The present application claims priority from Japanese Patent Application No. 2022-089179 filed on May 31, 2022, the contents of which are hereby incorporated by reference into this application.
The present invention relates to a method for producing a wiring circuit board.
A method is known in which in an assembly sheet including a plurality of wiring circuit boards and a supporting portion supporting the plurality of wiring circuit boards, the plurality of wiring circuit boards are separated from the supporting portion by cutting (ref: for example, Patent Document 1 below).
In the method described in Patent Document 1, since the separated plurality of wiring circuit boards after cutting are conveyed one by one, there is a problem that the process is complicated and the transportability is low.
The present invention provides a method for producing a wiring circuit board having excellent transportability.
The present invention (1) includes a method for producing a wiring circuit board including a first step of overlapping an assembly sheet including a plurality of wiring circuit boards and a supporting portion supporting the plurality of wiring circuit boards, and a supporting sheet for supporting the assembly sheet, in a thickness direction; after the first step, a second step of separating the plurality of wiring circuit boards from the supporting portion by cutting; and after the second step, a third step of conveying the assembly sheet including the plurality of wiring circuit boards separated from the supporting portion, while being supported by the supporting sheet.
According to this producing method, since the plurality of wiring circuit boards which are separated from the supporting portion are conveyed, while being supported by the supporting sheet, the transportability of the plurality of wiring circuit boards is excellent.
The present invention (2) includes the method for producing a wiring circuit board described in (1), wherein the supporting sheet has an opening portion penetrating the thickness direction; the assembly sheet includes a joint connecting the plurality of wiring circuit boards to the supporting portion; in the first step, the assembly sheet is overlapped with the supporting sheet so that the opening portion includes the joint when viewed in the thickness direction; and in the second step, the joint is cut.
According to this producing method, since in the second step, the joint is cut, it is possible to reliably and easily separate the wiring circuit board from the supporting portion.
Furthermore, since in the first step, the assembly sheet is overlapped with the supporting sheet so that the opening portion includes the joint when viewed in the thickness direction, in the second step, it is possible to suppress the contact of a cutting tool with the supporting sheet, and furthermore, to suppress the damage of the supporting sheet. Therefore, it is possible to suppress the occurrence of a foreign matter (dust generation) due to the above-described contact.
Further, since the damage of the supporting sheet is suppressed, after the third step, it is possible to reuse the supporting sheet.
The present invention (3) includes the method for producing a wiring circuit board described in (1) or (2), wherein the supporting sheet is a resin sheet.
According to this producing method, since the supporting sheet is the resin sheet, the handling of the supporting sheet is simple, and the transportability of the plurality of wiring circuit boards using the supporting sheet is further more excellent.
The present invention (4) includes the method for producing a wiring circuit board described in any one of (1) to (3), wherein both the wiring circuit board and the supporting portion include a metal supporting layer, an insulating layer, and a wiring layer in order toward one side in the thickness direction.
The present invention (5) includes the method for producing a wiring circuit board described in any one of (1) to (4), wherein a thickness of the assembly sheet is 500 μm or less.
The present invention (6) includes the method for producing a wiring circuit board described in any one of (2) to (5), wherein the plurality of opening portions are disposed at intervals, and a total opening ratio of the plurality of opening portions in the supporting sheet is 20% or more.
According to this producing method, since the total opening ratio of the plurality of opening portions is 20% or more, in the second step, it is possible to suppress the deformation of a portion facing the opening portion in the assembly sheet.
The present invention (7) includes the method for producing a wiring circuit board described in any one of (2) to (6), wherein a thickness of the supporting sheet is 150 μm or less.
According to this producing method, in the second step, it is possible to suppress the deformation of the portion facing the opening portion in the assembly sheet.
The present invention (8) includes the method for producing a wiring circuit board described in (6) or (7), wherein in the first step, the assembly sheet and the supporting sheet are disposed between a first mold having a punch, and a second mold disposed at intervals from the first mold in the thickness direction and having a hole so that the assembly sheet faces the first mold and the supporting sheet faces the second mold, and in the second step, the joint is punched by inserting the punch into the hole.
In the first step, when the assembly sheet and the supporting sheet are disposed between the first mold and the second mold so that the assembly sheet faces the first mold having the punch and the supporting sheet faces the second mold having the hole, in the second step, it is possible to improve the position accuracy at the time of punching.
