Effects of UV Intensity, Line-speed, and Light Distribution on Conversion and Surface Elastic Modulus of Roll-to-roll UV-cured Film

Abstract

Roll-to-roll UV nanoimprint lithography (R2RUVNIL) is a promising technology for fabricating nanostructures on flexible films, but its application requires finding feasible operating conditions to peel-off the UV resin from the mold. Furthermore, to achieve the required nanostructure, conversion of the UV resin needs to be precisely optimized in terms of the UV intensity and line speed. In this study, (1,6-bis(acryloyloxy)hexane) resin was cured by roll-to-roll UV-curing while monitoring its conversion and surface elasticity by Fourier transform infrared spectroscopy and a nano indenter, respectively. It was found that the conversion increases by up to 85% with a decrease in line speed and increase in UV intensity. The effect of varying the distribution of UV light on the roller mold was also investigated, which revealed that a sharp distribution of UV light is effective in increasing the surface elastic modulus from 0.2 to 1.0 GPa at 0.6 conversion.