公开(公告)号：JPH0620822A

公开(公告)日：1994-01-28

申请号：JP6172093

申请日：1993-03-22

Applicant: BASF AG

Inventor： KURAUDEIUSU KORUMAN ,  ETSUKEHARUTO SHIYUBUAPU ,  MARUTEIN RAUN

IPC: H01F1/34 ,  H01F1/44

Abstract: PURPOSE: To provide a dilatant suspension stable with respect to sedimentation with a wide range of effects on viscosity from an external magnetic field, moreover capable of being affected by a variable, regardless of the suspension. CONSTITUTION: This magnetic dilatant suspension is composed of magnetic particles provided with a particle size smaller than 1 μm, a dispersant material and a solvent provided with the boiling point of at least 100 deg.C, is stable with respect to sedimentation and indicates the magnetic rheological effect of at least 500 Pa measured in the magnetic field of 100 kA/m.

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：JPH0271502A

公开(公告)日：1990-03-12

申请号：JP31663788

申请日：1988-12-16

Applicant: BASF AG

Inventor： MIHIYAERU BUORUFUGANGU MIYURAA ,  KURAUSUUDEIITAA HOTSUPE ,  ETSUKEHARUTO SHIYUBUAPU ,  BUERUNAA SHIYUTETSUKU ,  HERUMUUTO AUBUETAA ,  RAINAA FUEZAA

IPC: B22F9/20 ,  B22F9/22 ,  G11B5/706 ,  H01F1/047 ,  H01F1/06

Abstract: PURPOSE: To enhance a packing density by incorporating a specific amount or less of nickel in an overall amount of metal particles and simultaneously incorporating a specific value or more of magnetization. CONSTITUTION: The needle-like ferromagnetic metal particles made mainly of iron comprises less than 0.4wt.% of nickel to overall amount of the particles, simultaneously more than 100kA of coercive force magnetic field strength and 120nTm /g or more of magnetization measured by 160kA/m of external magnetic field, zinc, phosphorus and silicon in addition to iron and oxygen and less than 0.1wt.% of nickel to overall amount of the particles. The method for manufacturing the particles comprises the steps of precipitating shape stabilized α-FeOOH, heat treating the α-FeOOH at 500 to 850 deg.C for 30 to 300min, and subsequently reducing the obtained material at 200 to 450 deg.C by using gaseous reducing agent. Thus, the reduction of iron oxide material is simplified by nickel catalytic effect, and magnetic characteristics necessary for high packing density of a magnetic recording carrier of the iron particles can be obtained.

