公开(公告)号：JPH0573880A

公开(公告)日：1993-03-26

申请号：JP25417991

申请日：1991-09-06

Applicant: IBM

Inventor： SHIMIZU TERUHISA ,  TAKAYAMA SHINJI

IPC: G11B5/66 ,  G11B5/64 ,  G11B5/65 ,  G11B5/85 ,  G11B5/851

Abstract: PURPOSE: To provide a magnetic recording medium which is low in medium noise, has high coercive force and is adequate for longitudinal recording. CONSTITUTION: The magnetic recording medium includes a substrate 1 and a magnetic layer 2 formed on this substrate 1. The magnetic layer 2 is constituted by mixing a magnetic material which is any of a Co system, Fe system and FeCO system and at least one kind of nonmagnetic compds. which are selected from a group consisting of oxide and nitride. The ratio of the volume of the nonmagnetic compd. occupying the entire volume of the magnetic material and the nonmagnetic materials to be mixed is preferably about >=2 about

公开(公告)号：JPH03108144A

公开(公告)日：1991-05-08

申请号：JP24242289

申请日：1989-09-20

Applicant: IBM

Inventor： KATOU YOSHIMINE ,  SHIMIZU TERUHISA ,  TAKAYAMA SHINJI ,  TANAKA HIROSHI

IPC: G11B11/10 ,  G11B11/105

Abstract: PURPOSE: To attain high-density recording by laminating at least one layer each of a first magnetic layer and second magnetic layer consisting of rare earth-transition metal amorphous films on a substrate and increasing the intensity of the magnetic anisotropy in the direction perpendicular to the film plane. CONSTITUTION: This magneto-optical recording medium is formed by laminating at least one layer each of the first magnetic layer 1 and second magnetic layer 2 consisting of the rare earthtransition metal amorphous films on the substrate 3. The magnetic layer 1 is the one element selected from an element group consisting of Nd and Pr. The magnetic layer 2 contains only one element selected from an element group consisting of Tb and Dyb. The magnetic layer 1 has a high magneto-optical effect at a short wavelength and small perpendicular magnetic anisotropy. The magnetic layer is conversely small in the magnet optical effect and large in the perpendicular magnetic anisotropy. When the magnetic layers 1, 2 are laminated, the magnetic interlayer bonding effect generated between the two layers is exerted on the magnetic layer 1. The medium of the perpendicularly magnetized films having the high magneto-optical effect even at a short wavelength over the entire part of the laminated layers is then obtd. and high-density recording is made possible.

公开(公告)号：DE69222823D1

公开(公告)日：1997-11-27

申请号：DE69222823

申请日：1992-08-25

Applicant: IBM

Inventor： SHIMIZU TERUHISA ,  TAKAYAMA SHINJI

IPC: G11B5/66 ,  G11B5/64 ,  G11B5/65 ,  G11B5/85 ,  G11B5/851

Abstract: A magnetic recording medium includes a substrate 1 and a magnetic layer 2 formed on the substrate 1. The magnetic layer 2 consists of a mixture of a magnetic alloy and a non-magnetic compound. The magnetic alloy is Co-based, Fe-based, or CoFe-based, and the non-magnetic compound is selected from a group consisting of oxides and nitrides. The volume percentage of the non-magnetic compound in the entire volume of the mixed magnetic alloy and non-magnetic compound is preferably between about 2% and about 30%. The magnetic recording disk is suitable for longitudinal recording, with low medium noise and high coercivity.

公开(公告)号：HK24096A

公开(公告)日：1996-02-16

申请号：HK24096

申请日：1996-02-08

Applicant: IBM

Inventor： KATO YOSHIMINE ,  SHIMIZU TERUHISA ,  TAKAYAMA SHINJI ,  TANAKA HIROSHI

IPC: G11B11/10 ,  G11B11/105 ,  G11B7/24

Abstract: A magneto-optical recording medium is provided which has high magneto-optic effect even under a short-wavelength light, high anisotropy in the direction perpendicular to the film surface, and permits high-density recording, the medium having a first magnetic layer laminated onto a second magnetic layer, the first magnetic layer being a rare-earth-transition-metal amorphous film with mainly a light rare-earth element as rare-earth element, the light rare-earth element being at least one element selected from an element group consisting of Nd and Pr, and the second magnetic layer being a rare-earth-transition-metal amorphous film with at least one element selected from an element group consisting of Tb and Dy as rare-earth element.

公开(公告)号：CA2071348C

公开(公告)日：1998-05-19

申请号：CA2071348

申请日：1992-06-16

Applicant: IBM

Inventor： SHIMIZU TERUHISA ,  TAKAYAMA SHINJI

IPC: G11B5/66 ,  G11B5/64 ,  G11B5/65 ,  G11B5/85 ,  G11B5/851 ,  G11B5/706 ,  G11B5/708

Abstract: This disclosure deals with a magnetic recording medium suitable for longitudinal recording, such medium having low medium noise and high coercivity. The medium includes a substrate and a magnetic layer formed on the substrate. The magnetic layer consists of a mixture of a magnetic alloy and a non-magnetic compound. The magnetic alloy is based on Co, Fe, or, Co-Fe, and the non-magnetic compound is selected from a group of oxides and nitrides such as, for example, silicon, zirconium, tantalum, boron, titanium and aluminum. The volume percentage of the non-magnetic compound in the entire volume of the mixed magnetic alloy and non-magnetic compound is preferably not less than about 2% and not more than about 30%.

