Multimaterial bathless stereolithography using aerosol jet printing and UV laser based polymerization

Conventional stereolithography uses a bath based system, in which a constant layer thickness is applied to realize 3D printing. This approach limits the fabrication of parts consisting of one material only. To overcome this issue, the authors developed a new approach for additive manufacturing using UV curing polymers. In a two step layer-by-layer process, first a liquid monomer film is applied using an Aerosol Jet. Two droplet generators allow the deposition of pure materials as well as various compositions of both materials. In this way, a discrete transition from one pure material to another one from one layer to another is possible. The Aerosol Jet is also able to atomize materials with viscosities greater than 1000 mPa s, allowing a wider range of materials compared to conventional stereolithography. After coating, a laser initiates the one photon polymerization reaction completing one cycle of the layer-by-layer fabrication. In this study, the penetration depth of the raw materials is investigated. In addition, the feasibility of hybrid stereolithography is shown in terms of solid freeform fabrication as well as the multimaterial approach in building direction.