JPH07232341A - Manufacture of laminated plate - Google Patents

Abstract

PURPOSE:To prevent a laminated plate which employs fluororesin from swelling and peeling by inserting a cushioning material having a specific size between a heating platen and a metallic plate nearest the heating platen to form the laminated plate. CONSTITUTION:A body 7 to be pressed comprises a laminate wherein a predetermined number of prepregs 3 prepared by impregnating a base material with fluororesin varnish, or a predetermined number of prepregs 3 and fluororesin films 4, is laminated on one another with a metallic foil 6 disposed on one face or on both faces of a component thus laminated between paired metallic plates 2. The bodies 7 thus prepared are formed under heating and pressure between paired heating platens 1. In this case, the forming is performed by inserting each of cushioning materials 5, of which the length of each side of the plane is shorter than the length of each side of the body 7 and is at least 70% thereof, between the heating platen 1 and the metallic plate 2 nearest the heating platen 1. By this method, pressure to be applied on the bodies 7 at the time of the forming under pressure does not act on the ends of the bodies 7 sandwiched between the metallic plates, and a laminated plate becomes more uniform.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a laminated board used as a printed wiring board used in electronic equipment, electric equipment, computers, communication equipment and the like.

[0002]

2. Description of the Related Art FIG. 3 is a diagram showing a structure between hot plates when a laminated plate is formed.

As shown in FIGS. 3 and 1A, as a method of manufacturing a laminated plate, a plurality of metal plates 2 are sandwiched between a pair of heating plates 1 and the metal plates 2 and the metal A predetermined number of prepregs 3 in which a base material is impregnated with a fluorinated resin varnish or the prepregs 3 and a film 4 of the fluorinated resin are laminated between the plate 2 and the metal foil 6 on one side or both sides thereof as required. After sandwiching the pressed body 7 composed of a laminated body in which is arranged, the cushion material 5 is inserted between the hot platen 1 and the closest metal plate 2 of the hot platen 1, and the pressed body 7 is heat-molded under pressure. A method of cooling to obtain a laminated plate is known. As the cushion material 5, generally, a kraft paper or a laminated board having substantially the same structure is used, and is used to make uniform the pressure variation in the plane of the metal plate 2 which occurs at the time of pressurization. Since the cushion material 5 is generally the same size as or larger than the body 7 to be pressed, the pressure applied to the body 7 to be pressed during the pressure molding is excessively applied to the end portion of the body 7 sandwiched between the metal plates 2. It takes. Therefore, in the laminated plate manufactured from the pressure target body 7, the thickness of the end portion is smaller than the thickness of the center portion.

Further, especially in the case of the structure including the film 4,
The air remaining between the prepreg 3 and the film 4 or between the film 4 and the film 4 is trapped due to the excessive pressure applied to the end of the body 7 to be pressed, and is not discharged during the molding. , The prepreg 3 and / or the film 4
In the case of containing a fluororesin such as polytetrafluoroethylene, when the melt viscosity is high and the pressure is applied to the ends excessively, the ends are covered with the melt with high viscosity and remain inside the laminate. The trapped air is easy to be blocked. That is, there is a drawback in that the laminated plate is swollen or peeled off.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to eliminate the above-mentioned drawbacks, and its object is to prevent swelling or peeling of a laminate using a fluororesin, It is an object of the present invention to provide a method for manufacturing a laminated plate having improved moldability.

[0006]

According to a first aspect of the present invention, there is provided a prepreg 3 in which a base material is impregnated with a fluororesin varnish between a pair of metal plates 2 and 2. Alternatively, a predetermined number of the prepreg 3 and the fluororesin film 4 are laminated, and one or both surfaces thereof are
In a method for manufacturing a laminated plate in which a pressure-receiving body 7 composed of a laminated body on which a metal foil 6 is arranged is heated and pressed between a pair of hot plates 1 and 1, the hot plate 1 and the hot plate 1 are closest to each other. Between the metal plate 2 and the metal plate 2, a cushion material 5 having a length of each side of the plane shorter than a length of each side of the pressure-receiving body 7 and 70% or more of the length of each side of the pressure-receiving body 7 is provided. It is characterized by being inserted and molded.

The method for producing a laminated board according to a second aspect of the present invention is characterized in that the prepreg 3 and / or the film 4 contains polytetrafluoroethylene.

