JPH0473144A - Manufacture of metal foil clad laminated sheet - Google Patents

Abstract

PURPOSE:To prevent the adhesion of a resin to steel belts by continuously supplying cover sheets covering both end surfaces in the longitudinal direction of the laminate heated and pressed between upper and lower belts to the space between the upper and lower belts so as to extend between the metal foils applied to the upper and lower surfaces of the sheet. CONSTITUTION:A laminate 3 wherein metal foils 3 are superposed on the upper and lower lower surfaces of a prepreg 1 is heated by dielectric heating to bring the resin in the prepreg 1 to a molten state and subsequently introduced into the space between a pair of upper and lower belts 4. Since pressure heating devices 8 such as hot plates are arranged inside the belts 4, the laminate 3 is heated and pressed not only to cure the resin (a) of the prepreg 1 but also to integrally laminate and bond the prepreg 1 and the metal foil 2. When the prepreg 1 is heated by dielectric heating to melt the resin, gas is generated by the melting of the resin (a) or the molten resin (a) flows laterally but, since cover sheets 5 are provided to the end parts of the laminate 3 and said end parts are covered with the cover sheets 5, the resin (a) molten to flow laterally flows out from the end parts of the metal foils 2 to be stopped by the cover sheets 5 without being bonded to the belts 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a metal foil-clad laminate for continuous production of a metal foil-clad laminate used as a printed wiring board.

[Prior Art] Conventionally, metal foil-clad laminates are formed by laminating and bonding metal foil on the surface of prepreg, and the lamination and bonding of prepreg and metal foil can be achieved by, for example, bonding metal foil on one or both sides. The prepreg on which the foil is placed is passed between high-frequency loading electrodes and dielectrically heated under no pressure or contact pressure to heat the resin impregnated into the prepreg and melt it, which is then passed between the belts driven by the drum. The resin of the prepreg is cured using a pressure/heating device, thereby bonding and bonding the three layers of the prepreg and metal foil together.

[Problem to be solved by the invention C. However, when melted with resin by dielectric heating,
The molten resin flows out and adheres to the surface of a belt such as a steel belt, and when the molten resin adheres to the belt and hardens, it becomes the metal foil surface of a metal foil-clad laminate that is continuously manufactured. There was a problem in that a metal foil-clad laminate with poor surface quality and having unevenness formed on the surface was manufactured.

The present invention is intended to solve the above-mentioned problems, and its purpose is to manufacture a laminate with good surface quality and which can prevent resin from adhering to the steel plate. The purpose of the present invention is to provide a method for manufacturing a metal foil-clad laminate that allows for the production of metal foil-clad laminates.

[Means for Solving the Problems] In order to achieve the above object, the method for manufacturing a metal foil-clad laminate according to the present invention is such that a long prepreg 1 is continuously fed and a long metal foil 2 is coated on both outer surfaces of the prepreg 1. A laminate 3 in which metal foils 2 are layered on both outer surfaces of the prepreg 1 is continuously fed between the upper and lower belts 4, and heat and pressure are applied between the upper and lower belts 4 to form a metal foil-covered laminate. In order to obtain the product, a covering sheet 5 covering both longitudinal end surfaces of the laminate 3 heated and pressed between the upper and lower belts 4 is continuously placed between the upper and lower belts 4 so as to cover between the metal foils 2 attached above and below. It is made by supplying.

[Function] Since the longitudinal ends of the laminate 3 are covered with the covering sheet 5, the laminate 3 is heated and pressurized.
The molten resin a flowing out from the end of the belt 4 does not adhere to the surface of the belt 4 and harden.

