Patent ID: 7914893

Claim:
A particle comprising a substrate and coated thereon an anion-binding layer which comprises one or more anion-forming organic active compounds, wherein at least one of the one or more anion-forming organic active compounds is not an anionic or anion-forming dye, wherein one or more transparent, semitransparent and/or opaque layers of metal oxides, metal oxide hydrates, metal suboxides, metals, metal fluorides, metal nitrides, metal oxynitrides or a mixture thereof has been applied to the substrate beneath the anion-binding layer, or wherein the substrate is flake-form shaped and is selected from the group consisting of glass flakes, SiO 2 flakes Al 2 O 3 flakes, BiOCI flakes, graphite flakes, synthetic and natural flake-form iron oxide and flake-form metals, and aluminium, titanium, bronze, steel and silver metal flakes, wherein the metal flakes are optionally passivated, or wherein the substrate is flake-form shaped and has a diameter of 5 to 200 μm, an average thickness of 0.05 to 10 μm, and an average aspect ratio of 5 to 750.