JPS6355727A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPS6355727A JPS6355727A JP19968386A JP19968386A JPS6355727A JP S6355727 A JPS6355727 A JP S6355727A JP 19968386 A JP19968386 A JP 19968386A JP 19968386 A JP19968386 A JP 19968386A JP S6355727 A JPS6355727 A JP S6355727A
- Authority
- JP
- Japan
- Prior art keywords
- carbon black
- magnetic
- magnetic layer
- oil absorption
- specific surface
- 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
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 57
- 239000006229 carbon black Substances 0.000 claims abstract description 48
- 238000010521 absorption reaction Methods 0.000 claims abstract description 21
- 235000019241 carbon black Nutrition 0.000 abstract description 45
- 230000009102 absorption Effects 0.000 abstract 3
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 239000003921 oil Substances 0.000 description 16
- 238000006243 chemical reaction Methods 0.000 description 14
- 239000011248 coating agent Substances 0.000 description 14
- 238000000576 coating method Methods 0.000 description 14
- 239000007788 liquid Substances 0.000 description 9
- 239000006247 magnetic powder Substances 0.000 description 9
- 239000002245 particle Substances 0.000 description 9
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 8
- 229910052799 carbon Inorganic materials 0.000 description 8
- 229920005989 resin Polymers 0.000 description 8
- 239000011347 resin Substances 0.000 description 8
- -1 H3-500 Chemical compound 0.000 description 7
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 239000011230 binding agent Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 4
- 229920001228 polyisocyanate Polymers 0.000 description 4
- 239000005056 polyisocyanate Substances 0.000 description 4
- 230000003746 surface roughness Effects 0.000 description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 229920001577 copolymer Polymers 0.000 description 3
- 229910052593 corundum Inorganic materials 0.000 description 3
- 239000010431 corundum Substances 0.000 description 3
- 239000012948 isocyanate Substances 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 239000003973 paint Substances 0.000 description 3
- 239000013034 phenoxy resin Substances 0.000 description 3
- 229920006287 phenoxy resin Polymers 0.000 description 3
- 230000000704 physical effect Effects 0.000 description 3
- 229920002635 polyurethane Polymers 0.000 description 3
- 239000004814 polyurethane Substances 0.000 description 3
- 241000872198 Serjania polyphylla Species 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- 239000003431 cross linking reagent Substances 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 229910003460 diamond Inorganic materials 0.000 description 2
- 239000010432 diamond Substances 0.000 description 2
- 235000014113 dietary fatty acids Nutrition 0.000 description 2
- 238000010894 electron beam technology Methods 0.000 description 2
- 239000000194 fatty acid Substances 0.000 description 2
- 229930195729 fatty acid Natural products 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 239000000049 pigment Substances 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229920002803 thermoplastic polyurethane Polymers 0.000 description 2
- QMMJWQMCMRUYTG-UHFFFAOYSA-N 1,2,4,5-tetrachloro-3-(trifluoromethyl)benzene Chemical compound FC(F)(F)C1=C(Cl)C(Cl)=CC(Cl)=C1Cl QMMJWQMCMRUYTG-UHFFFAOYSA-N 0.000 description 1
- 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
- TWJNQYPJQDRXPH-UHFFFAOYSA-N 2-cyanobenzohydrazide Chemical compound NNC(=O)C1=CC=CC=C1C#N TWJNQYPJQDRXPH-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 235000021360 Myristic acid Nutrition 0.000 description 1
- TUNFSRHWOTWDNC-UHFFFAOYSA-N Myristic acid Natural products CCCCCCCCCCCCCC(O)=O TUNFSRHWOTWDNC-UHFFFAOYSA-N 0.000 description 1
- QORUGOXNWQUALA-UHFFFAOYSA-N N=C=O.N=C=O.N=C=O.C1=CC=C(C(C2=CC=CC=C2)C2=CC=CC=C2)C=C1 Chemical compound N=C=O.N=C=O.N=C=O.C1=CC=C(C(C2=CC=CC=C2)C2=CC=CC=C2)C=C1 QORUGOXNWQUALA-UHFFFAOYSA-N 0.000 description 1
- 229920000538 Poly[(phenyl isocyanate)-co-formaldehyde] Polymers 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- 229910052770 Uranium Inorganic materials 0.000 description 1
- 229920002433 Vinyl chloride-vinyl acetate copolymer Polymers 0.000 description 1
- 239000003082 abrasive agent Substances 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 239000002216 antistatic agent Substances 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 150000001721 carbon Chemical class 0.000 description 1
- 239000012461 cellulose resin Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 239000008199 coating composition Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000003851 corona treatment Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- KIQKWYUGPPFMBV-UHFFFAOYSA-N diisocyanatomethane Chemical compound O=C=NCN=C=O KIQKWYUGPPFMBV-UHFFFAOYSA-N 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 229910052571 earthenware Inorganic materials 0.000 description 1
- 229910001651 emery Inorganic materials 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000002223 garnet Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 1
- 150000002513 isocyanates Chemical class 0.000 description 1
- 238000004898 kneading Methods 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
- 239000000314 lubricant Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- CWQXQMHSOZUFJS-UHFFFAOYSA-N molybdenum disulfide Chemical compound S=[Mo]=S CWQXQMHSOZUFJS-UHFFFAOYSA-N 0.000 description 1
- 229910052982 molybdenum disulfide Inorganic materials 0.000 description 1
- RQFLGKYCYMMRMC-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O.CCCCCCCCCCCCCCCCCC(O)=O RQFLGKYCYMMRMC-UHFFFAOYSA-N 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920005862 polyol Polymers 0.000 description 1
- 150000003077 polyols Chemical class 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 229910052573 porcelain Inorganic materials 0.000 description 1
- 238000007788 roughening Methods 0.000 description 1
- 102220013969 rs397516851 Human genes 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- 229920002545 silicone oil Polymers 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 229920005992 thermoplastic resin Polymers 0.000 description 1
- 229920001187 thermosetting polymer Polymers 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
- ITRNXVSDJBHYNJ-UHFFFAOYSA-N tungsten disulfide Chemical compound S=[W]=S ITRNXVSDJBHYNJ-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Paints Or Removers (AREA)
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
イ、産業上の利用分野
本発明は磁気テープ、磁気シート、磁気ディスク等の磁
気記録媒体に関するものである。DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to magnetic recording media such as magnetic tapes, magnetic sheets, and magnetic disks.
