JPH02165413A - Polyester film for magnetic recording tape - Google Patents
Polyester film for magnetic recording tapeInfo
- Publication number
- JPH02165413A JPH02165413A JP32001388A JP32001388A JPH02165413A JP H02165413 A JPH02165413 A JP H02165413A JP 32001388 A JP32001388 A JP 32001388A JP 32001388 A JP32001388 A JP 32001388A JP H02165413 A JPH02165413 A JP H02165413A
- Authority
- JP
- Japan
- Prior art keywords
- film
- longitudinal direction
- polyester
- denotes
- refractive index
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229920006267 polyester film Polymers 0.000 title claims abstract description 17
- 239000000126 substance Substances 0.000 claims description 2
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 229920000728 polyester Polymers 0.000 description 12
- 238000001816 cooling Methods 0.000 description 6
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 5
- OFOBLEOULBTSOW-UHFFFAOYSA-N Malonic acid Chemical compound OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 5
- 239000002585 base Substances 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- 229920000642 polymer Polymers 0.000 description 5
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 4
- -1 aromatic dicarboxylic acids Chemical class 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 239000010419 fine particle Substances 0.000 description 4
- 150000002334 glycols Chemical class 0.000 description 4
- 238000006068 polycondensation reaction Methods 0.000 description 4
- 238000004804 winding Methods 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- 125000003118 aryl group Chemical group 0.000 description 3
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 3
- 150000002009 diols Chemical class 0.000 description 3
- 150000002148 esters Chemical class 0.000 description 3
- 230000009477 glass transition Effects 0.000 description 3
- 238000009998 heat setting Methods 0.000 description 3
- 239000003973 paint Substances 0.000 description 3
- 230000003746 surface roughness Effects 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 239000002518 antifoaming agent Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- WERYXYBDKMZEQL-UHFFFAOYSA-N butane-1,4-diol Chemical compound OCCCCO WERYXYBDKMZEQL-UHFFFAOYSA-N 0.000 description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 239000003086 colorant Substances 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- QQVIHTHCMHWDBS-UHFFFAOYSA-N isophthalic acid Chemical compound OC(=O)C1=CC=CC(C(O)=O)=C1 QQVIHTHCMHWDBS-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 239000003381 stabilizer Substances 0.000 description 2
- IIZPXYDJLKNOIY-JXPKJXOSSA-N 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine Chemical compound CCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCC[N+](C)(C)C)OC(=O)CCC\C=C/C\C=C/C\C=C/C\C=C/CCCCC IIZPXYDJLKNOIY-JXPKJXOSSA-N 0.000 description 1
- 239000005995 Aluminium silicate Substances 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 239000000020 Nitrocellulose Substances 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 241001422033 Thestylus Species 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 150000001339 alkali metal compounds Chemical class 0.000 description 1
- 150000001341 alkaline earth metal compounds Chemical class 0.000 description 1
- 235000012211 aluminium silicate Nutrition 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- AAEHPKIXIIACPQ-UHFFFAOYSA-L calcium;terephthalate Chemical compound [Ca+2].[O-]C(=O)C1=CC=C(C([O-])=O)C=C1 AAEHPKIXIIACPQ-UHFFFAOYSA-L 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 229910052570 clay Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 229920006037 cross link polymer Polymers 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 1
- 239000000787 lecithin Substances 0.000 description 1
- 229940067606 lecithin Drugs 0.000 description 1
- 235000010445 lecithin Nutrition 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- RXOHFPCZGPKIRD-UHFFFAOYSA-N naphthalene-2,6-dicarboxylic acid Chemical compound C1=C(C(O)=O)C=CC2=CC(C(=O)O)=CC=C21 RXOHFPCZGPKIRD-UHFFFAOYSA-N 0.000 description 1
- SLCVBVWXLSEKPL-UHFFFAOYSA-N neopentyl glycol Chemical compound OCC(C)(C)CO SLCVBVWXLSEKPL-UHFFFAOYSA-N 0.000 description 1
- 229920001220 nitrocellulos Polymers 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920001515 polyalkylene glycol Polymers 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 229920001228 polyisocyanate Polymers 0.000 description 1
- 239000005056 polyisocyanate Substances 0.000 description 1
- 229920002959 polymer blend Polymers 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 238000005809 transesterification reaction Methods 0.000 description 1
Landscapes
- Manufacture Of Macromolecular Shaped Articles (AREA)
- Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、オーディオあるいはビデオ用等の磁気記録テ
ープの基材として好適なポリエステルフィルムに関する
。更に詳しくは、機械的性質、熱的特性、厚さ斑に優れ
た磁気記録テープ用ポリエステルフィルムに関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polyester film suitable as a base material for magnetic recording tape for audio or video use. More specifically, the present invention relates to a polyester film for magnetic recording tape that has excellent mechanical properties, thermal properties, and thickness unevenness.