公开(公告)号：SG44396A1

公开(公告)日：1997-12-19

申请号：SG1996000135

申请日：1992-08-25

Applicant: IBM

Inventor： SHIMIZU TERUHISA ,  TAKAYAMA SHINJI

IPC: G11B5/66 ,  G11B5/64 ,  G11B5/65 ,  G11B5/85 ,  G11B5/851

Abstract: A magnetic recording medium includes a substrate 1 and a magnetic layer 2 formed on the substrate 1. The magnetic layer 2 consists of a mixture of a magnetic alloy and a non-magnetic compound. The magnetic alloy is Co-based, Fe-based, or CoFe-based, and the non-magnetic compound is selected from a group consisting of oxides and nitrides. The volume percentage of the non-magnetic compound in the entire volume of the mixed magnetic alloy and non-magnetic compound is preferably between about 2% and about 30%. The magnetic recording disk is suitable for longitudinal recording, with low medium noise and high coercivity.

公开(公告)号：DE69020992D1

公开(公告)日：1995-08-24

申请号：DE69020992

申请日：1990-09-17

Applicant: IBM

Inventor： KATO YOSHIMINE ,  SHIMIZU TERUHISA ,  TAKAYAMA SHINJI ,  TANAKA HIROSHI

IPC: G11B11/10 ,  G11B11/105 ,  G11B7/24

Abstract: A magneto-optical recording medium is provided which has high magneto-optic effect even under a short-wavelength light, high anisotropy in the direction perpendicular to the film surface, and permits high-density recording, the medium having a first magnetic layer laminated onto a second magnetic layer, the first magnetic layer being a rare-earth-transition-metal amorphous film with mainly a light rare-earth element as rare-earth element, the light rare-earth element being at least one element selected from an element group consisting of Nd and Pr, and the second magnetic layer being a rare-earth-transition-metal amorphous film with at least one element selected from an element group consisting of Tb and Dy as rare-earth element.

公开(公告)号：DE69020992T2

公开(公告)日：1996-04-04

申请号：DE69020992

申请日：1990-09-17

Applicant: IBM

Inventor： KATO YOSHIMINE ,  SHIMIZU TERUHISA ,  TAKAYAMA SHINJI ,  TANAKA HIROSHI

IPC: G11B11/10 ,  G11B11/105 ,  G11B7/24

Abstract: A magneto-optical recording medium is provided which has high magneto-optic effect even under a short-wavelength light, high anisotropy in the direction perpendicular to the film surface, and permits high-density recording, the medium having a first magnetic layer laminated onto a second magnetic layer, the first magnetic layer being a rare-earth-transition-metal amorphous film with mainly a light rare-earth element as rare-earth element, the light rare-earth element being at least one element selected from an element group consisting of Nd and Pr, and the second magnetic layer being a rare-earth-transition-metal amorphous film with at least one element selected from an element group consisting of Tb and Dy as rare-earth element.

公开(公告)号：CA2017300C

公开(公告)日：1994-05-17

申请号：CA2017300

申请日：1990-05-22

Applicant: IBM

Inventor： KATO YOSHIMINE ,  SHIMIZU TERUHISA ,  TAKAYAMA SHINJI ,  TANAKA HIROSHI

IPC: G11B11/10 ,  G11B11/105 ,  G11C13/06

Abstract: A magneto-optical recording medium has a first magnetic layer laminated on a second magnetic layer, the first magnetic layer, of (Nd, Pr)-transition-metal amorphous alloy systems, having high magneto-optical effect at short wavelengths but low perpendicular anisotropy, and the second magnetic layer, of (Tb, Dy)-transition-metal amorphous alloy systems, having low magneto-optical effect at short wavelengths but low perpendicular anisotropy. By exerting magnetic exchange coupling between these two layers on the said first layer to induce strong perpendicular anisotropy in it, a perpendicular magnetized magneto-optical recording medium is obtained that has overall high magneto-optical effect, even at short wavelengths.

公开(公告)号：CA2071348A1

公开(公告)日：1993-03-07

申请号：CA2071348

申请日：1992-06-16

Applicant: IBM

Inventor： SHIMIZU TERUHISA ,  TAKAYAMA SHINJI

IPC: G11B5/66 ,  G11B5/64 ,  G11B5/65 ,  G11B5/85 ,  G11B5/851 ,  G11B5/706 ,  G11B5/708

Abstract: A magnetic recording medium includes a substrate 1 and a magnetic layer 2 formed on the substrate 1. The magnetic layer 2 consists of a mixture of a magnetic alloy and a non-magnetic compound. The magnetic alloy is Co-based, Fe-based, or CoFe-based, and the non-magnetic compound is selected from a group consisting of oxides and nitrides. The volume percentage of the non-magnetic compound in the entire volume of the mixed magnetic alloy and non-magnetic compound is preferably between about 2% and about 30%. The magnetic recording disk is suitable for longitudinal recording, with low medium noise and high coercivity.