口、従来技術
一般に、磁気テープ等の磁気記録媒体は、磁性粉、バイ
ンダー樹脂等からなる磁性塗料を支持体上に塗布、乾燥
することによって製造される。BACKGROUND OF THE INVENTION Generally, magnetic recording media such as magnetic tapes are manufactured by applying a magnetic paint made of magnetic powder, binder resin, etc. onto a support and drying it.
こうした磁気記録媒体、特にビデオテープにおいては、
例えばＢＥＴ値が太きく （５００ｔｒｉ ／ ｇ以
上）、かつ吸油量の大きいカーボンブラックを磁性層中
に添加し、導電性を高くし、表面比抵抗を小さくしてい
た（特公昭５７−１７２９０号）。In these magnetic recording media, especially video tapes,
For example, carbon black with a large BET value (500 tri/g or more) and large oil absorption was added to the magnetic layer to increase conductivity and reduce surface resistivity (Japanese Patent Publication No. 57-17290). .
また、磁気テープの走行耐久性、磁性層の耐摩耗性を高
めるために、粒径５０ｍμ以上の比較的大粒径のカーボ
ンブラックが磁性層に混入されていた（特公昭５２−１
８５６１号、特公昭５３−３３２４９号、特公昭５７−
１２２０８号）。In addition, in order to improve the running durability of the magnetic tape and the abrasion resistance of the magnetic layer, relatively large carbon black with a particle size of 50 mμ or more was mixed into the magnetic layer (Japanese Patent Publication No. 52-1
No. 8561, Special Publication No. 53-33249, Special Publication No. 57-
No. 12208).
しかしながら、いずれの技術においても、磁性層の摩擦
係数が高く、磁性塗料の粘度が高くなりやすくて塗布性
が悪く、電磁変換特性が低下し、光の遮光性が悪い。However, in either technique, the coefficient of friction of the magnetic layer is high, the viscosity of the magnetic paint tends to increase, resulting in poor coating properties, poor electromagnetic conversion properties, and poor light blocking properties.
媒体の導電性、摩擦係数、表面性（即ち、電磁変換特性
）、耐摩耗性等といった特性のうち、いくつかを同時に
満足するためにカーボンブラックを併用する技術は、従
来、特開昭５９−５４２６号、同５９−１６１４１号、
同５８−２１８０３９号、同５８−２１１３２１号、特
公昭５３−２０２０３号、同５４−９０４１号、同５７
−４９６８号等の各公報に示すものが知られている。The technique of using carbon black in combination to simultaneously satisfy some of the characteristics of a medium, such as conductivity, coefficient of friction, surface properties (i.e., electromagnetic conversion characteristics), and wear resistance, was previously disclosed in Japanese Unexamined Patent Application Publication No. 1983-1999. No. 5426, No. 59-16141,
No. 58-218039, No. 58-211321, Special Publication No. 53-20203, No. 54-9041, No. 57
Those shown in various publications such as No.-4968 are known.
しかし、表面を粗すことなく （即ち、磁気記録媒体の
電磁変換特性を落とすことなく）、導電性に優れ、かつ
摩擦係数の低い（即ち、走行性が良好で耐辛耗性に優れ
る）記録媒体を提供するには不十分であった。However, recording with excellent conductivity and low friction coefficient (i.e., good running performance and excellent wear resistance) without roughening the surface (i.e., without degrading the electromagnetic conversion characteristics of the magnetic recording medium) is possible. It was insufficient to provide the medium.
ハ８発明の目的
本発明の目的は、高い電磁変換特性を達成でき（表面粗
さＲａが大きくならない）、表面比抵抗が低く、ドロッ
プアウトが少なく、耐摩耗性が優れて走行耐久性テスト
時の出力低下が少なく、塗液の塗布スピードを増加させ
た場合でも塗布性が劣化せずに安定した電磁変換特性が
得られ、塗液の液物性（粘度、凝集）が安定しており、
更にスーパーカレンダー６ラインスピードを増加させる
場合にカレンダビリティが劣化せず、安定した電磁変換
特性が得られる媒体を提供することにある。C8 Purpose of the invention The purpose of the present invention is to achieve high electromagnetic conversion characteristics (surface roughness Ra does not increase), low surface resistivity, little dropout, and excellent wear resistance during running durability tests. There is little output drop, stable electromagnetic conversion characteristics are obtained without deterioration of coating properties even when the coating speed is increased, and the liquid physical properties (viscosity, cohesion) of the coating liquid are stable.
Furthermore, it is an object of the present invention to provide a medium in which calenderability does not deteriorate when the supercalender 6 line speed is increased and stable electromagnetic conversion characteristics can be obtained.
