JPH07326044A - Magnetic tape - Google Patents
Magnetic tapeInfo
- Publication number
- JPH07326044A JPH07326044A JP6118703A JP11870394A JPH07326044A JP H07326044 A JPH07326044 A JP H07326044A JP 6118703 A JP6118703 A JP 6118703A JP 11870394 A JP11870394 A JP 11870394A JP H07326044 A JPH07326044 A JP H07326044A
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- JP
- Japan
- Prior art keywords
- layer
- magnetic tape
- magnetic
- particles
- thickness
- 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
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、磁気テープに関する。FIELD OF THE INVENTION The present invention relates to a magnetic tape.
【０００２】[0002]
【従来の技術】磁気テープとしては、ポリエチレン−
２，６−ナフタレンジカルボキシレート（以下ＰＥＮと
記載）フィルムを用いた磁気記録媒体が知られている
（例えば特開６２−２２２３５号公報）。また、磁気記
録媒体用フィルムとしては積層厚みと含有粒子粒径の関
係を規定したフィルムが知られている（例えば特開平２
−７７４３１号公報）。2. Description of the Related Art Polyethylene is used as a magnetic tape.
A magnetic recording medium using a 2,6-naphthalene dicarboxylate (hereinafter referred to as PEN) film is known (for example, Japanese Patent Laid-Open No. 62-22235). Also, as a film for a magnetic recording medium, a film is known in which the relationship between the laminated thickness and the particle diameter of the contained particles is defined (for example, Japanese Patent Laid-Open No. HEI-2).
-77431).
【０００３】しかし上記従来の磁気記録媒体、特に磁気
記録媒体用フィルムでは積層厚みと含有粒子粒径の関係
を規定してフィルム表面突起高さの均一化をはかり、磁
気記録媒体としての電磁変換特性とベ−スフィルム表面
の耐摩耗性が向上したが、さらなる高密度磁気記録媒体
とした場合に、テープ化した後の縦方向および横方向の
強度についてより高強度が求められるようになってきて
おり、該用途においては出力特性が不足するという問題
が生じてきている。本発明はかかる課題を解決し、特に
出力特性に優れる磁気テープを提供することを目的とす
る。However, in the above-mentioned conventional magnetic recording media, particularly films for magnetic recording media, the relationship between the laminated thickness and the particle size of the contained particles is defined to make the height of protrusions on the film uniform, and electromagnetic conversion characteristics as a magnetic recording medium are obtained. The wear resistance of the base film surface is improved, but when a higher density magnetic recording medium is used, higher strength is required for the strength in the longitudinal direction and the lateral direction after tape formation. However, there is a problem that the output characteristics are insufficient in the application. An object of the present invention is to solve such problems and to provide a magnetic tape having excellent output characteristics.
【０００４】[0004]
【課題を解決するための手段】この目的に沿う本発明の
磁気テープは、ポリエステルからなる基体フィルムの少
なくとも片面に磁性層を有する磁気テープであって、該
磁性層が２層以上の重層塗布型からなり、テープ縦方向
と横方向のヤング率の差（横−縦）が２００〜１５００
ｋｇ／ｍｍ2 、体積記録密度が５０μｍ3 ／ｂｉｔ以下
であることを特徴とする。The magnetic tape of the present invention which meets this object is a magnetic tape having a magnetic layer on at least one side of a base film made of polyester, wherein the magnetic layer is a multilayer coating type having two or more layers. And the difference in Young's modulus between the longitudinal and lateral directions of the tape (horizontal-vertical) is 200 to 1500.
It is characterized in that it has a volume recording density of 50 μm 3 / bit or less in kg / mm 2 .
【０００５】本発明の磁気テープの基体フィルムはポリ
エステルからなる。ポリエステルとしては特に限定され
ないが、出力特性の点からポリエチレンテレフタレート
（以下ＰＥＴと記載）、ポリエチレン−２，６−ナフタ
レンジカルボキシレート（以下ＰＥＮと記載）を主たる
成分とするのが特に好ましい。主たる成分とは８０％以
上、好ましくは８５％以上の場合をいう。なお、本発明
の目的を阻害しない範囲内で２種以上のポリマを混合し
てもよいし、共重合ポリマを用いてもよい。また、本発
明の目的を阻害しない範囲内で酸化防止剤、熱安定剤、
滑剤、紫外線吸収剤などの添加剤が通常添加される程度
添加されていてもよい。The base film of the magnetic tape of the present invention is made of polyester. The polyester is not particularly limited, but polyethylene terephthalate (hereinafter referred to as PET) and polyethylene-2,6-naphthalene dicarboxylate (hereinafter referred to as PEN) as main components are particularly preferable from the viewpoint of output characteristics. The main component means a case of 80% or more, preferably 85% or more. Two or more kinds of polymers may be mixed, or a copolymerized polymer may be used, as long as the object of the present invention is not impaired. Further, within a range not hindering the object of the present invention, an antioxidant, a heat stabilizer,
Additives such as lubricants and ultraviolet absorbers may be added to the extent that they are usually added.
