Polyimide film and manufacturing method thereof, flexible printed circuit board, base material for flexible display, front panel for flexible display, LED lighting device, and organic electroluminescent display device

摘要

The present invention addresses the problem of providing: a polyimide film and a method for manufacturing the same, the polyimide film being suitable in a flexible printed wiring board or the like for an LED illumination device and having enhanced optical transparency, coloration resistance, and low-temperature bending resistance; a flexible printed wiring board which uses the polyimide film; a substrate for a flexible display; a front plate for a flexible display; an LED illumination device; and an organic electroluminescence display device. This polyimide film has a polyamic acid or polyimide formed by an acid anhydride or a derivative thereof, and a diamine or a derivative thereof, either one of which has a fluorene skeleton, the polyimide film being characterized in that the extension rate S of the film two minutes immediately after the film is humidified for 12 hours at 23°C and 55% RH and then immersed in pure water at 23°C is in a range of 0.01-0.10%/minute.