[0008]

According to the method for manufacturing a laminated plate of the present invention, a plurality of pairs of metal plates 2 are sandwiched between the upper and lower heating plates 1,
A prepreg 3 obtained by impregnating a fluorinated resin varnish or a pressed body 7 made up of the prepreg 3 and a film 4 of a fluorinated resin is sandwiched between the pair of metal plates 2 to form a hot platen 1 and a hot platen 1 The cushioning material 5 is inserted between the cushioning material 5 and the closest metal plate 2, and the length of each side of the plane of the cushioning material 5 is shorter than the length of each side of the pressed body 7 and Since it is 70% or more of the length of each side of, the pressure applied to the pressed body 7 at the time of pressure molding does not excessively apply to the end portion of the pressed body 7 sandwiched by the metal plate 2, and Be uniform. Therefore, the laminated plate manufactured from the pressure-receiving body 7 has a uniform thickness.

Further, even in the case of the structure including the prepreg 3 and the film 4 containing polytetrafluoroethylene having a high melt viscosity, it was between the prepreg 3 and the film 4 or between the film 4 and the film 4. Air is discharged so as to be squeezed out from the end of the body 7 to be pressed during molding. That is, swelling or peeling of the laminated plate is prevented.

The present invention will be described in detail below. Figure 1
As shown in FIGS. 1 (a) and 1 (b), a plurality of metal plates 2 are sandwiched between a pair of heating plates 1 and 1 and a fluorine-based material is placed between the metal plates 2. A prepreg 3 in which a base material is impregnated with a resin varnish, or a predetermined number of the prepreg 3 and a film 4 of a fluororesin are laminated, and a laminate formed by arranging a metal foil 6 on one surface or both surfaces of the prepreg 3 as required. The cushion member 5 is inserted between the hot platen 1 and the closest metal plate 2 of the hot platen 1 with the pressure plate 7 interposed therebetween, and the pressed body 7 is inserted between the pair of hot platens 1 and 1. In the method of heat and pressure molding, the metal plate 2 has a plate thickness of 1 to 3 m.
A stainless steel plate or an iron plate having a surface of chrome plated with chromium is used, and the base material of the prepreg 3 that constitutes the pressure-receiving body 7 is glass, a woven fabric of inorganic fibers such as asbestos, a nonwoven fabric or a matte or other polyamide, Polyvinyl alcohol, polyester, organic synthetic fibers such as polyacrylic and natural fibers such as pulp paper and cotton, the resin varnish to be impregnated is a fluorine-based resin, for example polytetrafluoroethylene as a main component, if necessary epoxy resin, Including thermosetting resin such as phenol resin, melamine resin, polyimide resin,
A fluorinated resin varnish containing a flame retardant such as a silane coupling agent or antimony trioxide may be used. If necessary, a metal foil 6, for example, a copper foil having a thickness of 12 μm to 70 μm may be arranged on the upper and lower sides of or one outside of the body 7 to be pressed.

As shown in FIG. 1 (b) and FIG. 2, when the above-mentioned pressed body 7 is heated and pressed, a cushion material 5 is placed between the hot platen 1 and the metal plate 2 closest to the hot platen 1. Insert and shape. The cushion material 5 has substantially the same structure as the kraft paper or the laminated plate, and is used to make uniform the pressure variation in the plane of the metal plate 2 that occurs when the pressure is applied. The length of each side of the cushion member 5 is shorter than the length of each side of the body 7 to be pressed, and is limited to 70% or more of the length of each side of the body 7 to be pressed.

That is, when the length of each side of the flat surface of the cushion member 5 is longer than the length of each side of the pressed body 7, the pressure applied to the pressed body 7 during the pressure molding is sandwiched between the metal plates 2. The end of the pressed body 7 is excessively applied. Therefore, in the laminated plate manufactured from the pressure-receiving body 7, the thickness of the end portion tends to be smaller than the thickness of the center portion. Further, particularly in the case of the configuration including the film 4, the air remaining between the prepreg 3 and the film 4 or between the film 4 and the film 4 may be excessively applied to the end portion of the pressure-receiving body 7. It is trapped, does not discharge during molding and remains inside the laminate,
Swelling or peeling occurs on the laminated plate. In particular, when the prepreg 3 and / or the film 4 contains polytetrafluoroethylene, the melt viscosity is high, and when the pressure is excessively applied to the end, the end is covered with the melt having high viscosity,
Air remaining inside the laminate is easily blocked.

When the length of each side of the flat surface of the cushion member 5 is less than 70% of the length of each side of the body 7 to be pressed, the pressure is concentrated in the central portion of the laminated plate, and The pressure applied to the edge becomes weak, and due to defective molding of the edge of the laminate,
Peeling occurs.