On the other hand, in the second step, when the punch is inserted into the hole, in the assembly sheet, a portion in the outer vicinity of the punch and facing the opening portion is moved toward the opening portion. Then, the assembly sheet may be deformed due to the movement of the above-described portion of the assembly sheet.
However, since this producing method has a configuration of the above-described (6) or (7), it is possible to effectively suppress the above-described deformation.
The present invention provides a method for producing a wiring circuit board having excellent transportability.
One embodiment of a method for producing a wiring circuit board of the present invention is described with reference to
The method for producing a wiring circuit board includes a first step, a second step, and a third step in order. That is, in this producing method, the first step, the second step, and the third step are carried out in order.
As shown in
1.1.1 Assembly Sheet 1
As shown in
1.1.1.1 Plurality of Wiring Circuit Boards 11
The plurality of wiring circuit boards 11 are disposed inside a peripheral end portion in the assembly sheet 1. The plurality of wiring circuit boards 11 are disposed at spaced intervals from each other in the plane direction. In the present embodiment, the plurality of wiring circuit boards 11 are disposed in alignment each in a first direction and a second direction. The first direction and the second direction are included in the plane direction. The first direction and the second direction are perpendicular to each other. The first direction and the second direction are along the four rectangular sides of the assembly sheet 1.
As shown in
The metal supporting layer 111A is disposed in the other end portion of the wiring circuit board 11 in the thickness direction. The metal supporting layer 111A extends in the plane direction. Examples of a material for the metal supporting layer 111A include iron, stainless steel, copper, and copper alloy. A thickness of the metal supporting layer 111A is, for example, 1 μm or more, preferably 10 μm or more, and for example, 1000 μm or less, preferably 500 μm or less.
The insulating layer 112A is disposed on one surface of the metal supporting layer 111A in the thickness direction. The insulating layer 112A extends in the plane direction. In the present embodiment, the insulating layer 112A is a base insulating layer. An example of the material for the insulating layer 112A includes an insulating resin. An example of the insulating resin includes polyimide. The thickness of the insulating layer 112A is, for example, 1 μm or more, preferably 5 μm or more, and for example, 100 μm or less, preferably 50 μm or less.
The wiring layer 113A is disposed on one surface of the insulating layer 112A in the thickness direction. The wiring layer 113A extends in the plane direction. The wiring layer 113A has a pattern including a wiring and a terminal. Examples of the material for the wiring layer 113A include copper, silver, gold, iron, aluminum, chromium, and alloys of these. The thickness of the wiring layer 113A is, for example, 1 μm or more, preferably 3 μm or more, and for example, 50 μm or less, preferably 30 μm or less.
The cover insulating layer 114A is disposed in one end portion of the wiring circuit board 11 in the thickness direction. The cover insulating layer 114A is disposed on one surface of the insulating layer 112A in the thickness direction. Further, the cover insulating layer 114A covers the wiring of the wiring layer 113A. The cover insulating layer 114A extends in the plane direction. An example of the material for the cover insulating layer 114A includes an insulating resin. An example of the insulating resin includes polyimide. The thickness of the cover insulating layer 114A is, for example, 1 μm or more, preferably 5 μm or more, and for example, 100 μm or less, preferably 50 μm or less.
The thickness of the wiring circuit board 11 is, for example, 10 μm or more, preferably 25 μm or more, and for example, 1000 μm or less, preferably 500 μm or less. The thickness of the wiring circuit board 11 is the total thickness of the metal supporting layer 111A, the insulating layer 112A, the wiring layer 113A, and the cover insulating layer 114A.
1.1.1.2 Supporting Portion 12
As shown in
The supporting portion 12 includes at least one layer (preferably, multiple layers) selected from the group consisting of a metal supporting layer 111B, an insulating layer 112B, a wiring layer 113B, and a cover insulating layer 114B.
