JPH0289221A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPH0289221A JPH0289221A JP24050388A JP24050388A JPH0289221A JP H0289221 A JPH0289221 A JP H0289221A JP 24050388 A JP24050388 A JP 24050388A JP 24050388 A JP24050388 A JP 24050388A JP H0289221 A JPH0289221 A JP H0289221A
- Authority
- JP
- Japan
- Prior art keywords
- compd
- oxazoline
- ratio
- recording medium
- magnetic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 125000003504 2-oxazolinyl group Chemical group O1C(=NCC1)* 0.000 claims abstract description 3
- 239000004593 Epoxy Substances 0.000 claims abstract 3
- 150000001875 compounds Chemical class 0.000 claims description 11
- -1 oxazoline compound Chemical class 0.000 claims description 5
- 239000003973 paint Substances 0.000 claims description 5
- 239000011230 binding agent Substances 0.000 abstract description 14
- 239000003431 cross linking reagent Substances 0.000 abstract description 10
- IMSODMZESSGVBE-UHFFFAOYSA-N 2-Oxazoline Chemical compound C1CN=CO1 IMSODMZESSGVBE-UHFFFAOYSA-N 0.000 abstract description 7
- 238000006243 chemical reaction Methods 0.000 abstract description 7
- 239000011248 coating agent Substances 0.000 abstract description 5
- 238000000576 coating method Methods 0.000 abstract description 5
- 238000013329 compounding Methods 0.000 abstract 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 18
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 9
- 238000004132 cross linking Methods 0.000 description 5
- 239000006247 magnetic powder Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- ZJCCRDAZUWHFQH-UHFFFAOYSA-N Trimethylolpropane Chemical compound CCC(CO)(CO)CO ZJCCRDAZUWHFQH-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 229920001228 polyisocyanate Polymers 0.000 description 3
- 239000005056 polyisocyanate Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 239000000654 additive Substances 0.000 description 2
- WNLRTRBMVRJNCN-UHFFFAOYSA-N adipic acid Chemical compound OC(=O)CCCCC(O)=O WNLRTRBMVRJNCN-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 150000002918 oxazolines Chemical class 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229920006267 polyester film Polymers 0.000 description 2
- 229920005749 polyurethane resin Polymers 0.000 description 2
- VBICKXHEKHSIBG-UHFFFAOYSA-N 1-monostearoylglycerol Chemical compound CCCCCCCCCCCCCCCCCC(=O)OCC(O)CO VBICKXHEKHSIBG-UHFFFAOYSA-N 0.000 description 1
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 description 1
- 239000004925 Acrylic resin Substances 0.000 description 1
- 229920000178 Acrylic resin Polymers 0.000 description 1
- DCXXMTOCNZCJGO-UHFFFAOYSA-N Glycerol trioctadecanoate Natural products CCCCCCCCCCCCCCCCCC(=O)OCC(OC(=O)CCCCCCCCCCCCCCCCC)COC(=O)CCCCCCCCCCCCCCCCC DCXXMTOCNZCJGO-UHFFFAOYSA-N 0.000 description 1
- 239000000020 Nitrocellulose Substances 0.000 description 1
- 239000007983 Tris buffer Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 235000011037 adipic acid Nutrition 0.000 description 1
- 239000001361 adipic acid Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 150000008064 anhydrides Chemical class 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 125000004177 diethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- ZFSLODLOARCGLH-UHFFFAOYSA-N isocyanuric acid Chemical compound OC1=NC(O)=NC(O)=N1 ZFSLODLOARCGLH-UHFFFAOYSA-N 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- VYKXQOYUCMREIS-UHFFFAOYSA-N methylhexahydrophthalic anhydride Chemical compound C1CCCC2C(=O)OC(=O)C21C VYKXQOYUCMREIS-UHFFFAOYSA-N 0.000 description 1
- 229920001220 nitrocellulos Polymers 0.000 description 1
- 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 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229920002037 poly(vinyl butyral) polymer Polymers 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 239000004848 polyfunctional curative Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
Landscapes
- Paints Or Removers (AREA)
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は磁気記録媒体に係わり、さらに詳しくは結合剤
用架橋剤の改良に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to magnetic recording media, and more particularly to improvements in crosslinking agents for binders.
