Degussa Engineered Carbons, LP (DEC) has appointed Mark Leigh vice president and business director, pigment blacks. Mr. Leigh, who is currently DEC regional sales manager in Chicago, replaces Dr. Karin Otto, who has accepted a new position with Degussa AG in Frankfurt.      “We are extremely pleased to have Mark as vice president of our pigment blacks unit,” said Jack L. Clem, president and general manager of DEC. “Mark has a wealth of experience in the industry that will benefit our customer...