摘要 |
The present invention provides a rigid circuit member obtained by bending a composite laminate comprising a circuit conductor made of a metal foil interposed between plastic films having an elastic modulus of not less than 450 kg/mm2 with an adhesive, characterized in that as said plastic film there is used a polyethylene naphthalate film. The present invention also provides a circuit board adapted to be connected to a conductor on a rigid substrate, characterized in that said circuit conductor is interposed between polyethylene naphthalate films. The present invention further provides a printed circuit board, comprising a polyethylene naphthalate film having an elastic modulus of not less than 500 kg/mm2, not more than 1.5x10-5/° C., a hygroscopic expansion coefficient of not more than 1.2x10-5/%RH, a water vapor permeability of not more than 15 g/m2/mil day, a percent water absorption of not more than 2% and a melting point of not higher than 280° C. and a conductor circuit integrated into a laminate with an adhesive layer provided interposed therebetween.
|