JPH02239423A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPH02239423A JPH02239423A JP5888089A JP5888089A JPH02239423A JP H02239423 A JPH02239423 A JP H02239423A JP 5888089 A JP5888089 A JP 5888089A JP 5888089 A JP5888089 A JP 5888089A JP H02239423 A JPH02239423 A JP H02239423A
- Authority
- JP
- Japan
- Prior art keywords
- crosslinking agent
- binder
- recording medium
- magnetic recording
- epoxy
- 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
- 239000003431 cross linking reagent Substances 0.000 claims abstract description 58
- 239000011230 binding agent Substances 0.000 claims abstract description 38
- 239000004593 Epoxy Substances 0.000 claims abstract description 31
- 239000012948 isocyanate Substances 0.000 claims abstract description 30
- 150000002513 isocyanates Chemical class 0.000 claims abstract description 30
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000000758 substrate Substances 0.000 claims abstract description 7
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 6
- 239000001257 hydrogen Substances 0.000 claims abstract description 6
- 150000001408 amides Chemical class 0.000 claims abstract description 4
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 4
- 150000008065 acid anhydrides Chemical class 0.000 claims description 5
- 239000002253 acid Substances 0.000 claims description 3
- 125000000524 functional group Chemical group 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims 1
- AFEQENGXSMURHA-UHFFFAOYSA-N oxiran-2-ylmethanamine Chemical group NCC1CO1 AFEQENGXSMURHA-UHFFFAOYSA-N 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 17
- 239000011248 coating agent Substances 0.000 abstract description 11
- 238000000576 coating method Methods 0.000 abstract description 11
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 abstract description 8
- 150000001412 amines Chemical class 0.000 abstract description 5
- 125000003277 amino group Chemical group 0.000 abstract description 5
- 125000002887 hydroxy group Chemical group [H]O* 0.000 abstract description 5
- 125000003700 epoxy group Chemical group 0.000 abstract description 4
- 150000003573 thiols Chemical class 0.000 abstract description 3
- 125000001273 sulfonato group Chemical group [O-]S(*)(=O)=O 0.000 abstract description 2
- 125000002467 phosphate group Chemical group [H]OP(=O)(O[H])O[*] 0.000 abstract 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract 1
- 238000002360 preparation method Methods 0.000 description 24
- 238000004132 cross linking Methods 0.000 description 10
- -1 Vinyl-vinyl acetate-acrylamide Chemical compound 0.000 description 8
- 239000003973 paint Substances 0.000 description 7
- IVSZLXZYQVIEFR-UHFFFAOYSA-N 1,3-Dimethylbenzene Natural products CC1=CC=CC(C)=C1 IVSZLXZYQVIEFR-UHFFFAOYSA-N 0.000 description 6
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 6
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 229920001577 copolymer Polymers 0.000 description 5
- 239000004971 Cross linker Substances 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 229920005749 polyurethane resin Polymers 0.000 description 4
- 229920002554 vinyl polymer Polymers 0.000 description 4
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 150000002989 phenols Chemical class 0.000 description 3
- 229920006267 polyester film Polymers 0.000 description 3
- 229920002635 polyurethane Polymers 0.000 description 3
- 239000004814 polyurethane Substances 0.000 description 3
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical group OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 229920006322 acrylamide copolymer Polymers 0.000 description 2
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical compound C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 description 2
- 125000000542 sulfonic acid group Chemical group 0.000 description 2
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 2
- 229920002126 Acrylic acid copolymer Polymers 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 235000021355 Stearic acid Nutrition 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 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
- 238000003490 calendering Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 150000007942 carboxylates Chemical class 0.000 description 1
- 125000002843 carboxylic acid group Chemical group 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000012461 cellulose resin Substances 0.000 description 1
