Process for the protection of stony or coating surfaces

摘要

(Per)fluoropolyether cured polymers to be used as antigraffiti for the preventive treatment of building materials and coatings surfaces wherein (per)fluoropolyether polymers before curing have hydroxylic polyfunctional terminals of general formula: <CHEM> wherein: Z2 represents the bifunctional group -O-CO-NH-R-NH-CO-O-, R being an alkylene radical from 1 to 20 carbon atoms, Rf represents the R'f-Y' group wherein R'f is a bifunctional radical derived from (per)fluoropolyethers; Y' is a bivalent linking organic radical s is an integer equal to 1 or 2; P represents a trivalent or tetravalent radical derived from polyols.