JPS58197895A - Printed circuit metal 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 an insulating substrate for printed wiring.

Conventionally, 9Pc boards made of phenol or the like with a conductive film formed thereon have been widely used, but recently, attempts have been made to use metal plates as substrates in order to promote heat dissipation. Naturally, an insulating film is formed on a metal substrate, but pinholes occur and the insulation is impaired, and when circuit components are attached to the conductive film on the insulating layer with solder, the insulating layer has Ushida and flux resistance. It has the problem of deterioration.

This invention was made in view of these points, and provides a metal substrate for printed wiring that improves heat dissipation, prevents deterioration of insulation due to pinholes, and has sufficient resistance to soldering. The purpose is to scale.

This invention laminates at least three insulating resin layers on a metal plate, and uses a resin with good heat resistance and adhesion for the first layer to prevent pinholes and peeling, thereby preventing dielectric breakdown. By using a resin with high solder resistance and flux resistance as the final layer resin, it can withstand the soldering of circuit components sufficiently, and by mixing a highly insulating material into the intermediate layer, it can be insulated. It is constructed so that the withstand pressure can be increased considerably.

An embodiment of the present invention will be described based on the drawings.

(1) is, for example, a chassis of an electrical device, and a metal plate (2) serving as a base for a metal substrate is screwed onto the chassis (1). Of course, the chassis (1) itself may be used as the base of the metal plate. On the surface of this metal plate (2), an insulating resin layer (hereinafter referred to as A) made of bismaleimidoboreazine, polyvinylphenol, polyimide, or the like having excellent heat resistance and adhesion is printed as a first layer.

The third layer, which is the final layer, is printed with an insulating resin layer (hereinafter referred to as C) made of epoxy, melamine, or polyester, which has good solder resistance and flux resistance, and the second layer, which is the middle layer, has high insulation. Substance A or C such as silica powder in alumina ship
An insulating resin layer (hereinafter referred to as B) mixed in is printed. Then, a conductive film (3) is formed on the C,
An electronic component (4) is soldered to this conductive film (3). I"'""'1jll In such a configuration, the base of the metal substrate is the metal plate (1), which has extremely high heat dissipation.Also, the single layer A has high adhesion and excellent heat resistance, so There are no problems with pinholes or peeling, and the insulation is excellent.Also, the third layer C has good solder resistance and flux resistance, so it is resistant to solder and flux damaged by heat during soldering. It will not be violated.Moreover, since the intermediate layer B is an insulating resin mixed with a high insulating substance, the dielectric strength voltage is 4.7 to 0 at AC.
KV, and can withstand sufficiently as a substrate for a discharge lamp device.

Table 1 As shown in Table 1, the first layer is made of resin such as bismaleimide or polyvinylphenol-based polyimide, which has high adhesion and heat resistance, and the final layer is made of epoxy or melamine, which has high solder resistance and 7 lux resistance. The structure of the present invention using resin such as polyester or polyester is sample 1. It is clear that the sample IO, which has insulation resin B mixed with a high insulator in the intermediate layer, has a much higher dielectric strength voltage than the others.

Since this invention is configured as described above, it is possible to improve the heat dissipation property of the metal plate, and by using an insulating resin with excellent heat resistance and adhesion as the first layer, it is possible to prevent pin holes. It can prevent peeling and increase insulation properties, and
By using an insulating resin with high solder resistance and 7 lux resistance for the final layer, it can sufficiently withstand the soldering of circuit components, and by incorporating a high insulating material in the middle layer, it has extremely high withstand voltage. It has the advantage of being able to be used as an insulating substrate for a discharge lamp device.

[Brief explanation of the drawing]

The drawing is a partially sectional side view showing an embodiment of the present invention.

Claims (1)

[Claims] 1. An insulating resin layer with excellent heat resistance and adhesion printed as a first layer on a metal plate and an insulation with excellent solder resistance and flux resistance printed as a final layer. 1. A metal substrate for printed wiring, characterized in that at least three insulating resin layers including a resin layer are laminated and printed. 2. At least an insulating resin layer with excellent heat resistance and adhesion printed on the metal plate as the first layer and an insulating resin layer with excellent solder resistance and flux resistance printed as the final layer. 1. A metal substrate for printed wiring, characterized in that three insulating resin layers are laminated and printed, and a highly insulating material is mixed into the insulating resin layer located in the middle layer.