JP2002151804A - Printed wiring boards, component mounting boards and electronic equipment - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the outer shape accuracy of a divided wiring board. SOLUTION: A plurality of wiring regions on a substrate body on which printed wiring is formed are formed continuously so as to be dividable in divided regions between these wiring regions, and the plurality of wiring regions are formed of a coverlay film. In the printed wiring board that is covered and the divided area is not covered with the coverlay film, slits are formed at both ends on the substantially center line of the divided area in the substrate body, and the slit is formed on the substantially center line of the divided area. A dividing auxiliary hole penetrating the substrate body and having a diameter smaller than the width of the slit is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a printed wiring board,
More specifically, the present invention relates to a printed wiring board used by being divided (cut).

[0002]

2. Description of the Related Art Flexible printed wiring boards (hereinafter referred to as F)
PC) is used in various electronic devices because it is flexible and thin. The FPC is not only used as a cable in the electronic device, but also may be incorporated in the electronic device in a state where electric components are mounted by a method such as reflow. A board such as an FPC on which electric components are mounted in this manner is used by first mounting the electric components in a state where a plurality of substrates are connected and then cutting the individual substrates in order to increase mounting efficiency. There are many.

Here, as a method of cutting a plurality of connected substrates, there are generally known two methods of cutting with a tool and cutting by hand. Specifically, in the former method, a plurality of boards are connected to each other to mount an electric component on a connecting board in a sheet state, and the connecting board on which the electric component is mounted is pressed using a tool such as a press die. This is a method of cutting into individual substrates. The latter method is a method in which a rigid printed wiring board (hereinafter, referred to as PWB) among the connection boards on which electric components are mounted is divided by hand, and an FPC is torn by hand. The latter manual cutting method has an advantage that the cost can be reduced because a tool for cutting the connection substrate is not required.

FIG. 6 shows an FPC 31 in a first conventional example. Here, (A) is a front view of the FPC 31, and (B) is a cutaway view of the FPC 31.

A circuit pattern 33 is provided on the surface of the FPC 31.
a is formed. The virtual cutting line L31 drawn between the circuit patterns 33a is a line serving as a reference when cutting the FPC 31 (hereinafter, the same applies when referred to as a virtual cutting line). Further, slits 34 are formed at both ends of the FPC 31 on the virtual cutting line L31. As described above, by forming the slits 34 on both side ends of the FPC 31, the FPC 31 can be easily cut along the virtual cutting line L31. However, since there is no guide for cutting the FPC 31 along the virtual cutting line L31 between the two slits 34 formed on both side ends of the FPC 31, the FPC 31 is actually moved manually along the virtual cutting line L31. When trying to tear off, the FPC 31 is cut by the actual cutting line L3.
2 and separated into an FPC 31a and an FPC 31b. Here, the actual cutting line L32 is actually the FP
This is a line that indicates the contour of the cut surface generated when C31 is cut (hereinafter, the same is true when it is called an actual cut line). The actual cutting line L32 is an example, and when the FPC 31 is torn off by hand, the FPC 31 is cut by drawing various actual cutting lines.

FIG. 7 shows a PWB 41 in a second conventional example. Here, (A) is a front view of the PWB 41, and (B) is a cutaway view of the PWB 41.

The PWB 41 is a printed wiring board proposed in Japanese Utility Model Publication No. 58-28373.
A circuit pattern 43a is formed on the surface of the PWB 41. PWB is provided between the circuit patterns 43a.
A cutting assisting hole 45 penetrating through 41 is formed. The cutting assist hole 45 is a portion serving as a guide when cutting the PWB 41, and is arranged on the virtual cutting lines L41a and L41b. The virtual cutting line L in the PWB 41
Slits 46 are formed at both side ends on the upper side 41a and L41b.

Since the PWB 41 is easily cut along the virtual cutting lines L41a and L41b by the cutting auxiliary holes 45 and the slits 46, when the PWB 41 is cut along the virtual cutting lines L41a and L41b, the PWB4 is cut.
1 is cut substantially along the virtual cutting lines L41a and L41b to form PWB41a, PWB41b and PWB41.
c. Here, in the portion of the PWB 41 where the cutting assist hole 45 and the slit 46 are not formed,
Since it is not guided to be cut along the virtual cutting lines L41a and L41b, the actual cutting lines L42a and L42
b will be cut. The actual cutting line L4
2a and L42b are examples, and when the PWB 41 is torn off by hand, the PWB 41 is cut by drawing various actual cutting lines.

FIG. 8 shows an FPC 51 in a third conventional example. Here, (A) is a front view of the FPC 51, and (B) is an FPC 5 in the AA portion shown in (A).
1 is a sectional view of FIG. (C) is a cutaway view of the FPC 51.

