JPS61167531A - Polyester film for magnetic sheet - Google Patents

Polyester film for magnetic sheet

Info

Publication number
JPS61167531A
JPS61167531A JP741585A JP741585A JPS61167531A JP S61167531 A JPS61167531 A JP S61167531A JP 741585 A JP741585 A JP 741585A JP 741585 A JP741585 A JP 741585A JP S61167531 A JPS61167531 A JP S61167531A
Authority
JP
Japan
Prior art keywords
film
longitudinal direction
polyester
polyester film
stretched
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
Application number
JP741585A
Other languages
Japanese (ja)
Other versions
JPH0425855B2 (en
Inventor
Shigeo Uchiumi
滋夫 内海
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Diafoil Co Ltd
Original Assignee
Diafoil Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Diafoil Co Ltd filed Critical Diafoil Co Ltd
Priority to JP741585A priority Critical patent/JPS61167531A/en
Publication of JPS61167531A publication Critical patent/JPS61167531A/en
Publication of JPH0425855B2 publication Critical patent/JPH0425855B2/ja
Granted legal-status Critical Current

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  • Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

PURPOSE:To obtain the titled film which is superior in flat and easily sliding properties, by a method wherein a difference between a shrinkage factor in a longitudinal direction and that in a widthward direction at a nonreversible process under specific terms satisfies a specific expression, in the film wherein R to be obtained through polarized light and fluorescent strength of a polyester film is shown by a specific expression. CONSTITUTION:A polyester raw material containing particles is dried by a conventional device, melted and extruded through an extruding machine and unoriented polyester sheet is molded by cooling and curing. The same is oriented in a longitudinal direction and after orientation further in the longitudinal direction the same is oriented in a crosswise direction in the next place, reoriented longitudinally so that 0.95<=R(45 deg.)<=1.05 is given again in the longitudinal direction and then fixed thermally according to necessity. Then calendering treatment is applied to said film for 72hr under terms of the temperature of 53 deg.C and the humidity of 90% and a target film whose difference between a shrinkage factor alphaMD in the longitudinal direction and that alphaTD in a widthward direction at a nonreversible process is shown by an expression is obtained. EFFECT:The titled sheet is superior in anisotropy within the surface, the anisotropy within the surface of a dimensional variation at a nonreversible process and flat and easily sliding properties.

Description

【発明の詳細な説明】 産 土の1  野 本発明は平担易滑性に優れ、かつ面内の光学的異方性が
小さく、同時に過酷な温熱処理による寸法変化のフィル
ム面内異方性が小さいフロッピーディスク用及び電子写
真用基体フィルム等磁気シート用フィルムに適した二軸
配向ポリエステルフィルムに関するものである。
[Detailed description of the invention] The present invention has excellent flat smoothness and small in-plane optical anisotropy, and at the same time, the in-plane anisotropy of the film due to dimensional changes due to severe thermal treatment is small. The present invention relates to a biaxially oriented polyester film suitable for magnetic sheet films such as small floppy disks and electrophotographic base films.

の  と  すべき ポリエステル二軸配向フィルムはその優れた性質から種
々の工業用途に供せられているが、特にフロッピーディ
スク及び電子写真用等磁気シートの基体フィルムとして
有用である。
Biaxially oriented polyester films are used in various industrial applications due to their excellent properties, and are particularly useful as base films for magnetic sheets for floppy disks and electrophotography.

磁気ディスク及び電子写真用途等磁気シートにおいては
平担易滑である事は第1条件であるが、高密度化の要請
により線膨張係数、湿度膨張係数、熱収縮率等の寸法変
化に関する性質が、フィルムの面内のいずれの方向につ
いても等方向である事が望まれている。これらの性質が
等方向でない場合、異なる環境のおかれた時トラックの
位置がヘッドの位置とずれてしまうため録画、再生が出
来なくなる。この為トラック密度があげられないという
問題が生ずる。
The first condition for magnetic sheets used in magnetic disks and electrophotography is to be flat and smooth, but due to the demand for higher densities, properties related to dimensional changes such as linear expansion coefficient, humidity expansion coefficient, and thermal contraction rate are changing. , it is desired that the film be oriented in the same direction in all directions within the plane of the film. If these properties are not in the same direction, the track position will deviate from the head position under different environments, making recording and playback impossible. Therefore, a problem arises in that the track density cannot be increased.

これらの性質を満たすフィルムとしてこれまで磁性層を
塗布する前の二軸延伸ポリエステルフィルムの面内の複
屈折率の異方性が小さくかつ過酷な湿熱処理後の非可逆
変化による面内の寸法変化の異方性が小さいフィルムを
供する事が提案されてきた(特開昭59−139131
号)。
Until now, films that meet these properties have been characterized by small in-plane birefringence anisotropy of biaxially stretched polyester films before coating with a magnetic layer, and in-plane dimensional changes due to irreversible changes after harsh moist heat treatment. It has been proposed to provide a film with small anisotropy (Japanese Patent Application Laid-Open No. 139131/1983).
issue).

上記に述べられたフィルムは磁気テープ化工程において
カレンダー処理工程のないものにおいては有効であった
が、カレンダー処理工程を伴うフロッピーディスク、電
子写真用途等の磁気シートにおいては、磁性層塗布前に
おいては確かに面内異方性が良好であるが、磁性層を塗
布し製品となった後では湿熱処理等の非再的過程を踏む
ため、それに伴う面内の寸法変化の異方性が極めて大き
くなってしまい高密度化には寄与しないものであった。
The above-mentioned film was effective in the magnetic tape production process without a calendering process, but in the case of magnetic sheets for floppy disks, electrophotography, etc. that require a calendering process, before the magnetic layer is coated, It is true that the in-plane anisotropy is good, but since non-recurrence processes such as moist heat treatment are performed after the magnetic layer is applied and the product is made, the anisotropy of the in-plane dimensional change that accompanies this process is extremely large. Therefore, it did not contribute to higher density.

