Verfahren und Beschichtungszusammensetzung zur Herstellung einer Antireflexionsbeschichtung

A process for the production of a porous anti-reflection coating comprises applying a colloidal-disperse solution (CS) to a substrate, drying the coating and removing organic components by heating. Solution CS is obtained by hydrolytic condensation of silicon compound(s) of formula RaSiX4-a (I) and/or precondensates derived from (I), in which R = 1-10C organic residue, optionally with in-chain oxygen and/or sulphur and/or amino groups; X = H, halogen, hydroxy, alkoxy, acyloxy alkylcarbonyl, alkoxycarbonyl or N(R1)2 (with R1 = H, alkyl or aryl); a = 0, 1 or 2. Hydrolysis/condensation is carried out by the action of water or moisture, optionally in presence of solvent and/or catalyst, and solution CS also contains organic polymer(s) with OH and/or NH groups and an average mol. wt. of 200-500,000 (II), in a mol. ratio of 0.1-100 mmols (II)/mol silane. Also claimed are: (i) an anti-reflection made by this process, and (ii) a coating solution (CS) as above. USE - For coating cathode ray tub es, liquid crystal displays, instrument panels, spectacle lenses, projection screens, solar collectors, car windscreens etc. ADVANTAGE - Enables the production of a low-cost anti-reflective coating with increased light transmission, using only one coat which can be applied over a large area with little variation in film thickness. Applicable to various types of substrate, e.g. glass, metals or plastics, and effective with radiation of different wavelengths