JPS60249387A - Method of forming wiring pattern of 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 forming a wiring pattern on a printed wiring board used for mounting electronic components and mutual wiring between these electronic components. A common method is to obtain the pattern by etching the board, but this method requires the creation of a mask (original image) for each printed wiring board. As a wiring pattern formation method that does not require mask creation,
There is a method of wiring by applying a conductive fluid material directly onto the board. The conductive fluid material is a fluid as it is, and once drawing is completed, it needs to be fired at the firing temperature of the fluid material. In addition, conductive fluid materials are naturally electrical conductors, and in order to cross in an insulating state, after drawing with conductive fluid material, firing 1~, then apply insulating material to the area where you want to cross, and then apply conductive fluid material It requires multiple drawing processes, which has the disadvantage of increasing man-hours. Further, since the drawn conductive fluid material is a conductor, it is necessary to newly apply an insulation resist from the viewpoint of insulation between wiring patterns.

The present invention solves the above-mentioned conventional drawbacks by discharging a conductive fluid material using a fluid discharge machine according to pattern wiring data and simultaneously discharging an insulating fluid material onto the surface of the conductive fluid material to perform wiring. The purpose of this method is to provide a wiring pattern forming method that eliminates the need for wiring patterns. According to this method, insulation crossing of wiring can be performed in - times of drawing.
In addition, since an insulating fluid material is discharged onto the surface of the conductive fluid material while discharging the conductive fluid material to cover the conductive fluid material, the insulation effect between the wiring patterns is also exhibited, and there is no need to apply an insulation resist to the wiring patterns again. This also eliminates the need for high quality printed wiring boards.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a conventional wiring pattern forming method for a printed wiring board, and FIGS. 2(a) and 2(b) are cross-sectional views taken along line A-A in FIG. This figure shows each ridge side of the tip nozzle shape of the fluid ejector. In this conventional example, a printed wiring board 1 has a plurality of conductor pads 3a.
, 3b are provided, and in order to connect these conductor pads, a conductive fluid material 4 is discharged onto the substrate 1 from the nozzle tip 2a of the fluid discharger 2 according to pattern wiring data and wired. The conductive fluid material 4 is a fluid and is fired after drawing is completed. Furthermore, since the conductive fluid material 4 is a conductor, in order to cross the wiring, it is drawn with the conductive fluid material 4 and then fired, and then an insulating material (not shown) is used.
This method requires multiple processes, such as applying it to the area where it is desired to intersect, and then drawing the applied area again with a conductive fluid material, which has the drawback of increasing the number of man-hours. Unfortunately, since the drawn conductive fluid material is a conductor, it is necessary to apply an insulating resist 5 (only a portion is shown) on the surface of the wiring patterns in order to insulate the plurality of wiring patterns from each other. In addition, Fig. 2 (a), (b
) is a cross-sectional example of the nozzle tip 2a of the fluid ejector 2,
The example in Fig. 2(a) is a circular nozzle, and the viscosity of the fluid material is
The discharge hole 6a is provided depending on the viscosity of the fluid material and the like.

Further, FIG. 2(b) shows a square nozzle having a discharge hole 6b similar to the circular nozzle. As described above, the conventional method of drawing using conductive fluid materials has the drawback of requiring multiple processing steps and increasing the number of man-hours.Also, since conductive fluid materials are naturally conductors, insulating resist is required as post-processing. It had drawbacks such as: The present invention eliminates these drawbacks and provides an excellent printed wiring board.

FIG. 3 is a perspective view showing an example of a method for forming a wiring pattern on a printed wiring board according to the present invention. Referring to the same figure, a printed circuit board 0 is provided with a plurality of conductive pads 15, and a conductive fluid material 12 is applied to a pattern 7 to interconnect the conductive pads 15. ~Therefore, the fluid is discharged from the nozzle tip 11a of the fluid discharge gAll.

At this time, the insulating fluid material 13 is simultaneously discharged from the adjacent nozzle tip 11b, and the surface of the conductive fluid material 12 is covered and wired with the insulating fluid material 13. Since the conductive fluid material 12 is thus overcoated with the insulating fluid material 13, it is possible to cross the wires during drawing. FIG. 4 shows this.

Note that FIG. 4 is a sectional view taken along the line BB in FIG. 3. Since the lower conductive fluid material 12a is overcoated with the insulating fluid material 13a on the outside, the intersecting upper conductive fluid material 12b is insulated with the insulating fluid material 13a and the wiring pattern can be connected without shorting. Crossover is possible. Furthermore, since the conductive fluid material 12b on the upper side of the intersection is similarly overcoated with the insulating fluid material 13 during drawing, an insulating resist or the like for insulation between the plurality of wiring patterns is no longer necessary. After the wiring is completed in this way, it is fired and the printed wiring board is completed.

FIG. 5 is a cross-sectional view of the nozzle tip 11a of the fluid ejector 11 that makes the present invention possible, taken along line CC in FIG. As shown in the figure, the discharge hole is divided into 14a and 14b, and the insulating fluid material is discharged from the discharge hole 14a.
A conductive fluid material is discharged from 4b. The discharge hole 1
The sizes of 4a and 14b are set depending on the discharge amount, viscosity, etc. of the insulating fluid material and the conductive fluid material, respectively. It should be noted that the shape shown in FIG. 5 is just an example, and it goes without saying that the shape may be square or other shapes instead of circular.

As described above, in the method for forming a wiring pattern on a printed wiring board according to the present invention, wiring can be crossed during drawing, and
Since the conductor is overcoated with an insulator and is not exposed, an excellent printed wiring board can be provided that does not require additional insulation resist. Note that in some cases, the fluid discharge machine 11
It goes without saying that it is also possible to discharge only the insulating fluid material or, conversely, only the conductive fluid material from the discharge hole by controlling the discharge hole.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing a conventional wiring pattern forming method for a printed wiring board, and Figures 2 (a) and (b) are examples of the shape of the tip nozzle of a fluid ejector shown in cross section A-A in Figure 1. 3 is a perspective view showing an example of a wiring pattern forming method for a printed wiring board according to the invention, FIG. 4 is a sectional view taken along line B-B in FIG. 3, and FIG. FIG. 4 is a sectional view of the nozzle tip taken along line CC in FIG. 3; 1.10...Printed wiring board, 2.11...Fluid discharge machine, 3a, 3b, 15-conductor pad, 4.12...Conductive fluid material, 13...Insulating fluid material, 6a , 6b, 14a, 14b - discharge hole. Agent Patent Attorney Rikichi Someyo Figure 2 (0) (b)

Claims (1)

[Claims] In a method for forming a wiring pattern on a printed wiring board, wiring is performed by discharging a conductive fluid material using a fluid discharge machine according to pattern wiring data and simultaneously discharging an insulating fluid material onto the surface of the conductive fluid material, and then printing. A method for forming a wiring pattern on a printed wiring board, the method comprising firing the wiring board.