ここで非可逆的な寸法変化とは、磁気ディスク、電子写
真用磁気シートの最も過酷な使用、保存及び輸送環境を
想定した、例えば53°C190%湿度、72時間なる
条件の湿熱処理を施した後のフィルムに見られる処のフ
ィルムの伸縮である。
Here, irreversible dimensional change is assumed to be the harshest use, storage and transportation environment for magnetic disks and magnetic sheets for electrophotography, such as when subjected to moist heat treatment at 53°C, 190% humidity, and 72 hours. This is the expansion and contraction of the film seen in later films.

ロ  を ゛するための手 本発明者はフィルムの平担易滑性に優れ、かっ磁気シー
ト化後の面内の配向の異方性及び非可逆変化での面内の
収縮率の異方性が小さなフィルムを得るべく鋭意検討の
結果、カレンダー処理前後でフィルムはその面内の屈折
率の異方性は変化しないのに対し、非可逆変化による寸
法変化の面内異方性はある特殊な変化を示す事の新しい
知見を得、その新知見に基づいて本発明に到達したもの
である。
The present inventor has discovered that the film has excellent smoothness when flattened, and the anisotropy of the in-plane orientation after forming into a magnetic sheet and the anisotropy of the in-plane shrinkage rate upon irreversible change. As a result of intensive studies to obtain a film with a small The present invention was achieved based on the new knowledge that shows changes.

すなわち本発明はポリエステルフィルムの偏光蛍光強度
より求まるR(45”)が0式を満たすフィルムにおい
て、53℃、90%湿度の条件下で72時間処理後のフ
ィルムにおける非可逆過程での長手方向の収縮率(払M
D)及び巾方向の収縮率(cATo)の差が0式を満た
す磁気シート用ポリエステルフィルム、 0.95≦R(45°)≦1.05・・・■払rD  
d’=MO≧15(P)・ ・ ・■及びその製造法に
関するものである。
In other words, the present invention is a film in which R(45''), which is determined from the polarized fluorescence intensity of a polyester film, satisfies the formula 0, and the longitudinal direction of the film after being treated for 72 hours at 53°C and 90% humidity in an irreversible process. Shrinkage rate (payment M
D) and a polyester film for magnetic sheets where the difference in shrinkage rate (cATo) in the width direction satisfies the formula 0, 0.95≦R (45°)≦1.05...■Payment rD
d'=MO≧15(P)・・・■ and its manufacturing method.

ここで、R(45°)はポリエステルフィルムの偏光蛍
光強度よりの値であり、”l−1c)及びぺ丁pはそれ
ぞれ53℃、90%湿度条件下で72時間処理後のフィ
ルムにおける非可逆過程での長手方向の収縮率及び巾方
向の収縮率である。
Here, R (45°) is the value from the polarized fluorescence intensity of the polyester film, and "l-1c)" and "P" are the irreversible values of the film after being processed for 72 hours at 53°C and 90% humidity. These are the shrinkage rate in the longitudinal direction and the shrinkage rate in the width direction during the process.

本発明にいうポリエステルとは、テレフタル酸、イソフ
タル酸、ナフタレン−2,6−ジカルボン酸のごとき芳
香族ジカルボン酸又はそのエステルと、エチレングリコ
ール、ジエチレングリコール、テトラメチレングリコー
ル、ネオペンチルグリコール等のジオールとを重縮合さ
せて得ることのできるポリマーである。
The polyester referred to in the present invention refers to aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalene-2,6-dicarboxylic acid or esters thereof, and diols such as ethylene glycol, diethylene glycol, tetramethylene glycol, and neopentyl glycol. It is a polymer that can be obtained by polycondensation.

該ポリエステルは芳香族ジカルボン酸とグリコールとを
直接重縮合させて得られる他、芳香族ジカルボン酸ジア
ルキルエステルとグリコールとをエステル交換反応させ
た後1重縮合せしめるか、あるいは芳香族ジカルボン酸
のジグリコールエステルを重縮合せしめる等の方法によ
っても得られる。
The polyester can be obtained by direct polycondensation of aromatic dicarboxylic acid and glycol, or can be obtained by single polycondensation after transesterification of aromatic dicarboxylic acid dialkyl ester and glycol, or by monopolycondensation of aromatic dicarboxylic acid dialkyl ester and glycol, or by polycondensation of aromatic dicarboxylic acid dialkyl ester and glycol. It can also be obtained by methods such as polycondensation of esters.

かかるポリマーの代表的なものとしては、ポリエチレン
テレフタレートやポリエチレン−2,6ナフタレンジカ
ルポキシレート等が挙げられる。
Typical examples of such polymers include polyethylene terephthalate and polyethylene-2,6 naphthalene dicarpoxylate.

