| 摘要 |
PROBLEM TO BE SOLVED: To provide a grease composition suitable to a roller bearing under a low temperature, and exhibiting stable lubricity for a long period, and provide a bearing filled with the grease composition. SOLUTION: This grease composition comprises a base oil and a thickener, where the base oil contains an ester oil comprising pentaerythritol and a fatty acid and expressed by formula (1): C(CH<SB>2</SB>OCOR<SP>1</SP>)<SB>4</SB>being a pentaerythritol tetraester, wherein R<SP>1</SP>represents 6-12C linear and/or branched fatty acid residue. The composition of the fatty acid at least comprises 51-55 mass% 2-ethylhexanoic acid and 39-49 mass% sum total of caprylic acid and capric acid, provided that caprylic acid is 30 mass% or more and capric acid is 5-10 mass%. COPYRIGHT: (C)2007,JPO&INPIT |
