Effect of the resin viscosity on the writing properties of two-photon polymerization

While the role of resin viscosity has been largely studied for stereolithography, where a very low viscosity material is preferred, an extensive study of its microscale counterpart, two-photon polymerization, is still lacking. In the present work, we tried to fill the gap by correlating directly the properties of the features produced by two-photon polymerization with the viscosity of four acrylate materials, prepared by mixing two monomers with very different viscosity, and a constant quantity of photoinitiator. Linewidth, polymerization and damage thresholds, dynamic range, and fabrication resolution have been object of investigation in our experiments.