Patent ID: 7597973

Claim:
A magnetic disk adapted to be loaded in a magnetic disk apparatus of a load unload system, comprising: a disk substrate; a magnetic layer formed over the disk substrate; a carbon-based protection layer formed on the magnetic layer; an alcohol-based coupling layer containing only alcohol and formed on a carbon-based protection layer, an alcohol-based coupling layer having a first hydroxyl group; and a lubrication layer formed on the an alcohol-based coupling layer, the lubrication layer containing a hydroxyl-modified perfluoropolyether compound having a second hydroxyl group at a terminal end; wherein hydrogen bond is formed between the second hydroxyl group of the lubrication layer and the first hydroxyl group of the alcohol-based coupling layer to produce coupling force by the hydrogen bond between the carbon-based protection layer and the lubrication layer, wherein a bonded ratio of the lubrication layer for the carbon-based protection layer is not smaller than 70% by interposing the alcohol-based coupling layer between the carbon-based protection layer and the lubrication layer.