Printed circuit board

Abstract

The printed circuit board comprises a base film having a main surface, and first and second wirings arranged on the main surface and extending in a first direction perpendicular to the normal of the main surface. The first and second wirings are adjacent to each other in a second direction perpendicular to the normal and the first direction. Each of the first and second wirings has a plurality of first parts, a plurality of second parts, and a plurality of connection parts. Each of the plurality of first parts extends in a first direction and is spaced apart and arranged in that first direction. Each of the plurality of second parts extends in a first direction and is positioned between two of the plurality of first parts that are adjacent to each other in the first direction. Each of the plurality of connection parts connects one of the plurality of first parts and one of the plurality of second parts that are adjacent to each other in the first direction.

Description

Technical Field

[0006] , , , , ,

[0001] The present disclosure relates to a printed wiring board.

Background Art

[0002] Japanese Patent Application Laid-Open No. 2018-92966 (Patent Document 1) describes a printed wiring board. The printed wiring board described in Patent Document 1 has a base film, and a first wiring and a second wiring disposed on the main surface of the base film.

[0003] Each of the first wiring and the second wiring extends in a first direction perpendicular to the normal of the main surface of the base film in a plan view, and is arranged at intervals in a second direction perpendicular to the normal and the first direction. Each of the first wiring and the second wiring has a first straight portion, a second straight portion, and a connecting portion. The connecting portion connects the first straight portion and the second straight portion.

[0004] The first straight portion has a first side surface and a second side surface forming end faces in the second direction. The second straight portion has a third side surface and a fourth side surface forming end faces in the second direction. The connecting portion has a fifth side surface and a sixth side surface forming end faces in the second direction. The first side surface is located between the third side surface and the fourth side surface in the second direction. The fourth side surface is located between the first side surface and the second side surface in the second direction. The fifth side surface is continuous with the first side surface. The sixth side surface is continuous with the fourth side surface. That is, the interval between the first wiring and the second wiring locally expands at a location where the connecting portions of the first wiring and the second wiring are adjacent to each other.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

[0006] The printed circuit board of this disclosure comprises a base film having a main surface, and first and second wirings arranged on the main surface and extending in a first direction perpendicular to the normal of the main surface. The first and second wirings are adjacent to each other in a second direction perpendicular to the normal and the first direction. Each of the first and second wirings has a plurality of first parts, a plurality of second parts, and a plurality of connection parts. Each of the plurality of first parts extends in the first direction and is spaced apart and arranged in the first direction. Each of the plurality of second parts extends in the first direction and is arranged between two of the plurality of first parts that are adjacent in the first direction. Each of the plurality of connection parts connects one of the plurality of first parts and one of the plurality of second parts that are adjacent to each other in the first direction. Each of the plurality of first parts has a first side surface and a second side surface that form an end face in the second direction. Each of the multiple second parts has a third side and a fourth side that form an end face in the second direction. One of the first and second sides is located between the third and fourth sides in the second direction. One of the third and fourth sides is located between the first and second sides in the second direction. Each of the multiple connecting parts has a fifth side and a sixth side that form an end face in the second direction and extend parallel to each other in a plan view. One of the fifth and sixth sides is connected to one of the first and second sides and is located between the third and fourth sides in the second direction. The other of the fifth and sixth sides is connected to one of the third and fourth sides and is located between the first and second sides in the second direction. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a plan view of the printed circuit board 100. [Figure 2] Figure 2 is a magnified view of a portion of Figure 1. [Figure 3] Figure 3 is a cross-sectional view taken along line III-III in Figure 2. [Figure 4] Figure 4 is a diagram illustrating the manufacturing process of the printed circuit board 100. [Figure 5]Figure 5 is a cross-sectional view illustrating the preparation process S1. [Figure 6] Figure 6 is a cross-sectional view illustrating the adhesive application process S21. [Figure 7] Figure 7 is a plan view of the photomask 52 used in the exposure process S22. [Figure 8] Figure 8 is a magnified view of a portion of Figure 7. [Figure 9] Figure 9 is an enlarged plan view illustrating the development process S23. [Figure 10] Figure 10 is a cross-sectional view illustrating the electroplating process S3. [Figure 11] Figure 11 is a cross-sectional view of a printed circuit board 100 according to Modification Example 1. [Figure 12] Figure 12 is an enlarged plan view of the printed circuit board 100 according to the modified example 2. [Figure 13] Figure 13 is an enlarged plan view of the printed circuit board 100 according to the third modified example. [Figure 14] Figure 14 is an enlarged plan view of the printed circuit board 100 according to the modified example 4. [Modes for carrying out the invention]

