For example, the fluorochemical compound can be represented by the formula: Rf???Rk???X???H wherein Rf is a monovalent aliphatic group containing at least two carbon atoms, each of which is attached to at least two fluorine atoms; R is a divalent organic radical; k is 0 or 1; and X is ???O???, ???S???, or ???N(R3) in which R3 is H, alkyl containing I to 6 carbon atoms, or a Rf???Rk??? group.