abstract |
A bisulphite addition product of a polyisocyanate and/or polyisothiocyanate prepolymer, said addition product having on an average at least two isocyanate-bisulphite or isothiocyanatebisulphite adduct groups per molecule, having no free isocyanate or isothiocyanate groups, and being freely water-soluble; said prepolymer being derived from a polyisocyanate and/or polyisothiocyanate and a polyhydroxy compound. |