Dual‐Wavelength Vat Photopolymerization With Dissolvable, Recyclable Support Structures

Abstract Vat photopolymerization (VP) additive manufacturing (AM) is valued for its speed, precision, and material versatility. However, its requirement for support structures limits printable geometries, complicates post‐processing, and generates non‐recyclable waste when typical thermoset resins are used. Here, a wavelength‐selective resin system for VP that enables single‐vat, multi‐material printing with dissolvable supports is introduced. Exposure to visible light produces a rigid, dissolvable thermoplastic, while UV light forms a crosslinked thermoset resistant to dissolution. This process, termed selective solubility vat photopolymerization (SSVP), eliminates the geometric constraints imposed by conventional VP methods, facilitating the creation of complex objects with supports that are removable using green and food‐safe solvents such as D‐limonene and ethyl acetate, as well as mineral oil. Post‐print heat treatment tunes crosslink density and solubility. Dissolved supports can be recycled into fresh resin and reprinted without mechanical property loss, offering a practical, scalable route to reducing waste. Additionally, SSVP provides spatial control of dissolution kinetics, enabling programmable 3D dissolution profiles. By enabling the integration of dissolvable and insoluble regions in a single print, SSVP sets the stage for fully automated and more sustainable AM workflows.