Magnetic disk and magnetic disk unit

Abstract

Embodiments of the present invention provide a magnetic disk having a lubricating layer formed on the surface thereof, which meets all the requirements for adhesiveness, adequate flowability, and strong binding power. In a particular embodiment, a magnetic disk has a magnetic layer, a protective layer, and a lubricating layer which are formed on a non-magnetic substrate, which is characterized in that said lubricating layer is comprised 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) below, 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, Rt-Rf1-Rt  (1) where, Rf1 denotes a perfluoropolyether chain represented by the formula (2) and Rt denotes a terminal group represented by the formula (3), —CF2O—[(CF2CF2O)m—(CF2O)n]—CF2—  (2) where, m and n each denote a natural number,

Dependencies are inferred from the claim text.