[0008] In the printed circuit board described in Patent Document 1, the sixth side surface is inclined relative to the fifth side surface in a plan view, so the width of the connecting portion in the second direction is locally reduced. In the printed circuit board described in Patent Document 1, the resist pattern used to form the wiring is formed by exposing the circuit while moving a single photomask. Furthermore, the orientation of the photomask when exposing the area where the first straight section is formed must be inclined relative to the orientation of the photomask when exposing the area where the second straight section is formed. Therefore, in the printed circuit board described in Patent Document 1, it is assumed that the sixth side surface is inclined relative to the fifth side surface in a plan view. The printed circuit board of this disclosure provides a printed circuit board that can prevent and suppress short circuits between adjacent wirings.

[0009] First, embodiments of this disclosure will be listed and described. (1) The printed circuit board according to the embodiment comprises a base film having a main surface, and first and second wirings arranged on the main surface and extending in a first direction perpendicular to the normal of the main surface. The first and second wirings are adjacent to each other in a second direction perpendicular to the normal and the first direction. Each of the first and second wirings has a plurality of first parts, a plurality of second parts, and a plurality of connection parts. Each of the plurality of first parts extends in the first direction and is spaced apart and arranged in the first direction. Each of the plurality of second parts extends in the first direction and is arranged between two of the plurality of first parts that are adjacent in the first direction. Each of the plurality of connection parts connects one of the plurality of first parts and one of the plurality of second parts that are adjacent to each other in the first direction. Each of the plurality of first parts has a first side surface and a second side surface that form an end face in the second direction. Each of the multiple second parts has a third side and a fourth side that form an end face in the second direction. One of the first and second sides is located between the third and fourth sides in the second direction. One of the third and fourth sides is located between the first and second sides in the second direction. Each of the multiple connection parts has a fifth side and a sixth side that form an end face in the second direction and extend parallel to each other in a plan view. One of the fifth and sixth sides is connected to one of the first and second sides and is located between the third and fourth sides in the second direction. The other of the fifth and sixth sides is connected to one of the third and fourth sides and is located between the first and second sides in the second direction. According to the printed circuit board of (1), short circuits between adjacent wirings can be suppressed.

[0010] (2) In the printed circuit board of (1), the first interval, which is the distance between the multiple first parts of the first wiring and the multiple first parts of the second wiring, and the second interval, which is the distance between the multiple second parts of the first wiring and the multiple second parts of the second wiring, may be smaller than the third interval, which is the distance between the multiple connection parts of the first wiring and the multiple connection parts of the second wiring.

[0011] (3) In the printed wiring board of (2), the first interval and the second interval may be 30 μm or less.

[0012] (4) In the printed wiring board of (1) to (3), the first length, which is the length of the first wiring in the first direction, and the second length, which is the length of the second wiring in the first direction, may be 1 m or more.

[0013] (5) In the printed wiring board of (1) to (4), the sum of the third length, which is the length of one of the plurality of first portions in the first direction, the fourth length, which is the length of one of the plurality of second portions in the first direction, and the fifth length, which is the length of one of the plurality of connection portions in the first direction, may be 100 mm or more and 500 mm or less.

[0014] (6) In the printed wiring board of (1) to (5), the machine direction of the base film may be perpendicular to the normal and inclined with respect to the first direction. According to the printed wiring board of (6), exposure can be performed with a single photomask.

[0015] (7) In the printed wiring board of (1) to (6), each of the first wiring and the second wiring may have a base layer disposed on the main surface and an electrolytic plating layer disposed on the base layer.

[0016] Next, details of embodiments of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant descriptions are not repeated. The printed wiring board according to the embodiment is referred to as a printed wiring board 100.

[0017] The configuration of the printed wiring board 100 will be described below. As shown in FIGS. 1, FIGS. 2 and FIGS. 3, the printed wiring board 100 has a base film 10 and a plurality of wirings 20.

