JPH0554366A - Magnetic recording medium and production thereof - Google Patents
Magnetic recording medium and production thereofInfo
- Publication number
- JPH0554366A JPH0554366A JP23734891A JP23734891A JPH0554366A JP H0554366 A JPH0554366 A JP H0554366A JP 23734891 A JP23734891 A JP 23734891A JP 23734891 A JP23734891 A JP 23734891A JP H0554366 A JPH0554366 A JP H0554366A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- layer
- recording medium
- back coat
- magnetic recording
- 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
Landscapes
- Paints Or Removers (AREA)
- Magnetic Record Carriers (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、表面に磁性層を有する
基体の裏面にバックコ−ト層を設けた磁気テ−プなどの
磁気記録媒体およびその製造方法に関し、さらに詳しく
は、バックコ−ト層表面の摩擦係数が小さくて、走行安
定性に優れた磁気記録媒体とその製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium such as a magnetic tape in which a back coat layer is provided on the back surface of a substrate having a magnetic layer on the front surface, and a method for producing the same, and more specifically, a back coat The present invention relates to a magnetic recording medium having a small friction coefficient on the layer surface and excellent running stability, and a method for manufacturing the same.
【０００２】[0002]
【従来の技術】オ−ディオテ−プ、ビデオテ−プ、デ−
タテ−プ等の磁気記録媒体においては、記録密度の向上
を目的として、極めて平滑性の良好なポリエステルフィ
ルム等を基体として使用し、かつ非常に微細な磁性粉末
を使用するなどして磁性層の表面を平滑にすることが行
われている。ところが、平滑な基体を使用するほど走行
時にテ−プカ−トリッジのガイドロ−ラおよびデッキの
ガイドロ−ラ等との摩擦係数が大きくなり、走行が不安
定になる。このため、摩擦係数を低減し走行安定性を改
善する目的で、表面に磁性層を有する基体の裏面に、非
磁性粉末を結合剤樹脂とともに塗着してバックコ−ト層
を形成することが広く行われており、さらに、バックコ
−ト層表面の摩擦係数を低減して走行安定性を改善する
という機能を具備させるために、非磁性粉末および結合
剤樹脂などの材料の改良や、バックコ−ト層の表面粗さ
の改良が行われている。（特開平１−２３２５２５号）2. Description of the Related Art Audio tape, video tape, data
In a magnetic recording medium such as a tape, for the purpose of improving the recording density, a polyester film or the like having extremely good smoothness is used as a substrate, and a very fine magnetic powder is used to form a magnetic layer. The surface is smoothed. However, the smoother the substrate is, the larger the friction coefficient between the guide roller of the tape cartridge and the guide roller of the deck during traveling becomes, and the traveling becomes unstable. Therefore, for the purpose of reducing the friction coefficient and improving running stability, it is common to form a back coat layer by coating a non-magnetic powder with a binder resin on the back surface of a substrate having a magnetic layer on the surface. Further, in order to provide the function of reducing the friction coefficient of the surface of the back coat layer and improving the running stability, improvement of materials such as non-magnetic powder and binder resin, and back coat Improvements in the surface roughness of the layers have been made. (JP-A-1-232525)
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、非磁性
粉末の形状や結合剤樹脂の物性、あるいは非磁性粉末と
結合剤樹脂との混合比の検討などによりバックコ−ト層
の表面粗さの最適化を図り、バックコ−ト層表面の摩擦
係数を下げることはできるが、磁気テ−プなどの複雑な
実走行系での走行安定性を確保することは容易でなく、
未だ、複雑な実走行系における走行安定性の改善は充分
でない。However, the surface roughness of the backcoat layer is optimized by considering the shape of the non-magnetic powder, the physical properties of the binder resin, and the mixing ratio of the non-magnetic powder and the binder resin. It is possible to reduce the friction coefficient of the surface of the backcoat layer, but it is not easy to secure the running stability in a complicated actual running system such as a magnetic tape.
The improvement of running stability in a complicated actual running system is not yet sufficient.
【０００４】[0004]
【課題を解決するための手段】この発明はかかる現状に
鑑み種々検討を行った結果なされたもので、表面に磁性
層を有する基体の裏面に、走行方向に連続した凸状の筋
を表面に有するバックコ−ト層を設けることによって、
バックコ−ト層表面の摩擦係数を充分に低減し、磁気テ
−プなどの複雑な実走行系で充分な走行安定性が得られ
るようにしたものである。The present invention has been made as a result of various investigations in view of the above-mentioned present situation. A back surface of a substrate having a magnetic layer on the front surface thereof has convex streaks continuous in the traveling direction on the front surface. By providing a backcoat layer having
The friction coefficient on the surface of the back coat layer is sufficiently reduced so that sufficient running stability can be obtained in a complicated actual running system such as a magnetic tape.