公开(公告)号：JPH07150085A

公开(公告)日：1995-06-13

申请号：JP19048394

申请日：1994-08-12

Applicant: BASF AG

Inventor： KURAUDEIUSU KORUMAN ,  ETSUKEHARUTO SHIYUBUAPU ,  ETSUKEHARUTO ZUIN ,  ROBERUTO MIYURAA ,  PEETAA GERUNERUTO

IPC: A61K49/18 ,  B01F17/52 ,  C09D5/23 ,  C09D11/00 ,  C09D11/02 ,  G11B5/842 ,  H01F1/44

公开(公告)号：JPH05140492A

公开(公告)日：1993-06-08

申请号：JP11869892

申请日：1992-05-12

Applicant: BASF AG

Inventor： KURAUDEIUSU KORUMAN ,  ETSUKEHARUTO SHIYUBUAPU ,  FURIIDORITSUHIIBUIRUHERUMU RAU ,  KARIN HAIDORUMU BETSUKU

IPC: C09D11/00 ,  C09D5/23 ,  C09D11/02 ,  C09D11/10 ,  H01F1/44 ,  H01F41/02 ,  H01F41/16

公开(公告)号：JPH07150084A

公开(公告)日：1995-06-13

申请号：JP19048294

申请日：1994-08-12

Applicant: BASF AG

Inventor： KURAUDEIUSU KORUMAN ,  ETSUKEHARUTO SHIYUBUAPU ,  ANGEERIKA FUNHOFU ,  DEIITAA BETSUKU ,  MATEIASU KURONAA

IPC: A61K49/18 ,  B01F17/52 ,  C09D5/23 ,  C09D11/00 ,  C09D11/02 ,  G11B5/70 ,  H01F1/44

公开(公告)号：JPH03132002A

公开(公告)日：1991-06-05

申请号：JP25436890

申请日：1990-09-26

Applicant: BASF AG

Inventor： MIHIYAERU BUORUFUGANGU MIYURAA ,  ETSUKEHARUTO SHIYUBUAPU ,  FUORUKAA ARUNTO

IPC: C01G49/00 ,  G11B5/706 ,  H01F1/11

Abstract: PURPOSE: To increase space-time yield by dissolving ferrite formation metal ion salt into its water of crystallization and then adding the mixture to a water- based alkali liquid and performing autoclave treatment. CONSTITUTION: For example, 3.46mol Fe(No3 )3 .9H2 O, 0.305mol SnCl4 .5H2 O, 0.305mol Co(No3 )2 .6H2 O, and 0.41mol Ba(OH)2 .8H2 O are heated, and dissolved at 50 deg.C. Then, the melted body is agitated and added into a solution, in which 19.5mol NaOH is dissolved into 2037ml water, at 10 deg.C. Then, the suspension liquid is heated in a non-agitated autoclave at 250 deg.C for five hours, is held for five hours, and then is cooled, filtered, washed, dried, and heated at 800 deg.C for 1 hour, thus achieving a 7.5g/l/h space-time yield.

公开(公告)号：JPH0689357A

公开(公告)日：1994-03-29

申请号：JP8343993

申请日：1993-04-09

Applicant: BASF AG

Inventor： KURAUDEIUSU KORUMAN ,  ETSUKEHARUTO SHIYUBUAPU ,  GEERUHARUTO ZEERINGU ,  ROORANDO JIYON BUAICHI

IPC: B42D15/10 ,  G06K7/08 ,  G11B5/02

Abstract: PURPOSE: To provide an excellent method and device which can detect and decode the low retentivity ink Printed document. CONSTITUTION: This method detects and decodes the low retentivity ink printed document. formed by using the magnetic ink that substantially consists of the super paramagnetic solid powder suspension and a substance suspended in water or alcohol. The method tunes to an oscillator 2 which oscillates at a frequency between 10kHz and 10MHz, changes the dielectric constant of a magnetic head 1 where a slit 3 is formed in 5 to 1000μm width by a super paramagnetic material that forms the ink printed document, and records the frequency change caused by the said dielectric constant change as the informational document.

公开(公告)号：JPH05205930A

公开(公告)日：1993-08-13

申请号：JP24029292

申请日：1992-09-09

Applicant: BASF AG

Inventor： KURAUDEIUSU KORUMAN ,  ETSUKEHARUTO SHIYUBUAPU ,  MARUTEIN RAUN

IPC: H01F1/34 ,  G01N11/14 ,  H01F1/28 ,  H01F1/37 ,  H01F1/44

Abstract: PURPOSE: To provide a magnetic-rheological fluid, which does not exhibit corro sive action, contains stable liquid medium and magnetic powder, even at either of a high temperature or a low temperature, indicates high magnetic-rheological effect and low basic viscosity, low abrasion, short switching time and good settling stability. CONSTITUTION: This liquid contains magnetic powder, which is covered with the macro-molecular electrolyte having the molecular weight from 500-250,000 and has particle size smaller than 1μm, and wherein the polar solvent having the boiling point not lower than 100 deg.C is suspended. This is the magnetic- rheological liquid, indicating the magnetic-rheological effect that is larger than 100Pa and up to 10,000Pa, measured in the magnetic field of 100kA/m.

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.