JPS6343808B2 - - Google Patents
Info
- Publication number
- JPS6343808B2 JPS6343808B2 JP55132142A JP13214280A JPS6343808B2 JP S6343808 B2 JPS6343808 B2 JP S6343808B2 JP 55132142 A JP55132142 A JP 55132142A JP 13214280 A JP13214280 A JP 13214280A JP S6343808 B2 JPS6343808 B2 JP S6343808B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- recording
- recording medium
- magnetic recording
- powder
- 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
- 229910000859 α-Fe Inorganic materials 0.000 claims description 14
- 239000000843 powder Substances 0.000 claims description 13
- 239000011230 binding agent Substances 0.000 claims description 9
- 239000003973 paint Substances 0.000 claims description 9
- 239000004094 surface-active agent Substances 0.000 claims description 7
- -1 C12 hydrocarbon Chemical class 0.000 claims description 5
- 239000011347 resin Substances 0.000 claims description 3
- 229920005989 resin Polymers 0.000 claims description 3
- 239000004215 Carbon black (E152) Substances 0.000 claims description 2
- 229930195733 hydrocarbon Natural products 0.000 claims description 2
- 150000003014 phosphoric acid esters Chemical class 0.000 claims 1
- 239000010419 fine particle Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 230000005415 magnetization Effects 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- AJCDFVKYMIUXCR-UHFFFAOYSA-N oxobarium;oxo(oxoferriooxy)iron Chemical compound [Ba]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O AJCDFVKYMIUXCR-UHFFFAOYSA-N 0.000 description 6
- 238000000576 coating method Methods 0.000 description 4
- 239000006247 magnetic powder Substances 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- 229910019142 PO4 Inorganic materials 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 239000010452 phosphate Substances 0.000 description 3
- 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 2
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 2
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000011247 coating layer Substances 0.000 description 2
- 229920001577 copolymer Polymers 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 229940067606 lecithin Drugs 0.000 description 2
- 235000010445 lecithin Nutrition 0.000 description 2
- 239000000787 lecithin Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910052712 strontium Inorganic materials 0.000 description 2
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 2
- 230000003746 surface roughness Effects 0.000 description 2
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 1
- ZJCCRDAZUWHFQH-UHFFFAOYSA-N Trimethylolpropane Chemical compound CCC(CO)(CO)CO ZJCCRDAZUWHFQH-UHFFFAOYSA-N 0.000 description 1
- 239000003093 cationic surfactant Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- XMNVMZIXNKZAJB-UHFFFAOYSA-N iron(3+);lead(2+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Fe+3].[Fe+3].[Pb+2].[Pb+2] XMNVMZIXNKZAJB-UHFFFAOYSA-N 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 239000006249 magnetic particle Substances 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052752 metalloid Inorganic materials 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- DVKJHBMWWAPEIU-UHFFFAOYSA-N toluene 2,4-diisocyanate Chemical compound CC1=CC=C(N=C=O)C=C1N=C=O DVKJHBMWWAPEIU-UHFFFAOYSA-N 0.000 description 1
- 229910052725 zinc 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
- G11B5/7013—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 dispersing agent
Description
【発明の詳細な説明】
本発明は、高記録密度の磁気記録媒体の製造に
適した磁気記録媒体用磁性塗料に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic coating material for magnetic recording media suitable for manufacturing high recording density magnetic recording media.
磁気記録は、一般に記録媒体の面内長手方向の
磁化を用いる方式によつている。しかし、この面
内長手方向の磁化を用いる記録方式にあつては、
記録の高密度化を図ろうとすると、記録媒体内の
減磁界が増加するため、記録密度をそれ程向上さ
せることはできない。 Magnetic recording generally relies on a method that uses magnetization in the in-plane longitudinal direction of a recording medium. However, in a recording method that uses magnetization in the in-plane longitudinal direction,
If an attempt is made to increase the recording density, the demagnetizing field within the recording medium will increase, so the recording density cannot be improved that much.
