Patent ID: 8709532

Claim:
A manufacturing method of a magnetic disk having a magnetic layer, a protection layer, and a lubrication layer formed on a substrate in this order, comprising the steps of: forming said lubrication layer as a film of a perfluoropolyether compound having a flexible main chain portion containing fluorine and polar groups at ends of the main chain, the polar groups comprising first polar groups within said lubrication layer, having unexposed ends and being oriented towards said protection layer, and second polar groups that are exposed on a surface of said lubrication layer; and immediately after forming said lubrication layer, treating a surface of said magnetic disk by the use of a composition containing hydrofluoroether after formation of said lubrication layer such that a film of hydrofluoroether is formed on the surface of said magnetic disk such that the second polar groups have ends that are bonded to ether bond groups, due to contact by the hydrofluoroether with the surface of the lubrication layer to cover and inactivate the exposed polar groups.