METHOD OF WATERPROOFING POROUS BUILDING MATERIALS AND STRUCTURAL ELEMENTS Russian patent published in 2003 - IPC

FIELD: manufacture of building materials. SUBSTANCE: invention area covers all types of porous building materials, which can come into contact with liquids. In particular, building material is treated with at least one low- viscosity (<100 mPa.s) liquid at 12 C, said liquid is a substance or mixture of substances based on epoxide resins constituted by solvent-free aliphatic multifunctional reactive components and amine-type aliphatic hardeners and/or polyurethane prepolymers containing 2 to 30% isocyanate. Substance is then allowed to penetrate into porous structure of building material within desired effect zone in order to chemically react and virtually completely fill porous structure thereby forming therein waterproofing barriers. More specifically, chemical reaction results in foaming and hardening of porefilling substance, which preserves sufficient ability to swell when in contact with a liquid in order to tightly clog remaining free space of pores. When initial liquid enters, under pressure, moisture-saturated porous structure, it does not essentially mix with moisture but rather displaces it from pores. EFFECT: essentially improved waterproofness of materials. 11 cl, 7 dwg, 1 tbl