The front and back surfaces of the FPC 51 are covered with a front coverlay 52.
a and the back cover lay 52b (both are referred to as cover lays 52). Inside the front cover lay 52a and the back cover lay 52b, a double-sided copper-clad board 54 whose front and back surfaces are covered with copper foil is arranged. Thus, a front circuit pattern 53a and a back circuit pattern 53b (both are referred to as circuit patterns 53) are provided. The double-sided copper-clad board 54 has a through-hole 55 formed therethrough. Through hole 5
Reference numeral 5 denotes a surface circuit pattern 5 whose inner peripheral surface is covered with metal.
3a and the back circuit pattern 53b are electrically connected.

On the front and back surfaces of the FPC 51, removed portions 52a 'and 52b' (both are referred to as removed portions 52 ') on which the coverlay 52 and the circuit pattern 53 are not formed are provided along the virtual cutting line L51. Have been. The removed portion 52 ′ is formed on the double-sided copper clad board 5 on which the circuit pattern 53 is formed.
4 is obtained by attaching a coverlay 52 that has been pressed, and the width W5 of the removed portion 52 ′ at this time is obtained.
1 has a relatively large width of about 1.0 mm for processing reasons and the like.

Furthermore, the virtual cutting line L in the FPC 51
Slits 56 are formed at both ends on the top 51.
The slit 56 guides the FPC 51 so as to be cut along the virtual cutting line L51.

The feature of the FPC 51 described above is that on the front and back surfaces of the FPC 51, the removed portions 52a 'and 52b' where the coverlay 52 and the circuit pattern 53 are not formed in the range of the width W51 are formed by the virtual cutting line L51. It is provided along. That is, the removal unit 52
By providing a ′ and 52b ′, the FPC 51 is easily cut along the virtual cutting line L51.

Therefore, the FPC 51 is connected to the virtual cutting line L51.
FPC 51 is cut within the range of width W51 in removal portion 52 ', and
51a and FPC 51b. Where FP
Since the C51 is not formed with a guide for cutting along the virtual cutting line L51 like the cutting auxiliary hole in the above-described second conventional example, the FPC 51 is formed with the actual cutting line L5.
2 is cut. The actual cutting line L5
2 is an example. When the FPC 51 is cut by hand,
51 is cut by drawing various real cutting lines.

[0015]

However, the first conventional example has the following disadvantages. That is, FPC
At 31, the actual cutting line L32 is not constant, and as shown in FIG. 6, the virtual cutting line L31 and the actual cutting line L32 may be largely shifted. When the virtual cutting line L31 and the real cutting line L32 are largely displaced, the FPC 31 becomes two FPs having different outer shapes.
It will be separated into C31a and FPC31b.

Here, when the FPC 31a whose cut portion is greatly expanded outward is incorporated into an electronic device, the FP
Since there is a high possibility that the large bulging portion outside the C31a will interfere with other components incorporated in the same electronic device, it is necessary to provide sufficient clearance when arranging other components. On the other hand, in the FPC 31b in which the shape of the cut portion is dented inward, the circuit pattern 33b is located near the cut portion, and there is a possibility that the circuit pattern 33a may be damaged depending on the cutting method of the FPC 31. is there. For this reason, the circuit pattern 33b cannot be arranged close to the virtual cutting line L31, thereby increasing the density of mounting and limiting the degree of freedom in arranging other internal components.

The second conventional example has the following disadvantages. That is, in the second conventional example, the cutting auxiliary holes 45 are formed in the slits 4 formed on both side ends of the PWB 41.
6 are formed at a predetermined interval on both sides with respect to the approximate center line of P.6.
Even if a and L42b deviate slightly from the virtual cutting lines L41a and L41b, the shape of the cut portion does not protrude from the fixed outer dimensions of the PWBs 41a and 41b. However, when the auxiliary cutting holes 45 are formed in this way, the auxiliary cutting holes 45 narrow the area where the circuit pattern is formed,
In addition to being restricted by circuit pattern design, the mounting density is high and the degree of freedom in arranging other components in the device is limited.
Also, the PW is generated by two virtual cutting lines L41a and L41b.
In order to cut B41, it is necessary to perform the cutting work of PWB 41 twice, and waste material 41c is generated.

On the other hand, when the structure of the PWB 41 is applied to an FPC, the FPC has a cutting auxiliary hole 45 serving as a cutting guide.
Is formed, the actual cutting line when the FPC is cut is more stable than the actual cutting line in the first conventional example, but there is no cutting guide in the portion where the cutting auxiliary hole is not formed. Therefore, the actual cutting line is not sufficiently stable.
Therefore, there is a possibility that a circuit pattern formed on the FPC may be damaged depending on how the FPC is cut.

Further, the third conventional example has the following disadvantages. That is, when the width W51 of the removed portion 52 ′ is 1.
Because of the relatively large width of about 0 mm, the actual cutting line L52 may deviate from the virtual cutting line L51 within the range of the width W51. That is, when the FPC 51 is cut, the shape of the cut portion becomes outwardly convex.
a, 51b may be formed. Such FP
If the C51a and 51b are incorporated in the electronic device, there is a high possibility that they will interfere with other components incorporated in the same electronic device. Therefore, it is necessary to provide sufficient clearance when arranging other components.