【０００５】この発明において、バックコ−ト層表面に
設けられる連続した凸状の筋は、高さが１０ｎｍよりも
小さいと所期の効果が得られず、また３０ｎｍよりも大
きい場合は、磁気テ−プとしてロ−ル状にあるいはリ−
ルに巻き取った際に磁性層に変形を生じ、磁気ヘッドと
のスペ−シングロスが大きくなって出力の低下をまねく
おそれがあるため、１０〜３０ｎｍの範囲内にするのが
好ましい。In the present invention, the continuous convex streak provided on the surface of the back coat layer does not provide the desired effect when the height is less than 10 nm, and when the height is greater than 30 nm, the magnetic stripe is not formed. As rolls or rolls
It is preferable that the thickness is in the range of 10 to 30 nm, because the magnetic layer may be deformed when wound up on the magnetic tape and the spacing loss between the magnetic head and the magnetic head may increase, leading to a decrease in output.
【０００６】また、連続した凸状の筋の間隔は、１５０
〜５００μｍの範囲内にするのが好ましく、１５０μｍ
よりも小さいとバックコ−ト層表面の摩擦係数が増大す
るばかりでなく、かえって磁気テ−プの蛇行等の走行不
良を起こし、また５００μｍよりも大きいと所期の効果
が得られにくい。The interval between continuous convex streaks is 150
To 500 μm, preferably 150 μm
If it is smaller than this, not only the friction coefficient on the surface of the back coat layer increases, but on the contrary, running failure such as meandering of the magnetic tape occurs, and if it is larger than 500 μm, it is difficult to obtain the desired effect.
【０００７】さらに、連続した凸状の筋間の表面粗さ
は、中心線平均粗さＲａで 0.015μｍ以下にするのが好
ましく、 0.015μｍよりも大きいと含有する非磁性粉末
の脱落等が起こり、これがドロップアウトやガイドロ−
ラの汚染の原因となる。Further, the surface roughness between the continuous convex streaks is preferably 0.015 μm or less in terms of the center line average roughness Ra. If it is larger than 0.015 μm, the non-magnetic powder contained may come off. , This is a dropout or guide lo
It causes the contamination of LA.
【０００８】このような連続した凸状の筋をバックコ−
ト層表面に形成する方法としては、従来から一般的な間
接塗布方式として知られるグラビア塗布方式やリバ−ス
塗布方式による場合、非磁性粉末を結合剤樹脂、有機溶
剤およびその他の必要成分とともに混合分散して調製し
たバックコ−ト層用塗料を、これらの塗布方式で表面に
磁性層を有する基体の裏面に塗布し、この塗布により形
成されたバックコ−ト層塗膜面をスム−ジング処理曲面
を有するスム−ザのスム−ジング処理曲面でスム−ジン
グする方法で行われる。Such continuous convex streaks are back-coated.
As a method of forming on the surface of the coating layer, in the case of a gravure coating method or a reverse coating method conventionally known as a general indirect coating method, a nonmagnetic powder is mixed with a binder resin, an organic solvent and other necessary components. The coating material for the back coat layer prepared by dispersion is applied to the back surface of the substrate having the magnetic layer on the surface by these coating methods, and the coating surface of the back coat layer formed by this coating is subjected to the smoothing treatment curved surface. Smoothing processing of a smoother having a smoothing method.
【０００９】この場合、前記の連続した凸状の筋を良好
に形成するため、スム−ザのスム−ジング処理曲面は、
曲率半径を１〜１０ｍｍの範囲内にするのが好ましく、
さらに、連続した凸状の筋間の表面粗さを維持する上
で、スム−ザのスム−ジング処理曲面の表面粗さは中心
線平均粗さＲａで0.01μｍ以下にするのが好ましい。In this case, in order to favorably form the continuous convex streaks, the smoothing surface of the smoother is
It is preferable to set the radius of curvature within the range of 1 to 10 mm,
Further, in order to maintain the surface roughness between the continuous convex streaks, the surface roughness of the smoothing smoothing surface of the smoother is preferably 0.01 μm or less in terms of the center line average roughness Ra.
【００１０】また、このような連続した凸状の筋を直接
塗布方式であるエクストル−ジョン塗布方式で、バック
コ−ト層に形成する場合は、間接塗布方式の場合のスム
−ザに相当するドクタ−エッジのエッジ部を曲面化して
スム−ジング処理曲面とし、このエッジ部のスム−ジン
グ処理曲面で、基体の裏面にバックコ−ト層用塗料を塗
布して形成されたバックコ−ト層塗膜面をスム−ジング
して行われる。この場合も、エッジ部のスム−ジング処
理曲面は、曲率半径を１〜１０ｍｍの範囲内とし、スム
−ジング処理曲面の表面粗さを中心線平均粗さＲａで0.
01μｍ以下にするのが好ましい。Further, in the case of forming such continuous convex streaks on the back coat layer by the extrusion coating method which is a direct coating method, a doctor corresponding to a smoother in the case of the indirect coating method is used. -The edge portion of the edge is curved to form a smoothing-treated curved surface, and the backcoat layer coating film formed by applying the coating material for the backcoat layer to the back surface of the substrate with the smoothing-treated curved surface of the edge portion. Smoothing the surface. Also in this case, the smoothing-treated curved surface of the edge portion has a radius of curvature in the range of 1 to 10 mm, and the surface roughness of the smoothing-treated curved surface is 0.
