JPS64837B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for connecting wiring on a flexible substrate, in which a through hole is formed in the flexible substrate and printed wiring on both sides of the substrate is electrically connected. be.

Conventionally, as a method for electrically connecting printed wiring formed on both sides of a flexible substrate, for example, the steps are shown in Fig. 1 A, B, and C.
A through hole 2 is formed in advance in a required part of the substrate 1, and an insertion rod 3 is inserted into the through hole 2, and the tip is coated with conductive paste (Ag, Ag-C, C paste, etc.). A method of electrically connecting the printed wiring on both sides of the board as shown in FIG.
As shown in the figure, a conductive paste is printed and applied 7 to the pre-formed through holes 2 from one side of the substrate 1, and then a conductive paste is printed and applied 8 to the through holes 2 from the opposite side.
As shown in Fig. 3, Cu plating 9 is applied to the through hole 2, and then Au plating 1 is applied to prevent oxidation
A connection method called the so-called copper through-hole method has been proposed.

However, all of these conventional connection methods involve forming through-holes in the substrate in advance and connecting them in subsequent processing, which has the drawback of requiring a large number of steps and lengthening the working time. Since a mold for forming the through holes is also required, the equipment is complicated and expensive.

Furthermore, the method shown in Fig. 2 has the disadvantage that it is not possible to apply the paste continuously using the printing method because the paste passes through the through holes and oozes onto the lower printing stage during printing.
Furthermore, since the method shown in FIG. 3 is performed by plating, the number of steps increases significantly, and furthermore, since the Au plating for oxidation prevention is expensive, an increase in cost is unavoidable.

In view of the drawbacks of such conventional methods, the present invention
The present invention provides a method for connecting printed wiring on a flexible substrate, in which a through hole is formed in the substrate and printed wiring on both sides of the substrate is electrically connected at the same time.

Hereinafter, the connection method according to the present invention will be explained based on the drawings. FIG. 4 shows a first embodiment, in which a conductive paste 11 is first applied on a printed wiring pattern 5 formed on one side of a substrate 1, as shown in FIG. Next, as shown in FIG. 2B, the tip of the punching pin 3' that penetrated the substrate 1 enters the conductive paste tank 12, and is pulled out with the conductive paste attached to the tip. According to this method, both the applied conductive paste 11 and the paste layer 12 can reliably connect the two printed wirings.

In FIG. 5, the connection is made using the paste in the conductive paste tank 12. A perforating pin 3' is pushed down from above the printed wiring pattern 5 to penetrate the board 1, and the tip of the pin that has penetrated is inserted into the paste tank 12. After applying the conductive paste, the pin is pulled out again. In this method, when the pin is pulled out, the paste at the tip of the pin adheres to the portion of the through hole 2, and the printed wiring on both sides of the board is electrically connected as shown in FIG.

In this way, through holes can be formed in the flexible substrate and printed wiring on both sides of the substrate can be electrically connected at the same time.

It is preferable that the perforation pin 3' be thin like a grommets needle and have a groove formed at its tip as shown in FIGS. 6A, 6B and 6C to increase the amount of conductive paste deposited.

As explained in detail above, according to the connection method for a flexible substrate according to the present invention, after pressing down a perforation rod against the substrate to form a through hole in the substrate, the perforation rod to make the conductive paste attached to the tip of the punching rod adhere to the hole, thereby electrically connecting the wiring on both sides of the board.Then, move the punching rod up and down toward the board. By simply doing this, you can perform two processes at once: forming a through hole on the board and connecting the wiring on both sides of the board. The number of steps and connection work time can be reduced, and the electrical connection of double-sided wiring can be ensured using the conductive paste.

[Brief explanation of the drawing]

1 and 2, and FIG. 3 are diagrams showing the conventional method. FIG. 4, A, B, and C are diagrams showing the first embodiment of the present invention. A, B, and C are views showing a second embodiment of the present invention, and FIG. 6A, B, and C are views showing an example of a punching pin. 1 is the substrate, 2 is the through hole, 4, 1
2 is a conductive paste tank, 3' is a perforation pin, 5, 6
is printed wiring, and 11 is conductive paste.

Claims (1)

[Claims] 1. A process of applying conductive paste on a wiring pattern formed on one side of a board, and pressing down a perforating rod from above the paste before the applied paste hardens. A process of forming a through hole, and a process of attaching a conductive paste to the tip of the drilling rod that penetrates the substrate when drilling the through hole in the substrate with the drilling rod. and,
A flexible board characterized by comprising the step of: pulling out the perforation rod to which the conductive paste is attached from the board, and adhering the paste to the drilled through hole to electrically connect the wiring on both sides of the board. How to connect the wiring. 2. A step of pressing down a drilling rod from above the wiring pattern on one side of the board to form a through hole in the board, and a step of drilling a through hole in the board with the drilling rod. , a step of attaching a conductive paste to the tip of the punching rod that penetrates the substrate;
A flexible board comprising the step of attaching the paste to the drilled hole by pulling out the perforation rod to which the conductive paste is attached from the board, thereby electrically connecting the wiring on both sides of the board. How to connect the wiring.