| abstract |
Use of a perfluoropolyether oil composition as a means for protecting a metal surface from corrosive gases, wherein the perfluoropolyether oil composition comprises a perfluoropolyether base oil and 0.01-50% by weight of a di- or monoamide-based fluorine-containing compound based on the total weight of the base oil and the amide-based compound, and wherein the amide-based compound is a compound of any of the following general formulas [I], [II] or [III]: RCONHR 1 NHCOR [I] wherein R: RfO [CF (CF 3 ) CF 2 O] a CF (CF 3 ) -, RfO (CF 2 CF 2 CF 2 O) a CF 2 CF 2 -, RfO [(CF 2 CF 2 O) a (CF 2 O) b ] CF 2 - or RfO [(CF 2 CF 2 O) a (CF 2 O) b ] CF (CF 3 ) - where Rf is a perfluoro lower alkyl group having 1 to 5 carbon atoms and a and b each integers are from 1 to 30, and R 1 : is an alkylene group having 1 to 30 carbon atoms, wherein a part or all of hydrogen atoms of the alkylene group may be substituted by halogen atoms; R 2 NHCOR [11] wherein R: RfO [CF (CF 3 ) CF 2 O] a CF (CF 3 ) -, RfO (CF 2 CF 2 CF 2 O) a CF 2 CF 2 -, RfO [(CF 2 CF 2 O) a (CF 2 O) b ] CF 2 - or RfO [(CF 2 CF 2 O) a (CF 2 O) b ] CF (CF 3 ) -, where Rf is a perfluoro-lower alkyl group ... |