FLUOROCHEMICAL COMPOSITION COMPRISING A URETHANE HAVING A FLUOROCHEMICAL OLIGOMER AND A HYDROPHILIC SEGMENT TO IMPART STAIN RELEASE PROPERTIES TO A SUBSTRATE

摘要

The present invention provides a method for preparing a fluorochemical composition comprising a urethane by reacting: (A) fluorochemical oligomer of the formula (I): M<f>mMn-Q<1>-T<1> wherein M<f>mMn represents a 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 is a value of about 2 to 40; n is a value of about 0 to 20; T<1> is an -OH or -NH2 moiety; Q<1> and T<1> together represent an organic residue obtained by removing a hydrogen atom from a chain transfer agent that is functionalized with T<1>; (B) monofunctional compound capable of reacting with an isocyanate and comprising a poly(oxyalkylene) group; (C) isocyanate blocking agent or a fluorine-free oligomer; and (D) isocyanate-reactive compound other than said fluorochemical oligomer, said isocyanate blocking agent, said fluorine-free oligomer and said monofunctional compound; with (E) diisocyanate or a triisocyanate, wherein 33 % to 67 % of the number of isocyanate groups are reacted with the fluorochemical oligomer according to the formula (I), 33 % to 67 % of the number of isocyanate groups are reacted with said monofunctional compound, 0 to 33 % of the number of isocyanate groups are reacted with an isocyanate blocking agent or a fluorine-free oligomer and 0 to 10 % of the number of isocyanate groups are reacted with said isocyanate-reactive compound. Substrates treated with the fluorochemical composition made according to the method described above have good stain release properties particularly for oily stains and water-based stains such as wine, tea and coffee.