このポリマーは共重合されないホモポリマーであっても
よく、又その特性を低下させない限りにおいてジカルボ
ン酸成分の15モル%以下が非芳香族ジカルボン酸成分
であり、及び/又はジオール成分の15モル%以下が脂
肪族グリコール以外のジオール成分であるような共重合
ポリエステルであってもよい。特に磁性層との接着性を
向上させるべ≦ジオール成分としてポリエチレングリコ
ール、ポリテトラメチレングリコール等ポリアルキレン
グリコールを共重合する事は好ましい。
The polymer may be a non-copolymerized homopolymer, and up to 15 mol% of the dicarboxylic acid component is a non-aromatic dicarboxylic acid component, and/or up to 15 mol% of the diol component, as long as its properties are not impaired. It may be a copolymerized polyester in which is a diol component other than aliphatic glycol. In particular, it is preferable to copolymerize a polyalkylene glycol such as polyethylene glycol or polytetramethylene glycol as a diol component that improves adhesiveness with the magnetic layer.

さらに前記ポリエステルと他の重合体とのポリマーブレ
ンドであってもよい、ブレンドできる重合体としてポリ
アミド、ポリオレフィン、他種ポリエステル(ポリカー
ボネートを含む)が例示される。
Furthermore, it may be a polymer blend of the polyester and another polymer, and examples of blendable polymers include polyamide, polyolefin, and other types of polyesters (including polycarbonate).

本発明のポリエステルフィルムは二軸延伸、熱固定後の
フィルムの偏光蛍光強度より求まるR(45°)の値が
95≦R(45°)≦1.05でなければならない。こ
のR(45°)の値は温湿度膨張係数と関係する指標で
あり、カレンダー処理前後において変化しないので、カ
レンダー処理前のフィルムにおいて満たしていればよい
(条件l) これに対し、非可逆変化による寸法変化の面内異方性は
カレンダー処理前後で極めて大きく変化を呈する。例え
ばカレンダー処理前のフィルムの非可逆変化による寸法
変化の面内異方性のないフィルムをカレンダー処理する
とカレンダー処理条件により変化量は異なるが大なり小
なり異方性が大きくなる。つまり長手方向の非可逆過程
での寸法が収縮を示すのに対し、巾方向の非可逆過程で
の寸法は膨張してしまい面内の異方性が極めて大きくな
ってしまうものである。この現出は明確ではないが、お
そらくカレンダー処理時にフィルムのTg近傍もしくは
それ以上の高温で長手方向にテンションがかかるため処
理後、長手方向に収縮してしまうものと思われる。
The polyester film of the present invention must have an R(45°) value of 95≦R(45°)≦1.05, which is determined from the polarized fluorescence intensity of the film after biaxial stretching and heat setting. The value of R (45°) is an index related to the temperature-humidity expansion coefficient and does not change before and after calendering, so it is sufficient that it is satisfied in the film before calendering (condition 1).On the other hand, irreversible change The in-plane anisotropy of the dimensional change due to the calendering process shows an extremely large change before and after the calendering process. For example, when a film without in-plane anisotropy in dimensional changes due to irreversible changes in the film before calendering is calendered, the anisotropy increases to a greater or lesser extent, although the amount of change varies depending on the calendering conditions. In other words, the dimensions in the irreversible process in the longitudinal direction show contraction, whereas the dimensions in the irreversible process in the width direction expand, resulting in extremely large in-plane anisotropy. Although the reason for this appearance is not clear, it is probably because tension is applied in the longitudinal direction at a high temperature close to or higher than the Tg of the film during calendering, causing the film to shrink in the longitudinal direction after processing.

ところで、カレンダー処理前のフィルムの非可逆過程の
寸法変化において、巾方向の寸法変化が収縮を示しかつ
巾方向の収縮が長手方向に比べて大きいフィルムを製造
することによりカレンダー処理後のフィルムの非可逆過
程の寸法変化の面内異方性を低く抑える事が出来る事が
わかった。このカレンダー処理前のフィルムの長手方向
と巾方向の収縮の程度については、カレンダー処理条件
により変化するものであって一概に決まるものではない
が、過酷な温熱処理による寸法変化のフィルム面内異方
性の小さいフィルムを得るためには、少くとも以下に定
義する非可逆過程での巾方向の収縮率(払TD)と長手
方向の収縮率(ぺ閂0)の差cl=丁〇−払PIDが1
5P以上である事が必要である(条件2)。
By the way, in the irreversible dimensional change of the film before calendering, the dimensional change in the width direction shows shrinkage, and by producing a film whose shrinkage in the width direction is larger than that in the longitudinal direction, the non-reversible process of the film after calendering can be improved. It was found that the in-plane anisotropy of the dimensional change during the reversible process can be suppressed to a low level. The degree of shrinkage in the longitudinal and width directions of the film before calendering varies depending on the calendering conditions and cannot be absolutely determined, but the in-plane anisotropy of the film due to dimensional changes due to severe thermal treatment is In order to obtain a film with low elasticity, at least the difference between the shrinkage rate in the width direction (tightness TD) and the shrinkage rate in the longitudinal direction (penetration 0) in the irreversible process defined below, cl = 0 - weighted PID. is 1
It is necessary to have 5P or more (condition 2).

本発明のフィルムは上記に述べた条件1、条件2を同時
に満足するフィルムである9条件1・、条件2をそれぞ
れ単独に満たすフィルムはこれまでにも知られているが
、同時に満たすフィルムは知られていない1例えば条件
1を満たすフィルムを得るためには縦横の延伸をバラン
スさせれば良いが、このようなフィルムでは条件2を満
たすフィルムは得られない事が多い。又、逆に条件2を
満たすべく例えば熱固定時巾出ししたり横延伸倍率を大
きくすると、面内の屈折率の異方性が大きくなってしま
い、条件1を満たさなくなってしまう訳である。
The film of the present invention is a film that simultaneously satisfies Conditions 1 and 2 described above.9 Films that satisfy Conditions 1 and 2 individually have been known, but no film that satisfies them at the same time has been known. For example, in order to obtain a film that satisfies condition 1, it is sufficient to balance the longitudinal and lateral stretching, but it is often not possible to obtain a film that satisfies condition 2 with such a film. On the other hand, if, for example, the width is increased during heat setting or the lateral stretching ratio is increased in order to satisfy condition 2, the anisotropy of the in-plane refractive index increases, and condition 1 is no longer satisfied.