ボリヱステルフイルムなどの非磁性支持体上に結合剤中
に磁性粉末を分散、結着させてなる磁性層を設けた構造
の磁気記録媒体は、上記結合剤の種類によって、磁気記
録媒体としての賦磁変蝕特性と、繰プ返し走行安定性や
接着強度などに代表される物理０注が左右される。A magnetic recording medium has a structure in which a magnetic layer is formed by dispersing and bonding magnetic powder in a binder on a non-magnetic support such as polyester film. It is influenced by magnetization and corrosion characteristics, as well as physical characteristics such as repeated running stability and adhesive strength.
このことから、磁性ノーの耐久性に好結果を与える目的
で、結合剤の硬化剤としての働きをする添加書が禎々提
案されている。代表例としてポリイソシアネート化合物
がある。しかし、ポリイソシアネート化合物を用いた場
合、架橋反応が十分でなく、耐久性の面で４があった。For this reason, additives have been proposed that act as hardeners for binders in order to improve the durability of magnetic materials. A typical example is a polyisocyanate compound. However, when a polyisocyanate compound was used, the crosslinking reaction was not sufficient, resulting in a score of 4 in terms of durability.
これはポリインシアネート架橋剤が空気中の水分とも反
応しｆすいため、結合剤の・架橋反応にのみ利用されな
く。This is because polyincyanate crosslinking agents tend to react with moisture in the air, so they are not used only for crosslinking reactions of binders.
結合剤の硬化が十分に進まなく、磁気記録媒体の耐久性
が不十分で、性能にばらつきが生ずる原因となる。The curing of the binder does not proceed sufficiently, resulting in insufficient durability of the magnetic recording medium and variations in performance.
このポリイソシアネート化合物に代りポリグリシジル化
合物を用いる提案もある（特開昭６１−１１０３３４号
）。この杓は磁性粉の分散と磁気記録媒体の耐久性金改
舒する目的で用いられるが。There is also a proposal to use a polyglycidyl compound instead of this polyisocyanate compound (Japanese Patent Laid-Open No. 110334/1982). This ladle is used for the purpose of dispersing magnetic powder and improving the durability of magnetic recording media.
架橋反応後の磁気記録媒体の機械強度が十分でないため
、耐久性が満足するものとならなかった。Since the mechanical strength of the magnetic recording medium after the crosslinking reaction was insufficient, the durability was not satisfactory.
この発明は、上記従来製品が持っていた結合剤の架ｍ反
応が不十分であるという欠点を解決し。This invention solves the drawback of the above-mentioned conventional products that the crosslinking reaction of the binder is insufficient.
以って耐久性に優れた磁気記録媒体を提供することを目
的とする。Therefore, it is an object of the present invention to provide a magnetic recording medium with excellent durability.
本発明では、結合剤の架橋剤として、ポリグリシジル化
合物とともに、オキサゾリン化合物を用いて、磁性塗膜
の機械強度ｔ−強くすることが可能となり九。これによ
ｐ耐久性が非常に優れた磁気記録媒体を得ることができ
る。In the present invention, by using an oxazoline compound together with a polyglycidyl compound as a crosslinking agent for the binder, it is possible to increase the mechanical strength of the magnetic coating film. As a result, a magnetic recording medium with extremely excellent p durability can be obtained.
本発明で用いるポリグリシジル化合物としては。The polyglycidyl compound used in the present invention includes:
トリメチロールプロパンポリグリシジルエーテル。Trimethylolpropane polyglycidyl ether.
ペンタエリストールポリグリ７ジルエーテル トリグリ
シジルトリス（２−ヒドロ中ジエチル）イソシアヌレー
ト、グリセロールポリグリシジルエーテルなどが挙げら
れる。Examples include pentaerythol polyglycidyl ether, triglycidyl tris(diethyl in 2-hydro)isocyanurate, and glycerol polyglycidyl ether.
