Abstract: The instant invention is directed to a process for the production of weather-resistant rigid molded foams based on polyurethanes having a dimensional stability under heat according to DIN 53 432 of at least 70.degree. C. and a compact surface, a cellular core and an integral density distribution throughout the cross-section of the moldings, comprising foaming a foamable reaction mixture of polyisocyanates, polyhydroxyl compounds, blowing agents and, optionally, other isocyanate-reactive compounds, activators and other auxiliaries in a closed mold under the conditions of in-mold foaming, the improvement wherein the polyisocyanates used are reaction products containing isocyanate groups and urethane groups, said reaction products formed by reacting diisocyanates containing at least one cycloaliphatically bound isocyanate group and no more than one aliphatically bound isocyanate group with sub-stoichiometric quantities of organic polyhydroxyl compounds.

Abstract: This invention relates to the production of composites of organic polyisocyanate plastics and metals. The metals are pretreated with certain adhesion promoters in order to increase adhesion between the metal and the plastic. The pretreated metal sheet or foil is brought into contact with the reaction mixture during the chemical reaction while the plastic is being formed.

Abstract: An aqueous solution of bisulphite blocked polyisocyanate prepolymers is imparted improved storage stability at temperatures up to about 45.degree. C by incorporation of about 0.5 to 20% by weight (based on the weight of bisulphite blocked prepolymer) of an aromatic or alkyl aromatic sulphonic acid of the formula:R(SO.sub.3 H).sub.nwherein R is an aromatic or alkyl aromatic hydrocarbon group having 6 to 15 carbon atoms and n is an integer from 1 to 3. The solution may also contain up to 80 volume percent (based on the total quantity of solvent) of an organic solvent miscible with water and having a boiling point below about 150.degree.C. This solution may be used to finish paper, leather or textiles and to shrink proof keratin containing textiles.