AROMATIC POLYAMIDE FILM

PROBLEM TO BE SOLVED: To provide an arom. polyamide film which gives a composite which does not undergo the degradation in surface properties, such as the occurrence of curl or wrinkles, nor the degradation in functions even when repeatedly used under severe conditions by imparting a specific degree of orientation respectively to each of the outermost surface layers of both sides of the film. SOLUTION: This polyamide film is obtd. from a polyamide contg. 50mol% or higher repeating units represented by formula I and/or formula II wherein Ar1 to Ar3 are each a group represented by formula III [wherein X and Y are each O, CH2 , CO, SO2 , S, C(CH3 )2 , etc.], etc., provided their H atoms may be partly substd. by other substituents; and H atoms in amide bonds may be substd. by other substituents}. The polyamide may be a blend of polymers and may contain necessary additives. The ratio (PA/PB) of degrees of orientation (PA and PB, provided PA>=PB) obtd. from the ATR spectra of the outermost layers of both sides of the film is 1.10 or lower, and the film has a thermal shrinkage at 220 deg.C of 5% or lower, a coefficient of thermal expansion of -1×10 to 40×10 (cm/cm)/ deg.C, and a coefficient of humidity expansion of -15×10 to 20×10 (cm/cm)/%RH.