By employing a unique manufacturing process, unique manufacturing equipment, or a unique combination of materials, a fully integrated, multilayer foamed thermoplastic or elastomeric member or profile having a core member peripherally surrounded by an outer protective layer is attained which is virtually...http://www.google.es/patents/US5904970?utm_source=gb-gplus-sharePatente US5904970 - Integrally bonded, multilayer foamed product
