JPH03247A - Preparation of electric laminated sheet - Google Patents

Abstract

PURPOSE:To prevent the generation of the interfacial release and interlaminar crack between a filler and resin by performing the filling a through-hole with a filler compounded resin powder by rubbing-in. CONSTITUTION:A filler compounded resin powder 4 is received in the through- holes 1 of a metal plate 2 in a slightly large amount so as to rise. This filler compounded resin powder 4 may be scattered on the entire upper surface of the metal plate 2. As the filler compounded resin powder 4, one prepared by powdering the same filler compounded resin as that infiltrated in a prepreg 3a is used. As a filler, a needle-like powder obtained by finely cutting and grinding down a glass fiber or an aramide fiber can be designated. The filler compounded resin powder 4 received in the through-holes 1 of the metal plate 2 having the prepreg 3a temporarily bonded thereto is rubbed in while pressed by a rubbing-in member 10. By this method, the through-holes 1 are filled with the filler compounded resin powder 4 in a relatively easy manner. A filling ratio is enhanced by rubbing-in and the inflow of the resin from the prepreg at the time of molding is reduced and the deviation of the filler in the through- holes is eliminated.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for manufacturing electrical laminates.

[Conventional technology]

A method for manufacturing a multilayer electrical multilayer board using a metal plate as a substrate is disclosed, for example, in Japanese Patent Application No. 73671/1983. The steps of the manufacturing method are shown in FIG. As shown in Figure (a), the metal plate 2 is made of a copper plate, an aluminum plate, etc., and has a through hole 1 with a larger diameter than the through hole at the location where the through hole is to be formed. .

As shown in FIG. 2B, a prepreg 3a is superimposed on one side (lower side) of the metal plate 2 and temporarily adhered thereto. The prepreg 3a is made of steel by impregnating a base material such as glass or paper with a thermosetting resin such as epoxy resin or polyimide and drying it. Since it only serves to close the opening at the bottom of the through hole 1, it is as thin as about 0.1 nm. Next, as shown in the same figure (C),
The through holes 1 of the metal plate 2 are filled with a resin 4 containing fillers such as spherical powder and glass fiber, and then the resin 4 is cured by degassing under reduced pressure and heating. As shown in the figure (d), several composite bodies 6 thus obtained are stacked one on top of the other, and a prepreg 3b is attached to the outer surface of each outermost layer of the composite body 6.
A metal foil 13 such as copper foil is layered via the metal foil 13. At this time, a circuit board 12 with an inner layer circuit formed thereon, such as a single-sided printed wiring board, a double-sided printed wiring board, or a multilayer printed wiring board, is set between each composite body 6 via the prepreg 3b. Make it. By heating and press-molding these laminates, the resin impregnated into the prepreg 3b is cured, and each composite 6 and the circuit board 12 are bonded to each other, thereby causing the metal plate 2 A semi-finished electrical laminate can be obtained in which the and circuit boards 12 are alternately laminated and a metal foil 13.13 is adhered to the outermost layer. Thereafter, a through hole is formed in the semi-finished product by drilling, punching, or the like. The through hole has a smaller diameter than the through hole 1 and passes through the center of the resin 4 portion. As a result, a portion of the resin 4 remains, so that electrical insulation between the inner periphery of the through hole and the metal plate 2 is ensured.

After processing the through-hole, a conductive film is formed on the inner peripheral surface of the through-hole by a method such as copper plating, or an outer layer circuit is formed by etching the metal foil 13, thereby creating a multilayered structure. Circuit lFj using metal plate 2... as a substrate
, 12, . . . and an outer layer circuit made of metal foils 13, 13, a multilayer electrical laminate is completed.

According to the method for manufacturing an electrical laminate, the through hole 1 of the metal plate 2
Since a filler is blended into the resin 4 filled in the through-hole, this filler is exposed on the inner circumferential surface of the through-hole when the above-mentioned drilling process is performed, and the inner circumferential surface becomes an uneven surface, and this uneven surface has an anchor effect, etc. By achieving this, the adhesion of the conductive film (plating layer) applied to the inner peripheral surface of the through hole is improved. In addition, the resin 4 in the through hole 1 is filled by pouring it into the through hole 1 in advance, and the prepreg 3b is filled during molding.
Since it is not filled by flowing molten resin,
If the amount of filler in the resin 4 in the through hole 1 decreases and the uneven surface of the through hole becomes insufficient, or if the filler is unevenly distributed and heat stress is applied, the interface between the filler and the resin may It has the advantage that there is no risk of peeling.

