LUBRICANT AND SPINDLE MOTOR AND RECORDING DISK DRIVE UNIT USING THE SAME

摘要

PROBLEM TO BE SOLVED: To make a lubricant for a liquid dynamic pressure bearing device have a sufficiently low crystallization starting temperature of a solid phase without being lost by evaporation even by use over a long period of time and usable in a motor etc. having a wide service environmental temperature range. SOLUTION: The lubricant comprises two kinds of ionic liquids in which cations or anions are common and has≤-40°C crystallization starting temperature of the solid phase and≤25 mPa viscosity at room temperature. One of the ionic liquids is in a liquid form having≤30 mPa viscosity at room temperature and the freezing point is≤-40°C freezing point. The other ionic liquid is in the liquid form having≤30 mPa viscosity at room temperature and the freezing point is≥-40°C. COPYRIGHT: (C)2008,JPO&INPIT