It is preferably set to 01 μm or less.
【００１１】バックコ−ト層に使用される非磁性粉末と
しては、アセチレンブラック、サ−マルブラックなどの
カ−ボンブラック、アルミナ、チタニア、炭酸カルシウ
ム、硫酸バリウム、ベンガラ、ジルコニア、ガ−ネッ
ト、酸化クロム、酸化マグネシウムなどの金属酸化物な
ど、一般に磁気記録媒体のバックコ−ト層に使用される
ものがいずれも使用され、平均粒径0.01〜１μｍのもの
が好適に使用される。使用量は、連続した凸状の筋を良
好に形成するため結合剤樹脂との合計量に対して３０〜
６０重量％の範囲内にするのが好ましい。The non-magnetic powder used in the back coat layer includes carbon black such as acetylene black and thermal black, alumina, titania, calcium carbonate, barium sulfate, red iron oxide, zirconia, garnet, and oxide. Any of those generally used for the back coat layer of the magnetic recording medium such as metal oxides such as chromium and magnesium oxide are used, and those having an average particle diameter of 0.01 to 1 μm are preferably used. The amount used is 30 to 30% with respect to the total amount with the binder resin in order to favorably form continuous convex streaks.
It is preferably in the range of 60% by weight.
【００１２】また、結合剤樹脂としては、ニトロセルロ
−ス、アセチルセルロ−ス、メチルセルロ−ス、エチル
セルロ−スなどの繊維素系樹脂、塩化ビニル−酢酸ビニ
ル−ビニルアルコ−ル共重合体、塩化ビニル−酢酸ビニ
ル−マレイン酸共重合体、塩化ビニル−塩化ビニリデン
共重合体などの塩化ビニル系樹脂、ポリエステル系樹
脂、ポリウレタン系樹脂、フェノ−ル系樹脂、エポキシ
系樹脂、またはこれらの混合物等、一般に磁気記録媒体
のバックコ−ト層に使用されるものがいずれも使用され
る。As the binder resin, nitrocellulose, acetylcellulose, methylcellulose, ethylcellulose and other fibrous resin, vinyl chloride-vinyl acetate-vinyl alcohol copolymer, vinyl chloride- Vinyl acetate-maleic acid copolymers, vinyl chloride-vinylidene chloride copolymers and other vinyl chloride resins, polyester resins, polyurethane resins, phenol resins, epoxy resins, or mixtures thereof are generally magnetic. Any of those used for the back coat layer of the recording medium may be used.
【００１３】さらに、有機溶剤としては、シクロヘキサ
ノン、メチルエチルケトン、メチルイソブチルケトンな
どのケトン系溶剤、酢酸エチル、酢酸ブチルなどのエス
テル系溶剤、ベンゼン、トルエン、キシレンなどの芳香
族炭化水素系溶剤、イソプロピルアルコ−ルなどのアル
コ−ル系溶剤、ジメチルスルホキシドなどの酢アミド系
溶剤、テトラヒドロフラン、ジオキサンなどのエ−テル
系溶剤など、使用する結合剤樹脂を溶解するのに適した
溶剤が、特に制限されることなく単独あるいは二種以上
混合して使用される。Further, as the organic solvent, ketone solvents such as cyclohexanone, methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate and butyl acetate, aromatic hydrocarbon solvents such as benzene, toluene and xylene, and isopropyl alcohol. Solvents suitable for dissolving the binder resin to be used are particularly limited, such as alcohol-based solvents such as styrene-based solvents, acetamide-based solvents such as dimethylsulfoxide, ether-based solvents such as tetrahydrofuran and dioxane. Used alone or as a mixture of two or more kinds.
【００１４】なお、バックコ−ト層用塗料中には、この
他、通常使用されている各種添加剤、たとえば、潤滑剤
などを任意に添加使用してもよい。In addition to the above, various commonly used additives such as lubricants may be optionally added to the back coat layer coating material.
【００１５】基体の表面に形成される磁性層は、γ−Ｆ
ｅ2 Ｏ3粉末、Ｆｅ3 Ｏ4 粉末、Ｃｏ含有γ−Ｆｅ2 Ｏ
3 粉末、Ｃｏ含有Ｆｅ3 Ｏ4 粉末、バリウムフェライ
ト、ストロンチウムフェライト等の六方晶フェライト粉
末、ＣｒＯ2 粉末、Ｆｅ粉末、Ｃｏ粉末、Ｆｅ−Ｎｉ粉
末など従来一般に使用される磁性粉末を、従来一般に使
用される結合剤樹脂、有機溶剤およびその他の必要成分
とともに混合分散して磁性塗料を調製し、この磁性塗料
を基体の表面に塗布、乾燥するなどの方法で形成され
る。この他、Ｃｏ、Ｎｉ、Ｆｅ、Ｃｏ−Ｎｉ合金、Ｃｏ
−Ｃｒ合金などの強磁性材を、真空蒸着、イオンプレ−
ティング、スパッタリング、メッキ等の手段で基体の表
面に被着するなどの方法でも形成される。The magnetic layer formed on the surface of the substrate is γ-F.
