NEW YORK (AP) -- Chemical maker Rockwood Holdings said Sunday it will sell one of its units to a German company, Rockwood's second such sale in as many months.
Rockwood, based in Princeton, N.J., is shedding its clay-based additives business. Altana Group, a specialty chemical company based in Wesel, Germany, will pay $635 million for the unit.
Rockwood said last month that it was selling another unit, its advanced ceramics business, to a European private equity firm in an effort to pay down debt and refocus the company on core businesses. CEO Seifi Ghasemi said Sunday the sale is "another step forward" in a long-term business plan meant to return the best value to shareholders.
As a unit of Rockwood, clay-based additives is relatively small. It had sales of $191.4 million in 2012, or about 5 percent of Rockwood's annual revenue. The unit has about 340 employees, according to Altana, and Rockwood has about 10,200 employees overall, according to its most recent annual report.
The additives are used to modify viscosity, thickness and flow characteristics, and keep solids in suspension in a variety of products, including industrial and architectural coatings, oil and gas drilling fluids, consumer and household care products, and inks, paper and composites.
The unit's employees are based at production sites in the U.K.; Germany; Gonzales, Texas; and Louisville, Ky.
Altana said the purchase will help it grow in Asia. The sale needs regulatory approval.
It is expected to close in the fourth quarter.
Rockwell shares closed Friday at $66.09, up 34 percent since the start of the year.