【０００６】本発明の磁気テープの基体フィルムは特に
限定されないが、出力特性の点からＡ層／Ｂ層の少なく
とも２層構造からなるのが好ましい。Ａ層厚みは特に限
定されないが、出力特性の点から０．０３〜１．０μ
ｍ、好ましくは０．０５〜０．５μｍ、さらに好ましく
は０．０５〜０．３μｍである。積層構成の場合Ａ層／
Ｂ層は、特に限定されないが出力特性の点から、それぞ
れＰＥＮ／ＰＥＴ、ＰＥＮ／ＰＥＮ、ＰＥＴ／ＰＥＮが
好ましく例示される。The base film of the magnetic tape of the present invention is not particularly limited, but it is preferable that it has at least a two-layer structure of A layer / B layer from the viewpoint of output characteristics. The thickness of the layer A is not particularly limited, but from the viewpoint of output characteristics, it is 0.03 to 1.0 μ.
m, preferably 0.05 to 0.5 μm, more preferably 0.05 to 0.3 μm. In case of laminated structure A layer /
The B layer is not particularly limited, but PEN / PET, PEN / PEN, and PET / PEN are preferably exemplified from the viewpoint of output characteristics.
【０００７】本発明の磁気テープの基体フィルムのＡ層
には、特に限定されないが出力特性の点から０．０２〜
１．０μｍ、好ましくは０．０５〜０．５μｍ、さらに
好ましくは０．１〜０．３μｍの粒径の粒子を０．０１
〜３．０重量％、好ましくは０．０２〜２．０重量％、
さらに好ましくは０．１〜１．０重量％含有するのが好
ましい。粒子としては特に限定されないが、出力特性の
点から有機粒子、なかでも架橋型有機粒子、特にポリジ
ビニルベンゼン粒子が好ましい。ポリジビニルベンゼン
粒子とは、架橋成分としてジビニルベンゼンを主体とす
るものをいう。なかでもジビニルベンゼンが粒子成分の
５１％以上、好ましくは６０％以上、さらに好ましくは
７５％以上のものが好ましい。他の成分としては、特に
限定されないが、例えばエチルビニルベンゼン、ジエチ
ルベンゼン等の架橋しない成分があげられる。また、シ
リコーン粒子も好ましく例示される。シリコーン粒子と
は２次元的に架橋されたオルガノポリシロキサン（ＣＨ
3 Ｓi Ｏ3/2 ）を主たる成分とするものが好ましい。そ
の他粒子として、結晶形がα型、γ型、δ型、θ型、η
型のアルミナ、ジルコニア、シリカ、チタン等の凝集粒
子、または、炭酸カルシウム、コロイダルシリカ、チタ
ン等もポリマ中での適切な粒子分散により用いることも
可能である。これらの粒子を複数併用して用いてもよ
い。The layer A of the base film of the magnetic tape of the present invention is not particularly limited, but is 0.02 to 0.02 in terms of output characteristics.
Particles having a particle size of 1.0 μm, preferably 0.05 to 0.5 μm, and more preferably 0.1 to 0.3 μm are 0.01
~ 3.0 wt%, preferably 0.02-2.0 wt%,
More preferably, the content is 0.1 to 1.0% by weight. The particles are not particularly limited, but organic particles, particularly crosslinked organic particles, and particularly polydivinylbenzene particles are preferable from the viewpoint of output characteristics. The polydivinylbenzene particles are mainly composed of divinylbenzene as a crosslinking component. Among them, divinylbenzene is preferably at least 51%, preferably at least 60%, more preferably at least 75% of the particle component. Other components are not particularly limited, and examples thereof include non-crosslinking components such as ethylvinylbenzene and diethylbenzene. Further, silicone particles are also preferably exemplified. Silicone particles are two-dimensionally cross-linked organopolysiloxane (CH
Those containing 3 Si 2 O 3/2 ) as a main component are preferable. As other particles, the crystal form is α type, γ type, δ type, θ type, η
Agglomerated particles of type alumina, zirconia, silica, titanium, etc., or calcium carbonate, colloidal silica, titanium, etc. can also be used by appropriate particle dispersion in the polymer. A plurality of these particles may be used in combination.
【０００８】Ａ層厚みｔとＡ層に含有する粒子粒径ｄの
関係は特に限定されないが、０．２ｄ≦ｔ≦１０ｄ、好
ましくは０．５ｄ≦ｔ≦５ｄ、さらに好ましくは０．５
ｄ≦ｔ≦３ｄの場合に、特に出力特性が良好となる。The relationship between the thickness t of the A layer and the particle diameter d of the particles contained in the A layer is not particularly limited, but 0.2d≤t≤10d, preferably 0.5d≤t≤5d, more preferably 0.5.
When d ≦ t ≦ 3d, the output characteristics are particularly good.
【０００９】Ａ層以外のフィルム層、つまりＢ層等を構
成するポリマ中に粒子を含有していてもかまわない。こ
の場合、粒径は０．０５〜１．０μｍ、好ましくは０．
１〜０．５μｍ、含有量は０．０５〜１．０重量％であ
る炭酸カルシウム、アルミナ、シリカ、チタン、有機粒
子、カーボンブラック等から選ばれる粒子を含有するの
が好ましい。Particles may be contained in the polymer constituting the film layers other than the A layer, that is, the B layer and the like. In this case, the particle size is 0.05 to 1.0 μm, preferably 0.1.
It is preferable to contain particles selected from calcium carbonate, alumina, silica, titanium, organic particles, carbon black and the like having a content of 1 to 0.5 μm and a content of 0.05 to 1.0% by weight.
