Celanese AG, Frankfurt, and Wacker-Chemie GmbH, Munich, have sold their 50 per cent stakes in Vinnolit Kunststoff GmbH, Ismaning, to Advent International Corp. At the same time, Celanese Chemicals Europe GmbH, a Celanese AG subsidiary, has completed the sale of the whole of Vintron GmbH to Advent. The transaction is effective from January 1, 2000.