particles are easily exposed from the adhesive layer of the grounding member, and thus the adhesive layer is easily lost in adhesion.

[0049] In the ground member of the present invention, it is preferred that the Mohs hardness of the hard particles is higher than the Mohs hardness of the conductive particles.

[0050] When the Mohs hardness of the hard particles is higher than that of the conductive particles, even if the object to be bonded of the ground member of the present invention is soft, holes and depressions through which volatile components can pass are easily formed in the conductive layer.

[0051] In the grounding member of the present invention, it is preferable that the thickness of the binder component of the adhesive layer is smaller than the average particle diameter of the conductive particles.

[0052] The grounding member of the present invention may be disposed on an electromagnetic wave shielding film including a protective layer and a shielding layer laminated on the protective layer.

[0053] At this time, the grounding member is arranged so that the adhesive layer of the grounding member is in contact with the protective layer of the electromagnetic wave shielding film, and the conductive particles of the grounding member penetrate the protective layer of the electromagnetic wave shielding film.

[0054] In this case, when the thickness of the binder component of the adhesive layer is smaller than the average particle size of the conductive particles, the conductive particles can surely penetrate the protective layer of the electromagnetic shielding film, so that the conductive particles are in contact with the shielding layer of the electromagnetic shielding film.

[0055] The grounding member of the present invention may be disposed on an electromagnetic wave shielding film including a protective layer and a shielding layer laminated on the protective layer, so that the adhesive layer is in contact with the protective layer and the conductive particles penetrate the protective layer.

[0056] The conductive layer of the grounding member of the present invention is connected to the external ground, and the shielding layer of the electromagnetic wave shielding film is electrically connected to the grounding circuit of the printed wiring board.

[0057] The conductive particles of the ground member of the present invention penetrate the protective layer of the electromagnetic wave shielding film and come into contact with the shielding layer of the electromagnetic wave shielding film.

[0058] Thus, by using the ground member of the present invention, the ground circuit of the printed wiring board using the electromagnetic wave shielding film and the external ground can be electrically connected.

[0059] The grounding component of the present invention can be arranged on a shielded printed circuit board, wherein the shielded printed circuit board comprises: a printed circuit board, which is composed of a base film, a printed circuit including a grounding circuit arranged on the above-mentioned base film, and a covering film covering the above-mentioned printed circuit; a shielding layer, which is arranged on the above-mentioned covering film and is electrically connected to the above-mentioned grounding circuit; a protective layer, which is provided on the surface of the above-mentioned shielding layer on the opposite side of the above-mentioned printed circuit side; and the above-mentioned grounding component is arranged so that the above-mentioned adhesive layer is in contact with the above-mentioned protective layer and the above-mentioned conductive particles penetrate the above-mentioned protective layer.

[0060] The conductive layer of the ground member of the present invention is electrically connected to the external ground.

[0061] The conductive particles of the grounding member penetrate the protective layer of the shielding printed wiring board and come into contact with the shielding layer.

[0062] In this way, the ground circuit of the shielded printed wiring board and the external ground can be electrically connected by using the ground member of the present invention.

[0063] In the grounding member of the present invention, the adhesive layer may have insulating properties, and a conductive bump may be formed on the conductive layer on the adhesive layer side.

[0064] When the ground member has a conductive bump, the conductive layer and the object to be joined can be electrically connected via the conductive bump.

[0065] The shielded printed circuit board of the present invention includes: a printed circuit board, which is composed of a base film, a printed circuit including a grounding circuit arranged on the above-mentioned base film, and a covering film covering the above-mentioned printed circuit; a shielding layer, which is arranged on the above-mentioned covering film and electrically connected to the above-mentioned grounding circuit; the above-mentioned shielded printed circuit board is characterized in that it also includes the above-mentioned grounding component of the present invention, wherein the above-mentioned grounding component is arranged so that the adhesive layer of the above-mentioned grounding component is in contact with the above-mentioned covering film, and the conductive layer of the above-mentioned grounding component is electrically connected to the above-mentioned shielding layer.

[0066] In addition, another shielded printed circuit board of the present invention includes: a printed circuit board, which is composed of a base film, a printed circuit including a grounding circuit arranged on the above-mentioned base film, and a covering film covering the above-mentioned printed circuit; an electromagnetic wave shielding film, which is arranged on the above-mentioned covering film, and is composed of a conductive adhesive layer, a shielding layer laminated on the conductive adhesive layer, and the above-mentioned conductive adhesive layer is electrically connected to the above-mentioned grounding circuit; the above-mentioned shielded printed circuit board is characterized in that: it also includes the above-mentioned grounding component of the present invention, wherein the above-mentioned grounding component is arranged so that the adhesive layer of the above-mentioned grounding component is in contact with the above-mentioned covering film, and the conductive layer of the above-mentioned grounding component is electrically connected to the conductive adhesive layer of the above-mentioned electromagnetic wave shielding film.

[0067] Another shielded printed circuit board of the present invention includes: a printed circuit board, which is composed of a base film, a printed circuit including a grounding circuit arranged on the above-mentioned base film, and a covering film covering the above-mentioned printed circuit; a shielding layer, which is arranged on the above-mentioned covering film and is electrically connected to the above-mentioned grounding circuit; a protective layer, which is arranged on the surface of the above-mentioned shielding layer opposite to the above-mentioned printed circuit side; the above-mentioned shielded printed circuit board is characterized in that: it also includes the above-mentioned grounding component of the present invention, wherein the above-mentioned grounding component is arranged so that the adhesive layer of the above-mentioned grounding component is in contact with the above-mentioned protective layer, and the conductive particles of the above-mentioned grounding component penetrate the above-mentioned protective layer and are electrically connected to the conductive layer of the above-mentioned grounding component and the above-mentioned shielding layer.

[0068] In addition, another shielded printed circuit board of the present invention includes: a printed circuit board, which is composed of a base film, a printed circuit including a grounding circuit arranged on the above-mentioned base film, and a covering film covering the above-mentioned printed circuit; a shielding layer, which is arranged on the above-mentioned covering film and is electrically connected to the above-mentioned grounding circuit; a protective layer, which is arranged on the surface of the above-mentioned shielding layer opposite to the above-mentioned printed circuit side; the above-mentioned shielded printed circuit board is characterized in that: it also includes the above-mentioned grounding component of the present invention, wherein the above-mentioned grounding component is arranged so that the adhesive layer of the above-mentioned grounding component is in contact with the above-mentioned protective layer, and the conductive bump of the above-mentioned grounding component penetrates the above-mentioned protective layer and is electrically connected to the conductive layer of the above-mentioned grounding component and the above-mentioned shielding layer.