e 2 O 3 powder, Fe 3 O 4 powder, Co-containing γ-Fe 2 O
3 powder, Co-containing Fe 3 O 4 powder, hexagonal ferrite powder such as barium ferrite and strontium ferrite, CrO 2 powder, Fe powder, Co powder, Fe-Ni powder, etc. It is formed by a method in which a magnetic coating material is prepared by mixing and dispersing it with a binder resin, an organic solvent, and other necessary components, and the magnetic coating material is applied to the surface of a substrate and dried. In addition, Co, Ni, Fe, Co-Ni alloy, Co
-Ferromagnetic materials such as Cr alloys are vacuum-deposited and ion-precoated.
It is also formed by a method such as coating on the surface of the substrate by means of coating, sputtering, plating or the like.
【００１６】[0016]
【実施例】次ぎに、この発明の実施例について説明す
る。 実施例１ Ｃｏ含有γ−Ｆｅ2 Ｏ3 磁性粉末 ５００重量部 ニトロセルロ−ス（旭化成社製；ニトロセルロ−スＬ１／２） ６５ 〃 ポリウレタン樹脂（日本ポリウレタン工業社製；ニッポラン ３８ 〃 Ｎ−２３０１） イソシアネ−ト化合物（日本ポリウレタン工業社製；コロネ ２５ 〃 −トＬ） アルミナ（住友化学工業社製；ＡＫＰ−２８） ４０ 〃 カ−ボンブラック ３ 〃 ステアリン酸−ｎ−ブチル ６ 〃 ステアリン酸 ５ 〃 シクロヘキサノン ６００ 〃 トルエン ６００ 〃 上記の組成物をボ−ルミルで７２時間混合分散して磁性
塗料を調製し、この磁性塗料を厚さ１４μｍのポリエス
テルフィルムの表面に、乾燥後の厚さが 3.5μｍとなる
ように塗布、乾燥し、カレンダ処理して磁性層を形成し
た。Next, examples of the present invention will be described. Example 1 Co-containing γ-Fe 2 O 3 magnetic powder 500 parts by weight Nitrocellulose (manufactured by Asahi Kasei Co., Ltd .; Nitrocellulos L1 / 2) 65 〃 Polyurethane resin (manufactured by Nippon Polyurethane Industry Co., Ltd .; Nipporan 38〃 N-2301) Isocyanate -To compound (Nippon Polyurethane Industry Co., Ltd .; Corone 25 〃-L) Alumina (Sumitomo Chemical Co., Ltd .; AKP-28) 40 〃 Carbon black 3 〃 Stearic acid-n-butyl 6 〃 Stearic acid 5 〃 Cyclohexanone 600 〃 Toluene 600 〃 The above composition is mixed and dispersed in a ball mill for 72 hours to prepare a magnetic paint, and the magnetic paint is dried on a surface of a polyester film having a thickness of 14 μm to have a thickness of 3.5 μm. In this way, the magnetic layer was formed by coating, drying and calendering.
【００１７】次いで、下記のバックコ−ト層組成物をボ
−ルミルで７２時間混合分散してバックコ−ト層用塗料
を調製し、このバックコ−ト層用塗料を前記の磁性層が
形成されたポリエステルフィルムの裏面に、グラビア塗
布方式により塗布速度７０ｍ／min で塗布し、スム−ジ
ング処理曲面の曲率半径が２ｍｍ、表面粗さが中心線平
均粗さＲａで 0.008μｍのスム−ザを使用してスム−ジ
ングを行い、乾燥後の厚さが１μｍのバックコ−ト層を
形成した。しかる後、８ｍｍ幅に裁断して磁気テ−プを
作製した。 バックコ−ト層組成物 カ−ボンブラック（米国キャボット社製；ブラックパ−ル８ ４０重量部 ００） アルミナ（住友化学工業社製；ＡＫＰ−２８） ２ 〃 ニトロセルロ−ス（旭化成社製；ニトロセルロ−スＬ１／２） ５０ 〃 ポリウレタン樹脂（日本ポリウレタン工業社製；ニッポラン ３０ 〃 Ｎ−２３０１） イソシアネ−ト化合物（日本ポリウレタン工業社製；コロネ ２０ 〃 −トＬ） ミリスチン酸 ２ 〃 シクロヘキサノン ２８５ 〃 トルエン ２８５ 〃Then, the following backcoat layer composition was mixed and dispersed in a ball mill for 72 hours to prepare a backcoat layer coating material, and the backcoat layer coating material was formed into the above magnetic layer. It is coated on the back side of the polyester film by the gravure coating method at a coating speed of 70 m / min, and a smoother with a radius of curvature of the smoothing surface of 2 mm and a centerline average roughness Ra of 0.008 μm is used. Smoothing was performed to form a backcoat layer having a thickness of 1 μm after drying. Then, it was cut into a width of 8 mm to produce a magnetic tape. Backcoat layer composition Carbon black (manufactured by Cabot, USA; Black par 840 parts by weight 00) Alumina (manufactured by Sumitomo Chemical Co., Ltd .; AKP-28) 2 〃 Nitrocellulose (manufactured by Asahi Kasei; Nitrocellulose) L 1/2) 50 〃 Polyurethane resin (Nippon Polyurethane Industry Co., Ltd .; Nipolan 30 〃 N-2301) Isocyanate compound (Nihon Polyurethane Industry Co., Ltd .; Corone 20 〃-L) Myristic acid 2 〃 Cyclohexanone 285 〃 Toluene 285 〃
【００１８】実施例２ 実施例１におけるバックコ−ト層の形成において、バッ
クコ−ト層用塗料の塗布速度を７０ｍ／min から１００
ｍ／min に変更した以外は、実施例１と同様にして磁気
テ−プを作製した。Example 2 In the formation of the backcoat layer in Example 1, the coating speed of the backcoat layer coating material was changed from 70 m / min to 100.