また、オキサゾリン化合物としては
オキサゾリン）
２．２−（ナト２メチレン）ビス（２−オキサゾリン）
などが挙げられ、オキナシリンｊｌｔ’２個以上含んで
いる化合物であればよｉｏ
このポリグリシジル化合物とオキサゾリン化合物の配合
比はエボ中７環とオキサゾリン環の数の比が０．５〜５
：１の範囲にあるのが好ましい。エポ中Ｓ／環の数がこ
の比よりも大きすぎても、小さすぎても塗膜の強度が弱
くなる。このｉＪａ数比が２＝１前後の配合比を用いた
場合、塗膜強度が強くなり、特に好ましい配合比となる
。In addition, examples of the oxazoline compound include oxazoline) 2,2-(nato-2-methylene)bis(2-oxazoline), and any compound containing two or more oxazoline compounds is acceptable. The blending ratio of 7 rings in Evo and the number of oxazoline rings is 0.5 to 5.
: It is preferable that it is in the range of 1. If the number of S/rings in the epoxy resin is too large or too small than this ratio, the strength of the coating film will be weakened. When a blending ratio in which the iJa number ratio is around 2=1 is used, the strength of the coating film becomes strong, resulting in a particularly preferable blending ratio.
上記配合組成の架橋剤の使用量は結合剤２５０ＩＥｔ１
１ＳＫ対して０．５〜３０１ｉ（ｆｉ部用いるのが好ま
しい。また架橋反応を促進するためには触媒として、メ
チルへキサヒドロ無水フタル酸などの＃ｌ無水物ｆアジ
ピン酸などの二塩基酸などを用いることも５ｂる。The amount of crosslinking agent used in the above formulation is 250IEt1 of binder.
It is preferable to use 0.5 to 301 i (fi part) per 1 SK. Also, in order to promote the crosslinking reaction, #1 anhydride such as methylhexahydrophthalic anhydride, f dibasic acid such as adipic acid, etc. are used as a catalyst. It is also possible to use 5b.
この発明に基づく磁気記録媒体は、？ＩＸ１注粉末色粉
末剤とを含む磁性、ｒ−に架橋剤成分どし゛〔上記化合
物を含有させたこと以外は従来の一気記録誠体と同じ４
成でよい。What is the magnetic recording medium based on this invention? Magnetism containing IX1 Note Powder Color Powder, crosslinking agent component in r
It's fine to be.
磁性粉末としては、７−Ｆｅｌα１ＦｅｓＯａ Ａ１に
者の中間的酸化物−？Ｃｏ含有７−Ｆｅｚ０ｓ 、Ｃｏ
含ｊ４’Ｆ＠１０ａ 。As a magnetic powder, 7-Felα1FesOa A1 is an intermediate oxide. Co-containing 7-Fez0s, Co
Contains j4'F@10a.
Ｃｒｙｓ 、バリウムフェライトなどの酸化物基磁１″
Ｆ：。Oxide-based magnets such as Crys and barium ferrite 1″
F:.
粉末とか、 Ｆｎ、Ｃｒ、 Ｎｌ、 これら金−の合
金、あるいはこれらの金属と他の金属もしくは少逼の非
金属元素ｔｔむ合金などの金属磁性粉末が使用可能であ
る。Powders, metal magnetic powders such as Fn, Cr, Nl, alloys of these metals, or alloys containing these metals and other metals or small amounts of nonmetallic elements can be used.
また、結合剤としては、ポリウレタン樹脂、塩化ビニル
−酢酸ビシル系共−合体、繊維素系樹脂。Further, as the binder, polyurethane resin, vinyl chloride-bisyl acetate type co-combination, cellulose type resin.
ポリビニルブチラール系樹脂、ポリエステル系樹脂、ア
クリル系樹脂、エボ中シ系ＨＢ）Ｊ′ｉｌ、フェノール
系樹脂などを単独、もしくは２橿以上併用とし用いるこ
とができる。A polyvinyl butyral resin, a polyester resin, an acrylic resin, an Evo medium resin (HB) J'il, a phenol resin, etc. can be used alone or in combination of two or more.
また上記磁性信料中には１分散剤、研磨剤、帯１防止剤
、充填剤などの従来より磁気記録媒体に肥用されている
各揮添力ロ剤を適宜配合する。In addition, various volatile additives conventionally used in magnetic recording media, such as a dispersant, an abrasive, an anti-banding agent, and a filler, are appropriately blended into the magnetic material.
