High thermal stability of optical transparency in cellulose nanofiber paper

Cellulose nanopapers have been shown to maintain high optical transparency after high temperature heating at 150 degrees C. High temperature heating to around 150 degrees C is inevitable in electronic device processing. If a polyethylene terephthalate film is held at 150 degrees C for tens of minutes, cyclic oligomers migrate to the film surface, causing surface roughness that decreases the film transparency. However, because cellulose nanofibers have high thermal stability, the transparent nanopapers maintained their smooth surfaces and high optical transparency, even after heating to 150 degrees C for tens of minutes. These findings indicate the suitability of cellulose nanofiber papers for continuous roll-to-roll processing. (C) 2013 AIP Publishing LLC.