Efficient 3D printing via photooxidation of ketocoumarin based photopolymerization

Photopolymerization-based three-dimensional (3D) printing can enable customized manufacturing that is difficult to achieve through other traditional means. Nevertheless, it remains challenging to achieve efficient 3D printing due to the compromise between print speed and resolution. Herein, we report an efficient 3D printing approach based on the photooxidation of ketocoumarin that functions as the photosensitizer during photopolymerization, which can simultaneously deliver high print speed (5.1cm h(-1)) and high print resolution (23 mu m) on a common 3D printer. Mechanistically, the initiating radical and deethylated ketocoumarin are both generated upon visible light exposure, with the former giving rise to rapid photopolymerization and high print speed while the latter ensuring high print resolution by confining the light penetration. By comparison, the printed feature is hard to identify when the ketocoumarin encounters photoreduction due to the increased lateral photopolymerization. The proposed approach here provides a viable solution towards efficient additive manufacturing by controlling the photoreaction of photosensitizers during photopolymerization. 3D printing enables customized manufacturing that is difficult to achieve through traditional material processing but 3D printing with high resolution and high speed is challenging to realize. Here, the authors demonstrate that photooxidation of a ketocoumarin photosensitizer can simultaneously deliver high print speed and high print resolution on a common 3D printer.

Automated summary

Photopolymerization-based 3D printing can achieve customized manufacturing, but the compromise between print speed and resolution remains challenging. A new approach using photooxidation of ketocoumarin as photosensitizer demonstrates high print speed and resolution on a common 3D printer.