Effect of Selective Laser Sintering 3D Printing Variables on the Breaking Force of Printed Tablets

In this study, a selective laser sintering 3D printer has been designed and built. 3D laser printing is one of the flexible additive manufacturing methods, which can use different powdered materials. Recently, additive manufacturing technologies have been introduced into the pharmacy, and in August 2015, they received FDA approval as the three-dimensional drug products. By using additive manufacturing in the pharmacy, controlled release, dosage tailored to the characteristics of individuals, the desired morphology of the drugs can be achieved and we move toward the personalization of the medicine. One of the important issues is to determine the properties of tablets before printing. In this paper, the effect of important variables of selective laser sintering on tablet breaking force is investigated with the aid of central composite design and modeling. Using the proposed modeling, the value of each variable can be determined so that the tablets are printed with the required breaking force. The cylindrical tablets with a diameter of 1.2 cm and a height of 3.6 mm were printed for use in the experiments. To fabricate tablets, the thermoplastic polymer, Kollicoat IR (75% polyvinyl alcohol and 25% polyethylene glycol copolymer), was used and 5% paracetamol (acetaminophen) was added. Also, some edible black color was added to increase the absorption of laser light. Laser feed rate, the percentage of the tablet infill density and percentage of the added color are the studied variables. According to the results obtained in the considered range, by increasing laser feed rate, tablet breaking force decreases, but tablet braking force increases by increasing infill density and amount of added color.