Lyddæmpende isoleringsmaterialer med høj brandmodstandsvarighed

Insulating material comprises at least an insulating layer and an intumescent layer, where: the insulating layer contains a synthetic foam material, the intumescent layer contains a polyurethane-foam on basis of phosphorus containing polyol; and the thickness of the intumescent layer is 2-98%. An independent claim is included for the process for the preparation of the insulating material, comprising producing a molded body, profile or semi-finished products from the synthetic foam material by well known procedures; producing a liquid reaction mixture by mixing the raw materials necessary for the preparation of the polyurethane-foam on basis of phosphorus containing polyol, and applying the liquid reaction mixture on the relevant surfaces of semi-finished products, where it is foamed and hardened.