【００１０】本発明の磁気テープの基体フィルムは、上
記組成物を二軸配向したフィルムである。一軸あるいは
無配向フィルムでは幅方向強度が不足するので好ましく
ない。基体フィルムは、フィルムの厚さ方向の一部分、
例えば表層付近のポリマ分子の配向が無配向、あるいは
一軸配向になっていない、すなわち厚さ方向の全部分の
分子配向が二軸配向である場合に出力特性がより一層良
好となる。特にアッベ屈折率計、レーザーを用いた屈折
率計、全反射レーザーラマン法などによって測定される
分子配向が、表面、裏面ともに二軸配向である場合に出
力特性がより一層良好となる。The base film of the magnetic tape of the present invention is a film in which the above composition is biaxially oriented. A uniaxial or non-oriented film is not preferable because it lacks strength in the width direction. The base film is a part in the thickness direction of the film,
For example, when the orientation of polymer molecules near the surface layer is non-orientated, or not uniaxially oriented, that is, when the molecular orientations of all parts in the thickness direction are biaxially oriented, the output characteristics are further improved. In particular, when the molecular orientation measured by an Abbe refractometer, a refractometer using a laser, a total reflection laser Raman method or the like is biaxial orientation on both the front surface and the back surface, the output characteristics are further improved.
【００１１】本発明の磁気テープは上記基体フィルムの
少なくとも片面に、出力特性の点から２層以上の重層塗
布型磁性層を設ける。In the magnetic tape of the present invention, two or more multi-layer coating type magnetic layers are provided on at least one surface of the above base film from the viewpoint of output characteristics.
【００１２】重層塗布型磁性層の上層としては、磁性粉
をバインダー樹脂中に分散せしめてなる。磁性粉はＦ
ｅ、Ｃｏ、Ｆｅ−Ａｌ等の強磁性金属粉末および／また
はバリウムフェライト等の六方晶系磁性粉が好ましく例
示される。上層磁性層の層厚みは０．１〜１μｍ、好ま
しくは０．１〜０．５μｍである。As the upper layer of the multi-layer coating type magnetic layer, magnetic powder is dispersed in a binder resin. Magnetic powder is F
Preferred examples include ferromagnetic metal powders such as e, Co and Fe-Al and / or hexagonal magnetic powders such as barium ferrite. The layer thickness of the upper magnetic layer is 0.1 to 1 μm, preferably 0.1 to 0.5 μm.
【００１３】重層塗布型磁性層の下層としては、磁性粉
及び／又は非磁性粉が含有される。磁性粉としてはγ−
酸化鉄、Ｃｏ含有γ−酸化鉄等が好ましく例示される。
非磁性粉としては、酸化チタン、カーボンブラック等が
好ましく例示される。非磁性粉の平均粒径としては１〜
５００ｎｍ、好ましくは１〜３００ｎｍである。下層磁
性層の層厚みは０．１〜３μｍ、このましくは０．１〜
２μｍである。バインダーとしては例えばポリウレタ
ン、ポリエステル、塩化ビニル系共重合体等が好ましく
例示される。The lower layer of the multi-layer coating type magnetic layer contains magnetic powder and / or non-magnetic powder. Γ- for magnetic powder
Preferable examples include iron oxide and Co-containing γ-iron oxide.
Preferable examples of the non-magnetic powder include titanium oxide and carbon black. The average particle size of the non-magnetic powder is 1 to
It is 500 nm, preferably 1 to 300 nm. The lower magnetic layer has a layer thickness of 0.1 to 3 μm, preferably 0.1 to 3 μm.
2 μm. Preferable examples of the binder include polyurethane, polyester, and vinyl chloride copolymer.
【００１４】本発明の磁気テープの縦方向と横方向のヤ
ング率の差（横−縦）は出力特性の点から２００〜１５
００ｋｇ／ｍｍ2 、好ましくは３００〜１３００ｋｇ／
ｍｍ2 である。The difference in the Young's modulus between the longitudinal direction and the lateral direction (horizontal-longitudinal) of the magnetic tape of the present invention is 200 to 15 from the viewpoint of output characteristics.
00 kg / mm 2 , preferably 300 to 1300 kg /
mm 2 .
【００１５】さらに、本発明の磁気テープは体積記録密
度が出力特性の点から５０μｍ3 ／ｂｉｔ以下、好まし
くは３０μｍ3 ／ｂｉｔ以下、さらに好ましくは２５μ
ｍ3／ｂｉｔ以下、最も好ましくは１５μｍ3 ／ｂｉｔ
以下である。Further, the magnetic tape of the present invention has a volume recording density of 50 μm 3 / bit or less, preferably 30 μm 3 / bit or less, more preferably 25 μm from the viewpoint of output characteristics.
m 3 / bit or less, most preferably 15 μm 3 / bit
It is the following.
【００１６】また、必要に応じて反対面にバックコート
層を有することが好ましい。Further, it is preferable to have a back coat layer on the opposite surface, if necessary.
【００１７】本発明の磁気テープはデジタル用磁気テー
プとして特に好ましく用いられる。さらに特に高出力が
要求されるＨＤＴＶ（ハイディフィニションテレビジョ
ン、ＮＨＫのハイビジョン等）用磁気テープとして好ま
しく用いられる。The magnetic tape of the present invention is particularly preferably used as a digital magnetic tape. Further, it is preferably used as a magnetic tape for HDTV (high definition television, high definition of NHK, etc.) which requires particularly high output.