〔従来の技術および発明が解決しようとする課題〕ポリ
エステルニ軸配向フィルムは、優れた機械的性質、熱的
性質、電気的性質、耐薬品性等を有するための各種用途
に適用されており、特に磁気テープ用ベースフィルムと
して有用である。[Prior Art and Problems to be Solved by the Invention] Biaxially oriented polyester films are used in various applications due to their excellent mechanical properties, thermal properties, electrical properties, chemical resistance, etc. It is particularly useful as a base film for magnetic tapes.
ポリエステルフィルムを磁気テープ用ベースフィルムと
して用いた場合、用いるベースフィルムの特性が、磁気
テープとしての品質に強く影響を与えるため、磁気テー
プの技術進歩に伴ってベースフィルムに対する高品質化
の要求も近年ますます増大している。具体的には、ビデ
オ用磁気テープに対する長時間化、電磁変換特性の向上
環の要求がある。When polyester film is used as a base film for magnetic tape, the characteristics of the base film used have a strong influence on the quality of the magnetic tape, so in recent years there has been a demand for higher quality base films as magnetic tape technology advances. It is increasing. Specifically, there are demands for video magnetic tapes to have longer recording times and improved electromagnetic conversion characteristics.
しかしながらテープの長時間化のためにフィルムの縦強
度を高くして薄膜化すると、それに伴い、スキューが大
きくなる。また走行性を与えようとすると電磁変換特性
も悪化し、磁気テープ用ポリエステルフィルムとして好
適なものは得られていなかった。However, if the longitudinal strength of the film is increased to make the film thinner in order to extend the tape's length, the skew increases accordingly. Furthermore, when trying to impart runnability, the electromagnetic conversion properties also deteriorated, and a polyester film suitable for use in magnetic tapes could not be obtained.
本発明者らは、上記課題を解決すべく、鋭意検討した結
果、ポリエステルフィルムの物性がある特定の関係を満
たすものが磁気テープ用フィルムとして好適であること
を見い出し、本発明を完成するに至った。In order to solve the above problems, the present inventors have made extensive studies and have discovered that a polyester film that satisfies a certain physical property relationship is suitable as a film for magnetic tape, and has completed the present invention. Ta.
すなわち本発明め要旨は、下記式[1]〜[3]を同時
に満足することを特徴とする磁気記録テープ用ポリエス
テルフィルムに存する。That is, the gist of the present invention resides in a polyester film for magnetic recording tape, characterized in that it satisfies the following formulas [1] to [3] at the same time.
R5く 5 ・・・・・・・・・ ■S3゜
≦0.06 Fs −0,4・・・・・・・・・ 0
30分間処理後のフィルムの熱収縮率(%)を示し、F
Sはフィルムの縦方向の5%伸張時強度(kg/mm”
)を示し、nullはフィルム縦方向の屈折率を示し
1.nはフィルムの平均屈折率を示す。)以下、本発明
の詳細な説明する。R5ku 5 ・・・・・・・・・ ■S3゜ ≦0.06 Fs -0,4・・・・・・・・・ 0
The heat shrinkage rate (%) of the film after treatment for 30 minutes is shown, and F
S is the strength at 5% elongation in the longitudinal direction of the film (kg/mm”
), and null indicates the refractive index in the longitudinal direction of the film.1. n indicates the average refractive index of the film. ) Hereinafter, the present invention will be explained in detail.
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−ジカルボン酸のような芳
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ようなグリコールとを
重縮合させて得ることのできるポリマーである。かかる
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、重縮合させる方法、また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させる方法によって得る
ことができる。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 their esters, and ethylene glycol, diethylene glycol, tetramethylene glycol, neopentyl glycol, etc. It is a polymer that can be obtained by polycondensation with glycol. Such polyesters can be obtained by direct polycondensation of aromatic dicarboxylic acids and glycols, or by polycondensation after transesterification of aromatic dicarboxylic acid dialkyl esters and glycols, or by polycondensation of aromatic dicarboxylic acid dialkyl esters and glycols. It can be obtained by a method of polycondensing glycol esters.
かかるポリマーの代表的なものとして、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
ルボキシレート等が例示される。Typical examples of such polymers include polyethylene terephthalate and polyethylene-2,6-naphthalene dicarboxylate.
本発明のポリエステルはホモポリマーであってもよく、
またその特性を低下させない範囲、例えばジカルボン酸
成分の15モル%以下が主成分の芳香族ジカルボン酸以
外のジカルボン酸成分またはジオール成分の15モル%
以下が主成分ジオ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。The polyester of the present invention may be a homopolymer,
In addition, within a range that does not deteriorate its properties, for example, 15 mol% or less of the dicarboxylic acid component is 15 mol% of the dicarboxylic acid component other than the aromatic dicarboxylic acid as the main component or the diol component.
A copolymerized polyester having the following diol components other than the main component diol may be used.
