JPH0312324A - Production of iron oxide magnetic powder - Google Patents
Production of iron oxide magnetic powderInfo
- Publication number
- JPH0312324A JPH0312324A JP14893889A JP14893889A JPH0312324A JP H0312324 A JPH0312324 A JP H0312324A JP 14893889 A JP14893889 A JP 14893889A JP 14893889 A JP14893889 A JP 14893889A JP H0312324 A JPH0312324 A JP H0312324A
- Authority
- JP
- Japan
- Prior art keywords
- powder
- magnetic powder
- colloidal silica
- silicon oxide
- magnetic
- 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.)
- Granted
Links
- 239000006247 magnetic powder Substances 0.000 title claims abstract description 23
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 title claims abstract description 14
- 238000004519 manufacturing process Methods 0.000 title claims description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 34
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 25
- 239000008119 colloidal silica Substances 0.000 claims abstract description 15
- 239000000843 powder Substances 0.000 claims abstract description 15
- 229910052814 silicon oxide Inorganic materials 0.000 claims abstract description 15
- 239000000725 suspension Substances 0.000 claims abstract description 5
- 239000002245 particle Substances 0.000 claims description 11
- 238000000034 method Methods 0.000 abstract description 19
- 238000004381 surface treatment Methods 0.000 abstract description 14
- 239000011248 coating agent Substances 0.000 abstract description 6
- 238000000576 coating method Methods 0.000 abstract description 6
- 230000008859 change Effects 0.000 abstract description 4
- 229910006297 γ-Fe2O3 Inorganic materials 0.000 abstract description 4
- 230000008569 process Effects 0.000 abstract description 2
- 238000004140 cleaning Methods 0.000 abstract 1
- 239000008199 coating composition Substances 0.000 abstract 1
- 239000002002 slurry Substances 0.000 description 18
- 238000005406 washing Methods 0.000 description 16
- 229910001566 austenite Inorganic materials 0.000 description 8
- TWJNQYPJQDRXPH-UHFFFAOYSA-N 2-cyanobenzohydrazide Chemical compound NNC(=O)C1=CC=CC=C1C#N TWJNQYPJQDRXPH-UHFFFAOYSA-N 0.000 description 7
- TUNFSRHWOTWDNC-UHFFFAOYSA-N Myristic acid Natural products CCCCCCCCCCCCCC(O)=O TUNFSRHWOTWDNC-UHFFFAOYSA-N 0.000 description 7
- 235000021360 Myristic acid Nutrition 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 7
- 238000001914 filtration Methods 0.000 description 7
- 238000001179 sorption measurement Methods 0.000 description 7
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 239000007788 liquid Substances 0.000 description 5
- 238000006386 neutralization reaction Methods 0.000 description 5
- 239000003973 paint Substances 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- 230000006872 improvement Effects 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 239000004115 Sodium Silicate Substances 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- 235000019795 sodium metasilicate Nutrition 0.000 description 3
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 3
- 229910052911 sodium silicate Inorganic materials 0.000 description 3
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 238000012856 packing Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- POWFTOSLLWLEBN-UHFFFAOYSA-N tetrasodium;silicate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-][Si]([O-])([O-])[O-] POWFTOSLLWLEBN-UHFFFAOYSA-N 0.000 description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 2
- IIZPXYDJLKNOIY-JXPKJXOSSA-N 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine Chemical compound CCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCC[N+](C)(C)C)OC(=O)CCC\C=C/C\C=C/C\C=C/C\C=C/CCCCC IIZPXYDJLKNOIY-JXPKJXOSSA-N 0.000 description 1
- MQIUGAXCHLFZKX-UHFFFAOYSA-N Di-n-octyl phthalate Natural products CCCCCCCCOC(=O)C1=CC=CC=C1C(=O)OCCCCCCCC MQIUGAXCHLFZKX-UHFFFAOYSA-N 0.000 description 1
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 1
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 1
- 229920002433 Vinyl chloride-vinyl acetate copolymer Polymers 0.000 description 1
- 229920000180 alkyd Polymers 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
- 238000013459 approach Methods 0.000 description 1
- BJQHLKABXJIVAM-UHFFFAOYSA-N bis(2-ethylhexyl) phthalate Chemical compound CCCCC(CC)COC(=O)C1=CC=CC=C1C(=O)OCC(CC)CCCC BJQHLKABXJIVAM-UHFFFAOYSA-N 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000001023 inorganic pigment Substances 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 239000000787 lecithin Substances 0.000 description 1
- 229940067606 lecithin Drugs 0.000 description 1
- 235000010445 lecithin Nutrition 0.000 description 1
- 239000006249 magnetic particle Substances 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 229920006267 polyester film Polymers 0.000 description 1
- 238000011085 pressure filtration Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 150000003377 silicon compounds Chemical class 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 239000006228 supernatant Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、酸化鉄磁性粉末の製造方法に関し、特に保磁
力の経時変化が少なく塗料分散性の優れた酸化鉄磁性粉
末の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing iron oxide magnetic powder, and particularly to a method for producing iron oxide magnetic powder that exhibits little change in coercive force over time and excellent paint dispersibility.
