JPH0612725B2 - Method of manufacturing magnetic material - Google Patents
Method of manufacturing magnetic materialInfo
- Publication number
- JPH0612725B2 JPH0612725B2 JP59143356A JP14335684A JPH0612725B2 JP H0612725 B2 JPH0612725 B2 JP H0612725B2 JP 59143356 A JP59143356 A JP 59143356A JP 14335684 A JP14335684 A JP 14335684A JP H0612725 B2 JPH0612725 B2 JP H0612725B2
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- Prior art keywords
- magnetic
- acid
- present
- dispersant
- parts
- Prior art date
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- Compounds Of Iron (AREA)
- Pigments, Carbon Blacks, Or Wood Stains (AREA)
- Paints Or Removers (AREA)
- Magnetic Record Carriers (AREA)
- Hard Magnetic Materials (AREA)
Description
【発明の詳細な説明】 本発明は磁性材料の製造方法に関するものである。従来
磁性材料の製造に当って粉状磁性物質の分散性を向上さ
せる目的で使用される分散剤としては、脂肪アミン石ケ
ン、多価アルコール脂肪酸エステル、ポリオキシエチレ
ンアルキルエーテルフォスフェート、ポリオキシエチレ
ンアルキルフェニルエーテルフォスフェートなどが知ら
れており、中でも特定のポリオキシエチレンアルキルエ
ーテルフォスフェート、ポリオキシエチレンアルキルフ
ェニルエーテルフォスフェートは望ましいものとして知
られている。The present invention relates to a method for manufacturing a magnetic material. Dispersants conventionally used for the purpose of improving the dispersibility of powdery magnetic substances in the production of magnetic materials include fatty amine soaps, polyhydric alcohol fatty acid esters, polyoxyethylene alkyl ether phosphates, and polyoxyethylene. Alkylphenyl ether phosphates and the like are known, and among them, specific polyoxyethylene alkyl ether phosphates and polyoxyethylene alkylphenyl ether phosphates are known to be desirable.
しかしながら、近時磁性材料の性能向上の要望が高まる
につれて特に磁性粉末に適合した分散剤の開発が強く望
まれるようになってきた。すなわち、γ−酸化鉄の分散
には上記リン酸エステルが優れているが、Co含有磁性酸
化鉄にはいまだ充分分散効果を発揮する分散剤は見い出
されていない。However, with the recent increasing demand for improved performance of magnetic materials, the development of dispersants particularly suited to magnetic powders has been strongly desired. That is, although the above-mentioned phosphoric acid ester is excellent in the dispersion of γ-iron oxide, a dispersant which exerts a sufficient dispersion effect on Co-containing magnetic iron oxide has not yet been found.
本発明者はCo含有磁性酸化鉄の分散に優れたものを開発
すべく種々検討の結果、後記の一般式で示される化合物
が特にCo含有磁性酸化鉄の分散性の改善に特に好適なも
のであり、それによって磁気記録媒体の磁気特性の改善
をもたらし得ることの知見を得、本発明に至ったもので
ある。すなわち、本願発明は、 一般式 ＲＣＯＮＨ（Ｒ′ＮＲ″）ｎＲ′ＮＨＲ″ （但し、式中Ｒは炭素数１１〜２１のアルキル基、アル
ケニル基、R′はC2H4またはC3H6、R″はＨまたはOCRで
少なくとも１個はＨ、ｎは０または１〜４の整数）で示
される高級脂肪酸とポリアルキレンポリアミンとの縮合
物またはそれらの有機酸塩、鉱酸塩の少なくとも一種の
水溶液あるいは溶剤を使用した中に粉状磁性物質を浸漬
し、過、乾燥することを特徴とする磁性材料の製造方
法に関するものである。As a result of various investigations by the present inventors to develop an excellent dispersion of Co-containing magnetic iron oxide, the compound represented by the following general formula is particularly suitable for improving the dispersibility of Co-containing magnetic iron oxide. The present invention has been made based on the knowledge that the magnetic characteristics of the magnetic recording medium can be improved thereby. That is, the invention of the present application is based on the general formula RCONH (R′NR ″) n R′NHR ″ (wherein R is an alkyl group or alkenyl group having 11 to 21 carbon atoms, and R ′ is C 2 H 4 or C 3 H 6 , R ″ is H or OCR, at least one of which is H, n is 0 or an integer of 1 to 4), a condensate of a higher fatty acid and a polyalkylene polyamine, or at least an organic acid salt or a mineral acid salt thereof. The present invention relates to a method for producing a magnetic material, which comprises immersing a powdery magnetic substance in a kind of aqueous solution or solvent and then drying and immersing it.
