JPH01257045A - Manufacture of laminated sheet - Google Patents

Abstract

PURPOSE:To manufacture inexpensively and effectively one side copper clad laminated sheet which is superior in electric insulation properties, electric characteristics and heat resistance by a method wherein a single or several sheets of piled up prepreg comprised by impregnating glass cloth with fluorine resin and calcining the same, both sides are placed between metallic foils for forming a skin layer and at least one side out of the metallic foils is removed through corrosion. CONSTITUTION:A glass cloth base material is immersed into fluorine resin dispersion for impregnation, dried with infrared ray and formed through calcination. Several sheets of prepreg are piled up, both sides of them are put between metallic foils and heating/ pressurization are performed for laminate molding. An aluminum foil or a copper foil of 5-50mum in thickness is used as the metallic foil. In the case where the copper and aluminum foils are used respectively for one side and the other side as the metallic foil, since only the aluminum foil can be removed through corrosion when a sodium hydroxide solution or dilute hydrochloric acid is used as a corrosive liquid, one side copper clad laminated sheet can be manufactured easily even without performing specific mask treatment. Since the metallic foil is used for a mold release sheet at the time of laminate molding of a laminated sheet, mold release after molding becomes easy. Then since the metallic foil is made the aluminum foil, removal through corrosion can be performed easily after molding.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for inexpensively and efficiently producing a single-sided copper-clad laminate with excellent electrical insulation, electrical properties, and heat resistance.

<Prior Art and its Problems> Conventionally, as a material with good electrical insulation, heat insulation, and heat resistance, a laminated and molded prepreg made by impregnating and firing a fluororesin into a glass cloth has been used.

Tetrafluoroethylene resin is generally used as the fluororesin, and it alone has a volume resistivity of 1018 Ω・cm and a thermal conductivity of 6 Xl0-'cat/C#1-sec.
Although a melting point of 327°C has been achieved, delamination tends to occur due to lamination at high temperatures (and there was no suitable release sheet that could withstand repeated use. It was not possible to efficiently manufacture the single-sided copper-clad laminate used in this process.

<Problems to be Solved by the Invention> The present invention discloses a method for manufacturing a laminate, in which prepregs are easily released from the mold and delamination is less likely to occur when a plurality of prepregs are stacked and heated and pressurized at high temperature. It's about doing.

Means for Solving the Problems In the present invention, the first step is to stack several sheets of prepreg made by impregnating glass cloth with a fluororesin and firing it, sandwiching both sides with metal foil to form a skin layer, and then forming a layered layer. There are cases where one side of the metal foil is made of aluminum foil and the second step is a process of corroding and removing only the aluminum foil over the entire surface, and a case where a prepreg subjected to low temperature plasma treatment is laminated and aluminum is formed on both sides. This problem was solved by disclosing a manufacturing method in which the second step is to heat and pressurize the metal foils to bring them into close contact, and finally to corrode and remove the aluminum foils on both sides.

Specifically, a glass cloth base material is impregnated with a fluororesin dispersion, dried with infrared rays, and then fired.

Several sheets of this prepreg are layered, sandwiched between metal foils on both sides, and heated and pressurized to form a laminate.

As the metal foil, aluminum foil, copper foil, etc. with a thickness of 5 to 50 μm can be used.

Tetrafluoroethylene disversion is used as the fluororesin disversion.

Corrosion removal is done chemically using a corrosive solution. When the metal foil is aluminum or aluminum alloy, the corrosive liquid is sodium hydroxide solution (NaOH, 150g to 180g/f).
fi+A1 6-20g/l), dilute hydrochloric acid (HCI, 50
%VOt, ), ferric chloride solution (FeC1z, 120~
For copper and copper alloys, ferric chloride molten tL (Fect:+, 30-40 g/l) is used.
), copper chloride solution (CuCIz, 30-35 g/
I! , ).

When M4 fa is used as the metal foil on one side and aluminum foil is used on the other side, if a sodium hydroxide solution or dilute hydrochloric acid is used as the corrosive liquid, only the aluminum foil can be corroded and removed, so a special mask treatment is required. Single-sided copper-clad laminates can be easily manufactured even without it.

In addition, low-temperature plasma processing is performed by passing a low-pressure gas (air, oxygen, helium) into the low-temperature plasma processing equipment that can reduce pressure, and applying high-frequency (10K to 100M) gas between the electrodes.
This is done by applying an electric field of Hz).