【００１８】また、本発明の磁気テープはコンピュータ
用等のデータストレージ用にも好ましく用いられる。The magnetic tape of the present invention is also preferably used for data storage such as computers.
【００１９】また、本発明の磁気テープは放送局での撮
影、編集やスタジオ撮影、編集、販売用、または各種披
露宴等での業務用として、特に好ましく用いられる。Further, the magnetic tape of the present invention is particularly preferably used for shooting at a broadcasting station, editing, studio shooting, editing, sales, or for commercial use at various receptions.
【００２０】次に本発明の磁気テープの好ましい製造方
法を以下に示し説明するが、これに限定されるものでは
ない。Next, a preferred method for producing the magnetic tape of the present invention will be shown and described below, but the present invention is not limited thereto.
【００２１】まず磁気テープを構成する基体フィルムの
好ましい製造方法として、ポリエステルに粒子を含有せ
しめる方法としては、ジオ−ル成分であるエチレングリ
コールにスラリーの形で分散させ、このエチレングリコ
ールを所定のジカルボン酸成分と重合するのが好まし
い。また粒子の水スラリーを直接所定のポリエステルペ
レットと混合し、ベント式２軸混練押出機を用いて練り
込む方法は、本発明の効果をより一層良好とするのに有
効である。First, as a preferred method for producing a base film constituting a magnetic tape, in which particles are contained in polyester, ethylene glycol, which is a diol component, is dispersed in the form of a slurry, and this ethylene glycol is mixed with a predetermined dicarboxylic acid. It is preferably polymerized with an acid component. Further, a method in which an aqueous slurry of particles is directly mixed with a predetermined polyester pellet and kneaded by using a vent type twin-screw kneading extruder is effective for further improving the effect of the present invention.
【００２２】粒子の含有量を調節する方法としては、上
記方法で高濃度マスターを作っておき、それを製膜時に
粒子を実質的に含有しないポリマで希釈して粒子の含有
量を調節する方法が有効である。As a method for controlling the content of particles, a high-concentration master is prepared by the above-mentioned method, and it is diluted with a polymer containing substantially no particles at the time of film formation to control the content of particles. Is effective.
【００２３】次に、粒子を所定量含有するペレットを必
要に応じて乾燥したのち、公知の溶融積層用押出機に供
給し、スリット状のダイからシ−ト状に押出し、キャス
ティングロ−ル上で冷却固化せしめて未延伸フィルムを
作る。すなわち複数の押出し機、複数のマニホ−ルドま
たは合流ブロックを用いて溶融状態のポリエステルを積
層する。この場合、粒子を含有するポリマ流路にスタテ
ィックミキサー、ギヤポンプを設置する方法は本発明の
効果をより一層良好とするのに有効である。Next, pellets containing a predetermined amount of particles are dried, if necessary, and then fed to a known extruder for melt lamination, extruded in a sheet form from a slit die, and cast on a casting roll. It is cooled and solidified with to make an unstretched film. That is, the polyester in a molten state is laminated using a plurality of extruders, a plurality of manifolds or a merging block. In this case, the method of installing the static mixer and the gear pump in the polymer channel containing the particles is effective for further improving the effect of the present invention.
【００２４】次にこの未延伸フィルムを二軸延伸し、二
軸配向させる。延伸方法としては、逐次二軸延伸法また
は同時二軸延伸法を用いることができる。ただし、最初
に長手方向、次に幅方向の延伸を行なう逐次二軸延伸法
を用い、長手方向の延伸を３段階以上に分けて、縦延伸
温度８０〜１８０℃、総縦延伸倍率３．０〜６．０倍、
縦延伸速度5,000 〜50,000％／分の範囲で行なうのが好
ましい。幅方向の延伸方法としてはテンタ−を用いる方
法が好ましく、延伸温度８０〜１８０℃、幅方向延伸倍
率は縦倍率より大きく４．０〜７．０倍、好ましくは
５．０〜６．５倍、幅方向の延伸速度1,000 〜20,000％
／分の範囲で行なうのが好ましい。さらに必要に応じ
て、再縦延伸、再横延伸を行なう。その場合の延伸条件
としては長手方向の延伸は９０〜１８０℃、延伸倍率
１．１〜２．０倍、幅方向の延伸方法としてはテンタ−
を用いる方法が好ましく、延伸温度９０〜１８０℃、幅
方向延伸倍率は１．１〜２．０で行なうのが好ましい。Next, this unstretched film is biaxially stretched and biaxially oriented. As a stretching method, a sequential biaxial stretching method or a simultaneous biaxial stretching method can be used. However, using a sequential biaxial stretching method in which stretching is first performed in the longitudinal direction and then in the width direction, the stretching in the longitudinal direction is divided into three or more stages, and the longitudinal stretching temperature is 80 to 180 ° C. and the total longitudinal stretching ratio is 3.0. ~ 6.0 times,
It is preferable to carry out at a longitudinal stretching speed of 5,000 to 50,000% / min. As a stretching method in the width direction, a method using a tenter is preferable, the stretching temperature is 80 to 180 ° C., and the stretching ratio in the width direction is 4.0 to 7.0 times, preferably 5.0 to 6.5 times larger than the longitudinal magnification. , Width stretching speed 1,000-20,000%
It is preferably carried out in the range of / minute. Further, if necessary, longitudinal re-stretching and lateral re-stretching are performed. In that case, as the stretching conditions, the stretching in the longitudinal direction is 90 to 180 ° C., the stretching ratio is 1.1 to 2.0 times, and the stretching method in the width direction is tenter.