[0069] The shielded printed wiring board of the present invention includes the grounding member of the present invention.

[0070] Therefore, it is possible to prevent the interlayer adhesion between the conductive layer and the adhesive layer of the ground member from being destroyed due to heat when manufacturing the shielded printed wiring board or mounting the electronic components on the shielded printed wiring board.

[0071] Effects of the Invention

[0072] The grounding member of the present invention is used when manufacturing a shielded printed wiring board.

[0073] During hot pressing when manufacturing a shielded printed wiring board, the hard particles contained in the adhesive layer of the grounding member of the present invention press the conductive layer of the grounding member, forming holes and depressions in the conductive layer through which volatile components can pass.

[0074] Therefore, even if volatile components are generated by heating during the process of manufacturing the shielded printed wiring board, the volatile components can pass through the conductive layer, that is, the volatile components can be prevented from accumulating between the conductive layer and the adhesive layer of the grounding member.

[0075] This can prevent the interlayer adhesion between the conductive layer and the adhesive layer of the grounding member from being destroyed due to heat when the shielded printed wiring board is manufactured or when the electronic components are mounted on the shielded printed wiring board. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] [ Figure 1 ] Figure 1 is a schematic cross-sectional view of an example of a grounding member according to a first embodiment of the present invention;

[0077] [ Figure 2A ] Figure 2A This is a schematic diagram of an example of manufacturing a printed circuit board using a conventional grounding member;

[0078] [ Figure 2B ] Figure 2B This is a schematic diagram of an example of manufacturing a printed circuit board using a conventional grounding member;

[0079] [ Figure 2C ] Figure 2C This is a schematic diagram of an example of manufacturing a printed circuit board using a conventional grounding member;

[0080] [ Figure 3A ] Figure 3A This is a schematic diagram of an example of manufacturing a printed wiring board using the grounding member according to the first embodiment of the present invention;

[0081] [ Figure 3B ] Figure 3BThis is a schematic diagram of an example of manufacturing a printed wiring board using the grounding member according to the first embodiment of the present invention;

[0082] [ Figure 3C ] Figure 3C This is a schematic diagram of an example of manufacturing a printed wiring board using the grounding member according to the first embodiment of the present invention;

[0083] [ Figure 4 ] Figure 4 It is a schematic diagram of an example of a printed wiring board preparation process of a method for manufacturing a shielded printed wiring board using a grounding member according to a first embodiment of the present invention;

[0084] [ Figure 5 ] Figure 5 It is a schematic diagram of an example of a grounding member arrangement step of a method for manufacturing a shielded printed wiring board using the grounding member according to the first embodiment of the present invention;

[0085] [ Figure 6 ] Figure 6 It is a schematic diagram of an example of an electromagnetic wave shielding film arrangement step of a method for manufacturing a shielded printed wiring board using a grounding member according to a first embodiment of the present invention;

[0086] [ Fig. 7A ] Fig. 7A It is a schematic diagram of an example of a hot pressing process of a method for manufacturing a shielded printed wiring board using a grounding member according to a first embodiment of the present invention;

[0087] [ Figure 7B ] Figure 7B It is a schematic diagram of an example of a hot pressing process of a method for manufacturing a shielded printed wiring board using a grounding member according to a first embodiment of the present invention;

[0088] [ Figure 8 ] Figure 8 is a schematic cross-sectional view of an example of a grounding member according to a second embodiment of the present invention;

[0089] [ Fig.9A ] Fig.9A It is a schematic diagram of a state where the ground member according to the second embodiment of the present invention is arranged on the electromagnetic wave shielding film;

[0090] [ Fig. 9B ] Fig. 9B It is a schematic diagram of a state where the ground member according to the second embodiment of the present invention is arranged on the electromagnetic wave shielding film;

[0091] [ Fig. 10A ] Fig. 10A It is a schematic diagram of a case where the grounding member according to the second embodiment of the present invention is arranged on a shielded printed wiring board;

[0092] [ Fig. 10B ] Fig. 10B It is a schematic diagram of a case where the grounding member according to the second embodiment of the present invention is arranged on a shielded printed wiring board;

[0093] [ Fig.11 ] Fig.11 is a schematic cross-sectional view of an example of a grounding member according to a third embodiment of the present invention;

[0094] [ Fig. 12A ] Fig. 12A It is a schematic diagram of a case where the grounding member according to the third embodiment of the present invention is arranged on a shielded printed wiring board;

[0095] [ Fig. 12B ] Fig. 12B It is a schematic diagram of a case where the grounding member according to the third embodiment of the present invention is arranged on a shielded printed wiring board;

[0096] [ Fig.13A ] Fig.13A It is a schematic diagram of a case where the grounding member according to the third embodiment of the present invention is arranged on a shielded printed wiring board;

[0097] [ Fig. 13B ] Fig. 13B It is a schematic diagram of a case where the grounding member according to the third embodiment of the present invention is arranged on a shielded printed wiring board;

[0098] [ Fig. 13C ] Fig. 13C It is a schematic diagram of a case where the grounding member according to the third embodiment of the present invention is arranged on a shielded printed wiring board;

[0099] [ Fig.13D ] Fig.13D This is a schematic diagram showing a state where a ground member according to a third embodiment of the present invention is arranged on a shield printed wiring board.

[0100] Mode for carrying out the invention

[0101] The grounding member of the present invention will be described in detail below. However, the present invention is not limited to the following embodiments, and can be appropriately modified and applied within the scope of the present invention.

[0102] (First embodiment)

[0103] Hereinafter, a grounding member according to a first embodiment of the present invention will be described with reference to the drawings.

[0104] Figure 1 It is a schematic cross-sectional view of an example of the grounding member according to the first embodiment of the present invention.

[0105] like Figure 1 As shown, the grounding member 10 includes a conductive layer 20 and an adhesive layer 30 laminated on the conductive layer 20 .

[0106] Furthermore, the adhesive layer 30 includes a binder component 31 and hard particles 32 .

[0107] The thickness T30 of the adhesive layer 30 is 5 to 30 μm.

[0108] The grounding member 10 is used for manufacturing a shielded printed wiring board.

[0109] Here, first, problems encountered when manufacturing a shielded printed wiring board using a conventional grounding member will be described with reference to the drawings.

