Fabrication of Nanogratings on Nanocellulose Films Using a Roll-to-Roll Nanoimprinting Method

Nanocellulosic films prepared using mechanically disintegrated cellulose nanofibrils (CNF) and TEMPO-oxidised nanofibrils (TEMPO-CNF) are patterned using thermal R2RNIL. Although CNF films are brittle and they are not thermoplastic with clear softening points, we have shown earlier that the mechanical patterning of the film is possible. Our earlier works demonstrate the micropatterning of CNF films with an interesting temperature dependency and simultaneously the nanoimprinting process smoothed the film surface roughness. In this work we demonstrate the fabrication of roll-to-roll printed nanograting structures with dimensions down to 90 nm. Temperature, printing speed, pressure are and humidity of the films are varied and effect to the printing quality discussed.