なお、ポリグリシジル化合物と、オキサゾリン化合物を
架橋剤として用いるのは、磁゛Ｉ８：Ｉｉｌ用結合剤中
だけでなく、バラフコ−）１ｆｆｉを有する磁気記録媒
体の場合には、バンクコート１−用結合剤用架橋剤とし
ても開用できる。Note that polyglycidyl compounds and oxazoline compounds are used as crosslinking agents not only in the binder for magnetic I8:Iil, but also in the binder for bank coat 1 in the case of magnetic recording media having 1ffi. It can also be used as a crosslinking agent for pharmaceuticals.
〔実７ａｉ例〕 以Ｆに本発明の実施例を述べる。[Actual 7ai example] Examples of the present invention will be described below.
実施例１
Ｃｏｆ有ｒ−ＦｅｍＯｉ（Ｈｅ ６４００ｅ、 ５ＢＥ
Ｔ、 ３５ｉ／ｌ ｓｏｏ這
電部ニトロセルロース（旭化成社裂、セルノ／丹ＩＩ）
１５０直遣部
ポリウレタン樹脂（日本ボリクレタン社ｌ、Ｎ−２３０
１） １００屯意部ヘンガラ（平
均粒子径、０．４μｓ） ４０ボ一部アルミナ（平均
粒子径、０．４μｆｉ） １６重警部カーボンブラ
ック（５ＢＨＴ、 ３００イ／１５１αｍ部
ｉリステン酸 ８１量部ステアリ
ン酸ｎ−ブチル ８重量部シクロヘキサノン
８００１ｆｉｉトルエン
ＳＯＯ色量部上記組成物をボールミル中で
８０時ｌ！１１Ｌ合分散した後、トリチメロールプロパ
ンボリグリフルエーテル（ナガセ化成社製、デナコール
ＥＸ−３２１）を１３Ｖｊｉ虐部と２．２’−（１，３
−フェニレン）ビス（２−オキサゾリン）（式日薬品社
製）′ｆｉ？７重量部加え、さらに３０分間混合分散し
て磁性塗料ｔ−調製した。この磁性塗料を、厚さ１４μ
慣のポリエステルフィルム上に乾ｆｆ１ｌの厚さが５μ
慣となるように塗布、乾燥して磁性層を形成し、カレン
ダ処理後１／２インチ幅に裁断して磁気テープ？作製し
たう
実施例２
実施例１のトリメチロールプロパンポリグリシジルエー
テルをグリセロールポリグリンジルエーテル（ナガセ化
成社裂、デツーコールＥＸ−３１２）に代えた以外は、
実施例１と同様にして磁気テープを作製した。Example 1 Cof-FemOi (He 6400e, 5BE
T, 35i/l soo electric part nitrocellulose (Asahi Kaseisha Rip, Cerno/Tan II)
150 Direct part polyurethane resin (Nippon Polycretan Co., Ltd., N-230
1) 100 parts Hengara (average particle size, 0.4 μs) 40 parts alumina (average particle size, 0.4 μfi) 16 heavy carbon black (5BHT, 300 parts / 151 αm parts i listic acid 81 parts stearin N-Butyl acid 8 parts by weight Cyclohexanone 8001fii Toluene
SOO Color Amount The above composition was milled in a ball mill at 80 hrs. After mixing and dispersing 11L, trithimelorpropane boriglyflu ether (manufactured by Nagase Kasei Co., Ltd., Denacol EX-321) was mixed with 13Vji and 2.2'-(1,3
-phenylene)bis(2-oxazoline) (manufactured by Shikinichi Yakuhin Co., Ltd.)'fi? 7 parts by weight were added and mixed and dispersed for an additional 30 minutes to prepare a magnetic paint. Apply this magnetic paint to a thickness of 14 μm.
The thickness of dry ff1l is 5μ on a conventional polyester film.
Coat it as usual, dry it to form a magnetic layer, then calender it and cut it into 1/2 inch width to make magnetic tape. Preparation Example 2 Except for replacing the trimethylolpropane polyglycidyl ether in Example 1 with glycerol polyglycidyl ether (Nagase Kasei Shafi, Detucol EX-312),
A magnetic tape was produced in the same manner as in Example 1.
