Evaluation of Dispersion State of CNTs in Resin, and its Curing Characteristics Depending on the Dispersion State

Abstract

DLP (Digital Light Processing) 3D printing has the advantage of fast printing speed, and easy material development due to using liquid resin for printing. In addition, carbon nanotubes (CNTs) are smart material with excellent physical properties, and many application studies as an additive are being conducted. As a study combining CNTs and DLP, it is important to understand the DLP printing process when using photocurable resin including CNT materials. As a basic research on this printing process, we need to understand the curing characteristics of resins including CNTs. Meanwhile, CNTs have a strong tendency to agglomerate by van der Waals forces, and therefore dispersion is essential. CNTs dispersion affects the printing material, especially the curing characteristics of the resin. Therefore, the dispersion state of CNTs inside the resin was evaluated using the UV-Vis spectrophotometer, and the curing characteristics according to the dispersion degree were studied. It was found that the better the dispersion, the wider the light transmission blocking area, which prevented curing and decreased the curing thickness.