[0018] The base film 10 has a main surface 11 and a main surface 12. The main surfaces 11 and 12 form the end faces of the base film 10 in the thickness direction. The thickness direction of the base film 10 is the direction of the normal to the main surface 11 (main surface 12). The main surface 12 is the opposite side of the main surface 11. The base film 10 is made of a flexible, electrically insulating material. For example, the base film 10 is made of polyimide.

[0019] Each of the multiple wirings 20 extends in a first direction 21 and is arranged in a second direction 22 with spacing between them. One of two adjacent wirings 20 may be called wiring 20A, and the other of the two may be called wiring 20B. The first direction 21 is perpendicular to the normal of the main surface 11 (main surface 12). The second direction 22 is perpendicular to the normal of the main surface 11 (main surface 12) and the first direction 21.

[0020] Each of the multiple wirings 20 has multiple first parts 23, multiple second parts 24, and multiple connectors 25. Each of the multiple first parts 23 extends in a first direction 21 and is spaced apart and aligned in the first direction 21. Each of the multiple second parts 24 extends in the first direction 21 and is positioned between two adjacent first parts 23. Each of the multiple connectors 25 connects one of the multiple first parts 23 and one of the multiple second parts 24 that are adjacent to each other.

[0021] Each of the multiple first parts 23 of wiring 20A is adjacent to each of the multiple first parts 23 of wiring 20B in the second direction 22. Each of the multiple second parts 24 of wiring 20A is adjacent to each of the multiple second parts 24 of wiring 20B in the second direction 22. Each of the multiple connection parts 25 of wiring 20A is adjacent to each of the multiple connection parts 25 of wiring 20B in the second direction 22.

[0022] Each of the multiple first parts 23 has a side 23a and a side 23b. Sides 23a and 23b form the end faces of the first part 23 in the second direction 22. Each of the multiple second parts 24 has a side 24a and a side 24b. Sides 24a and 24b form the end faces of the second part 24 in the second direction 22. Side 23a is located between side 24a and side 24b in the second direction 22. Side 24b is located between side 23a and side 23b in the second direction 22. In other words, each of the multiple first parts 23 is positioned to partially overlap each of the multiple second parts 24 in the second direction 22.

[0023] Each of the multiple connecting portions 25 has a side surface 25a and a side surface 25b. Side surfaces 25a and 25b form the end faces of the connecting portion 25 in the second direction 22. Side surface 25a is connected to side surface 23a. Side surface 25a is located between side surfaces 24a and 24b in the second direction 22 and is not connected to side surface 24a. Side surface 25b is connected to side surface 24b. Side surface 25b is located between side surfaces 23a and 23b in the second direction 22 and is not connected to side surface 23b. Therefore, the width of the connecting portion 25 in the second direction 22 is smaller than the width of the first portion 23 and the width of the second portion 24 in the second direction 22. To put this from another perspective, the distance (spacing 28) between the connection portion 25 of wiring 20A and the connection portion 25 of wiring 20B in the second direction 22 is greater than the distance (spacing 26) between the first portion 23 of wiring 20A and the first portion 23 of wiring 20B in the second direction 22, and the distance (spacing 27) between the second portion 24 of wiring 20A and the second portion 24 of wiring 20B in the second direction 22. In a plan view, the sides 25a and 25b are, for example, parallel to each other. As described above, side 23b is not connected to side 25b, and side 24a is not connected to side 25a. Therefore, in a plan view, steps are formed between side 23b and side 25b and between side 24a and side 25a.

[0024] Furthermore, side surface 23b may be located between side surface 24a and side surface 24b in the second direction 22, and side surface 24a may be located between side surface 23a and side surface 23b in the second direction 22. In this case, side surface 25a is connected to side surface 24a, and side surface 25b is connected to side surface 23b.

[0025] The spacings 26 and 27 are, for example, 30 μm or less. The spacings 26 and 27 may also be 15 μm or less. The length of the first part 23 in the first direction 21 is length 29, and the length of the second part 24 in the first direction 21 is length 30. The length of the connecting part 25 in the first direction 21 is length 31. The sum of lengths 29, 30, and 31 is, for example, 100 mm or more and 500 mm or less. The length of the wiring 20 in the first direction 21 is length 32. The length 32 is, for example, 1 m or more.