本願発明に係わる一般式で示される化合物は高級脂肪酸
１モルないし４モルとポリアルキレンポリアミン１モル
とを混合し、これを１００℃ないし２００℃好ましくは
１５０℃ないし２００℃にて公知の方法でアマイド化反
応を充分行うことによって容易に得られる高級脂肪酸と
ポリアルキレンポリアミンとの縮合物である。The compound represented by the general formula according to the present invention is obtained by mixing 1 mol to 4 mol of a higher fatty acid and 1 mol of a polyalkylenepolyamine, and mixing the mixture at 100 ° C. to 200 ° C., preferably 150 ° C. to 200 ° C. by a known method. It is a condensate of a higher fatty acid and a polyalkylene polyamine, which can be easily obtained by sufficiently carrying out a chemical reaction.
本願発明に使用される高級脂肪酸類は、炭素数１２〜２
２の飽和脂肪酸もしくは不飽和脂肪酸で具体的には、ラ
ウリン酸、ミリスチン酸、パルミチン酸、ステアリン
酸、１２−ヒドロステアリン酸、オレイン酸、リシノー
ル酸、エルカ酸およびベヘン酸などが挙げられ、ポリア
ルキレンポリアミン類としてはエチレンジアミン、ジエ
チレントリアミン、トリエチレンテトラアミン、テトラ
エチレンペンタアミン、プロピレンジアミンおよびジプ
ロピレントリアミンなどを挙げることができる。The higher fatty acids used in the present invention have 12 to 2 carbon atoms.
Specific examples of the saturated fatty acid or unsaturated fatty acid of 2 include lauric acid, myristic acid, palmitic acid, stearic acid, 12-hydrostearic acid, oleic acid, ricinoleic acid, erucic acid and behenic acid. Examples of polyamines include ethylenediamine, diethylenetriamine, triethylenetetraamine, tetraethylenepentamine, propylenediamine and dipropylenetriamine.
なお、一般式に表される化合物の塩としては酢酸、蟻
酸、クエン酸、乳酸、プロピオン酸およびモノクロル酢
酸などの有機酸塩、または塩酸、硝酸、硫酸、燐酸など
の鉱酸塩などを挙げることができる。Examples of the salt of the compound represented by the general formula include organic acid salts such as acetic acid, formic acid, citric acid, lactic acid, propionic acid and monochloroacetic acid, or mineral acid salts such as hydrochloric acid, nitric acid, sulfuric acid and phosphoric acid. You can
本願発明の磁性材料の製造に使用される粉状磁性物質と
してはγ-Fe2O3、マグネタイト(Fe3O4)、ベルトライド
系酸化鉄(FeOX,1.33＜×＜1.5)、それらがコバルト、マ
ンガン、ニッケル、亜鉛、クロムなどで変性されたも
の、金属鉄やその合金、強磁性二酸化クロムなどの粉末
を挙げることができる。それらはそれぞれ単独使用して
もあるいはそれらを適宜混用したりすることもできる。As the powdery magnetic substance used in the production of the magnetic material of the present invention, γ-F e2 O 3 , magnetite (F e3 O 4 ), beltride iron oxide (F e O X , 1.33 <× <1.5), Examples thereof include those modified with cobalt, manganese, nickel, zinc, chromium and the like, powders of metallic iron and its alloys, ferromagnetic chromium dioxide and the like. Each of them can be used alone, or can be appropriately mixed.
