A new method using light and photosensitive materials opens up many doors into the production of multi-material lithography systems and prints. The researchers involved with the project have dubbed it SMaLL (Solution Mask Liquid Lithography).
Anyone familiar with 3D printing knows how large a role resin 3D printers play. SMaLL uses a similar system as these other forms with a crucial difference. It applies a multi-material lithography twist while also relying on wavelengths of light.
Craig Hawker and his colleagues in University of California, Santa Barbara applied the use of photochromic resins in this method. SMaLL makes use of a mixture of resins that harden at different wavelengths of light. Knowing this they could toy with different wavelengths allowing for a mix of material properties. The team selectively treated areas in a block of resin, creating complex objects with flexible structures. This mixture allowed for a “ligature” that kept the entire material structurally coherent.
Solution Mask Liquid Lithography
The paper describes the structure of the print as one that has networks of chemically and mechanically distinct domains. These domains exist due to photochromic molecules that control polymerization through coherent bleaching fronts. This means that the different properties within the final product create a nuanced structure that is stronger. It also forms a method of single-print, multimaterial production. The team demonstrated the use of the system with “bioinspired soft joints and mechanically reinforced ‘brick‐and‐mortar’ structures“.
The researchers have come up with some very interesting research. While the method is still fresh and very little information is available about it, it’s impressive nonetheless. The entire method could eventually provide a new boost to the DLP and other light-based systems. It also introduces two concepts to the field: Photochromic resins and wavelength differentiation in a single print. These alone make it worth taking note of.
Featured image courtesy of N. D. Dolinski and associates. Retrieved from Advanced Materials website. The abstract for the study is available here.