- OAWKUMDOADACKG-UHFFFAOYSA-N chloroethene;ethenyl acetate;prop-2-enoic acid Chemical compound ClC=C.OC(=O)C=C.CC(=O)OC=C OAWKUMDOADACKG-UHFFFAOYSA-N 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- OYOFUEDXAMRQBB-UHFFFAOYSA-N cyclohexylmethanediamine Chemical compound NC(N)C1CCCCC1 OYOFUEDXAMRQBB-UHFFFAOYSA-N 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- POULHZVOKOAJMA-UHFFFAOYSA-M dodecanoate Chemical compound CCCCCCCCCCCC([O-])=O POULHZVOKOAJMA-UHFFFAOYSA-M 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 150000003840 hydrochlorides Chemical class 0.000 description 1
- IQPQWNKOIGAROB-UHFFFAOYSA-N isocyanate group Chemical group [N-]=C=O IQPQWNKOIGAROB-UHFFFAOYSA-N 0.000 description 1
- 229940070765 laurate Drugs 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 239000011976 maleic acid Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000008117 stearic acid Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- KSBAEPSJVUENNK-UHFFFAOYSA-L tin(ii) 2-ethylhexanoate Chemical compound [Sn+2].CCCCC(CC)C([O-])=O.CCCCC(CC)C([O-])=O KSBAEPSJVUENNK-UHFFFAOYSA-L 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、基体上に磁性層を設け、さらに下塗り層ある
いはパフクコート層を必要に応じて設けてなる磁気記録
媒体に関し、さらに詳しくは、磁性層、下塗り層および
バンクコート層における結合剤を改良して耐久性を向上
させた前記の磁気記録媒体に関する．
〔従来の技術］
一般に、基体上に磁性層を設け、さらに下塗り層あるい
はバンクコート層を必要に応じて設けてなる磁気記録媒
体は、記録再生時に磁気ヘッド等と激しく摺接するため
、磁性層等の摩耗が少なくて耐久性に優れたものが要求
される．
このため、従来から、磁気記録媒体の磁性層、バンクコ
ート層、下塗り層において、結合剤とともに、イソシア
ネート系架橋剤またはエポキシ系架橋剤を併用して、架
橋硬化することが行われてきた．
ところが、イソシアネート系架橋剤は、結合剤中のＯＨ
基、アミノ基などの活性水素のみならず、空気中の水分
とも反応してすべて消費されるため、結合剤との架橋が
充分に進行せず、塗膜中に強固な網目構造が形成されず
に、得られた磁気記録媒体の耐久性が劣るばかりか、製
品の性能にばらつきが生ずることもしばしばあった．ま
た、エポキシ系架橋剤は、アミノ基、カルボキシル基、
酸無水物などと確実に反応するため、製品のばらつきは
少ないが、エポキシ基と上記官能基との反応が１＝１の
比率で行われるため、エポキシ系架橋剤を多量に使用す
ると、塗膜内に未反応の架橋剤が残留し、これが塗膜表
面にブリードアウトしてドロップアウトの原因になると
いう難点があり、使用量が化学的等モルあるいは等モル
以下では、架橋密度が低下して耐久性に優れた塗膜が得
られにくかった．
さらに、バックコート層の場合は、過剰の架橋剤が磁気
記録媒体の製造あるいは保存中にバックコート層から磁
性層に移転し、これが磁性層表面にたまることによって
ドロップアウトの原因となるという難点があった．
〔発明が解決しようとする問題点〕
本発明は、かかる従来の磁気記録媒体が持っていたドロ
ップアウトの発生や、塗膜の架橋密度の不足という欠点
を解決し、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。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic recording medium comprising a magnetic layer provided on a substrate and further provided with an undercoat layer or a puff coat layer as necessary. The above magnetic recording medium has improved durability by improving the binder in the layer, undercoat layer and bank coat layer. [Prior Art] Generally, a magnetic recording medium, which is formed by providing a magnetic layer on a substrate and further providing an undercoat layer or a bank coat layer as necessary, comes into strong sliding contact with a magnetic head etc. during recording and reproduction, so the magnetic layer etc. A product with excellent durability and low wear is required. For this reason, in the magnetic layer, bank coat layer, and undercoat layer of magnetic recording media, crosslinking and curing have traditionally been carried out by using an isocyanate crosslinking agent or an epoxy crosslinking agent together with a binder. However, isocyanate-based crosslinking agents
As active hydrogen such as radicals and amino groups reacts with moisture in the air and all of it is consumed, crosslinking with the binder does not proceed sufficiently and a strong network structure is not formed in the coating film. In addition, the durability of the resulting magnetic recording media was poor, and the performance of the products often varied. In addition, epoxy crosslinking agents include amino groups, carboxyl groups,
Because it reacts reliably with acid anhydrides, there is little variation in the product, but since the reaction between epoxy groups and the above functional groups takes place at a ratio of 1=1, if a large amount of epoxy crosslinking agent is used, the coating film may However, if the amount used is chemically equimolar or less than equimolar, the crosslinking density will decrease. It was difficult to obtain a coating film with excellent durability. Furthermore, in the case of the backcoat layer, there is a problem in that excess crosslinking agent is transferred from the backcoat layer to the magnetic layer during manufacturing or storage of the magnetic recording medium, and this accumulates on the surface of the magnetic layer, causing dropouts. there were. [Problems to be Solved by the Invention] The present invention solves the drawbacks of such conventional magnetic recording media, such as the occurrence of dropouts and insufficient crosslinking density of the coating film, and has excellent durability. The purpose of the present invention is to provide a magnetic recording medium that has the following characteristics.