The metal supporting layer 111B, the insulating layer 112B, the wiring layer 113B, and the cover insulating layer 114B are the same layer as the metal supporting layer 111A, the insulating layer 112A, the wiring layer 113A, and the cover insulating layer 114A described above. The supporting portion 12 preferably has the same layer configuration as the wiring circuit board 11. That is, the supporting portion 12 preferably includes the metal supporting layer 111B, the insulating layer 112B, the wiring layer 113B, and the cover insulating layer 114B. As shown in
The metal supporting layer 111B of the supporting portion 12 is the same layer as the metal supporting layer 111A of the wiring circuit board 11. The insulating layer 112B of the supporting portion 12 is the same layer as the insulating layer 112A of the wiring circuit board 11. The wiring layer 113B of the supporting portion 12 is the same layer as the wiring layer 113A of the wiring circuit board 11. The wiring layer 113B may be also configured not to send a signal and/or ground current. The cover insulating layer 114B of the supporting portion 12 is the same layer as the cover insulating layer 114A of the wiring circuit board 11.
The supporting portion 12 has the same thickness as the wiring circuit board 11. The assembly sheet 1 has the same thickness as the wiring circuit board 11 and the supporting portion 12. Specifically, the thickness of the assembly sheet 1 is, for example, 10 μm or more, preferably 25 μm or more, and for example, 1000 μm or less, preferably 500 μm or less.
1.1.1.3 Joint 13
As shown in
The joint 13 includes at least one layer (preferably, multiple layers) selected from the group consisting of a metal supporting layer 111C, an insulating layer 112C, a wiring layer 113C, and a cover insulating layer 114C (not shown in
1.1.1.4 Groove 14
The groove 14 is disposed around each of the plurality of wiring circuit boards 11. In the present embodiment, the groove 14 has a generally rectangular frame shape when viewed in the thickness direction. The groove 14 penetrates the assembly sheet 1 in the thickness direction. The groove 14 separates the wiring circuit board 11 from the supporting portion 12 in the plane direction. Further, the grooves 14 are divided into a plurality pieces by the joint 13 when viewed in the thickness direction. In the present embodiment, the grooves 14 are a plurality of slits.
1.1.2 Supporting Sheet 2
The supporting sheet 2 has a thickness. The supporting sheet 2 extends in the plane direction. In the present embodiment, as shown in
1.1.2.1 Material for Supporting Sheet 2
Examples of the supporting sheet 2 include resin sheets, metal sheets, and ceramic sheets, and from the viewpoint of transportability of the wiring circuit board 11, a resin sheet is used. Examples of a resin of the resin sheet include polyester films and polyolefin films, and preferably, from the viewpoint of improving strength, a polyester film is used. Examples of the polyester film include polyethylene terephthalate films (PET film), polyethylene naphthalate films, and polybutylene terephthalate films, and preferably, from the viewpoint of reducing cost, a PET film is used.
1.1.2.2 Dimension of Supporting Sheet 2
A thickness T of the supporting sheet 2 (ref:
When the thickness T of the supporting sheet 2 is the above-described upper limit or less, in the second step to be described later, it is possible to suppress the deformation of a portion 16 (described later) facing an opening portion 21 in the assembly sheet 1.
1.1.2.3 Opening Portion 21
In the present embodiment, the supporting sheet 2 preferably has the opening portion 21. The opening portion 21 penetrates the supporting sheet 2 in the thickness direction. The plurality of opening portions 21 are disposed at intervals. As shown in
A total opening ratio of the plurality of opening portions 21 is, for example, 10% or more, preferably 20% or more, and for example, 50% or less, preferably 40% or less.
When the total opening ratio of the opening portion 21 is the above-described lower limit or more, in the second step to be described next, it is possible to suppress the deformation of the portion 16 facing the opening portion 21 in the assembly sheet 1. When the total opening ratio of the opening portion 21 is the above-described upper limit or less, in the third step, it is possible to suppress falling of the wiring circuit board 11 from the opening portion 21, and to improve the transportability of the wiring circuit board 11.
The total opening ratio of the plurality of opening portions 21 is a percentage of the area of the supporting sheet 2 when viewed in the thickness direction, and the total area of the plurality of opening portions 21 in the total area of the plurality of opening portions 21.
A ratio of the area of the joint 13 to the area of the opening portion 21 when overlapped in the thickness direction is, for example, 0.01 or more, preferably 0.015 or more, and for example, 0.3 or less.
In the first step, the assembly sheet 1 and the supporting sheet 2 are overlapped in the thickness direction. Specifically, in the first step, the above-described assembly sheet 1 and the supporting sheet 2 are overlapped in the thickness direction, thereby fabricating a laminated sheet 10. In the present embodiment, the laminated sheet 10 includes the supporting sheet 2 and the assembly sheet 1 in order toward one side in the thickness direction. That is, in the laminated sheet 10, the supporting sheet 2 and the assembly sheet 1 are disposed in order toward one side in the thickness direction. The assembly sheet 1 is disposed on one surface of the supporting sheet 2 in the thickness direction. The assembly sheet 1 is in contact with one surface of the supporting sheet 2 in the thickness direction.
