JPH09260798A - Flexible printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible printed wiring board with a simple structure, allowing NG holes to be bored in an accurate shape at accurate positions. SOLUTION: This wiring board has a sheet-like base 10, having a resin- impregnated glass cloth and conductor pattern formed on the surface of this base. If it is decided to be a defective product, an NG hole 40 is bored. In this case, at the bored NG hole 40 on the surface of the base 10, a dummy pattern having a larger aperture 30 than the hole 40 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible printed wiring board, and more particularly to a sheet-like base material obtained by impregnating glass cloth with a resin, and a conductor pattern formed on the surface of the base material. The present invention relates to a flexible printed wiring board in which an NG hole is formed when a defective product is recognized.

[0002]

2. Description of the Related Art In a flexible printed wiring board having a sheet-like base material obtained by impregnating glass cloth with a resin and a conductor pattern formed on the surface of the base material,
When a non-defective product is inspected by a continuity inspection or the like of the conductor pattern and it is determined that the product is defective, for example, a conductor pattern formation region as shown in FIG. 7 or a conductor pattern formation as shown in FIG. There is a case where an NG hole is bored at a predetermined portion outside the region, and this flexible printed wiring board is clearly indicated as a defective product.

[0003]

However, the conventional flexible printed wiring board has the following problems.

The NG hole is bored by a tool such as a punch pin, but the cutting edge of the tool is worn by the glass cloth which constitutes the base material of the flexible printed wiring board. And, depending on the tool whose cutting edge is worn, N
It becomes impossible to form the G hole in an accurate shape.
That is, as shown in FIG. 9A, if the tool is in an initial state, it is possible to form an NG hole having an accurate shape. However, when the cutting edge of the tool is worn out, FIG.
As shown in, it becomes impossible to form an NG hole having an accurate shape.

If the NG hole is not formed in an accurate shape as described above, for example, when the NG hole is automatically detected by an optical device, the NG hole is not detected and the NG hole is not formed. There is a possibility that the installed product will be judged as a non-defective product. In particular, in a base material obtained by impregnating glass cloth with a resin, so-called fluff that the fibers of the glass cloth project into the NG hole is generated, as shown in FIG. The problem that a hole cannot be detected remarkably occurs.

On the other hand, in the NG hole, the site to be drilled is specified by the customer. However, when the NG hole is manually drilled, the NG hole is drilled in the wrong site. There is a risk. A defective product in which an NG hole is drilled at a site different from the designated site is determined to be a non-defective product in which the NG hole is not drilled at the delivery destination, and may be leaked to the market. is there. Such outflow of defective products to the market is a very serious problem for manufacturers, and must be prevented by all means. To this end, NG holes must be secured at the site to be drilled. Must be drilled in.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a flexible printed wiring board capable of forming an NG hole in an accurate shape at an accurate portion. , Is to provide by a simple structure.

[0008]

Means for Solving the Problems In order to solve the above problems, the means adopted by the present invention will be described with reference to the reference numerals used in the drawings. A flexible sheet having a sheet-shaped base material 10 impregnated with a resin and a conductor pattern 20 formed on the surface of the base material 10 and having an NG hole 40 formed when a defective product is recognized. In a printed wiring board, the base material 1
At the site where the NG hole 40 is drilled on the surface of 0,
The flexible printed wiring board is characterized in that a dummy pattern 30 having a diameter larger than that of the NG hole 40 is provided.

Next, the invention of claim 2 is that "N
The flexible printed wiring board according to claim 1, wherein a primary hole 50 having a diameter larger than that of the G hole 40 is provided, and the dummy pattern 30 is provided so as to cover the primary hole 50.

The flexible printed wiring board according to each of the present invention operates as follows with the above configuration.

The base material 10 is formed by a tool 70 such as a punch pin.
When the NG hole 40 is formed in the hole, the cutting edge of the tool 70 first contacts the dummy pattern 30, and then the base material 10
It penetrates the inside and finally penetrates the base material 10.
When coming into contact with the dummy pattern 30 and entering the inside of the base material 10, the dummy pattern 30 is slightly rolled up so that the base material 10
Invade. Therefore, the cutting edge of the tool 70 is protected by the dummy pattern 30 as much as the dummy pattern 30 is rolled up and enters the base material 10.
Wear when punching is reduced. Therefore, the life of the tool 70 is extended, and even if the tool 70 is used for many years,
It is possible to form the NG hole 40 having an accurate shape.