二６発明の構成及びその作用効果
即ち、本発明は、比表面積がＢＥＴ値で１５ｍ／ｇ以上
、５０イ／ｇ未満であり、かつ吸油量がＤＢＰ値で２０
０ ｍ Ｅ ／１００ｇ以下である第１のカーボンブラ
ックと；比表面積がＢＥＴ値で９＋）Ｏｒｄ ／ ｇ以
上であり、かつ吸油量がＤＢＰ値で２００ ｍ ｌ ／
１００ｇ以上である第２のカーボンブラックとが磁性層
に含有されている磁気記録媒体に係るものである。26 Structure and effect of the invention, that is, the present invention has a specific surface area of 15 m/g or more and less than 50 m/g in BET value, and an oil absorption of 20 m/g in DBP value.
The first carbon black has a specific surface area of 9+)Ord/g or more in BET value and an oil absorption of 200 ml/g in DBP value.
The present invention relates to a magnetic recording medium in which the magnetic layer contains 100 g or more of second carbon black.
本発明によれば、ＢＥＴ値及び吸油量を夫々特定範囲に
有する第１のカーボンブラックと第２のカーボンブラッ
クとを併用しているので、従来技術についての既述した
欠陥が十分に解消されることが判明したのである。According to the present invention, since the first carbon black and the second carbon black, each having a BET value and an oil absorption amount within a specific range, are used together, the above-mentioned defects of the prior art can be sufficiently eliminated. It turned out that.
本発明に使用する第１のカーボンブラック及び第２のカ
ーボンブラックは、磁性層に添加する量がｍＷ （磁性
体１００部に対して２部以下）であっても、その効果を
発揮する点に特長がある。本来、磁性層中には、磁気記
録と関係のないフィラーは出来る限りその量を減らした
い。本カーボンはその目的にかなっており、したがって
レベルの高い電磁変換特性が達成できる。第１のカーボ
ンブラックは微量添加により、磁性層の動摩擦係数を低
くする事ができる。The first carbon black and the second carbon black used in the present invention exhibit their effects even if the amount added to the magnetic layer is mW (2 parts or less per 100 parts of the magnetic material). It has its features. Originally, it is desirable to reduce the amount of filler unrelated to magnetic recording in the magnetic layer as much as possible. This carbon is fit for purpose and therefore achieves a high level of electromagnetic conversion properties. By adding a small amount of the first carbon black, it is possible to lower the dynamic friction coefficient of the magnetic layer.
更に驚くべき事は、通常、１ｌｆｆｉ添加で効果のある
カーボン（例えば特公昭５３−３３２４９号のＨ３−５
００： Ｂ Ｅ Ｔ３７ ｒｌ ／ ｇ未満、吸油Ｗｋ
４４１ｍ Ｉ！ ／１００ｇ以上）は電磁変換特性を劣
化させるのが常であったが、本発明に使用する第１のカ
ーボンブラックはＨ３−５００等のカーボンと同量添加
しても、電磁変換特性の劣化は少ない。この違いは、吸
油量の違いが原因となっていると考えられる。What is more surprising is that carbon that is usually effective with the addition of 1lffi (for example, H3-5 of Japanese Patent Publication No. 53-33249)
00: Less than BET37 rl/g, oil absorption Wk
441m I! /100g or more) used to deteriorate the electromagnetic conversion characteristics, but even if the first carbon black used in the present invention is added in the same amount as carbon such as H3-500, the electromagnetic conversion characteristics do not deteriorate. few. This difference is thought to be caused by a difference in oil absorption.
、：れまでは、カーボンの吸油量を特定せずに単にカー
ボンの平均粒子径だけを指定してきたが、それらのカー
ボンを使用したテープは低い電磁変換特性に甘んじてい
た。さて、第１のカーボンブラックは特定のＢＥＴ値及
びＤＢＰ値のため、微量添加で摩擦係数が低減できるた
め、媒体の走行安定性が確立できる。そして、耐摩耗性
に優れ、走行耐久性テストでの出力低下が少ないという
効゛果がある。Until now, only the average particle size of carbon was specified without specifying the oil absorption amount of carbon, but tapes using these carbons were content with poor electromagnetic conversion characteristics. Now, since the first carbon black has a specific BET value and DBP value, the friction coefficient can be reduced by adding a small amount, so that running stability of the medium can be established. It also has the effect of having excellent abrasion resistance and less loss of output in running durability tests.
しかし、第１のカーボンブラックは単独で使用した場合
、磁性層の表面比抵抗が若干高くなる。However, when the first carbon black is used alone, the surface resistivity of the magnetic layer becomes slightly higher.
そこで、本発明によれば、ＢＥＴ９００ ｒｒｒ／ｇ以
上でかつ吸油量２００ ｍ Ｉ！／１００ｇ以上の第２
のカーボンブラックを併用する事で、表面比抵抗を下げ
る事ができる。この第２のカーボンブラックも、磁性体
１００重量部に対して５部以下で有効に作用する。Therefore, according to the present invention, the BET is 900 rrr/g or more and the oil absorption is 200 m I! /100g or more second
By using carbon black in combination, the surface resistivity can be lowered. This second carbon black also acts effectively in amounts of 5 parts or less per 100 parts by weight of the magnetic material.
また、上記の第１及び第２の両力−ボンブラックを使用
した場合、驚くべき事が発見された。即ち、両力−ボン
を使用した磁性塗液は、粘度安定性、凝集が起こりにく
い等、液物性の安定性において優れているのみならず、
塗布速度を増加させた場合、塗布性が劣化せず、高い電
磁変換特性が維持できた。In addition, when using the first and second dual-bonk blacks described above, a surprising thing was discovered. In other words, the magnetic coating liquid using Ryoryoku-bon not only has excellent stability of liquid physical properties such as viscosity stability and difficulty in agglomeration, but also
When the coating speed was increased, the coating properties did not deteriorate and high electromagnetic conversion characteristics were maintained.