The assembly sheet 1 is overlapped with the supporting sheet 2 so that the opening portion 21 includes the joint 13 when viewed in the thickness direction. At this time, the portion 16 facing the opening portion 21 in the assembly sheet 1 is exposed from the supporting sheet 2.
The one opening portion 21 corresponds to one corner portion 115.
In the first step, thereafter, the laminated sheet 10 is disposed between a first mold 3 and a second mold 4.
The first mold 3 has a first flat plate 31 and a punch 32. The first flat plate 31 has a thickness. The first flat plate 31 extends in the plane direction. The punch 32 extends along the thickness direction of the first flat plate 31. The punch 32 is capable of advancing and retracting toward the other side in the thickness direction (side of the second mold 4) with respect to the first flat plate 31. When the punch 32 advances and retracts, the punch 32 is guided by the first flat plate 31. A blade is provided in a front end portion (downstream-side end portion in an advancing direction) of the punch 32.
The plurality of punches 32 are provided corresponding to the plurality of joints 13. The first mold 3 is, for example, a metal mold.
The second mold 4 is disposed at intervals from the first mold 3 on the other side in the thickness direction thereof. The second mold 4 has a second flat plate 41 and a hole 42. The second flat plate 41 has a thickness. The second flat plate 41 extends in the plane direction. The second flat plate 41 is parallel to the first flat plate 31. The hole 42 penetrates the second flat plate 41 in the thickness direction. The plurality of holes 42 are provided corresponding to the plurality of punches 32. The hole 42 has a shape and dimension capable punching (cutting) the joint 13 when the punch 32 is inserted into the hole 42. The second mold 4 is, for example, a metal mold.
In the present embodiment, the laminated sheet 10 (the assembly sheet 1 and the supporting sheet 2) is disposed between the first mold 3 and the second mold 4 so that the assembly sheet 1 faces the first mold 3, and the supporting sheet 2 faces the second mold 4.
At this time, if necessary, a stripper plate 5 may be also disposed between the first flat plate 31 and the laminated sheet 10 (the assembly sheet 1). The stripper plate 5 has a second opening 51. The second opening 51 is overlapped with the opening portion 21 of the supporting sheet 2, the punch 32, and the hole 42 when viewed in the thickness direction. After cutting, when the punch 32 is pulled out of the hole 42, the stripper plate 5 is capable of peeling the punch 34 from the assembly sheet 1. The stripper plate 5 is, for example, a metal plate.
Then, the laminated sheet 10 and the stripper plate 5 are sandwiched between the first mold 3 and the second mold 4 in the thickness direction.
As shown in
Thereafter, though not shown, the punch 32 is pulled out of the hole 42.
As shown in
Separately, the supporting sheet 2 is reused.
According to this producing method, as shown in
According to this producing method, as shown in
Furthermore, since in the first step, the assembly sheet 1 is overlapped with the supporting sheet 2 so that the opening portion 21 of the supporting sheet 2 includes the joint 13 when viewed in the thickness direction. Therefore, in the second step, it is possible to suppress the contact of the punch 32 with the supporting sheet 2, and furthermore, to suppress the damage of the supporting sheet 2. Therefore, it is possible to suppress the occurrence of a foreign matter (dust generation) due to the above-described contact.
Further, since the damage of the supporting sheet 2 is suppressed, after the third step, it is possible to reuse the supporting sheet 2.
According to this producing method, when the supporting sheet 2 is the resin sheet, the handling of the supporting sheet 2 is simple, and the transportability of the plurality of wiring circuit boards 11 using the supporting sheet 2 is further more excellent.
When the total opening ratio of the plurality of opening portions 21 is below 20%, as shown in
However, according to this producing method, when the total opening ratio of the plurality of opening portions 21 is 20% or more, it is possible to increase the distance D between the inner peripheral surface of the supporting sheet 2, and the hole 42, in the second step, to reduce the stress applied to the portion 16, and to suppress the deformation of the portion 16 facing the opening portion 21 in the assembly sheet 1.
