You can find this info in the PDF brochure of TeXtreme. It's not a patent of Stiga, but Oxeon AB.
TeXtreme® material is protected by the following patents and patent applications (not exhaustive): 11151537.5, 11151534.2, 10187977.3, 06700659.3; PCT/EP2012/050845, PCT/EP2012/050820, PCT/...