The present invention relates to an aqueous dispersion, comprising or consisting of A) at least one cyclic olefin copolymer, B) at least one surfactant; optionally C) at least one adhesion promoter; optionally D) at least one film-forming resin; optionally E) at least one additive; and F) water. Additionally, the invention relates to methods of manufacturing the aqueous dispersion, to an article, which comprises at least one substrate and at least one coating layer obtained from the aqueous dispersion and applied onto the substrate; and to methods of improving MVTR of a substrate.