Further, when the thickness T of the supporting sheet 2 is above 150 μm, as shown in
However, according to this producing method, when the thickness T of the supporting sheet 2 is 150 μm or less, in the second step, it is possible to reduce the amount of movement of the portion 16 toward the hole 42, to reduce the stress applied to the portion 16, and to suppress the deformation of the portion 16 facing the opening portion 21 in the assembly sheet 1.
According to this producing method, as shown in
Further, in the second step, when the punch 32 is inserted into the hole 42, in the assembly sheet 1, the portion 16 in the outer vicinity of the punch 32 and facing the opening portion 21 is, as described above, moved toward the opening portion 21. Then, as shown in
However, according to this producing method, as described above, when the total opening ratio of the plurality of opening portions 21 is 20% or more and/or the thickness T of the supporting sheet 2 is 150 μm or less, it is possible to effectively suppress the deformation of the portion 16.
In each modified example below, the same reference numerals are provided for members and steps corresponding to each of those in the above-described one embodiment, and their detailed description is omitted. Further, each modified example can achieve the same function and effect as that of one embodiment unless otherwise specified. Furthermore, one embodiment and each modified example can be appropriately used in combination.
In the first modified example, though not shown, the supporting sheet 2 does not have the opening portion 21.
Comparing the first modified example to one embodiment, one embodiment is preferable. In one embodiment, it is possible to suppress the contact of the punch 32 with the supporting sheet 2, and furthermore, to suppress the damage of the supporting sheet 2. Therefore, it is possible to suppress the occurrence of the foreign matter (dust generation) due to the above-described contact. Furthermore, since it is possible to suppress the damage of the supporting sheet 2, it is possible to reuse the supporting sheet 2.
As shown in
In one embodiment, the first mold 3 is disposed at the upper side with respect to a fourth mold. However, though not shown, in the third modified example, the first mold 3 is disposed at the lower side with respect to the fourth mold.
Next, the present invention is further described based on Examples below. The present invention is however not limited by these Examples. The specific numerical values in mixing ratio (content ratio), property value, and parameter used in the following description can be replaced with upper limit values (numerical values defined as “or less” or “below”) or lower limit values (numerical values defined as “or more” or “above”) of corresponding numerical values in mixing ratio (content ratio), property value, and parameter described in the above-described “DESCRIPTION OF EMBODIMENTS”.
[First Step]
Each of the assembly sheet 1 and the supporting sheet 2 was fabricated. The thickness of the assembly sheet 1 was 60 μm. The thickness of the metal supporting layers 111A, 111B, and 111C was 30 μm, and the material was copper alloy. The thickness of the insulating layers 112A, 112B, and 112C was 10 μm, and the material was polyimide. The thickness of the wiring layers 113A, 113B, and 113C was 10 μm, and the material was copper. The thickness of the cover insulating layers 114A, 114B, and 114C was 10 μm, and the material was polyimide.
The thickness T of the supporting sheet 2 was 25 μm. The supporting sheet 2 was a PET film. The opening portion 21 had a circular shape when viewed in the thickness direction. The total opening ratio of the plurality of opening portions 21 in the supporting sheet 2 was 13%.
As shown in
The laminated sheet 10 was disposed between the first mold 3 and the second mold 4 so that the assembly sheet 1 faced the third mold 3, and the supporting sheet 2 faced the second mold 4. Subsequently, at the same time, the stripper plate 5 was disposed between the first flat plate 31 and the laminated sheet 10.
As shown in
[Second Step]
As shown in
[Third Step]
As shown in
The first step to the third step were carried out in the same manner as in Example 1. However, the thickness T of the supporting sheet 2 prepared in the first step, the diameter of the opening portion, and the total opening ratio were changed as described in Table 1.
[Evaluation]
Evaluation of Deformation
A deformation amount in the thickness direction in the portion 16 was measured. The deformation of the portion 16 was evaluated in accordance with the deformation amount as follows. The results are described in Table 1.
[Table 1]
While the illustrative embodiments of the present invention are provided in the above description, such is for illustrative purpose only and it is not to be construed as limiting the scope of the present invention. Modification and variation of the present invention that will be obvious to those skilled in the art is to be covered by the following claims.
Number | Date | Country | Kind |
---|---|---|---|
2022-089179 | May 2022 | JP | national |