[0110] Figure 2A , Figure 2B and Figure 2C This is a schematic diagram of an example of manufacturing a printed wiring board using a conventional grounding member.

[0111] like Figure 2A As shown, a conventional grounding member 510 composed of a conductive layer 520 and an adhesive layer 530 laminated on the conductive layer 520 is arranged on a printed wiring board 550 . In the printed wiring board 550 , a printed circuit 552 is formed on a base film 551 , and the printed circuit 552 is covered with a cover film 553 .

[0112] At this time, the adhesive layer 530 of the conventional grounding member 510 is arranged on the printed wiring board 550 side.

[0113] Thereafter, the conventional ground member 510 is bonded and fixed to the printed wiring board 550 by heat pressing.

[0114] Electronic components are further mounted on the printed wiring board 550 including the grounding member 510. Solder is used when mounting the electronic components, and the printed wiring board 550 is heated when mounting the electronic components by solder reflow.

[0115] When the printed wiring board 550 is heated as described above, gas is generated from the adhesive layer 530 of the conventional grounding member 510, the cover film 553 of the printed wiring board 550, and the like. In addition, when the base film 551 of the printed wiring board 550 is formed of a highly hygroscopic resin such as polyimide, heating may cause water in the base film 551 to volatilize. Figure 2B As shown, the volatile components 560 generated from the adhesive layer 530 , the cover film 553 , and the base film 551 of the conventional grounding member 510 cannot pass through the conductive layer 520 of the conventional grounding member 510 , and thus accumulate between the conductive layer 520 and the adhesive layer 530 .

[0116] Therefore, when further rapid heating is performed, Figure 2C As shown, volatile components accumulated between the conductive layer 520 and the adhesive layer 530 of the conventional grounding member 510 may expand, thereby destroying the interlayer adhesion between the conductive layer 520 and the adhesive layer 530 of the conventional grounding member 510 .

[0117] Next, a case where a printed wiring board is manufactured using the grounding member according to the first embodiment of the present invention will be described with reference to the drawings.

[0118] Figure 3A , Figure 3B and Figure 3C This is a schematic diagram of an example of manufacturing a printed wiring board using the ground member according to the first embodiment of the present invention.

[0119] like Figure 3A As shown, the grounding member 10 including the conductive layer 20 and the adhesive layer 30 laminated on the conductive layer 20 is disposed on a printed wiring board 50 , in which a printed circuit 52 is formed on a base film 51 and the printed circuit 52 is covered by a cover film 53 .

[0120] At this time, the adhesive layer 30 of the ground member 10 is arranged on the printed wiring board 50 side.

[0121] Then, the ground member 10 is bonded and fixed to the printed wiring board 50 by heat pressing.

[0122] At this time, if Figure 3B As shown, the hard particles 32 contained in the adhesive layer 30 of the ground member 10 press the conductive layer 20 of the ground member 10 during the heat pressing, thereby forming holes and depressions 21 in the conductive layer 20 through which volatile components can pass.

[0123] As described above, when the ground member 10 is disposed on the printed wiring board 50 and thermally pressed, or when the electronic components are mounted on the printed wiring board 50 , volatile components are generated.

[0124] like Figure 3C As shown, the volatile component 60 can pass through the conductive layer 20 through the holes and recesses 21.

[0125] That is, it is possible to prevent the volatile component 60 from being accumulated between the conductive layer 20 and the adhesive layer 30 of the ground member 10 .

[0126] This can prevent the interlayer adhesion between the conductive layer 20 and the adhesive layer 30 of the ground member 10 from being damaged.

[0127] Next, each structure of the grounding member 10 will be described in detail.

[0128] (Conductive layer)

[0129] The material of the conductive layer 20 of the ground member 10 is not particularly limited, but is preferably formed of at least one selected from the group consisting of copper, silver, gold, and nickel.

[0130] In a shielded printed wiring board using ground member 10, conductive layer 20 of ground member 10 may be electrically connected to a ground circuit of the printed wiring board. In addition, in a shielded printed wiring board using ground member 10, conductive layer 20 may be connected to an external ground.

[0131] When the conductive layer of the ground member 10 is formed of at least one selected from the group consisting of copper, silver, gold, and nickel, the above materials have excellent conductivity, so the resistance value between the ground circuit and the external ground junction can be reduced.

[0132] The thickness of the conductive layer 20 of the ground member 10 is preferably 1 to 9 μm, more preferably 2 to 7 μm.

[0133] When the thickness of the conductive layer is less than 1 μm, the conductive layer has low strength and is easily damaged.

[0134] When the thickness of the conductive layer exceeds 9 μm, the conductive layer is too thick, and thus it is difficult to form holes or depressions through which the volatile components can pass by the hard particles.

[0135] (Adhesive layer)

[0136] In the ground member 10 , the thickness T30 of the adhesive layer 30 is 5 to 30 μm.

[0137] Furthermore, it is preferred that the thickness T30 of the adhesive layer 30 be 10 to 20 μm.

[0138] If the thickness of the adhesive layer is less than 5 μm, the bonding strength will be insufficient.

[0139] When the thickness of the adhesive layer exceeds 30 μm, the pressure of the hard particles pressing the conductive layer during hot pressing is dispersed, and holes and depressions through which the volatile components can pass cannot be formed in the conductive layer.

[0140] As described above, the Mohs hardness of the hard particles 32 included in the adhesive layer 30 is preferably 1.5 times or more, and more preferably 1.6 to 2.3 times, the Mohs hardness of the conductive layer 20 .

[0141] When the Mohs hardness of the hard particles 32 is 1.5 times or more the Mohs hardness of the conductive layer 20 , the hard particles 32 are easily embedded in the conductive layer 20 during hot pressing.

[0142] In this way, it is easy to form holes or depressions 21 in the conductive layer 20 through which volatile components can pass.

[0143] The Mohs hardness of the hard particles 32 is preferably 4-7, more preferably 5-7.

[0144] When the Mohs hardness of the hard particles 32 is 4 to 7, the hard particles 32 will not break during hot pressing, and holes and depressions 21 through which volatile components can pass can be easily formed in the conductive layer 20 .

[0145] The average particle size of the hard particles 32 is preferably 2.5 to 25 μm, more preferably 2.5 to 10 μm.

[0146] When the average particle size of the hard particles 32 is within this range, the holes and depressions 21 through which the volatile components can pass can be appropriately formed in the conductive layer 20 during hot pressing.