Further, even if the fibers of the glass cloth constituting the base material 10 cause fluffing in the NG holes 40,
This fluff will be pushed down by the dummy pattern 30 that has been caught, as shown in FIG.
It does not project into the G hole 40, and can be detected as the NG hole 40 even by an optical automatic detection device.

On the other hand, since the dummy pattern 30 is provided in the portion where the NG hole 40 is to be bored, when the NG hole 40 is bored manually, for example, the portion to be bored becomes clear, which is incorrect. There is no possibility of forming the NG hole 40 in the part. Further, for example, when the presence / absence of the NG hole 40 is visually inspected for the delivery destination, the dummy pattern 30 reveals the portion to be inspected for the presence / absence of the NG hole 40, and the workability of the inspection is improved.

Particularly, in the flexible printed wiring board according to the second aspect of the present invention, a primary hole 50 having a diameter larger than that of the NG hole 40 is formed at a portion of the substrate 10 where the NG hole 40 is formed. The dummy pattern 30 is provided so as to cover the primary hole 50. Therefore, when the NG hole 40 is bored, it is not necessary to punch the base material 10 with the tool 70 such as a punch pin, and only the dummy pattern 30 needs to be punched out, and it is possible to further reduce the wear of the cutting edge. Become.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of a flexible printed wiring board according to the present invention will be described in detail with reference to the drawings.

First, FIG. 1 shows an example of a flexible printed wiring board according to the invention of claim 1. In this flexible printed wiring board, a plurality of conductive patterns 20 as individual flexible printed wiring boards are formed on the surface of the base material 10 integrally formed in a long shape, and the entire base material 10 is formed. A plurality of pieces are integrally handled by winding them in a roll. Then, the conductor pattern 20 is inspected for conduction and the like for each individual flexible printed wiring board, and if it is a defective product, the NG hole 4 is placed here.
0 is provided.

The substrate 10 is based on glass cloth,
Epoxy resin, triazine resin,
The resin is impregnated with a resin such as polyester resin or polyimide resin. The conductor pattern 20 as an individual flexible printed wiring board is formed of copper or the like on the surface of the base material 10. Further, the base material 10 has sprocket holes 60 for feeding the long base material 10, chip holes (not shown) for mounting electronic components such as semiconductor chips to be mounted, the mounted electronic components and conductor patterns. Through holes such as bonding holes (not shown) for bonding and connecting are provided.

In this flexible printed wiring board, the NG hole 40 is formed outside the formation area of the conductor pattern 20, and the dummy pattern 30 having a diameter larger than that of the NG hole 40 is formed in the formed area. , And the other conductor pattern 20. Here, in this example, in order to form a plating film on the surface of the conductor pattern 20 by electroplating, in addition to the conductor pattern 20 actually used as an individual flexible printed wiring board,
The wiring pattern 20a for the electrode is formed, and the dummy pattern 30 is the wiring pattern 2 for the electrode.
It is formed in a shape connected to 0a. Further, since the dummy pattern 30 functions as protection of the cutting edge of the tool 70 such as a mark and a punch pin at the drilled portion of the NG hole 40 and does not require the central portion, the portion having a smaller diameter than the NG hole 40 is in the middle. It is formed in a blank ring shape, and the pattern of unnecessary portions is omitted.

When the NG hole 40 is formed in such a flexible printed wiring board, as shown in FIG. 2, the dummy pattern 30 and the base material 10 are punched out by a tool 70 such as a punch pin to form the NG hole 40. The through-hole may be formed. As shown in FIG. 3, the punched NG hole 40 is slightly wound with the dummy pattern 30 on the upper portion thereof, and the wound dummy pattern 30 protects the cutting edge of the tool 70 and the glass cloth. The fluff due to the fibers is pushed down, and the shape is accurately formed.

