This research grade (not for human use) zirconia 3D-printing ink can be used for printing using a direct extrusion (pneumatic or mechanical) 3D-printer into multi-layered, three-dimensional objects at room temperature. This ink should only be used in a well-ventilated environment. The extruded material rapidly solidifies and allows creation of complex, user-designed forms. Despite being mostly zirconia, the printed solid material is flexible (may even have limited elastic properties). The solids loading of the as-dried material is 70 vol.% zirconia, 30 vol.% PLGA. This zirconia ink can be utilized to create three-dimensional structures on their own, or co-3D-printed with other 3D-printing inks to create multi-material structures. The ink may also be mixed with other 3D-printing inks to compound them prior to utilization. Due to the mechanical flexibility of the material after drying, complex 2D and 3D forms can be created. This ink may also be utilized in non-3D-printing applications such as coating (dip-coating or direct painting), thread fabrication, or casting into molds.
Our zirconia 3D-printing ink is comprised of micron sized zirconia particles suspended in a mixture of organic solvents containing dissolved, high molecular weight elastomeric, biocompatible polyester (polylactic-co-glycolic acid; PLGA). Prior to further use, to remove residual solvents after 3D-printing (or other application such as coating, direct painting etc) the zirconia composite material should be washed in 70% ethanol and then by water. The 3D-printed zirconia can be used as flexible ceramic composite or it can also be sintered (1650 °C recommended) in a non-oxidative atmosphere to yield zirconia parts. As sintered, zirconia is highly chemically and thermally stable, and can be used for a wide variety of high temperature applications. Zirconia also has numerous hard biological tissue (teeth and bone) applications, and can serve in it as as-printed, washed form as flexible ceramic composite cell scaffold, or in its sintered form, as a rigid ceramic scaffold/implant.