Lonza Group Ltd. and Arch Chemicals Inc. have signed an agreement in which Lonza will buy 100 percent of Arch Chemicals’ outstanding shares of common stock.

BASEL, Switzerland/NORWALK, CT – Lonza Group Ltd. and Arch Chemicals Inc. have signed an agreement in which Lonza will buy 100 percent of Arch Chemicals’ outstanding shares of common stock. Upon completion of the transaction, Lonza will have a leading microbial-control business with 2010 pro-forma sales in this life science market of approximately $1.6 billion.