以下、前記条件1、条件2を満たす本発明のフィルムの
製造方法について説明する。
Hereinafter, a method for producing a film of the present invention that satisfies Conditions 1 and 2 will be described.

粒子を含有したポリエステル原料を常法の手段で乾燥し
、押出機を通して溶融押出をし、回転冷却体ドラム上で
冷却固化して未延伸ポリエステルシートを成形する。こ
のようにして得た未延伸フィルムをまず縦方向に100
℃〜130℃の温度でΔnが0.015〜0.055と
なるように延伸し、更に縦方向に90℃〜150℃の温
度範囲で1.1〜2.0倍延伸し横延伸前縦延伸後の複
屈折率Δnを0.085以下、好ましくは0.060以
下としたのち1次いで横方向に3〜4.5倍延伸し、再
度縦方向に0.95≦R(45°)≦1.05となるよ
う120℃〜200℃で1.05〜1.5倍再縦延伸し
、必要に応じて熱固定を行なう。又、再縦延伸において
R(45°)〉1゜05となるよう延伸したのち更に横
方向に15.0℃〜210℃で0.95≦R(45°)
≦1.05となるよう1.05〜1.5倍再横延伸する
事も好ましい。
The polyester raw material containing the particles is dried by a conventional method, melt-extruded through an extruder, and cooled and solidified on a rotating cooling drum to form an unstretched polyester sheet. The unstretched film thus obtained was first
Stretched at a temperature of ℃ to 130℃ so that Δn becomes 0.015 to 0.055, and further stretched 1.1 to 2.0 times in the longitudinal direction at a temperature range of 90℃ to 150℃. The birefringence Δn after stretching is set to 0.085 or less, preferably 0.060 or less, and then stretched 3 to 4.5 times in the transverse direction, and again in the longitudinal direction 0.95≦R (45°)≦ The film is longitudinally stretched again by 1.05 to 1.5 times at 120° C. to 200° C. so that the film has a diameter of 1.05, and heat setting is performed as necessary. In addition, in the longitudinal stretching again, after stretching to R (45°)>1°05, further in the transverse direction at 15.0°C to 210°C, 0.95≦R(45°)
It is also preferable to re-transversely stretch the film by 1.05 to 1.5 times so that ≦1.05.

該延伸処方において第1段目の縦延伸温度がスーパード
ローもしくはその近傍以上の温度で延伸することが重要
である。このような延伸を行なう事により熱固定後の長
手方向の収縮率を低くすることが出来る。
In the stretching recipe, it is important that the first stage longitudinal stretching temperature be at or above super draw. By performing such stretching, the shrinkage rate in the longitudinal direction after heat setting can be lowered.

更に出来上がった磁気シートの平担易滑性を向上させる
ためには、突起と該突起を核とした長径が少くとも0.
5 Pmの窪みとからなる凹凸単位のフィルム表面積1
mm2当りの個数A(個/mm2)が 0≦A≦5000 を満足するフィルムであることが好ましい、5000個
以上では平担性に優れるが易滑性の点で劣るため好まし
くない。
Furthermore, in order to improve the smoothness of the finished magnetic sheet when it is flattened, the length of the protrusions and the major axis of the protrusions must be at least 0.
Film surface area of a concavo-convex unit consisting of a depression of 5 Pm 1
It is preferable that the film has a number A per mm2 (numbers/mm2) of 0≦A≦5000.If the number is 5000 or more, it is not preferable because it has excellent flatness but poor slipperiness.

このようなフィルムを得るためには(: a CO3+
A1203 g BaSO4(’)ような平均粒径0.
1〜10Pの添加粒子、あるいはエステル交換触媒残渣
による析出粒子が0.01〜1.5%含有されているポ
リエステルを上述の延伸条件で製膜することにより得ら
れ、Aは粒子量及び横延伸前縦延伸後の複屈折率Δnに
依存する。
In order to obtain such a film (: a CO3+
A1203 g BaSO4 (') average particle size 0.
It is obtained by forming a film of polyester containing 0.01 to 1.5% of added particles of 1 to 10P or particles precipitated by transesterification catalyst residue under the above-mentioned stretching conditions, where A is the particle amount and the transverse stretching. It depends on the birefringence Δn after the previous longitudinal stretching.

又、本発明のスーパードローもしくはその近傍以上の延
伸をするに当っては、粘度が高い程同−のΔnを得る際
の延伸倍率が高い事が分った。つまりフィルム粘度が高
い径縮方向の総合延伸倍率が向上するため、生産性が向
上しコストダウンを計り得る。それ故、本発明の延伸に
際してはフィルム粘度は高い程よく、0.60以上好ま
しくは0.63以上である。
Furthermore, it has been found that when drawing at or above the super draw of the present invention, the higher the viscosity, the higher the drawing ratio when obtaining the same Δn. In other words, since the overall stretching ratio in the radial contraction direction where the film viscosity is high is improved, productivity can be improved and costs can be reduced. Therefore, in the stretching of the present invention, the higher the film viscosity, the better, and it is 0.60 or more, preferably 0.63 or more.

