JPH0411376B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously manufacturing a laminate having a rubber-modified resin (hereinafter referred to as adhesive) layer on one or both surfaces.

Such laminates are attracting attention mainly as additive laminates.

Conventional laminates for additives were published in Japanese Patent Application Publication No. 1983-1989.
18571, as shown in Japanese Unexamined Patent Publication No. 15876, etc.
A prepreg is made in advance by heating and semi-curing a base material such as paper or glass that is impregnated with a phenol resin or epoxy resin, and then multiple sheets of prepreg are layered with adhesive coated on one or both surfaces. Alternatively, a separately prepared adhesive film was laminated on the surface of a plurality of prepregs, and was manufactured by heating and pressurizing.

Alternatively, as described in Example 1 of JP-A-58-8597, an adhesive can be applied to the surface of an already cured laminate, and only this adhesive layer can be further heated and cured later to produce an additive laminate. It is said that

Since these are not manufactured consistently from the initial resin impregnation, they require a lot of labor such as batching processes, are poor in productivity and economy, and have insufficient adhesion between the resin and adhesive. It had the following drawbacks.

The present invention solves the problems of these conventional methods. In other words, the present invention involves laminating a plurality of base materials impregnated with a liquid thermosetting resin without going through prepreg and bonding them onto a continuous cover film in a continuous production process of a laminate using a wet method in which the resin is cured. Apply an adhesive to the film and heat it in advance to form an adhesive film by semi-curing to a degree of dryness to the touch or more, and then place the cover film on the outside and apply heat to the adhesive film. After laminating and curing on one or both surfaces of a thermosetting resin-impregnated base material laminate, the film is peeled off to transfer the adhesive to the laminate side and obtain a cured laminate. do.

Examples of the rubber modified resin, that is, the rubber component in the adhesive, include diene copolymers such as nitrile-butadiene copolymers, end-carboxylated nitrile-butadiene copolymers, styrene-butadiene copolymers, and nitrile-butadiene-styrene copolymers. Union,
Examples include graft copolymers.

Resin components to be mixed with this rubber component include phenol resins, epoxy resins, unsaturated polyester resins, etc., and solvents for dissolving both of these components include ketone compounds, aromatic compounds, and mixtures thereof. Good ones are selected. The degree of semi-curing of the adhesive may be such that the solvent is removed, but it may be dry to the touch or B stage.

The cover film is PET, vinylidene fluoride,
It is preferable to use a material such as polyimide that can withstand conditions such as heating during curing of adhesives and thermosetting resins, and that has good releasability from the cured adhesive.

Adhesives and thermosetting resins are generally cured by heat in the presence of a catalyst, but they can also be cured by light or radiation, so in that case a resin corresponding to this is selected.

As the base material, kraft paper made of cellulose fibers, linter paper, synthetic paper made of synthetic fibers, synthetic fiber cloth, glass paper made of glass fibers, glass mat, glass cloth, mixed paper selected from these various fibers, etc. are used.

The thermosetting resin to be impregnated into the base material is preferably one that does not produce reaction by-products such as water or carbon dioxide during curing, and examples thereof include unsaturated polyester resins, epoxy resins, vinyl ester resins, and the like. In particular, when the resin itself is uncured and liquid at room temperature, the base material may be continuously impregnated with the resin, as disclosed in Japanese Patent Application Laid-open No. 144151/1983 filed by the same applicant as the present invention. This is the most preferred embodiment because it can be easily carried out by laminating, continuously overlapping cover films, and curing continuously under substantially no pressure conditions.

In this manufacturing method, an adhesive is applied onto a continuously moving cover film and exposed to heat or light.
After semi-curing with means such as electron beams, a cover film having the above-mentioned semi-cured adhesive layer is laminated on one or both surfaces of a laminate in which a plurality of resin-impregnated base materials are laminated, and then cured together. It becomes possible to continuously produce a good electrical laminate having a rubber-modified resin layer on one or both sides of the laminate, particularly a laminate suitable for additive use.