そこで、このような不具合を解消するために、
近年、記録媒体の表面と垂直な方向の磁化を用い
る垂直磁気記録方式が提案されている。この垂直
磁気記録方式では、記録密度が高まる程、記録媒
体中の減磁界が減少するので、本質的に高密度記
録に適した記録方式と言える。 Therefore, in order to eliminate such problems,
In recent years, perpendicular magnetic recording methods have been proposed that use magnetization in a direction perpendicular to the surface of a recording medium. In this perpendicular magnetic recording method, as the recording density increases, the demagnetizing field in the recording medium decreases, so it can be said that it is essentially a recording method suitable for high-density recording.
しかして、このような垂直磁気記録方式を採用
するには、表面とは垂直な方向に磁化容易軸を有
する磁気記録媒体を必要とする。このような要望
を消す記録媒体として、従来、記録膜をCo−Cr
スパツタ膜で形成するものや記録膜を磁性微粒子
の塗布層で形成するものが提案されている。 However, in order to employ such a perpendicular magnetic recording method, a magnetic recording medium having an axis of easy magnetization in a direction perpendicular to the surface is required. Conventionally, the recording film was made of Co-Cr as a recording medium to meet these demands.
A recording film formed by sputtering and a recording film formed by a coating layer of magnetic fine particles have been proposed.
ところで、記録膜を磁性微粒子の塗布層で形成
するものにあつては、次のような製造方法が考え
られる。すなわち、磁性微粒子として、たとえば
BaFe12O19等の六方晶系フエライトを用いる。六
方晶系フエライトを用いる理由は、このフエライ
トは平板状をなしており、しかも磁化容易軸が板
面に垂直であるため、磁場配向処理によつて容易
に垂直配向を行ない得るからである。このような
六方晶系フエライトの磁性微粒子とバインダとを
混合し、これを非磁性テープの表面に塗布した
後、この塗布層を磁場中にその表面が磁界の方向
と直交するように配置することによつて各磁性微
粒子の磁化容易軸を磁界の方向に一致させて配列
させた後、塗料を乾燥させれば、垂直磁気記録に
適した記録媒体を得ることができる。 By the way, in the case where the recording film is formed by a coating layer of magnetic fine particles, the following manufacturing method can be considered. That is, as magnetic fine particles, for example
A hexagonal ferrite such as BaFe 12 O 19 is used. The reason for using hexagonal ferrite is that this ferrite has a flat plate shape and the axis of easy magnetization is perpendicular to the plate surface, so that it can be easily vertically aligned by magnetic field alignment treatment. After mixing such magnetic fine particles of hexagonal ferrite and a binder and coating the mixture on the surface of a non-magnetic tape, this coated layer is placed in a magnetic field so that the surface is perpendicular to the direction of the magnetic field. By arranging the easy axis of magnetization of each magnetic fine particle to match the direction of the magnetic field, and then drying the paint, a recording medium suitable for perpendicular magnetic recording can be obtained.
