JPH01239820A - Co-coating magnetic iron oxide powder and magnetic recording medium using same - Google Patents
Co-coating magnetic iron oxide powder and magnetic recording medium using sameInfo
- Publication number
- JPH01239820A JPH01239820A JP63066916A JP6691688A JPH01239820A JP H01239820 A JPH01239820 A JP H01239820A JP 63066916 A JP63066916 A JP 63066916A JP 6691688 A JP6691688 A JP 6691688A JP H01239820 A JPH01239820 A JP H01239820A
- Authority
- JP
- Japan
- Prior art keywords
- iron oxide
- oxide powder
- magnetic
- silicon compound
- magnetic iron
- 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.)
- Pending
Links
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 title claims abstract description 130
- 239000000843 powder Substances 0.000 title claims abstract description 68
- 239000011248 coating agent Substances 0.000 title claims abstract description 32
- 238000000576 coating method Methods 0.000 title claims abstract description 32
- 150000003377 silicon compounds Chemical class 0.000 claims abstract description 31
- 239000002245 particle Substances 0.000 claims abstract description 19
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 18
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229910052814 silicon oxide Inorganic materials 0.000 claims abstract description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 239000010703 silicon Substances 0.000 claims description 4
- XJKVPKYVPCWHFO-UHFFFAOYSA-N silicon;hydrate Chemical compound O.[Si] XJKVPKYVPCWHFO-UHFFFAOYSA-N 0.000 claims 1
- -1 silicon hydrate oxide Chemical compound 0.000 abstract description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 abstract 1
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 9
- 239000010410 layer Substances 0.000 description 8
- 238000010438 heat treatment Methods 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 5
- HEMHJVSKTPXQMS-UHFFFAOYSA-M sodium hydroxide Inorganic materials [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 5
- 150000002500 ions Chemical class 0.000 description 4
- 230000005415 magnetization Effects 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000003973 paint Substances 0.000 description 3
- 229920006267 polyester film Polymers 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 230000002542 deteriorative effect Effects 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 239000012948 isocyanate Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 239000002243 precursor Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- TWJNQYPJQDRXPH-UHFFFAOYSA-N 2-cyanobenzohydrazide Chemical compound NNC(=O)C1=CC=CC=C1C#N TWJNQYPJQDRXPH-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
- TUNFSRHWOTWDNC-UHFFFAOYSA-N Myristic acid Natural products CCCCCCCCCCCCCC(O)=O TUNFSRHWOTWDNC-UHFFFAOYSA-N 0.000 description 1
- 235000021360 Myristic acid Nutrition 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910052770 Uranium Inorganic materials 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 229920002433 Vinyl chloride-vinyl acetate copolymer Polymers 0.000 description 1
- 239000003082 abrasive agent Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000002216 antistatic agent Substances 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000012461 cellulose resin Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 1
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 1
- 239000006247 magnetic powder Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 239000002985 plastic film Substances 0.000 description 1
- 229920006255 plastic film Polymers 0.000 description 1
- 229920002037 poly(vinyl butyral) polymer Polymers 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical class [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
Landscapes
- Paints Or Removers (AREA)
- Magnetic Record Carriers (AREA)
- Hard Magnetic Materials (AREA)
- Compounds Of Iron (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明はＣｏ被着磁性酸化鉄粉末およびこのＣｏ被着
磁性酸化鉄粉末を用いた磁気記録媒体に関し、さらに詳
しくは消去特性に優れたＣｏ被着磁性酸化鉄粉末および
このＣｏ被着磁性酸化鉄粉末を用いて得られる消去特性
に優れた磁気記録媒体に関する。Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a Co-coated magnetic iron oxide powder and a magnetic recording medium using the Co-coated magnetic iron oxide powder, and more specifically to a Co-coated magnetic recording medium using the Co-coated magnetic iron oxide powder. The present invention relates to a magnetized iron oxide powder and a magnetic recording medium with excellent erasing characteristics obtained using the Co magnetized iron oxide powder.
従来から、磁気記録媒体に好適な磁性粉末として、磁性
酸化鉄粉末の粒子表面にＣｏフェライト層をエピタキシ
ャル成長させた、いわゆるＣｏ被着磁性酸化鉄粉末が使
用されている。（特開昭５５−８３２０７号）
〔発明が解決しようとする課題〕
しかしながら、この種のＣｏ被着磁性酸化鉄粉末は、微
粒子になると磁気記録媒体を製造する際の加熱により表
面層のＣｏイオンが内部に拡散しやすくなるため、その
保磁力分布が広くなって、消去特性が悪くなり、このＣ
ｏ被着磁性酸化鉄粉末を使用して得られる磁気記録媒体
の消去特性が悪くなるという問題がある。BACKGROUND ART Conventionally, as a magnetic powder suitable for magnetic recording media, so-called Co-coated magnetic iron oxide powder, in which a Co ferrite layer is epitaxially grown on the particle surface of magnetic iron oxide powder, has been used. (Unexamined Japanese Patent Publication No. 55-83207) [Problems to be Solved by the Invention] However, when this type of Co-coated iron oxide powder becomes fine particles, Co ions in the surface layer are released by heating during manufacturing magnetic recording media. As C becomes more likely to diffuse into the interior, its coercive force distribution widens, deteriorating the erasing characteristics, and this C
o There is a problem in that the erasing characteristics of magnetic recording media obtained using magnetized iron oxide powder deteriorate.
この発明は、かかる欠点を除去するため種々検討を行っ
た結果なされたもので、磁性酸化鉄粉末の粒子表面にケ
イ素化合物からなる被膜を形成し、このケイ素化合物か
らなる被膜上にＣｏフェライトからなる被膜を形成する
ことによって、Ｃ。This invention was made as a result of various studies to eliminate such drawbacks, and involves forming a coating made of a silicon compound on the particle surface of magnetic iron oxide powder, and coating the coating made of Co ferrite on the coating made of the silicon compound. C. by forming a coating.
被着磁性酸化鉄粉末の消去特性を向上させるとともに、
この種のＣｏ被着磁性酸化鉄粉末を用いて得られる磁気
記録媒体の消去特性を向上させたものである。In addition to improving the erasing properties of magnetized iron oxide powder,
The erasing characteristics of a magnetic recording medium obtained using this type of Co-magnetized iron oxide powder are improved.
この発明におけるＣｏ被着磁性酸化鉄粉末は、粒子表面
に予めケイ素化合物からなる被膜を形成し、このケイ素
化合物からなる被膜上にＣｏフェライトからなる被膜を
形成して、磁性酸化鉄粉末の核晶と表面のＣｏフェライ
トとの間に、ケイ素化合物からなる被膜を介在させてい
るため、このケイ素化合物からなる被膜によって加熱に
対する安定性が改善され、磁気記録媒体を製造する際の
加熱では、表面のＣｏフェライト層から核晶の磁性酸化
鉄粉末へのＣｏイオンの拡散が起こらず、Ｃｏ被着磁性
酸化鉄粉末の消去特性が飛躍的に改良されるとともに、
このＣｏ被着磁性酸化鉄粉末を使用して得られる磁気記
録媒体の消去特性が格段と向上される。The Co-adhered magnetic iron oxide powder in the present invention is produced by forming a coating made of a silicon compound on the particle surface in advance, and forming a coating made of Co ferrite on the coating made of the silicon compound to form a core crystal of the magnetic iron oxide powder. Since a coating made of a silicon compound is interposed between the Co ferrite on the surface and the Co ferrite on the surface, stability against heating is improved by this coating made of silicon compound, and during heating when manufacturing magnetic recording media, the surface Co ions do not diffuse from the Co ferrite layer to the magnetic iron oxide powder of the core crystals, and the erasing characteristics of the Co magnetized iron oxide powder are dramatically improved.
The erasing characteristics of a magnetic recording medium obtained by using this Co-coated iron oxide powder are significantly improved.
このような磁性酸化鉄粉末の粒子表面に形成されるケイ
素化合物からなる被膜は、磁性酸化鉄粉末またはその前
駆物質を、ケイ素化合物を含む溶液に浸漬させるか、ま
たはケイ素化合物を含むガスに接触させるなどの方法で
形成され、この際、粒子表面に被着形成したケイ素化合
物被膜を予め熱処理すると、被着が良好に行われるため
熱処理するのが好ましい。この熱処理は、ケイ素化合物
を被着する原料の粉末が磁性酸化鉄粉末の場合、磁気特
性の劣化のない３００ ’Ｃ以下にするのが好ましく、
前駆物質の場合は、形状の崩壊のない９００°Ｃ以下の
温度で熱処理するのが好ましい。A film made of a silicon compound formed on the particle surface of such magnetic iron oxide powder can be formed by immersing the magnetic iron oxide powder or its precursor in a solution containing a silicon compound or bringing it into contact with a gas containing a silicon compound. At this time, it is preferable to heat-treat the silicon compound coating formed on the particle surface because the adhesion will be better if the silicon compound coating is preliminarily heat-treated. When the raw material powder to which the silicon compound is applied is magnetic iron oxide powder, this heat treatment is preferably carried out at a temperature of 300'C or less without deteriorating the magnetic properties.
In the case of a precursor material, it is preferable to heat treat it at a temperature of 900° C. or lower without causing shape collapse.
このようにして磁性酸化鉄粉末の粒子表面に形成される
ケイ素化合物からなる被膜は、ケイ素の酸化物または含
水酸化物として存在すると、Ｃ。When the film made of a silicon compound formed on the particle surface of the magnetic iron oxide powder in this way exists as an oxide or a hydrous oxide of silicon, C.
イオンの拡散防止効果が大きいため、ケイ素の酸化物も
しくは含水酸化物であることが好ましい。Silicon oxides or hydrous oxides are preferable because they have a great effect of preventing ion diffusion.
このようなケイ素化合物からなる被膜中のケイ素は、こ
の後さらにＣｏフェライト層を形成して得られるＣｏ被
着磁性酸化鉄粉末全体に対する重量比で０．００５より
少ないとＣｏイオンの拡散防止効果が小さく、０．０３
より多いとＣｏ被着磁性酸化鉄粉末の飽和磁化が低くな
るため、Ｃｏ被着磁性酸化鉄粉末全体に対する重量比で
０．００５〜０，０３の範囲内となるようにするのが好
ましく、ｏ、ｏｏｓ〜０．０２の範囲内にするのがより
好ましい。If the weight ratio of silicon in the film made of such a silicon compound to the entire Co-coated magnetic iron oxide powder obtained by further forming a Co ferrite layer is less than 0.005, the effect of preventing Co ion diffusion will be low. small, 0.03
If the amount is larger, the saturation magnetization of the Co magnetized iron oxide powder will decrease, so it is preferable that the weight ratio to the whole Co magnetized iron oxide powder is within the range of 0.005 to 0.03. , oos to 0.02.
また、磁性酸化鉄粉末の粒子表面に形成されたケイ素化
合物からなる被膜上に、さらに形成されるＣｏフェライ
ト層は、通常、ＣｏとＦｅの水酸化物を、磁性酸化鉄粉
末の粒子表面に形成されたケイ素化合物からなる被膜の
表面に沈着させ、これを１００°Ｃ以下の温度で熱処理
するなどの方法で形成される。In addition, a Co ferrite layer that is further formed on a coating made of a silicon compound formed on the surface of particles of magnetic iron oxide powder is usually formed by forming hydroxides of Co and Fe on the surface of particles of magnetic iron oxide powder. It is formed by depositing it on the surface of a film made of a silicon compound and heat-treating it at a temperature of 100°C or less.
このようにして゛形成されるＣｏ被着磁性酸化鉄粉末中
のＣｏ含有量は、用途によって異なるが、通常、Ｃｏ被
着磁性酸化鉄粉末全体に対する重量比で０．０１より少
ないと高い保磁力が得られにくく、０．１０より多いと
Ｃｏ被着磁性酸化鉄粉末のコストが高くなるため、Ｃｏ
被着磁性酸化鉄粉末全体に対する重量比で０．０１〜０
．１０の範囲内にするのが好ましい。The Co content in the Co-magnetized iron oxide powder formed in this manner varies depending on the application, but generally, if the weight ratio to the entire Co-magnetized iron oxide powder is less than 0.01, a high coercive force is obtained. Co is difficult to obtain, and if the amount is more than 0.10, the cost of Co magnetized iron oxide powder increases.
0.01 to 0 in weight ratio to the entire magnetized iron oxide powder
．． It is preferable to set it within the range of 10.
このような、ケイ素化合物からなる被膜とＣ。Such a coating made of a silicon compound and C.
フェライト層とを積層形成したＣｏ被着磁性酸化鉄粉末
を用いる磁気記録媒体は、常法に準じて製造され、たと
えば、このＣｏ被着磁性酸化鉄粉末を、結合剤樹脂、有
機溶剤およびその他の必要成分とともに混合分散して磁
性塗料を調製し、これをポリエステルフィルムなどの基
体上に、ロールコータ−など任意の塗布手段によって塗
布し、乾燥して製造される。A magnetic recording medium using a Co-adherable magnetic iron oxide powder laminated with a ferrite layer is manufactured according to a conventional method. A magnetic coating material is prepared by mixing and dispersing the necessary components, and this is coated onto a substrate such as a polyester film using any coating means such as a roll coater, and then dried.
このようにして製造される磁気記録媒体において、Ｃｏ
被着磁性酸化鉄粉末の磁性層中に占める体積は、１５容
量％以上とすると飽和磁束密度が大きくなるため、１５
容量％以上にするのが好ましい。In the magnetic recording medium manufactured in this way, Co
If the volume occupied by the magnetized iron oxide powder in the magnetic layer is 15% by volume or more, the saturation magnetic flux density will increase.
It is preferable to make it % by volume or more.
ここに用いる結合剤樹脂としては、塩化ビニル−酢酸ビ
ニル系共重合体、ポリビニルブチラール樹脂、繊維素系
樹脂、ポリウレタン系樹脂、ポリエステル系樹脂、イソ
シアネート化合物など従来汎用されている結合剤樹脂が
広く用いられる。As the binder resin used here, conventionally widely used binder resins such as vinyl chloride-vinyl acetate copolymer, polyvinyl butyral resin, cellulose resin, polyurethane resin, polyester resin, and isocyanate compound are widely used. It will be done.
また、有機溶剤としては、トルエン、メチルイソブチル
ケトン、メチルエチルケトン、シクロヘキサノン、テト
ラヒドロフラン、酢酸エチルなど従来から汎用されてい
る有機溶剤が、単独または二種以上混合して使用される
。Further, as the organic solvent, conventionally widely used organic solvents such as toluene, methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, and ethyl acetate are used alone or in a mixture of two or more.
なお、磁性塗料中には、通常使用されている各種添加剤
、たとえば、分散剤、研磨剤、帯電防止剤などを任意に
添加使用してもよい。Note that various commonly used additives such as dispersants, abrasives, antistatic agents, etc. may be optionally added to the magnetic paint.
このようにして製造される磁気記録媒体としては、ポリ
エステルフィルムなどのプラスチックフィルムを基体と
し、この基体の片面に磁性層を有する磁気テープ、両面
に磁性層を有する磁気ディスク、さらに円盤やドラムを
基体とする磁気ディスクや磁気ドラムなど、磁気ヘッド
と摺接する種々の形態を包含する。Magnetic recording media manufactured in this way include magnetic tapes that have a plastic film such as polyester film as a base and a magnetic layer on one side of the base, magnetic disks that have magnetic layers on both sides, and disks and drums as bases. It includes various forms that come into sliding contact with a magnetic head, such as magnetic disks and magnetic drums.
次ぎに、この発明の実施例について説明する。 Next, embodiments of the invention will be described.
実施例１〜５
０．５Ｎ−ＮａＯＨ水溶液３００！中に５ｋｇのＴ−Ｆ
ｅｚＯ，粉末（長軸０．２５μｍ、軸比８）を懸濁させ
、これに下記第１表に示す量のＩＭ−ケイ酸ソーダ水溶
液を添加した。次いで、この懸濁液に炭酸ガスを吹き込
み、懸濁液のＰＨが８以下になるまで中和反応させ、粒
子表面にケイ酸ゲルをコーティングした。しかる後、こ
の磁性酸化鉄粉末を洗浄し、２００°Ｃで２時間熱処理
して、磁性酸化鉄粉末の粒子表面にシリカ被膜を形成し
た。Examples 1-5 0.5N-NaOH aqueous solution 300! 5kg of T-F inside
ezO powder (major axis 0.25 μm, axial ratio 8) was suspended, and an aqueous IM-sodium silicate solution in an amount shown in Table 1 below was added thereto. Next, carbon dioxide gas was blown into this suspension to cause a neutralization reaction until the pH of the suspension became 8 or less, and the particle surfaces were coated with silicic acid gel. Thereafter, this magnetic iron oxide powder was washed and heat treated at 200°C for 2 hours to form a silica coating on the particle surface of the magnetic iron oxide powder.
次に、このシリカ被膜を形成した磁性酸化鉄粉末をｌＮ
−ＮａＯＨ水溶液３００１中に懸濁させ、この懸濁液に
ＩＭのＣｏ Ｓ Ｏａと２ＭのＦｅＳＯ４を含む水溶液
３．５Ｉ！、を３０分かけて滴下した。滴下終了後３０
°Ｃで６時間撹拌した後洗浄し、８０“Ｃで昼夜乾燥を
行って、それぞれのＣｏ被着磁性酸化鉄粉末を製造した
。Next, the magnetic iron oxide powder on which the silica film was formed was
- 3.5 I! of an aqueous solution containing IM of CoSOa and 2M of FeSO4 is suspended in a NaOH aqueous solution of 3001! was added dropwise over 30 minutes. 30 minutes after completion of dripping
After stirring at °C for 6 hours, the mixture was washed and dried at 80"C day and night to produce each Co-magnetized iron oxide powder.
このようにして得られたそれぞれのＣｏ被着磁性酸化鉄
粉末を使用し、
Ｃｏ被着磁性酸化鉄粉末 １００重量部ＶＡＧＨ
（Ｕ、Ｃ，Ｃ社性、塩化ビ ｌＯ〃ニル−酢酸ビニル
−ビニルア
ルコール共重合体）
バンデックスＴ−５２０１（大 ６ 〃日本インキ化
学工業社製、ポ
リウレタン、数平均分子量２
〜３万）
ミリスチン酸 ５ 〃Ｈ３−５００
（層重化社製、力 １ 〃−ボンブラック）
メチルイソブチルケン ８５〃トルエン
８５〃の組成からなる組成物を３１
容量のスチール製ボールミル中に入れ、これを７２時間
回転させ、よく分散させて磁性ペーストを調製した。そ
の後、この磁性ペーストに、トルエン４０重量部とコロ
ネー１−Ｌ（我国薬品工業社製、三官能性低分子量イソ
シアネート化合物）２重量部をさらに加え、磁性塗料を
調製した。この磁性塗料を厚さ１２μｍのポリエステル
フィルム上に、乾燥後の塗布厚が４μｍとなるように塗
布、乾燥し、鏡面加工処理を行った後、１／２インチ幅
に裁断して磁気テープをつくった。Using each of the Co-coated magnetic iron oxide powders obtained in this way, Co-coated magnetic iron oxide powder 100 parts by weight VAGH
(U, C, C-based, vinyl chloride lO-vinyl acetate-vinyl alcohol copolymer) Bandex T-5201 (large 6, manufactured by Nippon Ink Chemical Co., Ltd., polyurethane, number average molecular weight 20,000 to 30,000) Myristic acid 5 H3-500
(Manufactured by Layageika Co., Ltd., Chikara 1〃-Bon Black) Methylisobutylkene 85〃Toluene
A composition consisting of 85〃 composition is 31
The magnetic paste was prepared by placing the magnetic paste in a high capacity steel ball mill and rotating it for 72 hours to ensure good dispersion. Thereafter, 40 parts by weight of toluene and 2 parts by weight of Coronet 1-L (manufactured by Gakoku Yakuhin Kogyo Co., Ltd., a trifunctional low molecular weight isocyanate compound) were further added to this magnetic paste to prepare a magnetic paint. This magnetic paint was applied onto a polyester film with a thickness of 12 μm so that the coating thickness after drying was 4 μm, dried, mirror-finished, and then cut into 1/2 inch width to make magnetic tape. Ta.
比較例１
実施例１〜５において、γ−Ｆｅ、Ｏ，粉末の粒子表面
のシリカ被膜の形成を省いた以外は、実施例１と同様に
してＣｏ被着磁性酸化鉄粉末を製造し、このＣｏ被着磁
性酸化鉄粉末を、実施例１〜５で使用したＣｏ被着磁性
酸化鉄粉末に代えて同量使用した以外は、実施例１〜５
と同様にして磁気テープをつくった。Comparative Example 1 Co-adhered magnetic iron oxide powder was produced in the same manner as in Example 1, except that the formation of a silica film on the particle surface of the γ-Fe, O, powder was omitted in Examples 1 to 5. Examples 1 to 5 except that the same amount of Co magnetized iron oxide powder used in Examples 1 to 5 was used in place of the Co magnetized iron oxide powder used in Examples 1 to 5.
I made magnetic tape in the same way.
各実施例および比較例で得られたＣｏ被着磁性酸化鉄粉
末のケイ素の被着量、保磁力、飽和磁化および１２０°
Ｃの真空中での熱処理前後の消去特性を調べた。消去特
性はＩＯＫエルステッドの磁界中で飽和磁化後、ＩＫエ
ルステッドの交流磁界中で消去したときの残留磁化を測
定して調べた。Amount of silicon deposited, coercive force, saturation magnetization, and 120° of Co-magnetized iron oxide powder obtained in each example and comparative example
The erasing characteristics of C before and after heat treatment in vacuum were investigated. Erasing characteristics were investigated by measuring residual magnetization when erased in an IK Oersted alternating current magnetic field after saturation magnetization in an IOK Oersted magnetic field.
下記第１表はその結果である。Table 1 below shows the results.
第 １ 表
また、各実施例および各比較例で得られた磁気テープに
ついて、保磁力、最大残留磁束密度、角型を測定し、Ｖ
ＴＲデツキによる消去特性を調べた。Table 1 In addition, coercive force, maximum residual magnetic flux density, and square shape were measured for the magnetic tapes obtained in each example and each comparative example, and V
The erasing characteristics of the TR deck were investigated.
下記第２表はその結果である。Table 2 below shows the results.
第２表
〔発明の効果〕
前記第１表および第２表から明らかなように、実施例工
ないし５で得られたＣｏ被着磁性酸化鉄粉末は、従来の
Ｃｏ被着磁性酸化鉄粉末（比較例１）に比し、熱処理後
の消去特性の劣化がなく、また実施例工ないし５で得ら
れた磁気テープは、比較例１で得られた磁気テープに比
し、角型が高くて、消去特性がよ（、このことからこの
発明のＣｏ被着磁性酸化鉄粉末は、消去特性がよくて熱
処理しても消去特性の劣化がなく、このＣｏ被着磁性酸
化鉄粉末を使用して得られる磁気記録媒体は、消去特性
が一段と向上されていることがわかる。Table 2 [Effects of the Invention] As is clear from the above Tables 1 and 2, the Co-coated magnetic iron oxide powders obtained in Examples Work to 5 are different from the conventional Co-coated magnetic iron oxide powders ( Compared to Comparative Example 1), there was no deterioration in erasing characteristics after heat treatment, and the magnetic tapes obtained in Examples 1 to 5 had a higher square shape than the magnetic tape obtained in Comparative Example 1. , it has good erasing properties (from this, the Co-magnetized iron oxide powder of the present invention has good erasing properties and does not deteriorate even after heat treatment, and this Co-magnetized iron oxide powder can be used It can be seen that the erasing characteristics of the obtained magnetic recording medium are further improved.
特許出願人 日立マクセル株式会社Patent applicant: Hitachi Maxell, Ltd.
Claims (6)
被膜を形成し、このケイ素化合物からなる被膜上にＣｏ
フェライトからなる被膜を形成してなるＣｏ被着磁性酸
化鉄粉末。1. A coating made of a silicon compound is formed on the particle surface of magnetic iron oxide powder, and Co is deposited on the coating made of a silicon compound.
Co magnetized iron oxide powder formed by forming a film made of ferrite.
からなる被膜が、Ｃｏ被着磁性酸化鉄粉末全体に対する
重量比で０．００５〜０．０３のＳｉを含有し、さらに
その上のＣｏフェライトからなる被膜が、Ｃｏ被着磁性
酸化鉄粉末全体に対する重量比で０．０１〜０．１０の
Ｃｏを含有してなる請求項１記載のＣｏ被着磁性酸化鉄
粉末。2. The coating made of a silicon compound formed on the particle surface of the magnetic iron oxide powder contains Si in a weight ratio of 0.005 to 0.03 with respect to the entire Co-coated magnetic iron oxide powder, and further consists of Co ferrite thereon. 2. The Co-magnetic iron oxide powder according to claim 1, wherein the coating contains Co in a weight ratio of 0.01 to 0.10 with respect to the entire Co-magnetized iron oxide powder.
からなる被膜が、ケイ素酸化物またはケイ素含水酸化物
である請求項１および２記載のＣｏ被着磁性酸化鉄粉末
。3. Co magnetizable iron oxide powder according to claims 1 and 2, wherein the coating made of a silicon compound formed on the particle surface of the magnetic iron oxide powder is a silicon oxide or a silicon hydrous oxide.
被膜を形成し、このケイ素化合物からなる被膜上にＣｏ
フェライトからなる被膜を形成してなるＣｏ被着磁性酸
化鉄粉末を、磁性層中に含有させたことを特徴とする磁
気記録媒体。4. A coating made of a silicon compound is formed on the particle surface of magnetic iron oxide powder, and Co is deposited on the coating made of a silicon compound.
1. A magnetic recording medium characterized in that a magnetic layer contains Co-adherable iron oxide powder formed by forming a coating made of ferrite.
成したケイ素化合物からなる被膜が、Ｃｏ被着磁性酸化
鉄粉末全体に対する重量比で０．００５〜０．０３のＳ
ｉを含有し、さらにその上のＣｏフェライトからなる被
膜が、Ｃｏ被着磁性酸化鉄粉末全体に対する重量比で０
．０１〜０．１０のＣｏを含有してなる請求項５記載の
磁気記録媒体。5. A coating made of a silicon compound formed on the particle surface of the magnetic iron oxide powder contained in the magnetic layer has an S content of 0.005 to 0.03 in weight ratio to the entire Co-coated magnetic iron oxide powder.
The coating made of Co ferrite on top of the Co ferrite has a weight ratio of 0 to the entire Co-coated magnetic iron oxide powder.
．． 6. The magnetic recording medium according to claim 5, containing Co of 0.01 to 0.10.
成されたケイ素化合物からなる被膜が、ケイ素酸化物ま
たはケイ素含水酸化物である請求項４および５記載の磁
気記録媒体。6. 6. The magnetic recording medium according to claim 4, wherein the coating made of a silicon compound formed on the surface of the particles of magnetic iron oxide powder contained in the magnetic layer is a silicon oxide or a silicon hydrate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63066916A JPH01239820A (en) | 1988-03-19 | 1988-03-19 | Co-coating magnetic iron oxide powder and magnetic recording medium using same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63066916A JPH01239820A (en) | 1988-03-19 | 1988-03-19 | Co-coating magnetic iron oxide powder and magnetic recording medium using same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01239820A true JPH01239820A (en) | 1989-09-25 |
Family
ID=13329775
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63066916A Pending JPH01239820A (en) | 1988-03-19 | 1988-03-19 | Co-coating magnetic iron oxide powder and magnetic recording medium using same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01239820A (en) |
-
1988
- 1988-03-19 JP JP63066916A patent/JPH01239820A/en active Pending
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