Polyimide film for flexible printed board and flexible printed board using the same

摘要

The present invention provides a flexible printed circuit which is free from curl, torsion and warpage due to temperature change and excellent flexural endurance. By using polyimide film having an average coefficient of thermal expansion of 1.0x10^-5 to 2.5x10^-5 cm/cm/° C. in a temperature range of 100° C. to 200° C. and a stiffness value of 0.4 to 1.2 g/cm as the base film for the flexible printed circuit, a flexible printed circuit having excellent thermal dimensional stability and flexural endurance can be prepared.