本願発明方法において一般式で示される化合物（以下本
発明の分散剤という）を含有せしめた磁性材料を製造す
るには(1)本発明の分散剤を水に溶解または懸濁した水
性液あるいはトルエン、キシレン、ケロシン、メチルエ
チルケトン、メチルイソブチルケトン、シクロヘキサノ
ン、酢酸エチルなどの有機溶剤に溶解または懸濁した非
水性液に粉状磁性物質を浸漬して磁性粉の粒子表面に本
発明の分散剤を吸着させる方法。(2)前記(1)の場合の水
性液または非水性液を粉状磁性物質に噴霧して本発明の
分散剤を粉状磁性物質の粒子表面に吸着させる方法。
(3)粉状物質を樹脂バインダーに分散させて磁性塗料を
製造する際に本発明の分散剤を配合する方法などによっ
て行うことができる。To produce a magnetic material containing the compound represented by the general formula (hereinafter referred to as the dispersant of the present invention) in the method of the present invention (1) an aqueous liquid or toluene in which the dispersant of the present invention is dissolved or suspended in water The powdery magnetic substance is immersed in a non-aqueous liquid dissolved or suspended in an organic solvent such as xylene, kerosene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, or ethyl acetate to adsorb the dispersant of the present invention on the surface of magnetic powder particles. How to make. (2) A method of spraying the aqueous liquid or non-aqueous liquid in the case of the above (1) on a powdery magnetic substance to adsorb the dispersant of the present invention on the particle surface of the powdery magnetic substance.
(3) It can be carried out by a method of blending the dispersant of the present invention when a magnetic coating material is produced by dispersing a powdery substance in a resin binder.
本発明において前記一般式に係わる本発明の分散剤の添
加量は、粉状磁性物質の重量基準で0.1〜6.0％好ましく
は0.5〜4.0％である。添加量が前記範囲より少なきに過
ぎると所望の効果が得られず、また多きに過ぎると例え
ば磁性塗膜の強度が損われたり、分散剤が塗膜表面にブ
リーディングして各種の欠点が発生したりして好ましく
ない。本発明において使用される樹脂バインダーとして
は例えば、ビニル系、セルロース系、ウレタン系、エポ
キシ系、フェノキシ系及びアクリル系樹脂などを挙げる
ことができる。In the present invention, the amount of the dispersant of the present invention according to the above general formula added is 0.1 to 6.0%, preferably 0.5 to 4.0%, based on the weight of the powdery magnetic substance. If the addition amount is less than the above range, the desired effect cannot be obtained, and if it is too large, for example, the strength of the magnetic coating film is impaired, or the dispersant causes various defects by bleeding on the coating surface. It is not preferable. Examples of the resin binder used in the present invention include vinyl-based, cellulose-based, urethane-based, epoxy-based, phenoxy-based and acrylic-based resins.
本発明によれば後記実施例からも明らかなように、本発
明以外の分散剤を使用した磁性材料に比べて特に粉状磁
性物質の樹脂バインダーとのなじみが改善されて分散性
が向上し、磁気特性の優れた磁気記録媒体が得られる。According to the present invention, as will be apparent from the examples described below, the dispersibility is improved by improving the familiarity with the resin binder of the powdery magnetic substance as compared with the magnetic material using the dispersant other than the present invention, A magnetic recording medium having excellent magnetic properties can be obtained.
実施例1. （１）本発明に係わる分散剤の製造 Ａ．攪拌器、温度計、窒素導入管、冷却管を付した四つ
口フラスコにオレイン酸１モル（２８２部）とテトラエ
チレンペンタアミン１モル（１８９部）とを仕込み、１
７０℃で５時間脱水反応をさせ、オレイン酸とテトラエ
チレンペンタアミンのモノアマイド（４５４部）の液状
物質を得た。本発明に係わる分散剤Ａとする。Example 1. (1) Production of Dispersant According to the Present Invention A. A four-necked flask equipped with a stirrer, a thermometer, a nitrogen introducing tube, and a cooling tube was charged with 1 mol (282 parts) of oleic acid and 1 mol (189 parts) of tetraethylenepentamine and 1 mol.