Is preferably used, and the stretching temperature is 90 to 180 ° C., and the stretching ratio in the width direction is preferably 1.1 to 2.0.
【００２５】次にこの二軸配向フィルムを熱処理する。
この場合の熱処理温度は１７０〜２２０℃、特に１７０
〜２１０℃で時間は０. ５〜６０秒の範囲が好適であ
る。Next, the biaxially oriented film is heat treated.
The heat treatment temperature in this case is 170 to 220 ° C., especially 170
It is preferred that the time is from 210 ° C to 0.5 to 60 seconds.
【００２６】次に上記フィルムに磁性層を設ける。重層
塗布方法としては、公知の方法を用いることができるが
特に口金塗布方式（ダイコーター）を用いるのが好まし
い。また、カレンダー工程は、ポリアミドまたはポリエ
ステルを弾性ロールに用い、２５〜９０℃、特に４０〜
７０℃の温度範囲で行なうのが本発明の磁気テープを得
るのに有効である。さらに、このフィルムの磁性層をキ
ュアした後、その原反（広幅）をスリットして本発明の
磁気テープを得る。Next, a magnetic layer is provided on the above film. As the multi-layer coating method, a known method can be used, but it is particularly preferable to use a die coating method (die coater). In the calendering step, polyamide or polyester is used for the elastic roll, and the temperature is 25 to 90 ° C., especially 40 to 90 ° C.
Performing in the temperature range of 70 ° C. is effective for obtaining the magnetic tape of the present invention. Further, after curing the magnetic layer of this film, the original fabric (wide width) is slit to obtain the magnetic tape of the present invention.
【００２７】［物性の測定方法ならびに効果の評価方
法］本発明の特性値の測定方法並びに効果の評価方法は
次のとおりである。[Physical property measuring method and effect evaluating method] The characteristic value measuring method and effect evaluating method of the present invention are as follows.
【００２８】（１）粒子の平均粒径 フィルム断面を透過型電子顕微鏡（ＴＥＭ）を用い、１
０万倍以上の倍率で観察する。ＴＥＭの切片厚さは約１
００ｎｍとし、場所を変えて１００視野以上測定する。
粒子の平均径は重量平均径（等価円相当径）から求め
る。(1) Average Particle Size of Particles The cross section of the film was measured by using a transmission electron microscope (TEM).
Observe at a magnification of 0,000 times or more. Section thickness of TEM is about 1
It is set to 00 nm, and the location is changed to measure 100 fields or more.
The average diameter of the particles is calculated from the weight average diameter (equivalent circle diameter).
【００２９】（２）粒子の含有量 ポリマは溶解し粒子は溶解させない溶媒を選択し、粒子
をポリマから遠心分離し、粒子の全体重量に対する比率
（重量％）をもって粒子含有量とする。場合によっては
赤外分光法の併用も有効である。(2) Content of Particles A solvent in which a polymer is dissolved but a particle is not dissolved is selected, the particles are centrifuged from the polymer, and the ratio (% by weight) to the total weight of the particles is taken as the particle content. In some cases, the combined use of infrared spectroscopy is also effective.
【００３０】（３）フィルム積層厚み ２次イオン質量分析装置（ＳＩＭＳ）を用いて、表層か
ら深さ３０００ｎｍの範囲のフイルム中の粒子の内もっ
とも高濃度の粒子に起因する元素とポリエステルの炭素
元素の濃度比（Ｍ+ ／Ｃ+ ）を粒子濃度とし、表面から
深さ３０００ｎｍまで厚さ方向の分析を行なう。表層で
は表面という界面のために粒子濃度は低く表面から遠ざ
かるにつれて粒子濃度は高くなる。本発明フイルムの場
合はいったん極大値となった粒子濃度がまた減少し始め
る。この濃度分布曲線をもとに表層粒子濃度がの極大値
の１／２となる深さ（この深さは極大値となる深さより
も深い）を求め、これを積層厚さとした。条件は次の通
り。(3) Film Lamination Thickness Using a secondary ion mass spectrometer (SIMS), the element derived from the highest concentration of particles in the film in the depth range of 3000 nm from the surface layer and the carbon element of polyester The concentration ratio (M + / C + ) is defined as the particle concentration, and analysis is performed in the thickness direction from the surface to a depth of 3000 nm. In the surface layer, the particle concentration is low due to the interface of the surface, and the particle concentration increases as the distance from the surface increases. In the case of the film of the present invention, the particle concentration once reaching the maximum value starts to decrease again. Based on this concentration distribution curve, the depth at which the surface layer particle concentration becomes 1/2 of the maximum value of (the depth is deeper than the maximum value) was determined, and this was taken as the laminated thickness. The conditions are as follows.
