| 摘要 |
<p>A polyimide resin is provided to realize colorless characteristics, transparency and excellent mechanical properties and thermal stability so as to be used in various applications including an interlayer dielectric, passivation layer, liquid crystal aligning layer, flexible display substrate, or the like. A colorless and transparent polyimide resin comprises 4,4'-(4,4'-isopropylidene diphenoxy)bis(phthalic anhydride)(HBDA) as an aromatic dianhydride, and at least one of a diamine having a flexible group and a fluorine-containing diamine as an aromatic diamine. A liquid crystal aligning layer comprising the polyimide resin has a pretilt angle of 0-2 deg. A polyimide film comprising the polyimide resin has an average transmission of at least 85% in a wavelength range of 380-780 nm and at least 88% in a wavelength range of 551-780 nm as measured by a UV spectrometer based on a film thickness of 50-100 micrometers.</p> |
