POLYIMIDE FILM

摘要

Disclosed is a polyimide film which has excellent dimensional stability, heat resistance and other properties of a polyimide, and can exhibit excellent tear resistance even when the film has a small thickness. The polyimide film comprises a polyimide which contains a constituent unit represented by the general formula (1) in an amount of 60 mol% or more, has a Z value calculated in accordance with the following formula: Z = Y/X<SUP>1.5</SUP> [wherein Y represents a value of tear propagation resistance (mN); and X represents a thickness (µm) of the polyimide film] of 0.7 or more, has a thickness of 5 to 40 µm, and has a thermal expansion coefficient of 30 ppm/K or less. In the general formula (1), Ar<SUB>1</SUB> represents a tetravalent organic group having one or more aromatic rings; and R represents a lower alkyl group having 1 to 6 carbon atoms, a lower alkoxy group, a phenyl group, a phenoxy group or a halogen.