A1じす1果 以上1本発明のフィルムはフロッピーディスク。A1 Jisu 1 fruit Above 1, the film of the present invention is a floppy disk.

電子写真等、カレンダー処理をする磁気シートの高密度
化を要するフィルムにおいて、面内異方性。
In-plane anisotropy occurs in films that require high density magnetic sheets for calendar processing, such as electrophotography.

非可逆過程の寸法変化の面内異方性、平担易滑性に優れ
たフィルムである。
This film has excellent in-plane anisotropy of dimensional changes during irreversible processes and smooth flatness.

大胤銖 以下に本発明を実施例で更に詳しく説明するが、本発明
がこれらの実施例に限定されるものでないことは言うま
でもない。
EXAMPLES The present invention will be explained in more detail with reference to Examples below, but it goes without saying that the present invention is not limited to these Examples.

フィルムの各物性の評価法を以下に示す。The evaluation method for each physical property of the film is shown below.

(1)複屈折率 カールツアイス社製偏光顕微鏡により、リターデーショ
ンを測定し、次式により複屈折率(Δn)を求めた。
(1) Birefringence Retardation was measured using a polarizing microscope manufactured by Carl Zeiss, and birefringence (Δn) was determined using the following formula.

Δn=R 但しR:リターデーション d:フィルム厚さ く2)摩擦係数(、”) 固定した硬質クロムメッキ金属ロール(直径6mm)に
フィルムを巻き付き角135°(θ)で接触させ、53
g(T2)の荷重を一端にかけて1m/minの速度で
これを走行させて他端の抵抗力(T+  (g))を測
定し、次式により走行中の摩擦係数を求めた。
Δn=R However, R: Retardation d: Film thickness 2) Coefficient of friction (,”) A film is brought into contact with a fixed hard chrome-plated metal roll (diameter 6 mm) at a winding angle of 135° (θ), 53
A load of g (T2) was applied to one end and the vehicle was run at a speed of 1 m/min, the resistance force (T+ (g)) at the other end was measured, and the coefficient of friction during running was determined using the following equation.

、、、=1/ρ l n (T+ /T2 )=0.4
24 in (T+ 153)(3)中心線平均表面粗
さくRa) 小板研究所社製表面粗さ測定器(SE−3FK)によっ
て次のように求めた。触針の先端半径は2Pm、荷重は
30mgである。フィルム断面曲線からその中心線の方
向に基準長さL (2,5mm)の部分を抜き取り、こ
の抜き取り部分の中心線をX軸、縦倍率の方向をY軸と
して、粗さ曲線y=f(x)f表わした時、次の式で与
えられた値を%mで表わす。但し、カットオフ値は80
 Pmである。Raは縦方向に5点、横方向に5点の計
10点の平均値を求めた。
,,,=1/ρ l n (T+ /T2)=0.4
24 in (T+ 153) (3) Center line average surface roughness Ra) It was determined as follows using a surface roughness meter (SE-3FK) manufactured by Koita Research Institute. The tip radius of the stylus was 2 Pm, and the load was 30 mg. A section of standard length L (2.5 mm) is extracted from the film cross-sectional curve in the direction of its center line, and the roughness curve y=f( x) When expressed as f, the value given by the following formula is expressed in %m. However, the cutoff value is 80
It is Pm. For Ra, the average value of a total of 10 points, 5 points in the vertical direction and 5 points in the horizontal direction, was determined.

(4)突起周辺に窪を有する凹凸単位(プロペラ)の個
数(A) カールツアイス社製微分干渉顕微鏡でアルミニウム蒸着
したフィルムの表面を750倍で写真撮影し1合計1m
m2のフィルム表面積当り突起を核とした長径が少なく
とも0.5.−mの窪からなる凹凸単位の数A(個/m
m2)を数えた。
(4) Number of uneven units (propellers) with depressions around the protrusions (A) The surface of the aluminum-deposited film was photographed at a magnification of 750 times using a Carl Zeiss differential interference microscope. 1 total 1 m
The major axis of the protrusion per m2 film surface area is at least 0.5. - Number A of uneven units consisting of m depressions (pieces/m
m2) was counted.

(5)R(45°) フィルムサンプルを蛍光剤を含む水浴中に浸漬、風乾し
、このサンプルを日本分光fJiF  M−1偏光蛍光
強度を求め下記0式の定義の従ってR(45°)を求め
る。
(5) R (45°) A film sample was immersed in a water bath containing a fluorescent agent, air-dried, and the JASCO fJiF M-1 polarized fluorescence intensity was determined using the sample. demand.

1  (0°):縦方向の偏光蛍光強度■ (90°)
:縦方向と直角方向の偏光蛍光強度I (45°):縦
方向と45°の方向の偏光蛍光強度 (6)フィルム粘度 試料200mgをフェノール/テトラクロルエタン=5
0150の混合溶液20m1に加え約llO℃1時間加
熱溶解後30℃で測定した。
1 (0°): Vertical polarized fluorescence intensity ■ (90°)
: Polarized fluorescence intensity I in the longitudinal direction and perpendicular direction (45°): Polarized fluorescence intensity in the longitudinal direction and the 45° direction (6) Film viscosity 200 mg of sample was mixed with phenol/tetrachloroethane = 5
The mixture was added to 20 ml of a mixed solution of 0150 and heated to dissolve at about 110° C. for 1 hour, and then measured at 30° C.

