abstract |
The present invention relates to a three component composition consisting of a polyol component (A) comprising at least two polyols, one with high and one with low molecular weight, and water, a polyisocyanate component (B) comprising a methylene diphenyl diisocyanate (MDI) product with an average NCO functionality of at least 2.5, or a methylene diphenyl diisocyanate (MDI) product with an average NCO functionality of at least 2 and at least one further polyol with an amount of between 1 % and 30% based on the weight of said polyisocyanate component (B), wherein said MDI product and said polyol have reacted at least partially, and a powder component (C) comprising at least one hydraulic binder, preferably cement and/or calcined paper sludge, preferably a calcium compound selected from calcium hydroxide and/or calcium oxide, and optionally one or more aggregates. Polyurethane cementitious hybrid flooring or coating systems having glossy/semiglossy surfaces, good workability and outstanding mechanical properties can be achieved. Blister formation can be avoided. |