JPS5833456A - Manufacture of metallic foil lined laminated board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

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

There are the following methods for producing metal foil-clad laminates, particularly copper-clad laminates using copper foil as the metal foil. That is, unsaturated polyester resin, diallyl phthalate prepolymer, vinyl ester resin, l,2-polybutadiene, and other resins having unsaturated bonds are diluted with vinyl monomer as necessary, and a polymerization initiator is further added to make the unsaturated resin. A resin-impregnated base material, which will become the substrate for the copper-clad laminate, is created by creating a fest and impregnating the base material with it. Next, there is a method in which a plurality of resin-impregnated base materials are stacked, and then a copper foil coated with an adhesive is stacked and laminated by passing the stack through a roll, and then heated under no pressure to produce a copper-clad laminate. This method does not involve placing layers of adhesive-coated copper foil and resin-impregnated base material in a press machine and heat-pressing them, but instead produces copper-clad laminates by heating them without pressure. , continuous production is possible, and a vinyl monomer serving as a crosslinking agent can be used to dilute the unsaturated resin without using a solvent, so it is effective from the point of view of resource saving. However, if the adhesive used in the production of copper-clad laminates (epoxy, phenol, etc.) is used as the adhesive for the adhesive-coated copper foil, the beer strength of the resulting laminate may be insufficient. This caused a problem in that the strength of the beer, particularly in the heated state, became weak and peeling occurred between the substrate and the adhesive layer. Therefore, it was considered to use vinyl ester resin as the adhesive applied to the copper foil.

Vinyl ester resin reacts with the unsaturated resin in the resin-impregnated base material, so it exhibits strong adhesion to the substrate. However, when the vinyl ester resin is in the A-stage state, when stacking it on the resin-impregnated base material, a mixing phenomenon occurs between the vinyl ester resin and the impregnating resin of the resin-impregnated base material, and the vinyl ester resin is diluted. The beer strength of the copper foil of the laminate had decreased. On the other hand, if the vinyl ester resin is cured too much, the reaction between the resin-impregnated base material and the impregnated resin becomes difficult to occur, resulting in the problem of peeling from between the substrate and the adhesive layer. Therefore, in order to prevent such problems from occurring, it is necessary to apply the vinyl ester resin to the copper foil and then bring it into a moderately one-stage state. One way to achieve this B-stage is to apply an adhesive to the copper foil and dry it, but this method is disadvantageous in terms of resource conservation because the crosslinking agent evaporates during drying. There are also problems with the recovery of volatile matter.

Moreover, a drying oven is required for drying, which creates the problem of a long production line in the case of continuous production.

Therefore, the inventors conducted research to find a method that can bring vinyl ester resin to a moderately one-stage state without causing the above-mentioned problems. As a result, when a photopolymerization initiator is blended with a thermal polymerization initiator in vinyl ester resin, and this is applied to copper foil and then irradiated with ultraviolet rays, the vinyl ester resin becomes moderately one-stage, which causes the problems described above. We found that this no longer occurs. Then, when this twisted-staged copper foil with vinyl ester resin is layered on the resin-impregnated base material and heated, the vinyl ester resin of the copper foil is completely cured, and the impregnated resin of the resin-impregnated base material is hardened, and the copper foil is heated. This makes it possible to obtain stretched laminates.

That is, the present invention is a method for manufacturing a metal foil-clad laminate by laminating an unsaturated resin-impregnated base material and a metal foil through an adhesive layer and curing them by heating, wherein the adhesive layer is photopolymerized. The gist is that the vinyl ester resin adhesive layer containing an initiator and a thermal polymerization initiator is B-staged vinyl ester resin adhesive layer obtained by irradiating light to form B-sf-silyl. be.

The vinyl ester resin used for adhesion in this invention is a resin obtained by reacting an epoxy resin and an unsaturated carboxylic acid, and is a crosslinking monomer (styrene, diallyl phthalate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, hydroxyethyl methacrylate, etc.). This material has photocurability.

Examples of the photopolymerization initiator contained in the vinyl ester resin include benzoin, benzoin methyl ether, benzoin ethyl ether, pe/twin isopropyl ether, benzophenone, and dibenzylanthracene.
It is usually used at a ratio of o, 2 to 5 PHR.

As the thermal polymerization initiator contained in the vinyl ester resin together with the photopolymerization initiator, common organic peroxides such as benzoyl peroxide, [-butyl perbenzoate, cumene hydroperoxide, dicumyl peroxide, methyl ethyl ketone peroxide, etc. etc., usually 0
．． Used at a rate of 2-2 PHR. The thermal polymerization initiator is used to form a B-staged vinyl ester resin adhesive layer by overlaying the metal foil of the vinyl ester resin layer skeleton on a resin-impregnated base material and then heating it. It has the effect of completely curing. In addition,
Vinyl ester resin is light above.

