JPS5931097A - Method of punching metal base printed circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for punching metal-based printed wiring boards.

With the advancement of electronic devices and electronic components, the effectiveness of printed wiring boards based on metal substrates has begun to be recognized. The production of metal-based printed wiring boards is basically the same as the manufacturing process of conventional resin substrates, but there is a fundamental difference in that the substrate is mostly metal, unlike conventional resin.

As shown in Figure 1, a printed wiring board (6) with gold-plated circuit parts (3) such as contacts and bonded ink terminals.
Take the terminal + terminal (4) on the same circumference, and connect the lead part (5)
It is formed using electrical continuity with the circuit part (3). In the case of a resin substrate (9), there is no problem if the lead parts (5) for establishing electrical continuity are punched out as they are, as shown in Figure 2, but in the case of a metal substrate (t+1), there is no problem when punching Later, it will definitely be electrically connected to the metal substrate +1+.

That is, as shown in Fig. 3, in the case of the metal substrate fi+, there are originally three independent circuit parts (3)
The printed wiring board (6) is 3.
The circuit part (3) of the book is all short-circuited through the metal substrate fi+, which is an electrical conductor, and the circuit becomes meaningless. In the case of metal-based printed wiring boards, short circuits at the edges must be completely avoided for the same reason. Printed wiring board with only regular etching machine (6
), it would be sufficient to design the circuit separately from the external shape at the circuit design stage, but this is not possible with conventional construction methods for the printed wiring board (6) to which electromechanics is applied. In view of this point, the present invention is to create a metal-based printed wiring board that has been fitted by removing the circuit portion (3) of the punched-out portion. However, the gold-plated and ν+ parts do not dissolve in chemicals such as ferric chloride and cupric chloride, which are used to etch copper foil, and dissolution with chemically stable soothing chemicals is not industrially possible. It is possible. or,
Cutting and removing that part with a sharp tool such as a knife or machining may also cause a short circuit between the circuit and the metal substrate because the insulating layer is thin.

The present invention was made in view of the technical background described in the paper, and its purpose is to create a metal paste whose outer shape can be punched out and plated terminals can be separated without shorting circuit parts using a base metal substrate. To provide a method for punching out printed wiring boards.

Hereinafter, the present invention will be explained in detail with reference to the accompanying drawings. In Fig. 4, il+ is a metal substrate such as an aluminum plate or iron plate, (2) is an insulating layer such as epoxy resin, and (io) is a metal foil such as copper foil. The metal foil (1o) of this foil-clad laminate (11) is etched with a ferric chloride solution to form a predetermined circuit portion (3) and a plated terminal (4) on the surface. Both (3) (4
) to form leads 5 (5) to obtain a printed wiring board (6) as shown in FIG. Next, as shown in Fig. 6, print a tsulter resist as a meth resistor (7) in the feudal multi-circuit part 13) where the meth+ is required, the lead part (5) which will be the cutting site, and the meth+ electrode ( 12) to the printed wiring board (6), and as shown in Figure 7, the exposed part of the lead part (6) is covered with tape such as vinyl tape (8) to prevent scratches. Cover the exposed circuit part (3) with nickel and gold electrolyte v+.After this, remove the tape (8) and etch it again with ferric chloride solution. When +51 is dissolved and removed, the 8th
As shown in the figure, the plated terminal (4) and the marked circuit part (
A printed wiring board (6) separated from 3) is obtained. Finally, as shown in FIG. 9, the lead portion (6) was punched out into a predetermined shape so as to pass through the removed portion to obtain a metal paste printed wiring board having a metallurgical circuit. In this way, the metal foil (io) is not cut during punching, so that no short circuit occurs in the circuit portion (3). Sho, Chizu (8)
may be formed by applying a resist that can be removed later.

In the present invention, as described above, the lead portion is exposed from the metal resist and the tape is pasted from above to seal the circuit portion, so if the tape is peeled off after the metal resist, the lead portion can be removed by the error rank. If you punch out the part where the part was removed, there is no risk of the metal foil of the circuit part touching the metal board and causing a short circuit.

This has the advantage of improving quality.

[Brief explanation of the drawing]

Fig. 1 is a partially broken plan view of a conventional example, wJ2 Fig. 3 and Fig. 3 are sectional views of a printed wiring board punched by the conventional method.
FIGS. 4 to 9 are explanatory diagrams showing one embodiment of the method of the present invention. (1)...Metal substrate, (2)...Insulating layer, (3)...
...Circuit part, (4)...Plated terminal, (5)...
Lead part, (6)...Prisit wiring board, (7)...
Metsushi Resist, (8) 19. Chi-j. Agent Patent Attorney Ishi 1) Chief 7 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1゜Figure 6 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] ill An insulating layer is provided on the upper surface of the metal substrate, and a circuit part, plated terminals, and lead parts connecting the two are provided on the insulating layer using metal foil to form a printed wiring board. Apply metal resist to the surface of the wiring board except for the necessary parts and leads, and apply a metal resist tape to the lead parts. A method for punching out a metal-based printed wiring board, characterized in that the lead portion is removed and the printed wiring board is punched out at the location where the lead portion has been removed.