A magnetic tape was produced in the same manner as in Example 1 except that the magnetic tape was changed to m / min.
【００１９】実施例３ 実施例１におけるバックコ−ト層の形成において、バッ
クコ−ト層用塗料の塗布速度を７０ｍ／min から１５０
ｍ／min に変更した以外は、実施例１と同様にして磁気
テ−プを作製した。Example 3 In forming the backcoat layer in Example 1, the coating speed of the coating material for the backcoat layer was 70 m / min to 150 m / min.
A magnetic tape was produced in the same manner as in Example 1 except that the magnetic tape was changed to m / min.
【００２０】実施例４ 実施例１におけるバックコ−ト層の形成において、スム
−ジング処理曲面の曲率半径が２ｍｍ、表面粗さが中心
線平均粗さＲａで 0.008μｍのスム−ザに代えて、スム
−ジング処理曲面の曲率半径が５ｍｍ、表面粗さが中心
線平均粗さＲａで 0.005μｍのスム−ザを使用した以外
は、実施例１と同様にしてスム−ジングを行い、磁気テ
−プを作製した。Example 4 In the formation of the backcoat layer in Example 1, instead of a smoother having a radius of curvature of a smoothing surface of 2 mm and a center line average roughness Ra of 0.008 μm, instead of a smoother, The smoothing treatment was performed in the same manner as in Example 1 except that a smoother having a radius of curvature of 5 mm and a surface roughness of 0.005 μm in terms of centerline average roughness Ra was used. I made a cup.
【００２１】実施例５ 実施例４におけるバックコ−ト層の形成において、バッ
クコ−ト層用塗料の塗布速度を７０ｍ／min から１００
ｍ／min に変更した以外は、実施例４と同様にして磁気
テ−プを作製した。Example 5 In the formation of the back coat layer in Example 4, the coating rate of the back coat layer coating material was changed from 70 m / min to 100.
A magnetic tape was produced in the same manner as in Example 4 except that the magnetic tape was changed to m / min.
【００２２】実施例６ 実施例４におけるバックコ−ト層の形成において、バッ
クコ−ト層用塗料の塗布速度を７０ｍ／min から１５０
ｍ／min に変更した以外は、実施例４と同様にして磁気
テ−プを作製した。Example 6 In forming the backcoat layer in Example 4, the coating speed of the coating material for the backcoat layer was 70 m / min to 150 m / min.
A magnetic tape was produced in the same manner as in Example 4 except that the magnetic tape was changed to m / min.
【００２３】実施例７ 実施例１におけるバックコ−ト層の形成において、スム
−ジング処理曲面の曲率半径が２ｍｍ、表面粗さが中心
線平均粗さＲａで 0.008μｍのスム−ザに代えて、スム
−ジング処理曲面の曲率半径が 0.5ｍｍ、表面粗さが中
心線平均粗さＲａで 0.008μｍのスム−ザを使用し、バ
ックコ−ト層用塗料の塗布速度を７０ｍ／min から１０
０ｍ／min に変更した以外は、実施例１と同様にしてス
ム−ジングを行い、磁気テ−プを作製した。Example 7 In the formation of the backcoat layer in Example 1, instead of a smoother having a radius of curvature of 2 mm and a surface roughness of 0.008 .mu.m as a center line average roughness Ra of the smoothing treated curved surface, Using a smoother having a radius of curvature of 0.5 mm and a surface roughness of center line average roughness Ra of 0.008 μm, the coating speed of the coating material for the backcoat layer is from 70 m / min to 10 m / min.
A magnetic tape was prepared by performing smoothing in the same manner as in Example 1 except that the magnetic tape was changed to 0 m / min.
