JPS6092844A - Laminated board for electricity and 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 an epoxy resin electrical laminate mainly made of a glass substrate or a metal foil-clad laminate made of the same and metal foil.

The electrical laminate used in the present invention refers to a laminate used as a substrate or support plate for various electronic components and devices, and the metal foil-clad laminate refers to a printed circuit board covered with metal foil on one or both sides. means.

These electrical laminates using epoxy resin are conventionally made by impregnating a sheet-like base material such as glass cloth, glass paper, or paper with epoxy resin dissolved in a solvent, and semi-curing by heating and removing the solvent. Layer up many sheets of prepared prepreg, overlap metal foil if necessary, and press to approximately 17mm.
It has been molded by heating and pressurizing at a temperature of 0°C and a pressure of about 40 kg/- or more.

In these conventional methods, since the epoxy resin is solid at room temperature, a solvent is used to create the resin face, which inevitably requires prepreg, and energy is required to remove this solvent. Furthermore, dryers and other equipment for solvent recovery were required. In addition, a large amount of equipment and labor was required to laminate the prepregs and heat and harden them using a press. In order to solve these problems, the present inventors first published Japanese Patent Application Laid-Open Nos. 57-13793 and 55
- Manufacture of laminates using thermosetting resins such as 4838, which are liquid at room temperature and which do not substantially generate reaction by-products such as gas or liquid during the curing reaction process, and which are continuously cured under virtually no pressure conditions. disclosed the law. Furthermore, in conventional electrical laminates, epoxysilane or aminosilane has been used as a treatment agent for glass substrates. However, these processing agents do not have sufficient affinity with epoxy resins, and particularly when the curing agent is an acid anhydride type, the affinity is poor. The present inventors have discovered that a laminate with excellent electrical properties can be obtained by using mercaptosilane among various processing agents, leading to the present invention.

In particular, the improvement in moisture resistance according to the present invention is remarkable.

That is, the present invention includes an electrical laminate and a metal foil-clad laminate made by impregnating a glass substrate treated with mercaptosilane with an epoxy resin composition, laminating and curing the same.

Mercaptosilane used as a treatment agent for glass substrates used in the present invention can be expressed as a structural formula, for example, H3CHIC1j2CII2Si (OCH3)3 (
γ-mercaptopropyltrimethoxysilane), and the treatment amount for the glass substrate is, for example, 0.03~
3%.

Preferably 0.05-1.5%, particularly preferably 0.1%
~1.0%. The treatment method is not limited in any way, and ordinary methods such as dipping or spraying can be used.

Examples of the glass substrate include glass cloth and glass paper. Glass-paper mixed paper is also used.

In addition to the above-mentioned glass substrate, a paper substrate may also be used as the substrate. In this case, the paper base material is preferably treated with a paper treatment agent such as melamine.

The epoxy resin referred to in the present invention can be any commercially available resin, but bisphenol A
Preferred are type epoxy resins, novolac type epoxy resins, and the like. Further, from the viewpoint of N flammability, those containing halogen are preferable.

Any commercially available halogen-containing epoxy resin used in the present invention can be used, but halogenated bisphenol A epoxy resins, halogenated novolac epoxy resins, dibromoneopentyl alcohol epoxy resins, etc. are particularly suitable. preferable. The halogen here means bromine or chlorine, with bromine being particularly preferred from the viewpoint of flame retardancy. In particular, tetrabromobisphenol A type epoxy resin is preferred.

Of course, it is also possible to mix and use these halogen-containing and non-halogen-containing materials.

A solid composition consisting of an epoxy resin and mainly a curing agent is dissolved in a solvent, impregnated into a glass substrate, dried, and the epoxy resin is semi-cured, followed by press molding as a prepreg. Furthermore, the above-mentioned Japanese Patent Application Laid-open No. 56-1441
．． In the case of continuous production by the pressurized continuous curing method disclosed in No. 51, etc., the solvent was removed by evaporation. It is also possible to use it alone without semi-curing, that is, without forming it into a prepreg.

In the present invention, an epoxy resin composition that is liquid at room temperature is suitable for substantially pressureless continuous curing as disclosed in JP-A-56-98136, and is particularly preferably used.

Since the above-mentioned halogenated epoxy resins are often solid, by pre-mixing them with non-halogenated epoxy resins, such as liquid bisphenol A epoxy resins or liquid novolac epoxy resins, it is possible to eliminate the halogen content of the epoxy resin itself. The content can be adjusted or liquefied.

In addition, in order to make an epoxy resin that is solid or highly viscous at room temperature into a resin composition that is liquid at room temperature and has a viscosity that makes it easy to impregnate the base material without using a solvent, it is necessary to use an acid anhydride curing agent that is liquid at room temperature. Can be dissolved.

A liquid acid anhydride made of an acid anhydride is the acid anhydride itself, which is originally liquid, or a mixture of a solid acid anhydride dissolved or eutectic in a liquid acid anhydride.

For example, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, which are liquid in nature, or a mixture thereof, or these liquid acid anhydrides and hexahydrophthalic anhydride and/or tetrahydroanhydride, which are solid in nature. A liquid eutectic mixture of phthalic acid is used. The liquid curing agent made of these acid anhydrides may contain additives such as a curing accelerator.

It is more preferable that these liquid curing agents contain a halogen-containing acid anhydride from the viewpoint of flame retardancy. In particular, there are eutectic mixtures in which hesodic anhydride, which is a solid chlorine-containing acid anhydride, is eutectic with liquid acid anhydrides such as methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and methylnadic anhydride. Well used. This is because het acid anhydride contains chlorine, which increases the halogen content in the composition, improving flame retardancy and heat resistance, resulting in favorable results. In this case, the ratio of het acid anhydride to liquid acid anhydride is
Although it depends on the specific liquid acid anhydride used, for example, when making a eutectic mixture using methyltetrahydrophthalic anhydride, the ratio of het'anhydride:methyltetrahydrophthalic anhydride is 6:4 to 1:9. General.

The amount of these curing agents used per 100 parts by weight of resin is 40
~110 parts by weight, more preferably 50 to 90 parts by weight.

When the epoxy resin composition is in liquid form, its viscosity is generally from 1 to 30 poise, preferably from 2 to 15 poise, from the viewpoint of impregnating the base material and other factors.

In the case where the purpose is a flammable laminate, the above resin composition may contain a patent application filed in 1982-45, which was filed by the same applicant as the present invention.
Preferably, phosphorus-containing flame retardants and/or antimony compounds are added, as disclosed in US Pat.

In addition to the components described above, the resin composition of the present invention may appropriately contain ordinary additives such as pigments, fillers, curing accelerators such as tertiary amines, internal mold release agents, and others. Of course.

To continuously produce electrical laminates or metal foil laminates using the solvent-free liquid epoxy resin composition described above, a glass substrate is impregnated with the composition, and a plurality of impregnated substrates are prepared. The laminate is then laminated, and both surfaces of the laminate are covered with a cover sheet for protection, or in the case of metal foil-clad laminates, one or both sides are covered with metal foil instead of a cover sheet, and the laminate is coated under virtually no pressure conditions. Continuously harden. The degree of curing at this time is small (it can be carried out until the composition becomes non-tacky and has self-shape retention, it can be cured after cutting to practical dimensions, or it can be completely cured continuously). Good too.

For example, the cover sheet has a thickness of 10 to 200 μm.
Various types of release paper, cellophane, synthetic resin films such as Teflon and polyester, or aluminum,
Metal foils such as copper, stainless steel, iron, and phosphor bronze can be used. If necessary, a release agent may be applied to the bonded surface of the cover sheet so that it can be easily peeled off from the laminate after curing.

Examples of the metal foil for cladding include electrolytic copper foil or iron foil, rolled copper foil or iron foil, or aluminum foil. Among these, electrolytic copper foil is common. Since these clad metal foils are integral members that do not peel off even after curing and form a circuit on the product surface, adhesive strength is required. Therefore, it is preferable that the adhesive be applied to the adhesive side of the metal foil.

The electrical laminates and metal foil-clad laminates obtained by the present invention have good electrical properties, especially moisture resistance, water absorption properties, that is, insulation properties after boiling treatment, surface insulation properties after moisture absorption treatment, and volumetric properties. Its resistivity and other characteristics are significantly superior to conventional laminates. Other properties required for electrical laminates, such as heat resistance, mechanical strength, dimensional stability, soldering heat resistance, etc., are all satisfied,
Moreover, it is extremely low in cost, making it possible to provide industrially advantageous products.

EXAMPLES The present invention will be specifically described below with reference to Examples.

Example 1 The following epoxy resin liquid Epicor 1-828 was applied to Nittobo electrical insulation loss ridge-26 which was treated with γ-mercaptobrobyltrino-xysilane so that the adhesion amount was 0.5%.
(Shell Chemical) 100 parts by weight lN-2,200 (Hitachi Chemical) 80 parts by weight N, N-dimethylbenzylamine 1
Part by weight was impregnated, 6 sheets of these were laminated continuously, further laminated with electrolytic copper foil on both sides, continuously cured at 130"C for 20 minutes under virtually no pressure conditions, and then after-heated at 150"C for 1 hour. After curing, a 1.65 mm double-sided copper foil-clad laminate was obtained.

Comparative Example 1 used γ-glycidoxypropyltrimethoxysilane (epoxysilane), and Comparative Example 2 used T-aminopropyltrimethoxysilane (aminosilane) instead of the mercaptosilane in the example.

The performance of the obtained laminate is shown in the table below.

(Margin below)

Claims (1)

[Scope of Claims] (1) An electrical laminate and a metal foil-clad laminate obtained by impregnating a glass substrate treated with mercaptosilane with an epoxy resin composition, laminating and curing the same. (2) The laminate according to claim 1, wherein the curing agent for the epoxy resin is an acid anhydride. (3) The laminate according to claim 1 or 2, which uses an epoxy resin composition that is liquid at room temperature. (4) The laminate according to claim 3, which is cured under substantially no pressure.