Fluorochemical composition comprising a polyurethane having a fluorochemical oligomer and a hydrophilic segment to impart stain release properties to a substrate

摘要

A method for preparing a fluorochemical composition comprising a polyurethane by reacting: (A) fluorochemical oligomer of formula (I): M. sup.f.sub.m M.sub.n --Q.sup.1 --T.sup.1, wherein: M.sup.f.sub.m M.sub.n represents fluorochemical oligomer comprising m units derived from fluorinated monomer and n units derived from fluorine-free monomer and wherein the fluorinated monomers and fluorine-free monomers may be the same or different; m represents a value of 2 to 40; n represents a value of 0 to 20; T.sup.1 is --OH or --NH.sub.2 ; Q.sup.1 and T.sup.1 together represent the organic residue obtained by removing a hydrogen atom from a chain transfer agent that is functionalized with T.sup.1 ; (B) difunctional compound capable of reacting with an isocyanate; (C) monofunctional compound capable of reacting with an isocyanate and comprising a poly(oxyalkylene) group with (D) triisocyanate. Substrates treated with fluorochemical compositions prepared according to the method, have good stain release properties, particularly for oily stains and water based stains such as wine, tea and coffee.