Greg Babe, who retired last year as head of Bayer’s U.S. operations, has joined conductive inks maker Liquid X Printed Metals as CEO. The firm also raised an undisclosed amount in its first funding round. One of the founders of Pittsburgh-based Liquid X, Richard D. McCullough, also founded Plextronics, a maker of conductive polymers and inks. Liquid X, a Carnegie Mellon University spin-off like Plextronics, has developed inks based on gold, silver, and other metals to economically print wiring for electronics. Investors include Pennsylvania-state-backed Innovation Works and private equity firm Newlin Investment.