JPH06134882A - Production of laminated sheet - Google Patents

Abstract

PURPOSE:To suppress the meandering of a base material at the time of the coating with a resin and the residual internal stress due to the meandering and the warpage and twist of a laminated sheet caused by the stress in the continuous molding of the laminated sheet under non-pressure heating. CONSTITUTION:An impregnating resin varnish 2 is applied to a supplied base material 1 and resin varnish or a solvent 5 is applied to the guide roll 3 coming into contact with the surface reverse to the coated surface of the base material 1 to reduce the contact resistance with the guide roll 3. Otherwise, an impregnating resin is applied to the supplied base material and, thereafter, the base material is laminated without being brought into contact with the guide roll or the supplied base material is immersed in the resin varnish to be laminated.

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. More specifically, the present invention relates to a method for manufacturing a laminated board for a printed wiring board, which can improve the characteristics of effectively preventing the laminated board from warping or twisting.

[0002]

2. Description of the Related Art Conventionally, electrical and electronic equipment, communication equipment,
Various structures of printed wiring boards are widely used in various fields such as computers. Various improvements and improvements have been made on the laminated board constituting such a printed wiring board in order to improve its characteristics, and the improvement of the manufacturing method is also an important issue.

As a typical manufacturing method used so far, a method of laminating and molding a prepreg obtained by impregnating a base material such as a glass sheet with a resin and a metal foil under pressure and heating is known. Has been. Also, unlike this pressure molding method, a method of heating and laminating without pressure is also known. This latter method is described, for example, in FIG.
As shown in Fig. 1, a required number of substrates (a) such as unrolled long glass cloth, glass mat, paper, etc. are coated and impregnated with resin varnish (a), and then laminated with a laminating roll (c). The metal foil (d) such as the copper foil and the unrolled copper foil is placed on the outermost layer and heated in a heating furnace (e) without pressure,
This is a method in which after further cutting (f), heat treatment is performed in an annealing furnace (g) to obtain a required laminated plate (h).

[0004] This method is characterized in that, as compared with laminating molding by heating and pressing, inclusion of bubbles is suppressed, continuation and automation are easy, energy is saved, and productivity is excellent.

[0005]

However, the continuous laminating method by pressureless heating is a method of continuous running of a long base material despite its excellent characteristics, and thus constitutes a base material. There is a problem that the contact resistance with the guide roll is large due to the twisting of the yarn and the like, and this resistance tends to cause a peculiar meandering in the long base material.

That is, as shown in FIG. 5, after the base material (a) is unwound and supplied, a varnish (a) as a resin liquid is applied to the base material (a) from one side thereof, and the guide roll is applied. Although it is guided by (K) and guided to the laminating roll (C), the application of the resin varnish (A) from this one side is effective in suppressing the inclusion of air bubbles, but it is applied to the base material (A). Due to the contact resistance with the guide roll (K) on the opposite side of the surface, meandering of several mm to several tens of mm occurs. Therefore, conventionally, as shown in FIG. 5, the unwinding position of the base material (a) is adjusted by moving it by a distance corresponding to the positional deviation (D) due to meandering.

However, this adjustment does not essentially eliminate the influence of meandering, and internal stress remains in the base material (a). The warp and twist of the will become large. Therefore, the performance reliability of the printed wiring board laminate is impaired. The present invention has been made in order to eliminate the drawbacks of the conventional method, and is improved in that it is possible to manufacture a high-performance laminated plate by suppressing the meandering of the base material, suppressing warpage and twist. It aims to provide a new way.

[0008]

As a solution to the above problems, the present invention provides a method of laminating and integrally molding a resin-impregnated base material and an outermost metal foil by pressureless heating,
While applying the impregnated resin varnish to the supply substrate, the resin varnish or solvent is applied to the guide roll that contacts the opposite surface of the application surface to reduce the contact resistance with the guide roll. A manufacturing method is provided.

Further, according to the present invention, in a method of integrally laminating a resin-impregnated base material and an outermost metal foil by pressureless heating, after applying the impregnated resin to the supply base material, it is brought into contact with a guide roll. Without laminating, or by immersing the supply base material in the resin varnish, then laminating,
Also provided is a method for producing a laminated plate, characterized in that the surface of the guide roll in the step of impregnating the supply base material with the resin is made of a low contact resistance material.

[0010]

In the method of the present invention, while utilizing the characteristics of the lamination molding by pressureless heating, as described above, 1) the resin varnish or the solvent is applied to the guide roll which is in contact with the surface opposite to the coated surface of the impregnated resin varnish. 2) After applying the impregnated resin varnish, it is laminated on the laminating roll without contact with the guide roll. 3) The resin varnish is applied to the base material on both sides by immersing it in the resin varnish instead of single-sided application. 4) By configuring the surface of the guide roll with a low contact resistance material such as Teflon, the meandering of the base material due to the contact resistance between the base material and the guide roll and the residual internal stress due to the meandering are suppressed.

Therefore, the warp and twist of the laminated plate due to the internal residual stress can be suppressed. Examples will be shown below to describe the method of the present invention in more detail.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1, 2 and 3 of the accompanying drawings show an embodiment of the present invention, which uses resin varnish impregnation and a laminating roll in the pressureless heating laminating process shown in FIG. Each of the steps up to the bonding of a plurality of resin-impregnated base materials is shown.