In order to increase the mounting density, etc.
The circuit patterns 53a and 53b may be formed as close as possible to the removed portion 52 '.
2 is attached to the double-sided copper-clad board 54,
Of about 0.3 mm, the circuit patterns 53a and 53b cannot be formed as close as possible to the removed portion 52 ', thereby increasing the mounting density and limiting the degree of freedom of other components in the device. Is done.

In view of the above-mentioned drawbacks of the prior art, it is an object of the present invention to reduce the deviation between the virtual cutting line and the actual cutting line and improve the external precision of the FPC, thereby reducing interference with other parts. Another object of the present invention is to achieve high-density mounting and the like by preventing the circuit pattern from being damaged while eliminating the same. It is another object of the present invention to further reduce the deviation between the virtual cutting line and the actual cutting line, thereby forming a circuit pattern to a position as close as possible to the virtual cutting line, thereby further increasing the mounting density. . Further, it is another object of the present invention to perform one cutting operation in which no waste material is generated at the time of cutting.

[0022]

According to a first aspect of the present invention, a plurality of wiring regions on a printed circuit board on which printed wiring is formed are divided into divided regions between the wiring regions. A plurality of wiring areas are covered with a coverlay film, and the divided areas are not covered with a coverlay film. Slits are formed at both ends on the line,
A dividing auxiliary hole having a diameter smaller than the width of the slit is formed on the center line of the divided region, penetrating the substrate main body.

That is, in the divided area in the substrate body,
By forming the slit and the division assisting hole, the substrate body can be easily divided. In addition, by making the diameter of the division assisting hole smaller than the width of the slit, the actual cutting line can be made closer to the virtual cutting line, so that the outer shape accuracy of the divided wiring board can be improved.

Incidentally, the diameter of the auxiliary dividing hole may be made substantially equal to the diameter of the through hole formed in the substrate body, or the auxiliary dividing hole may be formed by laser processing. If the division auxiliary hole is formed by laser processing, the division auxiliary hole having a smaller diameter can be formed, so that the external accuracy of the divided wiring board can be further improved.

According to a second aspect of the present invention, there is provided a printed wiring board in which a plurality of wiring regions on which printed wiring is formed on a substrate main body are continuously formed so as to be dividable in divided regions between these wiring regions. Slits are formed at both ends on a substantially center line of the divided region in the substrate body, and the wiring region is covered with a photosensitive coverlay film, and the photosensitive region is not covered with the photosensitive coverlay film. The width is formed smaller than the width of the slit.

That is, the divided area is not covered with the photosensitive coverlay film, and slits are formed at both ends of the divided area in the substrate body, so that the substrate body can be easily divided in the divided area. In addition, by making the width of the divided area smaller than the width of the slit, the deviation between the actual cutting line and the virtual cutting line can be reduced, so that the outer shape accuracy of the divided wiring board can be improved. Note that the width of the divided region can be set to about 0.3 mm or less.

Further, the wiring board obtained by dividing the printed wiring board of the present invention can be incorporated in an electronic device as a cable or an electronic component can be mounted on the electronic device as a component mounting board.

[0028]

(First Embodiment) FIG. 1 shows an FPC 1 according to a first embodiment of the present invention. Here, (A) is a plan view of the FPC1, and (B) is an AA shown in (A).
3 is a sectional view of the FPC 1 in FIG. (C) is FP
It is a sectional view of C1.

A front circuit pattern 3a and a back circuit pattern 3b (both are referred to as circuit patterns 3) formed by etching a copper foil are provided on the front and back surfaces of the FPC 1, respectively. Have been. In a portion of the FPC 1 that is sandwiched between the front circuit pattern 3a and the back circuit pattern 3b, a via hole 4 that penetrates the FPC 1 and has an inner peripheral surface plated with copper is formed. The via hole 4 electrically connects the front circuit pattern 3a and the back circuit pattern 3b, and is generally called a through hole.

The front circuit pattern 3a of the FPC 1
The portion where the back circuit pattern 3b is formed is covered with the front cover lay 2a and the back cover lay 2b (both are referred to as cover lay 2. The cover lay film according to the present invention). The portion covered by the coverlay 2 is the wiring area according to the present invention. On the other hand, near the virtual cutting line L1 on the front and back surfaces of the FPC 1, there are provided removal portions 2a 'and 2b' in which the front cover lay 2a and the back cover lay 2b are not formed (removal portions 2a 'and 2b in the FPC 1). The region 'is a divided region described in the claims of the present application). Here, the approximate center line of the removed portions 2a 'and 2b' is a virtual cutting line L1.

