In 1953, at what is now the Evonik factory in Witten, Prof. Ewald Katzschmann developed a new process technique for large-scale DMT production, an important intermediate product of polyester. DMT stands for the chemical name di-methyl-terephtalate. The new technique, known as the Witten-Katzschmann process, paved the way for polyester's success worldwide.

The process guarantees the special purity of DMT, enabling it to be re-processed easily and in large quantities. The Katzschmann process is still in use today and has been patented many times over.

High-grade synthetic fibers are produced using the intermediate product DMT. DMT is a vital component of many everyday products as well as in trade and industry. It enables the production of high-quality textiles, sheeting and packaging, e.g. PET bottles. DMT is also required to manufacture technical synthetics, for example in high-pressure hoses.

Starting 2001 till 2006 DMT was produced by Marl-based Oxxynova GmbH & Co. KG with sites in Lülsdorf and Steyerberg. In 2006 Oxxynova was sold to Arques Industries AG.