Patent ID: 8007932
Filing Date: 2011-08-30
Classification: G11B

Abstract:
1. A magnetic disk comprising: a magnetic layer; a protective layer; and a lubricating layer, formed over a non-magnetic substrate, and wherein said lubricating layer is composed of a lubricant containing a first ingredient and a second ingredient, said first ingredient as the main constituent being a first perfluoropolyether compound represented by the formula (1) which has a weight-average molecular weight of 500 to 6000 and a dispersity smaller than 1.3, and said second ingredient being a second perfluoropolyether compound which has a weight-average molecular weight of 500 to 6000 and has 6 to 10 hydroxyl groups (on average) in one molecule, where, Rf where, m and n each denote a natural number,