しかし、上述したいわゆる塗布法によつて垂直
磁気記録媒体を製造する場合には、次のような点
を考慮する必要がある。すなわち、従来の面内磁
気記録方式に較べて垂直磁気記録方式の利点を明
らかにするには、記録最小単位をサブミクロンの
オーダにする必要があり、そのためには、サブミ
クロン以下の磁性微粒子を用いる必要がある。こ
のような微小寸法の磁性微粒子は、単磁区構造、
すなわち微小な磁石となるため、互いに磁気的に
結合して二次凝集体を形成し易い。このため、バ
インダと混合してもバインダ内で均一に分散し難
い。前述の如く、高記録密度の磁気記録媒体を製
造するためには、バインダ内の磁性粉を磁界等に
よつて配向させる必要があり、このためには磁性
粉がバインダ内で１個１個独立している必要があ
る。このような理由から六方晶系フエライト粉が
バインダ内で均一に分散独立している磁性塗料の
出現が望まれている。 However, when manufacturing a perpendicular magnetic recording medium by the above-mentioned so-called coating method, the following points need to be taken into consideration. In other words, in order to clarify the advantages of perpendicular magnetic recording compared to conventional longitudinal magnetic recording, it is necessary to make the minimum recording unit on the order of submicrons. It is necessary to use it. Such small-sized magnetic particles have a single domain structure,
In other words, since they become minute magnets, they tend to magnetically couple with each other and form secondary aggregates. Therefore, even if mixed with a binder, it is difficult to disperse uniformly within the binder. As mentioned above, in order to manufacture magnetic recording media with high recording density, it is necessary to orient the magnetic powder in the binder using a magnetic field, etc., and for this purpose, the magnetic powder must be oriented individually within the binder. Must be. For these reasons, it is desired to develop a magnetic paint in which hexagonal ferrite powder is uniformly dispersed and independent within a binder.
本発明はこのような事情に鑑みてなされたもの
で、その目的とするところは、塗料中に六方晶系
フエライト微粒子が１個１個独立して存在し、も
つて磁界中での配向性を十分高めることができ、
合わせてフローイング効果、レベリング効果、フ
エライト微粒子の高充填効果、ならびに得られた
媒体の帯電防止化および高潤滑化に寄与できる磁
気記録媒体用磁性塗料を提供することにある。 The present invention was made in view of these circumstances, and its purpose is to ensure that each hexagonal ferrite fine particle exists independently in the paint, and that the orientation in a magnetic field is improved. can be sufficiently increased,
Another object of the present invention is to provide a magnetic paint for a magnetic recording medium that can contribute to a flowing effect, a leveling effect, a high filling effect of ferrite fine particles, and to making the obtained medium antistatic and highly lubricated.
本発明者らは、上記目的を達成するために種々
の実験を行なつた結果、バインダ、つまり樹脂結
着剤と六方晶系フエライト粉との混合物に、
一般式
または
但しＲ：C2〜C12の炭化水素
ｎ：３〜９
で示される少なくとも１種のリン酸エステル系界
面活性剤を添加混合すればよいことを見出した。 The present inventors conducted various experiments to achieve the above object, and as a result, the general formula: or However, it has been found that at least one phosphate ester surfactant represented by R: C2 to C12 hydrocarbon and n: 3 to 9 may be added and mixed.
本発明における六方晶系フエライト粉とは、バ
リウムフエライト，ストロンチウムフエライト等
の六方晶系の化合物粉体であり、Fe元素の一部
がTi，Co，Zn，In，Mn，Ge，Hb等の金属又は
半金属元素で置換されていてもよい（たとえば特
開昭54−86103号公報参照）。 The hexagonal ferrite powder in the present invention is a hexagonal compound powder such as barium ferrite and strontium ferrite, in which part of the Fe element is a metal such as Ti, Co, Zn, In, Mn, Ge, Hb, etc. Alternatively, it may be substituted with a metalloid element (see, for example, Japanese Patent Application Laid-Open No. 86103/1983).
さらに、樹脂結着剤は水溶性であつてもよい
し、非水溶性であつてもよい。 Furthermore, the resin binder may be water-soluble or water-insoluble.
以下、実施例によつて本発明を詳細に説明す
る。 Hereinafter, the present invention will be explained in detail with reference to Examples.
