Oxide ceramic-based shaped article, e.g. roof tile, has self-cleaning porous, photocatalytically active oxide ceramic surface coating

摘要

An oxide ceramic-based shaped article (A), having a surface which is self-cleaning on contact with rain or spraying with water, has a porous photocatalytically active oxide ceramic surface coating (I) with a specific surface of 25-200 (preferably 40-150) m2/g. An Independent claim is included for the preparation of (A) by: (a) forming a suspension by mixing photocatalytically active oxide ceramic powder, extender and/or adhesive and a liquid phase; (b) applying a layer of the suspension to the oxide ceramic base material; and (c) hardening the layer to form (I).