FIG. 4 shows another example of the flexible printed wiring board according to the invention of claim 1. In this flexible printed wiring board, NG holes 40 are formed in the formation regions of the conductor patterns 20 actually used as individual flexible printed wiring boards. Therefore, the dummy pattern 40 is formed in a shape separated from the conductor patterns 20 so that the conductor patterns 20 actually used as individual flexible wiring boards are not short-circuited. Note that, also in this example, the conductor pattern 20
In addition to the conductor patterns 20 actually used as individual flexible printed wiring boards for forming a plating film on the surface of the electrode by electroplating, wiring patterns 20a for electrodes are formed, and the dummy patterns 30 are formed.
Are formed in a shape connected to the lead-out pattern 20a for this electrode.

Next, FIG. 5 shows an example of a flexible printed wiring board according to the invention of claim 2. In this flexible printed wiring board, NG holes 40 are formed outside the area where the conductor patterns 20 actually used as individual flexible printed wiring boards are formed. Here, in the base material 10, the NG holes 40 are to be drilled at the site where
A primary hole 50 having a larger diameter than the hole 40 is provided,
The dummy pattern 3 is formed so as to cover the primary hole 50.
0 is provided. Here, the primary hole 50 includes a sprocket hole 60, a chip hole (not shown), and a bonding hole (not shown) in the base material 10 by punching or the like.
It is formed together with these through holes when forming such through holes. When the NG hole 40 is formed in such a flexible printed wiring board, as shown in FIG. 6, the dummy pattern 30 is formed on the tool 70 such as a punch pin.
You just have to punch through.

[0022]

As described above in detail, the punch pin is provided by providing the dummy pattern having a diameter larger than that of the NG hole in the portion where the NG hole is formed, as in the flexible printed wiring board according to the present invention. When the NG hole is bored by such a tool, the tool edge can be protected to extend the life of the tool, and the fluff generated by the fibers of the glass cloth can be pushed downward.
Furthermore, the dummy pattern can clearly indicate the site where the NG hole should be formed.

Therefore, according to each of the present invention, it is possible to provide a flexible printed wiring board having a simple structure, in which an NG hole can be formed in an accurate portion with an accurate shape.

[0024] Particularly, according to the invention of claim 2, since the primary hole having a diameter larger than that of the NG hole is formed in the portion of the base material where the NG hole is to be formed, the NG hole is formed. It is not necessary to punch out the base material during installation, and the life of the tool can be further extended.

[Brief description of drawings]

FIG. 1 is a partial plan view showing an example of a flexible printed wiring board according to the invention of claim 1. FIG.

FIG. 2 shows the flexible printed wiring board shown in FIG.
It is a cross-sectional partial front view which shows the state which perforates a G hole.

FIG. 3 is a partial sectional front view showing an NG hole.

FIG. 4 is a partial plan view showing another example of the flexible printed wiring board according to the invention of claim 1.

FIG. 5 is a partial plan view showing another example of the flexible printed wiring board according to the invention of claim 1.

FIG. 6 shows a flexible printed wiring board shown in FIG.
It is a cross-sectional partial front view which shows the state which perforates a G hole.

FIG. 7 is a partial plan view showing a conventional flexible printed wiring board.

FIG. 8 is a partial plan view showing a conventional flexible printed wiring board.

FIG. 9 is a partial cross-sectional front view showing a state in which an NG hole is formed in a conventional flexible printed wiring board.

[Explanation of symbols]

 10 Base Material 20 Conductor Pattern 20a Routing Pattern 30 Dummy Pattern 40 NG Hole 50 Primary Hole 60 Sprocket Hole 70 Tool

Claims (2)

[Claims] 1. A sheet-like base material obtained by impregnating glass cloth with a resin, and a conductor pattern formed on the surface of the base material. An NG hole is formed when a defective product is recognized. The flexible printed wiring board according to claim 1, wherein a dummy pattern having a diameter larger than that of the NG hole is provided in a portion of the surface of the base material where the NG hole is formed. 2. A flexible printed wiring board according to claim 1, wherein the substrate is provided with a primary hole having a diameter larger than that of the NG hole, and a dummy pattern is provided so as to cover the primary hole. .