DE2749010C2 - Nadelförmige Teilchen, diese Teilchen enthaltende magnetische Aufzeichnungsträger sowie Verfahren zur Herstellung der Teilchen - Google Patents
Nadelförmige Teilchen, diese Teilchen enthaltende magnetische Aufzeichnungsträger sowie Verfahren zur Herstellung der TeilchenInfo
- Publication number
- DE2749010C2 DE2749010C2 DE2749010A DE2749010A DE2749010C2 DE 2749010 C2 DE2749010 C2 DE 2749010C2 DE 2749010 A DE2749010 A DE 2749010A DE 2749010 A DE2749010 A DE 2749010A DE 2749010 C2 DE2749010 C2 DE 2749010C2
- Authority
- DE
- Germany
- Prior art keywords
- particles
- cobalt
- acicular
- magnetic recording
- recording media
- 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
Links
- 239000002245 particle Substances 0.000 title claims description 57
- 230000005291 magnetic effect Effects 0.000 title claims description 14
- 238000000034 method Methods 0.000 title claims description 13
- 239000010941 cobalt Substances 0.000 claims description 14
- 229910017052 cobalt Inorganic materials 0.000 claims description 14
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 14
- 239000002344 surface layer Substances 0.000 claims description 8
- 239000012298 atmosphere Substances 0.000 claims description 5
- 239000003638 chemical reducing agent Substances 0.000 claims description 5
- 239000011248 coating agent Substances 0.000 claims description 5
- 238000000576 coating method Methods 0.000 claims description 5
- 150000001869 cobalt compounds Chemical class 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 229910002588 FeOOH Inorganic materials 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- 229910052799 carbon Inorganic materials 0.000 claims description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 7
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 6
- 229910001429 cobalt ion Inorganic materials 0.000 description 6
- XLJKHNWPARRRJB-UHFFFAOYSA-N cobalt(2+) Chemical compound [Co+2] XLJKHNWPARRRJB-UHFFFAOYSA-N 0.000 description 6
- 239000011162 core material Substances 0.000 description 6
- 239000002002 slurry Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 125000005456 glyceride group Chemical group 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 230000005415 magnetization Effects 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 238000010926 purge Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- 150000001868 cobalt Chemical class 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 230000002427 irreversible effect Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 238000004448 titration Methods 0.000 description 2
- UPMLOUAZCHDJJD-UHFFFAOYSA-N 4,4'-Diphenylmethane Diisocyanate Chemical compound C1=CC(N=C=O)=CC=C1CC1=CC=C(N=C=O)C=C1 UPMLOUAZCHDJJD-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 159000000021 acetate salts Chemical class 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 150000001412 amines Chemical group 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- DHAZIUXMHRHVMP-UHFFFAOYSA-N butyl tetradecanoate Chemical compound CCCCCCCCCCCCCC(=O)OCCCC DHAZIUXMHRHVMP-UHFFFAOYSA-N 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 229910000428 cobalt oxide Inorganic materials 0.000 description 1
- IVMYJDGYRUAWML-UHFFFAOYSA-N cobalt(ii) oxide Chemical compound [Co]=O IVMYJDGYRUAWML-UHFFFAOYSA-N 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 238000013213 extrapolation Methods 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000008240 homogeneous mixture Substances 0.000 description 1
- 238000000265 homogenisation Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000012452 mother liquor Substances 0.000 description 1
- SLCVBVWXLSEKPL-UHFFFAOYSA-N neopentyl glycol Chemical compound OCC(C)(C)CO SLCVBVWXLSEKPL-UHFFFAOYSA-N 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- -1 polyethylene terephthalate Polymers 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920001451 polypropylene glycol Polymers 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- UFTFJSFQGQCHQW-UHFFFAOYSA-N triformin Chemical compound O=COCC(OC=O)COC=O UFTFJSFQGQCHQW-UHFFFAOYSA-N 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 229910006540 α-FeOOH Inorganic materials 0.000 description 1
