| 摘要 |
PURPOSE:The title laminate excellent in moisture resistance and soldering-heat resistance upon absorption of moisture, prepared by impregnation with an epoxy resin composition obtained by reacting a novolak epoxy resin with a bisphenol epoxy resin and bisphenol A. CONSTITUTION:An epoxy resin varnish is obtained by dissolving an epoxy resin composition obtained by reacting 5-20wt% novolak epoxy resin of an epoxy equivalent weight of 170-230g/eq. with a bisphenol A epoxy resin of an epoxy equivalent weight of 180-190g/eq. and bisphenol A in the presence of a basic catalyst (e.g., NaOH), a curing agent and a cure accelerator in a solvent. The necessary number of tack-free prepregs obtained by impregnating glass fiber cloth with said varnish and heating the impregnated cloth are laminat ed with copper foils, and the assemblage is heated under pressure.
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