Patent ID: 7939477

Claim:
A lubricant composition for oil-impregnated sintered bearings, which comprises at least one base oil selected from (A) a perfluoropolyether oil represented by the following general formula: RfO(CF 2 CF 2 O) m (CF 2 O) n Rf (where Rf is a perfluoro lower alkyl group having 1-5 carbon atoms, m+n=3-200, and m:n=10-90:90-10, the CF 2 CF 2 O group and the CF 2 O group being bonded at random in the main chain), (B) a perfluoropolyether oil represented by the following general formula: RfO[CF(CF 3 )CF 2 O] p (CF 2 CF 2 O) q (CF 2 O) r Rf (where Rf is a perfluoro lower alkyl group having 1-5 carbon atoms, p+q+r=3-200, q and r each may be 0, and (q+r)/p=0-2, the CF(CF 3 )CF 2 O group, the CF 2 CF 2 O group and the CF 2 O group being bonded at random in the main chain), and (C) a perfluoropolyether oil represented by the following general formula: F(CF 2 CF 2 CF 2 O) s C 2 F 5 (where s=2-100), and an amide-based compound having a perfluoropolyether group represented by the following general formula: RCONHR 1 NR 3 R 4 [IV] (where R is 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 )—, Rf is a perfluoro lower alkyl group having 1-5 carbon atoms, a and b each are an integer of 1-30, R 1 is an alkylene group having 1-30 carbon atoms, some or all of the hydrogen atoms of the alkylene group being replaceable with halogen atoms, and R 3 and R 4 each are a hydrogen atom or an alkyl group having 1-3 carbon atoms).