摘要 |
The invention is directed to a process for producing polyimide film, including stretching, at 150° C. to 380° C. and a stretch ratio of 1.2 to 4.0, an unstretched polyimide film which is formed from a polyimide having a repeating unit represented by formula (1): (wherein R represents a tetravalent group derived from cyclohexane; and Phi represents a divalent aliphatic, alicyclic, or aromatic group, or a combination thereof that has a total number of carbon atoms of 2 to 39 and may have at least one connecting group selected from the group consisting of -O-, -SO2-, -CO-, -CH2-, -C(CH3)2-, -OSi(CH3)2-, -C2H4O-, and -S-) and which has an organic solvent content of 0.5 wt. % or more and less than 30 wt. %. The produced polyimide film exhibits transparency, excellent heat resistance, and reduced dimensional changes.
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