比較例１
実施例１のトリメチロールプロパノボリグリンジルエー
テル１３直を部を２０重量部に変え、２゜２’−（１，
３−フェニレン）ビス（２−オキサゾリン）ｔ−加えな
かつ念こと以外は実施例１と同（羨にして磁気テープを
作成した。Comparative Example 1 Trimethylolpropanoborigrindyl ether 13 parts of Example 1 was changed to 20 parts by weight, and 2°2'-(1,
A magnetic tape was prepared in the same manner as in Example 1, except that 3-phenylene)bis(2-oxazoline)t-t was not added.
比較例２
実施例１のトリメチロールプロパンポリグリシジルエー
テルをグリセロールポリグリシジルエーテル２０重量部
に変え、 ２． ２’−（１，３−フェニレン）ビス（
２−オキサゾリン）ｔ−用いなかったこと以外は実施例
１と同様にして磁気テープ金作製した。Comparative Example 2 The trimethylolpropane polyglycidyl ether in Example 1 was replaced with 20 parts by weight of glycerol polyglycidyl ether, and 2. 2'-(1,3-phenylene)bis(
A magnetic tape was prepared in the same manner as in Example 1 except that t-2-oxazoline) was not used.
上記各実施例および比較例で得られた磁気テープについ
て、下記の方法でカラーＳ／Ｎ比、スチル耐久性を試験
した。The magnetic tapes obtained in the above Examples and Comparative Examples were tested for color S/N ratio and still durability using the following methods.
くカラーＳ／Ｎ＞
ＶＨ８方式のＶＴＲｔ−用いてビデオテープに一色りロ
マ忙信号を記録再生し、カラービデオノイズ測定器によ
り、その再生信号のＡＭノイズ分を測定してカラーＳ／
Ｎ比を算出し、基準テープとの相対値で示した。Color S/N> A VH8 system VTR is used to record and play back a single color ROM signal on a videotape, and a color video noise measuring device measures the AM noise component of the playback signal to determine the color S/N.
The N ratio was calculated and expressed as a relative value to the reference tape.
〈スチル耐久゛注〉
Ｖｆ（Ｓ方式のＶＴＲを用いてビデオテープｒスチルモ
ードで再生し、その再生出力レベルが初期値から５ｄＢ
低下するまでの時間を測定した。<Still Endurance Note> Vf (when played back in videotape r still mode using an S-type VTR, the playback output level is 5 dB from the initial value)
The time taken for the temperature to decrease was measured.
以と説明したよりに、磁性塗料を支持体に塗布してなる
磁気記録媒体用結合剤の架橋剤としてポリグリ７ジル化
合物とオキサゾリン化合物を用いることにより、に磁変
換特性を損うことなく、耐久性に優れた磁気記録媒体を
得ることができな。As explained above, by using a polygly7yl compound and an oxazoline compound as a crosslinking agent for a binder for a magnetic recording medium made by coating a magnetic paint on a support, durability can be achieved without impairing the magnetic conversion properties. However, it is not possible to obtain a magnetic recording medium with excellent properties.
Claims (2)
おいて、前記磁性塗料中にポリグリシジル化合物とオキ
サゾリン化合物を用いたことを特徴とする磁気記録媒体
。(1) A magnetic recording medium comprising a support coated with a magnetic paint, characterized in that a polyglycidyl compound and an oxazoline compound are used in the magnetic paint.
キサゾリン化合物中のオキサゾリン環の数の比が０．５
：１〜５：１の範囲となるように配合したことを特徴と
する請求項（１）記載の磁気記録媒体。(2) The ratio of the number of epoxy rings in the polyglycidyl compound to the number of oxazoline rings in the oxazoline compound is 0.5
2. The magnetic recording medium according to claim 1, wherein the magnetic recording medium is blended in a ratio of 1:1 to 5:1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24050388A JPH0289221A (en) | 1988-09-26 | 1988-09-26 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24050388A JPH0289221A (en) | 1988-09-26 | 1988-09-26 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0289221A true JPH0289221A (en) | 1990-03-29 |
Family
ID=17060486
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24050388A Pending JPH0289221A (en) | 1988-09-26 | 1988-09-26 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0289221A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9307969B2 (en) | 2005-06-17 | 2016-04-12 | Vycor Medical, Inc. | Tissue retractor apparatus and methods |
-
1988
- 1988-09-26 JP JP24050388A patent/JPH0289221A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9307969B2 (en) | 2005-06-17 | 2016-04-12 | Vycor Medical, Inc. | Tissue retractor apparatus and methods |
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