なお、上記においては、第１のカーボンブラックのＢＥ
Ｔ値は２０〜７０ｒｒｒ／ｇとするのがよく、また、第
２のカーボンブラックのＢＥＴ値は１１００ｍ２／ｇ以
上、２０００ｒｒｒ／ｇ以下とするのがよい。吸油量に
ついては、第１のカーボンブラックは１１０〜２００
ｍ Ｉ！ ／１００ｇ、更には１８０〜２００ ｍ ４
２ ／１００ｇがよく、第２のカーボンブラ、りは２２
０ｍ ７！／１００ｇ以上、４００ ｍ Ｉ！ ／ １
００ｇ以下が好ましい。In addition, in the above, BE of the first carbon black
The T value is preferably 20 to 70 rrr/g, and the BET value of the second carbon black is preferably 1100 m2/g or more and 2000 rrr/g or less. Regarding oil absorption, the first carbon black has an oil absorption of 110 to 200.
m I! /100g, even 180-200 m4
2/100g is good, second carbon bra, 22
0m 7! /100g or more, 400m I! / 1
00g or less is preferable.
本発明において、上記の効果を得る上で、力一ポンプラ
ックの添加量については、第１及び第２のカーボンブラ
ックとも夫々、磁性粉１００重景重量対して５重量部以
下、更には３重量部以下がよく、２重量部以下がもっと
よい。In the present invention, in order to obtain the above effects, the amount of addition of the first and second carbon blacks should be 5 parts by weight or less, more preferably 3 parts by weight, based on the weight of 100 pieces of magnetic powder. Parts by weight or less is better, and 2 parts by weight or less is even better.
また、両力−ボンブラックの比率にも望ましい範囲があ
り、重量比で第１のカーボンブラック：第２のカーボン
ブラック＝ （１０： ９０）〜（９０： １０）がよ
（、（３０： ７０）〜（７０： ３０）が更によく、
（４０： ６０）〜（６０： ４０）がもっとよい。In addition, there is a desirable range for the ratio of both forces and carbon black, and the weight ratio of first carbon black to second carbon black = (10: 90) to (90: 10), (30: 70). ) ~ (70: 30) is even better,
(40:60)~(60:40) is better.
本発明で使用可能な第１のカーボンブラックとしては、
例えば電気化学工業社製Ｈ３−１００（ＢＥＴ３２ｒｒ
ｒ／ ｇ 、 Ｄ Ｂ Ｐ１８０ｍ ｌ／１００ｇ１粒
径５３ｍμ）、三菱化成社製の９３５００ （Ｂ Ｅ
Ｔ４７Ｍ／ｇ、ＤＢＰ１８７ ｍ ／ ／１００ｇ、粒
径４０ｒｎｃｒ）等が挙げられる。The first carbon black that can be used in the present invention includes:
For example, Denki Kagaku Kogyo H3-100 (BET32rr
r/g, D B P180 ml/100 g 1 particle size 53 mμ), 93500 manufactured by Mitsubishi Chemical Corporation (B E
T47M/g, DBP187 m//100g, particle size 40rncr), etc.
第２のカーボンブラックとしては、キャボット社製のブ
ラック・パールズー２０００ （Ｂ Ｅ Ｔ１４７５ｍ
２／ ｇ、Ｄ Ｂ Ｐ３３０ ｍ ｌ ／１００ｇ、粒
径１５ｍμ） 、コロンビアンカーボン社製のコンダク
テソクス４０−２２０（Ｂ Ｅ ７１０６６ｍ／ ｇ
、 Ｄ Ｂ Ｐ２Ｓ５ ｍ ｌ ／１００ｇ）等が挙げ
られる。As the second carbon black, Black Pearl Zoo 2000 (BE T1475m manufactured by Cabot) was used.
2/g, D B P330 ml/100 g, particle size 15 mμ), Conductexox 40-220 manufactured by Columbia Carbon (BE 71066 m/g)
, DB P2S5 ml/100g).
なお、上記において、「比表面積」とは、単位重量あた
りの表面積をいい、平均粒子径とは全く異なった物理量
であり、例えば平均粒子径は同一であっても、比表面積
が大きなものと、比表面積が小さいものが存在する。比
表面積の測定は、例えばまず、磁性粉末を２５０℃前後
で３０〜６０分加熱処理しながら脱気して、該粉末に吸
着されているものを除去し、その後、測定装置に導入し
て、窒素の初期圧力を０．５ｋｇ／ｒｄに設定し、窒素
により液体窒素温度（−１９５℃）で吸着測定を行なう
（一般にＢ、Ｅ、Ｔ法と称されている比表面積の測定方
法。詳しくはＪ、Ａｍｅ、Ｃｈｅｍ、Ｓｏｃ、 ６０３
０９（１９３８）を参照）。この比表面積（ＢＥＴ値）
の測定装置には、湯銭電池側ならびに湯銭アイオニクス
■の共同製造による「粉粒体測定装置（カンタ−ソープ
）」を使用することができる。比表面積ならびにその測
定方法についての一般的な説明は「粉体の測定」（ｊ、
Ｍ、ＤＡＬＬＡＶＡＬＬＥ、ＣＬＹＤＥＯＲＲＪｒ共著
、弁口その他訳；産業図書社刊）に詳しく述べられてお
り、また「化学便覧」 （応用編、１１７０〜１１７１
頁、日本化学会編、丸首■昭和４１年４月３０日発行）
にも記載されている（なお前記「化学便覧」では、比表
面積を単に表面積（ｒｒｒ／ｇｒ）と記載しているが、
本明細書における比表面積と同一のものであるう）。In addition, in the above, "specific surface area" refers to the surface area per unit weight, and is a physical quantity completely different from the average particle size. For example, even if the average particle size is the same, the specific surface area is large, Some have small specific surface areas. To measure the specific surface area, for example, first, the magnetic powder is heated at around 250 ° C. for 30 to 60 minutes while being degassed to remove what is adsorbed to the powder, and then introduced into a measuring device. The initial pressure of nitrogen is set to 0.5 kg/rd, and the adsorption measurement is performed using nitrogen at liquid nitrogen temperature (-195°C) (Specific surface area measurement method generally referred to as B, E, T method. J, Ame, Chem, Soc, 603
09 (1938)). This specific surface area (BET value)
As the measuring device, it is possible to use the "powder measuring device (Cantersoap)" jointly manufactured by Yusen Batteries and Yusen Ionics (2). A general explanation of the specific surface area and its measurement method can be found in “Powder Measurement” (j,
Co-authored by M. DALLAVALLE, CLYDEORR Jr., Translated by Benguchi and others; Published by Sangyo Toshosha).