Effect> By using gold foil as a release sheet during lamination molding in the method for producing a laminate of the present invention, it becomes easy to release the mold after molding, and by using aluminum foil as the metal foil, It can be easily corroded and removed after molding.

<Example 1> A glass cloth (108A, manufactured by Arisawa Seisakusho Co., Ltd.) was impregnated with a tetragonal ethylene resin dispersion (manufactured by Asahi Glass Co., Ltd., Fluon AD-1) so that the resin amount was 70% by weight. After drying, the mixture was heated and melted at a temperature between 300°C and 400°C to obtain prepreg a.

This prepreg 001 sheet was sandwiched between 0.01mm thick aluminum foil 04 and 0.018mm thick copper foil 06) and molded at a pressure of 30Kgf/c at 4.370°C for 60 minutes at 10 tons.
A metal-clad laminate was obtained by heating and pressure forming in an atmosphere of
110' g/l) to corrode and remove only the aluminum foil (q) to obtain a single-sided copper-clad laminate. (Figure 1b) <Example 2> Tetrafluoroethylene resin dispersion (manufactured by Asahi Glass Co., Ltd., Fluon AD-1) was placed on glass cloth (manufactured by Arisawa Seisakusho Co., Ltd., 108A) so that the resin amount was 70% by weight. Impregnated with. After drying, it was heated and melted at a temperature between 300'C and 400C to obtain a prepreg.

This prepreg is Q, 20m/+ in 1torr air.
Passed through the processing machine at a speed of 13.56 MHz,
5 was subjected to low-temperature plasma treatment by applying - high frequency power.

The thickness of the top and bottom surfaces of 25 sheets of prepreg is 0°0.
Place 2n+m aluminum foil 04) and apply a molding pressure of 30kgf.
/c+a, was heated and press-molded at 370° C. for 60 minutes in an atmosphere of 10 torr to obtain a metal-clad laminate having a thickness of 21 mm. (Fig. 2a) This laminate was heated in an iron chloride solution (F) at 50°C.
The aluminum foil Q41 was corroded by immersion in eCl2.150g/2) to obtain a laminate. (FIG. 2b) The obtained laminate had excellent adhesion strength between the eyebrows and satisfactory heat resistance and electrical insulation properties.

<Effects of the Invention> Since the present invention is configured as explained above,
This produces the effects described below.

By sandwiching the laminate between metal foils, it can be easily released from the mold after laminate molding. Furthermore, metal foils can be corroded with corrosive liquids, and laminates can be easily manufactured.

In addition, if the metal foil on one side is made of inexpensive aluminum and the metal foil on the other side is made of copper, only the aluminum foil can be selectively corroded by alkali treatment or acid treatment, making it extremely easy to laminate one side with copper clad. A board is obtained. Furthermore, since the copper foil surface is automatically degreased during this corrosion process, good adhesion strength can be obtained when used as a multilayer board.

When fluorine resin-impregnated prepreg is subjected to low-temperature plasma treatment, peeling of the base material between the eyebrows after lamination molding can be suppressed.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram showing the manufacturing process of the laminate disclosed in Example 1, and FIG. 2 is a M
It is a cross-sectional explanatory view showing the manufacturing process of the J-layer board. 00)... Fluorine resin impregnated prepreg θ2...
... Fluorine resin-impregnated prepreg treated with low-temperature plasma 04 ... Copper foil 06) ... Aluminum foil patent filed by Toppan Printing Co., Ltd. Representative Kazuo Suzuki Figure 1 sumi 2 drawing

Claims (1)

[Claims] 1) A method for manufacturing a laminate comprising the following steps. a. The first step is to form a skin layer by sandwiching metal foil on both sides of prepreg, which is made by impregnating glass cloth with fluororesin and firing it, either singly or in layers. b. A second step of removing corrosion from at least one side of the metal foil. A method for manufacturing a laminate, characterized by comprising the above two steps. 2) The method for manufacturing a laminate according to claim 1, wherein one of the two metal foils is made of copper foil and the other is aluminum foil, and the aluminum foil is removed by corrosion. 3) The method for manufacturing a laminate according to claim 1, wherein the prepreg is subjected to low temperature plasma treatment before lamination. 4) The method for manufacturing a laminate according to claim 1 or 3, wherein the two metal foils are aluminum foils. 5) The method for manufacturing a laminate according to claim 4, wherein both of the two metal foils are removed by corrosion.