Novel High-Speed 3D Printing Method Using Selective Oil Sintering with Thermoplastic Polyurethane Powder Printing

Present methods used in three-dimensional (3D) printing, such as selective laser sintering (SLS) and multijet fusion (MJF), have limited applications, especially in relation to the manufacturing of biomedical products. The speed of SLS printing is too low, and high-speed 3D printing technology with MJF uses carbon black particles as a fusing agent, which cannot be removed from the completed 3D printed products. Carbon black and high-energy lasers are not suitable for biomedical applications, especially human implants. A new high-speed 3D method is therefore required. In this study, we used hot oil droplets (175°C) as a new type of fusing agent to melt the biomaterial thermoplastic polyurethane (TPU) powder particles to define the print area. This method replaces lasers and the carbon black fusing agent in high-speed 3D printing technology and is more energy efficient. In addition, this method can be used to not only print on TPU, but also on other flexible materials.