Korrosionsschutzbeschichtungen, insbesondere fuer Aluminium, und Mischungen zu ihrer Herstellung

(A1) Die Erfindung betrifft eine Korrosionsschutzbeschichtung fuer Metalle, insbesondere fuer den Korrosionsschutz von Aluminium, umfassend - ein ggf. ausgehaertetes Bindemittel oder Bindemittelsystem - in dem ggf. ausgehaerteten Bindemittel oder Bindemittelsystem verteilte Partikel eines Korrosionsschutzpigments aus einer Legierung aus Zink und Magnesium mit einem Zinkgehalt von 80 Gew.-% oder weniger, bevorzugt 74 Gew.-% - vorzugsweise keine Chromverbindungen - ggf. weitere partikelfoermige Feststoffe, wobei der volumenbezogene Anteil der Partikel des besagten Korrosionsschutzpigments an der Gesamtheit der in der Korrosionsschutzbeschichtung vorhandenen Feststoffpartikel 70% oder mehr, bevorzugt 80% oder mehr, weiter bevorzugt 90% oder mehr und besonders bevorzugt 95% oder mehr betraegt und das Verhaeltnis der Pigmentvolumenkonzentration in der Korrosionsschutzbeschichtung zur kritischen Pigmentvolumenkonzentration 0,9 bis 1,1 betraegt.

DE 102009052399 A1 UPAB: 20110609 NOVELTY - Corrosion-protecting coating for a metal, preferably aluminum comprises: an optionally cured binder or a binder system; a corrosion-protecting pigment of an alloy of zinc and magnesium distributed into the binder or the binder system; and optionally additional particulate solids, where the coating does not comprise chromium compounds. The proportion of the pigment particles to the total solid particles present in the coating is greater than or equal to 70 vol.%, preferably greater than or equal to 95 vol.%. The pigment concentration in the coating is 90-110 vol.% of a critical pigment concentration. DETAILED DESCRIPTION - Corrosion-protecting coating for a metal, preferably aluminum comprises: (a) an optionally cured binder or a binder system; (b) a corrosion-protecting pigment of an alloy of zinc and magnesium with a zinc content of less than or equal to 80 wt.%, preferably 74 wt.% distributed into the binder or the binder system; and (c) optionally additional particulate solids, where the coating does not comprise chromium compounds. The proportion of the particles of the corrosion-protecting pigment to the total solid particles present in the coating is greater than or equal to 70 vol.%, preferably greater than or equal to 95 vol.%. The pigment concentration in the coating is 90-110 vol.% of a critical pigment concentration. INDEPENDENT CLAIMS are also included for: (1) a mixture for producing the corrosion-protecting coating, comprising the components (a) and (b), optionally at least one solvent and optionally the additional particulate solids, where the proportion of the pigment particles to the total solid particles present in the mixture is greater than or equal to 70 vol.%, preferably greater than or equal to 95 vol.%, and the non-volatile components of the mixture based on the pigment concentration is 90-110 vol.% of the critical pigment concentration; (2) producing the corrosion-protecting coating on a metal surface, preferably aluminum surface, comprising applying the mixture on at least a portion of the metal surface, and optionally curing the binder; and (3) a subject comprising a main body made up of a metal or an area of a metal, and the corrosion-protecting coating arranged on the main body consisting of the metal and the metallic area of the main body, where the corrosion-protecting coating at least partially covers the main body consisting of the metal and the metallic area of the main body. USE - The mixture is useful for producing the corrosion-protecting coating on a metal surface, preferably aluminum surface (claimed). ADVANTAGE - The coating: ensures improved corrosion protection, preferably cathodic corrosion protection for components made up of aluminum or aluminum alloys; and is environment-friendly since it dose not contain chromium compounds.