Schmidt, H.H.SchmidtNass, R.R.NassSporn, D.D.SpornBrehler, K.P.K.P.BrehlerEgger, C.C.Egger2022-03-082022-03-081994https://publica.fraunhofer.de/handle/publica/303063The invention relates to a process for the production of substrates coated with <alpha>-Al<-2 O<-3 by the hydrolytic condensation of aluminium compounds. Hydrolyzable aluminium compounds based on the general formula of AlRR'R'', where R, R' and R'' each mean branched or unbranched alkyl, alkoxyl or acyloxy groups or anions are converted into aluminium/ <beta> diketone compounds before hydrolysis with <beta> diketones of the formula 1 where R->1, R->2 and R->3 mean branched or unbranched alkyl or alkoxyl or hydrogen atoms respectively. The aluminium/ <beta> diketone complex compounds are condensed. The substrates are coated with a colloidal solution of the condensed aluminium/<beta> diketone complex compounds and heated to temperatures of >= 900<degrees Celsius>Cde608666patent1990-4016637