[Problem to be solved by the invention]

However, when the resin 4 filled in the through hole 1 is powder or granule, the above is not necessarily the case. When the resin 4 is a powder, the powder and the filler are put into a hole whose one end is closed with the prepreg 3a, and then the filler-containing resin powder is inserted into a metal plate. It was customary to scrape off along the top surface of 2 with a squeegee. Therefore, since a gap remains between the filler-containing resin particles placed in the through holes 1, the resin from the prepreg 3a flows into the through holes 1 during the heating and pressure molding, and the flow action causes the resin to flow into the through holes 1. The filler in the through hole 1 becomes uneven within the through hole 1. As a result, when a through hole is formed, the uneven surface becomes insufficiently uneven, and when thermal stress is applied, peeling occurs at the interface between the filler and the resin. If the filler is unevenly distributed, as shown in Figure 3, shrinkage force will be generated in the upward and downward directions as a result of heating and pressure molding, and in this state, the prepreg will be applied to the four corners C... marked with X in the diagram. 3a, 3
If the molten resin from B flows in, that part C... will have a significantly higher concentration than the others,
As a result, cracks between the eyebrows were more likely to occur here. For these reasons, it has not been possible to improve through-hole reliability.

In view of the above circumstances, an object of the present invention is to improve through-hole reliability.

[Means to solve the problem]

In order to solve the above-mentioned problems, the method for manufacturing an electric laminate according to the present invention includes filling the through holes of a metal plate with a filler-containing resin powder by rubbing the metal plate, and then filling the metal plate with a filler-containing resin powder. A plurality of sheets are stacked with prepreg interposed therebetween, and the sheets are laminated by heating and pressurizing, and then through-holes are punched using the resin portions in the through-holes.

[For production]

If the filler-containing resin powder is filled into the through hole by rubbing, the filling rate will increase due to the rubbing, and the flow of resin from the prepreg during molding will be reduced, resulting in The unevenness of the filler is eliminated. As a result, even if powder or granular material is used as the resin filled in the through hole, a sufficiently uneven surface due to the filler can be obtained when forming the through hole, and peeling may occur at the interface between the filler and the resin, or between the eyebrows. Cracks will no longer occur.

〔Example〕

Hereinafter, embodiments of the present invention will be explained in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the method for manufacturing an electrical laminate according to the present invention. This figure shows the filling process corresponding to FIG. 2 (C1), and the other steps are the same as those shown in FIG.
As shown in a), the filler-containing resin powder 4 is put into the through hole 1 of the metal plate 2 so as to swell in multiple mouths. This filler-containing resin powder 4 is applied to the upper surface of the metal plate 2.
It may also be sprinkled on the obi. As the filler-containing resin powder 4, a powder similar to that which is impregnated into the prepreg 3a is used. Any filler can be used, but A, Rt O!
, AI! Ox ・Hz O, Ant 0x3H, O,
Talc, Mg02Ca COx, S b 20□, A
Spherical powders such as bz Os, glass fibers such as E glass, D glass, T glass, R glass, and Q glass, and aramid fibers such as Kevlar (manufactured by DuPont) and Technora (manufactured by Kijinsha) are finely cut (cut). An example is needle-shaped powder ground by hand.The amount of filler added to the resin powder 4 is about 50 to 1000 parts by weight, preferably 400 parts by weight, based on 100 parts by weight of the resin. Then,
The filler-containing resin powder 4 placed in the through hole 1 of the metal plate 2 to which the prepreg 3a is temporarily bonded is rubbed while being pressed by a rubbing member 10, as shown in the figure.

The rubbing member 10 is preferably made of, for example, a baren. As a result, the filler-containing resin 4 can be packed into the through hole 1 relatively easily as shown in the same figure (bl). Note that the filler is not mixed in the prepregs 3a and 3b. not present.

As described above, in the method for manufacturing an electric laminate according to the present invention, filling of the filler-containing resin powder into the through holes is performed by rubbing, so that the rubbing increases the filling rate. The flow of resin from the prepreg during molding is reduced, eliminating unevenness of the filler within the through holes. As a result, even if powder or granular material is used as the resin filled in the through hole, a sufficiently uneven surface due to the filler can be obtained when forming the through hole, and peeling may occur at the interface between the filler and the resin, or between the eyebrows. No more cranking.

Incidentally, before the rubbing, vibration may be applied. The filling may be performed in a hidden state without temporarily adhering the prepreg, and the metal plate may be directly laminated and molded.

〔Effect of the invention〕

The method for manufacturing an electrical laminate according to the present invention, as described above, has excellent through-hole reliability.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the method for producing an electrical laminate according to the present invention, and FIG. 1(a) shows the state before the filler-containing resin powder is put into a through hole for filling and rubbed. Figure fb) is a cross-sectional view showing the state after filling, Figure 2 is a cross-sectional view showing the conventional method at each step, and Figure 3 is a cross-sectional view showing the occurrence of glabellar cranks. FIG. ■...Through hole 2...Metal plate 3a, 3b...Prepreg 4...Resin powder containing filler 10...Rubbing member agent Patent attorney Takehiko Matsumoto Figure 1 (b) Figure (d)

Claims (1)

[Claims] 1. After rubbing filler-containing resin powder into the through-holes of a metal plate having through-holes, a plurality of these metal plates are stacked with prepreg interposed therebetween, and this is laminated by heating and pressurizing. A method for manufacturing an electrical laminate, in which a through hole is then punched using a resin portion within the through hole.