By Ryan Whitwam Via Geek
3D printing has come a long way in the last few years, but most of the items produced by 3D printers are all plastic. Printing electrical components would allow these machines to be much more useful, and a team at UC Berkeley might have a solution. To test this circuit printing system, the team created a smart cap that can detect food spoilage with the aid of 3D printed embedded sensors.
Polymers are the preferred material for 3D printing for many reasons, including their flexibility and low cost. They don’t work well for electronic circuits, though. To get around this limitation, the Berkeley researchers printed their circuit design in a combination of plastic and wax (wax standing in for the conductive parts). When the wax was removed, it left hollow tubes which could then be filled with conductive metal, and there you have your circuit.