US Patent 9677186 Bipolar electrochemical printing

A bipolar electrochemistry printer and method are disclosed wherein electrolytic deposition onto a conductive substrate is accomplished by inducing ionic current in an electrolytic cell disposed above the substrate to undergo charge transfer at the conductive substrate, such that a portion of the substrate becomes a bipolar electrode. The ohmic current in the substrate undergoes a second charge transfer back to ionic current and returning to the cathode of the electrolytic cell. In an alternative embodiment the printing is similarly accomplished by electrolytic etching.