Magnetic disk
AssigneeHoya Corporation
InventorsHiroshi Tomiyasu, Koichi Shimokawa
Life of this patent
Estimating the term…
Abstract
Disclosed is a magnetic disk which has a lubricant layer with excellent heat resistance and high adhesiveness and is free from fly-stiction failure or corrosion failure even at an extremely low flying height of 10 nm or lower. Also disclosed is a magnetic disk which has a lubricant layer with good thermal properties and can exert a stable action over a wide temperature range. The magnetic disk comprises a substrate (1), and a magnetic layer (3), a carbon-containing protective layer (4) and a lubricant layer (5) provided on the substrate (1), wherein the lubricant layer (5) contains a magnetic disk lubricant comprising a compound having a phosphazene ring and two or more hydroxyl and/or carboxyl groups in the molecule.
Claims6
A magnetic disk having a magnetic layer, a carbon-based protective layer, and a lubricating layer over a substrate, wherein:
- the lubricating layer contains a magnetic disk lubricant comprising a compound having a phosphazene ring and two or more hydroxyl and/or carboxyl groups (if a group having a hydroxyl group is bonded to one of bonds of the phosphazene ring, the compound has three or more hydroxyl groups) in one molecule.
A magnetic disk having a magnetic layer, a carbon-based protective layer, and a lubricating layer over a substrate, wherein:
- the lubricating layer contains a phosphazene compound represented by a general formula (I)
- (in the formula, each of R1 to R6 is a fluorine-containing group, a hydroxyl group, or a carboxyl group, at least one of R1 to R6 is a group having —(O—C2F4)m-(O—CF2)n- (m and n are each an integer of 1 or more) in a structure thereof and having a hydroxyl group and/or a carboxyl group at terminals/a terminal thereof, and the phosphazene compound has two or more hydroxyl and/or carboxyl groups in one molecule, while, if one of R1 to R6 is a group having —(O—C2F4)m-(O—CF2)n- (m and n are each an integer of 1 or more) in a structure thereof and having a hydroxyl group at a terminal thereof, the phosphazene compound has three or more hydroxyl groups at terminals thereof).
Dependencies are inferred from the claim text.