The present invention is directed to a process for applying a chemically resistant coating to a substrate which entails coating a substrate with a composition containing(a) a liquid polyisocyanate component which is present in an amount sufficient to provide an isocyanate index for said composition of at least 30,(b) a polyol component containing at least one organic polyhydroxyl compound having an alcoholic hydroxyl group content of about 0.5 to 15% by weight,(c) water in a quantity of from 20 to 60% by weight, based on the weight of component (b),(d) glycerine in a quantity of about 40 to 200% by weight, based on the weight of component (b), and(e) at least one alkaline earth metal hydroxide or oxide in a quantity of about 50 to 1000% by weight, based on the weight of the glycerine.