[0026] Each of the multiple wirings 20 has a base layer 40 and an electroplating layer 41. The base layer 40 is placed on the main surface 11. The base layer 40 has, for example, a seed layer and an electroless plating layer. The base layer 40 is formed of, for example, a nickel-chromium alloy. The electroless plating layer is formed of, for example, copper or a copper alloy. The electroplating layer 41 is placed on the base layer 40. The electroplating layer 41 is formed of, for example, copper or a copper alloy.

[0027] The mechanical direction 13 of the base film 10 is perpendicular to the normal of the main surface 11 (main surface 12) and inclined with respect to the first direction 21. The mechanical direction 13 of the base film 10 is the direction in which the base film 10 is stretched during the manufacturing process of the base film 10. The mechanical direction 13 of the base film 10 can be determined, for example, by measurement using an infrared spectrophotometer or by measurement using X-ray diffraction.

[0028] The method for manufacturing the printed circuit board 100 is described below. As shown in Figure 4, the method for manufacturing the printed circuit board 100 includes a preparation step S1, a resist pattern formation step S2, an electrolytic plating step S3, an etching step S4, and a piece formation step S5. The resist pattern formation step S2 is performed after the preparation step S1. The electrolytic plating step S3 is performed after the resist pattern formation step S2. The etching step S4 is performed after the electrolytic plating step S3. The piece formation step S5 is performed after the etching step S4.

[0029] As shown in Figure 5, in preparation step S1, a base film 10 is prepared. The base film prepared in preparation step S1 has an underlayer 40 formed on the main surface 11. In resist pattern formation step S2, a resist pattern 50 is formed on the underlayer 40. The resist pattern formation step S2 includes a bonding step S21, an exposure step S22, and a development step S23.

[0030] As shown in Figure 6, in the application process S21, a dry film resist 51 is applied to the base layer 40. In the exposure process S22, the dry film resist 51 is exposed. Exposure of the dry film resist 51 is performed using a single photomask 52, as shown in Figures 7 and 8. The photomask 52 has a plurality of openings 53 formed therein. When positioned on the base film 10, the plurality of openings 53 are perpendicular to the normal of the main surface 11 and extend in a direction inclined toward the machine direction 13. The plurality of openings 53 are perpendicular to the main surface 11 and are spaced apart in a direction perpendicular to the direction in which each of the plurality of openings 53 extends. Exposure of the dry film resist 51 is performed through the plurality of openings 53.

[0031] In the development process S23, the dry film resist 51 is developed. As a result, as shown in Figure 9, the dry film resist 51 becomes a resist pattern 50 having multiple openings 54. The underlying layer 40 is exposed through each of the multiple openings 54. Since the shape of the photomask 52 is transferred to form the openings 54, the photomask 52 has the same shape as the openings 54. From another point of view, the openings 53 have the same shape as the resist pattern 50.

[0032] Each of the multiple openings 54 extends in a first direction 21 and is arranged in a second direction 22 with spaces between them. One of two adjacent openings 54 may be called opening 54A, and the other of those two may be called opening 54B.

[0033] Each of the multiple openings 54 has a plurality of first portions 55, a plurality of second portions 56, and a plurality of connecting portions 57. Each of the plurality of first portions 55 extends in a first direction 21 and is spaced apart in the first direction 21. Each of the plurality of second portions 56 extends in a first direction 21 and is positioned between two adjacent first portions 55. Each of the plurality of connecting portions 57 connects one of the plurality of adjacent first portions 55 to one of the plurality of second portions 56.

[0034] Each of the multiple first portions 55 of the opening 54A is adjacent to each of the multiple first portions 55 of the opening 54B in the second direction 22. Each of the multiple second portions 56 of the opening 54A is adjacent to each of the multiple second portions 56 of the opening 54B in the second direction 22. Each of the multiple connecting portions 57 of the opening 54A is adjacent to each of the multiple connecting portions 57 of the opening 54B in the second direction 22.

[0035] Each of the multiple first parts 55 has a side 55a and a side 55b. Sides 55a and 55b form the end faces of the first part 55 in the second direction 22. Each of the multiple second parts 56 has a side 56a and a side 56b. Sides 56a and 56b form the end faces of the second part 56 in the second direction 22. Side 55a is located between side 56a and side 56b in the second direction 22. Side 56b is located between side 55a and side 55b in the second direction 22. In other words, each of the multiple first parts 55 is positioned to partially overlap each of the multiple second parts 56 in the second direction 22.

