Freedom of design for 3D printing

"MatrixPrint": a new 3D printing platform consisting of a new type of jelly-like support matrices and nano-inks. Photo: Dorothea Helmer

A new technology will make 3D printing of various materials faster and more precise. The Federal Ministry of Education and Research has selected the "MatrixPrint" project for funding in its "NanoMat Futur" competition for young researchers. Dr. Dorothea Helmer from the Department of Microsystems Engineering at the University of Freiburg will thus receive 1.9 million euros to develop so-called pseudoplastic matrices for 3-D printing of glass, metal and polymers.

"Previous methods of 3-D printing require support structures in order to be able to produce complex structures with high precision," explains Helmer. "This costs a lot of time and additional material and drastically limits the freedom of design." In addition, it is difficult for scientists to create thin channel structures, which are necessary, for example, for the production of artificial blood vessels or small synthesis reactors due to the often insufficient precision of 3-D printing. "In addition, many fundamentally different printing methods and machines are required to produce different materials in 3-D printing," says the Freiburg researcher.

In her "MatrixPrint" project, Helmer is therefore developing a 3D printing platform consisting of a new type of jelly-like support matrices and nano-inks. This technology can structure metals, glasses and polymers on a single machine. In addition, it does not require printed support structures, which allows a high freedom of design. The printing is done by a system in which Helmer introduces the nano-inks into the matrix through a fine capillary. These newly developed support matrices can keep the injected ink in shape despite differences in density and volume growth. Once the ink has hardened in the support matrix, the resulting three-dimensional structures can be released from the soft matrix. The liquid phase interface between matrix and ink results in particularly smooth structural surfaces. The supporting matrix can then be reused for further prints. The Freiburg researcher wants to produce fine channel structures with integrated electronics in this way, for example to enable cell experiments or analyses on-chip.

Dorothea Helmer studied chemistry in Karlsruhe and received her doctorate in organic chemistry and biochemistry at the Technical University of Darmstadt. She then carried out research at the Institute of Microstructure Technology at the Karlsruhe Institute of Technology and has been working at the chair of „Process Technology" of Prof. Dr. Bastian E. Rapp group at the Department of Microsystems Engineering at the University of Freiburg since 2018.