Page, edited by the Chemical Society of Japan, round neck ■ Published April 30, 1966)
(Note that in the above-mentioned "Chemistry Handbook", the specific surface area is simply described as surface area (rrr/gr),
This is the same as the specific surface area in this specification).
また、上記の「吸油１（ＤＢＰ法）」については、顔料
粉末１００ｇにＤ Ｂ Ｐ （Ｄｉｂｕｔｙｌ ｐｈｔ
ｈａｌａｔｅ）を少しずつ加え、練り合わせながら顔料
の状態を観察し、ばらばらに分散した状態から一つの塊
をなす点を見出したときのＤＢＰのｍａ数をＤＢＰ吸油
量とする。In addition, for the above-mentioned "Oil absorption 1 (DBP method)", 100g of pigment powder is mixed with D B P (Dibutyl pht method).
halate) little by little, observe the condition of the pigment while kneading it, and determine the ma number of DBP when it is found that it forms a single lump from a dispersed state as the DBP oil absorption amount.
本発明の磁気記録媒体は、例えば第１図に示すように、
支持体１上に磁性層２を有している。また磁性層２とは
反対側の面にＢＣＣ２０設けられている。このＢＣｊｉ
Ｊは設けられてよいが、設けなくてもよい。磁性層２に
使用される磁性粉末、特に強磁性粉末としては、γ−Ｆ
ｅｚＯ，，、Ｇｏ含有Ｔ ＦｅｚＯ，、、ＦｅｚＯａ
、Ｃｏ含有Ｆｅ１ｇ４等の磁性粉が挙げられる。これ
らのうち、Ｃｏ含有酸化鉄が望ましい。また、磁性粉の
ＢＥＴ値は３５ｍ２／ｇ以上、更には４０ｍ／ｇ以上の
場合は効果が著しい。磁性Ｎ２には、上述した第１及び
第２のカーボンブラックの他、潤滑剤（例えばシリコー
ンオイル、グラファイト、二硫化モリブデン、二硫化タ
ングステン、炭素原子数１２〜２０の一塩基性脂肪酸（
例えばステアリン酸）と炭素原子数が３〜２６個の一価
のアルコールからなる脂肪酸エステル等）をカーボンブ
ラックに対し１０〜５０重量％添加したり、帯電防止剤
（例えばグラファイト）等を添加してよい。また、非磁
性研磨材粒子も添加してよいが、これにはアルミナ（α
−Ａ ｌ ｔ Ｏ：１（コランダム）等）、人造コラン
ダム、溶融アルミナ、炭化ケイ素、酸化クロム、ダイヤ
モンド、人造ダイヤモンド、ザクロ石、エメリー（主成
分：コランダムと磁鉄鉱）等が使用される。この研磨材
の含有量は磁性粉に対して２０重量部以下が好ましく、
またその平均粒子径は０．５μｍがよく、０．４μｍ以
下が更によい。The magnetic recording medium of the present invention has, for example, as shown in FIG.
A magnetic layer 2 is provided on a support 1. Further, a BCC 20 is provided on the surface opposite to the magnetic layer 2. This BCji
Although J may be provided, it is not necessary to provide it. The magnetic powder used for the magnetic layer 2, especially the ferromagnetic powder, is γ-F.
ezO,, Go-containing T FezO,, FezOa
, Co-containing Fe1g4, and other magnetic powders. Among these, Co-containing iron oxide is preferred. Further, the effect is remarkable when the BET value of the magnetic powder is 35 m2/g or more, more preferably 40 m/g or more. In addition to the first and second carbon blacks mentioned above, magnetic N2 also contains lubricants (such as silicone oil, graphite, molybdenum disulfide, tungsten disulfide, and monobasic fatty acids having 12 to 20 carbon atoms).
For example, 10 to 50% by weight of stearic acid (stearic acid) and a fatty acid ester consisting of a monohydric alcohol having 3 to 26 carbon atoms) may be added to carbon black, or an antistatic agent (such as graphite) may be added. good. Additionally, non-magnetic abrasive particles may also be added, including alumina (α
-Al t O: 1 (corundum), etc.), artificial corundum, fused alumina, silicon carbide, chromium oxide, diamond, artificial diamond, garnet, emery (main components: corundum and magnetite), etc. are used. The content of this abrasive material is preferably 20 parts by weight or less based on the magnetic powder,
Further, the average particle diameter is preferably 0.5 μm, and even more preferably 0.4 μm or less.
