Patent · US Expired

Hard disk drive utilizing second lubricant over a first lubricant having a phosophezine group

US6816341B2 · kind B2 · utility

4Cited by
4References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 22, 2003
Grant dateNov 9, 2004
Priority date
Expiry dateApr 30, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/265
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A recording element or a reproducing element in a head generates heat that decomposes lubricating agent adhered to a slider surface near the recording/reproducing element of the head. This decomposed lubricating agent leads to corrosion of the magnetic layer and the like of the magnetic disk. The lubricating agent undergoes volume expansion due to this corrosion, creating a protrusion on the magnetic disk surface to which the lubricating agent is adhered. The magnetic disk surface to which the lubricating agent is adhered comes into contact with the magnetic head, leading to friction with the protective layer, the magnetic layer, and the like. In the worst case, this can lead to secondary errors where data recorded on the magnetic layer is erased. To prevent such secondary errors, the present invention provides a hard disk drive including:a magnetic disk to which is applied a first lubricating agent formed as (where p=0 or an integer of at least 1, q=0 or an integer of at least 1, and X=1-5); anda mechanism for supplying a second lubricating agent to the magnetic disk having an average molecular weight of no more than 2,400 and no less than 600 and formed asHOCH2CF2(OC2F4)p(OCF2)qO…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.