JPS5914917B2 - Manufacturing method of printed wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a printed wiring board using a die stamping method.

The die stamping method is a method for manufacturing printed wiring boards using a cutting die, and conventional methods are roughly divided into a one-step stamping method and a two-step stamping method.

In the one-step stamping method, as shown in Figure 1, the inner moat 1
1 and the outer moat part 12 are used, and the substrate 2 is
A conductive foil 3 is stamped with a conductive foil 3 disposed on top with a pasted layer 4 interposed therebetween. In this case, the blade die 1 is heated to a temperature slightly higher than the temperature at which the adhesive layer 4 flows (suddenly softens). The two-step stamping method is shown in Figure 2a.
As shown in FIG. 2, first, the part of the conductor foil 3 placed on the substrate 2 via the adhesive layer 4, which will be left as a conductor pattern later, is pressed with a flat mold 5 to partially bond the adhesive sardine 4. The conductor foil 3 in this part is fixed by flowing, and then, as shown in Fig. 2b, a low-temperature blade mold 1 (in this case, there may or may not be 5 steps in the inner moat part and the outer moat part) is used. ) is used for stamping. In both of the above two methods, two methods can be applied: one in which the adhesive layer is formed in advance on the conductor foil 3 side, and one in which it is formed in advance on the substrate 2 side.

Usually, from the viewpoint of work efficiency of 10, the adhesive layer 4 is formed in advance on the conductor foil 3 side, and the printed wiring board is often manufactured by the above-mentioned one-step stamping method. However, in these conventional die stamping methods, the hardness of the substrate is
If the hardness is 15, which is the same as or higher than the hardness of the blade (for example, when a glass epoxy/substrate is used as the substrate), it cannot be applied.

Further, there are drawbacks such as difficulty in manufacturing three-dimensional printed wiring boards. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a printed wiring board using the die stamping method, which improves the above-mentioned drawbacks.

An embodiment of the present invention will be described below.

First, as shown in FIG. 3, a plastic film 6 such as polypropylene film, which has relatively good heat resistance and is inexpensive, is used as a substrate, and a conductor foil 7 made of copper or the like is placed on this film 6 using a thermoplastic resin such as polyester. The adhesive layer 8 is used for adhesion. At this time, the surface of the conductive foil T is not rough but rough. Then, stamping is performed using the blade die 9. At this time, the blade 30 type 9 is heated to a temperature slightly higher than the temperature at which the contact layer 8 of the thermoplastic resin flows. After this stamping, the parts other than the conductor pattern 71 are peeled off manually or automatically by a machine, and the conductor butter 35 T is bonded with an adhesive layer 81 as shown in FIG.
form i. Next, the substrate (including film-like ones) 2
0, a thermosetting resin such as phenol is applied to form an adhesive layer 30, and this adhesive layer 30 and the conductive pattern 71 formed on the film 6 are made to face each other. Then, the substrate 20 and the film 6 are overlapped.

Then, the heated pressing plate 40 presses the film 6 toward the substrate 20. Then, thermoplastic adhesive Qiake 81
is softened and the thermosetting adhesive layer 31 is hardened, so that the conductor pattern 71 is bonded by the adhesive layer 30. After the adhesive layer 30 has hardened in this way, if the film 6 is peeled off, a conductive pattern 71 is formed on the substrate 20 as shown in FIG. can get. At this time, the surface of the conductor pattern 71 in contact with the adhesive layer 30 is not smooth and rough as described above, so this surface is in contact with the adhesive layer 30.
0 easily and firmly. In this way, the printed wiring board is manufactured by transferring the conductor pattern 71 formed on the film 6 by the die stamping method onto the substrate board 20.

Therefore, according to this manufacturing method, the conductive pattern rl can be formed even when the substrate 20 is harder than the blade 9 (when the substrate 20 is made of glass epoxy, poron, etc.).

Further, since the stamping process and the peeling process are performed on the film 6, transportation becomes easy. Furthermore, since this is a so-called transfer method, the conductive patterns 71, 71, 71 are three-dimensionally formed on the substrate 20 by using a flexible film 6 as shown in FIG. 7 and FIG. It can also be formed.

[Brief explanation of the drawing]

Figure 1 and Figures 2A and b are sectional views for explaining the conventional manufacturing method, Figures 3, 4, 5 and 6 are manufacturing methods according to an embodiment of the present invention. FIGS. 7 and 8 are cross-sectional views showing each step of the method, and FIGS. 7 and 8 are cross-sectional views showing each step of a modified example. 1, 9...Blade type, 2,20...Substrate,
3, 7... Conductor foil, 71... Conductor pattern, 4... Adhesive layer, 5... Flat type,
8...Thermoplastic adhesive layer, 30...Thermosetting adhesive layer, 40... Press plate.

Claims (1)

[Claims] 1. Form a conductive pattern on a first substrate by sandwiching a first adhesive layer using a die stamping method, and then make the conductive pattern face the second adhesive layer of a second substrate. While pressing the first substrate and the second substrate together, the first adhesive layer is softened and the second adhesive layer is hardened, and then the first substrate is peeled off. A method for manufacturing a printed wiring board, characterized by: