JPH0352234B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a circuit board.

Recently, circuit boards using conductive paint pattern printing have been proposed. This method has the advantage of being able to form wiring patterns simply by printing, requiring no equipment required for photoetching or waste liquid treatment, and being able to be manufactured in a short time. However, carbon-based conductive paints are cheap but have high resistance and cannot be used, while silver-based paints have low resistance but are too expensive to be put to practical use.

An embodiment of the present invention will be described below based on the drawings. 1 and 2, on the entire surface of an insulating substrate 1, a conductive layer 3 of Al, Cu, etc., which is subdivided by narrow gaps 2 and insulated from each other, is formed to constitute a base substrate. .

A conductive paint is printed on this base substrate to form a wiring pattern 4 as shown in FIG. This conductive paint may be an inexpensive one mixed with carbon powder, and even if its resistance is high, the resistance of the conductive layer 3 is low, so the resistance of the wiring pattern 4 is low, and it is sufficiently useful for practical use.

Further, by printing a conductive paint and placing circuit elements and the like before it hardens, soldering becomes unnecessary. Furthermore, since almost the entire surface is electrically conductive, it has good heat dissipation characteristics and can reduce thermal damage to integrated circuits and the like.

When a conductive paint containing carbon powder mixed with a heat-sealing resin such as a thermoplastic resin or an unreacted thermosetting resin is used, circuit elements and the like can be fixed by heat-sealing. Furthermore, when a rubber-based resin is used, conduction can be achieved by pressure contact.

As described above, according to the present invention, a conductive layer is formed on the surface of a base substrate, which is divided into smaller pieces smaller than the minimum width of a wiring pattern formed by printing a conductive paint and insulated from each other. Wiring patterns can be easily formed by simply printing the adhesive paint.
The manufacturing process can be simplified. Moreover, the resistance can be lowered by using carbon-based conductive paint, which is inexpensive and highly reliable. Furthermore, since the entire structure is electrically conductive, it has good heat dissipation characteristics and can reduce thermal damage to the circuit.

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of the present invention, Fig. 2 is an enlarged front view showing a part of Fig. 1, and Fig. 3 is a front view showing a wiring pattern formed in Fig. 1. It is a diagram. 1... Insulating substrate, 2... Gap, 3... Conductive layer.

Claims (1)

[Claims] 1 A conductive layer is formed on the surface of the conductive layer, which is subdivided by narrow gaps and insulated from each other, and a wiring pattern is formed on the conductive layer by printing conductive paint, and the conductive layer is An electric circuit board characterized in that the layer is subdivided into smaller widths than the minimum width of the wiring pattern.