Process study on roll-to-roll ultraviolet (UV) embossing

We aim to develop roll-to-roll (R2R) large area ultraviolet (UV) embossing process for structuring micro features on flexible plastic films. Critical challenges in R2R UV embossing include but not limited to (i) precise deposition of liquid UV curable resins, and (ii) realizing low temperature and low pressure micro-structuring using UV curing. We have developed a R2R UV embossing system, which consists of an unwinding unit and a rewinding one for handing flexible plastic films, a slot die coating unit, an embossing roller, and a UV lamp for exposure and curing of UV sensitive resins. The system can handle 500 mm web-width flexible films; the coating width of the slot die is 250 mm. By using different flexible moulds, various structures were fabricated via R2R UV embossing.