DSM Dyneema, a subsidiary of Dutch chemical producer DSM, has defended a challenge in the European Patent Office (EPO) from local rival Teijin Aramid relating to its ultra-strong Dyneema fiber. Arnhem-headquartered Teijin Aramid, which makes high-strength fibers Twaron, Technora and Sulfron, challenged the EPO’s grant of a patent to DSM Dyneema that covered pressed products based on specific improved unidirectional (UD) systems. These systems are typically designed and used in high-end armor applications such as helmets, inserts and vehicle protection.

At an oral hearing in The Hague on Sept. 15, DSM convinced the EPO that the patent covering one of its key innovations should be maintained. As a result, the EPO dismissed the opposition and DSM’’s patent remains in force. DSM said its technology is aimed at pressed products with improved performance at higher temperatures, while still maintaining good performance at ambient temperature.