公开(公告)号：US09767835B2

公开(公告)日：2017-09-19

申请号：US15054887

申请日：2016-02-26

申请人： HITACHI MAXELL, LTD.

发明人： Kenji Tanaka ,  Masao Fujita ,  Sadamu Kuse

IPC分类号： G11B5/71 ,  G11B5/714 ,  G11B5/738 ,  G11B5/706 ,  G11B5/78

CPC分类号： G11B5/71 ,  G11B5/70615 ,  G11B5/70626 ,  G11B5/714 ,  G11B5/738 ,  G11B5/78

摘要： A magnetic recording medium of the present invention is a magnetic recording medium including a non-magnetic substrate; a non-magnetic layer that is formed on one of principal surfaces of the non-magnetic substrate and contains a non-magnetic powder, a binder, and a lubricant; and a magnetic layer that is formed on a principal surface of the non-magnetic layer opposite to the non-magnetic substrate and contains a magnetic powder and a binder. The magnetic powder has an average particle size between 10 nm and 35 nm inclusive. The lubricant is migratable to the magnetic layer and forms a lubricant layer on a surface of the magnetic layer when a pressure is applied to the magnetic layer. When spacing of the surface of the magnetic layer before and after washing the lubricant with n-hexane is measured with a TSA (Tape Spacing Analyzer), the value of the spacing after washing is 3 to 10 nm, and the value of the spacing before washing is 1 to 5 nm smaller than the value of the spacing after washing.