【００２４】実施例８ 実施例１におけるバックコ−ト層の形成において、スム
−ジング処理曲面の曲率半径が２ｍｍ、表面粗さが中心
線平均粗さＲａで 0.008μｍのスム−ザに代えて、スム
−ジング処理曲面の曲率半径が２０ｍｍ、表面粗さが中
心線平均粗さＲａで 0.005μｍのスム−ザを使用し、バ
ックコ−ト層用塗料の塗布速度を７０ｍ／min から１０
０ｍ／min に変更した以外は、実施例１と同様にしてス
ム−ジングを行い、磁気テ−プを作製した。Example 8 In the formation of the back coat layer in Example 1, instead of a smoother having a radius of curvature of 2 mm and a surface roughness of the center line average roughness Ra of 0.008 μm in the smoothing treatment curved surface, The smoothing surface has a radius of curvature of 20 mm and a surface roughness of 0.005 μm with a center line average roughness Ra of 0.005 μm, and the coating speed of the back coat layer coating material is 70 m / min to 10 m / min.
A magnetic tape was prepared by performing smoothing in the same manner as in Example 1 except that the magnetic tape was changed to 0 m / min.
【００２５】実施例９ 実施例１におけるバックコ−ト層の形成において、スム
−ジング処理曲面の曲率半径が２ｍｍ、表面粗さが中心
線平均粗さＲａで 0.008μｍのスム−ザに代えて、スム
−ジング処理曲面の曲率半径が５ｍｍ、表面粗さが中心
線平均粗さＲａで0.02μｍのスム−ザを使用し、バック
コ−ト層用塗料の塗布速度を７０ｍ／min から１００ｍ
／min に変更した以外は、実施例１と同様にしてスム−
ジングを行い、磁気テ−プを作製した。Example 9 In the formation of the back coat layer in Example 1, instead of a smoother having a radius of curvature of 2 mm and a surface roughness of 0.008 .mu.m with a center line average roughness Ra of the smoothing treated curved surface, Using a smoother having a radius of curvature of 5 mm and a surface roughness of 0.02 μm in terms of centerline average roughness Ra, the coating speed of the backcoat layer coating material is 70 m / min to 100 m.
The same as in Example 1 except that the speed was changed to / min.
A magnetic tape was prepared by aging.
【００２６】実施例１０ 実施例１におけるバックコ−ト層の形成において、バッ
クコ−ト層組成物の混合分散時間を７２時間から２４時
間に変更して、バックコ−ト層用塗料を調製し、スム−
ジング処理曲面の曲率半径が２ｍｍ、表面粗さが中心線
平均粗さＲａで0.008μｍのスム−ザに代えて、スム−
ジング処理曲面の曲率半径が５ｍｍ、表面粗さが中心線
平均粗さＲａで 0.005μｍのスム−ザを使用し、バック
コ−ト層用塗料の塗布速度を７０ｍ／min から１００ｍ
／min に変更した以外は、実施例１と同様にしてスム−
ジングを行い、磁気テ−プを作製した。Example 10 In the formation of the backcoat layer in Example 1, the mixing and dispersing time of the backcoat layer composition was changed from 72 hours to 24 hours to prepare a coating material for the backcoat layer. −
Instead of a smoother having a radius of curvature of 2 mm and a surface roughness of the center line average roughness Ra of 0.008 μm
Using a smoother having a radius of curvature of 5 mm and a center line average roughness Ra of 0.005 μm, the coating speed of the backcoat layer coating material is 70 m / min to 100 m.
The same as in Example 1 except that the speed was changed to / min.
A magnetic tape was prepared by aging.
【００２７】比較例１ 実施例１におけるバックコ−ト層の形成において、スム
−ジング処理曲面の曲率半径が２ｍｍ、表面粗さが中心
線平均粗さＲａで 0.008μｍのスム−ザに代えて、エッ
ジの曲率半径が0.05ｍｍのエッジスム−ザを使用した以
外は、実施例１と同様にしてスム−ジングを行い、磁気
テ−プを作製した。Comparative Example 1 In the formation of the back coat layer in Example 1, a smoother having a curvature radius of 2 mm and a surface roughness of 0.008 μm in terms of center line average roughness Ra was used instead of the smoother. A magnetic tape was produced by performing smoothing in the same manner as in Example 1 except that an edge smoother having an edge curvature radius of 0.05 mm was used.
【００２８】比較例２ 比較例１におけるバックコ−ト層の形成において、バッ
クコ−ト層用塗料の塗布速度を７０ｍ／min から１００
ｍ／min に変更した以外は、比較例１と同様にしてスム
−ジングを行い、磁気テ−プを作製した。Comparative Example 2 In the formation of the backcoat layer in Comparative Example 1, the coating speed of the coating material for the backcoat layer was 70 m / min to 100.
Smoothing was performed in the same manner as in Comparative Example 1 except that m / min was changed to prepare a magnetic tape.
【００２９】比較例３ 比較例１におけるバックコ−ト層の形成において、バッ
クコ−ト層用塗料の塗布速度を７０ｍ／min から１５０
ｍ／min に変更した以外は、比較例１と同様にしてスム
−ジングを行い、磁気テ−プを作製した。Comparative Example 3 In the formation of the back coat layer in Comparative Example 1, the coating speed of the coating material for the back coat layer was 70 m / min to 150 m / min.