[0147] If the average particle size of the hard particles is less than 2.5 μm, it is difficult to form sufficiently large pores or depressions in the conductive layer during hot pressing, and volatile components are unlikely to pass through the conductive layer.

[0148] When the average particle size of the hard particles exceeds 25 μm, the holes and depressions formed in the conductive layer during hot pressing become large, and the strength of the conductive layer tends to decrease.

[0149] Preferably, the hard particles 32 are formed of silicon dioxide.

[0150] Silicon dioxide has a Mohs hardness of 7, which is hard enough and therefore is suitable for functioning as hard particles.

[0151] The material of the binder component 31 constituting the adhesive layer 30 is not particularly limited, and thermoplastic resins such as polystyrene, vinyl acetate, polyester, polyethylene, polypropylene, polyamide, rubber, acrylic, and thermosetting resins such as phenol, epoxy, polyurethane, polyurethane urea, melamine, and alkyd can be used.

[0152] Next, a method for manufacturing a shielded printed wiring board using the grounding member 10 will be described.

[0153] The method for manufacturing a shielded printed wiring board using the grounding member 10 includes: (1) a printed wiring board preparation step, (2) a grounding member placement step, (3) an electromagnetic wave shielding film placement step, and (4) a heat pressing step.

[0154] Hereinafter, each process will be described using the drawings.

[0155] Figure 4 This is a schematic diagram of an example of a printed wiring board preparation process in the method for manufacturing a shielded printed wiring board using the grounding member according to the first embodiment of the present invention.

[0156] Figure 5 It is a schematic diagram of an example of a ground member arrangement step of a method for manufacturing a shield printed wiring board using the ground member according to the first embodiment of the present invention.

[0157] Figure 6 It is a schematic diagram of an example of an electromagnetic wave shielding film arrangement process of the manufacturing method of the shielded printed wiring board using the ground member which concerns on the 1st Embodiment of this invention.

[0158] Fig. 7A and Figure 7B It is a schematic diagram of an example of a hot pressing process in the method for manufacturing a shielded printed wiring board using the ground member according to the first embodiment of the present invention.

[0159] (1) Printed circuit board preparation process

[0160] like Figure 4 As shown, in this step, a printed wiring board 50 composed of a base film 51, a printed circuit 52 including a ground circuit 52a disposed on the base film 51, and a cover film 53 covering the printed circuit 52 is prepared.

[0161] In the printed wiring board 50 , a part of the ground circuit 52 a is exposed through the opening 53 a of the cover film 53 .

[0162] The base film 51 and the cover film 53 are preferably made of engineering plastics. Examples of the engineering plastics include resins such as polyethylene terephthalate, polypropylene, cross-linked polyethylene, polyester, polybenzimidazole, polyimide, polyimide amide, polyetherimide, and polyphenylene sulfide.

[0163] Among the above-mentioned engineering plastics, polyphenylene sulfide films are preferred when flame retardancy is required, and polyimide films are preferred when heat resistance is required.

[0164] Furthermore, the thickness of the base film 51 is preferably 10 to 40 μm.

[0165] Furthermore, it is preferable that the thickness of the cover film 53 is 10 to 50 μm.

[0166] The material of the printed circuit 52 is not particularly limited, and may be copper foil, a cured conductive paste, or the like.

[0167] (2) Grounding component configuration process

[0168] Next, if Figure 5 As shown, the ground member 10 is disposed on the printed wiring board 50 so that the adhesive layer 30 of the ground member 10 is in contact with the cover film 53 of the printed wiring board 50 .

[0169] (3) Electromagnetic wave shielding film configuration process

[0170] Next, if Figure 6 As shown in FIG. 1 , an electromagnetic wave shielding film 40 including a conductive adhesive layer 41 and a metal thin film 42 laminated on the conductive adhesive layer 41 is prepared.

[0171] Then, the electromagnetic wave shielding film 40 is disposed on the printed wiring board 50 so that the conductive adhesive layer 41 of the electromagnetic wave shielding film 40 contacts the cover film 53 of the printed wiring board 50 and a part of the ground member 10 .

[0172] At this time, the electromagnetic wave shielding film 40 is arranged so that after the heat pressing process described later, the conductive adhesive layer 41 of the electromagnetic wave shielding film 40 fills the opening 53a of the printed wiring board 50 and contacts the ground circuit 52a.

[0173] Furthermore, the electromagnetic wave shielding film 40 is arranged so that the conductive adhesive layer 41 of the electromagnetic wave shielding film 40 contacts the conductive layer 20 of the ground member 10 after a heat pressing step described later.

[0174] The conductive adhesive layer 41 of the electromagnetic wave shielding film 40 is preferably composed of conductive particles and a resin.

[0175] The conductive particles are not particularly limited, but are preferably at least one selected from the group consisting of copper powder, silver powder, nickel powder, silver-coated copper powder, gold-coated copper powder, silver-coated nickel powder, and gold-coated nickel powder.

[0176] Resins that can be used include styrene resin compositions, vinyl acetate resin compositions, polyester resin compositions, polyethylene resin compositions, polypropylene resin compositions, imide resin compositions, amide resin compositions, acrylic resin compositions, phenol resin compositions, epoxy resin compositions, polyurethane resin compositions, melamine resin compositions, alkyd resin compositions, and the like.

[0177] The metal film 42 of the electromagnetic wave shielding film 40 may include a layer made of gold, silver, copper, aluminum, nickel, tin, palladium, chromium, titanium, zinc, etc., and preferably includes a copper layer.

[0178] From the viewpoint of conductivity and economic efficiency, copper is a suitable material for the metal film 42 .

[0179] Alternatively, the metal thin film 42 may include a layer made of an alloy of the above-mentioned metals.

[0180] Alternatively, a metal foil may be used as the metal thin film 42 , and the metal thin film 42 may be a metal film formed by sputtering, electroless plating, electroplating, or the like.

[0181] (4) Hot pressing process

[0182] Next, if Fig. 7A As shown, the printed wiring board 50 , the grounding member 10 and the electromagnetic wave shielding film 40 are heat-pressed to press the grounding member 10 and the electromagnetic wave shielding film 40 onto the printed wiring board 50 .

[0183] At this time, the conductive adhesive layer 41 of the electromagnetic wave shielding film 40 fills the opening 53a and is in contact with the ground circuit 52a.

[0184] Furthermore, the conductive adhesive layer 41 of the electromagnetic wave shielding film 40 contacts the conductive layer 20 of the ground member 10 .

