Patent ID: 6096240
Filing Date: 2000-08-01
Classification: B01D,C08G

Abstract:
A composition for removing water from a surface, said composition having a specific weight greater than that of the water, and comprising a perfluoropolyether or fluoropolyether having a number average molecular weight between 300 and 1500 and a non ionic additive having structures:T--OC.sub.f (CFY)--L (I)orL--CF.sub.2 OR.sub.f CF.sub.2 --L (II)with hydrogenated moiety L.dbd.X--CH.sub.2 CH.sub.2 (OCH.sub.2 CH.sub.2).sub.n B wherein X is selected from the group consisting of CH.sub.2 O; CH.sub.2 NR""; CONR""; CH.sub.2 OCH.sub.2 CH.sub.2 NR""; and CH.sub.2 OCOCH.sub.2 Owherein n is such that it satisfied the parameter K defined below,B is selected from the group consisting of OH; SH; NHR""; OCH.sub.3 ; and OCOCH.sub.3,R"" is selected from the group consisting of H, and a C.sub.1-3 alkyl;wherein Y is selected from the group consisting of CF.sub.3 and F;wherein R.sub.f is a fluoropolyether radical containing a chain of randomly distributed repeating units selected from the group consisting of (CF.sub.2 CF.sub.2 O), (CFYO) wherein Y is defined above, (C.sub.3 F.sub.6 O), (CF.sub.2 (CF.sub.2).sub.z O) wherein z is an integer equal to 2 or 3, CF.sub.2 CF(OR.sub.f')O) and (CF(OR.sub.f')O) wherein R.sub.f' is selected from the group consisting of --CF.sub.3, --C.sub.2 F.sub.5 ; --C.sub.3 F.sub.7 and CR.sub.4 R.sub.5 CF.sub.2 CF.sub.2 O wherein R.sub.4 and R.sub.5 are equal to or different from each other and are selected from the group consisting of H, Cl and perfluoroalkyl, the T is a fluoropolyether selected from the group consisting of --CF.sub.3, --C.sub.2 F.sub.5, --C.sub.3 F.sub.7, ClCF.sub.2 CF(CF.sub.3)--, CF.sub.3 CFClCF.sub.2 --, ClCF.sub.2 CF.sub.2 -- and ClCF.sub.2 --, the number average molecular weight of the T--OR.sub.f CFY or CF.sub.2 OR.sub.f CF.sub.2 is between 500 and 1200 and the ratio K by weight between T--OR.sub.f CFY or CF.sub.2 OR.sub.f CF.sub.2 and hydrogenated moiety of said additive is comprised between 1.5 and 3.5.