Patent ID: 7323435
Filing Date: 2008-01-29
Classification: C08G

Abstract:
1. A method to form films having hydro and oil repellant properties on surfaces of objects, said method comprising applying to said surfaces aqueous dispersions of fluorinated oligourethanes having a number average molecular weight lower than or equal to 9,000, determined by vapor pressure osmometry, said oligourethanes having a branched structure, optionally crosslinked, formed of the following monomers and macromers: a) aliphatic, cycloaliphatic or aromatic polyisocyanates, having NCO functionality, determined by titration with dibutylamine-HCl (ASTM D2572), higher than 2; b) bifunctional hydrogenated monomers wherein the two functions are chemically different, having formula:  wherein: and one or more of the following compounds: c) bifunctional hydroxyl (per)fluoropolyethers having a number average molecular weight in the range 400-3,000; e) monofunctional hydroxyl (per)fluoropolyethers (e and optionally the following compounds: d) hydrogenated monomers capable to insert a crosslinkable chemical function in the oligourethane, having the formula (Ib), wherein R  wherein d