Security Pacific will sell half of a finance unit.

The nation’s sixth-largest bank holding concern has agreed to sell half of its Japan Security Pacific Finance Co. to Mitsui & Co. for an undisclosed price. As a joint venture, the consumer finance unit will substantially increase the reach of Japan Security Pacific Finance, which has $200 million in assets and has been operating in Japan since 1978 but has only five branches. The venture will give Mitsui, a diversified trading company, entry into consumer finance, a field in which it is not now involved.