公开(公告)号：JPH01270520A

公开(公告)日：1989-10-27

申请号：JP5024289

申请日：1989-03-03

Applicant: BASF AG

Inventor： FUORUKAA ARUNTO ,  HERUMUUTO AUBUETAA ,  RAINAA FUEZAA ,  ETSUKEHARUTO SHIYUBUAPU

IPC: C01G49/06 ,  G11B5/706 ,  H01F1/11

公开(公告)号：JPH01219024A

公开(公告)日：1989-09-01

申请号：JP59689

申请日：1989-01-06

Applicant: BASF AG

Inventor： DEIITAA SHIYUTOTSUKUBURUGAA ,  RAINAA FUEZAA ,  ZAFUIRIOSU GURAMATEISU ,  NORUBERUTO MIYURAA ,  MANFUREETO OORINGAA ,  HERUMUUTO RAINITSUKE ,  KAARUUHAINTSU ZARUTOORU ,  HAINTSU SHIYURINTOBUAIN ,  BUERUNAA SHIYUTETSUKU

IPC: C01G37/02 ,  C01G37/027

公开(公告)号：JPS6472923A

公开(公告)日：1989-03-17

申请号：JP20850088

申请日：1988-08-24

Applicant: BASF AG

Inventor： BERUNTO MAIYAA ,  BUERUNAA SHIYUTETSUKU ,  BERUNHARUTO BETOHIYAA ,  HERUMUUTO YAKUSHIYU ,  RAINAA FUEZAA

IPC: C01G37/02 ,  C01G37/027 ,  G11B5/706 ,  H01F1/10

公开(公告)号：JP2582764B2

公开(公告)日：1997-02-19

申请号：JP2263987

申请日：1987-02-04

Applicant: BASF AG

Inventor： KURAUSUUDEIITAA HOPE ,  UERUNAA SHUTETSUKU ,  IEENE KOFUAKUSU ,  RAINAA FUEZAA ,  HERUMUUTO YAKUSHU

IPC: B22F9/20 ,  B22F9/22 ,  C01G49/06 ,  G11B5/706 ,  G11B5/712 ,  H01F1/06

公开(公告)号：JP2512721B2

公开(公告)日：1996-07-03

申请号：JP21738386

申请日：1986-09-17

Applicant: BASF AG

Inventor： UERUNAA SHUTETSUKU ,  RASUTSURO MAROZUI ,  HERUBERUTO HAABAAKORUN ,  RAINAA FUEZAA ,  UERUNAA HYUUBUNAA ,  HERUMUUTO YAKUSHU

IPC: H01F1/11 ,  C01G37/027 ,  G11B5/706

公开(公告)号：JPH02256203A

公开(公告)日：1990-10-17

申请号：JP28316489

申请日：1989-11-01

Applicant: BASF AG

Inventor： MIHIYAERU BUORUFUGANGU MIYURAA ,  ETSUKEHARUTO SHIYUBUAPU ,  HERUMUUTO AUBUETAA ,  RAINAA FUEZAA ,  RUDEI REENERUTO ,  NORUBERUTO MIYURAA ,  MANFUREETO OORINGAA

IPC: C01G49/00 ,  C01G37/027 ,  C09D5/23 ,  C09D7/12 ,  G11B5/706 ,  H01F1/11

Abstract: PURPOSE: To obtain needle-like ferromagnetic chromium dioxide material showing high coercive force field strength and a high saturation magnetization value by a method wherein water-containing chrome acid chrome III is heated up to the temperature of 200 to 500 deg.C in a high pressure reactor, and immediately after reaction to this temperature, the material is cooled down and the pressure of the high pressure reactor is relaxed. CONSTITUTION: Hydrous chrome acid chrome III, having the degree of hydration n of at leas 13 in the form of Cr2 (CrO4 )3 .nH2 O is decomposed at the temperature of 200 to 500 deg.C under the pressure of 50 to 700var. To be more precise, the hydrous chrome acid chrome III is heated up to 200 to 500 deg.C in a high pressure reactor, and after said temperature is attained, the material is cooled down immediately and the pressure of the reactor is relaxed. Accordingly, in the needle-like ferromagnetic material consisting of iron-containing chromium dioxide and containing the indium smaller than 2ppm and the cobalt smaller than 50ppm as the component of chromium dioxide, upon measurement in a magnetic field of 380kA/m, a ferromagnetic material, having a coercive field intensity higher than 61kA/m, can be obtained when a magnetizing operation of 70nTm /g or higher is conducted.

公开(公告)号：JPH02106002A

公开(公告)日：1990-04-18

申请号：JP21023989

申请日：1989-08-16

Applicant: BASF AG

Inventor： MIHIYAERU BUORUFUGANGU MIYURAA ,  ETSUKEHARUTO SHIYUBUAPU ,  HERUMUUTO AUBUETAA ,  RAINAA FUEZAA ,  BUERUNAA HIYUBUNAA ,  NORUBERUTO MIYURAA ,  MANFUREETO OORINGAA ,  HERUMAN DEIKOBU

IPC: C01G37/027 ,  C09D5/23 ,  C09D7/12 ,  G11B5/706 ,  H01F1/11

Abstract: PURPOSE: To improve storage stability, by using a specific chromium dioxide material constructed by needle-shaped ferromagnetic chromium dioxide powders having a non-magnetic hydrogen contained surface protective layer. CONSTITUTION: A chromium dioxide material constructed by needle-shaped ferromagnetic chromium dioxide powders, having a non-magnetic hydrogen contained surface protective layer, and showing a saturation magnetization larger than 80nTm /G at the Z200 value smaller than 0.85ppm, is used. The chromium dioxide material is produced by using a special transforming agent containing mainly antimony, selenium, tellurium and/or iron, or a compound of them. Thus, the chromium dioxide material having especially preferable magnetic characteristics and a narrow particle size distribution can be obtained, and deterioration due to heat and moisture of the magnetic characteristics can be improved.

公开(公告)号：JPS63307120A

公开(公告)日：1988-12-14

申请号：JP12724588

申请日：1988-05-26

Applicant: BASF AG

Inventor： NORUBERUTO MIYURAA ,  MANFUREETO OORINGAA ,  RAINAA FUEZAA ,  BERUNHARUTO BETOHIYAA ,  PEETAA RUDORUFU ,  BUERUNAA HIYUPUNAA

IPC: C01G37/027 ,  G11B5/706 ,  H01F1/11