また、磁性層のバインダー樹脂として少なくともポリウ
レタンを使用できるが、これは、ポリオールとポリイソ
シアネートとの反応によって合成できる。ポリウレタン
と共に、フェノキシ樹脂及び／又は塩化ビニル系共重合
体も含有せしめれば、磁性層に適用する場合に磁性粉の
分散性が向上し、その機械的強度が増大する。但、フェ
ノキシ樹脂及び／又は塩化ビニル系共重合体のみでは層
が硬くなりすぎるがこれはポリウレタンの含有によって
防止でき、支持体又は下地層との接着性が良好となる。Furthermore, at least polyurethane can be used as the binder resin for the magnetic layer, which can be synthesized by reacting polyol and polyisocyanate. If a phenoxy resin and/or a vinyl chloride copolymer is contained together with polyurethane, the dispersibility of the magnetic powder will be improved when applied to a magnetic layer, and its mechanical strength will be increased. However, if only the phenoxy resin and/or the vinyl chloride copolymer is used, the layer becomes too hard, but this can be prevented by containing polyurethane, and the adhesion to the support or base layer is improved.
また、上記以外にも、バインダー樹脂として繊維素系樹
脂、熱可塑性樹脂、熱硬化性樹脂、反応型樹脂、電子線
照射硬化型樹脂が使用されてもよい。In addition to the above, cellulose resins, thermoplastic resins, thermosetting resins, reactive resins, and electron beam curable resins may be used as the binder resin.
また、８０層３にも、磁性層２に用いた本発明による上
記カーボンブラックを添加してよい。Further, the carbon black according to the present invention used in the magnetic layer 2 may also be added to the 80 layer 3.
また、第１図の磁気記録媒体は、磁性Ｎ２と支持体１と
の間に下引き層（図示せず）を設けたものであってよく
、或いは下引き層を設けなくてもよい（以下同様）。ま
た支持体にコロナ放電処理をほどこしてもよい。Further, the magnetic recording medium shown in FIG. 1 may be provided with an undercoat layer (not shown) between the magnetic N2 and the support 1, or may not be provided with an undercoat layer (hereinafter referred to as similar). The support may also be subjected to corona discharge treatment.
また、支持体１の素材としては、ポリエチレンテレフタ
レート、ポリプロピレン等のプラスチック、Ａ１、Ｚｎ
等の金属、ガラス、ＢＮ、Ｓｉカーバイド、磁器、陶器
等のセラミックなどが使用される。In addition, the material of the support 1 includes plastics such as polyethylene terephthalate and polypropylene, A1, and Zn.
Metals such as glass, BN, Si carbide, ceramics such as porcelain and earthenware, etc. are used.
なお、上記の磁性層等の塗布形成時には、塗料中に架橋
剤としての多官能イソシアネートを所定量添加しておく
のが磁性層を強固にできる点で望ましい。こうした架橋
剤としては、既述した多官能ポリイソシアネートの他、
トリフェニルメタントリイソシアネート、トリス−（ｐ
−イソシアネートフェニル）チオホスファイト、ポリメ
チレンポリフェニルイソシアネート等があげられる。メ
チレンジイソシアネート系、トリレンジイソシアネート
系がよい。なお、磁性層を電子線照射等で硬化させると
きは、イソシアネート化合物の添加は省略してもよいが
添加してあってもよい。In addition, when coating and forming the above-mentioned magnetic layer, etc., it is desirable to add a predetermined amount of polyfunctional isocyanate as a crosslinking agent to the coating material in order to strengthen the magnetic layer. Examples of such crosslinking agents include the polyfunctional polyisocyanates mentioned above,
Triphenylmethane triisocyanate, tris-(p
-isocyanate phenyl) thiophosphite, polymethylene polyphenylisocyanate, and the like. Methylene diisocyanate type and tolylene diisocyanate type are preferable. Note that when the magnetic layer is cured by electron beam irradiation or the like, the addition of the isocyanate compound may be omitted, but it may be added.
第２図は、他の磁気記録媒体を示すものであるが、第１
図の媒体の磁性層２上にｏｃ１４が設けられている。こ
の００層４は、磁性層２を損傷等から保護するために設
けられるが、そのために滑性が十分である必要がある。FIG. 2 shows other magnetic recording media.
An oc14 is provided on the magnetic layer 2 of the illustrated medium. This 00 layer 4 is provided to protect the magnetic layer 2 from damage, etc., and for this purpose, it needs to have sufficient slipperiness.
そこで、ｏｃ１４のバインダー樹脂として、上述の磁性
層２に使用したウレタン樹脂を（望ましくはフェノキシ
樹脂及び／又は塩化ビニル系共重合体を併用して）使用
する。００層４の表面粗さは特にカラーＳ／Ｎとの関連
でＲａ≦０．ＯＩｔ’ｍＳＲｍａＸ≦０．１３μｍとす
るのがよい。この場合、支持体１の表面粗さをＲａ≦０
．０１μｍ、 Ｒｍａｘ≦０．１３μｍとし、平滑な支
持体１を用いるのが望ましい。Therefore, as the binder resin for oc14, the urethane resin used in the magnetic layer 2 described above is used (preferably in combination with a phenoxy resin and/or a vinyl chloride copolymer). The surface roughness of the 00 layer 4 is Ra≦0, especially in relation to the color S/N. It is preferable that OIt'mSRmaX≦0.13 μm. In this case, the surface roughness of the support 1 is Ra≦0.
．． 0.1 μm, Rmax≦0.13 μm, and it is desirable to use a smooth support 1.
第３図は、磁気ディスクとして構成された磁気記録媒体
を示し、支持体１の両面に上述と同様の磁性層２．０Ｃ
Ｎ４が夫々設けられており、００層４には上述のウレタ
ン樹脂を主成分とするバインダー樹脂が含有せしめられ
てよい。FIG. 3 shows a magnetic recording medium configured as a magnetic disk, with magnetic layers 2.0C similar to those described above on both sides of the support 1.