更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。ブレンド出来る他の重合体として
は、ポリアミド、ポリオレフィン、ポリカーボネート、
他種ポリエステル等が挙げられる。また、ポリエステル
フィルムに易滑性を付与するために、微粒子を添加して
もよい、かかる微粒子としては、カリオン、クレー、炭
酸カルシウム、酸化ケイ素、テレフタル酸カルシウム、
酸化アルミニウム、球状シリカ、酸化チタン等の不活性
外部粒子、ポリエステル樹脂の溶融製膜に際して不溶な
高融点有機化合物、架橋ポリマー及びポリエステル合成
時に使用するアルカリ金属化合物、アルカリ土類金属化
合物等の金属化合物触媒によってポリエステル製造時に
ポリマー内部に形成される内部粒子の中から適宜選択さ
れる。当然各校子を単独で用いてもよいし、併用しても
よい。Furthermore, it may be a polymer blend of the polyester and another polymer. Other polymers that can be blended include polyamides, polyolefins, polycarbonates,
Examples include other types of polyester. Further, fine particles may be added to impart slipperiness to the polyester film. Examples of such fine particles include carrion, clay, calcium carbonate, silicon oxide, calcium terephthalate,
Inert external particles such as aluminum oxide, spherical silica, titanium oxide, etc., high melting point organic compounds that are insoluble during melt film formation of polyester resin, metal compounds such as alkali metal compounds and alkaline earth metal compounds used during crosslinked polymer and polyester synthesis. The catalyst is appropriately selected from internal particles formed inside the polymer during polyester production by the catalyst. Of course, each student may be used alone or in combination.
フィルム中に含まれる微粒子量は、通常0.005〜1
.5重量%の範囲であり、粒子の平均粒径は通常、0.
01〜5μmの範囲である。The amount of fine particles contained in the film is usually 0.005 to 1
.. 5% by weight, and the average particle size of the particles is typically 0.5% by weight.
The range is 0.01 to 5 μm.
また、本発明におけるポリエステルは、必要に応じて、
安定剤、着色剤、酸化防止剤、消泡剤等の添加剤を含有
するものであってもよい。In addition, the polyester in the present invention may include, if necessary,
It may contain additives such as stabilizers, colorants, antioxidants, and antifoaming agents.
以上詳述したポリエステルを用いて本発明のフィルムを
得ることができるが、得られたフィルムの縦方向5mに
おける厚さ斑R5は5%未満でなければならない。フィ
ルムの厚さ斑が5%以上ではテープ走行時の蛇行、巻き
乱れの他、電磁変換特性にも悪影響を与える。かかる厚
さ斑は3%以下が好ましい。The film of the present invention can be obtained using the polyester detailed above, but the thickness unevenness R5 of the obtained film in the longitudinal direction of 5 m must be less than 5%. If the thickness unevenness of the film is 5% or more, it causes meandering and irregular winding during tape running, and also adversely affects electromagnetic conversion characteristics. Such thickness unevenness is preferably 3% or less.
また本発明のフィルムの縦方向の5%伸張時強[F、値
と100℃、30分間処理後の熱収縮率S、。 ≦ 0
.06 FS −0,4・・・・・・・・・ ■こ
の0式を満足しないフィルムはスキュー特性、スリット
性、巻き特性(巻きズレ)、及びテープダメージ等で劣
り磁気テープ用として不適当である。Further, the strength [F, value] of the film of the present invention at 5% elongation in the longitudinal direction and the heat shrinkage rate S, after treatment at 100° C. for 30 minutes. ≦ 0
.. 06 FS -0,4・・・・・・・・・ ■Films that do not satisfy this formula 0 have poor skew characteristics, slitting characteristics, winding characteristics (wrapping misalignment), tape damage, etc., and are unsuitable for use in magnetic tapes. be.
なお、通常、磁気テープ用として用いられるフィルムの
Fs(aは12 kg/mm2以上であり、好ましくは
13 kg/mm”以上、長時間記録用では15kg/
mm”以上であり、好ましくは19 kg/no++2
以未満であり、好ましくは0.8%以下、更に好ましく
は0.6%以下である。フィルムの熱収縮率は小さい程
、スキュー改良効果が優れ、磁気テープ用として有用で
ある。Note that the Fs (a) of films used for magnetic tapes is usually 12 kg/mm2 or more, preferably 13 kg/mm or more, and 15 kg/mm for long-term recording.
mm” or more, preferably 19 kg/no++2
It is preferably 0.8% or less, more preferably 0.6% or less. The smaller the heat shrinkage rate of the film, the better the skew improvement effect, and the more useful it is for magnetic tapes.
更に本発明のフィルムの縦方向の5%伸張時強度F5、
縦方向の屈折率nHDおよび平均屈折率Tが下記0式を
満足することが必要である。Furthermore, the strength F5 at 5% elongation in the longitudinal direction of the film of the present invention,
It is necessary that the longitudinal refractive index nHD and the average refractive index T satisfy the following formula 0.
・・・轡
この■式を満足しないフィルムは生産性が劣り、コスト
アップとなるため好ましくない。...Films that do not satisfy the formula (2) are undesirable because they have poor productivity and increase costs.
