Japanese Boosting Stake In U.S. Plants

Mitsui and Co., one of Japan’s largest trading companies, and Tostem Corp., Japan’s leading maker of aluminum housing materials, say they plan to increase their shares of two U.S. aluminum manufacturing plants next month.

Mitsui and Tostem own the two plants - Intalco near Ferndale, Wash., and Eastalco in Maryland - jointly with Alumax Inc. of the United States and Japanese zipper maker YKK.

Mitsui and Tostem officials said Wednesday that increasing their assets in the plants by up to $150 million, effective at the end of March, will boost their holdings to 23 percent and 9 percent, respectively. They currently hold 11 percent and 7 percent.

The deal will boost Mitsui’s share of production to 55,000 tons and Tostem’s to 9,000 tons.

YKK, which has a 7 percent share, said it will not join in the move to increase assets.

The three Japanese companies have collectively owned 25 percent in the two U.S. plants since the end of 1988.