When the length of each side of the flat surface of the cushion member 5 is shorter than the length of each side of the body 7 to be pressed and is 70% or more of the length of each side of the body 7 to be pressed, the load is increased. The pressure applied to the pressed body 7 during the pressure forming does not excessively apply to the end portion of the pressed body 7 sandwiched between the metal plates 2 and becomes more uniform.
Therefore, even in the case of the structure including the fluorine resin film 4, the prepreg 3 and the fluorine resin film 4 are included.
The air that is present between or between the fluorine-based resin film 4 and the fluorine-based resin film 4 is discharged so as to be squeezed out from the end of the body 7 to be pressed during molding. That is, swelling or peeling of the laminate is prevented, and moldability is improved.

[0015]

EXAMPLES The present invention will be specifically described below with reference to examples. (Example 1) A prepreg obtained by impregnating a glass cloth with polytetrafluoroethylene used as a fluororesin varnish between a metal plate 2 made of a stainless steel plate having a thickness of 2 mm and having a surface plated with chromium. 3 and 5
A film 4 made of polytetrafluoroethylene having a thickness of 0 μm was laminated, and a copper foil having a thickness of 35 μm was arranged as a metal foil 6 on the upper and lower sides of the prepreg 3 to form a pressed body 7 having a length and width of 1020 mm. As the cushion material 5, both vertical and horizontal are 9
Using a laminated plate having the same structure as the body 7 to be pressed having a thickness of 00 mm and a thickness of 2 mm, the temperature is 380 ° C., and the pressure is 40 kg / cm ² .
The pressed body 7 was molded under the condition of 20 minutes to obtain a laminated plate.

This laminate was visually inspected. As a result, the laminate had a uniform thickness, and the laminate did not swell or peel. (Comparative Example 1) A laminated board was obtained in the same manner as in Example 1 except that the cushion material 5 having a length and width of 1020 mm was used.

This laminate was visually inspected. As a result, the laminated plate was swollen and peeled. (Comparative Example 2) A laminated board was obtained in the same manner as in Example 1 except that the cushion material 5 having a length and width of 600 mm was used.

This laminate was visually inspected. As a result, the laminated plate was peeled off at the edges.

[0019]

According to the method for manufacturing a laminated board of the present invention, the length of each side of the plane of the cushion material is shorter than the length of each side of the body to be pressed, and the length of each side of the body to be pressed is smaller than that of the body to be pressed. Since it is 70% or more, the pressure applied to the pressure-receiving body during the pressure forming does not excessively apply to the end portion of the pressure-receiving body sandwiched by the metal plates, and becomes more uniform. Therefore, the laminated plate manufactured from the pressure-receiving body, even in the case of a structure containing a film of a fluororesin, between the prepreg containing the fluororesin and the film of the fluororesin, or the fluororesin The air between the film of No. 1 and the film of fluororesin is discharged so as to be squeezed out from the end of the body 7 to be pressed during molding. That is, swelling or peeling of the laminated plate is prevented.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a method for manufacturing a laminated board according to an embodiment of the present invention, in which (a) is a cross-sectional view of a main part of a body to be pressed,
(B) is sectional drawing which shows the laminated constitution between heating plates.

FIG. 2 is a plan view showing the relationship between the body to be pressed and the cushion material according to the embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a layer structure between heating plates according to a conventional example.

[Explanation of symbols]

 1 Hot Plate 2 Metal Plate 3 Prepreg 4 Film 5 Cushion Material 6 Metal Foil 7 Pressed Body

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Claims (2)

[Claims] 1. A prepreg (3) in which a base material is impregnated with a fluororesin varnish between a pair of metal plates (2) and a metal plate (2) or a film of the prepreg (3) and a fluororesin ( 4) and a predetermined number of layers are laminated, and on one side or both sides of the pair of hot plates (1) and a hot plate (1) are provided a pressure-receiving body (7) consisting of a laminated body in which the metal foil (6) is arranged. In the method for producing a laminated plate in which heat and pressure molding is performed between the hot plate (1)
Between the metal plate (2) closest to the hot platen (1),
A cushioning material (5) is inserted in which the length of each side of the plane is shorter than the length of each side of the pressed body (7) and is 70% or more of the length of each side of the pressed body (7). A method for producing a laminated plate, which comprises: 2. The method for producing a laminated board according to claim 1, wherein the prepreg (3) and / or the film (4) contains polytetrafluoroethylene.