以上の要件を同時に満足するフィルムが磁気テープ用と
して有用であるが、更に下記0〜0式を満足するフィル
ムが磁気テープ用フィルムとして特に優れた特性を有す
る。A film that satisfies the above requirements at the same time is useful as a magnetic tape, but a film that also satisfies the following formulas 0 to 0 has particularly excellent properties as a magnetic tape film.
0.002 ・Fs+1.43 ・n 2.17≦Δ
P≦0.002 ・Ps+ 1.43 ・n 2−1
5 ・・・・・” ■n≧0.0005・Fs+1
.5940 ・・・・・・−・−00式を満足し
ないフィルム、例えば面配向度ΔPが0.002・FS
+1.43・n−2,17未満となるフィルムはスリ
ット性に劣り、ΔPが0.002・Fs +1.43n
2.15を超えるフィルムでは電気特性、走行性お
よび生産性について劣ったものとなる。また0式を満足
しないフィルム、すなわち平均屈折率nが0.0005
・F−s+1.5940未満のフィルムはスキュー特
性が劣る。nが0.0006・F、+1.5928以上
であるフィルムが更にスキュー特性の点で優れる。0.002 ・Fs+1.43 ・n 2.17≦Δ
P≦0.002 ・Ps+ 1.43 ・n 2-1
5 ・・・・・・” ■n≧0.0005・Fs+1
.. 5940 ......--A film that does not satisfy the -00 formula, for example, a plane orientation degree ΔP of 0.002・FS
A film with a value less than +1.43・n−2,17 has poor slitting properties, and ΔP is 0.002・Fs +1.43n
Films with a molecular weight exceeding 2.15 have poor electrical properties, runnability, and productivity. Also, films that do not satisfy formula 0, that is, the average refractive index n is 0.0005.
-Films with less than F-s+1.5940 have poor skew characteristics. A film in which n is 0.0006·F, +1.5928 or more is even better in terms of skew characteristics.
また、フィルム表面の粗度(Ra )は通常06005
〜0.05μmの範囲であることが望ましい。In addition, the roughness (Ra) of the film surface is usually 06005
A range of 0.05 μm is desirable.
RaがO,OO5μm未満では巻き特性の点で劣り、0
.005μmを超えると磁気記録性が極めて悪化し好ま
しくない。If Ra is less than O,OO5μm, the winding characteristics will be poor, and 0
.. If it exceeds 0.005 μm, magnetic recording properties will deteriorate significantly, which is not preferable.
以上述べたように弐[1]〜[3]を同時に満足するフ
ィルム、好ましくは式■〜■を同時に満足するフィルム
が磁気テープ用途における高品質化、薄膜化、高画質化
に適応できるフィルムである。As mentioned above, a film that satisfies 2 [1] to [3] at the same time, preferably a film that satisfies formulas 2 to 3 at the same time, is a film that can be adapted to higher quality, thinner film, and higher image quality in magnetic tape applications. be.
次に本発明のポリエステルフィルムの製膜方法を更に詳
細に説明する。Next, the method for forming a polyester film of the present invention will be explained in more detail.
カオリン、シリカ、炭酸カルシウム、酸化アルミニウム
等の微細粒子及び安定剤、着色剤、消泡剤、有機滑剤、
ポリアルキレングリコール等の添加剤を必要に応じ含有
するポリエステルチップを常法の手段で乾燥し、押出機
を通して押出し、回転冷却ドラム上で冷却固化して未延
伸ポリエステルシートを形成する。この際、常法の静電
印加冷却法を用いるのが好適である。このようにして得
た実質的に非晶状態のフィルムを延伸倍率(λt)4.
0〜9.0の範囲内で縦方向に延伸し次いで横力向に延
伸倍率3.2倍以上で延伸し二軸配向フィルムを形成す
る。Fine particles such as kaolin, silica, calcium carbonate, aluminum oxide, stabilizers, colorants, antifoaming agents, organic lubricants,
The polyester chips, optionally containing additives such as polyalkylene glycol, are dried by conventional means, extruded through an extruder, and solidified by cooling on a rotating cooling drum to form an unstretched polyester sheet. At this time, it is preferable to use a conventional electrostatic application cooling method. The substantially amorphous film thus obtained was stretched at a stretching ratio (λt) of 4.
The film is stretched in the machine direction within a range of 0 to 9.0, and then stretched in the transverse direction at a stretching ratio of 3.2 times or more to form a biaxially oriented film.
本発明のフィルムを製造するに際し7ては、前記縦方向
の延伸が、
(A)非晶状態のフィルムを延伸倍率1.2〜4.0倍
で複屈折率がlXl0−’〜2.5X10−”となるよ
うに1段または多段で縦延伸し、
(B)フィルム温度をガラス転移点以下に冷却すること
なく、延伸倍率1.1〜3.5倍で複屈折率が3.0X
10−”〜8.0xlO−2となるように1段または多
段で縦延伸し、
(C)フィルム温度をガラス転移点以下に冷却した後、
(D)フィルムをガラス転移点以上に加熱して1段また
は多段で縦延伸する工程からなることが好ましい。In manufacturing the film of the present invention, in step 7, the stretching in the longitudinal direction is performed so that (A) the film in an amorphous state has a birefringence of 1X10-' to 2.5X10 at a stretching magnification of 1.2 to 4.0 times. (B) Without cooling the film temperature below the glass transition point, the birefringence is 3.0X at a stretching ratio of 1.1 to 3.5 times.
