ALEXANDRIA, Va., July 21 -- United States Patent no. 12,686,175, issued on July 21, was assigned to STRATASYS INC. (Minnetonka, Minn.).

"Method of printing a multi-material 3D part and purge tower" was invented by Aaron Daniel Gregg (Bloomington, Minn.), Keith Wade Kooiman (Chaska, Minn.), Karl Anthony Nelson (Minneapolis), Paul Joseph Leavitt (Minneapolis), Thomas James Studanski (Plymouth, Minn.) and Subramaniam Jayanti (Eden Prairie, Minn.).

According to the abstract* released by the U.S. Patent & Trademark Office: "A method of printing a multi-material part in a layer-wise manner with an extrusion-based 3D printer includes providing a sliced digital model of a multi-material part and determining a number of materials in each of the sl...