Charge control agent for fluid dynamic bearing motor lubricant
US9728220B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 18, 2016 |
| Grant date | Aug 8, 2017 |
| Priority date | — |
| Expiry date | May 18, 2036 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2370/12
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Embodiments disclosed herein generally relate to magnetic recording systems having a spindle motor and, more particularly, to an optimized lubricant for bearings within the spindle motor. A lubricant used in a fluid dynamic bearing motor has an antioxidant additive and a charge control agent dissolved in a diester base oil. The charge control agent is chemically attached to the same diacid reactant used in the diester lubricant base oil, and is prepared through an esterification reaction. The charge control agent is then dissolved in the lubricant base oil. The charge control agent is soluble in the lubricant, and is resistant to free radical oxidation. The charge control agent effectively controls the charge of the lubricant by creating electron donor/acceptor sites in the lubricant, facilitating an independent electronic pathway through the lubricant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.