(C) After cooling the film temperature to below the glass transition point, (D) After heating the film to above the glass transition point, It is preferable to include a step of longitudinal stretching in one stage or in multiple stages.
また、横延伸後の二軸配向フィルムに必要に応じて再度
線及び/又は横延伸を行なってもよいが、横延伸後、直
ちに熱固定することが好ましい。その際の熱固定温度は
少なくとも200℃以上であリ、好ましくは210°C
以上である。Further, the biaxially oriented film after the transverse stretching may be subjected to line and/or transverse stretching again if necessary, but it is preferable to heat set immediately after the transverse stretching. The heat setting temperature at that time is at least 200°C or higher, preferably 210°C.
That's all.
以上述べたように本発明のフィルムは、磁気テープ用フ
ィルムとして極めて優れたものであり、通常、その厚み
は3〜15μmの範囲である。As described above, the film of the present invention is extremely excellent as a film for magnetic tape, and its thickness is usually in the range of 3 to 15 μm.
以下、実施例にて、本発明を更に具体的に説明するが、
本発明は、その要旨を超えない限り以下の実施例に限定
されるものでない。Hereinafter, the present invention will be explained in more detail with reference to Examples.
The present invention is not limited to the following examples unless it exceeds the gist thereof.
なお、フィルム及びテープの特性評価方法は次の通りで
ある。The characteristics of the film and tape were evaluated as follows.
(1) Fs値
■インテスコ製、引張試験機インナスコモデル2001
型を用いて、温度23℃、湿度50%RHに調節された
室内においてフィルムの縦方向に切り出した長さ50鰭
、幅151璽の試料フィルムを長手方向に50 u+/
minの速度で引張り、5%伸張時の強度をF、値とし
た。(1) Fs value ■ Tensile tester Innasco Model 2001 manufactured by Intesco
A sample film with a length of 50 fins and a width of 151 fins was cut out in the longitudinal direction using a mold in a room controlled at a temperature of 23°C and a humidity of 50% RH.
It was pulled at a speed of min, and the strength at 5% elongation was taken as the value F.
無張力状態で100℃雰囲気中30分間、熱処理しその
前後のサンプルの長さを測定することにより次式にて計
算した。The length of the sample was calculated by the following formula by heat-treating it in a 100°C atmosphere for 30 minutes in a tension-free state and measuring the length of the sample before and after the heat treatment.
熱収縮率(%)−
(3)厚さ斑R’ (%)
安置電気社製連続フィルム厚さ測定器(電子マイクロメ
ーター使用)により、二輪延伸フィルムの縦方向に沿っ
て測定し、(5m長さについて)次式より算出した。Thermal shrinkage rate (%) - (3) Thickness unevenness R' (%) Measured along the longitudinal direction of the two-wheel stretched film using a continuous film thickness measuring device manufactured by Anki Electric Co., Ltd. (using an electronic micrometer). Regarding length) Calculated from the following formula.
(4) nsm
アタゴ光学社製 アツベ式屈折計を用いて、23℃にて
ナトリウムD線に対するフィルム縦方向の屈折率を測定
した。(4) nsm The refractive index of the film in the longitudinal direction with respect to the sodium D line was measured at 23° C. using an Atsube refractometer manufactured by Atago Optical Co., Ltd.
(5) 平均屈折率T、面配向度ΔPアタゴ光学社製
アフベ式屈折計を用い、フィルム面内の屈折率の最大値
n r sそれに直角の方向の屈折率nβ、及びフィル
ムの厚さ方向の屈折率nαを測定し、次式より平均屈折
率及び面配向度を算出した。尚、屈折率の測定は、ナト
リウムD線を用い、23度で行なった。(5) Average refractive index T, degree of plane orientation ΔP Using an Afbe refractometer manufactured by Atago Optical Co., Ltd., the maximum value of the refractive index in the film plane n r s, the refractive index nβ in the direction perpendicular to it, and the thickness direction of the film The refractive index nα was measured, and the average refractive index and degree of plane orientation were calculated from the following formula. Note that the refractive index was measured using sodium D line at 23 degrees.
n =I八 (nα+nβ+nγ)
(6)摩擦係数(μd)
固定した硬質クロムメツキ金属ロール(直径6龍)にフ
ィルムを巻きつけ角135°(θ)で接触させ、53
g (Tz)の荷重を一端にかけて、1m/minの速
度でこれを走行させ他端の抵抗力(T +(g))を測
定し、次式により走行中の摩擦係数(μd)を求めた。n = I8 (nα + nβ + nγ) (6) Coefficient of friction (μd) A film was wound around a fixed hard chrome plated metal roll (diameter 6 mm) and brought into contact at an angle of 135° (θ), 53
A load of g (Tz) was applied to one end, and it was run at a speed of 1 m/min to measure the resistance force (T + (g)) at the other end, and the coefficient of friction (μd) during running was determined using the following formula. .