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
- G11B5/70642—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 iron oxides
- G11B5/70678—Ferrites
- G11B5/70684—Ferro-ferrioxydes
- G11B5/70694—Non-stoechiometric ferro-ferrioxydes, e.g. berthollide
-
- 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
- G11B5/70642—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 iron oxides
- G11B5/70678—Ferrites
- G11B5/70684—Ferro-ferrioxydes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S428/00—Stock material or miscellaneous articles
- Y10S428/90—Magnetic feature
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
- Y10T428/2991—Coated
Landscapes
- Hard Magnetic Materials (AREA)
- Magnetic Record Carriers (AREA)
- Paints Or Removers (AREA)
- Compounds Of Iron (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US05/736,744 US4137342A (en) | 1976-10-29 | 1976-10-29 | Cobalt-doped acicular hyper-magnetite particles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| DE2749010A1 DE2749010A1 (de) | 1978-05-11 |
| DE2749010C2 true DE2749010C2 (de) | 1983-01-20 |
Family
ID=24961134
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE2749010A Expired DE2749010C2 (de) | 1976-10-29 | 1977-10-28 | Nadelförmige Teilchen, diese Teilchen enthaltende magnetische Aufzeichnungsträger sowie Verfahren zur Herstellung der Teilchen |
Country Status (15)
| Country | Link |
|---|---|
| US (1) | US4137342A (Direct) |
| JP (1) | JPS5852927B2 (Direct) |
| AR (1) | AR214343A1 (Direct) |
| AT (1) | AT365356B (Direct) |
| AU (1) | AU514316B2 (Direct) |
| BE (1) | BE860291A (Direct) |
| BR (1) | BR7707242A (Direct) |
| CA (1) | CA1097057A (Direct) |
| DE (1) | DE2749010C2 (Direct) |
| FR (1) | FR2369214A1 (Direct) |
| GB (1) | GB1594727A (Direct) |
| IT (1) | IT1090198B (Direct) |
| NL (1) | NL188483C (Direct) |
| SU (1) | SU921474A3 (Direct) |
| ZA (1) | ZA775470B (Direct) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4364988A (en) * | 1978-07-31 | 1982-12-21 | Hitachi Maxell, Ltd. | Magnetic recording medium |
| JPS55149137A (en) * | 1979-05-11 | 1980-11-20 | Tdk Corp | High performance high coercive force powder and its manufacture |
| JPS5626729A (en) * | 1979-08-11 | 1981-03-14 | Tdk Corp | Powdered magnetic material for magnetic recording medium |
| US4388367A (en) * | 1981-09-28 | 1983-06-14 | Xerox Corporation | Perpendicular magnetic recording medium and fabrication |
| DE3277337D1 (en) * | 1981-09-28 | 1987-10-22 | Xerox Corp | Post treatment of perpendicular magnetic recording media |
| US4501774A (en) * | 1981-10-12 | 1985-02-26 | Ishihara Sangyo Kaisha, Ltd. | Process for the production of cobalt-containing magnetic iron oxide powder |
| DE3143870A1 (de) * | 1981-11-05 | 1983-05-11 | Basf Ag, 6700 Ludwigshafen | Verfahren zur herstellung von nadelfoermigen, ferrimagnetischen eisenoxiden |
| DE3224325A1 (de) * | 1982-06-30 | 1984-01-05 | Basf Ag, 6700 Ludwigshafen | Verfahren zur herstellung von nadelfoermigen, ferrimagnetischen eisenoxiden |
| US4842759A (en) * | 1983-04-25 | 1989-06-27 | Daikin Industries, Ltd. | Acicular process for producing particulate material |
| US5151206A (en) * | 1983-04-25 | 1992-09-29 | Daikin Industries, Ltd. | Acicular iron carbide particulate material and process for producing same |
| JPS60143431A (ja) * | 1983-12-29 | 1985-07-29 | Alps Electric Co Ltd | 垂直磁気記録媒体 |
| US5069216A (en) * | 1986-07-03 | 1991-12-03 | Advanced Magnetics Inc. | Silanized biodegradable super paramagnetic metal oxides as contrast agents for imaging the gastrointestinal tract |
| US5219554A (en) * | 1986-07-03 | 1993-06-15 | Advanced Magnetics, Inc. | Hydrated biodegradable superparamagnetic metal oxides |