F is provided between the removing section 2a 'and the removing section 2b'.
Cutting assist holes 5 (division assist holes described in claims of the present application) penetrating PC1 are formed side by side on virtual cutting line L1. The cutting assist hole 5 is a portion serving as a guide for cutting the FPC 1 along the virtual cutting line L1, and is formed to have a diameter smaller than the width of the slits 9 formed on both side ends of the FPC 1 on the virtual cutting line L1. ing. In the present embodiment, the diameter of the cutting auxiliary hole 5 is the same as the diameter of the via hole 4. Here, if the formation of the cutting auxiliary hole 5 is performed not at the same time as the outer shape processing of the FPC 1 but at the same time as the formation of the via hole 4, the diameter of the cutting auxiliary hole 5 can be made the same as the diameter of the via hole 4. The diameter of the hole 5 can be made as small as 0.4 mm or less. In addition, the number of the cutting assist holes 5 can be appropriately set.

When the FPC1 is cut along the virtual cutting line L1, the FPC1 is cut along the real cutting line L2,
It is separated into PC1a and FPC1b.

FIG. 2 shows an example of a manufacturing process of the FPC 1 according to the present embodiment. The FPC 1 is manufactured through a sequence from (A) to (F). (A) is a member serving as a base material of the FPC 1, and is a cross-sectional view of a double-sided copper-clad plate 6 having a copper foil 3 ′ on the front and back surfaces. (B) shows a state in which a hole 7a to be a via hole 4 later and a hole 7b to be a cutting auxiliary hole 5 later are formed in the double-sided copper clad plate 6. The holes 7a and 7b are obtained by NC processing.
According to the C processing, the diameter of the holes 7a and 7b is φ0.3 to 0.4m.
m.

(C) shows the entire surface of the double-sided copper-clad plate 6 and the holes 7
This shows a state in which via-holes 4 for electrically connecting circuit patterns formed on the front and back surfaces of the double-sided copper clad plate 6 are formed by applying copper plating 8 to the inner peripheral surfaces of a and 7b. (D) Etching the surface of the double-sided copper clad plate 6 covered with the copper plating 8 to form a front circuit pattern 3a and a back circuit pattern 3b on the front and back surfaces of the double-sided copper clad plate 6, respectively.
Is formed. At the time of this etching,
Along with removing the copper foil 3 ′ and the copper plating 8 applied near the line that becomes the virtual cutting line L1 in the double-sided copper-clad plate 6,
The copper plating 8 applied to the inner peripheral surface of the via hole 4 located on the line serving as the virtual cutting line L1 is removed. Here, the via hole 4 from which the copper plating 8 has been removed becomes a cutting auxiliary hole 5.

(E) shows a front coverlay 2 which functions as a protective layer of the FPC 1 on each of the front and back surfaces of the double-sided copper clad board 6 on which the front circuit pattern 3a and the back circuit pattern 3b are formed.
FIG. 5A is a diagram in which a and a back cover lay 2b are attached. Here, the coverlay 2 is pressed as necessary,
The double-sided copper clad plate 6 is formed so as not to cover the vicinity of the virtual cutting line L1. By attaching the cover lay 2 formed in this way to the double-sided copper-clad plate 6, the removed portions 2a 'and 2b' extending in the direction of the virtual cutting line L1 are formed. (F) shows a state after punching of the outer shape with a press die, and the FPC 1 is completed with this.

The feature of the FPC 1 according to the present embodiment is that the removal portion 2 where the coverlays 2 and 3 are not formed near the virtual cutting line L1 on the front and back surfaces of the FPC 1 is provided.
a ′ and 2b ′ are provided, and
The point is that a cutting auxiliary hole 5 having a diameter smaller than the width of the slit 9 is provided along the virtual cutting line L1 between a ′ and the removing portion 2b ′.

As a result, the strength of the FPC 1 in the removal portions 2a 'and 2b' is reduced, and
Are provided side by side on the virtual cutting line L1 like a so-called perforation.
The strength of C1 becomes the weakest. Therefore, when the FPC 1 is to be cut by hand along the virtual cutting line L1, FIG.
As shown in (1), the FPC 1 is cut along the actual cutting line L2 passing through the cutting auxiliary hole 5.

In addition, as described above, the width of the auxiliary cutting hole 5 is smaller than the width of the slit 9, and specifically, the diameter of φ0.3 to 0.
The actual cutting line L2 is not greatly displaced from the virtual cutting line L1 because it is formed in a small diameter of 4 mm and is provided close to the perforation.

As described above, by obtaining a stable actual cutting line L2 that does not largely deviate from the virtual cutting line L1, the outer shape accuracy of the FPCs 1a and 1b obtained by dividing the FPC 1 is improved. In other words, the cutting of the FPC1 causes the FPC1a,
Since the FPCs 1b and 1b do not have a shape that bulges outward, the FPCs 1a and 1b do not interfere with other components when they are incorporated into an electronic device. There is no need to provide such a structure, and a high-density mounting can be realized. Furthermore, FP
Because C1a and 1b do not have a concave shape inside,
There is no fear that the circuit pattern 3 formed on the FPC 1 is damaged.

