JPS60262637A - Metallic-base laminated 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 [Technical Field] The present invention relates to a metal base laminate in which grooves formed at predetermined locations of a metal plate are filled with a low thermally conductive insulator.

[Background technology 1] In a metal base laminate A' formed by pasting a gold rA foil 3 on a conventional metal plate 1 via an insulating layer 2, a heat generating component is mounted as a metal base printed wiring board B'. In this case, the heat from the heat-generating component is transmitted to the surroundings through the metal plate 1, which adversely affects other mounted components that are sensitive to heat. In addition, when the metal plate 1 is cut to a predetermined size or a hole for a through hole is processed, the insulating layer 2 is cut or implanted by the sag 6 formed in the metal plate 1, as shown in FIGS. 8 and 9. The metal base printed wiring board B' is peeled off and a gap 8 is formed between the metal plate 1 and the metal base printed wiring board B'.
When used as such, it was unreliable in terms of rust prevention, moisture resistance, and water resistance.

[Objective of the Invention 1 The present invention has been made in view of the above circumstances, and its object is to fill the grooves formed at predetermined locations of a metal plate with a low heat conductive insulator to replace heat-generating components. Even when mounted, there is no adverse effect on other mounted components that are sensitive to heat, and even when cutting or drilling is performed, the insulating layer will not peel off due to the formation of holes, making it rust-proof. The object of the present invention is to provide a metal-based laminate that can ensure moisture resistance and water resistance and can provide a highly reliable metal-based printed wiring board.

[Disclosure of the Invention] The metal base laminate of the present invention is a metal base laminate A formed by pasting a metal foil 3 on a metal plate 1 via an insulating layer 2.
A groove 5 is formed in a portion of the metal plate 1 corresponding to the periphery of the location 4a where the heat generating component 4 is scheduled to be mounted, and the groove 5 is filled with a low heat conductive insulator 9. With this configuration, the above object can be achieved.

That is, heat conduction in the groove portion 5 can be reduced.

The present invention will be described in detail below based on embodiments shown in the accompanying drawings. The metal plate 1 in the present invention can be any copper plate, aluminum plate, brass plate, iron plate, stainless steel plate, nickel plate, silicon steel plate, etc., and usually has a thickness of 0.5 to 2.5 mm. A material in the range of O+nm is used. A groove portion 5 is provided on one side of this metal plate 1. The groove 2 has a rectangular planar shape as shown in FIG. 1, and a triangular cross-sectional shape as shown in FIG. Note that the planar shape of the groove portion 5 may be in the shape of a single character as shown in FIG. 3, or may have any shape as long as it corresponds to the peripheral portion of the location 4a where the heat generating component 4 is scheduled to be mounted. Further, the cross-sectional shape of the groove portion 2 may be either a rectangular shape (FIG. 5(a)) or a semicircular shape (FIG. 5(11)) as shown in FIG. It may be formed on both sides of the metal plate 1.

After filling the grooves 5 of the metal plate 1 with a low thermal conductive insulator 9, metal foils 4 are pasted on both sides with an insulating layer 3 interposed therebetween. +nX1 +n metal base laminate A is formed. Low thermal conductivity insulators have a thermal conductivity of I x 10”
'cat/ ℃・Cm・5ecl, J, refers to the following, for example, a compound containing 3 parts by weight of fucyanoamide and 30 parts by weight of glass balloon per 00 parts by weight of epoxy resin (with a thermal conductivity of 1. -'cat/'C-
cm-sec). As the insulating layer 2, a base material such as glass cloth, asbeth l paper, or synthetic fiber cloth impregnated with a thermosetting resin such as epoxy resin, 7-ether resin, or unsaturated polyester resin, or a thermoplastic resin is used. It ends with that. As the metal foil 3, copper foil, aluminum foil, brass foil, iron foil, stainless steel foil, nickel foil, silicon steel foil, etc. can be used. This metal Yi3 may be attached only to one side of the metal plate 1 with the insulating layer 2 interposed therebetween. In addition, this metal base laminate A is arranged between heating platens, insulating layer 2 is arranged on both sides of metal plate 1, and metal foil 3 is arranged on both sides of insulating wi2. It can be obtained by lamination molding under certain conditions.