N4 is provided respectively, and the 00 layer 4 may contain a binder resin whose main component is the above-mentioned urethane resin.
ホ、実施例 以下、本発明を具体的な実施例につき説明する。E, Example Hereinafter, the present invention will be explained with reference to specific examples.
但し、以下において「部」は重量部を表わす。However, in the following, "parts" represent parts by weight.
次の磁性塗料用の各成分を用意した。The following components for magnetic paint were prepared.
Ｃｏ含有磁性酸化鉄 １００部塩ビー
酢ビ共重合体 １３〃（Ｕ、Ｃ，Ｃ社
のＶ Ａ Ｇ Ｈ）
ポリウレタン樹脂 ７〃（グソ
ドリフチ社のニスタン５７０１）α−Ａ１２０２
５ 〃ミリスチン酸
１〃ステアリン酸ブチル
１〃レシチン ３
〃ポリイソシアネート １３〃シク
ロヘキサノン １３０〃トルエン
７０〃これらの成分をボー
ルミルで分散した磁性粉分散塗液を、ポリイソシアネー
ト添加後に厚さ１５μｍのポリエチレンテレフタレート
ベースの片面に押出しコーターにて塗布し、乾燥させ、
カレンダー表面処理をほどこした後、２インチ幅に断裁
した。Co-containing magnetic iron oxide 100 parts Vinyl chloride vinyl acetate copolymer 13 (VAGH from U, C, C) Polyurethane resin 7 (Nistan 5701 from Gusodorifuchi) α-A1202
5 Myristic acid
1〃Butyl stearate
1〃Lecithin 3
〃Polyisocyanate 13〃Cyclohexanone 130〃Toluene
70〃A magnetic powder dispersion coating liquid prepared by dispersing these components using a ball mill is applied to one side of a 15 μm thick polyethylene terephthalate base using an extrusion coater after adding polyisocyanate, and dried.
After applying a calender surface treatment, it was cut into a 2-inch width.
この時、磁性層の膜厚は平均４．０μであった。At this time, the average thickness of the magnetic layer was 4.0 μm.
各ビデオテープについては次の測定を行なったところ、
第４図に示す結果が得られた。The following measurements were made for each videotape:
The results shown in FIG. 4 were obtained.
ＲＦ出カニＲＦ高出測定用ＶＴＲデツキを用いて４ＭＨ
ｚでのＲＦ高出を測定し、１００回再生後の、当初の出
力に対して低
下している値を示した（単位：ｄＢ）
ルミＳ／Ｎ：測定器はシバツク社製ノイズメーター（９
２５Ｄ／１）を使用し、試料隘３を基準テープ（ＯｄＢ
）とし、
それに対する差で表示した。バイ
パスフィルターは４．２ＭＨｚ、ロー
パスフィルターは１０ＫＨｚで行った。4MH using a VTR deck for measuring RF output
We measured the high RF output at
25D/1) and set the sample hole 3 to the reference tape (OdB
) and expressed as the difference. The bypass filter was set to 4.2 MHz, and the low pass filter was set to 10 KHz.
ＶＴＲはＪＶＣＨＲ−Ｄ１２０を使 用した。I use JVCHR-D120 as a VTR. used.
摩擦係数：ヘッドシリンダーの入口、出口に於けるテー
プテンションを測定して
表面比抵抗：表面電位計で測定。Friction coefficient: Measure the tape tension at the inlet and outlet of the head cylinder. Surface specific resistance: Measure with a surface electrometer.
ドロップアウト：再生画面上でのキズの発生個数。Dropout: Number of scratches that occur on the playback screen.
第４図の結果から、本発明に基いて２種のカーボンブラ
ックを併用した場合（試料陽３．８）、比較例に比べて
次の点で優れていることが分る。From the results shown in FIG. 4, it can be seen that when two types of carbon black are used together according to the present invention (sample positive 3.8), it is superior to the comparative example in the following points.
（１）高い電磁変換特性を達成できる（表面粗さＲａが
大きくならない）。(1) High electromagnetic conversion characteristics can be achieved (surface roughness Ra does not increase).
（２）表面比抵抗が低く、ドロップアウトが少ない。(2) Low surface resistivity and little dropout.
（３）耐摩耗性が優れ、走行耐久性テスト時の出力低下
が少ない。(3) Excellent wear resistance, with little output drop during running durability tests.
（４）塗液の塗布スピードを増加させた場合、塗布性が
劣化せず、安定した電磁変換特性が得られる。(4) When the coating speed of the coating liquid is increased, the coating properties do not deteriorate and stable electromagnetic conversion characteristics can be obtained.
（５）スーパーカレンダーのライン・スピードを増加さ
せる場合、カレンダビリティが劣化せず、安定した電磁
変換特性が得られる。(5) When the line speed of the supercalender is increased, the calenderability does not deteriorate and stable electromagnetic conversion characteristics can be obtained.
（６）塗液の液物性（粘度、凝集）が安定している。(6) The liquid physical properties (viscosity, cohesion) of the coating liquid are stable.
次に、上記の試料！ｌｈ３に準じて試料を作成する際、
カーボンブラックの各物理量との関係で測定した結果を
第５図〜第８図に示した。Next, the sample above! When preparing a sample according to lh3,
The results measured in relation to each physical quantity of carbon black are shown in FIGS. 5 to 8.
第５図：第１のカーボンブラック（Ｈ３−１００）を固
定して、第２のカーボンブラックのＢＥＴ値に応じたル
ミＳ／Ｎを示した。FIG. 5: The first carbon black (H3-100) was fixed, and the Lumi S/N was shown according to the BET value of the second carbon black.
