JPH0671782B2 - Laminated board manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a laminated board which is processed into a printed wiring board and used.

[Background Art] In the production of laminated plates, a continuous forming method which does not require thermocompression molding using a press machine and has extremely high production efficiency has been attracting attention, and its development and improvement have been actively made.
This continuous molding method is generally the following method, for example.

First, the base material is impregnated with the resin varnish by passing a long base material through the resin varnish tank. Here, a glass cloth is generally used as the substrate, or a glass nonwoven fabric is combined with the glass cloth to form a composite. As the resin varnish, unsaturated polyester resins, diallyl phthalate resins, vinyl ester resins, epoxy acrylate resins and other resins having unsaturated bonds are generally used as vinyl monomers and styrene monomers (crosslinking agents).
Those obtained by diluting with a polymerization initiator and adding a polymerization initiator, epoxy resins, and the like are used. Next, while feeding a plurality of resin-impregnated base materials in this way, they are continuously passed through a slit formed by a pair of squeeze rolls, a plurality of resin-impregnated base materials are overlapped and excess resin is squeezed out. Further, a long metal foil or a protective film (release film) is continuously superposed on both sides or one side of the superposed resin-impregnated base materials by a laminating roll. Copper foil, aluminum foil, or the like is used as the metal foil. Then, the laminated product can be sent to a heating furnace and continuously transferred, the impregnated resin is cured by heating, and further cut into a desired size by a cutter to obtain a laminated plate.

However, in this continuous molding method, there is a problem that the obtained laminated plate is largely warped and twisted,
In particular, when glass cloth is used as the substrate, the laminated plate is largely warped and twisted.

[Object of the Invention] The present invention has been made in view of the above points, and in manufacturing a laminated board using glass cloth as a base material, manufacture of a laminated board capable of reducing warpage and twist. It is intended to provide a method.

DISCLOSURE OF THE INVENTION However, in the method for manufacturing a laminated plate according to the present invention, when a plurality of long base materials impregnated with a resin are superposed and then the resin is cured to manufacture a laminated plate, At least both of the base materials are formed of glass cloth, and the glass cloth is continuously passed through a straightening device formed by arranging a straightening roll whose left and right can move vertically between a pair of parallel rolls. And adjust the left and right ends of the straightening roll up and down to adjust the misalignment of each glass cloth so that the difference in misalignment between the two glass cloths is within 4 mm at the corresponding part. The present invention is described in detail below.

Among the laminated plates obtained by the continuous molding method, the inventors of the present invention investigated the cause of the tendency of warping and twisting of the laminated plate in which the glass cloth was used as the base material. It has an inherent problem that bending is likely to occur greatly, and it is considered that this eye-bending greatly affects warp and twist of the laminated plate. That is, the glass cloth is formed by weaving warp yarns parallel to the longitudinal direction and weft yarns orthogonal to the warp yarns. With the glass cloth, the weft yarns are curved so that the weft yarns are curved in the longitudinal direction. Bending is likely to occur. And a pair of glass cloths used as the base material positioned on the outer side of both of the base materials to be piled up 1,
2, one glass cloth 1 as shown in FIG.
If the difference d in the misalignment between the curved weft yarn 1a and the curved weft yarn 2a of the other glass cloth 2 is large, the symmetry of the layer structure of the laminated plate is greatly deviated and Large warpage and twisting will occur. The present invention has been completed based on such knowledge, and the difference d in misalignment is 4 within a range of 250 mm × 250 mm of the glass cloths 1 and 2 used as both outer side base materials among the base materials to be laminated.
The laminate is adjusted to have a thickness of less than or equal to mm so that the laminated plate is manufactured by a continuous molding method.

All of the base materials used for a plurality of sheets may be formed of glass cloth, but a part of the base material is formed of glass paper (glass nonwoven fabric) and only the outer side base materials are formed of glass cloth. You may make it the composite structure which was made. In the case of a composite structure, the laminated plate is likely to be warped or twisted. Therefore, the effect can be remarkably obtained by applying the present invention to a composite structure. Further, when the glass cloths 1 and 2 are set in the continuous forming step of the laminated plate, the difference d in misalignment can be reduced by aligning the directions of the bending of the glass cloths 1 and 2 with each other. During the process, it is preferable to provide the eye-bending correction device 3 to correct the eye-bending of the glass cloths 1 and 2 to reduce the difference d between the eye misalignments. As shown in FIG. 1, the straightening device 3 is formed by providing a straightening roll 5 between a pair of parallel rolls 4, 4 which can be freely moved up and down at the left end and the right end, respectively. When the left and right ends of the straightening roll 5 are moved in the vertical direction while continuously feeding the glass cloths 1 and 2 with 4 and 4, the glass cloths 1 and 2 have a right end and a left end in the width direction. Different tensions can be applied to each of them, and the bending direction and the amount thereof can be adjusted by this tension. In this operation, the bending of the eye on the side opposite to the side where the tension is applied progresses, and by utilizing this in reverse, the eye bending can be corrected and the difference d in the misalignment can be reduced. In this way, the laminated plate is obtained by performing continuous molding in a state in which the difference d in the misalignment between the glass cloths 1 and 2 is controlled to a small numerical value of 4 mm or less.

