Figure 22 (a) 3D model of keyring and (b) 3D printed keyring (64.0 mm × 30.0 mm × 3.6 mm) using 15-DAAQ/TEAOH/R-Br (0.5%/2%/2%, wt %) as PISs.[35]
In addition to this, Xiao et al.[90] also investigated the application of indigo carmine (IDGCM) as a photosensitizer with for 3D printing of photopolymerization. IDGCM possesses excellent good water solubility, visible light sensitivity and biocompatibility, hence it can give the corresponding properties of photopolymerization and 3D printing. The chemical structures of IDGCM, additive, and monomer/oligomers used in corresponding experiments are shown in Figure 23. The indigo carmine-based photoinitiating system induced a rapid photochemical reaction and photobleaching under blue and green LEDs with low light intensity. The photopolymerization system composed of IDGCM/Iod (0.5 %/2 %, wt) and PEGDA 700/deionized water (80 %/20 %, wt) in the presence of 25 mM NaOH can achieve rapid and high-fidelity 3D printing, as shown in Figure 24.
Figure 23 Chemical structures of IDGCM, additive, and monomer/oligomers.[90]