第６図：第１のカーボンブラック（Ｈ５−１００）を固
定して、第２のカーボンブラックのＤＢＰ吸油量に応じ
た表面比抵抗を示した。FIG. 6: The first carbon black (H5-100) was fixed, and the surface specific resistance of the second carbon black was shown depending on the DBP oil absorption amount.
第７図：第２のカーボンブラック（Ｂ Ｐ ２０００）
を固定して、第１のカーボンブラックの
ＢＥＴ値に応じた動摩擦係数を示した。Figure 7: Second carbon black (B P 2000)
is fixed, and the dynamic friction coefficient is shown according to the BET value of the first carbon black.
第８図：第２のカーボンブラック（Ｂ Ｐ ２０００）
を固定して、第１のカーボンブラックの
ＤＢＰ吸油量に応じたルミＳ／Ｎを示した。Figure 8: Second carbon black (B P 2000)
is fixed, and the Lumi S/N is shown according to the DBP oil absorption amount of the first carbon black.
以上より、第１のカーボンブラックのＢＥＴ値を１５ｎ
ｆ／ｇ以上、５０ｒｒｒ／ｇ未満にしないと低摩擦が得
られず、またその吸油量も２００ ｍ ｌ ／ １００
ｇ以下でＳ／Ｎが著しく向上すること、更に第２の力
゛−ボンブラックのＢＥＴ値を９００ｍ２／ｇ以上と
すればルミＳ／Ｎを向上させ、またその吸油量も１１０
ｍ ｌ ／１００ｇ以上とすることによって表面比抵抗
を低下させることができる。このように、本発明の範囲
に限定することの優位性が顕著であることが分る。From the above, the BET value of the first carbon black is 15n
f/g or more and less than 50 rrr/g, low friction cannot be obtained, and the oil absorption amount is also 200 ml / 100
g or less, the S/N is significantly improved, and the second force
-If the BET value of the bomb black is set to 900 m2/g or more, the Lumi S/N will improve, and its oil absorption will also increase to 110 m2/g.
By setting m l /100g or more, the surface specific resistance can be lowered. Thus, it can be seen that the advantage of limiting the scope of the present invention is remarkable.
図面は本発明の実施例を示すものであって、第１図、第
２図、第３図は各側による磁気記録媒体の一部分の各拡
大断面図、
第４図は各側によるテープの磁性塗料組成をまとめて示
す表、
第５図、第６図、第７図、第８図はカーボンブラックの
物理量を変化させたときの各特性を示すグラフ
である。
なお、図面に用いられている符号において、２−・−・
−・−・磁性層
３−−−−−−−・−・・・−・バックコート層（ＢＣ
層）である。
代理人 弁理士 逢 坂 宏
第１図
第２図
第３図
第６図The drawings show an embodiment of the present invention, in which FIGS. 1, 2, and 3 are enlarged cross-sectional views of a portion of a magnetic recording medium on each side, and FIG. 4 shows magnetic properties of a tape on each side. A table summarizing the coating composition, and FIGS. 5, 6, 7, and 8 are graphs showing each characteristic when the physical quantity of carbon black is changed. In addition, in the symbols used in the drawings, 2-・-・
---・Magnetic layer 3-----・Back coat layer (BC
layer). Agent Patent Attorney Hiroshi AisakaFigure 1Figure 2Figure 3Figure 6
Claims (1)
＾２／ｇ未満であり、かつ吸油量がＤＢＰ値で２００ｍ
ｌ／１００以下である第１のカーボンブラックと；比表
面積がＢＥＴ値で９００ｍ＾２／ｇ以上であり、かつ吸
油量がＤＢＰ値で２００ｍｌ／１００ｇ以上である第２
のカーボンブラックとが磁性層に含有されている磁気記
録媒体。1. Specific surface area is 15m^2/g or more in BET value, 50m
less than ^2/g, and the oil absorption amount is 200m in DBP value.
A first carbon black whose specific surface area is 900 m^2/g or more in BET value and a second carbon black whose oil absorption is 200 ml/100 g or more in DBP value.
A magnetic recording medium in which a magnetic layer contains carbon black.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19968386A JPH0746420B2 (en) | 1986-08-25 | 1986-08-25 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19968386A JPH0746420B2 (en) | 1986-08-25 | 1986-08-25 | Magnetic recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6355727A true JPS6355727A (en) | 1988-03-10 |
| JPH0746420B2 JPH0746420B2 (en) | 1995-05-17 |
Family
ID=16411873
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19968386A Expired - Fee Related JPH0746420B2 (en) | 1986-08-25 | 1986-08-25 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0746420B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01248317A (en) * | 1988-03-29 | 1989-10-03 | Toyobo Co Ltd | Magnetic recording medium |
| JPH0235625A (en) * | 1988-07-26 | 1990-02-06 | Konica Corp | Magnetic recoding medium |
| JP2007151337A (en) * | 2005-11-29 | 2007-06-14 | Chugoku Electric Power Co Inc:The | Cable holding tool |
-
1986
- 1986-08-25 JP JP19968386A patent/JPH0746420B2/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01248317A (en) * | 1988-03-29 | 1989-10-03 | Toyobo Co Ltd | Magnetic recording medium |
| JPH0235625A (en) * | 1988-07-26 | 1990-02-06 | Konica Corp | Magnetic recoding medium |
| JP2007151337A (en) * | 2005-11-29 | 2007-06-14 | Chugoku Electric Power Co Inc:The | Cable holding tool |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0746420B2 (en) | 1995-05-17 |
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