Smoothing was performed in the same manner as in Comparative Example 1 except that m / min was changed to prepare a magnetic tape.
【００３０】各実施例で得られた磁気テ−プについて、
バックコ−ト層表面に形成された連続した凸状の筋の高
さおよび間隔をＷＹＫＯ社製；ＴＯＰＯ−３Ｄおよび光
学顕微鏡で測定した。また、凸状の筋間部の表面粗さを
東京精密社製；触針式粗さ計サ−フコム（触針先端曲率
半径１μｍ、針圧１０ｍｇ、カットオフ0.08μｍ）で測
定した。下記表１はその結果である。Regarding the magnetic tapes obtained in the respective examples,
The height and interval of continuous convex streaks formed on the surface of the back coat layer were measured by WYKO; TOPO-3D and an optical microscope. In addition, the surface roughness of the convex interstitial area was measured by a contact type roughness meter Surfcom (a stylus tip curvature radius 1 μm, a needle pressure 10 mg, a cutoff 0.08 μm) manufactured by Tokyo Seimitsu Co., Ltd. Table 1 below shows the results.
【００３１】 [0031]
【００３２】また、各実施例および比較例で得られた磁
気テ−プについて、バックコ−ト層表面の摩擦係数、ジ
ッタ−およびガイドロ−ラの汚れを下記の方法で試験測
定した。Further, with respect to the magnetic tapes obtained in the respective examples and comparative examples, the friction coefficient on the surface of the back coat layer, the jitter and the dirt on the guide roller were tested and measured by the following methods.
【００３３】＜摩擦係数＞直径４ｍｍのステンレス（Ｓ
ＵＳ３０４）製円筒（表面粗さ 0.2Ｓ）に磁気テ−プを
バックコ−ト層表面が当接するよう角度９０°で掛け、
その一端に２０ｇの荷重を印加して他端を 1.4cm/secの
速さで往復１００回引っ張った時の荷重により求めた。<Frictional coefficient> Stainless steel with a diameter of 4 mm (S
US304) Cylinder (surface roughness 0.2S) is applied with a magnetic tape at an angle of 90 ° so that the backcoat layer surface abuts,
It was determined by applying a load of 20 g to one end and pulling the other end 100 times back and forth at a speed of 1.4 cm / sec.
【００３４】＜ジッタ−＞磁気テ−プをビデオデッキに
装填して、ビデオ信号を記録再生し、その再生信号の 1
5.75ＫＨz の水平同期信号の間隔を読み取り、その時の
１秒間の水平同期信号のずれの最大値をジッタ−メ−タ
で測定し、その値をジッタ−とした。<Jitter> A magnetic tape is loaded into a VCR, a video signal is recorded and reproduced, and the reproduced signal
The interval of the horizontal synchronizing signal of 5.75 KHz was read, and the maximum value of the deviation of the horizontal synchronizing signal for 1 second at that time was measured by the jitter meter, and the value was taken as the jitter.
【００３５】＜ガイドロ−ラの汚れ＞磁気テ−プをビデ
オデッキに装填して、１００時間連続走行した後のガイ
ドロ−ラを光学顕微鏡で観察し、汚れの無い場合を
（○）、僅かに認められる場合を（△）、汚れの激しい
場合を（×）とした。下記表２はその結果である。<Dirt of Guide Roller> A magnetic tape was loaded on a video deck, and the guide roller after 100 hours of continuous running was observed with an optical microscope. The case where it was recognized was (△), and the case where it was heavily stained was (×). Table 2 below shows the results.
【００３６】 [0036]
【００３７】[0037]
【発明の効果】上記表１および２から明らかなように、
この発明で得られた磁気テ−プ（実施例１〜１０）は、
いずれも比較例１ないし３で得られた磁気テ−プに比
し、バックコ−ト層表面の摩擦係数が小さくて、ジッタ
−が小さく、さらにガイドロ−ラの汚れもないものが多
く、特に実施例１〜６で得られた磁気テ−プは、バック
コ−ト層表面の摩擦係数およびジッタ−が小さくて、ガ
イドロ−ラの汚れがなく、このことからこの発明で得ら
れる磁気記録媒体は、バックコ−ト層表面の摩擦係数が
充分に小さくて、走行安定性に優れていることがわか
る。As is apparent from Tables 1 and 2 above,
The magnetic tapes obtained in the present invention (Examples 1 to 10) are
Compared with the magnetic tapes obtained in Comparative Examples 1 to 3, in many cases, the friction coefficient of the surface of the back coat layer was small, the jitter was small, and the guide rollers were not contaminated. The magnetic tapes obtained in Examples 1 to 6 had a small friction coefficient and jitter on the surface of the back coat layer and did not stain the guide roller. From this, the magnetic recording media obtained by the present invention were It can be seen that the friction coefficient on the surface of the back coat layer is sufficiently small and the running stability is excellent.