本発明者らは、上記欠点を解決するため、鋭意研究を行
った結果、イソシアネート系架橋剤とエポキシ系架橋剤
とを結合剤とともに併用することによって、ドロップア
ウトが少なく、塗膜の架橋密度も高くて、耐久性に優れ
た磁気記録媒体が得られることを見出し、本発明を完成
させるに至った．
本発明において、結合剤とともに併用するイソシアネー
ト系架橋剤は、結合剤中にある活性水素すなわち水酸基
、カルボキシル基、アミノ基、燐酸基、スルホン酸基、
チオール、アミド態窒素などと反応するだけでなく、空
気中の水分とも反応する．その結果アミンを生ずるが、
このアミンはイソシアネート系架橋剤とともに併用する
エポキシ系架橋剤のエポキシ基とも反応して架橋する．
一方、エポキシ系架橋剤のエポキシ基が結合剤中のカル
ボキシル基や酸無水物と反応すると、水酸基を生じるが
、この水酸基はイソシアネート系架橋剤のイソシアネー
ト基と反応するため、複合の架橋が行われる．
しかして、エポキシ系架橋剤とイソシアネート系架橋剤
とを、結合剤とともに併用することによって、架橋密度
の高い塗膜が得られ、磁気記録媒体の耐久性が充分に向
上される．しかし両者を多量に使用しすぎると架橋密度
が上がりすぎて、かえって塗膜が脆くなる傾向がある．
従って、通常、架橋剤の使用量は、エポキシ系架橋剤が
全結合剤に対して０．Ｏｌ〜４０重量％、望ましくは０
．１〜１０重量％、イソシアネート系架橋剤が全結合剤
に対して１〜５０重量％、望ましくは５〜３０重量％と
するのが理想的である．
結合剤としては、水酸基、アミノ基、チオール、カルボ
ン酸基、燐酸基、スルホン酸基、アミド態窒素のうちか
ら選ばれる少なくとも一種の官能基を含んだ活性水素を
有する結合剤、もしくは酸無水物を有する結合剤が好ま
しく使用され、活性水素を持つ結合剤の具体例としては
、従来から用いられている塩化ビニルー酢酸ビニルービ
ニルアルコール共重合体、塩化ビニルー酢酸ビニルーア
クリル酸共重合体、塩化ビニルー酢酸ビニルーアクリル
アミド共重合体、塩化ビニルー酢酸ビニル−Ｎ−１−フ
ェニルエチルアクリルアミド共重合体、繊維素系樹脂、
ポリウレタン樹脂などが挙げられる。また、酸無水物を
存する結合剤の具体例としては、塩化ビニルー詐酸ビニ
ルー無水マレイン酸共重合体が挙げられる．
さらに、これらの結合剤と前記エポキシ系架橋剤および
イソシアネート系架橋剤を併用するに際しては、２−エ
チルヘキシル酸スズ、ラウリル酸鉛などの金属塩触媒や
、１．８−ジアザービシク口（５．４．０） ウンデ
セン−７、トリエチルアミンなどのアミン、およびこれ
らアミンの塩酸塩，カルボン酸塩，フェノール塩．スル
ホン酸塩などを併用してもよい．
〔実施例〕
次に、この発明の実施例について説明する。In order to solve the above drawbacks, the present inventors conducted extensive research and found that by using an isocyanate crosslinking agent and an epoxy crosslinking agent together with a binder, dropouts can be reduced and the crosslinking density of the coating film can be reduced. It was discovered that a magnetic recording medium with high cost and excellent durability could be obtained, and the present invention was completed. In the present invention, the isocyanate crosslinking agent used in combination with the binder includes active hydrogen in the binder, that is, a hydroxyl group, a carboxyl group, an amino group, a phosphoric acid group, a sulfonic acid group,
It not only reacts with thiols and amide nitrogen, but also with moisture in the air. As a result, amines are produced, but
This amine reacts with the epoxy group of the epoxy crosslinking agent used in conjunction with the isocyanate crosslinking agent to cause crosslinking.
