摘要 |
The present invention concerns a foldable duct (4) made of glass or stone fibres and binder agent having a foil (1) laminated thereon, on the inside and outside of the duct, wherein the foil (1) at least comprises: -an outer layer of aluminium (5), -an intermediate layer of a thermoplastic polymer (6) having a lower melt point than polyethylene, positioned closest to the outer layer of aluminium (5), -an intermediate layer of polyethylene (7), positioned between the intermediate layer of thermoplastic polymer (6), and -an inner layer of a thermoplastic polymer (8) having a lower melt point than polyethylene. |