In addition to the thermal polymerization initiator, inorganic or organic fillers may be added as necessary.

The resin-impregnated base material that serves as the substrate for metal foil-clad laminates is:
Unsaturated polyester resin for base materials such as kraft paper, linter paper, glass cloth, glass nonwoven fabric, etc.

It is made by diluting an unsaturated resin such as diallyl phthalate prepolymer, vinyl ester l fat, 1,2-polybutadiene, etc. with styrene, diallyl phthalate, acrylic monomer, etc. as necessary, and further containing a polymerization initiator. A material impregnated with unsaturated polyester resin is used.

Further, examples of the metal foil include copper foil, aluminum foil, stainless steel foil, etc., but copper foil is usually used.

The metal foil-clad laminate according to the present invention is manufactured, for example, as follows. That is, a layer of vinyl ester resin containing a photopolymerization initiator and a thermal polymerization initiator is applied to the metal foil. The coating thickness is preferably set to 20 to 200 microns. If the adhesive strength is below the above range, sufficient adhesive strength cannot be obtained, and even if the adhesive strength is above the above range, no further improvement in strength will be observed and instead warping will occur. Next, the vinyl ester resin coating layer is irradiated with ultraviolet rays to B-stage it. Examples of the ultraviolet irradiation device include high-pressure and low-pressure mercury lamps and chemical lamps. The amount of ultraviolet irradiation varies depending on the type of vinyl ester resin, the type of crosslinking agent, the coating thickness, etc., but is preferably set to 200 to 2000 mj/d. That is, it is preferable that the surface of the applied vinyl ester resin remains slightly sticky even after irradiation with ultraviolet rays. If the irradiation is less than 200 mj/d, the degree of B-staging is low and sufficient adhesive strength with the metal foil cannot be obtained.

If it exceeds 2,000 mj/d, B-sulfuric acid formation progresses too much and sufficient adhesive strength with the substrate cannot be obtained. Next, this metal foil with a B-staged vinyl ester resin coating layer is stacked on a predetermined number of resin-impregnated base materials with the coating layer facing downward, and in this state, it is passed through a roll, and then passed under no pressure. Continuous production of metal foil-clad laminates by heating and curing is performed.

Since this invention produces a metal foil-clad laminate in the manner described above, the drying step required to B-stage the vinyl ester resin is not required, and problems caused by volatilization of the crosslinking agent (waste of resources, While avoiding problems such as (b) loss of crosslinking agent, installation of a drying oven, and the accompanying lengthening of the production line, we can produce metal foil-clad laminates that have sufficient beer strength. It can be manufactured continuously.

Next, examples will be described together with comparative examples.

[Examples 1 to 5. Comparative Examples 1 and 2 Five sheets of kraft paper (TO-10, manufactured by Tokai Valve) were each impregnated with an unsaturated polyester resin (FG-104, manufactured by Inu Nippon Ink) containing 1WE% benzoyl peroxide. On the other hand, an adhesive having the composition shown in the table below was applied to a copper foil having a thickness of 85 μm, dried, and then laminated with the above-mentioned impregnated paper through a roll. Then, it was heated and cured in a dryer at 120°C for 15 minutes to obtain a copper-clad laminate. For drying, an 80W/c11 high-pressure mercury lamp (manufactured by Oak Manufacturing Co., Ltd.) was used. Further, the coating thickness of the adhesive was set to 60 to 70 μm.

The normal state and 100% of the copper-clad laminate thus obtained
The beer strength at °C was measured and shown in the following table. From the table, it can be seen that the beer strength of the copper-clad laminates of Examples is superior to that of Comparative Examples.

(Hereafter, the rest is white)

Claims (2)

[Claims] (1) A method of manufacturing a metal foil-clad laminate by laminating an unsaturated resin-impregnated base material and metal foil with -C through an adhesive layer and curing with heat, wherein the adhesive layer contains a photopolymerization initiator. A method for manufacturing a metal foil-clad laminate, characterized in that the vinyl ester resin adhesive layer containing a thermal polymerization initiator is B-staged by irradiating light onto the vinyl ester resin adhesive layer. (2) The unsaturated resin of the unsaturated resin-impregnated base material is unsaturated polyester resin, diallylphthalate prepolymer,
The method for producing a metal foil-clad laminate according to claim 1, wherein the resin is at least one resin selected from the group consisting of vinyl ester resin and 1,2-polybutadiene.