JPH04191020A - Forming method for laminate - Google Patents

Abstract

PURPOSE:To prevent the outlow of resin from prepreg ends at the time of laminate forming and enhance the surface roughness degree and dimension stability of laminate by forming channels or holes on the surface ends of a metal mirror plate and disposing banks with the given height and length on said channels or holes. CONSTITUTION:Usually a metal mirror plate 1 is made of stainless steel, and channels 5 are formed on the two sides facing each other or four sides, and banks 2 for preventing resin flow are disposed. Required release papers, metallic foils 3, prepregs 4 or the like including banks are placed between the mirror plates 1 and heat pressurized to form a laminate. The height and length of the banks are fixed according to the thickness and size of the laminate to be laminate formed. Especially the height of the banks is not affected by the size of the resin flow at the time of forming. For example, in the case of 1.6mm thickness laminate, approximately 0.3-0.5mm is suitable, and in the case of 0.8mm thickness laminate, approximately 0.15-0.25mm is suitable, and in the case of 0.4mm thickness laminate, 0.08-0.12mm is suitable. As the outflow of resin is prevented by the banks, the thickness of laminates is uniform, and the distribution of resin base is also uniform, and the smoothness of the laminate surface is more superior.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a laminate suitable for use in high-density printed wiring boards, which has excellent plate thickness accuracy and good surface roughness stability in one dimension. It is.

[Conventional technology]

Conventionally, there are methods to reduce the flow of resin from the ends of the prepreg, such as shortening the gel of the prepreg and reducing the molding pressure of the press.However, although these methods are effective to some extent, the flow In order to make prepregs with improved impregnation properties, it was necessary to perform two-stage impregnation, vacuum impregnation, etc., or to use vacuum pressing in order to create prepregs with improved impregnability.

[Invention or problem to be solved]

The present invention prevents resin from flowing out from the ends of the prepreg during lamination molding of the laminate, and improves the surface roughness and dimensional stability of the laminate by arranging a flow-stop embankment at the end of the surface of the metal mirror plate. The purpose is to improve sexuality.

[Means to solve the problem]

The present invention will be explained based on the drawings.

The metal mirror plate 1 used in the present invention is usually made of stainless steel, and is approximately 3 to 3 mm from the edge of its surface, that is, the peripheral edge
At a position of 30 mm, grooves 5 or holes 6 (through or not) are provided on two or four opposing sides as shown in FIGS. 2 and 3. As shown in Figure 1,
A embankment 2 for preventing resin flow with a predetermined height and length is provided on the mirror plate 1.
Place.

Next, necessary release paper or metal foil 3, prepreg 4, etc. are placed between the mirror plates including the paddle guard, and a laminate is formed by heating and pressing.

The height and length of the embankment used in the present invention are determined by the thickness and size of the laminated plate obtained by lamination molding. In particular, the height of the embankment is an important factor that substantially determines its flow prevention effect. This height is almost unaffected by the size of the resin flow during molding, for example], 6 m
In the case of a laminated board with a thickness of m, the thickness is about 0.3 to 0.5 mm, 0.
In the case of a 8 mm thick laminate, it is about 0.15 to 0-25 mm, and in the case of a 0.4 mm thick laminate, it is 0°08 to 0.1
Approximately 2 mm is appropriate.

In the present invention, the embankment provided at the end of the mirror plate prevents the resin from flowing out, so the thickness of the resulting laminate is uniform, the distribution of the resin base material is uniform, and the surface of the laminate is smooth. will also be better. Note that the width of the embankment and the shape of the grooves and holes in the mirror plate for installing the embankment may be determined mainly based on the ease of handling the embankment.

〔Example〕

An example of the present invention is shown.

An epoxy resin-impregnated glass cloth pre-Breguet (approximately 200μ thick) with a width of 530mm and a length of 530m is placed between the metal mirror plates.
) were stacked together, and 18/7 copper foil was stacked on both sides, followed by heating and pressure molding to obtain a copper-clad laminate with a thickness of 16 mm.

The mirror plate used in Koji was 3m away from the opposing ends.
A groove is provided at a position of m, and a height of 0.4 from the mirror plate is placed in this groove.
It has a dike of mm. For comparison, a regular mirror plate was used and laminated in the same way to a thickness of 1.6 mm.
A copper-clad laminate was obtained.

The moldability, thickness accuracy, etc. of the obtained laminate were measured. The results are shown in Table 1.

Table 1 (Measurement method) 1. Formability: The copper foil was removed by etching and the appearance was visually observed.

2. Thickness Accuracy A laminate of 500 mm on a side was cut out, the thickness was measured, and the thickness was determined using the following formula.

Maximum thickness: 3, surface smoothness: Use a surface roughness measuring device MODEL 5E-4A manufactured by Koita Research Institute Co., Ltd.

The value of Rmax was determined using a stylus with a tip radius of 0.5 μm.

〔Effect of the invention〕

According to the molding method of the present invention, a laminate having a uniform thickness and excellent dimensional stability and surface smoothness can be obtained.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing an example of molding according to the present invention. 2nd and 3 are partial perspective views of the mirror plate used in the present invention.

Claims (1)

[Claims] (1) In a laminate forming method in which one or more prepregs impregnated with a thermosetting resin varnish are stacked and sandwiched between metal mirror plates and heated and pressed, the metal mirror plates have grooves at their surface edges. Or, a method for forming a laminate, characterized in that a hole is provided and an embankment having a predetermined height and length is provided in the groove or hole to prevent resin from flowing out from the prepreg during molding.