US Ink, a division of Sun Chemical Corporation, Carlstadt, NJ, announced that John C. Corcoran has been promoted to the position of vice president, sales. Mr. Corcoran, who had been national accounts manager for the division, will continue to report to Ronald C. Baker, president, US Ink.      “This promotion recognizes John’s leadership in unifying Sun Chemical’s news ink customer base,” said Mr. Baker. “Over the years, John has demonstrated a remarkable ability to meet marketplace challenges...