The cutting auxiliary hole 5 is provided with one virtual cutting line L.
Since they are formed side by side on one, only one cutting operation is required, and no waste material is generated.

(Second Embodiment) FIG. 3 shows an FPC 11 according to a second embodiment of the present invention. Here, (A) is an FPC
FIG. 11 is a plan view of the FPC 11, and FIG. 11B is a cross-sectional view of the FPC 11 taken along the line AA in FIG. (C) is an FPC
11 is a cutaway view of FIG.

A front circuit pattern 13a and a back circuit pattern 13b (both are referred to as circuit patterns 13) formed by etching a copper foil are provided on the front and back surfaces of the FPC 11, respectively. This circuit pattern 13
Is formed in the vicinity of the removing portions 12a 'and 12b' to be described later and in a portion sandwiched between two slits 9 to be described later.

In a portion of the FPC 11 sandwiched between the front circuit pattern 13a and the back circuit pattern 13b, there is formed a laser via hole 14 which penetrates the FPC 11 by laser processing and has an inner peripheral surface plated with copper. The laser via hole 14 electrically connects the front circuit pattern 13a and the back circuit pattern 13b,
Widely called a through hole.

The front circuit pattern 1 of the FPC 11
3a and the back circuit pattern 13b are formed on the front cover lay 12a and the back cover lay 1, respectively.
2b (both are called coverlays 12; the coverlay film described in the claims of the present application) (the portion of the FPC 11 covered by the coverlay 12 is the wiring area described in the claims of the present application). On the other hand, a virtual cutting line L on the front and back surfaces of the FPC 11
In the vicinity of 11 (substantially the center line of the divided region described in the claims of the present application), the removing portion 12 where the coverlay 12 is not formed is provided.
a ′ and 12b ′ are provided (areas of the removal parts 12a ′ and 12b ′ in the FPC 11 are divided areas according to the present invention). Here, a substantially center line of the removed portions 12a 'and 12b' is a virtual cutting line L1.

A cutting assisting hole 15 penetrating the FPC 11 is formed between the removing part 12a 'and the removing part 12b' along the virtual cutting line L11. Cutting auxiliary hole 15
Is a portion serving as a guide for cutting the FPC 11 along the virtual cutting line L11, and has a diameter smaller than the width of the slits 19 formed on both ends of the FPC1 on the virtual cutting line L1. In the present embodiment, the diameter of the cutting auxiliary hole 15 is the same as the diameter of the laser via hole 14. Here, if the formation of the cutting auxiliary hole 15 is performed not at the same time as the outer shape processing of the FPC 11 but at the same time as the formation of the laser via hole 14, the diameter of the cutting auxiliary hole 15 can be made equal to the diameter of the via hole 14. Further, by using the laser processing used for forming the laser via hole 14 for forming the cutting auxiliary hole 15, the cutting auxiliary hole 15 is formed.
Can be made as extremely small as 0.15 mm or less. In addition, the number of the cutting assistance holes 15 can be appropriately set.

When the FPC 11 is cut along the virtual cutting line L11, the FPC 11 is cut along the real cutting line L12 and separated into the FPC 11a and the FPC 11b.

FIG. 4 shows an example of a manufacturing process of the FPC 11 according to the present embodiment. The FPC 11 is manufactured through an order from (A) to (F).

FIG. 4A is a cross-sectional view of a double-sided copper clad plate 16 serving as a base material of the FPC 11. Double-sided copper clad board 16
Is obtained by applying copper foil 13 'on the front and back surfaces of a base plate 16'. (B) shows a state in which, of the copper foil 13 ′ applied to the surface of the double-sided copper-clad board 16, the copper foil 13 ′ in a portion to be the laser via hole 14 and the cutting auxiliary hole 15 later is removed by etching. .

(C) is to irradiate a laser to the portion from which the copper foil 13 ′ has been removed to remove the base 16 ′ of the double-sided copper-clad board 16 so that one end (the back side of the double-sided copper-clad board 16) The state where the non-through-hole 17 closed with the foil 13 ′ is formed is shown. At this time, the copper foil 13 ′ applied to the back surface of the double-sided copper-clad board 16 can be directly observed from the front side of the double-sided copper-clad board 16 through a non-through hole. By irradiating the double-sided copper-clad board 16 with the laser in this manner, the non-through hole 1 is formed.
7 can be made a very small diameter of 0.15 mm or less.

