JPH03110160A - Production of laminated sheet - Google Patents

Abstract

PURPOSE:To make it possible to produce a laminated sheet with excellent high frequency characteristics in a continuous technique by preparing a prepreg in continuous lengths by impregnating a base material with a polyphenylene oxide compsn., laminating this prepreg in layers, performing laminate molding thereof. CONSTITUTION:A polyphenylene oxide compsn. is used as a resin for preparing a prepreg 1, which is prepd. in continuous lengths. The prepregs 1 are continuously fed through guide rolls 6 and are continuously put in layers by means of laminating rolls 7. While a laminate 5 wherein the prepregs 1 and if necessary, a metal foil 10 are put in layers is continuously transferred, it is preheated and continuously introduced in a double belt 2. The laminate 5 is passed through the double belt 2, heat-pressed by means of press-heating apparatus 11 between upper and lower endless belts 3 and 4 and cut by means of a cutter 13 to obtain a laminated sheet A with a specified dimension.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for manufacturing a laminated board used as a printed wiring board by a continuous method.

[Conventional technology]

Laminated boards are usually prepared by preparing prepreg by using paper or glass cloth as a base material and impregnating it with a thermosetting resin and drying it, and then cutting this prepreg into a predetermined size, and then cutting the prepreg into a plurality of pieces cut into the specified size. Layering sheets of prepreg and, if necessary, metal foil such as copper foil, setting these in a press machine in a stack of 10 to 141 ff via plates, and performing multi-stage lamination molding by heating and pressing for a predetermined period of time using upper and lower heating plates. Manufactured by. However, when a laminate is manufactured by multi-stage lamination molding in this way, the work efficiency is poor due to patch work, and there are many problems in productivity. For this purpose, the present applicant has proposed a method of manufacturing a laminate using a continuous method, such as in Japanese Patent Laid-Open No. 189439/1983. In other words, multiple sheets of long prepreg are piled up and continuously fed, and if necessary, a long metal foil is piled up, and this is continuously passed through a double belt and heated and pressurized by the double belt. ,
This allows the laminated plates to be formed continuously. According to this method, since the laminate is manufactured through continuous molding operations, production efficiency is dramatically improved compared to multi-stage lamination molding performed in batch operations.

[Problem to be solved by the invention]

On the other hand, the frequencies used in fields such as the electronics industry, communications, and computers are being shifted to high-frequency regions, and printed wiring board laminates used in such high-frequency regions are designed to shorten signal propagation delays. Moreover, a smaller dielectric constant is required. For this reason, in order to obtain such a laminate with excellent high frequency characteristics, a resin constituting the laminate, that is, a prepreg resin, which has excellent frequency characteristics, such as a patent application published in 1988-5004, has been developed.
Aromatic polyisocyanates such as No. 34 have been used, but resins with excellent high frequency properties are generally used at high temperatures (250 to 300°C in some cases) for long periods of time (
In some cases, it may be necessary to perform molding for 1 to 2 hours. However, when the prepreg is continuously passed through a double belt and molded under heat and pressure, it is impossible to sustain the molding for a long time at high temperatures. It is not possible to manufacture laminates using a continuous method using double belts (as described above), and the current situation is that it is difficult to manufacture laminates with excellent high frequency characteristics using a continuous method. be. 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 manufacturing a laminate that can manufacture a laminate with excellent high frequency characteristics by a continuous method.

[Means to solve the problem]

