JPS6290235A - Electric 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] Shut off! The present invention relates to a metal foil-clad synthetic resin laminate used as a printed circuit board.

'and. One of the important properties required of metal foil-clad laminates for printed circuit boards is the adhesive strength (peel strength) of the metal foil.

The adhesive strength of metal foil mainly depends on the adhesive used.
Epoxy adhesives, epoxy acrylate adhesives, polyvinyl butyral/phenol adhesives, nitrile rubber/phenol adhesives, etc. are used, but the present inventors
838. In the continuous method as proposed in 56-98136, etc., epoxy adhesives, especially amine-curable epoxy adhesives, are suitable. Amine curing agents can be broadly classified into aromatic polyamines, alicyclic polyamines, aliphatic amines, and polyamide amines, but aromatic polyamines have the disadvantage of becoming colored over time. Alicyclic polyamines are not colored (and have excellent heat resistance, but are generally brittle,
Poor adhesion to metal foil. Aliphatic amines and polyamide amines have drawbacks such as poor heat resistance.

Therefore, it is an object of the present invention to improve the above-mentioned drawbacks of adhesives used in metal foil-clad laminates.

The present invention provides a metal foil-clad laminate for electrical use having a plurality of base layers impregnated with a curable resin and a metal foil laminated on at least one side of the base layer with an adhesive, the adhesive being an alicyclic laminate. The present invention provides a metal foil-clad laminate for electrical use, characterized in that it is an epoxy adhesive that uses a mixture of a group polyamine and dimethylaminopropylamine as a curing agent.

The metal foil-clad laminate of the present invention has excellent adhesive strength of the metal foil at room temperature and high temperature, and the adhesive layer is less likely to discolor over time.

The laminate of the present invention can also be manufactured by the conventional method of the Hutch method, but the present inventors have previously reported
8. It is preferable to manufacture by the continuous method proposed in 56-98136 and the like. These continuous methods use curable resins that are liquid at room temperature and do not generate volatile by-products during curing. Such curable resins include epoxy resins and unsaturated resins. The unsaturated resin refers to one in which the resin before curing contains a double bond unsaturated group capable of radical polymerization and is cured by a radical polymerization reaction of the unsaturated group. Unsaturated polyester is a typical example, but other examples include epoxy acrylate resin, polyester acrylate resin, urethane acrylate resin, spiran resin, and diallyl phthalate resin.

Curable resins can be made flame retardant by containing halogen atoms, especially bromine, bonded to their skeleton.

Flame retardation can also be achieved by adding additive halogenated flame retardants to halogen-free resins.

As a base material, kraft paper, linter paper, etc./L10
Any conventionally known materials can be used, such as glass fiber base materials such as glass cloth, glass cloak, glass paper, glass paper mixed with cellulose, and synthetic fiber cloth.

The metal foil used in the present invention includes electrolytic copper foil, rolled copper foil,
There are aluminum foils, etc., but electrolytic copper foils are the most common.

In the present invention, the adhesive for bonding the metal foil is an epoxy adhesive containing an epoxy resin and the above-mentioned curing agent. Epoxy resins are obtained by reacting bisphenol A, bisphenol S, bisphenol F1 various novolak type phenol resin initial condensates, etc. with epichlorohydrin. Either type can be used alone or in combination.

The curing agent is a mixture of alicyclic polyamine and dimethylaminopropylamine as described above. Specific examples of alicyclic polyamines include isophorone diamine, 1,3-bisaminomethylcyclohexane, menthanediamine, bis-(4-aminocyclohexyl)-methane, bis-(
Examples include 4-amino-3-methylcyclohexyl)-methane.

The mixing ratio of alicyclic polyamine and dimethylaminopropylamine is suitably within the range of 95:5 to 50:50, preferably 90:10 to 65:35 in terms of molar ratio. If the proportion of alicyclic polyamine is high, the adhesive strength at room temperature will be low, and on the other hand, if the proportion of dimethylaminopropylamine is high, the adhesive strength at high temperature will be low, and the pot life of the composition will be shortened.

Diethylaminopropylamine, a similar amine, had no synergistic effect when used in combination with alicyclic polyamine.

To reduce toxicity or control pot life or curing time, alicyclic polyamines and/or dimethylaminopropyl amines can be reacted with epoxy resins, acrylonitrile, ethylene glycol, etc. to modify some of the active hydrogens of the amines. It may also be used.

The amount of the amine curing agent used is approximately equivalent to the epoxy equivalent of the epoxy resin.

The epoxy resin adhesive used in the present invention contains pigments,
It may contain conventional additives such as fillers, accelerators, rubbers, solvents, etc.

The process of manufacturing the metal foil-clad laminate of the present invention by a continuous method involves continuously unrolling a plurality of base materials from a roll,
They are individually impregnated with a curable resin liquid, the resin-impregnated base materials are combined, and a metal foil coated with the above-mentioned adhesive composition is continuously laminated on one or both sides of the combined base materials. This includes the steps of curing the material and cutting it to a predetermined size. A cover sheet such as a polyester film is laminated on the side that is not laminated with metal foil, and is peeled off after curing. Curing is generally carried out by passing the resin continuously through a tunnel-type curing furnace, but in the case of unsaturated resins, it can be cured by light, electron beams, radiation, etc. as long as the cover sheet allows the passage of the resin. It is also possible to do this in part or in full.

Examples of the present invention are shown below.

Examples and Comparative Examples Eight sheets of glass cloth (Nittobo WE-18K) were continuously unrolled from a roll, and a commercially available unsaturated polyester resin (Narita Pharmaceutical Co., Ltd., Polymer 6311) was individually applied to them.
A 35 μm thick copper foil impregnated with a resin solution consisting of 100 parts by weight and 1 part of benzoyl peroxide, combined, and coated with an epoxy adhesive is continuously laminated, and a polyester film is attached to the opposite side as a cover sheet. was laminated, cured for 20 minutes at 100°C in a curing oven, peeled off the cover sheet, cut, and post-cured at 160°C for 20 minutes to obtain a single-sided copper foil-clad laminate with a thickness of 1.6 mm. .

The epoxy adhesive consists of a bisphenol A epoxy resin (Epikoat 827, manufactured by Yuka Shell Epoxy) and a hardening agent. The composition of the hardening agent is shown in Table 1, and the composition of the adhesive is shown in Table 2. has been done.

Copper foil peeling strength (2
0°C and 150°C) are shown in Table 2.

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Claims (2)

[Claims] (1) In an electrical metal foil-clad laminate having multiple base material layers impregnated with a curable resin and a metal foil laminated on at least one side of the base material through an adhesive, the adhesive is an alicyclic polyamine. A metal foil-clad laminate for electrical use, characterized in that it is an epoxy adhesive whose curing agent is a mixture with dimethylaminopropylamine. (2) The electrical metal foil-clad laminate according to item 1, wherein the curable resin is an unsaturated resin.