That is, in the method illustrated in FIG. 1, the resin varnish (2) is applied to the upper surface of the substrate (1) that is unwound and fed, and the resin impregnation is performed by making use of the feature of reducing air bubble inclusion by the one-side application. Done. The resin-impregnated base material (1) is guided by a guide roll (3) and guided to a laminating roll (4) in which a plurality of sheets are superposed and laminated.

In this process, in order to suppress the meandering by reducing the contact resistance between the guide roll (3) on the side opposite to the coating surface and the substrate (1), the coating is applied to the guide roll (3). A resin varnish or solvent (5) is applied from the side opposite to the side. This effectively reduces the contact resistance due to the twisting of the threads forming the base material (1). FIG. 2 shows another example. In this example, the resin varnish (2) to be impregnated in the supply substrate (1) and the resin varnish or solvent (5 1) is applied on the opposite side of FIG.

As described above, the present invention is effective in coating from either the upper or lower surface. FIG. 3 shows still another example. In this example, the feed substrate (1)
After the resin varnish (2) is applied to the laminate, it is guided to the laminating roll (4) as it is without using any guide roll on the opposite surface. By this method, contact resistance due to the guide roll on the surface opposite to the surface coated with the resin varnish and occurrence of meandering of the base material (1) due to this are avoided.

Further, in this method, although not shown, when the guide roll (3) is used, the base material is dipped in a resin varnish, or the surface of the guide roll (3) is made of, for example, Teflon. It is also effective to use a contact resistance material. In any of the above specific examples, meandering of the base material (1) and residual internal stress due to the meandering can be suppressed. Therefore, warpage and twist of the laminated plate can be suppressed.

Of course, as the substrate (1), glass cloth, glass non-woven fabric, synthetic fiber non-woven fabric, paper or any other suitable material for printed wiring boards can be used, and it can be used in the pressureless heating laminating method. Any suitable non-volatile resin varnish can be used. For example, epoxy resin, unsaturated polyester resin, etc. are used. The resin varnish applied to the guide roll (3) may be the same, and the solvent used for these varnishes may be appropriately used.

In any case, as described above, the substrate introduced to the laminating roll (4) by the method shown in FIGS. 1 to 3 is the same as the conventional method shown in FIG. By a process such as laminating, pressureless heating, and annealing, it is processed into a required laminated plate. Manufacturing Example More specifically, a manufacturing example will be described. For example, by the method shown in FIG. 1, a substrate (1) made of a long glass cloth having a width of 1050 mm is unrolled and supplied, and the following composition (part by weight) is added to the upper surface thereof. ); Liquid epoxy resin 100 (Epicoat 828), dicyandiamide 4 benzyldimethylamine 0.2 Reactive diluent 20 (Epicoat GE100) resin varnish (2) was applied.

A diluent was applied to the guide roll (3) on the side opposite to the application surface. 5 of this resin-impregnated base material
The sheets were overlapped with each other, a copper foil was adhered to the outermost layer, and laminated and molded under a pressureless condition at a temperature of 140 to 160 ° C. for 20 minutes in a heating furnace as shown in FIG. 100 this
Cut into 0 mm square and annealed at 140 ° C for 1
Annealing treatment was performed for 0 minutes, 100 ° C., 10 minutes, and 60 ° C. for 10 minutes. A 1000 mm square laminated plate was obtained.

No meandering of the base material (1) occurred during resin impregnation, and warpage or twisting was not recognized in the obtained laminated plate.

[0021]

As described in detail above, the present invention has the following advantages.
In laminating plate molding by pressureless heating, there is no meandering of the base material in the process of resin coating, and warpage or twisting of the laminating plate due to residual internal stress caused by this meandering does not occur. High quality laminated boards can be manufactured.

[Brief description of drawings]

FIG. 1 is a process outline view showing an embodiment of the present invention.

FIG. 2 is a process outline view showing another embodiment.

FIG. 3 is a process outline view showing still another embodiment.

FIG. 4 is a process outline view showing a continuous laminating method by pressureless heating.

FIG. 5 is a process plan view showing meandering according to a conventional method.

[Explanation of symbols]

 1 Base Material 2 Resin Varnish 3 Guide Roll 4 Laminating Roll 5 Resin Varnish or Solvent

Claims (4)

[Claims] 1. A method for laminating and integrally molding a resin-impregnated base material and an outermost metal foil by pressureless heating, wherein an impregnated resin varnish is applied to a supply base material and the surface opposite to the application surface is contacted. A method for producing a laminated board, which comprises applying a resin varnish or a solvent to a guide roll. 2. In a method of integrally laminating a resin-impregnated base material and an outermost metal foil by pressureless heating, after applying an impregnating resin to a supply base material, laminating without contacting a guide roll. A method for manufacturing a laminated board, comprising: 3. A method for integrally laminating a resin-impregnated base material and an outermost layer metal foil by pressureless heating, wherein a supply base material is immersed in a resin varnish and then laminated. Method. 4. In a method of integrally laminating a resin-impregnated base material and an outermost metal foil by pressureless heating, the guide roll surface of the step of impregnating the supply base material with the resin is made of a low contact resistance material. A method for manufacturing a laminated board, comprising: