Livermore, CA – June 29, 2025 – Researchers at Lawrence Livermore National Laboratory (LLNL) have unveiled a groundbreaking dual-wavelength 3D printing technique that uses light to build complex structures while enabling the clean dissolution of support materials. This innovation promises to revolutionize multi-material additive manufacturing, addressing long-standing challenges in efficiency, waste, and part accuracy.
For years, the Achilles’ heel of 3D printing, particularly Digital Light Processing (DLP) technologies, has been the reliance on cumbersome support structures. These temporary scaffolds, essential for preventing collapse during printing, often lead to time-consuming manual removal, material waste, and potential damage to intricate parts. This has been a significant hurdle for the widespread adoption of DLP in production environments.
The “One-Pot” Solution: Light-Driven Chemical Selectivity
Published in ACS Central Science, the LLNL team, in collaboration with University of California, Santa Barbara (UCSB) researchers, outlines a novel “one-pot” printing approach. This method leverages two distinct light wavelengths to simultaneously create both permanent structures and temporary supports from a single resin formulation.
At the heart of this breakthrough is a custom-built, dual-wavelength negative imaging (DWNI) DLP printer, patented by LLNL engineer Bryan Moran. This ingenious system employs a single digital micromirror device to project both ultraviolet (UV) and visible light concurrently. The UV light triggers the solidification of the final epoxy structure, while the visible light cures a specially designed degradable thermoset material that dissolves post-printing.
“This work adds another option to the growing range of multi-material printing possibilities,” said principal investigator Maxim Shusteff. “Using multiple materials is critical to many manufacturing processes, and that’s been hard to accomplish using 3D printing. Dissolving a sacrificial material is much more automation-compatible and less cumbersome than manual removal.”
Clean Dissolution and Unprecedented Geometries
After a thermal post-processing step, the printed objects are immersed in a basic water-based solution. The magic happens here: the visible-light-cured supports gently dissolve away, leaving the primary structure perfectly intact, without any damage or residue.
The team successfully demonstrated the fabrication of intricate, free-floating designs, including interlocked rings and a “ball-in-a-cage” — geometries that are incredibly difficult, if not impossible, to produce with conventional layer-by-layer methods and their accompanying support removal challenges.
“Our one-pot embedded printing approach improves the fidelity of unsupported, free-floating structures, such as overhangs and cantilevers, by using degradable supports that act as temporary scaffolds to prevent collapse and misalignment during fabrication,” explained first author Isabel Arias Ponce, a UC National Laboratory Fees Graduate Scholar and soon-to-be LLNL materials engineer. She added that this approach could also enable the in-situ fabrication of mobile components, eliminating manual assembly and boosting production efficiency.
A Broader Look: Advancing Beyond Traditional Support Solutions
While LLNL’s breakthrough harnesses light and chemistry in a single resin, other innovations in the 3D printing landscape also aim to tackle the support material challenge. For instance, companies like Bambu Lab have introduced dual-nozzle Fused Deposition Modeling (FDM) printers, such as their H2D model.
Bambu Lab’s approach uses two physical print heads: one for the main model material and a second dedicated to a specialized support material, often a water-soluble PVA (Polyvinyl Alcohol). After printing, the model is simply submerged in water, and the PVA support dissolves, leaving a clean part. This FDM-based method offers a different path to automated, residue-free support removal, particularly for larger-scale plastic parts.
While Bambu Lab’s dual-nozzle FDM printers excel in multi-material applications for desktop manufacturing, LLNL’s dual-wavelength DLP technique focuses on the high-resolution, intricate world of light-cured resins. Both innovations underscore a critical trend in additive manufacturing: moving beyond labor-intensive manual support removal towards more automated, precise, and material-efficient solutions.
The LLNL work, funded through the Laboratory Directed Research and Development program and the Lawrence Postdoctoral Fellowship, represents a significant leap forward. By providing a cleaner, more efficient, and more versatile method for creating complex geometries, it paves the way for wider industrial adoption of advanced 3D printing technologies across diverse sectors, from medical devices to aerospace.