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FR2138160A1 - Ferromagnetic chromium dioxide prepn by two stages - heating chromium trioxide with tellurium cpd - Google Patents

Ferromagnetic chromium dioxide prepn by two stages - heating chromium trioxide with tellurium cpd

Info

Publication number
FR2138160A1
FR2138160A1 FR7218148A FR7218148A FR2138160A1 FR 2138160 A1 FR2138160 A1 FR 2138160A1 FR 7218148 A FR7218148 A FR 7218148A FR 7218148 A FR7218148 A FR 7218148A FR 2138160 A1 FR2138160 A1 FR 2138160A1
Authority
FR
France
Prior art keywords
pref
atm
degrees
cpd
heating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
FR7218148A
Other languages
French (fr)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bayer AG
Original Assignee
Bayer AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bayer AG filed Critical Bayer AG
Publication of FR2138160A1 publication Critical patent/FR2138160A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09CTREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/34Compounds of chromium
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62Record carriers characterised by the selection of the material
    • G11B5/68Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
    • G11B5/70Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
    • G11B5/706Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material
    • G11B5/70626Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances
    • G11B5/70636CrO2

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Pigments, Carbon Blacks, Or Wood Stains (AREA)
  • Hard Magnetic Materials (AREA)

Abstract

Ferromagnetic CrO2 modified with telluric acid is prepd. by (a) heating CrO3 in the presence of water and >=1 finely divided cpd. of formula: A2TeO6 (where A is Cr, Fe, Al, Ga and/or Mn) which is in the form of a rutile or trirutile lattice, at 100-300 degrees C pref. 200-300 degrees C under a pressure of 1-500 atm. pref. 50-300 atm. to form CrO2 mixed phase cores, and (b) hydrothermally converting the cores with further CrO3 and water at 100-450 degrees C pref. 280-420 degrees C under a pressure of 1-500 atm. pref. 100-400 atm. Used for magnetic impulse registration and reproduction, e.g. on magnetic tapes and drums. Material has excellent magnetic props., esp. a high value of the remanence of coercive force, and favourable particle size.
FR7218148A 1971-05-19 1972-05-19 Ferromagnetic chromium dioxide prepn by two stages - heating chromium trioxide with tellurium cpd Withdrawn FR2138160A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19712124812 DE2124812A1 (en) 1971-05-19 1971-05-19 Process for the production of ferromagnetic chromium dioxide

Publications (1)

Publication Number Publication Date
FR2138160A1 true FR2138160A1 (en) 1972-12-29

Family

ID=5808310

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7218148A Withdrawn FR2138160A1 (en) 1971-05-19 1972-05-19 Ferromagnetic chromium dioxide prepn by two stages - heating chromium trioxide with tellurium cpd

Country Status (5)

Country Link
BE (1) BE783763A (en)
DE (1) DE2124812A1 (en)
FR (1) FR2138160A1 (en)
IT (1) IT957902B (en)
NL (1) NL7206854A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0001524A1 (en) * 1977-10-04 1979-04-18 ANVAR Agence Nationale de Valorisation de la Recherche Novel ferromagnetic material based on chromium dioxide and rhodium dioxide, and its preparation
FR2405220A1 (en) * 1977-10-04 1979-05-04 Anvar Ferromagnetic cpd. with improved magnetic properties - consists of a solid soln. of chromium di:oxide and rhodium di:oxide
EP0007764A1 (en) * 1978-07-21 1980-02-06 Montedison S.p.A. Stabilized ferromagnetic chromium dioxide and a process for preparing it
FR2433483A2 (en) * 1978-08-18 1980-03-14 Anvar Ferromagnetic cpd. with improved magnetic properties - consists of a solid soln. of chromium di:oxide and rhodium di:oxide
FR2502384A1 (en) * 1981-03-17 1982-09-24 Centre Nat Rech Scient NEW FERROMAGNETIC MATERIAL BASED ON CHROMIUM AND IRIDIUM, ITS OBTAINING AND APPLICATION AS RECORDING MATERIAL
EP0146127A3 (en) * 1983-12-16 1987-06-16 E.I. Du Pont De Nemours And Company Controlled initiation chromium dioxide synthesis

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109467433B (en) * 2018-12-14 2021-03-30 电子科技大学 Co-Ti-Ta-based dielectric ceramic material and preparation method thereof

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0001524A1 (en) * 1977-10-04 1979-04-18 ANVAR Agence Nationale de Valorisation de la Recherche Novel ferromagnetic material based on chromium dioxide and rhodium dioxide, and its preparation
FR2405220A1 (en) * 1977-10-04 1979-05-04 Anvar Ferromagnetic cpd. with improved magnetic properties - consists of a solid soln. of chromium di:oxide and rhodium di:oxide
US4311770A (en) * 1977-10-04 1982-01-19 Agence Nationale De Valorisation De La Recherche (Anvar) Novel ferromagnetic chromium dioxide and rhodium dioxide material and its preparation
EP0007764A1 (en) * 1978-07-21 1980-02-06 Montedison S.p.A. Stabilized ferromagnetic chromium dioxide and a process for preparing it
FR2433483A2 (en) * 1978-08-18 1980-03-14 Anvar Ferromagnetic cpd. with improved magnetic properties - consists of a solid soln. of chromium di:oxide and rhodium di:oxide
FR2502384A1 (en) * 1981-03-17 1982-09-24 Centre Nat Rech Scient NEW FERROMAGNETIC MATERIAL BASED ON CHROMIUM AND IRIDIUM, ITS OBTAINING AND APPLICATION AS RECORDING MATERIAL
EP0146127A3 (en) * 1983-12-16 1987-06-16 E.I. Du Pont De Nemours And Company Controlled initiation chromium dioxide synthesis

Also Published As

Publication number Publication date
DE2124812A1 (en) 1972-11-30
NL7206854A (en) 1972-11-21
BE783763A (en) 1972-11-20
IT957902B (en) 1973-10-20

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Legal Events

Date Code Title Description
RE Withdrawal of published application