| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat-curable insulating adhesive film and a copper-clad heat-curable insulating adhesive film hardly exhibiting change in properties, such as copper foil peeling strength and heat resistance, even when the resin flow changes and having a further prolonged pot life. SOLUTION: This heat-curable insulating adhesive film is prepd. by coating a substrate film with a varnish and evaporating the solvent from it. The varnish contains, as essential ingredients, (A) a high-mol.-wt. epoxy polymer having a film-forming capability, (B) a masked (blocked) isocyanate compd. having at least two isocyanate groups, and (C) an at least difunctional epoxy resin, the wt. ratio of A/C being (100/30)-(100/80). |
