Lubricant composition, use thereof and aliphatic ether compound
The present invention provides a lubricant composition having high moisture resistance and having physical properties including low viscosity, low evaporability, low-temperature fluidity, and a high viscosity index. The lubricant composition contains (i) an aliphatic ether compound as a base oil and (ii) an antioxidant made from at least alkylated phenylnaphthylamine and phosphite ester, wherein a sum of individual amounts of the alkylated phenylnaphthylamine and the phosphite ester is a predetermined amount, and the alkylated phenylnaphthylamine and the phosphite ester are used in a predetermined ratio.
1. A lubricant composition comprising:
an aliphatic ether compound that serves as a base oil; and
an antioxidant including at least alkylated phenylnaphthylamine and phosphite ester,
wherein a sum of individual amounts of the alkylated phenylnaphthylamine and the phosphite ester, which are contained in the lubricant composition, is 3% to 8% by weight relative to a total amount of the base oil, and
the alkylated phenylnaphthylamine and the phosphite ester are used in such a ratio that the alkylated phenylnaphthylamine and the phosphite ester account for 85% to 95% by weight and 5% to 15% by weight, respectively, of the sum of the individual amounts of the alkylated phenylnaphthylamine and the phosphite ester.
2. The lubricant composition according to claim 1 , wherein the aliphatic ether compound is an aliphatic ether compound having 8 to 300 carbon atoms in one molecule and having 1 to 150 oxygen atoms in one molecule.
3. The lubricant composition according to claim 1 , wherein the aliphatic ether compound is 2-(2-ethylhexyloxy)ethyl ether compound.
4. The lubricant composition according to claim 1 , wherein the aliphatic ether compound is at least one compound selected from the group consisting of compounds having respective structures represented by the following chemical formulae (1) to (10):
5. The lubricant composition according to claim 1 , wherein the alkylated phenylnaphthylamine is N-phenyl-dodecylnaphthalene-1-amine or N-phenyl-octylnaphthalene-1-amine.
6. The lubricant composition according to claim 1 , wherein the phosphite ester is 1,1,3-tris(2-methyl-4-ditridecylphosphite-5-t-butylphenyl)butane.
7. A bearing oil comprising a lubricant composition recited in claim 1 .
8. A bearing which is lubricated with use of a lubricant composition recited in claim 1 .
9. The bearing according to claim 8 , which is a fluid bearing or an impregnated bearing.
10. A motor comprising a bearing recited in claim 8 .
11. A method for lubricating a bearing, comprising:
lubricating a bearing with use of a lubricant composition recited in claim 1 .
12. A method for producing a grease, the method comprising adding a thickener to the lubricant composition of claim 1 .
13. A grease containing a lubricant composition recited in claim 1 .
14. A freezer oil containing a lubricant composition recited in claim 1 .
15. An aliphatic ether compound having a structure represented by any one of the following chemical formulae (1) to (9):