従来、無機顔料の酸化チタン等では分散性を向上させる
ための表面処理方法が研究されている。Conventionally, research has been conducted on surface treatment methods for improving the dispersibility of inorganic pigments such as titanium oxide.
例えば、酸化チタン表面を５ｉ０２・ｎＨ，０で処理し
、リルン酸含有アルキッド樹脂の吸着量が減少すること
を見出している〔Ｋ、 Ｇｃｌｄｓｂｒｏｕｇｈ。For example, it has been found that when the surface of titanium oxide is treated with 5i02.nH,0, the adsorption amount of alkyd resin containing lylic acid is reduced [K, Gcldsbrough.
Ｊ、Ｐｅａｃｏｃｋ、Ｊ ｏｉｌ ＆ Ｃｏ１ｏｕｒ
ｃｈｅｍ、Ａｓ！！ｏｃ、 ５４，５０６（１９７１）
）。J, Peacock, J oil & Co1our
Chem, As! ! oc, 54, 506 (1971)
).
上記樹脂の吸着量の減少は粉体表面における酸点、塩基
点、酸化点、還元点の各活性点の減少で説明することが
出来る。The decrease in the adsorption amount of the resin can be explained by the decrease in the number of active sites such as acid sites, base sites, oxidation sites, and reduction sites on the powder surface.
これら顔料の表面処理による分散性改良技術（尾、近時
磁気記録媒体の分散性改良にも応用され、種々な表面処
理方法が提案されている。Techniques for improving the dispersibility of these pigments by surface treatment (recently, this technique has also been applied to improving the dispersibility of magnetic recording media, and various surface treatment methods have been proposed).
特にビデオテープでは、ノイズを低減するため、磁性粉
末は微粒化される方向にある。この場合、粒子の表面積
が増加し、塗料分散性に与える粒子の特性の影響が表面
活性点の増加によって大きくなるが、これに対する適切
な処理方法が特に望まれるようになった。Particularly in video tapes, magnetic powders are becoming more atomized in order to reduce noise. In this case, the surface area of the particles increases, and the influence of particle characteristics on paint dispersibility becomes greater due to the increase in surface active sites, and an appropriate treatment method for this is particularly desired.
磁性粉末の処理方法としては、アルミナ、或いはシリカ
による表面処理が公知である。例えば、γ−Ｆ ｅ、Ｏ
、系磁性粉末をオルトケイ酸ナトリウム、メタケイ酸ナ
トリウム等のケイ素化合物の水溶液に分散させた後、中
和、水洗、濾過、乾燥させで粒子表面に均一な酸化ケイ
素被膜を形成する方法（特開昭６ ＋、 −６３９２１
号公報）が発表されている。As a method for treating magnetic powder, surface treatment with alumina or silica is known. For example, γ-F e, O
, a method in which a uniform silicon oxide film is formed on the particle surface by dispersing magnetic powder in an aqueous solution of a silicon compound such as sodium orthosilicate or sodium metasilicate, followed by neutralization, washing with water, filtration, and drying. 6 +, -63921
Publication No.) has been announced.
しかしながら、上記方法は、表面処理のために、γ−Ｆ
ｅ２Ｏ３系磁性粉末を水溶液中に分散し、オルトケイ酸
ナトリウム、或いはメタケイ酸ナトリウム等を添加した
後、中和、濾過、水洗を行なう必要がある。中和処理を
しないと、強固な酸化ケイ素彼膜が形成されず、その後
の水洗において被膜が離脱し、分散性の改良が損なわれ
る。しかし中和処理をすると、得られた磁性粉末の磁性
保持力（以下Ｈｃといううを損なうという問題を生ずる
。However, the above method requires γ-F for surface treatment.
After dispersing the e2O3 magnetic powder in an aqueous solution and adding sodium orthosilicate, sodium metasilicate, etc., it is necessary to perform neutralization, filtration, and washing with water. If neutralization treatment is not performed, a strong silicon oxide film will not be formed, and the film will come off during subsequent washing with water, impairing the improvement in dispersibility. However, the neutralization treatment causes a problem in that the magnetic coercivity (hereinafter referred to as Hc) of the obtained magnetic powder is impaired.
本発明は、上記の問題を解決すべくなされたもので、表
面処理によるＨａの低下が少なく、塗料化する際の分散
性をよくするとともに、磁気テープのＨｃの経時変化を
少なくする酸化ケイ素被覆による酸化鉄磁性粉末の製造
方法を提供することを目的とする。The present invention was made in order to solve the above problems, and has a silicon oxide coating that reduces the decrease in Ha due to surface treatment, improves the dispersibility when forming into a paint, and reduces the change in Hc of a magnetic tape over time. An object of the present invention is to provide a method for producing iron oxide magnetic powder.
上記の目的を達成するため、本発明の方法においては、
γ−ＦｅｔＯｉ系磁性粉末が水に分散したｐＨが９〜１
１．０の懸濁液に、コロイダルシリカを添加し、洗浄、
脱水して前記粉末粒子の表面に酸化ケイ素をＳｉとして
１０００〜１１００００ｐｐ被着させる。 本発明に用
いられるγ−Ｆ ｅ、Ｏ、系磁性粉末としては、特性の
優れたＣｏ−γ−Ｆ ｅ、Ｏｓ、Ｆｅ−ｃｏ−７−Ｆｅ
ｙＯ３が代表的なものである。Ｃ。In order to achieve the above object, in the method of the present invention,
The pH of the γ-FetOi magnetic powder dispersed in water is 9 to 1.
Colloidal silica was added to the suspension of 1.0, washed,
After dehydration, 1,000 to 110,000 pp of silicon oxide as Si is deposited on the surface of the powder particles. The γ-Fe, O, and magnetic powder used in the present invention includes Co-γ-Fe, Os, and Fe-co-7-Fe, which have excellent properties.
yO3 is a typical example. C.
７ ＦｅｔＣ）ｓ、Ｆｅ−Ｃｏ−７−Ｆｅｚ○３の粉
末はγ−Ｆｅ！０３粉末をＮａＯＨ水溶液に添加した後
、昇温し、Ｃｏ塩、或いはＣｏ塩、次いでＦｅ塩を添加
反応させる公知の方法によってつくられる。以下ＣＯ−
γ−Ｆｅｖ○、を代表例として説明する。7 FetC)s, Fe-Co-7-Fez○3 powder is γ-Fe! It is produced by a known method of adding 03 powder to an aqueous NaOH solution, raising the temperature, and adding and reacting Co salt, or Co salt, and then Fe salt. Below CO-
γ-Fev○ will be explained as a representative example.
生成したＣｏ−γ−Ｆｅ、○、は水洗されるが、水洗は
密閉型自動連続加圧濾過装置、或いは、これに類似した
装置によって行なう。この水洗の際にコロイダルシリカ
をスラリータンクに添加し、ＣＯ−γ−Ｆ ｅｇｏ ３
粒子上に均一に強固な酸化ケイ素を破着させる。上記コ
ロイダルシリカの添加時期は、水洗中、Ｐ’ｔ＆のｐＨ
が１１以下になった時点であり、下限には特に制限ない
が、特にＰ夜のｐＨが、コロイダルシリカ溶液のｐ）１
９．５〜１００に近くなった時点で添加するが好ましい
。ｐｌ（が１１を越えるとコロイダルシリカが溶解し、
酸化ケイ素被膜が磁性粒子上に形成されない。また、上
記コロイダルシリカの粒径は、ｃｏ−γ−Ｆｅ。The produced Co-γ-Fe, O, is washed with water, and the water washing is performed using a closed type automatic continuous pressure filtration device or a similar device. During this water washing, colloidal silica was added to the slurry tank, and CO-γ-F ego 3
Breaks strong silicon oxide uniformly onto particles. The timing of adding the above colloidal silica is during water washing, when the pH of P't &
This is the point when the pH of the colloidal silica solution becomes 11 or less, and there is no particular restriction on the lower limit.
It is preferable to add it when it approaches 9.5 to 100. When pl ( exceeds 11, colloidal silica dissolves,
No silicon oxide coating is formed on the magnetic particles. Further, the particle size of the colloidal silica is co-γ-Fe.
０３粒子表面に均一に破着してこれを被覆するため細い
ものがよく、５〜ｌｏｎｍの粒径のものが好ましい。In order to uniformly adhere to and coat the surface of the 03 particles, it is best to use a thin one, and preferably one with a particle size of 5 to lonm.
上記コロイダルシリカの付着ｍは、Ｓｉ換算で１０００
〜１１００００ｐｐであり、特に１５００〜５０００ｐ
ｐｍが好ましい。上記付着量が１１０００ｐｐ未満では
分散性改良効果が不充分であり、１１００００ｐｐを越
えても分散性の改良は進まず、かえって磁気特性の低下
をまね（。この理由は定かでないが、１１００００ｐｐ
を越えるとＣｏ−γ−Ｆ ｅ、ｏ 、磁性粉の塩基点の
減少が飽和に達するためと思料する。The adhesion m of the colloidal silica is 1000 in terms of Si.
~110000pp, especially 1500~5000p
pm is preferred. If the amount of adhesion is less than 11,000 pp, the effect of improving dispersibility is insufficient, and even if it exceeds 110,000 pp, the improvement of dispersibility does not progress, and on the contrary, the magnetic properties deteriorate (The reason for this is not clear, but at 110,000 pp
It is thought that this is because when the value exceeds Co-γ-Fe,o, the decrease in the base sites of the magnetic powder reaches saturation.
上記水洗を行なう装置の一例を第１図（ａ） （ｂ）に
示す。第１図（ａ）は水洗装置の全体図、第１図（ｂ）
は濾過板の縦断面図である。An example of the apparatus for carrying out the above water washing is shown in FIGS. 1(a) and 1(b). Figure 1 (a) is an overall view of the water washing equipment, Figure 1 (b)
is a longitudinal cross-sectional view of a filter plate.
バッフル１ａを有するスラリータンク１にＣｏ−γ−Ｆ
ｅ、Ｏ、スラリーを充填口、所定量のコロイダルシリ
カを添加して撹拌機１ｂで撹拌する。このスラリーをポ
ンプ２で濾過板３に圧送し、濾過板３により水の一部を
層液４として除去し、濃縮スラリー５はスラリータンク
１に循環されるとともに、上記濾過板３の層液４と同量
の温水６がスラリータンクに供給される。これを繰返え
し層液のｐＨが８．０となった時点で水洗は終了する。Co-γ-F in slurry tank 1 having baffle 1a
e. O. Fill the slurry with a filling port, add a predetermined amount of colloidal silica, and stir with the stirrer 1b. This slurry is pumped to the filter plate 3 by the pump 2, a part of the water is removed by the filter plate 3 as a layer liquid 4, the concentrated slurry 5 is circulated to the slurry tank 1, and the layer liquid 4 of the filter plate 3 is removed. The same amount of hot water 6 is supplied to the slurry tank. This process is repeated until the pH of the layer solution reaches 8.0, at which point the water washing is completed.
なお、コロイダルシリカはＣｏ−γ−ＦｅｔＯ３に付着
しているので、層重３ａを通すことはなく、またスラリ
ーが循環しているのでＣＯ−γ−Ｆｅ。Note that colloidal silica is attached to Co-γ-FetO3, so it does not pass through the layer 3a, and since the slurry is circulating, it is CO-γ-Fe.
０３粒子が層重３ａに沈着することがない。また図中Ｐ
Ｇは圧力形、７は電磁流量計、８は積算流量計、９はバ
ルブ、１０はジヨイント、１１は戸枠、１２はスラリー
流路、１３は排水流路である。03 particles are not deposited on the layer 3a. Also, P in the figure
G is a pressure type, 7 is an electromagnetic flowmeter, 8 is an integrated flowmeter, 9 is a valve, 10 is a joint, 11 is a door frame, 12 is a slurry flow path, and 13 is a drainage flow path.
このようにしてＣＯ−γ−Ｆ ｅｇｏ ３磁性粉末の表
面を酸化ケイ素被膜で被覆する方法は、ＣＯ−γ−Ｆ
ｅｔｏ ３スラリーの水洗濾過工程中で実施出来、表面
処理後、酸による中和処理が必要ないため、ＣＯ−γ−
Ｆｅ２Ｏ３のＨｃ低下が少ない。The method of coating the surface of CO-γ-F ego 3 magnetic powder with a silicon oxide film in this way is
It can be carried out during the water washing and filtration process of eto 3 slurry, and there is no need for neutralization treatment with acid after surface treatment, so CO-γ-
Fe2O3 Hc decrease is small.
次に実施例、比較例を示して本発明を説明する。 Next, the present invention will be explained by showing examples and comparative examples.
実施例１
従来公知の方法によりγ−Ｆ ｅ２Ｏ３にＣｏおよびＦ
ｅの被着処理を施したＦｅ−Ｃｏ−７−ＦＪＯ３スラリ
ー２００１２を第１図（ａ）の水洗装置のスラリータン
クに入れ、ポンプによりスラリーを濾過板に圧送し濾過
水洗を行なった。濾過水洗中に排出された層液のｐＨを
測定し、ｐＨが９．５〜１０．０になった時点でコロイ
ダル／す力（触媒化学株式会社製、カタロイドＳ １１
−５００）４５７をスラリータンクに添加し、引続き、
水洗を継続し、Ｐ液のｐＨが８．０になった時点で濾過
水洗を終了した。Example 1 Co and F were added to γ-F e2O3 by a conventionally known method.
The Fe-Co-7-FJO3 slurry 20012 subjected to the adhesion treatment described in e.g. was placed in the slurry tank of the water washing apparatus shown in FIG. The pH of the layer liquid discharged during filtration and washing with water was measured, and when the pH reached 9.5 to 10.0, Colloidal/Suroku (manufactured by Catalyst Kagaku Co., Ltd., Cataloid S 11) was added.
-500) 457 to the slurry tank, followed by
The water washing was continued, and when the pH of the P solution reached 8.0, the filtration and water washing was completed.
水洗が終了した上記スラリーをフィルタプレスで濾過し
た後、濾過ケーキを乾燥器により、６０°Ｃの温度で一
昼夜乾燥して、Ｆｅ−Ｃｏ−γ−ＦｅｔＯ５粒子の表面
が酸化ケイ素で被覆された磁性粉末を得た。After the water-washed slurry was filtered using a filter press, the filtered cake was dried in a dryer at a temperature of 60°C for a day and night, and the surface of the Fe-Co-γ-FetO5 particles was coated with silicon oxide. A powder was obtained.
得られた磁性粉の表面積は３２ｍ２／ｇ、Ｃｏの量は２
ｗｔ％、Ｆｅ”＋は３ 、５ ｗｔ％でＨｃは６１３０
ｅ。The surface area of the obtained magnetic powder was 32 m2/g, and the amount of Co was 2
wt%, Fe”+ is 3.5 wt%, Hc is 6130
e.
Ｓ１付着量はｔｇｏｏｐｐｍであった。The S1 adhesion amount was tgooppm.
上記酸化ケイ素破着Ｆｅ−Ｃｏ−γ−Ｆｅ２Ｏ３５０ｇ
を用いてミリスチン酸吸着量を測定した。測定方法は、
メチルエチルケトン（ＭＥＫ）１００ｇにミリスチン酸
２ｇを加えた後、上記磁性粉５０ｇを添加し、３０分間
撹拌して静置した。次いで上澄液を濾過し、Ｐ液２５ｇ
を湯浴により蒸発乾固させ、これを乾燥器を用いて１０
０°Ｃで１時間乾燥し、デシケータ内で冷却した後、計
量した。350g of the above silicon oxide broken Fe-Co-γ-Fe2O
The adsorption amount of myristic acid was measured using The measurement method is
After adding 2 g of myristic acid to 100 g of methyl ethyl ketone (MEK), 50 g of the above magnetic powder was added, and the mixture was stirred for 30 minutes and allowed to stand still. Next, the supernatant liquid was filtered, and 25 g of P solution was obtained.
was evaporated to dryness in a hot water bath, and dried in a dryer for 10
After drying at 0°C for 1 hour and cooling in a desiccator, it was weighed.
また、
作製した酸化ケイ素被覆Ｆｅ−Ｃｏ−γ−Ｆ ｅ２Ｏ３
７５重量部
塩化ビニル−酢酸ビニル共重合体 １９ ／／ ／
／ジオクチルフタレート ４ “ “レ
シチン ２ 〃 〃トルエ
ン ｔｏｏ ” 〃メチル
イソブチルケトン １０（）〃〃の配合物を
サンドミル中で、１時間混合分散させ、磁性塗料を調製
し、ポリエステルフィルム上に１０μｍの厚さに塗布し
て磁気テープを作製した。In addition, the prepared silicon oxide coated Fe-Co-γ-Fe2O3
75 parts by weight Vinyl chloride-vinyl acetate copolymer 19 // /
/ Dioctyl phthalate 4 "" Lecithin 2 " Toluene too " Methyl isobutyl ketone 10 ( ) " Mixed and dispersed in a sand mill for 1 hour to prepare a magnetic paint and apply it on a polyester film with a thickness of 10 μm A magnetic tape was prepared by coating the
実施例２
コロイダルシリカの添加量を１１４３ｇとした以外は、
実施例１と同じにして表面処理を行ない、ミリスチン酸
吸着量の測定、および磁気テープ作成を行なった。表面
処理によって付着した５ｉｆｆｉは、＋ｓｏｏｐｐｍで
あった。Example 2 Except that the amount of colloidal silica added was 1143 g,
The surface treatment was carried out in the same manner as in Example 1, the amount of myristic acid adsorbed was measured, and a magnetic tape was prepared. 5iffi attached by surface treatment was +sooppm.
比較例１
従来公知の方法によってγＦ ｅ２Ｏ３にＦｅおよびＣ
ｏ彼積着処理たスラリーを表面処理することなく、その
まま濾過水洗してＦｅ−ｃｏ−γ−Ｆ ｅｔ０３磁性粉
末を得た。この磁性粉末を用い、実施例１と同じにして
ミリスチン酸吸着量測定および磁気テープの作製を行な
った。Comparative Example 1 Fe and C were added to γF e2O3 by a conventionally known method.
The slurry subjected to the deposition treatment was filtered and washed with water without surface treatment to obtain Fe-co-γ-Fet03 magnetic powder. Using this magnetic powder, the adsorption amount of myristic acid was measured and a magnetic tape was prepared in the same manner as in Example 1.
比較例２
コロイダルシリカの添加量を３４２９ ｇとした以外は
、実施例１と同じにして表面処理し、ミリスチン酸吸着
量の測定、磁気テープの作製を行なった。Comparative Example 2 The surface treatment was carried out in the same manner as in Example 1 except that the amount of colloidal silica added was 3429 g, and the adsorption amount of myristic acid was measured and a magnetic tape was prepared.
この場合表面処理によって付着した５ｉｆｆｌは、１３
８００ｐｐｍであった。In this case, 5iffl attached by surface treatment is 13
It was 800 ppm.
比較例３
メタケイ酸ソーダ４．０ｇを溶解した水溶液ＩＱに、従
来公知の方法によって得られたＦｅ−Ｃ０γ−Ｆ ｅ、
ｏ ３粉末１００ｇを懸濁させ撹拌しながら酢酸を添加
し、ｐＨ７，５まで中和する。次いで、水洗濾過により
酸化ケイ素で表面被覆されたＦｅ・Ｃｏ−γ−Ｆ ｅ、
ｏ 、粉末を得た。これを第１実施例と同じにして、ミ
リスチン酸吸着量の測定、磁性テープの作製を行なった
。この場合、表面処理によって付着した５ｉｆｆｔは３
９００ｐｐｍであった。Comparative Example 3 Fe-C0γ-Fe obtained by a conventionally known method was added to an aqueous solution IQ in which 4.0 g of sodium metasilicate was dissolved.
Suspend 100 g of o3 powder and add acetic acid while stirring to neutralize to pH 7.5. Then, Fe・Co-γ-Fe whose surface was coated with silicon oxide by washing and filtration with water,
o, powder was obtained. The adsorption amount of myristic acid was measured and a magnetic tape was prepared in the same manner as in the first example. In this case, 5ifft attached by surface treatment is 3
It was 900 ppm.
上記実施例１，２、比較例１，２におけるミリスチン酸
吸着量、磁気テープについて角型比、出力（３％ＴＨＤ
ＭＯＬ） 、Ｓ Ｆ Ｄ （反転磁界強度分布）を測定
し、また実施例１，２、比較例１，２．３における粉体
の磁気特性、Ｈｃ（保持力）、σＳ（飽和磁化）を測定
した。The adsorption amount of myristic acid in Examples 1 and 2 and Comparative Examples 1 and 2, the squareness ratio of the magnetic tape, and the output (3% THD
MOL), S F D (reversal magnetic field strength distribution) were measured, and the magnetic properties, Hc (coercive force), and σS (saturation magnetization) of the powders in Examples 1 and 2 and Comparative Examples 1 and 2.3 were measured. did.
上記それぞれの測定は次のようにして行なった。Each of the above measurements was performed as follows.
角型比
測定装置
振動型磁力計
ＶＳＭ−５３−１５
束英工業株式会社製
１．２ｇ／ｃｃ
０ＫＯｅ
資料充填密度
印加磁場
出力
ａｌり定装置
テープ試験用録音機
日本コロンビア株式会社製
型式 ＤＮ−０３１Ｒ
測定方法 周波数３１５Ｈｚにおいて３％の３次高周
波ひずみを発生する
出力レベル。Squareness ratio measuring device Vibrating magnetometer VSM-53-15 Manufactured by Sokuei Kogyo Co., Ltd. 1.2 g/cc 0 KOe Data packing density applied magnetic field output Al determination device Tape test recorder Manufactured by Nippon Columbia Co., Ltd. Model DN-031R Measurement method: Output level that generates 3% third-order high frequency distortion at a frequency of 315Hz.
ＳＦＤ
磁気テープの磁気履歴曲線の微分曲線を測定しその半値
幅をＨｃで除した値。SFD A value obtained by measuring the differential curve of the magnetic history curve of a magnetic tape and dividing its half width by Hc.
Ｈｃ 角型比に同じ。Hc Same as square ratio.
σ Ｓ 角型比に同じ。σ S Same as square ratio.
結果を第１表に一括してに示した。The results are summarized in Table 1.
また、実施例１．２と比較例１の磁気テープを大気中６
０°Ｃに保持し、２０日、４０日経過後の１−ｉ ｃを
測定した。結果を第２表に示した。In addition, the magnetic tapes of Example 1.2 and Comparative Example 1 were exposed to
It was maintained at 0°C and 1-ic was measured after 20 and 40 days. The results are shown in Table 2.
第 ２ 表
〔発明の効果〕
以上述べたように、本発明の方法は、磁気テープの角型
比を向上せしめ、塗料化時の分散性を改良する。この分
散性の向上によって塗膜中の磁性粉の充填密度が高（な
り、３％ＴＨＤＭＯＬが向上し、また配向性がよ（なる
ことによりＳＦＤも改良され、さらに保持力の経時変化
も少なくなる等多くの長所を有する。Table 2 [Effects of the Invention] As described above, the method of the present invention improves the squareness ratio of the magnetic tape and improves the dispersibility when it is made into a paint. This improvement in dispersibility results in a higher packing density of magnetic powder in the coating film, an improvement in 3% THDMOL, and a better orientation (as a result, SFD is improved, and changes in holding power over time are also reduced). etc. It has many advantages.
第１図（ａ）（ｂ）は本発明の方法に用いられる水洗濾
過装置の一例を示す図で、第１図（ａ）は全体図、第１
図（ｂ）は第１図（ａ）のｒ−１線矢視断面図である。
１・・・スラリータンク、ｌａ・・・・・・バッフル、
ｌｂ・・・・・撹拌機、２・・・・・・ポンプ、３・・
・・・濾過板、３ａ・・層重、４・・・・・Ｐ液、５・
・・・・濃縮スラリー６温水、７・・・・・電磁流ｌ計
、８・・・・・・積算流量計、９・・・・・バルブ、１
０ ・・・・ジヨイント、１１・旧・戸枠、１２・・・
・・スラリー流路、１３・・・・・排水流路。FIGS. 1(a) and 1(b) are diagrams showing an example of a water washing filtration device used in the method of the present invention, and FIG. 1(a) is an overall view;
FIG. 1(b) is a sectional view taken along the line r-1 in FIG. 1(a). 1...Slurry tank, la...baffle,
lb... Stirrer, 2... Pump, 3...
...Filter plate, 3a...Layer weight, 4...P liquid, 5.
... Concentrated slurry 6 Hot water, 7 ... Electromagnetic flow meter, 8 ... Integrating flow meter, 9 ... Valve, 1
0... joint, 11, old door frame, 12...
... Slurry channel, 13... Drainage channel.
Claims (1)
１１．０以下の懸濁液にコロイダルシリカを添加し、洗
浄、脱水して前記粉末粒子の表面に酸化ケイ素をＳｉと
して１０００〜１００００ｐｐｍ被着させることを特徴
とした酸化鉄磁性粉末の製造方法。Colloidal silica is added to a suspension of γ-Fe_2O_3-based magnetic powder dispersed in water with a pH of 11.0 or less, washed and dehydrated, and 1000 to 10000 ppm of silicon oxide as Si is deposited on the surface of the powder particles. A method for producing iron oxide magnetic powder characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14893889A JPH0312324A (en) | 1989-06-12 | 1989-06-12 | Production of iron oxide magnetic powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14893889A JPH0312324A (en) | 1989-06-12 | 1989-06-12 | Production of iron oxide magnetic powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0312324A true JPH0312324A (en) | 1991-01-21 |
| JPH0574534B2 JPH0574534B2 (en) | 1993-10-18 |
Family
ID=15464018
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14893889A Granted JPH0312324A (en) | 1989-06-12 | 1989-06-12 | Production of iron oxide magnetic powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0312324A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6216949B1 (en) * | 2015-10-05 | 2017-10-25 | エム・テクニック株式会社 | Silicon oxide-coated iron oxide composition for coating comprising iron oxide particles coated with silicon oxide |
-
1989
- 1989-06-12 JP JP14893889A patent/JPH0312324A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6216949B1 (en) * | 2015-10-05 | 2017-10-25 | エム・テクニック株式会社 | Silicon oxide-coated iron oxide composition for coating comprising iron oxide particles coated with silicon oxide |
| JP2017218374A (en) * | 2015-10-05 | 2017-12-14 | エム・テクニック株式会社 | Silicon oxide-coated iron oxide composition for coating containing iron oxide particles coated with silicon oxide |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0574534B2 (en) | 1993-10-18 |
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