PARSIPPANY, N.J. (April 9)—Degussa Corp. and Engineered Carbons Inc. have launched a joint venture to produce a full range of furnace, thermal and specialty blacks from six U.S. plants previously operated separately by the two companies. In effect, the deal combines the North American carbon black business of Degussa and Ameripol Synpol Corp. subsidiary ECI. Degussa, the North American subsidiary of Degussa A.G., and the venture, Degussa Engineered Carbons L.P., also entered into an exclusive agreement giving Degussa sales responsibility for the products of the new business. Degussa Engineered Carbons is based in Parsippany, where Degussa is headquartered, and began operating April 1. The joint venture serves the rubber and specialty markets.