| US5106437A (en) * | 1987-11-25 | 1992-04-21 | Minnesota Mining And Manufacturing Company | Electromagnetic radiation suppression cover |
| US4814546A (en) * | 1987-11-25 | 1989-03-21 | Minnesota Mining And Manufacturing Company | Electromagnetic radiation suppression cover |
| US5932330A (en) * | 1993-09-30 | 1999-08-03 | Imation Corp. | Coated magnetic recording medium, paint for coated magnetic medium and method for producing coated magnetic medium |
| WO1996013461A1 (en) * | 1994-10-31 | 1996-05-09 | Minnesota Mining And Manufacturing Company | Method of producing magnetic iron oxide |
| US6030695A (en) * | 1996-03-28 | 2000-02-29 | Imation Corp. | Coated magnetic recording medium, paint for coated magnetic medium and method for producing coated magnetic medium |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3770500A (en) | 1969-09-16 | 1973-11-06 | Tdk Electronics Co Ltd | Magnetic materials and method of making same |
| JPS5029157B1 (Direct) * | 1971-05-27 | 1975-09-20 | ||
| JPS5225959B2 (Direct) * | 1972-01-13 | 1977-07-11 | ||
| US3977985A (en) * | 1972-02-23 | 1976-08-31 | Tdk Electronics Company, Limited | Magnetic recording medium comprising cobalt or cobalt alloy coated particles of spicular magnetite |
| US3932293A (en) * | 1972-05-22 | 1976-01-13 | Minnesota Mining And Manufacturing Company | Metallic ferromagnetic particles for use in environmentally stable magnetic recording media |
| US4064292A (en) * | 1972-09-01 | 1977-12-20 | Badische Anilin- & Soda-Fabrik, Aktiengesellschaft | Manufacture of cobalt-modified γ-iron(III)oxides |
| JPS5321118B2 (Direct) * | 1973-03-05 | 1978-06-30 | ||
| US4010310A (en) * | 1973-03-20 | 1977-03-01 | Tdk Electronics Company, Limited | Magnetic powder |
| JPS5242363B2 (Direct) * | 1973-03-20 | 1977-10-24 | ||
| JPS5133758A (Direct) * | 1974-09-17 | 1976-03-23 | Fuji Photo Film Co Ltd | |
| JPS608606B2 (ja) * | 1975-07-02 | 1985-03-04 | 富士写真フイルム株式会社 | 強磁性粉末の製法 |
| JPS5853493B2 (ja) * | 1975-07-02 | 1983-11-29 | 富士写真フイルム株式会社 | キヨウジセイフンマツノセイホウ |
-
1976
- 1976-10-29 US US05/736,744 patent/US4137342A/en not_active Expired - Lifetime
-
1977
- 1977-09-12 ZA ZA00775470A patent/ZA775470B/xx unknown
- 1977-09-21 CA CA287,156A patent/CA1097057A/en not_active Expired
- 1977-10-14 AU AU29691/77A patent/AU514316B2/en not_active Expired
- 1977-10-26 NL NLAANVRAGE7711724,A patent/NL188483C/xx not_active IP Right Cessation
- 1977-10-27 BR BR7707242A patent/BR7707242A/pt unknown
- 1977-10-28 AT AT0771777A patent/AT365356B/de not_active IP Right Cessation
- 1977-10-28 FR FR7732581A patent/FR2369214A1/fr active Granted
- 1977-10-28 BE BE182202A patent/BE860291A/xx not_active IP Right Cessation
- 1977-10-28 IT IT51633/77A patent/IT1090198B/it active
- 1977-10-28 DE DE2749010A patent/DE2749010C2/de not_active Expired
- 1977-10-28 GB GB45042/77A patent/GB1594727A/en not_active Expired
- 1977-10-28 AR AR269764A patent/AR214343A1/es active
- 1977-10-28 SU SU772537598A patent/SU921474A3/ru active
- 1977-10-28 JP JP52129579A patent/JPS5852927B2/ja not_active Expired
Non-Patent Citations (1)
| Title |
|---|
| NICHTS-ERMITTELT |
Also Published As
| Publication number | Publication date |
|---|---|
| IT1090198B (it) | 1985-06-18 |
| BE860291A (fr) | 1978-04-28 |
| SU921474A3 (ru) | 1982-04-15 |
| US4137342A (en) | 1979-01-30 |
| BR7707242A (pt) | 1978-08-08 |
| AU2969177A (en) | 1979-04-26 |
| NL188483C (nl) | 1992-07-01 |
| AR214343A1 (es) | 1979-05-31 |
| DE2749010A1 (de) | 1978-05-11 |
| JPS5852927B2 (ja) | 1983-11-26 |
| NL7711724A (nl) | 1978-05-03 |
| NL188483B (nl) | 1992-02-03 |
| FR2369214A1 (fr) | 1978-05-26 |
| JPS5360399A (en) | 1978-05-30 |
| FR2369214B1 (Direct) | 1984-06-29 |
| AT365356B (de) | 1982-01-11 |
| CA1097057A (en) | 1981-03-10 |
| ZA775470B (en) | 1978-07-26 |
| ATA771777A (de) | 1981-05-15 |
| AU514316B2 (en) | 1981-02-05 |
| GB1594727A (en) | 1981-08-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| OD | Request for examination | ||
| D2 | Grant after examination | ||
| 8364 | No opposition during term of opposition |