(D) shows a state in which copper plating 18 is applied to the entire surface of the double-sided copper-clad plate 16 and the inner peripheral surface of the non-through hole 17. By applying copper plating 18 to the inner peripheral surface of non-through hole 17, laser via hole 14 is formed.
(E) shows a state in which a front circuit pattern 13a and a back circuit pattern 13b are formed on the front and back surfaces of the double-sided copper clad board 16 by etching the front and back sides of the double-sided copper clad board 16 covered with the copper plating 18, respectively. ing. At the time of this etching, the copper foil 13 'and the copper plating 18 applied to the vicinity of the line serving as the virtual cutting line L11 of the double-sided copper clad board 16 are removed, and the laser via hole located on the line serving as the virtual cutting line L11 The copper plating 18 applied to the inner peripheral surface of the substrate 14 is removed. Here, the laser via hole 14 from which the copper plating 18 has been removed becomes the cutting auxiliary hole 15.

(F) is a diagram in which a front cover lay 12a and a back cover lay 12b functioning as a protective layer of the FPC 11 are attached to the front and back surfaces of the double-sided copper clad board 16, respectively.
Here, a photosensitive film is used as the coverlay 12. (G) is a virtual cutting line L11 of the coverlay 12.
Are exposed and subjected to chemical treatment, thereby removing portions 12a 'and 12b' extending in the direction of virtual cutting line L11.
Is formed.

In a commonly used polyimide coverlay, a removed portion is formed by pressing.
In the photosensitive cover lay used here, the removed portions 12a 'and 12b' can be formed by exposure and chemical treatment, so that fine processing can be performed. That is, in the processing of the coverlay made of polyimide, the width of the removed portion is limited to about 0.8 mm, while the processing of the photosensitive coverlay 12a is limited in the width of the removed portions 12a ′ and 12b ′. W11 can be processed to about 0.6 to 0.3 mm. In addition, while the displacement of the polyimide coverlay having the removed portion formed on the circuit pattern is about 0.3 mm, the removed portions 12a 'and 12a of the photosensitive coverlay are removed.
The displacement of b ′ with respect to the circuit pattern 13 occurs only about 0.1 mm.

As described above, when the photosensitive film is used as the cover lay 12, the removing portions 12a 'and 12b' are used.
Of the actual cutting line L12 with respect to the virtual cutting line L11 can be reduced.
a ′, 12b ′ can be suppressed within the small width W11. In addition, since the displacement of the cover lay 12 from the circuit pattern 13 can be reduced, even if the circuit pattern 13 is arranged in the vicinity of the removing portions 12a 'and 12b', the circuit lay 13 is displaced by the displacement of the cover lay 12.
Is not exposed on the surface.

(H) shows a state after the outer shape has been punched out by a press die, and the FPC 11 is completed with this.

The FPC 11 according to the present embodiment is characterized in that the photosensitive coverlay 12 and the copper foil 13 'are not formed on the virtual cutting line L11 on the front and back surfaces of the FPC 11, and the removed portions 12a' and 12b are not formed. And a cutting auxiliary hole 15 having a diameter smaller than the width of the slit 19 is provided between the removing portion 12a 'and the removing portion 12b'.

As a result, in addition to the fact that the strength of the FPC 11 is weakened in the removing portions 12a 'and 12b', the cutting assist holes 15 are provided along the virtual cutting line L11 like so-called perforations, so that the virtual cutting is performed. The strength of the FPC 11 is weakest in the portion along the line L11. Therefore, F
When trying to cut the PC 11 by hand along the virtual cutting line L11, the FPC 11 is cut along the actual cutting line L12 passing through the cutting auxiliary hole 15, as shown in FIG.

In the present embodiment, the removing units 12a ',
The width W11 of 12b 'is formed to be approximately 0.6 mm or less, and the cutting auxiliary hole 15 formed to have an extremely small diameter of 0.15 mm or less is provided near the perforation. Thereby, the deviation of the actual cutting line L12 from the virtual cutting line L11 can be reduced, and the outer shape accuracy of the cut FPCs 11a and 11b can be further improved.

That is, the FPC 11 obtained by dividing the FPC 11
Since the FPCs 11a and 11b do not have a shape that bulges outward, the FPCs 11a and 11b do not interfere with other components when they are incorporated into an electronic device. There is no need to provide a relief, and it is possible to realize a high-density mounting. Further, since the FPCs 11a and 11b do not have an indented shape, there is no fear that the circuit pattern 13 formed on the FPC 11 is damaged. In addition, since the cutting assist holes 15 are formed side by side on the virtual cutting line, only one cutting operation is required, and no waste material is generated.

Further, since the photosensitive cover lay 12 which can be finely processed and has a small displacement with respect to the circuit pattern 13 is used as the cover lay, the circuit pattern 13 is placed near the removing portions 12a 'and 12b'. Can be formed,
Further high-density mounting can be realized.

(Third Embodiment) FIG. 5 shows an FPC 21 according to a third embodiment of the present invention. Here, (A) is an FPC
21 is a plan view of FIG. 21, and FIG. 21B is a cross-sectional view of the FPC 21 taken along the line AA shown in FIG. (C) is an FPC
21 is a cutaway view of FIG.

