3D printed tactile pattern formation on paper with thermal reflow method

Three-dimensional (3D) printing is an effective technique for creating variable tactile patterns, such as braille, on planer cellulose paper for visually impaired persons. In this study, we fabricated printed tactile patterns in a size controllable manner with a fused deposition modeling 3D printer. It was demonstrated that the printed dots were adjusted according to size, thickness, shape as well as interfacial adhesion strength. After the polymeric tactile patterns were formed, the thermal reflow process was conducted on a hot plate as a post-processing step, showing significant improvement in surface smoothness because of the surface tension effect. Furthermore, the interfacial adhesion strength of the printed pattern on cellulose paper was enhanced by tightly bonding on the paper through uniformly reflowing filament melted into cellulose networks after thermal reflow. Compared with punched patterns formed on paper, the printed dots maintained their original shape without any damage caused to the pattern surfaces before or after the tribology test. Therefore, 3D printed tactile pattern with several advantages might be useful in helping visually impaired persons to enhance their sense of touch or to practice tactile recognition.