[0185] like Figure 7B As shown, the electromagnetic wave shielding film 40 after heat pressing becomes the shielding layer 40a.

[0186] In addition, if Figure 7B As shown, in this process, the hard particles 32 contained in the adhesive layer 30 of the ground member 10 press the conductive layer 20 of the ground member 10 to form holes and depressions 21 in the conductive layer 20 through which volatile components can pass.

[0187] In the heat pressing process, volatile components are generated from the cover film 53 of the printed wiring board 50 and the adhesive layer 30 of the ground member 10 .

[0188] The volatile components can pass through the conductive layer 20 through the holes and recesses 21 .

[0189] That is, it is possible to prevent the volatile component 60 from being accumulated between the conductive layer 20 and the adhesive layer 30 of the ground member 10 .

[0190] This can prevent the interlayer adhesion between the conductive layer 20 and the adhesive layer 30 of the ground member 10 from being damaged.

[0191] The heating temperature in the hot pressing step is preferably 100 to 190°C, more preferably 120 to 170°C.

[0192] The pressing pressure in the hot pressing step is preferably 0.5 to 4.0 Pa, more preferably 2.0 to 3.0 Pa.

[0193] The shielded printed wiring board 70 can be manufactured through the above steps.

[0194] The above-mentioned shielded printed wiring board 70 is also a shielded printed wiring board of the present invention.

[0195] That is, Figure 7B As shown, the shielded printed wiring board 70 is composed of the printed wiring board 50 , the shielding layer 40 a , and the grounding member 10 .

[0196] The printed wiring board 50 is composed of a base film 51, a printed circuit 52 including a ground circuit 52a disposed on the base film 51, and a cover film 53 covering the printed circuit 52. The cover film 53 is formed with an opening 53a that exposes the ground circuit 52a.

[0197] The shielding layer 40 a is composed of a conductive adhesive layer 41 and a metal thin film 42 laminated on the conductive adhesive layer 41 .

[0198] Furthermore, the shield layer 40 a is disposed on the printed wiring board 50 so that the conductive adhesive layer 41 is in contact with the cover film 53 .

[0199] Furthermore, the conductive adhesive layer 41 fills the opening 53a of the cover film 53 and is in contact with the ground circuit 52a.

[0200] The ground member 10 includes a conductive layer 20 and an adhesive layer 30 laminated on the conductive layer 20 .

[0201] The ground member 10 is disposed on the printed wiring board 50 such that the adhesive layer 30 contacts the cover film 53 .

[0202] Therefore, the conductive layer 20 of the ground member 10 is electrically connected to the shield layer 40 a .

[0203] Furthermore, since the conductive adhesive layer 41 of the shield layer 40 a is in contact with the ground circuit 52 a , the conductive layer 20 of the ground member 10 is also electrically connected to the ground circuit 52 a .

[0204] Therefore, by electrically connecting the conductive layer 20 of the ground member 10 and an external ground (not shown), the ground circuit 52 a of the shield printed wiring board 70 and the external ground can be electrically connected.

[0205] Furthermore, the shielding layer of the shielded printed wiring board of the present invention may also be composed of an insulating adhesive layer and a metal thin film laminated on the insulating adhesive layer.

[0206] At this time, a plurality of conductive bumps can be formed on the metal film on the side of the insulating adhesive layer, or the metal film can be made into a convex shape, so that the conductive bumps or the convex-shaped metal film are in contact with the grounding circuit of the printed circuit board. In addition, by making the shielding layer contact with the conductive layer of the grounding component, and also making the conductive layer of the grounding component contact with the external grounding, etc., the grounding circuit of the shielded printed circuit board is electrically connected to the external grounding.

[0207] (Second embodiment)

[0208] Hereinafter, a grounding member according to a second embodiment of the present invention will be described with reference to the drawings.

[0209] Figure 8 It is a schematic cross-sectional view of an example of a grounding member according to a second embodiment of the present invention.

[0210] Figure 8 The illustrated grounding member 110 is similar in structure to the above-described grounding member 10 except that the adhesive layer 130 includes conductive particles 133 .

[0211] That is, Figure 8 As shown, the grounding member 110 is composed of a conductive layer 120 and an adhesive layer 130 laminated on the conductive layer 120 .

[0212] In addition, the adhesive layer 130 includes a binder component 131 , hard particles 132 , and conductive particles 133 .

[0213] The thickness T130 of the adhesive layer 130 is 5 to 30 μm.

[0214] Since the adhesive layer 130 of the ground member 110 includes the conductive particles 133 , the adhesive layer 130 functions as a conductive adhesive layer.

[0215] In the ground member 110 , the average particle diameter of the hard particles 132 is preferably smaller than the average particle diameter of the conductive particles 133 .

[0216] When the average particle diameter of the hard particles 132 is larger than the average particle diameter of the conductive particles 133, the hard particles 132 are easily exposed from the adhesive layer 130 of the ground member 110. Therefore, the adhesive layer 130 is easily lost in adhesion.

[0217] Furthermore, the average particle diameter of the conductive particles 133 of the ground member 110 is preferably 8 to 25 μm, and more preferably 10 to 25 μm.

[0218] The Mohs hardness of hard particles 132 of ground member 110 is preferably higher than the Mohs hardness of conductive particles 133 , and more preferably 1.2 times or more the Mohs hardness of conductive particles 133 .

[0219] When the Mohs hardness of the hard particles 132 is higher than that of the conductive particles 133 , even if the object to be bonded of the ground member 110 is soft, holes and depressions through which volatile components can pass are easily formed in the conductive layer 120 .

[0220] Furthermore, the Mohs hardness of the conductive particles 133 of the ground member 110 is preferably 5-9, more preferably 6-7.

[0221] The material of the conductive particles 133 is not particularly limited, and examples thereof include carbon, silver, copper, nickel, solder, aluminum, silver-coated copper filler obtained by silver-plating copper powder, and filler obtained by metal-plating resin balls, glass beads, etc., or a mixture of the above fillers, etc. Among them, silver-coated copper filler or nickel, which is relatively inexpensive and has excellent conductivity, is preferred.

[0222] The ground member 110 is sometimes arranged on an electromagnetic wave shielding film including a protective layer and a shielding layer laminated on the protective layer.

[0223] The case where the ground member 110 is disposed on the electromagnetic wave shielding film as described above will be described with reference to the drawings.