(7)表面粗度(Ra) 中心線平均粗さRa(μm)をもって表面粗さとした。(7) Surface roughness (Ra) The center line average roughness Ra (μm) was defined as the surface roughness.
■小板研究所社製表面粗さ測定機(SE−3F)を用い
て次のようにして求めた。すなわち、フィルム断面曲線
からその中心線の方向に基準長さL(2,5fl)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−r (x)で表わ
したとき、次の式で与えられた値を〔μm〕で表わす、
中心線平均粗さは、試料フィルム表面から10本の断面
曲線を求め、これらの断面曲線から求めた抜き取り部分
の中心線平均粗さの平均値で表わした。尚、触針の先端
半径は2μm、荷重は30■とし、カットオフは0.0
8鶴とした。■It was determined as follows using a surface roughness measuring machine (SE-3F) manufactured by Koita Research Institute. That is, a part with a reference length L (2,5 fl) is extracted from the film cross-sectional curve in the direction of its center line, and the roughness curve yr is set with the center line of this extracted part as the X axis and the vertical magnification direction as the y axis. When expressed as (x), the value given by the following formula is expressed in [μm],
The centerline average roughness was determined by determining 10 cross-sectional curves from the surface of the sample film, and was expressed as the average value of the centerline average roughness of the sampled portions determined from these cross-sectional curves. The tip radius of the stylus is 2 μm, the load is 30μ, and the cutoff is 0.0.
8 cranes.
(8)磁気テープ特性(磁気記録用媒体の特性)まず、
次に示す磁性塗料をポリエステルフィルムに塗布し、乾
燥後の膜厚を5μmとなるよう磁性層を形成した。すな
わち、磁性微粉末200部、ポリウレタン樹脂30部、
ニトロセルロース10部、塩酢ビ共重合体10部、レシ
チン5部、シクロへキサノン100部およびメチルエチ
ルケトン300部をボールミルにて48時間混合分散後
ポリイソシアネート化合物5部を加えて磁性塗料とし、
これをポリエステルフィルムに塗布した後、塗料が充分
乾燥固化する前に磁気配向させ、その後乾燥した。更に
、この塗布フィルムをスーパーカレンダーにて表面処理
を施し、2インチ幅にスリットしてビデオテープとした
。このビデオテープを松下電気側製NV−3700型ビ
デオデツキにより常連にて下記の磁気テープ特性を評価
した。VTRヘッド出力はシンクロスコープにより測定
周波数4メガヘルツにおけるVTRヘッド出力を測定し
、基準テープを0.0デシベル(d B)とし、その相
対値を(d B)表示した。(8) Magnetic tape characteristics (characteristics of magnetic recording media) First,
The following magnetic paint was applied to a polyester film to form a magnetic layer so that the film thickness after drying was 5 μm. That is, 200 parts of magnetic fine powder, 30 parts of polyurethane resin,
After mixing and dispersing 10 parts of nitrocellulose, 10 parts of salt-vinyl acetate copolymer, 5 parts of lecithin, 100 parts of cyclohexanone and 300 parts of methyl ethyl ketone in a ball mill for 48 hours, 5 parts of a polyisocyanate compound was added to prepare a magnetic paint.
After applying this to a polyester film, it was magnetically oriented before the paint was sufficiently dried and solidified, and then dried. Furthermore, this coated film was subjected to surface treatment using a supercalender, and was slit into 2-inch widths to make a videotape. The following magnetic tape characteristics of this videotape were evaluated using an NV-3700 video deck manufactured by Matsushita Electric. The VTR head output was measured using a synchroscope at a measurement frequency of 4 MHz, and the reference tape was set to 0.0 decibel (dB), and its relative value was expressed as (dB).
(i) スキュー量
クロマのビデオ信号を記録したビデオテープを再生し、
シバツク社製カラーモニター〇MM20−11にて遅延
掃引操作を行ない、画面上の歪み量をメジャーで読み取
り、モニター画面全幅の比をもって1水平走査時間に換
算し測定した結果、良好なものをO2全く不良のものを
×、その中間のものを△とした。(i) Play back a videotape on which a video signal with a skew amount chroma is recorded,
Performing a delayed sweep operation on a Shibatsu color monitor MM20-11, reading the amount of distortion on the screen with a tape measure, and converting it into one horizontal scanning time using the ratio of the full width of the monitor screen. Bad ones were rated as ×, and those in the middle were rated as △.
(ii) 耐エツジダメージ性
市販の家庭用VTRを用いて200回走行後、テープ端
部のひだ状の伸びを目視で評価した。(ii) Edge damage resistance After running the tape 200 times using a commercially available home VTR, the elongation of the folds at the ends of the tape was visually evaluated.