(7)温熱処理及び処理後の寸法変化測定法測定方向に
沿って10mm巾、50mm長(811定方向)のサン
プルを切り出し、これを長手方向に沿って半分に切断し
1片方を53℃、90部湿度に調整されたオーブンに自
由端で放置する。未処理サンプルと処理サンプルとを密
着させて並べ、両端部のずれを顕微鏡で読み取った。フ
ィルム面内で、180°にわたり10°毎に測定し、ず
れの最大値と最小値の差の絶対値を原長(50mm)に
対する%で表わし、フィルムの面内寸法変化率とした。
(7) Heat treatment and dimensional change measurement method after treatment Cut out a sample 10 mm wide and 50 mm long (811 direction) along the measurement direction, cut it in half along the longitudinal direction, and heat one half at 53°C. Place the free end in an oven adjusted to 90 parts humidity. The untreated sample and the treated sample were placed in close contact with each other, and the deviation at both ends was read using a microscope. Measurements were made every 10 degrees over 180 degrees within the film plane, and the absolute value of the difference between the maximum and minimum deviation values was expressed as a percentage of the original length (50 mm), and was taken as the in-plane dimensional change rate of the film.

なお、伸張をマイナス、収縮をプラスで表わした。本実
施例においては、寸法変化の最大値と最小値が得られる
方向は、いずれのサンプルについてもフィルムの縦方向
又は横方向に一致した。
In addition, extension was expressed as a minus sign, and contraction was expressed as a plus sign. In this example, the direction in which the maximum and minimum dimensional changes were obtained coincided with the longitudinal or lateral direction of the film for all samples.

(8)線膨張係数 日本自動制御社製定荷重伸び量測定装置(モデル/TL
2)を用いて、12.7mm巾、250mm長(測定方
向)のサンプルフィルムに27g/mm2の張力をかけ
、15℃/minで昇温した際の温度、伸び図より30
〜50℃の2点を直線で結び、その勾配を求めた。
(8) Linear expansion coefficient Constant load elongation measuring device manufactured by Japan Automatic Control Co., Ltd. (Model/TL
2), a tension of 27 g/mm2 was applied to a sample film with a width of 12.7 mm and a length of 250 mm (measurement direction), and the temperature was raised at a rate of 15°C/min.
Two points at ~50°C were connected with a straight line, and the slope was determined.

失差五土 (ポリエステルの製造法) ジメチルテレフタレート100部、エチレングリコール
70部、酢酸カルシウム−水塩0.10部及び酢酸リチ
ウム二水塩0.17部を反応器に仕込み、加熱昇温する
と共にメタノールを留出させてエステル交換反応を行な
い、反応開始後約4時間を要して230℃に達せしめ、
実質的にエステル交換反応を終了した。
Drift Goto (Production method of polyester) 100 parts of dimethyl terephthalate, 70 parts of ethylene glycol, 0.10 parts of calcium acetate hydrate, and 0.17 parts of lithium acetate dihydrate were charged into a reactor, and the temperature was raised while heating. Methanol was distilled off to perform a transesterification reaction, and it took about 4 hours after the start of the reaction to reach 230°C.
The transesterification reaction was substantially completed.

次にこの反応生成物にトリエチルホスフェート0.35
部を添加し、更に重縮合触媒として二酸化アンチモン0
.05部を添加した後、常法に従って重合し、ポリエス
テルを得た。該ポリエステル中には粒径およそ0.5〜
IP程度の均一で*aなカルシウム、リチウム及びリン
元素を含む析出粒子が多数認められた。該ポリエステル
Aは魁〕=0.65であった。
Next, add 0.35% of triethyl phosphate to this reaction product.
of antimony dioxide as a polycondensation catalyst.
.. After adding 05 parts, polymerization was carried out according to a conventional method to obtain a polyester. The polyester contains particles with a particle size of approximately 0.5 to
A large number of precipitated particles containing calcium, lithium, and phosphorus elements were observed to be as uniform as IP. The polyester A had a weight ratio of 0.65.

別途、このような内部析出粒子を殆んど含まないポリエ
ステルB ((yJ) =0.65)を製造し先のポリ
エステルとA/B=1/1  (重量比)の割合で混合
し、製膜用原料とした。
Separately, polyester B ((yJ) = 0.65) containing almost no such internal precipitated particles is produced and mixed with the previous polyester at a ratio of A/B = 1/1 (weight ratio). It was used as a raw material for membranes.

(製膜法) 上記原料を常法により乾燥し、285℃で押出機よりシ
ート状に押出して急冷し無定形シートとした。
(Film forming method) The above raw material was dried by a conventional method, extruded into a sheet form from an extruder at 285°C, and rapidly cooled to form an amorphous sheet.

該無定形シートを縦方向に110℃で3.6倍延伸しΔ
ntt0.040としたのち更に縦方向に90℃で1.
45倍延伸した。かくして得られたフィルムをテンター
で横方向に100℃、4.3倍延伸し207℃で熱固定
して15)−のフィルムを得た。フィルム粘度は0.6
3であった。該フィルムを常法にて磁性層を塗布し、1
10℃、300 K g / c mの線圧にて7段カ
レンダー処理を施し、磁気シートを形成した。磁性層塗
布前のフィルム及びカレンダー処理後の磁気シートの性
質を第1表に示す。
The amorphous sheet was stretched 3.6 times in the longitudinal direction at 110°C and Δ
After setting the ntt to 0.040, it was further heated at 90°C in the longitudinal direction for 1.
It was stretched 45 times. The thus obtained film was stretched in the transverse direction by a tenter at 100° C. by a factor of 4.3 and heat-set at 207° C. to obtain the film 15)-. Film viscosity is 0.6
It was 3. A magnetic layer was applied to the film in a conventional manner, and 1
Seven-stage calender treatment was performed at 10° C. and a linear pressure of 300 Kg/cm to form a magnetic sheet. Table 1 shows the properties of the film before applying the magnetic layer and the magnetic sheet after calendaring.