On the front and back surfaces of the FPC 21, a front circuit pattern 23a and a back circuit pattern 23b (both are referred to as circuit patterns 23) formed by etching a copper foil are provided respectively. Have been. A part of the circuit pattern 23 is in the vicinity of the later-described removal units 22a ′ and 22b ′,
It is formed in a portion sandwiched between two slits 29.

The portion of the FPC 21 sandwiched between the front circuit pattern 23a and the back circuit pattern 23b has an FPC
1 and a via hole 2 with an inner peripheral surface plated with copper
4 are formed. The via hole 24 electrically connects the front circuit pattern 23a and the back circuit pattern 23b, and is generally called a through hole.

In the FPC 21, the front circuit pattern 2
The portions where the 3a and the back circuit pattern 23b are formed are covered with the front cover lay 22a and the back cover lay 22b (both are called cover lays 22. The cover lay film according to the present invention). FPC21
The portion covered by the coverlay 22 is a wiring area according to the present invention. On the other hand, in the vicinity of the virtual cutting line L21 (substantially the center line of the divided region described in the claims of the present application) on the front and back surfaces of the FPC 21, removal portions 22a ′ and 22b ′ not covered by the front coverlay 22a and the back coverlay 22b are provided. It is provided (the parts of the removal parts 22a 'and 22b' are divided areas according to the claims of the present application). Here, a substantially center line of the removed portions 22a 'and 22b' is a virtual cutting line L1. The width W21 of the removed portions 22a 'and 22b' is the same as the width of the slit 2 formed on both ends of the FPC 21 on the virtual cutting line L21.
9 is formed smaller than the width.

In this embodiment, a photosensitive coverlay is used as the coverlay 22. Therefore, as described in the second embodiment, the removing units 22a 'and 22a'
Since the fine processing for forming the width W21 of b ′ to about 0.2 mm can be performed, and the misalignment with the circuit pattern 23 can be reduced, the virtual cutting line L
A circuit pattern 23 can be arranged near 21.

The manufacturing process of the FPC 21 according to the present embodiment is substantially the same as the manufacturing process of the FPC 11 according to the second embodiment.
The only difference is that no 5 is formed.

The feature of the FPC 21 according to the present embodiment is that removing portions 22a 'and 22b' where the coverlay 22 and the circuit pattern 23 are not formed are provided near the virtual cutting line L21 on the front and back surfaces of the FPC 21. In addition, the width W21 of the removed portions 22a 'and 22b' is very small, about 0.2 mm. Here, it is clear that the strength of the FPC 21 becomes the weakest in the range of the width W21 of the removed portions 22a 'and 22b'.

Accordingly, when the FPC 21 is to be cut by hand along the virtual cutting line L21, as shown in FIG. 5C, the FPC 21 has the width W21 of the removed portions 22a 'and 22b'.
Is cut along the actual cutting line L22.
Here, the width W21 of the removed portions 22a 'and 22b' is 0.3
mm, the actual cutting line L22 does not significantly deviate from the virtual cutting line L21, and the outer shape accuracy of the FPC 21 can be improved.

That is, the FPC 21 obtained by dividing the FPC 21
Since the FPCs 21a and 21b do not have a shape that bulges outward, the FPCs 21a and 21b do not interfere with other components when they are incorporated into an electronic device. There is no need to provide a relief, and it is possible to realize a high-density mounting. Further, since the FPCs 21a and 21b do not have a concave shape inside, the circuit pattern 23 formed on the FPC 21
There is no danger of damage.

Since the coverlay 22 is made of a photosensitive coverlay which can be finely processed and has little misalignment with respect to the circuit pattern 23, the circuit pattern 23 is placed in a portion close to the removed portions 22a 'and 22b'. Accordingly, it is possible to further increase the mounting density. In addition, when the FPC 21 is cut, only one cutting operation is required, and no waste material is generated.

The flexible printed wiring board according to the first to third embodiments can be incorporated in an electronic device as a cable, or a component mounting board in which electronic components are mounted on the flexible printed wiring board can be used as an electronic device. Can be incorporated. The above is FPC
However, there is an effect when applied to PWB.
In that case, the resist may be configured in the same manner as the above coverlay.

[0071]

According to the printed wiring board of the first invention of the present application, the divisional area is not covered with the coverlay film, but the division auxiliary hole is formed substantially on the center line of the divisional area. By making the strength the weakest on the approximate center line, the substrate body can be easily divided along the approximate center line of the divided area.

