Method of preventing deterioration of inorganic substrate surface

Abstract

The surface of an inorganic substrate comprising cement, concrete, gypsum or mixtures thereof is treated with a silicate solution or a silica sol comprising a monovalent alkali metal containing component, an ammonium containing component and a silica containing component at a molar ratio of 1:1.about. 10:4.about.5000 corresponding to M.sub.2 O:[R.sub.1 R.sub.2 R.sub.3 R.sub.4 N].sub.2 O: SiO.sub.2 wherein M is Li, K or Na; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each represent a hydrocarbon group or an alkanol group. The underlying inorganic substrate thus has a modified surface layer thereon having a thickness of less than 50 mm, which functions to protect and prevent deterioration of the underlying surface of said inorganic substrate.

Dependencies are inferred from the claim text.