JPH02183591A - Printed board - Google Patents

Abstract

PURPOSE:To prevent an electric component and an electrode pattern from solder-isolating due to fusion and flowout of solder from a through hole by providing resist at an opening edge of the through hole at the side of the electric component on one side face of an insulating board. CONSTITUTION:The opening edge of a through hole 6 at the side of an electric component 2 one side face of an insulating board 1 is coated with resist 3a. Accordingly, heat is applied to the solder 5 of the electric component 2 previously soldered via the through hole 6 and its inner solder 5' at the time of soldering with the solder 5', and even if it is fusion-adhered, it does not melt and flow out from the through hole 6. Thus, it can prevent the electric component 2 and an electrode pattern 4 from solder-isolating.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a printed circuit board having electrode patterns on both sides of an insulating substrate.

BACKGROUND OF THE INVENTION FIG. 3 shows the structure of a conventional printed circuit board.

Reference numeral 1 denotes an insulating substrate, and electrode patterns 4 and 4' are provided on both sides of the insulating substrate 1. And electrode pattern 4 on both sides
．． An electric component 2.2' is fixed to 4' with solder 6.5'. Further, the electrode patterns 4 and 4' on both sides are electrically connected through a through hole 6 penetrating the insulating substrate 1. Note that 3 and 3' are resists.

Problems to be Solved by the Invention However, in the conventional configuration described above, when soldering the solder 6', the solder 6 of the electrical component 2 soldered first melts and flows downward from the through-hole hole 6, causing electrical Part 2
There was a problem in that the solder of the electrode pattern 4 and the solder of the electrode pattern 4 were separated.

The present invention solves the above-mentioned problems, and aims to prevent solder separation between an electrical component and an electrode pattern due to melting and outflow of solder.

Means for Solving the Problems In order to achieve this object, the printed circuit board of the present invention is such that the opening edges of the through-holes on the electrical component side are coated with a resist on at least one surface of the insulating substrate.

According to the above-mentioned method, the resist provided at the opening edge of the through-hole can prevent solder from flowing out toward the through-hole, thereby preventing solder separation between the electrical component and the electrode pattern. It can be prevented.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a printed circuit board in an embodiment of the present invention. Note that the same parts as in the conventional example are given the same numbers to simplify the explanation.

The feature of this embodiment is that on at least one surface of the insulating substrate 1, at the opening edge of the through-hole hole 6 on the electric component 2 side,
This is because the resist 3a was applied.

That is, when the resist 3a is used as in this embodiment, the resist 3a is provided between the electrode pattern 4 of the electrical component 2 soldered previously and the through-hole hole 6, so that the soldering of the next soldering 6' is performed. During soldering, heat is sometimes applied to the solder 6 of the previously soldered electrical component 2 through the through-hole θ and the solder 6' inside it, and even if it melts, it melts and flows downward from the through-hole 6. There isn't. Therefore, solder separation between the electrical component 2 and the electrode pattern 4 can be prevented. In this embodiment, the resist 3a is provided only on the electrode pattern 4 side, but it may be provided on the electrode pattern 4'.

FIG. 2 shows another embodiment of the present invention, and the feature of this embodiment is a resistor (31L) provided at the opening of the through-hole hole 6.
When soldering the electrical component 2, the solder 6 is held and the soldering of the electrical component 2 is improved by making the part semicircular as shown by 7.

Effects of the Invention As described above, in the present invention, a resist is provided at the opening edge of the through-hole on the electrical component side on at least one surface of the insulating substrate, so when soldering is performed on the rear surface, the solder is removed first. It is possible to prevent the solder of the attached electrical component from melting and flowing out from the through-hole hole, thereby preventing solder separation between the electrical component and the electrode pattern.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a printed circuit board according to an embodiment of the present invention, FIG. 2 is a top view of a second embodiment of the present invention, and FIG. 3 is a cross-sectional view of a conventional printed circuit board. 1... Insulating board, 2.2'... Electrical component, 3.3'. 3 &... Resist, 4.4'... Electrode pattern, 6°6'... Solder, 6...
Through-hole hole, 7...Resist shape. Figure 1 2rl! J Figure 3

Claims (1)

[Claims] An insulating substrate, an electrode pattern provided on both sides of the insulating substrate, a through-hole hole provided through the insulating substrate to connect the electrode patterns on both sides, and an insulating substrate provided in the vicinity of the through-hole hole. A printed circuit board comprising electrical components soldered to electrode pattern portions on both sides of the substrate, and on at least one surface of the insulating substrate, opening edges of the through-holes on the electrical component side are coated with a resist.