ランクA 全く伸びが認められない ランクB わずかではあるが伸びが認められる。Rank A: No growth observed at all Rank B: Although slight, growth is recognized.
ランクCはっきりひだ状の伸びが認められ、実用上使用
し難い。Rank C: Clear pleat-like elongation is observed, making it difficult to use practically.
(iii ) スリット性
磁気テープをスリットしたときのスリット部分の断面を
電子顕微鏡で観察し、断面に切り粉が残り磁性面が盛り
上がっているものは×、全く良好なものは○、中間のも
のを△とした。(iii) Observe the cross section of the slit part when slitting the slit magnetic tape with an electron microscope. If the cross section has chips remaining on the cross section and the magnetic surface is raised, it is ×, if it is completely good, it is ○, if it is in the middle, it is It was marked △.
(iv) 磁気テープの巻き特性
磁気テープを早送りで巻いたとき、テープの端面が不ぞ
ろいのものを×、全く良好なものをOlその中間を△と
した。(iv) Winding Characteristics of Magnetic Tape When a magnetic tape was wound in fast forward motion, a case where the end surface of the tape was uneven was marked as "x", a case where it was perfectly good was marked as "O", and a mark in between was marked as "fair".
実施例1
ポリエチレンテレフタレートチップ(固有粘度0.60
、平均粒径0.02μmのAj!zOs0.3重量%と
平均粒径0.7μmの炭酸カルシウム0.3重量%とを
重合時添加したもの)を180℃で5時間乾燥後、28
5℃でTダイからシート状にて押出し、45℃に保たれ
た回転ドラム上で冷却固化して幅350Dの未延伸非晶
質フィルムを得た。その際、公知の静電密着法を用いた
。得られた非晶質フィルムを多段のニップロールの周速
差を利用して、まず縦方向に第1段目としてフィルム温
度112°Cで1.6倍延伸後、連続して縦方向に第2
段目としてフィルム温度143℃で2.8倍延伸した。Example 1 Polyethylene terephthalate chip (intrinsic viscosity 0.60
, Aj with an average particle size of 0.02 μm! After drying at 180°C for 5 hours, 28
It was extruded in a sheet form from a T-die at 5°C and cooled and solidified on a rotating drum kept at 45°C to obtain an unstretched amorphous film with a width of 350D. At that time, a known electrostatic adhesion method was used. The obtained amorphous film was first stretched 1.6 times in the longitudinal direction at a film temperature of 112°C in the first stage by utilizing the peripheral speed difference between the multi-stage nip rolls, and then continuously stretched in the second stage in the longitudinal direction.
As a step, the film was stretched 2.8 times at a film temperature of 143°C.
なお、第1段目の延伸後のフィルムの複屈折率は3.0
X10−’であり、第2段目の延伸後のフィルムの複屈
折率は3.8X10−”であった。かくして得られたフ
ィルムを一端40℃に冷却した後、更にフィルム温度9
s℃まで加熱し、1.22倍で第3段口の縦延伸を行な
った。得られた縦延伸フィルムの複屈折率は0.060
であった。The birefringence index of the film after the first stage stretching is 3.0.
X10-', and the birefringence of the film after the second stage stretching was 3.8X10-'. After cooling the film thus obtained at one end to 40°C, the film temperature was further increased to 9.
It was heated to s° C. and longitudinally stretched at the third stage at a magnification of 1.22 times. The birefringence of the obtained longitudinally stretched film was 0.060.
Met.
次にテンター内で110℃で横方向に3−8倍延伸し、
更に225℃で緊張熱固定を行なって厚さ15μmのフ
ィルムを得た。Next, it was stretched 3-8 times in the transverse direction at 110°C in a tenter.
Further, tension heat setting was performed at 225° C. to obtain a film with a thickness of 15 μm.
比較例工
第3段目の縦延伸倍率を1.01倍とする他は実施例と
同様にして厚さ15μmのフィルムを得た。Comparative Example Process A film with a thickness of 15 μm was obtained in the same manner as in the example except that the longitudinal stretching ratio in the third stage was 1.01 times.
なお、第3段目の縦延伸後の複屈折率は0.042であ
った。Note that the birefringence index after the third stage longitudinal stretching was 0.042.
実施例2.3
第3段目の縦延伸温度を38℃と低くして、かつ延伸倍
率を1.3倍(実施例2)及び1.5倍(実施例3)と
する以外は、実施例1と同様にして製膜し厚さ15μm
のフィルムを得た。Example 2.3 The same procedure was carried out except that the longitudinal stretching temperature in the third stage was as low as 38°C and the stretching ratio was 1.3 times (Example 2) and 1.5 times (Example 3). A film was formed in the same manner as Example 1 to a thickness of 15 μm.
I got a film of.
第3段目の縦延伸後のフィルムの複屈折率はそれぞれ0
.083(実施例2)、0.102(実施例3)であっ
た。The birefringence of the film after the third stage of longitudinal stretching is 0.
.. 083 (Example 2) and 0.102 (Example 3).
