Patent ID: 7387830

Claim:
A coating agent for cellulose-bearing substrate surfaces comprising a liquid phase and binding agent, characterised in that the coating agent includes platelet-shaped pigments and a bonding agent, wherein the platelet-shaped pigments are corrosion-resistant and impermeable to UV light and wherein the bonding agent is capable of producing a bond between platelet-shaped pigments, binding agent and the cellulose-bearing substrate surface, characterised in that the bonding agent is a metal complex with one or more organic ligands, wherein the metal complex contains one or more metal cations which are selected from the group consisting of B, Al, Si, Ge, Sn, Pb, Ti, Zr, V, Cr, Mo, Mn, Fe, Zn and mixtures thereof and the metal complex has at least two functional groups or ligands which with hydroxyl groups form a complex or produce a covalent bond or are displaced out of the complex by hydroxyl groups with the formation of an oxygen-central cation bond.