On the other hand, when the epoxy group of the epoxy crosslinking agent reacts with the carboxyl group or acid anhydride in the binder, a hydroxyl group is generated, but this hydroxyl group reacts with the isocyanate group of the isocyanate crosslinking agent, resulting in composite crosslinking. ．． By using an epoxy crosslinking agent and an isocyanate crosslinking agent together with a binder, a coating film with high crosslinking density can be obtained, and the durability of the magnetic recording medium can be sufficiently improved. However, if too large amounts of both are used, the crosslinking density increases too much, which tends to make the coating film brittle.
Therefore, the amount of crosslinking agent used is usually 0.00% of the total binder. Ol~40% by weight, preferably 0
．． Ideally, the amount of the isocyanate crosslinking agent is 1 to 50% by weight, preferably 5 to 30% by weight based on the total binder. As a binder, a binder having active hydrogen containing at least one functional group selected from hydroxyl group, amino group, thiol, carboxylic acid group, phosphoric acid group, sulfonic acid group, and amide nitrogen, or acid anhydride. Specific examples of binders having active hydrogen include conventionally used vinyl chloride-vinyl acetate-vinyl alcohol copolymers, vinyl chloride-vinyl acetate-acrylic acid copolymers, Vinyl-vinyl acetate-acrylamide copolymer, vinyl chloride-vinyl acetate-N-1-phenylethyl acrylamide copolymer, cellulose resin,
Examples include polyurethane resin. A specific example of a binder containing an acid anhydride is a vinyl chloride-vinyl sulfate-maleic anhydride copolymer. Furthermore, when using these binders together with the epoxy crosslinking agent and isocyanate crosslinking agent, metal salt catalysts such as tin 2-ethylhexylate and lead laurate, and 1,8-diazabisic acid (5.4. 0) Amines such as undecene-7 and triethylamine, and hydrochlorides, carboxylates, and phenol salts of these amines. It may also be used in combination with sulfonates, etc. [Example] Next, an example of the present invention will be described.
作製例Ｉ
Ｃｏ含有Ｔ Ｆｅ，Ｏ，， ８００重量部
塩化ビニルー酢酸ビニルー無水９Ｑ Ｎマレイン酸共
重合体（日本ゼ
オン社製：４０Ｘ１１０Ａ）
ポリウレタン樹脂（日本ボリウ ９０〃レクン工業社
製： Ｎ−２３０１ ）
カーボンブランク ４０〃（平均粒径３
０ｍａｍ）
アルミナ １６ Ｉ（平均粒
径０．７μｍ）
バルミチン酸 ８ｌステアリン酸ｎ
−ブチル ８ ＃メチルエチルケトン
８００〃トルエン ８００＃
上記組成物をポールミル中で８０時間混合分散した後、
これにイソシアネート系架橋剤（日本ポリウレタン工業
社製：コロネートＬ）１５重量部、エポキシ系架橋剤テ
トラグリシジルメタキジレンジアミン５重量部を加え、
さらに３０分間混合分散して磁性塗料を調製した．この
磁性塗料を厚さ１４μｍのポリエステルフイルム上に乾
燥厚が５μｍとなるように塗布、乾燥して磁性層を形成
し、カレンダー処理後、１／２インチ幅に裁断して磁気
テープを作製した．
作製例２
作製例ｌにおいて、テトラグリシジルメタキシレンジア
ミンに代えて、ビスフェノールＡ型のエポキシ系架橋剤
（油化シエル化学社製：エビコー｝８２７）を同量使用
した以外は、作製例ｌと同様にして磁気テープを作製し
た．
作製例３
作製例ｌにおいて、イソシアネート系架橋剤をコロネー
トＬからコロネートＨＬ， （日本ポリウレタン工業社
製：イソシアネ〜ト系架橋剤）に変更して同量使用した
以外は、作製例ｌと同様にして磁気テープを作製した．
作製例４
作製例１において、イソシアネート系架橋剤コロネート
Ｌの使用量を１５重量部から４重量部に変更し、エポキ
シ系架橋剤テトラグリシジルメクキシレンジアミンの使
用量を５重量部から１重量部に変更した以外は、作製例
１と同様にして磁気テープを作製した．
作製例５
作製例１において、塩化ビニルー酢酸ビニルー無水マレ
イン酸共重合体に代えて、カルボキシル基含有ポリウレ
タン樹脂（分子量３ＸｌＯ’、カルボキシル基量１分子
当たり６．２個）を同量使用した以外は、作製例ｌと同
様にして磁気テープを作製した．
作製例６
作製例５において、エポキシ架橋剤テトラグリシジルメ
タキシレンジアミンに代えて、テトラグリシジル−１．
３−ビスアミノメチルシク口ヘキサンを同量使用した以
外は、作製例５と同様にして磁気テープを作製した．
作製例７
作製例６において、塗布直前の磁性塗料に、１．８〜ジ
アザービシク口（５，４．０）ウンデセン−７のフェノ
ール塩を０．５重量部新たに添加した以外は、作製例６
と同様にして磁気テープを作製した．作製例８
作製例７において、塗布直前の磁性塗料に、１．８−ジ
アザービシク口（５，４．０）ウンデセン−７のフェノ
ール塩に代えて、２−エチルヘキサン酸スズを同量添加
した以外は、作製例７と同様にして磁気テープを作製し
た．
作製例９
作製例ｌにおいて、塩化ビニルー酢酸ビニルー無水マレ
イン酸共重合体に代えて、塩化ビニル−（２−ヒドロキ
シエチルメタクリレート）一マレイン酸共重合体（モル
比８５：１１：４，分子量２×１０４）を同量使用した
