| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method of stably performing continuous production which hardly causes a trouble such as breakage of a clamping part of a film edge part with respect to a method of producing a polyimide film which is controlled such that the linear expansion coefficient in the transverse direction is smaller than the linear expansion coefficient in the machine direction. <P>SOLUTION: The method of producing polyimide film is characterized by: casting a solvent solution of a polyimide precursor on a support; removing a solvent in the solution; peeling a cast film from which the solvent is removed, as a self-sustaining film; starting the stretching of the self-sustaining film having a solvent content of 25 to 45% and an imidization rate of 5 to 40%, in the transverse direction at an initial heating temperature of 80 to 240°C; and, thereafter, heating the stretched film at a final heating temperature of 350 to 580°C. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
