GB1274880A - Process for the preparation of chromium pentoxide and ferromagnetic chromium dioxide made therefrom - Google Patents

Process for the preparation of chromium pentoxide and ferromagnetic chromium dioxide made therefrom

Info

Publication number
GB1274880A
GB1274880A GB3584869A GB3584869A GB1274880A GB 1274880 A GB1274880 A GB 1274880A GB 3584869 A GB3584869 A GB 3584869A GB 3584869 A GB3584869 A GB 3584869A GB 1274880 A GB1274880 A GB 1274880A
Authority
GB
United Kingdom
Prior art keywords
chromium
curve
pentoxide
dioxide
ferromagnetic
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.)
Expired
Application number
GB3584869A
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.)
RCA Corp
Original Assignee
RCA Corp
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 RCA Corp filed Critical RCA Corp
Publication of GB1274880A publication Critical patent/GB1274880A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
    • G11B5/70—Record 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
    • G11B5/706—Record 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
    • G11B5/70626—Record 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
    • G11B5/70636—CrO2
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G37/00—Compounds of chromium
    • C01G37/02—Oxides or hydrates thereof
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/20—Particle morphology extending in two dimensions, e.g. plate-like
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/51—Particles with a specific particle size distribution
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/54—Particles characterised by their aspect ratio, i.e. the ratio of sizes in the longest to the shortest dimension
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/20—Powder free flowing behaviour
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/42—Magnetic properties

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Magnetic Record Carriers (AREA)

Abstract

1,274,880. Magnetic recording media. RCA CORPORATION. 16 July, 1969 [22 July, 1968], No. 35848/69. Heading H1H. [Also in Division C1] Ferromagnetic chromium dioxide, prepared by the hydrothermal decomposition of an antimony oxide containing aqueous slurry of chromium pentoxide (see Division C1), has an extremely favourable particle size distribution and is used in making magnetic tapes. The dioxide is dispersed in a vinyl copolymer and applied to a polyester base. As curve 1 of Fig. 1 shows the chromium dioxide of the invention has a narrow particle size distribution having almost no particles longer than 0À9 micrometers. Fig. 3 shows in curve 6 a line plot of the data of Fig. 1 using the cumulative frequency of observation as the ordinate. It should be noted that this curve has a linear portion having a slope of 250 microns<SP>-1</SP> which is also diagnostic of the CrO 2 used.
GB3584869A 1968-07-22 1969-07-16 Process for the preparation of chromium pentoxide and ferromagnetic chromium dioxide made therefrom Expired GB1274880A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US74661968A 1968-07-22 1968-07-22

Publications (1)

Publication Number Publication Date
GB1274880A true GB1274880A (en) 1972-05-17

Family

ID=25001622

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3584869A Expired GB1274880A (en) 1968-07-22 1969-07-16 Process for the preparation of chromium pentoxide and ferromagnetic chromium dioxide made therefrom

Country Status (1)

Country Link
GB (1) GB1274880A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004020338A2 (en) * 2002-08-29 2004-03-11 Tata Institute Of Fundamental Research Chromium dioxide (cro2) and composites of chromium dioxide and other oxides of chromium such as cro2/cr2o3 and cro2/cr2o5 and process for manufacturing the same

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004020338A2 (en) * 2002-08-29 2004-03-11 Tata Institute Of Fundamental Research Chromium dioxide (cro2) and composites of chromium dioxide and other oxides of chromium such as cro2/cr2o3 and cro2/cr2o5 and process for manufacturing the same
WO2004020338A3 (en) * 2002-08-29 2004-08-12 Tata Inst Of Fundamental Res Chromium dioxide (cro2) and composites of chromium dioxide and other oxides of chromium such as cro2/cr2o3 and cro2/cr2o5 and process for manufacturing the same
US7276226B2 (en) * 2002-08-29 2007-10-02 Tata Institute Of Fundamental Research Chromium dioxide (CrO2) and composites of chromium dioxide and other oxides of chromium such as CrO2/Cr2O3 and CrO2/Cr2O5) and process for manufacturing the same

Similar Documents

Publication Publication Date Title
US3573980A (en) Method of making magnetic particles and recording tape
KR840008869A (en) Plate-shaped barium ferrite particles for magnetic recording and manufacturing method thereof
GB1095135A (en) A magnetic recording process
US3117093A (en) Process for the preparation of ferromagnetic chromium dioxide
US3725126A (en) Magnetic recording tape
US2822533A (en) Device for reading magnetically recorded memory elements
US3031341A (en) High density magnetic recording tape
GB1513290A (en) Magnetic head cleaning tape and method
CA988704A (en) Ferro-magnetic acicular particles for recording medium
CA965183A (en) High recording density magnetic media with square b-h loop
US3389014A (en) Recording element with magnetic coating containing a mixture of granular and acicularmagnetic particles
GB1384918A (en) Magnetic record medium and method of treating same
CA1007444A (en) Cobalt-containing acicular ferrimagnetic iron oxide of improved remanence stability
GB1441183A (en) Magnetic recording particles
GB1274880A (en) Process for the preparation of chromium pentoxide and ferromagnetic chromium dioxide made therefrom
GB1268458A (en) Improvements in and relating to the preparation of cobalt doped gamma ferric oxide
GB1437978A (en) Preparation of ferromagnetic chromium dioxide
US3243375A (en) Precipitation process for preparing acicular magnetic metal oxide particles
US4699840A (en) Magnetic recording medium
GB996606A (en) Method of preparing a magnetic record member
US3047428A (en) Magnetic recording material
GB1355895A (en) Method of copying magnetic recordings
Middleton The replay signal from a tape with magnetization components parallel and normal to its plane
FR2138160A1 (en) Ferromagnetic chromium dioxide prepn by two stages - heating chromium trioxide with tellurium cpd
GB944864A (en) Magnetic recording media

Legal Events

Date Code Title Description
PS Patent sealed
PLNP Patent lapsed through nonpayment of renewal fees