Further, by forming the diameter of the division assisting hole smaller than the width of the slit, the deviation between the actual cutting line and the virtual cutting line (substantially the center line of the divided area) can be reduced. The accuracy of the outer shape of the substrate can be improved. In this way, if the outer shape accuracy of the divided wiring board can be improved, the circuit pattern is not damaged when the substrate body is cut, and when the divided wiring board is incorporated into an electronic device or the like, There is no interference with the cut part and other parts. For this reason, the mounting density can be increased and the degree of freedom in arranging other components in the device can be improved. Further, there is an effect that a single division operation in which no waste material is generated can be performed.

The auxiliary cutting hole can be formed by laser processing. In this case, the diameter of the auxiliary cutting hole can be made extremely small, so that the deviation between the actual cutting line and the virtual cutting line is further reduced. Therefore, the outer shape accuracy of the divided wiring board can be further improved. Also, the gap between the actual cutting line and the virtual cutting line can be reduced by covering the front and back surfaces of the substrate body with a photosensitive coverlay film and making the width of the divided region smaller than the width of the slit.

According to the printed wiring board of the second invention of the present application, by making the width of the divided area not covered by the photosensitive coverlay film smaller than the width of the slit,
The deviation between the actual cutting line and the virtual cutting line can be reduced, and the outer shape accuracy of the divided wiring board can be improved. In addition, there is also an effect that one division operation in which no waste material is generated can be performed.

[Brief description of the drawings]

FIG. 1A is a front view of an FPC 1 according to a first embodiment. (B) Sectional drawing of FPC1. (C) Cutaway view of FPC1.

FIG. 2 is a diagram showing a manufacturing process of the FPC 1 according to the first embodiment.

FIG. 3A is a front view of an FPC 11 according to a second embodiment. (B) Sectional drawing of FPC11. (C) Cutaway view of FPC11.

FIG. 4 is a view showing a manufacturing process of the FPC 11 according to the second embodiment.

FIG. 5A is a front view of an FPC 21 according to a third embodiment. (B) Sectional drawing of FPC21. (C) Cutaway view of FPC 21.

FIG. 6A is a front view of an FPC 31 in a first conventional example. (B) Cutaway view of FPC31.

FIG. 7A is a front view of a PWB 41 in a second conventional example. (B) Cutaway view of PWB41.

FIG. 8A is a front view of an FPC 51 in a third conventional example. (B) Sectional drawing of FPC51. (C) Cutaway view of FPC 51.

[Explanation of symbols]

1 FPC (Flexible Printed Wiring Board) 2 Coverlay (2a: Front Coverlay, 2b: Back Coverlay) 2a ', 2b' Remover 3 Circuit Pattern (3a: Front Circuit Pattern, 3b: Back Circuit Pattern) 3 'Copper Foil 4 Via hole 5 Cutting auxiliary hole 6 Double-sided copper-clad plate 7a, 7b Hole 8 Copper plating L1 Virtual cutting line L2 Actual cutting line

Claims (11)

[Claims] A plurality of wiring regions on a substrate main body on which printed wiring is formed are formed continuously so as to be dividable in divided regions between the wiring regions, and the plurality of wiring regions are formed of a coverlay film. In the printed wiring board covered with the divided region and not covered with the coverlay film, slits are formed at both ends on the substantially center line of the divided region in the substrate main body, and the slit is formed on the substantially center line of the divided region. A divided auxiliary hole having a diameter smaller than the width of the slit is formed through the substrate main body. 2. A printed wiring is formed on both sides of the substrate body, and a through-hole for electrically connecting these printed wirings is formed. The diameter of the auxiliary dividing hole is equal to the diameter of the through-hole. The printed wiring board according to claim 1, wherein the diameter is substantially equal to the diameter. 3. The printed wiring board according to claim 1, wherein the division assisting hole is formed by laser processing. 4. The printed wiring board according to claim 1, wherein the cover lay film is a photosensitive film, and the width of the divided region is formed to be approximately 0.6 mm or less. 5. A width of the divided region is formed smaller than a width of the slit, and a part of the printed wiring is formed in a region other than the divided region in a region between the slits in the substrate body. The printed wiring board according to claim 1, wherein 6. A printed wiring board in which a plurality of wiring regions on a substrate main body on which printed wiring is formed are continuously formed so as to be dividable in divided regions between the wiring regions, wherein the divided region in the substrate main body is provided. Slits are formed at both ends on the approximate center line, and the wiring area is covered with a photosensitive coverlay film, and the width of the divided area where the photosensitive coverlay film is not covered is the width of the slit. A printed wiring board characterized by being formed smaller. 7. The printed wiring board according to claim 6, wherein the width of the divided area is formed to be approximately 0.6 mm or less. 8. The printed wiring according to claim 6, wherein a part of the printed wiring is formed in a region other than the divided region in a region between the slits in the substrate main body. substrate. 9. A component mounting board, wherein an electronic component is mounted on a wiring board obtained by dividing the printed wiring board according to claim 1. 10. An electronic device using the component mounting board according to claim 9. 11. An electronic device using a printed circuit board obtained by dividing the printed wiring board according to claim 1.