【００３１】 測定装置 ２次イオン質量分析装置（ＳＩＭＳ） ***、ATOMIKA 社製 A-DIDA3000 測定条件 １次イオン種 ：Ｏ2 + １次イオン加速電圧：１２KV １次イオン電流：２００nA ラスター領域：４００μｍ□ 分析領域：ゲ−ト３０％ 測定真空度：５．０×１０-9Torr Ｅ−ＧＵＮ：０．５KV−３．０Ａ なお、表層から深さ３０００ｎｍの範囲に最も多く含有
する粒子が有機高分子粒子の場合はＳＩＭＳでは測定が
難しいので、表面からエッチングしながらＸＰＳ（Ｘ線
光電子分光法）、ＩＲ（赤外分光法）などで上記同様の
デプスプロファイルを測定し積層厚さを求めても良い
し、また、電子顕微鏡等による断面観察で粒子濃度の変
化状態やポリマの違いによるコントラストの差から界面
を認識し積層厚さを求めることもできる。さらには、積
層ポリマを剥離後、薄膜段差測定機を用いて測定厚さを
求めることもできる。Measurement device Secondary ion mass spectrometer (SIMS) A-DIDA3000 manufactured by ATOMIKA, West Germany Measurement conditions Primary ion species: O 2 + Primary ion acceleration voltage: 12 KV Primary ion current: 200 nA Raster region: 400 μm □ Analytical area: 30% of gate Measurement degree of vacuum: 5.0 × 10 -9 Torr E-GUN: 0.5 KV-3.0A In addition, the particles contained most in the range from the surface layer to the depth of 3000 nm are organic polymers. In the case of particles, since it is difficult to measure by SIMS, the depth profile similar to the above may be measured by XPS (X-ray photoelectron spectroscopy), IR (infrared spectroscopy) or the like while etching from the surface to obtain the laminated thickness. Alternatively, the layer thickness can be obtained by recognizing the interface from the state of change in particle concentration or the difference in contrast due to the difference in polymer by observing the cross section with an electron microscope or the like. Further, after the laminated polymer is peeled off, the measured thickness can be obtained by using a thin film step measuring machine.
【００３２】（４）フィルム表面の配向 ナトリウムＤ線（５８９ｎｍ）を光源として、アッベ屈
折率計を用いて測定した。マウント液にはヨウ化メチレ
ンを用い、２５℃、６５％ＲＨにて測定した。フィルム
の二軸配向性は長手方向、幅方向、厚さ方向の屈折率を
Ｎ1 、Ｎ2 、Ｎ3 とした時、（Ｎ1 −Ｎ2 ）の絶対値が
０．０７以下、かつ、Ｎ3 ／［（Ｎ1＋Ｎ2 ）／２］が
０．９５以下であることをひとつの基準とできる。ま
た、レーザー型屈折率計を用いて屈折率を測定してもよ
い。さらに、この方法では測定が難しい場合は全反射レ
ーザーラマン法を用いることもできる。(4) Orientation of film surface It was measured using an Abbe refractometer with sodium D line (589 nm) as a light source. Methylene iodide was used as the mount solution, and measurement was performed at 25 ° C. and 65% RH. The biaxial orientation of the film has an absolute value of (N1-N2) of 0.07 or less and N3 / [(N1 + N2 when the refractive indices in the longitudinal direction, the width direction and the thickness direction are N1, N2 and N3. ) / 2] is 0.95 or less as one criterion. Further, the refractive index may be measured using a laser type refractometer. Further, when the measurement is difficult by this method, the total reflection laser Raman method can be used.
【００３３】（５）ヤング率 ＪＩＳ−Ｚ−１７０２に規定された方法にしたがって、
インストロンタイプの引っ張り試験機を用いて、２５
℃、６５％ＲＨにて測定した。(5) Young's modulus According to the method specified in JIS-Z-1702,
25 using an Instron type tensile tester
It was measured at 65 ° C. and 65% RH.
【００３４】（６）体積記録密度 体積記録密度は、単位ｂｉｔを記録するための体積を次
式で定義する。(6) Volume Recording Density The volume recording density defines the volume for recording a unit bit by the following formula.
【００３５】記録波長（μｍ）×トラック幅（μｍ）×
テープ厚み（μｍ） （７）出力特性 市販のＨｉ８ＶＴＲ（ＳＯＮＹ社製ＥＶ−ＢＳ３００
０）を用いて、７ＭＨｚ±１ＭＨｚのＣ／Ｎの測定を行
なった。このＣ／Ｎを市販のＨｉ８用ビデオテープ（１
２０分ＭＥ）と比較して、 ＋３ｄＢ以上 ：優 ＋１〜＋３ｄＢ：良 ＋１ｄＢ未満 ：不良 で判定した。Recording wavelength (μm) × track width (μm) ×
Tape thickness (μm) (7) Output characteristics Commercially available Hi8VTR (EV-BS300 manufactured by Sony Corporation)
0) was used to measure C / N at 7 MHz ± 1 MHz. This C / N is a commercially available video tape for Hi8 (1
Compared with 20 minutes ME), it was judged to be +3 dB or more: excellent, +1 to +3 dB: good, less than +1 dB: poor.
【００３６】[0036]
【実施例】次に実施例に基づき、本発明をさらに詳細に
説明する。The present invention will be described in more detail based on the following examples.