A dehydration reaction was carried out at 70 ° C. for 5 hours to obtain a liquid substance of monoamide (454 parts) of oleic acid and tetraethylenepentamine. This is Dispersant A according to the present invention.
Ｂ．分散剤Ａと同様の装置および方法で、オレイン酸２
モル（５６４部）とトリエチレンテトラアミン１モル
（１４６部）とを反応させ、オレイン酸とトリエチレン
テトラアミンのジアマイド（６７４部）の液状物質を得
た。本発明に係わる分散剤Ｂとする。B. Oleic acid 2 was prepared using the same device and method as the dispersant A.
Mol (564 parts) and 1 mol of triethylenetetraamine (146 parts) were reacted to obtain a liquid substance of amide acid (674 parts) of oleic acid and triethylenetetraamine. This is Dispersant B according to the present invention.
Ｃ．分散剤Ａと同様の装置および方法で、ステアリン酸
１モル（２８４部）とジエチレントリアミン１モル（１
０３部）を反応させ、ステアリン酸とジエチレントリア
ミンのモノアマイド（３６９部）の固状物質（常温に
て）を得た。本発明に係わる分散剤Ｃとする。C. Using the same device and method as for Dispersant A, 1 mol of stearic acid (284 parts) and 1 mol of diethylenetriamine (1 part)
(03 parts) to give a solid substance (at room temperature) of stearic acid and diethylenetriamine monoamide (369 parts). This is Dispersant C according to the present invention.
（２）磁性塗料の調製 磁性粉末はCO-γ-Fe2O3（保磁力Ｈｃ６０００ｅ平均長
軸径約0.4μm、軸比約１０：１）を用いて下記の割合で
配合し、ボールミルで十分混練して磁性塗料を調製し
た。(2) Preparation of magnetic paint The magnetic powder was blended with C O -γ-F e2 O 3 (coercive force H c 6000 e average major axis diameter of about 0.4 μm, axial ratio of about 10: 1) in the following proportions. Then, the mixture was thoroughly kneaded with a ball mill to prepare a magnetic paint.
CO-γ-Fe2O3………………………１００重量部 塩化ビニル−酢酸ビニル共重合体…１０ 〃 ポリウレタン樹脂……………………２０ 〃 本発明の分散剤または比較分散剤……３ 〃 トルエン……………………………１００重量部 メチルエチルケトン………………１００ 〃 （３）磁気記録媒体の製造 (2)で得られた磁性塗料をポリエステルフィルムに通常
の方法で塗布、配向乾燥し約６μ厚の磁性塗膜を形成し
た磁気記録媒体を得た。C O -γ-F e2 O 3 ……………………………… 100 parts by weight Vinyl chloride-vinyl acetate copolymer ・ ・ ・ 10〃 Polyurethane resin …………………………………… 20 〃 Dispersant of the present invention or Comparative dispersant …… 3 〃 Toluene …………………………………… 100 parts by weight Methyl ethyl ketone ………… 100 〃 (3) Manufacture of magnetic recording medium The magnetic paint obtained in (2) was used as polyester. A magnetic recording medium having a magnetic coating film with a thickness of about 6 μm was obtained by coating the film on the film by a conventional method, and orientation drying.
（４）磁気記録媒体の特性 本発明に係わる分散剤Ａ，ＢおよびＣを使用した磁気記
録媒体について保磁力(Hc)、残留磁束密度(Br)、飽和磁
束密度(Bm)、角形比(Br/Bm)および配向性(OR)の測定結
果を第１表に示す。(4) Characteristics of magnetic recording medium Coercive force (H c ), residual magnetic flux density (B r ), saturation magnetic flux density (B m ), prismatic shape for magnetic recording media using the dispersants A, B and C according to the present invention. Table 1 shows the measurement results of the ratio (B r / B m ) and the orientation (OR).