実施例 １
最大粒径0.4μm以下のバリウムフエライト粉を
塩ビ，酢ビ共重合体のメチルエチルケトン，トル
エン，シクロヘキサンの混合溶媒溶液中で混合
し、リン酸エステル系界面活性剤（化学式を下記
する。）
をフエライト粉100重量部に対して、2.5重量部添
加して、分散混合を行つたのち、ウレタン系硬化
剤（トリレンジイソシアナートのトリメチロール
プロパンアダクト体）を添加し、撹拌混合した。
このようにして、調製された磁性塗料を支持体上
に塗布、乾燥させて磁気記録媒体を作成した。こ
の際、塗布，乾燥の中間段階で磁界中を通過させ
ることにより、フエライト粉を配向させた。作成
された磁気記録媒体の配向率を測定したところ、
95％に達しており、しかも、磁性塗料のフローイ
ング特性、レベリング特性が優れているため、表
面の平滑性が極めて良く、表面粗さは高々0.5μm
であつた。また、帯電防止効果が高いため、塵埃
の付着量も少くなつていた。さらに潤滑効果が優
れるため、テープ状の磁気記録媒体の場合には走
行特性が良好であつた。Example 1 Barium ferrite powder with a maximum particle size of 0.4 μm or less was mixed in a mixed solvent solution of vinyl chloride and vinyl acetate copolymer, methyl ethyl ketone, toluene, and cyclohexane, and a phosphate ester surfactant (the chemical formula is shown below) was mixed. 2.5 parts by weight of was added to 100 parts by weight of ferrite powder, and the mixture was dispersed and mixed. Then, a urethane curing agent (trimethylolpropane adduct of tolylene diisocyanate) was added and mixed with stirring.
The thus prepared magnetic paint was applied onto a support and dried to produce a magnetic recording medium. At this time, the ferrite powder was oriented by passing it through a magnetic field at an intermediate stage between coating and drying. When we measured the orientation rate of the created magnetic recording medium, we found that
95%, and because the magnetic paint has excellent flowing and leveling properties, the surface is extremely smooth, with a surface roughness of at most 0.5μm.
It was hot. Furthermore, since the antistatic effect was high, the amount of dust adhesion was also reduced. Furthermore, because of the excellent lubrication effect, tape-shaped magnetic recording media had good running characteristics.
一方、比較のため従来より利用されている界面
活性剤であるレシチンを用いたところ、この場合
には配向率は高々82％に過ぎず、フローイング特
性，レベリング特性，帯電防止効果，潤滑効果も
劣り、高密度磁気記録媒体の製造には不向きであ
つた。 On the other hand, when lecithin, a conventionally used surfactant, was used for comparison, the orientation rate was only 82% at most, and the flowing properties, leveling properties, antistatic effect, and lubricating effect were also reduced. It was inferior and unsuitable for manufacturing high-density magnetic recording media.
実施例 ２
実施例１において、バリウムフエライト粉を体
積比で塩ビ，酢ビ共重含体およびウレタン系硬化
剤量に対して1.3：1.0，1.15：1.0，1.0：1.0，
1.0：0.9と変え、かつ界面活性剤として前記リン
酸エステル系界面活性剤を用いた場合には、いず
れも優ねた磁気特性，膜特性，走行性の記録媒体
が得られた。しかし従来より使用されているレシ
チン，カチオン系の界面活性剤を用いた場合に
は、高々1.0：1.0までしか上記フエライト粉末を
充填できなかつた。また配向率も高々85％であ
り、高密度磁気記録媒体としての性能を十分に満
たすものではなかつた。Example 2 In Example 1, the volume ratio of barium ferrite powder to the amount of vinyl chloride, vinyl acetate copolymer and urethane curing agent was 1.3:1.0, 1.15:1.0, 1.0:1.0,
When the ratio was changed to 1.0:0.9 and the phosphate ester surfactant was used as the surfactant, recording media with excellent magnetic properties, film properties, and running properties were obtained. However, when conventionally used lecithin and cationic surfactants were used, the ferrite powder could only be filled to a ratio of 1.0:1.0 at most. Furthermore, the orientation rate was at most 85%, which did not fully satisfy the performance as a high-density magnetic recording medium.
