Water-soluble TPO based nanoparticle photoinitiator

The water-dispersible photoinitiator nanoparticle contains 10% (w/w) of the type I photoinitiator diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO). TPO is highly efficient but water-insoluble. This water-soluble TPO based photoinitiator enables rapid 3D printing of structures prepared in aqueous solutions while bringing environmental advantages by using low-energy curing systems and avoiding the need for solvents.

The extinction coefficient of the new water-dispersible nanoparticles of TPO is more than 300 times larger than the best and most used commercially available water-soluble photoinitiator, Irgacure 2959. The TPO nanoparticles absorb significantly in the range from 385 to 420 nm, making them suitable for use in commercially available, low-cost, light-emitting diode-based 3D printers and UV-curing devices.