Lubricant useful in a fluid dynamic bearing system, comprises a base fluid comprising at least one mono ester of a branched chain carboxylic acid and a linear, straight-chain alcohol as only ester compound

摘要

Lubricant comprises a base fluid comprising at least one mono ester of a branched chain carboxylic acid and a linear, straight-chain alcohol as only ester compound (I). Lubricant comprises a base fluid comprising at least one mono ester of a branched chain carboxylic acid and a linear, straight-chain alcohol as only ester compound of formula (CH 3(CH 2) n+2CH(CH 3(CH 2) n)-C(=O)O(CH 2) lCH 3) (I). n : = 0; and l : 7-16. Independent claims are also included for: (1) a fluid dynamic bearing system, preferably for rotatable mounting of a spindle motor comprising a first bearing component with at least one first bearing part (12), a second bearing component with at least one second bearing part (20), where the second bearing component is separated from the first bearing component by a bearing gap (22) filled with the lubricant separately and is rotatably mounted relative to the first bearing component; (2) a spindle motor comprising the fluid dynamic bearing system, preferably for driving storage disks of hard disk drives, comprising a base plate (10), in which a first bearing component at least one first bearing part is supported, and a second bearing component, which comprises at least one second bearing part and a hub (14), where the second bearing component is separated from the first bearing component by the bearing gap filled with the lubricant and second bearing component is rotatably mounted by means of the fluid dynamic bearing system relative to the first bearing component and is rotationally driven together with the hub by an electromagnetic drive system around a common rotational axis; and (3) the hard disk drive comprising the spindle motor, which rotationally drives at least one storage disk and a read-write device for writing and reading data to and from the storage disk.