実施例2. （１）本発明に係わる分散剤の製造 Ｄ．分散剤Ａと同様の装置および方法で、ラウリン酸１
モル（２００部）とプロピレンジアミン１モル（７４
部）を反応させ、ラウリン酸とプロピレンジアミンのモ
ノアマイド（２５６部）の固状物質（常温にて）を得
た。本発明に係わる分散剤Ｄとする。 Example 2. (1) Production of dispersant according to the present invention D. Lauric acid 1 was prepared by the same device and method as the dispersant A.
Mol (200 parts) and propylenediamine 1 mol (74
Part) was reacted to obtain a solid substance (at room temperature) of monoamide (256 parts) of lauric acid and propylenediamine. This is Dispersant D according to the present invention.
Ｅ．分散剤Ａと同様の装置および方法で、エルカ酸１モ
ル（３３９部）とトリエチレンテトラアミン１モル（１
４６部）を反応させ、エルカ酸とトリエチレンテトラア
ミンのモノアマイド（４６７部）を得、さらに酢酸を用
い中和して液状物質を得た。E. Using the same device and method as for the dispersant A, 1 mol of erucic acid (339 parts) and 1 mol of triethylenetetraamine (1 part) were used.
46 parts) were reacted to obtain a monoamide of erucic acid and triethylenetetraamine (467 parts) and further neutralized with acetic acid to obtain a liquid substance.
本発明に係わる分散剤Ｅとする。This is Dispersant E according to the present invention.
（２）粉状磁性物質の処理 本発明に係わる分散剤ＤまたはＥ３重量部を１０００重
量部の水に溶解し、その水溶液の中にCo含有磁性酸化鉄
１００重量部を加え、充分攪拌した後、ロ過し得られた
ロ過物を８０℃で２４時間乾燥して磁気記録媒体用磁性
粉末を得た。(2) Treatment of powdered magnetic substance Dispersant D or E of the present invention (3 parts by weight) is dissolved in 1000 parts by weight of water, 100 parts by weight of Co-containing magnetic iron oxide is added to the aqueous solution, and the mixture is thoroughly stirred. The filtered product was dried at 80 ° C. for 24 hours to obtain a magnetic powder for a magnetic recording medium.
（３）磁性塗料の調製 (2)で処理したCo含有磁性酸化鉄を用いて下記の割割合
で配合し、ボールミルで十分混練して磁性塗料を調製し
た。(3) Preparation of magnetic paint The Co-containing magnetic iron oxide treated in (2) was blended in the following proportions and thoroughly kneaded in a ball mill to prepare a magnetic paint.
粉末…………………………………１００重量部 塩化ビニル−酢酸ビニル共重合体…１５ 〃 ポリウレタン樹脂……………………１５ 〃 トルエン……………………………１００ 〃 メチルイソブチルケトン…………１００ 〃 （４）磁気記録媒体の製造 (3)で得られた磁性塗料をポリエステルフィルムに通常
の方法で塗布、配向乾燥し約６μ厚の磁性塗膜を形成し
た磁気記録媒体を得た。Powder …………………………………… 100 parts by weight Vinyl chloride-vinyl acetate copolymer… 15〃 Polyurethane resin …………………… 15〃 Toluene ………………………… …… 100 〃 Methyl isobutyl ketone ………… 100 〃 (4) Manufacture of magnetic recording medium The magnetic paint obtained in (3) is applied to a polyester film by the usual method, and orientation-dried to give a magnetic coating film of about 6μ thick. A magnetic recording medium having the above-mentioned structure was obtained.