[0036] Each of the multiple connecting portions 57 has a side surface 57a and a side surface 57b. Side surfaces 57a and 57b form the end faces of the connecting portion 57 in the second direction 22. Side surface 57a is connected to side surface 55a. Side surface 57a is located between side surfaces 56a and 56b in the second direction 22 and is not connected to side surface 56a. Side surface 57b is connected to side surface 56b. Side surface 57b is located between side surfaces 55a and 55b in the second direction 22 and is not connected to side surface 55b. Therefore, the width of the connecting portion 57 in the second direction 22 is smaller than the width of the first portion 55 and the width of the second portion 56 in the second direction 22. From another perspective, the width of the resist pattern 50 located between the connection portion 57 of opening 54A and the connection portion 57 of opening 54B is greater than the width of the resist pattern 50 located between the first portion 55 of opening 54A and the first portion 55 of opening 54B, and the width of the resist pattern 50 located between the second portion 56 of opening 54A and the second portion 56 of opening 54B in the second direction 22. In plan view, the side surfaces 57a and 57b are parallel to each other.

[0037] As shown in Figure 10, in the electroplating step S3, an electroplated layer 41 is formed on the underlayer 40 exposed through multiple openings 54 by electroplating. After the electroplating step S3, the resist pattern 50 is removed. In the etching step S4, the underlayer 40 that was beneath the resist pattern 50 is removed by etching. In the piece formation step S5, the base film 10 is cut along the first direction 21 at multiple locations to obtain multiple printed circuit boards 100.

[0038] The effects of the printed circuit board 100 are explained below. When the spacing between wiring 20A and wiring 20B in the second direction 22 is smaller than the length of wiring 20 in the first direction 21 (length 32), the adhesion area between the resist pattern 50 and the base layer 40 becomes smaller, making the resist pattern 50 more prone to peeling. If the resist pattern 50 peels off, there is a risk that wiring 20A and wiring 20B will be short-circuited by the electroplating layer 41. In the printed circuit board 100, the spacing 28 is larger than spacings 26 and 27. This means that the width of the resist pattern 50 located between two adjacent openings 54 is locally larger. Therefore, in the printed circuit board 100, peeling of the resist pattern 50 and, consequently, the occurrence of short circuits between wiring 20A and wiring 20B are suppressed.

[0039] Furthermore, if the spacing between wiring 20A and wiring 20B in the second direction 22 becomes smaller than the length of wiring 20 in the first direction 21, the circulation of the etching solution in etching step S4 deteriorates. Poor circulation of the etching solution in etching step S4 can lead to insufficient removal of the underlying layer 40, causing a short circuit between wiring 20A and wiring 20B, or it can lead to a longer etching time, causing wiring 20 to become too thin. In the printed circuit board 100, the spacing 28 is larger than the spacings 26 and 27, so the spacing between wiring 20A and wiring 20B is locally larger, improving the circulation of the etching solution and suppressing the occurrence of the above-mentioned problems.

[0040] In the printed circuit board 100, the exposure process S22 is performed using a single photomask 52. Therefore, unlike when exposure is performed using multiple photomasks, the sides 57a and 57b (sides 25a and 25b) are formed parallel with high precision in a plan view. In other words, in the printed circuit board 100, the width of the connection portion 25 in the second direction 22 is prevented from becoming locally smaller. If the direction in which each of the multiple openings 53 in the photomask 52 extends is parallel to the machine direction 13, then another photomask other than the photomask 52 would be needed to form the structure of the end of the wiring 20. In the printed circuit board 100, the first direction 21 is inclined with respect to the machine direction 13, that is, the direction in which each of the multiple openings 53 in the photomask 52 extends is inclined with respect to the machine direction 13, so there is no need to use a photomask other than the photomask 52.

[0041] In the example above, the case in which the wiring 20 is formed by a semi-additive method was described, but the wiring 20 may also be formed by a subtractive method. That is, as shown in Figure 11, the wiring 20 does not have to have a base layer 40 and an electroplating layer 41. Also, as shown in Figure 12, the corners of the step between side surface 23b and side surface 25b and the corners of the step between side surface 24a and side surface 25a may be rounded.

[0042] As shown in Figures 13 and 14, the first portion 23 of each of the multiple wires 20 may be aligned in a direction inclined with respect to the first direction (a fourth direction, not shown), the second portion 24 of each of the multiple wires 20 may be aligned in the fourth direction, and the connecting portion 25 of each of the multiple wires 20 may be aligned in the fourth direction. In these examples as well, as shown in Figure 14, the corners of the step between side surface 23b and side surface 25b and the corners of the step between side surface 24a and side surface 25a may be rounded.

[0043] It should be understood that at least one configuration or feature described in each embodiment and example can be combined with other embodiments and examples, or modified in various ways. The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the claims rather than the embodiments described above, and all modifications within the meaning and scope of the claims are intended to be included. [Explanation of Symbols]

[0044] 10 Base film, 11 Main surface, 12 Main surface, 13 Machine direction, 20 Wiring, 20A, 20B Wiring, 21 First direction, 22 Second direction, 23 First part, 23a Side, 23b Side, 24 Second part, 24a Side, 24b Side, 25 Connection part, 25a Side, 25b Side, 26, 27, 28 Spacing, 29, 30, 31 Length, 32 Length, 40 Underlayer, 41 Electroplating layer, 50 Resist pattern, 51 Dry film resist, 52 Photomask, 53 Opening, 54 Opening, 54A, 54B Opening, 55 First part, 55a Side, 55b Side, 56 Second part, 56a Side, 56b Side, 57 Connection part, 57a Side, 57b Side, 100 Printed circuit board, S1 preparation process, S2 resist pattern formation process, S21 attachment process, S22 exposure process, S23 development process, S3 electroplating process, S4 etching process, S5 piece formation process.

Claims

1. A base film having a main surface, The device comprises a first wiring and a second wiring, which are arranged on the main surface and extend in a first direction perpendicular to the normal of the main surface, The first and second wirings are adjacent to each other in the normal and in a second direction perpendicular to the first direction, Each of the first and second wirings has a plurality of first parts, a plurality of second parts, and a plurality of connection parts. Each of the plurality of first parts extends in the first direction and is spaced apart and arranged in the first direction. Each of the plurality of second parts extends in the first direction and is positioned between two adjacent first parts in the first direction. Each of the plurality of connecting parts connects one of the plurality of first parts and one of the plurality of second parts that are adjacent to each other in the first direction. Each of the plurality of first portions has a first side surface and a second side surface that form an end face in the second direction, Each of the plurality of second portions has a third side surface and a fourth side surface that form an end face in the second direction, One of the first and second sides is located between the third and fourth sides in the second direction. One of the third and fourth sides is located between the first and second sides in the second direction. Each of the plurality of connecting portions has an end face in the second direction and a fifth and sixth side surface that extends parallel to each other in a plan view. One of the fifth and sixth sides is connected to one of the first and second sides, and is located between the third and fourth sides in the second direction. A printed circuit board in which the other of the fifth and sixth sides is connected to one of the third and fourth sides, and is located between the first and second sides in the second direction.

2. The printed circuit board according to claim 1, wherein the first interval, which is the distance between the plurality of first portions of the first wiring and the plurality of first portions of the second wiring, and the second interval, which is the distance between the plurality of second portions of the first wiring and the plurality of second portions of the second wiring, are smaller than the third interval, which is the distance between the plurality of connection portions of the first wiring and the plurality of connection portions of the second wiring.

3. The printed circuit board according to claim 2, wherein the first and second intervals are 30 μm or less.

4. The printed circuit board according to any one of claims 1 to 3, wherein the first length, which is the length of the first wiring in the first direction, and the second length, which is the length of the second wiring in the first direction, are 1 m or more.

5. The printed circuit board according to any one of claims 1 to 3, wherein the sum of the third length, which is the length of one of the plurality of first portions in the first direction, the fourth length, which is the length of one of the plurality of second portions in the first direction, and the fifth length, which is the length of one of the plurality of connecting portions in the first direction, is 100 mm or more and 500 mm or less.

6. The printed circuit board according to any one of claims 1 to 3, wherein the mechanical direction of the base film is perpendicular to the normal and inclined with respect to the first direction.

7. The printed circuit board according to any one of claims 1 to 3, wherein each of the first wiring and the second wiring has a base layer disposed on the main surface and an electroplating layer disposed on the base layer.

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