Researchers develop a 3D printing ink that recycles with water
Waste-derived material is made from 70% lignin and is an ink that’s designed for direct ink writing
Researchers at the Helmholtz-Zentrum Hereon’s Institute of Functional Materials for Sustainability in Teltow, Germany, have created a water-based 3D printing ink composed of approximately 70% lignin, a byproduct of paper-making processes and biomass extraction.
The ink was designed for direct ink writing, a 3D printing technique that builds objects at room temperature by extruding material layer by layer.
The team formulated the ink to flow through printer nozzles under pressure and solidify without chemical treatments or high-temperature curing – a limitation of earlier lignin-based inks. Those materials typically required permanent bonding processes that prevented recycling, while the new formulation avoids these steps and allows printed objects to be dissolved and reformed multiple times by adding water.
“We wanted to demonstrate that waste-derived materials like lignin can meet the technical demands of modern 3D printing while improving sustainability,” said Dr. Maria Balk, one of the lead authors of the study published in ACS Sustainable Chemistry & Engineering. “To do this, we transformed an industrial waste product into a water-based 3D printing ink that can be fully recycled simply by adding water.”
The ink maintained structural performance after multiple recycling cycles through rehydration during tests, and material strength was recovered quickly after printing. It also did not require any additional processing to hold its shape. In contrast, most polymer-based inks derive from fossil fuels and cannot be reprocessed.
“Lignin is one of the most abundant components of wood, yet largely underused,” stated Prof. Francesca Toma, corresponding author of the study. “Turning it into a fully recyclable material shows how waste can drive innovation in an industry that urgently needs sustainable solutions.”
The research team indicated plans to scale production and test applications where low-energy processing and material reuse offer operational advantages.
Potential applications include prototyping and component manufacturing across consumer goods, medical devices, and vehicle systems.