比較例2
実施例2において熱固定温度を195℃とする以外は実
施例2と同等にして厚さ15μmのフィルムを得た。Comparative Example 2 A film with a thickness of 15 μm was obtained in the same manner as in Example 2 except that the heat setting temperature was 195° C.
比較例3
実施例1において、第3段目の縦延伸を行なわずに、第
1段目及び第2段目の延伸倍率を各々2゜0倍、3.6
倍とする以外は、実施例1と同様にして厚さ15μmの
フィルムを得た。しかしながら縦延伸での破膜が多く、
長尺のフィルムを採取することは困難であった。Comparative Example 3 In Example 1, the third stage longitudinal stretching was not performed, and the first and second stage stretching ratios were 2°0 times and 3.6 times, respectively.
A film with a thickness of 15 μm was obtained in the same manner as in Example 1 except that the size was doubled. However, there are many cases of membrane rupture during longitudinal stretching;
It was difficult to collect long films.
比較例4
実施例1における未延伸フィルムを縦方向に83℃で3
.0倍延伸した後、−旦冷却して更に79℃で1.3倍
、100℃で3.8倍延伸し、225℃で熱固定して厚
さ15μmのフィルムを得た。Comparative Example 4 The unstretched film in Example 1 was stretched in the longitudinal direction at 83°C for 3
.. After stretching 0 times, it was cooled once, further stretched 1.3 times at 79°C, 3.8 times at 100°C, and heat set at 225°C to obtain a film with a thickness of 15 μm.
以上得られた結果をまとめて表1に示す。The results obtained above are summarized in Table 1.
本発明の磁気テープ用ポリエステルフィルムは、優れた
機械的特性、熱的特性、厚さ斑、走行性、TL磁変換特
性を有しており、その工業的価値は高い。The polyester film for magnetic tape of the present invention has excellent mechanical properties, thermal properties, thickness unevenness, runnability, and TL magnetic conversion properties, and has high industrial value.
出 願 人applicant
Claims (1)
徴とする磁気記録テープ用ポリエステルフィルム。 R^5<5・・・・・・・・・[1] S^1^0^0_3_0≦0.06F_5−0.4・・
・・・・・・・[2] ▲数式、化学式、表等があります▼・・・[3] (但し上記式中、R^5はフィルムの縦方向5mにおけ
る厚さ斑(%)を示し、S_3_0は100℃で30分
間処理後のフィルムの熱収縮率(%)を示し、F_5は
フィルムの縦方向の5%伸張時強度(kg/mm^2)
を示し、n_M_Pはフィルム縦方向の屈折率を示し、
@n@はフィルムの平均屈折率を示す。)(1) A polyester film for magnetic recording tape, characterized in that it satisfies the following formulas [1] to [3] at the same time. R^5<5...[1] S^1^0^0_3_0≦0.06F_5-0.4...
・・・・・・・・・[2] ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・[3] (However, in the above formula, R^5 indicates the thickness unevenness (%) in the vertical direction of the film of 5 m. , S_3_0 indicates the heat shrinkage rate (%) of the film after being treated at 100°C for 30 minutes, and F_5 is the strength at 5% stretching in the longitudinal direction of the film (kg/mm^2)
, n_M_P indicates the refractive index in the longitudinal direction of the film,
@n@ indicates the average refractive index of the film. )
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP32001388A JPH02165413A (en) | 1988-12-19 | 1988-12-19 | Polyester film for magnetic recording tape |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP32001388A JPH02165413A (en) | 1988-12-19 | 1988-12-19 | Polyester film for magnetic recording tape |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH02165413A true JPH02165413A (en) | 1990-06-26 |
Family
ID=18116777
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP32001388A Pending JPH02165413A (en) | 1988-12-19 | 1988-12-19 | Polyester film for magnetic recording tape |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH02165413A (en) |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6147235A (en) * | 1984-08-15 | 1986-03-07 | Diafoil Co Ltd | Manufacturing method of polyester film |
JPS61167532A (en) * | 1985-01-21 | 1986-07-29 | Toray Ind Inc | Biaxially oriented polyester film for magnetic recording medium |
JPS61209155A (en) * | 1985-03-13 | 1986-09-17 | ダイアホイルヘキスト株式会社 | Composite film |
JPS61237623A (en) * | 1985-04-15 | 1986-10-22 | Diafoil Co Ltd | Polyester film for magnetic tape |
-
1988
- 1988-12-19 JP JP32001388A patent/JPH02165413A/en active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6147235A (en) * | 1984-08-15 | 1986-03-07 | Diafoil Co Ltd | Manufacturing method of polyester film |
JPS61167532A (en) * | 1985-01-21 | 1986-07-29 | Toray Ind Inc | Biaxially oriented polyester film for magnetic recording medium |
JPS61209155A (en) * | 1985-03-13 | 1986-09-17 | ダイアホイルヘキスト株式会社 | Composite film |
JPS61237623A (en) * | 1985-04-15 | 1986-10-22 | Diafoil Co Ltd | Polyester film for magnetic tape |
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