In the metal base laminate A configured in this way, if the heat generating component 4 is mounted in the heat generating component mounting location 4a when used as a metal base printed wiring board as is, the low thermal conductivity insulator 9 will also exist in the groove portion 5. Therefore, this groove 5
The thermal conductivity of the metal plate 1 decreases, and other components mounted elsewhere are not adversely affected by the heat. Further, as shown in FIG. 6, cutting or perforation was performed from the groove 5 side of the metal plate 1 along the groove 5 by pressing with a mold or cutting with a shear to form a metal base printed wiring board B. In this case, since the low thermal conductivity insulator 9 is present in the groove 5 of the metal plate 1, even if a drop 6 is formed on the bottom wall of the groove 5 of the metal plate 1 due to processing, the low thermal conductivity insulator 9 is present in the groove 5 of the metal plate 1. 9 and the metal plate 1 are only peeled off, but the insulating layer 2 under the formed circuit 7 is not peeled off. For example, in the case where the circuit 7 is formed at a distance L=2+nm from the processed end surface, when salt water (5% by weight) is sprayed for 96 hours, the circuit 7 of the embodiment of the present invention shown in FIG. = L ==
1. +nm), even after 96 hours the insulation N under the circuit 6
Three parts did not peel off, but the conventional one (first part) did not peel off.
Figure 0) had peeled off and could not be put to practical use.

Further, since the processing is carried out in line with the groove 5, the exposed area of the metal plate 1 at the processed end face is reduced, and the rust prevention properties are improved accordingly. If grooves 2 are provided on both sides of the metal plate 1 as shown in Figure #JS3, cutting or drilling can be performed from both sides of the metal base laminate A. Furthermore, if the low thermal conductivity insulator 9 contains an inorganic filler, the difference in coefficient of thermal expansion between the through hole and the metal plate 1 will be reduced, improving thermal shock resistance and further increasing reliability.

[Effects of the Invention] In the present invention, a groove is formed in the portion of the metal plate corresponding to the peripheral area of the location where the heat generating component is planned to be mounted, and this groove is filled with a low heat conductive insulator, so that metal base printing is possible. When heat-generating components are mounted on a wiring board, the low thermal conductivity insulating material within the groove will reduce the thermal conductivity of the metal plate, which will not adversely affect other parts of the metal plate that are sensitive to heat. If a metal-based printed wiring board is formed by cutting or perforating the groove from the side by pressing with a mold or cutting with a shear, there will be no sagging on the stamping side or notch side and the groove The insulating layer under the formed circuit will not peel off from the metal plate, and the insulating layer under the formed circuit will not peel off from the metal plate.Moreover, since the processing is performed in line with the groove, the exposed area of the metal plate will be reduced at the processed edge. The smaller the size, the better the rust resistance, and thus a metal-based printed wiring board that has rust prevention, moisture resistance, and water resistance, and high M-conductivity can be obtained.

[Brief explanation of the drawing]

1 and 2 are a plan view and a sectional view showing one embodiment of the present invention, Pt53 is a plan view showing another embodiment of the present invention, and FIGS. 4(a), (b), and 5 (a), (b), and (c) are sectional views showing still other embodiments of the present invention, FIG. 6 is a sectional view showing a metal-based printed wiring board obtained according to the embodiment shown in FIG. 1, and FIG. The figure is a cross-sectional view showing a state in which a circuit is formed on the metal-based printed wiring board shown in FIG.
Figures 8 and 9 are cross-sectional views and partially omitted cross-sectional views showing metal-based printed wiring boards obtained from conventional examples;
The figure is a cross-sectional view showing a state in which a circuit is formed on the metal-based printed wiring board obtained from the above, in which A is a metal-based laminate, B is a metal-based printed wiring board, 1 is a metal plate,
2 is an insulating layer, 3 is a metal foil, 4 is a groove, and 9 is a low heat conductive insulator. Agent Patent Attorney Ishi 1) Chief 7 Figure 3 Figure 2

Claims (1)

[Claims] (1) A metal base laminate formed by adhering metal foil to a metal plate through an insulating layer, with grooves formed in the part of the metal plate corresponding to the periphery of the area where heat generating components are planned to be mounted. A patented metal-based laminate whose grooves are filled with a low thermal conductive insulator.