Multimaterial printing is becoming somewhat of an arms race as of late. While companies are scrambling to find a method that works, researchers appear to be honing in on one. The method is a state of the art system that using light and photosensitive materials. The researchers have dubbed it SMaLL (Solution Mask Liquid Lithography). The method opens up many doors into the production of Multimaterial Lithography systems and prints.
Anyone familiar with 3D printing knows how large a role photosensitive resins play. While they’ve been around for a while, finding prominent use in DLP and SLA, they definitely achieve a new plateau of interesting applications here. SMaLL uses a similar system as these other forms with a crucial difference. It applies a multimaterial 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.