JPS6265496A - Manufacturing 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] [Industrial application field] The present invention relates to a method of manufacturing a printed wiring board.

[Prior Art] Conventionally, as a method for connecting circuit patterns formed on one or both sides of an insulating substrate, a conductive hole that penetrates both sides is provided at the center of a land in a circuit pattern on one or both sides, and this conductive hole A known method is described in Japanese Patent Publication No. Sho 56-15158 by filling a conductive material therein to maintain continuity through the conductive material.

[Problems to be Solved by the Invention] However, according to the method disclosed in Japanese Patent Publication No. 56-15158, land portions 4 are formed on the circuit pattern surface of the insulating substrate 3 on which the pattern 1.2 is formed on one or both sides. After sinking the insulating coatings 6 and 7 of the solder resist, leaving the surrounding areas where 5 and double-sided conductive holes are formed, conductive holes 8 are drilled.
A conductive material 9 made of conductive paint is formed in the conductive hole 8 by L or punching process, and as shown in FIG.
, and connect the circuit patterns 1.2 on both sides.

However, the hole 8 is drilled by drilling or punching after the solder resist insulating coating 7 is provided, so there is a drawback that burrs are formed around the periphery of the hole 8. , such a processing oil was required and an extra number had to be multiplied by one.

Therefore, the present invention has been made in response to the problems in the conventional printed wiring board manufacturing method, and aims to provide a manufacturing method that can perform the drilling process of the conductive holes without causing the formation of paris. It is something to do.

[Step F for Solving Problems] The present invention involves forming a wiring pattern on at least one side of an insulating plate, then drilling a conductive hole, and applying a resist to the wiring pattern surface except for the periphery of the conductive hole. coated with
Further, the conductive hole may be manufactured by filling a conductive material, or the conductive hole may be punched in a copper clad laminate with copper foil pasted on at least one side of the insulating plate, and then the wiring may be wired using the copper foil pasted on the insulating plate. A method for producing a printed wiring board, which comprises forming a pattern, covering the wiring pattern with a resist except for the periphery of the conductive hole, and further filling the conductive hole with a conductive material. be.

[Function] Book 9: lJI is a printed wiring board manufacturing method in which wiring patterns formed on one or both sides of an insulating board are connected via a conductive material filled in a conductive hole. By drilling the conductive holes prior to the process of coating the resist with a resist, gaps caused by the thickness of the resist coating are eliminated, making the holes easy to form without causing flakes, etc. The holes are used for alignment.

[Example] Hereinafter, an example of the method for manufacturing the present ffi Ill printed wiring board will be described with reference to the drawings.

(First Embodiment) FIGS. 1a to 1f are process diagrams showing a first embodiment of the method for manufacturing a printed wiring board of the present invention.

Reference numeral 20 denotes a copper-clad laminate in which a copper foil 22 is stretched on one side of an insulating plate 21.
Form a desired wiring pattern 23 on one side of the wiring pattern 23 (see FIG. 1) 6. Then, as shown in FIG. .

Furthermore, after drilling the conductive holes 25, the surface of the wiring pattern 23 is coated with a resist coating 27 by resist printing, except for the peripheral area 26 of the conductive holes 25 (:
(See Figure 51 d).

Thereafter, as shown in FIG. 1e, a conductive material 28 such as conductive paint is filled into the through hole 25, and the conductive material 28 exposed on both sides of the insulating plate 21 is filled, as shown in FIG.
A printed wiring board 30 is manufactured by covering I28a with an overcoat 29.

(Second Embodiment) FIGS. 2a to 2e are process diagrams showing a second embodiment of the method for manufacturing a printed wiring board of the present invention.

Therefore, in this embodiment, compared to the first embodiment, as shown in FIG. 2a, the copper foil 22 of the copper-clad laminate 20 is
Therefore, prior to the step of forming the wiring pattern 23, the conducting hole 25 is punched.

Thereafter, as shown in FIG. 2, a required wiring pattern 23 is formed using the copper foil 22 after the conductive holes 25 have been punched, and a subsequent coating process with a resist film 27 is performed to form the conductive holes 2.
5, filling process of conductive material 28, and further exposing portion 28a.
The coating process for the overcoat 29 is as shown in JS2 Figures c, d and e, and is carried out by the same process as in the first embodiment shown in Figures 1 d-f.

In addition, as for FIGS. 2c, d, and e, the first embodiment is carried out by the same steps, and the same components in each process diagram are designated by the same numbers and the explanation thereof will be omitted.

Further, the method of forming the wiring pattern 23 and the method of drilling the conductive hole 25 in the 1.2 embodiment, and furthermore,
and overcoating method, and the conductive material 2 into the conductive hole 25.
The filling method No. 8 can be carried out by a well-known method and is not limited to a specific method.

Furthermore, in Example 1.2, the case where the wiring pattern 23 is formed on one side of the insulating plate 21 has been described.
The same method can be applied to the case where wiring patterns are formed on both sides.

[Effects of the Invention] According to the method for manufacturing a printed wiring board of the present invention, the step of drilling conductive holes to be filled with a conductive material is performed prior to the step of forming a resist coat for a wiring pattern.
The conductive hole can be manufactured while preventing the occurrence of burrs during processing, and the conductive hole can be filled with a conductive material smoothly and accurately, making it possible to manufacture a through hole of a constant shape.

In addition, the drilling process allows for accurate alignment with the holes, allows for early detection of defects, and has the advantage of reducing loss of charge.

[Brief explanation of drawings]

Figures 1a-f are process diagrams showing the first embodiment of the method for manufacturing the printed wiring board of the present invention, Figures 2a-e are process diagrams showing the second embodiment, and Figures 3a, b is a sectional view showing a conventional manufacturing method. 20...Copper-clad laminate 21...Insulating plate 22...Copper foil 23...Wiring pattern 24...Land 25...Conducting hole 26...Periphery of the conducting hole 27... Resist film 28... Conductive material 29... Overcoat 30... Printed wiring board Fig. 2

Claims (2)

[Claims] (1) After forming a wiring pattern on at least one side of an insulating plate, a conductive hole is punched, the surface of the wiring pattern is covered with a resist except for the periphery of the conductive hole, and the conductive hole is filled with a conductive material. A method for manufacturing a printed wiring board, characterized by manufacturing it by: (2) After drilling a conductive hole in a copper-clad laminate with copper foil pasted on at least one side of an insulating plate, a wiring pattern is formed using the copper foil pasted on the insulating plate, and the wiring pattern surface is connected to the conductive hole. 1. A method of manufacturing a printed wiring board, which comprises covering the printed wiring board except for the periphery with a resist, and further filling the conductive hole with a conductive material.