JPS60140788A - Method of forming circuit by pad printing - 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 of forming a circuit by pad printing.

A screen printing method is conventionally known as a means for forming a circuit pattern on a substrate.

Since this screen printing method can only print on flat surfaces, it is impossible to print on substrates having irregularly curved surfaces such as uneven surfaces. Therefore, when printing a circuit pattern on the end surface of a board, as shown in FIG.
First, the circuit pattern 3 is printed on one plane 2 of the substrate 1, and after drying, the circuit pattern 4 is separately printed only on the edge surface and dried, as shown in FIG. 2. It is necessary to repeat the printing process several times. there were.

Japanese Patent Laid-Open No. 57-259 was developed as a technology to eliminate such complicated processes and print on uneven surfaces and edges in one process.
There are techniques published in No. 5 and Japanese Patent Publication No. 55-16388. However, these techniques require a film (transfer paper) to hold the printed circuit pattern layer, and
This circuit pattern is printed on a film (
Generally, the circuit pattern is printed on transfer paper (transfer paper), so in order to vary the thickness of the circuit pattern in any part of the pattern, the parts to be thickly printed must be printed separately by changing the plate-making and printing conditions and multiple printing. It is necessary and complicated.

By the way, if it is possible to easily vary the thickness of a circuit pattern at any part of the pattern, the resistance value can be changed when printing resistive elements, and the demand for thicker soldering parts when printing conductive elements can be met. It is beneficial in that it is satisfying.

Therefore, an object of the present invention is to provide a circuit forming method using pad printing, which allows circuit patterns to be printed on uneven surfaces and end surfaces in a simple process, and in which the thickness of the pattern can be varied at any desired location. It is about providing.

The configuration of the present invention will be described below with reference to one embodiment.

The circuit pattern of the substrate according to the present invention is implemented through each process described below.

1 Circuit pattern engraving step (see Figure 3) Plate making 10,
A circuit pattern 11 corresponding to a desired circuit pattern is carved. In this example, for the sake of explanation, the circuit pattern is made up of simple cross-shaped grooves, but in reality, a complex circuit configuration can be used. Here, if it is necessary to partially change the thickness of the finally completed circuit pattern, the depth of the circuit pattern 11 may be set to a desired thickness at a desired portion.

2. Imprinting process (see Figure 4) Paste 1 is applied to the surface of the plate 10 produced in the previous process.
The paste 12 is imprinted onto the circuit pattern 11 by sliding a spatula 13 or a brush made of an elastic material with a paste 2 stuck thereon.

The paste 12 is prepared according to the function of the circuit pattern to be manufactured.
A material having characteristics such as a conductor, a resistor, and a resist is appropriately selected and used.

3. Transfer adhesion process (see Figures 5 and 6) Press the tip +4a of the elastic pad 14 against the area where the paste [2] has been imprinted in the previous process.

This tip portion 14α has a rounded and convex shape, and has a surface that is sufficiently wider than the size of the circuit pattern 11 filled with the paste 12.

As the elastic band, for example, silicone resin, gelatin, etc. are used. In addition, the material is not necessarily limited to the above materials as long as it has elasticity and has strong drug properties.

By pressing in this manner, the paste] 2 is adhered to the tip portion 14a. Then, when this is pulled up from above the plate making 10, as shown in FIG. 6, the tip portion 14a, J:
The paste 12' in the form of a circuit pattern is transferred to
Attach - come.

4 Printing process (see Figures 7 and 8) The tip 14a of the elastic pad 14 according to the above process is attached to a rectangular parallelepiped substrate 15 as shown in Figure 7, whose surface is coated with alumina, wax, etc. Press.

In this case, since the elastic pad 14 is elastically deformed, the paste 12' moves together with the elastic pad to the end surface 5a of the substrate 15. Therefore, as shown in FIG. 8, transfer and adhesion of the paste 12 to the end face is realized by suppressing - times. In this case, if the thickness of the desired circuit pattern is partially different, the paste thus formed will be deposited on the substrate 15. Further, even if the substrate is not a rectangular parallelepiped but has an arbitrary shape having an uneven surface, the paste is adhered to the substrate according to the uneven surface by the action of the elastic pad.

The paste 12 thus deposited on the substrate 15
5, it is solidified and completed as a circuit board through a drying process and a firing process.

In FIG. 9, reference numeral 16 indicates a cell substrate completed through the above steps. Reference numeral 17 in the figure indicates a terminal portion electrically connected to the circuit pattern. An overcoat 18 is formed on the upper half of the circuit board 16 over the end face, and it goes without saying that the method according to the present invention can also be applied to the formation of such an overcoat 18. .

The cell substrate] 6 is placed on a base substrate 19 shown in FIG. 10, and is connected to a wiring conductor 21 through a connecting conductor 20.

As described above, the present invention employs a method of printing by pressing a circuit pattern-shaped paste attached to an elastic pad onto a substrate, so three-dimensional patterning is possible. Furthermore, it is possible to create multiple layers by changing the depth of the grooves on the plate, changing the viscosity of the paste, or repeating printing multiple times, making it easy to control the printing film thickness. .

Additionally, since the elastic band is soft, it can also be combined with screen printing as long as the previously formed circuit pattern is dry.

In the method using an elastic pad as in the embodiment described above, it is possible to form an etched pattern on a board including a curved surface as well as a printed circuit board.

Similarly, when forming an etching pattern, the substrate is an insulator whose surface is coated with a conductor layer. Then, using a resist as a paste, a circuit pattern is printed on the substrate using the resist paste using an elastic pad. Next, after a drying process, an etching process is performed to remove the conductor parts other than the parts to which the resist is attached, leaving only the resist parts. Further, by removing this resist, a substrate on which a desired circuit pattern is formed is obtained.

[Brief explanation of the drawing]

1 and 2 are perspective views of a board on which a circuit is formed according to the prior art, FIG. 3 is a perspective view of a plate making process, FIG. 4 is a perspective view of a plate making process and a spatula explaining the imprinting process, and FIG. Figure 6 is a perspective view of the plate making and elastic pads explaining the transfer and adhesion process;
Fig. 7 is a perspective view of the board before printing, Fig. 8 is a perspective view of the board after printing, Fig. 9 is a perspective view of the cell board, and Fig. 10 is a perspective view of the cell board assembled on the base board. It is a diagram. ]0 ・Plate making, 12, 12... Paste, 14 Elastic band, 15 - Substrate. 4K

Claims (1)

[Claims] an imprinting process in which paste is imprinted on a plate with a circuit pattern engraved thereon; a transfer/adhesion process in which an elastic band is pressed against the imprinted paste to transfer and adhere the paste to the elastic band; and an elastic pad to which the paste is adhered. A printing process in which the paste is printed on the board by pressing it onto the board,
A method for forming a circuit by pad printing, which includes a drying and firing step of drying and firing the printed paste.