POLYAMIDEIMIDE RESIN, AS WELL AS A COLORLESS AND TRANSPARENT FLEXIBLE METAL-CLAD LAMINATE AND CIRCUIT BOARD OBTAINED THEREFROM

摘要

[Object] To provide a flexible metal-clad laminate having excellent heat resistance, flexibility and low thermal expansion together with sufficient colorless transparency and a flexible printed circuit board using the same. [Constitution] A colorless and transparent flexible metal-clad laminate where metal foil is directly laminated or is laminated via an adhesive layer on at least one side of the polyamideimide resin layer in which cyclohexane tricarboxylic acid anhydride is a main monomer, characterized in that said polyamideimide resin has an inherent viscosity of 0.8 dl/g or more and 2.5 dl/g or less.