POLYIMIDE FILM

摘要

PURPOSE: A polyimide film is provided to ensure low expansion by the heat, excellent adhesive force to metal surface and to contribute to realize minute line width when applied to a TAB or COF base film. CONSTITUTION: A polyimide film comprises a repeating unit represented by chemical formula 1. In chemical formula 1, A is selected from functional groups represented by chemical formulas 1-a, 1-b and 1-c; Y is selected from -O-, -OCH2CH2O-, -CO-, -C(CF3)2-, -SO2-, -C(CH3)2 and -CH2-, B is a functional group of chemical formula 1-d; m is an integer of 10-70. The thermal expansion coefficient of the polyimide film is 10 ppm/°C or less.