In the method for manufacturing a laminate according to the present invention, a long prepreg 1 is prepared by impregnating a base material with a polyphenylene oxide composition, and while continuously feeding the long prepreg 1, a required number of prepregs 1, 1... are stacked one on top of the other, and this is continuously fed into the double belt 2 to form a laminated layer. The present invention will be explained in detail below. The prepreg 1 is prepared as a long prepreg by impregnating a base material with a resin varnish and drying it. As this base material, paper, glass #I & miscellaneous woven fabric or non-woven fabric, 77 resin cloth, fluororesin porous sheet, etc. can be used. Further, in the present invention, a polyphenylene oxide composition is used as the resin used for preparing the prepreg 1. As this polyphenylene oxide composition, it is preferable to use a thermosetting polyphenylene oxide such as that provided in JP-A-63-25035. It is formed by blending a crosslinkable polymer and/or a crosslinkable monomer, an initiator, and, if necessary, a flame retardant and an inorganic filler. PPO is, for example, represented by the following general formula, R (R is hydrogen or a hydrocarbon group having 1 to 3 carbon atoms, and each R may be the same or different). Examples include poly(2,6-nomethyl-1,4-phenylene oxide). Examples of the crosslinkable polymer include 1,2-polybutadiene, 1t4-polybutadiene, styrene-butadiene copolymer, modified 1,2-polybutadiene such as maleic modification, acrylic modification, and epoxy modification, rubbers, etc. These can be used alone or in combination of two or more. Examples of crosslinking monomers include acrylic acids such as ester acrylates, urethane acrylates, ether acrylates, melamine acrylates, alkyd acrylates, and silicone acrylates, triallyl cyanurate, triallyl isocyanurate, and ethylene glycol dichloride. Examples include polyfunctional monomers such as methacrylate, divinylbenzene, and noaryl athalate, monofunctional monomers such as vinyltoluene, ethylvinylbenzene, -styrene, and paramethylstyrene, and other polyfunctional epoxies. These can be used alone or in combination of two or more. Examples of the polymerization initiator include dicumyl peroxide, tert-butylcumyl peroxide, and dicumyl peroxide.
t-Butyl peroxide, 2,5-dimethyl-2,5
-no(tert-butylperoxy)hexyne-3,
Examples include peroxides such as 2,5-dimethyl-2,5-c(Lert-butylperoxy)hexane and a,a-bis(tert-butylperoxy-isopropyl)benzene. They can be used alone or in combination of two or more. The blending ratio of the PPo composition is such that PPO is 10 to 90 parts by weight, and the total amount of crosslinkable polymer and crosslinkable monomer is 1 to 50 parts by weight.
The initiator is preferably 0.1 to 5 parts by weight, 35 parts by weight or less when a flame retardant is used, and 100 parts by weight or less when an inorganic filler is used. Further, it is preferable that the weight ratio of the crosslinkable polymer and the crosslinkable monomer is set to be crosslinkable polymer/crosslinkable monomer≦20. Then, prepreg 1 can be created by impregnating the base material with 7 varnish of the PPo composition prepared as described above and heating and drying it.As shown in FIG. 1 is unwound from a roll and a predetermined number of prepregs are continuously fed through an idle roll 6, and each prepreg 1 is continuously overlapped by a stacking roll 7. On the other hand, metal M10 such as copper foil is also formed into a long length and wound into a roll, and this is unwound to form a double-sided metal foil clad laminate that is superimposed on the outer surface of the outermost layer of the above-mentioned stacked prepregs 1. When manufacturing, two pieces of metal 1! The same amount of outer layer of prepreg 1 is layered using FIO, and when producing a single-sided metal foil clad laminate, metal M10 is layered only on one outermost layer, and metal M10 is layered on the other outermost layer. A film such as a 7-layer resin film that can withstand temperatures of 150° C. or higher and has excellent high frequency properties is layered on top. Here, metal! As the material 10, any material can be used, such as a material coated with an adhesive or a foil made of a combination of an aluminum carrier and an ultra-thin copper foil. While continuously feeding the laminate 5 in which a plurality of prepregs 1 and metal foils 10 are piled up as necessary, the laminate 5 is preheated to melt the resin contained in the prepreg 1, and then , the laminate 5 is successively introduced into a double belt 2 constituted by upper and lower endless belts 3.4 which are continuously driven by a drum 9. Preheating is preferably carried out by passing the laminate 5 between the upper and lower high frequency application electrodes 8, 8 and heating it dielectrically under no pressure or under contact pressure. The heat is heated internally rather than on the surface of the prepreg 1, which prevents the surface from being heated to a high temperature and the curing reaction of the resin on the surface of the prepreg 1 to proceed quickly, unlike when external heating is performed using electric heat or the like. It is possible to reduce the occurrence of voids being included in the laminate due to the air bubbles not being able to escape from the prepreg 1 even when pressurized with the double belt 2.Then, the laminate 5 is passed through the double belt 2. In pressurizing the laminate 5 between the upper and lower endless belts 3.4, a pressurizing and heating device 11.11 such as a heating plate is disposed inside each endless belt 3.4. 11, the laminate 5 is heated and pressurized, and the resin of the prepreg 1 is cured, and a plurality of prepregs 1 and metal foil 10 are cured.
This is a method for laminating and bonding. Pressure is 20kg/cwt
It is carried out at a low pressure of about 2 to 30 kg/cm2 or less, and in some cases it may be carried out at a contact pressure. The laminated body thus laminated is continuously drawn out as the double belt 2 is driven, and is led to the idle roller 12 and cut by the cutter 13, thereby cutting the metal foil into a fixed size. It is possible to obtain a laminate A with a high tension. When performing laminated molding using the continuous method as described above,
PPO contained in the prepreg 1 has a low dielectric constant and excellent high frequency properties, and this PPO can be heated at a temperature of 250° C. or less and molded within 30 minutes. Therefore, by using the prepreg 1 prepared by impregnating the base material with this PPO, it is possible to perform laminated molding using the conventional continuous construction method using the double belt 2,
This makes it possible to manufacture a laminate A with high high frequency characteristics.