（５）磁気記録媒体の特性 実施例3. （１）粉状磁性物質の処理 本発明に係わる分散剤ＡまたはＣ３重量部をトルエン１
０００重量部に溶解し、その液中にCo含有磁性酸化鉄１
００重量部を加え、充分攪拌混合した後、ロ過し得られ
たロ過物を６０℃で２４時間乾燥して磁気記録媒体用磁
性粉末を得た。(5) Characteristics of magnetic recording media Example 3. (1) Treatment of powdered magnetic substance 1 part by weight of dispersant A or C according to the present invention was added to toluene 1
Dissolved in 000 parts by weight, Co-containing magnetic iron oxide 1
After adding 100 parts by weight and thoroughly mixing with stirring, the filtered product obtained by filtration was dried at 60 ° C. for 24 hours to obtain a magnetic powder for a magnetic recording medium.
（２）磁性塗料の調製 (1)で処理したCo含有磁性酸化鉄を用いて下記の割合で
配合し、ボールミルで十分混練して磁性塗料を調製し
た。(2) Preparation of magnetic paint The Co-containing magnetic iron oxide treated in (1) was blended in the following proportions and thoroughly kneaded in a ball mill to prepare a magnetic paint.
粉末…………………………………１００重量部 塩化ビニル−酢酸ビニル共重合体…１０ 〃 ポリウレタン樹脂……………………２０ 〃 トルエン……………………………１００ 〃 シクロヘキサノン…………………１００ 〃 （３）磁気記録媒体の製造 (2)で得られた磁性塗料をポリエステルフィルムに通常
の方法で塗布、配向乾燥し約６μ厚の磁性塗膜を形成し
た磁気記録媒体を得た。Powder ……………………………………… 100 parts by weight Vinyl chloride-vinyl acetate copolymer… 10〃 Polyurethane resin …………………… 20〃 Toluene ……………………………… …… 100 〃 Cyclohexanone …………………… 100 〃 (3) Manufacture of magnetic recording medium The magnetic coating obtained in (2) is applied to a polyester film by a conventional method, oriented and dried to give a magnetic coating of about 6 μm thick. A magnetic recording medium having a film formed thereon was obtained.
（４）磁気記録媒体の特性 (4) Characteristics of magnetic recording media
Claims (1)
ケニル基、Ｒ′はＣ２Ｈ４またはＣ３Ｏ６、Ｒ″はＨま
たはＯＣＲで少なくとも１個はＨ、ｎは０または１〜４
の整数）で示される高級脂肪酸とポリアルキレンポリア
ミンとの縮合物またはそれらの有機酸塩、鉱酸塩の少な
くとも一種の水溶液あるいは溶剤を使用した中に粉状磁
性物質を浸漬し、濾過、乾燥することを特徴とする磁性
材料の製造方法。1. The general formula RCONH (R′NR ″) n R′NHR ″ (wherein R is an alkyl group or alkenyl group having 11 to 21 carbon atoms, and R ′ is C 2 H 4 or C 3 O 6 , R ″ is H or OCR and at least one is H and n is 0 or 1-4.
The powdery magnetic substance is immersed in a condensate of a higher fatty acid and a polyalkylene polyamine represented by the formula) or an aqueous solution or solvent of at least one organic acid salt or mineral acid salt thereof, filtered, and dried. A method of manufacturing a magnetic material, comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59143356A JPH0612725B2 (en) | 1984-07-12 | 1984-07-12 | Method of manufacturing magnetic material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59143356A JPH0612725B2 (en) | 1984-07-12 | 1984-07-12 | Method of manufacturing magnetic material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6123305A JPS6123305A (en) | 1986-01-31 |
| JPH0612725B2 true JPH0612725B2 (en) | 1994-02-16 |
Family
ID=15336879
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59143356A Expired - Fee Related JPH0612725B2 (en) | 1984-07-12 | 1984-07-12 | Method of manufacturing magnetic material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0612725B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0740364B2 (en) * | 1985-08-08 | 1995-05-01 | オリンパス光学工業株式会社 | Optical pickup |
| JPH0689368B2 (en) * | 1985-12-25 | 1994-11-09 | 東邦化学工業株式会社 | Method for producing metal magnetic powder for magnetic recording |
-
1984
- 1984-07-12 JP JP59143356A patent/JPH0612725B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6123305A (en) | 1986-01-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |