17 Synthetic resins, semi-processed; polyurethane foam for insulating purposes; polyurethane film, other than for wrapping; polyurethane sealants; polyurethane film for use in sealing and insulating; semi-worked plastic substances; gum, raw or semi-worked; rubber for use in manufacture; rubber sheets for sealing; articles made of rubber for insulation purposes; articles made of rubber for jointing purposes; articles made of synthetic rubber for insulation purposes; articles made of synthetic rubber for jointing purposes; rings (water-tight -); seals, sealants and fillers.