Next, the present invention will be described with reference to examples.

Examples 1 to 4, Comparative Examples 1 and 2 100 parts by weight of vinyl ester resin (R-806DA manufactured by Showa High Polymer Co., Ltd.) was mixed with 1 part by weight of cumene hydroperoxide, and styrene was further added to give a viscosity of 5 poises ( twenty five
℃) resin varnish is prepared, and this resin is made of two long glass cloth base materials (Nitto Boseki Co., Ltd .: WE-18-BS) and three long glass paper base materials (Japan Vilene Co., Ltd.). Company made: EP-4035) and impregnated with each other, and while continuously feeding them, stack 3 glass papers and stack glass cloths on both outsides of these glass papers. Elongated 18μ thick electrolytic copper foil on the outside (Furukawa Circuit Foil Co., Ltd .: TSTO)
Were cured by heating at 100 ° C. for 20 minutes, and after-cured at 160 ° C. for 20 minutes to obtain a laminated board for a printed wiring board having a composite structure with a thickness of 1.6 mm.

The laminated plate thus obtained was cut into a size of 250 mm × 250 mm, the copper foil on both sides was removed by etching, and this was heat-treated in an electric oven at 130 ° C for 1 hour and then cooled to prevent warping or twisting. The generation state was measured. Further, the difference in misalignment between the glass cloths serving as both outer layers of this laminated plate material was measured. The results are shown in the table below.

A graph showing the relationship between the misalignment and the warp and twist is as shown in FIG. As a result of the table and the graph of FIG. 3, it is confirmed that the warp and the twist can be reduced when the difference between the misalignments is smaller than 4.0 mm.

[Advantages of the Invention] As described above, according to the present invention, at least both outer side base materials of the plurality of base materials are respectively formed of glass cloth, and the left and right can be vertically moved between a pair of parallel rolls. The glass cloth is continuously fed through the glass cloth to the straightening device formed by arranging the straightening rolls, and the left end and the right end of the straightening roll are vertically adjusted to adjust the difference in misalignment between the two glass cloths. Since the misalignment of each glass cloth is adjusted so that the corresponding part is within 4 mm,
The misalignment of the two glass cloths can be reduced to reduce the deviation of the symmetry of the layered structure of the laminated plate, and the warp and twist of the laminated plate can be reduced. In order to reduce warpage and twist of the laminated plate by keeping the thickness within 4 mm, it is possible to obtain a laminated plate with less warp and twist only by suppressing the misalignment without special treatment to prevent misalignment of the glass cloth. In addition, the glass cloth is passed through a straightening device consisting of rolls and straightening rolls to straighten the glass cloth so that the difference in misalignment between the two glass cloths is within 4 mm. Even when it is supplied and the laminated plate is continuously manufactured, the misalignment of the glass cloth can be continuously adjusted, and the laminated plate having no warp or twist can be mass-produced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a straightening device used in the present invention, FIG. 2 is a front view of a glass cloth showing a difference in misregistration, and FIG. 3 is a difference in misregistration and warp or twist. 3 is a graph showing the relationship of the above, where 1 is a glass cloth, 3 is a straightening device, 4 is a roll, and 5 is a straightening roll.

Claims (1)

[Claims] 1. When manufacturing a laminate by laminating a plurality of long base materials impregnated with a resin and then curing the resin, at least both outer base materials of the plurality of base materials are respectively prepared. Formed with a glass cloth, the glass cloth is continuously fed through the glass cloth to a straightening device formed by arranging a straightening roll whose left and right are vertically movable between a pair of parallel rolls, and the left end portion of the straightening roll and A method for manufacturing a laminated plate, characterized in that the right edge part is vertically adjusted to adjust the misalignment of each glass cloth so that the difference in misalignment between the two glass cloths is within 4 mm at the corresponding part.