【Example】

The present invention will be explained in detail below using examples. 70 parts by weight of K1 Chupoly(2,6-dimethyl-114-phenylene oxide), 20 parts by weight of styrene butadiene block copyrimer (Tulbulen T-406 manufactured by Asahi Kasei Corporation), 10 parts by weight of triallylisocyanurate, 2 , 2 parts by weight of 5-methyl-2,5-c(tert-butylperoxy)hexyne-3 (Perhexin 25B manufactured by Nippon Oil & Fats Co., Ltd.) was dissolved in trichlorethylene to give a 20% concentration. A PPO varnish was prepared. Then, a lath woven fabric with a thickness of 0.1 mm was impregnated with this PPO varnish and dried at 50° C. for 10 minutes and at 120° C. for 20 minutes to obtain a prepreg with a resin content of 50% by weight. Next, using this prepreg, a laminate was manufactured using the continuous construction method shown in FIG. That is, prepreg 8
At the same time, copper foils with a thickness of 0°035 mm are placed on top and bottom of the sheets, and heated using a high frequency dielectric heating device with an oscillation frequency of 13.56 MHz to melt the prepreg resin. The material is introduced into a double belt rotating at a high speed, and passed through the double belt for 20 minutes at a pressure of 25 kg/am2 and a temperature of 250°C to form a laminated sheet, and then cut to a predetermined size to form a double-sided copper-clad laminate. I got it. 520 parts by weight of a brominated epoxy resin with an epoxy equivalent of 520, 9 parts by weight of dicyanamide, 2-ethyl-4-
0.5 parts by weight of methylimidazole was added and dissolved in a solvent to obtain an epoxy resin varnish. The del time of this varnish at 160°C was 10 minutes. A prepreg with a resin content of 45% by weight and a gel time of 180°C at 160°C was obtained by impregnating 205 g/2 of this epoxy resin varnish into a glass cloth and drying it. This prepreg is 50011II11×500
Cut to a fixed size of 11Im, stack 8 sheets, layer copper foil with a thickness of 0.035mm above and below, sandwich this between 1.5mm thick stainless steel plates, and heat the plate of a multi-stage hydraulic press. Insert between the two and heat at 170℃ for 25
By performing multi-stage lamination molding by heating and pressing for minutes, a laminate plate with copper cladding on both sides was obtained. Regarding the laminates obtained in the above examples and comparative examples, JIS
The dielectric constant was measured based on C6481. In addition, it was measured how many laminates could be manufactured in the example within the time required to manufacture 100 laminates in the comparative example. These results are shown in the table below. As seen in the results in the table, P as the prepreg resin
It is confirmed that the example using PO has a low dielectric constant and excellent high frequency characteristics. It is also confirmed that the continuous production method has high production efficiency.

【Effect of the invention】

As described above, in the present invention, a long prepreg is prepared by impregnating a base material with a polyphenylene oxide composition, and the required number of prepregs are stacked while continuously feeding the long prepreg, Since this was continuously fed into a double belt and laminated to form, the poly-177-22lene oxide that makes up the prepreg has a low dielectric constant and excellent high frequency properties, and polyphenylene oxide has a relatively low dielectric constant. It is possible to form a laminate in a short time by heating it at a high temperature, and it is possible to form a laminate with high high frequency characteristics by using the conventional continuous method. It is something that can be manufactured.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the apparatus used in the present invention, in which 1 is a prepreg, 2 is a double belt, and A is a laminate.

Claims (1)

[Claims] (1) A long prepreg is prepared by impregnating a base material with a polyphenylene oxide composition, and the required number of prepregs are overlapped while continuously feeding this long prepreg, and this is continuously attached to a double belt. A method for manufacturing a laminate, characterized by feeding and laminating forming.