[0224] Fig.9A and Fig. 9B This is a schematic diagram showing a state in which a ground member according to a second embodiment of the present invention is disposed on an electromagnetic wave shielding film.

[0225] like Fig.9A As shown, the electromagnetic wave shielding film 180 provided with the ground member 110 includes a protective layer 181 and a shielding layer 182 laminated on the protective layer 181 .

[0226] When the ground member 110 is disposed on the electromagnetic wave shielding film 180 , the ground member 110 is disposed so that the adhesive layer 130 of the ground member 110 contacts the protective layer 181 of the electromagnetic wave shielding film 180 .

[0227] Afterwards, if Fig. 9B As shown, the pressurization is performed so that the conductive particles 133 of the ground member 110 penetrate the protective layer 181 of the electromagnetic wave shielding film 180 .

[0228] At this time, the hard particles 132 included in the adhesive layer 130 of the ground member 110 form holes and depressions 121 in the conductive layer 120 through which volatile components can pass.

[0229] The conductive layer 120 of the ground member 110 is connected to an external ground (not shown), and the shielding layer 182 of the electromagnetic wave shielding film 180 is electrically connected to a ground circuit (not shown) of a printed wiring board.

[0230] In this way, by using the ground member 110 , the ground circuit of the printed wiring board using the electromagnetic wave shielding film and the external ground can be electrically connected.

[0231] In the above case, it is preferable that the thickness of the binder component 131 of the adhesive layer 130 of the ground member 110 is smaller than the average particle diameter of the conductive particles 133 .

[0232] When the thickness of the binder component 131 of the adhesive layer 130 is smaller than the average particle diameter of the conductive particles 133 , the conductive particles 133 can surely penetrate the protective layer 181 of the electromagnetic shielding film 180 , so that the conductive particles 133 are in contact with the shielding layer 182 of the electromagnetic shielding film 180 .

[0233] In addition, the protective layer 181 and the shielding layer 182 constituting the electromagnetic wave shielding film 180 can use conventionally used ones.

[0234] The grounding member 110 may be disposed on a shielded printed wiring board.

[0235] The case where the grounding member 110 is arranged on the shielded printed wiring board as described above will be described with reference to the drawings.

[0236] Fig. 10A and Fig. 10B This is a schematic diagram showing a state where a ground member according to a second embodiment of the present invention is arranged on a shielded printed wiring board.

[0237] like Fig. 10A As shown, a shielded printed circuit board 170 provided with a grounding component 110 includes: a printed circuit board 150, a shielding layer 140a formed on a covering film 153, and a protective layer 143 formed on the shielding layer 140a, wherein the printed circuit board 150 is composed of a base film 151, a printed circuit 152 including a grounding circuit 152a arranged on the base film 151, and a covering film 153 covering the printed circuit 152.

[0238] The cover film 153 of the printed wiring board 150 is formed with an opening 153 a that exposes the ground circuit 152 a .

[0239] Furthermore, the shielding layer 140 a is composed of a conductive adhesive layer 141 and a metal thin film 142 laminated on the conductive adhesive layer 141 .

[0240] Furthermore, the shielding layer 140 a is arranged on the printed wiring board 150 so that the conductive adhesive layer 141 contacts the cover film 153 .

[0241] The conductive adhesive layer 141 fills the opening 153a of the cover film 153 and is in contact with the ground circuit 152a.

[0242] like Fig. 10A As shown, the ground member 110 is disposed on the shield printed wiring board 170 so that the adhesive layer 130 contacts the protective layer 143 .

[0243] Afterwards, if Fig. 10B As shown, the conductive particles 133 of the ground member 110 are pressed so as to penetrate the protective layer 143. Thus, the conductive particles 133 are brought into contact with the metal thin film 142.

[0244] At this time, the hard particles 132 included in the adhesive layer 130 of the ground member 110 form holes and depressions 121 in the conductive layer 120 through which volatile components can pass.

[0245] Furthermore, the conductive layer 120 of the ground member 110 is connected to an external ground (not shown).

[0246] In this way, the ground circuit 152 a of the shield printed wiring board 170 and the external ground can be electrically connected by using the ground member 110 .

[0247] In the above case, it is preferable that the thickness of the binder component 131 of the adhesive layer 130 of the ground member 110 is smaller than the average particle diameter of the conductive particles 133 .

[0248] When the thickness of the binder component 131 of the adhesive layer 130 is smaller than the average particle diameter of the conductive particles 133 , the conductive particles 133 can surely penetrate the protective layer 143 , so that the conductive particles 133 are in contact with the metal thin film 142 .

[0249] The preferred materials of the base film 151, printed circuit 152 (grounding circuit 152a), covering film 153, conductive adhesive layer 141, and metal film 142 of the shielding printed circuit board 170 are the same as the preferred materials of the base film 51, printed circuit 52 (grounding circuit 52a), covering film 53, conductive adhesive layer 41, and metal film 42 of the above-mentioned shielding printed circuit board 70.

[0250] The protective layer 143 of the shield printed wiring board 170 is preferably made of engineering plastics. Examples of the engineering plastics include polyethylene terephthalate, polypropylene, cross-linked polyethylene, polyester, polybenzimidazole, polyimide, polyimide amide, polyetherimide, polyphenylene sulfide and other resins.

[0251] Among the above-mentioned engineering plastics, polyphenylene sulfide films are preferred when flame retardancy is required, and polyimide films are preferred when heat resistance is required.

[0252] (Third embodiment)

[0253] Hereinafter, a grounding member according to a third embodiment of the present invention will be described with reference to the drawings.

[0254] Fig.11 It is a schematic cross-sectional view of an example of a grounding member according to a third embodiment of the present invention.

[0255] Fig.11 The illustrated grounding member 210 is similar in structure to the above-mentioned grounding member 10 except that a conductive protrusion 225 is formed therein.

[0256] That is, Fig.11 As shown, the grounding member 210 is composed of a conductive layer 220 and an adhesive layer 230 laminated on the conductive layer 220 .

[0257] Furthermore, the adhesive layer 230 includes a binder component 231 and hard particles 232 .

[0258] The thickness T230 of the adhesive layer 230 is 5 to 30 μm.

[0259] In addition, the adhesive layer 230 has insulating properties.

[0260] A conductive bump 225 is formed on the conductive layer 220 on the adhesive layer 230 side.

[0261] When the ground member 210 has the conductive protrusion 225 , the conductive layer 220 and the object to be bonded can be electrically connected via the conductive protrusion 225 .

[0262] The height of the conductive bump 225 is not particularly limited, but is preferably 10 to 40 μm, and more preferably 20 to 30 μm.

[0263] When the height of the conductive bump is less than 10 μm, it is difficult for the conductive bump to penetrate a protective layer of a shield printed wiring board described later.

[0264] When the height of the conductive bump exceeds 40 μm, it is difficult to control the conductive bump.

[0265] The material of the conductive bump 225 is not particularly limited, and the conductive bump 225 may be formed using a conductive paste composed of a resin composition and a conductive filler.

[0266] The resin composition of the conductive paste is not particularly limited, and thermoplastic resin compositions such as styrene resin compositions, vinyl acetate resin compositions, polyester resin compositions, polyethylene resin compositions, polypropylene resin compositions, imide resin compositions, amide resin compositions, and acrylic resin compositions, as well as thermosetting resin compositions such as phenol resin compositions, epoxy resin compositions, polyurethane resin compositions, melamine resin compositions, and alkyd resin compositions can be used.

[0267] The material of the resin composition may be one of the above materials alone or a combination of two or more of them.

[0268] The conductive filler of the conductive paste is not particularly limited, and may be metal fine particles, carbon nanotubes, carbon fibers, metal fibers, or the like.

[0269] In addition, when the conductive filler is metal particles, the metal particles are not particularly limited and can be silver powder, copper powder, nickel powder, solder powder, aluminum powder, silver-coated copper powder obtained by silver-plating copper powder, polymer particles coated with metal, glass beads, etc.

[0270] Among them, from the viewpoint of economic efficiency, copper powder or silver-coated copper powder which can be obtained at a low price is preferred.

[0271] The grounding member 210 may be disposed on a shielded printed wiring board.

[0272] The case where the grounding member 210 is arranged on the shielded printed wiring board as described above will be described with reference to the drawings.

[0273] Fig. 12A and Fig. 12B This is a schematic diagram showing a state where a ground member according to a third embodiment of the present invention is arranged on a shield printed wiring board.

[0274] like Fig. 12A As shown, a shielded printed circuit board 270 provided with a grounding component 210 includes: a printed circuit board 250, a shielding layer 240a formed on a covering film 253, and a protective layer 243 formed on the shielding layer 240a, wherein the printed circuit board 250 is composed of a base film 251, a printed circuit 252 including a grounding circuit 252a arranged on the base film 251, and a covering film 253 covering the printed circuit 252.

[0275] The cover film 253 of the printed wiring board 250 is formed with an opening 253 a that exposes the ground circuit 252 a .

[0276] Furthermore, the shielding layer 240 a is composed of a conductive adhesive layer 241 and a metal thin film 242 laminated on the conductive adhesive layer 241 .

[0277] Furthermore, the shielding layer 240 a is arranged on the printed wiring board 250 so that the conductive adhesive layer 241 contacts the cover film 253 .

[0278] The conductive adhesive layer 241 fills the opening 253a of the cover film 253 and is in contact with the ground circuit 252a.

[0279] like Fig. 12A As shown, the grounding member 210 is disposed on the shielding printed wiring board 270 such that the adhesive layer 230 contacts the protective layer 243 .

[0280] Afterwards, if Fig. 12B As shown, the conductive protrusion 225 of the grounding member 210 is pressed so as to penetrate the protective layer 243. Thus, the conductive protrusion 225 contacts the metal film 242. That is, the conductive protrusion 225 of the grounding member 210 penetrates the protective layer 243 and is electrically connected to the conductive layer 220 of the grounding member 210 and the shielding layer 240a.

[0281] At this time, the hard particles 232 included in the adhesive layer 230 of the ground member 210 form holes and depressions 221 in the conductive layer 220 through which volatile components can pass.

[0282] In addition, the conductive layer 220 of the ground member 210 is connected to an external ground (not shown).

[0283] In this way, the ground circuit 252 a of the shield printed wiring board 270 and the external ground can be electrically connected by using the ground member 210 .

[0284] Next, another embodiment of a shielded printed wiring board using the grounding member 210 will be described with reference to the drawings.

[0285] Fig.13A , Fig. 13B , Fig. 13C and Fig.13D This is a schematic diagram showing a state where a ground member according to a third embodiment of the present invention is arranged on a shield printed wiring board.

[0286] First, if Fig.13A As shown in FIG. 1 , a printed wiring board 350 is prepared which includes a base film 351 , a printed circuit 352 including a ground circuit 352 a disposed on the base film 351 , and a cover film 353 covering the printed circuit 352 .

[0287] In the printed wiring board 350 , a part of the ground circuit 352 a is exposed through the opening 353 a of the cover film 353 .

[0288] Next, if Fig. 13B As shown, the ground member 210 is disposed on the printed wiring board 350 so that the adhesive layer 230 is located above the opening 353 a of the cover film 353 of the printed wiring board 350 .

[0289] Next, if Fig. 13C As shown, an electromagnetic wave shielding film 340 composed of a conductive adhesive layer 341 and a metal thin film 342 laminated on the conductive adhesive layer 341 is arranged on the ground member 210 and the printed wiring board 350 in such a manner that the conductive adhesive layer 341 is on the lower side.

[0290] Next, if Fig.13D As shown, the grounding member 210 and the electromagnetic wave shielding film 340 are pressed onto the printed wiring board 350 by heat pressing to manufacture the shielding printed wiring board 370 .

[0291] At this time, the conductive protrusion 225 of the ground member 210 penetrates the adhesive layer 230 and contacts the ground circuit 352a.

[0292] Furthermore, the hard particles 232 included in the adhesive layer 230 of the ground member 210 form holes and depressions 221 in the conductive layer 220 through which volatile components can pass.

[0293] Furthermore, the electromagnetic wave shielding film 340 serves as a shielding layer 340 a .

[0294] Furthermore, the conductive adhesive layer 341 of the shield layer 340 a is in contact with the conductive layer 220 of the ground member 210 .

[0295] The conductive layer 220 of the grounding member 210 is connected to an external ground (not shown).

[0296] In this way, the ground circuit 352 a of the shield printed wiring board 370 and the external ground can be electrically connected by using the ground member 210 .

[0297] In the shielding printed circuit board 370, the preferred materials of the base film 351, the printed circuit 352 (grounding circuit 352a), the covering film 353, the conductive adhesive layer 341, and the metal film 342 are the same as the preferred materials of the base film 51, the printed circuit 52 (grounding circuit 52a), the covering film 53, the conductive adhesive layer 41, and the metal film 42 of the above-mentioned shielding printed circuit board 70.

