Patent ID: 6124021
Filing Date: 2000-09-26
Classification: B32B,G11B,Y10S,Y10T

Abstract:
A biaxially oriented laminate film comprising a wholly aromatic polyamide layer A and a wholly aromatic polyamide layer B laminated on one surface of the wholly aromatic polyamide layer A, whereinthe surface not in contact with the wholly aromatic polyamide layer B of the wholly aromatic polyamide layer A has projections having an average height of 2 to 85 nm and an average width of 20 to 500 .mu.m at a density of 4 to 2,500/mm.sup.2 ; the wholly aromatic polyamide layer B contains inert fine particles B; the surface, not in contact with the wholly aromatic polyamide layer A, of the wholly aromatic polyamide layer B is rougher than the surface, not in contact with the wholly aromatic polyamide layer B, of the wholly aromatic polyamide layer A;the wholly aromatic polyamide is a polymer containing at least 70 mol % of a recurring unit represented by the following formula (A):--(HN--Ar.sub.1 --NHCO--Ar.sub.2 --CO)-- (A)wherein Ar.sub.1 is a residual aromatic group obtained by removing two --NH.sub.2 groups from an aromatic diamine and Ar is a residual aromatic group obtained by removing two --COOH groups from an aromatic dicarboxylic acid: andthe biaxially oriented laminate film has a total Young's modulus of at least 2,000 kg/mm.sup.2 in two directions, on the film plane, crossing each other at right angles.