【００３７】実施例１（表１） 粒子組成がジビニルベンゼン８１％であるポリジビニル
ベンゼン粒子の水スラリーをベント式の２軸混練押出機
を用いて直接ＰＥＮに練り込み、ＰＥＮの粒子ペレット
を得た。Example 1 (Table 1) An aqueous slurry of polydivinylbenzene particles having a particle composition of 81% divinylbenzene was directly kneaded into PEN using a vent type twin-screw kneading extruder to obtain PEN particle pellets. It was
【００３８】この粒子ペレットと実質的に粒子を含有し
ないＰＥＮポリマペレットを適当量混合し、１８０℃で
８時間減圧乾燥（３Torr）した後、ポリマＡ：０．３μ
ｍ径ポリジビニルベンゼン粒子１．０重量％含有ポリ
マ、ポリマＢ：０．３μｍ径ポリジビニルベンゼン粒子
０．１重量％含有ポリマをそれぞれ押出機１、押出機２
に供給し２９０℃、２９５℃で溶融した。これらのポリ
マを高精度瀘過した後、矩形合流部にて２層積層とした
（Ａ／Ｂ）。This particle pellet and a PEN polymer pellet containing substantially no particles were mixed in an appropriate amount and dried under reduced pressure (3 Torr) at 180 ° C. for 8 hours, and then polymer A: 0.3 μm
Extruder 1 and Extruder 2 are polymers containing 1.0 wt% of m-diameter polydivinylbenzene particles and polymer B: Polymer containing 0.1 wt% of 0.3 μm-diameter polydivinylbenzene particles, respectively.
And melted at 290 ° C and 295 ° C. After high-precision filtration of these polymers, two layers were laminated at the rectangular junction (A / B).
【００３９】これを静電印加キャスト法を用いて表面温
度２５℃のキャスティング・ドラムに巻きつけて冷却固
化し、未延伸フィルムを作った。この時、口金スリット
間隙／未延伸二軸配向フィルム厚さの比を１０とした。
また、それぞれの押出機の吐出量を調節し総厚さ、およ
びＡ層の厚さを調節した。This was wound around a casting drum having a surface temperature of 25 ° C. by an electrostatically applied cast method and cooled and solidified to prepare an unstretched film. At this time, the ratio of the die slit gap / the unstretched biaxially oriented film thickness was set to 10.
Further, the total thickness and the thickness of the A layer were adjusted by adjusting the discharge amount of each extruder.
【００４０】この未延伸フィルムを温度１３５℃にて長
手方向に４．２５倍延伸した。この延伸は２組ずつのロ
−ルの周速差で、４段階で行なった。この一軸延伸フィ
ルムをテンターを用いて１４０℃で幅方向に５．０倍延
伸した。さらに、テンターを用いて１７０℃で幅方向に
１．５５倍延伸した。このフィルムを定長下で２１０℃
にて３秒間熱処理し、総厚さ４．５μｍ、Ａ層厚さ０．
３μｍの二軸配向フィルムを得た。This unstretched film was stretched 4.25 times in the longitudinal direction at a temperature of 135.degree. This stretching was carried out in four stages with the peripheral speed difference between each pair of two rolls. This uniaxially stretched film was stretched 5.0 times in the width direction at 140 ° C. using a tenter. Further, it was stretched 1.55 times in the width direction at 170 ° C. using a tenter. This film under constant length 210 ℃
Heat treatment for 3 seconds at a total thickness of 4.5 μm and an A layer thickness of 0.
A 3 μm biaxially oriented film was obtained.
【００４１】次にこのフィルムに磁性層をダイコーター
にて塗布した。Next, a magnetic layer was applied to this film with a die coater.
【００４２】 ＜下層用塗料の組成＞ 酸化チタン １００部 スルホン酸金属塩含有塩化ビニル系樹脂 ７部 ＳＯ3 Ｎａ含有ポリエステルポリウレタン樹脂 ４部 シクロヘキサン ３０部 メチルエチルケトン ２０部 トルエン ２０部 上記した塗料成分を混練、分散した。<Composition of paint for lower layer> Titanium oxide 100 parts Vinyl chloride resin containing sulfonic acid metal salt 7 parts SO 3 Na containing polyester polyurethane resin 4 parts Cyclohexane 30 parts Methyl ethyl ketone 20 parts Toluene 20 parts Kneading the above paint components, Dispersed.
【００４３】＜上層用塗料の組成＞ 強磁性合金粉末：Ｆｅ−Ａｌ系Ｆｅ：Ａｌ重量比＝１０
０：５（Ｈｃ：１５８０Ｏｅ、比表面積＝５５ｍ2 ／
ｇ、平均長軸長０．１６μｍ、軸比８、結晶サイズ１７
０オングストローム、σs ：１２０ｅｍｕ／ｇ）または
強磁性板状六方晶系フェライト（Ｈｃ：１０００Ｏｅ、
比表面積＝５５ｍ2 ／ｇ、σs ：６４ｅｍｕ／ｇ、板状
比：４） α−Ａｌ2 Ｏ3 ５部 スルホン酸金属塩含有塩ビ系樹脂 １０部 ＳＯ3 Ｎａ含有ポリエステルポリウレタン樹脂 ５部 カーボンブラック １部 ミリスチン酸 １部 ステアリン酸 １部 ブチルステアレート １部 シクロヘキサン １００部 メチルエチルケトン １００部 トルエン １００部 上記磁性塗料成分を混練分散した後、日本ポリウレタン
工業（株）製のコロネートＬ５部を添加して上層用塗料
とした。<Composition of coating material for upper layer> Ferromagnetic alloy powder: Fe-Al system Fe: Al weight ratio = 10
0: 5 (Hc: 1580 Oe, specific surface area = 55 m 2 /
g, average major axis length 0.16 μm, axial ratio 8, crystal size 17
0 angstrom, σ s : 120 emu / g) or ferromagnetic plate-like hexagonal ferrite (Hc: 1000 Oe,
Specific surface area = 55 m 2 / g, σ s : 64 emu / g, plate ratio: 4) α-Al 2 O 3 5 parts Sulfonic acid metal salt-containing vinyl chloride resin 10 parts SO 3 Na-containing polyester polyurethane resin 5 parts Carbon black 1 part Myristic acid 1 part Stearic acid 1 part Butyl stearate 1 part Cyclohexane 100 parts Methyl ethyl ketone 100 parts Toluene 100 parts After kneading and dispersing the above magnetic coating components, 5 parts of Coronate L manufactured by Nippon Polyurethane Industry Co., Ltd. is added to form an upper layer. It was used as paint.