[0298] Reference numerals

[0299] 10, 110, 210, 510 grounding components

[0300] 20, 120, 220, 520 Conductive layer

[0301] 21, 121, 221 holes, depressions

[0302] 30, 130, 230, 530 Adhesive layer

[0303] 31, 131, 231 Binder ingredients

[0304] 32, 132, 232 hard particles

[0305] 40, 180, 340 electromagnetic wave shielding film

[0306] 40a, 140a, 182, 240a, 340a shield

[0307] 41, 141, 241, 341 Conductive adhesive layer

[0308] 42, 142, 242, 342 metal film

[0309] 50, 150, 250, 350, 550 printed circuit boards

[0310] 51, 151, 251, 351, 551 basement membrane

[0311] 52, 152, 252, 352, 552 printed circuit

[0312] 52a, 152a, 252a, 352a Grounding circuit

[0313] 53, 153, 253, 353, 553 covering film

[0314] 53a, 153a, 253a, 353a opening

[0315] 60, 560 Volatile components

[0316] 70, 170, 270, 370 shielded printed circuit boards

[0317] 133 Conductive particles

[0318] 143, 181, 243 protective layer

[0319] 255 Conductive protrusion

Claims

1. A grounding member, comprising a conductive layer and an adhesive layer laminated on the conductive layer, characterized in that: The adhesive layer contains a binder component and hard particles. The thickness of the adhesive layer is 5 to 30 μm. The hard particles are heat-pressed to form holes and depressions in the conductive layer through which volatile components can pass.

2. The grounding member according to claim 1, characterized in that: The Mohs hardness of the hard particles is 1.5 times or more of the Mohs hardness of the conductive layer.

3. The grounding member according to claim 1, characterized in that: The Mohs hardness of the hard particles is 4-7.

4. The grounding member according to claim 1, characterized in that: The average particle size of the hard particles is 2.5 to 25 μm.

5. The grounding member according to claim 1, characterized in that: The hard particles are formed of silicon dioxide.

6. The grounding member according to claim 1, characterized in that: The conductive layer is formed of at least one selected from the group consisting of copper, silver, gold, and nickel.

7. The grounding member according to claim 1, characterized in that: The adhesive layer further includes conductive particles.

8. The grounding member according to claim 7, characterized in that: The average particle size of the hard particles is smaller than the average particle size of the conductive particles.

9. The grounding member according to claim 7, characterized in that: The Mohs hardness of the hard particles is higher than the Mohs hardness of the conductive particles.

10. The grounding member according to claim 7, characterized in that: The thickness of the binder component of the adhesive layer is smaller than the average particle diameter of the conductive particles.

11. The grounding member according to any one of claims 7 to 10, characterized in that: The grounding member is disposed on an electromagnetic wave shielding film, wherein the electromagnetic wave shielding film includes a protective layer and a shielding layer laminated on the protective layer. The adhesive layer is in contact with the protective layer, and the conductive particles penetrate the protective layer.

12. The grounding member according to any one of claims 7 to 10, characterized in that: The grounding component is arranged on a shielded printed circuit board, wherein: The shielded printed circuit board comprises: a printed circuit board, which is composed of a base film, a printed circuit including a grounding circuit arranged on the base film, and a cover film covering the printed circuit; a shielding layer, which is arranged on the cover film and is electrically connected to the grounding circuit; a protective layer, which is arranged on the surface of the shielding layer on the opposite side of the printed circuit side. The grounding member is arranged so that the adhesive layer is in contact with the protective layer and the conductive particles penetrate the protective layer.

13. The grounding member according to any one of claims 1 to 6, characterized in that: The adhesive layer has insulating properties, A conductive bump is formed on the conductive layer on the adhesive layer side.

14. A shielded printed circuit board, comprising: A printed circuit board is composed of a base film, a printed circuit including a ground circuit disposed on the base film, and a cover film covering the printed circuit; a shielding layer, disposed on the cover film and electrically connected to the ground circuit; The shielded printed circuit board is characterized in that: The shielded printed circuit board further comprises a grounding member as claimed in any one of claims 1 to 6, wherein the grounding member is arranged so that the adhesive layer of the grounding member is in contact with the cover film, The conductive layer of the grounding member is electrically connected to the shielding layer.

15. A shielded printed circuit board, comprising: The printed circuit board is composed of a base film, a printed circuit including a ground circuit arranged on the base film, and a cover film covering the printed circuit. an electromagnetic wave shielding film, arranged on the cover film, and composed of a conductive adhesive layer and a shielding layer laminated on the conductive adhesive layer, wherein the conductive adhesive layer is electrically connected to the ground circuit; The shielded printed circuit board is characterized in that: The shielded printed circuit board further comprises a grounding member as claimed in any one of claims 1 to 6, wherein the grounding member is arranged so that the adhesive layer of the grounding member is in contact with the cover film, The conductive layer of the ground member is electrically connected to the conductive adhesive layer of the electromagnetic wave shielding film.

16. A shielded printed circuit board, comprising: A printed circuit board is composed of a base film, a printed circuit including a ground circuit disposed on the base film, and a cover film covering the printed circuit; a shielding layer, disposed on the cover film and electrically connected to the ground circuit; A protective layer provided on a surface of the shielding layer opposite to the printed circuit side; The shielded printed circuit board is characterized in that: The shielded printed circuit board further comprises a grounding member as claimed in any one of claims 7 to 10, The grounding member is arranged so that the adhesive layer of the grounding member is in contact with the protective layer. The conductive particles of the ground member penetrate the protective layer and are electrically connected to the conductive layer of the ground member and the shielding layer.

17. A shielded printed circuit board, comprising: A printed circuit board is composed of a base film, a printed circuit including a ground circuit disposed on the base film, and a cover film covering the printed circuit; a shielding layer, disposed on the cover film and electrically connected to the ground circuit; A protective layer provided on a surface of the shielding layer opposite to the printed circuit side; The shielded printed circuit board is characterized in that: The shielded printed circuit board further comprises a grounding member as claimed in claim 13, The grounding member is arranged so that the adhesive layer of the grounding member is in contact with the protective layer. The conductive protrusion of the grounding member penetrates the protective layer and is electrically connected to the conductive layer of the grounding member and the shielding layer.

Images