JPH0360308B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous manufacturing method for metal foil-clad laminates.

A laminate made of paper, glass cloth, glass paper, etc. as a base material, laminated with multiple resin-impregnated base materials impregnated with a resin liquid, and cured, and a metal foil on one or both sides of the laminate. Metal foil laminates are used as insulating boards and printed wiring boards.

Conventionally, these laminates were manufactured using a batch method in which prepregs obtained by impregnating the base material with resin varnish and drying were stacked and molded by pressurizing and heating. A continuous method has been developed that performs resin impregnation, lamination, curing, etc. while continuously conveying materials, and is attracting attention. For example, see JP-A-55-4838 and JP-A-56-98136, etc. according to the present application.

In the above continuous method, a plurality of substrates impregnated with resin liquid are combined while being conveyed, and a metal foil is pasted on the top surface of the combined laminate, and a carrier sheet is pasted on the bottom surface of the combined laminate using laminating rolls, and the material is sandwiched between them. It passes through a curing furnace and is cured. An uncured laminate that has entered the curing furnace receives almost no pressure in the direction perpendicular to the plane of the laminate at the initial stage of curing, that is, at the entrance side of the curing furnace, since the resin is still in a fluid state. However, at the beginning of curing when the impregnated resin is in a sufficiently fluid state, the resin tends to flow toward the ends of the laminate as the uncured laminate advances while remaining substantially horizontal, leaving the curing oven. It was found that the thickness of the laminate was thicker near both ends than in the center, resulting in a lower product yield.

The present invention aims to solve this problem,
A metal that continuously transports multiple sheet-like substrates while impregnating them with a curable resin liquid, laminating the impregnated substrates, pasting metal foil on the top surface of the laminate and a carrier sheet on the bottom surface, and curing the laminate. In the continuous manufacturing method of foil-clad laminates, a carrier sheet wider than the base material and the top metal foil is used as the carrier sheet, and the outer edge of the top metal foil of the base laminate with the metal foil and carrier sheet laminated together is used as a carrier sheet. Provided is a method for continuous production of a metal foil-clad laminate, characterized in that an adhesive tape is applied between the end of the support surface of a carrier sheet and curing is performed while the end of the metal foil is pressed toward the carrier sheet. be done.

As the adhesive tape, it is preferable to use a perforated adhesive tape.

FIG. 1 is a schematic side view of an example of an apparatus for producing a single-sided metal foil-clad laminate by carrying out the method of the present invention.

A base material, for example kraft paper 2 made of cellulose fibers, wound around a roll 1 is continuously conveyed and enters a pretreatment chamber 3 . In the drawing, three substrates are shown to be conveyed at the same time, but it goes without saying that the number of substrates can be increased or decreased as appropriate depending on the final thickness of the laminate. The base material 2 then enters the resin liquid impregnation chamber 4, is impregnated with the resin liquid, passes between a pair of squeeze rolls 5, and is combined. At that time, roll 7
A metal foil 8 fed out from the roll 9 is coated with an adhesive and laminated on the top surface of the laminate of impregnated base materials, and a carrier sheet 10, such as a polyester film, fed out from the roll 9 is placed on the bottom surface of the laminate onto the roll 5. It is twisted and pasted together. The laminate in an uncured state thus obtained is placed in a curing furnace 1.
2, and as it travels through it, it is heated and hardened. The lower carrier sheet 10 is peeled off from the laminate 14 leaving the curing furnace 12 by a roll 13 and wound up as a roll 11. Next, the laminated plate 14 is trimmed at both end portions by a rotary cutter 18, and cut to a required length by a guillotine cutter 19. The previous part of this device was published in the previously cited Japanese Patent Application Publication No. 55-4838 by the present applicant.
No. 56-98136.

In the case of a double-sided metal foil-covered laminate, the metal foil is also bonded to the lower surface as a carrier sheet and does not peel off after curing.

FIG. 2 shows the uncured laminate 20 with the metal foil edges pressed against the carrier sheet using adhesive tape.

The laminate 22 of impregnated base materials is laminated with the carrier sheet 10 on the lower surface and the metal foil 8 on the upper surface by rolls 5, 5, and in this state is placed in the curing furnace 1.
2 undergoes hardening. During lamination, excess resin liquid in the base material layer 22 is squeezed out to form a protruding resin liquid pool 24 on both sides of the base material layer 22.

According to the present invention, an adhesive tape 26 is applied between the outer edge of the metal foil 8 and the edge of the support surface of the carrier sheet 10 at the same time or after the attachment of the metal foil 8 and the carrier sheet 10. For this reason and to prevent the spilled resin liquid 24 from flowing down, the carrier sheet 10 must be wider than the metal foil 8 and the substrate. The adhesive tape 26 is applied to the laminating roll 5, using a method and apparatus similar to that described in the applicant's Japanese Patent Application Publication No. 57-57658.
5 when the metal foil 8 and carrier sheet 10 are laminated to the base layer 22, or may be stretched between the rolls 5, 5 and the curing oven 12. In this case, it is preferable to use an adhesive tape having a large number of holes 28 so that the adhesive tape 26 does not trap air.

By applying it to the adhesive tape 26 in this way,
The ends of the metal foil 8 are pressed toward the carrier sheet 10, and by passing through the curing furnace 12 in this state, the resin liquid flows toward the ends and the edge ends of the laminate become thicker. To prevent. The material of tape 26 may be plastic, cellophane or paper. After leaving the curing furnace 12, the carrier sheet 10 is peeled off from the laminate 14 and taken out, and the adhesive tape 26 is held on the metal foil 8 while the edges of the laminate 14 are trimmed with the cutter 18. or before removing the metal foil 8
It can be peeled off from.

As described above, according to the present invention, in the continuous laminate manufacturing method, it is possible to prevent the thickness of the edge portions of the laminate from becoming thicker than the center portion by a simple method. , thereby increasing the yield of the laminate.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing an example of an overall apparatus suitable for carrying out the method of the present invention, and FIG. 2 is an enlarged perspective view of the laminate in a state before curing. 10 is a carrier sheet, 8 is a metal foil, 22 is a base material layer, 26 is an adhesive tape, and 28 is a hole thereof.

Claims (1)

[Claims] 1 Impregnating a plurality of sheet-like base materials with a curable resin liquid while continuously conveying them, laminating the impregnated base materials, pasting a metal foil on the top surface of the laminate and a carrier sheet on the bottom surface, and In a continuous manufacturing method for metal foil-clad laminates in which curing is performed continuously, a carrier sheet wider than the base material and the metal foil on the top surface is used as a carrier sheet, and the base material laminate is produced by laminating the metal foil and carrier sheet together. A metal foil covering characterized in that an adhesive tape is placed between the outer edge of the upper metal foil and the edge of the support surface of the carrier sheet, and curing is performed while the edge of the metal foil is pressed toward the carrier sheet. Continuous manufacturing method for laminates. 2. The method of item 1, wherein the adhesive tape is perforated adhesive tape.