[Example] Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

A prepreg 1 on which a metal foil 2 such as a copper foil is laminated is prepared as a long body by impregnating a base material such as glass cloth or paper with a thermosetting resin such as an epoxy resin and drying it. Then, as shown in FIG. 3, the prepreg 1 is unwound from a roll and continuously supplied between a pair of upper and lower belts 4. Here, the belt 4 has scratches on the surface,
It does not have pinholes, etc., and is wound between a pair of two rolls 4a on the left and right, installed above and below, so that it can run freely up and down, and one of the rolls 4a is used for driving. A metal foil 2 such as a copper foil is also formed into a long length and wound into a roll, which is unwound and superimposed on the outer surface of the outermost layer of the prepreg 1 by a stacking roll 6. When creating a double-sided metal foil clad laminate, two metal foils 2 are placed on both outer surfaces of the prepreg 1 as shown in FIG.
At the same time, a covering sheet 5 such as a heat-resistant resin tape is continuously fed between the upper and lower belts 4 so as to cover the ends of the laminate 3 while being bent into a U-shape. . That is, as shown in FIG. 2, the covering sheet 5 is arranged so that its end extends between the metal foils 2 disposed above and below the prepreg 1, and the longitudinal ends of the laminate 3 are covered with It is in a state covered by the sheet 5. Here, the metal 732 can be either coated with an adhesive or a foil made of a combination of an aluminum carrier and an ultra-thin steel foil. The laminate 3 in which the prepreg 1 and the metal foil 2 are stacked is passed between the upper and lower high-frequency loading electrodes 7, and the laminate 3 is impregnated by dielectric heating under no pressure or contact pressure. Preferably, the resin a is heated to about 100 to 140°C. On this occasion,
It is desirable to use contact pressure to electrically connect the electrode 7 and the metal foil 2, and dielectric heating is performed until the resin a in the prepreg 1 melts and becomes fluid. When dielectrically heated in this way, the heating temperature becomes higher inside the prepreg 1 rather than at the surface, and as in the case of external heating using electric heating, the surface is heated higher than the inside, causing the prepreg 1 to heat up to a higher temperature. The curing reaction of the resin progresses quickly on the surface area, and there is no longer a situation where the air bubbles in the prepreg 1 cannot be removed completely, making it easier to remove air bubbles in the next process and reducing the amount of air bubbles remaining in the prepreg 1. It will be possible. After the resin in the prepreg 1 is melted by preheating by dielectric heating in this manner, the laminate 6 is introduced between the pair of upper and lower belts 4. Pressure is applied to the laminate 3 between the belts 4, and a heating plate or pressure heating device 8 is disposed inside each belt 4, and this pressure heating also applies pressure to the laminate 3. The resin a of the prepreg 1 is cured by heating, and the prepreg 1 and the metal foil 2 are laminated and bonded together. Here, when the prepreg 1 is dielectrically heated to melt the resin, gas is generated due to the melting of the resin a, and the melted resin a flows to the side, but as described above, the edges of the laminate 3 is provided with a covering sheet 5, and the ends of the laminate 3 are covered with the covering sheet 5, so that the resin a that melts and flows laterally is a metal foil, as shown in FIG. 2
The resin a flows out from the end of the belt 3 and is stopped by the covering sheet 5 without adhering to the belt 3, so that the resin a that flows out does not adhere to the surface of the belt 4 and harden. There is.

Then, the cured laminate 3 is guided by guide rolls 9 and cut at predetermined locations using a cutting machine, for example, to obtain a metal foil-clad laminate having a predetermined length. Here, since the prepreg 1 is preheated by dielectric heating, there is virtually no difference in the heating rate between the prepreg 1 and the metal foil 2 when they are heated between the belts 3. This makes it possible to prevent the occurrence of wrinkles in the metal foil due to the difference in thermal expansion between the metal foil and the metal foil.

In the illustrated embodiment, the flip-preg 1 has a single layer, but it may have a plurality of layers stacked one on top of the other.

[Effects of the Invention] As described above, the method for producing a metal foil-clad laminate of the present invention is as follows. Since the covering sheet is continuously supplied between the upper and lower belts so as to span between the foils, the covering sheet supplied between the upper and lower belts is arranged so that the end thereof spans between the metal foils arranged above and below the prepreg. The longitudinal ends of the laminate are covered with a covering sheet, and when the prepreg and metal foil are laminated and bonded together, the molten resin flows out and adheres to the surface of the belt. It is possible to prevent such things as hardening, and it is possible to obtain a metal foil-clad laminate with good surface quality.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, FIG. 2 is a cross-sectional view showing the same effect as above, and FIG. , 3 is a laminate, 4 is a belt, and 5 is a covering sheet. Prepreg 4 to Held 5 Covering Sheet Agent Patent Attorney Stone 1) Long 7th 16th! ! ! Figure 2 Figure 3

Claims (1)

[Claims] [1] By continuously feeding a long prepreg, overlapping a long metal foil on both outer surfaces of the prepreg, and continuously feeding a laminate with metal foil overlapping both outer surfaces of this prepreg between the upper and lower belts. When heating and pressing is performed between the upper and lower belts to obtain a metal foil-clad laminate, covering sheets are added above and below to cover both longitudinal end surfaces of the laminate that is heated and pressed between the upper and lower belts. A method for manufacturing a metal foil-clad laminate, characterized in that the metal foil is continuously supplied between upper and lower belts so as to cover the space between the metal foils.