以外は、作製例ｌと同様にして磁気テープを作製した。Preparation Example I Co-containing T Fe,O,, 800 parts by weight Vinyl chloride-vinyl acetate-anhydrous 9Q N-maleic acid copolymer (manufactured by Nippon Zeon Co., Ltd.: 40X110A) Polyurethane resin (manufactured by Nippon Boliu 90〃Rekun Kogyo Co., Ltd.: N-2301) Carbon blank 40〃 (average particle size 3
0m) Alumina 16 I (average particle size 0.7μm) Valmitic acid 8l Stearic acid n
-Butyl 8 #Methyl ethyl ketone
800〃Toluene 800#
After mixing and dispersing the above composition in a Pall mill for 80 hours,
To this, 15 parts by weight of an isocyanate crosslinking agent (Coronate L, manufactured by Nippon Polyurethane Industries Co., Ltd.) and 5 parts by weight of an epoxy crosslinking agent tetraglycidylmetachidylenediamine were added.
A magnetic paint was prepared by mixing and dispersing for an additional 30 minutes. This magnetic paint was applied onto a 14 μm thick polyester film to a dry thickness of 5 μm, dried to form a magnetic layer, calendered and cut into 1/2 inch width to produce a magnetic tape. Preparation Example 2 Same as Preparation Example 1 except that the same amount of bisphenol A type epoxy crosslinking agent (manufactured by Yuka Ciel Chemical Co., Ltd.: Ebiko} 827) was used instead of tetraglycidyl metaxylene diamine. A magnetic tape was made using the following method. Preparation Example 3 The same procedure as Preparation Example 1 was carried out, except that in Preparation Example 1, the isocyanate crosslinking agent was changed from Coronate L to Coronate HL (manufactured by Nippon Polyurethane Industries Co., Ltd.: isocyanate crosslinking agent) and the same amount was used. A magnetic tape was made using the following methods. Production Example 4 In Production Example 1, the amount of the isocyanate crosslinking agent Coronate L was changed from 15 parts by weight to 4 parts by weight, and the amount of the epoxy crosslinking agent tetraglycidyl mexylenediamine was changed from 5 parts by weight to 1 part by weight. A magnetic tape was produced in the same manner as Production Example 1 except for the following changes. Preparation Example 5 In Preparation Example 1, the same amount of carboxyl group-containing polyurethane resin (molecular weight 3XlO', carboxyl group weight 6.2 per molecule) was used instead of the vinyl chloride-vinyl acetate-maleic anhydride copolymer. A magnetic tape was produced in the same manner as in Production Example 1. Preparation Example 6 In Preparation Example 5, tetraglycidyl-1.
A magnetic tape was produced in the same manner as in Production Example 5, except that the same amount of 3-bisaminomethylcyclohexane was used. Preparation Example 7 Preparation Example 6 was performed except that 0.5 parts by weight of a phenol salt of 1.8 to diazabic (5,4.0) undecene-7 was newly added to the magnetic paint immediately before coating.
A magnetic tape was prepared in the same manner as above. Preparation Example 8 In Preparation Example 7, the same amount of tin 2-ethylhexanoate was added instead of the phenol salt of 1.8-diazabisic(5,4.0)undecene-7 to the magnetic paint immediately before coating. A magnetic tape was produced in the same manner as in Production Example 7. Preparation Example 9 In Preparation Example 1, vinyl chloride-(2-hydroxyethyl methacrylate) monomaleic acid copolymer (molar ratio 85:11:4, molecular weight 2× A magnetic tape was produced in the same manner as in Production Example 1, except that the same amount of 104) was used.
作製例ｌＯ
カーボンブラック １２０重量部（平均粒
径３０ｍａｍ）
ポリウレタン樹脂（カルボキシ ８０〃ル基含有、分
子量３Ｘ１０’
カルボキシル基量、１分子当
たり６．２個）
メチルエチルケトン ３００〃トルエン
３００〃上記組成物をボールミル中
で８０時間混合分散した後、これにイソシアネート系架
橋剤（日本ポリウレタン工業社製：コロネートＬ）１０
重量部、エポキシ系架橋剤テトラグリシジルメタキシレ
ンジアミン５重量部を加え、さらに３０分間混合分散し
て下塗り塗料を調製した．この下塗り塗料を厚さ１４μ
ｍのポリエステルフイルム上に乾燥厚が０．３μｍとな
るように塗布、乾燥して下塗り層を形成した．
次いで、この下塗り層上に、作製例１と同様にして磁性
層を形成し、磁気テープを作製した。Preparation example lO Carbon black 120 parts by weight (average particle size 30 mm) Polyurethane resin (contains 80 carboxyl groups, molecular weight 3 x 10' carboxyl group weight, 6.2 per molecule) Methyl ethyl ketone 300 Toluene
300〃After mixing and dispersing the above composition in a ball mill for 80 hours, 10% of the isocyanate crosslinking agent (Coronate L manufactured by Nippon Polyurethane Industries) was added to the mixture.
5 parts by weight of epoxy crosslinking agent tetraglycidyl metaxylene diamine were added, and the mixture was further mixed and dispersed for 30 minutes to prepare an undercoat paint. Apply this undercoat to a thickness of 14μ.
It was coated on a polyester film of 0.3 m to a dry thickness of 0.3 μm and dried to form an undercoat layer. Next, a magnetic layer was formed on this undercoat layer in the same manner as in Production Example 1 to produce a magnetic tape.
作製例１１
作製例１０において、エポキシ架橋剤テトラグリシジル
メタキシレンジアミンに代えて、イソシアネート架橋剤
コロネートＨＬを同量使用した以外は、作製例１０と同
様にして磁気テープを作製した．
作製例１２
作製例ＩＯにおいて調整した下塗り塗料をそのままバン
クコート層塗料として使用し、作製例１と同様にして磁
性層を形成したポリエステルフイルムの裏面に、乾燥厚
が０．３μｍとなるように塗布、乾燥してバンクコート
層を形成した。しかる後、１／２インチ幅に裁断して磁
気テープを作製した．
作製例１３
作製例１２において、エポキシ架橋剤テトラグリシジル
メタキシレンジアミンに代えて、イソシアネート架橋剤
コロネートＨＬを同量使用した以外は、作製例ｌ２と同
様にして磁気テープを作製した．
作製例ｌ４
作製例１において、イソシアネート系架橋剤コロネート
Ｌの使用量を１５重量部から２０重量部に変更し、エポ
キシ系架橋剤テトラグリシジルメタキシレンジアミンを
省いた以外は、作製例ｌと同様にして磁気テープを作製
した．
作製例ｌ５
作製例１において、エポキシ系架橋剤テトラグリシジル
メタキシレンジアミンの使用量を５重量部から１０重量
部に変更し、イソシアネート系架橋剤コロネートＬを省
いた以外は、作製例ｌと同様にして磁気テープを作製し
た。Preparation Example 11 A magnetic tape was prepared in the same manner as in Preparation Example 10, except that the same amount of the isocyanate crosslinker Coronate HL was used in place of the epoxy crosslinker tetraglycidyl metaxylene diamine. Preparation Example 12 Using the undercoat paint prepared in Preparation Example IO as it is as a bank coat layer paint, apply it to the back side of a polyester film on which a magnetic layer has been formed in the same manner as in Preparation Example 1 so that the dry thickness is 0.3 μm. , and dried to form a bank coat layer. Thereafter, it was cut into 1/2 inch width to produce magnetic tape. Preparation Example 13 A magnetic tape was prepared in the same manner as Preparation Example 12, except that the same amount of isocyanate crosslinker Coronate HL was used in place of the epoxy crosslinker tetraglycidyl metaxylene diamine. Production Example 14 Same as Production Example 1 except that the amount of the isocyanate crosslinking agent Coronate L used was changed from 15 parts by weight to 20 parts by weight, and the epoxy crosslinking agent tetraglycidyl metaxylene diamine was omitted. A magnetic tape was made using the following methods. Production Example 15 Same as Production Example 1 except that the amount of the epoxy crosslinking agent tetraglycidyl metaxylene diamine was changed from 5 parts by weight to 10 parts by weight, and the isocyanate crosslinking agent Coronate L was omitted. A magnetic tape was manufactured using the following steps.
各作製例で得られた磁気テープをＶＨＳカセットに組み
込み、ビデオデッキにより一定のビデオ信号を記録し、
再生した静止画像の出力が６ｄＢ低下するまでの時間を
測定してスチル耐久性を測定した．また、連続走行によ
って、ドロップアウトが初期値の３倍になるまでの繰り
返し回数を測定して耐久性を調べた．
下記第１表はその結果である．
第１表
〔発明の効果〕
上記第１表から明らかなように、作製例ｌないしｌ３で
得られた磁気テープは、作製例Ｉ４および１５で得られ
た磁気テープに比し、いずれもスチル耐久性および耐久
性がよく、このことから磁気記録媒体の磁性層、下塗り
層、バックコート層等に使用する結合剤に、イソシアネ
ート系架橋剤とエポキシ系架橋剤を併用して得られるこ
の発明の磁気記録媒体は、架橋密度が向上し、ドロップ
アウトが少なくて、耐久性に優れていることがわかる。The magnetic tape obtained in each production example was incorporated into a VHS cassette, and a certain video signal was recorded using a video deck.
Still durability was measured by measuring the time until the output of the reproduced still image decreased by 6 dB. We also investigated durability by running continuously and measuring the number of repetitions until dropout reached three times the initial value. Table 1 below shows the results. Table 1 [Effects of the Invention] As is clear from Table 1 above, the magnetic tapes obtained in Production Examples 1 to 13 have better still durability than the magnetic tapes obtained in Production Examples I4 and 15. The magnetic material of this invention is obtained by using an isocyanate crosslinking agent and an epoxy crosslinking agent in combination as a binder used in the magnetic layer, undercoat layer, backcoat layer, etc. of a magnetic recording medium. It can be seen that the recording medium has improved crosslinking density, less dropouts, and excellent durability.
特許出願人 日立マクセル株式会社Patent applicant: Hitachi Maxell, Ltd.
Claims (1)
するエポキシ系架橋剤とイソシアネート系架橋剤とを含
む磁性層を設けたことを特徴とする磁気記録媒体 ２、基体と磁性層との間に、さらに結合剤と、この結合
剤に対して作用するエポキシ系架橋剤とイソシアネート
系架橋剤とを含む下塗り層を設けた請求項１記載の磁気
記録媒体 ３、基体の裏面に、さらに結合剤と、この結合剤に対し
て作用するエポキシ系架橋剤とイソシアネート系架橋剤
とを含むバックコート層を設けた請求項１または２記載
の磁気記録媒体 ４、基体と磁性層との間に、結合剤と、この結合剤に対
して作用するエポキシ系架橋剤とイソシアネート系架橋
剤とを含む下塗り層を設けたことを特徴とする磁気記録
媒体 ５、表面に磁性層を設けた基体の裏面に、結合剤と、こ
の結合剤に対して作用するエポキシ系架橋剤とイソシア
ネート系架橋剤とを含むバックコート層を設けたことを
特徴とする磁気記録媒体６、結合剤が、活性水素もしく
は酸無水物を有する結合剤である請求項１ないし５記載
の磁気記録媒体 ７、活性水素を有する結合剤が、水酸基、アミノ基、チ
オール、カルボン酸基、燐酸基、スルホン酸基、アミド
態窒素のうちから選ばれる少なくとも一種の官能基を含
む結合剤である請求項６記載の磁気記録媒体 ８、エポキシ系架橋剤を結合剤全量に対して０．０１〜
４０重量％含有させ、イソシアネート系架橋剤を結合剤
全量に対して１〜５０重量％含有させた請求項１ないし
７記載の磁気記録媒体 ９、結合剤全量に対して０．０１〜１０重量％のエポキ
シ系架橋剤および５〜３０重量％のイソシアネート系架
橋剤を含有させた請求項８記載の磁気記録媒体 １０、エポキシ系架橋剤が、Ｎ−グリシジルアミン構造
を有するエポキシ系架橋剤である請求項１ないし９記載
の磁気記録媒体[Claims] 1. A magnetic recording medium characterized in that a magnetic layer containing a binder, and an epoxy crosslinking agent and an isocyanate crosslinking agent that act on the binder is provided on the surface of a substrate. 2. The magnetic recording medium 3 according to claim 1, further comprising an undercoat layer containing a binder, and an epoxy crosslinking agent and an isocyanate crosslinking agent that act on the binder, between the substrate and the magnetic layer. 3. The magnetic recording medium 4 according to claim 1, further comprising a backcoat layer on the back surface of the substrate, further comprising a binder, and an epoxy crosslinking agent and an isocyanate crosslinking agent that act on the binder. A magnetic recording medium 5 characterized in that an undercoat layer containing a binder and an epoxy crosslinking agent and an isocyanate crosslinking agent that act on the binder is provided between the magnetic layer and the magnetic layer. Magnetic recording medium 6, characterized in that a back coat layer containing a binder, and an epoxy crosslinking agent and an isocyanate crosslinking agent that act on the binder is provided on the back surface of a substrate provided with a layer. 6. The magnetic recording medium 7 according to claim 1, wherein the agent is a binder having active hydrogen or an acid anhydride; The magnetic recording medium 8 according to claim 6, wherein the binder is a binder containing at least one functional group selected from acid groups and amide nitrogen, and the epoxy crosslinking agent is contained in an amount of 0.01 to 0.01 to the total amount of the binder.
8. The magnetic recording medium 9 according to claim 1, wherein the isocyanate-based crosslinking agent is contained in an amount of 1 to 50% by weight based on the total amount of the binder, and 0.01 to 10% by weight based on the total amount of the binder. The magnetic recording medium 10 according to claim 8, wherein the epoxy crosslinking agent contains an epoxy crosslinking agent and 5 to 30% by weight of an isocyanate crosslinking agent, and the epoxy crosslinking agent is an epoxy crosslinking agent having an N-glycidylamine structure. Magnetic recording medium according to items 1 to 9
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5888089A JPH02239423A (en) | 1989-03-10 | 1989-03-10 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5888089A JPH02239423A (en) | 1989-03-10 | 1989-03-10 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02239423A true JPH02239423A (en) | 1990-09-21 |
Family
ID=13097078
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5888089A Pending JPH02239423A (en) | 1989-03-10 | 1989-03-10 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02239423A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7754355B2 (en) * | 2004-04-23 | 2010-07-13 | Fujifilm Corporation | Magnetic recording medium |
-
1989
- 1989-03-10 JP JP5888089A patent/JPH02239423A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7754355B2 (en) * | 2004-04-23 | 2010-07-13 | Fujifilm Corporation | Magnetic recording medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR890003039B1 (en) | Magnetic recording carrier | |
| US4634627A (en) | Magnetic recording medium comprising a surface-treated abrasive | |
| JPH02239423A (en) | Magnetic recording medium | |
| JP2647524B2 (en) | Magnetic recording media | |
| JPS61123017A (en) | Magnetic recording medium | |
| JPH0470686B2 (en) | ||
| JPH0777022B2 (en) | Magnetic recording medium | |
| JPH0618062B2 (en) | Magnetic recording medium and manufacturing method thereof | |
| US5212019A (en) | Magnetic recording medium having a magnetic layer containing ferromagnetic metal powder, binder, fatty acid ester, and a specified branched chain fatty acid | |
| US5094910A (en) | Magnetic recording medium | |
| JPH0770044B2 (en) | Magnetic recording medium | |
| US5110680A (en) | Magnetic recording medium | |
| US6077595A (en) | Magnetic recording medium | |
| KR0148754B1 (en) | Method of manufacturing magnetic recording medium | |
| JPH02260608A (en) | Fine partice of ferromagnetic metallic iron, manufacture thereof, and magnetic recording medium using same | |
| JPH06282839A (en) | Magnetic recording medium | |
| JPS63166014A (en) | Magnetic recording medium | |
| JPH01118214A (en) | Magnetic recording medium | |
| JPS634415A (en) | Magnetic recording medium | |
| JPH0374480A (en) | Coating composition and magnetic recording medium containing the same | |
| JPH0668458A (en) | Magnetic recording medium | |
| JPS60185225A (en) | Magnetic recording medium | |
| JPS61134916A (en) | Magnetic recording medium | |
| JPS6339133A (en) | Magnetic recording medium | |
| JPH02108233A (en) | Magnetic recording medium |