COLOR3D – Multicolored 3D printing of wood composites by submicron structuring

• Published in: Additive manufacturing Vol. 75; p. 103723
• Main Authors: Böcherer, D., Li, Y., Kluck, S., Nekoonam, N., Zhu, P., Rapp, B.E., Kotz-Helmer, F., Helmer, D.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05-08-2023
• Subjects: Diffractive coloration; Multi-color 3D printing; Submicron structuring; Wood composites; Submicron structuring; Diffractive coloration; Multi-color 3D printing; Wood composites
• ISSN: 2214-8604; 2214-7810
• DOI: 10.1016/j.addma.2023.103723

The development and fabrication of sustainable materials has become a key task of today’s material research. Bio-based materials for 3D printing are a useful alternative to standard polymer materials, as they are based on renewable resources and can be used to produce individually designed structures with little waste. However, bio-based materials are often not esthetically appealing favoring the use of conventional materials. Here, we present printable biomaterial wood composites based on acrylated epoxidized soybean oil and isobornyl acrylate with a bio renewable carbon content of up to 69 % with structural coloration on the surface. Combining the techniques of high-resolution digital light processing (DLP) and nanoimprint in a one-step process allows us to print 3D structures of renewable biocomposite materials with a colorful, submicron-structured surface. By integration of a submicron-structured transparent foil at the bottom of the printer vat, each printed layer replicates this submicron-structure leading to individual surface structuring of the printed object. In addition, post-treatment of the surface leads to high water repellence with contact angles up to 138° which can induce more stable material properties and durability even under wet conditions. Thus, this processing method overcomes the challenges of multi-color 3D printing, especially for vat photopolymerization techniques, and paves the way for individual fabrication of 3D structures with customized surface structuring and stability.