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 Φ 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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