Ausimont S.p.a.

Roberta Marchetti

Stefano Turri

Daria Lenti

Massimo Malavasi

Use for protective coatings of compositions comprising (% by wt.): A) from 10 to 60% of a A1) (per)fluoropolyethereal prepolymer having a polyisocyanic functionality obtainable by reacting a bifunctional having hydroxylic functionality, said fluoropolyethers having --CH.sub.2 OH terminations directly linked to a perfluoroalkylic group CF.sub.2 or CF.sub.2 CFX (X.dbd.Cl, F) or CF(CF.sub.3), with a polyisocyanate containing isocyanurate rings, preferably obtained by cyclotrimerization of HDI, IPDI or other monomeric diisocyanates, by utilizing an excess of isocyanate groups comprised between 10 and 80% by moles; the above fluoropolyether prepolymer can be partially or totally replaced by A2) non fluorinated polyisocyanates containing isocyanurate rings and/or hydrogenated polyisocyanate prepolymers; B) from 0.1 to 50% of a (per)fluoropolyether having bifunctional hydroxylic functionality of the type --CF.sub.2 CH.sub.2 OH, --CF.sub.2 CFXCH.sub.2 OH (X.dbd.Cl, F) or --CF(CF.sub.3)CH.sub.2 OH; or polyfunctional hydroxylic functionality termination but containing at least 5% by weight, preferably 10%, of the same type of termination indicated above for the bifunctional; or (per)fluoropolyethers prepolymers as defined in A) but having a lower prepolymerization degree so to leave free oxydrilyic functions of the type --CF.sub.2 CH.sub.2 OH, --CF.sub.2 CFXCH.sub.2 OH (X.dbd.Cl, F), or --CF(CF.sub.3)CH.sub.2 OH; or the latter prepolymers having free hydroxilic functions can be used alone as a single component, being component A) 0%; C) 10-90%, with respect to the resin of a diluting solvent.

Coatings based on perfluoropolyethers

A method of protecting objects from graffiti using fluorinated polymers based on fluoropolyethers in a dry formulation wherein the fluorinated polymer includes a fluorinated part R.sub.F and optionally an hydrogenated part R.sub.H not containing groups capable of linking to basic acceptors by means of hydrogen bonds, the bonds linking the fluorinated part, derived from (per)fluoropolyethers, to the hydrogenated part being of simple C--O ether type, the T' terminal groups being such as to render the structure bi- or polyfunctional thus making possible the curing reaction, and subsequent curing of the fluorinated polymer.

Growing community of inventors

Voghera, Italy

Roberta Marchetti