Dual‐Wavelength Vat Photopolymerization With Dissolvable, Recyclable Support Structures

Abstract

Vat photopolymerization (VP) additive manufacturing (AM) is valued for itsspeed, precision, and material versatility. However, its requirement forsupport 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 tovisible light produces a rigid, dissolvable thermoplastic, while UV light formsa crosslinked thermoset resistant to dissolution. This process, termedselective solubility vat photopolymerization (SSVP), eliminates the geometricconstraints imposed by conventional VP methods, facilitating the creation ofcomplex objects with supports that are removable using green and food-safesolvents such as D-limonene and ethyl acetate, as well as mineral oil.Post-print heat treatment tunes crosslink density and solubility. Dissolvedsupports can be recycled into fresh resin and reprinted without mechanicalproperty loss, offering a practical, scalable route to reducing waste.Additionally, SSVP provides spatial control of dissolution kinetics, enablingprogrammable 3D dissolution profiles. By enabling the integration ofdissolvable and insoluble regions in a single print, SSVP sets the stage forfully automated and more sustainable AM workflows.