実施例 ３
実施例１におけるバリウムフエライト粉を粒径
0.2μm以下のBaO6.0（Fe1-0.1Ti0.05Co0.05）2O3のバ
リウムフエライト系磁性粉末に置き代え、実施例
１と同じ界面活性剤および樹脂結着剤を混合して
磁性塗料を作り、この磁性塗料を使つて実施例１
と同じ条件で磁気記録媒体を作成した。Example 3 The barium ferrite powder in Example 1 was
The same surfactant and resin binder as in Example 1 were used in place of BaO 6.0 (Fe 1-0.1 Ti 0.05 Co 0.05 ) 2 O 3 barium ferrite magnetic powder of 0.2 μm or less. Example 1 was prepared using this magnetic paint.
A magnetic recording medium was created under the same conditions.
この磁気記録媒体の配向率を測定したところ95
％であつた。また、表面粗さは0.5μm以下であつ
た。 When the orientation rate of this magnetic recording medium was measured, it was 95
It was %. Moreover, the surface roughness was 0.5 μm or less.
なお上記した実施例は、バリウムフエライト粉
を用いた場合であるが、磁性粉としてストロンチ
ウムフエライト粉、鉛フエライト粉の場合におい
ても同様の結果を得た。 Although the above-mentioned example uses barium ferrite powder, similar results were obtained when strontium ferrite powder and lead ferrite powder were used as the magnetic powder.
以上詳述したように、本発明によれば、高密度
記録媒体を製造するときに望まれる要件を全て満
足させ得る磁気記録媒体用磁性塗料を提供でき
る。 As detailed above, according to the present invention, it is possible to provide a magnetic paint for magnetic recording media that can satisfy all the requirements desired when manufacturing high-density recording media.
Claims (1)
び一般式 または 但しＲ：C2〜C12の炭化水素 ｎ：３〜９ で示される少なくとも１種のリン酸エステル系界
面活性剤を含んでなることを特徴とする磁気記録
媒体用磁性塗料。[Claims] 1. Resin binder, hexagonal ferrite powder, and general formula or A magnetic paint for a magnetic recording medium, comprising at least one phosphoric acid ester surfactant represented by R: C2 to C12 hydrocarbon; n: 3 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55132142A JPS5758229A (en) | 1980-09-22 | 1980-09-22 | Magnetic painting material for magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55132142A JPS5758229A (en) | 1980-09-22 | 1980-09-22 | Magnetic painting material for magnetic recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5758229A JPS5758229A (en) | 1982-04-07 |
| JPS6343808B2 true JPS6343808B2 (en) | 1988-09-01 |
Family
ID=15074337
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP55132142A Granted JPS5758229A (en) | 1980-09-22 | 1980-09-22 | Magnetic painting material for magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5758229A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107460802A (en) * | 2017-09-18 | 2017-12-12 | 杨小波 | A kind of bridge is squeegeeed restorative procedure |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5994231A (en) * | 1982-11-22 | 1984-05-30 | Fuji Photo Film Co Ltd | Magnetic recording medium |
| JPS61107533A (en) * | 1984-10-31 | 1986-05-26 | Konishiroku Photo Ind Co Ltd | Magnetic recording medium |
| JPH0618065B2 (en) * | 1985-04-30 | 1994-03-09 | コニカ株式会社 | Magnetic recording medium |
| JPS6252718A (en) * | 1985-08-30 | 1987-03-07 | Konishiroku Photo Ind Co Ltd | Magnetic recording medium |
| JPH0715740B2 (en) * | 1985-11-19 | 1995-02-22 | コニカ株式会社 | Magnetic recording medium |
| DE59106529D1 (en) * | 1990-11-01 | 1995-10-26 | Basf Magnetics Gmbh | Magnetic record carrier. |
-
1980
- 1980-09-22 JP JP55132142A patent/JPS5758229A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107460802A (en) * | 2017-09-18 | 2017-12-12 | 杨小波 | A kind of bridge is squeegeeed restorative procedure |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5758229A (en) | 1982-04-07 |
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