Fiber, fabric, film, molded or blown article comprising a water- and oil-repellent composition comprising a melt blend of components (a) and (b) in which: (a) comprises a repellency-imparting, fluorochemical composition comprising at least one fluorine-containing aromatic ester oligomer comprising (1) at least two repeat units derived or derivable from the reaction of at least one dicarboxylic acid (or a derivative thereof) and at least one polyol, with the proviso that either the dicarboxylic acid (or derivative) or the polyol (or both) is aromatic or heteroaromatic, and (2) fluorochemical endgroups derived or derivable from the reaction of (i) the dicarboxylic acid (or derivative) and at least one fluorine-containing monoalcohol, or (ii) the polyol and at least one fluorine-containing monocarboxylic acid; and (b) comprises a treatable substrate material; with the proviso that, when the treatable substrate material comprises a mixture of at least two polymers, the mixture is non-stratifying.