Metal composite elements and use of PUR foams or PIR obtained polyester polyols obtainable by processes for the preparation of polyester polyols with small amounts of residue of dioxin, for the preparation of compounds of metal elements

Element metal compound comprising a PUR foam or PIR obtained by a process comprising the steps of a) conversion of a polyester polyol obtainable by a process wherein at least one carboxylic acid anhydride (A) are mixed, diethylene glycol (B) i) at least one glycol C2-C4 (C) and at least one dicarboxylic acid C5 - aliphatic C12 (D) or ii) at least one C5 glycol - C10 (E) and at least one dicarboxylic acid C4 ( F), the molar ratio of components (B) to (a) in the range of 1.5 to 1 to 1.1 to 1 and the weight ratio of components (a) and (B) based on the weight all components of the mixture is in the range between 66 and 95% by weight, b) a component containing polyisocyanate, c) a disintegrant, d) one or more catalysts, e) optionally agents case flame retardants and / or other auxiliaries and additives.