【００４４】この磁気テープの特性は第１表に示したと
おりであり、出力特性が良好であった。The characteristics of this magnetic tape are as shown in Table 1, and the output characteristics were good.
【００４５】実施例２〜５、比較例１〜２（表１） 実施例１と同様にして、粒子の種類、粒径、含有量、積
層厚み、フィルム強度等を変更した磁気テープを得た。
表１に示すように本発明範囲の磁気テープは出力特性が
良好であるが、そうでないものは出力特性が良好でない
ことがわかる。Examples 2 to 5 and Comparative Examples 1 and 2 (Table 1) In the same manner as in Example 1, magnetic tapes having different kinds of particles, particle size, content, laminated thickness, film strength and the like were obtained. .
As shown in Table 1, it can be seen that the magnetic tapes within the scope of the present invention have good output characteristics, but those that do not have good output characteristics.
【表１】 [Table 1]
【００４６】[0046]
【発明の効果】本発明の磁気テープは縦と横の強度の関
係を特定し、かつ、重層塗布型磁性層を設けたので優れ
た出力特性を得ることができた。また、磁気テープの単
位体積あたりの記録密度を特定したので、今後の長時間
録画にも十分耐え得ることができる。The magnetic tape of the present invention has excellent output characteristics because the relationship between longitudinal strength and lateral strength is specified and the multi-layer coating type magnetic layer is provided. Further, since the recording density per unit volume of the magnetic tape is specified, it is possible to sufficiently endure long-term recording in the future.
Claims (8)
なくとも片面に磁性層を有する磁気テープであって、該
磁性層が２層以上の重層塗布型からなり、テープ縦方向
と横方向のヤング率の差（横−縦）が２００〜１５００
ｋｇ／ｍｍ2、体積記録密度が５０μｍ3 ／ｂｉｔ以下
であることを特徴とする磁気テープ。1. A magnetic tape having a magnetic film on at least one surface of a base film made of polyester, wherein the magnetic layer is a multi-layer coating type having two or more layers, and the difference in Young's modulus between the longitudinal direction and the lateral direction of the tape ( Horizontal-vertical) is 200-1500
A magnetic tape having a volume recording density of 50 μm 3 / bit or less at kg / mm 2 .
ナフタレンジカルボキシレートからなる請求項１記載の
磁気テープ。2. The base film is polyethylene-2,6-
The magnetic tape according to claim 1, which is composed of naphthalene dicarboxylate.
２層構造からなり、Ａ層厚みが０．０３〜１．０μｍで
ある請求項１〜２記載の磁気テープ。3. The magnetic tape according to claim 1, wherein the base film has a structure of at least two layers of A layer / B layer, and the A layer has a thickness of 0.03 to 1.0 μm.
−２，６−ナフタレンジカルボキシレートである請求項
３記載の磁気テープ。4. The magnetic tape according to claim 3, wherein the A layer and / or the B layer is polyethylene-2,6-naphthalenedicarboxylate.
粒子を０．０１〜３．０重量％含有する請求項３〜４記
載の磁気テープ。5. The magnetic tape according to claim 3, wherein the A layer contains 0.01 to 3.0% by weight of particles having an average particle size of 0.02 to 1.0 μm.
層の層厚さｔ（ｎｍ）との関係が０．２ｄ≦ｔ≦１０ｄ
である請求項５記載の磁気テープ。6. The average particle diameter d (nm) of the A layer-containing particles and A
The relationship with the layer thickness t (nm) of the layer is 0.2d ≦ t ≦ 10d
6. The magnetic tape according to claim 5.
１記載の磁気テープ。7. The magnetic tape according to claim 1, which is used in a digital recording type.
１記載の磁気テープ。8. The magnetic tape according to claim 1, which is used for HDTV recording.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6118703A JPH07326044A (en) | 1994-05-31 | 1994-05-31 | Magnetic tape |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6118703A JPH07326044A (en) | 1994-05-31 | 1994-05-31 | Magnetic tape |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07326044A true JPH07326044A (en) | 1995-12-12 |
Family
ID=14743054
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6118703A Pending JPH07326044A (en) | 1994-05-31 | 1994-05-31 | Magnetic tape |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07326044A (en) |
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| US11417357B2 (en) | 2018-07-27 | 2022-08-16 | Fujifilm Corporation | Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus |
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-
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