JPH0635135B2 - Laminated board manufacturing method - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a method for manufacturing an unclad type laminated plate in which metal foils are not laminated.

[Prior art]

Laminated boards are used after being processed into printed wiring boards, etc.
In addition to metal foil-clad laminates that are laminated with metal foil such as copper foil,
An unclad type laminated plate in which metal foils are not laminated is also used. In manufacturing such an unclad laminate,
Conventionally, for example, the method shown in FIG. 3 has been used. That is, a plurality of prepregs 1 are superposed, the prepregs 1 are set between the metal plates 4 via a release sheet 2 formed of a resin film, and the prepregs 1 are laminated while being heated and pressed by a pressing device. Was done. However, in this method, the metal plate 4
Since only one set of prepregs 1 can be set between them and only one laminated plate A can be produced between the metal plates 4, there is a problem in productivity. For this purpose, as shown in FIG. 4, one set of a plurality of prepregs 1 stacked together is stacked with a release sheet 2 therebetween, and the plurality of sets are sandwiched between metal plates 4. It is used for lamination molding. According to this method, since a plurality of sets of prepregs 1 can be set between the metal plates 4 and a plurality of laminated plates A can be manufactured at the same time, productivity can be improved.

[Problems to be Solved by the Invention]

However, when molding the prepreg 1, stress such as curing shrinkage occurs, but in the method of FIG. 3, since the metal plates 4 are in contact with both surfaces of the laminated plate A to be molded, unevenness is formed on the surface of the laminated plate. Although it can be prevented from occurring, in the method of FIG. 4, since the laminated plate A to be molded except the upper and lower end portions is not in contact with the metal plate 4, a dimensional change occurs due to stress such as curing shrinkage. As a result, unevenness is generated on the surface of the laminated plate A. This dimensional change cannot be suppressed by the release sheet 2. The present invention has been made in view of the above points, and it is an object of the present invention to provide a method for producing a laminated plate while maintaining productivity and without causing unevenness on the surface.

[Means for Solving the Problems]

The method for manufacturing a laminated board according to the present invention is such that a plurality of prepregs 1 are superposed and the superposed prepregs 1 are
Characterized by stacking the release sheets 2 on the upper and lower sides of the sheet to form a set, and stacking a plurality of sets with the metal foil 3 interposed between the sets, sandwiching the set between the metal plates 4, and heating and pressing. It is a thing. Hereinafter, the present invention will be described in detail. The prepreg 1 is made by impregnating a base material such as a glass cloth with a varnish of a thermosetting resin such as an epoxy resin, a phenol resin, an imide resin, and heating and drying the varnish. Then, when manufacturing an unclad laminate using the prepreg 1 cut to a predetermined size, a plurality of prepregs 1 are superposed on each other, and heat-resistant resin films such as triacetate are formed above and below the superposed prepregs 1. The release sheets 2 to be formed are stacked, and a plurality of sets of prepregs 1 are stacked as a set with a metal foil 3 such as a copper foil interposed therebetween as shown in FIG. A plurality of sets of prepregs 1 stacked via such metal foils 3 are sandwiched between upper and lower metal plates 4 formed as mirror plates, and these are stacked in a plurality of stages to be set between hot plates of a press machine. To do. After building up in this way, lamination molding is performed by applying pressure while heating. In this way, a plurality of laminated plates A can be simultaneously molded between the metal plates 4, and since the plurality of laminated plates A are separated by the release sheet 2, they are mutually separated. It can be taken out from between the metal plates 4 without sticking to each other. Further, when the molding is performed as described above, since the metal foil 3 is interposed between the prepregs 1 of each set, each laminated plate A to be molded is in contact with the metal foil 3 and the curing shrinkage or the like occurs. Even if the stress of (3) acts during the formation of the laminated plate A, the metal foil 3 having a small contraction can prevent the surface of the laminated plate A from contracting and prevent the unevenness of the surface of the laminated plate A from occurring. . FIG. 2 shows another embodiment of the present invention, in which a release sheet 2 is fused and integrated on both sides of a metal foil 3 such as a copper foil. . Therefore, in this product, since one metal foil 3 and two release sheets 2 can be handled as one product, the labor of the work at the time of build-up can be reduced. The method shown in FIGS. 1 and 2 is a multi-stage molding method by a batch operation, but the present invention can be applied as it is even when simultaneously molding a plurality of laminated plates in a continuous molding method. It is a thing.

【Example】

The invention will now be illustrated by the examples. Example 1 As a prepreg, a glass cloth impregnated with an epoxy resin and dried was used. As shown in FIG. 1, six prepregs were overlaid, and a release sheet of a triacetate film was overlaid on each of the six prepregs. 28 through copper foil as a set
Stacked. Then, this was sandwiched between the upper and lower metal plates and built up as a single step in a press machine, and heat and pressure molding was performed to obtain 28 unclad laminated plates per step. Example 2 As shown in FIG. 2, Example 1 was repeated except that a copper foil was fused with a triacetate film on both sides.
An unclad laminate was obtained in the same manner as in. Comparative Example 1 Six prepregs were overlaid, and release sheets of triacetate film were overlaid on the top and bottom of the six prepregs.
As shown in the figure, sandwiching between metal plates, stacking 14 sets per stage as a set, building up this in a press machine and performing heat press molding, 14 unclad laminated plates per stage Got Comparative Example 2 Six prepregs were piled up, and a set of 28 prepregs was stacked via a release sheet of a triacetate film. Then, it was sandwiched between the upper and lower metal plates and built up as a single stage in a press machine, and heat and pressure molding was carried out to obtain 28 unclad laminated plates per stage. In each of Examples 1 and 2 and Comparative Examples 1 and 2, the working time required from the build-up of the prepreg to the pressing of the laminate through the press was measured, and the obtained laminate had no surface irregularity. I did a test. The results are shown in the table below. As can be seen from the results in the table, in each of the examples, the working time was short and the productivity was excellent, and it was possible to prevent unevenness from being generated on the surface of the laminated plate.

【The invention's effect】

As described above, in the present invention, a plurality of prepregs are superposed and release sheets are superposed on the upper and lower sides of the superposed prepregs to form one set, and a plurality of sets are provided via a metal foil between each set. Since they are stacked and sandwiched between the metal plates for heat and pressure molding, it is of course possible to manufacture a plurality of laminated plates between the metal plates with good productivity. Even if stress such as curing shrinkage acts on the laminate when it is in contact with the foil, the shrinkage of the surface of the laminate can be prevented by the metal foil with small shrinkage, and unevenness occurs on the surface of the laminate. Can be prevented.

[Brief description of drawings]

1 and 2 are schematic exploded views showing a method of the present invention, and FIGS. 3 and 4 are schematic exploded views showing a conventional method. Reference numeral 1 is a prepreg, 2 is a release sheet, 3 is a metal foil, and 4 is a metal plate.

Claims (1)

[Claims] 1. A plurality of prepregs are superposed on each other, and release sheets are superposed on and under the superposed prepregs to form one set, and a plurality of sets are superposed with a metal foil interposed between the sets.
A method for producing a laminated plate, which comprises sandwiching this between metal plates and subjecting it to heat and pressure molding.