Process for the treatment of mineral building materials

A process for the priming and impregnating treatment of a mineral building material that is exposed to environmental conditions in order to prevent saline deposits and efflorescence of salts comprising applying to a porous surface of said mineral building material by impregnating said surface with:

• (a) a treating material which is an aqueous suspension or solution containing a plurality of silicon-containing ion exchangers, each ion exchanger having the formula:
• ((YO.sub.3)Si(CH.sub.2).sub.x).sub.n EX (I)
• or an oligomer compound thereof, wherein
• x signifies an integer of 1 to 12,
• n signifies an integer of 1 to 3,
• Y is a member selected from the group consisting of H, Na, K, Mg, Ca and Ba,
• E signifies a cation exchanging or anion exchanging group, there being at least one cation exchanging and at least one anion, exchanging group present in said treating material, and
• X signifies H.sup.+ or an alkali cation or alkaline earth cation or an anion, and
• (b) an aqueous or organic emulsion or solution containing a hydrolyzable silane, siloxane or combination thereof,
• said aqueous suspension or solution in (a) being absorbed by said porous surface, reacting said ion exchanger with said mineral building material, condensing said ion exchanger to form a polysiloxane matrix thereon to thereby suppress efflorescence of salts caused by moisture.