比較例1,2 実施例1において第2段目の縦延伸倍率を1゜3倍及び
1.55倍とした以外は実施例1と同様に製膜、評価し
た。
Comparative Examples 1 and 2 Films were formed and evaluated in the same manner as in Example 1, except that the longitudinal stretching ratio in the second stage was 1.3 times and 1.55 times.

比較例1のフィルムは縦方向の配向が横方向に比べて低
いため、R(45°)が0.95以下である。比較例2
のフィルムは縦方向の配向が横力向に比べて高いためR
(45°)が1.20と高く、かつ横方向と縦方向の収
縮率の差が小さいフィルムである。
Since the film of Comparative Example 1 has a lower orientation in the longitudinal direction than in the lateral direction, R (45°) is 0.95 or less. Comparative example 2
The film has a higher orientation in the longitudinal direction than in the lateral direction, so R
(45°) is as high as 1.20, and the difference in shrinkage rate in the horizontal and vertical directions is small.

比較例3 実施例1と同様の未延伸シートを用い85℃で3.75
倍縦延伸し、次いで横方向に100℃で3.8倍、4.
3倍延伸して207℃で熱固定して15)−のフィルム
を得、実施例1と同様の評価を行なった。
Comparative Example 3 3.75 at 85°C using the same unstretched sheet as in Example 1
Double longitudinal stretching, then 3.8x stretching in the transverse direction at 100°C, 4.
The film was stretched 3 times and heat-set at 207°C to obtain the film 15)-, and the same evaluation as in Example 1 was performed.

該フィルムは縦と横の配向がバランスしてR(45°)
は0.95と1.05の間にあるが、縦方向の収縮率が
高いため、横方向と縦方向の収縮率の差が小さいフィル
ムである。
The film is R (45°) with balanced vertical and horizontal orientation.
is between 0.95 and 1.05, but since the shrinkage rate in the longitudinal direction is high, the difference in shrinkage rates in the transverse direction and the longitudinal direction is small.

実施例2 実施例1と同等の無定形シートを用い、110℃で3.
0倍延伸しΔnを0.025としたのちioo℃で1.
23倍延伸しΔn=0.050とし、かくして得られた
縦延伸フィルムを次にステンターで140℃、4.2倍
横方向に延伸したのち140℃で熱処理し、150℃で
1.25倍再縦延伸を行ない、207℃で熱固定して1
5Pのフィルムを得た。該フィルムにおいて実施例1と
同様の評価を行なった。
Example 2 Using an amorphous sheet similar to Example 1, 3.
After stretching 0 times and setting Δn to 0.025, it was stretched to 1.0 times at ioo°C.
The longitudinally stretched film thus obtained was then stretched 4.2 times in the transverse direction at 140°C with a stenter, heat treated at 140°C, and stretched 1.25 times at 150°C. Stretch longitudinally and heat set at 207°C to obtain 1
A 5P film was obtained. The same evaluation as in Example 1 was performed on this film.

実施例3 実施例2において横延伸倍率を3.8倍とし熱固定終了
時巾方向に0.3%巾出しし又縦方向に0.2%縦弛緩
を行なって15戸のフィルムを得評価した。
Example 3 In Example 2, the transverse stretching ratio was set to 3.8 times, and at the end of heat setting, the film was expanded by 0.3% in the width direction and longitudinally relaxed by 0.2% in the machine direction, and 15 films were obtained and evaluated. did.

比較例4 実施例1と同様の未延伸フィルムをまず85℃で2.4
倍縦延伸し△nを0.040としたのち100℃で1.
25倍延伸し縦延伸後のΔnを0゜065とし次いで1
40℃、3.9倍横延伸し207℃で熱固定し15.I
−のフィルムを得て評価した。
Comparative Example 4 The same unstretched film as in Example 1 was first heated at 85°C for 2.4
After double longitudinal stretching and setting Δn to 0.040, 1.
After stretching 25 times and longitudinally stretching, Δn is set to 0°065, and then 1
Transversely stretched 3.9 times at 40°C and heat-set at 207°C 15. I
- films were obtained and evaluated.

該フィルムは縦方向の配向が低くR(45°)が0.9
5より小さいばかりか、縦の収縮率が高いため6エ1)
’Mpも小さいフィルムである。
The film has a low longitudinal orientation and an R (45°) of 0.9.
Not only is it smaller than 5, but the vertical shrinkage rate is high, so 6e1)
'Mp is also a small film.

比較例5 比較例4の横延伸後のフィルムを更に1.2倍再縦延伸
したのち207℃で熱固定し15.−のフィルムを得、
評価した。
Comparative Example 5 The transversely stretched film of Comparative Example 4 was further longitudinally stretched by 1.2 times and then heat-set at 207°C. 15. -obtain a film of
evaluated.

該フィルムは比較例4を再縦延伸しているためR(45
°)は0.95と1.05の間に入っているが、比較例
4に比べて縦方向の収縮率が高くなったため’n  ”
HOが更に小さくなってしまったものである。
Since the film was longitudinally stretched again from Comparative Example 4, it had an R(45
°) is between 0.95 and 1.05, but this is because the shrinkage rate in the vertical direction is higher than that of Comparative Example 4.
HO has become even smaller.

これらの結果を第1表に示す。These results are shown in Table 1.

