公开(公告)号：JP2001351221A

公开(公告)日：2001-12-21

申请号：JP2001108293

申请日：2001-04-06

Applicant: EMTEC MAGNETICS GMBH

Inventor： JAKUSCH HELMUT DR ,  KOHL ALBERT ,  HEILMANN PETER DR ,  VEITCH RONALD JOHN ,  KRESS RIA ,  MUELLER STEFAN ,  SANDROCK JOHANNES ,  HEENE HARTMUT

IPC: G11B5/667 ,  G11B5/70 ,  G11B5/706 ,  G11B5/708 ,  G11B5/712 ,  G11B5/714 ,  G11B5/716 ,  G11B5/842

Abstract: PROBLEM TO BE SOLVED: To provide a magnetic recording medium which uses pigment in the lower side layer, which is markedly characterized in that it is every finely pulverized, more economical than the conventional pigment in the lower side layer and magnetically soft. SOLUTION: A multilayered magnetic recording medium, suitable for high recording density and digital recording, having superior electromagnetic recording characteristics and improved surface smoothness and capable of sufficiently absorbing a large quantity of lubricant in the lower side layer, is provided with an upper-side magnetic recording layer, having less than 0.5 μm layer thickness and at least one layer of lower side layer which includes the magnetically soft pigment.

公开(公告)号：DE10017490A1

公开(公告)日：2001-10-11

申请号：DE10017490

申请日：2000-04-07

Applicant: EMTEC MAGNETICS GMBH

Inventor： JAKUSCH HELMUT ,  VEITCH RONALD ,  KOHL ALBERT ,  KRESS RIA ,  SANDROCK JOHANNES ,  MUELLER STEFAN ,  HEENE HARTMUT ,  HEILMANN PETER

IPC: G11B5/667 ,  G11B5/70 ,  G11B5/706 ,  G11B5/708 ,  G11B5/712 ,  G11B5/714 ,  G11B5/716 ,  G11B5/842 ,  G11B5/68 ,  C01G49/02 ,  B32B15/08

Abstract: Magnetic recording medium comprises an upper magnetic recording layer of thickness of less than 0.5 mu m containing a fine magnetic pigment having a coercive force of 100-250 kA/m on a non-magnetic carrier; and a lower isotropic soft magnetic layer made from psi -Fe2O3, Fe3O4 or a mixed crystal of the two. The average crystal size of the lower layer is less than 10 nm. An Independent claim is also included for a process for the production of a magnetic recording medium. Preferred Features: The magnetic pigment in the upper layer is a metal pigment or a metal alloy pigment, preferably a hexagonal ferrite pigment or a Co-modified psi -Al2O3, Co-modified Fe3O4 or a mixed crystal of these. The soft magnetic pigment in the lower layer is made from an aluminum compound and/or a silicon compound.