Claims (7)
行方向に連続した凸状の筋を表面に有するバックコ−ト
層を設けたことを特徴とする磁気記録媒体1. A magnetic recording medium comprising a substrate having a magnetic layer on the front surface thereof, and a back coat layer having on the back surface thereof convex convex stripes continuous in the running direction.
０〜３０ｎｍである請求項１記載の磁気記録媒体2. The height of a convex streak continuous in the traveling direction is 1
The magnetic recording medium according to claim 1, which has a thickness of 0 to 30 nm.
５０〜５００μｍである請求項１記載の磁気記録媒体3. The interval between convex streaks continuous in the traveling direction is 1
The magnetic recording medium according to claim 1, having a thickness of 50 to 500 μm.
さが中心線平均粗さＲａで 0.015μｍ以下である請求項
１記載の磁気記録媒体4. The magnetic recording medium according to claim 1, wherein the surface roughness between convex streaks continuous in the running direction is 0.015 μm or less in terms of center line average roughness Ra.
の裏面にバックコ−ト層用塗料を塗布し、この塗布によ
り形成されたバックコ−ト層塗膜面をスム−ザのスム−
ジング処理曲面でスム−ジングして、走行方向に連続し
た凸状の筋を表面に有するバックコ−ト層を形成するこ
とを特徴とする磁気記録媒体の製造方法5. A magnetic layer is formed on the surface of a substrate, a backcoat layer coating material is applied to the back surface of the substrate, and the coating surface of the backcoat layer formed by this application is smoothed by a smoother.
A method for manufacturing a magnetic recording medium, characterized in that a backcoat layer having a convex streak continuous in the traveling direction on the surface is formed by smoothing on a curved surface.
半径が１〜１０ｍｍである請求項５記載の磁気記録媒体
の製造方法6. The method of manufacturing a magnetic recording medium according to claim 5, wherein the smoothing surface of the smoother has a radius of curvature of 1 to 10 mm.
粗さが中心線平均粗さＲａで0.01μｍ以下である請求項
５記載の磁気記録媒体の製造方法7. The method for manufacturing a magnetic recording medium according to claim 5, wherein the surface roughness of the smoothing surface of the smoother is 0.01 μm or less in terms of center line average roughness Ra.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23734891A JP3357921B2 (en) | 1991-08-23 | 1991-08-23 | Magnetic recording media |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23734891A JP3357921B2 (en) | 1991-08-23 | 1991-08-23 | Magnetic recording media |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2000308838A Division JP3390918B2 (en) | 2000-10-10 | 2000-10-10 | Magnetic recording media |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0554366A true JPH0554366A (en) | 1993-03-05 |
| JP3357921B2 JP3357921B2 (en) | 2002-12-16 |
Family
ID=17014062
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23734891A Expired - Lifetime JP3357921B2 (en) | 1991-08-23 | 1991-08-23 | Magnetic recording media |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3357921B2 (en) |
-
1991
- 1991-08-23 JP JP23734891A patent/JP3357921B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JP3357921B2 (en) | 2002-12-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2000030237A (en) | Magnetic recording medium and its production | |
| JPH0481256B2 (en) | ||
| US5354610A (en) | Magnetic recording medium comprising a conductive underlayer containing carbon black and a magnetic layer containing tabular barium ferrite magnetic particles, α alumina, and binder resin | |
| JP3882180B2 (en) | Magnetic recording medium and method for manufacturing the same | |
| JPH0362311A (en) | Magnetic recording medium | |
| JPH0479054B2 (en) | ||
| JPH0373415A (en) | Magnetic recording medium | |
| JPH0690782B2 (en) | Magnetic recording medium and manufacturing method thereof | |
| JP3390918B2 (en) | Magnetic recording media | |
| JPH0554366A (en) | Magnetic recording medium and production thereof | |
| JPH0935245A (en) | Magnetic recording medium | |
| JPH1131319A (en) | Magnetic recording medium | |
| JP3384823B2 (en) | Magnetic recording media | |
| JP2821054B2 (en) | Magnetic recording medium and magnetic tape cassette loaded with the magnetic recording medium | |
| JP2781004B2 (en) | Magnetic recording media | |
| JP2789129B2 (en) | Magnetic recording media | |
| JP3012190B2 (en) | Magnetic recording media | |
| JP2860598B2 (en) | Magnetic recording media | |
| JP2000067426A (en) | Magnetic recording medium | |
| JPH04302818A (en) | Magnetic recording medium | |
| JPH1186267A (en) | Magnetic recording medium | |
| JPH09171618A (en) | Production of magnetic recording medium | |
| JPH01112520A (en) | Magnetic recording medium | |
| JPH09297912A (en) | Magnetic recording medium | |
| JPH0349032A (en) | Magnetic recording medium |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20010404 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081011 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091011 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091011 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091011 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101011 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101011 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111011 Year of fee payment: 9 |
|
| EXPY | Cancellation because of completion of term |