第1表の結果よりR(45°)及びベア。、ベアか−へ
MCIが本発明の特許請求の範囲の規定を満たすフィル
ムのみ磁気シートの性質、面内寸法変化率、線膨張係数
の最大と最小値の差が極めて良好である事が分かる。
From the results in Table 1, R (45°) and Bear. It can be seen that only the films whose bare MCI satisfies the provisions of the claims of the present invention have extremely good magnetic sheet properties, in-plane dimensional change rate, and the difference between the maximum and minimum values of the coefficient of linear expansion.

Claims (1)

【特許請求の範囲】 (1)ポリエステルフィルムの偏光蛍光強度より求まる
R(45°)が[1]式を満たすフィルムにおいて、5
3℃、90%湿度の条件下で72時間処理後のフィルム
における非可逆過程での長手方向の収縮率(α_M_D
)及び巾方向の収縮率(α_T_D)の差が2式を満た
す磁気シート用ポリエステルフィルム。 0.95≦R(45°)≦1.05・・・[1]α_T
_D−α_M_D≧15(μ)・・・[2](2)突起
と該突起を核とした長径が少くともO、5Mmの窪みと
からなる凹凸単位のフィルム表面積1mm^2当りの個
数A(個/mm^2)が下記式3の範囲である平担易滑
性に優れた特許請求の範囲第1項記載の磁気シート用ポ
リエステルフィルム。 0≦A≦5000・・・[3] (3)ポリエステル未延伸フィルムを100℃以上13
0℃以下の温度で複屈折率Δnが0.015〜0.05
5となるよう縦方向に延伸し更に同一方向に90℃〜1
50℃の温度範囲で再度縦方向に1.1〜2.0倍延伸
し、横延伸前、縦延伸後の複屈折率を0.085以下と
し、次いで横方向に延伸し、必要に応じて更に縦方向に
再延伸し、次いで熱固定することを特徴とする、下記[
1]及び[2]式を満たす磁気シート用ポリエステルフ
ィルムの製造方法。 0.95≦R(45°)≦1.05・・・[1]α_T
_D−α_M_D≧15(μ)・・・[2](ただし、
R(45°)はポリエステルフィルムの偏光蛍光強度よ
りの値であり、α_M_D及びα_T_Dはそれぞれ5
3℃、90%湿度条件下で72時間処理後のフィルムに
おける非可逆過程での長手方向の収縮率及び巾方向の収
縮率である。)
[Claims] (1) In a film in which R (45°) determined from the polarized fluorescence intensity of the polyester film satisfies the formula [1], 5
The shrinkage rate in the longitudinal direction (α_M_D
) and shrinkage rate (α_T_D) in the width direction that satisfy two formulas. 0.95≦R(45°)≦1.05...[1]α_T
_D-α_M_D≧15(μ)... [2] (2) Number A of uneven units per 1 mm^2 film surface area consisting of a protrusion and a depression with a major axis of at least 0 and 5 mm centered on the protrusion The polyester film for a magnetic sheet according to claim 1, which has excellent flat lubricity and has a polyester film/mm^2) in the range of formula 3 below. 0≦A≦5000...[3] (3) Polyester unstretched film at 100°C or higher13
Birefringence Δn is 0.015 to 0.05 at a temperature below 0°C
Stretched in the longitudinal direction so that the
Stretched again in the longitudinal direction by 1.1 to 2.0 times in the temperature range of 50 ° C., the birefringence index before and after the longitudinal stretching is 0.085 or less, then stretched in the transverse direction, and as necessary. The following [[
1] and [2] A method for producing a polyester film for a magnetic sheet that satisfies formulas. 0.95≦R(45°)≦1.05...[1] α_T
_D−α_M_D≧15(μ)...[2] (However,
R (45°) is the value from the polarized fluorescence intensity of the polyester film, and α_M_D and α_T_D are each 5
These are the shrinkage percentage in the longitudinal direction and the shrinkage percentage in the width direction in the irreversible process of the film after processing for 72 hours at 3° C. and 90% humidity. )
JP741585A 1985-01-21 1985-01-21 Polyester film for magnetic sheet Granted JPS61167531A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP741585A JPS61167531A (en) 1985-01-21 1985-01-21 Polyester film for magnetic sheet

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP741585A JPS61167531A (en) 1985-01-21 1985-01-21 Polyester film for magnetic sheet

Publications (2)

Publication Number Publication Date
JPS61167531A true JPS61167531A (en) 1986-07-29
JPH0425855B2 JPH0425855B2 (en) 1992-05-01

Family

ID=11665230

Family Applications (1)

Application Number Title Priority Date Filing Date
JP741585A Granted JPS61167531A (en) 1985-01-21 1985-01-21 Polyester film for magnetic sheet

Country Status (1)

Country Link
JP (1) JPS61167531A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63288735A (en) * 1987-05-21 1988-11-25 Teijin Ltd Polyester film
US5366682A (en) * 1991-12-09 1994-11-22 Sumitomo Chemical Company, Limited Process for producing phase retarder
US5474731A (en) * 1993-04-12 1995-12-12 Sumitomo Chemical Company, Ltd. Process for producing phase retarder film

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63288735A (en) * 1987-05-21 1988-11-25 Teijin Ltd Polyester film
JPH0530375B2 (en) * 1987-05-21 1993-05-07 Teijin Ltd
US5366682A (en) * 1991-12-09 1994-11-22 Sumitomo Chemical Company, Limited Process for producing phase retarder
US5474731A (en) * 1993-04-12 1995-12-12 Sumitomo Chemical Company, Ltd. Process for producing phase retarder film

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