In addition, when laminating a cover film with an adhesive layer on only one side of the laminate, a cover film or metal foil without adhesive is laminated on the other side to protect the surface of the laminate and cure the resin with peroxide, etc. This accelerates curing by eliminating oxygen and preventing volatilization of the crosslinking vinyl compound.

An example of implementation is shown below.

Example 1 Unsaturated polyester resin using maleic acid, isophthalic acid and ethylene glycol as raw materials
To 100 parts, 2 parts of cumene hydroperoxide and 0.01 part of cobalt naphthenate were added to obtain a resin liquid having a viscosity of 5 poise at 25°C.
The following steps were carried out continuously using an apparatus as shown in FIG.

On the other hand, NBR/phenol adhesive (MEK solution consisting of 45 parts of Nitzpol 1072 and 55 parts of resol-type phenol with a viscosity of 5 poise) was applied onto a PET film (100 μm) using a flow coater and heated to 100°C.
The adhesive was precured for 10 minutes to obtain an adhesive coating film of about 30 μm that was dry to the touch.

Six sheets of long paper with a density of 0.53 g/cm ³ are impregnated with the above-mentioned 5 poise unsaturated polyester resin liquid and laminated, and the PET film with the adhesive coating is laminated on one side with the adhesive coating on the inside, A PET film without adhesive was laminated on the remaining side, and after curing both by heating at 140°C for 15 minutes, the PET film was peeled off from the laminate, and a laminate with adhesive was continuously manufactured efficiently.

This adhesive layer also has good adhesion to the laminate, and is applied to a chromic acid-sulfuric acid mixed acid aqueous solution (specific gravity 1.38) at 55℃ for 2 hours.
A uniform and clean roughened surface was obtained by minute immersion.

The peel strength of the copper foil after treatment with palladium catalyst (Okuno Pharmaceutical OPC-80), accelerator treatment (Okuno Pharmaceutical OPC-555), and chemical copper plating (Okuno Pharmaceutical OPC-Katsupar) was 2.2 Kg/cm, which was a good result. Obtained. Moreover, the adhesive and the unsaturated polyester surface were bonded together.

Example 2 The same adhesive as in Example 1 was applied onto a cover film, semi-cured, sandwiched between both sides of an unsaturated polyester laminate in a sandwich pattern, and heated and cured in the same manner as in Example 1 to form a laminate with adhesive on both sides. Got the board.

Holes were punched in this material using a punching die, and the material was roughened, catalyzed, and chemically plated in the same manner as in Example 1. As a result, the copper plating on the front and back as well as through-hole areas was uniform and clean. It was done.

[Brief explanation of drawings]

The drawing is a schematic diagram of an example of an apparatus for carrying out the manufacturing method of the present invention. 1 is a heat-resistant film, 2 is an adhesive coater, 3 is an adhesive heating pre-curing process, 4 is a base material unwinding, 5 is an unsaturated polyester coater, 6 is a laminated roll,
7 is a heat curing step, and 8 is a transfer roll.

Claims (1)

[Claims] 1. In a continuous wet manufacturing process for laminates in which a plurality of substrates impregnated with a liquid thermosetting resin are layered and cured by heating, a solution of a rubber-modified resin is applied onto a cover film, and a solution of a rubber-modified resin is applied to the cover film. After removing and curing the semi-cured coating film on at least one side of an uncured laminate consisting of a laminate of multiple base materials impregnated with a liquid thermosetting resin, only the cover film is removed. A continuous manufacturing method for laminates characterized by peeling. 2. Continuous manufacturing method for a laminate according to item 1, in which the base material is paper, glass, or a combination of paper and glass. 3. The method for continuous production of a laminate according to item 1 or 2, wherein the thermosetting resin is an unsaturated polyester resin. 4. The method for continuous production of a laminate according to item 1 or 2, wherein the thermosetting resin is an epoxy resin.